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A three-dimensional(3D) coordination polymer {[Co(bdc)(dpb)]·H2O}n(1) was prepared by solvothermal reaction of 1,3-dipyridyl benzene(dpb) with deprotonated 1,3-benzenedicarboxylate(H2bdc), and was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group C2/c with a = 15.478(6), b = 12.865(5), c = 24.091(10) ?, β = 95.599(5)°, V = 4774(3) ?3, C24H18CoN2O5, Mr = 473.34, Dc = 1.267 g/cm3, F(000) = 1864.0, μ = 0.748 mm-1 and Z = 8. Each Co(II) ion links three bdc2- anions to form an infinitely 1D ladder-shaped chain containing binuclear [(COO)Co]2 cluster, and dpb links adjacent 1D chains to form a 3D pcu framework. In addition, the UV-vis of 1 was also studied. 相似文献
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采用退火后处理的方法,使SiOx∶H(0<x<2)形成纳米硅与二氧化硅的镶嵌结构.利用红外透射谱、Raman谱和光致发光谱,系统地研究了不同退火温度对薄膜微结构及室温光致发光谱的影响.发现发光谱均由两个Gauss线组成,其中主峰随着退火温度的升高而红移,而位于835nm的伴峰不变.指出退火前在720—610nm的波长范围内强的主峰可能来源于膜中的非晶硅原子团,随退火温度的升高主峰的红移是由于非晶硅原子团的长大.而伴峰可能来自硅过剩或氧欠缺引入的某种发光缺陷.1170℃退火后在850nm附近出现强的谱带与纳米硅的析出有关,支持了量子限制效应发光模型. 相似文献
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2005-2014年,IUPAC发表了一系列技术报告(Technical Reports)和建议(Recommendations)等.这些文献对化学领域的众多定义、命名、规则、标准、方法等进行了修订和补充,并推荐给全世界的化学工作者采用.高校教师要关注IUPAC发布的“新规”,在教学中积极传播IUPAC“新规”,在科研中积极采用和实践这些“新规”,以增强教学和科研的科学性、先进性和时代性.同时还应尽快实现由IUPAC“新规”的“跟随者”向“制定者”的身份转变,以促进我国化学教学和科研与时俱进. 相似文献
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Solvothermal reactions of 4,4'-oxybis(benzoic acid) (H2oba) with 1,3-dipyridyl benzene (1,3-dpb) produced a two-dimensional (2D) cadmium(Ⅱ) coordination polymer {[Cd(oba)(dpb)]·H2O}n (1). The complex was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group C2/c with a = 13.6692(9), b = 25.9647(17), c = 8.7912(6) , α = 125.0370(10), γ = 2544.7(3)°, V = 2544.7(3) 3, C30H22N2O6Cd, Mr = 618.91, Dc =1.609 g/cm3, F(000) = 1248, μ = 0.904 mm-1 and Z = 4. The neighboring Cd(Ⅱ) ions are linked by oba2-anions and 1,3-dpb to form an infinitely 2D wavelike sheet, and two such 2D sheets are interlocked with each other by H-bonding to form a 2D → 2D structure. The adjacent two groups of interlocked structures are further linked to form a bilayer 2D supramolecular network by π-π interactions. In addition, the fluorescence property of 1 was also studied. 相似文献
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最大偏心圆环空间自然对流传热的数值分析 总被引:2,自引:0,他引:2
采用正切圆坐标变换 ,对不同直径比以及上、下、侧面三种偏心位置 ,偏心率达到最大值± 1的变壁温水平圆柱环形封闭空间内空气的自然对流传热进行了数学模拟 ,求出的二维空间温度分布与实验拍摄相应的温度干涉条纹图片吻合良好。计算结果同时给出流线分布及内、外壁面的局部传热系数、热流量。并与现有的偏心率小于 1的有关资料作对比分析。数值计算的范围是 :2 .0× 1 0 2 ≤ Ra≤ 3 .0× 1 0 5,1 .3≤ Do/Di≤ 3 .8,Pr=0 .70 6,|ε|=1 . 相似文献
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A two-dimensional(2D)coordination polymer{[Cd(bdc)(dpb)]·H2O}n(1)has been prepared by solvothermal reaction of 1,3-dipyridyl benzene(1,3-dpb)with deprotonated1,4-benzenedicarboxylate(H2bdc),and was characterized by elemental analysis,IR spectroscopy,and X-ray single-crystal diffraction.It crystallizes in the monoclinic system,space group C2/c with a=15.1839(12),b=20.7585(17),c=7.2989(6),β=117.3450(10)°,V=2043.5(3)3,C24H18N2O5Cd,Mr=526.81,Dc=1.712 g/cm3,F(000)=1056.0,μ=1.110 mm-1and Z=4.The neighboring Cd(II)ions link the bdc2-anions and 1,3-dpb to form an infinite 2D sheet,and such two2D sheets are interlocked with each other to form a 2D→2D sheet.Two groups of interlocked sheets are further linked together by intermolecularπ···πinteraction,giving a 3D supramolecular network.In addition,the fluorescence property of 1 was also studied. 相似文献
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以两种V型的配体4,4’-二吡啶基苯(1,3-dpb)和4,4’-二羧基二苯砜(H2sdb),和钴(Ⅱ)通过溶剂热反应合成了1个配位聚合物{[Co(dpb)(sdb)(H2O)2]·2H2O·DMF}n(1)。对其进行了红外、热重、粉晶衍射、单晶衍射等表征,配合物属于三斜晶系,空间群P1。其中Co(Ⅱ)的2个顶点被水分子占据,相邻的钴(Ⅱ)离子连接着1,3-二吡啶基苯和4,4’-二羧基二苯砜形成一维的双绳链,相邻的链之间通过羧基-配位水和配位水-配位水间的氢键相互连接形成二维的层状结构,层状结构之间通过砜基-配位水间的氢键又相互连接形成三维结构。此外,还研究了配合物的固体紫外-可见光谱。 相似文献