降雨入渗路基湿度场演变规律

为研究受地下水位高度差异的影响降雨入渗路基湿度场的分布与变化状态,基于饱和-非饱和土渗流理论,构建了5种具备不同初始地下水位的路基数值试验模型.通过分析两种降雨强度情况下的试验结果,总结了湿度场变化的主要规律,并阐述其根本机理.结果表明:降雨雨强越大,地下水受到扰动抬升越显著,路基层位越低,其湿度和扰动区扩距受地下水影响越显著;随着初始水位降低,路堤湿度极差的增幅呈二次曲线增大并至稳定值,扰动区水平扩距呈二次曲线减小并至稳定值;工况一定,则对应存在一个平衡水位线,当初始水位在其之下时,对路基湿度演变影响甚微,反之,随着初始水位的增高,路基湿度增幅呈对数递增.处于平衡水位之上时,初始地下水位高度对降雨入渗路基引发湿度场的分布与变化状态影响显著.     

Preparation and properties of a long-life cementbased mortar used on metal oilcans

Organic-based materials are often used as the coating of metal oilcans. But they need to be sprayed several times in the whole life of oilcans because of the short-life of organic components. To overcome this problem, a type of long-life flexible cement-based anti-corrosion material used on the surface of metal oilcans was developed according to the principle that the steel reinforced concrete can remain the same life with buildings. The materials with different formulas composed of acrylic ~nulsion, cement and other additives were prepared. Because the ratios of polymer to cement played the decisive role in the adhesion and anti-corrosion characteristics, their effects on the physical performances were investigated by comparing the mechanical properties, anti-corrosion and anti-aging properties. The relationship between microstructure and macroscopic properties was also discussed.     

Dynamic buffering performance of the honeycomb paperboard filled with polyurethane

A new kind of composite buffering material was made by filling the voids of honeycomb paperboard with polyurethane. Drop tests were performed to evaluate the dynamic energy absorption capacity of the material. Based on the tests results, we analyzed the mechanical behaviors of the material under different conditions and obtained the inherent influencing laws of some factors on the material＇s dynamic buffering performance. It was shown that the dynamic buffering performance varied directly with impact velocity, and inversely with the void diameter, thickness and buffeting area of the composite material.     

Novel predictive model for metallic structure corrosion status in presence of stray current in DC mass transit systems简

The novel method to analyze metallic structure corrosion status was proposed in the presence of stray current in DC mass transit systems. Firstly, the characteristic parameter and the influence parameters for the corrosion status were determined. Secondly, an experimental system was established for simulating the corrosion process within the stray current interference. Then, a predictive model for the corrosion status was built, using a support vector machine （SVM） method and experimental data. The data were divided into two sets, including training set and testing set. The training set was used to generate the SVM model and the testing set was used to evaluate the predictive performance of the SVM model. The results show that the relationship between the characteristic parameter and the influence parameters is nonlinear and the SVM model is suitable for predicting the corrosion status.     

胜利褐煤二硫化碳-丙酮萃取物的超临界醇解物的GC/MS分析

胜利褐煤经CS2-丙酮混合溶剂(V/V=1 1)萃取获得萃取物EM,EM在300℃的甲醇中热溶2 h获得热溶物ET.对EM和ET进行了气相色谱/质谱联用(GC/MS)分析,在EM中有43种GC/MS可检测组分,而在ET中检测到了132种有机化合物,其中包括32种在EM中未检测到的甲酯类化合物(MAs)和16种酚类化合物.分析了MAs和酚类化合物的形成机理,得出了胜利褐煤CS2-丙酮可溶大分子化合物中可能存在的4种结构单元.本文提供了一种研究煤中可溶大分子化合物的有效方法,弥补了GC/MS在检测大分子化合物时的不足.     

高职院校教师服务企业能力的调查与研究

为了进一步提高教师服务企业的能力,对12个具有代表性的高职院校教师服务企业能力的情况进行调查研究,结果表明:高职院校存在人力资源供给不足、设施设备功能单一、技术资源市场脱节、教师服务时间投入有限、服务对象参与不够等问题.根据对高职院校及企业的调查与现状分析,得出了提升高职院校教师服务企业能力的相关对策,即创新体制机制、激发服务动力、沟通双边信息、挖掘服务潜力、优化教学资源、增强服务活力.     

综合物探技术在煤矿巷道底板富水区勘探中的应用效果分析

徐州市西北地区山西组7;煤开采受底板L4灰岩影响,易发生底板突水事故,为了迅速达到疏水释压效果,需综合利用超高密度电法和矿井瞬变电磁法物探手段对某工作面巷道底板进行探测,圈定相对富水区,探测结果表明,超高密度电法在垂向上较好解释了巷道底板下L4灰岩界面起伏形态,瞬变电磁法在横向上较好解释了L4灰岩富水区,成果经排水孔验证,效果理想,达到探测目的.     

共轭亚油酸强化型乳制品的稳定性研究

通过牛乳液中添加共轭亚油酸（CLA）,分析杀菌温度、均质压力、乳化剂类型、CLA添加量对牛乳稳定性的影响.实验结果表明：脱脂乳中添加0.17%的CLA稳定性较好,口感纯正;当灭菌温度超过100℃时,CLA含量明显降低;以单苷酯、三聚苷酯和蔗糖酯的混合乳化剂,按1∶1∶2混合的乳液稳定性好;35MPa以上的均质压力下,乳液中的脂肪球细小,分布均匀,口感细腻。     

轴向运动屈曲梁非线性振动研究

为解决屈曲梁在不同的激励条件下产生共振问题,基于哈密顿原理建立屈曲梁的振动模型以及非线性偏微分振动方程和边界条件,通过数值模拟分析了屈曲梁在相平面的动态特性.采用多模态伽辽金离散法预测静态弯曲参数,通过局部分析获得某一个弯曲附近处的非线性近似响应,并得出有效的非线性表达式和频率响应曲线.