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Petroleum Science 2022年第4期19卷 1473-1482页

作者： Peng-Fei Lv Yu Liu Feng Liu wen-zhe yang Han-Tao Liu Bo Zhang Yong-Chen Song School of Energy and Power Engineering North University of ChinaTaiyuanShanxi030051China Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education Dalian University of TechnologyDalianLiaoning116024China Tianjin Refrigeration Technology Key Laboratory Tianjin University of CommerceTianjin300134China School of Chemical and Biological Engineering Taiyuan University of Science and TechnologyTaiyuanShanxi030024China

The phenomenon of multiphase flow in porous media is confronted in various fields of science and industrial applications. Owing to the complicated porous structure, the flow mechanisms are still not completely resolved. A critical and fundamental question is the variation of pore structure and REV sizes among different types of porous media. In this study, a total of 22 porous samples were employed to systematically evaluate the pore-based architecture and REV sizes based on X-ray CT image analysis and pore network modelling. It is found that the irregular grain shapes give rise to large specific areas,narrow and thin throats in identical sand packs. The packs with more types of sands, or composited by the sands with larger difference in diameter, have larger specific area, smaller tortuosity and pore *** on the REV measurement through porosity solely, the REV sizes of sand packs are generally in the order of magnitude of 10^(-2) m L, while it is at least one order of magnitude smaller in rock cores. Our result indicates that the combination of porosity and Euler number is an effective indicator to get the REV sizes of porous samples.

关键词： Pore structure REV Sand pack Rock core Pore network modelling

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振动条件下平行孔板间流体的作用力实验

原子能科学技术 2017年第8期51卷 1419-1424页

作者：刘雨陆道纲王园鹏李文哲李宗洋华北电力大学核科学与工程学院北京102206 华北电力大学非能动核能安全技术北京市重点实验室北京102206

乏燃料贮存格架自由放置在乏燃料水池内,格架-格架、格架-池壁之间有一定间隙。在地震载荷下,这些间隙中流体的流固耦合作用耗散了结构的能量,保证了格架的结构完整性。根据AP1000和CAP1400系列反应堆型的格架储存腔设计,格架的侧壁有... 详细信息

乏燃料贮存格架自由放置在乏燃料水池内,格架-格架、格架-池壁之间有一定间隙。在地震载荷下,这些间隙中流体的流固耦合作用耗散了结构的能量,保证了格架的结构完整性。根据AP1000和CAP1400系列反应堆型的格架储存腔设计,格架的侧壁有平板或孔板两种方案。对格架进行结构动力学分析时,为了简化流体间隙附加质量的计算,工程上一般将孔板直接简化为平板。这样的方法并不能精确反映出实际的流固耦合效应。为获得格架与格架、格架与池壁间流体的流固耦合特性,搭建实验台架,通过振动实验,测量孔板的间隙流体在不同激振频率、不同间隙条件下的流体作用力。实验最终给出孔板的间隙流体的流体力,并给出了不同间隙条件下附加质量,本文可为AP1000和CAP1400系列乏燃料储存格架的流固耦合参数选取提供依据。

关键词：乏燃料贮存格架间隙流体流固耦合附加质量振动实验孔板

Effects of Bifidobacterium lactis BLa80 on fecal and mucosal flora and stem cell factor/c-kit signaling pathway in simulated microgravity rats

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World Journal of Gastroenterology 2025年第1期31卷 93-109页

作者： Ping Zhang Ying Zhu Pu Chen Tong Zhou zhe-Yi Han Jun Xiao Jian-Feng Ma wen Ma Peng Zang Ying Chen Graduate School Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina Key Laboratory of Aerospace Nutrition and Food Engineering China Astronaut Research and Training CenterBeijing 100094China Department of Gastroenterology The Air Force Medical CenterBeijing 100142China Department of Blood Transfusion Air Force Medical CenterBeijing 100142China

