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Electroless plating of copper layer on surfaces of urea-formaldehyde microcapsule particles containing paraffin for low infrared emissivity

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Particuology 2016年第1期14卷 159-163页

作者： xi Zhou jian Mao Zhen Qiao College of Materials Science and Engineering Sichuan University No. 24 South Section 1 Yihuan Road. Chengdu 610064 Sichuan China

A copper coating was deposited by electroless plating on the surfaces of urea-formaldehyde microcap- sules containing paraffin （UFP） particles. This composite microcapsule structure had low infrared OR） emissivity and maintained a constant temperature, and could be used in IR stealth applications. The eiectroless copper layer formation and its micro-appearance, and the effect of the copper layer on the IR emissivity and thermal properties of the composite microcapsules were investigated. The IR emissivity of the composite microcapsules at wavelengths of 1-14 μm gradually decreased with increasing copper mass on the surface. After formation of an integrated copper layer, the rate of IR emissivity decrease was lower. This is because the copper coating improves the surface conductivity of the UFP; a high conductivity results in high reflectivity, which leads to a decrease in IR emissivity. The lowest IR emissivity achieved was 0.68. The phase-change enthalpy of the composite microcapsules decreased with increasing amount of copper coated on the surface because of the high density of copper. When the mass increase of the UFP after electroless copper plating was about 300%, the composite microcapsules had low IR emissivity （about 0.8） and a high phase-change enthalpy （80J/g）.

关键词： Phase-change material Urea-formaldehyde microcapsules containing paraffin particle Electroless copper plating Low infrared emissivity Enthalpy

Learning curves of resection and reconstruction procedures in robotic-assisted pancreatoduodenectomy by a single surgeon:a retrospective cohort study of 160 consecutive cases

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Gastroenterology Report 2023年第1期11卷 424-432页

作者： xi-Tai Huang xi-Yu Wang jin-Zhao xie jian-Peng Cai Wei Chen Liu-Hua Chen xiao-Yu Yin Department of Pancreato-Biliary Surgery The First Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdongP.R.China

Background:Robotic-assisted pancreatoduodenectomy(RPD)has been routinely performed in a few of centers *** study aimed to evaluate the perioperative outcomes and the learning curves of resection and reconstruction procedures in RPD by one single ***:Consecutive patients undergoing RPD by a single surgeon at the First Affiliated Hospital of Sun Yat-sen University(Guangzhou,China)between July 2016 and October 2022 were *** perioperative outcomes and learning curves were retrospectively analysed by using cumulative sum(CUSUM)***:One-hundred and sixty patients were *** to the CUSUM curve,the times of resection and reconstruction procedures were shortened significantly after 30 cases(median,284 vs 195 min;P<0.001)and 45 cases(median,138 vs 120 min;P<0.001),*** estimated intraoperative blood loss(median,100 vs 50 mL;P<0.001)and the incidence of clinically relevant post-operative pancreatic fistula(29.2%vs 12.5%;P=0.035)decreased significantly after 20 and 120 cases,*** were no significant differences in the total number of lymph nodes examined,post-operative major complications,or post-operative length-of-stay between the two ***:Optimization of the resection procedure and the acquisition of visual feedback facilitated the performance of *** was a safe and feasible procedure in the selected patients.

关键词： robotic-assisted surgery pancreatoduodenectomy learning curve outcomes

Study on inelastic attenuation coefficient, site response and source parameters in Shanxi region

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Acta Seismologica Sinica(English Edition) 2004年第4期17卷 405-416页

作者： CHUO Yong-qing(啜永清) SU Yan(苏燕) JIA jian-xi(贾建喜) HUANG jin-gang (黄金刚) Earthquake Administration of Shanxi Province Taiyuan 030002 China Earthquake Administration of Shanxi Province Taiyuan 030002 China Earthquake Administration of Shanxi Province Taiyuan 030002 China Earthquake Administration of Shanxi Province Taiyuan 030002 China

Based on 310 horizontal-component digital seismograms recorded at 14 seismic stations in Shanxi Digital Seis-mograph Network, the inelastic attenuation coefficient in Shanxi region is studied. By the methods of Atkinson and Moya, the site response of each station and several source parameters are obtained and the inversion results from both methods are compared and analyzed. The frequency-dependent inelastic attenuation coefficient Q is estimated as Q( f )=323.2 f 0.506. The site responses of 14 seismic stations do not show significant amplification, which is consistent with their basement on rock. We also found the dependence of corner frequency on seismic moment, seismic moment on stress drop, source radius on stress drop.

