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河南科技 2024年第13期51卷 46-49页

作者：杜进朝龙声德曾诚张江平贵州松河煤业发展有限责任公司贵州六盘水553000

【目的】研究工作面推进超前支承压力演化规律及巷道围岩失稳机制。【方法】以某采煤工作面为例,采用弹塑性力学理论分析工作面推进过程中超前支承压力变化特征,探讨超前支承压力作用下的关键层理论,在整个失稳过程中起到关键作用,运用3... 详细信息

【目的】研究工作面推进超前支承压力演化规律及巷道围岩失稳机制。【方法】以某采煤工作面为例,采用弹塑性力学理论分析工作面推进过程中超前支承压力变化特征,探讨超前支承压力作用下的关键层理论,在整个失稳过程中起到关键作用,运用3DEC模拟研究超前支承压力影响下巷道围岩失稳破坏特征。【结果】结果表明,巷道围岩呈现非对称变形,尤其是两帮的非对称变形表现最为显著。随着采矿工作的进行,巷道围岩受到叠加应力的扰动影响,超前支承压力对巷道顶板和两帮的影响差异化主要是由于顶板岩层的硬度较高,煤体相对岩层来说较为松软破碎,以及帮部已经提前产生裂隙,能够释放掉部分顶板压力。【结论】研究结果对于提高系统的稳定性和可靠性具有重要的意义,为预防和管理失稳提供了参考。

关键词：支承压力失稳机理数值分析关键层理论

Downwash airflow field distribution characteristics and their effect on the spray field distribution of the DJI T30 six-rotor plant protection UAV

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International Journal of Agricultural and Biological Engineering 2023年第2期16卷 10-22页

作者： Haiyan zhang Sheng Wen Chunling Chen Qi Liu Tongyu Xu shengde Chen Yubin Lan College of Information and Electrical Engineering Shenyang Agricultural UniversityShenyang 110866China College of Engineering South China Agricultural UniversityGuangzhou 510642China College of Agricultural Engineering and Food Science Shandong University of TechnologyZibo 255022ShandongChina College of Electronic Engineering(College of Artificial Intelligence) South China Agricultural UniversityGuangzhou 510642China National Center for International Collaboration Research on Precision Agricultural Aviation Pesticides Spraying Technology Guangzhou 510642China

Spray characteristics are the fundamental factors that affect droplet transportation downward,deposition,and *** downwash airflow field of the Unmanned Aviation Vehicle(UAV)primarily influences droplet deposition and drift by changing the spray *** study focused mainly on the effect of the downwash airflow field of the UAV and nozzle position on the droplet spatial distribution and velocity distribution,which are two factors of spray *** study the abovementioned characteristics,computational fluid dynamics based on the lattice Boltzmann method(LBM)was used to simulate the downwash airflow field of the DJI T30 six-rotor plant protection UAV at different rotor rotational speeds(1000-1800 r/min).A particle image velocimetry system(PIV)was utilized to record the spray field with the downwash airflow field at different rotational speeds of rotors(0-1800 r/min)or different nozzle positions(0,0.20 m,0.35 m,and 0.50 m from the motor).The simulation and experimental results showed that the rotor downwash airflow field exhibited the‘dispersion-shrinkage-redispersion’development *** the initial dispersion stage of rotor airflow,there were obvious high-vorticity and low-vorticity regions in the rotor downwash airflow ***,the low-vorticity region was primarily concentrated below the motor,and the high-vorticity region was mainly focused in the middle area of the ***,the Y-direction airflow velocity fluctuated at 0.4-1.2 m under the *** the rotor airflow developed to 3.2 m below the rotor,the Y-direction airflow velocity showed a slight *** 3.2 m from the rotor,the Y-direction airflow velocity started to drastically ***,it is recommended that the DJI T30 plant protection UAV should not exceed 3.2 m in flight height during field spraying *** rotor downwash airflow field caused the nozzle atomization angle,droplet concentration,and spray field width to decrease while inc

关键词： downwash airflow spray field distribution plant protection UAV characteristics

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复合菌种发酵青稞面团工艺优化

食品研究与开发 2024年第2期45卷 112-117页

作者：阿晟德陈啟蓉张生梅曹效海王树林青海大学农牧学院青海西宁810016 青海大学省部共建三江源生态与高原农牧业国家重点实验室青海西宁810016

该文研究复合菌种发酵对青稞面团质构特性的影响。以青稞粉和高筋小麦粉为原料,pH值和持气性为指标,筛选最佳发酵菌种组合;以硬度、弹性为指标,采用单因素试验考察发酵时间、复合菌种接种量、复合菌种质量比和青稞粉添加量对面团特性的... 详细信息

