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Experiment and Simulation for Rolling of Diamond–Cu Composites

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Acta Metallurgica Sinica(English Letters) 2017年第8期30卷 791-800页

作者： Yun-Long Wang Kai-Kun Wang Yu-Wei Wang guang-chen li School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Department of Engineering University of LeicesterUniversity Road Leicester LE1 7RH UK Tianjin Xiangtong Electronic Company LTD Tianjin 301800 China

We demonstrate an innovative preparation approach of diamond/Cu composites by powder-in-tube technique and rolling. A small copper tube was loaded with Ti- and Cu-coated diamond particles, mad then the diamond particles were combined with Cu matrix by composite rolling. The morphology and element distribution of the interface between diamond and Cu were determined by scanning electron microscopy and energy-dispersive spectrometer. Finite element method （FEM） simulation was used to analyze the rolling process associated with experiment by DEFORM-3D. The final experimental results showed that homogeneous distribution of diamond particles could be observed in the center layer of the composites. According to the contrast experiments, the sample, whose diamond particle size is 0.12-0.15 mm and thickness of pre-rolling is 1.2 mm, showed relatively complete morphologies and homogeneous distribution. Experimental results indicated a poor efficacy of excessive rolling reduction. The thermal conductivity of the composites is about 453 W （m K）-1 by theoretical calculation. For FEM simulation, roiling strain and temperature field of the composites were simulated by DEFORM-3D. Simulation results were interpreted, and numerical results verified the reliability of the model. The simulation predicted that the local area of large strain, indicative of the strain along the thickness direction, could be intensified by adding diamond particles.

关键词： Diamond/Cu composites Powder-in-tube technique (PIT) Rolling Finite element method(FEM) simulation

Development of a large-scale isolation chamber system for the safe and humane care of medium-sized laboratory animals harboring infectious diseases

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第10期11卷 771-778页

作者： Xin PAN Jian-cheng QI Ming LONG Hao liANG Xiao chen Han li guang-bo li Hao ZHENG Department of Microbiology the Second Military Medical University Shanghai 200433 China

The close phylogenetic relationship between humans and non-human primates makes non-human primates an irreplaceable model for the study of human infectious *** this study,we describe the development of a large-scale automatic multi-functional isolation chamber for use with medium-sized laboratory animals carrying infectious *** isolation chamber,including the transfer chain,disinfection chain,negative air pressure isolation system,animal welfare system,and the automated system,is designed to meet all biological safety *** create an internal chamber environment that is completely isolated from the exterior,variable frequency drive blowers are used in the air-intake and air-exhaust system,precisely controlling the filtered air flow and providing an air-barrier protection.A double door transfer port is used to transfer material between the interior of the isolation chamber and the outside.A peracetic acid sterilizer and its associated pipeline allow for complete disinfection of the isolation *** of the isolation chamber parameters can be automatically controlled by a programmable computerized menu,allowing for work with different animals in different-sized cages depending on the research *** large-scale multi-functional isolation chamber provides a useful and safe system for working with infectious medium-sized laboratory animals in high-level bio-safety laboratories.

关键词： Multi-function Medium-sized animal Isolation chamber Biological safety

Numerical Study on the Whole Process of Fireball Evolution in Strong Explosion

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Communications in Theoretical Physics 2019年第11期71卷 1388-1392页

作者： Yin Xia Chuang Xue chen-guang li guang-Wei Meng Ying-Kui Zhao Jun Yan Bai-Wen li Institute of Applied Physics and Computational Mathematics

With the actual mean free path for radiation in air and a simplified nuclear device, a one-dimension simulation research on fireball phenomenon in a sea level atmosphere is carried out based on the multi-group radiation hydrodynamic codes(RDMG). It is shown that our theoretical calculations can describe the whole process of the fireball evolution for strong explosions from the early X-ray expansion stage to the shock wave propagation stage. The radius of the shock wave and the brightness of the fireball are in good agreement with the experimental results. The whole thermal radiation power curve of the fireball evolution for strong atmospheric explosion at sea level is plotted for the first time. The impact of radiation opacity of the nuclear device material on the early fireball phenomenon is also studied. It is found that trajectories of the radiation fronts and case shocks change with the opacity of equivalent device *** our simulations, we find that only the early fireball depends on the details of the nuclear device, and after the formation of main shock, the evolution is determined by the properties of hot air for strong atmospheric explosion.

