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Chinese Chemical Letters 1998年第9期9卷 869-872页

作者： Zhi Qiang FAN Qi WANG Jian hua WENG Lin xian feng (Institute of Polymer Science and Materials, Zhejiang University, hangzhou 310027) Inst. of Poly. Science and Materials Zhejiang University Hangzhou 310027 China

Aluminoxanes containing both ethyl and iso-butyl groups were synthesized by thehydrolysis of Al(C2h3)3 (TEA)/Al(i-C4h9)3 (TIBA) mixtures. The aluminoxane made from theTEA/TIBA mixture of molar ratio 7:3 showed cocatalyst activity of about five times as those ofethylaluminoxane or isobutylaluminoxane for ethylene polymerization catalyzed by Cp2ZrCl2. Thealuminoxane was characterized and the possible reasons for its high activity were discussed.

关键词： aluminoxane cocatalyst metallocene ethylene polymerization

LARGE-SCALE FARMING BENEFITS SOIL ACIDIFICATION ALLEVIATION ThROUGh IMPROVED FIELD MANAGEMENT IN BANANA PLANTATIONS

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Frontiers of Agricultural Science and Engineering 2023年第1期10卷 48-60页

作者： Donghao xU Jiangzhou ZhANG Yajuan LI Shiyang LI Siyang REN Yuan feng Qichao ZhU Fusuo ZhANG College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193China National Academy of Agriculture Green Development China Agricultural UniversityBeijing 100193China College of Resources and Environment/International Magnesium Institute Fujian Agriculture and Forestry UniversityFuzhou 350002China

Large-scale farming by agricultural land transfers has been increasingly promoted in recent years,but the possible impacts on crop production,especially cash crops,and soil acidification remain *** study obtained data for 110 banana plantations in Long’an County,China,and categorized them into small(ha),medium(0.67−6.7 ha),and large(>6.7 ha)to determine banana cultivation,nutrient management,and soil acidification rates on farms of the three *** yield per unit area significantly increased with increased farm size,and large farms had the highest average yield(48.9 t·ha^(−1))with the least *** a significant increase in organic fertilizer and base cation inputs,nitrogen(N)surplus did not differ significantly with increasing farm *** large farms,actual soil acidification rate was significantly lower by 19.1 to 24.0 keq·ha^(−1)·yr^(−1);however,potential soil acidification rate increased with increased overuse of ***,larger banana plantations used fewer mineral N fertilizers reducing the rate of soil acidification and increasing the h+buffering provided by organic *** is concluded that larger farms deliver the dual benefits of higher,less variable banana yield and mitigation of soil acidification by substituting organic N for mineral N fertilizers,supporting sustainable soil management and food production.

关键词： plantations land transfer large-scale farming nutrient management soil acidification

功能性微创理念在先天性巨结肠患儿围手术期应用临床研究

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临床小儿外科杂志 2024年第1期23卷 22-28页

作者：阿迪拉·阿不都萨拉木王文静朱天琦熊晓峰贺颖刘率斌杨继鑫冯杰雄华中科技大学同济医学院附属同济医院小儿外科，武汉430030

目的探讨功能性微创理念在先天性巨结肠患儿围手术期应用的可行性及临床效果。方法回顾性分析2019年3月至2023年3月于华中科技大学同济医学院附属同济医院采取心形吻合术治疗的先天性巨结肠患儿临床资料。共有82例先天性巨结肠患儿纳入... 详细信息

