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The influence of pore structure on P-& S-wave velocities in complex carbonate reservoirs with secondary storage space 被引量:10
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作者 Wang Haiyang Sam Zandong Sun +3 位作者 Yang Haijun Gao Hongliang Xiao Youjun Hu Hongru 《Petroleum Science》 SCIE CAS CSCD 2011年第4期394-405,共12页
Secondary storage spaces with very complex geometries are well developed in Ordovician carbonate reservoirs in the Tarim Basin,which is taken as a study case in this paper.It is still not clear how the secondary stora... Secondary storage spaces with very complex geometries are well developed in Ordovician carbonate reservoirs in the Tarim Basin,which is taken as a study case in this paper.It is still not clear how the secondary storage space shape influences the P-& S-wave velocities (or elastic properties) in complex carbonate reservoirs.In this paper,three classical rock physics models (Wyllie timeaverage equation,Gassmann equation and the Kuster-Toks z model) are comparably analyzed for their construction principles and actual velocity prediction results,aiming at determining the most favourable rock physics model to consider the influence of secondary storage space shape.Then relationships between the P-& S-wave velocities in carbonate reservoirs and geometric shapes of secondary storage spaces are discussed from different aspects based on actual well data by employing the favourable rock physics model.To explain the influence of secondary storage space shape on V P-V S relationship,it is analyzed for the differences of S-wave velocities between derived from common empirical relationships (including Castagna's mud rock line and Greenberg-Castagna V P-V S relationship) and predicted by the rock physics model.We advocate that V P-V S relationship for complex carbonate reservoirs should be built for different storage space types.For the carbonate reservoirs in the Tarim Basin,the V P-V S relationships for fractured,fractured-cavernous,and fractured-hole-vuggy reservoirs are respectively built on the basis of velocity prediction and secondary storage space type determination.Through the discussion above,it is expected that the velocity prediction and the V P-V S relationships for complex carbonate reservoirs should fully consider the influence of secondary storage space shape,thus providing more reasonable constraints for prestack inversion,further building a foundation for realizing carbonate reservoir prediction and fluid prediction. 展开更多
关键词 Complex carbonate reservoir secondary storage space velocity prediction v p-v S relationships
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Preparation of cross-linked magnetic chitosan with quaternary ammonium and its application for Cr(Ⅵ) and P(Ⅴ) removal 被引量:9
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作者 Wei Yao Pinhua Rao +2 位作者 Irene M.C.Lo Wenqi Zhang Wenrui Zheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第12期2379-2386,共8页
Pollutants that exist in anionic species are issues of concern in water treatment. Compared to cationic pollutants, the removal of anionic pollutants by adsorption is more difficult because most adsorbents carry predo... Pollutants that exist in anionic species are issues of concern in water treatment. Compared to cationic pollutants, the removal of anionic pollutants by adsorption is more difficult because most adsorbents carry predominantly negative charges in neutral and alkaline environments. In this study, a cross-linked chitosan derivative with quaternary ammonium and magnetic properties(QM-chitosan) was prepared and employed to remove chromium(VI) and phosphorus(V)(Cr(VI) and