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钼合金与低合金钢电子束焊接的力学性能研究

环境技术 2024年第6期42卷 195-199页

作者：王志洪熊星石林陶宇夏刚强中国电子科技集团公司第五十二研究所杭州311122

对TZM钼合金与30CrMnSi低合金高强钢进行电子束焊接试验,分析了焊接接头微观组织、界面结构以及接头力学性能。结果表明,束流偏向钢侧0.2 mm时,形成熔钎焊接头形式。在钼侧熔合线附近产生的界面区根据组织形貌与相组成划分为反应层Ⅰ与... 详细信息

对TZM钼合金与30CrMnSi低合金高强钢进行电子束焊接试验,分析了焊接接头微观组织、界面结构以及接头力学性能。结果表明,束流偏向钢侧0.2 mm时,形成熔钎焊接头形式。在钼侧熔合线附近产生的界面区根据组织形貌与相组成划分为反应层Ⅰ与反应层Ⅱ,结合能谱、线扫描分析和XRD分析表明反应层Ⅰ由连续分布的Fe2Mo相构成,会显著影响接头力学性能。拉伸结果表明,断裂沿反应层Ⅰ位置处扩展,呈现出脆性断裂特征,极限拉伸强度为209 MPa。显微硬度结果显示,沿水平方向接头不同特征区域硬度值差异较大,存在针状马氏体的钢侧热影响区显微硬度值最高,达到687 HV。

关键词：电子束焊接钼合金高强钢化合物层力学性能

畜禽粪便施用对红壤铝胁迫下油菜幼苗生长及光合荧光特性的影响

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福建农业学报 2024年第2期39卷 206-215页

作者：余居华王利民丁洪王煌平郑祥洲张玉树张银龙福建省农业科学院资源环境与土壤肥料研究所/福建省植物营养与肥料重点实验室福建福州350013 安徽大学资源与环境工程学院安徽合肥230601 南京林业大学南方现代林业协同创新中心江苏南京210037

【目的】红壤铝毒是限制作物生长的主要因素,畜禽粪便等有机物料作为改善土壤酸度和推动国家化肥零增长行动计划的重要途径之一,其对铝毒胁迫下作物生长及光合荧光特性的影响及其机理研究具有重要意义。【方法】利用盆栽试验,探究不施... 详细信息

【目的】红壤铝毒是限制作物生长的主要因素,畜禽粪便等有机物料作为改善土壤酸度和推动国家化肥零增长行动计划的重要途径之一,其对铝毒胁迫下作物生长及光合荧光特性的影响及其机理研究具有重要意义。【方法】利用盆栽试验,探究不施畜禽粪便(CK)、施用猪粪10 g·kg^(-1)(P10)、猪粪30 g·kg^(-1)(P30)、猪粪50g·kg^(-1)(P50)、鸡粪10 g·kg^(-1)(C10)、鸡粪30 g·kg^(-1)(C30)、鸡粪50 g·kg^(-1)(C50)、鸡粪猪粪各15 g·kg^(-1)(PC15)等8个处理对酸性土壤铝毒胁迫下油菜(Brassica napus L.)生物量、光合作用参数和叶绿素荧光特性的影响。【结果】在土壤铝毒胁迫下,不同畜禽粪便处理均促进了油菜幼苗地上部生物量、光合色素含量、光合作用和叶绿素荧光特性,在第80天各处理均显著大于对照组(P<0.05),表明畜禽粪便有效缓解红壤铝胁迫对油菜幼苗生长的毒害作用。施用等量鸡粪处理比猪粪更有利于促进油菜幼苗地上部生物量、光合色素含量,但对光合作用参数、Fv/Fm值和qP的促进作用较弱,而且鸡粪、猪粪混施处理光合色素含量、光合参数Tr、Gs、Ci、qN均大于单施处理(P<0.05),说明高pH值的鸡粪更利于促进油菜生长,而高养分含量的猪粪更利于促进油菜光合荧光特性。【结论】猪粪施用量50 g·kg^(-1)对油菜生长及光合荧光特性的铝毒胁迫缓解作用最佳,而鸡粪最佳施用量为30g·kg^(-1)。就油菜幼苗生长和光合荧光特性而言,畜禽粪便种类筛选、最佳用量确定并结合土壤酸度调控对缓解红壤铝毒至关重要。

