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Optimization design and experiment of the variable differential gear train planting mechanism

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 85-93页

作者： xiong zhao Ziwei Liu Yuanwu Jia Xingxiao Ma Pengfei zhang Jianneng Chen School of Mechanical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Xi’an International University Engineering College Xi’an 710077China Hangzhou Vocational&Technical College Hangzhou 310018China

In order to improve the adaptability of the planting mechanism for different plant spacings,a variable differential gear train planting mechanism based on precise pose and trajectory control was proposed by combining the open chain 2R rod group and the variable differential gear *** to the pose requirements of receiving seedling point,transporting seedling point and planting point,three precise pose points of constrained planting trajectory were *** the three-position motion generation structural synthesis method,combined with computer-aided optimization design software,a set of mechanism parameters that meet the planting requirements were *** on the optimized mechanism parameters,by only changing the coordinates of two trajectory shape control points,three planting trajectories with key point position information adapted to 300 mm,400 mm and 500 mm plant spacing were obtained by interpolation,and three pairs of total transmission ratio of three groups of variable differential gear trains were *** distributing the total transmission ratio of the mechanism,the fixed axis gear train and the differential gear train are *** fixed axis gear train included a pair of non-circular gear pairs and a pair of positive gear pairs,which were convenient for disassembly and *** former drives the sun gear at variable speed,and the latter drives the planet carrier at uniform *** on this structure,the transmission ratio of the positive gear pair is-1,and the transmission ratio of the differential gear train is *** sub-transmission ratio of the single-stage non-circular gear pair was calculated and the pitch curves of three pairs of noncircular gears were *** pairs of non-circular gear pairs with different transmission ratios were replaced in turn and three sets of planting mechanisms were modeled in three *** virtual prototype motion simulation was completed by ADAMS software,and the p

关键词： plant spacing planting mechanism variable differential gear train precise pose trajectory control parameter optimization

Improved Mechanical Properties of Poly(butylene succinate) Membrane by Co-electrospinning with Gelatin

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Chinese Journal of Polymer Science 2018年第9期36卷 1063-1069页

作者： Lu Chen Hui-Hui Cheng Jiang xiong Ya-Ting Zhu Hong-Peng zhang Xi xiong Yu-Man Liu Jian Yu zhao-Xia Guo Key Laboratory of Advanced Materials (Ministry of Education) Department of Chemical Engineering Tsinghua University Department of Vascular and Endovascular Surgery Chinese PLA General Hospital

Gelatin, a natural proteinous polymer, was used to co-electrospin with poly（butylene succinate）（PBS） in order to improve the mechanical properties of PBS membrane and facilitate its applications in biomedical field. The PBS/gelatin blend membranes have narrower distribution of fiber diameter and smoother surface than neat PBS membrane. The contact angles, water absorption rates and water uptakes of the PBS/gelatin blend membranes were measured, showing increased hydrophilicity. The interaction between PBS and gelatin was investigated by attenuated total reflectance Fourier transform infrared spectroscopy （ATR-FTIR） and differential scanning calorimetry （DSC）. The mechanical properties of PBS/gelatin blend membranes in both dry and wet states were evaluated by uniaxial tensile tests. In the dry state, the PBS/gelatin blend membrane containing 10% gelatin has a 3-times increase in tensile strength without any adverse effect on ductility because of the existence of interaction between the two blend components, little change in crystallinity of PBS, and possible interaction between any adjacent fibers; the tensile strength and elongation at break are even better in the wet state attributed to some gelatin on fiber surfaces, which act as a binder in the presence of water. The potential applications of PBS/gelatin blend membranes were demonstrated by successful immobilization of thrombin, a clinically-used hemostatic drug. The thrombin-loaded membrane could be used for rapid hemostasis.

