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Synthesis of refrigeration system based on generalized disjunctive programming model

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Chinese Journal of Chemical Engineering 2018年第8期26卷 1613-1620页

作者： Danlei Chen Xue ma Yiqing Luo yingjie ma Xigang Yuan School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China State Key Laboratory of Chemical Enineering Tianjin University Tianjin 300072China

Refrigeration system holds an important role in process industries. The optimal synthesis cannot only reduce the energy consumption, but also save the production costs. In this study, a general methodology is developed for the optimal design of refrigeration cycle and heat exchanger network(HEN) simultaneously. Taking the heat integration between the external heat sources/sinks and the refrigeration cycle into consideration, a superstructure with sub-coolers is developed. Through defining logical variables that indicate the relative temperature positions of refrigerant streams after sub-coolers, the synthesis is formulated as a Generalized Disjunctive Programming(GDP) problem based on LP transshipment model, with the target of minimizing the total compressor shaft work in the refrigeration system. The GDP model is then reformulated as a Mixed Integer Nonlinear Programming(MINLP) problem with the aid of binary variables and Big-M Constraint Method. The efficacy of the process synthesis model is demonstrated by a case study of ethylene refrigeration system. The result shows that the optimization can significantly reduce the exergy loss as well as the total compression shaft work.

关键词： Refrigeration system Process synthesis Generalized Disjunctive Programming (GDP) Mixed Integer Nonlinear Programming (MINLP)

Optimal synthesis of compression refrigeration system using a novel MINLP approach

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Chinese Journal of Chemical Engineering 2018年第8期26卷 1662-1669页

作者： Tao Yang Yiqing Luo yingjie ma Xigang Yuan School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China State Key Laboratory of Chemical Engineering Tianjin University Tianjin 300072China

The optimal design of a compression refrigeration system(CRS) with multiple temperature levels is very important to chemical process industries and also represents considerable challenges in process systems engineering. In this paper, a general methodology for the optimal synthesis of the CRS, which simultaneously integrates CRS and Heat Exchanger Networks(HEN) to minimize the total compressor shaft work consumption based on an MINLP model, has been proposed. The major contribution of this method is in addressing the optimal design of refrigeration cycle with variable refrigeration temperature levels. The method can be used to make major decisions in the CRS design, such as the number of levels, temperature levels, and heat transfer duties. The performance of the developed methodology has been illustrated with a case study of an ethylene CRS in an industrial ethylene plant, and the optimal solution has been examined by rigorous simulations in Aspen Plus to verify its feasibility and consistency.

关键词： Optimal design Compression refrigeration system (CRS) Chemical process Process systems Compressor shaft work Mixed Integer Nonlinear Programming (MINLP)

Solvothermal Synthesis of Boehmite and γ-Alumina Nanorods

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Journal of materials Science & Technology 2008年第4期24卷 637-640页

作者： Mingguo ma yingjie ZHU Guofeng CHENG Yuehong HUANG State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

Boehmite nanorods were synthesized by a solvothermal method using AICl3·6H2O in mixed solvents of water and aniline. The solvothermal time, heating temperature and the concentration of aniline have effects on the morphology of boehmite. γ-alumina nanorods were prepared by a simple thermal transformation of boehmite nanorods. A rational mechanism based on the oriented attachment is proposed for the formation of boehmite nanorods. The products were characterized by X-ray powder diffraction （XRD） and transmission electron microscopy （TEM）. Photoluminescence （PL） spectrum of the boehmite nanorods was also investigated.

