极大螺旋藻铁型超氧物歧化酶的纯化及性质

极大螺旋藻 Ｓｐｉｒｕｌｉｎａｍａｘｉｍａ藻体ＳＯＤ聚丙烯酰胺梯度凝胶电泳呈现４条同工 酶带, Ｈ_ ２Ｏ_２明显抑制该酶活性, ＫＣＮ对酶活性无影响,确认为 Ｆｅ－ＳＯＤ经硫酸铵分部盐析、离子交 换柱层析及凝胶过滤,纯化到电泳单斑点均－程度．纯化的Ｆｅ－ＳＯＤ分子量为３９．３ＫＤ,亚基分子 量为２０ＫＤ金属元素分析表明,每个亚基含０ ５５个Ｆｅ原子,该酶在紫外区最大吸收峰值为 ２７５．８nｍ、该酶氨基酸组成与蓝、绿藻和高等植物的Ｆｅ－ＳＯＤ相似,但它含有较高的丙氨酸,酸性氨 基酸和碱性氨基酸比值与低等植物及原核生物相近而明显高于高等植物．     

阿尔金断裂花海段新生代变形特征及时间

在地表地质调查并结合钻井资料分析的基础上,主要通过地震剖面的精细地质解释,对阿尔金断裂东段的构造变形特征进行了系统分析。认为阿尔金断裂经阿克塞至肃北向北东东方向延伸,既没有止于玉门市西北的宽台山,也没有延伸至金塔盆地,而是止于其间的花海盆地花探7井东侧。阿尔金断裂花海段的变形时间主要为渐新世晚期、上新世末期和晚更新世末,以后者最为强烈。与红柳峡段的对比说明变形强度自西向东逐渐减弱,变形方式主要为走滑兼逆冲,主要构造样式为半花状构造,并派生有一系列向南西西方向收敛的弧形断裂。     

Improvement of photorefractive properties in Hf:Fe:LiNbO3 crystals with various [Li]/[Nb] ratios

Photorefractive properties of Hf:Fe:LiNbO₃ crystals with various [Li]/[Nb] ratios have been investigated at 488 nm wavelength based on the two-wave coupling experiment. High diffraction efficiency and large recording sensitivity are observed and explained. The decrease in Li vacancies is suggested to be the main contributor to the increase in the photoconductivity and subsequently to the induction of the improvement of recording sensitivity. The saturation diffraction efficiency is measured up to 80.2%, and simultaneously the recording sensitivity of 0.91 cm/J is achieved to in the Hf:Fe:LiNbO₃ crystal grown from the melt with the [Li]/[Nb] ratio of 1.20, which is significantly enhanced as compared with those of the Hf:Fe:LiNbO₃ crystal with the [Li]/[Nb] ratio of 0.94 in melt under the same experimental conditions. Experimental results definitely show that increasing the [Li]/[Nb] ratio in crystal is an effective method for Hf:Fe:LiNbO₃ crystal to improve its photorefractive properties.     

高铁开通对县级单元产业结构的影响————以长三角地区为例

运用多期双重差分模型估计高铁开通对长三角地区县级单元产业结构的影响,并借助门槛效应和中介模型检验高铁效应的作用机制。结果显示：① 高铁开通显著促进了县级单元的产业结构升级,非同步地推动第二产业的分散和第三产业的聚集。② 人口规模对高铁效应存在部分中介作用,但在长三角县级单元中未发生门槛突变。③ 高铁开通对第三产业和第二产业的影响呈现不同的时间滞后性,致使县级单元产业结构转型存在两个窗口期,分别为开通当年和第3年。因此县级单元应立足自身情况并顺应高铁开通后的产业演化规律,以制定针对性的政策来激励或对冲。     

华北地台东部寒武系层序地层年代格架

北地台寒武系属稳定的克拉通盆地陆表海沉积。其沉积层序表现为复合层序，主要受全球海平面变化和沉积物补给因素的控制。自下而上可划分为１７个正层序，归并为６个正层序组和２个中层序。大部分正层序的边界与生物地层单位一致，与岩石地层单位略有出入。每个正层序的平均时间延续约为３Ｍａ，含两个三叶虫化石带。根据层序地层的研究，可以建立华北寒武系层序地层年代格架，并提出各统和阶的界线参考年龄。     

