Journal articles: 'Conventional two-step process'

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Saimon, Nur Nazlina, Norzita Ngadi, Mazura Jusoh, and Zaki Yamani Zakaria. "A Two-Step SO3H/ICG Catalyst Synthesis for Biodiesel Production: Optimization of Sulfonation Step via Microwave Irradiation." Bulletin of Chemical Reaction Engineering & Catalysis 16, no. 1 (January 24, 2021): 63–75. http://dx.doi.org/10.9767/bcrec.16.1.9613.63-75.

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Conventional heating, a common method used for heterogeneous solid acid catalyst synthesis unknowingly consumes massive time and energy. In this study, acid catalyst was prepared through sulfonation process of incomplete carbonized glucose (ICG) via microwave-assisted technique to shorten the heating time and energy consumption. Optimization of the sulfonation process of ICG via microwave-assisted was carried out. Four-factor-three-level central composite design (CCD) was used to develop the design of experiments (DOE). Interaction between two factors was evaluated to determine the optimum process conditions. A quadratic model was proposed for prediction of biodiesel yield (Y) from palm fatty acid distillate (PFAD) and its conversion (C). The application of DOE successfully optimized the operating conditions for the two-step SO3H/ICG catalyst synthesis to be used for the esterification process. The optimized conditions of the best performing SO3H/ICG with maximum Y and C were at 7.5 minutes of reaction time, 159.5 mL of H2SO4 used, 671 rpm of stirring rate as well as 413.64 watt of power level. At these optimum conditions the predicted yield percentage and conversion percentage were 94.01% and 91.89%, respectively, which experimentally verified the accuracy of the model. The utilization of sulfonated glucose solid acid catalyst via microwave-assisted in biodiesel production has great potential towards sustainable and green method of synthesizing catalyst for biodiesel. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

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Karayannis, Vayos, Angeliki Moutsatsou, and Eleni Katsika. "Sintering lignite fly and bottom ashes via two-step versus conventional process." Science of Sintering 48, no. 3 (2016): 363–70. http://dx.doi.org/10.2298/sos1603363k.

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Wang, Xue Gang, and Xin Geng Li. "Transient Liquid Phase Bonding of T91 Steel Using Two-Step Heating Process." Advanced Materials Research 712-715 (June 2013): 701–4. http://dx.doi.org/10.4028/www.scientific.net/amr.712-715.701.

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A novel two-step heating process, consisting of a short-time high temperature heating followed by isothermal solidification at a lower temperature, was used to transient liquid phase (TLP) bond T91 steel. The interface morphology of the joint was investigated and compared with that of conventional TLP bond made at a constant bonding temperature. The results show that the two-step heating process produces a non-planar interface at the initial stage, which is different from the planar interfaces associated with conventional heating process. No interface can be found in the final joint by two-step heating process, however, a planar interface still exists in the final conventional TLP bond. Therefore, the bending ductility of the joint is dramatically improves by the two-step heating process, and the joint properties are similar to that of base metal.

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Costa, Fabrício, Glauberto Leilson Albuquerque, Luiz Felipe Silveira, Carlos Valderrama, and Samuel Xavier-de-Souza. "Variance-Triggered Two-Step GPS Acquisition." Sensors 19, no. 14 (July 19, 2019): 3177. http://dx.doi.org/10.3390/s19143177.

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The acquisition is the most time-consuming step performed by a Global Navigation Satellite System (GNSS) receiver. The objective is to detect which satellites are transmitting and what are the phase and Doppler frequency shift of the signal. It is the step with the highest computational complexity, especially for signals subjected to large Doppler shifts. Improving acquisition performance has a large impact on the overall performance of the GNSS reception. In this paper, we present a two-step Global Positioning System (GPS) acquisition algorithm whose first step performs an incremental correlation to find a coarse pair of phase and frequency and the second step, triggered by the variance of the largest correlation values, refines the first step. The proposed strategy, based on the conventional time-domain serial algorithm, reduces the average execution time of the acquisition process to about 1/5 of the conventional acquisition while keeping the same modest logic hardware requirements and slightly better success and false-positive rates. Additionally, the new method reduces memory usage by a factor that is proportional to the signal’s sampling frequency. All these advantages over conventional acquisition contribute together to significantly improve the overall performance and cost of GPS receivers.

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Dakre, Vinayak, D. R. Peshwe, S. U. Pathak, and Ajay Likhite. "TEM Analysis of Austempered Ductile Iron Processed Through Conventional and Two-Step Austempering Process." Transactions of the Indian Institute of Metals 72, no. 4 (January 5, 2019): 911–17. http://dx.doi.org/10.1007/s12666-018-1549-8.

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Aoki, Nobuhiro, and Mitsuo Kawase. "Development of High-Performance Thermophilic Two-Phase Digestion Process." Water Science and Technology 23, no. 7-9 (April 1, 1991): 1147–56. http://dx.doi.org/10.2166/wst.1991.0566.

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Anaerobic digestion of anaerobic sewage sludge leads to the generation of methane gas and reduction of the sludge volume. Because conventional digestion requires a long time, the digestion facilities must be large. We studied decomposing volatile suspended solids (VSS) in sewage sludge, capacitating high acid generation rates and a high-speed methane evolution reactor to reduce retention time for anaerobic digestion. We also studied how to increase VSS reduction ratio by using bio-technology. The high-performance thermophilic two-phase digestion (HPTTD) process is proposed as a innovative digestion system which has high-rate reducing and high-ratio reduction of volatile suspended solids in sewage sludge. This thermophilic digestion process consists of sludge conditioning, acidification and methanation steps. In the sludge conditioning step, sewage sludge is conditioned with thermal treatment and dosed with a protolytic enzyme. In the next step, acidification, acid fermentation is carried out at 70°C; this temperature is higher than that of conventional fermentation (conventional thermophilic digestion process: 55°C). In the methanation step an anaerobic fixed-bed reactor is used. In the digestion experiments using excess sludge, we obtained a 30% higher VSS reduction ratio (78% at HPTTD process) than that of conventional mesophilic digestion,

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Bauer, R. F. "A Two-Step Emulsion Polymerization Process Catalyzed by an Organic Diperoxide." Rubber Chemistry and Technology 77, no. 4 (September 1, 2004): 776–90. http://dx.doi.org/10.5254/1.3547851.

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Abstract An emulsion polymerization process is described which consists of consecutively polymerizing at least two olefinic monomers using an organic diperoxide with two independently functioning peroxy groups, namely 2,5-dimethyl-2-t-butylperoxy-5-hydroxy hexane. In the first polymerization step, the hydroperoxide group is activated by a redox reaction at low temperatures without decomposing the t-butyl peroxide portion of the initiator molecule. After charging fresh monomer, the t-butyl peroxide can then be thermally activated to initiate a second-stage polymerization reaction. This polymerization process employs conventional emulsion polymerization technology. It yields polymeric product with unique physical properties. Polymers with butadiene monomer in the first polymerization step, followed by styrene polymerization in the second step, resemble SBS tri-block polymers. They are thermoplastic, highly resilient and of good strength at high ultimate elongations. The consecutive polymerization of butadiene and acrylonitrile yields elastomers with a superior balance of low-temperature flexibility and resistance to swelling in organic solvents, when compared with random NBR copolymers of equivalent chemical composition. Combinations of butadiene and styrene in the first polymerization stage followed by styrene/acrylonitrile polymerization in the second, yield transparent ABS polymers with superior low-temperature impact resistance. Reference is also made to the polymerization of additional vinyl monomers.

