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LEVEL SET METHOD FOR NUMERICAL SIMULATION OF A CAVITATION BUBBLE COLLAPSING NEAR A RIGID WALL

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Journal of Hydrodynamics 2005年第6期17卷 647-653页

作者： HUANG jun-tao zhang Hui-sheng Department of Mechanics and Engineering Science Fudan University Shanghai 200433 China

The level set method, TVD scheme of second order upwind procedure coupled with flux limiter, ENO velocity extension procedure inside the huhble, and MAC projection algorithm were incorporated to simulate the whole collapse e volution of a cavitation bubble near a rigid wall with many complicated phenomena, such as topology distortion and shrinking, jet impact, bubble breaking into a toroidal form, and diminishing volume to zero, etc. The huhhle shape, evolution and distribution of velocity and pressure fields of the fluid during the bubble collapsing were investigated. It is found that the method is numerically stable and has good convergence property, and the results are in good agreements with those in previous work.

关键词： level set method high resolution scheme,MAC projection cavitation hubble collapse toroidal huhhle

Fractionation characteristics of magnesium isotope in the ancient weathering crust

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Petroleum Science 2023年第3期20卷 1446-1457页

作者： Jia-Qi Yang jun-tao zhang Zhi-Liang He Ni-Na Luo Xiao-Hui Jjin tao zhang Ning Gu Kang-jun Huang jian Gao School of Energy Resources China University of GeosciencesBeijing100083China SINOPEC Exploration and Production Research Institute Beijing100083China China Petrochemical Corporation Ltd. Beijing100728China Key Laboratory of Deep Geology and Resources SINOPECBejing102206China Chongqing Gas Field of Petro China Southwest Oil and Gas Field Company Chongqing400021China Shaanxi Key Laboretory of Early Life and Environments Department of GeologyNorthwest UniversityXi'anShaanxi710069China

Weathering has always been a concerned around the world,as the first and most important step in the global cycle of elements,which leads to the fractionation of isotopes on the scale of geological *** Middle Ordovician Majiagou Formation in Daniudi area of the Ordos Basin had experienced weathering for>130 *** thin section observation,major and trace element analysis,carbon,oxygen,and magnesium isotopes composition analysis,the dolomitization modes and weathering of ancient dolo-mite in Daniudi area were analyzed in *** results showed that the Sabkha and brine-reflux dolomitization modes had developed,and the Mg isotopes in different layers of the karst crust were fractionated by various *** vertical vadose zone was affected by weathering,the Mg isotope of dolomite(δ^(26)Mgdol)showed a downward decreasing trend;the horizontal underflow zone was controlled by diagenesis and formation fluid,δ^(26)Mgdol showed a vertical invariance and negative;the main reason for Mg isotope fractionation in the deep slow-flow zone was the brine-reflux dolomitization mode during early burial period,which showed a vertical downward ***,the Mg isotope characteristic data of the ancient weathering crust were provided and the process of Mg isotope frac-tionationinthekarstcrust was explained.

关键词： Magnesium isotope Dolomitization mode Weathering Ancient weathering crust Ordos Basin

CRLB analysis of wireless cognitive location with different short-range measurements

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The Journal of China Universities of Posts and Telecommunications 2008年第2期15卷 1-6页

作者： CUI Qi-mei LIU jun tao Xiao-feng zhang Ping Key Laboratoryof Universal Wireless Communications Beijing University of Posts and Telecommunications Beijing 100876 China

Because of the wide application and great market potential of location-aware services, the research of wireless location techniques for the fourth generation （4G） mobile communications is being paid more attention. Wireless cognitive location （WCL） techniques for next generation wireless networks have been proposed in recent years. This article investigates the changes of the positioning accuracy of WCL algorithm when different methods are adopted to measure the short-range （SR） information. By fJrst completing Cramer-Rao lower bound （CRLB） analysis of the WCL algorithm with SR measurements based on time of arrival （TOA） and received signal strength （RSS）, it is discovered that TOA-based or time difference of arrival （TDOA） -based SR measurement can make WCL algorithms achieve higher accuracy than RSS mode, which is also verified by numerical simulation in the article. The conclusions can instruct the design of novel WCL-based location algorithms.

