检索结果-南通市图书馆

Comparison of microstructure and heat treatment distortion of gear steels with and without Nb addition

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2021年第4期28卷 488-495页

作者： Guo-qiang Zhang xiao-fei he Qian-zhen Zhang Wen-jun Wang Mao-qiu Wang Institute of Special Steel Central Iron and Steel Research InstituteBeijing 100081China NGC Group Nanjing 211102JiangsuChina Technical Center CITIC Metal GroupBeijing 100027China

In order to research the effect of microalloying Nb,the microstructure and heat treatment distortion of case carburizing steels with and without Nb addition are *** show that a uniform and fine prior austenite grain size was obtained for the steel with the addition of 0.03 wt.%Nb even after being carburized at 980℃for 37 h,resulting in a very deep hardened layer of about 4 *** is an effective microalloying element to hinder austenite grain growth of gears during high-temperature *** calculation and experimental observation of NbC precipitates indicate that fine NbC precipitates have not evidently dissolved at 980℃,and thus they can act as grain refiners due to pinning *** treatment distortion of Nb-added steel is much lower than that of the steel without Nb *** may be contributed to its fine and uniform grain size,which presumably influences stress during martensitic transformation.

关键词： Case hardening steel High-temperature carburizing Grain size heat treatment distortion Microstructure

Effects of garlicin on apoptosis in rat model of colitis

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 Gastroenterology 2005年第29期11卷 4579-4582页

作者： Xi-Ming Xu Jie-Ping Yu xiao-fei he Jun-Hua Li Liang-Liang Yu Hong-Gang Yu Department of Gastroenterology Renmin Hospital Wuhan University Wuhan 430060 Hubei Province China Department of Gastroenterology the Affiliated Hospital of Xianning Medical College Xianning 437100 Hubei Province China

AIM： To investigate the effects of garlicin on apoptosis and expression of bcl-2 and bax in lymphocytes in rat model of ulcerative colitis （UC）. METHODS： healthy adult Sprague-Dawley rats of both sexes, weighing 180±30 g, were employed in the present study. The rat model of UC was induced by 2,4,6-trinitrobenzene sulfonic acid （TNBS） enema. The experimental animals were randomly divided into garlicin treatment group （including high and low concentration）, model control group, and normal control group. Rats in garlicin treatment group and model control group received intracolic garlicin daily at doses of 10.0 and 30.0 mg/kg and equal amount of saline respectively 24 h after colitis model was induced by alcohol and TNBS co-enema. Rats in normal control group received neither alcohol nor only TNBS but only saline enema in this study. On the 28^th d of the experiment, rats were executed, the expression of bd-2 and bax protein was determined immunohistochemically and the apoptotic cells were detected by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate fluorescence nick end labeling （TUNEL） method. At the same time, the rat colon mucosal damage index （CMDI） was calculated. RESULTS： In garlicin treatment group, the positive expression of bcl-2 in lymphocytes decreased and the number of apoptotic cells was more than that in model control group, CMDI was lower than that in model control group. The positive expression of bax in lymphocytes had no significant difference. CONCLUSION： Garlicin can protect colonic mucosa against damage in rat model of UC induced by TNBS enema.

关键词： Garlicin Ulcerative colitis Apoptosis Bcl-2

CT-based radiomics to predict development of macrovascular invasion in hepatocellular carcinoma:A multicenter 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

hepatobiliary & Pancreatic Diseases International 2022年第4期21卷 325-333页

作者： Jing-Wei Wei Si-Rui Fu Jie Zhang Dong-Sheng Gu xiao-Qun Li Xu-Dong Cheng Shuai-Tong Zhang xiao-fei he Jian-Feng Yan Li-Gong Lu Jie Tian Key Laboratory of Molecular Imaging Institute of AutomationChinese Academy of SciencesBeijing 100190China Beijing Key Laboratory of Molecular Imaging Beijing 100190China University of Chinese Academy of Sciences Beijing 100049China Zhuhai Interventional Medical Center Zhuhai Precision Medical CenterZhuhai People’s HospitalZhuhai Hospital of Jinan UniversityZhuhai 519000China Department of Radiology Zhuhai Precision Medical CenterZhuhai People’s HospitalZhuhai Hospital of Jinan UniversityZhuhai 519000China Department of Interventional Treatment Zhongshan City People’s HospitalZhongshan 528400China Department of Radiology Shenzhen People’s HospitalShenzhen 518000China Interventional Diagnosis and Treatment Department Nanfang HospitalSouthern Medical UniversityGuangzhou510000China Department of Radiology Yangjiang People’s HospitalYangjiang 529500China Beijing Advanced Innovation Center for Big Data-Based Precision Medicine School of Medicine and EngineeringBeihang UniversityBeijing 100191China Engineering Research Center of Molecular and Neuro Imaging of Ministry of Education School of Life Science and TechnologyXidian UniversityXi’an 710126China