关键词：红壤畜禽粪便铝毒生长光合荧光油菜

Identifying the active sites in C-N codoped TiO_(2) electrode for electrocatalytic water oxidation to produce H_(2)O_(2)

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Journal of Central South University 2022年第9期29卷 3016-3029页

作者： XUE Sheng-guo TANG Lu TANG Tian ZHANG Feng Lyu Hua-gang LIU hong-yu JIANG Jun HUANG Yan-hong School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution Central South UniversityChangsha 410083China Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering School of Chemistry and Chemical EngineeringHefei University of TechnologyHefei 230009China Guangxi Research Institute of Environmental Protection Nanning 530000China

Unveiling the active site of an electrocatalyst is fundamental for the development of efficient electrode *** the two-electron water oxidation to produce H_(2)O_(2),competitive reactions,including four-and one-electron water oxidation and surface reconstruction derived from the high-oxidative environment co-existed,leading to great challenges to identify the real active sites on the *** this work,Ti/TiO_(2)-based electrodes calcined under air,nitrogen,or urea atmospheres were selected as electrocatalysts for two-electron water *** analyses were applied to evaluate the catalytic activity and *** morphological and current change on the electrode surface were determined by scanning electrochemical microscopy,while the chemical and valence evolutions with depth distributions were tested by XPS combined with cluster argon ion *** results demonstrated that Ti/TiO_(2) nanotube arrays served as the support,while the functional groups of carbonyl groups and pyrrolic nitrogen derived from the co-pyrolysis with urea were the active sites for the H_(2)O_(2) *** finding provided a new horizon to design efficient catalysts for H_(2)O_(2) production.

关键词： hydrogen peroxide in-situ characterization titanium dioxide electrode carbonyl pyrrolic nitrogen

IMB模型健康教育对高尿酸血症患者依从性和痛风发作控制的影响

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上海医药 2024年第12期45卷 59-62页

作者：余燕飞陈丽云陈雪华周红上海市奉贤区金海社区卫生服务中心病房上海201403 上海市奉贤区四团镇平安社区卫生服务中心医院感染科上海201413

目的:探究基于信息-动机-行为技巧(IMB)模型健康教育对高尿酸血症患者依从性和血尿酸的影响。方法:使用随机数字表法将2021年1-12月在金海社区卫生服务中心体检的70例高尿酸血症患者分为两组,每组35人,对照组进行常规随访管理,试验组以... 详细信息

目的:探究基于信息-动机-行为技巧(IMB)模型健康教育对高尿酸血症患者依从性和血尿酸的影响。方法:使用随机数字表法将2021年1-12月在金海社区卫生服务中心体检的70例高尿酸血症患者分为两组,每组35人,对照组进行常规随访管理,试验组以IMB模型健康教育进行干预,对比两种方式对高尿酸血症患者的血尿酸、血糖、肝肾功能等生化检测的影响,以及对患者的依从性及痛风发作控制情况的影响。结果:干预后试验组患者在知识得分及健康行为依从性方面均优于对照组,差异有统计学意义(P<0.05);干预后试验组血尿酸值、痛风发作次数均小于对照组,差异有统计学意义(P<0.05)。结论:IMB模型健康教育有效提高了高尿酸血症患者的知识知晓度,并且进一步推动患者对健康行为的依从性,从而降低血尿酸,改善痛风发作次数及不良代谢状况。

关键词：高尿酸血症痛风 IMB模型健康教育

Thoraco-abdominal Aorta Revascularization through a Retroperitoneal Approach

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Chinese Medical Sciences Journal 2010年第4期25卷 233-236页