关键词： Shanxi region Q value site response source parameter

Properties of DR1/PMMA-co-GMA for High Speed Electro-optical Switch

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Chemical Research in Chinese Universities 2012年第6期28卷 1091-1094页

作者： CAO Zi-jian jin Lin WANG xi-bin CUI Zhan-chen ZHANG Da-ming State Key Laboratory on Integrated Optoelectronics College of Electronic Science and Engineering State Key Laboratory of Superamolecular Structure and Materials Jilin University Changchun 130012 P. R. China

A non-linear optical（NLO） material was synthesized by means of a simple *** material can be applied in electro-optical（EO） devices,such as EO switches and *** Disperse Red 1（DR1） was doped in polymethyl-methacrylate-co-glycidyl methacrylate（PMMA-co-GMA） as the NLO active *** synthesis process and material structure were *** thermal properties,surface morphology and optical characteristics of the material were investigated by means of differential scanning calorimetry（DSC）,thermogravimetric analysis（TGA）,atomic force microscopy（AFM）,and m-lines *** the reflection technique,the value of the electro-optical coefficient γ 33 was measured as 11 pm/V at a wavelength of 1310 *** EO switch with nanosecond response based on this material has been fabricated.

关键词： Disperse Red 1/polymethyl-methacrylate-co-glycidyl methacrylate(DR1/PMMA-co-GMA) Electrooptical switch Thermal stability Optical property

Simulation and photoelectron track reconstruction of soft X-ray polarimeter

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Nuclear Science and Techniques 2021年第7期32卷 1-10页

作者： Xue-Feng Huang Hong-Bang Liu jin Zhang Bo Huang Wen-jin xie Huan-Bo Feng xi-Chen Cai xi-Wen Liu Zi-Li Li jian-Yu Gu Qian Liu jin Li En-Wei Liang Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China PLAC Key Laboratory of Quark and Lepton Physics(MOE)Central China Normal UniversityWuhan 430079China School of Physical Science University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

The soft X-ray polarimeter(SXP)is a detector with a wide energy range,large area,and large field of view.A SXP will be mounted on the Chinese Space Station and will mainly focus on detecting the polarization of transient soft X-ray(2–10 keV)sources,especially gamma-ray bursts(GRBs).In this work,a polarimeter detector unit is taken as an example,and Geant4 and Garfield++software are used to simulate the detection efficiency and track *** improved track reconstruction algorithm is proposed and used to reconstruct two-dimensional images of the *** this method,the initial emission angle of photoelectrons is reconstructed from the initial part of the track by shortening or extending the initial part of the track until the remaining track is straight,and the number of pixels is within an adjustable *** modulation factor of the photoelectronic tracks after reconstruction reaches approximately 57%in the photon energy range of 7–10 keV.

关键词： X-ray Polarimetry Track reconstruction algorithm

Synthesis and Characterization of a Novel Copoly(aryl ether ketone) Containing 4, 4'-Biphenyl-bis[4-phthalazin-1(2H)-one] Moiety

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Chinese Chemical Letters 2003年第2期14卷 145-146页

作者： Shao Yin ZHANG xi Gao jian Shu De xiAO jin Yan WANG Jie ZHANG Department of Polymer Science and Materials Dalian University of TechnologyDalian 116012

A new monomer of 4, 4-biphenyl-bis[4-phthalazin-1(2H)-one] was synthesized from biphenyl and phthalic anhydride, and a novel copoly(aryl ether ketone) (PPEK) was synthesized from 2, 2-bis(4-hydroxyphenyl)-propane (BPA), 4, 4'-biphenyl-bis-[4-phthalazin-1(2H)-one], 4, 4- difluorodiphenylketone (DFK). The monomer and copolymer were characterized by FT-IR and 1H-NMR. DSC and TGA were used to the novel polymer.

关键词： Poly(aryl ether ketone) 4,4'-biphenyl-bis[4-phthalazin-1(2H)-one] 2,2-bis(4-hydroxy- phenyl)-propane(BPA).

