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1.
In order to select an optimum extraction method for the target glycoprotein (TGP) from jellyfish (Rhopilema esculentum) oralarms, a high performance liquid chromatography (HPLC)–assay for the determination of the TGP was developed. Purified target glycoprotein was taken as a standard glycoprotein. The results showed that the calibration curves for peak area plotted against concentration for TGP were linear (r = 0.9984, y = 4.5895x+47.601) over concentrations ranging from 50 to 400 mgL-1. The mean extraction...  相似文献   

2.
精密和详细测定地球重力场及其时间变化,是目前卫星重力测量的主要课题。基于固体潮研究的最新成果,研究了固体潮对地球重力场时变特征的影响。不同于IERS2003采用的Cartwright和Tayler(1971)的引潮力位(TGP)展开,而是利用郗钦文的TGP展开,给出了固体潮对地球重力场时变特征影响的理论公式,并考虑到4阶潮汐的效应,精度可达到1011^-11ms^-2量级,同时采用最新的TGP展开数据重新计算了固体潮Love数相对频率特性对地球引力场的影响,并考虑了较多的潮波项,最后对重力数据归算中的永久性潮汐的处理进行了总结和说明。  相似文献   

3.
《山地科学学报》2020,17(1):203-215
Changes of cultivated land patterns caused by major water conservation projects are rarely reported. We selected the Three Gorges Reservoir area in China to study the change in area and landscape pattern of the cultivated land in the head,central, and tail areas of the reservoir that took place between 1992 and 2015; we then studied the spatial distribution of the cultivated land in the three parts of the reservoir; finally, we studied the driving forces behind the changes in the cultivated land. The results derived are as follows.(1) During the construction of the Three Gorges Project(TGP, 1992–2015), the area of cultivated land around the reservoir decreased by30.23 million ha. This reduction occurred in phases:the most severe change in cultivated land occurred during the later stage of the project(2002–2010);only 0.62 million ha of cultivated land did not change between 1992 and 2015.(2) Spatial pattern analysis showed that the cultivated land in the three parts of the reservoir changed from a northern distribution to a southern distribution; thus, the area of cultivated land in the north decreased over the time period. The area of cultivated land in the head and tail areas decreased by varying degrees, while it increased in the central area over the 23 years, indicating that the change in cultivated land showed regional differences.(3) The TGP, the policy of reverting farmland to forest,and urbanization were the main driving factors for the change of cultivated land, but there were differences in their impacts at different stages.(4) According to the patch dynamics of the land cover change, the degree of change gradually intensified during the early and later stages of the project and then stabilized during the operational period. Our research provides scientific support for the protection of cultivated land resources and food security in the reservoir area and for the coordination of social and economic development, which is of great significance to sustainable development in the reservoir area.  相似文献   

4.
基于谱-有限元法计算一个球型、非自转、完全弹性、各向同性(SNERI)的地球固体潮形变,其中地球固体部分潮汐形变的弱解用哈密顿变分原理给出,液核部分的弱解采用静态中性分层的流体近似。计算过程中把SNERI地球进行等间距球层剖分,球面上对解函数和试探函数采用球谐展开,径向上采用线性插值。比较数值计算结果与同质地球模型的解析解结果得出,1 km径向等距剖分即可获得10~(-8)精度量级的低阶Love数。基于PREM地球模型的计算结果表明,谱-有限元法计算的固体潮2~3阶Love数与Runge-Kutta法的计算值差异在10~(-4)量级;与武汉台超导重力仪8个主潮波的实测重力潮汐因子相比,本方法计算的理论重力潮汐因子相差平均约0.15%。研究结果说明,谱-有限元法具有较好的收敛性与较高的计算精度,比传统Runge-Kutta法更适用于高精度地计算复杂地球模型的固体潮形变。  相似文献   

5.
???????????????????????????Tzz????????Txx+Tyy??Tzz-Txx-Tyy???????????????????????????????????????????????в??????????????????????????????????????????????????????????????????????????????????????????????????????????Ч?????????????????????????????????????????????????????????????????????????????????????????????100?????????????????????????????????????????????????????????????????Ч??κ???????????????????????????????????Tzz-Txx-Tyy?????????????Tzz??Txx+Tyy??  相似文献   

6.
??20?????????????????????????????????????????μ??Σ???????????μ??о???????????·?????????????????о???????????????????о????????????δ????????о??????  相似文献   

7.
基于大同地震台的体应变数字化观测资料,利用功率谱密度估计方法,在没有对体应变资料进行任何改正情况下,准确获取了2011年3月11日日本9.0级大地震激发的0S4~0S37基频球型自由振荡.并与PREM模型理论自由振荡的周期进行对比分析,得出实测周期与PREM预测振荡周期相吻合,除0S10周期的相对误差为0.29%外,其余周期误差均小于0.1%.  相似文献   

8.
固体潮对测站位移影响的理论研究   总被引:3,自引:2,他引:1  
重新推导了IERS2 0 0 0中关于固体潮对测站位移影响的所有公式 ,指出 :在时间域内二阶和三阶引潮力位对测站位移影响的公式中 ,理论上应以测站地心距代替地球赤道半径。利用最新的精密引潮位展开代替IERS2 0 0 0采用的Cartwright&Tayler(1971)潮汐展开 ,重新计算了田谐潮波和带谐潮波的相对频率特性的改正。计算表明 ,以上两种修正在亚毫米量级上与IERS2 0 0 0存在差异 ,这在目前的空间大地测量技术中是必须考虑的。  相似文献   

9.
通过对《孔疏》标“兴”之特点与《毛诗传》《郑笺》标“兴”之特点比较分析,提出《孔疏》之标“兴”主要着眼于“兴”与作品主旨之间的关系,而没有特别注重标“兴”的位置。这些特点使得《孔疏》之“兴”开始从政治化逐渐转向文学化。  相似文献   

10.
本研究对地球起源与海陆成因及变迁等问题进行论证,以物质运动基本原理(物质集中、能量释放)提出:“地球中间膨胀(释能)造陆、大陆向两极移动”的新学说(1982年)。认为地球成因与演变同其它天体一样,是在星际物质集中下发生的能量释放过程。由于地球水分子多,能量释放缓慢亦使陆地生成缓慢,陆地是其后产生的。陆地主要生成在地球自转离心力、日月引力、地球张力(内能膨胀)的最强区。这样不仅使地球会演变成椭球体,同时膨胀区大陆在向两极方向移动中,便发生海陆变迁与地表形变。  相似文献   

11.
“数字地球”科学工程   总被引:10,自引:0,他引:10  
“数字地球”是集科学、技术和工程于一体的一项宏伟的科学体系。“数字地球”由基础研究、技术支撑和科学工程三部分组成,其中科学工程是“数字地球”的核心和目标。文章在我国“数字地球”科学工程现状分析的基础上,结合国情,对我国“数字地球”科学工程的发展提出了建议。  相似文献   

12.
数学、物理、化学、天文、生物等各个学科都有不少论文论述假说对其学科发展的贡献 ,但测绘科学方面与此有关的论文则不多见。以地扁说、地壳均衡学说、最小二乘法等为例的假说在测绘科学发展中具有一定的作用和意义。  相似文献   

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