BACKGROUND Simulated microgravity environment can lead to gastrointestinal motility *** pathogenesis of gastrointestinal motility disorders is closely related to the stem cell factor(SCF)/c-kit signaling pathway associated with intestinal flora and Cajal stromal ***,intestinal flora can also affect the regulation of SCF/c-kit signaling pathway,thus affecting the expression of Cajal stromal *** cells are the pacemakers of gastrointestinal *** To investigate the effects of Bifidobacterium lactis(***)BLa80 on the intestinal flora of rats in simulated microgravity and on the gastrointestinal motility-related SCF/c-kit *** The internationally recognized tail suspension animal model was used to simulate the microgravity environment,and 30 rats were randomly divided into control group,tail suspension group and drug administration tail suspension group with 10 rats in each group for a total of 28 *** tail group was given *** BLa80 by intragastric administration,and the other two groups were given water intragastric administration,the concentration of intragastric administration was 0.1 g/mL,and each rat was 1 mL/***&eosin staining was used to observe the histopathological changes in each segment of the intestine of each group,and the expression levels of SCF,c-kit,extracellular signal-regulated kinase(ERK)and p-ERK in the gastric antrum of each group were detected by Western blotting and *** fecal flora and mucosal flora of rats in each group were detected by 16S *** Simulated microgravity resulted in severe exfoliation of villi of duodenum,jejunum and ileum in rats,marked damage,increased space between villi,loose arrangement,shortened columnar epithelium of colon,less folds,narrower mucosal thickness,reduced goblet cell number and crypts,and significant improvement after probiotic *** microgravity reduced the expressions of SCF and c-kit,and increased the express

关键词： Simulated microgravity Rat Intestinal flora Gastrointestinal motility Stem cell factor/c-kit signaling pathway

关节镜手术治疗坐骨结节囊肿前瞻性病例对照研究

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中国骨伤 2018年第3期31卷 217-221页

作者：朱迎春贾学文王哲洋王毳金占萍宁波市第一医院浙江大学宁波医院骨科浙江宁波315010

目的 :比较传统切开手术与关节镜技术在治疗坐骨结节囊肿中的临床应用。方法 :自2014年5月至2016年9月对49例坐骨结节囊肿患者采用信封法分为关节镜组和传统切开组。关节镜组24例,男16例,女8例,年龄42~81(64.1±9.3)岁,病程2~36(17.0±9... 详细信息

目的 :比较传统切开手术与关节镜技术在治疗坐骨结节囊肿中的临床应用。方法 :自2014年5月至2016年9月对49例坐骨结节囊肿患者采用信封法分为关节镜组和传统切开组。关节镜组24例,男16例,女8例,年龄42~81(64.1±9.3)岁,病程2~36(17.0±9.1)个月,在囊肿周围建立人工腔隙,关节镜下刨削清理囊肿壁。传统切开组25例,男11例,女14例,年龄47~79(61.2±10.6)岁,病程4~36(17.5±8.5)个月,分别于术后1 d、1周、1个月时采用肿块表面横行切口,分离切除肿块。比较两组患者手术时间、术后引流量、术后住院天数、术后并发症,并采用疼痛视觉模拟评分(VAS)进行疼痛评价。结果:49例患者均获得随访,时间6~18(11.3±3.3)个月。传统切开组2例出现术后切口感染,1例术后复发,关节镜组均Ⅰ期愈合;关节镜组手术时间、术中出血量、术后引流量、住院天数分别为(54.7±7.7)min、(20.8±3.5)ml、(20.3±5.6)ml、(2.8±0.6)d,均明显优于传统切开组的(71.8±8.8)min、(67.3±12.0)ml、(103.6±20.3)ml、(7.8±2.9)d。关节镜组术后1 d、1周、1个月VAS评分为(2.6±0.7、0.5±0.6、0.3±0.5)显著低于传统切开组的(6.0±0.7、3.0±1.0、1.1±1.0),差异有统计学意义(P0.05)。结论:与传统切开手术相比,关节镜治疗坐骨结节囊肿具有创伤小、围手术期出血量少、术后疼痛程度轻、安全性高以及恢复快等特点,但要求术者有关节镜手术经验,值得在临床实践中推广使用。

