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Grain dehydration rate is related to post-silking thermal time and ear characters in different maize hybrids

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Journal of Integrative Agriculture 2022年第4期21卷 964-976页

作者： shi wen-jun SHAO Hui SHA Ye shi Rong shi Dong-feng CHEN Ya-chao BAN Xiang-ben MI Guo-hua The Key Lab of Plant–Soil Interaction Ministry of Education/National Academy of Agriculture Green Development/College of Resources and Environmental ScienceChina Agricultural UniversityBeijing 100193P.R.China

Mechanized grain harvest of maize becomes increasingly important with growing land plot size in Northeast China. Grain moisture is an important factor affecting the performance of mechanized grain harvest. However, it remains unclear what influences grain dehydration rate. In this study, maize grain dehydrating process was investigated in a two-year field experiment with five hybrids under two planting densities in 2017 and 2018. It was found that damaged-grain ratio was the main factor affecting mechanized harvest quality, and this ratio was positively correlated with grain moisture content at harvest(R^(2)=0.6372, Pship between GDDs and grain moisture still existed, but the correlation coefficient became smaller(r=-0.8267, P<0.01). At this stage, grain dehydrating process was greatly affected by genotypes. Grain dehydrated faster when a hybrid has a smaller husk area(r=0.6591, P<0.05), larger ear angle(r=-0.7582, P<0.05), longer ear peduncle(r=-0.9356, P<0.01) and finer ear(r=0.9369, P<0.01). These parameters can be used for breeders and farmers to select hybrids suitable for mechanized grain harvest.

关键词： maize grain moisture grain dehydrating grain damage mechanized harvest ear traits genotype

石河子市规模牛场三个品系牛BVD-MD血清学监测

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中国奶牛 2024年第7期 61-65页

作者：林为民石国旺史文军王丹黄新新疆兵团第八师畜牧兽医工作站石河子832000 石河子大学动物科技学院石河子832000 新疆农垦科学院石河子832000

针对石河子市部分规模牛场临床出现的早产、流产、弱胎、犊牛腹泻等症状,进行了牛病毒性腹泻/黏膜病(BVD-MD)血清学调查,旨在掌握该病感染状况和品系间牛发生犊牛腹泻和成母牛早产等疾病之间差异,为防控净化BVD-MD提供参考。选择石河子... 详细信息

针对石河子市部分规模牛场临床出现的早产、流产、弱胎、犊牛腹泻等症状,进行了牛病毒性腹泻/黏膜病(BVD-MD)血清学调查,旨在掌握该病感染状况和品系间牛发生犊牛腹泻和成母牛早产等疾病之间差异,为防控净化BVD-MD提供参考。选择石河子市范围内3个未免疫BVD-MD疫苗牛场,分别饲养中国荷斯坦牛(以下简称荷牛),弗莱维赫乳肉兼用牛×荷斯坦牛杂交代乳肉兼用牛(以下简称弗荷牛),挪威红牛×荷斯坦牛杂交代乳肉兼用牛(以下简称挪荷牛);共计采集血清样品2 981份,分别使用牛病毒性腹泻(BVD)实时荧光RT-PCR监测和牛病毒性腹泻ELISA方法监测抗原和抗体。并通过临床观察记录三个品系牛发病情况,分析品系间发病的差异。实时荧光RT-PCR监测抗原阳性总检出率为1.85%(55/2981),荷牛阳性检出率为2.17%,弗荷牛阳性检出率为1.35%,挪荷牛阳性检出率为2.05%;品系之间抗原阳性率差异不显著(P>0.05);三个品系的犊牛、青年牛、后备牛、成母牛均监测到BVDV,说明BVDV感染不因品系不同而存在差异,不同品系牛之间不影响BVDV的流行。牛病毒性腹泻ELISA方法监测阳性总检出率为28.75%,荷牛阳性检出率为32.85%,弗荷牛阳性检出率为28.06%,挪荷牛阳性检出率为25.41%;三个品系牛之间抗体阳性率差异不显著(P>0.05)。分析三个品系牛临床发病(犊牛腹泻与成母牛早产、流产、弱胎等)数据显示:弗荷犊牛与挪荷犊牛腹泻发病率较荷犊牛发病率差异极显著(P0.05);二是弗荷牛和挪荷牛较荷牛有更强的抵抗疾病的能力。监测结果为石河子市规模牛场BVD-MD的防控和净化工作提供了技术支撑。

关键词：规模牛场三个品系牛 BVDV 血清学监测

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犊牛布鲁氏菌病疫苗首免时间探讨

中国奶牛 2024年第5期 34-37页

作者：吴庆李怡林为民侯宇成史文军新疆兵团第八师134团农业发展服务中心石河子832000 新疆兵团第八师畜牧兽医工作站石河子832000

本文旨在探讨犊牛布鲁氏菌病活疫苗(A19株)的首免时间,了解其体液免疫应答抗体消长规律,以期制定本地区布鲁氏菌病活疫苗免疫程序。选择新疆10个规模奶牛场(成年奶牛700头以上)的1~12日龄试验犊牛1306头,不间断试验至12月龄;观察疫苗免... 详细信息