关键词： wireless cognitive location short range (SR) longrange (LR) Cramer-Rao lower bound (CRLB)

PROGRESS OF CHINESE REGIONAL GEOGRAPHY STUDIES IN RECENT TWENTY YEARS

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Chinese Geographical Science 2000年第1期10卷 90-97页

作者： jun-tao zhang Feng Liu Zhe Li Institute of Geography the Chinese Academy of Sciences 100101 Beijing P. R. China

Regional geography, embodying the regionality and integration, is the kernel of Geography. Since the 1980s, the Chinese geographers have extensively taken part in the social practical activities and made progress in physico geographical regionalization, economic regionalization, territorial (regional) development planning, construction of special economic zone, and integrated research in the major areas of China. Through these works, the theories of regional geography have been richened and the capacity participating in the social practice promoted as well. In China, many regional researches had been conducted respectively from the aspects of regional physico geography and regional economic geography, etc. According to the cases, this paper gives a review on the studies of regional geography during the latest two decades in China. It ought to be indicated that the natural and human components should be combined and the disciplines intersected and permeated, with the support of advanced technology. In order to serve the regional sustainable development, on the background of global change, this is an inevitable tendency for the development of the regional geography.

关键词： regional geography regional physico geography regional economic geography integrated research geographical research

A facile synthesis of the spiroindoline-based growth hormone secretagogue,MK-677

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Chinese Chemical Letters 2012年第6期23卷 661-664页

作者： Xian Liang Qi Er Qun Yang jun tao zhang tao Wang Xiao Ping Cao State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 China

A facile and improved route for the synthesis of the orally active spiroindoline-based growth hormone secretagogue, MK-677 was described. The key step adopted the Fischer indole/reduction strategy. The preparation of the key intermediates N-protected piperidine carboxaldehyde 5 and the N-Boc-O-benzyl-D-serine （2） are also optimized.

关键词： MK-677 Synthesis Improved route Fischer indole/reduction

A LEVEL SET METHOD FOR SIMULATION OF RISING BUBBLE

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Journal of Hydrodynamics 2004年第4期16卷 379-385页

作者： HUANGjun-tao zhangHui-sheng DepartmentofMechanicsandEngineeringSciences FudanUniversityShanghai200433China

A level set method, the TVD scheme of second-order upwind procedure coupledwith flux-limiter, and SIMPLE algorithm were incorporated to simulate the flow and interfacialmotion of immiscible two-fluids with large density ratio and viscosity ratios, large topologydistortion and surface tension. As a numerical example axi-symmetric rising bubbles wereinvestigated. It is found that the method is numerically stable and has good convergence propertyand the results are in good agreement with other works.

关键词： level set method high-resolution scheme SIMPLE algorithm rising bubble

COVID-19 or treatment associated immunosuppression may trigger hepatitis B virus reactivation: A case report

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World Journal of Clinical Cases 2021年第19期9卷 5266-5269页

作者： Yi-Feng Wu Wan-jun Yu Yu-Hua Jiang Yin Chen Bo zhang Rui-Bing Zhen jun-tao zhang Yi-Ping Wang Qiang Li Feng Xu Yan-jun Shi Xian-Peng Li Department of Hepatobiliary and Pancreas Surgery The Affiliated People’s Hospital of Ningbo UniversityNingbo 315040Zhejiang ProvinceChina Department of Respiratory Disease and Critical Care Medicine The Affiliated People’s Hospital of Ningbo UniversityNingbo 315040Zhejiang ProvinceChina Department of Infectious Diseases The Affiliated People’s Hospital of Ningbo UniversityNingbo 315040Zhejiang ProvinceChina Department of Ophthalmology The Affiliated People’s Hospital of Ningbo UniversityNingbo 315040Zhejiang ProvinceChina Department of Laboratory Medicine The Affiliated People’s Hospital of Ningbo UniversityNingbo 315040Zhejiang ProvinceChina Department of Radiology The Affiliated People’s Hospital of Ningbo UniversityNingbo 315040Zhejiang ProvinceChina Department of Gastroenterology The Affiliated People’s Hospital of Ningbo UniversityNingbo 315040Zhejiang ProvinceChina Department of Hepatobiliary and Pancreas Surgery The Second Affiliated Hospital Zhejiang University School of MedicineHangzhou 315009Zhejiang ProvinceChina

BACKGROUND Since the initial recognition of coronavirus disease 2019(COVID-19)in Wuhan,this infectious disease has spread to most areas of the *** pathogenesis of COVID-19 is yet *** B virus(HBV)reactivation occurring in COVID-19 patients has not yet been *** SUMMARY A 45-year-old hepatitis B man with long-term use of adefovir dipivoxil and entecavir for antiviral therapy had HBV reactivation after being treated with methylprednisolone for COVID-19 for 6 *** COVID-19 or treatment associated immunosuppression may trigger HBV reactivation.