关键词：坐骨骨囊肿关节镜病例对照研究

High Efficiency ELID Grinding of Garnet Ferrite

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High Efficiency ELID Grinding of Garnet Ferrite

Thermoelastic stress analysis of multilayered films in a micro-thermoelectric cooling device

第十届国际制造工程与管理会议

作者： ZHANG Fei-hu, QIU Zhong-jun, RANG Gui-wen, YUAN zhe-jun, yang Yong-shan, SHI Xing-kuan(1. Department of Mechanical Manufacturing and Automation,Harbin Institute of Technology, Harbin 150001, China 2. Beijing Radio Measuring Institute, Beijing 100854, China)

＜正＞ Hard and brittle materials such as ferrite, optical glass and ceramics have been widely used in many fields because of their good characteristics and still gain more attentions. However, it is difficult to machine and get good surface quality. Some parts made of these materials have large machining allowances and need to be produced with large batch, but the machining efficiency is very low with usual grinding method. So it is of great importance to research the high efficiency grinding technology of hard and brittle materials. Electrolytic in-process dressing （ELID） grinding is a new grinding technology which has been adopted to the ultra-precision machining of hard and brittle materials. With the function of in-process dressing of metal bond diamond and CBN wheel, ELID grinding has the ability to keep the sharpness of the wheel surface and is widely used in fine abrasive grinding, but it also has the potentialities to high efficiency grinding. In this paper, the mechanism of ELID grinding and its grinding performance are analyzed, then the cast iron bond diamond wheels and ELID grinding device are used on a surface grinder to research the feasibility of ELID grinding to high efficiency grinding. To make comparison, the garnet fer-rite （YAG） work piece has been machined in plunge grinding both by ELID grinding and by the resin bond diamond wheel. The grinding force and surface quality are tested and analyzed. It has been found that the grinding force of the cast iron bond diamond wheel with ELID grinding is apparently smaller than that of the resin bond diamond wheel. Under the same conditions, it is about 2/5-3/5 as the force using the resin bond diamond wheel. So with the same grinder and machining conditions, ELID grinding can machine work piece with greater depth of cut. Because of the smaller grinding force, it is also beneficial to avoid the edge collapse of the work piece and keep the integrity of the grinding surface. This experiment shows that the grin

关键词： grinding ELID grinding hard and brittle material ferrite

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Acta Mechanica Sinica 2012年第6期28卷 1644-1650页

作者： Yu-Mei yang Xing-zhe Wang wen-Jie Zhang Key Laboratory of Mechanics on Environment and Disaster in Western China The Ministry of Education of China College of Civil Engineering and Mechanics Lanzhou University

This paper presents an analytical solution for the thermoelastic stress in a typical in-plane＇s thin-film micro- thermoelectric cooling device under different operating con- ditions. The distributions of the permissible temperature fields in multilayered thin-films are analytically obtained, and the characteristics, including maximum temperature dif- ference and maximum refrigerating output of the thermo- electric device, are discussed for two operating conditions. Analytical expressions of the thermoelastic stresses in the layered thermoelectric thin-films induced by the tempera- ture difference are formulated based on the theory of mul- tilayer system. The results demonstrate that, the geometric dimension is a significant factor which remarkably affects the thermoelastic stresses. The stress distributions in layers of semiconductor thermoelements, insulating and support- ing membrane show distinctly different features. The present work may profitably guide the optimization design of high- efficiency micro-thermoelectric cooling devices.

