检索结果-南通市图书馆

Effect of tungsten carbide particles on microstructure and mechanical properties of Cu alloy composite bit matrix

Journal of Iron and Steel Research(International) 2024年第2期31卷 519-530页

作者： Ding-qian Dong Feng-yuan He Xin-hui Chen Hui Li Kai-hua Shi Hui-wen Xiong Xin Xiang Li Zhang College of Mechanical Engineering Sichuan University of Science and EngineeringZigong643000SichuanChina State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083HunanChina Zigong Cemented Carbide Co. Ltd.Zigong643011SichuanChina Material Corrosion and Protection Key Laboratory of Sichuan Province Sichuan University of Science and EngineeringZigong643000SichuanChina

Copper alloy composite bit matrix was prepared by pressureless vacuum infiltration,using at least one of the three kinds of tungsten carbide particles,for example,irregular cast tungsten carbide,monocrystalline tungsten carbide and sintered reduced tungsten carbide *** effects of powder particle morphology,particle size and mass fraction of tungsten carbide on the microstructure and mechanical properties of copper alloy composite were investigated by means of scanning electron microscopy,X-ray diffraction and abrasive wear test in *** results show that tungsten carbide morphology and particle size have obvious effects on the mechanical properties of copper alloy *** tungsten carbide partially dissolved in the copper alloy binding phase,and layers of Cu_(0.3)W_(0.5)Ni_(0.1)Mn_(0.1)C phase with a thickness of around 8–15μm were formed on the edge of the cast tungsten *** 45%irregular crushed fine cast tungsten carbide and 15%monocrystalline cast tungsten carbide were used as the skeleton,satisfactory comprehensive performance of the reinforced copper alloy composite bit matrix was obtained,with the bending strength,impact toughness and hardness reaching 1048 MPa,4.95 J/cm^(2) and 43.6 HRC,*** main wear mechanism was that the tungsten carbide particles firstly protruded from the friction surface after the copper alloy matrix was worn,and then peeled off from the matrix when further wear occurred.

关键词： Polycrystalline diamond compact Pressureless vacuum infiltration Copper alloy composite bit matrix Microstructure characterization Abrasive wear behavior

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

Development and validation of a model integrating clinical and coronary lesion-based functional assessment for longterm risk prediction in PCI patients

引用

Journal of Geriatric Cardiology 2024年第1期21卷 44-63页

作者： Shao-Yu WU Rui ZHANG Sheng yuan Zhong-Xing CAI Chang-Dong guan Tong-Qiang ZOU Li-Hua XIE Ke-Fei DOU State Key Laboratory of Cardiovascular Disease BeijingChina Cardiometabolic Medicine Center Fu Wai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Catheterization Laboratories Fu Wai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Cardiology Fu Wai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

OBJECTIVES To establish a scoring system combining the ACEF score and the quantitative blood flow ratio(QFR) to improve the long-term risk prediction of patients undergoing percutaneous coronary intervention(PCI).METHODS In this population-based cohort study, a total of 46 features, including patient clinical and coronary lesion characteristics, were assessed for analysis through machine learning models. The ACEF-QFR scoring system was developed using 1263consecutive cases of CAD patients after PCI in PANDA Ⅲ trial database. The newly developed score was then validated on the other remaining 542 patients in the *** In both the Random Forest Model and the Deep Surv Model, age, renal function(creatinine), cardiac function(LVEF)and post-PCI coronary physiological index(QFR) were identified and confirmed to be significant predictive factors for 2-year adverse cardiac events. The ACEF-QFR score was constructed based on the developmental dataset and computed as age(years)/EF(%) + 1(if creatinine ≥ 2.0 mg/d L) + 1(if post-PCI QFR ≤ 0.92). The performance of the ACEF-QFR scoring system was preliminarily evaluated in the developmental dataset, and then further explored in the validation dataset. The ACEF-QFR score showed superior discrimination(C-statistic = 0.651;95% CI: 0.611-0.691, P < 0.05 versus post-PCI physiological index and other commonly used risk scores) and excellent calibration(Hosmer–Lemeshow χ^(2)= 7.070;P = 0.529) for predicting 2-year patient-oriented composite endpoint(POCE). The good prognostic value of the ACEF-QFR score was further validated by multivariable Cox regression and Kaplan–Meier analysis(adjusted HR = 1.89;95% CI: 1.18–3.04;log-rank P < 0.01) after stratified the patients into high-risk group and low-risk *** An improved scoring system combining clinical and coronary lesion-based functional variables(ACEF-QFR)was developed, and its ability for prognostic prediction in patients with PCI was further validated to be signi

