轮作条件下秸秆施用方式对农田水分及作物产量的影响

通过小区试验,研究了粉碎、氨化秸秆以及与无机土壤改良剂（硫酸钙）混合配施措施对土壤水分及作物产量的影响。结果表明,氨化秸秆利于提高土壤对降水的保蓄能力,显著增加0~100 cm土层土壤蓄水量。在夏玉米-冬小麦轮作中,氨化秸秆提高土壤蓄水能力主要反映在夏玉米苗期和冬小麦抽穗期。粉碎秸秆氨化与硫酸钙处理的夏玉米、冬小麦水分利用效率分别较粉碎秸秆覆盖提高了4.97%、30.32%,效果显著。氨化秸秆施入土壤的措施较未氨化秸秆覆盖还田的措施夏玉米、冬小麦产量分别提高4.56%~10.00%和6.65%~11.12%。     

梳棉内层杂质高光谱图像检测

以梳棉内部深度1 ～6 mm处的多种杂质为研究对象,研究了高光谱成像技术检测效果和可行性.在波长460～900 nm范围内,提取高光谱图像中杂质和棉花的像素光谱.采用二次判别分析分类像素,构造分割二值图像,使用面积过滤器和形态学组合方法剔除二值图像中的噪声点和伪目标,统计杂质检测效果.结果表明可以检测棉网内一定深度的普通杂质(植物性杂质)、彩色丙纶丝、有色线和有色布块,能够检测部分黑色毛发和灰色丙纶丝.其中,普通杂质的检测效果最佳,正确检测率超过80％.     

聚乙二醇胁迫下甘蔗根系蛋白质差异表达图谱分析

以甘蔗品种ROC22为材料,采用含100 g/L聚乙二醇（PEG）6000的Hoagland营养液模拟干旱胁迫处理,SDS-PAGE电泳技术分析干旱胁迫对甘蔗幼苗根系蛋白质的影响。结果表明:与对照相比,24 h胁迫过程中稳定存在的新增蛋白条带为44.5 ku,可能是应答干旱胁迫的主要新增调节蛋白;57.1和29.0 ku 蛋白条带在24 h处理期间相对表达量变化活跃,胁迫初期57.1 ku蛋白条带显著增加,29.0 ku蛋白条带显著下降,胁迫过程中出现起伏变化;而62.7、40.4与48.2 ku蛋白条带在PEG胁迫早期相当长时间保持稳定,后期才出现显著增加与下降; PEG胁迫14 h处理蛋白质条带变化最活跃,新增蛋白分子质量为44.5 ku;消失蛋白分子质量为25.5、18.9 ku;而分子质量为81.8、48.2、38.0、29.0 ku的蛋白条带表达量下降。甘蔗根系蛋白质在响应PEG胁迫的基因表达调控中扮演重要角色,其变化可能与甘蔗PEG胁迫密切相关。     

双向SLA公平调度算法及其在EPON中的应用

研究了开放接入网络中带宽分配的公平性问题.将最大〖CD*2〗最小公平算法应用到双向SLA带宽调度算法中,给出了一种基于EPON的易于实现的双向SLA公平带宽调度算法.以用户SLA为首要SLA,以业务提供商的SLA为次要SLA,通过带宽分配和调整,实现了双向公平的带宽分配.仿真实验表明,双向SLA算法实现了业务提供商和用户的公平性需求,具有合理性和可用性.     

Frost resistance and chloride ion diffusion of silica fume concrete in a marine environment

The properties of silica fume concrete in natural sea water are studied, with special focus on the relationship between the freeze thaw durability and chloride ion diffusion coefficients. The influence of various factors on concrete resistance to frost and chloride diffusion is studied, including the water cement ratio, equivalent silica fume dosage substitution for cement, and the amount of air entraining agent and compared with that of ordinary concrete. The results show that adding silica fume cannot improve the frost resistance of concrete but it increases resistance to chloride diffusion. Both the frost resistance and chloride diffusion properties can be improved simultaneously when silica fume is used with an air entraining agent. A silica fume content of approximately 10% is the optimum value for the composite resistance to frost and chloride diffusion. A new assessment method (R value method) is proposed to evaluate the composite properties of frost resistance and chloride diffusion of marine concrete.     