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Fang, Jian, Xiao Hui Wang, and Long Tu Li. "Enhanced Performance of Alkaline Niobate-Based Ceramics Manufactured by Two-Step Sintering." Key Engineering Materials 512-515 (June 2012): 372–76. http://dx.doi.org/10.4028/www.scientific.net/kem.512-515.372.

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In this paper, a typical Li- and Ta/Sb- modified alkaline niobate-based ceramics are prepared by conventional sintering and two-step sintering respectively. The ceramics sintered by two-step sintering exhibit better electrical properties than the samples prepared by conventional sintering. The related mechanisms are also discussed in terms of phase-structures and microstructures. Results show that two-step sintering can restrain the volatilization of alkali elements and compositional segregation during the process of sintering dense alkaline niobate-based ceramics, and enhance the electrical properties accordingly. Therefore, two-step sintering is a promising approach to achieve high performance alkaline niobate-based ceramics.

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Magnani, Giuseppe, Giuliano Sico, and Alida Brentari. "Two-Step Pressureless Sintering of Silicon Carbide-Based Materials." Advances in Science and Technology 89 (October 2014): 70–75. http://dx.doi.org/10.4028/www.scientific.net/ast.89.70.

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Pressureless sintering of silicon carbide powder requires addition of sintering aids and high sintering temperature (>2100°C) in order to achieve high sintered density (>95% T.D.). The high sintering temperature normally causes an exaggerated grain growth which can compromise the mechanical properties. Two-step sintering (TSS) can be used to overcome this problem. By this method, high sintered density is obtained avoiding the grain growth associated to the last step of the sintering. Two-step sintering was successfully applied to different commercial silicon carbide powders with different sintering mechanism: solid-state and liquid-phase sintering. In both cases the sintering temperature was set nearly 100 °C below the temperature conventionally required. Microstructures of samples obtained by TSS and conventional sintering (CS) processes were compared. TSS-SiC showed finer microstructure consisted of equiaxed grains with very similar density. The beneficial effects of the two-step sintering process were more evident in the solid state sintering. In this case sintered density higher than 98% was achieved with T<2000 °C.

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Eo, Jae Dong, Jingyu Kim, Yongsug Jung, Jong-Hang Lee, and Wook Bae Kim. "Effects of Two-Step Anodization on Surface Wettability in Surface Treatment of Aluminum Alloy." Korean Journal of Metals and Materials 59, no. 2 (February 5, 2021): 73–80. http://dx.doi.org/10.3365/kjmm.2021.59.2.73.

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Industrial anodizing of aluminum alloys is widely employed for various products, to improve corrosion and contamination protection as well as aesthetic appearance. At the same time, nanostructure fabrication using highly ordered porous aluminum oxides has been increasingly investigated in academic research for diverse micro-/nano applications. This approach is based on two-step anodization with limited process conditions, such as extended process time and low temperature. In this study, two-step anodizing was employed to anodize hairline-finished Al 1050 with sulfuric acid considering industrial processing conditions. The method is particularly suited for anodized products that require post-processing such as printing, dyeing and/or bonding. Porous anodized layers that were fabricated using conventional single anodizing, and twostep anodizing under identical processing conditions were compared. Variations in porosity, pore diameter, and inter-pore distance were examined in relation to the anodizing parameters, such as temperature and voltage. The results showed that two-step anodizing caused an increase in all measured pore-related measurements, and produced a much more uniform porous layer than the conventional anodizing process. Water contact angles were evaluated on the anodized surface of the previously machined hairline specimen. It was found that the water contact angles clearly decreased on the surfaces treated by two-step anodization, compared to the conventional anodizing process.

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Lai, Meiling, Shengliang Peng, Xi Yang, and Lin Zhou. "Fast Two-Step Energy Detection for Spectrum Sensing." Journal of Electrical and Computer Engineering 2015 (2015): 1–6. http://dx.doi.org/10.1155/2015/591627.

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Spectrum sensing is one of the key tasks in cognitive radio. This paper proposes a fast two-step energy detection (FED) algorithm for spectrum sensing via improving the sampling process of conventional energy detection (CED). The algorithm adaptively selectsN-point or 2N-point sampling by comparing its observed energy with prefixed double thresholds, and thereby is superior in sampling time and detection speed. Moreover, under the constraint of constant false alarm, this paper optimizes the thresholds from maximizing detection probability point of view. Theoretical analyses and simulation results show that, compared with CED, the proposed FED can achieve significant gain in detection speed at the expense of slight accuracy loss. Specifically, within high signal-to-noise ratio regions, as much as 25% of samples can be reduced.

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Yang, M., Y. Zhang, R. Qi, K. Uesugi, and H. Myoga. "Improved O3/H2O2 oxidation process for wastewater reclamation." Water Science and Technology 43, no. 10 (May 1, 2001): 311–18. http://dx.doi.org/10.2166/wst.2001.0649.

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A continuous two step O3/H2O2 oxidation system, in which the waste gas from the former reactor was reused in the latter step with an ejector, was established for the purpose of wastewater reclamation in electronics industries. ORP monitor was combined into the system to obtain the optimum ratio of H2O2 to O3 by automatically adjusting the dosage of H2O2, and ion exchange resin was used for removing organic acids formed during oxidation. The effectiveness of the O3/H2O2 oxidation system for TOC removal was investigated under various conditions by using IPA, DMSO, and NMP as model substances. The optimum H2O2/O3 for oxidizing IPA was in a range above 0.15, and it increased with the increase of O3 dose. A sudden drop of ORP from ca. 800 mV to a little more than 200 mV was observed when H2O2/O3 was approaching the optimum point from the lower end. An ORP between 250 mV and 300mV or 800 mV and 900 mV was proper for H2O2/O3 control. The treatability of the model substances was in an order of IPA<<DMSO<NMP, being consistent with the magnitude of the energy of the highest occupied molecular orbital (eHOMO). The two step treatment system developed in this study was found to be more efficient than the conventional single step system. With the help of H2O2 dosing control and two step treatment using waste O3, the system could save about 40% O3 in comparison with the conventional O3/H2O2 oxidation process.

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Jeong, Suk Hoon, Suk Bae Joo, Ho Jun Lee, Boum Young Park, Hyoung Jae Kim, and Hae Do Jeong. "Two-Step Planarization of ECMP and CMP for MEMS Copper Patterns." Materials Science Forum 569 (January 2008): 117–20. http://dx.doi.org/10.4028/www.scientific.net/msf.569.117.

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Chemical mechanical polishing (CMP) has been used as planarization process in the fabrication of semiconductor devices. The CMP process is required to planarize the overburden film in an interconnect process by high relative velocity between head and platen, high pressure of head and chemical effects of an aqueous slurry. But, a variety of defects such as dishing, delamination and metal layer peering are caused by CMP factors such as high pressure, pad bending and strong chemical effect. The electrical energy of the electro-chemical mechanical planarization (ECMP) dissolves copper (Cu) solid into copper ions electrochemically in an aqueous electrolyte. The dissolved copper complex layer or passivation layer is removed by the mechanical abrasions of polishing pad and abrasive. Therefore the ECMP process realizes low pressure processing of soft metals to reduce defects comparing to traditional CMP process. But, if projected metal patterns were removed and not remained on whole wafer surface in final processing stage, Cu layer could not be removed by ECMP process. The two-step process consists of the ECMP and the conventional CMP used in micro patterned Cu wafers. First, the ECMP process removed several tens 'm of bulk copper on Cu patterned wafer within shorter process time than the Cu CMP. Next, residual Cu layer was completely removed by the Cu CMP under low pressure. Total time and process defects are extremely reduced by the two-step process.

