检索结果-南通市图书馆

Tungsten 2024年第2期6卷 382-393页

作者： Xiang Chen Yuan Sun Long Wang Xin Qu yan Zhao Hong-Wei Xie Di-hua Wang hua-Yi Yin Key Laboratory for Ecological Metallurgy of Multimetallic Mineral of Ministry of Education School of MetallurgyNortheastern UniversityShenyang 110819China Institute of Metal Research Chinese Academy of ScienceShenyang 110016China School of Resource and Environmental Science Wuhan UniversityWuhan 430072China

Integrating electrochemical reduction of CO_(2)and electrochemical oxidation to recycle degraded superalloys is a promising solution to ease resource scarcity and safeguard environmental ***,we propose an electrochemical technique for the conversion of bulk superalloy scraps and CO_(2)into oxide powder at the anode and solid carbon at the cathode,*** particular,a borax-modifi ed CaCl_(2)-based molten salt electrolyte is used for enhancing the electrochemical oxidation of superalloy *** a temperature of 700℃and a voltage of 2.8 V,90.55 wt.%of alloy scraps were oxidized in a molten CaCl_(2)–NaCl–CaCO_(3)–Na_(2)B_(4)O_(7)with an acid–base ratio(K_(a/b))of *** synergy of Cl−and B_(4)O_(7)2−of electrolyte prevents the passivation of the alloy anode and enables continuous ***,the Ni and Co in the anode products are recovered by sulfation roasting with recovery efficiencies of 85.58%and 95.27%for Ni and Co,***,modulating the alkalinity of the electrolyte for enhancing oxidation/pulverization of alloy scrap anode provides new insight into electrochemically recovering superalloy scraps.

关键词： Superalloy scraps Recycling Molten salt Alkalinity Electrochemical oxidation Cobalt

Exploring the effect of cooling rate on non-isothermal crystallization of copolymer polypropylene by fast scanning calorimetry

在线全文

学校读者我要写书评

暂无评论

China Foundry 2024年第4期21卷 379-386页

作者： yang Liao Ye-yuan Hu Kosuke Ikeda Ryoji Okabe Rui-fen Wu Ryota Ozaki qing-yan Xu Key Laboratory for Advanced Materials Processing Technology School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Composite Laboratory Research&Innovation Center Mitsubishi Heavy Industries Ltd.Nagasaki 8510392Japan

Polypropylene is commonly used as a binder for ceramic injection molding,and rapid cooling is often encountered during ***,the crystallization behavior of polypropylene shows a strong dependence on cooling rate due to its semi-crystalline ***,the influence of cooling rate on the quality of final product cannot be *** this study,the fast differential scanning calorimetry(FSC)test was performed to study the influence of cooling rate on the non-isothermal crystallization behavior and non-isothermal crystallization kinetics of a copolymer polypropylene(PP BC03B).The results show that the crystallization temperatures and crystallinity decrease as the cooling rate *** addition,two exothermic peaks occur when cooling rate ranges from 30 to 300 K·s^(-1),indicating the formation of another crystal ***,Ozawa and Mo equations were used to explore the non-isothermal crystallization kinetics,and it can be concluded that the Mo method is suitable for this study.

关键词： cooling rate crystallization temperature crystallinity non-isothermal crystallization kinetics FSC copolymer polypropylene

Exploring a new path of green and efficient utilization of sinter return fine to produce composite pellets

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第7期31卷 1610-1622页

作者： yan-biao Chen Wen-guo Liu Hao Guo Jing-song Wang qing-guo Xue Hai-bin Zuo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China MCC Capital Engineering and Research Incorporation Limited Beijing 100176China

Efficient utilization of sinter return fine is an important measure to reduce cost,increase efficiency,save energy and reduce emission.A new path of green and efficient utilization of return fine was proposed to produce composite *** metallurgical properties of composite pellets under the condition of hydrogen-rich blast furnace were *** experimental results indicate that the coated concentrate was consolidated for the composite pellets through normal Fe_(2)O_(3) *** the surface of core return fine,the liquid phase formed due to its low-melting point,assimilated the adjacent concentrate,and then consolidated with the temperature *** with regular pellets,the com-pressive strength and reduction swelling index of composite pellets were decreased,but the reducibility index and softening-melting properties were *** addition,the reduction degradation index of composite pellets was sig-nificantly higher than that of ***,adding composite pellets was conducive to indirect reduction in blast furnace,reducing fuel ratio and improving production *** to the effect of the roasting system on the metallurgical properties,the roasting temperature and time were determined as 1250℃and 30 min,*** composite pellets can be produced under the traditional pelletizing process.

