检索结果-南通市图书馆

International Journal of Minerals,Metallurgy and Materials 2021年第1期28卷 131-141页

作者： Gao-hui Li Li Zhou ling-yun luo Xi-ming Wu Ning Guo State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Shandong Provincial Key Laboratory of Special Welding Technology Harbin Institute of Technology(WeihaiWeihai)264209China

In this study, we used the stop-action technique to experimentally investigate the material flow and microstructural evolution of alclad 2A12-T4 aluminum alloy during refill friction stir spot *** are two material flow components, i.e., the inward-or outward-directed spiral flow on the horizontal plane and the upward-or downward-directed flow on the vertical *** the plunge stage, the flow of plasticized metal into the cavity is similar to that of a stack, whereby the upper layer is pushed upward by the lower *** the refill stage, this is process *** such, there is no obvious vertical plasticized metal flow between adjacent *** leads to the coarsening of S(Al2CuMg) in the thermo-mechanically affected zone and the diminishing of S in the stir *** dynamic recrystallization results in the formation of fine equiaxed grains in the stir zone, but this process becomes difficult in the thermo-mechanically affected zone due to the lower deformation rate and the pinning action of S precipitates on the dislocations and sub-grain boundaries, which leads to a high fraction of low-angle grain boundaries in this zone.

关键词： refill friction stir spot welding aluminum alloy material flow behavior precipitate evolution dislocation configuration

Effect of Sleeve Plunge Depth on Interface/Mechanical Characteristics in Refill Friction Stir Spot Welded Joint

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2020年第4期33卷 551-560页

作者： Guang-Da Sun Li Zhou Ren-Xiao Zhang ling-yun luo Hao Xu Hong-yun Zhao Ning Guo Di Zhang State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Shandong Provincial Key Laboratory of Special Welding Technology Harbin Institute of Technology at WeihaiWeihai 264209China State Key Laboratory of Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

Refill friction stir spot welding was employed to produce 6061-T6 aluminum alloy joints with different sleeve plunge *** interface characteristics of joint-line remnant and hook are investigated by optical and scanning electron *** joint-line remnant consists of primary bonding region and secondary bonding region,and two types of hook can be identified as downward hook and upward *** shear results demonstrate that joint-line remnant and hook make interaction effects on tensile shear *** optimal joint is achieved when sleeve plunge depth was 2.0 mm with the corresponding failure load of 8673.4 *** different types of fracture mode are exhibited in joints produced at different sleeve plunge depths,which are closely related with the morphology of interface characteristics.

关键词： Refill friction stir spot welding Interface characteristics Mechanical properties Fracture behavior

Unveiling the role of hypoxia-inducible factor 2alpha in osteoporosis:Implications for bone health

在线全文

学校读者我要写书评

暂无评论

World Journal of Stem Cells 2024年第4期16卷 389-409页

作者： ling-ling Wang Zhan-Jin Lu Shun-Kui luo yun Li Zhe Yang Hong-yun Lu Department of Gerontology The Fifth Affiliated Hospital of Sun Yat-sen UniversityZhuhai 519000Guangdong ProvinceChina Department of Endocrinology and Metabolism The Fifth Affiliated Hospital of Sun Yat-sen UniversityZhuhai 519000Guangdong ProvinceChina Guangdong Provincial Key Laboratory of Biomedical Imaging The Fifth Affiliated Hospital of Sun Yat-sen UniversityZhuhai 519000Guangdong ProvinceChina Department of Endocrinology and Metabolism Zhuhai People’s Hospital(Zhuhai Clinical Medical College of Jinan Universitythe First Hospital Affiliated with Medical College of Macao University of Science and Technology)Zhuhai 519000Guangdong ProvinceChina

