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251.
近年来,莘县国土资源局认真贯彻中央提出的关于加强党的先进性建设,树立和落实科学发展观,加强文明机关和新型机关建设,促进文明机关和新型机关建设相互促进和谐发展。自2004年以来连续3年被评为市级文明机关,被山东省国土资源厅授予模范先进集体,为构建和谐莘县,实现莘县经济的又好又快发展发挥着积极的作用。  相似文献   
252.
Reversible protein phosphorylation, catalyzed by protein kinases and phosphatases, is an important and versatile mechanism by which eukaryotic cells regulate almost all the signaling processes. Protein phosphatase 1 (PP1) is the first and well-characterized member of the protein serine/threonine phosphatase family. In the present study, a full-length cDNA encoding the beta isoform of the catalytic subunit of protein phosphatase l(PPlcb), was for the first time isolated and sequenced from the skin tissue of flatfish turbot Scophthalmus maximus, designated SmPPlcb, by the rapid amplification of cDNA ends (RACE) technique. The cDNA sequence of SmPPlcb we obtained contains a 984 bp open reading frame (ORF), flanked by a complete 39 bp 5' untranslated region and 462 bp 3' untranslated region. The ORF encodes a putative 327 amino acid protein, and the N-terminal section of this protein is highly acidic, Met-Ala-Glu-Gly-Glu-Leu-Asp-Val-Asp, a common feature for PP1 catalytic subunit but absent in protein phosphatase 2B (PP2B). And its calculated molecular mass is 37 193 Da and pI 5.8. Sequence analysis indicated that, SmPPlcb is extremely conserved in both amino acid and nucleotide acid levels compared with the PPlcb of other vertebrates and invertebrates, and its Kozak motif contained in the 5'UTR around ATG start codon is GXXAXXGXXATGG, which is different from mammalian in two positions A6 and G3, indicating the possibility of different initiation of translation in turbot, and also the 3'UTR of SmPPlcb is highly diverse in the sequence similarity and length compared with other animals, especially zebraf'lsh. The cloning and sequencing of SmPPlcb gene lays a good foundation for the future work on the biological functions of PP1 in the flatfish turbot.  相似文献   
253.
The landscape pattern of Da'an County, Northeast China has undergone significant changes since the 1950s as a result of climatic change and human activities. The aim of this paper is to quantitatively study landscape pattern and its spatial dynamics of Da'an County at the landscape level over the nearly 50-year span. Patch dynamics were examined according to land use and land cover change processes built from a series of images, as well as topographic maps, and temporal patterns built from landscape pattern metrics. The transition matrix of landscape patch types and changes of various landscape metrics were applied. The results showed that, from 1956 to 2000, the landscape within the study area had undertaken a complicated evolution in landscape structure and composition. The outstanding characteristic is that saline-alkali land increased and grassland decreased. As some smaller patches amalgamated, the heterogeneity of patch decreased. All those changes were the synthetic result of both climatic and anthropogenic influences, but the predominant factor was different in different parts. In the southern part of the study area, the landscape pattern changes resulted from the modification of climate obviously, while in the northern part, the landscape pattern changes were mainly caused by human activities, such as the conversion between farmland and saline-alkali land. This phenomenon showed that human activities played more important role in the north than in the south of Da'an County.  相似文献   
254.
基于模糊控制的快速循迹智能车的设计与实现   总被引:1,自引:0,他引:1  
提出基于模糊控制的快速循迹智能车的实现方法.利用转速传感器、线阵CCD、舵机等构成一个闭环控制系统,并采用PI算法控制智能车后轮速度.采用模糊控制算法将线阵CCD返回的误差模糊化,然后按照MAX-MIN规则进行逻辑推理,最后将推理结果反模糊化后以控制舵机转向.实验结果证明了该方法的有效性.  相似文献   
255.
���������ϲ��α������Ĺ�ϵ   总被引:1,自引:0,他引:1  
?????????????????????????1985??2006?????????????????????α??????????????????????????????????????????????????????????6???????????????????????????????????????????????????????л??????????????5??????????????????  相似文献   
256.
??TOPEX/Poseidon????????????Χ???????ν??з??????ó?????:?????????????Χ???????????ε?????;????????????????????ζ??????????,?????????????????????????????????????????????  相似文献   
257.
��³������ִ��������о�   总被引:3,自引:3,他引:0  
????????1956??1999??????????????????????????顢?????顢?????????????????????????????б??????е??????Щ???????????????4??????У?1956??1978????????????????????????????????ε????Ms7.4?????????????й??1978??1985???1990??1995?????????????????????????鶫??????Ms6.2 ??Ms6.1?????й??  相似文献   
258.
The isotherms of the interaction between the suspended particles and Cu2+, and the effects of lysine and asparaginic acid on the isotherms in the Huanghe (Yellow) River were studied by applying the theory and method of interfacial stepwise ion/coordination particle exchange. We obtained a new stepped river isotherm, formed by two curves joined together with a “plateau” in the middle. The adsorption equilibrium constantsK 1 andK 2 were calculated by using the isothermal equation of surface stepwise ion exchange. Amino acid in small amount promotes exchange adsorption of the suspended particles with Cu2+. The degree of promotive action relates to the isoelectric point of amino acid. The promotive effect of lysine is bigger than that of asparaginic acid. Project 29361001 supported by NSFC.  相似文献   
259.
该文是对测绘技术进步对经济发展的作用进行定量分析,并运用经济、数学、统计等科学方法,依据产出增长数学方程,对测绘生产单位产值增长、技术进步速度和水平等进行测算,预测2010年测绘生产发展规模、技术水平等,提出对策建议,供管理决策者及部门参考。  相似文献   
260.
The distribution of Oil & gas fields shows their close relationship with the most active tectonic regions. This is not a coincidence but having a scientific reasons. The crustal active regions, refer to the places where the active natural earthquake, volcanic activities, underground water happened, and the areas of the leaking off of natural gas to the surface of the crust. The magma of volcanic activities brings the organic "kitchen range body" hydrocarbon- generating model and inorganic genetic hydrocarbon to the regions covered by volcanic rock. Underground water brings a catalytic hydrocarbongenerating model for organic matter, and the leaking- off of H2 and CO2 contributes a synthetic hydrocarbon - generating model. Volcanic activities bring the assemblage of Source, Reservoir and Seal formed by the sediments and magma the sedimentary basins, and the hydrocarbon - generating system with a "water - volcano" binary structure is formed. All these conditions are favorable and excellent for the formation of oil & gas fields. The distribution of American oil & gas fields have very close relationship with the mines of Fe, Mn, Ct, Mo, W and V, deposits of Zn, Cu, V, Pb, Al and Hg, and the deposits of fluorite, sulfur, potassium salt, phosphate and halite, and the distribution of sulfate- chloride of river water. The reason why few oil & gas fields discovered in the regions covered by volcanic rock in western America maybe because of the view of "inconsistency between petroleum and volcano". Further more, It's very difficult to carry out a geophysical exploration in such kinds of regions.This paper examined a few hydrocarbon-generating models (systems) mentioned above and came up with some fresh ideas on the exploration in the areas covered with volcanic rocks.  相似文献   
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