目的探讨功能性微创理念在先天性巨结肠患儿围手术期应用的可行性及临床效果。方法回顾性分析2019年3月至2023年3月于华中科技大学同济医学院附属同济医院采取心形吻合术治疗的先天性巨结肠患儿临床资料。共有82例先天性巨结肠患儿纳入研究,其中功能性微创(functional minimally invasive,FMI)组45例,非功能性微创(non-functional minimally invasive,non-FMI)组37例。FMI组中,男34例、女11例,手术年龄(1.31±0.96)岁;non-FMI组中,男28例、女9例,手术年龄(1.16±0.63)岁。比较两组患儿术后首次经口喂养时间、首次排便时间、住院时间、肛管拔出时间、疼痛评分、并发症等方面的差异。两独立样本t检验用于服从正态分布连续变量的差异性检验,Mann-Whitney U检验用于非正态分布连续变量的差异性检验;分类变量采用卡方精确检验。结果与non-FMI组相比,FMI组术后拔出肛管的时间[(9.23±1.47)d比(11.50±1.91)d,P=0.001]和首次开始肠内营养的时间明显缩短[(36.92±19.01)h比(56.76±17.22)h,P=0.005],术后6个月总体并发症发生率明显降低(P=0.038),术后苏醒时及术后24 h疼痛评分均明显降低(Ph比(28.91±12.61)h,P=0.937]、住院时间[(11.56±4.18)d比(13.19±3.67)d,P=0.473]及住院费用[(43087.23±4729.14)元比(62036.34±3129.77)元,P=0.312]比较,差异均无统计学意义(P>0.05)。结论功能性微创理念应用于先天性巨结肠的手术治疗是有效和安全的,可促进患儿术后康复,减轻术后疼痛,减少由于留置引流产生的不适,减少术后并发症的发生。

关键词：先天性巨结肠功能性微创腹腔镜外科手术儿童

Synergistic Effect of Sandwich Polyoxometalate and Copper-Imidazole Complexe for Enhancing Peroxidase-like Activity

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Synergistic Effect of Sandwich Polyoxometalate and Copper-Im...

Mn3O4/carbon nanotube nanocomposites recycled from waste alkaline Zn–MnO2 batteries as high-performance energy materials

中国化学会第九届全国无机化学学术会议

作者： Dong-feng Chai Yun-feng Qiu hong Liu Department of Chemistry College of Pharmacy Jiamusi University State Key Laboratory of Robotics and System (hIT) Academy of Fundamental and Interdisciplinary SciencesHarbin Institute of Technology

h2O2 detection has attracted much attention in recent years due to that its production may affect many biochemistry reactions in the body that may be dangerous for human health.[1-3] herein, an inorganic-organic hybrid based on copper（II）-imidazole complexe modified sandwich-type tungstobismuthate, Na4h2[Cu4（h4im）12（h3im）2][Cu3（h2O）6（Bi W9O33）2]·40h2O（h4im = imidazole, h3 im = deprotonated imidazole）（1） has been synthesized and structurally characterized by single crystal x-ray diffraction. Compound 1 was demonstrated to possess high peroxidase-like activity when using 3, 3’, 5, 5’-tetramethylbenzidine（TMB） as a peroxidase substrate in the presence of h2O2. The synergistic effects of sandwich-type polyoxometalate and copper（II）-imidazole complexe is responsible for the enhancement of peroxidase-like activity than polyoxometalate and copper（II）-imidazole complexe. Considering the dependence of TMB coloration on h2O2 concentrations, 1 can be used as an effective biosensor to detect h2O2 through facile colorimetric method in a linear range from 1 μM to 50 μM with a low detection limit of 0.12 μM. Compound 1opens a new approach to the h2O2 sensor by inorganic-organic hybrid compounds.

关键词： Polyoxometalate peroxidase-like enzyme copper-imidazole

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Rare Metals 2017年第5期36卷 442-448页

作者： Li-hua Zhang Si-Si Wu Yi Wan Yi-feng huo Yao-Cong Luo Ming-Yang Yang Min-Chan Li Zhou-Guang Lu Laboratory of Green and Renewable Energy Materials Department of Materials Science and EngineeringSouth University of Science and Technology of ChinaShenzhenChina

Alkaline zinc manganese dioxide（Zn–MnO2）batteries are widely used in everyday life. Recycling of waste alkaline Zn–MnO2 batteries has always been a hot environmental concern. In this study, a simple and costeffective process for synthesizing Mn3O4/carbon nanotube（CNT） nanocomposites from recycled alkaline Zn–MnO2 batteries is presented. Manganese oxide was recovered from spent Zn–MnO2 battery cathodes. The Mn3O4/CNT nanocomposites were produced by ball milling the recovered manganese oxide in a commercial multi-wall carbon nanotubes（MWCNTs） solution. Scanning electron microscopy（SEM） analysis demonstrates that the nanocomposite has a unique three-dimensional（3D） bird nest structure. Mn3O4 nanoparticles are homogeneously distributed on MWCNT framework. Mn3O4/CNT nanocomposites were evaluated as an anode material for lithium-ion batteries, exhibiting a highly reversible specific capacitance of -580 mA h·g^-1 after 100 cycles. Moreover, Mn3O4/CNT nanocomposite also shows a fairly positive onset potential of -0.15 V and quite high oxygen reducibility when considered as an electrocatalyst for oxygen reduction reaction.

