检索结果-南通市图书馆

Coupling effect of cement-stabilization and biopolymer-modification on the mechanical behavior of dredged sediment

Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3284-3298页

作者： Lei Lang Jiangshan Li Xiao Huang ping Wang wei Zhang State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China Hubei Provincial Key Laboratory of Contaminated Sludge and Soil Science and Engineering Wuhan430071China University of Chinese Academy of Sciences Beijing100049China

Nowadays,biopolymer stabilization as a promising eco-friendly approach in soft ground improvement has attracted wide ***,the feasibility of using biopolymer as a green additive of cementstabilized dredged sediment(CDS)with high water content is still *** this study,guar gum(GG)and xanthan gum(XG)were adopted as typical biopolymers,and a series of unconfined compressive strength(UCS),splitting tensile strength(STS)and scanning electron microscopy(SEM)tests were performed to evaluate the mechanical and microstructural properties of XG-and GG-modified CDSs considering several factors including biopolymer modification,binderesoil ratio and wateresolid ***,the micro-mechanisms revealing the evolutions of mechanical properties of biopolymermodified CDS were *** results indicate that the addition of XG can effectively improve the strength of CDS,while the GG has a side *** XG content of 9%was recommended,which can improve the 7 d-and 28 d-UCSs by 196%and 51.8%,together with the 7 d-and 28 d-STSs by 118.3%and 42.2%,*** the binderesoil ratio or decreasing the wateresolid ratio significantly improved the strength gaining but aggravated the brittleness characteristics of *** XG to CDS contributed to the formation of microstructure with more compactness and higher cementation degrees of ordinary Portland cement(OPC)-XG-stabilized DS(CXDS).The micro-mechanism models revealing the interactions of multiple media including OPC cementation,biopolymer film bonding and bridging effects inside CXDS were *** key findings confirm the feasibility of XG modification as a green and high-efficiency mean for improving the mechanical properties of CDS.

关键词： Dredged sediment(DS) Stabilization Biopolymer modification Mechanical properties Micro-mechanism

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

Equilibrium Reinsurance Strategy and Mean Residual Life Function

引用

Acta Mathematicae Applicatae Sinica 2024年第3期40卷 758-777页

作者： Dan-ping LI Lv CHEN Lin-yi QIAN wei WANG School of Statistics Key Laboratory of Advanced Theory and Application in Statistics and Data Science-MOEEast China Normal UniversityShanghai 200062China Academy of Statistics and Interdisciplinary Sciences Key Laboratory of Advanced Theory and Application in Statistics and Data Science-MOEEast China Normal UniversityShanghai 200062China School of Mathematics and Statistics Ningbo UniversityNingbo 315211China

In this paper,we analyze the relationship between the equilibrium reinsurance strategy and the tail of the distribution of the *** Mean Residual Life(MRL)has a close relationship with the tail of the distribution,we consider two classes of risk distributions,Decreasing Mean Residual Life(DMRL)and Increasing Mean Residual Life(IMRL)distributions,which can be used to classify light-tailed and heavy-tailed distributions,*** assume that the underlying risk process is modelled by the classical CramérLundberg model *** the mean-variance criterion,by solving the extended Hamilton-Jacobi-Bellman equation,we derive the equilibrium reinsurance strategy for the insurer and the reinsurer under DMRL and IMRL,***,we analyze how to choose the reinsurance premium to make the insurer and the reinsurer agree with the same reinsurance *** find that under the case of DMRL,if the distribution and the risk aversions satisfy certain conditions,the insurer and the reinsurer can adopt a reinsurance premium to agree on a reinsurance strategy,and under the case of IMRL,the insurer and the reinsurer can only agree with each other that the insurer do not purchase the reinsurance.

