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Search Results: 1 - 10 of 305633 matches for " 张利红 "
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辽河和大辽河水质指标的空间变化
Space Variation of Water Quantity Parameters in Liao River and Daliao River
 [PDF]

, 徐成斌
Advances in Environmental Protection (AEP) , 2013, DOI: 10.12677/AEP.2013.31B003
Abstract:
本文对辽河12个断面和大辽河3个断面的水质参数:pH、溶解氧、COD、BOD5、氨氮和总磷的空间变化进行了研究。结果表明,辽河和大辽河流域15个监测断面水体的pH值都大于7;辽河上游到下游COD、BOD5呈上升的趋势,大辽河3个断面都达到劣Ⅴ类;监测断面中有接近70% 断面总磷,80%断面氨氮都达到劣Ⅴ类;辽河和大辽河的污染非常严重。

Space variation of water quantity parameters including pH、DO、COD、BOD5、ammonia nitrogen and total phosphorous were investigated in 12 sections of Liao River and 3 sections of Daliao River. The results showed that pH values in 15 sections were above 7. The trends of COD and BOD5 from upstream to downstream in LiaoRiverwere gradually increased. The values of COD and BOD5 in 3 sections of Daliao River reached interior V class. The values of ammonia nitrogen about 70% of all sections and total phosphorous about 80% reached interior V class.LiaoRiverandDaliaoRiverwere seriously polluted.
雄烯二酮和甲基睾酮对日本鳗鲡血清睾酮和17_雌二醇含量的影响

水产学报 , 2001,
Abstract: 探讨了间隔15d多次埋植雄烯二酮(4-androstene-3,17-dine,adsd)或甲基睾酮(17α-methyl-testosterone,mt)诱导日本鳗鲡性腺发育过程中,血清睾酮(testosterone,t)和17β-雌二醇(17β-estradiol,17β-e2)含量的变化.在雌鳗中,埋植adsd后血清t和17β-e2含量显著升高,随后缓慢下降;埋植后第15d的血清t含量随埋植次数的增加呈下降趋势,而血清17β-e2含量随埋植次数的增加而逐渐增加.埋植mt则使雌鳗血清中t含量显著降低;而雌鳗血清17β-e2含量在埋植mt2次后显著升高.在雄鳗中,埋植adsd后第15天的血清t和17β-e2水平均显著升高,并随埋植次数的增加而增加;而埋植mt后第15天的血清t含量也显著升高,并随埋植次数的增加而增加,但血清17β-e2水平仅在埋植第3次后显著高于对照组.研究结果表明:埋植adsd和mt对日本鳗鲡血清t和17β-e2的影响存在明显的性别差异.
雄烯二酮和甲基睾酮诱导雌性日本鳗鲡性腺发育的反馈调节作用