Evaluation of thermal effects on temperature-sensitive operating force of flow servo valve for fuel metering unit

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Chinese Journal of Aeronautics 2020年第6期33卷 1812-1823页

作者： Yang ZHANG Shaoping WANG jian SHI xi WANG School of Energy and Power Engineering Beihang UniversityBeijing 100083China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100083China

The temperature-induced variation in operating force of flow control valves may result in performance degradation or even jam faults of fuel metering unit(FMU), which significantly affects the safety of aircrafts. In this work, an analytical modeling approach of temperature-sensitive operating-force of servo valve is proposed to investigate the temperature characteristics in varying temperature conditions. Considering the temperature effects, a new extended model of flow force is built and an analytical model of valve friction is also derived theoretically based on the dynamic clearance induced by thermal effects. The extremum condition of friction is obtained to analyze the characteristic-temperature points where jam faults occur easily. The numerical results show that flow force increases firstly and then decreases as temperature increases under a constant valve opening. The maximum friction of flow servo valve can be uniquely determined when the structural parameters and ambient temperature are given. The worst situation just happens at the characteristic-temperature points, which are linearly related to the axial temperature gradients of valve spool. Such evaluations may give an explanation for the temperature-induced jam faults of vulnerable valves and provide a reference for designers to determine a suitable workingtemperature range of valves in practice.

关键词： Jam fault Servovalve Spool deformation Spool friction Temperature effect

Prediction of NO_(x)concentration using modular long short-term memory neural network for municipal solid waste incineration

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Chinese Journal of Chemical Engineering 2023年第4期56卷 46-57页

作者： Haoshan Duan xi Meng jian Tang Junfei Qiao Faculty of Information Technology Beijing University of TechnologyBeijing 100124China Beijing Laboratory of Smart Environmental Protection Beijing 100124China Beijing Key Laboratory of Computational Intelligence and Intelligent System Beijing 100124China Engineering Research Center of Intelligence Perception and Autonomous Control Ministry of Education Beijing 100124China

Air pollution control poses a major problem in the implementation of municipal solid waste incineration(MSWI).Accurate prediction of nitrogen oxides(NO_(x))concentration plays an important role in efficient NO_(x)emission *** this study,a modular long short-term memory(M-LSTM)network is developed to design an efficient prediction model for NO_(x)***,the fuzzy C means(FCM)algorithm is utilized to divide the task into several sub-tasks,aiming to realize the divide-and-conquer ability for complex ***,long short-term memory(LSTM)neural networks are applied to tackle corresponding sub-tasks,which can improve the prediction accuracy of the ***,a cooperative decision strategy is designed to guarantee the generalization performance during the testing or application ***,after being evaluated by a benchmark simulation,the proposed method is applied to a real MSWI *** the experimental results demonstrate the considerable prediction ability of the M-LSTM network.

关键词： Municipal solid waste incineration NO_(x)concentration prediction Modular neural network Model

Extended hopanes and 8,14-secohopanes up to C_(40)in unbiodegraded marine oils from the Tarim Basin,NW China

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Petroleum Science 2022年第2期19卷 498-508页

作者： jian-Ping Bao Cui-Shan Zhu xi Yang Hubei Key Laboratory of Petroleum Geochemistry and Environment Key Lab.of Exploration Technologies for Oil&Gas ResourcesMinistry of EducationGeochemistry DepartmentYangtze UniversityWuhan430100HubeiChina

Extended 17α(H),21β(H)-hopanes and three series of 8,14-secohopanes up to C_(40),including 8α(H),14α(H),17α(H),21β(H)-,8α(H),14α(H),17β(H),21α(H)-and 8α(H),14β(H),17β(H),21α(H)-,were detected by GC-MS-MS method in the branched/cyclic hydrocarbon fractions of some unbiodegraded marine oils from the Tazhong uplift in the Tarim Basin,NW *** coexistence of extended hopanes and 8,14-secohopanes up to C_(40)in unbiodegraded oils suggests that they are primary and independent on *** similarity of distribution and composition for extended hopanes and 8,14-secohopanes up to C_(40)in unbiodegraded oils proposes that they could be derived from a similar biological ***,an abrupt decrease up to 3-5 times in the relative abundance from C_(35)to C_(36)in C_(31-40)extended hopanes and extended 8,14-secohopanes suggests that C_(31-35)and C_(36-40)extended hopanes and extended 8,14-secohopanes should have their own biological *** known C35bacteriohopanetetrol should be biological precursor of C_(31-35)extended hopanes and 8,14-secohopanes,but an unknown C_(40)functionalized hopanoid could be biological precursor of C_(36-40)extended hopanes and 8,*** attention should be paid to their potential roles in oil-source correlation for severely biodegraded oils based on their widespread occurrence in various source rocks,unbiodegraded and severely biodegraded oils.

关键词： Extended hopanes Extended 8,14-secohopanes Biomarkers Bacteriohopanetetrol Unbiodegraded marine oils Tazhong Uplift Tarim Basin