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11.
钢辊式圆捆打捆机结构改进与试验   总被引:8,自引:0,他引:8  
为解决小型钢辊式圆捆捡拾打捆机秸草打捆时的堵塞问题,对其结构进行了改进试验。在试验中,采用了增加喂入单辊、喂入对辊结构,并对其喂入能力、可靠性指标进行了测定。经过结构改进试验,得出配有喂入对辊(上辊沿轴向配置高19.5mm、直径160mm、间距48mm圆环,下辊直径160mm、沿周向配置高6.5mm横板)的钢辊式圆捆打捆机可较好地解决秸草打捆中的堵塞问题,并能扩大其适用范围,提高其工作性能和工作可靠性。  相似文献   
12.
朱俊玲  卢智 《安徽农业科学》2011,39(13):7695-7696,7698
[目的]研究海带的脱腥工艺和复合果丹皮的配方。[方法]以海带、苹果、胡萝卜等为主要原料,通过正交试验优选复合果丹皮的最佳工艺配方,并用绿茶进行了海带的脱腥处理试验。[结果]用浓度为1.5%的茉莉花茶60℃处理海带10 min可脱腥。复合果丹皮的最佳配方:苹果浆∶海带浆∶胡萝卜浆为2∶1∶1,加糖量为30.00%,柠檬酸0.90%,海藻酸钠0.10%调配,在60℃下干燥6.0 h。[结论]在最佳工艺条件下,可得色泽、风味、口感较好的果蔬复合果丹皮。  相似文献   
13.
喷药治蚜防病试验中,溴氰菊酯和久效磷对豆蚜(Aphis craccivora)的防效分别达到96.7%和67.1%。两次和三次施用溴氰菊酯的防病效果分别达到84.1%和86.1%,蚕豆产量分别比未施药对照增产17.7%和21.9%。施药也影响蚕豆黄化卷叶病的时间分布型,三次施药小区的病株始终为泊松分布,病害没有再次扩散;未施药小区早春病株就出现负二项分布,越冬前病害已经扩散。豆蚜蚜害率与蚕豆黄化卷叶病发病率密切相关。  相似文献   
14.
GB19725—2005《便携式割灌机和割草机安全要求》中,附录C抛物试验是GB/T14176—2003《便携式割灌机和割草机技术条件》3.6安全要求中重要的检测项目。根据抛射物体的形状和抛射物体试验的要求,开发设计了抛射物体试验台,以完善割灌机安全性能试验项目的检测。  相似文献   
15.
It is unclear how effective different types of broiler carcass wash steps are in lowering the presence or numbers of pathogenic bacteria. We tested for individual and combined effectiveness of 5 separate on-line wash steps applied between bleed-out and chilling in a commercial broiler processing plant. Carcasses were sampled directly before and after each wash step: pre-scald brush washer, post-feather pick (New York dressed) spray washer, inside/outside spray washer, postevisceration brush washer, and final prechill spray washer. Carcasses were examined for numbers of Campylobacter and Escherichia coli and presence of Salmonella using standard cultural methods. Overall, numbers of Campylobacter were lowered from log 2.58 to 1.15 cfu/mL of carcass rinse, but no single wash step caused a significant decrease. Overall, Salmonella prevalence was decreased from 80 to 24%; however, no wash step caused a significant decrease by itself. The 5 wash steps in series lowered E. coli numbers from log 4.60 to 2.69 cfu/mL; the New York-dressed spray wash and the postevisceration brush washer each had a significant effect on E. coli. When examined separately, the benefit of broiler carcass wash steps may not be evident. However, when combined with overall processing, wash steps can be effective to lessen bacterial contamination on carcasses and be useful for pathogen control. Additional studies are necessary to maximize the effectiveness of carcass washers.  相似文献   
16.