关键词： Thermoelectric cooling device Multilayeredthin-film Thermoelastic stress - Analytical solution

Biological sources, paleoenvironment, and organic matter enrichment in source rocks of the Ordovician Majiagou Formation, Ordos Basin, China:Evidence from biomarkers,microfossils, and inorganic geochemical analyses

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Journal of Palaeogeography 2024年第1期13卷 92-115页

作者： Jing-Jing Cao wen-zhe Gang Shang-Ru yang State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Bejing)Beijing 102249China College of Geosciences China University of Petroleum(Bejing)Beijing 102249China Oil and Gas Technology Research Institute PetroChina Changqing Oifield CompanyXi'an 710018Shaanxi ProvinceChina

Carbonate deposits in the Ordovivian Majiagou Formation are significant source rocks for natural gas generation in the Ordos Basin, northwestern China. Previous studies mainly focused on the organic matter enrichment mechanism of shales rather than carbonate rocks. The biological sources and paleoenvironment of carbonate source rocks, and the main controlling factors of organic matter enrichment in the carbonate source rocks were studied in this paper in combination with evidence from biomarkers, microfossils and inorganic geochemistry analysis. The results show that four types of microfacies were identified in the Majiagou Formation, respectively as: mud flat microfacies, mud-dolomite flat microfacies, dolomite flat microfacies, and open marine microfacies. The biological sources of organic matter are chiefly planktonic algae, followed by bacteria. The mud flat and mud-dolomite flat contain a high abundance of terrigenous detrital inputs, as indicated by the high content of Al_(2)O_(3), TiO_(2), Th, and Zr. The low Sr/Cu and high Rb/Sr values reveal warm and humid paleoclimate conditions in the mud flat and mud-dolomite flat, whereas the dolomite flat and open marine were likely formed in hot and arid paleoclimate conditions. The mud flat and mud-dolomite flat deposits were characterized by high paleoproductivity of the Majiagou Formation. Low Sr/Ba values were found in the mud flat samples, indicating fresh to brackish water condition, whereas samples of other facies have a relatively high degree of salinity. Based on U_(auth), Mo_(auth), Cr_(auth), Co_(auth), δCe, and δEu values, the mud flat microfacies was formed in a suboxic and anoxic environment, whereas the mud-dolomite flat, dolomite flat and open marine microfacies were within dysoxic to oxic conditions. A model of organic matter enrichment in the Majiagou Formation is thus established. The level of terrigenous detrital inputs is the principal factor of organic matter enrichment in the Majiagou Formation,

关键词： Biological source Microfacies Trace elements Organic matter Majiagou Formation Ordos Basin

Ultra-lightweight CNN design based on neural architecture search and knowledge distillation: A novel method to build the automatic recognition model of space target ISAR images

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Defence Technology（防务技术） 2022年第6期18卷 1073-1095页

作者： Hong yang Ya-sheng Zhang Can-bin Yin wen-zhe Ding Space Engineering University Beijing101416China Beijing Institute of Tracking and Telecommunications Technology China

In this paper,a novel method of ultra-lightweight convolution neural network(CNN)design based on neural architecture search(NAS)and knowledge distillation(KD)is *** can realize the automatic construction of the space target inverse synthetic aperture radar(ISAR)image recognition model with ultra-lightweight and high *** method introduces the NAS method into the radar image recognition for the first time,which solves the time-consuming and labor-consuming problems in the artificial design of the space target ISAR image automatic recognition model(STIIARM).On this basis,the NAS model’s knowledge is transferred to the student model with lower computational complexity by the flow of the solution procedure(FSP)distillation ***,the decline of recognition accuracy caused by the direct compression of model structural parameters can be effectively avoided,and the ultralightweight STIIARM can be *** the method,the Inverted Linear Bottleneck(ILB)and Inverted Residual Block(IRB)are firstly taken as each block’s basic structure in *** the expansion ratio,output filter size,number of IRBs,and convolution kernel size are set as the search parameters to construct a hierarchical decomposition search ***,the recognition accuracy and computational complexity are taken as the objective function and constraint conditions,respectively,and the global optimization model of the CNN architecture search is ***,the simulated annealing(SA)algorithm is used as the search strategy to search out the lightweight and high accuracy STIIARM *** that,based on the three principles of similar block structure,the same corresponding channel number,and the minimum computational complexity,the more lightweight student model is designed,and the FSP matrix pairing between the NAS model and student model is ***,by minimizing the loss between the FSP matrix pairs of the NAS model and student model,the student model’s weight adjust

