604 research outputs found

    Medicinal Bioresources

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    鼠腹腔中弓形虫的增殖发育及S.D.对其的影响

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    对鼠腹腔中弓形虫速殖子的增殖发育的方式、过程及 S.D.对其的影响作了详细的考察 ,结果表明弓形虫的无性生殖方式有内二裂殖、纵二裂殖、裂殖生殖等 ,虫体以鼠腹腔内巨噬细胞的胞壁作为假包囊壁在其中增殖发育 ,经过 72 h的增殖生长 ,虫体成熟后突破假包囊逸出 ,S.D.可部分抑制速殖子增殖

    2019年秋季鲍鱼生产形势调研分析

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    福建、山东、辽宁、浙江、广东和海南是全国鲍主要养殖省。本文介绍了全国鲍主产区分布及总体情况,分析了秋季鲍生产形势及特点,指出了存在的问题,并给出了合理建议。为全面了解2019年全国鲍秋季养殖生产形势及发展趋势,9月下旬至10月中旬,鲍鱼调研组采取电话调查、问卷调查与现场调研的方式,对福建漳州、莆田、福州、宁德和平

    双能谷效应对N型掺杂Si基Ge材料载流子晶格散射的影响

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    性能优越的Si基高效发光材料与器件的制备一直是Si基光电集成电路中最具挑战性的课题之一.Si基Ge材料不仅与成熟的硅工艺相兼容,而且具有准直接带特性,被认为是实现Si基激光器最有希望的材料.对Si基Ge材料N型掺杂的研究有利于提示出其直接带发光增强机理.本文研究了N型掺杂Si基Ge材料导带电子的晶格散射过程.N型掺杂Si基Ge材料具有独特的双能谷(Γ能谷与L能谷)结构,它将通过以下两方面的竞争关系提高直接带导带底电子的占有率:一方面,处于Γ能谷的导带电子通过谷间光学声子的散射方式散射到L能谷;另一方面,处于L能谷的导带电子通过谷内光学声子散射以及二次谷间光学声子散射或者直接通过谷间光学声子散射的方式跃迁到Γ能谷.当掺杂浓度界于1017cm-3到1019cm-3时,适当提高N型掺杂浓度有利于提高直接带Γ能谷导带底电子占有率,进而提高Si基Ge材料直接带发光效率.国家自然科学基金青年基金(批准号:61604041);;福建省自然科学基金青年基金(基金号:2016J05147);;福建省教育厅2017年高校杰出青年科研人才培育计划项目;;福建工程学院校科研启动基金(批准号:GY-Z14073)资助的课题~

    Food source and feeding habit of Helice tientsinensis from the common reed vegetation in high marsh of Yellow River Delta,China

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    Investigating the composition of food sources with stable isotope method can provide direct evidence for the top-down control in the coastal wetland.In this study,we examined food source and feeding habit of Helice tientsinensis of common reed (Phragmites australis) vegetation in high marsh of Yellow River Delta.The results showed that the density of crab was (5.5 1.5) ind&middot;m~(-2),with the behavior of climbing P.australis to feed on the leaves at night.Under the same indoor experimental condition,H.tientsinensis showed feeding preference on fresh leaves of P.australis.The stable isotope food source analysis showed that the leaves of P.australis were one of the important food sources of H.tientsinensis in the field.There were temporal variations in the proportion of fresh leaves [May:(6.44.9) %,July:(5.84.9) %,September:(12.58.8) %] and dead leaves [May:(12.47.8) %,July:(15.59.9) %,September:(15.19.4) %].Therefore,H.tientsinensis could inhibit P.australis&#39;s growth and affect litter decomposition through feeding disturbance behavior.</p

    Comparative studies on carbon storage and litterfall dynamics between secondary and primary mangrove communities in Zhanjiang,Guangdong Provinces,China

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    通过群落调查、异速生长法计算以及样品测定,分别对2010~2011年期间广东湛江高桥红树林生态系统中次生桐花树和原生木榄群落的植物和土壤储量进行了计算,并利用掉落物收集筐对掉落物动态进行了比较研究。研究结果表明,高桥桐花树与木榄群落的植物碳库(以C计,下同)分别为(51.16±12.06)x106g/HM2和(38.52±6.94)x106g/HM2,地上部分明显高于地下部分;土壤碳库分别为(111.86±7.96)x106g/HM2和(106.13±11.12)x106g/HM2,明显高于植物碳库;次生与原生红树林群落的总碳库没有差异(P>0.05)。桐花树和木榄群落的年均掉落物产量分别为556.00 g/M2和971.13 g/M2,均以凋落叶居多,但原生木榄群落的掉落物产量明显高于次生桐花树群落(P 0.05).The mean annual litterfall production for the B.gymnorrhiza community was 971.13 g DW / m2,significantly higher than that of the A.corniculatum community( 556.00 g / m2,P < 0.001).In conclusion,the carbon pools in the secondary A.corniculatum community were comparable with those for the primary B.gymnorrhiza community,but much lower than those for the primary mangrove communities in the tropical regions.国家自然科学基金重点项目(30930017); 国家海洋公益性行业科研专项经费项目(200905009;201305021
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