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Scholz, David, Jingwei Xie, Oliver Kröcher, and Frédéric Vogel. "Mechanochemistry-assisted hydrolysis of softwood over stable sulfonated carbon catalysts in a semi-batch process." RSC Advances 9, no. 57 (2019): 33525–38. http://dx.doi.org/10.1039/c9ra07668a.

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Kim, Jeong Min, Joong Hwan Jun, Ki Tae Kim, and Woon Jae Jung. "Effects of Isothermal Heating Process and Rare Earth Elements Addition on the Mechanical Properties of Semi-Solid Formed Mg-5%Zn Alloys." Materials Science Forum 544-545 (May 2007): 279–82. http://dx.doi.org/10.4028/www.scientific.net/msf.544-545.279.

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Two-step isothermal heating and conventional one-step heating processes were used to produce the semi-solid slurry of Mg-5%Zn-0.5%Zr alloys with and without 1%RE. It was found that the slurry with better semi-solid characteristics could be fabricated by the two-step heating compared to the conventional process. Only the small amount of RE addition to the Mg-5%Zn- 0.5%Zr alloy was observed to reduce the solid particle size of slurry significantly and to improve the tensile strength at 150oC, probably owing to Mg-Zn-RE phase with a high thermal stability.

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Legro, Jeffrey W. "Culture and Preferences in the International Cooperation Two-Step." American Political Science Review 90, no. 1 (March 1996): 118–37. http://dx.doi.org/10.2307/2082802.

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Rational choice analyses of international cooperation have slighted the effect of state preference formation and the influence of cultural forces in that process. This article addresses these gaps by developing an explanation that specifies how organizational cultures of bureaucracies shape state aims and international outcomes. This approach is evaluated in a set of least likely cases—decisions on the use of force in war—where the conventional wisdom expects external material, not internal cultural, concerns to dominate. Before World War II, countries agreed to limit the use of three types of warfare, but during that conflict mutual restraint was maintained in only one. I show how this variation is best understood as a product of state preference dynamics, shaped largely by the collective beliefs and customs of military services. This result suggests ways to rethink the use of the preferences-interaction model and the role of cultural factors in that framework.

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Feldthusen, Jesper, Béla Iván, Axel H. E. Müller, and Jørgen Kops. "Synthesis of linear and three-arm star tert-chlorine-telechelic polyisobutylenes by a two-step conventional laboratory process." Macromolecular Rapid Communications 18, no. 5 (May 1997): 417–25. http://dx.doi.org/10.1002/marc.1997.030180509.

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Roces, Susan A., Raymond Tan, Francisco Jose T. Da Cruz, Shuren C. Gong, and Rison K. Veracruz. "Methanolysis of Jatropha Oil Using Conventional Heating." ASEAN Journal of Chemical Engineering 11, no. 1 (August 5, 2011): 41. http://dx.doi.org/10.22146/ajche.50043.

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Studies were carried out on the transesterification, also called methanolysis, of oil from the Jatropha curcas L. with methanol using conventional heating for the production of biodiesel. All reactions were carried out in a batch-stirred reactor and in the subsequent separation and purification stages. The high free-fatty acid (FFA) level of Jatropha oil was reduced to less than 1% by a two-step process. The first step was carried out with 12% w/w methanol-to-oil ratio in the presence of 1% w/w HCl as acid catalyst in a 2h reaction at 343K. The second step was carried out with variable parameters: temperatures at 318K and 333K, initial catalyst concentrations at 0.5% and 1.5%, methanol:oil molar ratios at 4:1 and 6:1, and reaction times at 1h and 2h. Gas chromatography analysis was used to determine the fatty acid profile of crude Jatropha oil. Methanolysis of Jatropha oil used the catalysts NaOH and KOH. The high FFA level of Jatropha oil was reduced from 6.1% to 0.7% after the first step process. The highest yield of fatty acid methyl esters (FAME), however, was achieved at 92.7% in 2h at 4:1 methanol:oil molar ratio, 1.5% w/w KOH, and 333K reaction temperature. This method produced biodiesel that met ASTM’s biodiesel standards. Results showed a density of 0.8g/ml that is within 0.86–0.9kg/l standard range and a kinematic viscosity of about 4.1cSt that is within 2–4.5cSt standard range. The flash point of the biodiesel samples fell between 169oC and 179oC while the cloud point averaged at 6oC.

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Chen, Yan-Ren, Hsien-Wen Chao, Hung-Chun Hsu, Cheng-Hsuan Chan, Wei-Hsiang Lin, Che-Wei Tsai, and Tsun-Hsu Chang. "A Two-Step Microwave Annealing Process for PAN Pre-Oxidation through a TM-Mode Cavity." Polymers 13, no. 9 (May 3, 2021): 1476. http://dx.doi.org/10.3390/polym13091476.

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A novel microwave annealing system and a specific processing condition are proposed for the pre-oxidation of carbon fiber. The microwave annealing system consists of a TM-mode resonant cavity and a silicon carbide (SiC) susceptor. The TM-mode cavity enhances the electric field at the center. The SiC susceptor absorbs part of the microwave energy and converts it to heat. The enhanced fields and the SiC susceptor provide both nonthermal and thermal treatments for fibrous materials with various dielectric properties. Furthermore, a two-step microwave annealing process is used to oxidize polyacrylonitrile (PAN) fiber. The scanning electron microscopy (SEM) images, differential scanning calorimetry (DSC), and X-ray diffraction (XRD) results support the theory that the microwave annealing can achieve a high aromatic index of 66.39% in just 13 min, 9 times faster than the traditional processing time. The results of the Raman spectra also illustrate that the sheath-core factor of the microwave-heated specimen is closer to one than that of the conventional furnace-heated type, which agree with the images of the cross-section area.

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Ali, Naser, Joao A. Teixeira, and Abdulmajid Addali. "Aluminium Nanofluids Stability: A Comparison between the Conventional Two-Step Fabrication Approach and the Controlled Sonication Bath Temperature Method." Journal of Nanomaterials 2019 (October 27, 2019): 1–9. http://dx.doi.org/10.1155/2019/3930572.

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This study investigates the shelving stability of dispersed aluminium nanoparticles in water mixtures fabricated by the conventional and the controlled bath temperature two-step methods. The nanofluids were prepared with water of pH 9 and nanoparticles of 0.1–1.0 vol.%. A bath type ultrasonicator was employed for dispersing the nanoparticles into the base fluid. The sonication process, for all as-prepared samples, lasted for 4 hours and was either device bath temperature uncontrolled or controlled in the range of 10–60°C. Furthermore, the stability of the as-produced nanosuspensions was evaluated using the sedimentation photograph capturing method by capturing images at equal intervals of time for 12 hours then analysing the data based on the sample sedimentation height ratios. It was found that the sedimentation behaviour of the nanofluids fabricated via the controlled temperatures of less than 30°C was of dispersed sedimentation type, while those produced by the conventional method and the fixed temperatures of 30°C and higher were of flocculated sedimentation type. In addition, increasing the controlled sonication temperature has shown to increase the settling process of the sediments. Moreover, the rise in nanoparticle concentration was seen to reduce the variation in sedimentation height ratio between the fixed temperature samples. A comparison between the two fabrication methods has shown that the 30°C nanofluids had better short- and long-term stability than the conventionally produced suspensions.

