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A new type of lipophilic hydrophobic self-repairing cellulose insulating paper developed with ST-110/FAS/PTFE ternary system as coating substrate

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High Voltage 2024年第2期9卷 474-483页

作者： Zhenglin Zeng Jinshan Qin Zuhao Wang weimin Tan chao Tang College of Engineering and Technology Southwest UniversityChongqingChina International R&D Center for New Technologies of Smart Grid and Equipment ChongqingChina

The moisture generated by the ageing of the oil-paper insulating system can easily lead to the deterioration of the performance of the insulating *** order to alleviate the impact of moisture on the performance of the insulating paper,we developed a kind of lipophilic hydrophobic self-repairing cellulose insulating paper(new insulating paper)based on the ternary system of polytetrafluoroethylene,fluorocarbon surfactant and fluorinated alkyl silane,and accelerated thermal ageing test for 45 days at 130°C was carried *** experimental results show that the new insulating paper with excellent lipophilic property can realise hydrophobic self-repairing through heat treatment after physical *** tensile strength and elongation at break of the new insulating paper increased by 5%–8%and 6.25%–27%respectively compared with the original cellulose insulating *** the end of ageing,the relative dielectric constant and dielectric loss factor of new insulating paper are 10.4%and 9.9%lower than that of the original cel-lulose insulating paper,while the breakdown voltage is 6.8%*** acid and moisture content produced during the ageing process of the insulating oil impregnated with new insulating paper are also less,indicating that the coating can delay the ageing of the insulating paper.

关键词： coating moisture cellulose

Numerical and experimental investigation of aerodynamic heat control of leading edge of hypersonic vehicle's flexible skin

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Science China(Information Sciences) 2022年第10期65卷 211-224页

作者： Xiaozhou Lü chao YUAN weimin BAO Guanghui BAI Fancheng MENG School of Aerospace Science and Technology Xidian University Science and Technology on Space Physics Laboratory College of Materials Science and Engineering Chongqing University of Technology

In this paper, a flexible skin inspired by the sudoriferous gland structure of human skin is developed for ultra-thermal protection of hypersonic morphing vehicles. The effect of different coolants and cooling flow rates on the cooling performance of the leading edge is studied using finite element analysis.A wind tunnel experiment is conducted at high temperatures with the heat flux Q = 700 k W/m2, and the results indicate the following:(1) the flexible skin can effectively reduce the surface temperature of hypersonic vehicles;(2) when using liquid water instead of argon as the cooling medium, the cooling efficiency of flexible skin performs better;(3) when liquid water is used as the cooling medium, the cooling effect peaks at a flow rate of 0.01 m/s, and further increasing the flow rate will not benefit cooling efficiency significantly;(4) the flexible skin can withstand extreme thermal environments, demonstrating its feasibility in applications of over-limit thermal protection for hypersonic morphing vehicles. This study aims at optimizing the cooling performance of the flexible skin for ultra-thermal protection. The proposed skin can overcome the heat-resistance limit of flexible materials with morphing properties, laying a theoretical and experimental foundation for its future applications in hypersonic morphing vehicles.

关键词： hypersonic vehicle flexible skin ultra-thermal protection micro-channel transpiration cooling

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高通量低成本检测牛MSTN基因突变的DAVID技术构建

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农业生物技术学报 2025年第1期33卷 208-219页

作者：裴栋超海超赵春生张立果吴迪王德政张鑫怡杨磊李光鹏内蒙古大学省部共建草原家畜生殖调控与繁育国家重点实验室

肌肉生长抑制素(myostatin, MSTN)是骨骼肌生长发育的负调控因子，MSTN基因突变可促进动物肌肉发育。目前Sanger测序是检测MSTN基因突变的经典方法，但此方法存在检测通量低、可视化程度低和检测费用高等缺点。本研究利用二代测序技术... 详细信息

肌肉生长抑制素(myostatin, MSTN)是骨骼肌生长发育的负调控因子，MSTN基因突变可促进动物肌肉发育。目前Sanger测序是检测MSTN基因突变的经典方法，但此方法存在检测通量低、可视化程度低和检测费用高等缺点。本研究利用二代测序技术，通过设计的特异性Barcode序列，能够一次性检测96头牛(Bos taurus)的MSTN基因突变情况。此外，根据测序Fastq结果文件中的Barcode序列，利用异步线程和并发算法，编写了相关的数据分析DAVID(detect and visualize insertion-deletion)软件。利用DAVID软件将96个混合样本的测序数据逐一拆分，并与扩增子序列(amplicon sequence)比对，最终获得MSTN基因突变的图形和统计信息。利用DAVID技术对96头蒙古牛进行检测，结果发现1头牛的MSTN基因11 bp杂合缺失，剩余95头均为野生型，并且通过Sanger测序对11 bp杂合缺失进行了验证。综上，本研究构建了一个检测牛MSTN基因突变的高通量技术体系，为肉牛遗传改良和育种提供技术支撑。

关键词：肌肉生长抑制素(MSTN) 蒙古牛基因突变基因型检测

Metallogenesis and major challenges of porphyry copper systems above subduction zones

