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Yuan, Xiaoling, Yi Guo, Can Cui, and Hao Cao. "Time-of-Use Pricing Strategy of Integrated Energy System Based on Game Theory." Processes 10, no. 10 (October 8, 2022): 2033. http://dx.doi.org/10.3390/pr10102033.
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The integrated energy system is the mainstream energy utilization form of integrating a power system, natural gas system and thermal system, which provides a new way to solve the problem of renewable energy accommodation. The integrated energy system includes a variety of energy generation and conversion equipment, and its internal electricity, gas, cooling and thermal systems must balance the multiple energy supplies required by users. The integrated energy supplier (IES) and integrated energy user (IEU), as different stakeholders, pursue the maximization of their own profit. However, integrated energy suppliers should consider their market share and the sustainability of participating in market competition. Based on the constraints of energy access, conversion and accommodation, and the equipment for energy generation, conversion and consumption, we established an energy flow model. Constrained by the dynamic equilibrium of the supply of integrated energy suppliers and the demand of integrated energy users, a Stackelberg game model of integrated energy suppliers and users was established, and the existence of a Nash equilibrium solution of the game was proved. A genetic algorithm was used to solve the Nash equilibrium solution under two conditions aiming at the integrated energy supplier’s maximum profit and target profit. Considering the demand of integrated energy users in different time periods, we analyzed the time-of-use pricing strategy of the integrated energy based on the balance of the energy supply and demand. The results of a case study show that if integrated energy suppliers adopt the time-of-use pricing strategy of maximum profit, the energy load distribution of integrated energy users can be smoothed, and energy utilization and economic benefits of the system can be improved. If integrated energy suppliers adopt the time-of-use pricing strategy of target profit, enlarge the market by limiting their own profit and obtain the purchase willingness of integrated energy users by reducing the energy price, they can have a larger market share, a more reliable profit and a guarantee of long-term participation in market transactions.
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Sivaraman, Krishnan, and Dileep Kulkarni. "Welding of Stainless Steel - A Heavy Engineering Perspective." Advanced Materials Research 794 (September 2013): 380–90. http://dx.doi.org/10.4028/www.scientific.net/amr.794.380.
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Stainless steels are engineering materials capable of meeting a wide range of design criteria. They exhibit excellent corrosion resistance, strength at elevated temperature, toughness at cryogenic temperature and fabrication characteristics, and they are selected for a broad range of consumer, commercial, and industrial applications. In the fabrication of stainless steel products, components, or equipment, manufacturers employ welding as the principal joining method. Stainless steels possess good weldability and a welded joint can provide optimum corrosion resistance, strength, and fabrication economy provided reasonable care is exercised during welding. L&T's Heavy Engineering (HE) has established a reputation for quality products in the global market with its strong engineering capabilities and state-of-the-art manufacturing facilities. It manufactures and supplies various critical equipments like reactors, vessels, heat exchangers and inter-connecting piping to Fertilizer, Refinery, Petrochemical, Chemical, Oil & Gas, Power, Nuclear and allied Strategic sectors. The wide spectrum of equipments mentioned involves fabrication of various grades of Stainless Steel (SS)like Austenitic, Ferritic, Martensitic, Duplex, Super Duplex etc. This paper discusses some of the high productivity welding processes and the techniques being used in manufacturing Stainless Steel vessels at Larsen & Toubro’s Heavy Engineering such as: Narrow groove welding of high thickness SS joints by Submerged Arc Welding(SAW), High deposition SS weld surfacing using Electro Slag Strip Cladding (ESSC), Hotwire GTAW for joining & surfacing of SS, SS Liner welding by GTAW for critical Urea Service applications, Automatic Tube to Tube sheet Welding etc.
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Carr, Stephen H. "Up Close: Northwestern University Materials Research Center." MRS Bulletin 11, no. 5 (October 1986): 36. http://dx.doi.org/10.1557/s088376940005449x.
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The Materials Research Center at Northwestern University is an interdisciplinary center that supports theoretical and applied research on experimental advanced materials. Conceived during the post-Sputnik era, it is now in its 26th year.The Center, housed in the university's Technological Institute, was one of the first three centers funded at selected universities by the federal government in 1960. The federal government, through the National Science Foundation, now supplies $2.4 million annually toward the Center's budget, and Northwestern University supplements this amount. Approximately one third of the money is used for a central pool of essential equipment, and the other two thirds is granted to professors for direct support of their research. Large amounts of time on supercomputers are also awarded to the Materials Research Center from the National Science Foundation and other sources.The Center's role enables it to provide partial support for Northwestern University faculty working at the frontiers of materials research and to purchase expensive, sophisticated equipment. All members of the Center are Northwestern University investigators in the departments of materials science and engineering, chemical engineering, electrical engineering, chemistry, or physics. The Materials Research Center is a major agent in fostering cross-departmental research efforts, thereby assuring that materials research at Northwestern University includes carefully chosen groups of faculty in physics, chemistry, and various engineering departments.
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GONCHAROV, ANTON A. "CRITICAL ASSESSMENT OF THE IMPLEMENTATION OF TARGET PROGRAMS IN SOLVING THE PROBLEM OF TECHNICAL RE-EQUIPMENT OF AGRICULTURE." Agricultural engineering, no. 4 (2021): 53–58. http://dx.doi.org/10.26897/2687-1149-2021-4-53-58.
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Over the years of results-based management, the agricultural sector of Russia has enhanced a signifi cant increase in production volumes. Special results have been achieved in crop production, primarily in the production of grain crops. This was urgent in terms of meeting the needs of the domestic market and increasing the volume of supplies to foreign markets. Despite a number of positive results achieved in agriculture through the implementation of targeted programs, especially during the period of counter-Russian sanctions and the ongoing policy of import substitution, the problem of providing the industry with means of production has not been fully solved. This hinders the implementation of Russia’s export capacity. To further increase the volume of agricultural production, the technical re-equipment of the industry is required, which will increase the effi ciency of production. To this end, it is necessary to critically evaluate the implementation of targeted programs used to solve the problem of technical re-equipment. This indicates the relevance of the research topic. The study was conducted on the basis of a systematic approach (monographic, economic and statistical methods, the method of deduction) with the use of relevant materials of offi cial statistics. During the implementation of targeted programs, the pace of technical re-equipment of agriculture was extremely low, accompanied by a considerable share of obsolete imported agricultural machinery, tractors and combine harvesters, and decresing energy supply of the industry. Insuffi cient provision of agriculture with means of production constrains the growth rate of labor productivity. The targets set in the State Program for the renewal of agricultural machinery are low and have been exceeded for several previous years, and they do not indicate a high rate of technical re-equipment of agriculture. The study results serve as a basis for adjusting the current mechanism of results-based management of agricultural development.
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Santos, Fernanda Ribeiro dos, Idalmo Montenegro de Oliveira, Luiz Carlos Santos, Rafaela Esteves Godinho Leal, and Marcelo Cardoso. "Pedagogical strategies for Chemical Engineering courses: Skills development through Project-based learning (PBL)." Research, Society and Development 10, no. 7 (June 26, 2021): e40310715545. http://dx.doi.org/10.33448/rsd-v10i7.15545.
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The formal curriculum practices in engineering education have been rethought in order to meet the growing demand for the development of the more traditional skills, as well as newer multidisciplinary skills for the students, making them protagonists in their own development and forging the curriculum through concrete activities (curriculum in action) that go beyond the prescribed curriculum. As a fundamental part of this process, a project was developed by students and professors of the Chemical Engineering course, where the Project-Based Learning methodology was applied. During the traditional curriculum course "Operations and Processes Laboratory", students were able to work with the curriculum in action through four main activities that required the application of technical knowledge linked to communication skills and problem solving, adaptation to reality, proactivity and analytical ability. The development of competences and skills by the students was analyzed based on the reports they presented as a result of their group projects and summarized in a matrix of general engineering competences, based on the Brazilian National Curriculum Guidelines. Through this matrix it was possible to conclude that the students solved the real problem situations using the technical knowledge learned at the University, while taking into account the relevant economic, environmental and social aspects. They defined the theme of their work, goals and the methodology to be developed with complete autonomy. They exercised creativity and used multidisciplinary skills to seek solutions and adapt resources, acquiring equipment and supplies, developing and building adaptively, while utilizing the tools at their disposal. They exercised the analytical capacity to elucidate the results and present improvements and also introduced digital technologies to facilitate communication and other processes.
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Kareem, Akeem Bayo, and Jang-Wook Hur. "A Feature Engineering-Assisted CM Technology for SMPS Output Aluminium Electrolytic Capacitors (AEC) Considering D-ESR-Q-Z Parameters." Processes 10, no. 6 (May 30, 2022): 1091. http://dx.doi.org/10.3390/pr10061091.
