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Journal articles on the topic 'Post weld cleaning'
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1
Fuertes, N., V. Bengtsson, R. Pettersson, and M. Rohwerder. "Use of SVET to evaluate corrosion resistance of heat tinted stainless steel welds and effect of post-weld cleaning." Materials and Corrosion 68, no. 1 (June 24, 2016): 7–19. http://dx.doi.org/10.1002/maco.201609048.
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Adam, Wahidun, Pratjojo Dewo, and Winarto Winarto. "Analysis of Weld Cold Cracking In Excavator Bucket Adapter." MATEC Web of Conferences 269 (2019): 03009. http://dx.doi.org/10.1051/matecconf/201926903009.
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This paper presents a failure analysis on welding of bucket adapter for an excavator that made of low carbon steel with Ideal Diameter (DI) value 341 and Carbon Equivalent 0.73. The bucket component is stated OK as the final inspection, but four months later found cracked and even it has not been used yet. Adapter mounted to bucket through CO2 gas shielded Gas Metal Arc Welding (GMAW) process, filler metal MG-50 (AWS A5.18 ER70S-G), pre-heating and post-heating. Crack occurred on the boundary of weld metal and adapter casting. The metallurgical examination was conducted in the crack origin and the adapter casting. Nondestructive test (NDT) covered visual and magnetic test (MT), while destructive test (DT) covered fractography, mechanical properties, and Electron Probe Micro Analyzer (EPMA). The investigation resulted in that crack initiated from slag inclusion in the weld metal due to insufficient cleaning on weld joint. The higher hardness of martensite structure in the heat affected zone (HAZ) of adapter indicates high cooling rate that gen erates high residual stress. High stress that caused by insufficient post heating triggered severe crack propagation. By its characteristic, crack is called the cold cracking, delayed cracking, or hydrogen-induced cracking (HIC).
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Wisnu Wardana, Rahmad, Eakkachai Warinsiriruk, and Sutep Joy-A-Ka. "Selection of Welding Process for Repairing Shredder Hammer by Integrated Data Envelopment Analysis (DEA) and P-robust Technique." MATEC Web of Conferences 269 (2019): 04002. http://dx.doi.org/10.1051/matecconf/201926904002.
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The Selection of the welding process is one of the most significant decision-making problems, and it involves a wide range of information following the type of product. Hence, the automation of knowledge through a knowledge-based system will significantly enhance the decision-making process and simplify for identifying the most appropriate welding processes. The aims of this paper for explicates a knowledge-based system developed for recognising the most suitable welding processes for repairing shredder hammer by using data envelopment analysis (DEA) and p-robust technique. The proposed approach is used for ranking six welding processes which are commonly used, namely shielded metal arc welding (SMAW), flux cored arc welding (FCAW), submerged arc welding (SAW), oxyacetylene gas welding (OAW), gas tungsten arc welding (GTAW), and gas metal arc welding (GMAW). In order to determine the best welding process among competitive welding processes for repairing of shredder hammer, ten parameters are used, namely the availability of consumable, welding process type (manual and automatic), flexibility of welding position, weld-ability on base metal, initial preparation required, welding procedures, post-weld cleaning, capital cost, operating factor, and deposition rate. Furthermore, the sensitivity analysis of regret value (p) is investigated in three cases proposed.
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Brytan, Z., and J. Niagaj. "Corrosion Resistance and Mechanical Properties of TIG and A-TIG Welded Joints of Lean Duplex Stainless Steel S82441 / 1.4662." Archives of Metallurgy and Materials 61, no. 2 (June 1, 2016): 771–84. http://dx.doi.org/10.1515/amm-2016-0131.
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Abstract This paper presents results of pitting corrosion resistance of TIG (autogenous and with filler metal) and A-TIG welded lean duplex stainless steel S82441/1.4662 evaluated according to ASTM G48 method, where autogenous TIG welding process was applied using different amounts of heat input and shielding gases like pure Ar and Ar+N2 and Ar+He mixtures. The results of pitting corrosion resistance of the welded joints of lean duplex stainless steel S82441 were studied in as weld conditions and after different mechanical surface finish treatments. The results of the critical pitting temperature (CPT) determined according to ASTM G48 at temperatures of 15, 25 and 35°C were presented. Three different surface treatment after welding were applied: etching, milling, brushing + etching. The influence of post weld surface treatment was studied in respect to the pitting corrosion resistance, basing on CPT temperature. Research on TIG welding of lean duplex stainless steel S82441/1.4662 showed a clear influence of the applied shielding gas mixtures, where the addition of 5 to 15% N2 to Ar virtually no effect on the level of resistance to pitting corrosion, only 5% N2 addition has a positive effect, while use of a mixture of 50% Ar + 50% He compared with welding at 100% Ar atmosphere, can significantly reduce the resistance to pitting corrosion. Definite good results were obtained during TIG welding with the participation of activation flux (A-TIG). The weld surface of lean duplex stainless S82441/1.4662 obtained in A-TIG welding without the addition of filler metal has a much lower tendency to pitting corrosion than traditional welds made by TIG method. Pitting corrosion resistance of welds made by A-TIG improved with the increase of the heat input in the tested range of welding current 100-200 A. It was also found that the intensity of the occurrence of pitting does not affect the method of cleaning welds after welding, but the mechanical removal of a thin surface layer of metal significantly reduces their intensity.
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Sahir, Samrina, Hwi Won Cho, Nagendra Prasad Yerriboina, Tae Gon Kim, Satomi Hamada, and Jin Goo Park. "Mechanism of PVA Brush Loading with Ceria Particles during Post-CMP Cleaning Process." Solid State Phenomena 314 (February 2021): 259–63. http://dx.doi.org/10.4028/www.scientific.net/ssp.314.259.
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Brush scrubbing is a well-known post CMP cleaning process. Interaction between PVA brush and the particles removed during the process must be considered while designing a cleaning process. In this work, the effect of cleaning solution pH was investigated in terms of particle removal from the wafer and subsequent loading to the PVA brush nodule. Higher cleaning of particles from wafer was observed for pH 2 and 12 cleaning solutions and poor cleaning for pH 7 cleaning solution. In contrast, the brushes were loaded heavily for pH 7 compared to pH 2 and 12. Higher electrostatic attraction between oppositely charged PVA and ceria surfaces provided higher ceria particles loading to PVA brush in acidic and neutral cleaning solutions. This particle loading to PVA brush can further effect cleaning efficiency as well as cross-contamination.
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Philipossian, Ara, Yasa Sampurno, Sian Theng, Fransisca Sudargho, Katherine M. Wortman-Otto, Carolyn Graverson, and Jason J. Keleher. "Tribological Characterization of Anionic Supramolecular Assemblies in Post-STI-CMP Cleaning Solution Using a Novel Post-CMP PVA Brush Scrubber." Solid State Phenomena 314 (February 2021): 264–69. http://dx.doi.org/10.4028/www.scientific.net/ssp.314.264.
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We have shown how different micellar (SDBS) vs. polyelectrolytic (PSSA) supramolecular assemblies in post-CMP cleaning solutions differ in their tribological performance when used in a novel PVA scrubber for 300-mm silicon dioxide wafer cleaning. Significant differences in real-time shear force and coefficient of friction data from the wafer-solution-brush interface (both in time domain as well as frequency domain) have been attributed to differences in each supramolecule’s chemical functionality and structure, which in turn, have been correlated to wafer-level defects. The work has underscored the importance of measuring the tribological attributes of post-CMP cleaning processes in an effort to improve cleaning performance.
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Zhu, Ya Dong, Xiao Ping Yang, and Bao Hong Gao. "A Post-Si CMP Cleaning Using BDD Film Electrochemical Oxidation." Advanced Materials Research 634-638 (January 2013): 169–72. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.169.
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This paper presents a post-Si CMP cleaning using the boron-doped diamond (BDD) film electrode as anode in the electrochemical cleaning method. The BDD film electrode has wide potential window and high oxygen evolution potential, so it is able to electrochemically generate super-advanced oxidation free radicals, such as hydroxyl radicals, oxygen free radicals and so on. And the sub-product of the radicals are ozone and hydrogen peroxide. And the BDD film electrode electrochemically oxidation is an advanced oxidation technology. First using the surfactant to remove particles contaminants, then following this post-Si CMP cleaning, it can effectively remove organic as well as the adsorbed surfactant on the surface. The experiments of cleaning post-Si CMP wafer are introduced in this paper, and the results indicated that the effective cleaning process can meet the continuous development of microelectronic industry cleaning needs.
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Lieten, Ruben R., Daniela White, Thomas Parson, Shi Ning Jenq, Don Frye, Michael White, Lieve Teugels, and Herbert Struyf. "Post-CMP Cleaners for Tungsten at Advanced Nodes." Solid State Phenomena 255 (September 2016): 186–94. http://dx.doi.org/10.4028/www.scientific.net/ssp.255.186.
