检索结果-南通市图书馆

Influence of cerium and yttrium addition on strength and electrical conductivity of pure aluminum alloys

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第3期42卷 600-611,I0006页

作者： guojian lin Lu li Zhengwei guo Xianjun Jia Xiao Wang Zhentao Yuan guoxing Zhang yun Zhan Quan Shan Zulai li Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming650093China Research Center for Analysis and Measurement Kunming University of Science and TechnologyKunming650093China City College Kunming University of Science and TechnologyKunming650051China

To develop pure aluminum alloys with high conductivity and strength, Al-0.2Ce and Al-0.2Ce-0.1Y alloys were prepared by rolling and annealing processes in this study. The effects of trace rare earth elements on the strength and electrical conductivity of the pure aluminum alloys were investigated. It is revealed that the addition of Ce and Y to pure aluminum can effectively enhance the strength and electrical conductivity of the alloys. In Al-0.2Ce, the addition of Ce can effectively refine the grain size of a-Al, with an average grain size of 90.68 μm in the as-cast state. The grain size of the alloy is further reduced to 87.55 μm by the simultaneous addition of Y. The synergistic addition of Ce and Y changes the properties of the alloy. The addition of Ce and Y also produces the Al_(11)Ce_(3) and Al_(3)Y second phases, which have coherent relationship with a-Al. The two-dimensional mismatch degree was calculated to be only 4.43%and 0.85%, respectively, which can provide a certain amount of nucleation substrate for a-Al in the incubation stage. The interfacial match between the L1_(2)structure of Al_(3)Y and a-Al was calculated using first-principles simulations. The results indicate that Al_(3)Y has a strong bonding effect with a-Al. Nanoscale second phases at grain boundaries can be effective in reducing resistivity due to dislocation *** second phases with better matching interfaces to the substrate have no positive effect on the scattering motion of electrons.

关键词： Pure aluminum Rare earths Impurity purification First-principles calculations Strength-conductivity contradiction

Pd@Ir-LOD multienzyme utilizing endogenous lactate consumption cooperates with photothermal for tumor therapy

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第1期17卷 270-281页

作者： Zichen Ye yun li Jingchao li Xinyan Hu Jinyang Zheng Gongxin Zhang Sijin Xiang Tianbao Zhu Zhide guo Xiaolan Chen State Key Laboratory for Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materials and Engineering Research Center for Nano-Preparation Technology of Fujian ProvinceCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics&Center for Molecular Imaging and Translational Medicine School of Public Health Xiamen UniversityXiamen 361102China The High Educational Key Laboratory for Biomedical Engineering&Key Laboratory of Fire Retardant Materials of Fujian Province Department of BiomaterialsCollege of MaterialsXiamen UniversityXiamen 361102China

Lactic acid(LA)plays a major role in the occurrence,development,and spread of *** by its high accumulation in tumor site,a novel lactate oxidase(LOD)conjugated two-dimensional Pd@Ir nanoplatform(Pd@Ir-LOD,PIL)was fabricated to combine cascade reaction with photothermal for tumor *** detail,the overexpressed LA in tumor microenvironment(TME)was a key factor to activate the PIL-based cascade reaction:(1)Plenty of H_(2)O_(2)could be generated from LA by the catalysis of LOD with O_(2);(2)potent·OH was produced from H_(2)O_(2)due to the peroxidase(POD)-like activity of PIL;(3)meantime,PIL’s catalase(CAT)-like activity could decompose part H_(2)O_(2)into O_(2)to achieve the purpose of LA cyclic ***,the reduced glutathione(GSH)scavenging capability of PIL might protect the produced reactive oxygen species(ROS)from being cleared to further improve the cascade therapeutic *** importantly,PIL had excellent photothermal conversion efficiency(37.35%)and manifested a surprising temperature rising effect in *** together,the decreasing LA concentration,accumulation of high-toxic ROS,the depletion of GSH together with the higher intra-tumoral temperature potently enhanced in vivo antitumor ***,a promising therapeutic tactic based on PIL integrating endogenous LA consumption,chemodynamic therapy(CDT),and photothermal therapy(PTT)has been put forward.