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Recent research has seen an interest in the condition monitoring (CM) approach for aluminium electrolytic capacitors (AEC), which are present in switched-mode power supplies and other power electronics equipment. From various literature reviews conducted and from a failure mode effect analysis (FMEA) standpoint, the most critical and prone to fault component with the highest percentage is mostly capacitors. Due to its long-lasting ability (endurance), CM offers a better paradigm for AEC due to its application. However, owing to severe conditions (over-voltage, mechanical stress, high temperature) that could occur during use, they (capacitors) could be exposed to early breakdown and overall shutdown of the SMPS. This study considered accelerated life testing (electrical stress and long-term frequency testing) for the component due to its endurance in thousands of hours. We have set up the experiment test bench to monitor the critical electrical parameters: dissipation factor (D), equivalent series resistance (ESR), quality factor (Q), and impedance (Z), which would serve as a health indicator (HI) for the evaluation of the AECs. Time-domain features were extracted from the measured data, and the best features were selected using the correlation-based technique.
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Jaffar, Azhar, Norashikin M. Thamrin, Megat Syahirul Amin Megat Ali, Mohamad Farid Misnan, Ahmad Ihsan Mohd Yassin, and Noorolpadzilah Mohamed Zan. "Spatial interpolation method comparison for physico-chemical parameters of river water in Klang River using MATLAB." Bulletin of Electrical Engineering and Informatics 11, no. 4 (August 1, 2022): 2368–77. http://dx.doi.org/10.11591/eei.v11i4.3615.
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Water quality is one of the most highly debated issues worldwide at the moment. Inadequate water supplies affect human health, hinder food production, and degrade the environment. Using contemporary technology to analyze pollution statistics can help solve pollution issues. One option is to take advantage of advancements in intelligent data processing to conduct hydrological parameter analysis. To perform conclusive water quality studies, a lot of data is necessary. Unfilled data (information gaps) in the long-term hydrological data set may be due to equipment faults, collection schedule delays, or the data collection officer’s absence. The lack of hydrological data skews its interpretation. Therefore, interpolation is used to recreate and fill missing hydrological data. From 2012 to 2017, the Klang River’s biochemical oxygen demand (BOD) in Selangor, Malaysia, was sampled. This study examined three methods of interpolation for their effectiveness using the MATLAB software: piecewise cubic hermite interpolating polynomial (PCHIP), cubic Spline data interpolation (Spline), and modified Akima partitioned cubic hermite interpolation (Makima). The accuracy is assessed using root mean square error (RMSE). All interpolation algorithms offer excellent results with low RMSE. However, PCHIP delivers the best match between interpolated and original data.
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Dadhich, Amit, Sanjay Arya, and Arti Kapil. "Exploring the Pathogens Present at the Patient Care Equipments & Supplies to Sensitise the Health Care Workers for Preventing Health Care-Associated Infections among In-Patients." Nursing Journal of India CV, no. 06 (2022): 283–86. http://dx.doi.org/10.48029/nji.2014.cv608.
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Health care-associated infection (HCAI) is an infection that a person acquires in hospital after 24 hours of his/her admission. A health care worker (HCW) does not have any right to provide another infection to in-patients. While caring the patients, HCW innocently or otherwise can transmit various pathogens to the patient. It is both ethically and legally wrong and HCW is answerable for it. The current study was conducted with the objectives to find out the rate of presence of pathogens at the patient care equipments & supplies, to identify the most common pathogens present at the patient care equipments & supplies and to identify such equipments & supplies that are at high risk of contamination. Investigator collected 1,145 samples of different equipments & supplies used for patient care from operation theaters, labour room & medical wards of a tertiary care hospital in New Delhi. The sample was collected from April 2012 to April 2013 by random sampling. Out of 1,145 samples, 112 were positive or contaminated with certain kind of pathogen. The finding revealed that the contamination rate of patient care equipments & supplies is 9.78 percent. The most common and frequent pathogen present at the equipments & supplies is Pseudomonas (39.29%) and water of oxygen humidifier is most commonly and frequently infected (47.32%). Nurses as the backbone of hospital should strictly adhere to the policies and protocols of the institution. She/he must update the knowledge of infection control practices and various methods of controlling HCAI including hand hygiene, disinfection of patient care equipments & supplies and cleanliness of environment. A Nurse should also transmit this knowledge to other team members so as to minimise the health care-associated infection rate.
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Mursalin, Mursalin. "Engineering Process Of Deodorization To Improve Product Quality Of Red Palm Oil With Rich Of Carotene." Indonesian Food Science and Technology Journal 1, no. 1 (May 18, 2018): 20–26. http://dx.doi.org/10.22437/ifstj.v1i1.5014.
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Efforts to develop the production technology of high quality red palm-oil (RPO) in order to provide source of food ingredient that naturally rich of nutrients, become urgents regarding the need of such products drastically increased recently. Application of deodorization technology by temperature, time, and deodorizer pressure combinations (engineering of deodorization process) are studied and evaluated to obtain good quality of RPO. Crude palm oil (CPO) used in this research were supplied by PT. Salim Ivomas (Bimoli) Jakarta. The equipments used were degumming and neutralization unit, deodorization unit and other equipment units to analize the oil physico-chemical properties. The research consisted of 5 stages as the following: characterising CPO physico-chemical properties, conducting chemically degumming and deacidification, process enginering of deodorization, characterizing of physico-chemical properties and organoleptic of RPO resulted, and analyzing data for product resulted from process engineering applied. Deodorization with the range of temperature and process duration of 135–145 oC (408–418 K) and 1–4 hours have led to carotene retention decreasing (%) following the equation “Carotene Retention (%) = -764 x ln(absolute temperature) + 4693” and process duration with the equation “Carotene Retention (%) = -7.81 x ln(process duration) + 91.02”; and also resulted odor intensity with the equation “Odor Intensity = 0.08 x (squared absolute temperature) – 66.88 x (absolute temperature) + 13823” and duration process with the equation “Odor Intensity = 0.315 x (squared process duration) – 1.52 x (process duration) + 5.268”. Effective deodorization to produce RPO with the content of free fatty acid and peroxide value that met the requirements of Indonesian National Standard (SNI) quality of carotene content above 400 ppm and odor scale below 3.3, were the combination of temperature (T) of 141.34 oC, heat process duration (t) of 2.35 hours and vacuum pressure of (P) of 20 mmHg. The resulted RPO contained free fatty acid and peroxide value of 0.11% dan 0.12 meq/kg oil respectively, total carotene of 444.09 ppm and odor value of 3.21
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SRETENOVIC, IVAN. "New learnings and strategies for meeting future recovery boiler particulate emission limits with existing electrostatic precipitators." June 2021 20, no. 6 (July 1, 2021): 405–12. http://dx.doi.org/10.32964/tj20.6.405.
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It is foreseeable that recovery boiler particulate emission limits in the United States and Canada will continue to get more stringent with time. Because of this, continued improvement of emission control equipment, as well as a better understanding of how operating parameters affect performance, are necessary. Although electrostatic precipitators (ESPs) are often viewed as a mature technology, many improvements in ESP technology continue to be developed. In recent years, academic efforts have improved the understanding of recovery boiler operating conditions on ESP performance. Additionally, advancements in materials, power supplies, and design continue to improve the efficiency and reliability of ESPs. This paper discusses how recovery boiler and electrostatic precipitator (ESP) operating factors affect ESP performance based on process simulations and practical experience, and how these learnings can be implemented to improve future operation of existing ESPs.
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EROKHIN, MIKHAIL N., ALEKSEI S. DOROKHOV, VLADIMIR V. KIRSANOV, and EKATERINA L. CHEPURINA. "CONCEPTUAL GROUNDS FOR THE CONSTRUCTION OF A REGIONAL MULTIFUNCTIONAL SERVICE CENTER FOR DAIRY LIVESTOCK." Agricultural engineering, no. 1 (2021): 4–10. http://dx.doi.org/10.26897/2687-1149-2021-1-4-10.
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Abstract. The paper outlines the main problems related to the technical service of machines and equipment used in dairy farming. The authors analyze the companies that provide their services to dairy farms of various sizes and forms of ownership, ranging from personal subsidiary farms to agricultural holdings. The main disadvantages of technical service of small and medium farms are shown, namely: large number and disunity of individual equipment suppliers; lack of incoming control of products and materials being in contact with milk; inconsistency in a number of cases of the proposed technical and technological solutions and equipment operation modes with the international requirements and other regulatory documents; impossibility of providing qualifi ed consulting, technical, fi nancial, legal and economic support to agricultural producers. The authors propose a structural and logistic model of a regional multifunctional service center for the livestock breeding industry, providing comprehensive technological, technical and operational services related to consulting, training, choosing the best available technologies and appropriate sets of machines. The multifunctional service center is expected to unite the disparate eff orts of regional service companies and dealers, improve the quality of services provided to commodity producers, and raise the level of production on small and medium-size farms.
