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Generation of Enhanced Three-Mode Continuously Variable Entanglement

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Chinese Physics Letters 2011年第9期28卷 24-27页

作者： yu you-Bin WANG Huai-jun FENG jin-Xia School of Science Ningbo University of TechnologyNingbo 315211 State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-ElectronicsShanxi UniversityTaiyuan 030006

The generation of enhanced three-mode continuously variable(CV)entanglement via difference-frequency amplification in an optical cavity above the threshold is *** quantum entanglement characteristics among the pump,signal,and idler beams are demonstrated by applying a sufficient inseparability criterion for CV entanglement proposed by van Loock and *** three-mode CV entanglement with different frequencies can be generated in this simple system when the optical cavity operates above its threshold,and the best three-mode CV entanglement can be obtained when the pump threshold parameter is modulated at aboutσ=1.3.

关键词： applying criterion quantum

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高温高压动态点火模拟系统及实验测试

实验技术与管理 2024年第2期41卷 208-214页

作者：陈新远于晓聪关文龙唐君实郑浩然阚长宾中国地质大学(武汉)资源学院湖北武汉430070 中国石油勘探开发研究院提高采收率国家重点实验室北京100083

点火是火烧油层中最重要的一步,关系到燃烧能否成功启动,开展室内实验可以获取点火过程中的动态信息。该文针对燃烧管实验操作复杂和热分析实验难以模拟地层条件的问题,结合原油燃烧过程中高温高压、温度变化迅速的特点,设计了高温高压... 详细信息

点火是火烧油层中最重要的一步,关系到燃烧能否成功启动,开展室内实验可以获取点火过程中的动态信息。该文针对燃烧管实验操作复杂和热分析实验难以模拟地层条件的问题,结合原油燃烧过程中高温高压、温度变化迅速的特点,设计了高温高压动态点火模拟系统。模拟系统使用程序控制可对岩心精准升温,温度控制采样分辨率为0.1℃,模拟系统可承受10 MPa的压力,可实时记录7种气体组分,并可实时动态监测温度压力、尾气组分。功能性实验表明:原油Arrhenius曲线在高低温区域呈现明显差异,曲线在高温区域的线性度较好,相关系数大于0.9,并求得高温区域表观活化能为8.01~26.7k j/mol。测试表明,模拟系统可实时监测记录原油燃烧过程中的氧化参数,为工程实施和数值模拟提供基础数据。

关键词：火烧油层点火参数模拟实验系统表观活化能分析点火评价

Wavelet Image Coding Based on Significance Extraction Using Morpkological Operation

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Wavelet Image Coding Based on Significance Extraction Using ...

Modelling the Anisotropic Effects with the Extended UH Model for Soils

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作者： j.M.Zhong C.H.Leung y.y.Tang Dept.of Electrical & Electronic Engineering The University of Hong Kong Pokfulam Road Hong Kong Dept.of Electrical & Electronic Engineering The University of Hong Kong Pokfulam Road Hong Kong Dept.of Computing Studies Hong Kong Baptist University Kowloon Tong Hong Kong

In this paper, an efficient embedded imagecompression algorithm is presened. It is based on theobservation that the distribution of significantcoefficiens is intra-subband clustered and inter-subbandself-similar. Morphological dilation is used to capture theclustered significant coefficients in each subband,resulting in the partitioning of each subband intosignificance clusters and insignificance space. Thus forentropy coding, different Probability models are used fordifferent regions according to their own probabilitydistributions. When encoding the insignificant space,which contains mostly zeros, investigation reveals thatthe zerotree data structure is not very efficient torepresent zeros across scales for texture images and amore efficient method is presented. Experimental resultsshow that the proposed algorithm is very effectiveespecially for texture images.

关键词：

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Modelling the Anisotropic Effects with the Extended UH Model...