关键词： Space target ISAR image Neural architecture search Knowledge distillation Lightweight model

聚[甲基丙烯酸(N,N-二乙基氨基乙酯)]的合成

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广州化工 2018年第15期46卷 47-48页

作者：岳文哲钱杨杨危俊吾王雨佳毕韵梅云南师范大学化学化工学院云南昆明650500

聚[甲基丙烯酸(N,N-二乙基氨基乙酯)](PDEAEMA)是一种具有p H响应性的聚合物,可以用作稳定剂、纳米凝胶、水凝胶、生物医用材料等。本文利用2-氯丙酸丙炔酯为引发剂,以氯化亚铜和氯化铜为催化剂,引发甲基丙烯酸(N,N-二乙基氨基乙酯)的... 详细信息

聚[甲基丙烯酸(N,N-二乙基氨基乙酯)](PDEAEMA)是一种具有p H响应性的聚合物,可以用作稳定剂、纳米凝胶、水凝胶、生物医用材料等。本文利用2-氯丙酸丙炔酯为引发剂,以氯化亚铜和氯化铜为催化剂,引发甲基丙烯酸(N,N-二乙基氨基乙酯)的原子转移自由基聚合(ATRP),合成出聚[甲基丙烯酸(N,N-二乙基氨基乙酯)](PDEAEMA),并用核磁共振氢谱(1H NMR)证实了产物的结构。

关键词：聚[甲基丙烯酸(N,N-二乙基氨基乙酯)](PDEAEMA) 原子转移自由基聚合(ATRP) 核磁共振氢谱

Stability of a rat model of prehepatic portal hypertension caused by partial ligation of the portal vein

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World Journal of Gastroenterology 2009年第32期15卷 4049-4054页

作者： zhe wen Jin-zhe Zhang Hui-Min Xia Chun-Xiao yang Ya-Jun Chen Department of Surgery Guangzhou Children's Hospital Affiliated to Guangzhou Medical CollegeGuangzhou 510120 Guangdong Province China Department of Surgery Beijing Children's Hospital Affiliated to Capital Medicai University Beijing 100045 China Department of Surgery Linzi People's Hospital Zibo 255400 Shandong Province China

AIM： To study the stability of portal hypertension （PHT） caused by partial ligation of the portal vein ligation （PVL） in a rat model.METHODS： Thirty male adult Wistar rats were divided into two groups： 10 in Group Ⅰ received a sham operation; and 20 in Group Ⅱreceived partial PVL. Portal vein pressure （PVP） was measured at four time periods： before ligation, 2 wk, 6 wk and 10 wk postsurgery. Portal venography, blood sampling and liver and spleen pathological examinations were conducted at 10 wk after surgery.RESULTS： The PVP was 9.15± 0.58 cmH2O before ligation, and increased to 17.32 ±0.63 cmH2O 2 wk after PVL. By repeat measurement of the PVP in each rat, it was shown to remain elevated for 10 wk. There were no significant differences in the pressure measurements at 2 wk, 6 wk and 10 wk. Varices were found mainly in the mesenteric vein 2 wk after PVL, which were more obvious later, while these manifestations were similar at week 6 and week 10. Portal venography demonstrated the varices and collaterals. There was no significant change in liver pathology. The volume of the spleen was enlarged 2-fold after ligation, and the sinus of the spleen was enlarged due to congestion. Significant sinus endothelial cell proliferation was observed, but no evidence of hypersplenia was found on hemogram and biochemical examination.CONCLUSION： These findings suggest that a satisfactory prehepatic PHT rat model can be obtained by partial ligation of the portal vein, and this PHT rat model was stable for at least 10 wk.

关键词： Ligation Portal hypertension Portal vein Rat