检索结果-南通市图书馆

Further discussion of CO_(2) huff-n-puff mechanisms in tight oil reservoirs based on NMR monitored fluids spatial distributions

引用

Petroleum Science 2023年第1期20卷 350-361页

作者： Wei-Yu tang James J.sheng Ting-Xue jiang Unconventional Petroleum Research Institute China University of PetroleumBeijing102249China Bob L.Herd Department of Petroleum Engineering Texas Tech UniversityLubbockTX79409USA Sinopec Research Institute of Petroleum Engineering Beijing100101China

Due to the poor physical properties of tight reservoirs,CO_(2) huff-n-puff(HNP)is considered a potential enhanced oil recovery(EOR)method after primary *** plays a critical role in the effective implementation of CO_(2) *** the optimization requires a good understanding of the EOR *** this work,the spatial distribution of oil saturation under different experimental conditions was analyzed by the NMR method to further discuss the HNP *** to the variation of 1D frequency signal amplitude,we divided the core into the hardly movable area and movable area,the region with the obvious signal decline was defined as the movable area,and the hardly movable area was the region with limited signal *** on that the recovery characteristics of different scenarios were ***,the necessity of the soaking stage was studied,where three scenarios with different soaking times were carried ***,the injection pressure was adjusted to investigate the effect of the pressure *** T_(2) spectra show that soaking has significantly improved the production of crude oil in small pores,and higher oil recovery in a single cycle is observed,but it is lower when the elapsed time(total operation time)is the same.31.03% of oil can be recovered after 3 cycles HNP,which increases to 33.8% and 37.06% for the 4 cycles and 6 cycles *** the pressure gradient increases,more oil is removed out of the matrix,and the oil in the deep part of the reservoir can be effectively *** the CO_(2) huff-n-puff process,the oil distributions are similar to the solution gas drive,the residual oil is distributed at the close end of the core and the range that the oil can be efficiently recovered is limited.

关键词： Tight reservoirs Low-field nuclear magnetic resonance (NMR) CO_(2)huff-n-puff Enhanced oil recovery

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

肠外营养致肝功能异常的主动监测和危险因素分析

引用

中南药学 2024年第3期22卷 575-579页

作者：游利江唐密密邓晟南华大学附属第二医院临床药学科湖南衡阳421001 中南大学湘雅医院药学部长沙410008 国家老年疾病临床医学研究中心(湘雅医院) 长沙410008

目的探索肠外营养所致肝功能异常在胃肠道恶性肿瘤患者中的发生率、临床特点及危险因素,降低临床用药风险。方法通过中国医院药物警戒系统(CHPS)搜索2022年7月1日—12月31日在南华大学附属第二医院使用肠外营养治疗的胃肠道恶性肿瘤患者... 详细信息

目的探索肠外营养所致肝功能异常在胃肠道恶性肿瘤患者中的发生率、临床特点及危险因素,降低临床用药风险。方法通过中国医院药物警戒系统(CHPS)搜索2022年7月1日—12月31日在南华大学附属第二医院使用肠外营养治疗的胃肠道恶性肿瘤患者,病例组为CHPS中触发警报信号指示肝功能异常且经药师审核的患者,在未触发警报信号的患者中,剔除重复入院患者得到对照组,分析肝功能异常的发生情况,采用二元Logistic回归分析筛选潜在风险因素。结果肠外营养所致肝功能异常在胃肠道恶性肿瘤患者的发生率为4.98%;85%发生在用药后5~10 d,以轻度转氨酶升高为主要表现。二元Logistic回归分析显示败血症、合并脂肪乳是肠外营养致肝功能异常的独立危险因素(P<0.05)。结论本研究通过CHPS开展药品不良反应主动监测,可反映肠外营养所致肝功能异常在胃肠道恶性肿瘤患者的发生情况,为临床安全用药提供参考。

关键词：肠外营养肝功能异常主动监测中国医院药物警戒系统

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Microstructure Distribution and Tensile Anisotropy of Dissimilar Friction Stir Welded AM60 and AZ31 Magnesium Alloys

引用

Acta Metallurgica Sinica(English Letters) 2020年第11期33卷 1487-1504页

作者： Jun-Lei Zhang Han Liu Yu-Lu Xie Guang-sheng Huang xiang Chen Bin jiang Ai-Taotang Fu-sheng Pan State Key Laboratory of Mechanical Transmission College of Materials Science and EngineeringChongqing UniversityChongqing 400044China National Engineering Research Center for Mg Alloys Chongqing UniversityChongqing 400044China

