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991.
The aim of this research work was to clarify the role of the mixed emulsifier in the structure formation and water binding
mode in the case of o/w creams prepared with different surfactants. The swelling behavior of mixed emulsifiers was examined
by means of direct investigation methods such as transmission electron microscopy (TEM) and X-ray diffraction. The detailed
structure image of the creams was created with the help of the latter. The influence of the structure of the hydrophilic gel
phase, and the structural changes during storage were studied with rheological methods. On the basis of the results, it can
be stated that the investigated creams had different structures from those mentioned in the literature: surfactant did not
create a mixed bilayer with the structure to furnish fatty amphiphile; instead, micelles were formed. These results correlated
well with the results of the rheological tests. 相似文献
992.
Highly ordered mesoporous bioactive glasses with superior in vitro bone-forming bioactivities 总被引:3,自引:0,他引:3
993.
毛细管电泳质谱联用技术及其应用 总被引:9,自引:0,他引:9
本文介绍了用于毛细管电泳质谱联用仪器的多种接口技术,描述了CZE,CIEF,CGE,MEKC和CITP等毛细管电泳技术和四极质谱,离子阱质谱,傅 叶变换离子回旋共振质谱,飞行时间质谱,磁质谱,解吸质谱等联用的现状及发展前景,对近年来CE-MS在酶解产物。蛋白质和肽,核苷酸,药物及代谢产物等领域中的应用作了详细述评。 相似文献
994.
Guangqiang Xu Li Zhou Chengdong Lv Mo Xian Qinggang Wang 《Journal of Saudi Chemical Society》2019,23(7):896-902
A metal-free, acid-free, direct and eco-friendly nitration methodology has been developed. A tert-butyl nitrite efficiently promotes the direct CH nitration of electron-rich arenes with good to excellent yields and regioselectivities. The practical utility of this protocol has been demonstrated in gram-scale nitration of crown ether and mono nitration of Sesamin. A plausible free radical mechanism is proposed based on detailed experimental observations. 相似文献
995.
FT-IR and Raman spectroscopic study of hydrated rubidium (cesium) borates and alkali double borates 总被引:1,自引:0,他引:1
Zhu Lixia Yue Tao Wang Jiang Gao Shiyang 《Russian Journal of Inorganic Chemistry》2007,52(11):1786-1792
FT-IR and Raman spectra of five hydrated alkali borates and five hydrated alkali double borates have been recorded at room
temperature in the range 400 to 4000 cm−1, and analyzed. Fundamental vibrational modes have been identified and assignments tentatively made in comparison with the
work of Janda and Heller, and Li Jun.
The text was submitted by the authors in English. 相似文献
996.
Poly ionic liquid 1-ethyl 3-(2-methacryloyloxy ethyl) imidazolium iodide (PEMEImI) as a single-ion conductor was designed and synthesized. When appropriate amount of suitable plasticizers, I2 and polyacrylonitrile (PAN) were incorporated into it, the complex formed gel polymer electrolyte. Chemical structure, thermal behavior and ionic conductive properties of the gel polymer electrolyte were investigated by Raman spectra, UV-Vis spectra, differential scanning calorimetry (DSC), and complex impedance analysis, respectively. For the new gel polymer electrolyte, the ionic conductivity of about 1 × 10−3 S cm−1 at room temperature was achieved. 相似文献
997.
998.
Polymer electrolyte systems were prepared for the first time by dissolution of amidomagnesium chlorides in poly(ethylene oxide),
(PEO). For the preparation, solutions of (hexamethyldisilylamido)magnesium chloride, (dimethylpyrrolyl)magnesium chloride,
(diisopropylamido)magnesium chloride, piperidinomagnesium chloride and morpholinomagnesium chloride were chosen. The composition
of these polymer electrolyte systems corresponds to the general formula R2NMgCl·P(EO)n·THF. Most work has been done with the system (hexamethyldisilylamido)magnesium chloride in PEO, (Me3Si)2NMgCl·P(EO)n·THF, with n= 3, 4, 5, or 7. The electrolytes have a soft rubber-like consistency. At 30 °C, electrical conductivities of 10−6–10−5 S/cm were found. The conductivities were measured in the temperature range 20–60 °C. Within this temperature range a linear
dependence of the logarithms of the conductivity on the inverse temperature was found and activation energies for the conducting
process of 30–60 kJ/mol were calculated. Using those polymer electrolytes with a high content of the amidomagnesium compound,
a reversible magnesium deposition takes place by cathodic reduction at potentials below −1.9 V vs. a Ag/AgCl reference electrode.
These polymer electrolytes were found to be stable against oxidation up to about −0.3 V vs. Ag/AgCl.
Electronic Publication 相似文献
999.
1000.
本文报道了同时测定钴和镍的一种方法.在 0.01mol/L NH_3·H_2O-0.01mol/LNH_4Cl-3.0×10~(-5)mol/L安息香缩氨基硫脲(BTSC)溶液中,钴(Ⅱ)和镍(Ⅱ)均产生非常灵敏的还原波,其峰电位分别是:-0.94和-0.75V(vs.SCE),峰电流与钴和镍的浓度分别在2.0×10~(-8)~1.0×10~(-6)和1.0×10~(-8)~8.0×10~(-7)mol/L范围内成直线关系,该方法用于测定水中痕量钴和镍,相对标准偏差分别为1.4~2.0%和2.1~2.5%,回收率分别在98.0%~101.8%和97.9%~102.1%之间. 相似文献