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温室辣椒自动补苗机构控制系统设计与试验

农机化研究 2024年第1期46卷 67-74页

作者：缪宏李孟丽徐浩童俊华张善文戴敏扬州大学机械工程学院江苏扬州225000 浙江理工大学机械与自动控制学院杭州310000

针对辣椒培育过程中会出现一定量劣苗影响穴盘苗一致性,且目前移栽机械自动化程度低、移栽效果不理想的问题,依照农艺要求规范设计了机-电-气一体的自动补苗机构控制系统。阐述了自动补苗机构工作原理和系统结构,结合传感器和执行器布... 详细信息

针对辣椒培育过程中会出现一定量劣苗影响穴盘苗一致性,且目前移栽机械自动化程度低、移栽效果不理想的问题,依照农艺要求规范设计了机-电-气一体的自动补苗机构控制系统。阐述了自动补苗机构工作原理和系统结构,结合传感器和执行器布局和剔补苗运行机制设计了补苗机构控制系统软件和硬件。参照移栽手工作要求,设计气路系统并进行相关计算。对45天辣椒幼苗进行移栽补苗试验,以水平移动速率、取苗深度、含水率为试验因子,剔苗成功率、移栽成功率为衡量指标,设计三因素三水平正交试验,结果表明:水平移栽速率对剔苗成功率和移栽成功率影响较小,移栽手运行平稳,剔苗成功率平均值为94%,移栽成功率为91.1%,表明自动补苗机构性能可靠。

关键词：辣椒补苗移栽控制系统

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Partition Equilibrium on the Interface Between a Charged Membrane and a Mixed Electrolyte Aqueous Solution

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Chemical Research in Chinese Universities 2003年第1期19卷 63-69页

作者： XU tong wen YANG Wei hua Department of Chemistry University of Science and Technology of ChinaHefei 230026P.R.China

Ionic partition equilibrium on a charged membrane immersed in a mixed electrolyte solution was systematically investigated and several models were established for the determination of partition coefficients. On the basis of theoretical models, the effects of the concentration ratio λ of the fixed group(charged density) to reference electrolyte, the concentration ratio η between the two electrolytes existing in the solution and the valence of the electrolyte ions on the partition equilibrium in a positively charged membrane were analyzed and simulated within the chosen parameters in detail. The obtainable results can also be applicable to a sytem of mixed electrolytes contacting with a negatively charged membrane. The theoretical calculations were confirmed with the experimental data of model mixed electrolytes, NaCl+HCl and CaCl 2+NaCl partitioned in the system of self made negatively charged membrane sulphonated poly(phenylene oxide)(SPPO) with different charge densities.

关键词： Partition coefficient Donnan equilibrium Mixed electrolyte Charged membrane

Thermodynamic Analysis of Formation of Low-carbon Olefins via Coal Gasification Coupling C_1 Reaction

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China Petroleum Processing & Petrochemical Technology 2018年第3期20卷 24-31页

作者： Xu Jing Tu Nan Liu tong College of Mechanical and Electrical Engineering Xi'an Polytechnic University

The complex reaction system of the coal gasification coupling C1 reaction was analyzed based on the principles of thermodynamics. The results show that an increase in the temperature is beneficial to the generation of hydrocarbons with high carbon-atom contents, in which the alkane yield is higher than the alkene yield. The complex reaction system consisting of C, H20, CO, CO2, H2, C2H4, C3H6 and C4Hs was studied, and the obtained results indicated that when the maximum mole fraction content of C2-C4 olefins was regarded as the optimized objective function, the optimum temperature was approximately 648 K, the pressure was 0.1 MPa, the feed ratio was approximately 0.6, and the maximum mole fraction content of C2-C4 olefins was approximately 28.24%. The thermodynamic simulation and calculation of the complex reaction system can provide a basis for the determination and optimization of actual process conditions and are therefore of great theoretical and practical significance.

关键词： thermodynamic analysis low-carbon olefins coal gasification coupling C1 reaction

考虑瓦块子结构的可倾瓦轴承广义完整动特性系数研究

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轴承 2024年第3期 9-20页

作者：闫岗刘洋洋齐洪柱佟晓敏袁小阳中国工程物理研究院材料研究所四川绵阳621907 西安交通大学现代设计及转子轴承系统教育部重点实验室西安710049

针对因忽略瓦块子结构动力学特性而导致常规8系数无法分析瓦块摆振特性及其稳定性的问题,提出考虑瓦块子结构的可倾瓦轴承广义完整动特性系数表征方法。以瓦间承载的四瓦可倾瓦轴承为研究对象,采用差分概念法计算了其广义完整动特性系数... 详细信息