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Savin, Alexandru, Alexandru Floca, Mihai Trifănescu, Nicolae Ionescu, and Aurelian Vişan. "Development of Modeling Process in Rapid Freeze Prototyping." Applied Mechanics and Materials 760 (May 2015): 117–22. http://dx.doi.org/10.4028/www.scientific.net/amm.760.117.

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Through rapid prototyping [1,2] it can be achieved both conceptual models: the final prototypes and functional parts in less time than with conventional technologies. The author of this paper shows the dependence of the diameter of liquid nitrogen spray nozzles according to the diameters of the water spray nozzle, a factor that is important in determining the amount of liquid nitrogen required to freeze the drop of water. Regarding the deposited layer thickness estimation, the author presented two theoretical models of contact between water droplets, which depend on the step between two consecutive drops of water.

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Koo, Yang Mo, Kyu Hwan Oh, and Dong Nyung Lee. "Thermomechanical Treatment for Enhancing Deep Drawability of Copper-Bearing Bake Hardening Steel." Materials Science Forum 706-709 (January 2012): 2634–39. http://dx.doi.org/10.4028/www.scientific.net/msf.706-709.2634.

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A two-step rolling-annealing process has been developed to increase the <111>//ND (γ fiber) component in the recrystallization texture of a copper-bearing bake hardening steel. The two step process comprises the first rolling by a low reduction in thickness and subsequent annealing at 780°C, followed by the second rolling by a high reduction and subsequent annealing at 780°C. The first rolling process aims at seeding the γ fiber oriented grains, so that they can grow at the expense of differently oriented grains developed in the second rolling process. In this way the density of γ fiber component in the recrystallization texture of the bake hardening steel much increases compared with that in the conventional one-step rolling-annealing process.

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Shim, Jae Hyun, J. H. Ok, Hyoung Jin Choi, H. S. Koo, and Beong Bok Hwang. "A Process Sequence Design of Multi-Step Cold Extrusion Process for Hollow Parts." Materials Science Forum 475-479 (January 2005): 4195–98. http://dx.doi.org/10.4028/www.scientific.net/msf.475-479.4195.

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Conventional multi-step extrusion processes with solid billet are examined by the rigid-plastic finite element method in order to provide criteria for new process sequence for hollow parts. Two examples are taken for the analyses such as the current three-stage cold extrusion process for a hollow flange part and five-stage process for manufacturing an axle housing. Based on the results of simulation of the current three-stage and five-stage manufacturing processes, new design strategy for improving the process sequences is developed simply by replacing the initial billet from solid to hollow one. The developed new process sequences are applied for simulation by FEM and they are compared with the existing processes to confirm the usefulness of new process sequences with hollow initial billets. The results of simulation show that the newly proposed process sequences with hollow billet instead of solid one are more economical way to manufacture required parts, respectively.

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Liao, Shun Sing, Yueh Chin Lin, Chuan Lung Chuang, and Edward Yi Chang. "Efficiency Enhancement of Multicrystalline Silicon Solar Cells by Inserting Two-Step Growth Thermal Oxide to the Surface Passivation Layer." International Journal of Photoenergy 2017 (2017): 1–6. http://dx.doi.org/10.1155/2017/9503857.

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In this study, the efficiency of the multicrystalline was improved by inserting a two-step growth thermal oxide layer as the surface passivation layer. Two-step thermal oxidation process can reduce carrier recombination at the surface and improve cell efficiency. The first oxidation step had a growth temperature of 780°C, a growth time of 5 min, and with N2/O2 gas flow ratio 12 : 1. The second oxidation had a growth temperature of 750°C, growth time of 20 min, and under pure N2 gas environment. Carrier lifetime was increased to 15.45 μs, and reflectance was reduced 0.52% using the two-step growth method as compared to the conventional one-step growth oxide passivation method. Consequently, internal quantum efficiency of the solar cell increased 4.1%, and conversion efficiency increased 0.37%. These results demonstrate that the two-step thermal oxidation process is an efficient way to increase the efficiency of the multicrystalline silicon solar cells.

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Yao, Pan Pan, and Qiang Wang. "Investigation on Hole Punching Process with Combined Punch to Improve Surface Quality during the Materials Forming Process." Key Engineering Materials 737 (June 2017): 77–82. http://dx.doi.org/10.4028/www.scientific.net/kem.737.77.

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The present work shows the viability of a combined punch that makes possible to perform a hole punching followed by a hole burnishing in only one operation. The advantage of this combined punch is forming processes in only one process on medium thickness plate. In this work were tested two different configurations of punches which one of them is the conventional punch and another is a new structure of combined punch. The new structure of combined punch is added the step and inclined edge at the cutting edge on the basis of conventional punch. They are made of the same materials that are Cr12MoV. The new structure of combined punch and the conventional punch are studied by using numerical simulation and experimental research in this paper. During the materials forming process of hole punching, the simulation software ANSYS is used to simulate. The YZ32-100 Hydraulic press with nominal and the self-made die sets and the thick of 16mm Q235 sheet metal is selected in this experiment. The analysis of the obtained results showed that the hole surface quality of combined punch is superior to the conventional punch. It is prove that the new structure of combined punch can improve quality of punching.

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Mustafa, Mohd Faris, Noor Asma Fazli Abdul Samad, Kamarul Asri Ibrahim, Norazana Ibrahim, and Mohd Kamaruddin Abd Hamid. "Energy Efficient Distillation Columns Design for Retrofit NGLs Fractionation Process." Advanced Materials Research 1113 (July 2015): 667–73. http://dx.doi.org/10.4028/www.scientific.net/amr.1113.667.

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Distillation is the primary separation process widely used in the industrial chemical process. Although it has many advantages, the main drawback is its large energy requirement, which may significantly influence the overall plant profitability. However, the large energy requirement of these processes can be systematically reduced by using driving force and energy integration methods. This paper presents a methodology for designing energy efficient distillation columns systems based on those two methods. Generally, the proposed methodology consists of four hierarchical steps. In the first step, the system of distillation columns for multicomponent separation is designed based on the conventional distillation column design (shortcut) method. Then, the conventional distillation columns systems design is improved in terms of energy saving by using driving force method in the second step. It is expected in the third step that the distillation columns systems design can be further improved in terms of energy saving by using energy integration method. Finally, the distillation columns systems design is evaluated in terms of economic performance. The simulation results by using Aspen HYSYS have shown that the driving force sequence by using shortcut method for NGLs has energy savings with 55% reduction compared to a direct method with shortcut method. It can be verified that the proposed methodology has the capability in designing energy efficient distillation columns in an easy, systematic and practical manners.

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Liu, Da Hai, Jun Chu Li, and Chun Chang. "Experimental Investigations on Electromagnetically Assisted Corner-Fill Performance of AA5052 Sheets." Advanced Materials Research 538-541 (June 2012): 1179–82. http://dx.doi.org/10.4028/www.scientific.net/amr.538-541.1179.