关键词： patients coronary prediction

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

Fundamentals and application in phytoremediation of an efficient arsenate reducing bacterium Pseudomonas putida ARS1

引用

Journal of Environmental Sciences 2024年第3期137卷 237-244页

作者： Ze-wen Wang guang Yang Jian Chen Yaoyu Zhou Avelino Nunez Delgado Hui-Ling Cui Gui-Lan Duan Barry P.Rosen Yong-guan Zhu Henan Institute of Advanced Technology Zhengzhou UniversityZhengzhou 450052China State Key Lab of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Department of Cellular Biology and Pharmacology Florida International UniversityHerbert Wertheim College of MedicineMiamiFL33199USA University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China College of Resources and Environment Hunan Agricultural UniversityChangsha 410128China Department of Soil Science and Agricultura Chemistry Engineering Polytechnic SchoolUniversity of Santiago de CompostelaCampus Univ.s/n27002LugoSpain

Arsenic is a ubiquitous environmental ***-mediated arsenic biotransformations significantly infuence arsenic mobility and *** transformations by soil and aquatic organisms have been well documented,while little is known regarding effects due to endophytic *** endophyte Pseudomonas putida ARS1 was isolated from rice grown in arsenic contaminated *** ARS1 shows high tolerance to arsenite(As(Ⅲ))and arsenate(As(V)),and exhibits efficient As(V)reduction and As(Ⅲ)effux *** exposed to 0.6 mg/L As(V),As(V)in the medium was completely converted to As(Ⅲ)by *** ARS1 within 4 *** sequencing showed that *** ARS1 has two chromosomal arsenic resistance gene clusters(arsRCBH)that contribute to efficient As(V)reduction and As(Ⅲ)effux,and result in high resistance to *** globosa is a strong arsenic accumulator with high potential for arsenic phytoremediation,which takes up As(Ⅲ)more efficiently than As(V).Co-culture of *** ARS1 and *** enhanced arsenic accumulation in *** by 69%,and resulted in 91%removal of arsenic(at initial concentration of 0.6 mg/L As(V))from water within 3 *** study provides a promising strategy for in situ arsenic phytoremediation through the cooperation of plant and endophytic bacterium.

关键词： Arsenic Pseudomonas putida Arsenate reduction Endophyte Wolffia globosa Phytoremediation

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

Mycoplasma hominis Pneumonia Presented as a Cavitary Mass with a Halo Sign in an Immunocompetent Adult Male:A Case Report

引用

Infectious Diseases & Immunity 2024年第3期4卷 142-145页

作者： Pan-Pan Xie Yao Yao Ning Yang wen-Kai Niu Xin yuan Department of Respiratory and Critical Care Diseases Senior Department of Infectious Diseasesthe Fifth Medical Center of Chinese PLA General HospitalNational Clinical Research Center for Infectious DiseasesBeijing 100039China Anhui Medical University PLA 307 Clinical College Beijing 100039China.

Mycoplasma hominis is an opportunistic microorganism that colonizes the genitourinary tract and causes genitourinary ***,pulmonary infections caused by *** have rarely been reported in immunocompetent ***,we report a rare case of an immunocompetent adult male with *** pneumonia who presented with multiple pulmonary nodules that progressed to a cavitary mass with a halo *** presence of *** infection was confirmed using multiplex polymerase chain reaction(mPCR)of the bronchoalveolar lavage *** patient demonstrated no response to the initial levofloxacin therapy;however,the symptoms subsequently improved after the administration of *** may be an underestimated causative agent of community-acquired pneumonia of unknown etiology in immunocompetent adults,and the involvement of the organism should be especially suspected in sexually active *** diagnostic methods,such as mPCR,can be used to identify the etiology of atypical *** antibiotics are crucial for effective treatment.