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We discuss several mechanistic approaches and experimental data for improving post-CMP cleaning of W plugs with TiN as barrier liner, and dielectric substrates SiO2 and Si3N4 for use at the 10 nm technology node (metal pitch of 40 nm). Particle charge in the low pH, W CMP slurries are usually positive, and the W surface is always negatively charged at pH >3. Therefore, a strong electrostatic attraction is expected to occur between the W surface and the residual particles during post-CMP cleaning. Two main approaches were chosen to break down the strong particles-W surface post-CMP electrostatic interactions, as well as particles dispersion and prevention of redeposition: (1) using cleaning additives able to adsorb at the W surface and reverse the W surface charge; (2) using organic additives to reverse the particle charge. The latter approach results in two strongly negative charged surfaces, which are able to repulse each other, and leads to the best cleaning.
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Cazes, M., Christian Pizzetti, Jerome Daviot, Philippe Garnier, Lucile Broussous, Laurence Gabette, and Pascal Besson. "Customized Chemical Compositions Adaptable for Cleaning Virtually all Post-Etch Residues." Solid State Phenomena 282 (August 2018): 121–25. http://dx.doi.org/10.4028/www.scientific.net/ssp.282.121.
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A post-etch residue cleaning formulation, based on balancing the aggressiveness of hydrofluoric acid with its well-known residue removal properties is introduced. In a series of investigations originally motivated by the cleaning challenge provided by high-k dielectric-based residues, a formulation platform is developed that successfully cleans residues resulting from the plasma patterning of tantalum oxide and similar materials while maintaining metal and dielectric compatibility. It is further shown that the fundamental advantages of this solution can be extended to the cleaning of other, more traditional post-etch residues, with no sacrifice in compatibility, as demonstrated by measurements on blanket films and through SEM data.
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Sampurno, Yasa, Yun Zhuang, Xun Gu, Sian Theng, Takenao Nemoto, Ting Sun, Fransisca Sudargho, Akinobu Teramoto, Ara Philipossian, and Tadahiro Ohmi. "Effect of Various Cleaning Solutions and Brush Scrubber Kinematics on the Frictional Attributes of Post Copper CMP Cleaning Process." Solid State Phenomena 145-146 (January 2009): 363–66. http://dx.doi.org/10.4028/www.scientific.net/ssp.145-146.363.
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Brush scrubbing has been widely used in post chemical mechanical planarization (CMP) applications to remove contaminations, such as slurry residues and particles, from the wafer surface. During brush scrubbing, particle removal results from direct contact between a soft poly vinyl alcohol (PVA) brush and the wafer surface in which the brush asperities engulf the particles while the rotating motion of the brush, as well as the cleaning fluid at the surface, dislodge and carry the particles away from the wafer. The cleaning performance of brush scrubbing depends heavily on the choice of the cleaning solution and brush scrubber kinematics. In this work, the effect of various cleaning solutions and brush scrubber kinematics on the frictional attributes of post copper CMP cleaning process was investigated.
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Volhonov, M., Igor' Zimin, and Yuriy Ostrovskiy. "ANALYSIS OF THE STATUS OF PRELIMINARY GRAIN CLEANING IN FARMS OF THE NORTH-WESTERN REGION OF THE RUSSIAN FEDERATION AND PROSPECTS FOR IMPROVEMENT." Vestnik of Kazan State Agrarian University 15, no. 2 (September 8, 2020): 82–86. http://dx.doi.org/10.12737/2073-0462-2020-82-86.
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One of the first operations in the technology of post-harvest processing of a combine heap is preliminary cleaning, which makes it possible to increase the flowability of the material and reduce the cost of drying. In the farms of the North-Western region of the Russian Federation, the grain heap coming from the fields to the processing lines of grain-cleaning and drying complexes is characterized by increased grain mass contamination (15 ... 20%) and a multicomponent composition of trash, which, along with an increase in the moisture content of the grain heap, has a negative effect on the efficiency of the pre-cleaning machines. At grain cleaning and drying points, machines of various designs are used for preliminary grain cleaning. In most cases, they are not intended for separating small weed fractions and separating feed grain, when cleaning a heap with a moisture content of 26 ... 30% or more, their productivity decreases 1.5 ... 2 times. As a result, the wellness of the grain mass is sharply reduced, which in turn reduces the efficiency of storage bins, dryers, as well as machines for primary and secondary grain cleaning. Fundamentally new approaches to the development of designs for grain pre-cleaning machines are required. They must have a high productivity for the coordinated and efficient operation of the entire technological line, as well as carry out preliminary cleaning of grain with its simultaneous separation into feed and seed fractions. Heap cleaners are needed that are capable of separating clean forage from the grain heap already at the first operation, so that it does not need to be additionally cleaned of large weeds and sand, but only needs to be dried on a separate technological line. The pre-cleaner must have a developed air-sieve system and have perfect under-sowing sieves to separate small weed seeds
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Hupka, Lukasz, Jakub Nalaskowski, Nishant Sinha, Joseph N. Greeley, Zak Clark, Hao Du, William P. Johnson, and Jan D. Miller. "Particle – Wafer Interactions in Semiaqueous Silicon Cleaning Systems." Solid State Phenomena 145-146 (January 2009): 77–84. http://dx.doi.org/10.4028/www.scientific.net/ssp.145-146.77.
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Interfacial interaction forces between particulate contaminants and semiconductor wafer surfaces play a key role in the understanding of post-CMP and post-lapping cleaning processes. In order to facilitate removal and prevent re-deposition of submicron particles on wafer surface, understanding, measurement, and manipulation of these forces is required. The theory of interaction forces in liquids that includes DLVO forces (van der Waals, electrical double layer) and non-DLVO (solvation, hydration, hydrophobic, steric and bridging forces) is well established and is studied elsewhere.1-4 Short range interaction forces between silica surfaces in alcohols have been successfully measured before using AFM.5-7
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Qinglong, Lei, Wang Xueqiang, Tang Geng, Dong Liangliang, Liao Yun, Feng Xingzheng, and Yang Yongtao. "Simulation and Experimental Study on Fishing Performance of Vacuum Suction Wellbore Cleaning Tool." Mathematical Problems in Engineering 2020 (July 14, 2020): 1–13. http://dx.doi.org/10.1155/2020/2371059.
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During the completion of shale gas wells, bridge plug debris and debris particles are often left at the bottom of the well, which are difficult to clean up, pose a serious risk to wellbore operations, and reduce productivity. In order to solve the difficulty of cleaning the debris at the bottom of the well, a kind of wellbore cleaning tool is proposed based on the principle of negative jet pressure and liquid-solid two-phase flow theory. The finite element analysis method and laboratory test were used to verify the function of cleaning tools: the finite element method can effectively reflect the principle and process of dredging bottom debris with cleaning tools. In order to improve the applicability and fishing ability of wellbore cleaning tools, factors influencing the performance of cleaning tools were analyzed as follows: choosing high-density and low-viscosity working fluid is beneficial to improve the negative pressure effect of cleaning tools. Under the conditions of wellbore safety and economy, increasing pump pressure and displacement and reducing annular pressure can effectively increase the fishing performance of cleaning tools.
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Кузнецов, Николай, Nikolay Kuznecov, Николай Пушкаренко, Nikolay Pushkarenko, Владимир Медведев, Vladimir Medvedev, Петр Зайцев, et al. "MODEL OF THE TECHNOLOGICAL PROCESS FUNCTIONING OF POST-TREATMENT PROCESSING OF GRAIN IN THE RECEPTION AND PRELIMINARY CLEANING DEPARTMENT OF GRAIN PORES." Vestnik of Kazan State Agrarian University 13, no. 4 (December 19, 2018): 114–18. http://dx.doi.org/10.12737/article_5c3de39977c439.48919234.
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At present, in many regions of the Russian Federation, post-harvest processing of grain is carried out directly on the farms themselves. Produced grain is mainly used for fodder and seed purposes. This is predetermined by difficult weather conditions, and freshly harvested grain is fed to the post-harvest treatment unevenly, it has high humidity and debris, a significant heterogeneity of seeds by ripeness. Machines and equipment of grain cleaning and drying stations and complexes do not fully comply with the properties of the grain pile, which leads to a decrease in their throughput, disruption of processing, the accumulation of large masses of raw grain heap, lengthening the time of harvest, increased losses and reduced quality seeds. Reception and temporary storage of a pile of grain in aerated receiving bunkers with forced ventilation of the pile causes an improvement in the technological properties of the seeds, a decrease in humidity and grain contamination. The use of aerated bunkers for receiving and temporary storage of a grain heap, increase the energy consumption for grain cleaning and heating of the heap. The reduction of specific energy consumption for the operation “Reception of a grain heap” is possible by optimizing both the design parameters and the operating modes of aerated bunkers. The research of the authors showed that the preliminary drying of the grain heap can improve the productivity of the heap cleaner, improve the flowability of the grain pile, the working conditions of the gravity flow devices and the quality of the preliminary cleaning of the grain. The inclusion of the heat generator in the technology of post-harvest processing of grain and the use of heated air in the operations of receiving and pre-cleaning the grain leads to a decrease in the moisture content and grain contamination, an increase in the supply of heap of grain, as well as to the intensification of subsequent technological operations. The paper presents a model of the functioning of the technological process of post-harvest grain processing in the receiving and pre-cleaning unit of the grain pile.
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Lümkemann, Nina, Lisa Marie Schönhoff, Ramona Buser, and Bogna Stawarczyk. "Effect of Cleaning Protocol on Bond Strength between Resin Composite Cement and Three Different CAD/CAM Materials." Materials 13, no. 18 (September 18, 2020): 4150. http://dx.doi.org/10.3390/ma13184150.
