无关供者骨髓移植治疗多次复发性急性白血病

文章探讨无关供者骨髓移植治疗多次复发急性白血病的疗效 .经改良 Bucy方案预处理后对一例第三次复发的急粒患者行无关供者骨髓移植 ,同时给防治 GVHD、抗感染治疗 .结果 + 2 1天骨髓在患者体内植活 ,+ 35天细胞染色体分析呈供者型 ( 4 6,XX.正常核型 ) ,+ 84天血型转换成供者型 ,至今已无病生存超过 6个月 .结果表明 ,无关供者骨髓移植对多次复发的急性白血病患者具有治疗价值     

毛发水解制取胱氨酸过程中杂质的来源及除去方法

本文阐述了以毛发为主要原料生产Ｌ－胱氨酸过程中杂质的来源，种类及除去方法，并提供了有关的反应条件。     

GaN/AlxGa1-xN量子点中的激子态

在有效质量近似框架内,运用变分方法,考虑内建电场效应和量子点的三维约束效应,研究了含类氢杂质的G aN/A lxG a1-xN量子点中的激子态.结果表明:量子点中心的类氢杂质使激子的基态能降低,结合能升高,Q D系统的稳定性增强,光跃迁能减小;杂质位于量子点上界面时,激子的基态能最小,结合能最大,系统最稳定;随着杂质从量子点的上界面沿着z轴移至下界面,激子基态能和光跃迁能增大,结合能减小.     

Numerical and analytic study of rough surface morphology on the angular distribution of eroded impurity

The impact of rough surface morphology on the angular distribution of eroded impurities has been investigated with the three‐dimensional (3D ) rough surface code SURO and a newly developed analytic model. The property of the rough surface structure can be described by the shadow angle of the rough surface in SURO , which is defined as the ratio of the horizontal characteristic length to the initial surface roughness. The SURO simulation results show that the influence of the rough surface on the angular distribution of eroded impurities comes into play when the shadow angle is larger than a threshold value. The larger shadow angle of the rough surface leads to a stronger shift of the angular distribution of the eroded impurities. Different rough surface topographies have been used in the SURO code to check the angular distribution of the eroded impurities. It is found that the shift tendency of the angular distribution is similar for different structures of the rough surface. Based on the numerical modelling results, an analytical model has been developed to investigate the impact of the shadow angle on the angular distribution of the eroded impurities, which shows the consistent result as the SURO simulations.     

Synthesis and photovoltaic properties of main chain polymeric metal complexes containing 1,10‐phenanthroline metal complexes conjugating alkyl fluorene or alkoxy benzene by C═C bridge for dye‐sensitized solar cells

Four main chain polymeric metal complexes (P1–P4) based on 1,10‐phenanthroline metal complexes via the Heck coupling have been synthesized and characterized by Fourier transform infrared spectroscopy, ¹H NMR, UV–Vis absorption, photoluminescence spectroscopy, gel permeation chromatography, thermogravimetric analysis, differential scanning calorimetry, elemental analysis, and cyclic voltammetry. To investigate their photovoltaic properties, the dye‐sensitized solar cells based on these polymers dyes are studied, under the illumination of AM 1.5G, 100 mW/cm². The study results show the four polymers exhibit good thermally stable and the solar cells based on them have good device performance, and the maximum power conversion efficiency is up to 0.735% for the solar cells based on P3 with a short‐circuit current (J_sc) of 1.68 mA/cm² and an open‐circuit voltage (V_oc) of 0.62 V. Copyright © 2012 John Wiley & Sons, Ltd.     

Thermoluminescence of Chromium Doped Cd2Nb2O7 Crystals

The exposure of the Cd₂Nb₂O₇:Cr crystal to monochromatic light with wavelength shorter than 600 nm at 12 K decreases the Cr^3? photoluminescence emission and allows us to observe thermoluminescence within 60–200 K during subsequent heating of the crystal at a rate of 0.077 K/s. The glow curve of thermoluminescence revealed a rather complex structure with two pronounced intensive glow peaks at 91 and 180 K and four rather weak peaks at 99, 117, 132, and 155K. An analysis of the glow peaks by “an initial rise” gave evidence of many various charge carrier traps with activation energies from 150 to 470 meV. Since a comparison of the thermoluminescence and photoluminescence emission spectra showed that these spectra are identical, it was concluded that the thermoluminescence glow peaks are associated with thermal release of charge carriers from shallow traps followed by Cr^4?→Cr^3?(²E) and/or Cr^2?→Cr^3?(²E) charge capture and ²E→⁴A₂ radiative decay of Cr^3?(²E) ions.     