Background:Macrovascular invasion(MaVI)occurs in nearly half of hepatocellular carcinoma(HCC)patients at diagnosis or during follow-up,which causes severe disease deterioration,and limits the possibility of surgical *** study aimed to investigate whether computed tomography(CT)-based radiomics analysis could help predict development of MaVI in ***:A cohort of 226 patients diagnosed with HCC was enrolled from 5 hospitals with complete MaVI and prognosis ***-based radiomics signature was built via multi-strategy machine learning ***,MaVI-related clinical factors and radiomics signature were integrated to construct the final prediction model(CRIM,clinical-radiomics integrated model)via random forest ***-regression analysis was used to select independent risk factors to predict the time of MaVI ***-Meier analysis was conducted to stratify patients according to the time of MaVI development,progression-free survival(PFS),and overall survival(OS)based on the selected risk ***:The radiomics signature showed significant improvement for MaVI prediction compared with conventional clinical/radiological predictors(Phe curve(AUC)of 0.986 and 0.979 in the training(n=154)and external validation(n=72)datasets,*** presented with excellent generalization with AUC of 0.956,1.000,and 1.000 in each external cohort that accepted disparate CT scanning protocol/***9_fos_InterquartileRange[hazard ratio(HR)=1.98;Phe independent risk *** cox-regression model successfully stratified patients into the high-risk and low-risk groups regarding the time of MaVI development(Phe CT-based quantitative radiomics analysis could enable high accuracy prediction of subsequent MaVI development in HCC with prognostic implications.

关键词： hepatocellular carcinoma Macrovascular invasion Radiomics Computed tomography Prognosis

A novel frameshift mutation in the BCOR gene is associated with oculo-facio-cardio-dental syndrome:a case report

在线全文

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2025年第2期18卷 370-374页

作者： Qiu-Mei Gu Xue-fei he Wen-Zhe xiao Chao Qu Department of Ophthalmology West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina West China Biobank West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Respiratory and Critical Care Medicine Center for High Altitude MedicineInstitutes for Systems GeneticsNational Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Ophthalmology Sichuan Academy of Medical Sciences and Sichuan People’s HospitalChengdu 610072Sichuan ProvinceChina

Dear Editor,Oculo-facio-cardio-dental(OFCD)syndrome is a rare X chromosome-linked dominant genetic disease with multiple system and site *** typical traits shown in this disease are:1)eye abnormalities,notably congenital cataracts,microphthalmia,and secondary glaucoma;2)facial deformities,in particular long and narrow face,high nasal bridge,nasal tip cartilage division,and cleft palate.

关键词： nasal cataract congenital

miRNA-21-5p is an important contributor to the promotion of injured peripheral nerve regeneration using hypoxia-pretreated bone marrow-derived neural crest cells

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第1期20卷 277-290页

作者： Meng Cong Jing-Jing Hu Yan Yu xiao-Li Li xiao-Ting Sun Li-Ting Wang Xia Wu Ling-Jie Zhu xiao-Jia Yang Qian-Ru he fei Ding Hai-Yan Shi School of Medicine Nantong UniversityNantongJiangsu ProvinceChina Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education and Coinnovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Department of Physiology Jiangsu Health Vocational CollegeNanjingJiangsu ProvinceChina Department of Pathology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina

Our previous study found that rat bone marrow–derived neural crest cells(acting as Schwann cell progenitors)have the potential to promote long-distance nerve ***-based therapy can enhance peripheral nerve repair and regeneration through paracrine bioactive factors and intercellular ***,the complex contributions of various types of soluble cytokines and extracellular vesicle cargos to the secretome remain *** investigate the role of the secretome and extracellular vesicles in repairing damaged peripheral nerves,we collected conditioned culture medium from hypoxia-pretreated neural crest cells,and found that it significantly promoted the repair of sensory neurons damaged by oxygen-glucose *** mRNA expression of trophic factors was highly expressed in hypoxia-pretreated neural crest *** performed RNA sequencing and bioinformatics analysis and found that miR-21-5p was enriched in hypoxia-pretreated extracellular vesicles of neural crest ***,to further clarify the role of hypoxia-pretreated neural crest cell extracellular vesicles rich in miR-21-5p in axonal growth and regeneration of sensory neurons,we used a microfluidic axonal dissociation model of sensory neurons in vitro,and found that hypoxia-pretreated neural crest cell extracellular vesicles promoted axonal growth and regeneration of sensory neurons,which was greatly dependent on loaded ***,we constructed a miR-21-5p-loaded neural conduit to repair the sciatic nerve defect in rats and found that the motor and sensory functions of injured rat hind limb,as well as muscle tissue morphology of the hind limbs,were obviously *** findings suggest that hypoxia-pretreated neural crest extracellular vesicles are natural nanoparticles rich in ***-21-5p is one of the main contributors to promoting nerve regeneration by the neural crest cell *** helps to explain the mechanism of action of the secretome and e

关键词： axotomy cell-free therapy conditioned medium extracellular vesicles hypoxic preconditioning microRNA oxygen-glucose deprivation peripheral nerve injury Schwann cell precursors

在线全文

学校读者我要写书评

暂无评论

电离层氧离子83.4 nm辐射计算方法

地球物理学报 2017年第9期60卷 3308-3314页

作者：刘鑫宇张效信何飞陈波中国科学院长春光学精密机械与物理研究所长春130033 中国科学院大学大珩学院北京100049 中国气象局国家空间天气重点开放实验室国家空间天气监测预警中心北京100081 中国科学院地球与行星物理重点实验室中国科学院地质与地球物理研究所北京100029 中国科学院大学地球科学学院北京100049

氧离子83.4 nm辐射是由氧离子辐射跃迁产生的,是电离层极紫外日辉辐射中辐射强度较高的信号之一.从空间对其进行成像为高层大气状态的监测提供了一种强有力的方法.为了准确的描述辐射强度的分布情况,本文在MSISE-00大气模型下,用AURIC... 详细信息

氧离子83.4 nm辐射是由氧离子辐射跃迁产生的,是电离层极紫外日辉辐射中辐射强度较高的信号之一.从空间对其进行成像为高层大气状态的监测提供了一种强有力的方法.为了准确的描述辐射强度的分布情况,本文在MSISE-00大气模型下,用AURIC计算氧离子83.4 nm辐射的初始体辐射率、电离层氮气分子、氧气分子以及氧原子的密度分布,接着,用Chapman函数生成氧离子密度分布,计算共振散射作用下的体辐射率.然后,给出在不同的初始辐射率情况下,沿天底方向观测的辐射强度对比.最后,与Anderson的计算结果作了两组对比,指出由电子碰撞产生的初始体辐射率占比提高16%,总的辐射强度会提高30%.本文的工作为低热层大气氧离子密度和光电子通量的探测提供支持,这对电离层电子密度反演具有理论意义.

关键词：大气光学日辉辐射体辐射率电离层

Positive effect of Mo on mechanical properties of a Ni-42W-10Co-xMo medium heavy alloy

在线全文

学校读者我要写书评

暂无评论

China Foundry 2025年第1期22卷 108-116页

作者： Guo-xin Cao Jian-xin Dong Yong-sheng he he Jiang Fang Hao Zhi-hua Nie Teng-fei Ma Bao-quan Fu School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Xi'an Superalloy Technology Co. Ltd.Xi’an 710299China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Air-driven Equipment Technology of Zhejiang Province Quzhou UniversityQuzhou 324000ZhejiangChina

In this study,a novel Ni-W-Co-Mo medium heavy alloy(MHA)was designed to improve its mechanical strength via Mo *** the Ni-42W-10Co-x Mo alloy series,where x represents the weight percent of Mo and varies between 0,1,2,5,and 10,the microstructure transitions from a dendritic structure to a hypo-eutectic structure as the Mo content increases from 0 to 5wt.%.Moreover,as the Mo content increases from 0 to 10wt.%,the distribution of theμ-phase shifts from being individually dispersed to forming aggregates,and its volume fraction rises from 0.5%to 7.9%.Notably,theμ-phase evolves into an eutectic microstructure,which helps in minimizing the segregation of *** change is accompanied by a substantial enhancement in mechanical properties;specifically,the compressive yield strength at room temperature increases from 350 MPa to 646 MPa,indicating a significant 85%***,the microhardness increases from 230 HV to 304 *** dynamics simulations further reveal that the strengthening mechanism of Ni-42W-10Co-x Mo alloys is Mo-induced solid solution strengthening and precipitation strengthening.