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The present investigation tested the effect of the cleaning method on the tensile bond strength (TBS) between one resin composite cement (RCC) and three different computer aided design/computer aided manufacturing (CAD/CAM) materials, namely zirconia, lithium disilicate ceramic and resin composite. Ninety specimens were prepared from each CAD/CAM material (N = 270). The specimens were pre-treated respectively, divided into five subgroups and subjected to five different cleaning protocols, namely i. 37% phosphoric acid, ii. ethanol, iii. phosphoric acid + ethanol, iv. cleaning paste, v. distilled water. After cleaning, the specimens were either conditioned using a universal primer or a universal adhesive and bonded using a dual-curing RCC. After thermo-cycling (20,000x at 5 °C/55 °C), TBS and fracture patterns were evaluated. The data was analyzed using 1- and 2-way Analysis of Variance (ANOVA) with post-hoc Scheffé and partial eta-squared (ƞP²), Kruskal–Wallis, Mann–Whitney U and Chi2 tests (p < 0.05). The CAD/CAM material showed an impact on the BS while the cleaning protocol did not affect the results. Zirconia obtained the highest BS, followed by lithium-disilicate-ceramic. Resin composite resulted in the overall lowest BS. For most fracture patterns, the cohesive type occurred. All tested cleaning protocols resulted in same BS values within one CAD/CAM material indicating that the impact of the cleaning method for the restorative material seems to play a subordinate role in obtaining durable bond strength to resin composite cement. Further, it indicates that the recommended bonding protocols are well adjusted to the respective materials and might be able to compensate the impact of not accurately performed cleaning protocols.
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de Araujo, Eduardo Nery Duarte, Thiago Alonso Stephan Lacerda de Sousa, Luciano de Moura Guimarães, and Flavio Plentz. "Effects of post-lithography cleaning on the yield and performance of CVD graphene-based devices." Beilstein Journal of Nanotechnology 10 (February 5, 2019): 349–55. http://dx.doi.org/10.3762/bjnano.10.34.
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The large-scale production of high-quality and clean graphene devices, aiming at technological applications, has been a great challenge over the last decade. This is due to the high affinity of graphene with polymers that are usually applied in standard lithography processes and that, inevitably, modify the electrical proprieties of graphene. By Raman spectroscopy and electrical-transport investigations, we correlate the room-temperature carrier mobility of graphene devices with the size of well-ordered domains in graphene. In addition, we show that the size of these well-ordered domains is highly influenced by post-photolithography cleaning processes. Finally, we show that by using poly(dimethylglutarimide) (PMGI) as a protection layer, the production yield of CVD graphene devices is enhanced. Conversely, their electrical properties are deteriorated as compared with devices fabricated by conventional production methods.
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Yang, Chan Ki, Jin Goo Park, Jung Hun Jo, Geun Sik Lim, Tae Hyung Kim, and In Soo Jo. "Removal of Slurry Residues in Tungsten Plug during Chemical Mechanical Planarization." Solid State Phenomena 124-126 (June 2007): 157–60. http://dx.doi.org/10.4028/www.scientific.net/ssp.124-126.157.
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One of key processes in tungsten (W) CMP is to remove slurry particles inside W plug after CMP. In general, HF cleaning is well known to remove the slurry residue particles in W plugs. HF chemistry lifts off the particles by etching the plug during scrubbing and effectively removes particles. It is sometimes impossible to apply HF chemisty on W plug due to the degradation of electrical characteristics of a device. In this paper, a post W CMP cleaning process is proposed to remove residue particles without applying HF chemistry. After W CMP, recessed plugs are created, therefore they easily trap slurry particles during CMP process. These particles in recessed plug are not easy to remove by brush scrubbing when NH4OH chemistry is used for the cleaning because the brush surface can not reach the recessed area of plugs. Buffing with oxide slurry was followed by W CMP due to its high selectivity to W. The buffing polishes only oxide slightly which creates higher plug profiles than surrounding oxide. Higher profiles make the brush contact much more effectively and result in a similar particle removal efficiency even in NH4OH cleaning to that in HF brush scrubbing.
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Bunn, Stephanie J. "Water as a Vital Substance in Post-Socialist Kyrgyzstan." Worldviews 17, no. 2 (2013): 125–37. http://dx.doi.org/10.1163/15685357-01702004.
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In Kyrgyzstan, water can be a highly charged substance. Coming from snow-melt and glacial sources in the mountains and associated with all that is clean and cleansing, it is both politically significant and deemed to have the power to heal. Compared to other Central Asian states, there is an abundance of water in Kyrgyzstan. However, its use in hydro-electric power creates significant tensions between Kyrgyz and down-stream Uzbeks who lack water, negotiating for it in exchange for gas. But as well as being negotiated for power, water has its own power. At mazars (holy sites) people come to the waterfalls and springs to collect water for healing, carrying wheel-chairs across the rocks, and taking the water away in bottles. In the Soviet era, healing springs were transformed into sanatoria, or hot baths, the minerals contained in the water listed on posters to reinforce the “scientific” reasons for them being beneficial for health. In contemporary Kyrgyzstan, healers can imbue water with power, but it can also have its own force and affect people, cleansing and protecting them. This paper explores the range of manifestations of power in water and the different kinds of reasoning people apply to explain its potency in the region.
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Mircea, Diana-Maria. "Self-Cleaning Concrete for Landscaping Applications." MATEC Web of Conferences 289 (2019): 05004. http://dx.doi.org/10.1051/matecconf/201928905004.
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Negative effects of environmental pollution pose a significant risk to agriculture, water resources and human health. This can however be reduced by selecting appropriate materials in construction and landscape architecture. It is well-known that strong sunlight or ultraviolet light decomposes many organic materials in a slow natural process. Photocatalytic substances accelerate this process and when used in concrete (which is one of the most widely used construction materials), permit the treatment of pollutants close to their source by applying a self-cleaning principle: decomposing organic materials, biological materials and pollutants into molecules like oxygen, water, carbon dioxide, nitrates, and sulphates. Catalytic material activation will start due to energy that is received from sunlight (it also can be activated using artificial lights), and self-cleaning begins when this material is activated. Beside other properties, this innovative self-cleaning concrete also keeps its colour for far longer than other traditional building materials, making it a desirable solution for landscaping applications.
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Hossain, Md Shahadat, and Md Anisur Rahman. "Post-consumer PET Bottle Recycling: Chemical Dose Optimization." Journal of Engineering Advancements 01, no. 03 (September 15, 2020): 70–75. http://dx.doi.org/10.38032/jea.2020.03.001.
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Polyethylene terephthalate (PET) bottles are being used in our daily life and consequently go to the landfills after their use. Additionally, virgin PET resins are produced from nonrenewable resources, such as fossil fuels, whose reserves are depleting continuously. Therefore, to maintain ecological and environmental balances as well as for sustainable development, post-consumer PET (pcrPET) bottles should be recycled. Among many recycling processes, mechanical recycling of pcrPET is attractive due to lower cost involvement. One of the most crucial and important processes of mechanical recycling is hot washing for contaminants removal. Hot washing uses a cleaning solution made of caustic soda (NaOH) and detergent at elevated temperature. In this paper, caustic soda and FORYL LFO (FLO) detergent doses were changed gradually to investigate effective contaminants removal through colorimetric study. Finally, concentration vs. absorbance graphs from colorimetric study suggests that 2% NaOH and 2% FLO detergent is the optimum chemical dose at hot washing for pcrPET recycling.
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Hopkins, Grant A., and Barrie M. Forrest. "Management options for vessel hull fouling: an overview of risks posed by in-water cleaning." ICES Journal of Marine Science 65, no. 5 (March 7, 2008): 811–15. http://dx.doi.org/10.1093/icesjms/fsn026.
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Abstract Hopkins, G. A., and Forrest, B. M. 2008. Management options for vessel hull fouling: an overview of risks posed by in-water cleaning. – ICES Journal of Marine Science, 65: 811–815. Hull fouling has been identified as an important pathway for the spread of non-indigenous marine species. However, the management of associated biosecurity risks has proven challenging. Left unmanaged, a fouled vessel can pose a biosecurity risk through the detachment and dispersal of viable material, and through spawning by adult taxa upon arrival in a recipient port or region. These risks can be managed effectively through the removal of the vessel to land for defouling (e.g. dry-docking). However, alternative methods are needed for small (e.g. recreational) vessels, as well as for large vessels fouled outside their dry-docking schedule. Among the various treatment options, in-water cleaning is relatively common, although some countries have placed restrictions on this method because of perceived biosecurity risks. Here, we present a conceptual framework that identifies risks posed by in-water cleaning compared with alternatives, including no management. Decisions on the appropriate management option will be influenced by many factors, including the species present, the level of fouling, and the time a vessel spends in a recipient region. It is important that any regulatory changes regarding in-water defouling be supported by relevant research that quantifies the risks associated with the various management options.
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Yuniar, Silky Amanda, Edy Nursanto, and Rika Ernawati. "POST-COMBUSTION COAL DESULFURIZATION Review." Eksergi 17, no. 2 (December 11, 2020): 79. http://dx.doi.org/10.31315/e.v17i2.3828.
