单扫描示波极谱测定痕量银

本文首次提出了运用单扫描极谱直接测定银的方法。在含N-烯丙基-N′-对苯磺酸钠硫脲及四乙烯五胺的硼砂缓冲液中,银离子在-0.66V(相对饱和甘汞电极)有一灵敏还原波。运用经典极谱或单扫描极谱,此波均可用于微量银的定量测定。“银波”的单扫描示波极谱波可在5×10~(-7)～3×10~(-5)mol/L范围内检测银。方法已用于废定影液中银含量的分析,结果满意。     

热辐射驱动烧蚀平面金靶的数值定标定律

利用一维辐射流体力学编码数值研究了辐射烧蚀波在平面金靶中的传播情况,并在常温边界条件下得到了辐射流、烧蚀压、质量烧蚀率和特征等离子体密度的定标定律。     

PARAMETER ESTIMATION OF SPATIAL AR MODEL

Consider a stable AR model of two parameter spatial series {X_t, t∈N~2}, i. e. {X_(t)t∈N~2} is homogeneous and satisfies the following difference equationX_t-sum from n=s∈相似文献   

Growth and optical properties of a new self-Q-switched laser crystal: Cr:Yb3Al5O12

Cr⁴⁺:YbAG (Cr⁴⁺:Yb₃Al₅O₁₂) crystal with a size up to Φ24 mm×30 mm was grown by the Czochralski method. In the absorption spectrum, there are two absorption bands at 939 and 969 nm, respectively, which are suitable for InGaAs diode laser pumping, and there is an absorption band at 1030 nm, which is suitable for passive Q-switched laser output at 1.03 μm. A broad emission spectrum from 970 to 1100 nm was exhibited from 940 nm wavelength pumping. This crystal is promising as a self-Q-switched laser crystal used for compact, efficient, highly stable, passive self-Q-switched thin chip solid-state lasers.     

Research on Hawking Radiation as Tunneling from Schwarzshild-anti-de Sitter Black Hole

After taking into account energy conservation and the particle’s self-gravitation interaction, Hawking radiation of the massive particle as tunneling from Schwarzshild-anti-de Sitter black hole is studied by using Parikh-Wilczek’s semi-classical quantum tunneling approach. Meanwhile, Hawking radiation as tunneling from the black hole is reexamined by developing Angheben–Nadalini–Vanzo–Zerbini (ANVZ) covariant method to cover energy conservation and the particle’s self-gravitation interaction. Both the results perfectly generalize those obtained by Parikh and Wilczek, and show that the tunneling rate is related to the change of Bekenstein-Hawking entropy, and the factual emission spectrum is not exactly thermal, but satisfies the underlying unitary theory. PACS: 04.70-s, 9760. Lf.     

Propagation of thickness-twist waves in a multi-sectioned piezoelectric plate of 6 mm crystals

We study thickness-twist vibrations and waves in an unbounded, multi-sectioned piezoelectric plate of crystals with 6 mm symmetry or polarized ceramics. An exact solution from the three-dimensional equations of piezoelectricity is obtained. Basic vibration and wave propagation characteristics are calculated based on the solution. The results are useful in the understanding and design of plate resonators, filters and acoustic wave sensors of ZnO, AlN and polarized ceramics.     

Explicit bounds on some new nonlinear integral inequalities with delay

The purpose of the present note is to establish some new delay integral inequalities, which provide explicit bounds on unknown functions and generalize some results of Li et al. [Some new delay integral inequalities and their applications, J. Comput. Appl. Math. 180 (2005) 191–200]. The inequalities given here can be used to investigate the qualitative properties of certain delay differential equations and delay integral equations.     

Periodic and subharmonic solutions of a class of subquadratic second-order Hamiltonian systems

Some solvability conditions of periodic and subharmonic solutions are obtained for a class of subquadratic nonautonomous second-order Hamiltonian systems by the minimax methods in critical point theory.     

2,2’—二硫代双(4,6—二叔丁基苯酚)的晶体和分子结构

一种塑解剂经高压液体色谱分离制备出主要成份2,2′—二硫代双(4,6二叔丁基苯酚)。由质谱分析得到分子量为474化学式为C_(28)H_(2)O_2S_2、晶体呈现孪生。基体单晶属三斜晶系,空间群为(?)PI(NO.2),晶体结构用直接法解出,=0.07。研究结果表明该分子是二硫代酚类化合物。在EI场中,S—S键断裂是主要断裂过程。晶体中,分子的一个环上的羟基是无序分布的。羟基与最邻近的硫原子形成氢键。     

新型高色纯度弱电流猝灭性蓝色有机发光器件

以ADN为基质,分别以不同掺杂剂制备了四种蓝色有机发光器件,器件结构为:CuPc(12 nm)/NPB(40 nm)/AND∶Dopant(50 nm)/Alq(12 nm)/LiF(4 nm)/Al。掺杂剂有:BCzVB(amino-substituted distyrylarylenederivatives)、TBPe、BCzVBi和DSA-ph四种。研究了最佳掺杂浓度以及器件的亮度、电流密度、效率和色坐标等电学特性和光学特性。其中掺杂BCzVB制备了色纯度高、低电流猝灭性的蓝色有机发光器件,色坐标达到x=0.146,y=0.162,最大亮度为11600 cd/m2(15 V),电流效率为2.8 cd/A,流明效率为1.79 lm/W;以ADN为基质,分别以TBPe、BCzVBi和DSA-ph为掺杂剂,制备了另外三种对比器件。器件ADN∶TBPe色坐标为x=0.162,y=0.222(蓝绿光),效率随电流的增加而降低很快;器件ADN∶BczVBi有较好的色纯度(色坐标:x=0.164,y=0.146),但电流效率较低:2.03 cd/A,效率随电流的增加降低幅度也较快。器件ADN∶DSA-ph效率较高为8 cd/A,效率随电流增加变化幅度不大,但色纯度比较差(x=0.153,y=0.306),适合于做白色有机发光器件。