关键词： fireball phenomenon radiation transfer equation the shock wave brightness

Diffusion MRI studies of experimental animal models and patients with stroke

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Chinese Medical Journal 1999年第2期 81-86页

作者： Zheng guang chen, Tieqiang li and Tomas Hindmarsh

Abstract Purpose This overview summarises the diffusion magnetic resonance imaging (MRI) results both from the experimental animal model studies and clinical investigations in acute cerebral ischemic *** Sources An English literature searched using MEDliNE (1990-1997).Study Selection Over 80 papers and reviews published in the last eight years and our partial results were *** and Conclusions Diffusion weighted magnetic resonance imaging (DWI) has been extensively used to study acute cerebral ischemia both in experimental animal models and in patients. DWI yields signal intensity contrast modulated by water molecular self diffusion. By recording a series of DWI with different amplitudes of the displacement encoding gradient, the apparent diffusion coefficient (ADC) can be quantitatively mapped. DWI combined with quantitative ADC mapping can provide earlier and more precise evaluation of the ischemic zones. However, the biophysical mechanisms behind the decreased ADC in acute cerebral ischemia are still not fully understood.

关键词： MRI studies experimental animal models Diffusion and

Gamma ray multiplicity of a^(240)Pu solid sphere simulated by JMCT

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Nuclear Science and Techniques 2022年第5期33卷 8-15页

作者： Huan-Huan Ding Fan Gao Chang-Bing Lu Rui li chen-guang li Zhao-Hong Mo Dun-Fu Shi Ming Su De-Shan Zhao Mao-Bing Shuai Zhong-Hua Xiong Bin-Yuan Xia Yun Bai Institute of Materials China Academy of Engineering PhysicsMianyang 621908China The 93147th Unit of PLA Mianyang 621000China CAEP Software Center for High Performance Numerical Simulation Beijing 100088China Institute of Applied Physics and Computational Mathematics Beijing 100088China

Determining the mass of plutonium metal is an important research objective in the field of nuclear material accounting and *** on the 3D neutron and photon transport code JMCT(Jointed Monte Carlo Transport),the gamma ray multiplicity of ^(240)Pu was simulated in this study,and the average number of gamma rays leaking from ^(240)Pu solid spheres with different masses was also *** simulation results show that there is a oneto-one correspondence between the average number of gamma rays and the mass of ^(240)Pu solid spheres in the range of 0.50–3.00 *** result provides a basis for using the average number of gamma rays to account for the mass of ^(240)Pu.

关键词： ^(240)Pu JMCT Gammaraymultiplicity Solid sphere mass Surface-to-volumeratio

Magnetic compression anastomosis for reconstruction of digestive tract after total gastrectomy in beagle model

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World Journal of Gastrointestinal Surgery 2023年第7期15卷 1294-1303页

作者： Miao-Miao Zhang chen-guang li Shu-Qin Xu Jian-Qi Mao Yu-Han Zhang Ai-Hua Shi Yan li Yi Lyu Xiao-Peng Yan Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710061Shaanxi ProvinceChina National Local Joint Engineering Research Center for Precision Surgery&Regenerative Medicine The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710061Shaanxi ProvinceChina Department of Critical Care Medicine China-Japan Union Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Zonglian College Xi'an Jiaotong UniversityXi'an 710061Shaanxi ProvinceChina Qide College Xi'an Jiaotong UniversityXi'an 710061Shaanxi ProvinceChina

BACKGROUND Magnetic compression anastomosis(MCA)is a simple procedure contributing to a reliable ***,digestive-tract reconstruction after total gastrectomy using MCA has not yet been *** To investigate the feasibility of MCA for simultaneous esophagojejunostomy and jejunojejunostomy after total gastrectomy using beagle *** Sixteen beagles were randomly divided into an MCA group(study group,n=8)and a manual-suture anastomosis group(control group,n=8).Two different magnetic anastomosis devices were used in the study group for esophagojejunal and jejunojejunal *** devices included a pair of circular daughter and parent magnets *** time of esophagojejunostomy and jejunojejunostomy,postoperative complications,and survival rate of the two groups were *** dogs were sacrificed one month after the operation and their anastomotic specimens were *** was observed by the naked eye and a light *** Digestive-tract reconstruction after total gastrectomy was successfully completed in both groups(survival rate=100%).In the study group,esophagojejunal and jejunojejunal anastomoses took 6.13±0.58 and 4.06±0.42 min,respectively,significantly lower than those in the control group(15.63±1.53 min,Plications such as bleeding,anastomotic leakage,and anastomotic stenosis were not *** the study group,the magnets did not interfere with each *** time of the jejunojejunal magnetic anastomosis device was 10.75±1.28 d,while that of the esophagojejunal magnetic anastomosis device was 12.25±1.49 *** silk was found in the control *** study group showed a greater smoothness of the anastomosis than that of the control *** layers of anastomosis healed well in both *** MCA is a safe and feasible procedure for digestive-tract reconstruction after total gastrectomy in this animal model.