P(V)) from aqueous environments. The QM-chitosan was characterized by Fourier transform infrared spectrometry(FT-IR),thermogravimetric analysis(TGA), energy dispersive X-ray(SEM-EDX) and zeta potential.Batch experiments show that QM-chitosan can effectively remove Cr(VI) and P(V), and the main mechanism was believed to be electrostatic interaction. A pseudosecond-order model was fitted to describe the kinetic processes of Cr(VI) and P(V) removal. The adsorption isotherms of both Cr(VI) and P(V) on the QM-chitosan were well fitted by the Langmuir isotherm equation. The saturated adsorption capacity of P(V)(2.783 mmol/g) was found to be higher than that of Cr(VI)(2.323 mmol/g), resulting from the size of the H2PO-4ions being smaller than that of the HCr O-4ions. However, the theoretical calculation and experimental results showed that QM-chitosan had a stronger affinity for Cr(VI) than P(V). The adsorption–desorption of the QM-chitosan was evaluated, and high regeneration rates were demonstrated. 展开更多
关键词 Magnetic chitosan Quaternary ammonium Cr(vI) pv ADSORpTION
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杂环化合物氨氧化法制备杂环芳腈研究Ⅰ.3-甲基吡啶氨氧化法制备烟腈 被引量:6
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作者 喻鹏 黄驰 +1 位作者 李晓芸 郑穹 《武汉大学学报(理学版)》 CAS CSCD 北大核心 2003年第2期179-182,共4页
对 3 甲基吡啶经氨氧化法制备重要的精细化学品烟腈进行了研究 ,初步筛选到高效实用的Z697号催化剂 .考察了催化剂组成和反应条件对 3 甲基吡啶的转化率、烟腈的产率 (摩尔 )及选择性、反应产物的组分及含量的影响 .在合适的条件下 ,... 对 3 甲基吡啶经氨氧化法制备重要的精细化学品烟腈进行了研究 ,初步筛选到高效实用的Z697号催化剂 .考察了催化剂组成和反应条件对 3 甲基吡啶的转化率、烟腈的产率 (摩尔 )及选择性、反应产物的组分及含量的影响 .在合适的条件下 ,3 甲基吡啶转化率为 10 0 % ,烟腈的产率为 85 .2 % ,产物纯度大于 99% ,并经元素分析。 展开更多
关键词 杂环化合物 3-甲基吡啶 杂环芳腈 烟腈 氨氧化法 制备 催化剂 反应条件 产率
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载铁活性炭的制备及对水中P(V)的吸附性能研究 被引量:5
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作者 卫志宏 吕兴菊 王正芳 《昆明理工大学学报(自然科学版)》 CAS 北大核心 2012年第2期72-77,87,共7页
通过直接蒸发法制备载铁活性炭,研究了载铁活性炭对水中P(V)的吸附等温线和吸附热动力学,并分析了pH值、P(V)初始浓度等因素对载铁活性炭吸附性能的影响.实验表明,载铁活性炭可以有效快速地吸附P(V),载铁活性炭对P(V)的去除效果随pH值... 通过直接蒸发法制备载铁活性炭,研究了载铁活性炭对水中P(V)的吸附等温线和吸附热动力学,并分析了pH值、P(V)初始浓度等因素对载铁活性炭吸附性能的影响.实验表明,载铁活性炭可以有效快速地吸附P(V),载铁活性炭对P(V)的去除效果随pH值的上升、P(V)初始浓度的增大而降低.吸附等温线符合Langmuir方程,最大吸附量为9.32 mg/g;准二级动力学能够很好地描述P(V)在载铁活性炭上的吸附行为,吸附速率常数在0.01 min.g/mg左右,且随着温度的升高逐渐增大.吸附P(V)的活化能Ea为10.89 kJ/mol,吸附行为是自发吸热的化学吸附过程. 展开更多
关键词 载铁活性炭 p(v) 吸附 动力学 热力学
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急性呼吸窘迫综合征犬低容积段的压力-容积曲线 被引量:4
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作者 盛华 朱蕾 +3 位作者 徐云洁 蔡映云 朱惠莉 钮善福 《中华结核和呼吸杂志》 CAS CSCD 北大核心 2005年第11期797-799,共3页
关键词 急性呼吸窘迫综合征(ARDS) 压力-容积曲线 p-v 实验研
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用p-V图讨论理想气体直线过程的直观方法 被引量:4
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作者 沈仲达 《物理与工程》 1993年第3期25-28,共4页
本文用 p-V 图清楚直观地表示了理想气体直线过程中的温度最高点M 和吸放热转折点 N 的物理含义,方法简单直观,学生易于接受。
关键词 p-v 直观方法 末态 物理含义 工科物理 初态 减函数 点对应 直观表示 对应点
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一维光束整形系统仿真及实验技术研究 被引量:3
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作者 张宇碟 王刚 +3 位作者 王文涛 于铭 王超 唐晓军 《激光与红外》 CAS CSCD 北大核心 2014年第11期1248-1252,共5页
针对高功率板条激光放大系统光束整形的需要,基于CODE V软件对一维光束整形系统进行仿真,光束整形方向输出光光学传递函数接近衍射极限。光束整形方向视场0.5 mrad时,引入波像差为0.105λ。利用四波剪切干涉仪测量He-Ne光以及光纤种子... 针对高功率板条激光放大系统光束整形的需要,基于CODE V软件对一维光束整形系统进行仿真,光束整形方向输出光光学传递函数接近衍射极限。光束整形方向视场0.5 mrad时,引入波像差为0.105λ。利用四波剪切干涉仪测量He-Ne光以及光纤种子光整形后波前,P-V值变化小于0.25λ,RMS变化小于0.05λ。 展开更多
关键词 DpSSL 光束整形 波像差 p-v RMS
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二维光束整形系统设计与仿真 被引量:2
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作者 于陶然 王超 +2 位作者 张宇碟 刘洋 唐晓军 《激光与红外》 CAS CSCD 北大核心 2015年第11期1360-1363,共4页