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The sulfur content in coal ranges from 0.5 to 5%, and it is an impurity that must be removed before burning coal, due to the toxic effects and acid rain caused by SO2 gas generated from sulfur oxidation. Sulfur cleaning technology can be carried out on coal before combustion (pre-combustion), and can reduce the inorganic sulfur content by up to 50%; however, it cannot reduce the organic sulfur content. Therefore, the industry relies on post-combustion desulfurization to remove SO2 from the gas from coal combustion. The aim of the coal desulfurization review is to direct desulfurization research to be efficient and effective, as well as to be environmentally friendly. Sulfur in coal consists of organic sulfur and inorganic sulfur. Coal inorganic sulfur consists of pyrite (FeS2), sulfate, and sulfide. The largest composition is pyrite. Organic sulfur consists of hetero-atomic and heterocyclic (thiophenic) macromolecules that bind N and O atoms, aromatic sulfides, and aromatic disulfides (small amounts). Inorganic sulfur can easily be separated from coal by means of flotation, microwave energy, magnetic forces, ultrasonic energy, and as well as microorganisms. Meanwhile, organic sulfur cannot be separated from coal by using the methods used in the inorganic sulfur separation process. Organic sulfur can be removed by chemical and biodesulfurization, however, this process is inefficient for industrial scale. The most recommended method is the absorption of SO2 gas in the gas from coal combustion, or post-combustion desulfurization. Various methods have also been investigated to separate SO2 gas, and more details will be described in this paper.
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Martin, Elena K., Elizabeth L. Salsgiver, Daniel A. Bernstein, Matthew S. Simon, William G. Greendyke, James M. Gramstad, Roydell Weeks, et al. "Sustained improvement in hospital cleaning associated with a novel education and culture change program for environmental services workers." Infection Control & Hospital Epidemiology 40, no. 9 (July 1, 2019): 1024–29. http://dx.doi.org/10.1017/ice.2019.183.
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AbstractObjective:To sustainably improve cleaning of high-touch surfaces (HTSs) in acute-care hospitals using a multimodal approach to education, reduction of barriers to cleaning, and culture change for environmental services workers.Design:Prospective, quasi-experimental, before-and-after intervention study.Setting:The study was conducted in 2 academic acute-care hospitals, 2 community hospitals, and an academic pediatric and women’s hospital.Participants:Frontline environmental services workers.Intervention:A 5-module educational program, using principles of adult learning theory, was developed and presented to environmental services workers. Audience response system (ARS), videos, demonstrations, role playing, and graphics were used to illustrate concepts of and the rationale for infection prevention strategies. Topics included hand hygiene, isolation precautions, personal protective equipment (PPE), cleaning protocols, and strategies to overcome barriers. Program evaluation included ARS questions, written evaluations, and objective assessments of occupied patient room cleaning. Changes in hospital-onset C. difficile infection (CDI) and methicillin-resistant S. aureus (MRSA) bacteremia were evaluated.Results:On average, 357 environmental service workers participated in each module. Most (93%) rated the presentations as ‘excellent’ or ‘very good’ and agreed that they were useful (95%), reported that they were more comfortable donning/doffing PPE (91%) and performing hand hygiene (96%) and better understood the importance of disinfecting HTSs (96%) after the program. The frequency of cleaning individual HTSs in occupied rooms increased from 26% to 62% (P < .001) following the intervention. Improvement was sustained 1-year post intervention (P < .001). A significant decrease in CDI was associated with the program.Conclusion:A novel program that addressed environmental services workers’ knowledge gaps, challenges, and barriers was well received and appeared to result in learning, behavior change, and sustained improvements in cleaning.
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Rardin, Anthony B., Simon J. Kirk, and Mel P. Zussmann. "Enabling Thin Wafer Metal to Metal Bonding through Integration of High Temperature Polyimide Adhesives and Effective Copper Surface Cleaners." Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2010, DPC (January 1, 2010): 001008–29. http://dx.doi.org/10.4071/2010dpc-tp32.
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This paper will examine the use of high temperature Polyimide temporary adhesives and advanced copper cleaning solutions for thin wafer handling during metal to metal (Cu-Cu) bonding. In the case of Cu to Cu solid state diffusion bonding, temperature requirements can be up to 400C for as long as 40 minutes. These extreme conditions pose a significant challenge with existing materials used for temporary bonding. Polyimides are ideally suited for high temperature application and polyimide adhesives have been developed which can withstand 400°C processing without significant failure in adhesion. As well, Cu to Cu bonding processes will require the need for contamination free surfaces, which becomes increasingly important if lower temperature processes (<400C) are desired. Close-coupled copper cleaning immediately prior to the bonding step offers an excellent approach for providing process reproducibility while achieving increased electrical yields. Utilizing advanced wet cleaning solutions to obtain optimal Cu surface preparation through the removal of undesirable copper oxide layers as well as organic contaminants such as Benzotriazole (BTA) is also discussed in detail.
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Kent, Tyler, Mary Edmonds, Ravi Droopad, and Andrew C. Kummel. "InGaAs (110) Surface Cleaning Using Atomic Hydrogen." Solid State Phenomena 219 (September 2014): 47–51. http://dx.doi.org/10.4028/www.scientific.net/ssp.219.47.
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A major obstacle facing III-V semiconductor based metal oxide semiconductor field effect transistors (MOSFETs) is the large density of trap states that exist at the semiconductor/oxide interface.[1] These trap states can pin the Fermi level preventing the MOSFET from acting as a switch in logic devices. Several sources of Fermi level pinning have been proposed including oxidation of the III-V substrate.[2, 3] In order to minimize the presence of III-V oxides it is crucial to employ either an ex-situ etch or to use an in-situ method such as atomic hydrogen cleaning.[4, 5] Although atomic H cleaning of III-V surfaces is well known, it has never been demonstrated on InGaAs (110) crystallographic faces. Furthermore, tri-gate field effect transistors (finFETs) have recently been employed in commercially available logic chips.[6] This unique device architecture allows for a reduction in short channel effects, minimization of the subthreshold swing, and a higher transconductance.[7] The InGaAs (110) surface would be the sidewalls of a vertically aligned (001) based finFETs.[8] Therefore, it is essential to find an in-situ method to efficiently remove any oxides or contamination from the (110) surfaces that is also compatible with the (001) surface. In this study, STM was employed to determine if atomic hydrogen can be used to remove the native oxide from air exposed InGaAs (110) samples. A post clean anneal was used to restore the surface to molecular beam epitaxy (MBE) levels of cleanliness.
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Wang, Z. Z., T. Zsirai, K. Connery, M. Fabiyi, A. Larrea, J. Li, and S. J. Judd. "Biomass properties and permeability in an immersed hollow fibre membrane bioreactor at high sludge concentrations." Water Science and Technology 69, no. 11 (March 28, 2014): 2324–30. http://dx.doi.org/10.2166/wst.2014.142.
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This study aimed to investigate the influence of biomass properties and high mixed liquor suspended solids (MLSS) concentrations on membrane permeability in a pilot-scale hollow fibre membrane bioreactor treating domestic wastewater. Auxiliary molasses solution was added to maintain system operation at constant food-to-microorganisms ratio (F/M = 0.13). Various physicochemical and biological biomass parameters were measured throughout the trial, comprising pre-thickening, thickening and post-thickening periods with reference to the sludge concentration and with aerobic biotreatment continuing throughout. Correlations between dynamic changes in biomass characteristics and membrane permeability decline as well as permeability recovery were further assessed by statistical analyses. Results showed the MLSS concentration to exert the greatest influence on sustainable membrane permeability, with a weaker correlation with particle size distribution. The strong dependence of absolute recovered permeability on wet accumulated solids (WACS) concentration, or clogging propensity, revealed clogging to deleteriously affect membrane permeability decline and recovery (from mechanical declogging and chemical cleaning), with WACS levels increasing with increasing MLSS. Evidence from the study indicated clogging may permanently reduce membrane permeability post declogging and chemical cleaning, corroborating previously reported findings.
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BURKOV, ALEKSANDR I. "DETERMINATION OF THE BASIC DESIGN AND TECHNOLOGICAL PARAMETERS OF THE PNEUMATIC SEPARATING DEVICE OF A CLOVER THRESHER AND SCARIFIER." Agricultural engineering, no. 4 (2021): 9–13. http://dx.doi.org/10.26897/2687-1149-2021-4-9-13.
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The most labor-intensive stages of the post-harvest processing of grass seeds are their extracting and cleaning from impurities. For extracting seeds from the hull of clover and other leguminous and cereal grasses, as well as scarifi cation of solid seeds of leguminous grasses, the clover thresher and scarifi er KS-0.2 has been developed. It lacks a device for cleaning the extracted seeds from impurities, which makes it diffi cult to further clean them at subsequent stages of the processing line. To eliminate this disadvantage, a pneumatic separating device was fi tted for cleaning seeds from light impurities. The research aimed at experimental substantiation of the basic constructive and technological parameters of the pneumatic separating device of the clover thresher and scarifi er, ensuring cleaning from light impurities of more than 60%. The study was carried out according to conventional techniques using methods of planning a multi-factor experiment on a laboratory installation of a clover thresher when cleaning red clover seeds from light impurities. The study results have shown that the maximum eff ect of cleaning from light impurities reaches 96.7% with a minimum feed of source material of 200 kg/h, the angle of the grain board inclination of 42.85° and a maximum depth of the aspirating channel of 0.11 m. Based on design considerations and the maximum throughput of the clover thresher and scarifi er, the following combination of factors was chosen as the optimal one: a feed of the source material of 300 kg/h, an inclination angle of the grain board of 45° and a depth of the aspirating channel of 0.09 m. With this combination of factors, the eff ect of cleaning from light impurities meets the technical requirements and equals 75.2%. Thus, the study has determined the basic design and technological parameters of the pneumatic separating device of the clover thresher and scarifier.
