检索结果-南通市图书馆

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第3期25卷 268-274页

作者： Jjijie YE xuan xu Chuande WU Department of Chemistry Zhejiang UniversityHangzhou 310058China

Three polyoxometalate-based hybrid coordination materials,[Co_(8)(H_(2)O)_(34)(pz)_(2){Co_(4)(H_(2)O)_(2)P_(4)W_(30)O_(112)}]·16H_(2)O(compound 1),[H_(3)O]_(4)[Co_(6)(H_(2)O)_(22)(pz)_(2){Co_(4)(H_(2)O)_(2)P_(4)W_(30)O_(112)}]·21H_(2)(compound 2),and[H_(3)O]_(4)[Co_(6)(H_(2)O)_(22){Co_(4)(H_(2)O)_(2)P_(4)W_(30)O_(112)}]·29H_(2)O(compound 3)(pz-pyrazine),were built from the linkage of[Co_(4)(H_(2)O)_(2)(P_(2)W_(15)O_(56)_(2)]^(16-)-(abbreviated as{Co_(4)P_(4)W_(30})polyanions and pz and/or cobalt(II)cations.Although compounds 1 and 2 consisted of the same components,their lamellar networks were quite different.The inorganic lamellar network in compound 3 was constructed by connecting{Co_(4)P_(4)W_(30)}units with cobalt(I)cations.This work demonstrates that the coordination modes of{Co_(4)P_(4)W_(30)}are very sensitive to synthesis conditions,while the ring-belt tetrametals are easily substituted by different transition metal cations under mild reaction conditions.

关键词： Cobalt Crystal structure Cyclic voltammetry Hybrid Polyoxometalate

Brain Pathology in COVID-19:Clinical Manifestations and Potential Mechanisms

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neuroscience Bulletin 2024年第3期40卷 383-400页

作者： Zhixing xu Hui Wang Siya Jiang Jiao Teng Dongxu Zhou Zhong Chen Chengping Wen Zhenghao xu First School of Clinical Medicine Zhejiang Chinese Medical UniversityHangzhou 310053China School of Pharmaceutical Sciences Zhejiang Chinese Medical UniversityHangzhou 310053China Second School of Clinical Medicine Zhejiang Chinese Medical UniversityHangzhou 310053China Afliated Lin’an People’s Hospital of Hangzhou Medical College First People’s Hospital of Hangzhou Lin’an DistrictLin’anHangzhou 311300China School of Life Sciences Zhejiang Chinese Medical UniversityHangzhou 310053China Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province College of Pharmaceutical ScienceZhejiang Chinese Medical UniversityHangzhou 310053China Laboratory of Rheumatology and Institute of TCM Clinical Basic Medicine College of Basic Medical ScienceZhejiang Chinese Medical UniversityHangzhou 310053China

Neurological manifestations of coronavirus disease 2019(COVID-19)are less noticeable than the respiratory symptoms,but they may be associated with disability and mortality in COVID-19.Even though Omicron caused less severe disease than Delta,the incidence of neurological manifestations is similar.More than 30%of patients experienced“brain fog”,delirium,stroke,and cognitive impairment,and over half of these patients presented abnormal neuroimaging outcomes.In this review,we summarize current advances in the clinical findings of neurological manifestations in COVID-19 patients and compare them with those in patients with influenza infection.We also illustrate the structure and cellular invasion mechanisms of SARS-CoV-2 and describe the pathway for central SARS-CoV-2 invasion.In addition,we discuss direct damage and other pathological conditions caused by SARS-CoV-2,such as an aberrant interferon response,cytokine storm,lymphopenia,and hypercoagulation,to provide treatment ideas.This review may offer new insights into preventing or treating brain damage in COVID-19.

关键词： COVID-19 SARS-CoV-2 Brain Neurological pathology

A novel rapid cooling assembly design in a high-pressure cubic press apparatus

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Matter and Radiation at Extremes 2024年第2期9卷 98-104页

作者： Peiyan Wu Yongjiang xu Yanhao Lin Center for High Pressure Science and Technology Advanced Research Beijing 100193People’s Republic of China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083People’s Republic of China

