含低价钨的双核化合物(Et_4N)_2[(CO)_4W(μ—S)_2MoS_2]和(Et_4N)_2[(CO)_4W(μ—S)_2WS_2]的合成及晶体结构

用新方法合成并测定了含W(O)的双核化合物(Et_4N)_2[(CO)_4W(μ—S)_2MoS_2](Ⅰ)和(Et_4N)_2[(CO)_4W(μ—S)_2WS_2)(Ⅱ)的晶体结构。Ⅰ和Ⅱ均属正交晶系,其空间群分别为PbCm和Pbam。Ⅰ的a=18.334(5),b=11.946(3),c=13.448(6),Z=4,R=0.057;Ⅱ的a=12.007(2),b=13.523(3),c=18.414(4),Z=4,R=0.058。Ⅰ和Ⅱ的阴离子均为以W(O)为中心的八面体和以Mo(Ⅵ)或(W)为中心的四面体共边且以μ—S连接,W(μ—S)_2M(M=Mo,W)共平面。其中W—Mo键距为2.964(3),W—W键距为3.0103(8),并发现其IR中M(O)—S_b键的ν在424.3～437.8cm~(-1)范围。     

Mn/W催化剂上甲烷氧化偶联反应机理的Monte Carlo模拟

通过对Mn-Na2WO4/SiO2催化剂的甲烷氧化偶联反应机理进行初步研究,以Mn/W双金属活性中心为基础,分析了CH4和O2共进料氧化偶联制C2烃的反应模型,并采用Monte Carlo方法对该反应的微观过程进行模拟,在与实验相近的条件下,得到了较准确的模拟结果.在模拟实验中,考察了活性位规模和原料气组成对反应结果的...     

LambertW函数性质及其应用

介绍了LambertW函数的代数及图像性质,如该函数的级数展开式、微分及函数在复平面的图像等。总结了其在数学、物理、化学和生物等领域的应用情况。     

北京正负电子对撞机方案的初步提出与确立

从1957年到1977年,中国高能物理加速器的设计方案历经了“六上六下”的波折.1977年11月第7次上马的高能质子加速器工程——“八七工程”在1980年底遭遇下马.在以张文裕为首的高能物理学家们的努力争取之下,经邓小平批准,保留和利用“八七工程”预制研究的余款,经过一番分外曲折的探寻,借助中美高能物理合作的有利条件,正确采纳李政道、潘诺夫斯基等人关于建造正负电子对撞机的建议方案,几经论证最终选定了中国高能加速器的建设方案——正负电子对撞机,奠定了中国高能物理在世界高能物理研究领域占据一席之地的基础.     

两种W火焰锅炉对燃烧无烟煤适应性的分析

本文较为详细地介绍了目前国内的两种主要流派W火焰锅炉,通过分析其燃烧器结构、配风方式、运行调整手段等技术特点,以及根据作者在国内电厂的调研结果,总结出何种炉型更能够适应燃烧劣质无烟煤,以供锅炉选型尤其是燃用超低挥发份劣质无烟煤锅炉的选型作为参考。     

Ernst Cassirer's transcendental account of mathematical reasoning

Cassirer's philosophical agenda revolved around what appears to be a paradoxical goal, that is, to reconcile the Kantian explanation of the possibility of knowledge with the conceptual changes of nineteenth and early twentieth-century science. This paper offers a new discussion of one way in which this paradox manifests itself in Cassirer's philosophy of mathematics. Cassirer articulated a unitary perspective on mathematics as an investigation of structures independently of the nature of individual objects making up those structures. However, this posed the problem of how to account for the applicability of abstract mathematical concepts to empirical reality. My suggestion is that Cassirer was able to address this problem by giving a transcendental account of mathematical reasoning, according to which the very formation of mathematical concepts provides an explanation of the extensibility of mathematical knowledge. In order to spell out what this argument entails, the first part of the paper considers how Cassirer positioned himself within the Marburg neo-Kantian debate over intellectual and sensible conditions of knowledge in 1902–1910. The second part compares what Cassirer says about mathematics in 1910 with some relevant examples of how structural procedures developed in nineteenth-century mathematics.     

基于5W模型的教育认同效果影响因素实证——以高校思想政治教育为例

基于传播学视角，借助5W模型，实证了高校思想政治教育传播过程中传播主体、传播内容、传播渠道、传播对象等因素对思想政治教育认同效果的影响.结果表明，传播者与接受者关系强度、传播者专业能力、传播对象专业能力、传播内容、传播媒介均对思想政治教育认同效果有显著的正向影响，且传播内容、传播媒介、传播者与接受者关系强度对当前高校思想政治教育认同效果的影响最大.因此，当前高校思想政治教育应着力创新并丰富传播内容，系统运用好现代社会化媒介，借助“课程思政”强化教育主体双方的关系，进而促进高校思想政治教育认同的效果.     

A specimen of Tirumala hamata hamata (Macleay, 1826) (Lepidoptera: Danainae) from Captain Cook’s first voyage

On 29 May 1770 Joseph Banks described a spectacular swarming of ‘milions’ [sic] ‘of one sort’ of butterfly at Thirsty Sound, near what is now Rockhampton, Queensland, comparing it to a species from China that had been named by Linnaeus. Discovery of what appears to be an Endeavour voyage specimen of this Australian butterfly in the Hunterian Zoology Museum, Glasgow, allows us to confirm its long-suspected identity as Tirumala hamata hamata (Macleay) – a species unnamed and unknown at the time of Cook’s first voyage. Investigations into several collections that include eighteenth-century Australian Lepidoptera and associated literature have not positively identified any further specimens taken from the swarm, although a pair in the Oxford University Museum of Natural History could be from the same source. Taxonomic confusion due to mimicry, convergence and/or non-divergence affecting blue tiger patterned butterflies is most likely the principal reason such a specimen has previously gone undetected.     

基于W和W-class态信道的概率性受控隐形传态

提出利用三粒子W和W-class态传送一个未知单粒子态从而实现受控量子隐形传态的方案。发送者Alice通过这种信道在Bob的控制下传送一个未知单粒子态给接受者Charlie。详细讨论了该方案,并给出了成功概率。     

离散W变换的一种推广

离散W变换(DWT)在数字信号、图像处理、频谱分析、数据压缩和信息隐藏等领域有着广泛的应用,DWT具有4种类型.文中推广了离散W变换,给出了一个包含3个参数的统一表达式,并证明在许多情形新变换是正交变换.