关键词： mean residual life excess-of-loss reinsurance insurer reinsurer stochastic control

来源：

维普期刊数据库

同方期刊数据库

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

Predictive utility of the Rockall scoring system in patients suffering from acute nonvariceal upper gastrointestinal hemorrhage

引用

World Journal of Gastrointestinal Surgery 2024年第8期16卷 2620-2629页

作者： De-ping Han cai-Qian Gou Xin-Mian Ren Department of Emergency Chengyang District People’s HospitalQingdao 266109Shandong ProvinceChina

BACKGROUND Acute non-variceal upper gastrointestinal bleeding(ANVUGIB)represents a sig-nificant clinical challenge due to its unpredictability and potentially severe *** Rockall risk score has emerged as a critical tool for prognostic asse-ssment in patients with ANVUGIB,aiding in the prediction of rebleeding and ***,its applicability and accuracy in the Chinese population remain *** To assess the prognostic value of the Rockall risk score in a Chinese cohort of patients with *** A retrospective analysis of 168 ANVUGIB patients’medical records was *** study employed statistical tests,including the t-test,χ^(2) test,spearman correlation,and receiver operating characteristic(ROC)analysis,to assess the re-lationship between the Rockall score and clinical outcomes,specifically focusing on rebleeding events within 3 months *** Significant associations were found between the Rockall score and various clinical *** Rockall scores were significantly associated with rebleeding events(r=0.735,R2=0.541,P<0.001)and strongly positively correlated with adverse *** hemoglobin levels(t=2.843,P=0.005),high international normalized ratio(t=3.710,P<0.001),active bleeding during endoscopy(χ^(2)=7.950,P=0.005),large ulcer size(t=6.348,P<0.001),and requiring blood transfusion(χ^(2)=6.381,P=0.012)were all significantly associated with rebleeding ***,differences in treatment and management strategies were identified between patients with and without rebleeding *** analysis indicated the excellent discriminative power(sensitivity:0.914;specificity:0.816;area under the curve:0.933;Youden index:0.730)of the Rockall score in predicting rebleeding events within 3 *** This study provides valuable insights into the prognostic value of the Rockall risk score for ANVUGIB in the Chinese *** results underscore the potential of the Rockall score as an effect

关键词： Acute non-variceal upper gastrointestinal bleeding Rockall risk score Clinical outcomes Risk stratification Prognosis

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

Single-Ni-atoms on nitrogenated humic acid based porous carbon for CO_(2) electroreduction

引用

Frontiers of Chemical Science and Engineering 2024年第5期18卷 37-47页

作者： Delei Yu Ying Chen Yao Chen Xiangchun Liu Xianwen wei ping Cui Anhui Key Laboratory of Coal Clean Conversion&Utilization School of Chemistry and Chemical EngineeringAnhui University of TechnologyMa’anshan 243002Chin

tWe proposed a facile synthesis of single-Ni-atom catalysts on low-cost porous carbon using a calcina-tion method at the temperatures of 850-1000°C,which were used for CO_(2) electrochemical reduction to *** porous carbon was prepared by carbonizing cheap and abundant humic *** structural characterizations of the as-synthesized catalysts and their electrocatalytic performances were *** results showed that the single-Ni-atom catalyst activated at 950°C showed an optimum catalytic performance,and it reached a CO Faradaic efficiency of 91.9% with a CO partial current density of 6.9 mAcm^(-2)at-0.9 V *** hydrogen electrode(RHE).Additionally,the CO Faradaic efficiency and current density of the optimum catalyst changed slightly after 8 h of continuous operation,suggesting that it possessed an excellent *** structure-activity relations indicate that the variation in the CO_(2) electroche-mical reduction performance for the as-synthesized catalysts is ascribed to the combined effects of the increase in the content of pyrrolic N,the evaporation of Ni and N,the decrease in pore volume,and the change in graphitization degree.

关键词： CO_(2) electroreduction single-Ni-atom cataly-sts humic acid based porous carbon

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

Correlative Mn-Co catalyst excels Pt in oxygen reduction reaction of quasi-solid-state zinc-air batteries