In traditional high-pressure–temperature assembly design, priority has been given to temperature insulation and retention at high pressures.This limits the efficiency of cooling of samples at the end of experiments, with a negative impact on many studies in high-pressure Earth andplanetary science. Inefficient cooling of experiments containing molten phases at high temperature leads to the formation of quench textures,which makes it impossible to quantify key compositional parameters of the original molten phase, such as their volatile contents. Here,we present a new low-cost experimental assembly for rapid cooling in a six-anvil cubic press. This assembly not only retains high heatingefficiency and thermal insulation, but also enables a very high cooling rate (∼600 ℃/s from 1900 ℃ to the glass transition temperature).Without using expensive materials or external modification of the press, the cooling rate in an assembly (∼600 ℃/s) with cube lengths of38.5 mm is about ten times faster than that in the traditional assembly (∼60 ℃/s). Experiments yielding inhomogeneous quenched melttextures when the traditional assembly is used are shown to yield homogeneous silicate glass without quench textures when the rapid coolingassembly is used.

关键词： cubic insulation apparatus

Unconditionally stable Crank-Nicolson algorithm with enhanced absorption for rotationally symmetric multi-scale problems in anisotropic magnetized plasma

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2024年第1期35卷 65-73页

作者： WEN Yi WANG Junxiang xu Hongbing School of Automatic Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Beijing Institute of Aerospace Systems Engineering Beijing 100076China

Large calculation error can be formed by directly employing the conventional Yee’s grid to curve surfaces.In order to alleviate such condition,unconditionally stable CrankNicolson Douglas-Gunn(CNDG)algorithm with is proposed for rotationally symmetric multi-scale problems in anisotropic magnetized plasma.Within the CNDG algorithm,an alternative scheme for the simulation of anisotropic plasma is proposed in body-of-revolution domains.Convolutional perfectly matched layer(CPML)formulation is proposed to efficiently solve the open region problems.Numerical example is carried out for the illustration of effectiveness including the efficiency,resources,and absorption.Through the results,it can be concluded that the proposed scheme shows considerable performance during the simulation.

关键词： anisotropic magnetized plasma body-of-revolution(BOR) Crank-Nicolson Douglas-Gunn(CNDG) finite-difference time-domain(FDTD) perfectly matched layer(PML) rotationally symmetric multi-scale problems

Structure and mechanical properties of windmill palm fiber with different delignification treatments

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

Journal of Bioresources and Bioproducts 2024年第1期9卷 102-112页

作者： Changjie Chen Pengfei xu Xinhou Wang Key Laboratory of Textile Science&Technology(Donghua University) Ministry of EducationCollege of Textiles2999 Renmin North RoadShanghai 201620China Basalt Fiber and Composite Key Laboratory of Sichuan Province Sichuan 635000China College of Mechanical Engineering Donghua UniversityShanghai 201620China National Engineering Laboratory for Modern Silk Soochow UniversitySuzhou 215123China Shanghai Composite Technology Co.Ltd. Shanghai 201112China

The removal of lignin from natural cellulose fibers is a crucial step in preparing high-performance materials,such as compressed high-toughness composites.This process can eliminate non-cellulosic impurities,create abundant compressible pores,and expose a greater number of active functional groups.In this study,biomass waste windmill palm fiber was used as the raw mate-rial to prepare holocellulose fibers through various chemical treatments.The structure,chemical composition,Fourier transform infrared spectroscopy analysis,X-ray diffraction analysis,ther-mal properties,and mechanical properties,particularly fatigue performance,were studied.The sodium chlorite treated fiber had the highest crystallinity index(61.3%)and the most complete appearance structure.The sodium sulfite treated fiber had the highest tensile strength(227.34±52.27)MPa.Hydroxide peroxide treatment removed most of the lignin and hemicellulose,increas-ing the cellulose content to 68.83%±0.65%.However,all the chemical treatments decreased the thermal property of the fibers.

关键词： Windmill palm fiber Delignification treatment Morphonology Mechanical property Fatigue property

A risk assessment method considering risk attributes and work safety informational needs and its application

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2024年第4期68卷 253-262页

作者： Cong Luo Yunsheng Zhao Ke xu School of Political Science and Public Administration Shandong UniversityQingdao 266200China Faculty of Engineering China University of GeosciencesWuhan 430074China Department of Emergency Management of Hubei Province Wuhan 430064China

