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Science China Materials 2024年第3期67卷 1009-1010页

作者： yan zhu School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210093China

Generating high-value chemical compounds by catalytically converting carbon resources—typically derived from coal and biomass, etc.—is crucial. It is more meaningful to achieve“carbon neutrality” and lower production costs by utilizing industrial waste carbon sources, such as steel mill waste gases,which are typically intended for direct emission or burning into CO_(2).

关键词： typically utilizing meaningful

Performance improvement of licklider transmission protocol in complex deep space networks based on parameter optimization

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Chinese Journal of Aeronautics 2023年第5期36卷 406-420页

作者： Guo YU Zhenxing DONG yan zhu Key Laboratory of Electronics and Information Technology for Space Systems National Space Science CenterChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

A reasonable parameter configuration helps improve the data transmission performance of the Licklider Transmission Protocol(LTP).Previous research has focused mainly on parameter optimization for LTP in simplified scenarios with one to two hops or multihop scenarios with a custody mechanism of the Bundle Protocol(BP).However,the research results are not applicable to communications in Complex Deep Space Networks(CDSNs)without the custody mechanism of BP that are more suitable for deep space communications with *** this paper,we propose a model of file delivery time for LTP in *** on the model,we propose a Parameter Optimization Design Algorithm for LTP(LTP-PODA)of configuring reasonable parameters for *** results show that the accuracy of the proposed model is at least 6.47%higher than that of the previously established models based on simple scenarios,and the proposed model is more suitable for ***,the LTP parameters are optimized by the LTP-PODA algorithm to obtain an optimization *** the optimization plan for LTP improves the protocol transmission performance by at least 18.77%compared with configuring the other parameter configuration plans.

关键词： Complex deep space networks File delivery time model Licklider Transmission Protocol(LTP) Network Performance Network Protocols Parameter optimization Performance improvement

Analysis of sliding electric contact characteristics in augmented railgun based on the combination of contact resistance and sliding friction coefficient

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Defence Technology（防务技术） 2020年第4期16卷 747-752页

作者： Chun-yan zhu Bao-ming Li National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyChina

The contact resistance between the armature and rails is an important indicator of the contact characteristics in electromagnetic *** the contact resistance depends not only on the contact state but also on the contact stress and temperature,there are some limitations in analyzing the contact characteristics using only the contact *** this paper,the contact characteristics of the augmented railgun are analyzed by the combination of contact resistance and sliding friction ***,the theoretical calculation model of the contact resistance and friction coefficient of the augmented electromagnetic railgun is *** the contact resistance and friction coefficient are calculated by the measured values of the muzzle voltage,rail current and armature ***,the contact characteristics are analyzed according to the features of the waveforms of the contact resistance and the friction coefficient,and the analysis conclusions are verified by experimental rail *** results showed that:the aluminum melt film gradually formed on the contact surface reduces the contact resistance and the friction coefficient;the wear and erosion of the armature cause deterioration of the contact state;after the transition,the reliability of the sliding contact between the armature and rails decreases,resulting in an increase in contact resistance.

关键词： Augmented railgun Contact resistance Friction coefficient Contact characteristics

High-order Soliton Matrix for the Third-order Flow Equation of the Gerdjikov-Ivanov Hierarchy Through the Riemann-Hilbert Method

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 358-378页

作者： Jin-yan zhu Yong CHEN School of Mathematical Sciences Shanghai Key Laboratory of Pure Mathematics and Mathematical PracticeEast China Normal UniversityShanghai 200062China College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

The Gerdjikov-Ivanov(GI)hierarchy is derived via recursion operator,in this article,we mainly investigate the third-order flow GI *** the framework of the Riemann-Hilbert method,the soliton matrices of the third-order flow GI equation with simple zeros and elementary high-order zeros of Riemann-Hilbert problem are constructed through the standard dressing *** advantage of this result,some properties and asymptotic analysis of single soliton solution and two soliton solution are discussed,and the simple elastic interaction of two soliton are *** with soliton solution of the classical second-order flow,we find that the higher-order dispersion term affects the propagation velocity,propagation direction and amplitude of the ***,by means of a certain limit technique,the high-order soliton solution matrix for the third-order flow GI equation is derived.