关键词： Boehmite γ-Alumina Nanorods Solvothermal

Cascading V_(2)O_(3)/N-doped carbon hybrid nanosheets as high-performance cathode materials for aqueous zinc-ion batteries

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Chinese Chemical Letters 2022年第3期33卷 1430-1434页

作者： Yue Niu Denghui Wang yingjie ma Linjie Zhi CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100039China

In recent years, especially when there is increasing concern about the safety issue of lithium-ion batteries (LIBs), aqueous Zn-ion batteries (ZIBs) have been getting a lot of attention because of their cost-effectiveness, materials abundance, high safety, and ecological friendliness. Their working voltage and specific capacity are mainly determined by their cathode materials. Vanadium oxides are promising cathode materials for aqueous ZIBs owing to their low cost, abundant resources, and multivalence. However, vanadium oxide cathodes still suffer from unsatisfactory capacity, poor stability, and low electrical conductivity. In this work, cascading V_(2)O_(3)/nitrogen doped carbon (V_(2)O_(3)/NC) hybrid nanosheets are prepared for high-performance aqueous ZIBs by pyrolyzing pentyl viologen dibromide (PV) intercalated V_(2)O5 nanosheets. The unique structure features of V_(2)O_(3)/NC nanosheets, including thin sheet-like morphology, small crystalline V_(2)O_(3) nanoparticles, and conductive NC layers, endow V_(2)O_(3)/NC with superior performance compared to most of the reported vanadium oxide cathode materials for aqueous ZIBs. The V_(2)O_(3)/NC cathode exhibits the discharge capacity of 405 mah/g at 0.5 A/g, excellent rate capability (159 mah/g at 20 A/g), and outstanding cycling stability with 90% capacity retention over 4000 cycles at 20 A/g.

关键词： Aqueous zinc ion batteries Cathode materials Vanadium oxides Nitrogen doped carbon 2D nanosheets High performance

WBZUC:novel white-box ZUC-128 stream cipher

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The Journal of China Universities of Posts and Telecommunications 2023年第2期30卷 96-106页

作者： Yang Yatao Zhang Ruoqing Dong hui ma yingjie Zhang Xiaowei Department of Electronic and Communication Engineering Beijing Electronic Science and Technology InstituteBeijing 100070China School of Telecommunication Engineering Xidian UniversityXi'an 710071China Hong Kong Applied Science and Technology Research Institute Hong Kong 999077China

White-box cryptography is critical in a communication system to protect the secret key from being disclosed in a cryptographic algorithm code *** stream cipher is a main dataflow encryption approach in mobile ***,research work on white-box cryptographic implementation for stream cipher is rare.A new white-box Zu Chongzhi-128(ZUC-128)cryptographic implementation algorithm named WBZUC was *** adopts lookup table and random coding in the non-linear function to make the intermediate value chaotic without changing the final encryption ***,the WBZUC algorithm’s security gets improved compared with the original ZUC-128 *** for the efficiency,a test experiment on WBZUC shows that the average speed of key generation,encryption,and decryption can reach at 33.74 kbit/s,23.31 kbit/s,24.06 kbit/s *** its running speed is relatively a bit lower than original ZUC-128 algorithm,WBZUC can provide better security and comprehensive performance in mobile communication system environment.

关键词： Zu Chongzhi-128(ZUC-128)algorithm white-box cryptography cryptographic implementation lookup table secure communication

Effect of hydrogen charging on microstructural evolution and corrosion behavior of Ti-4Al-2V-1Mo-1Fe alloy

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Journal of materials Science & Technology 2021年第1期60卷 168-176页

作者： Yanxin Qiao Daokui Xu Shuo Wang yingjie ma Jian Chen Yuxin Wang Huiling Zhou School of materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Key Laboratory of Nuclear materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of materials Science and Engineering Northeastern UniversityShenyang 110004China

The effect of hydro gen charging on microstructural evolution and corrosion behavior of a Ti-4Al-2V-1Mo-1Fe alloy in a 3.5 wt.% NaCl solution was *** results showed that the hydrogen charging induced the formation and growth of γ-TiH and δ-TiH_(2) phases,leading to the initiation and propagation of hydrogen-induced *** was also found that hydrogen charging can change the passivity of this alloy and increase its pitting corrosion *** main reason for these was attributed to the fo rmation of hydrides in α phase in the Ti-4Al-2V-1Mo-1Fe alloy,leading to the preferential dissolution of the α phase and thus the deterioration in the protective ability of passive film.