针对因忽略瓦块子结构动力学特性而导致常规8系数无法分析瓦块摆振特性及其稳定性的问题,提出考虑瓦块子结构的可倾瓦轴承广义完整动特性系数表征方法。以瓦间承载的四瓦可倾瓦轴承为研究对象,采用差分概念法计算了其广义完整动特性系数,利用线性和非线性方法计算得到的小扰动响应对比验证了计算模型的正确性,研究了轴承结构参数和运行工况对可倾瓦轴承动特性系数的影响规律。研究结果表明:承载瓦的稳定性高于非承载瓦;重载工况下非承载瓦易发生失稳故障;转速过高会降低转子轴承系统的减振能力;存在一个最佳支点系数可以使各瓦块的角刚度最大;增大长径比、预载荷系数和瓦包角,减小轴承间隙比可以提高轴承的刚度系数、阻尼系数以及各瓦块的角刚度系数、角阻尼系数,轴承间隙对动特性系数的影响最显著。

关键词：滑动轴承可倾瓦轴承动稳定性承载能力刚度系数阻尼系数

CP800高强钢高速激光焊接接头组织与性能研究

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钢铁钒钛 2024年第3期45卷 182-187页

作者：姜彤王大锋邹升光曾浩林马冰陈东高中国兵器科学研究院宁波分院浙江宁波315103

为了进一步提高激光焊接速度,改善高速焊接过程中焊缝凹陷的问题,对CP800高强钢进行了12 m/min的高速激光焊接,研究了激光入射角对焊缝成形的影响。在最优焊接工艺参数下,对焊缝成形、焊缝质量、焊接接头组织、硬度及力学性能进行了研... 详细信息

为了进一步提高激光焊接速度,改善高速焊接过程中焊缝凹陷的问题,对CP800高强钢进行了12 m/min的高速激光焊接,研究了激光入射角对焊缝成形的影响。在最优焊接工艺参数下,对焊缝成形、焊缝质量、焊接接头组织、硬度及力学性能进行了研究。结果表明:当激光入射角度为+10°时,焊缝表面基本无飞溅,凹陷最小。此外在激光功率为12500 W,焊接速度为12 m/min,激光入射角为+10°的最佳焊接参数下,焊缝表面及内部质量较好,焊缝熔宽约为1.15 mm,热影响区宽度约为0.35 mm。焊缝组织中,主要存在的是板条状马氏体和针状铁素体以及极少量的粒状贝氏体。焊缝的显微硬度(HV)值在402.5~408.5。焊接接头抗拉强度能够达到母材抗拉强度的96%,焊接接头室温冲击功能够达到母材室温冲击功的87.5%。

关键词： CP800高强钢高速激光焊激光入射角显微组织力学性能

ANALYSIS OF SOLUBLE CHEMICAL TRANSFER BY RUNOFF WATER IN FIELD

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Journal of Hydrodynamics 2008年第3期20卷 382-390页

作者： tong Ju-xiu YANG Jin-zhong State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan430072 China

In order to determine the main factors influencing soluble chemical transfer and corresponding techniques for reducing fertilizer loss caused by runoff in irrigated fields, a physically based two-layer model was developed with incomplete mixing theory. Different forms of incomplete mixing parameters were introduced in the model, which was successfully verified with previous published experimental data. According to comparison, the chemicals loss of fertilizer is very sensitive to the runoff-related parameter while it is not sensitive to the infiltration-related parameter. The calculated results show that the chemicals in infiltration water play an important role in the early time of rainfall even with saturated soil, and it is mainly in the runoff flow in the late rainfall. Therefore, prevention of shallow subsurface drainage in the early rainfall is an effective way to reduce fertilizer loss, and the coverage on soil surface is another effective way.

关键词： soluble chemical transfer runoff incomplete mixing sensitive infiltration

公里网格尺度的陕西冬小麦综合遥感指数保险产品设计

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中国农业气象 2024年第10期45卷 1204-1215页

作者：陈妍薛子怡王彤王东姬便便西北农林科技大学经济管理学院杨凌712100

基于遥感时序数据MOD13A2和陕西省99个气象站点的逐日气象数据,使用EVI差值法提取陕西冬小麦种植区,筛选与冬小麦单产相关性最高的遥感指数,结合冬小麦生育期内倒春寒、干旱、连阴雨以及干热风4个农业气象灾害的气象指标,构建综合遥感... 详细信息

