放射性肺纤维化大鼠动物模型的建立及其病变规律

用 60 Coγ射线对二级雌性 Wistar大鼠 (体重 ( 2 2 0± 2 0 ) g) 2 2 3只进行 30 Gy全胸单次照射 ,其中照射野为 4 .5cm× 4 .0 cm,照距为 3m,剂量率为 2 .7Gy/ min。分别于照后 3、7、1 4、2 1、2 8、4 2、56、70、90、1 80、2 70、36 5d共 1 2个时间点进行了取材观察。结果表明 ,肺脏病变初期呈急性变化 ,以后转为亚急性或慢性进行性发展过程 ,可大致分为 2个阶段 4个期。早期即急性炎症期或渗出期 ,中期为增生期 ,这 2期合为疾病的第 1阶段 ,称为放射性肺炎。后期即纤维化期 ,晚期即胶原化期 ,这 2期共同构成本病的第 2个阶段 ,称为进行性间质纤维化阶段     

新疆农村土地市场建设的目标模式

农村土地市场是土地市场不可缺少和不可分割的部分，加快农村土地市场的培育已成为一项十分紧迫的任务，本文阐述了构建新疆农村土地市场的指导思想，基本原则和与目标、步骤，提出了农用地使用权市场目标模式在农用地市场目标模式。     

有限半气化层燃锅炉的综合特性及节能预测

根据有限半气化燃烧的试验研究结果，讨论了有限半所化燃烧过程的主要特性，提出了层燃锅炉有限半气化燃烧节能的预测模型，并根据试验结果对模型加以检验。     

建筑数值风洞的基础研究

数值风洞模拟要想获得理想的计算精度,依赖计算人员的理论基础及其在具体操作中对各种重要因素的选择.针对这个问题,本文采用一个CUBE建筑模型的风洞试验的试验结果作为比较标准,比较了各种不同条件下的建筑数值风洞模拟结果和试验结果,着重分析了网格划分、计算区域、湍流模型和对流项的差分格式等因素对建筑数值风洞数值模拟结果的影响.模拟结果表明:在各种影响因素中,计算区域的影响相对较小,而网格划分、湍流模型的影响相对较大.最后给出如何对上述各种因素作出合理选择的建议.     

氮磷钾肥和种植密度对长白金面瓜产量的影响

本试验采用地次饱和Ｄ－最优设计，通过田间试验测定参数，建立了长白金面瓜的高产优化数学模型，同时解析了各因素对产时的影响效应，提出优化农艺实施方案。     

Final Analysis of the Accuracy and Precision of Methods to Calculate the Sediment Retained by Check Dams

Knowing how much sediment check dams have trapped during their lifespan is essential to estimate their effectiveness or the sediment yields of their basins. Methods to calculate the volume of sediment trapped by check dams play an important role in the understanding of these issues. Several authors have proposed different methods to measure the volume of retained sediment, but their accuracy has, as yet, not been precisely determined and is currently a subject of debate. We compare the most frequently used methods (geometric: prism, pyramid and geometric; topographic: Digital Terrain Models (DTMs), trapezoids and sections methods) to evaluate their accuracy and precision in determining the volume of sediment retained by check dams. Our calculations are based on ten virtual check dams simulated in several gullies of Saldaña (Spain), where we determine their volumetric capacity for trapping sediment (real volume). This was made by means of an intensive topographic survey of these gullies, employing a terrestrial laser scanning system to obtain a high‐resolution digital elevation model (5 × 5 cm, ±2 mm). The results showed that topographic methods provided a very good fit to real volume with a difference of around 8%, being the sections method the most accurate. Geometric methods were less accurate, showing differences of up to 28%. Thus, the results obtained until now by geometric methods should be considered with caution. Although topographic methods were more accurate, they require many field data and much time than the others. So geometric methods can still be useful by correcting their results using our obtained percentage of variation. Knowing the accuracy of the methods before measuring is essential to obtain the most reliable results to analyse the role of check dams in controlling sediment, erosion processes and land degradation. Copyright © 2017 John Wiley & Sons, Ltd.     

云南农业大学产学研合作教育研究

推进农业高校与企业广泛合作，逐步建立高等农业教育与社会生产密切结合的教育机制，是农业高等教育进一步发展的必然趋势。云南是一个农业大省，云南高等农业院校是培养农业高级专门人才的基地。通过对云南农业大学的产学研合作状况进行调查，分析评价云南农业大学产学研合作过程中经验和不足，提出相应措施以推进产学研一体化的新型教育模式。     

山西省农机总动力需求的灰色—马尔柯夫预测模型

灰色—马尔柯夫预测方法能够较好地解决既有趋势性又有较大波动性的数据序列的预测问题 ,且具有计算简便、精度高的特点。本文利用该方法对山西省农机总动力需求进行了预测分析 ,为农业机械化有计划的发展提供了依据。     

对退耕还林工程中种草的探讨

分析种草在退耕还林工程中的重要地位和作用 ,提出退耕种草的草种选择和种植模式 ,并探讨发展草产业的途径和方向