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Martin, Robert, Sokunroth Chhun, Sophea Yous, Ratha Rien, Chariya Korn, and Pao Srean. "Survey of Weed Management Practices in Direct-Seeded Rice in North-West Cambodia." Agronomy 11, no. 3 (March 6, 2021): 498. http://dx.doi.org/10.3390/agronomy11030498.
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Two-hundred rice farming households from eight lowland rice villages in North-West Cambodia were surveyed in 2020 to determine changes in farmers’ knowledge, weed management practices and weed seed contamination in seed kept for sowing. The major yield constraints cited by farmers were lack of water, inability to manage water and competition by weeds. Water shortages result in reduced crop establishment, non-optimal herbicide application timing and poor weed control. Reduced tillage, drill planting and use of pre-emergence herbicides can improve weed management. The adoption of drill planting improves crop establishment and enables the use of pre-emergence herbicides. Possible reasons for changes in weed problems include the change to a two-crop rice system in the wet season and spread of seeds by harvesting machines. The main weed seed contaminants of rice seed kept for sowing were Echinochloa crus-galli, E. colona, Fimbristylis miliacea, Ischaemum rugosum and Melochia corchorifolia. F. miliacea was the only species effectively removed by village cleaning methods. Although prevalent in rice fields, Cyperus. iria with <0.2 seeds per 500 g and Leptochloa chinensis with nil contamination were insignificant contaminants of seed samples. The majority of farmers in the study area are relying on repeated use of a narrow range of post-emergence herbicides, thus leading to increased severity of weed problems in dry direct-seeded rice. Integrated weed management is required to reduce over-reliance on post-emergence herbicides. This will require engagement with the local input supply network to introduce advice on improved weed management and sustainable herbicide use.
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Sfriso, Riccardo, and Joshua Claypool. "Microbial Reference Frames Reveal Distinct Shifts in the Skin Microbiota after Cleansing." Microorganisms 8, no. 11 (October 23, 2020): 1634. http://dx.doi.org/10.3390/microorganisms8111634.
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Skin cleansing represents a process of mechanical and chemical removal of dirt, pollutants as well as microbiota from the skin. While skin cleansing can help maintain good health, protect us from infections, illnesses and ailments, skin cleansing can also strip away lipids and moisture from the skin, leading to irritation, barrier impairment and disturbance of the delicate cutaneous microbiome. This study investigated how skin cleansing impacts skin’s microbial composition. Thirty Caucasian women were enrolled in a placebo controlled clinical study where participants applied on their volar forearms a liquid body wash twice daily for 1 week in order to mimic frequent showering. Skin microbiome samples were collected by swabbing at defined timepoints and 16S rRNA sequencing was performed. Using “reference frames”, we could identify shifts in the microbial composition and several microbiota were identified as being characteristically associated with the presence of saccharide isomerate, a well-known skin moisturizer. The microbial shift was quite immediate, and we could observe it already at 1 h post cleansing. Interestingly, the new microbial composition reached a certain dynamic equilibrium at day 1 which was then maintained until the end of the study. Paracoccus marcusii, a potentially beneficial carotenoid-producer microorganism, was enriched by the active treatment and, at the same time, the abundance of several potential pathogenic taxa, Brevibacterium casei and Rothia mucilaginosa, diminished.
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Ryu, Heon Yul, Palwasha Jalalzai, Nagendra Prasad Yerriboina, Tae Gon Kim, Satomi Hamada, and Jin Goo Park. "Effect of Dissolved Oxygen on Removal of Benzotriazole from Co during a Post-Co CMP Cleaning." Solid State Phenomena 314 (February 2021): 270–74. http://dx.doi.org/10.4028/www.scientific.net/ssp.314.270.
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A systematic study of the adsorption of benzotriazole on Co surface and its removal in aqueous solutions was carried out for post-CMP cleaning application. Static etch rate (SER) measurements and electrochemical impedance spectroscopy (EIS) were employed. The experimental results show that BTA adsorbed well on Co surface when it exposed to BTA solution at neutral and alkaline pH. BTA did not adsorb due to active Co dissolution at acidic pH. The effect of dissolved oxygen (DO) concentration in de-ionized (DI) water on the removal of Co-BTA complex layer was investigated. At DI water rinse process after BTA treatment, Co-BTA layer was maintained on Co surface when DO concentration of DI water was low. Interestingly, BTA was removed by DI water with high DO concentration.
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Li, Xinping, Gaoyuan Zhao, Wenzhe Wang, Yu Huang, and Jiangtao Ji. "Design and Experiment of Vibrating Screen Millet Cleaning Devise with Double-fan." Applied Engineering in Agriculture 37, no. 2 (2021): 319–31. http://dx.doi.org/10.13031/aea.14173.
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HighlightsAccording to the physical characteristics of the millet, the double-layer mesh vibrating screen was used as the cleaning screen to prolong the cleaning time of the millet in the cleaning room, prevent the blocking of the vibrating screen, and improve the cleaning performance of the millet cleaning device.As the air flow produced by centrifugal fan was continuously attenuated on the screen surface, the draft chaser cannot completely discharge the chaffs, stalks and other sundries outside the machine. The cross-flow fan designed at the tail of the vibrating screen worked well for increasing the air flow field, improving the cleaning performance.In order to reduce the unthreshed grain-codes in the threshed mixture, a re-threshing device was installed for the millet cleaning device that transported sundries at the end of the screen to the main threshing roller for re-threshing, which improved the cleaning rate and reduced the loss rate effectively.The mathematical model of four factors quadric regression between the rotating speed of centrifugal fan, cross-flow fan, frequency of vibrating screen, width of sundry outlet and the cleaning performance of the device was established, which was meaningful and had high fitting degree. The results of indoor test shown that the cleaning rate was 98.8% and the loss rate was 1.3%.The results of bench test and field test shown that when the size of the upper screen was 12×12 mm, the size of the lower screen was 6×6 mm, the diameter of the suction port of the cross-flow fan was 15 mm, the rotating speed of the centrifugal fan was 1406 r/min, the rotating speed of the cross-flow fan was 713 r/min, the frequency of the vibrating screen was 5.9 Hz, and the width of the sundry outlet was 178 mm, the cleaning rate of the millet cleaning device was 98.75%, and the loss rate was 1.34%.Abstract. The cleaning device is an important part of the millet combine harvester, which directly affects the performance of the whole machine. Aiming at the problems of low cleaning rate and high loss rate in the traditional air-and-screen cleaning device, a vibrating screen millet cleaning device with double-fan was designed. The structure and relevant parameters of the vibrating screen millet cleaning device with double-fan were analyzed and determined. The effects of the rotating speed of centrifugal fan, the rotating speed of cross-flow fan, the vibrating frequency of vibrating screen and the width of the sundry outlet on the millet cleaning rate and the loss rate were studied by single factor test and the orthogonal combination test of four element quadratic rotation. The regression equation between the rotating speed of centrifugal fan, the rotating speed of cross-flow fan, the vibrating frequency of vibrating screen and the width of the sundry outlet and the millet cleaning rate and the loss rate are constructed was used to optimize and obtain the operation parameters of the cleaning device. The indoor test results showed that when the centrifugal fan speed was 1406 r/min, the cross-flow fan speed was 726 r/min, the vibrating screen frequency was 5.9 Hz, and the width of the sundry outlet was 178 mm, the millet cleaning rate was 98.8%, and the loss rate was 1.3%. The result of field test showed that the cleaning rate and loss rate of the vibrating screen millet cleaning device with double-fan were 98.75% and 1.34%, respectively. Keywords: Double-fan, Double-layer mesh vibrating screen, Field test, Millet.
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Ali, Rashid, Marc-André Bünzli, Luca Colombo, Seema Anjum Khattak, Sebastián Pera, Mohammad Riaz, and Claudio Valsangiacomo. "Water quality before and after a campaign of cleaning and disinfecting shallow wells: a study conducted during and after floods in Khyber Pakhtunkhwa, Pakistan." Journal of Water, Sanitation and Hygiene for Development 9, no. 1 (November 7, 2018): 28–37. http://dx.doi.org/10.2166/washdev.2018.272.
