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瓦斯抽采钻孔孔周煤岩体损伤破坏试验

陕西煤炭 2024年第6期43卷 28-33,69页

作者：焦稳锋董亚楠易辉陕西陕煤黄陵矿业有限公司一号煤矿陕西延安727307

为研究瓦斯抽采钻孔蠕变失稳特性,采用数字散斑系统观测孔周煤岩体裂纹在扩展过程中的损伤破坏及蠕变过程,得到孔周煤岩体的损伤演化及蠕变力学特性规律。将煤样破坏分为缓慢型、间断型和瞬间破坏型,3个类型的煤样损伤破坏产生的裂隙主... 详细信息

为研究瓦斯抽采钻孔蠕变失稳特性,采用数字散斑系统观测孔周煤岩体裂纹在扩展过程中的损伤破坏及蠕变过程,得到孔周煤岩体的损伤演化及蠕变力学特性规律。将煤样破坏分为缓慢型、间断型和瞬间破坏型,3个类型的煤样损伤破坏产生的裂隙主要由沿x方向应变引起,其中在不同的发育阶段损伤累积增加导致裂隙发育程度也不同,最终形成了煤样表面的不同破坏类型。在恒载应力下,随着蠕变时间推移,煤岩体的变形能力、变形空间都逐渐减弱,映射了现场的孔周煤岩体的抗压抗变形能力与蠕变时间的关系。

关键词：瓦斯抽采孔周煤岩体损伤破坏蠕变特征裂隙演化

Near-surface wind speed changes in eastern China during 1970-2019 winter and its possible causes

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Advances in Climate Change Research 2022年第2期13卷 228-239页

作者： Xiao LI Qiao-Ping LI yi-hui DING Mei WANG Chinese Academy of Meteorological Sciences Beijing 100081China University of Chinese Academy of Sciences Beijing 100049China Shanghai Energy Technology Development Co. LtdShanghai 200233China Earth System Modeling and Prediction Centre China Meteorological AdministrationBeijing 100081China National Climate Center China Meteorological AdministrationBeijing 100081China Nanjing Joint Institute for Atmospheric Sciences Nanjing 210041China

The changes in near-surface wind speed(NWS)have a crucial influence on the wind power industry,and previous studies have indicated that NWS on global and China has declined continuously for decades under global ***,recently,the decreasing trend of global NWS has slowed down and even showed a recovery *** the observation data of 831 weather stations of the China Meteorological Administration and the Japanese 55-year reanalysis data from 1970 to 2019,NWS changes in eastern China were analyzed and the possible influencing factors were *** show that winter NWS presented a decreasing trend from−0.29 m s^(−1) per decade(p<0.001)in 1970-1989 to−0.05 m s^(−1) per decade(p<0.01)in ***,NWS exhibited a significant upward trend of 0.18 m s^(−1) per decade(p<0.1)in 2011-2019,resulting in a 19.6%per decade recovery of the wind power generation.A possible cause is asymmetric changes of the sea level pressure and near-surface air temperature differences between the mid-high latitudes(40°-60°N,80°-120°E)and low latitudes(20°-40°N,110°-140°E)altered the horizontal air pressure ***,NWS changes were closely associated with the large-scale ocean-atmosphere circulations(LOACs).NWS at 77.4%of the stations in eastern China shows significant correlation(p<0.05)with the East Asian winter monsoon index,besides,the inter/multidecadal variability of NWS was considerably correlated to four LOACs,including Arctic oscillation(AO),North Atlantic oscillation(NAO),Pacific decadal oscillation(PDO),and El Niño-Southern Oscillation(ENSO).The time-series reconstructed by a multiple linear regression model based on above five LOACs matches well with the *** variability of NWS were significantly correlated to AO(−0.45,p<0.01)and NAO(−0.28,p<0.05),while the correlation between NWS and ENSO was weak.

关键词： Near-surface wind speed Wind energy Wind speed recovery East Asian winter monsoon Large-scale ocean‒atmosphere circulations

Mixed nonlinear dynamic voltage phasor tracing method based on WAMS/SCADA

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第6期10卷 868-876页

作者： Xiao-gang CHEN Yong-hui yi Wei WANG Quan-yuan JIANG Chuang-xin GUO yi-jia CAO School of Electrical Engineering Zhejiang University Hangzhou 310027 China Hangzhou Electric Power Bureau Hangzhou 310009 China Zhejiang Provincial Electric Power Company Hangzhou 310007 China

By considering the static voltage characteristic of the load, we propose a WAMS/SCADA mixed nonlinear method to estimate the voltage of unobservable buses caused by topology change or phasor measurement unit (PMU) malfunction in a power system. By modeling the load characteristic with data from SCADA, we employed the Gauss-Seidel method to solve the nonlinear equations and estimate the voltage of unobservable buses with the high precision voltages of neighboring buses measured by a PMU. Simulations were carried out on the IEEE 39-bus system, and the results show that this novel method can dynamically and accurately trace the variation of the voltage phasor of the unobservable buses.

