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991.
针对加湿梗成品含水率控制稳定性差、湿透率低的问题,对稳定控制一次回潮热水温度、二次回潮蒸汽压力、二次回潮加水量环节进行了系统研究,采用统计过程控制技术对加湿梗成品含水率进行控制,以提高加湿梗含水率的稳定性。通过正交试验优化了3个主要工艺参数,并进行直观分析以及生产验证,结果表明最佳工艺组合为:一次回潮水温60℃,二次回潮蒸压力0.65 MPa,二次回潮加水量0。 相似文献
992.
Accurate obtainting soil parameters of landslide is the key links for landslide stability evaluation and project management . This article takes Shennv Stream landslide in Chongqing Wushan County as an example, implementing unconsolidated and undrained shear test and mineral composition analysis by X ray diffraction for soil in different elevations of landslide ,conducting sensitivity test for various soil parameters of reservoir landslide change with different water level.Study shows that : Mineral composition of soil mainly contains Calcite, Quartz and clay mineral. Hydrophilic minerals in clay mineral have great effect on stability of landslide. Shear strength decreases by influence of water content on cohesion. Cohesion decreases sharply in a quadratic function relation with water content increasing .When water content comes to 18.21% ,change of cohesion tends to be stable.But the internal friction angle of landslide soil decreases linearly in small amplitude with an increase of water content. Research results may provide some important references for rationally choosing strength parameters of soil in similar landslide. 相似文献
993.
Micro-surfacing mix has been wildly used in the pavement maintenance for its water proofing, anti-skidding and wear resistance. However, micro-surfacing pavement has higher noise than the common asphalt pavement and its noise can not be measured effectively and accurately. Therefore, the indoor noise test method of micro-surfacing mix based on wet track abrasion test was explored. The micro-surfacing mix specimens were used to imitate the micro-surfacing pavement. The wet track abrasion tester was used to provide the vehicle loads. The sound level meter was used to measure the noise between tire and pavement. Furthermore, the indoor noise of nine kinds of micro-surfacing mixes with different gradation was examined. The results show that the equivalent sound level in the second time period has good relationship with the surface texture depth by sad patch method. Then the test method and test procedure for the indoor noise of micro-surfacing mix based on wet track abrasion test were given. Finally, two micro-surfacing mixtures with different gradations were made to validate the test method. The results show that the evaluation method can effectively distinguish the difference of micro-surfacing mixes with different gradation and can supplement the mix design method of micro-surfacing mixes. 相似文献
994.
Mathematical modes of engine,cooperation of motor and batteries,automatic clutch and vehicle are built with analysis of configuration of plug-in hybrid electric vehicle (PHEV). Specifications of data input and output and signal characters are defined. Hardware in the loop (HIL) system based on MATLAB/xPC for PHEV is built up. The motor/engine drive shift control logic test of PHEV is carried with inputting real acceleration pedal data. Testing results show that automatic clutch acts abnormally. Bugs in control logic are found out. Road test results with revised control logic are very good. 相似文献
995.
Experimental analysis of the abrasive belt follow-up grinding of Zirconium-4 alloys tubes and pipes 总被引:1,自引:1,他引:0
Abrasive belt grinding experiments of Zr-4 nuclear power tube are carried out by using three different abrasive belts with same size, and the interactive generating mechanism between abrasive and workpiece is analyzed, the main factors of material removal rate and surface roughness of Zr-4 alloys are obtained. With the help of the advanced test facilities, the abrasive grain abrasion and surface topography of the workpiece are observed. The metallographic structure and microhardness of the layer of burnt surface during Zr-4 alloys Grinding are analyzed. Some conclusions are given as follows: the material removal rate and surface roughness are mainly affected by the factors of belt speed, grinding pressure, hardness of the contact wheel and abrasive type, of which, the belt speed is the strongest factor. The adhesion wear of the Zirconium corundum and aluminium oxide abrasive grit is more serious, the most important wear form of silicon carbide is abrasion wear. With the onset of grinding burn, the mechanical properties of Zr-4 alloys are deteriorated obviously. The results provide a theoretical and experimental basis for technical optimization in the grinding of Zr-4 alloys with efficiency and high quality. 相似文献
996.
Background
We suggest a ‘screening test’ to examine large data files with clinical ratings for the occurrence of rater-introduced bias prior to using the data for quantitative analyses. The test is based on a statistical model in which a well-standardized interval-scale outcome (for example, milk yield) is related to clinical ratings (for example, body condition scores) obtained from multiple contexts (for example, dairy herds).Findings
84,968 calvings from 279 herds, with subsequent body condition scores performed by 117 veterinarians within the first 21 days postpartum were analyzed with a multilevel random coefficient regression model. The model included an independent variable, where body condition score was centered within veterinarian. This is a so-called comparison effect to describe possible rater-introduced bias in the body condition scores. A highly significant comparison effect was found for second and older parities, indicating occurrence of possible rater-introduced bias in this large multi-herd data file.Conclusions
A within-group centering technique (the comparison effect) appeared to be useful for discriminating between biased and unbiased clinical scores. In some cases, this test for bias should prevent further analysis of the data and divert the focus of study to the calibration of raters or alternative study designs. 相似文献997.
998.
以烟台地黄瓜为材料,研究了百泰、凯润、安克、克露、乙膦铝和代森锰锌等药剂在发病前和发病后施药对保护地黄瓜霜霉病的预防及防治效果,以及对黄瓜产量的影响。试验结果表明,发病前喷施百泰、凯润效果最好,防效在97%以上;安克、克露、代森锰锌防效次之,防效也高达88%以上;乙膦铝防效较差,为81.00%。发病后喷施凯润防效在93.83%以上,百泰、安克和代森锰锌防效都在80%以上。发病后喷施百泰、凯润和安克比CK(清水)分别增产18.46%、24.36%和22.22%,增产效果明显。因此推荐凯润为防治保护地黄瓜霜霉病的理想药剂,百泰、安克和代森锰锌可以作为保护性杀菌剂使用。 相似文献
999.
2009—2010年广西甘蔗品种区域试验舍浦试点结果表明:桂糖02/281宿根性好,蔗茎产量高,比新台糖22号(CK1)和新台糖16号(CK2)增产显著,公顷舍糖量最高,但平均蔗糖分(13.80%)最低,分别比CK。和CK2减少1.59和0.66个百分点。园林17、柳城04/12、桂糖03/2357、桂糖02/1156、桂糖02/649、桂糖03/1403、桂糖03/963和桂糖03/2625的蔗茎产量及平均蔗糖分表现均不突出。 相似文献
1000.