The microstructure distribution,tensile anisotropy and fracture behaviors in the dissimilar friction stir welded joint of AM60/AZ31 alloys were *** results showed that a significant grain refinement and an orientation fluctuation occurred in the *** grain size of AZ31 side in joint was obviously smaller than that of AM60 *** was a higher percentage of low angle grain boundaries(LAGBs)and a lower degree of recrystallization in AZ31 side compared with those in AM60 side,especially for the thermo-mechanically affected zone in AZ31 *** discrepancies of grain size distribution,recrystallization behavior and LAGBs in joint depended on the different initial state of two metals and the inhomogeneous temperature distribution in *** addition,the(0001)basal plane in weld was roughly parallel to the surface of the pin,showing the symmetrically distributed texture *** joint showed an obvious tensile anisotropy due to the special texture *** comprehensive tensile properties of joint along the three directions decreased in the order:welding direction,45°direction and transverse *** maximum ultimate tensile strength,yield strength and elongation of the joint were 242 MPa,116 MPa and 21.2%,*** fluctuations of grain size and texture in joint affected the fracture behavior of samples in the three directions.

关键词： Friction stir welding Dissimilar joint Texture Anisotropy Tensile properties

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Direction-of-Arrival Method Based on Randomize-Then-Optimize Approach

引用

Journal of Electronic Science and Technology 2022年第4期20卷 416-424页

作者： Cai-Yi tang sheng Peng Zhi-Qin Zhao Bo jiang Science and Technology on Electronic Information Control Laboratory Chengdu 610036 School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731 54th Research Institute of china Electronics Technology Group Shijiazhuang 050081

The direction-of-arrival(DOA)estimation problem can be solved by the methods based on sparse Bayesian learning(SBL).To assure the accuracy,SBL needs massive amounts of snapshots which may lead to a huge computational *** order to reduce the snapshot number and computational complexity,a randomize-then-optimize(RTO)algorithm based DOA estimation method is ***“learning”process for updating hyperparameters in SBL can be avoided by using the optimization and Metropolis-Hastings process in the RTO *** apply the RTO algorithm for a Laplace prior,a prior transformation technique is *** demonstrate the effectiveness of the proposed method,several simulations are proceeded,which verifies that the proposed method has better accuracy with 1 snapshot and shorter processing time than conventional compressive sensing(CS)based DOA methods.

关键词： Compressive sensing(CS) randomize-then-optimize(RTO) single snapshot sparse signal reconstruction

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Genetic Diversity Based on Allozyme Alleles of Chinese Cultivated Rice

引用

Agricultural Sciences in china 2007年第6期6卷 641-646页

作者： tang sheng-xiang WEI Xing-hua jiang Yun-zhu D S Brar G SKhush State Key Laboratory of Rice Biology China National Rice Research Institute Hangzhou 310006 P.R.China International Rice Research Institute Manila Philippines

Genetic diversity was analyzed with 6 632 core rice cultivars selected from 60 282 Chinese rice accessions on the basis of 12 allozyme loci, Pgil, Pgi2, Amp1, Amp2, Amp3, Amp4, Sdhl, Adhl, Estl, Est2, Est5 and Est9, by starch gel electrophoresis. Among the materials examined, 52 alleles at 12 polymorphic loci were identified, which occupied 96.3% of 54 alleles found in cultivated germplasm of O. sativa L. The number of alleles per locus ranged from 2 to 7 with an average of 4.33. The gene diversity （He） each locus varied considerably from 0.017 for Amp4 to 0.583 for Est2 with an average gene diversity （Ht） 0.271, mid Shannon-Wiener index from 0.055 to 0.946 with an average of 0.468. The degree of polymorphism （DP） was in a range from 0.9 to 46.9% with an average of 21.4%. It was found that the genetic diversity in japonica （Keng） subspecies was lower in terms of allele＇s number, Ht and S-W index, being 91.8, 66.2 and 75.7% of indica （Hsien） one, respectively. Significant genetic differentiation between indica and japonica rice has been appeared in the loci Pgil, Amp2, Pgi2, and Est2, with higher average coefficient of genetic differentiation （Gst） 0.635, 0.626, 0.322 and 0.282, respectively. Except less allele number per locus （3.33） for modern cultivars, being 76.9% of landraces, the Ht and S-W index showed in similar between the modem cultivars and the landraces detected. In terms of allozyme, the rice cultivars in the Southwest Plateau and Central china have richer genetic diversity. The present study reveals again that Chinese cultivated rice germplasm has rich genetic diversity, showed by the allozyme allele variation.