基于遥感时序数据MOD13A2和陕西省99个气象站点的逐日气象数据,使用EVI差值法提取陕西冬小麦种植区,筛选与冬小麦单产相关性最高的遥感指数,结合冬小麦生育期内倒春寒、干旱、连阴雨以及干热风4个农业气象灾害的气象指标,构建综合遥感指数模型,以覆盖冬小麦全生育期的农业气象灾害风险。基于最优产量预测模型设计冬小麦综合遥感指数保险,采用分布拟合和蒙特卡洛模拟方法,计算10770个公里网格冬小麦综合遥感指数保险的理赔门槛值和精算纯费率,绘制理赔门槛地图和精算纯费率地图。结果表明:(1)采用EVI差值法提取冬小麦种植区,不同区域使用不同差值时段和门槛值,可获得较高提取精度,县域提取面积与2020年实际播种面积的相关系数达0.997,平均绝对误差524.9hm²;(2)2000-2020年第65、81天EVI及两者最大值与陕西冬小麦单产相关性较高,县域相关系数年平均值最高达0.692;(3)融合干旱、连阴雨和倒春寒3个农业气象灾害的气象指标,最优综合遥感指数模型模拟单产与实际单产的相关系数达0.837,最优综合遥感指数模型R²为0.602;(4)关中、陕南部分地区冬小麦种植风险较低,平均单产损失率低于2%,渭河与黄河交口处冬小麦种植风险较高,平均单产损失率高于4%,其余地区冬小麦种植风险介于两者之间。冬小麦单产和种植风险在县域以下区域存在较大空间差异,提高测算理赔门槛和精算纯费率的空间精度,能够使冬小麦高产地区和低产地区获得同样的赔付机会,避免赔付超过实际损失导致的道德风险,同时能够使费率与实际种植风险相匹配,增加费率公平性,提高低风险地区参保意愿,减少逆选择。

关键词：遥感指数保险冬小麦费率厘定 EVI

Early renal injury indicators can help evaluate renal injury in patients with chronic hepatitis B with long-term nucleos(t)ide therapy

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World Journal of Clinical Cases 2020年第24期8卷 6306-6314页

作者： tong-tong Ji Ning Tan Hai-Ying Lu Xiao-Yuan Xu Yan-Yan Yu Department of Infectious Diseases Peking University First HospitalBeijing 100034China

BACKGROUND Patients with chronic hepatitis B(CHB)with long-term nucleos(t)ide therapy may experience renal *** renal function indicators,such as urine protein,serum urea nitrogen(BUN),and serum creatinine,are normal when early mild lesions ***,more sensitive renal function indicators are *** To investigate the significance of early renal injury indicators in evaluating renal injury in patients with CHB with long-term nucleos(t)ide *** We collected the clinical data of 69 outpatients with CHB at Peking University First Hospital from March 2018 to January 2020 who had been treated with longterm nucleos(t)ide therapy and analyzed the results of early renal injury *** normal distribution data were analyzed by the t-test to determine the difference between two *** non-normally distributed data were analyzed by the Mann-Whitney U-test between two *** Kruskal-Wallis H test was used to determine the differences among multiple *** data were analyzed by the chi-square *** related factors of early renal injury indicators were analyzed by logistic regression *** The average treatment duration with nucleos(t)ide analogs of the 69 patients with CHB was 99.7±28.7 *** cases of patients with elevated BUN and hypophosphatemia were 6(8.7%)and 13(18.8%),respectively;31(44.9%)patients had abnormal early renal injury indicators,including 9 patients with abnormal urine microalbumin,7 patients with abnormal urine immunoglobulin,6 patients with abnormal urine transferrin,and 19 patients with abnormalα1 *** were no significant differences in the mean values of age,sex,BUN,estimated glomerular filtration rate(eGFR),serum uric acid,serum calcium,or serum phosphorus between the two groups of patients with and without early renal injury ***,the mean levels of serum creatinine and urine creatinine,N-acetyl-β-D-glucosidase enzyme,α1 microglo

关键词： Early renal injury Chronic hepatitis B Nucleos(t)ide analog N-acetyl-β-Dglucosidase enzyme α1 microglobulin Urine immunoglobulin

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核电厂联氨应用的探讨

核科学与工程 2024年第1期44卷 63-69页

作者：于淼曾晓敏顾钰万维进武铜上海核工程研究设计院股份有限公司上海200233

为了控制系统设备和结构材料的腐蚀,核电厂一回路和二回路冷却剂系统均维持弱碱还原性水化学环境。联氨为一回路和二回路主要的化学添加剂,因其还原性,主要用来除氧、钝化、冲洗、缓蚀、事故后除碘等。本文介绍了核电厂中联氨的主要用途... 详细信息

为了控制系统设备和结构材料的腐蚀,核电厂一回路和二回路冷却剂系统均维持弱碱还原性水化学环境。联氨为一回路和二回路主要的化学添加剂,因其还原性,主要用来除氧、钝化、冲洗、缓蚀、事故后除碘等。本文介绍了核电厂中联氨的主要用途,并分别就一回路除氧、AVT(R)除氧、二回路冲洗钝化、蒸汽发生器湿保养、事故后除碘等展开讨论,最后针对联氨应用中存在的问题给出建议。

关键词：核电厂联氨钝化除氧除碘