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To establish the efficacy of electromagnetically assisted sheet metal stamping (EMAS), the corner-fill ability of AA5052 sheets specified in conventional deep drawing was experimentally demonstrated and evaluated within a two-step EMAS process. First, conventional axisymmetric deep drawing was conducted to make a cylindrical cup with a rough-shaped bottom corner. The second step utilized a shaped coil to force the pre-formed cup into the die cavity, and the related electromagnetically assisted corner-fill performance was investigated. Experimental results show that the ideal of hybrid stamping-EMF sequence can successfully solve the formability problem involved in conventional stamping. During electromagnetically assisted corner-fill process, the deformation dispersion effect of dynamic phenomenon works remarkably on the fully deformed sheets, which will inhibit local instability of deformation and thus enhance materials formability.

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Bakar, Suliana Abu, Suzana Yusup, Murni Melati Ahmad, Armando T. Quitain, Mitsuru Sasaki, Motonobu Goto, Yoshimitsu Uemura, and Junaid Ahmad. "Comparative Study on Two-Step Fatty Acid Methyl Ester (FAME) Production from High FFA Crude Palm Oil Using Microwave Technique and Conventional Technique." Advanced Materials Research 917 (June 2014): 87–95. http://dx.doi.org/10.4028/www.scientific.net/amr.917.87.

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The production of biodiesel from crude palm oil (CPO) using microwave technique is investigated and has been compared with conventional heating. Two-step biodiesel production process is applied to maximize the highest biodiesel yield in short reaction time using microwave method. Sulfuric acid (H2SO4) as acid catalysts is used in pre-treatment of feedstock by esterification process followed by potassium hydroxide (KOH) as base catalyst for transesterification process with low methanol to oil ratio. The main purpose of the pre-treatment process is to reduce the free fatty acids (FFA) content of CPO from higher value of FFA content (>6.8%) to a minimum level for biodiesel production (<1%). Esterification and transesterification is carried out in fully instrumented and controlled microwave reactor system to get higher yield in shorter time. This two-step esterification and transesterification process showed that the maximum conversion of palm biodiesel obtained is 95.1% with the process conditions of methanol-to-oil molar ratio of 6:1, reaction temperature 65oC, reaction time 15min, and 2% (wt/wt) KOH amount using microwave method compared to conventional heating where the palm oil methyl ester (POME) yield obtained is 81% at the same conditions. The result showed that, the biodiesel production using microwave technique proved to be a fast and easy route to get high yields of biodiesel.

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Ingarao, Giuseppe, Paolo C. Priarone, Francesco Gagliardi, Rosa di Lorenzo, and Luca Settineri. "Environmental Comparison between a Hot Extrusion Process and Conventional Machining Processes through a Life Cycle Assessment Approach." Key Engineering Materials 622-623 (September 2014): 103–10. http://dx.doi.org/10.4028/www.scientific.net/kem.622-623.103.

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Nowadays manufacturing technologies have to be evaluated not only for the technical features they can provide to products, but also considering the environmental perspective as well. As long as the technological feasibility of a given process is guaranteed, processes minimizing resources and energy consumption have to be selected for manufacturing. With respect to this topic, the research studies in the domain of metal processing technologies predominantly focus on conventional material removal processes as milling and turning. Despite some exceptions, many other non-machining technologies, such as metal forming processes, are still not well documented in terms of their energy and resource efficiency, and related environmental impact. In this paper, an environmental challenge between two traditional technologies is developed: the environmental performances of a partial hot extrusion process and of a turning processes are quantified and compared. A Life Cycle Assessment (LCA) approach is implemented to properly analyze the considered processes. The material production step and the manufacturing phase to obtain a simple axy-symmetric aluminum component is considered for the Life Cycle Inventory (LCI) data collection step. Besides, the material and consumables usage and the consumed electrical power are measured in order to quantify the energy consumption of the manufacturing phase. Further, the environmental impacts related to the manufacturing of the extrusion dies and of the turning process are included in the analysis. The paper presents an early step of a wider research project aiming at identifying the greenest technologies as functions of given product features.

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Takamizawa, Toshiki, Munenori Yokoyama, Keiichi Sai, Sho Shibasaki, Wayne W. Barkmeier, Mark A. Latta, Akimasa Tsujimoto, and Masashi Miyazaki. "Effect of Adhesive Application Method on the Enamel Bond Durability of a Two-Step Adhesive System Utilizing a Universal Adhesive-Derived Primer." Applied Sciences 11, no. 16 (August 20, 2021): 7675. http://dx.doi.org/10.3390/app11167675.

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This study aimed to evaluate the effect of the adhesive application method on the durability of the enamel bond and the thickness of the adhesive layer. A new-generation two-step universal adhesive system, G2-Bond Universal, and two conventional two-step adhesive systems were utilized. The shear bond strength to bovine enamel was measured after thermal cycling in both etch-and-rinse and self-etch modes. Fifteen specimens were divided into three groups as follows: Group I, wherein a strong air stream was applied over the bonding agent for 5 s; Group II, wherein a gentle air stream was applied over the bonding agent for 5 s; and Group III, which was prepared as in Group II, followed by the application of a second layer of the bonding agent and a gentle air stream for 5 s. The durability of the enamel bond and thickness of the tested adhesives were influenced by the application method in both etching modes. The application method used in Group II appeared to be most suitable in terms of the bonding of the adhesives to the enamel. The new-generation two-step self-etch adhesive, comprising a universal adhesive-derived primer and a hydrophobic bonding agent, showed superior bond performance to the conventional two-step adhesive systems.

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Versprille, A. I., B. Zuurveen, and Th Stein. "The A–B Process: A Novel two Stage Wastewater Treatment System." Water Science and Technology 17, no. 2-3 (February 1, 1985): 235–46. http://dx.doi.org/10.2166/wst.1985.0133.

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New acts on wastewater disposal demand for higher process stability and effluent quality. The A-B process, a novel two step treatment system, meets these requirements in a cost effective way. Five full-scale plants have been put in operation over the last two years. The objective of this paper is to give an outline of the features of the A-B system in the context of the results of these full-scale plants. In spite of the extreme high load, the A-stage can be operated at a high reduction rate and is stable. Variations in the organic load and pH- and toxic shocks are leveled out and a constant, mainly soluble effluent is supplied. This implicates a low sludge production in the B-stage. As a consequence higher overall reduction rates are obtained as compared to conventional processes at the same sludge load. Very low and stable final effluent concentrations are observed in all full-scale plants. Of special interest are the possibilities of upgrading existing conventional treatment facilities, at minor costs, by incorporating the A-B technology. The A-B process therefore can be considered as a very promising, cost effective alternative for both existing and new wastewater treatment plants in responding to the increasing effluent demands.

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Li, Qiu Ze, Lei Xu, Ji Xiao Song, Jing Han, Xing Min Huang, and Guang Ze Dai. "Influence of Three-Step Aging Heat Treatment on Properties of 7A04 Aluminum Alloy." Materials Science Forum 704-705 (December 2011): 645–49. http://dx.doi.org/10.4028/www.scientific.net/msf.704-705.645.