关键词： cultivated rice allozyme analysis genetic diversity genetic differentiation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

In-beam gamma rays of CSNS Back-n characterized by black resonance filter

引用

NUCLEAR SCIENCE AND TECHNIQUES 2024年第10期35卷 1-12页

作者： Wang, Jin-Cheng Ren, Jie jiang, Wei Ruan, Xi-Chao Liu, Ying-Yi Yang, Hao-Lan Xu, Kuo-Zhi Pan, Xin-Yi Sun, Qi Bao, Jie Huang, Han-Xiong Bai, Hao-Fan Bai, jiang-Bo Cao, Ping Chen, Qi-Ping Chen, Yong-Hao Duan, Wen-Hao Fan, An-Chuan Fan, Rui-Rui Feng, Chang-Qing Gu, Min-Hao Han, Chang-Cai Han, Zi-Jie He, Guo-Zhu He, Yong-Cheng Hong, Yang Hu, Yi-Wei jiang, Zhi-Jie Kang, Ling Lan, Chang-Lin Li, Bo Li, Feng Li, Qiang Li, Xiao Li, Yang Liu, Jie Liu, Rong Liu, Shu-Bin Liu, Yi-Na Luan, Guang-Yuan Ning, Chang-Jun Qiu, Yi-Jia Ren, Wen-Kai Ren, Zhi-Zhou Song, Zhao-Hui Sun, Kang Tan, Zhi-Xin tang, Jing-Yu tang, sheng-Da Wang, Li-Jiao Wang, Peng-Cheng Wang, Zhao-Hui Wen, Zhong-Wei Wu, Xiao-Guang Wu, Xuan Wu, Ze-Peng Xia, Cong Xie, Li-Kun Yi, Han Yu, Tao Yu, Yong-Ji Zhang, Guo-Hui Zhang, Hang-Chang Zhang, Qi-Wei Zhang, Xian-Peng Zhang, Yu-Liang Zhang, Zhi-Yong Zhao, Mao-Yuan Zhou, Zhi-Hao Zhu, Ke-Jun Zou, Chong china Inst Atom Energy Key Lab Nucl Data Beijing 102413 Peoples R China Chinese Acad Sci Inst High Energy Phys Beijing 100049 Peoples R China Spallat Neutron Source Sci Ctr Dongguan 523803 Peoples R China Chinese Acad Sci Inst High Energy Phys State Key Lab Particle Detect & Elect Beijing 100049 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China Peking Univ Sch Phys State Key Lab Nucl Phys & Technol Beijing 100871 Peoples R China Fudan Univ Inst Modern Phys Shanghai 200433 Peoples R China Univ Sci & Technol china State Key Lab Particle Detect & Elect Hefei 230026 Peoples R China Univ Sci & Technol china Sch Nucl Sci & Technol Hefei 230026 Peoples R China Univ Sci & Technol china Dept Modern Phys Hefei 230026 Peoples R China china Acad Engn Phys Inst Nucl Phys & Chem Mianyang 621900 Peoples R China Univ Sci & Technol china USTC Archaeometry Lab Hefei 230026 Peoples R China Northwest Inst Nucl Technol Xian 710024 Peoples R China Lanzhou Univ Sch Nucl Sci & Technol Lanzhou 730000 Peoples R China Univ Sci & Technol china Inst Adv Technol Hefei 230027 Peoples R China

The back-streaming white-neutron beamline (Back-n) of the china Spallation Neutron Source is an essential neutron- research platform built for the study of nuclear data, neutron physics, and neutron applications. Many types of cross-sectional neutron-reaction measurements have been performed at Back-n since early 2018. These measurements have shown that a significant number of gamma rays can be transmitted to the experimental stations of Back-n along with the neutron beam. These gamma rays, commonly referred to as in-beam gamma rays, can induce a non-negligible experimental background in neutron-reaction measurements. Studying the characteristics of in-beam gamma rays is important for understanding the experimental background. However, measuring in-beam gamma rays is challenging because most gamma-ray detectors are sensitive to neutrons; thus, discriminating between neutron-induced signals and those from in-beam gamma rays is difficult. In this study, we propose the use of the black resonance filter method and a CeBr3 scintillation detector to measure the characteristics of the in-beam gamma rays of Back-n. Four types of black resonance filters, Ta-181, Co-59, Ag-nat, and Cd-nat, were used in this measurement. The time-of-flight (TOF) technique was used to select the detector signals remaining in the absorption region of the TOF spectra, which were mainly induced by in-beam gamma rays. The energy distribution and flux of the in-beam gamma rays of Back-n were determined by analyzing the deposited energy spectra of the CeBr3 scintillation detector and using Monte Carlo simulations. Based on the results of this study, the background contributions from in-beam gamma rays in neutron-reaction measurements at Back-n can be reasonably evaluated, which is beneficial for enhancing both the experimental methodology and data analysis.