Chiral 2-(2-hydroxyaryl)alcohols (HAROLs) with a 1,4-diol scaffold as a new family of ligands and organocatalysts

Efficient and modular syntheses of chiral 2-(2-hydroxyaryl)alcohols (HAROLs), novel 1,4-diols carrying one phenolic and one alcohol hydroxyl group, have been developed which led to generation of a small library of structurally diverse HAROLs in enantiomerically pure form. Of the different HAROLs examined, a HAROL based on the indan backbone exhibited the highest activity and enantioselectivity in the 1,2-addition of certain organometallic compounds to aldehydes in the presence of Ti(OⁱPr)₄ (up to 97% y, 88% ee) and performed as a hydrogen-bond donor organocatalyst in the Morita-Baylis-Hillman reaction, promoted by trialkylphosphines.     

N → Sn coordination in the complexes of tin halides with pyridine: A comparison between Sn(II) and Sn(IV)

The experimentally well‐known complexation of tin(II) and tin(IV) halides with pyridine (py) leads to structures showing N → Sn coordination. In the present work, the complexes SnX_n·mpy (where X = F, Cl, Br, I; n = 2, 4; m = 1, 2) possessing this kind of coordination were studied using a computational quantum chemical approach. Various aspects in the theoretical picture of these complexes were examined to find similarities and differences in their N → Sn coordination. The aspects included, among others, the physical nature of intermolecular interactions, and their role in establishing the structure and energetic stabilization of the complexes. In this context, the effect of tin valency was inspected in great detail. As proven by several theoretical methods, a largely ionic character with a certain covalent component can be attributed to the studied N → Sn coordination, irrespective of tin valency. All complexes are destabilized by py‐py and three‐body interactions, but the Sn(II) complexes experience it to a greater extent. Marked differences are observed in the structural behavior of N → Sn and SnX_n during complex formation. This affects the energetics of complexation and, in consequence, the penta‐coordinated Sn(IV) center shows a higher propensity to expand its coordination number, compared with the tri‐coordinated Sn(II) center. The present study supplements the experimental characterization of SnX_n·mpy and, in general, it sheds light on the coordination of heteroaromatic nitrogen to tin. The survey of the Cambridge Structural Database revealed that such coordination occurred in a number of crystal structures.     

PROTONATION CONSTANTS AND SOLVENT DEPENDENT SPIN-CROSSOVER BEHAVIOUR OF IRON(II)-2-(2′-PYRIDYL)BENZIMIDAZOLE COMPLEXES

Abstract

2-(2′-Pyridyl)benzimidazole (pybzim = LH) coordinates to iron(II) as a bidentate and forms the tris-ligated complex, [Fe(pybzim)₃]²⁺ as isolated in the solid. Titration of [Fe(pybzim)₃]²⁺ with base demonstrates the successive deprotonation of the imino hydrogens of the coordinated ligands. Protonation constants for the free ligand, pybzim (Iog₁₀ K ^H = 11.33) and the complex, [Fe(pybzim)₃]²⁺ (log₁₀ K ^H ₁ = 9.58, log₁₀ K ^H ₂ = 8.13 and log₁₀ K ^H ₃ = 6.97) were measured in 30% (v/v) H₂O/EtOH. Results show that coordination to iron(II) increases the acidity of the imino hydrogen of the ligand. Spin-crossover behaviour of the complex were studied in different solvents ME, AC, AN, NM, NB, DMF, DMSO and ANL. The complex shows strong spin-crossover behaviour which is solvent dependent. Values of the spin-equilibrium constant (K _sc) and the associated thermodynamic parameters (ΔH _sc = 18.1–21.3 kJ mol^?1 and δS _sc = 69.6–84.4JK^?1 mol^?1) were calculated. An increase of the enthalpy is observed with increasing donor number (DN) of the solvent.