点阵素单位与复单位中晶面指标的标定

本文就点阵素单位与复单位中晶面指标的标定问题，从点阵周期性的角度出发，作了一些讨论     

X射线Fourier多峰解析法测定晶粒大小分布及微观应力的研究

1 实验部分 1.1 原理设X射线衍射峰的纯加宽(包括晶粒度和微观应力引起的加宽)峰形为f(y),仪器峰形为g(z),样品峰形为h(x),有: A_n=F_R(n)=[H_R(n)·G_R(n)+H_I(n)·G_I(n)]/(G_R~2+G_I~2) B_n=F_I(n)=[H_I(n)·G_R(n)-H_R(n)·G_I(n)]/(G_R~2+G_I~2) 式中N为衍射峰形的最大底宽,n为谐波指数,j=±1,±2,…±N/2,H_R,H_I,G_R和G_I分别为样品峰形函数和仪器峰形函数的Fourier系数,A_n,B_n是纯加宽峰形的Fourier系数。     

常见先心病X线平片分析及其诊断价值探讨

了解常见先心病X线平片上畸形的诊断特点。方法对攀枝花市中心医院十几年来收治的258例先心病(男性150例，女性108例)包括房缺、室缺、动脉导管未闭及法乐氏四联征的平片分析，并结合手术、超声心动图、心导管等检查结果进行分析比较。结果尽管超声心动图、心血管造影等检查在先心病诊断中应用愈来愈广泛，但胸片在先心病诊断中仍有相当价值，不失为先心病最基本检查手段，尤其是单发畸形。结论X平片对先心病有重要诊断价值，但要注意尽量避免或减少影响诊断率的因素。     

岩石高温轴向应力测试装置的研制

介绍了自行设计研制的岩石高温轴向应力测试装置的结构、设计过程。该应力测试装置是为研究煤炭地下气化炉围岩在高温下应力应变关系而设计的，它能测试20～1200％下的岩石的热膨胀应力。     

The DNA concentration effect on DNA radiation damage induced by <Superscript>7</Superscript>Li ions and γ rays

To evaluate the influence of the DNA concentration in the aqueous solution on DNA radiation damage, the plasmid DNA in the presence or absence of Mannitol （scavenger of free radical OH.） was irradiated by ^7Li ions and γ rays at various DNA concentrations. Gel electrophoresis analysis revealed that the DNA damage of single and double strand breaks induced by irradiation became more severe at lower DNA concentration. In the condition of γ-ray irradiation, most of double strand breaks （DSB） damage was neutralized and less associated with DNA concentration in the presence of mannitol. However, under ^7Li irradiation, DSB damage could not be cleared by mannitol but was gradually aggravated with decreasing DNA concentrations. These findings imply that under low-LET irradiation, most of the DSB damage is generated by free radical OH·diffusion, and thus may be counteracted by scavengers, while at higher-LET irradiation, quite a fraction of DSB induction is caused by direct ionizing energy deposition of heavy ions, which cannot be eliminated. This work also indicates that the proportion between free radical damage and direct ionizing damage is s constant which is independent of DNA concentration when the DNA concentration is under a certain value （50ng/μL）. Our study sheds light on the un- derlying mechanisms in the DNA radiation damage process.     

离焦情况下波带片衍射光强的数值计算

基于非傍轴近似下菲涅耳 -基尔霍夫积分公式 ,讨论了波带片在离焦条件下的光斑特性 .通过数值计算 ,分别得到了在小离焦量和大离焦量时光强沿光轴径向的分布曲线、中心光斑的大小以及在特定范围内总能量随离焦量的变化规律 .为实际工作中应用波带片提供了更好的理论依据 .     

混合溶剂热法合成Cu7S4对称的六角棱台

以CuCl2·2H2O为铜源,H2NCSNHNH2为硫源,通过水和乙二胺中制备出Cu7S4对称六角棱台.通过X射线粉末衍射(XRD)、透射电子显微镜(TEM)和场发射扫描电子显微镜(FESEM)对所得产品进行了结构表征.XRD结果证实产物为正交相,其晶格常数为a=0.791 4 nm,b=0.784 4 nm,c=1.108 3 nm.SEM结果显示样品的形貌为对称六角棱台:这些六角棱台的最大平面直径约为420 nm,厚度为180 nm.样品的光学性质通过紫外光谱和稳态荧光谱(PL)进行了表征,并讨论了样品的可能生长机制.