关键词： Sinter Return fine Composite pellet Roasting system Metallurgical property Hydrogen-rich blast furnace

Clinically significant changes in anal sphincter hiatal area in patients with gestational diabetes mellitus and pelvic organ prolapse

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 Diabetes 2024年第8期15卷 1726-1733页

作者： qing-Hong Wang Li-hua Liu hua Ying Ming-Xu Chen Chang-Jiang Zhou Hui Li Department of Sonography People's Hospital Affiliated to Shandong First Medical UniversityJinan 271100Shandong ProvinceChina Department of Obstetrics and Gynecology People's Hospital Affiliated to Shandong First Medical UniversityJinan 271100Shandong ProvinceChina

BACKGROUND The prevalence of pelvic organ prolapse(POP)increases with age and ***,the prevalence of POP among women aged 20 to 39 is 9.7%,while it rises to 49%among women over 80 years ***,as the number of deliveries increases,the prevalence of POP also rises accordingly,with a rate of 12.8%for women with one delivery history,18.7%for those with two deliveries,and 24.6%for women with three or more *** causes immense suffering for pregnant *** To evaluate the relationship between the levator ani muscle’s hiatus(LH)area and POP in patients with gestational diabetes mellitus(GDM)using perineal *** The study cohort comprised 104 patients aged 29.8±3.7 years who sought medical care at our institution between January 2021 and June *** were singleton pregnancies consisting of 75 primiparas and 29 multiparas,with an average parity of 1.7±*** to the POP diagnostic criteria,the 104 subjects were divided into two groups with 52 members each:POP group(patients with GDM combined with POP)and non-POP group(patients with GDM without POP).Perineal ultrasound was used to measure differences in the anteroposterior diameter,transverse diameter,and LH *** operating characteristic curves were drawn to determine the optimal cutoff values for the LH anteroposterior diameter,transverse diameter,and area for diagnosing *** Statistically significant increase in the LH area,anteroposterior diameter,and lateral diameter were observed in the POP group compared with the non-POP group(P<0.05).Both groups exhibited markedly elevated incidence rates of macrosomia and stress urinary *** the POP group,the area under the curve(AUC)for the LH area was 0.906 with a 95%confidence interval(CI):*** optimal cutoff was 13.54cm²,demonstrating a sensitivity of 83.2%and a specificity of 64.4%.The AUC for the anteroposterior diameter reached 0.836 with a 95%CI:*** optimal cutoff was 5

关键词： Ultrasound Levator ani muscle hiatus Gestational diabetes mellitus Pelvic organ prolapse

A Stroke-Limitation AMD Control System with Variable Gain and Limited Area for High-Rise Buildings

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

工程与科学中的计算机建模(英文) 2024年第1期138卷 865-884页

作者： Zuo-hua Li qing-Gui Wu Jun Teng Chao-Jun Chen School of Civil and Environmental Engineering Harbin Institute of Technology(Shenzhen)Shenzhen518055China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong100872China

Collisions between a moving mass and an anti-collision device increase structural responses and threaten structural *** active mass damper(AMD)with stroke limitations is often used to avoid ***,a strokelimited AMD control system with a fixed limited area shortens the available AMD stroke and leads to significant control *** solve this problem,the design approach with variable gain and limited area(VGLA)is proposed in this ***,the boundary of variable-limited areas is calculated based on the real-time status of the moving *** variable gain(VG)expression at the variable limited area is deduced by considering the saturation of AMD ***,numerical simulations of a stroke-limited AMD control system with VGLA are conducted on a high-rise building *** numerical simulations show that the proposed approach has superior strokelimitation performance compared with a stroke-limited AMD control system with a fixed limited ***,the proposed approach is validated through experiments on a four-story steel frame.

