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71.
冷藏运输车厢温度场均匀控制研究   总被引:1,自引:0,他引:1  
为解决冷藏运输车厢内温度场分布不均匀直接导致杨梅等特色水果营养成分和品质变差等问题,通过正交试验法优化设计,引入温度场均匀性评价指标,分析了气流循环风机转速、匀流板孔隙率和货框垂直间距等因素对冷藏运输车厢内温度场的影响。结果表明:风机转速越高,温度场均匀性越好,厢内的最高温度基本不变;孔隙率越小,温度场均匀性越好,孔隙率0.1时厢内最高温度最低;在一定范围内垂直间距越小,最高温度越低,均匀性也越好。针对温度场中存在的"高峰"区域,基于场协同原理设计了冷藏运输厢体结构,通过调节右侧回风口处气帘风机的方向实现了均匀性控制。  相似文献   
72.
Mung bean trypsin inhibitor (MBTI) of the Bowman-Birk family was purified to homogeneity with a molecular mass of approximately 9 kDa on tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and 8887.25 Da as determined by matrix-assisted laser desorption/ionization-quadrupole ion trap-time-of-flight mass spectrometry (MALDI-QIT-TOF MS). Using blue scad myofibrillar proteins as targets, it was found that, in the absence of MBTI, proteolysis of myofibrillar proteins, especially myosin heavy chain (MHC), could be identified after incubation at 55 °C for 2 h, while in the presence of MBTI, with a final concentration of 25 ng/mL, proteolysis of these proteins was greatly suppressed even after incubation for 3 h. Although cysteine proteinase inhibitor E-64 was also effective in preventing protein degradation, inhibitors for metallo- and asparatic proteinases did not reveal obvious inhibitory effects. Our present results strongly suggested that the naturally occurring legume bean seed protein MBTI can be used as an effective additive in preventing marine fish blue scad surimi gel softening, which is quite possibly caused by myofibril-bound serine proteinase (MBSP).  相似文献   
73.
74.
Agarose is a natural seaweed polysaccharide and widely used in the medicine, food, and biological fields because of its high gel strength, non-toxicity, and electrical neutrality. The sulfate group is one of the main charged groups that affect the performance of agarose. In the present study, a simple, eco-friendly, and efficient method was explored for agarose preparation. After desulfation with hydrogen peroxide (H2O2), the sulfate content of agar reached 0.21%. Together with gel strength, electroendosmosis, gelling and melting temperature, the indicators of desulfated agar met the standards of commercially available agarose. Notably, the desulfated agar can be used as an agarose gel electrophoresis medium to separate DNA molecules, and the separation effect is as good as that of commercially available agarose. Further, the H2O2 desulfation process was analyzed. The addition of a hydroxyl radical (HO•) scavenger remarkably decreased the H2O2 desulfation rate, indicating that HO• has a certain role in agar desulfation. Sulfate content detection indicated that sulfur was removed from agar molecules in the form of sulfate ions (SO42−) and metal sulfate. The band absence at 850 cm−1 indicated that the sulfate groups at C-4 of D-galactose in sulfated galactan were eliminated.  相似文献   
75.
建筑模板用竹编胶合板生产工艺研究   总被引:1,自引:0,他引:1  
建筑模板用竹编胶合板系用毛竹经劈篾、编织、涂胶组坯、热压而成的竹材人造板。在生产中使用的半成品其含水率应控制在5~8%,胶粘剂在涂刷前需进行P型柔韧剂的改性和A型缓冲剂的调配,胶粘剂的用量为:竹席双面300~350g/cm~2,竹帘双面250~300g/m~2。热压工艺采用三段式,即低压保压——高压保压——降压保压,低压段在5~10 kg/cm~2单位压力下保持1~2 min,高压段在30~50 kg/cm~2单位压力下保持3~8 min,降压段在3~6kg/cm~2保持2~3 min。热压温度为130℃左右。  相似文献   
76.
采用 FSH、L H、PMSG、氟孕酮阴道海绵栓等激素进行超数排卵 ,通过人工授精、手术采卵、同期发情、胚胎移植、B超妊娠检查等技术 ,共处理优秀美利奴母羊 4 5 6只 ,获得可用胚胎 (A、B、C级胚胎 ) 30 33枚 ,平均 6 .6 5枚 /只(30 33/ 4 5 6 ) ,移植受体母羊 2 333只 ,冻胚受孕率 4 7.0 2 % (10 97/ 2 333) ,产羔数 14 2 6只 ,产羔率 12 9.99% (14 2 6 /10 97)。其中 ,公羔 6 85只 ,母羔 74 1只。优质细毛羊初生重公羔平均 4 .4 5 kg,母羔平均 4 .6 1kg。断奶重公羔平均38.2 4 kg,母羔平均 33.6 8kg。 12月龄平均体重公羊 76 .15 kg,母羊平均 6 2 .15 kg。周岁毛长公羊平均 11.6 7cm,剪毛量平均 12 .0 4 kg;母羊毛长平均 11.12 cm ,剪毛量平均 7.6 5 kg;平均净毛率达到 6 8.5 %。 2岁公羊体重平均 10 6kg,毛长平均 11.5 cm,剪毛量平均 11.85 kg,净毛率 6 9.5 %。2岁母羊体重平均 72 kg,毛长平均 11.0 cm,剪毛量平均8.5 kg,净毛率 6 9.0 6 %。羊毛纤维平均细度 18.71μm。 3岁公羊最大体重 14 8kg,母羊最大体重 10 2 kg。优质细毛羊新类群同期上述各项指标均显著或极显著高于中国美利奴羊  相似文献   
77.
