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山东省枣庄市山亭区桑村镇地处枣庄西北部,周围5公里内没有大型工厂,土壤肥沃,水质优美,是全市典型的无污染区,使无公害黄花菜(又称金针菜)种植获得了得天独厚的地理优势。因为种金针菜比种植其它农作物赚钱多(一般情况下,露地一级黄花菜卖到12元/千克,特级卖到15-16元/千克;大棚早期卖36-38元/千克。),且省时、省力,黄花菜便成了农民们的“香饽饽”。山亭区桑村镇王庙村青年农民、区农广校优秀学员陈家珍栽种的1亩黄花菜,年收益八千余元。现将其栽培技术介绍如下。1繁育壮苗黄花菜主要采用分株繁殖,时间在花蕾采毕后到冬苗萌发前,也可在冬苗枯萎后春苗抽生前的一段时间,但以前者为好。挖苗分苗时应尽量少 相似文献
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根据英国某权威医学杂志公布的美国军医的一项调查显示,部署在亚洲某地的美国海军陆战士兵中,90%都曾受到过攻击,大多数人都看到过战友阵亡或受伤.由于常期处于紧张状态和时刻面临危险,陆战队员的心理健康受到了严重的损害.该调查表明,1/6的上兵在完成任务后出现了心理问题,这个比例和"越战"时期不相上下. 相似文献
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底栖鱼类对水田上覆水中磷素动态的扰动效应 总被引:2,自引:0,他引:2
[目的]研究底栖鱼类泥鳅对水田上覆水中磷素动态的扰动效应,探讨生物扰动机制.[方法]基于模拟试验,使用离子色谱法和分光光度法,对比分析上覆水中磷素含量在有/无泥鳅活动时的差异.[结果]扰动组的TP、DTP和PP浓度在试验开始阶段与对照组无显著差异,在试验中、后期显著高于对照(P<0.05).扰动组要的PP/TP高于对照组,扰动组中TP浓度的增加主要是由于PP的增加,扰动组的DIP/DT在试验中、后期显著高于对照(P<0.05).[结论]底栖鱼类对水田上覆水中的磷素产生了扰动作用,增加了水稻生长可利用的的磷素养分.
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[Objective] The research aimed to investigate the bioturbation effects of benthic fish Misgurnus anguillicaudatus on phosphorus dynamic in overlying water of paddy field,as well as to explore the bioturbation mechanism.[Method]Based on simulation experiment,the phosphorus contents in overlying water were analyzed comparatively with and without Misgurnus anguillicaudatus by the using of ion chromatography and spectrophotometry. [Result] The concentrations of total phosphorus (TP),dissolved total phosphorus(DTP)and particular phosphorus(PP) in bioturbation group had no significant differences with those in control group in initial stage of experiment,and became significantly higher than control group in middle and late stages of experiment(P<0.05).The PP/TP ratios in bioturbation group were bigger than those in control group,the increase of TP concentration in bioturbation group was mainly due to the increase of PP.The ratios of dissolved inorganic phosphorus(DIP) to DTP (DIP/DTP) were significantly bigger than those in control group in middle and late stages of experiment (P<0.05). [Conclusion] The benthic fish had bioturbation effects on phosphorus in overlying water of paddy field,which increased the available phosphorus for rice growth. 相似文献
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王守红是安徽省临泉县长官镇人,在经历几次创业失败后,决定养牛.刚开始,王守红对养牛一窍不通,就去咨询畜牧专家,专家说:"养牛和养猪是不一样的,牛是草食动物,夏天你就多喂些青草,冬天就喂酒糟加青贮饲料."王守红跑到临泉一家酒厂,发现墙外扔掉的酒糟堆积如山,他如获至宝,雇辆大卡车,将酒糟拉回家. 相似文献
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氨基酸广泛应用于药品、饲料(鱼饲料、猪饲料)及添加剂,是氨基酸叶面肥的主要原料,武汉都兴农资有限公司开发出直接应用于农作物作肥料施用的"都兴隆"氨基酸原粉,其优点有:1.养分含量高内含17种氨基 相似文献
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In this article we examine the economic benefits of the long history of public research in agriculture. Agricultural productivity continues to grow. Annual rates of return on research expenditure are of the order of 50 percent. Research oriented to science is profitable when associated with technological research. Decentralization, as in the system of state agricultural experiment stations and substations, has allowed close association of research oriented to science with that oriented to technology and to farming. The high rate of return shows that investment in public research in agriculture is too low. This is at least partially because research benefits spill over to other regions and to consumers, reducing the incentives for local support. 相似文献
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Measurements of broadband radio noise in the range 73 to 440 megahertz were made over several small Illinois cities during August, September, and December 1972. Results for cities with a population larger than 25,000 are presented as brightness temperatures between 2400 and 9600 degrees Kelvin. Even the smallest villages produce significant noise pollution. There is considerable diurnal variation and some evidence for seasonal variation. 相似文献
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研究新疆核桃分心木中总黄酮提取工艺及响应面优化。[方法]利用超声波辅助提取法进行提取,采用紫外光谱法对新疆分心木中总黄酮含量测定及提取率计算,采用响应面法对提取工艺进行优化。[结果]得到最佳的实验提取工艺流程为55.75%乙醇,料液比1:20.50(g/mL)。超声提取31.69min,功率为630.68W。此条件下总黄酮含量可达22.2144%。[结论]该工艺稳定可用于新疆分心木中总黄酮提取。 相似文献
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在对微波辅助提取苦丁茶总黄酮的工艺优化研究过程中,利用单因素实验确定乙醇浓度、提取温度、料液比及提取时间4因素的单因素最佳值.然后通过单变量多因素方差分析来选定3个对总黄酮提取率影响最大的因素来进行BBD(Box-Behnken Design)响应面优化,从而确定它们的最优组合.实验结果表明,各单因素实验的最佳值为:乙醇浓度50%,提取温度80℃,料液比1∶20,提取时间8min;乙醇浓度、提取温度及料液比对总黄酮提取率的影响最为显著,其影响顺序依次为:料液比、乙醇浓度、提取温度;响应面分析得到的苦丁茶总黄酮提取的最佳工艺条件为:乙醇浓度50.75%,料液比1∶21.6,提取温度80.35℃,总黄酮提取率为7.622 86. 相似文献
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昆虫在约4亿多年的进化过程中,成功地发展了多种多样的适应与生存绝技。创新科技的运用使科学家们能够解析不同昆虫新奇的化合物和特性,并将其用于工业和医学领域的仿生学研究。如受昆虫行走启发设计的机器人,根据昆虫色彩创造的军事伪装术,通过模拟昆虫飞行制造的微型探测器等,处处体现了来自昆虫的灵感。 相似文献