引用

Nano Research 2024年第5期17卷 4118-4124页

作者： Tingting Wang Jincheng Huang wei Sang cai Zhou Bohan Zhang wei Zhu Kang Du Zongkui Kou Shengxiang Wang School of Mathematical and Physical Sciences Wuhan Textile UniversityWuhan 430200China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Zn-air batteries(ZABs)as a class of promising energy storage setups are generally powered by efficient and robust catalysts at the oxygen-involving *** the existing non-noble catalysts have outperformed noble Pt benchmark in the alkaline liquid-state ZABs,to the best of our knowledge few have excelled Pt in quasi-solid-state(QSS)***,we found that an integrated Mn-Co cathode derived from the bimetallic Mn/Co metal organic frameworks generates a 1.4-fold greater power density in the QSS ZABs than a Pt cathode while its power density in liquid-state ZABs is only 0.8-fold of the ***,such Mn-Co catalyst delivers high-rate oxygen reduction reaction(ORR)capability with half-wave potential of 0.84 *** in-depth characterizations and analyses have demonstrated that the Co and Mn species show the specific affinity towards H_(2)O and O_(2),respectively,synergizing the ORR process in the water-deficient environment of QSS *** work has enlightened the rational design of non-noble metal catalysts to improve the power density of QSS ZABs.

关键词： non-noble metal catalysts zinc-air battery quasi-solid-state synergistic effect

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

Theoretical understanding of correlation between magnetic phase transition and the superconducting dome in high-Tc cuprates

引用

Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 167-173页

作者： Chen Zhang cai-Xin Zhang Su-Huai wei Haiqing Lin Hui-Xiong Deng State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Beijing Computational Science Research Center Beijing 100193China

Many issues concerning the origin of high-temperature superconductivity(HTS)are still under *** example,how the magnetic order varies with doping and its relationship with the superconducting temperature(Tc);and why Tcalways peaks near the quantum critical *** this paper,taking hole-doped La_(2)CuO_(4)as a classical example,we employ the first-principles band structure and total energy calculations with Monte Carlo simulations to explore how the symmetry-breaking magnetic ground state evolves with hole doping and the origin of a dome-shaped superconductivity region in the phase *** demonstrate that the local antiferromagnetic order and doping play key roles in determining the electron-phonon coupling,thus ***,the La_(2)CuO_(4)possesses a checkerboard local antiferromagnetic ground *** the hole doping increases,Tcincreases with the enhanced electron-phonon coupling *** as the doping increases further,the strength of the antiferromagnetic interaction weakens and spin fluctuation *** the critical doping level,a magnetic phase transition occurs that reduces the local antiferromagnetism-assisted electron-phonon coupling,thus diminishing the *** superconductivity disappears in the heavily overdoped region when the ferromagnetic order *** observations could account for why cuprates have a dome-shaped superconductivity region in the phase *** study,thus,contributes to a fundamental understanding of the correlation between doping,local magnetic order,and superconductivity of HTS.

关键词： high-temperature superconductivity antiferromagnetic order electron-phonon coupling doping effect cuprates

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

Combinatorial reasoning-based abnormal sensor recognition method for subsea production control system

引用

Petroleum Science 2024年第4期21卷 2758-2768页

作者： Rui Zhang Bao-ping cai Chao Yang Yu-Ming Zhou Yong-Hong Liu Xin-Yang Qi College of Mechanical and Electronic Engineering China University of Petroleum BGP Inc. China National Petroleum Corporation

The subsea production system is a vital equipment for offshore oil and gas production. The control system is one of the most important parts of it. Collecting and processing the signals of subsea sensors is the only way to judge whether the subsea production control system is normal. However, subsea sensors degrade rapidly due to harsh working environments and long service time. This leads to frequent false alarm incidents. A combinatorial reasoning-based abnormal sensor recognition method for subsea production control system is proposed. A combinatorial algorithm is proposed to group sensors. The long short-term memory network(LSTM) is used to establish a single inference model. A counting-based judging method is proposed to identify abnormal sensors. Field data from an offshore platform in the South China Sea is used to demonstrate the effect of the proposed method. The results show that the proposed method can identify the abnormal sensors effectively.

关键词： Abnormal sensor Combinatorial algorithm Fault identification Subsea production control system

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

Overview of computation strategies on the dispersion analysis for explicit finite difference solution of acoustic wave equation

引用

Petroleum Science 2024年第4期21卷 2311-2328页

作者： Jian-ping Huang wei-Ting Peng Ji-Dong Yang Lu-Feng Lou School of Geosciences China University of Petroleum (East China) Pilot National Laboratory for Marine Science and Technology (Qingdao)