关键词： In-beam gamma rays Back-n Black filter resonance technique In-beam gamma rays Back-n CeBr3 scintillator Black filter resonance technique C6D6 DETECTOR SYSTEM LINE

来源：

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

Spectral Characteristics of White Organic Light-emitting Diodes Based on Novel Phosphorescent Sensitizer

引用

Chinese Journal of Chemical Physics 2008年第6期21卷 510-514页

作者： Xiao-qing tang Jun-sheng Yu Lu Li Wen Wen Ya-dong jiang State Key Laboratory of Electronic Thin Films and Integrated Devices School of Optoelectronic Information University of Electronic Science and Technology of China Chengdu 610054 China

White organic light-emitting diodes were fabricated by using a novel phosphorescence bis（1,2-diphenyl-1H-benzoimidazole）iridium（acetylacetonate）[（pbi）2Ir（acac）] as sensitizer and a fluorescent dye of 4- （dicyanomethylene）-2-t-butyl-6-（1,1,7,7-tetramethyljulolidyl-9-enyl）-4H-pyran （DCJTB） codoped into a carbazole polymer of poly（N-vinylcarbazole）（PVK）. Through characterizing the UV-Vis absorption spectra, the photoluminescence spectra of （pbi）2Ir（acac） and DCJTB, and the electroluminescence spectral properties of the WOLEDs, the energy transfer mechanisms of the codoped polymer system were deduced. The results demonstrate that the luminescent spectra with different intensity of （pbi）2Ir（acac） and DCJTB were co-existent in the EL spectra of the blended system, which is ascribed to an incomplete energy transfer process in the EL process. The efficient Forster and Dexter energy transfer between the host and the guests enabled a strong yellow emission from （pbi）2Ir（acac） and DCJTB, where （pbi）2Ir（acac） plays an important role as a phosphorescent sensitizer for DCJTB. With the blue emitting-layer of N,N＇-diphenyl-N,N＇-bis（1- naphthyl）（1,1＇-biphenyl）-4,4＇-diamine, the codoped system device achieved white emission. The codoped system showed that its Commissions Internationale de 1＇Eclairage coordinates were more independent of the variation of bias voltage than those of phosphorescent doped PVK systems.

关键词： White organic light-emitting diode Phosphorescent sensitizer Spectrum analysis

来源：

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

基于冬小麦高光谱图像的天然气微泄漏胁迫区域提取

引用

光谱学与光谱分析 2024年第3期44卷 770-776页

作者：李辉刘姁升蒋金豹陈绪慧张帅唐珂赵新伟杜兴强玉龙飞雪中国四维测绘技术有限公司北京100086 鄂尔多斯应用技术学院内蒙古鄂尔多斯017000 中国矿业大学(北京)地球科学与测绘工程学院北京100083 生态环境部卫星环境应用中心北京100094 中国资源卫星应用中心北京100094

天然气在能源结构中逐渐占据重要地位。由于天然气管道和储气库常年埋藏于地下,无氧腐蚀、自然灾害、注入井和管道口松懈等因素会导致气体发生泄漏。在地下储存天然气大规模泄漏之前确定泄漏点的位置并做出早期判断和预警十分必要。以... 详细信息