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Aiming at traditional peak aging of 7A04 Aluminum Alloy with high strength but low corrosion resistance, innovative gradually cooling three-step aging heat treatment process were designed, conventional mechanical properties and corrosion resistance of 7A04 aluminum after three kinds of aging treatments was studied through microstructure. The results show that compared with the traditional peak aging process, two gradually cooling three-step aging process is to improve materials tensile strength, plastic and impact toughness in different degrees. Meanwhile corrosion resistance of materials has improved significantly. And extension of low temperature aging time is conducive to the further improvement of strength.

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Park, Jong-Han, and Keun Park. "Development of Micropatterns on Curved Surfaces Using Two-Step Ultrasonic Forming." Micromachines 10, no. 10 (September 28, 2019): 654. http://dx.doi.org/10.3390/mi10100654.

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Nanoimprint lithography (NIL) is a micro/nanoscale patterning technology on thermoplastic polymer films, and has been widely used to fabricate functional micro/nanoscale patterns. NIL was also used to develop micro/nanoscale patterns on curved surfaces by employing flexible polymer stamps or micropatterned metal molds with macroscopic curvatures. In this study, two-step ultrasonic forming was used to develop micropatterns on a curved surface out of a flat metal stamp, by connecting ultrasonic imprinting and stretching processes. Ultrasonic imprinting was used to replicate functional micropatterns on a flat polymer film, using a flat ultrasonic horn and micropatterned metal stamps with prism and dot micropatterns. An ultrasonic stretching process was then used to form a curvature on the patterned film using a curved ultrasonic horn and a soft mold insert, to avoid damage to the pre-developed micropatterns. The ultrasonic horn was designed to have three different tip radii, and the resulting forming depth and curvature formation were investigated experimentally. As a result, three different curved surfaces containing two different micropatterns were obtained. The developed curved films containing micropatterns were then evaluated optically, and showed different optical diffusion and illumination characteristics according to the film curvature and micropattern type. These results indicate that the proposed technology can extend the functionality of conventional micropatterned products by imposing appropriate curvatures.

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Wu, Qiang, Jim P. Zheng, Mary Hendrickson, and Edward J. Plichta. "Dry Process for Fabricating Low Cost and High Performance Electrode for Energy Storage Devices." MRS Advances 4, no. 15 (2019): 857–63. http://dx.doi.org/10.1557/adv.2019.29.

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AbstractWe report a roll-to-roll dry processing for making low cost and high performance electrodes for lithium-ion batteries (LIBs). Currently, the electrodes for LIBs are made with a slurry casting procedure (wet method). The dry electrode fabrication is a three-step process including: step 1 of uniformly mixing electrode materials powders comprising an active material, a carbonaceous conductor and the soft polymer binder; step 2 of forming a free-standing, continuous electrode film by pressing the mixed powders together through the gap between two rolls of a roll-mill; and step 3 of roll-to-roll laminating the electrode film onto a substrate such as a current collector. Compared with the conventional wet slurry electrode manufacturing method, the dry manufactural procedure and infrastructure are simpler, the production cost is lower, and the process eliminates volatile organic compound emission and is more environmentally friendly, and the ability of making thick (>120µm) electrodes with high tap density results in high energy density of final energy storage device. A prototype LIBs of LiNi0.6Mn0.2Co0.2O2 (NMC622)/graphite also has 230 Wh/ kg energy density.

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Bassani, Andrea, Cecilia Fiorentini, Vellingiri Vadivel, Alessandro Moncalvo, and Giorgia Spigno. "Implementation of Auto-Hydrolysis Process for the Recovery of Antioxidants and Cellulose from Wheat Straw." Applied Sciences 10, no. 17 (September 3, 2020): 6112. http://dx.doi.org/10.3390/app10176112.

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Wheat straw is an easily affordable, cost-effective and natural source of antioxidants and cellulose, but its full potential is not yet utilized. In the present investigation, an auto-hydrolytic process was applied to recover both antioxidant phenolic compounds and cellulose from wheat straw. Two three-step acid/alkaline fractionation processes were applied differing for the first step: a conventional mild acid hydrolysis or an auto-hydrolysis. The liquors from the first step were analyzed for the recovery of antioxidants, while the final residues from the whole process were analyzed for cellulose yield and purity. The auto-hydrolysis process led to a higher yield in antioxidants but also in sugars (glucose and xylose) and sugar degradation products (5-HMF, 5-MF, furfural) than the acid hydrolysis process. The overall cellulose recovery (about 45% g/100 gcellulose wheat straw dm) and purity was comparable in the two processes; therefore, the auto-hydrolysis-based process could be recommended as a potentially more environmentally friendly process to recover antioxidants and cellulose from wheat straw for different applications. Finally, a first study on the optimization of hydrolysis step was provided from the point of view of improving the cellulose yield, monitoring the sugars release during both the acid hydrolysis and the auto-hydrolysis process.

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Banduka, Nikola, Aleksandar Aleksić, Nikola Komatina, Amanda Aljinović, and Danijela Tadić. "The prioritization of failures within the automotive industry: The two-step failure mode and effect analysis integrated approach." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 234, no. 12 (June 16, 2020): 1559–70. http://dx.doi.org/10.1177/0954405420926906.

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Traditionally, in the automotive industry, the risk posed by failures in manufacturing is based on the conventional process failure mode and effect analysis. The market changes, as well as limited financial resources dedicated to business improvement, induce the need for employment of advanced management tools. The rating of failures is derived from the research using the suggested fuzzy classification method based on the Pareto analysis. It is assumed that the classification criterion should be determined as the product of the overall product choice and the risk priority numbers given by applying the traditional process failure mode and effect analysis. All the uncertainties that exist in the problem under consideration are represented by linguistic expressions that are modeled on the interval type-2 triangular fuzzy numbers. The overall product choice is based on a fuzzy analytical hierarchy process with interval type-2 triangular fuzzy numbers. The execution of management initiatives based on the priority of failures can result in the improvement of the manufacturing process and overall business efficiency. The proposed model is tested using real-life data from a single vehicle manufacturer operating in the Western Balkans and representing a part of a global automotive supply chain.

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Browne, David J., M. Scanlan, and A. Bates. "Functionally Gradient Materials via a Casting Process Involving Partial Solidification." Solid State Phenomena 141-143 (July 2008): 349–54. http://dx.doi.org/10.4028/www.scientific.net/ssp.141-143.349.

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A novel technique for the production of functionally gradient materials, developed by the authors, is presented. The process is known as the Cast-Decant-Cast or CDC process, and involves a partial solidification step. This process takes expensive and time-consuming factors out of the production of functionally gradient materials by enabling utilisation of standard foundry equipment, and the process is carried out in a single multi-step casting operation. The CDC process involves simultaneous but separate melting of two alloys of different composition in order to produce a gradient in material properties. Details of the process are presented. It is shown that the outcome depends on partial local remelting and alloy mixing, which results in a gradual change or gradient between the first and second alloys in the as-cast condition, hence producing a functionally gradient material. The process has been adapted to conventional casting methods such as gravity casting and low pressure casting. It is the method of decanting the first material from the mould that differentiates the process variants. The decanting step for the low pressure method is controlled by pressure application and release on the molten alloys within their respective, but separate, sealed holding chambers. Decanting for the gravity casting method began as a physical inversion of the mould and is now at the point of autodecanting through careful design of an innovative gating system. The CDC process has been proven by means of metallographic study of microstructure to produce functionally gradient materials. Adapting the CDC process to conventional casting methods has made it a potentially commercially viable option for numerous applications. The results of recent research on the process are presented in summary form, including multi-alloy experiments, observations on the influence of timing and thermal control, and FGM manufacture using MMCs and joining dissimilar metals.

