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11.
K. Przewlocki L. Petryka Z. Stḙgowski 《Isotopes in environmental and health studies》2013,49(9):439-444
One of the most difficult operations for control and identification in copper ore concentration process is grain classification in hydrocyclone batteries. In the paper radiotracer investigations of the classification process immediately give values of hydrocyclones parameters with higher accuracy than obtained from conventional methods. Presented paper includes the results of the investigation which was carried out in “Lubin” Copper Mine in Poland. 相似文献
12.
针对三维调整机难以实现多台同步工作,设计了基于PLC的同步控制方案。在同步控制系统方案中,采用西门子PLC通过工业无线以太网进行同步控制,由各维度油缸的位移传感器来保证同步控制的精确性。经实验,证实了此系统的精度满足设计要求,实现了同步控制的效果。 相似文献
13.
Shuhao Zhang Mercedes K. Taylor Lingchang Jiang Prof. Hao Ren Prof. Guangshan Zhu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(15):3205-3221
Light hydrocarbons (C1–C3) are used as basic energy feedstocks and as commodity organic compounds for the production of many industrially necessary chemicals. Due to the nature of the raw materials and production processes, light hydrocarbons are generated as mixtures, but the high-purity single-component products are of vital importance to the petrochemical industry. Consequently, the separation of these C1–C3 products is a crucial industrial procedure that comprises a significant share of the total global energy consumption per year. As a complement to traditional separation methods (distillation, partial hydrogenation, etc.), adsorptive separations using porous solids have received widespread attention due to their lower energy costs and higher efficiency. Extensive research has been devoted to the use of porous materials such as zeolites and metal-organic frameworks (MOFs) as solid adsorbents for these key separations, owing to the high porosity, tunable pore structures, and unsaturated metal sites present in these materials. Recently, porous organic framework (POF) materials composed of organic building blocks linked by covalent bonds have also shown excellent properties in light hydrocarbon adsorption and separation, sparking interest in the use of these materials as adsorbents in separation processes. This Minireview summarizes the recent advances in the use of POFs for light hydrocarbon separations, including the separation of mixtures of methane/ethane, methane/propane, ethylene/ethane, acetylene/ethylene, and propylene/propane, while highlighting the relationships between the structural features of these materials and their separation performances. Finally, the difficulties, challenges, and opportunities associated with leveraging POFs for light hydrocarbon separations are discussed to conclude the review. 相似文献
14.
《Analytical letters》2012,45(10):1941-1959
Abstract This paper describes a third order derivative mole cular absorption spectrophotometric procedure for the deter mination of traces of mercury based on the formation of ternary ion-association complex by reaction of mercury with pyronine G in the presence of iodide. The pink coloured ternary ion-association complex is readily formed in the pH range 1–7 and remained stable for 24 h. after stabilization with gelatin. The influence of various instru mental parameters and reaction conditions for maximum color development are discussed. The few interfering ions can be masked by the addition of appropriate reagent solutions. 相似文献
15.
The HNO3‐mediated CH2 extrusion reactions of phenylacetic acid lead to one pot synthesis of unexpected commercially important product 4‐nitrobenzoic acid through the formation of 4‐nitrophenylacetic acid and 2‐nitrophenylacetic acid. 相似文献
16.
Naveen Kumar 《Journal of Dispersion Science and Technology》2014,35(2):205-214
Dimeric surfactants also known as gemini surfactants have received lots of attention for high performance formulations in the various scientific and commercial products. Due to the greater amount of hydrocarbon per molecule, the critical micelle concentrations (CMC) of dimeric are typically one order of magnitude lower than the corresponding monomeric surfactant. They are ten to hundred times more efficient at reducing the surface tension of water and the interfacial tension of the oil-water interface than conventional surfactants. Besides, the Krafft temperatures of gemini surfactants with hydrophilic spacers are generally very low giving these surfactants the capacity to be used in cold water. These surfactants display a range of interesting properties, including elevated surface activity, extremely low CMC and extraordinary rheology and self-assimilation aspect. As a consequence of these properties, they have many potential applications include detergents and cleaning agents, cosmetics, textile, and dyeing, dispersion stabilization and emulsion polymerization, genetics science, pharmaceutical, and biological applications. 相似文献
17.