天然气在能源结构中逐渐占据重要地位。由于天然气管道和储气库常年埋藏于地下,无氧腐蚀、自然灾害、注入井和管道口松懈等因素会导致气体发生泄漏。在地下储存天然气大规模泄漏之前确定泄漏点的位置并做出早期判断和预警十分必要。以冬小麦为研究对象,采集4期高光谱图像数据,融合其图像、空间、时相特征,探寻天然气胁迫下冬小麦胁迫范围半径和时长之间的关系,并间接探测天然气微泄露点。一方面对连续统去除后的冬小麦高光谱图像数据进行连续小波变换并利用CWT_(mexh)指数[CWT_(mexh)=CW_(770)^(2)/(1-CW_(487))×CW_(550)]对高光谱胁迫组图像进行微泄露点信息提取,另一方面提取高光谱图像数据的PCA特征,基于SVM分类器提取天然气胁迫区域。最后将天然气微泄露识别结果进行数学形态学分析,并利用最小二乘对胁迫区域进行圆曲线拟合,探索天然气泄漏胁迫半径与胁迫天数的关系。结果表明:(1)CWT_(mexh)指数应用到成像高光谱数据表现出较好的识别性能;(2)SVM分类器可基于光谱差异性特征识别冬小麦胁迫区域,分类精度较好,最大分类精度可以达到99.25%,Kappa系数为0.97,且识别精度随天然气胁迫持续而增加;(3)冬小麦受胁迫区域半径和通气天数呈现强烈的线性相关。因此,结果表明,在冠层尺度和低空尺度通过高光谱遥感监测地表植被间接识别天然气微泄漏点具有可行性,可以预测地下天然气微泄漏随着时间变化引起的胁迫区域变化。该工作为星载高光谱遥感监测地下储存天然气泄漏点提供科学依据,为以后的工程应用提供技术支持。

关键词：天然气微泄漏冬小麦高光谱图像空间特征

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Polarized hydroxyapatite/BaTiO_(3) scaffolds with bio-inspired porous structure for enhanced bone penetration

引用

Rare Metals 2022年第1期41卷 67-77页

作者： Chun-sheng Shao Liang-Jian Chen Rui-Min tang Bo Zhang jiang-Jie tang Wei-Na Ma Department of Stomatology Third Xiangya HospitalCentral South UniversityChangsha 410013China

The porous HA/BaTiO_(3)ceramics have the potential to exhibit superior capabilities to promote bone ***,there are few reports on in vivo ***,we fabricated bio-inspired porous HA/BaTiO_(3)composites for bone repair via *** composites had a unique microstructure composed of the central canal and radically distributed lamellae,similar to the structure of nature cortical bone unite,the Haversian *** and non-polarized bio-inspired porous HA/BaTiO_(3)samples were implanted into the femoral condyle of the New Zealand *** was demonstrated that the polarization of the porous HA/BaTiO_(3)played a favorable part in bone ***,the combination between the osteoconductivity of the microstructure and augmented osteogenic cell behavior induced by charges on surfaces of polarized porous HA/BaTiO_(3)facilitated bone penetration through the *** bio-inspired porous HA/BaTiO_(3)composites are demonstrated to be promising scaffolds for bone repair.

关键词： Porous materials Freeze-casting Hydroxyapatite BaTiO_(3) Bone regeneration

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Degradation and biological performance of porous osteomimetic biphasic calcium phosphate in vitro and in vivo

引用

Rare Metals 2022年第2期41卷 457-468页

作者： Chun-sheng Shao Liang-Jian Chen Rui-Min tang Bo Zhang jiang-Jie tang Wei-Na Ma Department of Stomatology Third Xiangya HospitalCentral South UniversityChangsha 410013China

The combination between biphasic calcium phosphate(BCP)and the osteomimetic porous microstructure obtained via freeze casting is hoped to achieve excellent bone regeneration,while the effects of HA and b-TCP ratio changes on the degradation and biological performance of the BCP scaffolds with this unique microstructure need to be ***,we prepared the osteomimetic BCP scaffolds with different HA/b-TCP ratios(HA30/b-TCP70,HA50/b-TCP50,HA70/b-TCP30)and the effects of different HA/b-TCPHA/b-TCP ratios on the degradation and biological performance were studied in vitro and *** BCP scaffolds with different HA/b-TCP ratios exhibited similar microstructure,mechanical performance,and protein absorption capability,while HA70/b-TCP30 BCP scaffolds showed an advisable degradation *** in vitro confirmed the bio-compatibility and promotion on the proliferation,differentiation of MG63 cells in the porous osteomimetic BCP scaffolds with a HA/b-TCP ratio at 30:*** experiments also showed that the porous osteomimetic BCP scaffolds with a HA/b-TCP ratio at 30:70 had excellent bone regeneration capacity and proper degradation rate compatible with bone *** results reveal that the porous osteomimetic BCP scaffold with a HA/b-TCP ratio at 30:70 is a potential candidate of biodegradable bone substitutes used for bone repair.

关键词： Porous scaffolds Biphasic calcium phosphate Hydroxyapatite b-TCP Degradation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：