关键词： Titanium alloy Hydrogen Microstructure Corrosion Electrochemical

Controllable growth of GeSi nanostructures by molecular beam epitaxy

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Journal of Semiconductors 2018年第6期39卷 51-65页

作者： yingjie ma Tong Zhou Zhenyang Zhong Zuimin Jiang State Key Laboratory of Functional materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences State Key Laboratory of Surface Physics Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education) and Department of PhysicsFudan University School of Physics and Optoelectronic Engineering Shandong University of Technology

We present an overview on the recent progress achieved on the controllable growth of diverse GeSi al- loy nanostructures by molecular beam epitaxy. Prevailing theories for controlled growth of Ge nanostructures on patterned as well as inclined Si surfaces are outlined firstly, followed by reviews on the preferential growth of Ge nanoislands on patterned Si substrates, Ge nanowires and high density nanoislands grown on inclined Si surfaces, and the readily tunable Ge nanostructures on Si nanopillars. Ge nanostructures with controlled geometries, spatial distributions and densities, including two-dimensional ordered nanoislands, three-dimensional ordered quantum dot crystals, ordered nanorings, coupled quantum dot molecules, ordered nanowires and nanopillar alloys, are dis- cussed in detail. A single Ge quantum dot-photonic crystal microcavity coupled optical emission device demon- stration fabricated by using the preferentially grown Ge nanoisland technique is also introduced. Finally, we sum- marize the current technology status with a look at the future development trends and application challenges for controllable growth of Ge nanostructures.

关键词： Ge Si molecular beam epitaxy nanostructures controllable patterned substrates inclinedsurfaces preferential growth

Influence of Processing Conditions on Microstructure and Mechanical Properties of Large Thin-Wall Centrifugal Ti–6Al–4V Casting

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Journal of materials Science & Technology 2016年第4期32卷 362-371页

作者： Xin Feng Jianke Qiu yingjie ma Jiafeng Lei Yuyou Cui Xinhua Wu Rui Yang Institute of Metal Research Chinese Academy of Sciences Department of materials Engineering Monash University

In this work, the effects of mould pre-heating temperatures and hot isostatic pressing （HIPping） process on the microstructural characteristics and mechanical properties, including static tensile and damage- tolerance properties of large thin-wall cylindrical Ti-6Al-4V casting, have been studied. The experimental results show that with the increasing mould pre-heating temperature from 673 to 873 K, the casting mi- crostructures change from a mixture of Widmanstatten and colony microstructure to a primary colony. The centre of the thick wall section has relatively coarse microstructure than the edge and thin section. Lower mould pre-heating temperature brings about more porosities. HIPping process, which not only reduces the casting pores effectively but also increases the prior β grain boundary cohesion and coars- ens the microstructure, is essential to improving the ductility of the casting. Due to the oxygen contamination and finer microstructure on the surface, micro-hardness profiles on the cross section present a decreas- ing tendency from the surface to inner. The thickness of the reaction layers for the different mould pre-heating temperatures is nearly the same （-450 μm）. On the whole, the tensile strength and micro- hardness decrease with increasing mould pre-heating temperature from 673 to 873 K. However, the fracture toughness and fatigue crack growth resistance of the castings increase with increasing mould pre- heating temperature.

关键词： Ti-6Al-4V alloyCentrifugal investment castingHot isostatic pressingCasting microstructureTensile propertiesDamage-tolerance properties

Isozyme　changes　during　larval　development　of　Penaeus　chinensis

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Acta Oceanologica Sinica 1997年第2期16卷 215-224页

作者： Zhang, Zhifeng ma, yingjie Liao, Chengyi Wang, Hailin College of marine Life Sciences Ocean University of Qingdao Qingdao 266003 China

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关键词： larval Penaeus changes chinensis development Isozyme