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Continuous production of biodiesel from cottonseed oil and methanol using a column reactor packed with calcined sodium silicate base catalyst

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Chinese Journal of Chemical Engineering 2016年第4期24卷 499-505页

作者： xia Gui Sichen Chen zhi Yun College of Chemistry and Chemical Engineering Nanjing Tech University

Sodium silicate and that calcined at 400℃ for 2 h were used to catalyze the transesterification of cottonseed oil with methanol. Calcined sodium silicate （CSS） catalyst exhibited much higher catalytic activity and stability. A maximum biodiesel yield of 98.9~ was achieved at methanol/oil mole ratio of 12：1, reaction temperature 65℃, reaction time 3.0 h, and CSS/oil mass ratio of 2 Wffo. After 7 consecutive reactions without any treatment, biodiesel yield reduced to 82.5%. Considering technological and economic feasibility, CSS base catalyst supported on 0 rings was prepared for continuous transesterification. The maximum yield was 99.1% under optimum conditions （reaction temperature 55 ~C, methanol velocity 1 ml. rain- 1, oil velocity 3 ml- rain- 1, and 5 tower sec- tions）. These results indicate that this new continuous biodiesel production process and apparatus present a great potential for industrial application in biodiesel.

关键词： TransesterificationCottonseed oilCalcined sodium silicateBiodieselSodium silicateContinuous production

Feature analysis on US military aircraft engine advanced technology programs

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航空动力学报 2014年第7期29卷 1701-1709页

作者： LIANG Chun-hua SUN ming-xia LIU Hong-xia Shenyang Engine Design and Research Institute Aviation Industry Corporation of China

US military aircraft engine advanced technology programs were overviewed and analyzed from light weight gas generator(LWGG)program initiated in 1960 sthrough integrated high performance turbine engine technology(IHPTET)program started in 1980 s,then to versatile affordable advanced turbine engine(VAATE)*** features and trends were summarized and concluded by literature statistics method,such as teams based on closely corporation among government,industries and academics,goals oriented with national defence strategies and weapon system development requirements,engineering manufacture and development including all relative disciplines and areas,verification measured by technology readiness level,the application extending to military aircraft engine,civilian engine,gas turbine and space vehicle,*** experience and lessons obtained can provide reference and guide for technology research and engineering manufacture and development of military aircraft engines in the world.

关键词： aircraft engine military aircraft engine advanced technology program technology corporation multi-discipline development technology verification

Preparation and application of graphene-based wearable sensors

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Nano Research 2022年第11期15卷 9850-9865页

作者： Shan xia ming Wang Guanghui Gao Polymeric and Soft Materials Laboratory School of Chemical Engineering and Advanced Institute of Materials ScienceChangchun University of TechnologyChangchun 130012China Beijing Graphene Institute(BGI) Beijing 100871China

With the development of digital healthcare technology,the demand for non-invasive monitoring of human health is rapidly *** recent years,the research and application of timely,economical,and easy-to-operate wearable sensing devices have attracted much *** recent studies,graphene has been widely used to improve the sensing performance of wearable sensors due to its advantages in mechanical,electrical,and thermal *** review mainly focuses on summarizing graphene and its derivative-based wearable sensors and their latest developments in personal health *** will first introduce the novel structure and sensing mechanism of different types of graphene ***,we summarize the latest applications of the graphene wearable sensors in human health monitoring,including human activity,heart rate,pulse,electrophysiological signal,and electronic ***,the future challenges and prospects of graphene wearable devices will be discussed.

