Syntheses and Crystal Structures of Homleptic Lanthanide Complexes [C_6H_5COCHC(CH_3)N-(p-ClC_6H_4)]_3Ln(THF)_n (Ln =Yb,Y,Nd)

Three homoleptic lanthanide complexes, [C6H5COCHC(CH3)N(p-ClC6H4)]3Ln(THF)n(n = 0, Ln = Yb(1); n = 0, Ln = Y(2); n = 1, Ln = Nd(3)), were synthesized by amine elimination reaction of Ln[N(SiMe3)2]3 with 1-phenyl-3-N-(p-chlorophenylimino)-1-butanone. These complexes crystallize in triclinic, space group P1 with a = 9.805(3), b = 14.831(6), c = 16.075(6) A, α = 111.996(9), β = 91.570(7), γ = 93.744(6)°, V = 2159.4(13) A3, Z = 2, D3 c = 1.515 g/cm, F(000) = 986, μ(MoKα) = 2.396 mm-1, R = 0.0360 and wR = 0.0850 for 9548 observed reflections with I 2σ(I) for complex 1; a = 9.861(5), b = 14.852(9), c = 16.111(9) A, α = 112.362(13), β = 91.949(11), γ = 93.678(14)°, V = 2173(2) A3, Z = 2, Dc = 1.377 g/cm3, F(000) = 924, μ(MoKα) = 1.570 mm-1, R = 0.0735 and wR = 0.1389 for 8015 observed reflections with I 2σ(I) for complex 2; and a = 9.308(3), b = 15.357(3), c = 17.419(4) A, α = 66.493(13), β = 88.61(2), γ = 86.664(19)°, V = 2279.4(9) A3, Z = 2, Dc = 1.499 g/cm3, F(000) = 1046, μ(MoKα) = 1.364 mm-1, R = 0.0843 and wR = 0.2280 for 8433 observed reflections with I 2σ(I) for complex 3. Each central metal in complexes 1 and 2 is six-coordinated by three nitrogen and three oxygen atoms from three β-ketoiminate ligands to give a distorted octahedral geometry, while the central metal in 3 is seven-coordinated by three nitrogen and three oxygen atoms from three β-ketoiminate ligands and one oxygen atom from the solvated THF molecule to complete a distorted monocapped trigonal prism.     

利用珍珠岩尾粉制备发泡材料

以信阳珍珠岩尾粉、凝灰岩为主要原料,石墨为发泡剂,添加适量废玻璃粉、添加剂,在不同的温度下烧制成发泡材料.利用热分析仪分析了混合料的发泡温度,用x射线衍射仪、压力试验机等对样品进行结构表征和性能测试.结果表明:珍珠岩尾粉凝灰岩发泡材料合适的发泡温度为930?.保温时间为30min,样品密度为0.43g/cm3,抗压强度...     

表面抗菌功能涂层的构建及在生物医用材料中的应用研究

近年来,生物医用材料在使用过程中产生的医源性感染问题层出不穷,对人们健康和生命造成严重威胁.表面抗菌涂层构建是解决该类医源性感染问题最有效的策略之一.目前,按照作用机制和功能不同将表面抗菌涂层分为接触式抗菌涂层、抗黏附抑菌涂层、抗黏附杀菌涂层以及智能抗菌涂层.表面抗菌涂层的构建不仅赋予了生物医用材料抗菌性能,有效解决了上述医源性感染问题,还可以提高材料的生物相容性,赋予其抗黏附、抗氧化、生物识别、传感等功能.本文旨在对目前表面抗菌涂层的种类、构建方法以及其在生物医用材料领域中的应用做一全面论述,为进一步开发高性能表面抗菌涂层并扩展其应用提供新思路.     

厚薄板通用三角形广义协调元TCGC-T9的固有振动分析

研究了厚薄板通用三角形广义协调单元TCGC-T9的固有振动特性.通过编制程序,采用子空间迭代法求得不同板厚的前5阶固有频率值,并将计算结果与理论解和有限元软件ABAQUS的结果进行比较.结果表明:TCGC-T9单元在固有振动分析方面收敛速度快,数值稳定性好、实用性强(无需区分厚板和薄板).     

收敛序列上的连续函数下方图形超空间

Let S={1,1/2,1/2 2,…,1/∞=0} and I = [0,1] be the unit interval. We use ↓USC(S) and ↓C(5) to denote the families of the regions below of all upper semi-continuous maps and of the regions below of all continuous maps from S to I and ↓C0(S) ={↓f∈↓C(S):f(0)=0}.↓USC(S) endowed with the Vietoris topology is a topological space. A pair of topological spaces (X, Y) means that X is a topological space and Y is its subspace. Two pairs of topological spaces (X, Y) and (A, B) are called pair-homeomorphic (≈) if there exists a homeomorphism h:X→A from X onto A such that h{Y) = B. It is proved that, (↓USC(S), ↓C0(S))≈(Q,s) and (↓USC(5), ↓C(5)\↓C0(S))≈(Q,c0), where Q =[-1, l]ω is the Hilbert cube and s=(-1,1)ω, c0 = {(xn)∈Q:lim n→∞ xn=0}. But we do not know what (↓USC(S),↓C(5)) is.