应用多普勒天气雷达资料分析强对流天气的垂直廓线特征

利用石家庄多普勒天气雷达资料,对2004-2007年的22次冰雹和39次短时强降水天气过程中的各要素进行了对比分析.结果表明:在单体对流云和积层混合型对流云中,冰雹回波的强度、高度均强(高)于短时强降水,并且单体对流云型冰雹和短时强降水的回波强度和顶高均强(高)于积层混合型,积层混合型对流云出现短时强降水比例高于冰雹.在回波中层,短时强降水主要为偏东风和偏南风,冰雹主要为偏西风、偏北风;冰雹平均风速大于短时强降水,在3～6 km的高度风速显著增加.强对流天气出现前均呈现低层辐合,高层辐散;都有较强的上升运动,在天气过程出现后冰雹的下沉运动更强;当高层辐散量大于低层辐合量时,对流云发展加强,反之减弱.     

3D Step-by-step inversion strategy for audio magnetotellurics data based on unstructured mesh

A three-dimensional (3D) step-by-step inversion strategy for audio magnetotellurics(AMT) is investigated in this study.The objective function is minimized by it...     

Numerical Simulation on Coseismic Effect of the November 14,2001 Great Kunlun Earthquake,Northern Tibet,China

The November 14, 2001 Ms8.1 Kunlun Mountains earthquake in northern Tibet is the largest earthquake occurring on the Chinese mainland since 1950. We apply a three-dimensional （3-D） finite element numerical procedure to model the coseismic displacement and stress fields of the earthquake based on field investigations. We then further investigate the stress interaction between the Ms8.1 earthquake and the intensive aftershocks. Our primary calculation shows that the coseismic displacement field is centralized around the east Kunlun fault zone. And the attenuation of coseismic displacements on the south side of Kunlun fault zone is larger than that on the north side. The calculated coseismic stress field also indicates that the calculated maximal shear stress field is centralized around the east Kunlun fault zone; the directions of the coseismic major principal stress are opposite to that of the background crustal stress field of the Qinghai-Xizang （Tibet） Plateau. It indicates that the earthquake relaxes the crustal stress state in the Qinghai-Xizang （Tibet） Plateau. Finally, we study the stress interaction between Ms8.1 earthquake and its intensive aftershocks. The calculated Coulomb stress changes of the Ms8.1 great earthquake are in favor of triggering 4 aftershocks.     

对临汾人工影响天气工作的调研报告

人工增雨防雹是直接为工农业生产服务的公益性事业,有利于促进草木植被生长,可有效地扑救森林、草场火灾,是保护和改善生态环境的重要措施;可以减轻大气污染程度,改善空气质量,有益于人们的身心健康;可以缓解工业、农业和人民生活用水供需矛盾,促进社会经济可持续发展。分析表明,凡是降水量明显偏少的年份,粮食大都减产;年降雨量多的年份,粮食大都增产。这表明,人工增雨消雹对于经济建设和社会发展尤其是对农业生产有着重要的意义。     

SPOT5卫星影像在矿山环境调查中的应用

以吉林省辽源市煤炭矿山为研究对象,通过对SPOT5卫星影像纠正、融合、解译等处理,快速、便捷地查清矿区的地质环境问题:矿区固体废物堆放、尾矿库分布情况;矿山采空区地面塌陷、山体开裂、滑坡、崩塌、泥石流、岩溶塌陷、煤田自燃等地质灾害分布情况;由矿产开发引发的水土流失、土地沙化、侵占土地、植被破坏的情况;矿区水体、植被、土壤污染状况等。通过矿山地质环境调查实践,总结出了SPOT5卫星影像最优波段组合、融合方法及矿山地质环境调查中的地物判读标志,从而使SPOT5卫星影像在遥感环境地质调查中发挥了重要作用。