检索结果-南通市图书馆

Diagenesis of the Triassic Yanchang Formation Tight Sandstone Reservoir in the Xifeng–Ansai Area of Ordos Basin and its Porosity Evolution

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2016年第3期90卷 956-970页

作者： LIU Mingjie LIU Zhen WANG Peng pan gaofeng School of Geoscience and Technology Southwest Petroleum University State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing) Changqing Branch of Geophysical Research Institute BGP Inc.CNPC

This work aims to reveal the evolution of the porosity in the Triassic Yanchang Formation tight sandstone reservoir of the Xifeng-Ansai area of Ordos Basin. Based on destructive diagenesis （compaction and cementation） and constructive diagenesis （dissolution） of sandstone reservoirs, this study analyzed the diagenesis characteristics of the tight sandstone reservoirs in this area, and discussed the relationship between sandstone diagenesis and porosity evolution in combination with present porosity profile characteristics of sandstone reservoir. The effect simulation principle was employed for the mathematical derivation and simulation of the evolution of porosity in the Yanchang Formation tight sandstone reservoirs. The result shows that compaction always occurs in tight sandstone reservoirs in the Yanchang Formation, and cementation occurs when the burial depth increases to a certain value and remains ever since. Dissolution occurs only at a certain stage of the evolution with window features. In the corresponding present porosity profile, diagenesis is characterized by segmentation. From the shallow to the deep, compaction, compaction, cementation and dissolution, compaction and cementation occur successively. Therefore, the evolution of sandstone porosity can be divided into normal compaction section, acidification and incremental porosity section, and normal compaction section after dissolution. The results show that the evolution of sandstone porosity can be decomposed into porosity reduction model and porosity increase model. The superposition of the two models at the same depth in the three stages or in the same geological time can constitute the evolution simulation of the total porosity in sandstone reservoirs. By simulating the evolution of sandstone reservoir porosity of the eighth member in Xifeng area and the sixth member in Ansai area, it shows that they are similar in the evolution process and trend. The difference is caused by the regional uplift or subsidence and burial depth.

关键词： tight sandstone diagenesis porosity evolution effect simulation Yanchang Formation Ordos Basin

Impact of anthropogenic heat emissions on meteorological parameters and air quality in Beijing using a high-resolution model simulation

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2022年第4期16卷 47-57页

作者： Hengrui Tao Jia Xing gaofeng pan Jonathan Pleim Limei Ran Shuxiao Wang Xing Chang Guojing Li Fei Chen Junhua Li Aviation University of Air Force Changchun 130022China School of Environment and State Key Joint Laboratory of Environment Simulation and Pollution Control Tsinghua UniversityBeijing 100084China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China Research Triangle Park Environmental Protection AgencyNC 27711USA East Remote Sensing Laboratory United States Department of AgricultureNC 20250USA Unit No.96941 of Chinese People's Liberation Army Beijing 100041China Unit No.31010 of Chinese People's Liberation Army Beijing 100081China

Anthropogenic heat emissions(AHE)play an important role in modulating the atmospheric thermodynamic and kinetic properties within the urban planetary boundary layer,particularly in densely populated megacities like Beijing.In this study,we estimate the AHE by using a Large-scale Urban Consumption of energY(LUCY)model and further couple LUCY with a high-resolution regional chemical transport model to evaluate the impact of AHE on atmospheric environment in Beijing.In areas with high AHE,the 2-m temperature(T_(2))increased to varying degrees and showed distinct diurnal and seasonal variations with maxima in night and winter.The increase in 10-m wind speed(WS_(10))and planetary boundary layer height(PBLH)exhibited slight diurnal variations but showed significant seasonal variations.Further,the systematic continuous precipitation increased by 2.1 mm due to the increase in PBLH and water vapor in upper air.In contrast,the precipitation in local thermal convective showers increased little because of the limited water vapor.Meanwhile,the PM_(2.5) reduced in areas with high AHE because of the increase in WS_(10) and PBLH and continued to reduce as the pollution levels increased.In contrast,in areas where prevailing wind direction was opposite to that of thermal circulation caused by AHE,the WS_(10) reduced,leading to increased PM_(2.5).The changes of PM_(2.5) illustrated that a reasonable AHE scheme might be an effective means to improve the performance of PM_(2.5) simulation.Besides,high AHE aggravated the O_(3) pollution in urban areas due to the reduction in NO_(x).

