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Journal of Thermal Science 2020年第1期29卷 115-121页

作者： MA Xin tu Ran CHENG Xudong ZHU Shuguang SUN Qiang FANG Tingyong College of Environment and Energy Engineering Anhui Jianzhu UniversityHefei 230022China College of Mechanical Engineering and Automation Huaqiao UniversityXiamen 361021China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230026China

Rigid polyurethane(PUR)foam,a sustainable thermosetting building facade porous polymer material,has been widely applied in the construction industry for energy *** knowledge of the fire safety performance of PUR foam at different altitudes and sample widths is *** lab-scale experiments were conducted in the Lhasa plateau(66.5 kpa)and the Hefei plain(99.8 kpa)in *** propagation characteristics(average flame spread rate and flame height)were measured at different widths and atmospheric pressures of the test *** results show that the dependence of dimensionless flame heights on sample width shows negative power law relationships with index of−w/5.4 to−w/*** flame height and flame spread rate were lower under low ambient pressure conditions as H fP0.26~0.33 and VfP0.057~*** spread rate decreased with increasing sample width in the convection regime before a critical width of 4 cm–8 cm,after which the flame spread rate increased in the radiation *** of this study contribute to the science of combustion,fire safety and energy conservation,and provide a basis for fire safety protocols for historical heritage buildings in the Lhasa plateau.

关键词： rigid polyurethane low air pressure building facade energy conservation heat transfer

First integrals of the axisymmetric shape equation of lipid membranes

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Chinese Physics B 2018年第3期27卷 551-559页

作者： Yi-Heng Zhang Zachary McDargh Zhan-Chun tu Department of Physics Beijing Normal UniversityBeijing 100875China Department of Physics Carnegie Mellon University5000 Forbes AvenuePittsburgh PA 15213USA

The shape equation of lipid membranes is a fourth-order partial differential *** the axisymmetric condi-tion,this equation was transformed into a second-order ordinary differential equation(ODE)by Zheng and Liu(***.E 482856(1993)).Here we try to further reduce this second-order ODE to a first-order ***,we invert the usual process of variational calculus,that is,we construct a Lagrangian for which the ODE is the corresponding Euler-Lagrange ***,we seek symmetries of this Lagrangian according to the Noether *** a certain restriction on Lie groups of the shape equation,we find that the first integral only exists when the shape equation is identical to the Will-more equation,in which case the symmetry leading to the first integral is scale *** also obtain the mechanical interpretation of the first integral by using the membrane stress tensor.

关键词： lipid membrane shape equation first integral Noether theorem

DEPOSITION OF TiBN HARD FILMS ON HOT-WORKING-STEEL DIES FOR ALUMINIUM EXTRUSION VIA A DUPLEX PROCESS

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Acta Metallurgica Sinica(English Letters) 2001年第6期14卷 408-414页

作者： K. Muller (Forschungszentrum Stranpressen, tu Berlin, 13355 Berlin, Germany) Forschungszentrum Stranpressen TU Berlin 13355 Berlin Germany

Hot working steels have been used as die materials for hot extrusion of aluminium. Due to tribological interaction at elevated temperature between the die bearing and the surface of extruded aluminium profiles, not only the surface quality of the extruded product, but also the lifetime of the dies decreases. Deposition of TiBN hard films on the die bearing could improve the die performance. Treatment should be done in a duplex process process combining a plasma nitriding pretreatment (PN) and a plasma assisted chemical vapour deposition (paCVD) of TiBN. In this study the influence of the process conditions on the properties of the duplex coatings was investigated. The relationship between structure and mechanical property was researched. For testing these TIBN hard films under elevated temperature conditions and for comparison with other possible coatings special extrusion dies with different coated bearings were used. The extrusion trials were performed on the 8MN-extrusion press at the research a nd development center for extrusion, Technical University of Berlin.