关键词： PBS Gelatin Electrospinning Mechanical properties Blending

Effect of red clover isoflavones on hormone,immune,inflammatory,and plasma biochemistry in lactating dairy cows

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Animal Nutrition 2024年第1期16卷 306-312页

作者： Shiqi zhang Xiaoyin zhang Zhanbo xiong Kexin Li Yuan Gao Ying Bu Nan Zheng Shengguo zhao Jiaqi Wang State Key Laboratory of Animal Nutrition Institute of Animal SciencesChinese Academy of Agricultural SciencesBeijing 100193China

This study was to conducted to investigate the effect of red clover isoflavones on the health indicated by immune status and blood biochemistry in dairy ***-eight healthy Holstein lactating cows were randomly divided into four treatments(n=17 per treatment)from 5 blocks according to milk yield using a randomized complete block *** initial differences in parity(2.13±1.21),days in milk(165±21 d),and milk yield(33.93±3.81 kg/d)between *** were fed the basal diet supplemented with 0,2,4,or 8 g/kg red clover extract(RCE)in diet(dry matter based).Feeding,refusal feed weights,and milk yield were recorded three consecutive days in weeks 0,4,8,and *** was collected from the tail vein of the cows on the last day of weeks 4,8 and 12,1 h after the morning feeding,and analyzed for hormones,immunoglobulins,inflammatory markers,and markers of liver and kidney *** dry matter intake was significantly decreased by 3.7%in the 8 g/kg group(P0.05).These results recommend the supplementation of RCE at a level from 2 to4 g/kg DM.

关键词： Dairy cow Red clover isoflavone Immunity Anti-inflammatory

Microstructure and properties of MOCVD-derived Gd_xY_(1-x)Ba_2Cu_3O_(7-δ) films with composition fluctuations

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Rare Metals 2018年第8期37卷 675-681页

作者： Yu-Xi zhang Fei zhang Rui-Peng zhao Yan Xue Hui Wang Qiu-Liang Wang Jie xiong Bo-Wan Tao State Key Laboratory of Electronic Thin Film and Integrated Devices University of Electronic Science and Technology of China Applied Research Laboratory of Superconduction and New Material Institute of Electrical EngineeringChinese Academy of Sciences

The effects of Gd content on crystalline orientation, microstructure and superconductivity of GdxYl-x-BazCu3O7-δ（GdYBCO） films were systematically investigated. By varying the Gd content in the liquid precursor without changing the total amount of rare earth elements, series of GdYBCO films with x values of 0, 0.1, 0.3, 0.5, 0.7, 0.9 and 1.0 were fabricated by metal organic chemical vapor deposition （MOCVD）. X-ray diffraction （XRD） and scanning electron microscope （SEM） analysis revealed that Gd introducing could restrain the formation of CuYOa phase, but induce a-axis growth of GdYBCO film. The increase of x from 0 to 0.5 leads to enhancing critical current density at self-field and 77 K （Jcs0 from 1.8 to 2.8 ***^-2, which benefits from the decrease in CuYO2 impurities and improvement of in-plane texture from 5.0° to 4.3°. However, raising x from 0.5 to 1.0 gives rise to abundant a-axis growth of film and degradation of in-plane texture from 4.3° to 5.4°, consequently resulting in the decrease OfJcsf from 2.8 to 0.8 ***^-2. Even though Jcsf has not varied monotonically, the critical transition temperature of GdYBCO films linearly increases from 90.75 to 92.25 K and the in-field performance at magnetic field （B） of 0-1.1 T and 77 K as well as B parallel to film normal is also superior with Gd content increasing.

关键词： Gd content GdYBCO MOCVD Microstructure Flux pinning

Compressional behavior of MgCr_2O_4 spinel from first-principles simulation

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Science China Earth Sciences 2016年第5期59卷 989-996页

作者： zhang YanYao LIU Xi xiong ZhiHua zhang ZhiGang Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education of China School of Earth and Space Sciences Peking University Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences

The compressional behavior of the MgCr_2O_4 spinel has been investigated with the CASTEP code using density functional theory and planewave pseudopotential technique. We treated the exchange-correlation interaction by both the local density approximation（LDA） and generalized gradient approximation（GGA） with the Perdew-Burker-Ernzerhof functional. Our simulation was conducted for the pressure range of 0–19 GPa. We obtained the isothermal bulk modulus（K_T） of the MgCr_2O_4 spinel as 181.46（48） GPa（GGA; low boundary） or 216.1（11） GPa（LDA; high boundary）, with its first derivative（K＇_T） as 4.41（6） or 4.5（1）, respectively. The oxygen parameter u is not constant but negatively correlated with P, and decreases by about 0.5–0.6% for the investigated P range. The component polyhedra have different compressibilities, increasing in the order of（O_4）_1

