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A transient single particle model under FCI conditions

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Nuclear Science and Techniques 2005年第5期16卷 315-320页

作者： LI Xiao-Yan SHANG zhi xu Ji-jun Department of Nuclear Science and System Engineering School of Mechanics and Power Shanghai Jiaotong University Shanghai 200030

The paper is focused on the coupling effect between film boiling heat transfer and evaporation drag around a hot-particle in cold liquid. Based on the continuity, momentum and energy equations of the vapor film, a transient two-dimensional single particle model has been established. This paper contains a detailed description of HPMC (High-temperature Particle Moving in Coolant) model for studying some aspects of the premixing stage of fuel-coolant interactions (FCIs). The transient process of high-temperature particles moving in coolant can be simu-lated. Comparisons between the experiment results and the calculations using HPMC model demonstrate that HPMC model achieves a good agreement in predicting the time-varying characteristic of high-temperature spheres moving in coolant.

关键词： FCI 热物理学瞬时模型热力工程

Interference Pattern of Density-Density Correlation for Incoherent Atoms with Vortices Released from an Optical Lattice

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Chinese Physics Letters 2011年第1期28卷 26-29页

作者： xu zhi-jun ZHANG Dong-Mei LIU Xia-Yin College of Science Zhejiang University of Technology Hangzhou 310023

For a series of incoherent condensate atomic clouds with vortices （an orbital angular momentum） released from an optical lattice, the density-density correlation function of this freely expanding ultracold gases is theoretically investigated. It is shown that the nonzero angular momentum of the atoms has an important effect on the fringe pattern of density-density correlation. Particularly, for a short expansion time, even the rotation direction of the atoms could have an observable effect on the fringe pattern. Observation of this specific fringe pattern would constitute experimental evidence for the presence of a vortex in an atomic condensate.

关键词： Quantum gases, liquids and solids Optics, quantum optics and lasers Statistical physics and nonlinear systems

Anticancer effect of Jinlongshe granules on in situ-transplanted human MKN-45 gastric cancer in nude mice and xenografted sarcoma 180 in Kunming mice and its mechanism

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World Journal of Gastroenterology 2006年第18期12卷 2890-2894页

作者： zhi-Hong Yu Pin-Kang Wei Ling xu zhi-Feng Qin jun Shi Department of Traditional Chinese Medicine Changzheng Hospital Second Military Medical University Shanghai 200003 China

AIM： To study the antitumor effect of Chinese compound Jinlongshe （JLS） granules on sarcoma 180 and MKN-45 human gastric cancer cell lines in vivo and its mechanism. METHODS： After establishment of S180 sarcoma （S180） and MKN-45 gastric cancer model of nude mice, the tumor-bearing mice were divided into 5 groups at random. Three experimental groups were respectively given the aqueous extract of JLS granules at doses of 120 g, 60 g and 20 g/（kg per 6/wk,i.g） for 3 wk in S180 and 6 wk in nude mice model. Positive control was given cyclophosphamide （Cy） at a dose of 50 mg/（kg per 3/wk, i.g） for 3 wk in S180 models and 5-Fluorouracil （5-FU） 20 mg/（kg per 3/wk, i.g） for 3 wk in nude mice model. Negative control was given normal saline （NS） at a dose of 0.18 g/（kg per 6/wk, i.g） respectively. After 3 wk in mice bearing S180 tumor and 6 wk in nude mice model, the experimental animals were sacrificed and the masses of tumor were weighed, and the rates of tumor inhibition of each treated group were calculated respectively. To determine the antitumor mechanisms, the morphological changes, cell cycle and apoptosis were observed in MKN-45 nude mice model. Annexin V-FITC/PI double staining FCM assay was used to further determine the live cells, apoptotic cells, necrotic cells and debris. RESULTS： The inhibitory rates of JLS granules at the doses of 20 g/kg, 60 g/kg and 120 g/kg were 50.31%, 55.94% and 68.13% （P 〈 0.01） in nude mice models and 40.90%, 50.32% and 58.46% （P 〈 0.01） in S180 model. The inhibitory rate of Cy was 85.22% in S180 models and the inhibitory rate of 5-FU was 53.43% in nude mice model （P 〈 0.01）. Nuclear chromatin and margination were observed under a transmission electron microscope （TEM）. The G0/G1 phase was arrested, typical apoptotic peak appeared, the apoptotic rate was 22.81%-38.54% in three JLS granule-treated groups. Annexin V-FITC/PI double staining FCM assay showed that the apoptotic cells were 4.36%, 3.08% and 7.08% in three dosages, most cell