BACKGROUND Osteoporosis(OP)has become a major public health problem *** OP treatments are based on the inhibition of bone resorption,and it is necessary to identify additional treatments aimed at enhancing *** the bone marrow(BM)niche,bone mesenchymal stem cells(BMSCs)are exposed to a hypoxic ***,a few studies have demonstrated that hypoxiainducible factor 2alpha(HIF-2α)is involved in BMSC osteogenic differentiation,but the molecular mechanism involved has not been *** To investigate the effect of HIF-2αon the osteogenic and adipogenic differentiation of BMSCs and the hematopoietic function of hematopoietic stem cells(HSCs)in the BM niche on the progression of *** Mice with BMSC-specific HIF-2αknockout(Prx1-Cre;Hif-2αfl/fl mice)were used for in vivo *** quantification was performed on mice of two genotypes with three interventions:Bilateral ovariectomy,semilethal irradiation,and dexamethasone ***,the hematopoietic function of HSCs in the BM niche was compared between the two mouse *** vitro,the HIF-2αagonist roxadustat and the HIF-2αinhibitor PT2399 were used to investigate the function of HIF-2αin BMSC osteogenic and adipogenic ***,we investigated the effect of HIF-2αon BMSCs via treatment with the mechanistic target of rapamycin(mTOR)agonist MHY1485 and the mTOR inhibitor *** The quantitative index determined by microcomputed tomography indicated that the femoral bone density of Prx1-Cre;Hif-2αfl/fl mice was lower than that of Hif-2αfl/fl mice under the three intervention *** vitro,Hif-2αfl/fl mouse BMSCs were cultured and treated with the HIF-2αagonist roxadustat,and after 7 d of BMSC adipogenic differentiation,the oil red O staining intensity and mRNA expression levels of adipogenesis-related genes in BMSCs treated with roxadustat were decreased;in addition,after 14 d of osteogenic differentiation,BMSCs treated with roxadusta

关键词： Hypoxia-inducible factor-2α Bone marrow niche Bone mesenchymal stem cells Osteoporosis Osteogenic/adipogenic differentiation Mechanistic target of rapamycin signaling pathway

Depressed female cynomolgus monkeys(Macaca fascicularis) display a higher second-to-fourth(2D:4D)digit ratio

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

Zoological Research 2019年第3期40卷 219-225页

作者： Wei Li ling-yun luo Xun Yang Yong He Bin Lian Chao-Hua Qu Qing-Yuan Wu Jian-Guo Zhang Peng Xie Department of Neurology Army Medical Center of PLAChongqing 400042China Institute of Neuroscience Chongqing Medical UniversityChongqing 400016China Chongqing Key Laboratory of Neurobiology of Chongqing Medical University Chongqing 400016China Department of Neurology the Third Affiliated Hospital of Sun Yat-Sen University Yuedong HospitalGuangzhou Guangdong 514700China

This research aimed to provide evidenee of a relationship between digit ratio and depression status in the cynomolgus monkey(Macaca fascicularis).In stable cyno molgus mon key social groups,we selected 15 depressed monkeys based on depressive-like behavioral criteria and 16 normal control mon *** animals were video recorded for two weeks,with the duration and frequency of the core depressive behaviors and 58 other behaviors in 12 behavioral categories then evaluated via behavioral *** ger len gths from the right and left forelimb hands of both groups were measured by X-ray imagi *** ger length and digit ratio comparisons between the two groups were con ducted using Stude nt's *** terms of the durati on of each behavior,signifies nt differences emerged in“Huddling”and five other behavioral categories,including Ingestive,Amicable,Parental,Locomotive,and *** addition to the above five behavioral categories,we found that depressed mon keys spent less time in parental and rubbing back and forth behaviors than the control ***,the 4th fin gers were significantly Ion ger in the left and right hands in the control group relative to the depressed mon *** sec ond?to?fourth(2D:4D)digit ratio in the left and right forelimb hands was significantly lower in the control group tha n that in the depressed *** fin dings revealed significant differences in finger lengths and digit ratios between depressed mon keys and healthy controls,which concords with our view that relatively high fetal testosterone exposure may be a protective factor against developing depressive symptoms(or that low fetal testosterone exposure is a risk factor).