关键词： hard film plasma nitriding duplex process PN pa CVD and extrusion

Credibility protection for resource sharing and collaborating in non-center network computing environments

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The Journal of China Universities of Posts and Telecommunications 2014年第3期21卷 46-55页

作者： XU Xiao-long tu Qun WANG Xin-heng WANG Ru-chuan College of Computer Nanjing University of Posts and Telecommunications State Key Laboratory for Novel Software Technology Nanjing University School of Computing University of the West of Scotland Paisley PA1 2BE United Kingdom

Non-center network computing environments have some unique characteristics, such as instability, heterogeneity, autonomy, distribution and openness, which bring serious issues of security and reliability. This article proposes a brand-new credibility protection mechanism for resource sharing and collaboration in non-center network computing environments. First, the three-dimensional hierarchical classified topology （3DHCT） is proposed, which provides a basic framework for realizations of the identity credibility, the behavior credibility and the capability credibility. Next, the agent technology is utilized to construct the credibility protection model. This article also proposes a new comprehensive credibility evaluation algorithm with simple, efficient, quantitative and able to meet the requirements of evaluating behavior credibility and the capability credibility evaluation as well. The Dempster-Shafer theory of evidence and the combination rule are used to achieve the evaluation of the capability credibility. The behavior credibility is evaluated with the current and historical performance of nodes for providers and consumers to realize more accurate prediction. Based on the non-center network computing simulation test platform, simulation is been conducted to test the performance and validity of the proposed algorithms. Experiment and analysis show that the proposed algorithms are suitable for large-scale, dynamic network computing environments, and able to maintain the credibility for networks without relying on central node, make a non-center network gradually evolve into an orderly, stable and reliable computing environment efficiently.

关键词： non-center network computing agent credibility evidence

The effects of repeated propofol anesthesia on spatial memory and long-term potentiation in infant rats under hypoxic conditions

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Genes & Diseases 2020年第2期7卷 245-252页

作者： Mang Sun Ruixue Yuan Hui Liu Jing Zhang Shengfen tu Department of Anesthesiology Children’s Hospital of Chongqing Medical UniversityChina Chongqing Key Laboratory of Pediatrics China China International Science and Technology Cooperation Base of Child Development and Critical Disorders China Department of Anesthesiology The First Affiliated Hospital of Chongqing Medical UniversityNo.Yixueyuan RoadYuzhong DistrictChongqing400016China Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering China

Propofol is widely used as an intravenous drug for induction and maintenance in general *** is a common complication during *** want to know the effect of propofol on spatial memory and LTP(Long-term potentiation)under hypoxic *** this study,84 seven-day-old SpragueeDawley rats were randomly assigned into six groups(n Z 14)-four control groups:lipid emulsion solvent t 50%oxygen(CO),lipid emulsion solvent t room air(CA),lipid emulsion solvent t 18%oxygen(CH),and propofol t 50%oxygen(propofoleoxygen,PO);and two experiment groups:propofol t room air(propofol eair,pa),and propofol t 18%oxygen(propofolehypoxia,PH).After receiving propofol(50 mg/kg)or the same volume of intralipid intraperitoneal(5.0 ml/kg),injected once per day for seven consecutive days,the rats were exposed to 18%oxygen,50%oxygen and air,until recovery of the righting *** found that the apoptotic index and activated caspase-3 increased in the PH group(Ppared with the pa group,fEPSP(field excitatory postsynaptic)potential and success induction rate of LTP reduced in all propofol groups(Ppared with the PO group,the fEPSP and success induction rate of LTP reduced significantly in the pa and PH groups(Ppared with CH group,the average time of escape latency was longer,and the number of platform location crossings was significantly reduced in the PH group(P<0.05).Thus,we believe that adequate oxygen is very important during propofol anesthesia.

关键词： Anesthesia Apoptosis Hypoxemia LTP Propofol Spatial memory

New progress in development of ferroelectric and piezoelectric nanoceramics

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Journal of Advanced Ceramics 2015年第1期4卷 1-21页

作者： Xiao-Hui WANG I-Wei CHEN Xiang-Yun DENG Yu-Di WANG Long-tu LI State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Department of Materials Science and Engineering University of PennsylvaniaPhiladelphiaPA 19104-6272USA

