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排序方式: 共有108条查询结果,搜索用时 46 毫秒
1.
通风幕墙技术及其研究进展   总被引:1,自引:0,他引:1  
本文介绍了新型玻璃幕墙——通风幕墙的基本概念、典型类别、工作原理和研究进展。着重阐述通风幕墙在风压和热压作用下强化自然通风的基本原理。叙述了通风幕墙的节能特性和国内外采用Network模拟法、CFD模拟法及能耗模拟软件对其做的研究工作。以求为进一步的研究及为这种生态建筑的设计、建设、管理、发展提供一个基本依据。  相似文献   
2.
夏热地区热通道玻璃幕墙的热工数学模型   总被引:1,自引:2,他引:1  
本文介绍了热通道玻璃幕墙的简单数学模型。模型的物理概念和Trombe墙相似。该幕墙由外侧单层和内层中空玻璃组成热通道。列出稳态状态下热通道的热平衡方程,通过线性矩阵求解了两个玻璃和通道内空气的半均温度,并使用热阻网络表达在太阳辐射条件下,热通道的传热过程。计算机模拟表明,夏热地区热通道幕墙内层中空玻璃的外表面温度较传统幕墙的表面温度有明显降低,由太阳透射引起的房间得热也有较大减少。  相似文献   
3.
An artificial olfactory, which is called an electronic nose system (e-nose), is studied for realizing new human–machine interface. The system consists of sensor unit and a signal processing unit. There are some types of sensors for the sensor unit, metal oxide semiconductor gas sensors (MOGS) and quartz crystal microbalance gas sensors are useful in our study. Our system in this paper has MOGS. Many of MOGS utilize an effect of an oxidation–reduction reaction on the surface of the sensors. One of the features of the sensor, the character of the sensor is changed by temperature of the sensors. In this paper, we build a extend output sensor unit using this feature, and show experimental result of classification applying multilayer perceptron. In the experiment, we choose soy sauce as classification targets because we are considering applying the system for management of cooked foods.  相似文献   
4.
在水资源和环境问题日益突出的今天,在工农业生产和人民生活中广泛应用的冷却设备——冷却塔对于节省水资源和保护环境发挥了重要的作用.从冷却塔塔体结构材料的角度对不同塔体结构的特点进行了阐述和分析,并对其进行了比较,以供在冷却塔选型、设计时参考.  相似文献   
5.
The free nucleotides of semi-aerobically and aerobically cultured baker's yeast in different industrial stages have been investigated under different conditions: during growth and at rest, and during respiration and fermentation of different substrates. The amounts of protein and nucleic acids diminish progressively during industrial propagation, while the amount of free nucleotides falls only during the last stage of propagation. In yeasts cultured under different conditions of aeration and nutrient addition, the nucleotide spectra were rather similar, but the proportions of the free nucleotides change considerably when the yeast passes from the resting state to growth or metabolism. On transfer from respiration to fermentation the nucleotide spectrum remained practically unchanged. However, a small addition of ethanol to a respiring yeast suspension caused clear alterations in the spectrum, the most obvious being the reduced amount of nucleotides with energy-rich phosphate bonds.  相似文献   
6.
The classical plate method for discriminating between viable and nonviable yeast cells in stored baker's yeast was compared with dead cell staining techniques using methylene blue and three fluorochrome stains. The increase of dead yeast cells during storage of baker's yeast for up to 16 days at 5°C, 20°C and 35°C was determined. During prolonged storage, especially at 35°C, the death rate increased rapidly and the yeast cake began to soften because of autolysis. In these conditions the choice of method for determining the proportion of dead cells proved to be of great importance. Useful results for yeast stored for some time at 35°C could be obtained only by the fluorochrome technique using primuline, acridine orange or acriflavine as fluorochromes.  相似文献   
7.
The contents of cytochromes in yeast were determined quantitatively from the absorption spectra, using a solid cell paste of intact yeast. During the industrial production of baker's yeast, the contents of the cytochromes, particularly of cytochrome aa3 at successive stages, increased gradually with increasing aeration. In semi-aerobically grown baker's yeast, the contents of cytochromes aa3, b and c were 0·9, 2·9 and 2·9 × 10?5 moles/litre of fresh yeast (total amount 6·7 × 10?5 moles/litre), while in vigorously aerated commercial baker's yeast the respective values were 2·3, 4·8 and 5·2 × 10?5 moles/litre (total amount 12·3 × 10?5 moles/litre). In brewer's yeasts separated after the brewing process, the contents of cytochromes were markedly lower than in baker's yeast grown with limited aeration, whereas in top-fermenting yeast the total cytochrome content, aa3 + b + c, was in some samples markedly higher, 7·1 × 10?5 moles/litre, than in bottom-fermenting brewer's yeast, 2·4 × 10?5 moles/litre. When brewer's bottom yeast was grown on a laboratory scale under increasing aeration, a maximum appeared in the cytochrome contents when aeration was moderate, and increased aeration inhibited the formation of cytochromes. The cytochrome contents in brewer's bottom yeast may exceed the amounts found in commercial baker's yeast. In addition to aeration, the type of metabolism influences the amounts of cytochromes in yeast.  相似文献   
8.
空调系统中含热回收设备的节能分析   总被引:5,自引:1,他引:4  
介绍了全热回收设备的结构和工作原理,分析了在不同湿球温度下全热回收设备的节能情况,并用温度频率法分析了一个实际的新风系统全年情况下采用全热回收设备的新风能耗的情况。  相似文献   
9.
10.
基于GPS和GSM的车辆监控调度系统   总被引:3,自引:0,他引:3  
为了提高车辆行驶的安全性,物流配置的快捷性,车辆调度的实时性,设计了一种基于GPS和GSM网络技术的车辆防盗监控调度系统.采用短消息的方式将车辆的位置信息发送到监控中心,监控中心可在电子地图上实时查看移动车辆的具体位置,实现了对多车系统的实时监控和合理调度,解决了常规报警系统的空间局限性.  相似文献   
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