关键词： Waste Zn–MnO2 batteries Recycling Nanocomposites Anode materials Oxygen reduction reaction

Raman scattering investigation of twisted WS_(2)/MoS_(2) heterostructures: interlayer mechanical coupling versus charge transfer

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Nano Research 2021年第7期14卷 2215-2223页

作者： Lishu Wu Chunxiao Cong Jingzhi Shang Weihuang Yang Yu Chen Jiadong Zhou Wei Ai Yanlong Wang Shun feng hongbo Zhang Zheng Liu Ting Yu Division of Physics and Applied Physics School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore 637371Singapore School of Information Science and Technology Fudan UniversityShanghai 200433China Shaanxi Institute of Flexible Electronics Northwestern Polytechnical UniversityXi’an 710129China Engineering Research Center of Smart Microsensors and Microsystems Ministry of EducationCollege of Electronics and InformationHangzhou Dianzi UniversityHangzhou 310018China School of Materials Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore Key Laboratory of Chemical Lasers Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Twisted van der Waals homo-and hetero-structures have aroused great attentions due to their unique physical properties,providing a new platform to explore the novel two-dimensional(2D)condensed matter *** robust dependence of phonon vibrations and electronic band structures on the twist angle has been intensively observed in transition metal dichalcogenide(TMD)***,the effects of twist angle on the lattice vibrational properties in the TMD heterostructures have not caused enough ***,we report the distinct evolutions of Raman scattering and the underlying interlayer interactions in the twisted WS_(2)/MoS_(2) *** shifts and linewidths of E_(2g)(Γ)and A_(1g)(Γ)phonon modes are found to be twist angle *** particular,analogous to that of the twisted TMD homostructures,the frequency separations between E_(2g)(Γ)and A_(1g)(Γ)modes of MoS_(2) and WS_(2) in the twisted heterostructures varying with twist angle correlate with the interlayer mechanical coupling,essentially originating from the spacing-related repulsion between sulfur ***,the opposite shift behaviors and broadening of A_(1g)(Γ)modes caused by charge transfer are also observed in the twisted *** calculated interlayer distances and band alignment of twisted WS_(2)/MoS_(2) through density functional theory further evidence our interpretations on the roles of the interlayer mechanical coupling and charge transfer in variations of Raman *** understanding and controlling of interlayer interaction through the stacking orientation are significant for future optoelectronic device design based on the newly emerged 2D heterostructures.

关键词： van der Waals heterostructures interlayer coupling Raman scattering twist angle charge transfer

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The Nature of Light

工程科学（英文版） 2007年第1期5卷 65-77页

作者： Fan Liangzao feng Jinsong Chinese Academy of Sciences Beijing 100086 Chongqing xinda Group Chongqing 408200

关于红外线的、可见的光的光子 h 的精力单位的宽分发，紫外， Gamma 光线和 x 光线建议光子不是基本粒子，并且每光子由 N 组成微光子[1 ] egual 质量。我们发现光子和 N() 的波长的产品是不变的 =N()[2 ] 。然后， Plack 的常数和波... 详细信息

关于红外线的、可见的光的光子 h 的精力单位的宽分发，紫外， Gamma 光线和 x 光线建议光子不是基本粒子，并且每光子由 N 组成微光子[1 ] egual 质量。我们发现光子和 N() 的波长的产品是不变的 =N()[2 ] 。然后， Plack 的常数和波浪粒子两重性的新解释基于微光子的理论被形成。光子的波长只是距离间隔在之间二邻近微光子并且频率代表数字微光子每联合起来射出时间。由 N 数字的空间结构指导了微光子，现在的论文另外推断在所有惯性的框架的 c = defincted 是 invarient，是总是真的。现在，原则光，由爱因斯坦不变的速度不再是一个假设，而是一个事实。然而，波长和频率的调查结果有时在不同惯性的框架不同，它将可能质问相关性的原则。另外，孔 difraction，折射和 reflectron 的公式进行了。