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Abstract This study reports on a water quality assessment of the Water, Sanitation and Hygiene program implemented by the Swiss Agency for Development and Cooperation in the districts of Charsadda and Nowshera in Khyber Pakhtunkhwa, Pakistan, in the aftermath of the severe flood of 2010. During emergency operations, over 4,500 shallow wells were cleaned using the standard protocol suggested by the World Health Organization. Bacteriological analysis and chemical-physical parameters such as temperature, conductivity, turbidity and pH were tested before and after cleaning. Four to five years after the emergency operation, in 2014–15, a set of 105 representative wells was analyzed again, considering the same parameters and looking for additional contaminants (pesticides, arsenic and fluoride). The post-flood well-cleaning campaign was effective in the immediate reduction of fecal contamination of water (from 85% to 20% as measured 7–30 days after cleaning); however in the following months/years the rate of fecal contamination rose again (up to 62% of all measured domestic wells, n = 105). Along with laboratory analysis data, this study investigated the source of contamination of shallow wells and identified human practices in several cases. This information was useful for the design of future SDC interventions in the WASH sector.
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STORR, VIRGIL HENRY, LAURA E. GRUBE, and STEFANIE HAEFFELE-BALCH. "Polycentric orders and post-disaster recovery: a case study of one Orthodox Jewish community following Hurricane Sandy." Journal of Institutional Economics 13, no. 4 (February 28, 2017): 875–97. http://dx.doi.org/10.1017/s1744137417000054.
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AbstractHurricane Sandy hit the East Coast of the United States on 29 October 2012, flooding hundreds of thousands of homes and costing over $50 billion in property damage. After Hurricane Sandy residents and communities required food, water and clothing, and in the weeks and months following, there was demand for cleaning supplies, building materials and contracting services. Polycentric orders, because of their flexibility and access to local knowledge, are well suited to respond to the challenges of disaster. We highlight the importance of privately provided social services within polycentric orders and illustrate that the private provision of these services was important to post-disaster recovery in the Orthodox Jewish community in the Rockaway Peninsula in New York.
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Franz, Roland, and Frank Welle. "Contamination Levels in Recollected PET Bottles from Non-Food Applications and their Impact on the Safety of Recycled PET for Food Contact." Molecules 25, no. 21 (October 28, 2020): 4998. http://dx.doi.org/10.3390/molecules25214998.
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PET beverage bottles have been recycled and safely reprocessed into new food contact packaging applications for over two decades. During recollection of post-consumer PET beverage bottles, PET containers from non-food products are inevitably co-collected and thereby enter the PET recycling feed stream. To explore the impact of this mixing on the safety-in-use of recycled PET (rPET) bottles, we determined the concentrations of post-consumer substances in PET containers used for a range of non-food product applications taken from the market. Based on the chemical nature and amounts of these post-consumer substances, we evaluated their potential carry-over into beverages filled in rPET bottles starting from different fractions of non-food PET in the recollection systems and taking worst-case cleaning efficiencies of super-clean recycling processes into account. On the basis of the Threshold of Toxicological Concern (TTC) concept and Cramer classification tools, we present a risk assessment for potential exposure of the consumer to the identified contaminants as well as unidentified, potentially genotoxic substances in beverages. As a result, a fraction of 5% non-food PET in the recycling feed stream, which is very likely to occur in the usual recollection systems, does not pose any risk to the consumer. Our data show that fractions of up to 20%, which may sporadically be contained in certain, local recollection systems, would also not raise a safety concern.
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Paula, José Ricardo, Eve Otjacques, Courtney Hildebrandt, Alexandra S. Grutter, and Rui Rosa. "Ocean Acidification Does Not Affect Fish Ectoparasite Survival." Oceans 1, no. 1 (February 18, 2020): 27–33. http://dx.doi.org/10.3390/oceans1010003.
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The juveniles of gnathiid isopods are one of the most common fish ectoparasites in marine habitats and cause deleterious effects on fish by feeding on host blood and lymph. Reef fishes tend to engage in cooperative interactions with cleaning organisms to reduce their ectoparasite load. Ocean acidification (OA) pose multiple threats to marine life. Recently, OA was found to disrupt cleaner fish behaviour in mutualistic cleaning interactions. However, the potential effects of ocean acidification on this common ectoparasite remains unknown. Here, we test if exposure to an acidification scenario predicted by IPCC to the end of the century (RCP 8.5 – 980 μatm pCO2) affects gnathiid survival. Our results show that ocean acidification did not have any effects on gnathiid survival rate during all three juvenile life stages. Thus, we advocate that the need for cleaning interactions will persist in potentially acidified coral reefs. Nevertheless, to better understand gnathiid resilience to ocean acidification, future studies are needed to evaluate ocean acidification impacts on gnathiid reproduction and physiology as well as host-parasite interactions.
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Jährig, Jeannette, Leo Vredenbregt, Daniel Wicke, Ulf Miehe, and Alexander Sperlich. "Capillary Nanofiltration under Anoxic Conditions as Post-Treatment after Bank Filtration." Water 10, no. 11 (November 7, 2018): 1599. http://dx.doi.org/10.3390/w10111599.
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Bank filtration schemes for the production of drinking water are increasingly affected by constituents such as sulphate and organic micropollutants (OMP) in the source water. Within the European project AquaNES, the combination of bank filtration followed by capillary nanofiltration (capNF) is being demonstrated as a potential solution for these challenges at pilot scale. As the bank filtration process reliably reduces total organic carbon and dissolved organic carbon (DOC), biopolymers, algae and particles, membrane fouling is reduced resulting in long term operational stability of capNF systems. Iron and manganese fouling could be reduced with the possibility of anoxic operation of capNF. With the newly developed membrane module HF-TNF a good retention of sulphate (67–71%), selected micropollutants (e.g., EDTA: 84–92%) and hardness (41–55%) was achieved together with further removal of DOC (82–87%). Fouling and scaling could be handled with a good cleaning concept with acid and caustic. With the combination of bank filtration and capNF a possibility for treatment of anoxic well water without further pre-treatment was demonstrated and retention of selected current water pollutants was shown.
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Sourd, Xavier, Mehdi Salem, Redouane Zitoune, Akshay Hejjaji, and Damien Lamouche. "Titanium Alloy Milling Using Abrasive Water Jet for Repair Application: Modifications in Surface Quality and Material Integrity Following Plain Water Jet Cleaning." Materials Science Forum 1016 (January 2021): 1374–80. http://dx.doi.org/10.4028/www.scientific.net/msf.1016.1374.
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Abrasive Water Jet (AWJ) machining has proven to be an effective and versatile technique for milling various kinds of materials, even with low machinability such as aerospace grade titanium alloy Ti6Al4V. Many studies have been performed in order to master this technology and produce geometrically accurate shapes. However, in the context of bonding repairs which require surfaces free from foreign bodies, AWJ machining presents a significant drawback in form of abrasive grit embedment. The goal of this present work is then to investigate the effect of a post-AWJ machining cleaning operation using Plain Water Jet process (PWJ – i.e. without abrasive particles) on the surface quality and material properties. For this, several characterization techniques were employed. It was concluded that the contamination has been reduced by 65% without noticeable changes in depth of cut and crater volume. The AWJ milling operation produced surface and subsurface hardening as well as biaxial compressive residual stress, mostly piloted by the jet pressure. PWJ cleaning reduced the depth of hardening without clear modification in surface hardness.
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Araźna, Aneta, Konrad Futera, Małgorzata Jakubowska, and Łucja Dybowska-Sarapuk. "Investigation of treated PEN foil surface properties for inkjet application." Soldering & Surface Mount Technology 27, no. 3 (June 1, 2015): 108–11. http://dx.doi.org/10.1108/ssmt-03-2015-0007.
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Purpose – The purpose of this paper is to report surface properties of treated Teonex Du Pont polyethylene naphthalate (PEN) foil substrates. Design/methodology/approach – There were three different cleaning treatments among other: argon glow discharge, dipping into alkaline solution at 60°C as well as washing in an ultrasonic bath of acetone and ethyl alcohol in room temperature. The relation between PEN foil morphology and surface properties has been studied by contact angle measurements as well as evaluation of surface roughness of PEN foil samples by atomic force microscopy (AFM). Findings – It was found that argon glow discharge (T3) of PEN treatment caused the maximum reduction in both values of contact angles. In addition, the argon glow discharge yielded the highest PEN surface energy (51.9 mJ/m2) and polarity (0.89). On the other hand, the AFM micrographs showed that the samples T3 had the highest value of average and root mean square surface roughness. Based on the experiments results, the authors stated that the alkaline cleaning (T2 treatment) could be considered as an effective method of PEN substrate treatment. Originality/value – The influence of different cleaning treatment on the surface properties of PEN foil to inkjet application was analyzed. In the literature, there are not a lot of papers describing examinations of surface properties of PEN foil to inkjet application by contact angle measurements and AFM analysis.
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Dolcemore, Liz. "Legacies of Violence: Examining the Relationship Between Gender and Ethnic Cleansing." Political Science Undergraduate Review 2, no. 1 (October 15, 2016): 5–14. http://dx.doi.org/10.29173/psur58.
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Traditional examinations of genocidal violence tend to focus on ethnic divisions and often fail to consider the impact of gender with respect to conflict. Building from the work that critical gender studies has made in post-conflict peacebuilding, this paper will look at cases that illustrate how targeting women within specific ethnic groups is an effective means of achieving genocidal goals. It will pay particular attention to the well-known events of the Rwandan genocide and draw comparisons to the legacies of the Indigenous genocide in Canada. Moreover, it will argue that the current crisis of murdered and missing Indigenous women in Canada is related to a project of genocide fuelled by settler colonialism.