关键词： Jinlongshe granules Sarcoma 180 Human MKN-45 gastric cancer lines Traditional Chinese medicine

Target reliability index for serviceability limit state of single piles

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Journal of Central South University 2015年第1期22卷 310-316页

作者：边晓亚郑俊杰徐志军章荣军 School of Civil Engineering & Mechanics Huazhong University of Science and Technology School of Civil Engineering and Architecture Henan University of Technology

The objective is to develop an approach for the determination of the target reliability index for serviceability limit state(SLS) of single piles. This contributes to conducting the SLS reliability-based design(RBD) of piles. Based on a two-parameter,hyperbolic curve-fitting equation describing the load-settlement relation of piles, the SLS model factor is defined. Then, taking into account the uncertainties of load-settlement model, load and bearing capacity of piles, the formula for computing the SLS reliability index(βsls) is obtained using the mean value first order second moment(MVFOSM) method. Meanwhile, the limit state function for conducting the SLS reliability analysis by the Monte Carlo simulation(MCS) method is established. These two methods are finally applied to determine the SLS target reliability index. Herein, the limiting tolerable settlement(slt) is treated as a random variable. For illustration, four load test databases from South Africa are compiled again to conduct reliability analysis and present the recommended target reliability indices. The results indicate that the MVFOSM method overestimates βsls compared to that computed by the MCS method. Besides, both factor of safety(FS) and slt are key factors influencing βsls, so the combination of FS and βsls is welcome to be used for the SLS reliability analysis of piles when slt is determined. For smaller slt, pile types and soils conditions have significant influence on the SLS target reliability indices; for larger slt, slt is the major factor having influence on the SLS target reliability indices. This proves that slt is the most key parameter for the determination of the SLS target reliability index.

关键词： single pile serviceability limit state target reliability index mean value first order second moment method Monte Carlo simulation

Construction and Implementation of Expert System for Common Pig Diseases Prevention Based on Struts Framework

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Animal Husbandry and Feed Science 2010年第5期2卷 41-43,48页

作者： xu zhi-jun GAO Feng College of Agriculture Jilin University Changchun 130062 China

The prevention of common pig diseases depends on the experience of veterinarian greatly due to complexity of piggery pestilence. The expert system for the prophylaxis and treatment of common pig diseases is able to make the complex task more effective. The construction and im- plementation of this expert system is based on the bottleneck problems of the traditional expert system knowledge acquisition and the frame descrip- tion of symptoms of common pig diseases, used the knowledge project method and technology, and combined the uncertainty inference and dispel- ling strategy of matching conflict and technology of multimedia. This expert system is used to imitate expert thinking and supplement or substitute for veterinary experts to guide the prophylaxis and treatment of common pig diseases. The overall structure, knowledge expression, inference mecha- nism and system realization would be expounded emphatically.

关键词： Expert system Common pig diseases Prevention Struts frame

Pressure-induced isostructural phase transition in Bi2Sr2CaCu2O8+δ

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Chinese Physics C 2013年第8期37卷 90-93页

作者：张建波唐玲云张弜秦振兴曾小金刘景 WEN Jin-Sheng xu zhi-jun GU Genda 陈晓嘉 Department of Physics South China University of Technology Institute of High Energy Physics Chinese Academy of Science Condensed Matter Physics and Materials Science Brookhaven National Laboratory

The high-pressure structures of an underdoped cuprate superconductor Bi 2 Sr 2 CaCu 2 O 8+δ have been studied by synchrotron X-ray diffraction at pressures up to 36.5 GPa. We find that this superconductor retains its orthogonal structure with the space group Amaa in the pressure range studied. Upon compression, both the a and b axes first shrink monotonically up to 17.4 GPa from their ambient pressure values and keep these behaviors with positive compressibilities up to 36.5 GPa after experiencing expansion with negative compressibilities in the pressure regime between 17.4 and 23.7 GPa. However, the c axis decreases continuously with increasing pressure with a slow change at about 23.7 GPa. The results indicate an isostructural phase transition starting at 17.4 GPa and a structural collapse at around 23.7 GPa.