关键词： graphene sensor health monitoring physiological signal electronic skin

Repellent,larvicidal and adulticidal activities of essential oil from Dai medicinal plant Zingiber cassumunar against Aedes albopictus

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Plant Diversity 2021年第4期43卷 317-323页

作者： ming-xiang Li Yong-Peng Ma Hong-xia Zhang Hong-Zheng Sun Hong-Hai Su Sheng-Ji Pei zhi-zhi Du Key Laboratory of Economic Plants and Biotechnology Yunnan Key Laboratory for Wild Plant ResourcesKunming Institute of BotanyChinese Academy of SciencesKunming650201China University of Chinese Academy of Sciences Beijing100049China Kunming City Center for Disease Control and Prevention Kunming650034China

Zingiber cassumunar is an important plant used in traditional medicine and as a natural mosquito ***,the compounds responsible for the repellent activity of the plant are still *** aim of the study is to identify the components of *** essential oil that show repellent activity against Aedes *** also evaluated the larvicidal and adulticidal activities of *** essential oil against ***-cage mosquito repellent experiments showed that *** essential oil possessed moderate repellent activity with a minimum effective dose(MED)of 0.16±0.01 mg/cm^(20,compared to reference standard N,N-diethyl-3-methylbenzamide(DEET,0.03±0.01 mg/cm^(20).Bioassay-guided fractionation identified the major active compound of *** essential oil as(-)-terpinen-4-ol(1)(MED:0.19±0 mg/cm^(20).We also found that *** essential oil showed moderate larvicidal activity against first instar larvae of *** with a LC50(50%lethal concentration)of 44.9 mg/L after 24 *** bioassays showed that *** essential oil exhibits moderate adulticidal activity against *** with a LC50 of 5.44%,while(-)-terpinen-4-ol showed significant adulticidal activity with a LC50 of 2.10%after 24 *** study verifies that the *** essential oil has mosquito repellent activity,and that(-)-terpinen-4-ol is mainly responsible for this ***,this study provides scientific support for the folk usage of *** essential oil as mosquito repellent and indicates that *** essential oil and(-)-terpinen-4-ol can be used as plant-derived repellents and insecticides for mosquito control.

关键词： Zingiber cassumunar Essential oil Repellent activity Larvicidal activity Adulticidal activity (-)-Terpinen-4-ol

Exact mobility edges and topological phase transition in two-dimensional non-Hermitian quasicrystals

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Science China(Physics,Mechanics & Astronomy) 2022年第2期65卷 82-90页

作者： zhi-Hao Xu Xu xia Shu Chen Institute of Theoretical Physics and State Key Laboratory of Quantum Optics and Quantum Optics Devices Shanxi UniversityTaiyuan 030006China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Chern Institute of Mathematics and LPMC Nankai UniversityTianjin 300071China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Yangtze River Delta Physics Research Center Liyang 213300China

The emergence of the mobility edge(ME)has been recognized as an important characteristic of Anderson *** difficulty in understanding the physics of the MEs in three-dimensional(3 D)systems from a microscopic image encourages the development of models in lower-dimensional systems that have exact *** most of the previous studies are concerned with one-dimensional(1 D)quasiperiodic systems,the analytic results that allow for an accurate understanding of two-dimensional(2 D)cases are *** this work,we disclose an exactly solvable 2 D quasicrystal model with parity-time(PT)symmetry displaying exact *** the thermodynamic limit,we unveil that the extended-localized transition point,observed at the PT symmetry breaking point,is topologically characterized by a hidden winding number defined in the dual *** coupling waveguide platform can be used to realize the 2 D non-Hermitian quasicrystal model,and the excitation dynamics can be used to detect the localization features.

关键词： quasicrystals mobility edges non-Hermitian systems localization properties

Characterization of Nanostructures in Acellular Cementum of Human Tooth Roots

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Chemical Research in Chinese Universities 2012年第5期28卷 916-920页

作者： GAO Yong-bo LIU ming-xia SUN zhi-qiang ZHANG Kai DONG Feng-xia SUN Hong-chen YANG Bai Department of Oral Pathology School of StomatologyJilin UniversityChangchun 130041P.R.China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012P.R.China

Determining the microstructure in human cementum might help us design new kinds of replacement materials for the treatment of teeth injury and disease. The authors characterized the nanostructures in the cementum of health human teeth via scanning electronic microscopy（SEM）. It was found that the acellular cementum is mainly composed of two kinds of nanostructures―inorganic nanoparticles and organic nanofibers. And the inorganic nanoparticles show a tendency to arrange along the organic nanofibers. Based on the micro-molding in capillary strategy, the distribution of organic component in acellular cementum was copied with UV curable resin. After removing the inorganic nanoparticles by acid etching, many isolated spindle shape nanopores were left in polymer, which su- ggested that the inorganic nanoparticles should have been isolated by the organic component in cementum, and should be oval or nanosheet in shape. We hope the present work could provide reference for the biomimetic preparation of tissue engineering materials, and help us design new types of tooth implant.

