Neural networks modeling signal responses and taxol production of cultured Taxus chinensis cells induced by bio-elicitor

Quantitatively describing the signal transduction process is important for understanding the mechanism of signal regulation in cells, and thus, poses both a challenge and an opportunity for chemical and biochemical engineers. An artificial neural network (ANN), in which we took the signal molecules as neural nodes, was constructed to simulate the generation of active oxygen species (AOS) in Taxus chinensis cells induced by a bio-elicitor. The relative contents of AOS in cells predicted by the ANN model agreed well with the experimental data and three notable stages of AOS increase were observed from the 3D figure of AOS generation. The robustness of AOS trajectories indicated that signal regulation in vivo was an integral feedback control model that ensured the adaptation of Taxus chinensis to environmental stress. The artificial neural network was able to predict taxol production as well as determine the optimal concentration of oligosaccharides needed for it.     

软土路基沉降计算新方法及应用研究

介绍了一种动静结合的软土路基沉降计算新方法,并将该方法应用到动力固结路基处理工程实践中.对软土路基沉降进行了计算,通过将沉降计算值与实测值进行比较,验证计算方法的可行性.计算结果显示,路基断面总沉降量计算值为669.6 mm,实测值为675 mm,两者比较相近,说明该沉降计算方法是可行的.     

工程结构动态特性智能优化设计研究

本文针对在传统结构优化设计中，优化过程复杂和费时的问题，采用神经网络的智能算法对结构进行动态优化设计，并给出了具体的设计方法。以门座起重机筒型支柱结构为例，应用此方法对其进行了动态优化设计计算，从而证明了该算法的有效性。     

Alkylated ureas: mineralization and evaluation as N sources

An incubation experiment was conducted for 11 weeks to study the mineralization of ten alkylated ureas and urea in soil. Six of the alkylated ureas viz. methylurea(MU), 1,3-dimethylurea(1,3DMU), 1,1-dimethylurea(1,1DMU), ethylurea(EU), 1,3-diethylurea(1,3DEU) and butylurea(BU) and urea mineralized during the experiment. Urea mineralized immediately, while alkylated ureas mineralized after an incubation period ranging from less than a week to four weeks (delay period of mineralization). The delay period increased in the following sequence MU < 1,3DMU < EU < BU < 1,1DMU < 1,3DEU, but after the delay period was over the compounds mineralized almost as rapidly as urea. The delay period varied according to the number of carbon atoms in the alkyl group and their position with respect to each other on the molecule. It appeared to be specific for each compound and was apparently not influenced by the presence of urea or other alkylated ureas. This character can be used to develop mixture of various alkylated ureas to obtain N mineralization at the desired time. Rapid evolution of CO₂ and N₂O was observed during the mineralization of urea as well as alkylated ureas. Increase in soil pH was also observed during this period. The simultaneous ocurrence of these events suggested the formation of urea as an intermediate during the mieralization of alkylated ureas. None of the alkylated ureas showed adverse affect on emergence of wheat seedlings and except DEU and BU at high concentration no other alkylated urea showed any adverse effect on initial growth of wheat seedlings.     

动态信号分析系统的进展及应用

本文综述了动态信号分析仪器与系统的发展,并综合介绍了双通道动态信号分析仪的构成、性能与指标,以及由动态测量、数据采集、信号处理等硬件与相应软件组成的多通道动态信号分析系统的进展.     

奇异值分解对非定常约束多体系统的动力学分析

通过对约束方程的雅可比矩阵进行奇异值分解，定义组合坐标，从拉格朗日第一类方程出发，建立了非定常约束多体系统的纯微分方程，给出了动力学数值分析的过程，最后举了一个算例。     

动载荷下应力强度因子的边界元计算

用Ｎａｒｄｉｎｉ－Ｂｒｅｂｂｉａ边界元法计算了动载荷下的应力强度因子，与解析解及有限元解相比较，效果较好。最后对计算结果进行了分析讨论。     

SiH4＋CH4激光等离子体动力学时空特性

采用时间，空间分辨的等离子体光辐射诊断技术，研究了脉冲ＴＥＡＣＯ２激光诱发ＳｉＨ４＋ＣＨ４击穿产生的等离子体膨胀过程，得到不同空间位置，不同实验条件下等离子体发光的时间特性，证明了ＳｉＨ４＋ＣＨ４气体击穿产生爆燃波而后诱发激波是等离子体中基本宏观动力学过程，并在实验上分析了激波对等离体内化学反应的影响，为激光等离子体合成ＳｉＣ粉末微观反应动力学过程的研究提供了参考数据。     

动态交联热塑性弹性体增韧聚丙烯合金

用动态交联方法制备聚烯烃热塑性弹性体（ＴＰＯ）增韧聚丙烯，制备了具有低温冲击性能良好、综合力学性能比较均衡的聚丙烯合金。同时，研究了ＴＰＯ组成、工艺及基体组成与ＴＰＯ增韧聚丙烯共混物力学性能的关系。并通过差热扫描量热计和扫描电镜考察了共混物的形态结构。     

气体动压轴承动态参数测定原理

将气体动压轴压简化为转化气膜系统后，针对其动力特点，给出气膜在微幅振动下动压轴承的实用数学模型和测定动态参数的方法，并进行了测量误差的修正。