关键词： M.hominis Halo sign Cavitary pneumonia Extragenital infections Case report

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

Intravitreal injection of conbercept for diabetic macular edema complicated with diabetic nephropathy

引用

International Journal of Ophthalmology(English edition) 2024年第2期17卷 304-310页

作者： yuan-Zhang Zhu Zhi-Zhi Dou wen-Ying Wang Qing-Yue Ma wen-Dan Yi Ning-Ning Yao Yi-Chong Liu Xiao-Di Gao Qian Zhang wen-Juan Luo Department of Ophthalmology the Affiliated Hospital of Qingdao UniversityQingdao 266000Shandong ProvinceChina

AIM:To observe the therapeutic effect of conbercept on diabetic macular edema(DME)complicated with diabetic nephropathy(DN).METHODS:In this retrospective study,54 patients(54 eyes)that diagnosed as DME from January 2017 to October 2021 were *** patients were divided into two groups:DME patients with DN(25 eyes),and DME patients without DN(29 eyes).General conditions were collected before treatment,laboratory tests include fasting blood glucose,HbA1c,microalbumin/creatinine,serum *** coherence tomography(OCT)was used to check the ellipsoidal zone(EZ)and external limiting membrane(ELM)*** macular thickness(CMT),best corrected visual acuity(BCVA),and retinal hyperreflective foci(HF)as well as numbers of injections were ***:There were significant differences between fasting blood glucose,HbA1c,serum creatinine,urinary microalbumin/creatinine,and estimated glomerular filtration rate(eGFR)between the two groups(all P<0.05).EZ and ELM continuity in the DME+DN group was worse than that in the DME group(P<0.05).BCVA(logMAR)in the DME group was significantly better than that in the DME+DN group at the same time points during treatment(all P<0.05).CMT and HF values were significantly higher in the DME+DN group than that in the DME group at the all time points(all P<0.05)and significantly decreased in both groups with time during *** 6mo after treatment,the mean number of injections in the DME+DN and DME group was 4.84±0.94 and 3.79±0.86,***:Conbercept has a significant effect in short-term treatment of DME patients with or without DN,and can significantly ameliorate BCVA,CMT and the number of HF,treatment efficacy of DME patients without DN is better than that of DME patients with DN.

关键词： conbercept diabetic nephropathy diabetic macular edema optical coherence tomography

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

Fe/S oxidation-coupled arsenic speciation transformation mediated by AMD enrichment culture under different pH conditions

引用

Journal of Environmental Sciences 2024年第3期137卷 681-700页

作者： Yu-hang Zhou Wei-xi Huang Zhen-yuan Nie Hong-chang Liu Yue Liu Can Wang Jin-lan Xia wen-sheng Shu Key Lab of Biometallurgy of Ministry of Education of China School of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China School of Life Sciences South China Normal UniversityGuangzhou 510631China

Arsenic(As)speciation transformation in acid mine drainage(AMD)is comprehensively affected by biological and abiotic factors,such as microbially mediated Fe/S redox reactions and changes in environmental conditions(pH and oxidation-reduction potential).However,their combined impacts on arsenic speciation transformation remain poorly ***,we explored arsenic transformation and immobilization during pyrite dissolution mediated by AMD enrichment culture under different acidic pH *** results for incubation and mineralogical transformation of solid residues show that in the presence of AMD enrichment culture,pH 2.0,2.5,and 3.0 are more conducive to the formation of jarosites and ferric arsenate,which could immobilize high quantities of dissolved arsenic by adsorption and *** pH conditions significantly affect the initial adsorption of microbial cells to the minerals and the evolution of microbial community structure,further infuencing the biodissolution of pyrite and the release and oxidation process of Fe/*** results of Fe/S/As speciation transformation of the solid residues show that the transformation of Fe,S,and As in solution is mainly regulated by pH and potential values,which imposed significantly different effects on the formation of secondary minerals and thus arsenic oxidation and *** above results indicated that arsenic transformation is closely related to the Fe/S oxidation associated with pyrite bio-oxidation,and this correlation is critically regulated by the pH conditions of the system.