关键词： lactate oxidase chemodynamic therapy photothermal therapy cascade reaction tumor microenvironment

Application of a concrete thermal pile in cooling the warming permafrost under climate change

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Climate Change Research 2024年第1期15卷 170-183页

作者： yun-Hu SHANG Fu-Jun NIU guo-Yu li Jian-Hong FANG Ze-Yong GAO State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Da Xing'anling Observation and Research Station of Frozen-Ground Engineering and Environment Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesJagdaqi 165000China Qinghai Research Institute of Transportation Xining 810008China

Permafrost degradation caused by climate warming is posing a serious threat to the stability of cast-in-place pile foundations in warm permafrost *** cold energy can be effectively utilized by two-phase closed thermosyphons(TPCTs)to cool the ***,we installed TPCTs in a cast-in-place pile foundation to create a unique structure called a thermal pile,which effectively utilizes the TPCTs to regulate ground *** we conducted a case study and numerical simulation to exhibit the cooling performance,and optimize the structure of the thermal *** purpose of this study is to promote the application of thermal piles in unstable permafrost *** on the findings,the thermal pile operated for approximately 53%of the entire year and effectively reduced the deep ground temperature at a rate of at least-0.1℃per ***,it successfully raised the permafrost table that is 0.35 m shallower than the natural ground *** characteristics prove highly beneficial in mitigating the adverse effects of permafrost degradation and enhancing infrastructure *** the length of the condenser section and the diameter of the TPCT in a suitable manner can effectively enhance the cooling capability of the thermal pile and ensure the long-term mechanical stability of the pile foundation even under climate warming.

关键词： Heat transfer Cold energy Warm permafrost Two-phase closed thermosyphons Cast-in-place pile foundation

Long Non-coding RNA PCED1B Antisense RNA 1 Promotes Cell Proliferation and Invasion in Hepatocellular Carcinoma by Regulating the MicroRNA-34a/CD44 Axis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Current Medical Science 2024年第3期44卷 503-511页

作者： Jian-gang BI Qi li Yu-sheng guo li-ping liU Shi-yun BAO Ping XU Department of Hepatobiliary and Pancreatic Surgery Shenzhen People's HospitalThe Second Clinical Medical CollegeJinan UniversityThe First Affiliated HospitalSouthern University of Science and TechnologyShenzhen 518020China Department of Endocrinology Shenzhen People's HospitalThe Second Clinical Medical CollegeJinan UniversityThe First Affiliated HospitalSouthern University of Science and TechnologyShenzhen 518020China

Objective This study aimed to examine the role of long non-coding RNA PCED1B antisense RNA 1(PCED1B-AS1)in the development of hepatocellular carcinoma(HCC).Methods A total of 62 pairs of HCC tissues and adjacent non-tumor tissues were obtained from 62 HCC *** interactions of PCED1B-AS1 and microRNA-34a(miR-34a)were detected by dual luciferase activity assay and RNA pull-down *** RNA expression levels of PCED1B-AS1,miR-34a and CD44 were detected by RT-qPCR,and the protein expression level of CD44 was determined by Western *** cell proliferation was detected by cell proliferation assay,and the cell invasion and migration by transwell invasion *** HCC tumor growth after PCED1B-AS1 was downregulated was determined by in vivo animal *** PCED1B-AS1 was highly expressed in HCC tissues,which was associated with poor survival of HCC ***,PCED1B-AS1 interacted with miR-34a in HCC cells,but they did not regulate the expression of each ***,PCED1B-AS1 increased the expression level of CD44,which was targeted by *** cell proliferation and invasion assay revealed that miR-34a inhibited the proliferation and invasion of HCC in vitro,while CD44 exhibited the opposite ***,PCED1B-AS1 suppressed the role of ***,the knockdown of PCED1B-AS1 repressed the HCC tumor growth in nude mice in *** PCED1B-AS1 may play an oncogenic role by regulating the miR-34a/CD44 axis in HCC.