Influence of Montmorillonite Nanocomposite on Tissue Levels of Lead and Blood Biochemical Parameters in Pigs Exposed to Lead

The 16th Annual Conference of Hong Kong Society of Theoretical and Applied Mechanics 2012、The 1st Mainland-Hong Kong youth Forum on Mechanics 2012、The 8th Shanghai-Hong Kong Forum on Mechanics and Its Application 2012

作者： y.X.Kong y.P.yao j.D.Zhao Department of Civil and Environmental Engineering Hong Kong Univ.of Science and Technology Department of Civil Engineering Beihang University

Extended UH model is a three-dimensional（3D） elastoplastic constitutive model that builds on a modification of the UH model with a unified hardening parameter,to account for the effect of anisotropy and the influence of K consolidation on the stress-strain-strength behaviour of *** combined effects of anisotropy and stress magnitude are considered through the minimum value of angles（α） made by the spatially mobilized planes（SMPs） and soil depositional *** original transformed stress tensor is revised by incorporating the anisotropic peak stress ratio M,which is defined as a function ofα,with the stress tensorσ.The comparison with test results on San Francisco Bay Mud demonstrates the capability of the proposed anisotropic *** UH model is extended to account for the combined effects of inherent anisotropy and K conditions on the stress- strain-strength response of anisotropic clays by incorporating the revised transformed stress tensorσ, the potential strength ratio M_f,the characteristic stress ratio M,and the state stress ratioη.A series of undrained triaxial tests on isotropically and anisotropically consolidated specimens with different overconsolidation ratios（OCRs） are successfully predicted using the proposed extended UH model. New parameters for anisotropic soils can be determined conveniently from the conventional triaxial compression tests on vertical and horizontal specimens.

关键词： Modelling the Anisotropic Effects with the Extended UH Model for Soils

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journal of Animal Science and Biotechnology 2010年第1期1卷 44-48页

作者： D.y. yu W.Rao B.Zhou. W.H.Song College of Animal Science Institute of Feed Science Zhejiang University Hangzhou Zhejiang310029 China

ABSTRACT： Eighteen （Duroc x Landrace x yorkshire） castrated boars, 55 days of age and weig- hing approximately 19 kg, were used to investigate the effects of montmorillonite nanocomposite on tissue levels of lead as well as changes in blood biochemical parameters in pigs fed lead contaminated diets. The barrows were randomly assigned to one of three treat- ments （n = 6） including a control which were fed a basal diet based on corn and soybean meal. The re- maining two groups were fed the basal diet supple- mented with 10 mg/kg lead either with or without 0.5% montmorillonite nanocomposite for 50 days. Pigs treated with lead had significantly increased lev- els of lead in their tissues. Lead accumulated in all tis- sues of the body with the highest accumulation found in the hair. When montmorillonite nanocomposite was given along with lead, tissue concentrations of lead did not differ from the control. Fecal excretion of leadincreased significantly in lead-exposed pigs treated with montmorillonite nanocomposite. A progressive and appreciable accumulation of lead was seen in blood with a concomitant increase in zinc protopor- phyrin levels during the course of treatment. Howev- er, zinc protoporphyrin levels did not differ from the control when montmorillonite nanocomposite was ad- ministered along with lead. The activity of ^-amino le- vulinic acid dehydratase in blood was significantly in- creased in lead treated pigs compared with the con- trol. However, in pigs treated with lead and montmo- riltonite nanocomposite in combination, the activity of δ-amino levulinic acid dehydratase was similar to con- trol pigs. Our results indicate that montmorillonite nanocomposite treatment of pigs exposed to lead re- suited in reduced lead concentrations in body tissues. It appears that montmorillonite nanocomposite func- tions by increasing fecal excretion of lead.

关键词： δ-amino levulinic acid dehydratase lead montmorillonite zinc protoporphyrin

An association study of HFEgene mutation with idiopathic male infertility in the Chinese Han population

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Asian journal of Andrology 2012年第4期14卷 599-603页

作者： Xiao-ying yu Bin-Bin Wang Zhong-Cheng Xin Tao Liu Ke Ma jian jiang Xiang Fang Li-Hua yu yi-Feng Peng Xu Ma Institute of Reproductive Medicine Yijishan HospitalWannan Medical CollegeWuhu 241001China National Research Institute for Family Planning Beijing 100081China peking Union Medical College Beijing 100081China Andrology Center Peking University First HospitalBeijing 100034China World Health Organization Collaborating Centre for Research in Human Reproduction Beijing 100081China

Mutations in the haemochromatosis gene （HFE） influence iron status in the general population of Northern Europe, and excess iron is associated with the impairment of spermatogenesis. The aim of this study is to investigate the association between three mutations （C282y, H63D and S65C） in the HFEgene with idiopathic male infertility in the Chinese Han population. Two groups of Chinese men were recruited： 444 infertile men （including 169 with idiopathic azoospermia） and 423 controls with proven fertility. The HFEgene was detected using polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） technique. The experimental results demonstrated that no C282y or $65C mutations were detected. Idiopathic male infertility was not significantly associated with heterozygous H63D mutation （odds ratio=O.801, 95% confidence interval=0.452-1.421, X2=0.577, P=0.448）. The H63D mutation frequency did not correlate significantly with the serum luteinizing hormone （LH）, follicle-stimulating hormone （FSH） and testosterone （T） levels in infertile men （P=0.896, P=0.404 and P=O.05, respectively）. Our data suggest that the HFEH63D mutation is not associated with idiopathic male reproductive dysfunction.

