检索结果-南通市图书馆

A fast amplitude preserving three-parameter 3D parabolic Radon transform and its application on multiple attenuation

引用

Petroleum Science 2025年第1期22卷 163-177页

作者： Ji-Tao Ma Kai-ge zhao Zhen Liao College of geophysics China University of Petroleum (Beijing) State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing) CNPC Key Laboratory of geophysical Prospecting China University of Petroleum (Beijing)

Seismic wavefields propagate through three-dimensional(3D) space, and their precise characterization is crucial for understanding subsurface structures. Traditional 2D algorithms, due to their limitations, are insufficient to fully represent three-dimensional wavefields. The classic 3D Radon transform algorithm assumes that the wavefield's propagation characteristics are consistent in all directions, which often does not hold true in complex underground media. To address this issue, we present an improved 3D threeparameter Radon algorithm that considers the wavefield variation with azimuth and provides a more accurate wavefield description. However, introducing new parameters to describe the azimuthal variation also poses computational challenges. The new Radon transform operator involves five variables and cannot be simply decomposed into small matrices for efficient computation; instead, it requires large matrix multiplication and inversion operations, significantly increasing the computational load. To overcome this challenge, we have integrated the curvature and frequency parameters, simplifying all frequency operators to the same, thereby significantly improving computation efficiency. Furthermore,existing transform algorithms neglect the lateral variation of seismic amplitudes, leading to discrepancies between the estimated multiples and those in the data. To enhance the amplitude preservation of the algorithm, we employ orthogonal polynomial fitting to capture the amplitude spatial variation in 3D seismic data. Combining these improvements, we propose a fast, amplitude-preserving, 3D threeparameter Radon transform algorithm. This algorithm not only enhances computational efficiency while maintaining the original wavefield characteristics, but also improves the representation of seismic data by increasing amplitude fidelity. We validated the algorithm in multiple attenuation using both synthetic and real seismic data. The results demonstrate that the new algor

关键词： Three-parameter 3D Radon Orthogonal polynomial Amplitude-preserving Multiple attenuation

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Numerical simulation of microstructure and microporosity morphology in directional solidification of aluminum-copper alloys:Effect of copper content and withdrawal rate

引用

China Foundry 2025年第1期22卷 33-44页

作者： Wei Yuan hai-dong zhao Xu Shen Chun Zou Yuan Liu Qing-yan Xu National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640China Key Laboratory for Advanced Materials Processing Technology(Ministry of Education) Tsinghua UniversityBeijing 100084China

Microporosity formed in the solidification process of Al alloys is detrimental to the alloy properties.A two-dimensional cellular automaton(CA)model was developed to simulate the microstructure and microporosity formation in Al-Cu alloys,considering variations in Cu content and solidification *** results indicate that the Cu content primarily influences the growth of *** validate the model,directional solidification experiments were conducted on Al-Cu alloys with varing Cu contents and withdrawal *** experimental results of dendrites and microporosity characteristics agree well with the predictions from the developed model,thus confirming the validity of the *** alloy’s liquidus temperature,dendrite morphology,and hydrogen saturation solubility arising from different Cu contents have significant effects on microporosity *** withdrawal rate primarily affects the nucleation of hydrogen microporosity by altering cooling rates and dendritic growth rates,resulting in different microporosity characteristics.

关键词： microporosity dendrites cellular automaton Al-Cu alloys directional solidification

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

Direct seawater splitting for hydrogen production:Recent advances in materials synthesis and technological innovation

引用

Green Energy & Environment 2025年第1期10卷 11-33页

作者： Yilin zhao Zhipeng Yu Aimin ge Lujia Liu Joaquim Luis Faria Guiyin Xu Meifang Zhu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Center for Advanced Low-dimension MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai201620China International Iberian Nanotechnology Laboratory(INL) Avenida Mestre Jose VeigaBraga4715-330Portugal The MacDiarmid Institute for Advanced Materials and Nanotechnology School of Chemical and Physical SciencesVictoria University of WellingtonWellington6012New Zealand LSRE-LCM-Laboratory of Separation and Reaction Engineering-Laboratory of Catalysis and Materials Faculty of EngineeringUniversity of PortoRua Dr.Roberto Frias s/nPorto4200-465Portugal ALiCE-Associate Laboratory in Chemical Engineering Faculty of EngineeringUniversity of PortoRua Dr.Roberto Frias s/nPorto4200-465Portugal