该文研究复合菌种发酵对青稞面团质构特性的影响。以青稞粉和高筋小麦粉为原料,pH值和持气性为指标,筛选最佳发酵菌种组合;以硬度、弹性为指标,采用单因素试验考察发酵时间、复合菌种接种量、复合菌种质量比和青稞粉添加量对面团特性的影响,并采用正交试验优化复合菌种发酵青稞面团工艺。结果表明,最佳发酵工艺为发酵时间2.0 h、复合菌种接种量2.5%、菌种(高活性干酵母∶植物乳杆菌)质量比3∶2、青稞粉添加量30%。该条件下面团弹性较好、硬度较低,具有发酵的香气以及较浓厚的青稞风味,适合用于制作烘焙产品。

关键词：发酵复合菌种质构特性青稞粉青稞面团

SWOT Analysis and Development Strategies for Chinese Farmers' Professional Cooperatives

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Journal of Northeast Agricultural University(English Edition) 2010年第1期17卷 90-96页

作者： zhang Ning HU shengde College of Economics and Management Northeast Agricultural University Harbin 150030 China

With the development of China＇s market economy, the agricultural products＇ market has changed from the seller＇s market into the buyer＇s market. Therefore, the limitations of the household contract responsibility system gradually appeared. The farmers professional cooperatives not only covered the limitations but also effectively connected the small-scale farmers with the competitive market by increasing the farmers＇ organizational degree. However, during the development process of farmers＇ professional cooperatives, many problems were exposed. By using SWOT analysis belonging to the field of enterprise strategic management, this paper discussed the opportunities and threats of the external environment, as well as the strengths and weaknesses of the internal environment of Chinese farmers＇ professional cooperatives. Thereby, it proposed some development strategies for Chinese farmers professional cooperatives in the current stage .

关键词： farmers' professional cooperatives SWOT analysis agricultural microorganization

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实验性Ⅲ度烧伤休克期狗某些激素的变化

解放军医学杂志 1984年第6期 408-410页

作者：杜风鸣冯振康方之杨葛绳德周岱云张璞孟垂祥第二军医大学第一附属医院第二军医大学训练部

观察10只Ⅲ度烧伤休克期狗激素的变化。结果表明:血浆皮质醇含量,烧伤后2小时升高,6小时升至最高,为烧伤前6倍左右(p<0.05)。血清胰岛素和胃泌素含量,烧伤后2小时下降,10小时降至最低,分别为烧伤前的1.5％和33.3％左右。血浆肾素活性和... 详细信息

观察10只Ⅲ度烧伤休克期狗激素的变化。结果表明:血浆皮质醇含量,烧伤后2小时升高,6小时升至最高,为烧伤前6倍左右(p<0.05)。血清胰岛素和胃泌素含量,烧伤后2小时下降,10小时降至最低,分别为烧伤前的1.5％和33.3％左右。血浆肾素活性和血管紧张素Ⅱ,烧伤后2小时升高,以后继续升高,48小时仍升高,分别为烧伤前的10和5倍。

关键词：胃泌素胰岛素烧伤休克多肽休克期 Ⅲ度烧伤血浆皮质醇激素

高原地区海兰褐蛋鸡产蛋期自配复合预混料配方的筛选试验

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青海畜牧兽医杂志 2024年第1期54卷 43-46,50页

作者：张焕邦李春花樊世青保生德闫占云汪生花西宁市湟中区畜牧兽医站青海湟中811600 青海大学畜牧兽医科学院青海西宁810016 青海德佳农牧科技有限公司湟中德佳种养殖专业合作社青海湟中811600

为研究获得高原地区海兰褐蛋鸡的最佳复合预混料配方,本试验选用海兰褐蛋鸡10 000羽,将其随机分为4组,每组2 500羽,试验组A、B、C分别饲喂低、中、高营养水平的自配预混料,对照组D饲喂商品料,并统计各组18~60周龄的产蛋量、产蛋率、平... 详细信息

为研究获得高原地区海兰褐蛋鸡的最佳复合预混料配方,本试验选用海兰褐蛋鸡10 000羽,将其随机分为4组,每组2 500羽,试验组A、B、C分别饲喂低、中、高营养水平的自配预混料,对照组D饲喂商品料,并统计各组18~60周龄的产蛋量、产蛋率、平均蛋重及死淘率。结果表明,A组产蛋量、产蛋率、平均蛋重及成活率均最高;C组在产蛋量、平均蛋重和累计死亡率方面均优于D组和B组;B组仅产蛋率较高,累计死亡率排在第2。在海兰褐蛋鸡无抗养殖中,A组的复合预混料配方是最佳配方。