关键词： Fin ger length Digit ratio Major depressive disorder Cynomolgus mon key

Bayesian network-based survival prediction model for patients having undergone post-transjugular intrahepatic portosystemic shunt for portal hypertension

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第13期30卷 1859-1870页

作者： Rong Chen ling luo yun-Zhi Zhang Zhen Liu An-Lin Liu Yi-Wen Zhang Department of Infectious Diseases Second Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China

BACKGROUND Portal hypertension(PHT),primarily induced by cirrhosis,manifests severe symptoms impacting patient *** transjugular intrahepatic portosystemic shunt(TIPS)is a critical intervention for managing PHT,it carries risks like hepatic encephalopathy,thus affecting patient survival *** our knowledge,existing prognostic models for post-TIPS survival in patients with PHT fail to account for the interplay among and collective impact of various prognostic factors on ***,the development of an innovative modeling approach is essential to address this *** To develop and validate a Bayesian network(BN)-based survival prediction model for patients with cirrhosis-induced PHT having undergone *** The clinical data of 393 patients with cirrhosis-induced PHT who underwent TIPS surgery at the Second Affiliated Hospital of Chongqing Medical University between January 2015 and May 2022 were retrospectively *** were selected using Cox and least absolute shrinkage and selection operator regression methods,and a BN-based model was established and evaluated to predict survival in patients having undergone TIPS surgery for *** Variable selection revealed the following as key factors impacting survival:age,ascites,hypertension,indications for TIPS,postoperative portal vein pressure(post-PVP),aspartate aminotransferase,alkaline phosphatase,total bilirubin,prealbumin,the Child-Pugh grade,and the model for end-stage liver disease(MELD)*** on the above-mentioned variables,a BN-based 2-year survival prognostic prediction model was constructed,which identified the following factors to be directly linked to the survival time:age,ascites,indications for TIPS,concurrent hypertension,post-PVP,the Child-Pugh grade,and the MELD *** Bayesian information criterion was 3589.04,and 10-fold cross-validation indicated an average log-likelihood loss of 5.55 with a standard deviation of *** model’s acc

关键词： Bayesian network Cirrhosis Portal hypertension Transjugular intrahepatic portosystemic shunt Survival prediction model

The chemical characteristics of different sodium iron ethylenediaminetetraacetate sources and their relative bioavailabilities for broilers fed with a conventional corn‑soybean meal diet

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

Journal of Animal Science and Biotechnology 2024年第2期15卷 826-843页

作者： Shengchen Wang Bingxin Wu ling Zhu Weiyun Zhang Liyang Zhang We Wu Jiaqi Wu yun Hu Tingting Li Xiaoyan Cui Xugang luo College of Animal Science and Technology Yangzhou UniversityYangzhou 225000People’s Republic of China Mineral Nutrition Research Division State Key Laboratory of Animal NutritionInstitute of Animal ScienceChinese Academy of Agricultural SciencesBeijing 100193China

Background Our previous studies demonstrated that divalent organic iron(Fe)proteinate sources with higher complexation or chelation strengths as expressed by the greater quotient of formation(Qf)values displayed higher Fe bioavailabilities for *** iron ethylenediaminetetraacetate(NaFeEDTA)is a trivalent organic Fe source with the strongest chelating ligand ***,the bioavailability of Fe when administered as NaFeEDTA in broilers and other agricultural animals remains ***,the chemical characteristics of 12 NaFeEDTA products were *** these,one feed grade NaFeEDTA(Qf=2.07×10^(8)),one food grade NaFeEDTA(Qf=3.31×10^(8)),and one Fe proteinate with an extremely strong chelation strength(Fe-Prot ES,Qf value=8,590)were *** bioavailabilities relative to Fe sulfate(FeSO_(4)·7H_(2)O)for broilers fed with a conventional corn-soybean meal diet were evaluated during d 1 to 21 by investigating the effects of the above Fe sources and added Fe levels on the growth performance,hematological indices,Fe contents,activities and gene expressions of Fe-containing enzymes in various tissues of *** NaFeEDTA sources varied greatly in their chemical *** Fe concentration(PI),transferrin saturation(TS),liver Fe content,succinate dehydrogenase(SDH)activities in liver,heart,and kidney,catalase(CAT)activity in liver,and SDH mRNA expressions in liver and kidney increased linearly(P<0.05)with increasing levels of Fe ***,differences among Fe sources were detected(P<0.05)only for PI,liver Fe content,CAT activity in liver,SDH activities in heart and kidney,and SDH mRNA expressions in liver and *** on slope ratios from multiple linear regressions of the above indices on daily dietary analyzed Fe intake,the average bioavailabilities of Fe-Prot ES,feed grade NaFeEDTA,and food grade NaFeEDTA relative to the inorganic FeSO_(4)·7H_(2)O(100%)for broilers were 139%,155%,and 166%,***