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Wang, Chia-Nan, Chien-Chang Chou, Thanh-Tuan Dang, Hoang-Phu Nguyen, and Ngoc-Ai-Thy Nguyen. "Integrating Triple Bottom Line in Sustainable Chemical Supplier Selection: A Compromise Decision-Making-Based Spherical Fuzzy Approach." Processes 10, no. 5 (April 30, 2022): 889. http://dx.doi.org/10.3390/pr10050889.
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As a consequence of increased awareness of environmental preservation and the associated rigorous regulations, the adoption of sustainable practices has become a crucial element for corporate organizations in regard to their supply chains. In the chemical industry, which is characterized by high risks, high pollution, and high efficiency, these characteristics can help businesses analyze their long-term development and sustainability. The goal of this research is to analyze and choose possible suppliers based on their sustainability performance in the chemical sector. A methodology based on multi-criteria decision making (MCDM) is proposed for this evaluation, using spherical fuzzy analytical hierarchy process (SF-AHP) and combined compromise solution (CoCoSo) methods, in which the novel spherical fuzzy sets theory is employed to present the ambiguous linguistic preferences of experts. In the first stage, an evaluation criteria system is identified through literature review and experts’ opinions. The SF-AHP is used to determine the criteria weights, while the CoCoSo method is utilized to select the right sustainable supplier. A case study in the chemical industry in Vietnam is presented to demonstrate the effectiveness of the proposed approach. From the SF-AHP findings, “equipment system and technology capability”, “flexibility and reliability”, “logistics cost”, “green materials and technologies”, and “on-time delivery” were ranked as the five most important criteria. From the CoCoSo analysis, Vietnam National Chemical Group (CHE-05) was found to be the best supplier. A sensitivity study and a comparison analysis of methods were also conducted to verify the robustness of the proposed model, and the priority rankings of the best suppliers were very similar. To the best of our knowledge, this is the first study that has proposed SF-AHP and CoCoSo to prioritize SSS evaluation criteria and determine the best alternatives. The suggested method and findings can be used to make well-informed decisions that help businesses to achieve supply chain sustainability, capture opportunities, and maintain competitiveness through reconfiguring resources. The method could be useful for case studies in other countries and for other sustainability problems.
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GASPARYAN, IRINA N. "PROBLEMS RELATED TO THE PRODUCTION OF HUMIC FERTILIZERS AND THEIR SOLUTIONS." Agricultural engineering, no. 1 (2022): 23–27. http://dx.doi.org/10.26897/2687-1149-2022-1-23-27.
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Further development of organic agricultural production requires large volumes of organic fertilizers. Due to the sharp reduction in cattle, there is a lack of organic fertilizer in the form of animal waste. To solve this problem, eleven technological lines for processing natural organic raw materials in the form of peat, brown coal, and sapropel were developed, considering customers’ technical requirements, and then delivered to some regions of Russia and Belarus. The authors analyzed the operation of these lines, and based on the study of the operation of individual units and assemblies, identified technical and technological problems. They studied and analyzed the possibilities of developing technological lines using modular equipment of machine-building organizations to process organic raw materials for making humic fertilizers. The research results made it possible to modernize individual technological lines using new innovative developments and modular equipment. Using a new design of a hydromechanical cleaner to clean the peat suspension before feeding it into the reactor increased the level of its purification to 97…98%. Reinforcement of the technological line with modular equipment (vibratory mill of MV-20 type) for grinding coal increased the quality of the reactor and reduced the ballast content after filtration to 1…3%. The dispersion of the fertilizer suspension supplied for filtration decreased to 50…70 microns. The introduction of the design of a new high-power dismembrator made it possible to reduce the production cycle time by 30 minutes. An additional installation of a hydromechanical cavitator increased the efficiency of extracting humic acids from organic raw materials. The microelement dosing system has been modernized to produce concentrated fertilizers up to 2.5 tons per shift. The research results have determined the expediency of further development of technological lines based on modular equipment.
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Wojdalski, Janusz, Bogdan Dróżdż, Janusz Piechocki, Marek Gaworski, Zygmunt Zander, and Jan Marjanowski. "Determinants of water consumption in the dairy industry." Polish Journal of Chemical Technology 15, no. 2 (July 1, 2013): 61–72. http://dx.doi.org/10.2478/pjct-2013-0025.
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This paper analyzes the correlations between selected technical, process and production factors, equipment profiles and water consumption statistics in four types of dairy plants. Dairy plants were surveyed both individually and in groups. Water consumption was most highly correlated (r > 0.868) with equipment profiles. The highest water consumption was observed in dairy plants operating milk powder departments. In those plants, organization and production factors could significantly reduce water consumption levels because in addition to milk powder, those plants also supplied eight other products. The indicators of water consumption per unit of the final product were correlated (at 0.820 > | r | > 0.663) with equipment profiles, the degree of process automation and employment. Variations in water consumption per unit of the final product were best explained in small plants supplying several products. The presented equations can be used to optimize water demand of various types of equipment and to determine the correlations with energy consumption for wastewater treatment. Our results can contribute to the development of water consumption models in dairy plants and the implementation of clean production standards.
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Ornelas, Fernando, Alejandro Santiago, Salvador Ibarra Martínez, Mirna Patricia Ponce-Flores, Jesús David Terán-Villanueva, Fausto Balderas, José Antonio Castán Rocha, Alejandro H. García, Julio Laria-Menchaca, and Mayra Guadalupe Treviño-Berrones. "The Internet Shopping Optimization Problem with Multiple Item Units (ISHOP-U): Formulation, Instances, NP-Completeness, and Evolutionary Optimization." Mathematics 10, no. 14 (July 19, 2022): 2513. http://dx.doi.org/10.3390/math10142513.
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In this work, we investigate the variant of the Internet Shopping Optimization Problem (ISHOP) that considers different item units. This variant is more challenging than the original problem. The original ISHOP is already known as a combinatorial NP-hard problem. In this work, we present a formal proof that the ISHOP variant considering different item units belongs to the NP-Hard complexity class. The abovementioned variant is familiar to companies and consumers who need to purchase more than one unit of a specific product to satisfy their requirements. For example, companies buy different quantities of construction materials, medical equipment, office supplies, or chemical components. We propose two new evolutionary operators (crossover and mutation) and an unfeasible solution repair method for the studied ISHOP variant. Furthermore, we produce a new benchmark of 15 synthetic instances where item prices follow a random uniform distribution. Finally, to assess our evolutionary operators, we implemented two Evolutionary Algorithms, a Genetic Algorithm (GA) and a Cellular Genetic Algorithm (CGA), and an experimental evaluation against a Water Cycle Algorithm (WCA) from the state-of-the-art. Experimental results show that our proposed GA performs well with statistical significance.
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Snyder, Merle R. "Testing-Equipment Suppliers Are Out in Force at Plastics Encounter at ANTEC™ 2007." Plastics Engineering 63, no. 7 (July 2007): 50–53. http://dx.doi.org/10.1002/j.1941-9635.2007.tb00153.x.
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Düthorn, Berthold. "Assessment of Cleanroom Suitability of Equipment and Materials by Chemical Concentration—ISO Standard Now Available for Designers, Suppliers, and Users." Journal of the IEST 61, no. 1 (December 1, 2018): 55–59. http://dx.doi.org/10.17764/1098-4321.61.1.55.
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Schorr, Michael, Benjamín Valdez, Amir Eliezer, Ricardo Salinas, and Carlos Lora. "Managing corrosion in desalination plants." Corrosion Reviews 37, no. 2 (March 26, 2019): 103–13. http://dx.doi.org/10.1515/corrrev-2018-0038.
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AbstractEnvironment quality, clean energy and worldwide water scarcity have been established today as central disciplines in modern science, engineering and technology. The innovative desalination technology of saline water (SW) contributes to alleviate these problems by producing fresh water from SW, mainly seawater and brackish water. Desalination plants (DPs) have a high level of corrosion risk as they handle and process aggressive SW under severe operating conditions, which include filtration, heat exchange, distillation, evaporation, agitation and circulation and high flow velocities, often turbulent. These SW, that is, sea, brackish and brines, cause localized corrosion such as pitting, crevice, galvanic and stress corrosion. In addition, biological fouling and mineral scaling are frequent nuisances that alter the equipment surface performance and induce corrosion. Two main technologies are used to obtain potable water and a brine for disposal: thermal evaporation and membrane separation, called reverse osmosis. The main way to minimize corrosion is the correct selection of corrosion-resistant materials for the fabrication of DP equipment, structures, installations and machinery. To protect the DP materials, industrial paints, polymeric coatings and rubber linings compatible with the DP fluids are applied. Cathodic protection with sacrificial anodic metals and/or impressed direct electrical current and corrosion inhibitors are supplied.