关键词： Acellular cementum Nanostructure Root dentin

Toughening mechanisms of a high-strength acicular ferrite steel heavy plate

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International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 567-572页

作者： zhi-qiang Cao Yan-ping Bao Zheng-hai xia Deng Luo Ai-min Guo Kai-ming Wu Engineering Research Institute University of Science and Technology Beijing Beijing 100083 China Research ＆ Development Center Xiangtan Iron and Steel Co. Ltd. Xiangtan 411101 China Hubei Province Key Laboratory for Systems Science on Metallurgical Processing Wuhan University of Science and Technology Wuhan 430081 China

An ultra-low carbon acicular ferrite steel heavy plate was obtained with an advanced thermo-mechanical control process-relaxed precipitation controlled transformation （TMCP-RPC） at xiangtan Steel, Valin Group. The heavy plate has a tensile strength of approximately 600 MPa with a lower yield ratio. The impact toughness of the heavy plate achieves 280 J at ？40°C. The fine-grained mixed microstructures of the heavy plate mainly consist of acicular ferrite, granular bainite, and polygonal ferrite. The high strength and excellent toughness of the heavy plate are attributed to the formation of acicular ferrite microstructure. The prevention of blocks of martensite/retained austenite （M/A） and the higher cleanness are also responsible for the superior toughness.

关键词： high-strength steel microstructure mechanical properties acicular ferrite

Laves Phase Formation and Its Effect on Mechanical Properties in P91 Steel

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Acta Metallurgica Sinica(English Letters) 2015年第10期28卷 1238-1246页

作者： zhi-Xin xia Chuan-Yang Wang Yan-Fen Zhao Guo-Dong Zhang Lu Zhang Xin-ming Meng Shagang School of Iron and Steel Soochow University School of Mechanical and Electric Engineering Soochow University Suzhou Nuclear Power Research Institute

Effect of Laves phase formation on mechanical properties in a pressurized T-junction of P91 steel pipe at849 K for 58,000 h with 25.65 MPa vapor pressure was studied. Thermodynamic calculations had been performed by using the software Thermo-Calc to study the phase at equilibrium state. Counter plot of von Mises stress in the pipe during service life was calculated by finite element analysis to study the effect of the operated stress distribution on the evolution of Laves phase. The change in the microstructure and mechanical properties in the sites with different stress was also studied. The results indicated that the formation of Laves phase in P91 steel was a thermodynamically possible process due to enrichment of Mo and depletion of C adjacent to M23C6 particles or along martensite lath and packet boundaries. The formation of Laves phase had a detrimental influence on the mechanical properties in P91 steel. The mean size of Laves phase would be significantly increased with increasing operated stress, leading to a reduction in tensile properties and impact energy. In particular, crack initiation energy and crack growth energy during impact test rapidly decreased with increasing the mean size and volume fraction of Laves phase.

关键词： Heat-resistant steels Laves phase Creep Precipitation Phase stability

Efficient Scheme for Entanglement and Quantum Information Processing with Two Superconducting Quantum-Interference Devices in Cavity QED

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Communications in Theoretical Physics 2007年第4期47卷 722-724页

作者： ZHAN zhi-ming School of Physics ＆ Information Engineering Jianghan University Wuhan 430056 China

In this paper, a scheme is proposed to create the entanglement of two superconducting quantum-interference devices （SQUIDs） and implement a two-quhit quantum phase gate between two SQUIDs in cavity. The scheme only requires resonant interactions. Thus the scheme is very simple and the quantum dynamics operation can he realized at a high speed, which is important in view of decoherence.

关键词： entanglement superconducting cavity