深圳市养老保障资源配置问题探究

以国家"先行示范区"深圳市为例,首先,将深圳市与具有国际先进养老水平的美国和日本进行对比,确定养老院床位数作为需要量化描述的指标;其次,分别采用长短时记忆神经网络模型和平移预测模型预 测常住人口数和老年人口数,并且参照美国养老水平求解量化指标;最后,以行政区域为单位,将各区需增养老院床位数和闲置土地面积的基尼系数为 目...     

芦丁热稳定性的红外光谱法实时原位跟踪

本文首次利用傅叶变换红外光谱法和变温附件」产时原位跟踪了天然药物芦丁折为性过程。结果表明：２５℃－２７０℃温度范围内,芦丁的热变性过程是一个伴随着芦丁氧化的热分解过程。在较低温度下（７５℃）芦丁的分子结构就开始发生变化,不仅暗示了中国态的存在,还进一步验证芦丁的稳定性较差;在较高温度下（２７０℃）芦丁分解成两种产物。该方法快速、准确、无溶剂效应,可进行榈的无损原位检测。     

Two-Photon Micromaser with Initial Atomic Coherence

We investigate the quantum dynamics of a two-photon micromaser pumped by atoms injected in the superposition state of the upper and intermediate levels. We simulate a master equation governing the system by the Monte Carlo wavefunction approach and analyse the steady-state behaviour as a function of the atomic transit time. The atomic coherence can effectively enhance the intensity and sub-Poissonian of the cavity field as compared with the atomic mixture. It is also discovered that the phase of the cavity field can be shifted by adjusting the detuning between the atom and field. This result shows that it is possible to manipulate the phase of the cavity field by detuning, due to atomic coherence.     

小型硅胶柱分离氢化物原子吸收测定铅及铅锑合金中微量锡

已有的测定铅及其合金中微量锡的分光光度法和火焰原子吸收法对测定锡含量低于0.001％时有一定困难。近年发展的电热氢化锡原子吸收法灵敏度达0.nppb,无论采用何种方法测定,大量基体均存在着不同程度的干扰。本文提出在测定溶液中加入酒石酸钠以降低酸度的影响。采用小型硅胶柱分离干扰元素,用小体积低浓度HCl为洗脱液,改善了测定下限。样品处理方法简便,取样量少(0.1～0.3克),适合于含量在0.01～0.00004％锡的测定。测定结果与发射光谱相符。     

模糊聚类-因子分析法解析稀土配合物吸收峰的研究

将模糊聚类分析与因子分析相结合,对地质样品中吸收光谱严重重叠的稀土多组份体系进行解析,较好地解决了计算光度分析中校准模型的优化问题。对数据库的建立、聚类参数选择等问题进行了讨论。对地质样品中15个稀土元素进行了同时测定,标准偏差小于1.2。     

乙二胺溶剂热法合成YAG∶Ce超细粉体及发光性能研究

本文采用溶剂热法合成YAG∶ Ce超细粉体,利用热分析(TG/DSC)/X射线衍射(XRD)/红外光谱((FTIR)/扫描电镜(SEM) /光谱等分析方法系统的分析了热溶剂法合成时间、填充度、Ce3+掺杂浓度等对粉体性能的影响.结果分析表明:以NH4HCO3为沉淀剂的前驱体均匀分散在乙二胺溶剂中,在220℃下溶剂的填充度为75;并保温48 h可以得到纯的YAG相,组成为Y2.94Ce0.06A5G12超细粉体发光效果最佳.粉体粒径分布窄,分散性好,粒径主要集中在200 nm左右.     

压强效应下Ba2YNbO6的弹性性质与电子结构的第一性原理计算

采用基于密度泛函理论的平面波赝势方法,计算了不同压强下立方结构双钙钛矿氧化物Ba2YNbO6的弹性性质与电子结构.计算结果表明:平衡状态下Ba2YNbO6为延展性材料,且延展性随压强的增大而提高;弹性常数,弹性模量和泊松比均随压强的增大近线性增大;Ba2YNbO6为直接带隙半导体,平衡状态下带隙宽度为2.55 eV,且带隙值随压强的增大而减小;费米面附近的能带主要由O 2p,Nb 4d和Y 4d层的电子态密度确定,增大压强使态密度峰有偏离费米面的趋势,并且态密度展宽,峰发生劈裂.     

导弹动爆对模拟船舱毁伤效果试验研究

 设计了基于火箭橇的导弹动爆试验,介绍了模拟船舱的结构尺寸、测试点的布设情况及测试仪器性能。通过获取的断线、光、压力、加速度信号得出如下结论：测试方法有效;冲击波在舱室内传播不均匀,导弹运动方向反射冲击波很大,反方向较小,两者比例可达3.5∶1,舱室的角隅部位冲击波压力高于壁面正反射压力;导弹穿甲时舱壁的冲击振动高达10 000 g,且穿甲舱壁的冲击远大于其它舱壁,被破片击中会加大舱壁的振动幅值。     

吸附在活性炭上的二氧六环类固相和类液相性质的NMR研究

In this paper a study of the spin lattice relaxation times of dioxane(DO) adsorbed on various charcoals is presented. Results show that the magnetziation of DO decays biexponentially (Table 1) as observed in the case of adsorbed hydrocarbons~[6]. The fast relaxing molecules are considered to be those adsorbed in micropores with radii less than 1.0 nm whose motion is restricted and slowed down, thus they form a solid like phase. However, the slow relaxing ones are those condensed in the micropores, they are free to move and form the liquid like phase. Molecules condensed in the interior of the micropores exchange rapidly with those situated in the vicinity of the pore wall according to Eq.(2).Comparison of data in Table 1 may lead to a conclusion that charcoal with greater density of surface acidic groups and greater percentage of pore capacity with radius<1.0 nm (V_(10)/V_(30)) has a greater percentage of solid like phase (P_f). Although V_(10)/V_(30) of density of surface acidic groups. It is apparent that surface acidic groups in micropores play an important role in the formation of solid like phase of DO on charcoals. It seems that DO form hydrogen bond with the surface acidic groups. It is this hydrogen bond and the hinderance effect of pores restrict the DO from moving freely, which results in the formation of the so called solid like phase. It can be found from small (0.10 ml/gC). This implies that DO vapour may first condense in the micropores having more acidic groups and higher activation energy, and then fill in other pores step by step as the adsorption process proceeds.     

利用微波辅助[3+3]环化反应合成稠合吡啶衍生物

报道了一类新型的微波辅助对甲基苯磺酸促进的[3+3]环化反应.利用烯胺酮或烯胺内酯可作为1,3-双亲核试剂及炔丙醇可作为1,3-双亲电试剂的特性,使其在微波辐射及对甲苯磺酸促进条件下于冰醋酸中在70℃反应,实现了[3+3]环化反应,分别区域选择性地合成了 2,2-二芳基取代四氢喹啉-5(1H)-酮衍生物和2,2-二芳基...