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Mattsson, Ann, Glen Nivert, and Mari Heinonen. "Direct precipitation on demand at large Scandinavian WWTPs reduces the effluent phosphorus load." Water Science and Technology 65, no. 12 (June 1, 2012): 2106–11. http://dx.doi.org/10.2166/wst.2012.126.
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On demand use of direct precipitation of wastewater has been successfully implemented at several large Scandinavian wastewater treatment plants (WWTPs) as a cost-efficient method of treating wastewater bypassing secondary treatment. During wet weather situations or when the capacity of secondary treatment is reduced excess wastewater can be treated through efficient direct precipitation. This increases the total capacity of the WWTP to remove phosphorus during these periods. This treatment strategy allows the WWTPs to meet stringent effluent phosphorus limits without extending secondary treatment of the main plant, despite high wet weather flows. The gain in terms of reduced phosphorus emissions varies depending on local conditions such as climate, collection system and secondary treatment capacity. It also varies from year to year depending on the weather and reductions of capacity due to planned refurbishing or unplanned breakdown of equipment. Operating chemical precipitation on demand has proved to contain challenges to operation and organisation of the WWTP. These challenges include logistics of start-up, training of staff and maintaining the system between occasions of operation. Sufficient up-stream storage capacity, reliable weather forecasts and good contracts with suppliers of chemicals are keys of success.
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LAMA, ILICH, and DEREK SAIN. "A case study review of wood ash land application programs in North America." February 2021 20, no. 2 (March 1, 2021): 111–20. http://dx.doi.org/10.32964/tj20.2.111.
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Several regulatory agencies and universities have published guidelines addressing the use of wood ash as liming material for agricultural land and as a soil amendment and fertilizer. This paper summarizes the experiences collected from several forest products facility-sponsored agricultural application programs across North America. These case studies are characterized in terms of the quality of the wood ash involved in the agricultural application, approval requirements, recommended management practices, agricultural benefits of wood ash, and challenges confronted by ash generators and farmers during storage, handling, and land application of wood ash. Reported benefits associated with land-applying wood ash include increasing the pH of acidic soils, improving soil quality, and increasing crop yields. Farmers apply wood ash on their land because in addition to its liming value, it has been shown to effectively fertilize the soil while maintaining soil pH at a level that is optimal for plant growth. Given the content of calcium, potassium, and magnesium that wood ash supplies to the soil, wood ash also improves soil tilth. Wood ash has also proven to be a cost-effective alternative to agricultural lime, especially in rural areas where access to commercial agricultural lime is limited. Some of the challenges identified in the review of case studies include lengthy application approvals in some jurisdictions; weather-related issues associated with delivery, storage, and application of wood ash; maintaining consistent ash quality; inaccurate assessment of required ash testing; potential increased equipment maintenance; and misconceptions on the part of some farmers and government agencies regarding the effect and efficacy of wood ash on soil quality and crop productivity.
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KATAEV, YURIY V. "STUDY OF CHANGE TRENDS IN THE MARKET FOR REUSED AGRICULTURAL MACHINERY IN THE AGRICULTURAL SECTOR OF RUSSIA." Agricultural engineering, no. 4 (2021): 21–27. http://dx.doi.org/10.26897/2687-1149-2021-4-21-27.
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The paper deals with the development of a system of criteria and indicators for the formation and development of the market for reused agricultural machinery (MRUAM) in order to optimize the structure and use of the machine and tractor fl eet. It is noted that the machine and tractor fl eet used in Russian agricultural sector is 35…40% undersupplied with the most demanded agricultural machinery. About 60% of regional farms are focused on purchasing equipment on the reused machinery market based on its technical readiness and cost not exceeding 60…65% of the cost of the new products. The modern concept describing the development of the domestic market for agricultural machinery and the methodology for the MRUAM formation are presented. The authors list the main tasks for the MRUAM formation and present the information and functional structure of MRUAM. Over 3-4 years to come, systemic development of MRUAM in the agricultural sector of Russia will raise the level of technical readiness of agricultural machines by 5…7% and increase the agricultural machinery and tractor fl eet by 50…55 thousand tractors, 10…12 thousand grain harvesters and 3…3.5 thousand forage harvesters. The MRUAM formation in the agricultural sector of Russia, in addition to increasing the size of the machine and tractor fl eet, will signifi cantly strengthen the engineering and technical system of the agricultural sector. Agricultural producers will get the opportunity to simplify the procedure for fi nding prospective suppliers and consumers of agricultural machinery, as well as to formulate real prices for used resources and provide guarantees for completing transactions to the MRUAM participants.
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Yamaguchi, Hitomi, Takeo Shinmura, and Ryota Ikeda. "Study of Internal Finishing of Austenitic Stainless Steel Capillary Tubes by Magnetic Abrasive Finishing." Journal of Manufacturing Science and Engineering 129, no. 5 (December 4, 2006): 885–92. http://dx.doi.org/10.1115/1.2738957.
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This paper studies the internal finishing of capillary tubes using a magnetic abrasive finishing process. Such tubes are used with nanoscale technologies and meet the demands of the present age in medical and chemical equipment. The finishing characteristics are influenced by the magnetic abrasive behavior against the inner surface of the capillary, which is controlled by the supplied amount of magnetic abrasive and the magnetic force acting on it. The development of the finishing unit identifies the characteristics of the magnetic field, which controls the magnetic force, required for the necessary magnetic abrasive behavior. Finishing experiments using SUS304 austenitic stainless steel capillary tube with 800μm inner diameter demonstrate the effects of the supplied amount of the magnetic abrasive on the finishing characteristics, and the results suggest a standard method to determine the amount to achieve sufficient finishing. The run-out of the capillary while rotating at high speed under the cantilever tube support method causes instability of the magnetic abrasive behavior. The effects on the finishing characteristics are discussed, and a method to diminish the run-out is applied. Accordingly, this paper presents the conditions required for the internal finishing of capillary tubes and proposes methods to realize them. The internal finishing of 400μm inner diameter capillary tubes conveys an understanding of the mechanisms involved and demonstrates the usefulness of the proposed methods.
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Tomchuk, Nataliya N., Ekaterina A. Filatova, Daria S. Burakova, Mariam R. Karimova, Nikolay Yu Tretyakov, and Mikhail Yu Bondar. "Laboratory studies of physico-chemical methods to break emulsions stabilized with surfactant-polymer cocktails." PROneft’. Proffessional’no o nefti 6, no. 4 (December 24, 2021): 154–59. http://dx.doi.org/10.51890/2587-7399-2021-6-4-154-159.
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Introduction. Oil field treatment often makes it necessary to combine different methods of well production treatment, taking into account the development regimes and parameters, produced and injected fluids, technical equipment and economic feasibility. The carried-out complex of laboratory tests is aimed at the creation and subsequent destruction of model systems with specified parameters. The list of the considered methods and the temperature regime of the tests are due to the physicochemical parameters and the field specifics. The purpose of this article is to search for an effective method for the primary treatment of well production after SP-flooding — a highly stable oil-water emulsion, additionally stabilized during pumping by means of an ESP.
Materials and methods. The laboratory tests helped to develop an optimal mode of creating an artificial emulsion based on oil from BS10-1 reservoir of the Kholmogorsk field in the Yamalo-Nenets Autonomous Okrug, and a surfactant-polymer cocktail, which simulates well production after SP-flooding. The research tested physicochemical methods of destroying oil-water emulsions, such as their dilution with formation fluids, thermal settling, gravitational separation by centrifugation at RPM = 4000–12000 rpm, introduction of demulsifiers, as well as a combined effect, including all of the above approaches. The tested methods were supplied with the calculated values of the oil phase final water-cut, which allowed us to evaluate the effectiveness of the applied approaches to the destruction of model systems.
Results. It has been found that not all of the applied approaches provide the extraction of the estimated amount of oil from emulsion systems with varying degrees of dilution by formation fluids. Satisfactory destruction of the emulsion was achieved after 10–20 min of centrifugation at T = 40 °C and RPM within 4000–8000 rpm. The traditional introduction of industrial demulsifiers into the studied systems without additional influences is ineffective.