关键词： COVID-19 Hepatitis B virus Reactivation Diagnose Therapy Case report

Molecular Characterization and Expression Pattern of Rheb Gene in Inner Mongolia Cashmere Goat(Capra hircus)

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Agricultural Sciences in China 2011年第9期10卷 1452-1458页

作者： ZHENG Xu YANG Jiao-fu WANG Xiao-jing LIANG Yan WU Man-lin SHI Jie-jun zhang tao QIN Yin LI Shu-yu HAO Xi-yan WANG Zhi-gang LIU Dong-jun College of Life Science lnner Mongolia University/Key Laboratory of Mammal Reproductive Biology and Biotechnology Ministry of Education Hohhot 010021 P.R.China

As one member of the Ras super family, Rheb is an upstream regulator of mTOR signaling pathway, which regulates the process of cell-growth, proliferation and differentiation. In order to study the relationship between Rheb and mTOR in Inner Mongolian Cashmere goat （Capra hircus） cells, Ras homolog enriched in brain （Rheb） gene eDNA was amplified by RT-PCR. It is 555 bp in length and includes the complete ORF encoding 184 amino acids （GenBank accession no. HM569224）. The full eDNA nucleotide sequence has a 99% identity with that of sheep, 98% with cattle and 93% with human while their amino acids sequence shares identity with 98, 97 and 97% of them, correspondingly. The bioinformatics analysis showed that Rheb has a Ras family domain, two casein kinase II phosphorylation sites, two ATP/GTP-binding sites motifA （P-loop）, a prenyl group binding site （CAAX box）. Tissue-specific expression analysis performed by semi- quantitative RT-PCR. The Rheb gene was expressed in all the tested tissues and the highest level ofmRNA accumulation was detected in brain, suggesting that Rheb played an important role in goat cells.

关键词： Inner Mongolia Cashmere goat Rheb gene expression pattern

Protective effects of ischemic postconditioning on intestinal mucosa barrier function in rabbits with crush injury of hind limb： an experimental study

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Chinese Journal of Traumatology 2011年第2期14卷 92-95页

作者： DING jun-tao zhang Lian-yang Trauma Center of PLA State Key Laboratory of Trauma Burns and Combined Injury Research Institute of Surgery Daping Hospital Third Military Medical University Chongqing 400042 China

Objective： To explore the protective effects of two types of ischemic postconditioning （IP） on intestinal mucosa barrier in rabbits with crush injury of the hind limb. Methods： This study was conducted between August and December 2008 in the Department of Trauma Surgery, Daping Hospital, Third Military Medical University, Chongqing, China. The model of crush injury to the hind limb of rabbits was firstly developed by a 25 kg object with the right hind limbs fixed by wooden splints, and then two types of IP were established, including occluding/opening the common iliac artery and vein alternatively （traditional IP, IP A） and binding/loosening the proximum of the injured hind limb altematively （modified IP, IP B）. Thirty-six male New Zealand white rabbits were randomly divided into three groups： IP A group, IP B group and control group, with 12 rabbits in each group. The serum levels of diamine oxidase （DAO） and intestinal fatty acid-binding protein （I-FABP） were detected at 2, 6, 12 and 24 hours after injury. Pathologi- cal changes of ileum were examined at 24 hours after injury. Results： The serum levels of I-FABP at 2, 6, 12 and 24 hours after injury in both IPA and IP B groups had a significant decrease, compared with control group. DAO levels also showed the same change trend at 2 and 6 hours after injury, but showed no significant difference between two IP groups. No difference in pathological changes of ileum was found among the three groups. Conclusions： IP can protect intestinal mucosa barrier function on the model of hind limb crush injury in rabbits. Meanwhile the modified IP B shows the same protection as the traditional IP A, and is worth applying in clinic.

关键词： Ischemic postconditioning Crush syndrome Intestinal mucosa