水产学报 , 2000,
Abstract: 采用间隔15d多次埋植雄激素雄烯二酮(4-androstene-3,17-dine,adsd)或甲基睾酮(17a-methy-ltestosterone,mt)诱导雌性日本鳗鲡(anguillajaponica)性腺发育成熟;并着重研究埋植雄激素后,雌鳗血清中促性腺激素(gth)及脑和垂体中哺乳类促性腺激素释放激素(mgnrh)含量的动态变化。一次或多次埋植adsd后,1~5d的血清gth含量上升,然后下降;并且,血清gth含量上升的幅度随埋植次数的增加而增加;对于mt处理组,只在埋植7次后第15天测得血清gth水平显著高于对照组,但仍显著低于adsd处理组。这表明埋植adsd和mt可促进gth的分泌,但两者促进gth分泌的作用存在显著差异。埋植adsd1d后,脑和垂体中mgnrh含量明显增加,第2天后和对照组无明显差别,表明adsd促进了mgnrh的合成,并可能有一定程度的释放。研究表明雄激素对性腺未发育成熟的雌性日本鳗鲡在脑和垂体两个水平存在正反馈调节作用。
催化裂化水冷器管束泄漏分析及防护措施
,,,赵敏
腐蚀科学与防护技术 , 2012,
Abstract:
局部Lˉ一致空间中下半连续映射的不动点定理
,陈滋
四川师范大学学报(自然科学版) , 2008,
Abstract: 在没有任何线性结构的Lˉ空间证明了一个LˉKKM型定理,利用此LˉKKM型定理在Lˉ一致空间内对紧下半连续映射建立了一个新的几乎不动点定理,并进一步得到不动点定理.
抽象凸空间的广义向量平衡问题
,陈滋
四川师范大学学报(自然科学版) , 2010,
Abstract: 研究了抽象凸空间的几类广义多值向量平衡问题,通过分别应用抽象凸空间的不动点定理及极大元定理,证明了不同形式的广义向量平衡问题解的存在性
断层周围的弹塑性区及其地质意义
,
地球学报 , 2002,
Abstract: 采用弹塑性有限单元方法,通过模拟符合实际状况的逐步加载过程所引起应力场和塑性形变区的研究,得出如下结果:①在塑性或韧性剪切形变情况下,断裂或形变带的共轭剪切角往往大于45°;②在双向挤压应力条件下,先存断裂的前缘部位没有拉伸应力存在,但可能有伸展形变发生;③与最大主压应力夹角为30°~90°的断层前缘是偏应力的优势方位,容易发生塑性剪切形变,特别是夹角为60°左右的断层是最易发生新的构造活动的断层;④多数断层两侧一定范围内以及断层内部是相对的低应力区。这些应力的低值区,非常有利于矿液和油气的运移、聚集和成藏。
“铬渣山”周围人群的姐妹染色单体互换分析
吕慈,,金元
癌变·畸变·突变 , 1990,
Abstract:
肿痛宁熏洗剂治疗痔疮术后158例
,,
中国中医药信息杂志 , 2004,
Abstract:
井下管柱的真实轴向力计算与应用
Calculation and Application of Real Axial Force of Downhole Pipe String
 [PDF]

冯定, 王杰,, 孙巧雷, , 涂亿柳
Journal of Oil and Gas Technology (JOGT) , 2016, DOI: 10.12677/JOGT.2016.383027
Abstract:
管柱的摩阻计算精度直接关系到完井的质量。国内外学者已经建立了许多管柱摩阻计算模型,其中“刚杆模型”是较为常用的计算模型,但是该模型在计算管柱微元体所受的浮力时,没有考虑到微元体的端面不受液体的静压力,导致所计算的轴向力为有效轴向力。对于只有侧面与液体接触的管柱单元,如果仍把排开液体的重力作为浮力,此时会在管柱单元的两端产生附加轴向力,将在此基础上计算管柱的真实轴向力,得出新的计算公式,提高管柱摩阻的计算精度。为验证模型的准确性,同时采用现有的刚杆模型和笔者所建立的模型,利用Matlab编程求解某一实际井的注水管柱在上提时的受力情况,并将两个模型所求的结果进行比较,发现建立的模型计算结果显示管柱存在中性点,中性点以下受压,中性点以上受拉,该结果与管柱的实际受力情况相符。
The calculation precision of pipe string’s fraction was directly related to the quality of well com-pletion. Domestic and foreign scholars have established a lot of models to calculate the friction of pipe string, of which the “rigid rod model” was more frequently used, but the static pressure without liquid at ends of micro-unit was not taken into account when the buoyancy of pipe string on the unit is calculated, thus the calculation of axial force was the effective axial force. For the pipe string unit that only side is contacted with liquid, if the displaced fluid gravity is used as its buoyancy, additional axial force would be generated at the ends of the unit, the real axial force of pipe string is calculated based on the study above, a new calculation formula is established for improving the accuracy of calculation of pipe string friction. To verify the accuracy of the model, the existing rigid rod model and the model established in this paper are used to solve the stress of water injection string when it is lifted in a actual well, and Matlab program is used to solve it. By comparing the results of the two models, the results of the model of this paper show that the pipe string exists neutral point, the pipe string above the neutral point is subjected to tension and the pipe string below the neutral point is subjected to pressure, this result is closer to the actual stress state of pipe string.
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