作者： yue-hong Zheng Kun yu Jie-feng Zhang Nim Choi hong-ru Deng Furtado Rui Department of Vascular Surgery Peking Union Medical College Hospital ChineseAcademy of Medical Sciences ＆ Peking Union Medical College Beijing 100730 China Department of Extracorporeal Circulation Fuwai Hospital Beijing 100037 China Department of Vascular Surgery Weifang People＇s Hospital Shandong 261041 China Department of General Surgery Cir Gen/Vas Central Hospital Centre S. Januario Macao China

Objective To investigate the application of the retroperitoneal approach in aortic surgery. Methods We collected and analyzed data of 7 patients in Macao who presented with aortic diseases from 2007 to 2008 and were treated with aorta repair through retroperitoneal approach. Demographic features as well as intraoperative and postoperative data were analyzed. One case of thoracoabdominal aneurysm and 4 cases of abdominal aneurysm received artificial graft, among which hybrid iliac artery reconstruction with Zenith stent covering the ostium of the left subclavian artery was performed in 2 cases of infrarenal abdominal aneurysm. Aortic-iliac artery bypass was performed in 2 cases of aortoiliac occlusion. Results No operative or early postoperative death was observed. No perioperative intestinal adhesion or ureteral obstruction was found. One case reported delayed paraplegia and graft infection as postoperative complications. The complications were partially removed 3 months later after rehabilitation. Conclusion Retroperitoneal approach is a safe and feasible technique, which associated with a low incidence of postoperative pulmonary complications.

关键词： aorta retroperitoneal approach revascularization

Synthesis of Nanoscale Shell-core Titania Coated Silica Particles in the Presence of Polyether Polyamine and the Phase Transition

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Chemical Research in Chinese Universities 2002年第1期18卷 70-74页

作者： HUA Feng-jun SUN Jun hong Ke GAO Lian YANG yu-liang Key Laboratory of Molecular Engineering of Polymer Fudan UniversityShanghai 200433P.R.China State Key Laboratory of High Performance Ceramics and SuperfineMicrostructure Shanghai Institute of CeramicsShanghai 200433.P.R.China

The nanoscale titania coated silica was prepared via a two-step precipitating approach, where the nanoscale silica nuclei were first prepared by passing an aqueous solution of sodium silicate through an ion-exchange resin bed, then coated with the precipitation from hydrolyzed butyl titanate in an ethanol-hexane mixture at a low pH value in the presence of poly(ethylene oxide) polyamine salt(PPA) at a high temperature of 90 ℃. In the second-step precipitating process, the spontaneously precipitated titania shell on the silica nuclei was stabilized in the suspension solution with the help of the adsorption of PPA on the particles. A possible precipitating mechanism was suggested. Furthermore, the amorphous titania shell could undergo crystallization from the amorphous to the anatase structure at a high temperature of 650 ℃, and a further phase transition from the anatase to the rutile structure in the different sintering processes at a rising temperature of 750 ℃.

关键词： Nanoscale particle Silica sol Titania coated silica

TRANSVERSE MIXING IN A TRAPEZOIDAL COMPOUND OPEN CHANNEL

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Journal of Hydrodynamics 2008年第5期20卷 645-649页

作者： ZENG yu-hong HUAI Wen-xin GUYMER I. State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan430072 China School of Engineering University of Warwick Coventry CV4 7AE UK

Transverse mixing characteristics of solute in the open channel flow can provide useful information for river environmental management. The lateral mixing coefficient is a crucial parameter for reproducing the transverse mixing either by numerical simulation or by analytical prediction. Since the solute mixing can be greatly affected by the lateral variations in water depth, mixing coefficient should be determined in each sub-section （i.e., the main channel, side slope and flood plain） separately. In this article, the transverse mixing in a symmetric trapezoidal compound channel was studied based on laboratory measurement of longitudinal and transverse velocity components and lateral distribution of solute concentration. The lateral mixing coefficient was estimated by adopting different Schmidt numbers in different sub-sections divided according to the developing trend of the eddy viscosity, and finally a piecewise linear profile of mixing coefficient was adopted to analytically predict the transverse solute concentration. The comparison between the analytically predicted data and the measuring solute concentration proved that this is an effective way to estimate the lateral mixing in the open channel flow with lateral variations in water depth,

