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991.
研究得出 (Na+ ,K+ ,Mg2 +∥ Cl-,SO2 -4 -H2 O)五元体系 3 5℃时的介稳溶解度数据 ,绘制了该体系 3 5℃的介稳相图 ,共有 9个为氯化钠所饱和的结晶区域 :氯化钾、钾芒硝 (3 K2 SO4 · Na2 SO4 )、钾镁矾 (K2 SO4· Mg SO4 · 4 H2 O)、钾盐镁矾 (KCl· Mg SO4 · 2 .75H2 O)、光卤石 (KCl· Mg Cl2 · 6H2 O)、白钠镁矾 (Na2 SO4· Mg SO4 · 4 H2 O)、硫酸钠、六水硫酸镁 (Mg SO4 · 6H2 O)和水氯镁石 (Mg Cl2 · 6H2 O) .所得 3 5℃介稳相图与 Van t Hoff2 5℃稳定相图比较有较大区别 :软钾镁矾 (K2 SO4 · Mg SO4 · 6H2 O)、七水硫酸镁、五水硫酸镁及四水硫酸镁结晶区域消失 ,钾镁矾和钾盐镁矾结晶区域显著扩大 .所得 3 5℃介稳相图与 2 5℃介稳相图区别很大 :软钾镁矾和七水硫酸镁结晶区域消失 ,同时出现了钾镁矾和钾盐镁矾的结晶区域 .在该五元体系 3 5℃介稳相平衡研究中发现析出的是钾盐镁矾的低水化合物 (KCl·Mg SO4 · 2 .75H2 O) 相似文献
992.
二元表面活性剂溶液表面吸附层分子交换能的研究 总被引:3,自引:0,他引:3
由于分子间存在的相互作用,表面活性剂混合体系通常比单一表面活性剂更能降低溶液的表面能,该现象称为协同效应或复配增效^[1,2]。由于多元体系组成复杂,迄今仅能用正规溶液理论导出的非理想性参数(又称分子相互作用参数βs)来表征^[3-5],βs愈负,复配增效效果愈好。但如何从分子水平去理解βs至今尚不清楚。本文用二维晶格模型得出协同效应可用溶液表面层的分子交换能来描述,并推导出由βs计算该交换能的相应公式。 相似文献
993.
994.
A concise synthesis of α‐Man1 → 2‐α‐Man1 → 3‐(α‐Man1 → 6)‐α‐Man1 → 2‐α‐Man1 → 2‐α‐Man1 → 2‐Man, the antigenic factor 4 existing in Candida albicans, was achieved via TMSOTf promoted condensation of the corresponding acylated tetrasaccharide donor with the trisaccharide acceptor. 相似文献
995.
996.
Dong Weiwei Yang Beifang Fu Zhengping Wang Zhen Yang Yingling Zuo Jian 《化学物理学报(中文版)》2005,18(3):395-400
ZnO-MgO nanocomposite was prepared by glycine nitrate combustion method.Its photoluminescence property, the structure and annealing temperature dependence was studied by XRD, FTIR and SEM. The results show that the photoluminescence property of ZnO-MgO nanocomposite is greatly improved compared with that of pure ZnO. Under 325 nm laser excitation, the emission spectra of the 900 ℃ treated composite sample had an obviously enhanced ultraviolet (UV) band centered at 385 nm at room temperature. The luminescence intensity of the UV band became stronger with the increase of annealing temperatures and reached a maximum at 900 ℃ but decreased at 1000 ℃. The photoluminescence intensity was mainly affected by the grain size, the crystallization and the action between ZnO and MgO nanoparticles. In addition, an appropriate G/N value was favorable for improving the UV-PL properties of the nanocomposite samples. 相似文献
997.
Optical Review - Traditional phase measurement profilometry adopts divergent illumination to obtain the height distribution of a measured object accurately. However, the mapping relation between... 相似文献
998.
Yang Shi Jing Wan Gui-Xian Liu Tong-Tong Zuo Yue-Xian Song Prof. Dr. Bing Liu Prof. Dr. Yu-Guo Guo Prof. Dr. Rui Wen Prof. Dr. Li-Jun Wan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(41):18277-18282
Unstable electrode/solid-state electrolyte interfaces and internal lithium dendrite penetration hamper the applications of solid-state lithium-metal batteries (SSLMBs), and the underlying mechanisms are not well understood. Herein, in situ optical microscopy provides insights into the lithium plating/stripping processes in a gel polymer electrolyte and reveals its dynamic evolution. Spherical lithium deposits evolve into moss-like and branch-shaped lithium dendrites with increasing current densities. Remarkably, the on-site-formed solid electrolyte interphase (SEI) shell on the lithium dendrite is distinctly captured after lithium stripping. Inducing an on-site-formed SEI shell with an enhanced modulus to wrap the lithium precipitation densely and uniformly can regulate dendrite-free behaviors. An in-depth understanding of lithium dendrite evolution and its functional SEI shell will aid in the optimization of SSLMBs. 相似文献
999.
Guangyi Leng Yanhua Zuo Jiahui Hu Fei Yu Wanhui Liu 《Biomedical chromatography : BMC》2020,34(10):e4912
Fulvestrant (‘Faslodex’), an estrogen receptor antagonist, is available for the treatment of advanced breast cancer. The oil-based vehicle of Faslodex can lead to various adverse effects. A novel fulvestrant microcrystal (aqueous suspension) was developed in this study to eliminate these adverse effects. A sensitive and robust liquid chromatography tandem mass spectrometry method was developed and validated for the determination of fulvestrant in rat plasma using supported-liquid extraction. The separation of fulvestrant was achieved on an Agilent SB-C18 column (2.1 × 50 mm, 3.5 μm) with isocratic elution using fulvestrant-d3 as internal standard. Mass spectrometric detection was conducted in negative multiple reaction monitoring mode. Ion transitions were at m/z 605.5 → 427.5 for fulvestrant and m/z 608.5 → 430.5 for fulvestrant-d3. The excellent linearity was demonstrated over the range 0.05–100.0 ng/ml (r2 = 0.99). The lower limit of quantitation was 0.05 ng/ml, which was superior to that reported in literature The method validation was evaluated by selectivity, accuracy, precision, recovery and matrix effect in agreement with the US Food and Drug Administration guidance. The method was successfully applied to a pharmacokinetic study of a novel fulvestrant microcrystal in rats after intramuscular administration. It revealed that the rate of absorption increases and the extent of absorption is constant with a decrease in microcrystal diameter. 相似文献
1000.
Thermal performances of saturated porous soil during freezing process using lattice Boltzmann method
Hu Yiran Zuo Donghao Zhang Yaning Xu Fei Li Bingxi Liang Shuang 《Journal of Thermal Analysis and Calorimetry》2020,141(5):1529-1541
Journal of Thermal Analysis and Calorimetry - A stochastic growth method for generating the porous soil structure is proposed, and an enthalpy-based lattice Boltzmann phase transition model is... 相似文献