关键词： photons wave-particle duality atomic spectrum special relativity

Comparative Study on Spillover Effect of Technology Import in BRICs

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一种新型板式臭氧消毒机对空气及物体表面消毒效果研究

2011公共管理国际会议（第七届）

作者： LIU Lian-feng JIANG Nan LIU feng-chao School of business management Dalian University of Technology

This paper improves C-h model, utilizes LP method about knowledge spillover of import trade and makes comparative analysis about technology spillover effect of FDI and import trade of BRICs. The results show that the spillover effects of technology import in BRICs are different, while China and India can handle the relationship between domestic and foreign resources well to promote technology progress of the host country.

关键词： Technology import Spillover effect Total factor productivity C-h model

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中国消毒学杂志 2024年第3期41卷 179-182页

作者：曹越帖金凤晁思琪吕军苹袁乐王鲁哈尔滨工业大学环境学院黑龙江哈尔滨150090 中国人民解放军疾病预防控制中心中央民族大学药学院

目的观察一种小间距板式催化臭氧消毒机对密闭空间内空气、物体表面消毒效果以及对金属腐蚀性。方法采用载体定量杀菌试验和现场消毒试验方法,对某板式催化臭氧消毒机的消毒效果及其金属腐蚀性进行观察。结果该臭氧消毒机以10 mg/m^(3)... 详细信息

目的观察一种小间距板式催化臭氧消毒机对密闭空间内空气、物体表面消毒效果以及对金属腐蚀性。方法采用载体定量杀菌试验和现场消毒试验方法,对某板式催化臭氧消毒机的消毒效果及其金属腐蚀性进行观察。结果该臭氧消毒机以10 mg/m^(3)臭氧量对空气中白色葡萄球菌作用30 min,平均杀灭率为99.99%;对布片载体上大肠埃希菌作用40 min,对金黄色葡萄球菌作用120 min,杀灭对数值均>3.00。该臭氧消毒机以30 mg/m^(3)臭氧量对纸片载体上枯草杆菌黑色变种芽孢作用3 h,杀灭对数值>3.00。该臭氧消毒机以20 mg/m^(3)臭氧量,循环处理20次,累计60 h,对不锈钢片、碳钢片、铜片和铝片基本无腐蚀。结论该臭氧消毒机在常温下可用于空气和物体表面消毒,对纸片染菌载体可达到高效消毒效果,并且对金属基本无腐蚀性。

关键词：板式臭氧消毒机空气消毒物体表面消毒腐蚀性

R_2Fe_(14)B型永磁材料中第二磁晶各向异性常数对反磁化过程的影响

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物理学报 2005年第8期54卷 3856-3861页

作者：陈宪锋江苏工业学院信息科学系常州213016

针对低温下各向同性Pr2Fe14B永磁材料的最小形核场问题,用数值计算法和近似解析解研究了第二磁晶各向异性常数K2对最小形核场的影响.研究发现,尽管对于Nd2Fe14B永磁材料一级近似的解析解与数值计算结果很接近,但是对于低温下各向同性Pr2... 详细信息

针对低温下各向同性Pr2Fe14B永磁材料的最小形核场问题,用数值计算法和近似解析解研究了第二磁晶各向异性常数K2对最小形核场的影响.研究发现,尽管对于Nd2Fe14B永磁材料一级近似的解析解与数值计算结果很接近,但是对于低温下各向同性Pr2Fe14B永磁材料则至少要用二级近似下的解析解才能与数值计算结果相接近.用有关最小形核场的计算结果很好地解释了低温时各向同性Pr2Fe14B永磁材料的矫顽力与最小形核场的关系.

关键词：磁晶各向异性常数永磁材料磁化过程 Pr2Fe14B 4B型 Nd2Fe14B 各向同性计算结果近似解析解数值计算法二级近似形核最小场问题低温矫顽力接近