关键词： Magnetic surgery Magnetic compression anastomosis Gastric cancer Total gastrectomy Roux-en-Y esophagojejunal anastomosis Beagles

Fetal central nervous system anomalies: comparison of magnetic resonance imaging and ultrasonography for diagnosis

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Chinese Medical Journal 2006年第15期119卷 1272-1277页

作者： WANG guang-bin SHAN Rui-qin MA Yu-xiang SHI Hao chen li-guang liU Wen QIU Xiu-ling WEI Yu-long GUO li QU Lei li Hui-hua Shandong Medical Imaging Research Institute Jinan 250021 China Jinan Maternity and Child Care Hospital Jinan 250001 China

Background Evaluation of fetal central nervous system （CNS） agenesis by ultrasonography （US） is frequently limited, but magnetic resonance imaging （MRI） has its own advantages and is gaining popularity in displaying suspected fetal anomalies. The purpose of this study was to explore the value of MRI in detecting fetal CNS agenesls. Methods Thirty-four women （aged from 22 to 35 years, average 27 years） with complicated pregnancies （16-- 39 weeks of gestation, average 30 weeks） were examined with a 1.5 T superconductive MR unit within 24 hours after ultrasonography. Half-Fourier acquisition single-shot turbo spin-echo （HASTE） T2-weighted imaging （T2WI） sequence were performed in all patients, and fast low angle shot （FLASH） T1-weighted imaging （T1WI） sequence were applied sequentially in seven of them. Comparison of the results was made between the MRI and US findings as well as autopsy or postnatal follow-up MRI findings. Results The gyms, sulcus, corpus callosum, thalamus, cerebellum, brainstem, and spinal cord of fetus were shown more clearly on T2-weighted MR images than on T1-weighted MR images. MRI corrected the diagnosis of US in 10 cases （10/34, 29.41%） and the diagnosis was missed only in 1 case （1/34, 2.94%）. Conclusion MRI has advantages to US in detecting fetal CNS anomalies and is a supplement to US in complicated pregnancies.

关键词： fetus central nervous system abnormality magnetic resonance imaging ultrasonography

A new sequential two-stent strategy for treating true distal left main trifurcation lesion

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Journal of Geriatric Cardiology 2021年第6期18卷 487-491页

作者： Yu-Xiang DAI chen-guang li Jia HUANG Ren-De XU Shu-Fu CHANG Hao LU Dao-Yuan REN Lei GE Ju-Ying QIAN Feng ZHANG Jun-Bo GE Department of Cardiology Zhongshan HospitalFudan UniversityShanghai Institute of Cardiovascular DiseasesShanghaiChina

The incidence of significant left main(LM)coronary artery stenosis identified by coronary angiography was 5%−17.5%in various clinical presentations;about 80%of stenosis involved the LM bifurcation(LMB).[1]Although per-cutaneous coronary intervention(PCI)is an appro-priate alternative to coronary artery bypass graft in LM disease with low-to-intermediate anatomical complexity,[2]PCI for LMB lesions remains the most technically challenging for interventional cardiolo-gists with higher rates of acute periprocedural com-plications and higher risk of long-term major ad-verse cardiac events in the era of drug-eluting stent(DES).

关键词： stenosis acute bypass

Primary animal experiment to test the feasibility of a novel Y-Z magnetic hepatic portal blocking band

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World Journal of Gastrointestinal Surgery 2023年第7期15卷 1286-1293页

作者： Miao-Miao Zhang chen-guang li Shu-Qin Xu Jian-Qi Mao Yu-Xiang Ren Yu-Han Zhang Jia Ma Ai-Hua Shi Yi Lyu Xiao-Peng Yan Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710061Shaanxi ProvinceChina National Local Joint Engineering Research Center for Precision Surgery&Regenerative Medicine The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710061Shaanxi ProvinceChina Department of Critical Care Medicine China-Japan Union Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Zonglian College Xi'an Jiaotong UniversityXi'an 710061Shaanxi ProvinceChina Qide College Xi'an Jiaotong UniversityXi'an 710061Shaanxi ProvinceChina Department of Surgical Oncology Shaanxi Provincial People's HospitalXi'an 710068Shaanxi ProvinceChina

BACKGROUND Hepatic portal blood flow occlusion is a common technique for reducing hepatic hemorrhage during *** designed a novel Y-Z magnetic hepatic portal blocking band(Y-Z MHPBB)based on the principle of magnetic compression *** To introduce the Y-Z MHPBB device and verify the feasibility of this device for hepatic portal blood flow occlusion in *** Ten beagles were randomly divided into the experimental group and control *** operation time,intraoperative blood loss,the number of portal blood flow occlusions,the total time spent on adjusting the blocking band,and the average time spent on adjusting the blocking band were *** surgeons evaluated the feasibility and flexibility of the two portal occlusion *** Laparoscopic hepatectomy was successfully performed in both the experimental group and control *** was no statistical difference between the two groups in the operation time,intraoperative blood loss,and the number of hepatic portal blood flow *** respect to the total time spent on adjusting the blocking band and the average time spent on adjusting the blocking band,the experimental group showed significantly better outcomes than the control group,with a statistical difference(Plity;and it can be used for hepatic portal blood flow occlusion during laparoscopic hepatectomy.

关键词： Hepatic portal blood flow occlusion Laparoscopic hepatectomy Novel Y-Z magnetic hepatic portal blocking band Magnetic surgery Magnetic compression technique Beagles