关键词： Anthropogenic heat emissions LUCY High-resolution Meteorological parameters Air quality

Secrecy outage analysis for underlay cognitive radio networks over correlated channels

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2017年第2期60卷 107-115页

作者： Jiliang ZHANG Hui ZHAO gaofeng pan Chongqing Key Laboratory of Nonlinear Circuits and Intelligent Information Processing School of Electronic and Information Engineering Southwest University

This paper investigates the secrecy outage performance of underlay cognitive radio networks, in which a source in a secondary system transmits its confidential information to a legitimate destination in the presence of an eavesdropper. Specifically, the main(the source-to-destination) and eavesdropping(the sourceto-eavesdropper) channels are assumed to be correlated. Moreover, it is also assumed that the main channel and the channel from the source to the primary user's receiver are correlated. Tight closed-form analytical expression for secrecy outage probability and the closed-form analytical expression for the probability of non-zero secrecy capacity are derived and validated by simulation results when the interference temperature limit is comparably large.

关键词： cognitive radio networks correlated fading channels probability of non-zero secrecy capacity secrecy outage probability

Secure analysis over generalized-K channels

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2020年第4期63卷 242-244页

作者： Luyao ZHANG Hui ZHAO gaofeng pan Liang YANG Jiawei CHEN School of Mathematics and Statistics Southwest University Computer Electrical and Mathematical Science and Engineering DivisionKing Abdullah University of Science and Technology School of Information and Electronics Beijing Institute of Technology College of Computer Science and Electronic Engineering Hunan University

Dear editor,The secrecy outage probability (SOP) is used to estimate the secrecy outage performance when the transmitter has no state information about potential wiretap channels [1], i.e., silent eavesdropping. Most previous work, such as [2, 3], has focused on the SOP defined in [1], which we call the conventional SOP in this study, where both un-

关键词： SOP Secure analysis over generalized-K channels

Schisandrin B protects PC12 cells by decreasing the expression of amyloid precursor protein and vacuolar protein sorting 35

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2012年第9期7卷 652-658页

作者： Mingmin Yan Shanping Mao Huimin Dong Baohui Liu Qian Zhang gaofeng pan Zhiping Fu Department of Neurology Renmin Hospital Wuhan University Wuhan 430060 Hubei Province China Department of Neurosurgery Renmin Hospital Wuhan University Wuhan 430060 Hubei Province China

PC12 cell injury was induced using 20 μM amyloid β-protein 25-35 to establish a model of Alzheimer＇s disease. The cells were then treated with 5, 10, and 25 μM Schisandrin B. Methylthiazolyldiphenyl-tetrazolium bromide assays and Hoechst 33342 staining results showed that with increasing Schisandrin B concentration, the survival rate of PC12 cells injured by amyloid β-protein 25-35 gradually increased and the rate of apoptosis gradually decreased. Reverse transcription-PCR, immunocytochemical staining and western blot results showed that with increasing Schisandrin B concentration, the mRNA and protein expression of vacuolar protein sorting 35 and amyloid precursor protein were gradually decreased. Vacuolar protein sorting 35 and amyloid precursor protein showed a consistent trend for change. These findings suggest that 5, 10, and 25 μM Schisandrin B antagonizes the cellular injury induced by amyloid β-protein 25-35 in a dose-dependent manner. This may be caused by decreasing the expression of vacuolar protein sorting 35 and amyloid precursor protein.

关键词： Schisandrin B PC12 cells amyloid β-protein 25-35 amyloid precursor protein vacuolar protein sorting 35 neural protection

Physical-layer secrecy outage of spectrum sharing CR systems over fading channels

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2016年第10期59卷 112-120页

作者： Hequn LIU Hui ZHAO Hong JIANG Chaoqing TANG gaofeng pan Tingting LI Yunfei CHEN Chongqing Key Laboratory of Nonlinear Circuits and Intelligent Information Processing Southwest University School of Mathematics and Statistics Southwest University School of Engineering University of Warwick

In this paper, we investigate the physical-layer secrecy outage performance of underlay spectrum sharing systems over Rayleigh and log-normal fading channels in the presence of one eavesdropper. In particular, the secondary transmitter sends data to the legitimate receiver under the constraints of the interference temperature at the primary receiver, while suffering the wiretap from the eavesdropper. Closed-form and approximated expressions are derived for the secrecy outage probability over Rayleigh and log-normal fading channels,respectively. The accuracy of our performance analysis is verified by simulation results.