针对高功率板条激光波前矫正的需要,基于ZEMAX软件对二维光束扩束整形系统进行设计和仿真。系统将初始尺寸为2.5 mm×28 mm,发散角为7 mrad×2 mrad矩形光束扩束整形为尺寸为40 mm×40.2 mm,发散角为0.54 mrad×1.3 mra... 针对高功率板条激光波前矫正的需要,基于ZEMAX软件对二维光束扩束整形系统进行设计和仿真。系统将初始尺寸为2.5 mm×28 mm,发散角为7 mrad×2 mrad矩形光束扩束整形为尺寸为40 mm×40.2 mm,发散角为0.54 mrad×1.3 mrad的方形光束。光束整形方向输出光学传递函数接近衍射极限,光束整形方向视场10 mrad时,两方向引入波像差之和为0.0186λ,P-V值小于0.1λ。 展开更多
关键词 二维光束扩束整形 光学传递函数 p-v
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Derivation of Martin-Hou Equation of State from Hard-particle Perturbation Theory 被引量:2
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作者 ZHANG Bing-jian (Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. China) HOU Yu-chun (Department of Chemical Engineering, Zhejiang University, Hangzhou 310027, P. R. China) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2000年第1期49-56,共8页
In this paper, the Martin-Hou equation of state is derived by using a power series representation of radial distribution function and an analytic representation of multi-section potential based on the Barker-Henderso... In this paper, the Martin-Hou equation of state is derived by using a power series representation of radial distribution function and an analytic representation of multi-section potential based on the Barker-Henderson hard-particle perturbation theory including high-order terms. In the derivation, a theoretical form of Martin-Hou equation was obtained. It had a similar form and the same capability to predict P-V-T properties as the Martin-Hou equation and no additional data were required for evaluating the constants. The characteristic constants of the theoretical expression have certain relationships with the molecular parameters. 展开更多
关键词 perturbation theory Martin-Hou equation of state Theoretical expression p-v-T properties Molecular parameter
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Evaluation of Pt and Au pressure scales based on MgO absolute pressure scale 被引量:2
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作者 WU ZhongQing LIN Feng 《Science China Earth Sciences》 SCIE EI CAS CSCD 2017年第1期114-123,共10页
The equations of state(EOSs)of MgO produced by two independent scale-free methods,(1)the simultaneous elastic wave velocity and in situ synchrotron X-ray measurements(Kono et al.,2010;Li et al.,2006)and(2)the first-pr... The equations of state(EOSs)of MgO produced by two independent scale-free methods,(1)the simultaneous elastic wave velocity and in situ synchrotron X-ray measurements(Kono et al.,2010;Li et al.,2006)and(2)the first-principles calculations(Wu et al.,2008),agree well with each other to at least 150 GPa and 2000 K.Furthermore,the EOS from first-principles calculations also agrees well with shock wave data,another pressure-scale-free data.These agreements strongly support that these EOSs provide reliable absolute pressure scales.Here we evaluate Au and Pt EOSs based on the EOS of Wu et al.(2008)using the simultaneously measured volume data of MgO,Au,and Pt from the literature.The primary pressure scales developed by Tange et al.(2009)and Yokoo et al.(2009)using only pressure-scale-free experimental data of MgO,Au,and Pt produce internal consistent pressure and agree with EOS of Wu et al.(2008).The Au EOS by Tsuchiya(2003)works well at room temperature but underestimates pressure at high temperature.The Au EOS by Fei et al.(2007)can well describe thermal pressure.The EOSs of Pt by Holmes et al.(1989)and Ono et al.(2011)work well at both room temperature and high temperature.The results also suggest that the discrepancy between bulk modulus of iron from experiments(Mao et al.,1990)and those from Earth's core(Dziewonski and Anderson,1981)is not originated from the overestimation of pressure by the EOS of Holmes et al.(1989).At high pressure and temperature,pressure uncertainty resulted from volume error becomes similarly important as the accuracy of the pressure scale. 展开更多
