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51.
土壤调理剂对滨海吹填土的改良效应 总被引:2,自引:0,他引:2
采用蘑菇棒、锯末、诺沃肥、脱硫石膏组成的土壤调理剂,通过调理剂掺拌和水力淋洗相结合的方法,对滨海吹填土进行土壤改良试验,检验该调理剂改良吹填土的可行性,并确定调理剂的最佳用量。研究结果表明:调理剂可有效改善土壤物理性状,减小土壤容重,增大渗透率和非毛管孔隙度。调理剂的使用虽然没有明显改变吹填土土壤盐分的去除总量,但可以有效提高土壤脱盐效率,减少洗盐用水量,试验组用水量为对照组的69.23%。其所去除的盐离子以Cl~-和HCO_3~-为主。调理剂减弱了土壤溶液中盐分对植物的毒害作用,其自身也为植物提供了所需养分;随着调理剂用量的升高,植物生物量也相应增大。综合考虑使用土壤调理剂对滨海吹填土的改良效果,确定其最佳用量为15%。 相似文献
52.
靠小流域治理开发奔小康途径初探曹丽玫(黄委会黄河上中游管理局,西安710043)通过治理开发,建设小流域经济,从而加快山区农村奔小康的步伐,是社会主义市场经济的需要。不同类型区、不同面积、不同社经情况和不同自然环境的小流域,治理策略不同,主导产业与拳... 相似文献
53.
贵州省贵定县定东小学滑坡形成机制 总被引:1,自引:0,他引:1
[目的]贵州省贵定县定东小学滑坡发生后,造成学校食堂、住宿楼地面、墙体出现开裂,直接威胁学校建筑物及附近民房、道路安全,迫切需要查明其形成的机制,为滑坡工程治理提供可靠的依据。[方法]采用了钻探、浅井、高密度电法等手段和方法调查了滑坡体结构和变形特征,并用Adina软件分析了滑坡在自然和暴雨情况下应力应变场和变形破坏特征。[结果]人工填土和降雨是滑坡形成的主要原因,滑坡破坏模式为蠕滑拉裂型。特殊的地形地貌和低压实度填方是导致滑坡最主要的内因,而长时间的降雨入渗是外因。[结论]不合理的人工填土是滑坡发生的直接原因,滑坡会沿填土与黏土层交界面处发生滑动。 相似文献
54.
室内淋洗条件下脱硫石膏对滨海吹填土理化性质的影响 总被引:2,自引:0,他引:2
为改善吹填土的理化性质,实现吹填土在城市生态建设方面的充分利用,通过室内土柱淋洗试验,研究在不同施用量下脱硫石膏对吹填土各种离子动态变化的影响。结果表明:脱硫石膏可以显著改善滨海吹填土的理化性质,脱硫石膏施用量分别为0.7%,1.4%,2.1%,3种处理下土柱的饱和导水率分别是6.21,7.41,9.51mm/h;淋洗后土壤电导率、Na+和Cl-浓度、钠吸附比(SAR)和碱化度(ESP)等指标较淋洗前均有90%以上的降幅程度;且在前20h的淋洗过程中,各种化学指标的下降效果最为明显,而在将近150h的剩余时间内虽有下降,但下降速率很缓慢。 相似文献
55.
本文着重讨论了头屯河水库泥沙淤积问题,详细分析了头屯河入库水沙特性和水库泥沙淤积的原因及影响因素,运用灰色动态模型对水库泥沙淤积的趋势进行预测,指出水库排沙减淤的可能性.为恢复水库库容提供理论依据。 相似文献
56.
Effect of high temperature on albumin and globulin accumulation in the endosperm proteome of the developing wheat grain 总被引:1,自引:0,他引:1
William J. Hurkman William H. VenselCharlene K. Tanaka Linda WhitehandSusan B. Altenbach 《Journal of Cereal Science》2009
The accumulation of KCl-soluble/methanol-insoluble albumins and globulins was investigated in the endosperm of developing wheat (Triticum aestivum, L. cv. Butte 86) grain produced under a moderate (24 °C/17 °C, day/night) or a high temperature regimen (37 °C/28 °C) imposed from 10 or 20 days post-anthesis (dpa) until maturity. Proteins were separated by 2-DE and developmental profiles for nearly 200 proteins were analyzed by hierarchical clustering. Comparison of protein profiles across physiologically equivalent stages of grain fill revealed that high temperature shortened, but did not substantially alter, the developmental program. Accumulation of proteins shifted from those active in biosynthesis and metabolism to those with roles in storage and protection against biotic and abiotic stresses. Few proteins responded transiently when plants were transferred to the high temperature regimens, but levels of a number of proteins were altered during late stages of grain development. Specific protein responses depended on whether the high temperature regimens were initiated early or mid development. Some of the heat responsive proteins have been implicated in gas bubble stabilization in bread dough and others are suspected food allergens. 相似文献
57.
Association of rumen fill score and energy status during the close‐up dry period with conception at first artificial insemination in dairy cows 下载免费PDF全文
Chiho Kawashima Chihiro Karaki Megumi Munakata Motozumi Matsui Takashi Shimizu Akio Miyamoto Katsuya Kida 《Animal Science Journal》2016,87(10):1218-1224
Recent studies have shown significant associations between prepartum energy status and postpartum fertility in dairy cows; therefore, the assessment of energy status by blood metabolites and metabolic hormones and suitable improvement of management during the prepartum period may enhance reproductive performance. Rumen fill score (RFS) is associated with feed intake; however, it is unknown whether RFS is also related to blood parameters. Therefore, this study investigated the relationship between RFS and energy status during the prepartum period, and their associations with conception at first artificial insemination (AI) after parturition. In 42 multiparous Holstein cows, RFS assessment and blood sampling were carried out twice a week during 3 weeks of the peripartum period. Ovarian cycles until AI were evaluated by measuring milk progesterone levels. Before calving, positive correlations were observed between RFS and total cholesterol, and RFS did not change in pregnant cows at first AI after parturition, whereas in non‐pregnant cows, RFS decreased gradually as the calving day approached. After calving, non‐pregnant cows showed lower energy status compared with pregnant cows, and some non‐pregnant cows showed anovulation and cessation of estrous cycle. In conclusion, RFS during the close‐up dry period is related to real‐time energy status, and is associated with postpartum energy status and conception at first AI in dairy cows. © 2016 Japanese Society of Animal Science 相似文献
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59.
通过对不同时期植被袋中填充基质的理化性能测定分析,确定植被袋有较好的保水性、保温性及保肥性,能适应公路劣质边坡的恶劣环境,能达到生态防护的效果. 相似文献
60.
结合邵怀高速公路溆浦连接线半填半挖路基的实际情况,应用有限元软件,采用Drucker-Prager弹塑性模型及四节点Goodman摩擦单元,对加筋切填路基变形影响因素的敏感性进行了模拟试验;通过定义敏感性因子对试验结果进行了分析,并对各影响因素敏感性进行了排序.结果表明:对路堤顶面沉降影响因素敏感性排序前3位的依次为地基强度、路堤高度和加土工格室;对坡脚底部侧向位移影响因素敏感性排序前3位的依次为地基强度、加土工格室和路堤高度.试验显示了加筋切填路基的真实工作状态,结果可为同类型的后续研究和工程实践提供参考. 相似文献