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Science China Earth Sciences 2020年第7期63卷 899-918页

作者： Huayong CHEN chao wu Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of Sciences

Porphyry copper±molybdenum±gold deposits(PCDs) are the most representative magmatic-hydrothermal metallogenic system above subduction zones with important economic value. Previous studies revealed that large PCDs are generally formed from initial arc magmas(from subduction-induced partial melting of the mantle wedge), which eventually ascend to the shallow crust(3–5 km) for mineralization after a series of complex evolution processes. These processes include(1) the dehydration or partial melting of subducting slab, which induces partial melting of the metasomatized mantle wedge;(2)the ascent of mantle-derived magma to the bottom of the lower crust, which subsequently undergoes crustal processes such as assimilation plus fractional crystallization(AFC) or melting, assimilation, storage and homogenization(MASH);(3) the magma chamber formation at the bottom of the lower, middle and upper crust;(4) the final emplacement and volatilization of porphyry stocks;and(5) the accumulation of ore-forming fluids and metal precipitation. Despite the many decades of research, many issues involving the PCD metallogenic mechanism still remain to resolve, such as(1) the tectonic control on the geochemical characteristics of ore-forming magma;(2) the reason for the different lifespans of the long-term magmatic arc evolution and geologically "instantaneous" mineralization processes;(3) the source of ore-forming materials;(4) the relative contributions of metal pre-enrichment to mineralization by the magma source and by magmatic evolution;and(5) the decoupling behaviors of Cu and Au during the pre-enrichment. These issues point out the direction for future PCD metallogenic research, and the resolution to them will deepen our understanding of the metallogenesis at convergent plate boundaries.

关键词： Subduction zone Porphyry Cu deposit Metallogenesis

Kinematics,Deformation,and Aerodynamics of a Flexible Flapping Rotary Wing in Hovering Flight

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Journal of Bionic Engineering 2021年第1期18卷 197-209页

作者： chao Zhou Jianghao wu School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China School of Transportation Science and Engineering Beihang UniversityBeijing 100191China

The Flapping Rotary Wing(FRW)is a micro air vehicle wing layout coupling flapping,pitching,and rotating *** can gain bencfits in high lift from a fast passive rotating motion,which is tightly related to the passive pitching motion directly caused by wing flexible ***,flexible deformation is crucial for the wing kinematics and aerodynamic performance of an *** this paper,we explored the effct of flexibility on wing kinematics and acrodynamics on the basis of a mechanical FRW model.A photogrammetric method was adopted to capture motion images according to which wing orientations and deformations were *** acrodynamic force was computed using computational fluid dynamic method,and wing kinematics and deformations were used as simulation *** experimental measurements presented the real orientation and deformation pattem of a real *** wing passive deformation of a high-intensity FRW was found to be mainly caused by inertial force,and a linear positive spanwise twist was observed in the *** effects of wing deformation on aerodynamic force production and the underlying mechanism were *** showed that lift augment,rotating moment enhancement,and power efficiency improvement can be achieved when a wing becomes *** spanwise twist mainly accounts for these changes in aerodynamics,and increment in spanwise twist could further contributes to aerodynamic improvement.

关键词： bionic robot micro air vehicle flapping wing flexibility unsteady aerodynamic twist deformation

Influence of the characteristics of fault gouge on the stability of a borehole wall

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Journal of Mountain Science 2016年第5期13卷 930-938页

作者： WANG sheng CHEN Li-yi HUANG Run-qiu LI Zhi-jun wu Jin-sheng YUAN chao-peng State Key Laboratory of Geohazard Prevention&Geoenvironment Protection Chengdu University of TechnologyChengdu Siehuan 610059China The Institute of Exploration Technology of CAGS Chengdu 611734China

How to find more effective way to stabilize the borehole wall in the fault gouge section is the key technical challenge to control the stability of the borehole wall in the Wenchuan fault gouge section during the process of core drilling. Here we try to describe the characters of deep fault gouge in fracture zones from the undisturbed fault gouge samples which are obtained during the core drilling. The X- Ray Diffraction （XRD）, X-Ray Fluorescence （XRF） and Scanning Electron Microscope （SEM） provided the detailed information of the fault gouge＇s microscopic characteristics on the density, moisture content, expansibility, dispersity, permeability, tensile strength and other main physical-mechanical properties. Based on these systematic experimental studies above and analysis of the fault gouge instability mechanism, a new technical procedure to stabilize the borehole wall is proposed -- a low water and a low loss low permeability drilling fluid system that consists of 4% day ＋ 0.5% CMC-HV ＋ 2% S-1 ＋ 3%sulfonated asphalt ＋ 1% SMC ＋ 0.5% X-1 ＋ 0-5% T type lubricant ＋ barite for core drilling in fault gouge sections.

