水工结构聚脲防渗涂层的力学性能与寿命预测研究

聚脲防渗涂层材料力学性能的耐久性对保障水工结构工程长久安全运行意义重大,目前缺乏考虑聚脲材料化学构成对防渗涂层使用寿命预测的理论及公式。本研究基于聚脲材料化学键构成、水解老化机理及Arrhenius老化模型,考虑聚脲材料的脲键、氨酯键含量的影响,提出了聚脲防渗涂层的老化寿命预测理论及公式,该理论能够反映不同聚脲材料的氨酯键、脲键含量与水解老化寿命的关系。根据聚脲防渗涂层中氨酯键、脲键含量定义了聚脲涂层力学性能,通过湿热加速老化试验确定了氨酯键水解老化参数,确保了聚脲材料寿命预测公式的可靠性。实现了在不同温湿度运行环境条件下,不同聚脲防渗材料的使用寿命预测及材料设计方法,对水工建筑物聚脲防渗涂层的设计及应用具有指导意义。     

便携式温湿度无线监控系统的设计与实现

利用新一代单片全校准、高集成度、小体积的数字式温湿度传感器SHT71,通过单片机的控制实现对温湿度的采集与显示,再经由无线收发传输采集到的数据与遥控各温湿度调节设备,并结合了便携式与PC机操作。使得此系统具有体积小、适用面广、使用方便等特点。     

基于ZigBee的交变湿热箱温湿度采集监控系统设计

针对目前环境试验室温湿度试验的数据采集和监控采用人工记录和设备本身监控方式存在的不足,设计了一种基于ZigBee的交变湿热箱温湿度采集监控系统.该系统以CC2430射频模块组成无线传感网络,由传感器节点把测量的温湿度参数传递至协调器,再由协调器传至移动终端或经串口上传至PC机,PC端用VS2010制作软件实时记录、显示、存储和处理接收的数据,并发出报警信息,移动终端能与PC端同步设置和查询信息.经测试,该系统传感器布置全面、测量精度高、工作稳定、数据传输可靠,移动终端使用灵活、方便,能满足对交变湿热箱温湿度数据的无线采集和监控.     

氢冷发电机组氢气湿度监控仪

介绍了QJY -A型氢气湿度监控仪的设计原理、仪器功能、性能指标及在发电厂氢冷发电机组氢气绝对湿度在线测量中的应用。     

楼宇母线槽配电干线的温湿度监控系统

根据楼宇母线槽配电干线的特点,设计了一种新型的楼宇母线槽配电干线温湿度监控系统,系统以STC12C5A60S2单片机和ADuC7026处理器为控制核心,通过红外温度传感器和电容式湿度传感器监测楼宇母线槽配电干线的温湿度变化状况,并在液晶显示屏实时显示,若楼宇母线槽配电干线的温湿度严重超限,则在不影响漏电开关原有保护功能上驱动其跳闸。系统对预防安全事故,保证楼字母线槽配电干线安全、可靠运行,具有重要意义。     

高流量呼吸湿化治疗仪的机理分析与数据建模

绝对湿度是高流量呼吸湿化治疗仪的重要控制参数,控制不当会影响治疗效果,建立准确稳态模型是控制绝对湿度的基础。通过对湿化仪的系统结构和工作原理进行研究,建立湿化仪稳态过程的机理模型。此模型具有多元、高阶次和非线性且缺少部分可测参数,难以实现模型的精确辨识。采用多元线性拟合方法,建立以湿化罐出气口温度为控制目标的稳态模型,仪器测试结果表明通过对湿化罐出气口温度进行控制,实现了对湿化罐出气口绝对湿度的间接控制,验证了数据模型的有效性和实用性。     

A new calculation method of water vapour permeability at unsteady states

Abstract

In this article, the calculation methods of water vapour permeability through fabrics are discussed. The applications of the perfect gas in the existing calculations affect their accuracy and even validity, especially at the unsteady state. To solve the problem, a new calculation method is established on the basis of the definition of relative humidity without involving the perfect gas, so that it can be applied to the unsteady state of water vapour transfer. This calculation method has been applied to a new instrument for the measurement of water vapour permeability. Comparisons between the new instrument and the Turl Dish tester have been carried out on four different types of fabrics made of different materials.     