关键词： Gerdjikov-Ivanov hierarchy third-order flow GI equation Riemann-Hilbert method high-order soliton

Microstructure and Martensitic Transformation Behaviors of Explosively Welded NiTi/NiTi Laminates

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Chinese Journal of Aeronautics 2007年第2期20卷 168-171页

作者： yan zhu CUI Li-shan ZHENG yan-jun Department of Materials Science and Engineering China University of Petroleum Beijing 102249 China

The study is a first attempt to prepare bulk NiTi/NiTi shape memory alloy （SMA） laminates with a macroscopic heterogeneous composition by explosive welding and investigate their microstructures and martensitic transformation behaviors. After explosive weld- ing, a perfect interfacial bonding between the two components and a reversible martensitic transformation are realized in the tandem. Results show achievement of a fine granular structure and the maximum value of microhardness near the welding interface because of the excessive cold plastic deformation and the high impact velocity during the explosive welding. Meanwhile, the effects of aging on the transformation of the welded tandem are investigated by differential scanning calorimeter （DSC） and subject to discussion. The trans- formation temperatures of NiTi/NiTi SMAs increase with the rise of the aging temperature. The experimental results indicate the shape memory properties of NiTi/NiTi SMA fabricated by explosive welding can be improved by optimizing the aging technology.

关键词： NiTi shape memory alloy explosive welding martensitic transformation

USP19 Stabilizes TAK1 to Regulate High Glucose/Free Fatty Acid-induced Dysfunction in HK-2 Cells

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Current Medical Science 2024年第4期44卷 707-717页

作者： Xiao-hui yan Yin-na zhu yan-ting zhu Kidney Disease and Dialysis Center Shaanxi Provincial People's HospitalXi'an 710068China Department of Nephrology The Third Affiliated Hospital of Xi'an Medical UniversityXi'an 710000China Nephrology and Hemodialysis Center Shaanxi Provincial People's HospitalXi'an 710068China

Objective Obesity-induced kidney injury contributes to the development of diabetic nephropathy(DN).Here,we identified the functions of ubiquitin-specific peptidase 19(USP19)in HK-2 cells exposed to a combination of high glucose(HG)and free fatty acid(FFA)and determined its association with TGF-beta-activated kinase 1(TAK1).Methods HK-2 cells were exposed to a combination of HG and ***19 mRNA expression was detected by quantitative RT-PCR(qRT-PCR),and protein analysis was performed by immunoblotting(IB).Cell growth was assessed by Cell Counting Kit-8(CCK-8)viability and 5-ethynyl-2′-deoxyuridine(EdU)proliferation *** cycle distribution and apoptosis were detected by flow *** USP19/TAK1 interaction and ubiquitinated TAK1 levels were assayed by coimmunoprecipitation(Co-IP)assays and *** In HG+FFA-challenged HK-2 cells,USP19 was highly ***19 knockdown attenuated HG+FFA-triggered growth inhibition and apoptosis promotion in HK-2 ***,USP19 knockdown alleviated HG+FFA-mediated PTEN-induced putative kinase 1(PINK1)/Parkin pathway inactivation and increased mitochondrial reactive oxygen species(ROS)generation in HK-2 ***,USP19 stabilized the TAK1 protein through ***,increased TAK1 expression reversed the USP19 knockdown-mediated phenotypic changes and PINK1/Parkin pathway activation in HG+FFA-challenged HK-2 *** The findings revealed that USP19 plays a crucial role in promoting HK-2 cell dysfunction induced by combined stimulation with HG and FFAs by stabilizing TAK1,providing a potential therapeutic strategy for combating DN.

关键词： HK-2 cells high glucose free fatty acid dysfunction USP19 deubiquitination

Biochemical characterization of chitin synthase activity and inhibition in the African malaria mosquito, Anopheles gambiae

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Insect Science 2013年第2期20卷 158-166页

作者： Xin Zhang Kun yan zhu Department of Entomology Kansas State University Manhattan KS 66506 USA

Chitin synthase （CHS） is an important enzyme catalyzing the formation of chitin polymers in all chitin containing organisms and a potential target site for insect pest control. However, our understanding of biochemical properties of insect CHSs has been very limited. We here report enzymatic and inhibitory properties of CHS prepared from the African malaria mosquito, Anopheles gambiae. Our study, which represents the first time to use a nonradioactive method to assay CHS activity in an insect species, determined the optimal conditions for measuring the enzyme activity, including pH, temperature, and concentrations of the substrate uridine diphosphate N-acetyl-D-glucosamine （UDP- GlcNAc） and Mg＋＋. The optimal pH was about 6.5-7.0, and the highest activity was detected at temperatures between 37℃ and 44℃. Dithithreitol is required to prevent melanization of the enzyme extract. CHS activity was enhanced at low concentration of GIcNAc, but inhibited at high concentrations. Proteolytic activation of the activity is significant both in the 500×g supernatant and the 40 000×g pellet. Our study revealed only slight in vitro inhibition ofA. gambiae CHS activity by diflubenzuron and nikkomycin Z at the highest concentration （2.5μmol/L） examined. There was no in vitro inhibition by polyoxin D at any concentration examined. Furthermore, we did not observe any in vivo inhibition of CHS activity by any of these chemicals at any concentration examined. Our results suggest that the inhibition of chitin synthesis by these chemicals is not due to direct inhibition of CHS in A. gambiae.