Conclusion. The optimal level of water cut in the oil phase of ≤5% was achieved after diluting the emulsion with formation fluids, with a combined approach to the destruction of the original and diluted emulsion with formation fluids. In addition, the research showed that it is possible to re-use the extracted SP-composition when controlling its physicochemical parameters, taking into account the effect of the introduced additives.
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Binchiciu, Emilia Florina, Nicușor Alin Sîrbu, Daniela Iovănaș, Horia Binchiciu, and Romulus Pascu. "Researh on the Developments of HFIC Allied Powders." Advanced Materials Research 1153 (May 2019): 103–7. http://dx.doi.org/10.4028/www.scientific.net/amr.1153.103.
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The following paper presents the constructive manufacturing solution for low and medium allied powders in continuous flux, by melting in the caster, using high frequency induction currents - HFIC, wires, base material, and continuously discarding the melt over a rotating drum, cooled at a determined speed, thus by optimizing the movement and cooling parameters we can obtain the proper grain size.The functional model has the capability to achieve alloyed powders within a broad range of grain size, recommended in research. The melting furnace can be supplied with solid wires or tubular wires, with a fill coefficient of up to 0.55%, which allows the composite core to be integrated into the alloying system. Also, due to its high degree of flexibility, the equipment allows the HFIC melting crucible to be supplied with more than two wires at a time, a feature that ensures a high level of alloying of the powders to be achieved.The functional model developed in order to manufacture powders continuously was used to produce alloyed powders, insensible to elements burns when alloyed, by passing them, at welding, through the electric arc. Forwards we present physical-chemical characteristics of two powders destined to develop composite core from tubular wire alloyed with chromium and nickel.Repairing hot molds by the MIG molds made of low alloyed improvement steel requires type Fe-2.5% Cr-4.5W-V materials, with high homogeneity of the composite mixture from the making of powdered core of tubular wires.Repairing the semi-mechanized rotors made of martensitic steels from hydropower plants requires tubular (cored) wires that deposit type Fe-12% Cr-4% Ni alloys, possibly even Mo.
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Tanaka, Tomohiro, Tomonori Kato, Tatsuki Otsubo, Atsuhiro Koyama, and Takanori Yazawa. "Control of Spindle Position and Stiffness of Aerostatic-Bearing-Type Air Turbine Spindle." International Journal of Automation Technology 16, no. 4 (July 5, 2022): 456–63. http://dx.doi.org/10.20965/ijat.2022.p0456.
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Air turbine spindles with aerostatic bearings are widely used in ultraprecision machining equipment. Ultraprecision grinding processes using air turbine spindles with aerostatic bearings include constant-pressure dry lapping of nano-polycrystalline diamond (NPD) tools and ultraviolet irradiation polishing of chemical vapor deposition diamond films. In the dry lapping of NPD tools, it is necessary to achieve constant-pressure grinding while flexibly adjusting the contact force between the NPD tool and the truer fixed on the end face of the aerostatic spindle to form a nose bite with a cutting-edge rounding radius, R, of 0.1 nm. However, it is common for operators to manually adjust the cut depth and the air pressure supplied to the aerostatic bearing by relying on the noise and rotation speed during machining. Moreover, aerostatic spindles without a control mechanism, such as active bearings, are widely used because of their low costs and versatility. For several years, the authors have been developing a method to control air bearing stiffness by controlling the bearing supply pressure with high speeds and precision using a high-precision quick response regulator for aerostatic spindles without a control mechanism, such as active bearings. In this study, the compliance control (control of spindle position and stiffness) of aerostatic bearings was investigated using the proposed method, and the effectiveness of the method to ultraprecision grinding applications was demonstrated.
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Obolenskiy, V. "Foreign Trade of Russia: Barometer Foretells Storm." World Economy and International Relations 60, no. 2 (2016): 15–25. http://dx.doi.org/10.20542/0131-2227-2016-60-2-15-25.
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The development of Russian foreign trade during the previous five years is analyzed. It is stated that, in terms of value, exports of services and imports of goods and services steadily grew during the first four years of the period under review. Exports of goods also rose during three years, but in 2014 both exports and imports again fell in comparison with the previous year as was the case five years ago. The composition of the Russian exports and imports of goods did not change radically during the previous years. The main items of export are, as always, mineral products, metals and fertilizers. Import is prevailed by foodstuffs, chemicals and heavy engineering equipment. The current situation is featured by the reduction of world oil prices, slump of the domestic economy and war of sanctions with the Western countries. All this substantially impairs the conditions of Russia’s foreign trade activities and inhibits its development in the upcoming years. In the author’s view, the implementation of measures worked out by the government – correction of tariff liabilities before the WTO, redirecting of trade streams from the European to the Asian markets, import substitution and export support – will unlikely improve the situation. Revision of the liabilities before the WTO in the conditions of the decrease of the internal demand and serious devaluation of Ruble is considered as inappropriate and counterproductive. “Asiatic turn” is only capable to compensate to a certain respect the loss of supplies of some food products from Europe, but cannot fully offset the loss of potentialities of the acquisition of modern technologies and equipment from the developed countries. It is doubtful that it will be possible to dramatically cut the import dependence. It is necessary to replace many kinds of foreign goods, but it is impossible to implement a frontal substitution of import in all directions. Excessive stress on the import substitution might lead to the emergence of shortages and poorer availability of some goods at the internal market and, at the worst, to self-isolation and economic autarky. The attempts to build up an effective system of export support might be successful only in the conditions of the establishment of the large-scale production of goods and services which would be comparable with the foreign analogues in respect to the criteria of price and quality. Taking this into consideration the technological renovation of production processes, first of all in the manufacturing industry, and on this basis rising up of the competitiveness of plants and factories are the most important prerequisites for encouraging export activities and formation of the new export specialization of the country.
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Hečko, Dávid, Pavol Mičko, Michal Holubčík, and Andrej Kapjor. "Experimental Simulation of Hydrate Formation Process in a Circulating Device." Processes 9, no. 9 (August 28, 2021): 1529. http://dx.doi.org/10.3390/pr9091529.
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This paper focuses on the model of gas hydrate formation in an experimental device, which allows the circulation of the resulting mixture (water and gas) and significantly accelerates the process of hydrate formation in the laboratory. A 3D model was developed to better imagine the placement of individual parts of the device. The kinetics of hydrate formation were predicted from equilibrium values of chemical potentials. The aim of solving the equations of state gases in the mathematical model was to optimize the parameters involved in the formation of hydrates. The prediction of the mathematical model was verified by numerical simulation. The mathematical model and numerical simulation predict the chemical reaction evolving over time and determine the amount of crystallized water in the reactor. A remarkable finding is that the deviation of the model and simulation at the initiation the calculation of crystallized water starts at 76% and decreases over time to 2%. Subsequently, the number of moles of bound gas in the hydrate acquires the same percentage deviations. The amount of water supplied to the reactor is expressed by both methods identically with a maximum deviation of 0.10%. The different character is shown by the number of moles of gas remaining in the reactor. At the beginning of the calculation, the deviation of both methods is 0%, but over time the deviation slowly increases, and at the end it expresses the number of moles in the reactor with a deviation of 0.14%. By previous detection, we can confirm that the model successfully determines the amount of methane hydrate formed in the reactor of the experimental equipment. With the attached pictures from the realized experiment, we confirmed that the proposed method of hydrate production is tested and takes minutes. The article calculates the energy efficiency of natural gas hydrate in the proposed experimental device.
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Terasaki, F., H. Ohtani, A. Ikeda, and M. Nakanishi. "Steel Plates for Pressure Vessels in Sour Environment Applications." Proceedings of the Institution of Mechanical Engineers, Part A: Power and Process Engineering 200, no. 3 (August 1986): 141–58. http://dx.doi.org/10.1243/pime_proc_1986_200_021_02.
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It is well known that wet hydrogen sulphide (H2S) can cause embrittlement of steels, hydrogen induced cracking (HIC) and sulphide stress corrosion cracking (SSCC). Several fractures of pipelines handling sour crude oil or gas led to vigorous researches on these problems. As similar failures have also been experienced in petroleum refinery equipment, degradation of steel by hydrogen sulphide is now recognized as a serious environmental problem. The paper considers the mechanism and factors involved in HIC. This type of cracking occurs mainly in the parent steels. The susceptibility of steels to cracking is influenced strongly by inhomogeneities such as the shape and distribution of non-metallic inclusions, and segregation of alloying elements. These have a significant effect on HIC because they modify the microstructures in the segregated regions. With reference to environmental factors, these mainly concern the influence of H2S partial pressures, pH of the solutions and other phenomena relevant to the absorption of hydrogen by the steel. SSCC poses problems in weld zones. It can occur especially in heat affected zones (HAZ) with high hardnesses. Such cracking can be prevented by the control of hardness by a suitable selection of the chemical composition of the steel and the welding conditions. Nevertheless, countermeasures similar to those described for the prevention of HIC are necessary to prevent SSCC in HAZ even with relatively low hardness. Research on factors influencing HIC and SSCC has resulted in the development of steels which are highly resistant to wet H2S cracking. These steels have been supplied in plate form for pressure vessels. Experience has confirmed the good performance of welded constructions in aggressive service environments.