关键词： long non-coding RNA PCED1B antisense RNA 1(PCED1B-AS1) hepatocellular carcinoma microRNA-34a(miR-34a) CD44 proliferation invasion

A whole process damage constitutive model for layered sandstone under uniaxial compression based on Logistic function

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 Central South University 2024年第7期31卷 2411-2430页

作者： liU Dong-qiao guo yun-peng liNG Kai li Jie-yu State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology-BeijingBeijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology-BeijingBeijing 100083China

Bedding structural planes significantly influence the mechanical properties and stability of engineering rock *** study conducts uniaxial compression tests on layered sandstone with various bedding angles(0°,15°,30°,45°,60°,75°and 90°)to explore the impact of bedding angle on the deformational mechanical response,failure mode,and damage evolution processes of *** develops a damage model based on the Logistic equation derived from the modulus’s degradation considering the combined effect of the sandstone bedding dip angle and *** model is employed to study the damage accumulation state and its evolution within the layered rock *** research also introduces a piecewise constitutive model that considers the initial compaction characteristics to simulate the whole deformation process of layered sandstone under uniaxial *** results revealed that as the bedding angle increases from 0°to 90°,the uniaxial compressive strength and elastic modulus of layered sandstone significantly decrease,slightly increase,and then decline *** corresponding failure modes transition from splitting tensile failure to slipping shear failure and back to splitting tensile *** indicated by the modulus’s degradation,the damage characteristics can be categorized into four stages:initial no damage,damage initiation,damage acceleration,and damage deceleration *** theoretical damage model based on the Logistic equation effectively simulates and predicts the entire damage evolution ***,the theoretical constitutive model curves closely align with the actual stress−strain curves of layered sandstone under uniaxial *** introduced constitutive model is concise,with fewer parameters,a straightforward parameter determination process,and a clear physical *** study offers valuable insights into the theory of layered rock mechanics and holds implications for ensuring the safety of rock engineering.

关键词： layered sandstone uniaxial compression damage evolution Logistic function constitutive model

light People:*** Mazur speaks about ultrafast optics and education

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

light(Science & Applications) 2024年第3期13卷 402-406页

作者： Chenzi guo Yang li Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchunChina State Key Laboratory of Precision Measurement Technology and Instrument Department of Precision InstrumentTsinghua UniversityBeijingChina

*** Mazur is a great influencer over and beyond the optics *** a physicist,he is a pioneer of ultrafast optics and was one of the inventors of colliding-pulse mode-locked *** an educator,he not only gave talks to thousands,but also revolutionized teaching with his globally renowned methodology“Peer Instruction”.As a leader and entrepreneur,he co-founded several companies and was President of Optica(formerly the Optical Society)and currently is the Chair of the Optica ***,light:Science&Applications talked with *** Mazur about his opinions on research,education and *** full interview video can be found in the Supplementary File.

关键词： optics education companies

A unified stochastic damage model for concrete based on multi-scale energy dissipation analysis

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(Technological Sciences) 2024年第3期67卷 863-877页

作者： guo ChengGong li Jie College of Civil Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Shanghai 200092China