关键词： Broilers Chelation strengths Fe-containing enzymes NaFeEDTA Relative bioavailabilities

A Survey of Knowledge Graph Construction Using Machine Learning

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2024年第4期139卷 225-257页

作者： Zhigang Zhao Xiong luo Maojian Chen ling Ma School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China Shunde Innovation School University of Science and Technology BeijingFoshan528399China Beijing Key Laboratory of Knowledge Engineering for Materials Science Beijing100083China

Knowledge graph(KG)serves as a specialized semantic network that encapsulates intricate relationships among real-world entities within a structured *** framework facilitates a transformation in information retrieval,transitioning it from mere string matching to far more sophisticated entity *** this transformative process,the advancement of artificial intelligence and intelligent information services is ***,the role ofmachine learningmethod in the construction of KG is important,and these techniques have already achieved initial *** article embarks on a comprehensive journey through the last strides in the field of KG via machine *** a profound amalgamation of cutting-edge research in machine learning,this article undertakes a systematical exploration of KG construction methods in three distinct phases:entity learning,ontology learning,and knowledge ***,a meticulous dissection of machine learningdriven algorithms is conducted,spotlighting their contributions to critical facets such as entity extraction,relation extraction,entity linking,and link ***,this article also provides an analysis of the unresolved challenges and emerging trajectories that beckon within the expansive application of machine learning-fueled,large-scale KG construction.

关键词： Knowledge graph(KG) semantic network relation extraction entity linking knowledge reasoning

Revealing effect of Al content on oxidation of novel Co-Cr-Nb-W carbide-strengthened superalloy

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

Rare Metals 2024年第9期43卷 4521-4534页

作者： Chen ling Shang-Ping Li Jie Hou He-Li luo Central Iron & Steel Research Institute Beijing GAONA Materials&Technology Co. Ltd.

The high-temperature oxidation behavior of novel Co-Cr-Nb-W carbide-strengthened wear-resistance alloys with different Al contents（1wt%, 2wt% and 3wt%）at 950, 1000 and 1050 °C was thoroughly investigated by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and field emission electron probe analyzer. The porous property of Nb C in-situ oxidation products（Nb2O5, Co Nb2O6and Co4Nb2O9） induces a multi-layered oxide scale with micropores and ***-Cr-Nb-W alloy with 1 wt% Al undergoes catastrophic oxidation and spalling above 1000 °C. The outward transportation of Cr and Co is effectively restrained by a continuous Al2O3scale formed around Nb C in-situ oxidation region when Al content reaches 3 wt%. The β-Co Al in Co-Cr-Nb-W alloy with 3 wt% Al has an oxidation priority over eutectic carbides and the alloy matrix which are both enriched with Cr, thereby preventing the formation of Cr-depletion area and improving the self-healing ability of the oxide film. A slight change in Al content has a remarkable influence on the cooperative effect of Al and Cr and multiplies the antioxidant capacity of Co-Cr-Nb-W alloy above 1000 °C.