关键词： MgCr_2O_4 spinel Compressional behavior GGA LDA Polyhedral compressibility

单纯性支气管扩张症与支气管扩张症-慢性阻塞性肺疾病重叠综合征患者的病原菌对比研究

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中国全科医学 2025年第6期28卷 729-736页

作者：吴俊张玲顾东伟郑磊赵祝香赵子文安徽省马鞍山市人民医院呼吸与危重症医学科 243000 安徽省马鞍山市人民医院检验科 243000 华南理工大学附属第二医院广州市第一人民医院呼吸与危重症医学科广东省广州市510180

背景我国慢性阻塞性肺疾病(简称慢阻肺)及支气管扩张症(简称支扩)患者数量庞大,均为高发病率、高病死率的慢性呼吸系统疾病。支气管扩张症-慢性阻塞性肺疾病重叠综合征(BCOS)作为一种特殊临床亚型虽常见但易被忽略。感染常是其急性恶化... 详细信息

背景我国慢性阻塞性肺疾病(简称慢阻肺)及支气管扩张症(简称支扩)患者数量庞大,均为高发病率、高病死率的慢性呼吸系统疾病。支气管扩张症-慢性阻塞性肺疾病重叠综合征(BCOS)作为一种特殊临床亚型虽常见但易被忽略。感染常是其急性恶化的诱因,但相关病原学研究相对匮乏。目的分析单纯性支气管扩张症(BE)与BCOS患者病原菌分布、耐药性特点,比较两者差异。为临床合理使用抗菌药物提供参考。方法选取2016年1月—2023年1月在马鞍山市人民医院呼吸与危重医学科住院的支扩患者584例为研究对象,根据是否合并慢阻肺将患者分为两组:BE组(未合并慢阻肺,335例)和BCOS组(合并慢阻肺,249例)。回顾性分析患者病原菌构成、药敏结果及变迁,分析两组病原菌分布及耐药性差异。结果584例支扩患者共分离299株病原菌,BE组分离病原菌146株,其中革兰阴性菌87株(59.59%),革兰阳性菌3株(2.05%),分枝杆菌9株(6.16%),真菌47株(32.19%);BCOS组分离病原菌153株,其中革兰阴性菌80株(52.29%),革兰阳性菌1株(0.65%),分枝杆菌2株(1.31%),真菌70株(45.75%);BCOS组患者白色念珠菌构成比高于BE组(χ^(2)=5.274,P=0.022)。两组铜绿假单胞菌耐药率分别为:亚胺培南10.64%、25.53%,哌拉西林他唑巴坦6.98%、15.91%,环丙沙星12.77%、21.28%,阿米卡星2.13%、2.13%;两组肺炎克雷伯菌耐药率分别为:亚胺培南0、14.29%,哌拉西林他唑巴坦0、14.29%,环丙沙星15.38%、35.71%,阿米卡星0、7.14%;BCOS组铜绿假单胞菌对氨苄西林舒巴坦耐药率低于BE组(P=0.026)。BCOS组患者产超广谱β内酰胺酶肠杆菌科(χ^(2)=4.357,P=0.037)及耐碳青霉烯类铜绿假单胞菌分离率均高于BE组(χ^(2)=5.593,P=0.018)。2016—2022年支扩患者分离铜绿假单胞菌株数均最高,呈先降后升趋势;分离肺炎克雷伯菌株数在2021、2022年明显升高,仅次于铜绿假单胞菌;2020—2022年分离分枝杆菌株数及2021—2022年分离曲霉菌株数均呈上升趋势。结论BCOS作为一种特殊表型,其病原菌分布、耐药性有其自身特点,值得关注。铜绿假单胞菌目前是BE及BCOS患者常见分离致病菌,近年来分离肺炎克雷伯菌株数仅次于铜绿假单胞菌。分离分枝杆菌、曲霉菌株数较前亦明显上升,应引起重视,尤其是BE患者。