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Yaroshevsky, Vladislav, Valentyna Krutyakova, Volodymyr Belchenko, Semjons Ivanovs, and Volodymyr Bulgakov. "Development and Research of New Media Jet Aeration Scheme in a Loop Bioreactor Producing Microbiological Products." Acta Technologica Agriculturae 24, no. 3 (August 10, 2021): 124–28. http://dx.doi.org/10.2478/ata-2021-0021.
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Abstract Jet aeration loop reactors are widely used in the chemical industry due to their high mixing intensity, possibility of significant saturation of medium with gases, and simplicity of scaling the processes when passing from laboratory equipment to industrial designs. However, to ensure the necessary amount of air in standard jet aeration schemes with ejectors, high pressure of the medium (up to 6 bars) is required in the reactor loop. This paper presents a newly developed scheme of jet aeration, based on mixing the pressure flows of medium and air supplied to the ejector by individual blowers. Experiment results of the new water aeration scheme showed that, for the formation of suspended matter in the ejector with an air content of 2–20 l per 1 l of water, a pressure of 0.3 bar in the reactor loop at an air pressure of 1 bar is sufficient. This allows usage of low-pressure pump and compressor, which form the basis for the energy consumption reduction and creates prerequisites for lowering the shear loads on a crop. The medium aeration rate during experiments was 0.220–0.266 vvm. It was found that, for each mode of joint operation of pump and compressor, it is possible to maintain a constant aeration rate, which is not significantly affected by the flowrate regulation of medium in loop.
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Smolentsev, Vladislav, Alexej Kuzovkin, and Igor Drozdov. "Application of two-component technological media for surface processing with a high degree of curvature." MATEC Web of Conferences 224 (2018): 01018. http://dx.doi.org/10.1051/matecconf/201822401018.
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The final dimensional combined treatment with the application of an electric field by a tool in the form of unbound metal pellets of complex profile components used in aviation, rocket and space technology and in the oil and gas industry is considered. Such parts include impellers and the flowing component of the turbo-pump units, augers, impellers, where there are sections of variable curvature with limited access of the tool to the processing area. It is shown that the combination in a combined process of two-component technological media from current-carrying granules and an electrically conductive liquid medium supplied at high speed to the treatment zone allows to provide the required technological and operational processing parameters; the action of an electric field from a source with an increased voltage makes it possible to remotely perform a final dimensional processing of the pieces of metal parts with the creation of the required coldhardening against the impacts of solid granules; a combination of mechanical, chemical and magnetic impacts ensures obtaining a given profile accuracy, surface roughness. As a result, it is possible to increase the action and durability of important units of aerospace engineering and oil and gas equipment, and also to expand the area of technological use of the combined treatment method with unbound granules to component parts that are not accessible for processing by an integral tool. In the method under consideration, a universal granule tool is used which does not have a constant geometric shape and is capable of being delivered to the treatment zone through openings into parts whose dimensions are commensurable with the cross-section of the granules.
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Ross, D. "Power struggle [power supplies for portable equipment]." IEE Review 49, no. 7 (July 1, 2003): 34–38. http://dx.doi.org/10.1049/ir:20030705.
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&NA;. "New Online Medical Marketplace For Equipment and Supplies." Journal of Clinical Engineering 30, no. 2 (April 2005): 74–75. http://dx.doi.org/10.1097/00004669-200504000-00028.
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Некрасова, Н. І. "SUBJECTS OF PUBLIC ADMINISTRATION IN THE FIELD OF TURNOVER OF MEDICAL ENGINEERING AND MEDICAL PRODUCTS IN UKRAINE." Juridical science 1, no. 4(106) (April 2, 2020): 133–39. http://dx.doi.org/10.32844/2222-5374-2020-106-4-1.16.
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The relevance of the article is that the creation of a quality system of public administration in various spheres of society is a priority of the domestic public administration. In accordance with such areas, public administration in the field of circulation of medical equipment and medical supplies in Ukraine belongs, in particular, the administration is carried out through a system of state and non-state bodies. Accordingly, the subjects of public administration must create all the necessary conditions in our country to provide quality medical services and ensure the right of citizens to treatment and maintenance of life. In addition, before we begin to consider our issues, we need to clarify such legal concepts as "public administration", "public administration" and "as public administration". Thus, revealing the essence of the topic "Subjects of public administration in the field of circulation of medical equipment and medical supplies in Ukraine", we must consider the most important aspects of their activities and determine their list. The purpose of the article is to determine the main subjects of public administration in the field of circulation of medical equipment and medical goods in Ukraine on the basis of the works of legal scholars. It is determined that the State Service of Ukraine for Medicines and Drug Control as a subject of public administration in the field of circulation of medical equipment and medical supplies in Ukraine is one of the main bodies of public administration, which in accordance with its powers should control the circulation of medical equipment and goods for medical purposes in Ukraine, in particular, should also be introduced control over the electronic system of circulation of such funds (which should include all elements of their circulation - from the stage of creation to their disposal). Entities of public administration in the field of circulation of medical equipment and medical supplies in Ukraine are an organizational and structural set of administrative bodies that have legal authority to state interests in the import, production, supply and circulation of quality goods in the field of medical equipment and medical supplies.
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Evans, R. "Photovoltaic Developments in East Africa: BP Solar's Applications and Installations." Energy Exploration & Exploitation 7, no. 2 (April 1989): 128–34. http://dx.doi.org/10.1177/014459878900700206.
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Photovoltaic or solar electrical systems are a small but important and growing part of energy supplies in East Africa. BP Solar East Africa, based in Nairobi, supplies a range of photovoltanic powered equipment in Kenya and throughout East Africa. Typical applications are listed.
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Yang, Xiao Guang, Hong Xing Dong, and Xing Hua Zhang. "Simulating Pipe Reactor of Biological Growth in Single-Phase Laminar Flow Based on Computational Fluid Dynamics and Reaction Dynamics by OpenFOAM." Advanced Materials Research 557-559 (July 2012): 2279–82. http://dx.doi.org/10.4028/www.scientific.net/amr.557-559.2279.
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Pipe reactor simulation of biological growth was investigated based on computational fluid dynamics (CFD) and reaction dynamics in single-phase laminar incompressible flow with the open-source software, OpenFOAM. OpenFOAM supplied a kind of open structure, which made it convenient to add a suitable physical model with CFD equations according to the problem. In order to compute mass transfer and biological growth as a reaction with fluid flow, the component conservation equation was listed with Navier-Stokes equations. With the equations, a pipe reactor was simulated by our solver which was developed based on OpenFOAM. By the simulation, the pressure, velocity and component mass fraction can be obtained at different time and position, which is important to analyze equipments in chemical engineering. Although some details need to be considered such as the definition of reaction term, the boundary conditions, etc., reactor simulation with OpenFOAM has showed very large potential.
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Philips, J. C., J. W. Miller, W. C. Wernau, B. E. Tate, and M. H. Auerbach. "A High-Pyruvate Xanthan for EOR." Society of Petroleum Engineers Journal 25, no. 04 (August 1, 1985): 594–602. http://dx.doi.org/10.2118/10617-pa.