关键词： High-rise buildings active control stroke limitations variable gain variable limited area

Configuring single-layer MXene nanosheet onto natural wood fiber via C-Ti-C covalent bonds for high-stability Li-S batteries

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 Energy Chemistry 2024年第8期95卷 701-711,I0016页

作者： yangyang Chen Yu Liao Ying Wu Lei Li Zhen Zhang Sha Luo Yiqiang Wu yan qing College of Materials Science and Technology Central South University of Forestry and TechnologyChangsha 410004HunanChina

Lithium-sulfur batteries(LSBs)are considered promising candidates for next-generation battery technologies owing to their outstanding theoretical energy density and ***,the low conductivity and polysulfide shuttling effect of S cathodes severely hamper the practical performance of ***,in situ-generated single layer MXene nanosheet/hierarchical porous carbonized wood fiber(MX/PCWF)composites are prepared via a nonhazardous eutectic activation strategy coupled with pyrolysis-induced gas *** unique architecture,wherein single layer MXene nanosheets are constructed on carbonized wood fiber walls,ensures rapid polysulfide conversion and continuous electron transfer for redox *** C-Ti-C bonds formed between MXene and PCWF can considerably expedite the conversion of polysulfides,effectively suppressing the shuttle *** impressive capacity of 1301.1 m A h g^(-1)at 0.5 C accompanied by remarkable stability is attained with the MX/PCWF host,as evidenced by the capacity maintenance of 722.6 m A h g^(-1)after 500 ***,the MX/PCWF/S cathode can still deliver a high capacity of 886.8 m A h g^(-1)at a high S loading of 5.6 mg cm^(-2).The construction of two-dimensional MXenes on natural wood fiber walls offers a competitive edge over S-based cathode materials and demonstrates a novel strategy for developing high-performance batteries.

关键词： Lithium-sulfur batteries S cathodes MXene nanosheets Wood fiber C-Ti-C bonds

Thickening progression mechanism of silica fume-oil well cement composite system at high temperatures

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第4期21卷 2793-2805页

作者： Hang Zhang Miao-Miao Hu Peng-Peng Li Guo-qing Liu qing-Lu Chang Jie Cao Ming Liu Wen-hua Xu Xiu-Jian Xia Jin-Tang Guo School of Chemical Engineering and Technology Tianjin University Zhejiang Institute of Tianjin University Haihe Laboratory of Sustainable Chemical Transformations CNPC Engineering Technology R&D Company Limited

This work studied the thickening progression mechanism of the silica fume-oil well cement composite system at high temperatures(110-180.C) in order to provide a theoretical guidance for the rational application of silica fume in the cementing engineering. Results showed that silica fume seldom affected the thickening progression of oil well cement slurry at 110-120.C, but when temperature reached above130.C, it would aggravate the bulging degree of thickening curves and significantly extend the thickening time, meanwhile causing the abnormal “temperature-based thickening time reversal” and“dosage-based thickening time reversal” phenomena in the range of 130-160.C and 170-180.C respectively. At 130-160.C, the thickening time of oil well cement slurry was mainly associated with the generation rate of calcium hydroxide(CH) crystal. The introduced silica fume would be attracted to the cement minerals' surface that were hydrating to produce CH and agglomerate together to form an“adsorptive barrier” to hinder further hydration of the inner cement minerals. This “adsorptive barrier”effect strengthened with the rising temperature which extended the thickening time and caused the occurrence of the “temperature-based thickening time reversal” phenomenon. At 170-180.C, the pozzolanic activity of silica fume significantly enhanced and considerable amount of C-S-H was generated, thus the “temperature-based thickening time reversal” vanished and the “dosage-based thickening time reversal” was presented.

关键词： Silica fume Oil well cement Thickening time reversal Pozzolanic reaction Adsorptive barrier CH and C−S−H

Ultrasound diagnosis of congenital Morgagni hernias: Ten years of experience at two Chinese centers

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2024年第3期12卷 495-502页

作者： Hui-qing Shi Wen-Juan Chen Qiang Yin Xue-hua Zhang Department of Ultrasound Fujian Children’s Hospital(Fujian Branch of Shanghai Children’s Medical Center)College of Clinical Medicine for Obstetrics&Gynecology and PediatricsFujian Medical UniversityFuzhou 350011Fujian ProvinceChina Department of Ultrasound Hunan Children’s HospitalUniversity of South ChinaChangsha 410007Hunan ProvinceChina Department of Pediatric Surgery Hunan Children’s HospitalUniversity of South ChinaChangsha 410007Hunan ProvinceChina

BACKGROUND Morgagni hernias are rare anomalies that are easily misdiagnosed or *** To summarize the ultrasound(US)imaging characteristics of Morgagni hernias through a comparison of imaging and surgical *** The records of children with Morgagni hernias who were hospitalized at two hospitals between January 2013 and November 2023 were retrospectively re-viewed in terms of clinical findings,US features,and operative *** Between 2013 and 2023,we observed nine(five male and four female)children with Morgagni *** abdominal scanning revealed a widening of the prehepatic space,with an abnormal channel extending from the xiphoid process to the right or left side of the thoracic *** channel had intestinal duct and intestinal gas *** contents were found in the transverse colon(n=6),the colon and small intestine(n=2),and the colon and stomach(n=1).Among the patients,seven had a right-sided lesion,two had a left-sided lesion,and all of them had hernial *** US imaging can accurately determine the location,extent,and content of Morgagni *** suspected Mor-gagni hernias,we recommend performing sonographic screening first.