关键词： Wide area measurement system (WAMS) Supervisory control and data acquisition (SCADA) system Observability Dynamic tracing Nonlinear equation

Nptx2在阿尔茨海默病中通过抑制补体系统逆转小胶质细胞诱发突触损失的研究

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中国临床药理学杂志 2024年第16期40卷 2334-2338页

作者：谭辰熙刘洋邸辞寒许德超张会怡齐齐哈尔医学院附属第二医院神经内科黑龙江齐齐哈尔161000

目的在阿尔茨海默病(AD)模型中探究神经元正五聚蛋白Ⅱ(Nptx2)对补体系统、小胶质细胞活化和突触密度的影响。方法将6个月龄APPswe/PS1dE9双转基因C57BL/6小鼠分为模型组(脑室注射AAV-Veh 1×10^(10)GC)和模型+AAV-Nptx2组(脑室注射AAV-... 详细信息

目的在阿尔茨海默病(AD)模型中探究神经元正五聚蛋白Ⅱ(Nptx2)对补体系统、小胶质细胞活化和突触密度的影响。方法将6个月龄APPswe/PS1dE9双转基因C57BL/6小鼠分为模型组(脑室注射AAV-Veh 1×10^(10)GC)和模型+AAV-Nptx2组(脑室注射AAV-Nptx21×10^(10)GC),将同龄野生型C57BL/6小鼠分为对照组(脑室注射AAV-Veh 1×10^(10)GC)和对照+AAV-Nptx2组(脑室注射AAV-Nptx21×10^(10)GC),每组12只。给药1个月后,用Morris水迷宫法评估小鼠的认知功能,用蛋白质印迹法检测Nptx2与钙离子结合接头分子1(Iba1)蛋白的表达水平,用酶联免疫吸附试验法检测补体相关蛋白的含量,用高尔基体染色法评估突触可塑性。结果对照组、对照+AAV-Nptx2组、模型组和模型+AAV-Nptx2组的平台象限停留时间分别为(44.72±10.92)、(53.32±10.29)、(21.92±3.80)和(36.47±6.41)s,穿越平台次数分别为(10.08±2.64)、(9.58±3.09)、(2.25±1.29)和(5.92±1.38)次,Nptx2蛋白相对表达水平分别为0.33±0.06、0.63±0.10、0.09±0.03和0.57±0.22,Iba1蛋白相对表达水平分别为0.17±0.06、0.23±0.08、0.97±0.16与0.40±0.14,突触密度分别为22.75±4.27、29.25±4.78、8.25±2.99和23.75±4.86。模型组的上述指标与模型+AAV-Nptx2组和对照组比较,在统计学上差异均有统计学意义(均P<0.05)。结论Nptx2蛋白过表达可以抑制补体系统激活,降低小胶质细胞活化,增加突触密度,达到减轻AD小鼠认知功能损伤的作用。

关键词：神经元正五聚蛋白Ⅱ 阿尔茨海默病补体系统小胶质细胞突触

山东省羊源产气荚膜梭菌耐药性及分子遗传进化特征分析

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中国预防兽医学报 2024年第6期46卷 593-600页

作者：徐吉荣赵翠樊丽武健朱凤珠伊惠侯磊泰安市动物疫病预防控制中心山东泰安271000 肥城市畜牧兽医事业发展服务中心山东肥城271600

为了解山东省羊源产气荚膜梭菌的流行及耐药情况,本研究于2022年11月~2023年3月,从山东省泰安、济宁和菏泽地区的3个规模化养羊场采集150份新鲜粪便样品,从中共分离到43株产气荚膜梭菌,分离率为28.7%(43/150)。利用PCR方法扩增产气荚膜... 详细信息

为了解山东省羊源产气荚膜梭菌的流行及耐药情况,本研究于2022年11月~2023年3月,从山东省泰安、济宁和菏泽地区的3个规模化养羊场采集150份新鲜粪便样品,从中共分离到43株产气荚膜梭菌,分离率为28.7%(43/150)。利用PCR方法扩增产气荚膜梭菌分离株的毒素基因、耐药基因以及8对管家基因;利用K-B药敏纸片法检测分离菌的耐药性,并采用Fisher确切概率法统计分析分离株耐药表型与相应耐药基因之间的相关性。结果显示,产气荚膜梭菌分离株均携带cpa毒素基因,均为A型产气荚膜梭菌;对四环素和克林霉素耐药的菌株较多,分别占72.1%(31/43)和67.4%(29/43),对1~5种抗菌药耐药的菌株占2.3%~48.8%,多重耐药率为27.9%(12/43);四环素类耐药基因tetA(P)的检出率最高,为44.2%(19/43),其次为β-内酰胺类耐药基因blaCTX-M,检出率为27.9%(12/43);耐药表型和耐药基因的符合率在41.2%~100%;根据管家基因的PCR扩增结果利用多位点序列分型将43株产气荚膜梭菌分为23个ST序列型,其中ST1和ST22为主要的流行型。本研究结果为山东地区羊源产气荚膜梭菌的监测、相关疫病的防控及养殖场抗菌药的合理使用提供参考依据。