关键词 p-v relation ab initio calculation pressure standard Clapeyron slope
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P-V criticality and Joule-Thomson expansion of charged AdS black holes in the Rastall gravity 被引量:2
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作者 Yuan Meng Jin Pu Qing-Quan Jiang 《Chinese Physics C》 SCIE CAS CSCD 2020年第6期176-181,共6页
We discuss the P-V criticality and the Joule-Thomson expansion of charged AdS black holes in the Rastall gravity. We find that although the equation-of-state of a charged AdS black hole in the Rastall gravity is relat... We discuss the P-V criticality and the Joule-Thomson expansion of charged AdS black holes in the Rastall gravity. We find that although the equation-of-state of a charged AdS black hole in the Rastall gravity is related to the Rastall parameter λ, its reduced equation-of-state at the critical point is independent of the Rastall parameter λ, as is the case in the Einstein gravity where λ=0. This is the reason why the critical exponents are not related to the Rastall parameter λ. We also find that the inversion temperature Ti is related to the Rastall parameter λ,but that the minimum inversion temperature Timin and the ratio ε between the minimum inversion temperature and the critical temperature are both independent of the Rastall parameter λ. At the critical point, the thermodynamic evolution of a charged AdS black hole in the Rastall gravity behaves as in the van der Waals fluid and charged AdS black hole in the Einstein gravity. We show the inversion curves and isenthalpic curves in the T-P plane and analyze the effect of the Rastall constant λ on the inversion curves of a charged AdS black hole during the Joule-Thomson expansion. 展开更多
关键词 p-v criticality Joule-Thomson expansion AdS black hole Rastall gravity
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TiO2-Fe3O4-ATP吸附剂对P(V)的吸附动力学和热力学 被引量:1
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作者 刘彪 杨净 +1 位作者 薛田田 苏可心 《材料保护》 CAS CSCD 北大核心 2020年第8期68-73,共6页
为提高凹凸棒黏土的吸附能力,将凹凸棒黏土负载纳米二氧化钛制成复合吸附剂,通过TiO2-Fe3O4-ATP吸附剂对P(V)的静态吸附试验,对其动力学特征、吸附平衡和热力学参数进行了研究,探讨了其吸附机理。结果表明:复合吸附剂对P(V)有良好的吸... 为提高凹凸棒黏土的吸附能力,将凹凸棒黏土负载纳米二氧化钛制成复合吸附剂,通过TiO2-Fe3O4-ATP吸附剂对P(V)的静态吸附试验,对其动力学特征、吸附平衡和热力学参数进行了研究,探讨了其吸附机理。结果表明:复合吸附剂对P(V)有良好的吸附作用,吸附过程可用准二级反应动力学模型描述,吸附过程主要受颗粒扩散(PDC)和化学反应(CRD)两方面控制。吸附类型符合Freundlich吸附模型,吸附热力学参数ΔG为-1.83^-0.92 kJ/mol,ΔS=-45.89 kJ/mol,ΔH=-15.18 kJ/mol,吸附是自发、熵减、放热的过程。 展开更多
关键词 凹凸棒黏土 纳米二氧化钛 p(v) 吸附 动力学 热力学
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A theoretical form of the Martin-Hou equation of state 被引量:1
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作者 张秉坚 侯虞钧 《Science China Chemistry》 SCIE EI CAS 1999年第1期89-95,共7页
A new equation of state is derived from the Barker-Henderson hard-sphere perturbation theory. It has the form similar to the Martin-Hou equation of state. The numerical values of the characteristic constants in the eq... A new equation of state is derived from the Barker-Henderson hard-sphere perturbation theory. It has the form similar to the Martin-Hou equation of state. The numerical values of the characteristic constants in the equation can be calculatrd by the method of Martin and Hou. The equation can he used to predictP-V-T properties accurately for fluids when the critical parameters (Tc,Pc, and Vc) and one point on the vapor pressure cure are given. By using the functional relationships between the characteristic constants and the microscopic parameters, the molecular microscopic parameters of the substance can be obtained. 展开更多
关键词 statistical mechanics pERTURBATION theory Martin-Hou equation of state p-v-T properties molecular MICROSCOpIC parameters.