Direct seawater splitting has emerged as a popular and promising research direction for synthesising clean,green,non-polluting,and sustainable hydrogen energy without depending on high-purity water in the face of the world’s shortage of fossil ***,efficient seawater splitting is hindered by slow kinetics caused by the ultra-low conductivity and the presence of bacteria,microorganisms,and stray ions in ***,producing hydrogen on an industrial scale is challenging due to the high production *** present review addresses these challenges from the catalyst point of view,namely,that designing catalysts with high catalytic activity and stability can directly affect the rate and effect of seawater *** the ion transfer perspective,designing membranes can block harmful ions,improving the stability of seawater *** the energy point of view,mixed seawater systems and self-powered systems also provide new and low-energy research systems for seawater ***,ideas and directions for further research on direct seawater splitting in the future are pointed out,with the aim of achieving low-cost and high-efficiency hydrogen production.

关键词： Seawater splitting Catalyst Membranes Mixed seawater systems Self-powered systems

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

Prediction of Short-Term Mortality after Valve Surgery： A Single Center＇s Perspective

引用

Chinese Medical Journal 2018年第20期131卷 2499-2502页

作者： Liang-Wei Chen Jie Chen Jun-Nan Zheng Yi-Ni Ke Qi-Feng Zhu Yi-Ming Ni hai-ge zhao Department of Thoracic and Cardiovascular Surgery First Affiliated Hospital of Zhejiang University Hangzhou Zhejiang 310003 China Department of Gastroenterology First Affiliated Hospital of Zhejiang University Hangzhou Zhejiang 310003 China Department of Cardiology Second Affiliated Hospital of Zhejiang University Hangzhou Zhejiang 310009 China

To the Editor： Valve stenosis and regurgitation can lead to a series of symptoms, including chest distress and dyspnea. Valve replacement is an effective surgical procedure that improves patients＇ quality of life and life span and has played an increasingly important role in treating mitral valve diseases. Previous studies have reported different risk factors and independent predictors of increased mortality in patients with mitral valve replacement （MVR） and/or aortic valve replacement （AVR）. This study retrospectively reviewed data on patients undergoing valve surgery to determine the risk factors and predictors of short-term mortality in this patient population.

关键词：

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

Comparisons of{100}texture improvement and formability in hot-rolled non-oriented electrical steel by austenite-ferrite phase transformation and shear deformation

引用

Journal of Iron and Steel Research International 2025年第1期32卷 171-185页

作者： Chi-hao Yu Hong-jiang Pan Yan-ping zhao De-ting Tang hai-jun Wang Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming650093YunnanChina School of Electronics and Information Engineering Anshun UniversityAnshun561000GuizhouChina School of Metallurgical Engineering Anhui University of TechnologyMa’anshan243032AnhuiChina

Over the years,the high magnetic induction of industrial Mn-added electrical steel is assumed to be the enhancement of{100}texture derived from its austenite-ferrite phase transformation during hot rolling(phase transformation(PT)method).However,it is still undetermined without straightforward experimental *** reason for{100}texture improvement of Mn-added electrical steel is experimentally confirmed due to the recrystallization induced by the austenite-ferrite phase transformation during hot ***,a more promising methodology to further improve{100}texture and formability of hot-rolled electrical steel is promoted by the control of hot rolling deformation condition(shear deformation(SD)method).The results show that the nucleation mechanisms of{100}oriented recrystallized grains are different in the samples by SD and PT methods,which are in-depth shear deformation and austenite-ferrite phase transformation,*** this case,coarse{100}oriented recrystallized grains and low residual stress are obtained in the sample by SD method,which is responsible for its superior{100}texture and *** contrast,the sample by PT method forms fine recrystallized grains with random orientations and accumulates severe residual stress.