关键词：海兰褐蛋鸡高原地区自配复合预混料优化

Sequence Stratigraphy and Tectonic Environment of the Chartai Group,Inner Mongolia

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Acta Geologica Sinica(English Edition) 1991年第3期65卷 217-235,341-342页

作者： Qiao Xiufu Yao Peiyi Wang Chengshu Tan Lin Zhu Shenyu Zhou shengde zhang Yuqing Institute of Geology,Chinese Academy of Geological Sciences, Beijing Regional Geological Survey Party,Geological Bureau of Inner Mongolia,Hohhot Sun Sheping Institute of Geology Chinese Academy of Geological Sciences Beijing China

The Middle Proterozoic Chartai Group separated by two unconformities consists of three depositional se-quences: the Shujigou Formation-Zenglongchang Formation (DS Ⅰ), the Agulugou Formation (DS Ⅱ), andthe Liuhongwan Formation (DS Ⅲ). The carbonate platform and back-platform basin are the basic environ-ment model of the Chartai Group. The syndepositional faults on the oceanward side of the carbonate platformand large-scale slumping in the soft sediments are important marks of facies tracts. The newly establishedZenglongchan uplifting, an epeirogenetic uplifting, plays an important role in the formation of thepalaeogeographic framework of the Chartai Group. The stratigraphic correlation between the Chartai Groupand the Bayan Obo Group is made for the first time by using sequence stratigraphic principle and model estab-lished by P.R. Vail. The Chartai Group, which was deposited on the northern passive continental margin of theNorth China platfom, represents the platform cover.

关键词： Sequence Stratigraphy and Tectonic Environment of the Chartai Group Inner Mongolia

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视觉客体工作记忆中图形特征存储与捆绑时程

心理科学 2007年第5期30卷 1073-1076页

作者：张明狄胜德东北师范大学心理学系长春130024 交通部公路科学研究院北京100088

采用单探测变化检测范式,考察了形状和颜色客体在工作记忆中的表征方式、特征检测类型及初始刺激呈现时间对工作记忆表征的影响。结果表明:(1)视觉客体工作记忆的表征包括两个水平,首先是对客体的特征进行加工存储,其次才是对特征的捆绑... 详细信息

采用单探测变化检测范式,考察了形状和颜色客体在工作记忆中的表征方式、特征检测类型及初始刺激呈现时间对工作记忆表征的影响。结果表明:(1)视觉客体工作记忆的表征包括两个水平,首先是对客体的特征进行加工存储,其次才是对特征的捆绑;(2)不同特征的加工时间不同,颜色的加工完成的较早,记忆效果好,而形状的加工完成的较晚,记忆效果也差,表现出颜色的子系统优势;(3)特征的捆绑不是必需的,只有在任务需要时才进行,并且捆绑的过程符合特征捆绑的双阶段理论。

关键词：视觉客体工作记忆特征捆绑视觉客体工作记忆加工时程

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等离子体射流中陶瓷颗粒的运动与加热

华中科技大学学报（自然科学版） 2006年第11期34卷 29-31页

作者：胡盛德张海鸥王桂兰华中科技大学塑性成形模拟与模具技术国家重点实验室

以格子Boltzmann等离子体射流模型和颗粒运动随机算法为基础,采用气态非平衡热传导方程计算颗粒表面和内部温度变化,对等离子体射流中陶瓷颗粒的热运动进行了数值模拟.模拟结果表明,陶瓷颗粒在等离子体射流中加热时颗粒内部可能出现相... 详细信息

以格子Boltzmann等离子体射流模型和颗粒运动随机算法为基础,采用气态非平衡热传导方程计算颗粒表面和内部温度变化,对等离子体射流中陶瓷颗粒的热运动进行了数值模拟.模拟结果表明,陶瓷颗粒在等离子体射流中加热时颗粒内部可能出现相当大的温差,此温差取决于所经过的等离子体温度,陶瓷颗粒表面温度可以高于也可以低于中心温度.离喷枪出口越近,沿射流横截面颗粒群平均速度和平均温度波动越大,波动较小的高速区滞后于波动较小的高温区.

关键词：等离子体射流陶瓷颗粒温度速度数值模拟