关键词： Fault gouge Microscopic characteristics Borehole wall stability Drilling fluid

Characteristics and failure mechanism of an ancient earthquake-induced landslide with an extremely wide distribution area

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Journal of Mountain Science 2018年第2期15卷 380-393页

作者： HUANG chao LI Yu-sheng YI Shu-jian LIU Kai wu Chun-hao State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China Key Laboratory of Mountain Hazards and Surface Process Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610044 China University of Chinese Academy of Science Beijing 100049 China

The Lamuajue landslide is located in Lamuajue village on the tight bank of the Meigu River, Sichuan Province, China. This landslide is an ancient landslide with an extremely wide distribution area, covering an area of 19 km2 with a maximum width of 5-5 km and an estimated residual volume of 3 × 108 ma. The objectives of this study were to identify the characteristics and failure mechanism of this landslide. In this study, based on field investigations, aerial photography, and profile surveys, the boundary, lithology, structure of the strata, and characteristics of the landslide deposits were determined. A gently angled weak interlayer consisting of shale was the main factor contributing to the occurrence of the Lamuajue landslide. The deposition area can be divided into three zones： zone A is an avalanche deposition area mainly composed of blocks, fragments, and debris with diameters ranging from o.i m to 3 m; zone B is a residual integrated rock mass deposition area with large blocks, boulders and ＂fake bedrock＂; and zone C is a deposition zone of limestone blocks and fragments. Three types of failure mechanism were analyzed and combined to explain the Lamuajue landslide based on the features of the accumulation area. First, a shattering-sliding mechanism caused by earthquakes in zone A. Second, a sliding mechanism along the weak intercalation caused by gravity and water in zone B. Third, a shattering-ejection mechanism generated by earthquakes in zone C. The results provide a distinctive case for the study of gigantic landslides induced by earthquakes, which is very important for understanding and assessing ancient earthquakeinduced landslides.

关键词： Earthquake-induced landslide Lamuajue landslide Ancient landslide Geologicalfeature Failure mechanism

Systemic treatment for severe concentrated sulfuric acid burns in an adult male at high altitude:A case report

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World Journal of Clinical Cases 2020年第7期8卷 1337-1342页

作者： Ruo-Mei Zhao Yi Li sheng-wu chao Hong-Jin Wang The Graduate School Of Qinghai University Xining 810016Qinghai ProvinceChina Department of Burns and plastic Surgery Qinghai University Affiliated Hospital of Qinghai UniversityXining 810016Qinghai ProvinceChina

BACKGROUND The aim of this study was to report a case of a patient who suffered from severe concentrated sulfuric acid burns while working at high *** patient recovered after systemic *** also provide a literature review for a better understanding of the *** SUMMARY A 30-year-old male,who was working in a local chemical plant in Xining at an altitude of 2261 m,suffered from 85%burns(Ⅲ°70%,deep Ⅱ°15%)after a tank containing 80%concentration of sulfuric acid *** patient immediately received a series of first aid treatments,as well as rigorous wound managements after admission,which included protection for the whole body and organs,prevention and treatment of eye burns,and the appropriate oxygen *** 65 d of treatment,the burn wounds had completely healed,and the patient was transferred to another specialized hospital for further eye *** first aid before admission and the emergency treatment of wounds following admission were *** severe complications of sepsis,severe renal insufficiency,septic costal chondritis,corneal perforation or other burns occurred during the *** The main causes of concentrated sulfuric acid burns consisted of accidental burns at work,accidents in the outside,factitious injuries and improper laboratory *** clinical manifestations were mostly deep Ⅱ°and Ⅲ°burns,with a formation of brown-black,leather-like eschar on the wound surface and locally embolized dendrite-like *** clear cause of the injury and typical clinical manifestations in this case made it easy to ***,adult cases with severe concentrated sulfuric acid burns in high altitude areas are rare,so the successful treatment of this case is of great significance.

关键词： High altitude area Concentrated sulfuric acid burns Extensive burn Case report

5G Wideband Bandpass Filtering Power Amplifiers Based on a Bandwidth-Extended Bandpass Matching Network

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China Communications 2023年第11期20卷 56-66页

作者： weimin Wang Hongmin Zhao Yongle wu Xiaopan Chen School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China School of Integrated Circuits Beijing University of Posts and TelecommunicationsBeijing 100876China

In this paper,a 5G wideband power amplifier(PA)with bandpass filtering response is synthesized using a bandwidth-extended bandpass filter as the matching network(MN).In this structure,the bandwidth(θ_(C))is defined as a variable in the closedform equations provided by the microstrip bandpass *** can be extended over a wide range only by changing the characteristic impedances of the *** from the other wideband MNs,the extension of bandwidth does not increase the complexity of the structure(order n is fixed).In addition,based on the bandwidth-extended structure,the wideband design of bandpass filtering PA is not limited to the fixed bandwidth of the specific filter *** theoretical analysis of the MN and the design flow of the PA are provided in this *** fabricated bandpass filtering PA can support almost one-octave bandwidth(2-3.8 GHz),covering the two 5G bands(n41 and n78).The drain efficiency of 47%-60%and output power higher than 40 dBm are *** frequency selectivity in S-parameter measurements can be observed.

关键词： bandpass filtering bandwidth-extension fixed order power amplifier wideband