关键词： High-temperature oxidation behavior Microstructure Oxidation kinetics Superalloy Wear-resistant alloy

Numerical and experimental investigation on hydraulic-electric rock fragmentation of heterogeneous granite

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2024年第1期34卷 15-29页

作者： Xiaohua Zhu ling He Weiji Liu yunxu luo Youjian Zhang Wuji Tang School of Mechatronic Engineering Southwest Petroleum UniversityChengdu 610500China School of Mechanical Engineering Sichuan University of Science and EngineeringYibin 643002China

Hydraulic-electric rock fragmentation(HERF)plays a significant role in improving the efficiency of high voltage pulse rock ***,the underlying mechanism of HERF remains *** this study,considering the heterogeneity of the rock,microscopic thermodynamic properties,and shockwave time domain waveforms,based on the shockwave model,digital imaging technology and the discrete element method,the cyclic loading numerical simulations of HERF is achieved by coupling electrical,thermal,and solid mechanics under different formation temperatures,confining pressure,initial peak voltage,electrode bit diameter,and loading ***,the HERF discharge system is conducive to the laboratory experiments with various electrical parameters and the resulting broken pits are numerically reconstructed to obtain the geometric *** results show that,the completely broken area consists of powdery rock *** the pre-broken zone,the mineral cementation of the rock determines the transition of type CⅠcracks to type CⅡand type CⅢ***,the peak pressure of the shockwave increased with initial peak voltage but decreased with electrode bit diameter,while the wave front time ***,increasing well depth,formation temperature and confining pressure augment and inhibit HERF,but once confining pressure surpassed the threshold of 60 MPa for 152.40,215.90,and 228.60 mm electrode bits,and 40 MPa for 309.88 mm electrode bits,HERF is ***,for the same kind of rock,the volume and width of the broken pit increase with higher initial peak voltage and rock fissures will promote ***,the electrode drill bit with a 215.90 mm diameter is more suitable for drilling pink *** research contributes to a better microscopic understanding of HERF and provides valuable insights for electrode bit selection,as well as the optimization of circuit parameters for HERF technology.

关键词： Hydraulic-electric rock fragmentation Shockwave Thermodynamics Microcracks Weak Linear Parallel Bond Model

Dietary copper requirement of broilers fed a corn-soybean meal diet during 22—42 d of age

在线全文

学校读者我要写书评

暂无评论

Animal Nutrition 2024年第1期16卷 96-104页

作者： ling Zhu Wei Wu Bingxin Wu yun Hu Liyang Zhang Weiyun Zhang Tingting Li Xiaoyan Cui Feiyu Gao Ding Li Xugang luo Shengchen Wang Poultry Mineral Nutrition Laboratory College of Animal Science and TechnologyYangzhou UniversityYangzhou 225000China Mineral Nutrition Research Division State Key Laboratory of Animal NutritionInstitute of Animal ScienceChinese Academy of Agricultural SciencesBeijing 100193China

This research was to assess the dietary copper(Cu)requirement of broiler chickens fed a practical cornsoybean meal diet during 22—42 d of age.A total of 288 numbered Arbor Acres male broilers at 22 d of age were randomly allotted 6 treatments with 8 replicate cages(6 broilers per cage)per *** were fed a Cu-unsupplemented corn-soybean meal basal diet(control,containing 7.36 mg Cu/kg)or the basal diet added with 3,6,9,12,or 15 mg Cu/kg from CuSO_(4)·5H_(2)O for 21 ***,asymptotic and broken-line models were fitted and the best fitted models were selected to determine dietary Cu *** results revealed that the contents of Cu in serum and liver,m RNA expression levels of Cu-and zinc-containing superoxide dismutase(CuZnSOD)in liver and monoamine oxidase b(MAO B)in heart,as well as protein expression level of CuZnSOD in liver were affected(P<0.05)by supplemental Cu levels,and the above indices varied linearly and quadratically(P<0.05)with increasing Cu *** Cu requirements assessed according to the best fitted broken-line models(P<0.05)of the above indexes were 10.45—13.81 mg/*** was concluded that mRNA expression levels of CuZnSOD in liver and MAO B in heart,as well as liver CuZnSOD protein expression level were new specific sensitive biomarkers for estimating dietary Cu requirements,and the dietary Cu requirement was recommended to be 14 mg/kg to support Cu metabolic needs related to key Cucontaining enzymes in broilers fed the corn-soybean meal diet during 22—42 d of age,which was higher than the dietary Cu requirement(8 mg/kg)for broilers at the corresponding stage suggested by the Chinese Feeding Standard of Chicken.

关键词： Copper Copper content Gene expression of copper-containing enzyme Requirement Broiler

同方期刊数据库