新型自走式割灌机结构分析   总被引:1,自引:0,他引:1  
介绍了一种新型自走式割灌机.该机由行走、割灌、驾驶台及排障四个核心部分组成,可以锯切直径为10~80 mm的灌木.本文对其行走部分和驾驶台进行了系统介绍,并对其主要部件进行了参数设计.  相似文献   
17.
连续生产中、高密度薄板的方式是采用连续双钢带冷热压机,而国内人造板设备制造行业尚无制造连续双钢带冷热压机的能力。本文依据木纤维薄板矫直原理,提出采用简易连续热辊压压机加矫直机的方案,探索低成本连续生产中、高密度纤维薄板和异型板的方式,以解决实际生产问题。  相似文献   
18.
为研究灌木平茬机在科尔沁沙地的通过性能,基于ADAMS/ATV建立了其虚拟样机模型及符合沙地特性的平地、坡路、垂直障碍、凹坑、正弦路面等虚拟地形,进行了灌木平茬机在典型路面上行驶的仿真分析。结果表明,灌木平茬机能够平稳通过所建立的虚拟地形,在沙地上具有较好的通过性能,转向平稳。根据仿真结果确定灌木平茬机主动轮的最佳直径为280 mm、转向半径为0.75 m。  相似文献   
19.
Ontogenetic changes in digestive tract histology and digestive enzyme histochemistry were investigated 11 to 36 days post-hatch in white sturgeon Acipenser transmontanus larvae. From initiation of exogenous feeding (12 days post-hatch), larvae were fed a commercial salmonid diet for the ensuing 24 days. The digestive system of white sturgeon displayed a high degree of morphologic organization and functionality at the onset of exogenous feeding. An enhancement of digestive capacities occurred with transition to active feeding. On day 2 of feeding, there was a clear increase of alkaline phosphatase, aminopeptidase M, dipeptidyl peptidase IV, and -glutamyl transpeptidase activity in the brush border of the spiral intestine. This strong activity is an apparent confirmation of the importance of this segment of the intestine for protein digestion and nutrient absorption. The functional development of the pyloric intestine occurred on day 4 and was concomitant with an increase in the activity of brush border and cytoplasmic enzymes such as acetylcholinesterase, dipeptidyl peptidase II, - and -galactosidases. The absence of acetylcholinesterase, lactase, nonspecific esterase, and weak activity of exopeptidases and alkaline phosphatase in the anterior intestine suggests that this segment of the intestine may be less important in nutrient absorption than the pyloric and spiral intestines. The observed quantitative and qualitative differences in enzyme activity along the intestine indicate a high degree of specialization of each segment for specific digestive and absorptive processes.  相似文献   
20.
Triplicate groups of juvenile seabass (initial weight of 241 g) were fed during 13 weeks three isonitrogenous experimental diets containing different lipid levels, 12% (LL group), 21% (ML group) and 30% (HL group). At the end of the experiment, fish weight gain was similar among the 3 dietary groups. Intestinal brush border membranes were purified for each dietary group; one part of the brush border fraction was dedicated to enzyme assays, the remaining fraction being used for lipid extraction followed by fatty acid analysis. The fatty acid composition of the brush border membrane differed among the 3 groups, although the 3 experimental diets had the same fatty acid composition. The increase in dietary lipid level resulted in a lowering in (n-3) polyunsaturated fatty acid (PUFA) paralleled with an increase in monounsaturated fatty acid. A significant reduction in the brush border enzyme activities, namely alkaline phosphatase, aminopeptidase N, -glutamyl transpeptidase and maltase, was also observed with the elevation of the dietary lipid level. The change in activity of intestinal digestive enzymes, which are membrane-bound proteins, could be attributed to the modification of fatty acid composition and fluidity of the brush border membranes (BBM). Such lowering in PUFA and increase in monounsaturated fatty acid in BBM, concomitant with a decline in membrane enzymatic activity, has been described as a malnutrition indicator in mammals. It raises the question of possible disorders of gut functions in fish fed increasing lipid levels.  相似文献   
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