关键词： gene mutation gonadotropic hormone HFE male infertility

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非圆行星齿轮马达流场仿真分析

机床与液压 2024年第15期52卷 192-197页

作者：周如林黄园月赵志伟胡滨肖浩阳王煜袁晓明北京天玛智控科技股份有限公司北京101399 燕山大学河北省重型机械流体动力传输与控制实验室河北秦皇岛066004 燕山大学起重机械关键技术全国重点实验室河北秦皇岛066004

为了研究非圆行星齿轮内部流场特性,建立非圆行星齿轮马达的几何模型和有限元模型,并对模型进行仿真参数设置及网格无关性验证。对非圆行星齿轮马达进行流场仿真分析,探究油膜位置流场速度变化规律,研究入口压力为5~20 MPa时Q100型、Q16... 详细信息

为了研究非圆行星齿轮内部流场特性,建立非圆行星齿轮马达的几何模型和有限元模型,并对模型进行仿真参数设置及网格无关性验证。对非圆行星齿轮马达进行流场仿真分析,探究油膜位置流场速度变化规律,研究入口压力为5~20 MPa时Q100型、Q160型、Q250型非圆行星齿轮马达的流量及容积效率随压力的变化规律;此外针对Q250型非圆行星齿轮马达,探究油膜间隙分别为0.02、0.03、0.04 mm时的流量及容积效率随压力的变化规律。最后通过开展样机测试试验,验证仿真模型的准确性。结果表明:在相同的入口压力下,容积越大,容积效率越高;容积效率随着油膜间隙的增大而降低,当油膜间隙为0.02 mm、压力为5 MPa时,马达容积效率可达90.9%;试验和理论得到的容积效率与转矩关系曲线的变化趋势基本一致,最大误差仅为5.76%,验证了仿真模型的准确性。

关键词：非圆行星齿轮马达有限元分析流场仿真容积效率

单原子Al修饰空位缺陷V2C(MXene)对H_(2)气体表面吸附的第一性原理研究

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原子与分子物理学报 2024年第3期41卷 9-16页

作者：龚安稳胡梦晗曹宇刘莹曾勇谋莫瀚宁周晓龙梧州学院机械与资源工程学院梧州543002 广西大学资源环境与材料学院南宁530004 昆明理工大学材料科学与工程学院昆明650093

基于第一性原理计算方法,对含空位缺陷的V2C(MXene)在不同位点修饰单原子Al的相关性能进行系统研究.研究表明,几何优化后得到含空位缺陷的V2C稳定结构表面能为-3075.53 j/m2,单原子Al修饰本征V2C单原子的吸附能为1.5511eV、单原子Al修... 详细信息

基于第一性原理计算方法,对含空位缺陷的V2C(MXene)在不同位点修饰单原子Al的相关性能进行系统研究.研究表明,几何优化后得到含空位缺陷的V2C稳定结构表面能为-3075.53 j/m2,单原子Al修饰本征V2C单原子的吸附能为1.5511eV、单原子Al修饰空位缺陷V2C的吸附能为-2.0763 eV,这表明含空位缺陷的V2C,由于单原子Al的修饰可以明显改善晶体结构稳定性.进一步从态密度、分波态密度、吸氢能力研究发现,各体系态密度和分波态密度均出现分波越过费米能级的现象,表现出较强的金属性;V2C吸附H_(2)气体分子吸附能为-7.5867 eV,而空位缺陷V2C和单原子Al修饰空位缺陷V2C两个体系对H_(2)气体分子的吸附能仅为-0.9851 eV、-2.7130 eV,均未能进一步改善V2C对H_(2)气体分子的吸附性能,这对于储氢材料研发提供了一定的理论指导.

关键词： MXene V2C 空位缺陷单原子Al 吸附第一性原理

Effect of amphoteric Zn2+ on the determination of B2O3 content in glass

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Effect of amphoteric Zn2+ on the determination of B2O3 conte...