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Kaestle, Christopher, Aarief Syed-Khaja, and Joerg Franke. "Investigations on the Wire Bonding Capability on Selective Laser Melted Structures." International Symposium on Microelectronics 2016, no. 1 (October 1, 2016): 000209–13. http://dx.doi.org/10.4071/isom-2016-wa43.
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Abstract The paper displays the influencing factors, as well as the possibilities and challenges that come along with the process combination of selective laser melting (SLM) and heavy wire bonding. For the investigations, test samples were created from bronze powder on a SLM-machine. Then, 300 μm aluminum and copper wires were bonded on the SLM generated structures. Wire bonding capability is analyzed on untreated as well as on post-processed surfaces. The influence and effectiveness of various steps of post-processing such as cleaning, sandblasting and grinding are analyzed. Thus, interdependencies between both manufacturing process as well as the post-processing can be revealed. The effect of surface roughness and hardness of the assembly partner are investigated as well. To draw statistically backed conclusions, all tests are performed using DoE (Design of Experiment) studies. The primary characteristics besides the bond parameters that influence the wire bonding capability are focused in this paper. The process stability as well as the interconnection quality are evaluated by optical non-destructive laser microscopic analysis. Destructive pull and shear tests and metallographic cross sections are performed to evaluate the adhesion characteristics. The process stability and the yield obtained are important factors to describe the process and to evaluate the industrialization potential. By a profound understanding of all interdependencies between the two processes, a flexible manufacturing technology for power devices can be established.
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Kulkarni, Prachi, Megan Shoff, and Anne Lucas. "Comparison of Test Methods To Screen For Residual Chemical Contamination On Medical Device Surfaces." Biomedical Instrumentation & Technology 46, no. 5 (September 1, 2012): 388–94. http://dx.doi.org/10.2345/0899-8205-46.5.388.
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Abstract Reprocessing medical devices involves several steps including cleaning and disinfection or sterilization. Chemical residuals can occur at various stages of reprocessing. These residues could interfere with device function and potentially harm patients. These solutions are composed of a combination of various chemicals and their residues are highly diluted post rinsing, therefore, it is difficult to find a sensitive and rapid method to detect toxicity due to chemical residues. This study focused on (1) finding the levels of residues that are cytotoxic using two mammalian cell lines and Daphnia magna, and (2) evaluating two test methods, Total Organic Carbon (TOC) and the Luminescent Bacteria Test (LBT), to measure residual chemicals levels. The two mammalian cell lines were equal in their cytotoxicity responses. However, Daphnia were more sensitive to some chemical residue than the two mammalian cell lines. TOC and LBT were able to detect the presence of residue well below the levels that were determined to cause mammalian cytotoxicity. LBT was more sensitive for some chemicals and TOC for others, both in solution and in simulated cleaning and rinsing for the limited number of solutions tested in this study.
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Hohmann, Maria-Franziska, Nicole Wente, Yanchao Zhang, and Volker Krömker. "Bacterial Load of the Teat Apex Skin and Associated Factors at Herd Level." Animals 10, no. 9 (September 14, 2020): 1647. http://dx.doi.org/10.3390/ani10091647.
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In order to reduce antimicrobial treatment and prevent environmental mastitis, the aim of the present study was to investigate associations between herd level factors and microbial load on teat ends with environmental mastitis pathogens. Quarterly farm visits of 31 dairy farms over a one-year period were used for statistical analysis. During each farm visit, teat-skin swabs, bedding and air samples were taken and management practices and herd parameters were documented. Total mesophilic bacteria, esculin-positive streptococci and coliform bacteria were examined in the laboratory procedures from teat skin and environmental samples. Esculin-positive streptococci and coliform bacteria on teat ends increased with high temperature–humidity indices (THI) in the barn during the spring and summer. Significantly more coliform bacteria on teat ends were found in herds with an increased percentage of normal or slightly rough teat ends. Cleaning cubicles more frequently, pre-cleaning teats before milking as well as post-dipping them after milking had a decreasing effect of teat-skin load with total mesophilic and coliform bacteria at the herd level. To conclude, teat-skin bacterial load with environmental pathogens is subject to fluctuations and can be influenced by aspects of farm hygiene.
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Cunnington, Steven, Melis O. Irfan, Isabella P. Carucci, Alkistis Pourtsidou, and Jérôme Bobin. "21-cm foregrounds and polarization leakage: cleaning and mitigation strategies." Monthly Notices of the Royal Astronomical Society 504, no. 1 (March 26, 2021): 208–27. http://dx.doi.org/10.1093/mnras/stab856.
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ABSTRACT The success of H i intensity mapping is largely dependent on how well 21-cm foreground contamination can be controlled. In order to progress our understanding further, we present a range of simulated foreground data from two different ∼3000 deg2 sky regions, with varying effects from polarization leakage. Combining these with cosmological H i simulations creates a range of intensity mapping test cases that require different foreground treatments. This allows us to conduct the most generalized study to date into 21-cm foregrounds and their cleaning techniques for the post-reionization era. We first provide a pedagogical review of the most commonly used blind foreground removal techniques [principal component analysis (PCA)/singular value decomposition (SVD), fast independent component analysis (FASTICA), and generalized morphological component analysis (GMCA)]. We also trial a non-blind parametric fitting technique and discuss potential hybridization of methods. We highlight the similarities and differences in these techniques finding that the blind methods produce near equivalent results, and we explain the fundamental reasons for this. Our results demonstrate that polarized foreground residuals should be generally subdominant to H i on small scales ($k\gtrsim 0.1\, h\, \text{Mpc}^{-1}$). However, on larger scales, results are more case dependent. In some cases, aggressive cleans severely damp H i power but still leave dominant foreground residuals. We find a changing polarization fraction has little impact on results within a realistic range (0.5–2 per cent); however, a higher level of Faraday rotation does require more aggressive cleaning. We also demonstrate the gain from cross-correlations with optical galaxy surveys, where extreme levels of residual foregrounds can be circumvented. However, these residuals still contribute to errors and we discuss the optimal balance between overcleaning and undercleaning.
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Yates, Timothy. "Studies of Non-Marine Mollusks for the Selection of Shell Samples for Radiocarbon Dating." Radiocarbon 28, no. 2A (1986): 457–63. http://dx.doi.org/10.1017/s0033822200007591.
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14C dating of shells from terrestrial and freshwater mollusks is prone to distortion by post-depositional diagenesis as well as incorporation of material depleted in 14C while the mollusk was alive. Three types of diagenetic change can result: etching, the development of surface crusts, and replacement of aragonite by calcite. Inspection under the light microscope, x-ray diffraction, and scanning electron microscope make it possible to assess the relative importance of the changes. When they are confined to the surface, mechanical cleaning combined with judicious leaching can reduce them to <1% of the total sample. The corresponding errors, which can now be specified, are often no greater than those associated with the statistics of counting.
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Шайдуллин, Khasan Shaydullin, Шайхов, Marsel Shaykhov, Еров, Yuriy Erov, Бабченко, and Vasiliy Babchenko. "INNOVATIVE TECHNOLOGIES AND TECHNIQUES INTRODUCTION EXPERIENCE FOR CULTIVATION AND POST-HARVEST HANDLING OF GRAIN AND SEEDS." Vestnik of Kazan State Agrarian University 9, no. 1 (September 7, 2014): 54–59. http://dx.doi.org/10.12737/3808.
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This study discusses a plant breeding and seed system recovery. According to the 2013 information, over 3000 seeders with colters of strip cropping were upgraded, which worked in 64 regions of the country. Simultaneously with the work on the modernization of the seeders for strip cropping, Russian Institute of Mechanization together with LLC “Tekhtsentr Laishevo” and “KhaRaSha” developed a design specification on the universal seeder SUZT 4of strip cropping with 4 meter width and a design specification on unified with it breeding and farming seeder SFS -2 with 2 meter wide. The pilot seeder SUZT-4 was designrd in LLC “KhaRaSha” and in 2012 it was successfully held acceptance tests with the recommendation on production at the Kirov Machine Testing Station. This seeder is designed for strip sowing of cereals, legumes, small-seeded crops and grass with simultaneous application of mineral fertilizers, as well as for early spring narrowband sowing of sparse winter crops and perennial grasses and subsurface mineral fertilizers plant nutrition. In 2013 there have manufactured a pilotmachine of breeding and farming seeder SFS-2 and it was transferred to Machine Testing Station for carrying out acceptance tests. The speeding up the implementing these seeders allow to carry out technological operation of planting crops in a highly effective stripping way with a significant increase of productivity and with high quality seeds. On spring wheat crops, where the seeds were prepared by car SMVO and sowing performed by seeders with ODA colters of strip cropping, the field germination ranged was from 92.5 to 95.6%, which is 4.5-8.1% higher, than seeds, obtained without isolation of their specific weight and drill sowing by double disc coulters. As a result, the higher harvest is formed by 8-10 centner per hectare and more. Additional 1.0 million tons of crops were reaped from improved seeds quality. Thus, the use of universal seeders with single disc - hoe colters and seed-crop cleaning machines SMVO is the most affordable way to increase the crops yield and seed quality for all farms. Key words: selection and seed-farming, Seed-growers association, seed-crop cleaning machine, processing of grain and seed, a seeder with disc-hoe colters, strip cropping .