关键词： Non-oriented electrical steel {100}texture Formability Austenite-ferrite phase transformation Shear deformation

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

Lifetime measurements in 138Nd

引用

Nuclear Science and Techniques 2021年第10期32卷 72-78页

作者： Jian Zhong Xiao-Guang Wu Shi-Peng Hu Ying-Jun Ma Yun Zheng Cong-Bo Li Guang-Sheng Li Bao-Ji Zhu Tian-Xiao Li Yan-Jun Jin Yan-Xiang Gao Qi-Wen Fan Ke-Yan Ma Dong Yang Hui-Bin Sun hai-ge zhao Lin Gan Qi Luo Zheng-Xin Wu College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China China Institute of Atomic Energy Beijing 102413China College of Physics Jilin UniversityChangchun 621010China

Lifetimes of the 2_(1)^(+),4_(1)^(+),7_(2)^(-),10_(2)^(+),12_(2)^(+),and 14_(1)^(+) states in 138 Nd populated via the 123 Sb(19 F,4n)138 Nd fusion–evaporation reaction were measured with the recoil distance Doppler shift technique in combination with the differential decay curve *** B(E2;2_(1)^(+)→0_(1)^(+))value fit well with the systematic trend in the Nd isotope chain and Grodzins rule,which proved that 138Nd is a transitional nucleus.

关键词： Lifetime measurement Recoil distance Doppler shift technique Differential decay curve method

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

Enhanced autophagic clearance of amyloid-βvia histone deacetylase 6-mediated V-ATPase assembly and lysosomal acidification protects against Alzheimer's disease in vitro and in vivo

引用

Neural Regeneration Research 2025年第9期20卷 2633-2644页

作者： Zhimin Long Chuanhua ge Yueyang zhao Yuanjie Liu Qinghua Zeng Qing Tang Zhifang Dong Guiqiong He Institute of Neuroscience School of Basic Medical SciencesChongqing Medical UniversityChongqingChina Department of Anatomy Chongqing Medical UniversityChongqingChina Department of Physiology Chongqing Medical UniversityChongqingChina Pediatric Research Institute Children’s Hospital of Chongqing Medical UniversityChongqingChina Ministry of Education Key Laboratory of Child Development and Disorders Children’s Hospital of Chongqing Medical UniversityChongqingChina National Clinical Research Center for Child Health and Disorders Children’s Hospital of Chongqing Medical UniversityChongqingChina Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders Children’s Hospital of Chongqing Medical UniversityChongqingChina

Recent studies have suggested that abnormal acidification of lysosomes induces autophagic accumulation of amyloid-βin neurons,which is a key step in senile plaque ***,resto ring normal lysosomal function and rebalancing lysosomal acidification in neurons in the brain may be a new treatment strategy for Alzheimer's *** acetylation/deacetylation plays a central role in lysosomal ***,we show that inhibiting the classic microtubule deacetylase histone deacetylase 6 with an histone deacetylase 6 shRNA or thehistone deacetylase 6 inhibitor valproic acid promoted lysosomal reacidification by modulating V-ATPase assembly in Alzheimer's *** rthermore,we found that treatment with valproic acid markedly enhanced *** clearance of amyloid-βaggregates,and ameliorated cognitive deficits in a mouse model of Alzheimer's *** findings demonstrate a previously unknown neuroprotective mechanism in Alzheimer's disease,in which histone deacetylase 6 inhibition by valproic acid increases V-ATPase assembly and lysosomal acidification.

关键词： Alzheimer's disease amyloid-β APP/PS1 mice autophagy cognitive impairment histone deacetylase 6 lysosomal acidification microtubule acetylation valproic acid V-ATPase

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

Integrating well logs, 3D seismic, and earthquake data for comprehensive prediction of 3D in-situ stress orientations: A case study from the Weiyuan area in the Sichuan Basin, China

引用

Petroleum Science 2025年第1期22卷 210-221页

作者： Huan Cao Yang zhao hai-Chao Chen Le-Le Zhang Cheng-Gang Xian Ji-Dong Yang Lu Liu State Key Laboratory of Petroleum Resources and Engineering and Unconventional Petroleum Research Institute China University of Petroleum (Beijing) Department of geophysics China University of Petroleum (East China) Aramco Beijing Research Center Aramco Asia