关键词： cuprate superconductors structural properties high pressure synchrotron X-ray diffraction

GHz band frequency hopping PLL-based frequency synthesizers

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Optoelectronics Letters 2005年第3期1卷 179-181页

作者： xu Yong WANG zhi-gong GUAN Yu xu zhi-jun QIAO Lu-feng The PLA University of Science and Technology Nanjing 211101 China Institute of RF-＆ OE-ICs Southeast University Nanjing 210096 China

In this paper we describe a full-integrated circuit containing all building blocks of a completed PLL-based synthesizer except for low pass filter（LPF）. The frequency synthesizer is designed for a frequency hopping （FH） transceiver operating up to 1.5 GHz as a local oscillator. The architecture of Voltage Controlled Oscillator （VCO） is optimized to get better performance, and a phase noise of -111.85-dBc/Hz @ 1 MHz and a tuning range of 250 MHz are gained at a centre frequency of 1.35 GHz. A novel Dual-Modulus Prescaler（DMP） is designed to achieve a very low jitter and a lower power. The settling time of PLL is 80 μs while the reference frequency is 400 KHz.This monolithic frequency synthesizer is to integrate all main building blocks of PLL except for the low pass filter, with a maximum VCO output frequency of 1.5 GHz, and is fabricated with a 0.18 μm mixed signal CMOS process. Low power dissipation, low phase noise, large tuning range and fast settling time are gained in this design.

关键词：频率合成器同步逻辑单片电路输出频率相位噪音

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玻色凝聚原子云的二次干涉及其放大效应

物理学报 2007年第10期56卷 5607-5612页

作者：徐志君李鹏华浙江工业大学应用物理系杭州320032

捕限在三维轴对称谐振势阱叠加一维光晶格势的组合势中的玻色凝聚气体,取消磁阱和光晶格势后,将形成沿轴向向两侧运动的干涉边峰.提出一个新的实验方案,使这样的干涉边峰再次相遇叠加,以探讨物质波的二次干涉效应.研究表明,在干涉边峰... 详细信息

捕限在三维轴对称谐振势阱叠加一维光晶格势的组合势中的玻色凝聚气体,取消磁阱和光晶格势后,将形成沿轴向向两侧运动的干涉边峰.提出一个新的实验方案,使这样的干涉边峰再次相遇叠加,以探讨物质波的二次干涉效应.研究表明,在干涉边峰相干加强的区域,玻色凝聚原子云的密度会得到有效放大.基于现有的实验技术,这个新实验是可以实现的,这种效应也是可以观测得到的.

关键词：玻色凝聚气体光晶格势干涉边峰干涉

多个子玻色-爱因斯坦凝聚气体膨胀叠加形成的量子涡旋现象研究

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物理学报 2018年第1期67卷 9-17页

作者：董毕远徐志君浙江工业大学应用物理系杭州310023

基于二维模型,研究了多个子玻色-爱因斯坦凝聚气体在谐振势阱内膨胀叠加形成的量子涡旋现象.运用传播子方法,分析了对称分布的三个子玻色-爱因斯坦凝聚气体膨胀叠加形成宏观量子涡旋的物理过程,得到量子涡旋随时间演化的规律;发现涡旋... 详细信息

基于二维模型,研究了多个子玻色-爱因斯坦凝聚气体在谐振势阱内膨胀叠加形成的量子涡旋现象.运用传播子方法,分析了对称分布的三个子玻色-爱因斯坦凝聚气体膨胀叠加形成宏观量子涡旋的物理过程,得到量子涡旋随时间演化的规律;发现涡旋核分布在谐振势阱内出现振荡;涡旋与反涡旋随时间演化而相互转变,并对这些现象进行了物理分析.

关键词：玻色凝聚气体谐振势阱波函数量子涡旋