本文旨在探讨犊牛布鲁氏菌病活疫苗(A19株)的首免时间,了解其体液免疫应答抗体消长规律,以期制定本地区布鲁氏菌病活疫苗免疫程序。选择新疆10个规模奶牛场(成年奶牛700头以上)的1~12日龄试验犊牛1306头,不间断试验至12月龄;观察疫苗免疫前后牛的健康状况、实际操作中主要免疫牛群的集中度,并监测免疫前犊牛母源抗体消长及不同月龄免疫后抗体消长规律;并结合多年临床操作实践(便于工作操作而主要选择的免疫时间点、环境气候)及性器官成熟期前、产犊时间、犊牛数量、人员安排等情况进行总结分析。结果显示,免疫后犊牛是安全的;免疫前犊牛母源抗体在5月龄时已近为零,3~5月龄免疫的牛体液免疫应答更强。因此建议布鲁氏菌病活疫苗(A19株)犊牛首免时间选择在3~5月龄为宜。

关键词：犊牛布鲁氏菌病疫苗安全体液免疫首免时间探讨

规模化奶牛场常发高害疾病的流行病学调查与思考

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中国奶牛 2024年第1期 26-30页

作者：林为民冯闯刘强侯宇成史文军新疆生产建设兵团第八师畜牧兽医工作站石河子832000 新疆生产建设兵团第八师石河子石总场农业发展服务中心石河子832000

2018年10月~2022年7月期间,为掌握新疆生产建设兵团第八师石河子市规模化牛场奶牛常发高害疾病的发生情况,课题组对某大型国有公司所属的6个规模化奶牛场临床发病病种及发病情况进行了不间断的流行病学调查。共调查各生长阶段的奶牛9541... 详细信息

2018年10月~2022年7月期间,为掌握新疆生产建设兵团第八师石河子市规模化牛场奶牛常发高害疾病的发生情况,课题组对某大型国有公司所属的6个规模化奶牛场临床发病病种及发病情况进行了不间断的流行病学调查。共调查各生长阶段的奶牛9541头,临床常发高害疾病主要有犊牛腹泻、犊牛支气管肺炎、蹄病、乳房炎、酮病、酸中毒、产科病(子宫内膜炎、胎衣不下、卵巢疾患)等,年总平均发病率为7.85%;其中:犊牛腹泻发病率最高,平均发病率为19.10%;其次是成母牛蹄病,平均发病率为15.05%;再次是酮病,平均发病率为5.76%;产科疾病发病率最低,平均发病率为2.11%。从营养平衡、气候环境和防治能力等方面探寻了致病的主要原因,以期为降低疾病造成的危害、助力石河子市奶牛业高质量发展提供技术支撑。

关键词：规模化奶牛场常发高害疾病流行病学调查腹泻蹄病乳房炎酮病瘤胃酸中毒产科病

Characterization of the current crowding effect on chip surface using a quantum wide-field microscope

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Chinese Optics Letters 2024年第6期22卷 123-128页

作者： Rui Zhao Ding Wang Huan Fei wen Yunbo shi jun Tang jun Liu Science and Technology on Electronic Test&Measurement Laboratory North University of ChinaTaiyuan 030051China

We characterize the current crowding effect for microwave radiation on a chip surface based on a quantum wide-field microscope combining a wide-field reconstruction technique. A swept microwave signal with the power of 0–30 d Bm is supplied to a dumbbell-shaped microstrip antenna, and the significant differences in microwave magnetic-field amplitudes attributed to the current crowding effect are experimentally observed in a 2.20 mm ×1.22 mm imaging area. The normalized microwave magnetic-field amplitude along the horizontal geometrical center of the image area further demonstrates the feasibility of the characterization of the current crowding effect. The experiments indicate the proposal can be qualified for the characterization of the anomalous area of the radio-frequency chip surface.

关键词： current crowding effect microwave field on chip surface quantum wide-field microscope nitrogen-vacancy center

Recent advances in vacancy engineering for reliable lithiumsulfur batteries

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Rare Metals 2024年第2期43卷 455-477页

作者： wen-Dong Liu Xiao Tang jun-An Feng Chao-Yue Zhang Hao Liu Chuan shi Xiao-Xian Zhao Jian-jun Song College of Physics School of Chemistry and Chemical EngineeringQingdao UniversityQingdao266071China Faculty of Science Centre for Clean Energy TechnologySchool of Mathematical and Physical SciencesUniversity of Technology SydneySydneyNSW2007Australia Department of Chemistry College of ScienceHebei Agricultural UniversityBaoding071001China

The high-energy-density and low-cost features endow lithium-sulfur batteries with broad application ***,many drawbacks,especially the detrimental shuttle effect,have hindered the further development of *** response,a lot of new structures have been applied to suppress the shuttle effect and promote the development of ***,vacancy engineering has gained the attention of researchers due to its unique electronic *** review aims to analyze the application of vacancy engineering in ***,the electrochemistry of LSBs has been systematically discussed and the existing challenges as well as improvement tactics of LSBs have also been ***,the preparation methods and characterization technologies of various vacancies are summarized,including oxygen vacancies,sulfur vacancies,selenium vacancies,other anion vacancies,cation vacancies,*** latest applications of vacancy engineering in LSBs are also summarized in this ***,some prospects and insights for further investigation and practical application of vacancy engineering in LSBs are put forward.