关键词：支气管扩张症肺疾病,慢性阻塞性支气管扩张症-慢性阻塞性肺疾病重叠综合征铜绿假单胞菌肺炎克雷伯菌抗药性

Kinetic study of the hydrocarbon generation from marine carbonate source rocks characterization of products of gas and liquid hydrocarbon

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Chinese Science Bulletin 2006年第23期51卷 2885-2891页

作者： GENG Xinhua GENG Ansong xiong Yongqiang LIU Jinzhong zhang Haizu zhao Qingfang The State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

The kinetic parameters of hydrocarbon generation from the marine carbonate source rocks were determined and calibrated through kinetic simulating experiment. The kinetic parameters of hydrocarbon generation then were extrapolated to geological condition by using the relative software. The result shows that gaseous hydrocarbons (C_1, C_2, C_3, C_(4-5)) were generated in condition of 150℃

关键词：烃相生动力学碳酸盐运动模拟地质情况

Series-parallel Hybrid Vehicle Control Strategy Design and Optimization Using Real-valued Genetic Algorithm

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Chinese Journal of Mechanical Engineering 2009年第6期22卷 862-868页

作者： xiong Weiwei YIN Chengliang zhang Yong zhang Jianlong Institute of Automotive Engineering Shanghai Jiao Tong University Shanghai 200240 China

Despite the series-parallel hybrid electric vehicle inherits the performance advantages from both series and parallel hybrid electric vehicle, few researches about the series-parallel hybrid electric vehicle have been revealed because of its complex co nstruction and control strategy. In this paper, a series-parallel hybrid electric bus as well as its control strategy is revealed, and a control parameter optimization approach using the real-valued genetic algorithm is proposed. The optimization objective is to minimize the fuel consumption while sustain the battery state of charge, a tangent penalty function of state of charge（SOC） is embodied in the objective function to recast this multi-objective nonlinear optimization problem as a single linear optimization problem. For this strategy, the vehicle operating mode is switched based on the vehicle speed, and an ＂optimal line＂ typed strategy is designed for the parallel control. The optimization parameters include the speed threshold for mode switching, the highest state of charge allowed, the lowest state of charge allowed and the scale factor of the engine optimal torque to the engine maximum torque at a rotational speed. They are optimized through numerical experiments based on real-value genes, arithmetic crossover and mutation operators. The hybrid bus has been evaluated at the Chinese Transit Bus City Driving Cycle via road test, in which a control area network-based monitor system was used to trace the driving schedule. The test result shows that this approach is feasible for the control parameter optimization. This approach can be applied to not only the novel construction presented in this paper, but also other types of hybrid electric vehicles.

关键词： series-parallel hybrid electric vehicle control strategy design optimization real-valued genetic algorithm

Frustrated Lewis Pairs:Discovery and Overviews in Catalysis

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Chinese Journal of Chemistry 2020年第11期38卷 1360-1370页

作者： Nan Li Wen-xiong zhang Beijing National Laboratory for Molecular Sciences(BNLMS) Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of ChemistryPeking UniversityBeijing 100871China Henan Key Laboratory of Function-Oriented Porous Materials College of Chemistry and Chemical EngineeringLuoyang Normal UniversityLuoyangHenan 471934China

Frustrated Lewis Pairs(FLPs)are derived from simple combinations of Lewis acids(electron acceptors)and Lewis bases(electron donors),in which steric demands prevent from forming classical Lewis acid-base *** 2006,FLP chemistry has emerged as a novel strategy for the design and application of main-group chemistry and development of new metal-free catalytic *** strategy has been applied to stoichiometric reactivity and then extended to *** this review,we briefly summarize the representative discoveries and developments of FLP chemistry in the field of catalysis,including hydrogenation,hydrosilylation,reduction of C 02/transformations of alkynes to organic derivatives,C—H bond borylation and polymerization.

关键词： processes. chemistry bases