There has been great progress in the last decade in the synthesis of nanopowders with highly controlled size and size ***,the development of an unconventional pressureless two-step sintering strategy enabling densification without grain growth provides a novel technology suitable for commercial production of nanograin *** particular interest concerning bulk dense nanograin ceramics is the manifestation of ferroelectricity,which remains a fundamental issue to be understood and *** the best powder synthesis and optimized two-step sintering,high-density barium titanate(BT)and related nanograin ceramics have been fabricated to allow for a detailed determination of the size effect on nanometer-scale ferroelectricity and piezoelectricity of fundamental and industrial *** include dense ceramics of undoped BT with an average grain size down to 5 nm,and of(1x)BiScO_(3)xPbTiO_(3)(BSPT)solid solutions with an average grain size down to 10 *** we review the fabrication methods of high-density BT and BSPT nanoceramics and the major findings of the size effect on their microstructure,phase transition and electrical *** ferroelectricity is demonstrated for the first time in 5 nm BT nanoceramics,while strong local piezoelectricity is present in 10 nm BSPT nanoceramics.

关键词： nanoceramic ferroelectric piezoelectric barium titanate size effe

含无机类富勒烯(IF)过渡族金属硫化物纳米复合涂层的环境摩擦磨损特性

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机械工程学报 2007年第1期43卷 77-82页

作者：涂江平浙江大学材料科学与工程系杭州310027

采用固—气相反应、反应沉淀和溶剂热诱导法实现了IF-MoS2、IF-WS2纳米粉体的宏观量制备。分别用化学共沉积方法在硬铝基体上制备Ni-P-(IF-WS2)复合镀层,磁控溅射和激光溅射技术在硬铝合金和钛合金基体上制备(Ni,Mo)/IF-(Mo,W)S2梯度纳... 详细信息

采用固—气相反应、反应沉淀和溶剂热诱导法实现了IF-MoS2、IF-WS2纳米粉体的宏观量制备。分别用化学共沉积方法在硬铝基体上制备Ni-P-(IF-WS2)复合镀层,磁控溅射和激光溅射技术在硬铝合金和钛合金基体上制备(Ni,Mo)/IF-(Mo,W)S2梯度纳米复合涂层和IF-(Mo,W)S2/(Ni,Mo)-IF-(Mo,W)S2多层纳米复合涂层。用划痕仪、球—盘式摩擦仪评估纳米涂层的结合力及其在真空(10-2pa)和大气中的摩擦磨损性能。Ni-P-(IF-MoS2)化学复合镀层的硬度、摩擦因数和磨损率明显低于Ni-P化学镀层。梯度和多层复合结构有利于涂层与合金基体结合力的提高。(Ni,Mo)/IF-(Mo,W)S2纳米梯度复合涂层和(Ni,Mo)-IF-(Mo,W)S2/IF-(Mo,W)S2纳米多层复合涂层在不同环境下都有低的摩擦因数和磨损率。含无机类富勒烯(IF-)WS2或MoS2的纳米复合涂层具有优良的环境稳定性。

关键词：无机类富勒烯结构 WS2 MoS2摩擦磨损纳米复合涂层环境

ANGPTL2 expression in gastric cancer tissues and cells and its biological behavior

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World Journal of Gastroenterology 2016年第47期22卷 10364-10370页

作者： Wei-Zhong Sheng Yu-Sheng Chen Chuan-Tao tu Juan He Bo Zhang Wei-Dong Gao Department of general surgery Fudan University affiliated zhongshan Hospital Department of Digestion Fudan University affiliated zhongshan Hospital

AIM To explore expression of angiopoietin-like protein 2(ANGpT L2) and its effect on biological behavior such as proliferation and invasiveness in gastric cancer. METHODS Western blotting was used to detect expression of ANGp TL2 in 60 human normal gastric tissues, 60 human gastric cancer tissues and gastric cell lines including GES-1, N87, SGC7901, BGC823 and pa MC82. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) and Transwell assay were used to detect the proliferation and invasive ability of gastric cancer cells. RESULTS Compared to normal tissues, ANGp TL2 protein levels were significantly upregulated in gastric tissues, and this level was closely correlated with gastric tumor grade, clinical stage and lymph node metastasis. Compared to GES-1 cells, ANGpT L2 mR NA and protein levels were significantly increased in gastric cancer cells including N87, SGC7901, BGC823 and p AMC82. The expression of ANGpT L2 in highly malignant gastric cancer cell lines BGC823 and pa MC82 was significantly higher than in low malignancy gastric cancer cell lines N87 and SGC7901. MTT and Transwell experiments indicated that the proliferation rate and invasive ability of stable overexpressed gastric cancer cells was faster than in cells transfected with Lv-NC and blank controlcells, and the invasive ability of stable overexpressed gastric cancer cells was higher than that of cells transfected with Lv-NC and blank control *** ANGp TL2 contributed to proliferation and invasion of gastric cancer cells. In clinical treatment, ANGpT L2 may become a new target for treatment of gastric cancer.