关键词： transverse mixing trapezoidal compound channel mixing coefficient

A Single Point Mutation in GmHMA3 Affects Cadimum （Cd） Translocation and Accumulation in Soybean Seeds

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Molecular Plant 2012年第5期5卷 1154-1156页

作者： Yi Wang Kang-Fu yu Vaino Poysa Chun Shi Yong-hong Zhou Greenhouse and Processing Crops Research Centre Agriculture andAgri-Food Canada 2585 County Road 20HarrowOntarioN0R 1G0 Canada Triticeae Research Institute Sichuan Agricultural University Wenjiang 611130Sichuan China

Dear Editor, Soybean can absorb and accumulate Cd from soils in their seed. Consumption, either directly or indirectly, of seed with high levels of Cd could be a human health concern, in 2001, the Codex Committee on Food Additives and Contaminants of the Codex Alimentarius Commission established by the Food and Agriculture Organization and the World Health Organization proposed an upper limit of 0.2 mg kg-1 Cd con- centration in soybean grain （Codex Alimentrius Commission, 2001）. There are cultivar differences in seed Cd concentration in soybean and some cultivars accumulate high Cd concen- trations in seed when grown on Cd-contaminated soils （Arao et al., 2003）. These cultivars can exceed the proposed Codex upper limit. Cdal, a major gene controlling seed Cd accumu- lation, has been mapped on linkage group K by Jegadeesan et al. （2010）. The molecular mechanism of the Cdal gene underlyincl Cd accumulation in soybean seed is unknown.

关键词： Translocation Accumulation Soybean

Interpenetrating LiB/Li3BN2 phases enabling stable composite lithium metal anode

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Science Bulletin 2024年第18期69卷 2842-2852页

作者： Qing, Piao Huang, Shaozhen Naren, Tuoya Li, Quan Huang, Haifeng Long, Kecheng Liu, Zhijian Mei, Lin Sun, Fu Wei, Weifeng Zhang, yu Ma, Jianmin Wu, Zhibin Chen, Libao State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China National Energy Metal Resources and New Materials Key Laboratory Central South University Changsha 410083 China Department of Physics The Chinese University of Hong Kong Hong Kong 999077 Hong Kong Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of Sciences Qingdao 266101 China Key Laboratory of Bio-inspired Smart Interfacial Science and Technology of Ministry of Education School of Chemistry Beihang University Beijing 100191 China School of Chemistry Tiangong University Tianjin 300387 China

Host-less lithium metal anode generally suffers from large volume changes and serious dendrite growth during cycling, which poses challenges for its practical application. Interpenetrating phase composites with continuous architectures offer a solution to enhance mechanical properties of materials. Herein, a robust composite Li anode (LBN) material is fabricated through the metallurgical reaction between Li and hexagonal boron nitride (h-BN) with the formation of interpenetrating LiB/Li3BN2 phases. As LiB fibers are anchored by Li3BN2 granules, the collapse and slippage of LiB fibers are suppressed whilst the mechanical strength and structural stability of LBN are reinforced. By rolling, ultrathin (15 μm), freestanding, and electrochemically stable LBN foil can be obtained. The LBN anode exhibits a high average Coulombic efficiency of 99.69% (1 mA cm−2, 3 mAh cm−2) and a long lifespan of 2500 h (1 mA cm−2, 1 mAh cm−2). Notably, the LiCoO2 (with double-sided load 40 mg cm−2)|LBN pouch cell can operate over 450 cycles with a capacity retention of 90.1%. The exceptional cycling stability of LBN can be ascribed to the interpenetrating reinforcement architectures and synergistic electronic/ionic conductivity of the LiB/Li3BN2 dual-lithiophilic-phases. This work provides a new methodology for thin Li strip processing and reinforced-architecture design, with implications beyond battery applications. © 2024 Science China Press

关键词： Lithium compounds