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Wekerle, J., M. Leuze, and K. Koch. "Virus Inactivating Effect of Anaerobic Mesophilic Digestion of Municipal Sludge with or without Different Preceding Types of Treatment." Water Science and Technology 17, no. 10 (October 1, 1985): 175–84. http://dx.doi.org/10.2166/wst.1985.0108.

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The effect of the conventional mesophilic anaerobic one-step digestion, and of two-phase processes with and without pre-pasteurisation and pasteurisation of the digested sludge on three non-enveloped viruses was investigated. Reovirus Type 1 and bovine Enterovirus (ECBO-LCR-4) were inactivated completely by the one-step mesophilic anaerobic digestion process with a mean hydraulic retention time (MHRT) of 20 days, as well as by the two-phase process with a MHRT of two days in the anaerobic pretreatment at 33°C or 20°C and eight days in the main digestion at 33°C, with and without prepasteurisation. None of the processes inactivated bovine Parvovirus (strain Haden) completely. Even by pasteurisation of the digested sludge this virus could not be inactivated in all cases.

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Martínez, Manuel, María J. Avedillo, José M. Quintana, and José L. Huertas. "COPAS: A New Algorithm for the Partial Input Encoding Problem." VLSI Design 14, no. 2 (January 1, 2002): 171–81. http://dx.doi.org/10.1080/10655140290010088.

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Frequently, the logic designer deals with functions with symbolic input variables. The binary encoding of such symbols should be chosen to optimize the final implementation. Conventionally, this input encoding (IE) problem has been solved in a two-step process. First step generates constraints on the relationship between codes for different symbols, called group constraints. In a following step, symbols are encoded such that constraints are satisfied. This paper addresses the partial input encoding problem (PIE), a variation of the IE problem which generates codes of minimum length. The role of group constraints within the framework of the PIE problem has been questioned. This paper describes an algorithm that unlike conventional approaches, which try to maximize the number of satisfied constraints, targets the economical implementation of each input constraint. The proposed approach is based on a powerful heuristic that produces high quality results in shorter time compared to previous algorithm.

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Dyartanti, Endah Retno, Margono Margono, Anisa Raditya Nurohmah, Shofirul Sholikhatun Nisa, and Novan Riantosa. "Two Step and Direct Fermentation in the Production of Ethanol from Starch: A Short Review." Equilibrium Journal of Chemical Engineering 4, no. 1 (January 19, 2021): 29. http://dx.doi.org/10.20961/equilibrium.v4i1.46130.

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Abstract. Ethanol as a renewable fuel has been widely produced in various countries. One source of raw material for producing ethanol is starch. The process of producing ethanol from starch needs to be pretreated so that starch molecules can split into smaller ones. However, this process requires pre-treatment which will expensive more than ethanol from sugar. There are two types of pretreatment i.e. two-step ethanol production and direct fermentation. There is two kind of hydrolysis, acid hydrolysis, and enzymatic hydrolysis. Two-step ethanol production is a conventional method that separates pretreatment and fermentation process, while direct fermentation is the direct production of starch into ethanol using recombinant yeast that co-produces enzymes such as amylose and glucoamylase. Two-step ethanol production has the advantage of high yield but needs high cost whereas, direct fermentation has the advantage of low-cost production but needs longer time. Common starch to ethanol production consists of two stages, namely hydrolysis of raw materials into glucose and fermentation into ethanol. Both of these processes can be run on average at temperatures of 30-80oC with a pH range of 4-6 and varying time intervals. The enzyme used depends on the source of the starch, but the most commonly used is Saccharomyces cerevisiae.Keywords: Ethanol, starch, pre-treatment

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Antov, Mirjana. "Bioseparations in aqueous two-phase systems." Acta Periodica Technologica, no. 36 (2005): 145–54. http://dx.doi.org/10.2298/apt0536145a.

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Bioseparations conducted in aqueous two-phase systems offer a great number of advantages over the conventional separation techniques. Among them the most relevant are rapid mass transfer due to low interfacial tension, rapid and selective separation, easiness of operation mode, reliability in scale-up biocompatibility and environment-friendly features, and possibility of process integration when applied in biomolecule production. Upon overcoming the major problem - mostly empirical establishment of operating conditions bioseparations in aqueous two-phase systems will become a necessary step in both existing and newly developed bioprocesses for the primary recovery of products.

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Kim and Choi. "Indirect Time-of-Flight Depth Sensor with Two-Step Comparison Scheme for Depth Frame Difference Detection." Sensors 19, no. 17 (August 23, 2019): 3674. http://dx.doi.org/10.3390/s19173674.

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A depth sensor with integrated frame difference detection is proposed. Instead of frame difference detection using light intensity, which is vulnerable to ambient light, the difference in depth between successive frames can be acquired. Because the conventional time-of-flight depth sensor requires two frames of depth-image acquisition with four-phase modulation, it has large power consumption, as well as a large area for external frame memories. Therefore, we propose a simple two-step comparison scheme for generating the depth frame difference in a single frame. With the proposed scheme, only a single frame is needed to obtain the frame difference, with less than half of the power consumption of the conventional depth sensor. Because the frame difference is simply generated by column-parallel circuits, no access of the external frame memory is involved, nor is a digital signal processor. In addition, we used an over-pixel metal–insulator–metal capacitor to store temporary signals for enhancing the area efficiency. A prototype chip was fabricated using a 90 nm backside illumination complementary metal–oxide–semiconductor (CMOS) image sensor process. We measured the depth frame difference in the range of 1–2.5 m. With a 10 MHz modulation frequency, a depth frame difference of >10 cm was successfully detected even for objects with different reflectivity. The maximum relative error from the difference of the reflectivity (white and wooden targets) was <3%.

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Zhu, Rong, Jin Qiang Liu, Jing Tao Wang, Ping Huang, Yan Jun Wu, and Xiang Zhao. "Improvement of Strength of Mg-12Gd-3Y-0.5Zr Alloys Processed by Combination of ECAP and Extrusion." Materials Science Forum 682 (March 2011): 211–16. http://dx.doi.org/10.4028/www.scientific.net/msf.682.211.

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Equal channel angular pressing (ECAP) has been used to refine the grain size of Mg-12Gd-3Y-0.5Zr billet at about 400°C because it lacks sufficient ductility at low temperatures. However, <0001> peak intensity is oriented about 50º from the extrusion direction, which facilitates the basal slip, and decreases the yield strength. We have employed conventional extrusion at 300°C following ECAP to modify the texture in hard orientation. This two-step process makes use of two strengthening mechanisms a) grain boundary strengthening due to small grain size, and (b) texture strengthening due to grains in hard orientation. The samples processed by the two-step show the yield and ultimate strength to 283 and 308 MPa, respectively. Moreover, the activation of <c+a> slip and fine grains resulted from the ECAP helped to maintain a good ductility even after significant straining from conventional extrusion.

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Adapa, Sathish Kumar, Dowluru Sreeramulu, and Jagadish. "Classification and Automatic Feature-Based Extraction Approach for Cylindrical and Milling Parts." International Journal of Manufacturing, Materials, and Mechanical Engineering 11, no. 3 (July 2021): 55–73. http://dx.doi.org/10.4018/ijmmme.2021070104.

