振兴东北老工业基地的体制思考

由厦门大学财政系提供的2003年国有资产监管体制与公共财政制度改革国际会议论文集15党的十六大报告中已明确提出：“支持东北地区等老工业基地加快调整和改造，支持以资源开采为主的城市和地区发展接续产业……” 这是我国中央政府首次提出振兴东北老工业基地的方略。加快东北老工业基地的调整、改造和振兴，对我国经济的发展有着重要而深远的意义：有利于促进地区经济的协调发展，有利于增强国民经济的活力和发展后劲，有利于提高我国产业和企业的国际竞争力。值得一提的是,由于东北老工业基地的国有经济比重偏高、市场发育不足的事实赋予了这次振兴东北老工业基地更为深远的意义，有利于推动我国国有经济的布局和结构，进一步推动我国国有资产管理体制的改革

First Sagittarius A* Event Horizon Telescope Results. VIII. Physical Interpretation of the Polarized Ring

In a companion paper, we present the first spatially resolved polarized image of Sagittarius A* on event horizon scales, captured using the Event Horizon Telescope, a global very long baseline interferometric array operating at a wavelength of 1.3 mm. Here we interpret this image using both simple analytic models and numerical general relativistic magnetohydrodynamic (GRMHD) simulations. The large spatially resolved linear polarization fraction (24%–28%, peaking at ∼40%) is the most stringent constraint on parameter space, disfavoring models that are too Faraday depolarized. Similar to our studies of M87*, polarimetric constraints reinforce a preference for GRMHD models with dynamically important magnetic fields. Although the spiral morphology of the polarization pattern is known to constrain the spin and inclination angle, the time-variable rotation measure (RM) of Sgr A* (equivalent to ≈46° ± 12° rotation at 228 GHz) limits its present utility as a constraint. If we attribute the RM to internal Faraday rotation, then the motion of accreting material is inferred to be counterclockwise, contrary to inferences based on historical polarized flares, and no model satisfies all polarimetric and total intensity constraints. On the other hand, if we attribute the mean RM to an external Faraday screen, then the motion of accreting material is inferred to be clockwise, and one model passes all applied total intensity and polarimetric constraints: a model with strong magnetic fields, a spin parameter of 0.94, and an inclination of 150°. We discuss how future 345 GHz and dynamical imaging will mitigate our present uncertainties and provide additional constraints on the black hole and its accretion flow

控制钨粉粒度的工业实验

一、前言钨制品的深度加工,要求有高质量的钨粉。运用电子计算机控制钨粉生产,不仅可以保证产品质量和提高劳动生产率,而且可以得到预期产品和再现性。通过微机控制蓝钨五段还原炉的温度、氢气流量、推舟速度等三个主要还原参量,达到了稳定生产的目的。为了获得合格的 W31钨粉,必须在此基础上寻找最佳工艺条件。W31钨粉的生产取决于工艺条件和原料的性质。各批原料的性质可能存在着波动,因此每批原料应该进行试探实验,寻找该批料还原生产 W31钨粉的最佳工艺条件。W31钨粉是由 W31D 粉和 W31B 粉混合而成,W31B 粉的工艺条件不宜改变,所以必须对 W31D 粉生产的工艺条件进行研究。本实验就是利用微机控制系统,寻找蓝钨还原制取 W31D 粉的最佳工艺条件

控制钨粉粒度的工业实验

一、前言钨制品的深度加工,要求有高质量的钨粉。运用电子计算机控制钨粉生产,不仅可以保证产品质量和提高劳动生产率,而且可以得到预期产品和再现性。通过微机控制蓝钨五段还原炉的温度、氢气流量、推舟速度等三个主要还原参量,达到了稳定生产的目的。为了获得合格的 W31钨粉,必须在此基础上寻找最佳工艺条件。W31钨粉的生产取决于工艺条件和原料的性质。各批原料的性质可能存在着波动,因此每批原料应该进行试探实验,寻找该批料还原生产 W31钨粉的最佳工艺条件。W31钨粉是由 W31D 粉和 W31B 粉混合而成,W31B 粉的工艺条件不宜改变,所以必须对 W31D 粉生产的工艺条件进行研究。本实验就是利用微机控制系统,寻找蓝钨还原制取 W31D 粉的最佳工艺条件

Response of serine/threonine protein kinase SpkC to high temperature stress in Synechocystis sp. PCC 6803