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Miller-Willis, Kelsey L., Mini Thomas, and Victor C. Joe. "70 Chlorhexidine Gluconate for Burn Wound Cleansing: Reduction in Multi-drug Resistant Organism Acquisition." Journal of Burn Care & Research 41, Supplement_1 (March 2020): S45—S46. http://dx.doi.org/10.1093/jbcr/iraa024.074.
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Abstract Introduction Daily wound care is an important part of burn wound management to help prevent infection. Literature suggests that daily Chlorhexidine Gluconate (CHG) bathing can reduce the risk of acquiring Multi-Drug Resistant Organisms (MDRO). The purpose of this study was to identify change in overall MDRO acquisition in the Burn Unit with the addition of a 1% CHG solution for wound care to the CHG bathing protocol for burn patients. Methods Prior to March 2018, routine bathing and wound care involved use of CHG-incompatible antibacterial soap and water followed by 2% chlorhexidine gluconate cloths to intact skin. In March 2018, the bathing protocol changed, in consultation with the hospital’s infection prevention program, to involve a 1% CHG solution for burn wounds followed by 2% CHG cloths to intact skin in order to prevent the loss of protective residual CHG due to rinsing with CHG-incompatible soap and water. A solution of 1% CHG was chosen by staff as an acceptable concentration for wound bathing. Adherence was measured through review of daily documentation of bathing in the electronic medical record. Incidences of burn unit-attributable hospital-onset MDRO cultures were reviewed for the following periods: Baseline (Aug 2016-Aug 2017), Phase-In (Sept 2017 – Aug 2018) and Post-Implementation (Sept 2018 – Aug 2019). Results Adherence was >85% throughout the intervention period. No adverse events were noted. Incidences of hospital-onset burn unit MDROs during the following time periods were: 22 cases (Baseline), 15 cases (Phase-In), and 10 cases (Post-Implementation). The most common organisms in the baseline period were Extended-Spectrum b-Lactamase (ESBL) Escherichia coli, MRSA, and Multi Drug Resistant Pseudomonas; and post-implementation, the most common organisms were: MRSA and MDR-Pseudomonas. Conclusions A change to a 1% CHG solution for rinsing burn wounds in the setting of 2% CHG cloths to intact skin was well tolerated and associated with a decline in MDRO acquisition attributable to the burn ICU in the one-year post implementation. Applicability of Research to Practice The use of a 1% CHG solution for burn wounds may help prevent MDRO acquisition in the highly susceptible and unique burn population.
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Wigler, Ronald, Tal Koren, and Igor Tsesis. "Evaluation of Root Canal Cleaning and Shaping Efficacy of Three Engine-driven Instruments: SafeSider, ProTaper Universal and Lightspeed LSX." Journal of Contemporary Dental Practice 16, no. 11 (2015): 910–14. http://dx.doi.org/10.5005/jp-journals-10024-1780.
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ABSTRACT Aim To compare the cleaning effectiveness and shaping ability of SafeSider, ProTaper Universal and Lightspeed rotary instruments during the preparation of curved root canals in extracted human teeth. Materials and methods A total of 63 roots with curved root canals were divided into three groups. Canals were prepared using SafeSider, ProTaper Universal or Lightspeed LSX. Using pre- and post-instrumentation radiographs, straightening of the canal curvatures and loss of working length were determined with a computer image analysis program. The amounts of debris at the apical 5 mm were quantified on the basis of a numerical evaluation scale. The data were analyzed statistically using the two-way analysis of variance (ANOVA). Results There was significantly more transportation among the Lightspeed LSX group compared to the SafeSider and ProTaper Universal groups only at the 4 mm level (p < 0.05). The ProTaper Universal instruments performed significantly faster than other groups. No significant differences were observed between the three engine-driven instruments with regards to debris removal. Conclusion SafeSider, ProTaper Universal and Lightspeed LSX rotary instruments maintained the original canal curvature well at the apical 3 mm and were safe to use. No difference was found in cleaning efficacy and none rendered the apical part of the canal free of debris. Clinical significance SafeSider, ProTaper Universal and Lightspeed LSX rotary instruments are safe to use in curved root canals. How to cite this article Wigler R, Koren T, Tsesis I. Evaluation of Root Canal Cleaning and Shaping Efficacy of Three Engine- Driven Instruments: SafeSider, ProTaper Universal and Lightspeed LSX. J Contemp Dent Pract 2015;16(11):910-914.
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Kim, Seongil, Taeyoung Chae, Yongwoon Lee, Won Yang, and Sungho Hong. "Performance Evaluation of a Novel Thermal Power Plant Process with Low-Temperature Selective Catalytic Reduction." Energies 13, no. 21 (October 23, 2020): 5558. http://dx.doi.org/10.3390/en13215558.
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We present the concept of a novel thermal power plant process in conjunction with low-temperature selective catalytic reduction (SCR). This process can be employed to achieve modern standards for NOx emissions and solve problems related to post-gas cleaning processes, such as thermal fatigue, catalyst damage, and an increase in differential pressure in the boiler. Therefore, this study is aimed at evaluating the performance of a novel flue-gas cleaning process for use in a thermal power plant, where a low-temperature SCR is implemented, along with the existing SCR. We developed a process model for a large-scale power plant, in which the thermal power plant was divided into a series of heat exchanger block models. The mass and energy balances were solved by considering the heat transfer interaction between the hot and cold sides to obtain the properties of each material flow. Using the process model, we performed a simulation of the new process. New optimal operating conditions were derived, and the effects that the new facilities have on the existing process were evaluated. The results show that the new process is feasible in terms of operating stability and cost, as well as showing an increase in the boiler thermal efficiency of up to 1.3%.
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Pettit, Jared, Alman Law, Alex Brewer, and John Moore. "Substrate Temporary Bonding Supporting Post-Processing Applications." International Symposium on Microelectronics 2015, no. 1 (October 1, 2015): 1–7. http://dx.doi.org/10.4071/isom-2015-tha24.
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Post-processing applications are carried out on substrates while they are temporarily supported. This requires a simple adhesion process with easy removal without complex tooling or cleaning. Substrates include wafers, displays, or components, organic or inorganic, and may contain topography such as solder bumps. The applications may vary from backside processing of wafers, complete flexible circuit integration, or the stacking of packages. Simple processing may use green products as the detergent soluble DaeCoatTM 600-series, exhibiting thermal stability from 80°C to allow hot DIW debond, to over 200°C to support thermal processing. Temporary bonding may resist heat and chemicals for many steps or one major extreme. The DaeCoatTM 300-series of products are designed to resist thermal exposures >300°C for wafer operations with bumps or reach ≥400°C (DaeCoatTM 315) for flexible displays to allow casting of liquid polyimide (PI) [1]. The properties are consistent with the needs of electronics processes, providing outgas below 1% inert to fab chemicals, and most important, an adhesive force that is tuned to allow simple substrate removal (peeling, lifting, or chemical diffusion). Where discrete die or components require installing infrastructure to support stacking or fan-out designs, the thin and fragile substrate is securely held in place by simple dry bonding completed in seconds and later removed by similar peeling practices without observed residue. Such component practices enable encapsulation during bumping, permanent bonding, or physical vapor deposition (PVD) of electromagnetic and radio-frequency interference (EMI/RFI) shielding [2]. The success in these and other technologies depend upon the use of the proper adhesive but most importantly, the tuning of the adhesion force. Successful tuning depends upon many factors, including substrate surface energy, texture, and the bonding process. Daetec has created adhesives used in temporary bonding processes for nearly 20yrs, applying to multiple wafer types, OLED and TFT displays, printed electronics, solar, thinning down to 4um, and thermal resistance >600°C [3]. Our experience in creating solutions for these and other industry needs will be discussed as well as the criteria to temporarily support flexible and rigid substrates of all types, sizes, and shapes.
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Wei, Frank, Tomotaka Tabuchi, and Hideyuki Sando. "Plasma Dicing Process-Flows for Advanced Packaging Fabrications." International Symposium on Microelectronics 2017, no. 1 (October 1, 2017): 000215–23. http://dx.doi.org/10.4071/isom-2017-wa31_102.
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Abstract Comprehensive investigations were conducted on identifying integration efforts needed to adapt plasma dicing technology in BEOL pre-production environments. First, the authors identified a few suitable process flows. Within the plasma dicing process flows, laser grooving before plasma etching was shown to be a key unit process to control the resulting die sidewall quality. Significant improvement on laser grooving quality has been demonstrated. Through these efforts, extremely narrow kerfs and near ideal dies strengths were achieved on Si dies. The Bosch-etching based plasma dicing process generates fluorinated polymer residues both on the Si die sidewalls as well as under the topography overhangs on wafer surfaces, such as under the solder balls or micro-bumps. The fluorinated polymers in certain areas cannot be cleaned by an in-chamber post-treatments. Multiple wet chemistry-based cleaning methods demonstrated excellent process capability, and are compatible with plasma singulated dies-on-tape handling. Lastly, many methods exist for backside metal and under Si die-attach-film (DAF) separations. The authors highlighted recent processing results suitable for post-plasma dicing die separations of such film materials.