关键词： Gastric cancer Angiopoietin-like protein 2 Cell invasion Cell proliferation

Security-first architecture:deploying physically isolated active security processors for safeguarding the future of computing

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Cybersecurity 2018年第1期1卷 69-79页

作者： Dan Meng Rui Hou Gang Shi Bibo tu Aimin Yu Ziyuan Zhu Xiaoqi Jia Peng Liu Institute of Information Engineering Chinese Academy of SciencesBeijingChina Pennsylvania State University Old Main16801 State CollegePAUSA

It is fundamentally challenging to build a secure system atop the current computer *** complexity in software,hardware and ASIC manufacture has reached beyond the capability of existing verification *** whole-system verification,current systems have no proven *** is observed that current systems are exposed to a variety of attacks due to the existence of a large number of exploitable security *** vulnerabilities are difficult to remove without significant performance impact because performance and security can be conflicting with each *** worse,attacks are constantly evolving,and sophisticated attacks are now capable of systematically exploiting multiple vulnerabilities while remain hidden from *** to achieve security hardening of current computer architecture,existing defenses are mostly ad hoc and passive in *** are normally developed in responding to specific attacks spontaneously after specific vulnerabilities were *** a result,they are not yet systematic in protecting systems from existing attacks and likely defenseless in front of zero-day *** confront the aforementioned challenges,this paper proposes Security-first Architecture,a concept which enforces systematic and active defenses using Active Security *** systems built based on this concept,traditional processors(i.e.,Computation Processors)are monitored and protected by Active Security *** two types of processors execute on their own physically-isolated resources,including memory,disks,network and I/O *** Active Security Processors are provided with dedicated channels to access all the resources of the Computation Processors but not vice *** allows the Active Security Processors to actively detect and tackle malicious activities in the Computation Processors with minimum performance degradation while protecting themselves from the attacks launched from the Computation

关键词： hardware remove protected

Geological characteristics and the origin of ore-forming materials of(Laozhaiwan gold deposit, Yunnan Province

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矿床地质 2014年第S1期33卷 853-854页

作者： ZHAO DeKun CHEN CuiHua ZHANG Yan GU XueXiang tu ZongLin DAI HongZhang Sichuan Institute of Metallurgical Geology & Exploration College of Earth Science Chengdu University of Technology School of Earth Science and Resources China University of Geoscience

"Golden triangle"area bordered on Yunnan-Guizhou-Guangxi was one of the most important Carlin-type gold deposits concentration *** understanding of Carlin-type gold deposits in Guizhou and Guangxi Province had reached through several decades studies,but geological environment was very complex in the southeastern Yunnan,and Carlin-type gold deposits produced in the southeastern Yunnan were different from that of America,few studies were taken *** on a large number of field work,studies on the geological characteristics combining with geochemistry characteristics were taken,and analysis the genesis of Laozhaiwan gold *** types of alteration in Laozhaiwan gold deposit were mainly silicification and pyritization,and Gold grade was high when silicification and pyritization were both *** could be caculated that fluid density(g/cm3)varied from 0.7 to 4.9,salinity varied from 0.76%to 0.95%and ore-forming pressure(pa)varied from 1.81×105 to 49.96×105 according to fluid inclusion test results,showed that Laozhaiwan gold deposit was hypabyssal hydrothermal deposit in low temperature and low *** to composition of fluid inclusion analysis,combining with H-O isotope,made theδD-δ18O figure,showed that the fluid of the deposit rooted in formation water and mixed with meteoric waters later.

关键词： Geological characteristics and the origin of ore-forming materials of Laozhaiwan gold deposit Yunnan Province