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The Stability of the Gauss-Laguerre Rule for Cauchy P.V. Integrals on the Half Line
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作者 Maria Rosaria Capobianco Giuliana Criscuolo 《American Journal of Computational Mathematics》 2023年第4期505-511,共7页
In this paper, the authors give a different and more precise analysis of the stability of the classical Gauss-Laguerre quadrature rule for the Cauchy P.V. integrals on the half line. Moreover, in order to obtain this ... In this paper, the authors give a different and more precise analysis of the stability of the classical Gauss-Laguerre quadrature rule for the Cauchy P.V. integrals on the half line. Moreover, in order to obtain this result they give some new estimates for the distance of the zeros of the Laguerre polynomials that can be useful also in other contests. 展开更多
关键词 Gauss Quadrature Exponential Weights Cauchy p.v. Integrals Stability
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Performance and Efficiency Simulation Study of a Smart-Grid Connected Photovoltaic System
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作者 Warsame H. Ali Penrose Cofie +2 位作者 John H. Fuller Savitha Lokesh Emmanuel S. Kolawole 《Energy and Power Engineering》 2017年第2期71-85,共15页
The availability of non-renewable energy sources such as crude oil, natural gas, coal etc., is fast diminishing. So the renewable energy sources such as solar, hydropower, geothermal, wind, tidal energy, are gaining m... The availability of non-renewable energy sources such as crude oil, natural gas, coal etc., is fast diminishing. So the renewable energy sources such as solar, hydropower, geothermal, wind, tidal energy, are gaining more and more importance. Many new developments to convert these renewable energy sources into usable forms are taking place. Most renewable energy sources are used to produce electricity. In this paper, a performance and efficiency simulation study of a smart-grid connected photovoltaic system using Chroma DC programmable power supply, AC programmable source and an Aurora Inverter is proposed. The simulation is performed in MATLAB environment where the Current-Voltage (I-V) and Power-Voltage (P-V) curves from the solar array simulator are generated and plotted. The proposed topology has been verified with satisfactory results. In addition, temperature and irradiance effects on I-V and P-V characteristic curves are verified. Also, the efficiency curves of the photovoltaic grid interface inverter are generated in the study. The MATLAB code developed in this paper is a valuable tool for design engineers comparing different inverters, calculating the optimum efficiency of a given inverter type. 展开更多