关键词：产气荚膜梭菌毒素分型药敏试验 MLST分型

A new construction for the statistical theory of the nonextensive systems

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Chinese Science Bulletin 2014年第21期59卷 2528-2533页

作者： hui-yi Tang Tie-Ling Song Jian-hui Wang Yong-Li Ma State Key Laboratory of Surface Physics and Department of Physics Fudan University Department of Physics Nanchang University

We propose a new statistical theory for classical and quantum small *** is a generalized scheme of the Boltzmann–Gibbs statistical theory by extending the Boltzmann–Gibbs statistical factor from infinite systems to finite systems based on the microcanonical ensemble distribution function and keeping this factor in all thermodynamic *** reconstruct the statistical theory for finite systems by obtaining the expression of the average particle number and the thermodynamic quantities such as entropy and specific heat,in the finite *** also explore the discontinuous phase transitions in the interacting classical nanoscale gases without the thermodynamic limit.

关键词：统计理论函数系统有限系统热力学极限量子体系玻耳兹曼热力过程热力学量

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甜椒幼苗低温胁迫的生理响应与转录组分析

福建农业科技 2024年第4期55卷 6-16页

作者：马馨怡林艺辉余松金倪辉林蔚韦幂陈汉鑫漳州市农业科学研究所福建漳州363005 集美大学海洋食品与生物工程学院福建厦门361021 福建省农业科学研究院亚热带农业研究所福建漳州363005

为了阐明甜椒响应低温胁迫的分子机制,对低温胁迫时甜椒幼苗的MDA含量、SOD活性以及光合作用相关参数进行了测定,并结合转录组测序分析。结果表明:低温胁迫3 d时甜椒MDA含量显著升高,SOD活性显著降低,光合相关参数显著下降;与低温处理... 详细信息

为了阐明甜椒响应低温胁迫的分子机制,对低温胁迫时甜椒幼苗的MDA含量、SOD活性以及光合作用相关参数进行了测定,并结合转录组测序分析。结果表明:低温胁迫3 d时甜椒MDA含量显著升高,SOD活性显著降低,光合相关参数显著下降;与低温处理前相比,转录组测序分析结果显示检测出差异基因主要涉及酶系统、光合作用、信号传导以及相关转录因子,其中SOD相关基因CaSOD呈示上调表达,光合作用关键基因CaCP4与CaHCR的表达量则显著下调。研究结果为深入解析甜椒幼苗响应低温胁迫的分子机制及甜椒抗低温育种奠定了基础。

关键词：甜椒低温胁迫转录组差异表达基因

Analytical Description for Solid-State Phase Transformation Kinetics:Extended Works from a Modular Model, a Review

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Journal of Materials Science & Technology 2016年第2期32卷 97-120页

作者： Feng Liu Kai Huang yi-hui Jiang Shao-Jie Song Bin Gu State Key Laboratory of Solidification Processing Northwestern Polytechnical University

Solid-state phase transformation plays an important role in adjusting the microstructure and thus tuning the properties of materials. A general modular, analytical model has been widely applied to describe the kinetics of solid-state phase transformation involving nucleation, growth and impingement; the basic conception for iso-kinetics which constitutes a physical foundation for the kinetic models or recipes can be extended by the analytical model. Applying the model, the evolution of kinetic parameters is an effective tool for describing the crystallization of enormous amorphous alloys. In order to further improve the effectiveness of this kinetic model, recently, the recipes and the model fitting procedures were extended, with more factors （e.g., anisotropic growth, soft impingement, and thermodynamic driving force） taken into consideration in the modified models. The recent development in the field of analytical model suggests that it is a general, flexible and open kinetic model for describing the solid-state phase transformation kinetics.

关键词： Phase transformation Nucleation Growth Kinetics Analytical model

MPC of distillation column with side reactors for methyl acetate

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Chinese Journal of Chemical Engineering 2017年第12期25卷 1798-1804页

作者： Cuimei Bo Jun Li Lei Yang hui yi Jihai Tang Xu Qiao College of Automation and Electrical Engineering Nanjing Tech University. Nanjing210009 China State Key Laboratory of Materials-oriented Chemical Engineering Nanjing Tech University Nanjing 210009 China

This paper focuses on the dynamic control of distillation column with side reactors(SRC) for methyl acetate production. To obtain the optimum integrated structure and steady state simulation, the systematic design approach based on the concept of independent reaction amount is applied to the process of SRC for methyl acetate production. In addition to the basic control loops, multi-variable model predictive control modular with methyl acetate concentration and temperature of sensitive plate is designed. Then, based on process simulation software Aspen Plus, dynamic simulation of SRC for methyl acetate production is used to verify the effectiveness of the control scheme.

关键词： Distillation column with side reactors (SRC) Multi-variable model predictive control (MPC) Methyl acetate Steady-state optimization Dynamic simulation