关键词： Children Congenital diaphragmatic hernias Morgagni hernia Operation Ultrasound Gastrointestinal imaging

Ni/Co bimetallic organic frameworks nanospheres for highperformance electrochemical energy storage

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第6期17卷 5122-5130页

作者： Jianru Guan Minlu Liu Limin Zhu Jiamei Wang qing Han Xiaoxia yang Weibo hua Lingling Xie Xiaoyu Cao School of Chemistry and Chemical Engineering Key Laboratory of High Specific Energy Materials for Electrochemical Power Sources of Zhengzhou CityHenan University of TechnologyZhengzhou 450001China School of Chemical Engineering and Technology Xi’an Jiaotong UniversityXi’an 710049China School of Environmental Engineering Henan University of TechnologyZhengzhou 450001China

In addition to their many well-known advantages(e.g.,ultra-high porosity,good pore size distribution,easy functionalization,and structural tolerability),metal-organic frameworks(MOFs)are a new class of advanced functional ***,their backbones are highly susceptible to deformation after exposure to acidic or alkaline *** a result of lithium-ion batteries embedding or detaching directly from MOFs,they irreversibly *** a result,they fail to maintain their electrochemical *** factors have hindered the development of MOFs as direct electrode materials,making the design of MOF materials with controlled morphology and stable dimensions a new *** this study,we adopted a versatile and effective method to synthesize a novel MOF material(NiCo-BP(BP=BTC/phen and BTC=1,3,5-benzenetricarboxylic acid))using the rigid ligands 1,10-phenanthroline and homobenzotrizoic acid,and the emergence of the Ni-O/N and Co-O/N coordination layers was observed by extended X-ray absorption fine structure(EXAFS)tests,indicating that Ni and Co were coordinated with heterocyclic N-given atoms to form a stable p-πconjugated ***,the metal-ion is attached to the carboxylic acid ligand on the other side,making the metal-organic skeleton complete and *** nanosphere structure of NiCo-BP(~400 nm)allows for full exposure and utilisation of the active sites,especially the Ni,Co,and phenanthroline units,and exhibit impressively high specific capacity and cycling *** a high current density of 1.0 A·g^(−1),a high discharge specific capacity of 631.6 mAh·g^(−1)was obtained after 1000 *** co-participation of two organic ligands in the coordination is in accordance with the theory of soft and hard acids and bases,which contributes to the ability of the material to maintain a high capacity in cycling as well as its cyclic stability.

关键词： lithium-ion batteries metal organic frame electrochemical energy storage dual ligand hard-soft-acid-base

An experimental and theoretical study on photoluminescence of Ce^(3+)-doped ZnS quantum dots and their application in Aspergillus oryzae

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 Rare Earths 2024年第6期42卷 1020-1028,I0001页

作者： yan Lei Guangzhi Zhang Yitong Yao Gaiqin Zhu Zhong Chen Jiangrong Dan hua Liu Shuwang Duo School of Materials and Mechanical and Electrical EngineeringJiangxi Science and Technology Normal University Nanchang330013China

ZnS and ZnS:3.125%Ce^(3+)(ZSC)quantum dots(QDs)were synthesized by a low-temperature solid-phase *** crystal structure,photoluminescence(PL)properties of ZSC QDs,and their effects on the growth and kojic acid production of Aspergillus oryzae(***)were *** is found that both QDs have a cubic blend structure with the average particle size ranging of 2.75-6.14 ***^(3+)doping not only increases the band gap of ZnS QDs from 3.43 to 3.48 eV,but also increases the PL intensity by about 2.23 times,which is due to the fact that the electron carrier concentration is improved,and then the rate of radiative recombination is *** integral emission intensity,biomass,extracellular proteins yield,and kojic acid production of *** cultured with ZSC(ZnS)QDs are about 4.31(3.23),1.61(1.20),1.12(1.09),and 2.99(1.68)times higher than that of medium without QDs,respectively.

关键词： Zns Quantum dots Doping First-principles calculations Aspergllus oryzae Rare earths