关键词： spectrum sharing cognitive radio secrecy outage probability Rayleigh fading channels log-normal fading channels

A throughput aware with collision-free MAC for wireless LANs

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2016年第2期59卷 240-242页

作者： Tingrui PEI Yafeng DENG Zhetao LI Gengming ZHU gaofeng pan Youngjune CHOI Hiroo SEKIYA College of Information Engineering Xiangtan University Key Laboratory of Intelligent Computing & Information Processing of Ministry of Education Xiangtan University School of Computer Science & Engineering Hunan University of Science and Technology School of Electronic and Information Engineering Southwest University Department of Information and Computer Engineering Ajou University Graduate School of Advanced Integration Science Chiba University

Dear editor,The Carrier Sense Multiple Access with Collision Avoidance(CSMA/CA)hybrid with the resource reservation approach from Time Division Multiple Address(TDMA)has been emerged as a promising method to solve collision problems in wireless LANs[1–6].In the hybrid method,a TDMA circle contains multiple slots for nodes to contend for the channel.Furthermore,it allows a

关键词： MAC CSCF free TDMA A throughput aware with collision-free MAC for wireless LANs

FAST馈源支撑钢索及舱索连接锚具役后剩余承载力研究

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

清华大学学报（自然科学版） 2022年第11期62卷 1758-1763,1779页

作者：李庆伟李辉姜鹏姚蕊潘高峰中国科学院国家天文台北京100101 中国科学院FAST重点实验室北京100101

500m口径球面射电望远镜(five-hundred-meter aperture spherical radio telescope,FAST)的馈源支撑系统是一个跨度巨大的柔索牵引并联机构,馈源舱由6根并联的钢索悬挂于空中,并随着6根钢索的同步收放在反射面上方大范围内缓慢运动。为... 详细信息

500m口径球面射电望远镜(five-hundred-meter aperture spherical radio telescope,FAST)的馈源支撑系统是一个跨度巨大的柔索牵引并联机构,馈源舱由6根并联的钢索悬挂于空中,并随着6根钢索的同步收放在反射面上方大范围内缓慢运动。为研究到达服役年限后FAST馈源支撑钢索及舱索连接锚具的剩余承载力,该文对达到5年设计使用年限后的FAST馈源支撑钢索及舱索连接锚具进行了破断拉伸强度、拉伸疲劳试验。结果表明:在运行5年后,馈源支撑钢索及舱索连接锚具仍有足够的剩余承载力继续服役。该研究为今后馈源支撑钢索在适当的监测手段辅助下增加服役时间提供了试验依据。

关键词： FAST馈源支撑钢索破断拉伸试验拉伸疲劳试验剩余承载力

金属有机凝胶限域CdS QDs异质结光催化剂协同降解诺氟沙星和还原Cr(Ⅵ)

在线全文

学校读者我要写书评

暂无评论

复合材料学报 2023年第5期40卷 2847-2858页

作者：计海峰刘书亭石洪飞潘高峰吉林化工学院石油化工学院吉林132000

构建具有高效电荷转移途径的异质结材料是光催化降解水体复合污染物的关键。采用凝胶限域法将CdS量子点(CdS QDs)分散在金属有机凝胶MOX(Al)中,制备出CdS QDs@MOX(Al)异质结光催化剂。通过XRD、TEM、XPS、N2吸附-脱附等温曲线、UV-Vis ... 详细信息

构建具有高效电荷转移途径的异质结材料是光催化降解水体复合污染物的关键。采用凝胶限域法将CdS量子点(CdS QDs)分散在金属有机凝胶MOX(Al)中,制备出CdS QDs@MOX(Al)异质结光催化剂。通过XRD、TEM、XPS、N2吸附-脱附等温曲线、UV-Vis DRS、瞬态光电流(TPC)响应和电化学阻抗谱(EIS)等手段对样品的组成结构和界面电荷传输效率进行了表征及分析,并探讨了在可见光下协同降解诺氟沙星(NF)和还原Cr(Ⅵ)的催化活性和机制。结果表明:1.0-CdS QDs@MOX(Al)对NF/Cr(Ⅵ)复合污染物体系表现出优异的光催化活性,降解过程符合伪一级动力学模型,表观速率常数k分别是纯MOX(Al)和CdS的6.1(8.5)倍和5.3(3.5)倍。与单一污染物体系相比,CdS QDs@MOX(Al)对NF/Cr(Ⅵ)复合污染物体系的光催化效率显著提高。活性物种捕获实验证实h^(+)和·O_(2)^(−)为主要活性物种,光催化活性的增强主要归因于MOX(Al)和CdS QDs间形成的Type-Ⅱ型异质结构,加速了光生电荷在异质结构界面处的有效分离和转移。

关键词：金属有机凝胶 CdS QDs 光催化异质结催化剂机制