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排序方式: 共有41条查询结果,搜索用时 15 毫秒
1.
Dielectric barrier discharge (DBD) can produce homogenous discharge in normal temperature and atomsphere with low energy consumption, so it has broad development prospects in industrial applications. An experimental study is carried out to optimize the needles arrangement and supply parameters aiming at the multineedle-to-cylinder reactor with orthogonal design in combination with Lissajous figures. As it is konwn, the process of discharge is also the process of charge transfer; hence, the more charges are transported, the higher reaction efficiency in plasma is. The orthogonal design is established with transported charges as the goal factor, and supply voltage, supply frequency, needles length(NL), interneedle rotation angles(INRA) as factors. Variance analysis results show that the largest influence factor is supply voltage, followed by supply frequency; the electrode configuration of NL=(3.5+2) mm and INRA=45° matched with f=21 kHz makes transported charges per cycle biggest. The orthogonal experiment results are verified by further experiments, which is significant to improve the DBD plasma reaction efficiency.  相似文献   
2.
Thermal Performance and Energy Analysis of Green Roof   总被引:2,自引:0,他引:2  
Energy consumption and thermal parameters of green roof and bare roof were measured in the air conditioned and nature indoor environment in summer.It was found that the heat flow of green roof was reduced about 70%, and additional equivalent thermal resistance of green roof was about 1.0 m2·K/W in the air conditioned,cooling efficiency of green roof was about 111% in the nature condition.  相似文献   
3.
A novel hydrolysis acidification reactor in concentric structure was designed and developed, which could improve the biodegradability of wastewater effectively by the enhancement of the mixture performance due to the stirring and reflux. The pilot scale study showed that the COD removal rate could reach over 46% and 36% respectively treating the two different kinds of refractory wastewater. Moreover, the reactor could cut down the operational cost through the variation of the operation mode. According to the comparison with other hydrolysis acidification reactors, the result showed that a 6 percentage point of improvement in COD removal could be reached to the novel hydrolysis acidification reactor.  相似文献   
4.
Dynamic characteristic analysis of an all terrain vehicle body   总被引:1,自引:0,他引:1  
The body is a key part of all terrain vehicles (ATV). Its dynamic characteristics greatly effect the vibration of the ATV assembly. Simulation and experimental methods are combined to analyze ATV body vibration characteristics. A computer aided design(CAD) model is built using UG4.0. A finite element method(FEM) model of an ATV body and a body with an engine are created using Hypermesh. The FEM model is imported to Msc.Nastran to calculate the free mode. The simulation model is verified by the experimental modal result. The results indicate that after the frame with engine, the first bending mode increases due to the engine increasing the body stiffness, while the first torsion mode decreases due to the engine mass. The effects on the dynamic response of the road and engine excitation are analyzed respectively. Vibration characteristic improvement methods and suggestions regarding the body are provided.  相似文献   
5.
This article introduces that there are good basic conditions and big development space for the industrialized housing development in Chongqing Municipality-the biggest municipality in the country.And it introduces the capabilities of horizontal transportation by land or sea and vertical lifting in Chongqing. And it puts forward that is more economical, reliable and safer than which has the advantages of best weight lifting capacity, service radium. Lifting height and smallest site occupation and the assemble of bigger components even the whole industrialised house.  相似文献   
6.
By analyzing the pressure distribution between gears and sealing blocks in compound gear pump with three idlers,the resultant hydraulic forces acting on seal blocks are obtained.The conclusion is the unbalanced resultant hydraulic forces are relatively small in magnitude.In the pump,the inner sealing edges are long and so it s Sealing effect is good,but the outer sealing effect is relatively poor because of its short sealing edges.The little unbalanced force pushes the sealing block to te pumping chamber,therefore it is advantageous to meliorating the pump's sealing effect,thereby to improving it's volumetric efficiency as well.  相似文献   
7.
菱形目网片改制方形目网片工艺及方形目地拉网初步研究   总被引:1,自引:0,他引:1  
传统网具的网目形状一般为网线斜向交叉而构成的菱形,网目的菱形结构对网具的捕捞效能有多方面的影响。本文以探索通过改进网目形状而增强网具捕捞效能的可行性为目的,阐述了现有菱形目网片改制为方形目网片的工艺方法。文章对方形目网片地拉网参数确定及实际应用效果进行了分析和探讨。  相似文献   
8.
辽西阜新地区主要树种抗旱性的研究   总被引:6,自引:0,他引:6  
本文从显微结构,根系分布和水分生理生态特点等方面,综合研究了辽西半干旱地区主要树种的抗旱性。结果表明,侧柏、樟子松、蒙古栎、黄榆、元宝枫的抗旱性强,林分可在干年阳坡稳定生长;花曲柳适作伴生树种;油松、刺槐在造林初期生长良好,但在严重干旱年份未达成材生长便开始衰退,甚至枯干。前者适于阴坡造林,后者适于沟坡、沟底及山下腹坡脚处造林。  相似文献   
9.
10.
Cooloid concentrates were obtained by employing a cross-flow filtration system to ultrafiltrate seawater(which was pre-filtrated by 0.45 μm acetate cellulose membrane)sucessively with three membranes.The retentions(colloid concentrates)and control sample(in which colloid was removed)were then inoculated with a microalga and cultivated in vitro.After continuously monitoring cell content during cultivation,it was found that colloid had an obvious beneficial effect on the growth of microalga.Although colloids with different sizes influenced microalga‘s growth in different extent and ways,a brief conclusion could be draw from experiments that colloid might be a potential nutrition source for microalga‘s growth.  相似文献   
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