关键词： Acid mine drainage(AMD) pH conditions Fe/S/As speciation transformation Microbial community structure

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

Insight study of rare earth elements in PM_(2.5)during five years in a Chinese inland city:Composition

引用

Journal of Environmental Sciences 2024年第4期138卷 439-449页

作者： Yi-wen Shen Chang-Xian Zhao Hao Zhao Shuo-Fei Dong Qi Guo Jiao-Jiao Xie Mei-Ling Lv Chun-Gang yuan Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control Department ofEnvironmental Science&EngineeringNorth China Electric Power UniversityBaoding 071000China MOE Key Laboratory of Resources and Environmental Systems Optimization College of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206China Agilent Technologies Co.Ltd.(China) Beijing 100102China

The booming development of rare earth industry and the extensive utilization of its products accompanied by urban development have led to the accelerated accumulation of rare earth elements(REEs)as emerging pollutants in atmospheric *** this study,the variation of REEs in PM_(2.5)with urban(a non-mining city)transformation was investigated through five consecutive years of sample *** compositional variability and provenance contribution of REEs in PM_(2.5)were characterized,and the REEs exposure risks of children and adults via inhalation,ingestion and dermal absorption were also *** results showed an increase in the total REEs concentration from 46.46±35.16 mg/kg(2017)to 81.22±38.98 mg/kg(2021)over the five-year period,with Ce and La making the largest *** actual increment of industrial and traffic emission source among the three pollution sources was 1.34 ng/m^(3).Coal combustion source displayed a downward *** was the main exposure pathway for REEs in PM_(2.5)for both children and *** contributed the most to the total intake of REEs in PM_(2.5)among the population,followed by La and *** exposure risks of REEs in PM_(2.5)in the region were relatively low,but the trend of change was of great *** was strongly recommended to strengthen the concern about traffic-related non-exhaust emissions of particulate matter.

关键词： Rare earth elements Exposure risks Pollution sources Traffic-related non-exhaust emissions

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

Light-induced stepped thermal relaxation in a Hofmann-type metal-organic framework

引用

Science China Chemistry 2024年第6期67卷 1983-1989页

作者： wen Cui Wei-Wei Wu Ze-Yu Ruan Yan-Cong Chen guang-Jun Zeng guan-Xi Chen Si-Guo Wu Zhao-Ping Ni Ming-Liang Tong Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistryInstitute of Green Chemistry and Molecular EngineeringGuangdong Basic Research Center of Excellence for Functional Molecular EngineeringSun Yat-sen UniversityGuangzhou510275China

Spin-crossover(SCO)materials with light-induced multistability have potential applications in multi-addressable opto-magnetic memory devices and multiple ***,we reported a three-dimensional Hofmann-type metal-organic framework(MOF)[Fe(bpy){Pt(CN)_(4)}]·coumarin(1·coumarin,bpy=4,4′-bipyridine),which exhibits an incomplete and hysteretic SCO *** importantly,the light-induced stepped thermal relaxation(LISTR)with obvious magnetic plateau for a hidden intermediate spin state is firstly *** hidden spin state is also observed for the first time in the thermal relaxation after light-assisted spin state annealing(LASSA).Meanwhile,an extremely rare bi-directional light-induced excited spin-state trapping(LIESST)with the highest reverse-LIESST temperature is ***,five spin states can be captured in 1·coumarin and the tristability can be modulated below 102 K through the excitation-relaxation ***,the light-and temperatureinduced multistability provides a new strategy for developing multistable materials.

关键词： light magnetic multistability iron metal-organic framework spin-crossover

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

Development and validation of a novel non-invasive test for diagnosing nonalcoholic fatty liver disease in Chinese children

引用

World Journal of Pediatrics 2024年第4期20卷 413-421页

作者： Zhe-wen Qin Qian-Nan Ren Hong-Xi Zhang Ya-Ru Liu Ke Huang Wei Wu guan-Ping Dong Yan Ni Jun-Fen Fu Division of Endocrinology National Clinical Research Center for Child HealthNational Children’s Regional Medical CenterThe Children’s HospitalDepartment of EndocrinologyNational Clinical Research Center for Child HealthNational Children’s Regional Medical CenterThe Children’s HospitalZhejiang University School of MedicineHangzhou310052China