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Abstract High-pyruvate xanthan (HP xanthan) is produced by a proprietary strain of the Xanthomonas campestris proprietary strain of the Xanthomonas campestris organism and is available in the form of a 3 to 5 % broth or a 12 to 15 % concentrate. The liquid product is supplied commercially (FLOCON 4800 or 4800C (TM) from Pfizer Inc.) for use as a mobility control and Pfizer Inc.) for use as a mobility control and permeability reduction agent for micellar, water-thickened, and permeability reduction agent for micellar, water-thickened, and waterflood diversion projects. This paper deals with use of the product for mobility control. The biopolymer is similar in structure to other commercial xanthans but contains a significantly higher level of ketal-bound pyruvic acid. Assay methods, including those applicable pyruvic acid. Assay methods, including those applicable to field waters, are discussed. While dilute HP xanthan exhibits viscosity/ concentration profiles and pH sensitivities that are similar to other xanthans, it has superior tolerance to high levels of salinity and hardness. Injectivity, as measured by Millipore TM filtration, is not adversely affected by high levels of monovalent cations and magnesium ion. The presence of ferric ion produces severe filterability presence of ferric ion produces severe filterability deterioration, while problems with calcium and ferrous ions are less serious. Good filterability in the presence of iron or hardness cations is restored by use of certain chelating agents and surfactants. Sequential filtrations of HP xanthan and other xanthans have been carried out with various-size Millipore membranes. On this basis, the effective size of the HP-xanthan molecule was shown to be no larger than 0.2 mu m. Compatibilities of HP xanthan with biocities, oxygen scavengers, and surfactants are discussed, as is information demonstrating control of microbiological problems and field propagation of the biopolymer. Introduction Activity among U.S. petroleum producers in EOR has increased significantly in recent years as a result of windfall profit tax incentives and the increasing number of waterflooded reservoirs that are approaching the limits of economic viability. Xanthan gums and hydrolyzed polyacrylamides have been used for mobility control in polyacrylamides have been used for mobility control in nearly all chemical flood projects to date. The choice between polyacrylamide and xanthan for EOR depends on a number of factors. Both polymers require a biocide to ensure protection against microbial attack. Although xanthan is more expensive than polyacrylamide, it offers outstanding resistance to shear polyacrylamide, it offers outstanding resistance to shear degradation that is troublesome for polyacrylamides in low-permeability formations. Also, in contrast to polyacrylamides, xanthan is retained to a lesser extent on polyacrylamides, xanthan is retained to a lesser extent on formation rock and is largely insensitive to waters with high salt content. A significant percentage of fields targeted for future EOR processes contain brine of high salinity and/or high hardness; and with growing restrictions on freshwater supplies, field brines will be used increasingly as injection fluids. Early injectivity problems associated with solutions of solid xanthan have been alleviated through the use of readily diluted liquid products. products. HP xanthan is available commercially as a liquid broth or concentrate. Rheological and injectivity properties of the biopolymer, as they relate to mobility control, are discussed. Xanthan Structures Xanthan contains D-glucose, D-mannose, and D-glucuronic acid in the repeating pentasaccharide unit shown in Fig. 1. In addition to the constituent sugars, acetate groups and pyruvic acid ketals are found in the side chains, and it has been reported that xanthan rheological properties are dramatically affected by pyruvate content. Table 1 shows pyruvic acid content as pyruvate content. Table 1 shows pyruvic acid content as a function of the percent of side chains bearing the pyruvate ketal moiety. HP xanthan is unique among pyruvate ketal moiety. HP xanthan is unique among xanthans in that most of the side chains contain this functionality, with the resulting pyruvic acid content being approximately twice that of commercial solid xanthan. Broth Properties Broth viscosities, as a function of concentration (activity basis), for HP xanthan and a conventional xanthan broth are shown in Fig. 2. HP-xanthan broth has a distinctly lower viscosity than conventional broth, and at concentrations of 0.1% or higher, it exhibits substantially lower yield points. These factors enable more efficient mass transfer during the fermentation process and permit production of a higher-assay broth. production of a higher-assay broth. An aqueous concentrate of 12 to 15 % xanthan, which offers further improved economics by significant reduction in shipping costs, is now available commercially. While more viscous than broth (Brookfield viscosity 12,000 to 13,500 cp [12.0 to 13.5 Pas], No. 4 spindle, 30 rev/min), the concentrate flows smoothly and is readily pumped and diluted with the same field equipment used for handling the normal 3 to 5 % broth. SPEJ P. 594
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Yang, Xiao Guang, Hong Xing Dong, and Xing Hua Zhang. "Computational Mass Transfer Based on CFD with OpenFOAM in Single-Phase Flow." Applied Mechanics and Materials 145 (December 2011): 134–37. http://dx.doi.org/10.4028/www.scientific.net/amm.145.134.
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In this work computational mass transfer was investigated based on computational fluid dynamics (CFD) in single-phase flow with the open-source software, OpenFOAM. OpenFOAM supplied a kind of open structure, which made it convenient that a suitable physical model was added with CFD equations according to the problem. In order to compute mass transfer with fluid flow, the component conservation equation was listed with Navier-Stokes equations. With the equations, a pipe flow with mass transfer was simulated on the assumption that the fluid density is constant by our solver which was developed based on OpenFOAM. By the simulation, the pressure, velocity and component mass fraction can be easily obtained at different time and position, which is very important for the analysis of equipments in chemical engineering. Although some details need to be considered such as the change of density with composition, the boundary conditions and the affect of complex shape, computational mass transfer with OpenFOAM has showed very large potential to be applied in industry.
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JOVANOVIĆ, MILAN M. "SURVEY OF STATE-OF-THE-ART TECHNOLOGIES FOR COMPUTER–NETWORK SERVER AC/DC POWER SUPPLIES." Journal of Circuits, Systems and Computers 13, no. 03 (June 2004): 399–423. http://dx.doi.org/10.1142/s0218126604001659.
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Due to a continuously increasing power demand of computer–network server equipment, power supply manufacturers are faced with requirements for ac/dc server power supplies with significantly higher power densities. In this paper, circuit technologies and optimization techniques that are suitable for meeting these new power-density requirements are discussed. The focus of the paper is on single-phase, single-output ac/dc power supplies that are used to generate a dc-bus voltage in distributed power systems employed in high-end network servers and telecom systems.
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FEENEY, JOSEPH J. "Chemical Contamination Survivability of Equipment." Naval Engineers Journal 101, no. 2 (March 1989): 71–75. http://dx.doi.org/10.1111/j.1559-3584.1989.tb00694.x.
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de Perio, Marie A., Chad H. Dowell, Lisa J. Delaney, Lewis J. Radonovich, David T. Kuhar, Neil Gupta, Anita Patel, Satish K. Pillai, and Maryann D’Alessandro. "Strategies for Optimizing the Supply of N95 Filtering Facepiece Respirators During the Coronavirus Disease 2019 (COVID-19) Pandemic." Disaster Medicine and Public Health Preparedness 14, no. 5 (May 19, 2020): 658–69. http://dx.doi.org/10.1017/dmp.2020.160.
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ABSTRACTN95 respirators are personal protective equipment most often used to control exposures to infections transmitted via the airborne route. Supplies of N95 respirators can become depleted during pandemics or when otherwise in high demand. In this paper, we offer strategies for optimizing supplies of N95 respirators in health care settings while maximizing the level of protection offered to health care personnel when there is limited supply in the United States during the 2019 coronavirus disease pandemic. The strategies are intended for use by professionals who manage respiratory protection programs, occupational health services, and infection prevention programs in health care facilities to protect health care personnel from job-related risks of exposure to infectious respiratory illnesses. Consultation with federal, state, and local public health officials is also important. We use the framework of surge capacity and the occupational health and safety hierarchy of controls approach to discuss specific engineering control, administrative control, and personal protective equipment measures that may help in optimizing N95 respirator supplies.
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Fan, Hongqin, Hyoungkwan Kim, and Osmar R. Zaïane. "Data warehousing for construction equipment management." Canadian Journal of Civil Engineering 33, no. 12 (December 1, 2006): 1480–89. http://dx.doi.org/10.1139/l06-108.
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Equipment logistics, maintenance, and repair are important aspects of construction equipment management. A well-managed equipment fleet helps reduce downtime, as well as total maintenance and repair costs. With quickly growing fleets of equipment, large contractors tend to divert the maintenance and repair of equipment from equipment managers to project managers. As a result, the equipment managers shift their attention from operational-level decision-making to corporate-level strategic decision-making regarding equipment management, which is often a challenging job with the current equipment management system. This paper presents an equipment data warehouse and a prototype decision support system (DSS). The proposed equipment data warehouse enables equipment managers to visually analyze the equipment fleet data from different perspectives and at various level of details. The data-warehouse-based DSS facilitates high-level, fact-based decision-making regarding equipment logistics, supplies, maintenance, repair, and replacement and has higher levels of performance and flexibility than the current equipment management system.Key words: data warehouse, decision support system, equipment management, multidimensional modeling.
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Yue, Guoyou, and Boonsub Panichakarn. "A Review of the Research on Emergency Logistics for Tropical Cyclone Disasters in Guangxi." GATR Global Journal of Business Social Sciences Review 9, no. 2 (June 25, 2021): 128–42. http://dx.doi.org/10.35609/gjbssr.2021.9.2(3).
