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971.
宽柄芥新品种渝芥1号是从地方品种包包菜的变异单株中,历经6个世代单株自交纯化、定向系统培育而成。该品种熟性晚,叶片及中肋宽大肥厚,加工性状好。最大叶片长70~75cm、宽25~30cm,中肋长35~40cm、宽12~15cm、厚1.1cm左右,单株商品鲜质量2.0~2.5kg,单叶柄肋鲜质量210g左右,单株经济有效叶片数7片以上。一般每667m2商品产量7000kg左右,高产栽培可达8000kg以上。适宜在重庆、四川及云贵地区作酸菜加工原料栽培,也可鲜食。 相似文献
972.
为了探明钾硅钙微孔矿物肥对污染稻田土壤重金属镉(Cd)有效性的影响,弄清其对稻谷中Cd含量的降低效果。采用田间小区试验和室内分析测定方法进行研究,试验设5个处理,处理1:对照(CK),常规施肥(40%复合肥450 kg/hm2);处理2:钾硅钙微孔矿物肥600 kg/hm2+常规施肥;处理3:钾硅钙微孔矿物肥750 kg/hm2+常规施肥;处理4:钾硅钙微孔矿物肥1125 kg/hm2+常规施肥;处理5:钾硅钙微孔矿物肥1425 kg/hm2+常规施肥。结果表明:钾硅钙微孔矿物肥可以显著提高水稻穗总粒数、穗实粒数和结实率,提高水稻产量,增产率达到7.5%~16.0%;增加土壤碱解氮、有效磷和速效钾含量,提高土壤pH值,降低土壤有效Cd含量,从而降低稻谷Cd的积累,最大降低稻谷Cd含量达到38.6%。钾硅钙微孔矿物肥要达到降阻水稻重金属Cd的最佳效果,施用量不能低于1425 kg/hm2。 相似文献
973.
As an adjuvant, cytokine plays a key role in regulating the innate and adaptive immunity and enhancing the vaccine specific immune responses. The researches on the interleukin, interferon, granulocyte macrophage colony stimulating factors, tumor necrosis factors, and chemotactic factor have made considerable progress. Now we reviewed the cytokine adjuvant application in order to provide reference for the future application. 相似文献
974.
In order to obtain higher purity and high yield of LPS isolated from Escherichia coli, and evaluate its virulence,excrement of diarrhea piglet was collected as pathological samples, of which, some strains of Escherichia coli were isolated and identified. And furthermore, a strain of Escherichia coli was acquired by 16S rDNA identification. The LPS from this strain of Escherichia coli was isolated with the hot-phenol water method and purified by DNaseⅠ, RNaseA, proteinase K treatment and alcohol precipitation. The polysaccharide, protein and nucleic acid content of purified LPS were detected by phenol-sulfuric acid method, Bradford method and UV points spectrophotometric method. And its bioactivity and acute median lethal dose was determinated by tachypleus amebocyte lysate (TAL) method and acute toxicity experiment method, respectively. The results showed that a strain of highly pathogenic Escherichia coli was successfully isolated. The average yield of purified LPS was 3.74%, the proportion of the polysaccharide was 13.40%, the protein was 0.48%, and the nucleic acid was 0.06%. SDS-PAGE electrophoresis and silver stain showed that the bands were mainly concentrated in the range of 14 to 160 ku. The LAL bioactivity of the prepared LPS was 1.21×107 EU/mg, LD50 of the mouse abdominal cavity was 31.86 mg/kg. The results revealed that the diarrhea piglets in the farm was caused by pathogenic Escherichia coli,purified LPS from this strain of Escherichia coli had the advantages of higher purity, high yield and strong virulence, which would provide theoretical data for clinical prevention and treatment of diarrhea piglets. 相似文献
975.
职业学校钳工实习教学的钻孔是钳工专业一项重要基本操作技能,要求进行系统的技能和技巧训练,掌握加工要求较高的孔及位置精度的方法。但由于钻孔中的累积误差很难完全消除,钻孔的位置精度也就很难保证,因此如何消除或减少钻孔的误差是钳工实习教学中的难点和终点。文章从钻孔误差产生的原因和防止方法两个角度出发,探索了钳工实习教学中,如何消除或减少钻孔误差的教育教学生产实践。 相似文献
976.
残料加工对编程来说是一个比较复杂的环节,不同的软件拥有不同的功能,对不同形状的零件有不同的加工方法,文章针对UG CAM模块,了解其残料加工的原理,优化这些加工方法,追求更安全、更高效的残料粗加工方法。 相似文献
977.
Investigation into the paternity of four abaca (Musa textilis L, Nee) hybrids was done to ascertain the mode of transmission of selected morpho-agronomic traits and to detect possible heterosis. In situ morphological characterization was undertaken using twenty five qualitative and six quantitative characters. Results revealed that a great majority of the qualitative traits were shared by both parents and their hybrids. For the rest, the qualitative traits were inherited from one or the other parent though some variant phenotypes (i.e. chimerism) were also noted in the hybrids. Cases ofheterosis were also observed and this could be exploited to increase fiber yield in the hybrids. Though inconclusive due to factors such as the heterogenous nature of abaca plants in the field and the susceptibility of morphological traits to environmental fluctuations, this study has provided baseline information on abaca hybridity that can be verified using more robust technologies as molecular markers. 相似文献
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980.