Finite-difference(FD) method is the most extensively employed numerical modeling technique. Nevertheless, when using the FD method to simulate the seismic wave propagation, the large spatial or temporal sampling interval can lead to dispersion errors and numerical instability. In the FD scheme, the key factor in determining both dispersion errors and stability is the selection of the FD weights. Thus,How to obtain appropriate FD weights to guarantee a stable numerical modeling process with minimum dispersion error is critical. The FD weights computation strategies can be classified into three types based on different computational ideologies, window function strategy, optimization strategy, and Taylor expansion strategy. In this paper, we provide a comprehensive overview of these three strategies by presenting their fundamental theories. We conduct a set of comparative analyses of their strengths and weaknesses through various analysis tests and numerical modelings. According to these comparisons, we provide two potential research directions of this field: Firstly, the development of a computational strategy for FD weights that enhances stability; Secondly, obtaining FD weights that exhibit a wide bandwidth while minimizing dispersion errors.

关键词： Finite-difference scheme FD coefficients Dispersion error Forward modeling Numerical simulation

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

Interplay between the atomic structures and superconductivity of two-monolayer Pb films

引用

Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 90-98页

作者： Kun Xie Ze Huang Pengju Li Yumin Xia Desheng cai Yitong Gu Yuzhou Liu Fangliang cai Runxiao Zhang Haohao Shi ping Cui Shengyong Qin International Center for Quantum Design of Functional Materials(ICQD) University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Strongly Coupled Quantum Matter Physics Department of PhysicsUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China

Superconductors with reduced dimensionality have been widely explored for their exotic superconducting ***,at the two-dimensional limit,two-monolayer Pb films with two types of structures provide an ideal platform to unveil the underlying superconducting mechanism[Science 324,1314(2009)].Here,by combining scanning tunneling microscopy(STM)with the first-principle calculations,we successfully identify that these two types have different atomic lattice structures with varying stacking phases,which further enables us to calculate the phonon spectrum and electron phonon coupling strength of each *** theoretical calculations are in good agreement with tunneling spectroscopy measurements of the superconducting transition temperatures(T_(c)),which established a correlation between atomic structures and ***,it was observed that the higher T_(c)of these two types also possess higher out-of-plane upper critical magnetic fields(Hc2).These findings will provide important new insights into two-dimensional superconductivity at the atomic level.

关键词： 2 ML Pb films superconductivity atomic structure scanning tunneling microscopy first-principle calculations

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

MicroRNA let-7 targets BmCDK1 to regulate cell proliferation and endomitosis of silk gland in the silkworm,Bombyx mori

引用

Insect Science 2024年第4期31卷 1026-1040页

作者： wei Wang Linshengzhe Ji Xinyuan Jing ping Zhao Qingyou Xia Integrative Science Center of Germplasm Creation in Western China(Chongqing)Science City Biological Science Research CenterSouthwest UniversityChina Key Laboratory for Germplasm Creation in Upper Reaches of the Yangtze River Ministry of Agriculture and Rural AffairsChongqingChina Engineering Laboratory of Sericultural and Functional Genome and Biotechnology Development and Reform CommissionChongqingChina

MicroRNAs play critical roles in multiple developmental processes in *** previous study showed that CRISPR/Cas9-mediated knock down of the microRNA let-7 in silkworms increased the size of larvae and silk glands,thereby improving the silk production *** this study,we elucidate the molecular mechanism underlying of let-7 regulates *** of differentially expressed genes in response to let-7 knock down revealed enrichment of pathways associated with cell proliferation and DNA ***-7 dysregulation affected the cell cycle and proliferation of the Bombyx mori cell line ***-luciferase and target site mutation assays showed that BmCDK1 is a direct target gene of let-7,with only 1 binding site on its 3′-untranslated *** interference of BmCDK1 inhibited cell proliferation,but this effect was counteracted by co-transfection with let-7 ***,let-7 knock down induced BmCDK1 expression and promoted cell proliferation in multiple tissues,and further induced endomitosis in the silk gland in *** down of BmCDK1 resulted in abnormal formation of a new epidermis,and larval development was arrested at the 2nd or 3rd molt *** together,our results demonstrated that BmCDK1 is a novel target of let-7 in cell fate determination,possessing potential for improving silk yield in silkworm.

关键词： BmCDKI CRISPR/Cas9 cell proliferation let-7 silkworm

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

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：