This work proposes a unified damage model for concrete within the framework of stochastic damage mechanics. Based on the micro-meso stochastic fracture model(MMSF), the nonlinear energy dissipation process of the microspring from nanoscale to microscale is investigated. In nanoscale, the rate process theory is adopted to describe the crack growth rate;therefore, the corresponding energy dissipation caused by a representative crack propagation can be obtained. The scale gap from nanoscale to microscale is bridged by a crack hierarchy model. Thus, the total energy dissipated by all cracks from the nanoscale to the microscale is gained. It is found that the fracture strain of the microspring can be derived from the above multi-scale energy dissipation analysis. When energy dissipation is regarded as some microdamage to the microspring, the constitutive law of the microspring is no longer linearly elastic, as previously assumed. By changing the expression of the damage evolution law from fracture strain to energy dissipation threshold, the new damage evolution model is derived. The proposed model can not only replicate the original static model but also extend to cases of rate dependence. By deriving the fracture strain under different strain rates, the rate sensitivity of concrete materials can be reflected. The model parameters can be conveniently obtained by identifying them with experimental data. Finally, several numerical examples are presented to verify the proposed model.

关键词： concrete damage model stochastic damage rate dependent energy dissipation

同方期刊数据库

Synergistic effect of gradient Zn content and multiscale particles on the mechanical properties of Al-Zn-Mg-Cu alloys with coupling distribution of coarse-fine grains

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1392-1405页

作者： liangliang Yuan Mingxing guo Yi Wang yun Wang linzhong Zhuang Institute of Effectiveness Evaluation of Flying Vehicle Beijing 100085China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China

This study investigated the influence of graded Zn content on the evolution of precipitated and iron-rich phases and grain struc-ture of the alloys,designed and developed the Al–8.0Zn–1.5Mg–1.5Cu–0.2Fe(wt%)alloy with high strength and *** the increase of Zn content,forming the coupling distribution of multiscale precipitates and iron-rich phases with a reasonable matching ratio and dispersion distribution characteristics is *** phenomenon induces the formation of cell-like structures with alternate distribu-tion of coarse and fine grains,and the average plasticity–strain ratio(characterizing the formability)of the pre-aged alloy with a high strength is up to *** reveal the evolution and influence mechanisms of multiscale second-phase particles and the corresponding high formability mechanism of the *** developed coupling control process exhibits considerable potential,revealing remarkable improvements in the room temperature formability of high-strength Al–Zn–Mg–Cu alloys.

关键词： Al–Zn–Mg–Cu alloy iron-rich phase high formability microstructure mechanisms

Prognostic value of circulating tumor cells combined with neutrophil-lymphocyte ratio in patients with hepatocellular carcinoma

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2024年第2期16卷 372-385页

作者： Jia-li Chen Lu guo Zhen-Ying Wu Kun He Han li Chi Yang yun-Wei Han Department of Oncology The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Department of Ophthalmology The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Clinical Research Institute The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Department of Plastic Surgery Meguiar's Medical Beauty HospitalChengdu 610000Sichuan ProvinceChina

BACKGROUND Circulating tumor cell(CTC)count and neutrophil-to-lymphocyte ratio(NLR)are both closely associated with the prognosis of hepatocellular carcinoma(HCC).AIM To investigate the prognostic value of combining these two indicators in *** Clinical data were collected from patients with advanced HCC who received im-mune therapy combined with targeted therapy at the Department of Oncology,the Affiliated Hospital of Southwest Medical University,Sichuan,China,from 2021 to *** optimal cutoff values for CTC programmed death-ligand 1(PD-L1)(+)>1 or CTC PD-L1(+)≤1 and NLR>3.89 or NLR≤3.89 were evaluated using X-Tile *** were categorized into three groups based on CTC PD-L1(+)counts and NLR:CTC-NLR(0),CTC-NLR(1),and CTC-NLR(2).The relationship between CTC-NLR and clinical variables as well as survival rates was *** Patients with high CTC PD-L1(+)expression or NLR at baseline had shorter median progression-free survival(m-PFS)and median overall survival(mOS)than those with low levels of CTC PD-L1(+)or NLR(Pline CTC-NLR score may indicate low ***-NLR may serve as an effective prognostic indicator for patients with advanced HCC receiving immunotherapy combined with targeted therapy.

关键词： Circulating tumor cells Neutrophil–lymphocyte ratio Hepatocellular carcinoma Prognosis Survival Marker