体育专业大学生照镜子行为与身体自尊的相关研究*

为了探讨“照镜子”行为与身体自尊的关系,采用问卷调查法、访谈法、数理统计法等对303名体育专业大学生的“照镜子”行为和身体自尊状况进行测查,结果发现：体育专业大学生照镜子的态度良好;每天照镜子的次数多集中在3~5次,男生显著高于女生;体育专业大学生的身体自尊水平中等偏上,且存在较大的个体差异;不同照镜子态度、频数以及满意度在身体自尊方面存在一定的差异。     

Influence study of constructed rapid infiltration system constructedby purple soil on sewage Nitrogen removal performance

The nitrogen removal performance of a constructed rapid infiltration system (CRI) constructed using the common purple soil and sand from the Three Gorges Reservoir Region in the P.R. China was studied. In order to optimize the construction and the nitrogen removal performance of the CRI, three 1.5 m high columns were examined using mixed media with soil/sand ratios of 2∶1, 3∶1 and 4∶1, respectively. Four soil columns with heights of 0.3, 0.6, 1.0,1.5 meters subsequently were tested using media ratio of 3∶1. It is shown that the CRI constructed by the medium of sand/soil ratio being 4∶1 possesses better removal performance for the removal of NH3 N, NO3 N and TN. The removal rates for NH3 N and TN are 71.7% and 48.8% respectively, close to the nitrogen removal performance of unmixed purple soil. Hence the 4∶1 medium of sand/soil ratio is appropriate. It is also shown that, when considering the functional area of CRI treating the sewage, the upper 0.6 m of CRI is the main area that removes COD and NH3 N, whilst 0.6 m~1.0 m is the main area that removes TN. Increasing the soil layer thickness does not ensure better nitrogen removal performance. The 1.0 m soil layer thickness of a CRI system is appropriate for treating sewage in the Three Gorges Reservoir Region.     

Design of a control system for auto loading and unloading of compressed natural gas bottles

The concept of centralized filling and separate bottle displacement was introduced to reduce the inconvenience of filling compressed natural gas(CNG) vehicles. By taking a programmable logic controller (PLC) as the smart control unit and stepper motors as drive units, a mobile three dimensional table was designed as a working platform. The stepper motor control algorithm was studied, and the system model for the CNG vehicles automatic loading and unloading was constructed. A new automatic loading and unloading system for CNG vehicle bottles was developed. Theoretical analysis and experimental results show that the system can complete the automatic loading and unloading task in 1 or 2 minutes, thereby improving CNG vehicle filling efficiency.     

车架弹性对重型载货汽车行驶平顺性的影响

以某重型载货汽车为研究对象,利用有限元方法及虚拟样机技术建立整车多刚体模型和考虑车架弹性的整车刚弹耦合模型。在B级路面上满载工况下对整车行驶平顺性进行仿真分析,研究车架柔性对驾驶员座椅地板加权振动加速度均方根值、悬架动挠度和车轮动载荷3个平顺性评价指标的影响,同时进行整车操纵稳定性的稳态回转性能仿真分析,讨论车架弹性对整车稳态回转性能的影响,并进行相应的实车试验验证。结果表明,考虑车架弹性后整车平顺性的仿真分析结果比把车架视为刚体更接近试验结果;车架刚性越大,其低阶固有振动频率越高,驾驶员座椅地板加权振动加速度均方根值、悬架动挠度和车轮动载荷越小,整车行驶平顺性变好;同时适当增加车架的刚性,会使整车的稳态回转性能得到改善。设计车架时,适当增加车架刚度、提高车架低阶固有振动频率,可改善重型载货汽车整车行驶平顺性。     

超声波处理对糙米吸水特性的影响

糙米超声波处理后,在不同温度浸泡过程中对糙米含水率的变化进行了比较分析,利用Peleg方程对糙米在60℃以下浸泡过程中吸水特性进行模拟,同时对糙米在60℃以上的水分吸收过程进行了考察分析。试验结果表明：超声波处理提高了糙米对水分的吸收速率;利用Peleg方程能够很好地模拟糙米在60℃以下的水分吸收过程,回归系数r2≥0.996,水分扩散的测量值与预测值没有显著差异（R＜5%）。