本文介绍了我国中长期发展规划中所制定的化学化工学科发展目标,综述了化学工程学科近十余年来在队伍建设、平台建设和国家级奖励等方面所取得的成果,列举了若干化学工程在传递与过程强化、化工分离过程、精细与药物化工、能源化工和材料化工领域从基础研究到工业化应用的例子和成果,展望了化学工程学科今后发展的方向及目标. 相似文献
18.
Dingzhong Li Wensheng Zhang Dr. Longzhi Zhu Prof. Dr. Shuang-Feng Yin Prof. Dr. Nobuaki Kambe Prof. Dr. Renhua Qiu 《ChemistryOpen》2022,11(5):e202200023
An efficient hydrazine substitution of p-nitro-aryl fluorides with hydrazine hydrates catalyzed by FeO(OH)@C nanoparticles is described. This hydrazine substitutions of p-nitro-aryl fluorides bearing electron-withdrawing groups proceeded efficiently with high yield and selectivity. Similarly, hydrogenations of p-nitro-aryl fluorides containing electron-donating groups also smoothly proceeded under mild conditions. Furthermore, with these prepared aryl hydrazines, some phthalazinones, interesting as potential structures for pharmaceuticals, have successfully been synthesized in high yields. 相似文献
19.
Rosana A. Gonalves Rosimara P. Toledo Nirav Joshi Olivia M. Berengue 《Molecules (Basel, Switzerland)》2021,26(8)
Over the last two decades, oxide nanostructures have been continuously evaluated and used in many technological applications. The advancement of the controlled synthesis approach to design desired morphology is a fundamental key to the discipline of material science and nanotechnology. These nanostructures can be prepared via different physical and chemical methods; however, a green and ecofriendly synthesis approach is a promising way to produce these nanostructures with desired properties with less risk of hazardous chemicals. In this regard, ZnO and TiO2 nanostructures are prominent candidates for various applications. Moreover, they are more efficient, non-toxic, and cost-effective. This review mainly focuses on the recent state-of-the-art advancements in the green synthesis approach for ZnO and TiO2 nanostructures and their applications. The first section summarizes the green synthesis approach to synthesize ZnO and TiO2 nanostructures via different routes such as solvothermal, hydrothermal, co-precipitation, and sol-gel using biological systems that are based on the principles of green chemistry. The second section demonstrates the application of ZnO and TiO2 nanostructures. The review also discusses the problems and future perspectives of green synthesis methods and the related issues posed and overlooked by the scientific community on the green approach to nanostructure oxides. 相似文献
20.
Konstantinos Petrotos Ioannis Giavasis Konstantinos Gerasopoulos Chrysanthi Mitsagga Chryssoula Papaioannou Paschalis Gkoutsidis 《Molecules (Basel, Switzerland)》2021,26(1)
Orange pomace (OP) is a solid waste produced in bulk as a byproduct of the orange juice industry and accounts for approximately 50% of the quantity of the fruits processed into juice. In numerous literature references there is information about diverse uses of orange pomace for the production of high-added-value products including production of natural antioxidant and antimicrobial extracts rich in polyphenols and flavonoids which can substitute the hazardous chemical antioxidants/antimicrobials used in agro-food and cosmetics sectors. In this work and for the first time, according to our knowledge, the eco-friendly aqueous vacuum microwave assisted extraction of orange pomace was investigated and optimized at real industrial scale in order to produce aqueous antioxidant/antimicrobial extracts. A Response Surface Optimization methodology with a multipoint historical data experimental design was employed to obtain the optimal values of the process parameters in order to achieve the maximum rates of extraction of OP total polyphenols and/or total flavonoids for economically optimum production at industrial scale. The three factors used for the optimization were: (a) microwave power (b) water to raw pomace ratio and (c) extraction time. Moreover, the effectiveness and statistical soundness of the derived cubic polynomial predictive models were verified by ANOVA. 相似文献