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This paper reports classification and automatic extraction of various cylindrical and milling features in conventional machining process parts. In this work, various algorithms like hole recognition algorithm (HRA) and milling feature recognition algorithm (MFRA) have been used for identification of different cylindrical and milling features. A cylindrical feature is identified based on specific logical rules, and milling feature is identified based on the concept of concave decomposition of edges. In-house developed JAVA program is used to write algorithm, and then validation of the algorithm is done through two case studies. The HRA and MFRA algorithms extract the cylindrical features (through holes, blind holes, taper holes, and bosses) and milling features (slot, blind slot, step, blind step, pockets) precisely. The current work is well suitable to extract the features in conventional machining parts and thereby improve the downstream applications likes process planning, CAPP, CAM, etc.

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Choisnard, Luc, David Durand, Dominique Vercaigne-Marko, Naima Nedjar-Arroume, Pascal Dhulster, and Didier Guillochon. "A simple method for the two-step preparation of two pure haemorphins from a total haemoglobin peptic hydrolysate by conventional low-pressure chromatographies." Biotechnology and Applied Biochemistry 34, no. 3 (December 1, 2001): 173. http://dx.doi.org/10.1042/ba20010039.

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Zhang, Chunyue, Tiejun Zhao, and Tingting Li. "A Dirichlet Process Mixture Based Name Origin Clustering and Alignment Model for Transliteration." Advances in Artificial Intelligence 2015 (July 29, 2015): 1–10. http://dx.doi.org/10.1155/2015/927063.

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In machine transliteration, it is common that the transliterated names in the target language come from multiple language origins. A conventional maximum likelihood based single model can not deal with this issue very well and often suffers from overfitting. In this paper, we exploit a coupled Dirichlet process mixture model (cDPMM) to address overfitting and names multiorigin cluster issues simultaneously in the transliteration sequence alignment step over the name pairs. After the alignment step, the cDPMM clusters name pairs into many groups according to their origin information automatically. In the decoding step, in order to use the learned origin information sufficiently, we use a cluster combination method (CCM) to build clustering-specific transliteration models by combining small clusters into large ones based on the perplexities of name language and transliteration model, which makes sure each origin cluster has enough data for training a transliteration model. On the three different Western-Chinese multiorigin names corpora, the cDPMM outperforms two state-of-the-art baseline models in terms of both the top-1 accuracy and mean F-score, and furthermore the CCM significantly improves the cDPMM.

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PENG, CHAO, DESEN ZHAO, GANG HE, MINGZHONG HE, JIANHE HONG, HAIFENG LI, and YANSHENG GONG. "CONVENIENT PREPARATION OF Pb(ZrxTi1-x)O3 THIN FILMS BY A COMBINATORIAL SYNTHESIS PROCESS." Functional Materials Letters 04, no. 03 (September 2011): 231–35. http://dx.doi.org/10.1142/s1793604711002068.

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In order to carry out a convenient preparation of Pb ( Zr x Ti 1-x) O 3 thin films by combinatorial chemical solution deposition process, two kinds of Pb ( Zr x Ti 1-x) O 3 precursor solutions ( PbTiO3 precursor solution and PbZrO3 precursor solution) were prepared by a simple process. There is no distillation and no inert gas shielding in the process, and the precursors are more stable than the conventional precursor solution. A series of Pb ( Zr x Ti 1-x) O 3 samples (x = 0.1–0.9, in step of 0.1 amount change) were prepared using the two precursor solutions. The process was fast and saved time. There were strong exothermic reactions for the samples with the Zr content x in a short range from x = 0.23 to 0.27 at 161–200°C. The Pb ( Zr x Ti 1-x) O 3 thin films showed perovskite structure with strong (111)-preferred orientation. The structure and ferroelectric property of the PZT thin films are comparable with those of the PZT fabricated by conventional process.

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Deng, Yong, Man Xu, Yugao Zhang, Guofu Zhou, Nan Li, and Xiaoqun Qiu. "Non-water dyeing process of reactive dyes in two organic solvents with temperature-dependent miscibility." Textile Research Journal 89, no. 18 (January 2, 2019): 3882–89. http://dx.doi.org/10.1177/0040517518819840.

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In this paper, a non-water dyeing process using two organic solvents with temperature-dependent miscibility was developed. Fixation of three conventional reactive dyes on cotton yarn could reach 97% using one dyeing bath consisting of two solvents. Only one washing step at room temperature was needed to get satisfactory fastness after the fixation process. In particular, the two selected organic solvents could interconvert from immiscible to miscible when the temperature interchanged from 30 to 90℃. This unique physical property makes the separation and recycling processes of organic solvents extremely easy and energy saving. A 1 kg yarn package was dyed using this dyeing process: the color deviation (△E) of the inner and outer yarns was less than 1.0 and the tensile strength decreased by 8.5–18.0%. The results show that this dyeing process is extremely promising.

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Vittayakorn, Wanwilai C., Rattikorn Yimnirun, and Supon Ananta. "Composition, Structure and Properties of PZT-BT Ceramics Prepared by Two-Stage Sintering." Key Engineering Materials 421-422 (December 2009): 436–39. http://dx.doi.org/10.4028/www.scientific.net/kem.421-422.436.

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Ceramic solid solutions within the system (1-x)PZT-xBT, where x = 0.1, 0.2, 0.3, 0.4 and 0.5, were prepared by conventional mixed-oxide method combined with a two-stage sintering procedure. A sintering time of 2 h at 1000 °C followed by a second step in the temperature range of 1000-1200 °C for 2 h was employed to all samples and compared to the one-step sintering process. Phase formation, densification and microstructure of all ceramics were examined via X-ray diffraction (XRD), Archimedes method and scanning electron microscope (SEM). The results lead to the conclusion that the pure perovskite phase and high densification of (1-x)PZT-xBT ceramics with fine grain can be successfully achieved under suitable two-stage sintering conditions.

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Naziris, Nikolaos, Natassa Pippa, and Costas Demetzos. "A Novel, Nontoxic and Scalable Process to Produce Lipidic Vehicles." Materials 13, no. 21 (November 8, 2020): 5035. http://dx.doi.org/10.3390/ma13215035.

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Lipidic vehicles are novel industrial products, utilized as components for pharmaceutical, cosmeceutical and nutraceutical formulations. The present study concerns a newly invented method to produce lipidic vehicles in the nanoscale that is simple, nontoxic, versatile, time-efficient, low-cost and easy to scale up. The process is a modification of the heating method (MHM) and comprises (i) providing a mixture of an amphiphilic lipid and a charged lipid and/or a fluidity regulator in a liquid medium composed of water and a liquid polyol, (ii) stirring and heating the mixture in two heating steps, wherein the temperature of the second step is higher than the temperature of the first step and (iii) allowing the mixture to cool down to room temperature. The process leads to the self-assembly of nanoparticles of small size and good homogeneity, compared with conventional approaches that require additional size reduction steps. In addition, the incorporation of bioactive molecules, such as drugs, inside the nanoparticles is possible, while lyophilization of the products provides long-term stability. Most importantly, the absence of toxic solvents and the simplicity guarantee the safety and scalability of the process, distinguishing it from most prior art processes to produce lipidic vehicles.

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Journal articles on the topic 'Conventional two-step process'

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