The technological revolution has spawned a new generation of industrial systems,but it has also put forward higher requirements for safety management accuracy,timeliness,and systematicness.Risk assessment needs to evolve to address the existing and future challenges by considering the new demands and advancements in safety management.The study aims to propose a systematic and comprehensive risk assessment method to meet the needs of process system safety management.The methodology first incorporates possibility,severity,and dynamicity(PSD)to structure the“51X”evaluation indicator system,including the inherent,management,and disturbance risk factors.Subsequently,the four-tier(risk point-unit-enterprise-region)risk assessment(RA)mathematical model has been established to consider supervision needs.And in conclusion,the application of the PSD-RA method in ammonia refrigeration workshop cases and safety risk monitoring systems is presented to illustrate the feasibility and effectiveness of the proposed PSD-RA method in safety management.The findings show that the PSD-RA method can be well integrated with the needs of safety work informatization,which is also helpful for implementing the enterprise's safety work responsibility and the government's safety supervision responsibility.

关键词： Risk assessment Safey “51X”evaluation indicator system Four-tier risk assessment model Risk attributes Process system

Toward tunable shape memory effect of NiTi alloy by grain size engineering:A phase field study

维普期刊数据库

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第1期168卷 276-289页

作者： Bo xu Chong Wang Qingyuan Wang Failure Mechanics and Engineering Disaster Prevention Key Laboratory of Sichuan ProvinceSichuan UniversityChengdu 610065China Department of Mechanical Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China Key Laboratory of Deep Underground Science and Engineering (Sichuan University)Ministry of EducationChengdu 610065China

The inelastic deformations of shape memory alloys(SMAs)always show poor controllability due to the avalanche-like martensite transformation,and the effective control for the deformation of precision de-vices has been not yet mature.In this work,the phase field method was used to investigate the shape memory effects(SMEs)of NiTi SMAs undergoing grain size(GS)engineering,to obtain tunable one-way and stress-assisted two-way SMEs(OWSME and SATWSME).The OWSME and SATWSME of the systems with various gradient-nanograin structures and bimodal grain structure,as well as that with geometric gradients were simulated.The simulated results indicate that due to the GS dependences of martensite transformation and reorientation,the occurrence and expansion of martensite reorientation,martensite transformation and its reverse can be efficaciously controlled via the GS engineering.When combining the GS engineering and geometric gradient design,since the effects of GS and stress gradient can be su-perimposed or competing,and the responses of martensite reorientation,martensite transformation and its reverse to this are different,the OWSME and SATWSME of the geometrically graded systems with various nanograin structures can exhibit different improvements in controllability.In short,the reorienta-tion hardening modulus during OWSME is increased and the transformation temperature window during SATWSME is widened by GS engineering,indicating the improved controllability of SMEs.The optimal GS engineering schemes revealed in this work provide the basic reference and guidance for designing tun-able SMEs and producing NiTi-based driving devices catering to desired functional performance in various engineering fields.

关键词： Phase field NiTi Shape memory effect Grain size engineering Geometric gradient

Risk factors,prognostic factors,and nomograms for distant metastasis in patients with diagnosed duodenal cancer:A population-based study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2024年第4期16卷 1384-1420页

作者： Jia-Rong Shang Chen-Yi xu Xiao-xue Zhai Zhe xu Jun Qian Department of Oncology Jiangsu Province Hospital of Chinese MedicineThe Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210000Jiangsu ProvinceChina Department of Proctology Nanjing Hospital of Chinese MedicineNanjing 210000Jiangsu ProvinceChina Department of Digestive Cancer Surgery Jiangsu Province Hospital of Chinese MedicineThe Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210000Jiangsu ProvinceChina

BACKGROUND Duodenal cancer is one of the most common subtypes of small intestinal cancer,and distant metastasis(DM)in this type of cancer still leads to poor prognosis.Although nomograms have recently been used in tumor areas,no studies have focused on the diagnostic and prognostic evaluation of DM in patients with primary duodenal cancer.AIM To develop and evaluate nomograms for predicting the risk of DM and person-alized prognosis in patients with duodenal cancer.METHODS Data on duodenal cancer patients diagnosed between 2010 and 2019 were extracted from the Surveillance,Epidemiology,and End Results database.Univariate and multivariate logistic regression analyses were used to identify independent risk factors for DM in patients with duodenal cancer,and univariate and multivariate Cox proportional hazards regression analyses were used to determine independent prognostic factors in duodenal cancer patients with DM.Two novel nomograms were established,and the results were evaluated by receiver operating characteristic(ROC)curves,calibration curves,and decision curve analysis(DCA).RESULTS A total of 2603 patients with duodenal cancer were included,of whom 457 cases(17.56%)had DM at the time of diagnosis.Logistic analysis revealed independent risk factors for DM in duodenal cancer patients,including gender,grade,tumor size,T stage,and N stage(P<0.05).Univariate and multivariate COX analyses further identified independent prognostic factors for duodenal cancer patients with DM,including age,histological type,T stage,tumor grade,tumor size,bone metastasis,chemotherapy,and surgery(P<0.05).The accuracy of the nomograms was validated in the training set,validation set,and expanded testing set using ROC curves,calibration curves,and DCA curves.The results of Kaplan-Meier survival curves(P<0.001)indicated that both nomograms accurately predicted the occurrence and prognosis of DM in patients with duodenal cancer.CONCLUSION The two nomograms are expected as effective tools for predicting DM risk in duodenal cancer patients

