微功耗永磁式接触器的研究

永磁式接触器与传统电磁式接触器相比具有:节能,可靠性高,无噪声污染等优点.本文对电磁式接触器和永磁式接触器的静态磁场特性进行了计算分析,计算结果可为永磁式接触器的开发提供了强有力的技术支持,并大大缩短产品的开发周期,降低开发成本.     

AlN薄膜异质结构声波激发特性研究

该文分别开发了两种基于AlN压电材料和原子数分数为10%的Sc掺杂AlN压电材料的薄膜叠层异质谐振器。通过有限元仿真和实验对比分析了器件的频率温度性能和Sc掺杂对谐振器声激励的影响。结果表明,Sc掺杂可能会影响压电薄膜叠层谐振器所激励声波的谐振频率、机电耦合系数和对应的频率温度系数(TCF),且对所激励声波的正反谐振点的TCF影响不同。此研究在传感及滤波器件领域极具应用潜力。     

小口径榴弹自然破片形成过程的数值模拟

采用AUTODYN软件中基于Mott分布生成自然破片的Stochastic材料破坏模型,对30mm小口径榴弹壳体膨胀和自然破碎过程进行了数值模拟,获得了破片初速、飞散角沿轴向曲线分布及破片质量分布,仿真结果与破碎性试验回收破片的统计结果吻合较好。     

给水系统工况动态建模方法

根据给水系统的网络特性 ,并结合我国实际情况 ,分析出管网中的压力预报值与系统的工况模型具有明显的相关性 ,进而提出了充分利用管网现状及历史已知信息的实用动态工况模型 ,并通过了实际城市的验证 ,可直接应用于给水系统的优化调度计算中     

纤维增强轻质混凝土在楼地面保温的应用

介绍了纤维增强轻质混凝土特点及其在楼地面保温隔热上的施工工艺和施工方法,同时阐述了有关注意事项。     

Characteristics of mining gas channel expansion in the remote overlying strata and its control of gas flow

The technology of pressure relief gas drainage is one of the most effective and economic for preventing gas emissions in underground mines. Based on current understanding of strata breakage and fracture development in overlying strata, the current study divides the overlying strata into the following three longitudinal zones in terms of the state of gas flow: a turbulent channel zone, a transitional circulation channel zone and a seepage channel zone. According to the key strata discrimination theory of controlling the overlying strata, the calculation method establishes that the step-type expansion of the mining gas channel corresponds to the advancing distance of working face, and this research also confirms the expanding rule that the mining gas channel in overlying strata follows the advancing distance of mining working face. Based on the geological conditions of Xinjing Coal Mine of Yangquan, this paper researches the expanding rule of mining gas channel as well as the control action of the channel acting on the pressure relief flow under the condition of the remote protective layer, and got the distance using inversion that the step-type expanding of mining gas channel is corresponding to the advancing distance of working face, which verifies the accuracy and feasibility of theoretical calculation method proposed in this study. The research provides the theoretical basis for choosing the technology of pressure relief gas drainage and designing the parameters of construction.     

Characteristic of filamentous fungal diversity and dynamics associated with wheat Qu and the traditional fermentation of Chinese rice wine

Chinese rice wine, a traditional alcoholic beverage, is fermented from steamed rice with a starter culture of wheat Qu which is either inoculated spontaneously with various microorganisms in natural environment or inoculated artificially with certain microorganisms. The diversity of filamentous fungi in wheat Qu and the fermentation mashes of Chinese rice wine was studied by high‐throughput sequencing. The results indicated that filamentous fungi varied in wheat Qu and fermentation periods. Moreover, Aspergillus was the dominant filamentous fungi at genus levels. On that basis, quantitative real‐time PCR was used to quantify some dominant Aspergillus species. It was found that Aspergillus species in wheat Qu were more abundant than that in various fermentation mashes and continually decreased until the end of rice wine fermentation. Furthermore, it was found that different organic acids were produced by microorganisms at different fermentation stages might due to the changes of oxygen and nutrient content.     

Rheology,mechanical, and thermal properties of core–shell silicon-acrylic copolymer emulsion films and its application on surface sizing: role of silane coupling agent

With the assistance of polymerisable maleate surfactant and costabilizer, core–shell emulsions with poly(butyl acrylate) core (PBA) and poly(butyl acrylate–styrene–methacryloxypropyl trimethoxysilane) shell (PSBM) were prepared through seeded emulsion polymerization. Effects of MPTS on rheological, mechanical, and thermal properties were investigated. Simultaneously, the emulsions were utilized as paper surface sizing agents, and corresponding properties were studied. It was found that the emulsion possessed viscoelastistic nature and changed from viscous to elastic with MPTS addition. At the same time, enhanced internal network strength among particles was detected, which was weakened when MPTS concentration was 8%. The tensile strength and thermal stability of copolymer films were therefore increased accordingly. However, decrease in tensile strength, elongation at break and thermal properties was observed with higher MPTS concentration due to weakened interaction among different shells. It was also found that glass transition temperature (T _g) did not influence greatly by MPTS, and two phases corresponding to core and shell copolymer were observed with low degree of microphase separation. Furthermore, the interaction between polymer and fiber was improved, resulting in improved sizing degree, ring crush strength, surface strength, and folding strength. While the surface strength and folding endurance decreased due to the increase of brittleness with higher crosslinking degree.     

水剂法制油和饲用菜籽浓缩蛋白中试

本工艺有效地脱除了菜籽中的硫葡萄糖甙、单宁、芥子碱、水苏糖、棉子糖和皂甙等抗营养因子,防止了硫葡萄糖甙降解成异硫氰酸盐、硫氰酸盐、噁唑烷硫酮和腈类毒性物质对油脂、蛋白质和环境的污染,同时还有效地防止了菜籽蛋白质热劣变。因此,制得的菜籽油含硫量低,有利于加工开发利用,生产的饲用菜籽浓缩蛋白,通过养鸡试验,不仅可以代替豆饼,蚕蛹,而且也可以完全代替鸡日粮中的进口鱼粉。     

速溶高蛋白花生晶的研制

本文根据营养学原理及水剂法花生加工工艺研制优质营养食品。利用花生、蔗糖等原料生产速溶高蛋白花生晶,这是一种优质、新型的植物蛋白饮料。本文详细地介绍了速溶高蛋白花生晶研制的理论依据,生产配方及方法。