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991.
目的 了解温州地区维持性血液透析患者矿物质代谢紊乱情况及相关影响因素。方法 收集2013 年在温州地区长期维持性血液透析患者血钙、血磷、全段甲状旁腺激素(iPTH)的资料,并根据美国肾脏病协会指南(KDOQI)及中华医学会肾脏病学分会(CSN)制订的《慢性肾脏病矿物质和骨异常诊治指导》计算患者的血钙、血磷、iPTH 的达标率,并对相关影响因素进行分析。结果 共收集2 227 例2013 年在温州地区各家透析中心维持性血液透析患者的资料。按KDOQI 指南标准,患者血钙、血磷、iPTH 的达标率分别为44.90%、46.30%、27.64%,3 项均达标者占6.29%;按《慢性肾脏病矿物质和骨异常诊治指导》建议,患者血钙、血磷、iPTH 的达标率分别为57.66%、46.30%、61.14%,3 项均达标者占16.97%。此外,三级医院维持性血液透析患者的平均血磷水平为(1.67±0.51)mmol/L,血磷达标率49.10%,二级医院患者的平均血磷水平为(1.79±0.53)mmol/L,达标率为43.22%,三级医院维持性血液透析患者的血磷达标率情况优于二级医院。血白蛋白、含钙磷结合剂的使用及透析频率是影响血钙达标的独立相关因素。患者的性别、年龄、活性维生素D 的使用、透析龄及透析频率是影响血磷达标的独立相关因素。患者活性维生素D的使用是影响iPTH 达标的独立相关因素。结论 温州地区维持性血液透析患者矿物质代谢紊乱纠正情况与有关指南的要求仍然存在较大差距;患者性别、营养状态、透析频率、含钙磷结合剂的服用、活性维生素D 的使用等是影响维持性血液透析患者矿物质代谢紊乱纠正的主要相关因素。 相似文献
992.
On semipolar epitaxial ZnO grown by chemical vapor deposition consists of two distinct orientations as evidenced by transmission electron microscopy and X‐ray diffraction. The initially grown ZnO on GaN follows the GaN lattice with the epitaxial relationship of // and The other oriented ZnO domains then grow on faceted with and with good coherency with the ‐oriented grains. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
993.
Jianyu Wang Huabin Sun Yun Sheng Fan Gao Yao Yin Yun Li Lijia Pan Youdou Zheng Yi Shi Takashi Sekiguchi 《固体物理学:研究快报》2015,9(8):466-469
Surface‐diffusion‐induced spontaneous Ga incorporation process is demonstrated in ZnO nanowires grown on GaN substrate. Crucially, contrasting distributions of Ga atoms in axial and radial directions are experimentally observed. Ga atoms uniformly distribute along the ~10 μm long ZnO nanowire and show a rapidly gradient distribution in the radial direction, which is attributed substantially to the difference between surface and volume diffusion. The understanding on the incorporation process can potentially modulate doping and properties in semiconductor nanomaterials.
994.
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996.
Ordered Mesoporous Carbon and Thiolated Polyaniline Modified Electrode for Simultaneous Determination of Cadmium(II) and Lead(II) by Anodic Stripping Voltammetry 下载免费PDF全文
Lin Tang Jun Chen Guangming Zeng Yuan Zhu Yi Zhang Yaoyu Zhou Xia Xie Guide Yang Sheng Zhang 《Electroanalysis》2014,26(10):2283-2291
The fabrication and evaluation of a glassy carbon electrode (GCE) modified with ordered mesoporous carbon (OMC), 2‐mercaptoethanesulfonate (MES)‐tethered polyaniline (PANI) and bismuth for simultaneous determination of trace Cd2+ and Pb2+ by differential pulse anodic stripping voltammetry (DPASV) are presented here. The morphology and electrochemical properties of the fabricated electrode were respectively characterized by scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). Experimental parameters such as PANI disposition, preconcentration potential, preconcentration time and bismuth concentration were optimized. Under optimum conditions, the fabricated electrode exhibited linear calibration curves ranged from 1 to 120 nM for Cd2+ and Pb2+. The limits of detection (LOD) were 0.26 nM for Cd2+ and 0.16 nM for Pb2+ (S/N=3), respectively. Additionally, repeatability, reproducibility, interference and application were also investigated, and the proposed electrode exhibited excellent performance. The proposed method could be extended for the development of other new sensors for heavy metal determination. 相似文献
997.