本研究是在呼和浩特市的自然条件下,对紫羊茅种子产量在不同播种量和不同行距情况下进行了试验。结果表明,紫羊茅的最适播量7.50kg/hm2,行距为30cm,在此播种体系中种子产量平均可达662.5kg/hm2。  相似文献   
78.
海南省西甜瓜细菌性果斑病的发生与防治   总被引:1,自引:0,他引:1  
<正>近年来细菌性果斑病在海南西瓜、甜瓜生产上发生严重,其原因不仅与当地气候条件、栽培管理不当等有关,也与各地进行南繁的瓜类品种繁杂、种子消毒不彻底、病原远距离传播扩散有关。西瓜、甜瓜是海南省种植面积较为广泛、经济效益较高的农产品,2013年种植面积达1.97万hm2(29.55万亩)(农业部,2015)。细菌性果斑病是西瓜、甜瓜生产上的一种毁灭性病害,引起该病的病原菌为西瓜嗜酸菌(Acidovorax citrulli)(Schaad  相似文献   
79.
Y. Weng  M. D. Lazar 《Plant Breeding》2002,121(3):218-223
The greenbug, Schizaphis graminum (Rondani), is the most economically damaging aphid pest of wheat in the southern Great Plains of the USA. In this study, the single, dominant greenbug resistance gene, Gb3, was molecularly tagged and genetically mapped using amplified fragment length polymorphism (AFLP) and simple sequence repeat(SSR) markers. Three AFLP loci were associated with the Gb3 locus in linkage analysis with 75 F2:3 families from the cross between two near‐isogenic lines (NILs) for Gb3,‘TXGBE273’ and ‘TXGBE281′. Two of these loci, XMgcc Pagg and Xmagg Patg cosegregate with Gb3 in the population analysed. Further analysis indicated that XMgcc Pagg and Xmagg Patg are specific for the Gb3 locus in diverse genetic backgrounds. Two SSR markers, Xgwm111 and Xgwm428 previously mapped in wheat chromosome 7D, were shown to be linked with Gb3, 22.5 cM and 33.1 cM from Gb3, respectively, in an F2 population of ‘Largo’בTAM 107’, suggesting that Gb3 is located in the long arm of chromosome 7D. The two AFLP markers cosegregating with Gb3 are valuable tools in developing molecular markers for marker‐assisted selection of greenbug resistance in wheat breeding.  相似文献   
80.
The aim of this study was to assess brown rust resistance of new sugarcane varieties bred in China and main cultivated varieties in sugarcane planting area, and screen the elite new brown rust resistant varieties for popularization and application in production. In total, 60 new varieties in the national regional test of new sugarcane varieties were tested in Kaiyuan and Lincang, and 34 main cultivated varieties were studied in Lincang, Puer, and Yuxi, Yunnan province, and Yizhou, Guangxi province, China, where the incidence of brown rust was particularly high. The resistance of these sugarcane varieties to brown rust was investigated under natural inoculation and molecular marker-assisted identification was used to detect the brown rust resistance gene Bru1. The results of field survey showed that 66 (70.21%) of the 94 new and main cultivated varieties were highly resistant to moderately resistant, and 28 (29.79%) were susceptible to highly susceptible. Molecular detection indicated that Bru1 gene was found among 54 (57.45%) of the 94 new and main cultivated varieties. Some main cultivated varieties that were currently planted across large areas such as Guitang 29, Guitang 44, Dezhe 03-83, Liucheng 03-1137, Yuetang 60, and Guitang 46 were highly susceptible to brown rust, and 31 new varieties such as Yuegan 48, Funong 09-2201, Guitang 08-120, Liucheng 09-15, Zhongzhe 1, Yunzhe 08-1609, Yunrui 10-187, and Zhongtang 1201 were resistant. Therefore, in the sugarcane planting areas with high incidence of brown rust and wet and rainy climates, more effort should be eliminated the main susceptible varieties and promoted the application of new resistant varieties. This will help to achieve a reasonable distribution of varieties, fundamentally control the outbreak of disease in sugarcane planting areas, and provide security for the high-quality development of sugarcane industry in China in the future.  相似文献   
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