关键词： medium-heavy alloys Ni-based alloy mechanical properties solid solution strengthening precipitation strengthening

同方期刊数据库

Copper-catalyzed C–C bond cleavage coupling with C≡N bond formation toward mild synthesis of lignin-based benzonitriles

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2025年第5期151卷 505-515页

作者： Qi Luo Shenglong Tian Qian Qiang fei song Wentao Su Haiyan he Qingda An Changzhi Li Liaoning Key Lab of Lignocellulose Chemistry and BioMaterials Liaoning Collaborative Innovation Center for Lignocellulosic BiorefinerySchool of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalian 116034China CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Science Beijing 100049China

N-participated lignin depolymerization is of great importance for the transformation of waste lignin into value-added *** vast majority of developed strategies employ organic amines as nitrogen source,and considerablemethods rely on excessive use of strong base,which suffers severe environmental ***,benzonitrile derivatives are synthesized from oxidized ligninβ-O-4 model compounds in the presence of solid nitrogen source(NH_(4))_(2)CO_(3)under mild,base-free conditions over commercially available copper *** studies suggest the transformation undergoes a one-pot,highly coupled cascade reaction path involving oxidative C-C bond cleavage and in-situ formation of C≡N *** which,Cu(OAc)2 catalyzes the transfer of hydrogen from C_(β)(C_(β)-H)to C_(α),leading to the cleavage of C_(α)-C_(β)bonds to offer benzaldehyde derivative,this intermediate then reacts in-situ with(NH_(4))_(2)CO_(3)to afford the targeted aromatic nitrile *** iodide(TBAI),acting as a promoter,plays a key role in breaking the C_(α)-C_(β)bonds to form the intermediate benzaldehyde *** this protocol,the feasibility of the production of value-added syringonitrile from birchwood lignin has been *** transformation provides a sustainable approach to benzonitrile chemicals from renewable source of lignin.

关键词： Lignin β-O-4 model compounds Benzonitrile derivatives Copper catalyst Mild conditions

Taming of trinitromethyl-oxadiazole to access high density and high oxygen balance via a dual modulation strategy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology(防务技术) 2025年第1期43卷 142-149页

作者： Jinya Zhang Teng fei Jingwei Meng Jinxiong Cai Lei Zhang Siping Pang Chunlin he School of Materials Science&Engineering Beijing Institute of TechnologyBeijing 100081China Experimental Center of Advanced Materials School of Materials Science&EngineeringBeijing Institute of TechnologyBeijing 100081China hongqing Innovation Center Beijing Institute of TechnologyChongqing 401120China

Energetic compounds bearing the trinitromethyl group are garnering broad attraction as potential candidates for a new generation of high energy dense *** this work,an effective dual modulation strategy involving both molecular isomerization and crystal morphology control was employed to design and optimize trinitromethyl-oxadiazole with improved comprehensive *** this dual strategy,3,5-bis(trinitromethyl)-1,2,4-oxadiazole(3)was synthesized,resulting in the formation of two distinct crystal morphologies(needle and sheet)corresponding to two crystal forms(3-a and3-b).Encouragingly,while maintaining ultra-high oxygen balance(21.73%),3 achieves impressive densities(1.97-1.98 g/cm^(3)).To our knowledge,the density of 1.98 g/cm^(3)for 3-a sets a new record among that of nitrogen-rich monocyclic ***,practical crystal morphology prediction was creatively introduced to guide the experimental crystallization conditions of 3,increasing the impact sensitivity and friction sensitivity from 1 J to 80 N(3-a)to 10 J and 240 N(3-b),***,the crystal structural analyses and theoretical calculations were conducted to elucidate the reasons of differences between 3-a and 3-b in density and *** work provides an efficient strategy to enhance performance of trinitromethyl derivatives,broadening the path and expanding the toolbox for energetic materials.

关键词： Energetic materials High oxygen balance High density Dual modulation Trinitromethyl group