Serine/threonine protein kinases play important roles to sense and transduce signal to cope with external environment. However, functions of many serine/threonine protein kinases in cyanobacteria are still unknown. [Objective] This study aims to explore whether SpkC in Synechocystis sp. PCC 6803 responses to high temperature stress. [Methods] We used the homologous recombination method to construct the spkC gene knockout mutant (ΔspkC), and then compared the growth rate, pigment contents of ΔspkC mutant and the wild strain under high temperature stress. In addition, we detected chlorophyll fluorescence under high temperature stress. Recoveries of ΔspkC and wild strain from high-temperature stress were determined through measuring the growth rate under normal temperature. [Results] Compared with wild type strain, ΔspkC mutant grew slower, and the contents of three photosynthetic pigments (chlorophyll, carotenoid and phycobilin) decreased after high temperature stress at 42 °C. The activity of photosynthetic system II in ΔspkC decreased more rapidly at 45 °C. What's more, ΔspkC strain was not able to recover after high-temperature stress for 5 days; their survival rate was significantly lower than wild-type. [Conclusion] The deletion of spkC led to severe defect response to high-temperature stress in Synechocystis sp. PCC 6803, which suggests that serine/threonine protein kinase SpkC is involved in response processes against high temperature stress

天山北部沙漠－绿洲－冰雪带的水热循环与环境效应研究

该项目利用树木年轮重建了天山中段北坡370年的降水日数序列,分析了树木年轮与非常规积温的关系。项目揭示了新疆极端降水的变化和空间分布差异,得出天山南北麓绿洲的冬、夏和年极端降水量都有不同程度的增多趋势,年极端降水量于1980年发生了突变。在天山北坡四工河流域绿洲—沙漠交界处进行了野外大气观测实验,研究了天山北坡中部经向剖面上的沙漠—绿洲—高山冰雪气候带气候变化随高度的响应,在各个高度上,冬季增温幅度都要大于夏季;在沙漠的低海拔地区,年降水量增加幅度并不是最大的,而在海拔较高的山前绿洲地带和在3500m的高山区降水量增幅相对较大。项目研究发现隆冬时期低纬系统异常活跃,在一定的大气环流条件下,阿拉..

Preparation and Characterization of MnO/TiN Anode for Lithium Ion Batteries

以乙酸锰和钛酸四丁酯为原料，柠檬酸为络合剂，采用溶胶-凝胶法制备钛酸锰（MnTiO3）粉体，而后将其粉体高温氨气氮化，可得到MnO/TiN复合材料. 使用X射线衍射（XRD）、X射线能量色散谱（EDS）和场发射扫描电子显微镜（FESEM）表征材料的物相结构与组分、观察其形貌. 采用循环伏安、恒流充放电和电化学阻抗方法测试电极电化学性能. 结果表明，MnO/TiN电极在100 mA?g-1和1 A?g-1倍率放电下，比容量分别为394 mAh?g-1和146 mAh?g-1，均高于单纯MnO电极比容量和倍率性能，这归因于复合材料中的TiN提供了导电网络，并有效地抑制了电极在充放电过程中的体积膨胀效应.Manganese titanate (MnTiO3) powder was prepared via a sol-gel method using manganese acetate and tetrabutyl titanate as raw materials, and citric acid as a chelating agent. Through high temperature nitridation of MnTiO3 powder in ammonia, the MnO/TiN composite was obtained. The phase structure, composition and morphology of the composites were characterized by XRD, SEM and EDS. The electrochemical properties of the composite electrodes were studied by performing cyclic voltammetry, galvanostatic charge and discharge, and electrochemical impedance spectroscopy tests. The MnO/TiN electrode delivered specific capacities of 394 mAh?g-1 and 146 mAh?g-1 at the current density of 100 mA?g-1 and 1 A?g-1, respectively, and exhibited higher specific capacity and superior rate capability than MnO electrode, which can be ascribed to the presence of TiN in the composite offering an electron conducting network and suppressing the volume expansion of MnO efficiently during the charge and discharge processes.科技部重大研究计划（973 项目，No. MOST2011CB935700）、中科院“百人计划”和山东省杰出青年基金（No. BS2009NJ013）、国家自然科学基金项目（No. 20971077）资助作者联系地址：1.中国海洋大学化学化工学院，山东 青岛 266100； 2.中国科学院青岛生物能源与过程研究所，山东 青岛 266101Author's Address: 1. College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, Shandong, China; 2. Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, Shandong, China通讯作者E-mail：[email protected]; [email protected]