关键词： Anophele gambiae chitin synthase diflubenzuron enzyme inhibition

Operation of a Rotary-valved Pulse Detonation Rocket Engine Utilizing Liquid-kerosene and Oxygen

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Chinese Journal of Aeronautics 2011年第6期24卷 726-733页

作者： WANG Ke FAN Wei yan Yu zhu Xudong yan Chuanjun School of Power and Energy Northwestern Polytechnical University Xi ＇an 710072 China

The pulse detonation rocket engine （PDRE） requires periodic supply of oxidizer, fuel and purge gas. A rotary-valve assembly is fabricated to control the periodic supply in this research. Oxygen and liquid aviation kerosene are used as oxidizer and fuel respectively. An ordinary automobile spark plug, with ignition energy as low as 50 mJ, is used to initiate combustion. Steady operation of the PDRE is achieved with operating frequency ranging from 1 Hz to 10 Hz. Experimentally measured pressure is lower than theoretical value by 13% at 1 Hz and 37% at 10 Hz, and there also exists a velocity deficit at different operating frequencies. Both of these two phenomena are believed mainly due to droplet size which depends on atomization and vaporiza-tion of liquid fuel.

关键词： pulse detonation rocket engines rotary-valve velocity deficit kerosene oxygen

Electrocatalytic response of poly(cobalt tetraaminophthalocyanine)/multi-walled carbon nanotubes-Nafion modified electrode toward sulfadiazine in urine

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第6期13卷 503-510页

作者： Xiao-ping HONG yan zhu yan-zhen ZHANG Department of Chemistry Zhejiang UniversityHangzhou 310028China Department of Chemistry Zhejiang Sci-Tech UniversityHangzhou 310018China Department of Stomatology the Second Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310009China

A highly sensitive amperometric sulfadiazine sensor fabricated by electrochemical deposition of poly(cobalt tetraaminophthalocyanine) (poly(Co II TAPc)) on the surface of a multi-walled carbon nanotubes-Nafion (MWCNTs-Nafion) modified electrode is *** electrode showed a very attractive performance by combining the advantages of Co II TAPc,MWCNTs,and *** with the bare glassy carbon electrode (GCE) and the MWCNTs-Nafion modified electrode,the electrocatalytic activity of poly(Co II TAPc)-coated MWCNTs-Nafion GCE generated greatly improved electrochemical detections toward sulfadiazine including low oxidation potential,high current responses,and good anti-fouling *** oxidation peak currents of sulfadiazine obtained on the new modified electrode increased linearly while increasing the concentration of sulfadiazine from 0.5 to 43.5 μmol/L with the detection limit of 0.17 μmol/L.

关键词： Sulfadiazine Electrochemical detection Cobalt tetraaminophthalocyanine Multi-walled carbon nanotubes

Network Evaluation and Protocol Deployment for Complex Deep-Space Networks Based on DTN

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China Communications 2020年第9期17卷 237-258页

作者： Guo Yu Zhenxing Dong yan zhu Key Laboratory of Electronics and Information Technology for Space Systems National Space Science CenterChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Previous research on deep-space networks based on delay-tolerant networking(DTN)has mainly focused on the performance of DTN protocols in simple networks;hence,research on complex networks is *** this paper,we focus on network evaluation and protocol deployment for complex DTNbased deep-space networks and apply the results to a novel complex deep-space network based on the Universal Interplanetary Communication Network(UNICON-CDSN)proposed by the National Space Science Center(NSSC)for simulation and verification.A network evaluation method based on network capacity and memory analysis is *** on a performance comparison between the Licklider Transmission Protocol(LTP)and the Transmission Control Protocol(TCP)with the Bundle Protocol(BP)in various communication scenarios,a transport protocol configuration proposal is developed and used to construct an LTP deployment scheme for *** the LTP deployment scheme,a theoretical model of file delivery time over complex deep-space networks is built.A network evaluation with the method proposed in this paper proves that UNICONCDSN satisfies the requirements for the 2020 Mars exploration mission ***,simulation results from a universal space communication network testbed(USCNT)designed by us show that the LTP deployment scheme is suitable for UNICON-CDSN.

关键词： complex deep-space network network capacity memory analysis protocol deployment testbed