关键词 Smart-Grid photovoltaic System RENEWABLE and of Non-Renewable Energy CURRENT-vOLTAGE (I-v) and power-voltage (p-v) CURvES Inverter Electricity
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电感耦合等离子体原子发射光谱法测定中、低铬合金中硅、磷、钒的含量 被引量:1
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作者 陈淑云 林建农 +1 位作者 余景明 邵志刚 《宽厚板》 2016年第5期18-20,共3页
采用电感耦合等离子体原子发射光谱法(ICP-AES)快速分析中、低铬合金中Si、P、V的含量,实验开发出独特的溶样方法,快速溶解难溶铬铁合金,被测定元素无挥发损失.利用标准曲线法定量,元素测定值的相对标准偏差(n=6)在0.24%-2.63%之间... 采用电感耦合等离子体原子发射光谱法(ICP-AES)快速分析中、低铬合金中Si、P、V的含量,实验开发出独特的溶样方法,快速溶解难溶铬铁合金,被测定元素无挥发损失.利用标准曲线法定量,元素测定值的相对标准偏差(n=6)在0.24%-2.63%之间.结果表明:应用该方法分析铬铁标准样品,测定值和认定值相符. 展开更多
关键词 电感耦合等离子体原子发射光谱法 低铬合金 硅磷钒
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Pitzer三参数通用关系式的改进 被引量:1
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作者 蒋登高 杨志平 《化学工程》 CAS CSCD 北大核心 1990年第1期70-72,69,共4页
针对Pitzer三参数通用关系式的局限性,本文提出了一个新的较简便的方程式。对19种物质140个状态点的检验表明,该方程式不仅应用范围较宽,而且精确度也比Pitzer三参数通用关系式,Die(?)erici方程,R-K方程和Berthelot方程高。
关键词 pitzer 渗数关系式 流体 p-v-T
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色素绒毛结节性滑膜炎的诊断 被引量:1
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作者 朱建民 《实用癌症杂志》 1989年第3期219-220,共2页
色素绒毛结节性滑膜炎(pigmented villo-nodullar synovitis简称P.V.S)是滑膜增殖性疾病。1852年Chassaignai首先报告手指屈指肌腱滑膜结节性病变,1864年Simon首先报告膝关节局限性色素绒毛结节性滑膜炎(localized pigmented villonodul... 色素绒毛结节性滑膜炎(pigmented villo-nodullar synovitis简称P.V.S)是滑膜增殖性疾病。1852年Chassaignai首先报告手指屈指肌腱滑膜结节性病变,1864年Simon首先报告膝关节局限性色素绒毛结节性滑膜炎(localized pigmented villonodullar synovitis,简称L.P.V.S)1909年Moser首先报告膝关节弥漫性色素绒毛结节性滑膜炎(diffuse pigmented vlllonodu-lar Synovitis,简称D.P.V.S)。1912年Dowd最先提出P.V.S是恶性肿瘤,1941年Jaffe等提出P.V.S是一种良性滑膜瘤(1),1984年Rao和Vig-orita提出P.V.S是滑膜纤维母细胞和组织细胞的一种肿瘤性增殖(2). 展开更多
关键词 滑膜炎 p.v.S. X线检查
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p.V.T.t法气体流量标准装置
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作者 王鹏 张永胜 赵玉婷 《计测技术》 2021年第2期159-166,共8页
为了满足高准确度气体流量计的量值传递需求,建立了一套p.V.T.t法气体流量标准装置,该装置由标准容器、温度传感器、压力传感器、标准流量积算仪等部分组成,工作时气体经过音速喷嘴充入标准容器,根据标准容器容积、充气时间及充气前后... 为了满足高准确度气体流量计的量值传递需求,建立了一套p.V.T.t法气体流量标准装置,该装置由标准容器、温度传感器、压力传感器、标准流量积算仪等部分组成,工作时气体经过音速喷嘴充入标准容器,根据标准容器容积、充气时间及充气前后的压力、温度计算气体流量。该装置工作压力范围为0~0.6 MPa,流量范围为0.5~1000 m^(3)/h,扩展不确定度为0.1%(k=2),有效提升了本单位气体流量最高标准的准确性,增强了量值传递能力。 展开更多
关键词 p.v.T.t 气体流量 正压 常压 不确定度
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关于P、V操作的新理解
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作者 杨淑群 《抚州师专学报》 2002年第2期55-58,共4页
P、V操作的概念及使用在操作系统中非常重要,这里从一些新颖的角度来分析P、V操作,用P、V操作来实现进程的同步与互斥以及以一种简易易行的逻辑关系则可以解决P操作嵌套时P操作的执行次序.
关键词 v操作 同步 互斥 信号量 缓冲器 逻辑关系 操作系统 并发进程 p操作
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