关键词： Duodenal cancer Distant metastasis Nomogram Risk factors Prognostic factors

Linear Quadratic Optimal Control for Systems Governed by First-Order Hyperbolic Partial Differential Equations

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2024年第1期37卷 230-252页

作者： xuE Xiaomin xu Juanjuan ZHANG Huanshui School of Control Science and Engineering Shandong UniversityJinan 250061China College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266000China

This paper focuses on linear-quadratic(LQ)optimal control for a class of systems governed by first-order hyperbolic partial differential equations(PDEs).Different from most of the previous works,an approach of discretization-then-continuousization is proposed in this paper to cope with the infinite-dimensional nature of PDE systems.The contributions of this paper consist of the following aspects:(1)The differential Riccati equations and the solvability condition of the LQ optimal control problems are obtained via the discretization-then-continuousization method.(2)A numerical calculation way of the differential Riccati equations and a practical design way of the optimal controller are proposed.Meanwhile,the relationship between the optimal costate and the optimal state is established by solving a set of forward and backward partial difference equations(FBPDEs).(3)The correctness of the method used in this paper is verified by a complementary continuous method and the comparative analysis with the existing operator results is presented.It is shown that the proposed results not only contain the classic results of the standard LQ control problem of systems governed by ordinary differential equations as a special case,but also support the existing operator results and give a more convenient form of computation.

关键词： Discretization-then-continuousization method first-order hyperbolic partial differential equations forward and backward partial difference equations linear quadratic optimal control.

Synthesis and characterization of iron clusters with an icosahedral [Fe@Fe12]16+ Core

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

National Science Review 2024年第4期11卷 123-129页

作者： Gan xu Yun-Shu Cui xue-Lian Jiang Cong-Qiao xu Jun Li xu-Dong Chen Jiangsu Collaborative Innovation Center of Biomedical Functional Materials and Jiangsu Key Laboratory of New Power Batteries School of Chemistry and Materials Science Nanjing Normal University Department of Chemistry and Guangdong Provincial Key Laboratory of Catalytic Chemistry Southern University of Science and Technology Department of Chemistry and Engineering Research Center of Advanced Rare-Earth Materials of Ministry of Education Tsinghua University State Key Laboratory of Coordination Chemistry Nanjing University

Iron-metal clusters are crucial in a variety of critical biological and material systems,including metalloenzymes,catalysts,and magnetic storage devices.However,a synthetic high-nuclear iron cluster has been absent due to the extreme difficulty in stabilizing species with direct iron-iron bonding.In this work,we have synthesized,crystallized,and characterized a（Tp*）4W4S12(Fe@Fe12) cluster(Tp*=tris（3,5-dimethyl-1-pyrazolyl）borate（1-）),which features a rare trideca-nuclear,icosahedral[Fe@Fe12] cluster core with direct multicenter iron-iron bonding between the interstitial iron（Fei） and peripheral irons（Fep）,as well as Fep…Fepferromagnetic coupling.Quantum chemistry studies reveal that the stability of the cluster arises from the 18-electron shell-closing of the [Fe@Fe12]16+core,assisted by its bonding interactions with the peripheral tridentate [（Tp*）WS3]4-ligands which possess both S→Fe donation and spin-polarized Fe-Wσ bonds.The ground-state electron spin is theoretically predicted to be S=32/2 for the cluster.The existence of low oxidation-state（OS～+1.23） iron in this compound may find interesting applications in magnetic storage,spintronics,redox chemistry,and cluster catalysis.

关键词： Fe13 cluster iron-sulfur cluster low-valence iron iron−iron bond high spin complex