Stability test for amorphous materials in humidity controlled 96-well plates by near-infrared spectroscopy

The purpose of this research is to apply near infrared spectrometry (NIR) with chemoinformetrics to predict the change of crystalline properties of indomethacin (IMC) amorphous under various levels of relative humidity storage conditions. Stability test for amorphous and meta-stable polymorphic forms was performed in humidity controlled the modified 96-well quartz plates containing various kinds of saturated salt solutions (0–100% of relative humidity (RH)) by NIR spectroscopy. Amorphous form was obtained melt product to pour into liquid nitrogen and after then ground. Samples were stored at 25°C in the 6-well plates at various levels of RH. The spectra of the powder samples were measured by the reflectance FT-NIR spectrometer. The second derivative spectra of form α showed specific absorption peaks at 4980, 6036, 7296 and 8616 cm?1 and that of form γ showed those at 5020, 5028, 7344, 7428 and 8436 cm?1. After storage at less than 50% RH, the peak intensities at 5020, 5028, 7344, 7428 and 8436 cm?1 of the amorphous solid increased with increasing of storage time. However, the peak intensity at 4980, 6036 and 7296 cm?1 increased at more than 50% RH. The results suggested that at lower humidity, the IMC amorphous solid transformed into form γ, but it transformed into form α at more than high humidity. It is possible that crystalline stability of the pharmaceutical preparations could be predicted by using humidity controlled 96-well plates and reflectance NIR-chemoinformetric methods.     

配电室温度场与湿度场的建模与仿真分析

考虑到变电站配电室内配电设备对环境温度和湿度有较严苛要求,因此有必要研究配电室内温度和湿度分布规律,有助于提高配电设备可靠性。按照与温度计算有关的能量传递方程和与湿度计算有关的气体扩散方程,由理论计算公式分析可知直接计算涉及多变量的耦合,求解难度大。本文采用有限元分析软件ANSYS对配电室的温度场和湿度场进行仿真计算,首先根据实际的典型配电室建立仿真计算模型,并高精度划分有限元网格。其次根据现场运行情况整定计算仿真需要的计算参数,利用仿真计算模型得到了室内温度场和湿度场的水平面分布情况。通过改变风机流量,分析了风机流量变化对配电柜内部温度的影响效果,总结了配电室内温度场与湿度场的分布规律。     

Jatropha curcas L. (Euphorbiaceae) modulates stomatal traits in response to leaf-to-air vapor pressure deficit

Cultivation of Jatropha curcas in arid and semiarid non-cultivated areas could be a sustainable strategy for stimulating biofuel production without competing with food crops for land and water resources. J. curcas is considered a drought-tolerant species; however, the mechanisms that provide tolerance are unknown. Few efforts have been made to understand the connections between stomatal development and environment conditions. Here, we compared changes in stomatal density (SD) and stomatal index (SI) and their influence on gas exchange in J. curcas. Plants were cultivated in both rainy and dry regions. We describe a distinctive distribution of stomata under the adaxial and abaxial leaf epidermises, where higher SD may have caused the increase in stomatal conductance (g_s) with positive effects on net photosynthetic rate (P_N). However, when rain was excluded, the variation in g_s was strongly related to vapour pressures deficit (VPD), and VPD was strongly related to the P_N. Thus, our results suggest that J. curcas may also contribute mitigating the effect of CO₂ deposition in the atmosphere, given that a remarkable change in SD and other leaf traits was observed in response to seasonal variations. Moreover, multivariate analysis highlights the high sensitivity of J. curcas plants to VPD which in turn induces rapid stomatal closure and consequent reduction of P_N for long periods of time which reflect into a change in the pattern of development resulting in higher SI. These results can help us to understand the relationship between stomatal features and gas exchange in response to environment changes.