推行集中供热设备标准化、系统化管理的探讨

针对集中供热设备标准化、系统化管理,提出了建议与探讨,能更好的满足节能减排和优化城市环境的要求。     

连云港口岸国际航行船舶截获植物有害生物情况分析与建议

为强化对国际航行船舶的检疫监管,降低植物有害生物传入风险,本文对"十二五"期间连云港口岸国际航行船舶截获植物有害生物的情况进行了统计,掌握了截获有害生物的种类,分析了影响截获的主要因素,并提出相应的检疫对策。     

论信息时代网络语言中的外来语

随着信息时代网络交流的日益普及,网络与语言结合,形成了一种全新的语言模式—网络语言。网络语言中一个突出的现象是大量外来语杂糅其中。通过分析网络语言中外来语的表现形式,探讨网络语言中外来语流行的原因,并提出如何正确看待这一现象。     

Characterizing long-term forest disturbance history and its drivers in the Ning-Zhen Mountains,Jiangsu Province of eastern China using yearly Landsat observations (1987–2011)

Forest losses or gains have long been recognized as critical processes modulating the carbon flux between the biosphere and the atmosphere. Timely, accurate and spatially explicit information on forest disturbance and recovery history is required for assessing the effectiveness of existing forest management. The major objectives of our research focused on testing the mapping efficacy of the vegetation change tracker (VCT) model over a forested area in China. We used a new version of VCT algorithm built upon the Landsat time series stacks (LTSS). The LTSS consisted of yearly image acquisitions to map forest disturbance history from 1987 to 2011 over the Ning-Zhen Mountains, Jiangsu Province of east China. The LTSS consisted of TM and ETM+ scenes with different projections due to distinct data sources (Beijing remote sensing ground station and the USGS EROS Center). The validation results of the disturbance year maps showed that most spatial agreement measures ranged from 70 to 86 %, comparable with the VCT accuracies reported for many places in USA. Very low accuracies were identified in 1995 (38.3 %) and 1992 (56.2 %) in the current analysis. These resulted from the insensitivity of the VCT algorithm to detect low intensity disturbances and also from the mis-registration errors of the image pairs. Major forest disturbance types existing in our study area were identified as agricultural expansion (39.8 %), urbanization (24.9 %), forest management practice (19.3 %), and mining (12.8 %). In general, there was a gradual decreasing trend in forest cover throughout this region, caused principally by China’s economic, demographic, environmental and political policies and decisions, as well as some weather events. While VCT has largely been used to assess long term changes and trends in the USA, it has great potential for assessing landscape level change elsewhere throughout the world.     

超干种子老化方法比较研究

本试验种用谷子、绿豆，经４０℃及４５℃，湿度ＲＨ＝９５％－１００％老化６天及５天。然后测各含水量的５项活力指标。经生物统计表明：谷子４０℃，４５℃二处理间差异显著，且４０℃高温老化６天时间，在不同含水量的组合上，除含水量０．８５％外，其余二因子组合均优于４５℃老化６天的不同含水量处理，且有０．０１显著差异。绿豆老化温度亦以４０℃较好，种子含水量老化结合谷子和绿豆均以５．８％处理效果最好，二种作物经     

羊沙门氏菌病流行与防治

羊沙门氏菌病是是由多种致病性沙门氏菌感染引发的一种急性传染性疾病,不同年龄品种的羊都可以受到病原侵染,其中对羔羊造成的危害最为严重,尤其是断奶不久后的羔羊感染沙门氏菌后,表现的临床症状最为明显,致死率最高。临床上由于致病性沙门氏菌的种类较多,侵染途径多样,一旦受到病原侵染,将很难清理,会造成羊群反复流行,带来的经济损失不可估量。该文主要探讨羊沙门氏菌病的流行特点与防治措施。     

前桥摆转转向式四驱底盘结构形状指数的优化

前桥摆转转向式四驱底盘可直接转入下一畦作业,提高了小地块工作行程率,在地头宽度小于等于1个作业宽度时,更有利于机耕过程中的转向操作。为此,通过ADAMS软件仿真,以最小地头宽度为目标对底盘结构参数进行了优化。仿真结果表明,底盘在作业过程中从一畦进入地头直接转入相邻的下一畦时,后内侧轮基本上不吃入上一畦,最小地头宽度与长宽比成反比。在底盘转向时行走轮不干涉后悬挂农具的前提下,底盘最小的理论长宽比应为0.5:1。但由于底盘长宽比受行走轮直径、轮宽及重心的影响,底盘的合理长宽比值范围需趋近于理论长宽比。当机具作业宽幅大于等于机具轮宽时,可直接做倒U形转向;否则采用"4"和歪梨形组合掉头转向,实现地头宽度等于1个作业幅宽的转向。     

闭式脱粒滚筒的静动态性能分析

针对联合收割机中闭式脱粒滚筒有可能在外载荷作用下会发生较大变形和在外激励作用下发生共振的问题,采用SolidWorks软件对闭式脱粒滚筒进行了三维建模,以*.x_t格式导入Ansys Workbench建立有限元模型,然后对闭式脱粒滚筒进行静动态性能分析(即静态分析和模态分析)。静态分析结果表明,闭式脱粒滚筒的刚度和强度足够,变形均在设计允许范围之内;模态分析得到的闭式脱粒滚筒前6阶固有频率和振型结果表明,在规定的工况范围内,闭式脱粒滚筒在外激励作用下不会产生共振。研究结果为后续样机的设计和改进提供了理论依据。     

授粉技术和单株留瓜数对鄂丝瓜1号制种效果的影响

以鄂丝瓜1号的父、母本为试材,以父本当天上午开放的雄花为花粉来源,研究了授粉时间、花粉供给量和单株留瓜数对种子产量和质量的影响。试验结果表明,母本雌花开放的当天上午和开花前1 d上午均可作为鄂丝瓜1号制种的适宜授粉时间;以1朵雄花为3朵雌花进行授粉为鄂丝瓜1号制种的首选花粉供给量;鄂丝瓜1号制种中,1株母本可以留5~6个种瓜。     

石墨炉原子吸收光谱法测定新资源食品中的硒含量

建立一种简便、快速、准确的食品中硒的测定方法;检测新资源食品芝麻叶、野生四叶参、野生菜葛根、野生葛花及桑蚕蛹中的硒含量。用1mg·mL-1硝酸镍为基体改进剂,加入体积分数为0.1%TritonX-100和0.5%硝酸(1∶1),以改善样液的表面张力。用HITACHIZ-5000型石墨炉原子吸收光谱仪及全自动进样方法进行硒含量测定。石墨炉采用光控升温方式,硒的灰化温度按程序升温方式进行,程序升温分为干燥、灰化、原子化和净化。该方法的测定限为18.6μg/L,精密度为3.26%￣9.29%(RSD),加标回收率为92.1%￣108.8%。该方法具有测定简便、快速和准确等特点,可作为食品中硒含量测定的良好方法。