关键词： Lithium-sulfur batteries(LSBs) Defects Vacancy engineering Electronic structure Shuttle effect

Adhesive Contact of Elastic Solids with Self-Affine Fractal Rough Surfaces

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Acta Mechanica Solida Sinica 2024年第2期37卷 265-270页

作者： Xuan-Ming Liang shi-wen Chen Si-He Wang Zhen-Yuan Gong jun Feng Gang-Feng Wang Department of Engineering Mechanics SVL and MMMLXi’an Jiaotong UniversityXi’an710049China OPPO Mobile Telecommunications Corporation Ltd. Dongguan523860China

The elastic adhesive contact of self-affine fractal rough surfaces against a rigid flat is simulated using the finite element method. An array of nonlinear springs, of which the force-separation law obeys the Lennard–Jones potential, is introduced to account for the interfacial adhesion. For fractal rough surfaces, the interfacial interaction is generally attractive for large mean gaps, but turns repulsive as the gap continuously shrinks. The interfacial interactions at the turning point corresponding to the spontaneous contact are shown for various surfaces. For relatively smooth surfaces, the probability density distributions of repulsion and attraction are nearly symmetric. However, for rougher surfaces, the simulation results suggest a uniform distribution for attraction but a monotonously decreasing distribution with a long tail for repulsion. The pull-off force rises with increasing ratio of the work of adhesion to the equilibrium distance, whereas decreases for solids with a higher elastic modulus and a larger surface roughness. The current study will be helpful for understanding the adhesion of various types of rough solids.

关键词： Fractal rough surfaces Adhesion Contact mechanics Lennard-Jones potential

半山区滑坡灾害危险性评价——GIS支持下基于Kuenm包优化Maxent模型

维普期刊数据库评论

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地质灾害与环境保护 2024年第3期35卷 1-10页

作者：解晋航石文君张杰张小亮李章杰王宇栋昆明理工大学公共安全与应急管理学院昆明650093 自然资源部高原山地地质灾害预报预警与生态保护修复重点实验室昆明650051

根据会泽县地处云贵高原半山区的地理环境特点,以滑坡灾害为研究对象,选取地貌、坡度、坡向、曲率、地形起伏度、降雨量、距道路距离、斜坡结构、高程9个评价因子,基于相关性分析和共线性诊断对其进行独立性检验。采用优化Maxent模型与... 详细信息

根据会泽县地处云贵高原半山区的地理环境特点,以滑坡灾害为研究对象,选取地貌、坡度、坡向、曲率、地形起伏度、降雨量、距道路距离、斜坡结构、高程9个评价因子,基于相关性分析和共线性诊断对其进行独立性检验。采用优化Maxent模型与加权信息量模型计算滑坡发生概率。基于GIS的自然间断法评价结果等级,通过合理性检验、敏感性检验及现场实地检验比较两种模型的合理性及准确性。结果表明:两种评价模型均能通过合理性检验,AUC值分别为0.902和0.769,优化Maxent模型精度更高,通过刀切法得出距道路距离因子贡献百分比最高,与野外调查的典型灾害点主要影响因子相吻合,其稳定、低、中和高的面积分别为1585.74 km^(2)(26.70%)、2138.42 km^(2)(36.90%)、1594.48 km^(2)(26.85%)和567.37 km^(2)(9.55%)。

关键词：半山区滑坡优化Maxent模型加权信息量模型

Resource allocation based on genetic algorithm for multi-hop OFDM system with non-regenerative relaying

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The Journal of China Universities of Posts and Telecommunications 2009年第5期16卷 25-32页

作者： shi Jie , XU wen-jun, HE Zhi-qiang, NIU Kai, WU Wei-ling School of Information and Telecommunication Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, China School of Information and Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

This article investigates resource allocation in multi-hop orthogonal frequency division multiplexing （OFDM） system with amplifying-and-forwarding relaying to maximize the end-to-end capacity, Most existing methods for multi-hop system focus on power allocation or subcarrier selection separately, but joint resource allocation is rarely considered due to the absence of effective interaction schemes. In this work, a novel joint resource allocation methodology is proposed based on Partheno genetic algorithm （PGA）, which produces excellent subcarrier allocation set （referred to as individual in PGA） with higher capacity by evolution operator generation by generation. In addition, an adaptive power allocation is also designed to evaluate the fitness of PGA and further enhance the system capacity. Both theoretical analysis and simulated results show the effectiveness of the proposed joint strategy. It outperforms the traditional method by as much as 40% capacity improvement for 3-hop relaying system when system power is high, and obtains much more capacity enhancement percent under conditions of low system power.

关键词： multi-hop OFDM system non-regenerative relaying genetic algorithm power allocation subcarrier selection resource allocation