With the exploding prevalence of obesity,many children are at risk of developing nonalcoholic fatty liver *** anthropometric and laboratory parameters,our study aimed to develop a model to quantitatively evaluate liver fat content(LFC)in children with *** A well-characterized cohort of 181 children between 5 and 16 years of age were recruited to the study in the Endocrinology Department as the derivation *** external validation cohort comprised 77 *** assessment of liver fat content was performed using proton magnetic resonance *** and laboratory metrics were measured in all subjects.B-ultrasound examination was carried out in the external validation *** Kruskal-Wallis test,Spearman bivariate correlation analyses,univariable linear regressions and multivariable linear regression were used to build the optimal predictive *** The model was based on indicators including alanine aminotransferase,homeostasis model assessment of insulin resistance,triglycerides,waist circumference and Tanner *** adjusted R^(2)of the model was 0.589,which presented high sensitivity and specificity both in internal[sensitivity of 0.824,specificity of 0.900,area under curve(AUC)of 0.900 with a 95%confidence interval:0.783–1.000]and external validation(sensitivity of 0.918 and specificity of 0.821,AUC of 0.901 with a 95%confidence interval:0.818–0.984).Conclusions Our model based on five clinical indicators was simple,non-invasive,and inexpensive;it had high sensitivity and specificity in predicting LFC in ***,it may be useful for identifying children with obesity who are at risk for developing nonalcoholic fatty liver disease.

关键词： Biochemical markers Children Magnetic resonance spectroscopy Nonalcoholic fatty liver disease Pediatric obesity

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

Dietary supplementation of benzoic acid and essential oils combination enhances intestinal resilience against LPS stimulation in weaned piglets

引用

Journal of Animal Science and Biotechnology 2024年第2期15卷 878-897页

作者： Chang Cui Yulong Wei Yibo Wang wen Ma Xiaoyu Zheng Jun Wang Ziwei Ma Caichi Wu Licui Chu Shihai Zhang Wutai guan Fang Chen guangdong Provincial Key Laboratory of Animal Nutrition Control College of Animal ScienceSouth China Agricultural UniversityGuangzhou 510642China College of Animal Science and National Engineering Research Center for Breeding Swine Industry South China Agricultural UniversityGuangzhou 510642China guangdong Laboratory for Lingnan Modern Agriculture South China Agricultural UniversityGuangzhou 510642China

Background The benefits of combining benzoic acid and essential oils(BAO)to mitigate intestinal impairment during the weaning process have been well established,while the detailed underlying mechanism has not been fully *** research has primarily focused on the reparative effects of BAO on intestinal injury,while neglecting its potential in enhancing intestinal stress *** In this study,we investigated the pre-protective effect of BAO against LPS-induced stress using a modified experimental *** were pre-supplemented with BAO for 14 d,followed by a challenge with LPS or saline to collect blood and intestinal *** Our findings demonstrated that BAO supplementation led to significant improvements in piglets’final weight,average daily gain,and feed intake/body gain ***,BAO supplementation positively influenced the composition of intestinal microbiota,increasing beneficial Actinobacteriota and Alloprevotella while reducing harmful Desulfobacterota,Prevotella and ***,BAO supplementation effectively mitigated oxidative disturbances and inflammatory responses induced by acute LPS *** was evidenced by elevated levels of T-AOC,SOD,and GSH,as well as decreased levels of MDA,TNF-α,and IL-6 in the ***,piglets subjected to LPS challenge and pre-supplemented with BAO exhibited significant improvements in intestinal morphological structure and enhanced integrity,as indicated by restored expression levels of Occludin and Claudin-1 compared to the non-supplemented *** analysis revealed that BAO supplementation enhanced the jejunal antioxidative capacity by increasing GSH-Px levels and decreasing MDA levels under the LPS challenge and stimulated the activation of the Nrf2 signaling ***,the reduction of TLR4/NF-κB/MAPK signaling pathways activation and proinflammatory factor were also observed in the jejunal of those piglets fed with ***

关键词： Anti-stress Benzoic acid Essential oils Intestine LPS Weaned piglets

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

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：