Ming-Wei Hong Li Song Yi Zhao Lai-Shun Qin Cong-Yong Wang Hong-Sheng Shi Jia-Yu Guo Xiao-Dong Tao Kang-Ying Shu Wen-Xiang Chai 《Journal of Cluster Science》2014,25(6):1627-1640
A series of strongly phosphorescent copper(I) halide complexes, namely [Cu(μ-X)POP]2 (X = Cl (1), Br (2), I (3), Br0.5Cl0.5 (4), POP = bis[2-(diphenylphosphino)phenyl]ether), have been synthesized by reacting CuX with the diphosphine ligand in 1:1 molar ratio. All complexes were characterized by spectroscopic analysis (IR, UV–Vis), elemental analysis, and photoluminescence study. Single-crystal X-ray diffraction revealed that complex 2 is a dinuclear structure which is constructed by two μ-X bridges and two POP ligands as μ2 bridges. Other complexes were determined as isologues of complex 2 by powder X-ray diffraction and elemental analysis. All complexes exhibit intense blue-green phosphorescence with a lifetime of ~1 μs in the solid state. The halogen-mixed complex presents a lightly change in the luminescence comparing to that of parent complexes. The excited states of all complexes have been assigned as halide-to-ligand charge transfer state mixed metal-to-ligand charge transfer character based on the time-dependent density functional theory calculations. All complexes are thermally stable according to thermogravimetric analysis so that they are suitable for applying in luminescent devices. 相似文献
998.
Ting Wu Yi Ping Du Dong Jiang Bo Hao Yu 《International Journal of Polymer Analysis and Characterization》2014,19(5):441-452
The aim of this work is to discriminate thermoplastic polyester-polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polytrimethylene terephthalate (PTT), which cannot be easily identified by many methods. Both matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) and pyrolysis gas chromatography/mass spectrometry (Py-GC/MS) were applied to identify these polyesters owing to their analytical ability to determining polymers' chemical structure. The three thermoplastic polyesters can be easily distinguished by MALDI-TOF MS according to their different repeated units. Py-GC/MS was used to analyze their specific pyrolyzates. The three polyesters can be identified through their characteristic pyrolysis products as well. 相似文献
999.
Qinglin Dong Yijie Bian Yi Li Changyu Han Lisong Dong 《Journal of Thermal Analysis and Calorimetry》2014,118(1):359-367
Stereocomplex-poly(l- and d-lactide) (sc-PLA) and poly(methyl methacrylate) (PMMA) blends were prepared by solution blending at PMMA loadings from 20 to 80 mass%. The miscibility and crystallization behaviors of the blends have been studied in detail by differential scanning calorimeter. The single-glass transition temperatures (T g) of the blends demonstrated that the obtained system was miscible in the amorphous state. It was observed that the crystallization peak temperature of sc-PLA/PMMA blends was marginally lower than that of neat sc-PLA at various cooling rates, indicating the dilution effect of PMMA on the sc-PLA component to restrain the overall crystallization process. In the study of isothermal crystallization kinetics, the reciprocal value of crystallization peak time ( \( t_{\text{p}}^{ - 1} \) ) decreased with increasing PMMA content, indicating that the addition of non-crystalline PMMA inhibited the isothermal crystallization of sc-PLA at an identical crystallization temperature (T c). Moreover, the negative value of Flory–Huggins interaction parameter (χ 12 = ?0.16) of the blend further indicated that sc-PLA and PMMA formed miscible blends. 相似文献
1000.
Guishan Zou Xiukang Yang Xianyou Wang Long Ge Hongbo Shu Yansong Bai Chun Wu Haipeng Guo Liang Hu Xin Yi Bowei Ju Hai Hu Di Wang Ruizhi Yu 《Journal of Solid State Electrochemistry》2014,18(7):1789-1797
The Li-rich Li1.3[Ni0.35Mn0.65]O2+x microspheres are firstly prepared and subsequently transferred into the Al2O3-coated Li-rich Li1.3[Ni0.35Mn0.65]O2+x microspheres by a simple deposition method. The as-prepared samples are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and charge/discharge tests. The results reveal that the Al2O3-coated Li-rich Li1.3[Ni0.35Mn0.65]O2+x sample has a typical α-NaFeO2 layered structure with the existence of Li2MnO3-type integrated component, and the Al2O3 layer is uniformly coated on the surface of the spherical Li-rich Li1.3[Ni0.35Mn0.65]O2+x particles with a thickness of about 4 nm. Importantly, the Al2O3-coated Li-rich sample exhibits obviously improved electrochemical performance compared with the pristine one, especially the 2 wt.% Al2O3-coated sample shows the best electrochemical properties, which delivers an initial discharge capacity of 228 mAh g?1 at a rate of 0.1 C in the voltage of 2.0–4.6 V, and the first coulombic efficiency is up to 90 %. Furthermore, the 2 wt.% Al2O3-coated sample represents excellent cycling stability with capacity retention of 90.9 % at 0.33 C after 100 cycles, much higher than that of the pristine one (62.2 %). Particularly, herein, the typical inferior rate capability of Li-rich layered cathode is apparently improved, and the 2 wt.% Al2O3-coated sample also shows a high rate capability, which can deliver a capacity of 101 mAh g?1 even at 10 C. Besides, the thin Al2O3 layer can reduce the charge transfer resistance and stabilize the surface structure of active material during cycling, which is responsible for the improvement of electrochemical performance of the Li-rich Li1.3[Ni0.35Mn0.65]O2+x . 相似文献