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171.
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本研究以硫酸镁作为麻醉剂,比较了在不同水温条件下硫酸镁对仿刺参幼参的麻醉效果,分析了不同浓度硫酸镁对仿刺参幼参的麻醉效果。实验水温设置11℃、13℃、15℃、17℃、19℃和21℃六个温度梯度,实验用仿刺参幼参规格分为大规格(L)40.26±1.84g、中规格(M)21.83±1.72g、小规格(S)11.03±1.63g。实验结果显示:1.在硫酸镁麻醉剂浓度相同时,仿刺参规格越大麻醉所需时间越长,复苏时间却越短;随着麻醉剂浓度增加,对仿刺参幼参麻醉时间相应缩短,但复苏时间呈现逐渐延长。不同浓度硫酸镁麻醉剂对不同规格仿刺参的麻醉效果具有显著差异(P0.05)。2.在水温11℃~20℃范围内,随着水温的升高,对仿刺参幼参的麻醉时间从26.13±17.78min缩短到21.47±3.52min,但复苏时间从26.13±17.78min增加到71.05±12.32min,不同水温条件下硫酸镁对仿刺参幼参麻醉效果影响显著(P0.05)。研究表明,仿刺参体重在20g以下的适宜麻醉浓度为0.1~0.25mol·L-1,体重在20g以上的适宜麻醉浓度为0.25~0.35mol·L~(-1)。 相似文献
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碳酸铷、硼酸化学计量比混合,蒸发溶液,直至五硼酸铷RbB5O8·4H2O晶体析出。经粉末X射线衍射(XRD)、拉曼光谱(Raman spectroscopy)、热重/微商热重/差示扫描量热(TG/DTG/DSC)、原子吸收光谱等实验方法,确定其化学组成及结构。298.15、333.15K时测量溶液的物理化学性质(密度、电导、pH),并与经验方程进行拟合,研究五硼酸铷溶液的物化性质随浓度、温度的变化规律。根据文献报道的平衡常数,实验测量的pH数据,采用牛顿迭代法进一步研究五硼酸铷溶液中主要存在的硼酸根离子对类型、含量以及物种的形成。 相似文献
174.
Hongrun Ju Lijun Zuo Jinfeng Wang Shengrui Zhang Xiao Wang 《International journal of geographical information science》2016,30(11):2188-2207
Scientific interpretation of the driving forces of built-up land expansion is essential to urban planning and policy-making. In general, built-up land expansion results from the interactions of different factors, and thus, understanding the combined impacts of built-up land expansion is beneficial. However, previous studies have primarily been concerned with the separate effect of each driver, rather than the interactions between the drivers. Using the built-up land expansion in Beijing from 2000 to 2010 as a study case, this research aims to fill this gap. A spatial statistical method, named the geographical detector, was used to investigate the effects of physical and socioeconomic factors. The effects of policy factors were also explored using physical and socioeconomic factors as proxies. The results showed that the modifiable areal unit problem existed in the geographical detector, and 4000 m might be the optimal scale for the classification performed in this study. At this scale, the interactions between most factors enhanced each other, which indicated that the interactions had greater effects on the built-up land expansion than any single factor. In addition, two pairs of nonlinear enhancement, the greatest enhancement type, were found between the distance to rivers and two socioeconomic factors: the total investment in fixed assets and GDP. Moreover, it was found that the urban plans, environmental protection policies and major events had a great impact on built-up land expansion. The findings of this study verify that the geographical detector is applicable in analysing the driving forces of built-up land expansion. This study also offers a new perspective in researching the interactions between different drivers. 相似文献
175.
金翅岭金矿是胶东招远北部的一个典型石英脉型金矿,构造是金矿最为重要的控矿因素。在前人资料的基础上,综合分析了矿区构造控矿特征,总结了构造控矿规律:矿脉分支复合,表现为NE向矿脉产生SN,NNE向次级矿脉,NNE向矿脉产生NE向次级矿脉;矿体厚度与金品位呈负相关,深部次级矿脉群在P4脉下盘出现;矿脉侧伏角和倾伏向变化处矿体富集,表现为SW向侧伏的P4矿脉,矿体富集于-240 m,侧伏角变大,同时倾伏向由SW向转变为NW向的部位。最后建立了平面和剖面P4矿脉的波形函数,并对深部进行了预测。 相似文献
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Seed long-distance dispersal(LDD) events are typically rare, but are important in the population processes that determine large-scale forest changes and the persistence of species in fragmented landscapes. However, previous studies focused on species dispersed via animal-mediated LDD, and ignored those dispersed by wind. The aim of this study was to assess the effects of canopy openness, edge, seed source, and patch tree density on the LDD of seeds by wind in forest. We collected birch seeds, a typical wind-dispersed species, throughout a larch plantation. We then assessed the relationship between birch LDD and each factor that may influence LDD of seeds by wind including distance to edge, canopy openness size, distance to mature forest, and the tree density of the larch plantation. We used univariate linear regression analysis to assess the influence of those factors on birch LDD, and partial correlations to calculate the contribution of each factor to LDD. The results showed that both canopy openness and edge had significant influences on birch LDD. Specifically, a negative relationship was observed between distance to edge and birch LDD, whereas there was a positive correlation between canopy openness size and LDD. In contrast, the distance to the mature forest was not correlated with birch LDD. Our results suggest that patch tree density could potently affect the probability of LDD by wind vectors, which provides novel and revealing insights regarding the effect of fragmentation on wind dynamics. The data also provide compelling evidence for the previously undocumented effect of habitat fragmentation on wind-dispersed organisms. As such, these observations will facilitate reasonable conservation planning, which requires a detailed understanding of the mechanisms by which patch properties hamper the delivery of seeds of wind-dispersed plants to fragmented areas. 相似文献