Determining the orientation of in-situ stresses is crucial for various geoscience and engineering applications. Conventional methods for estimating these stress orientations often depend on focal mechanism solutions(FMSs) derived from earthquake data and formation micro-imager(FMI) data from well ***, these techniques can be costly, depth-inaccurate, and may lack spatial coverage. To address this issue, we introduce the use of three-dimensional(3D) seismic data(active sources) as a lateral constraint to approximate the 3D stress orientation field. Recognizing that both stress and fracture patterns are closely related to seismic velocity anisotropy, we derive the orientation of azimuthal anisotropy from multi-azimuth 3D seismic data to compensate for the lack of spatial stress orientation information. We apply our proposed workflow to a case study in the Weiyuan area of the Sichuan Basin, China, a region targeted for shale gas production. By integrating diverse datasets, including 3D seismic, earthquakes, and well logs, we develop a comprehensive 3D model of in-situ stress(orientations and magnitudes). Our results demonstrate that the estimated anisotropy orientations from 3D seismic data are consistent with the direction of maximum horizontal principal stress(SHmax) obtained from FMIs. We analyzed 12earthquakes(magnitude > 3) recorded between 2016 and 2020 for their FMSs and compressional axis(Paxis) orientations. The derived SHmax direction from our 3D stress model is 110°ES(East-South), which shows excellent agreement with the FMSs(within 3.96°). This close alignment validates the reliability and precision of our integrated method for predicting 3D SHmax orientations.

关键词： In-situ stress orientation SHmax Azimuthal velocity anisotropy Focal source mechanism Formation micro-imager

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

A Trick to Control the Bleeding in Cardiovascular Surgery

引用

Chinese Medical Journal 2015年第7期128卷 988-988页

作者： Yi-Ming Ni Bold Altangerel Hong-Fei Xu hai-ge zhao Department of Thoracic and Cardiovascular Surgery First Affiliated Hospital of the Zhejiang University Hangzhou Zhejiang 310000 China Department of Thoracic Surgery National Cancer Center Bayanzurkh District Ulaanbaatar Mongolia

When accidental bleeding happens on the posterior wall of vena cava during the procedure of vena cava cannulation [Figure l a], two pieces of thymus gland tissue around 2 cm × 1 cm were taken as the mattress tips, and these two pieces of tissue were put aside the bottom of vena cava, then use Prolene （Ethicon, Somerville, N J, USA） to pass through the interspace under the posterior wall to make a mattress suture [Figure 1 b and c]. Knot is tied with adequate tension to eliminate any obvious bleeding and to achieve complete hemostasis [Figure l d]. In some cases, additional mattress sutures are needed to stop bleeding.

关键词： Bleeding Thynlus Gland Vena Cava Cannulation

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

Oxygen vacancies enriched Ir/WOx catalysts for the directly chem-catalytic conversion of cellulose to ethanol

引用

Tungsten 2025年第1期7卷 88-99页

作者： Yu-Jing Weng zhao-Ying Ding Ying-Chao Li Yuan-Feng Wu Yuan-Yang Xu Rui Chen Xiao-Lei zhao hai-Yong Wang Da-Lei Zhang Yu-Long Zhang Henan Key Laboratory of Coal Green Conversion and International Joint Laboratory of Coal Clean Utilization College of Chemistry and Chemical Engineering Henan Polytechnic University Key Laboratory of Renewable Energy Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Liaoning Institute of Energy Technology

Tungsten and its oxides are highly versatile catalysts with unique properties that hold great promise for a wide array of applications,including biological pathways and chemical *** chemo-catalysis of cellulose to ethanol presents a promising avenue for ethanol synthesis with the potential for enhanced efficiency compared to conventional methods,offering a sustainable and carbon-neutral alternative to existing petrochemical and biological ***,Ir/WOxcatalysts enriched with oxygen vacancies were meticulously prepared and demonstrated remarkable catalytic performance in converting cellulose to ethanol directly in the presence of tungstic *** catalyst achieved a high ethanol yield of 66.5%under optimal reaction conditions,approaching the theoretical yield limit of traditional ethanol *** results revealed the presence of oxygen defects,Bronsted/Lewis acidity,and Ir nanoclusters on the catalyst surface,working synergistically to facilitate the cascade catalysis of cellulose hydrolysis,sugar retro-aldol condensation reaction,and C2 intermediate hydrodeoxygenation to *** situ Fourier transform infrared spectrometer analysis confirmed the catalyst's ability to enhance the adsorption and activation of ethylene glycol for ethanol *** manipulating subtle structural features,this study offers a fresh perspective on tungsten group catalyst design and underscores the importance of synergistic effects among catalytic sites for the efficient production of ethanol from cellulose.

关键词： Cellulosic ethanol Chem-catalysis Hydrogenolysis Retro-aldol condensation Tungsten

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

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：