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Objective - The purpose of this paper is to find out the key research direction and disaster relief optimization method of governments and organizations at all levels in Guangxi to deal with tropical cyclone disasters. Methodology/Technique - In terms of research methods, most of the research results focus on the qualitative research of emergency logistics, and the results of quantitative research are relatively few, but there are many kinds of quantitative calculation methods. In terms of focus, the optimization methods of emergency supplies dispatching are studied more, but the forecast results of emergency supplies requirements are less. Finding - Through literature survey method and in-depth interview method, the research status of emergency logistics is reviewed and analyzed in four aspects: tropical cyclone disaster, basic theory and method of emergency logistics, emergency supplies requirements prediction and emergency supplies dispatching. Through literature combing, there are three main aspects of the discovery. In terms of disaster types, most of the existing research results pay more attention to earthquake, flood and other natural disasters emergency logistics treatment, the results of emergency logistics treatment for tropical cyclone disasters are less, and the results of emergency logistics treatment for tropical cyclone disasters in Guangxi are fewer. Novelty - By comparing and determining the future research direction of this study, we focus on the formation law of tropical cyclone disaster chain in Guangxi, the optimization treatment methods and practical applications of emergency supplies requirements prediction and emergency supplies dispatching. The research results provide theoretical and methodological guidance for governments and organizations at all levels in Guangxi to carry out tropical cyclone disaster relief, and also point out the research direction and focus for further research in the future. Type of Paper - Empirical. Keywords: Emergency Logistics; Tropical Cyclone Disasters; Emergency Supplies Requirements; Emergency Supplies Dispatching; Guangxi JEL Classification: N7, Q54. URI: http://gatrenterprise.com/GATRJournals/GJBSSR/vol9.2_3.html DOI: https://doi.org/10.35609/gjbssr.2021.9.2(3) Pages 128 – 142
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GREEK, BRUCE F. "Tightening Supplies Push Up Ethylene Price." Chemical & Engineering News 65, no. 39 (September 28, 1987): 9–10. http://dx.doi.org/10.1021/cen-v065n039.p009.
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Narahari Prasad, S., and M. Narayana Rao. "Stainless Steel - A Versatile Engineering Material for Critical Applications." Advanced Materials Research 794 (September 2013): 44–49. http://dx.doi.org/10.4028/www.scientific.net/amr.794.44.
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Stainless Steel is a family of versatile materials that has been put into a wide variety of application by mankind. Stainless steels are iron-based alloys containing minimum 12% chromium and upto 25% nickel with minor additions of carbon, nitrogen, molybdenum, tungsten, titanium, niobium, copper and selenium. It has a wide range of applications from small pins to the construction of automobiles, petrochemical, space, aeronautical, ship building industries, nuclear and thermal power stations. Certain grades of stainless steels, because of their biocompatibility are used for manufacture of biomedical implants. In fact steel touches every sphere of our daily life. By and large stainless steel family consists of hundreds of grades with varieties of compositions and a large spectrum of mechanical properties. The corrosion and oxidation resistance of stainless steels have been significantly improved through fine-tuned chemical compositions and microstructural constituents, leading to the evolution of super stainless steels. Stainless steel development from design to application is a long-term continuous effort. The recent advances in stainless steels are mainly due to new ways of manufacture, processing and usage of advanced equipments. In spite of inroads by a range of competing materials, stainless steels occupy an important place as structural materials, because of their outstanding strength to weight ratios, ductility, fracture toughness, repairability, corrosion, etc for a given cost. Over the years, MIDHANI has catered to the requirements of Indian Space, Nuclear, Thermal, aeronautical and Defence sector for many high performance materials. A wide range of special stainless steels many of them being tailor made to customers specific needs have been developed and supplied. This has been possible with the help of state of the art facility and excellent quality assurance system available in MIDHANI. The presentation will high light MIDHANI role in development and commercial production of different varieties of stainless steels for critical applications.
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Simonovich, Shannon D., Elizabeth Aquino, Christina Lattner, Cheryl Soco, Tiffany N. Ponder, Lily Amer, Stephanie Howard, et al. "US Nurses’ Challenges with Personal Protective Equipment during COVID-19: Interview Findings from the Frontline Workforce." Psych 4, no. 2 (April 22, 2022): 226–37. http://dx.doi.org/10.3390/psych4020019.
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This study aimed to describe nurses’ experiences with personal protective equipment while providing patient care during the first wave of the COVID-19 pandemic in the US. From May 2020 to September 2020, 100 individual interviews were conducted with nurses from diverse backgrounds and practice settings. Interviews were audio-recorded, transcribed, and verified for thematic analysis. Three key themes emerged related to personal protective equipment during COVID-19: (1) concerns with safety, (2) concerns with personal protective equipment supply, and (3) concerns with health care systems changing personal protective equipment policies. These findings support the importance of transparent and equitable institution-wide PPE standards in creating safe working environments. Clear communication around personal protective equipment policies and procedures, personal protective equipment education, and assurance of equitable access to equipment that can mitigate risk and disability while also reducing fear, confusion, and frustration among nurses. Maintaining clear and consistent personal protective equipment guidelines and communication regarding supplies and procedures enhances transparency during both routine and critical times de-escalating the inevitable strain concomitant with providing patient care during a global pandemic.
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Liu, Hualiang. "An Overview of Intelligent Building Systems and Construction Debugging Techniques." World Construction 3, no. 1 (August 26, 2014): 11. http://dx.doi.org/10.18686/wc.v3i1.35.
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The implementation of the intelligent building of the general contractor in charge of the project construction drawings installation and testing design, equipment, materials, supplies and transportation, pipeline construction, equipment, system debugging through the acceptance of the relevant opening and administration until delivery. Composition and engineering techniques. This paper describes the architecture of intelligent systems and concluded that the implementation of intelligent building elements
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Liu, Hualiang. "An Overview of Intelligent Building Systems and Construction Debugging Techniques." World Construction 3 (August 26, 2014): 11. http://dx.doi.org/10.18686/wcj.v3i1.4.
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The implementation of the intelligent building of the general contractor in charge of the project construction drawings installation and testing design, equipment, materials, supplies and transportation, pipeline construction, equipment, system debugging through the acceptance of the relevant opening and administration until delivery. Composition and engineering techniques. This paper describes the architecture of intelligent systems and concluded that the implementation of intelligent building elements
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Corner, G. A., G. D. Currie, A. L. Evans, and R. Railton. "Quality of electrical mains supplies in hospitals: Implications for microprocessor-controlled medical equipment." Medical & Biological Engineering & Computing 31, no. 4 (July 1993): 438–44. http://dx.doi.org/10.1007/bf02446703.
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Dubrovina, Natalya A. "Innovative development of domestic engineering in the context of international sanctions: regional aspect." Vestnik of Samara University. Economics and Management 13, no. 4 (January 24, 2023): 7–15. http://dx.doi.org/10.18287/2542-0461-2022-13-4-7-15.
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The presented article considers the current economic situation, taking into account the restrictions of imported supplies of products, equipment and technologies. The need to develop domestic engineering in the field of high-tech equipment production, to create a powerful innovation and technological potential on the basis of enterprises producing modern machines and developing advanced technologies is justified. The trend in the development of mechanical engineering in one of the industrialized regions the Samara region was analyzed. It was revealed that the main supplier of machinery and equipment to the domestic market today is a domestic manufacturer, the production capacity of which in some sub-industries operates at the limit. In this regard, a significant increase in investments in the renewal of fixed assets is necessary. The increase in the production of innovative high-tech equipment is associated with significant investments and serious time costs, even if financing is carried out from the federal budget. The reason for the weak investment activity of enterprises is the low profitability of production and an unstable external environment. The priority should be the development and development of innovative equipment that meets the modern requirements of the innovative and technological development of industry.
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Tungcul, Mignonette B., and Marifel Grace Capili Kummer. "Supplies and Equipment Inventory, Monitoring and Tracking Management System using Data Mining Techniques." International Journal of Recent Technology and Engineering (IJRTE) 10, no. 2 (July 30, 2021): 81–85. http://dx.doi.org/10.35940/ijrte.b6174.0710221.
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In the present time, there are lot of web and software developer who provides different types of databased and online system to ease the burden of the different supply officer’s/inventory officers of different companies and government sectors but Cagayan State University is one of the big universities that remained inventory management in a manual way. This study together with the development of SEIMTMS was conducted to innovate the current system used and to abolish the difficulties and challenges encountered by the Supply Office staffs in inventory management, record keeping, monitoring and tracking, and report generation. Classification and clustering techniques were utilized to produce information and comprehensive decision support reports that aids the Supply Officer and University administration on decision- making and budget allocation. Furthermore, the system used Clustering technique together with MFP algorithm to forecast the frequently purchased supplies and frequently repaired equipment. These decision support reports are essential for Office Heads in identifying items to be purchased for a particular quarter. With the use of ISO/IEC 25010:2011 Software Quality Standards, the system was evaluated by IT Experts with a mean 4.67, qualitatively described as “very graet extent”.