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101.
清开灵注射液中10种有效成分的同时测定及其质量相关性研究 总被引:1,自引:0,他引:1
采用HPLC-DAD-ELSD法,在最优波长(255 nm)下同时测定了清开灵注射液的10种有效成分,测定了不同厂家的15个批次清开灵注射液样品,进行了质量相关性分析.所建立的分析方法符合规定标准,所测样品中,不同厂家及同厂家不同批次样品间各组分的含量差异悬殊(RSD值范围为2.17%~65.54%).方法简便可靠,可用于清开灵注射液的质量控制.尽量多地控制这些已知的主要有效成分是保证清开灵注射液质量的关键. 相似文献
102.
Ardoint M Agus T Sheft S Lorenzi C 《The Journal of the Acoustical Society of America》2011,130(2):EL115-EL121
This study investigated the ability to use temporal-envelope (E) cues in a consonant identification task when presented within one or two frequency bands. Syllables were split into five bands spanning the range 70-7300 Hz with each band processed to preserve E cues and degrade temporal fine-structure cues. Identification scores were measured for normal-hearing listeners in quiet for individual processed bands and for pairs of bands. Consistent patterns of results were obtained in both the single- and dual-band conditions: identification scores increased systematically with band center frequency, showing that E cues in the higher bands (1.8-7.3 kHz) convey greater information. 相似文献
103.
We report a photoluminescence study of silicon nanoclusters deposited by laser ablation. This technique allows to obtain clusters with a reduced size dispersion. Taking advantage of that as well as of the possibility to tune selectively the cluster size relatively to the preparation parameters, we are able to make a fine correlation between the emission band and the corresponding emitting size. The photoluminescence band can be tuned in a wide spectral region spreading from the near ultraviolet to the near infrared depending on preparation conditions. The correlation with atomic force microscopy measurements provides a size dependence of the luminescence which is fully consistent with the quantum confinement interpretation. To our knowledge, we present here the first observation of a wide spectral range tuning of the emission bands of nanocrystalline silicon by using a dry technique compatible with clean vacuum processing. 相似文献
104.
GuangYuXU ChunHaoYANG BoLIU XiHanWU YuYuanXIE 《中国化学快报》2004,15(12):1403-1406
In a quest for better chelating therapy drugs for the treatment of intoxication by Fe, A1, or actinides, two new series of mixed catechol-bisphosphonate through amide linkage were synthesized. Benzyl group was used as protecting group to avoid the breakage of amide by acid hydrolysis or imcomplete reaction in silylation-dealkylation using bromotrimethylsilane. 相似文献
105.
以GC法测定瑞草油各组分时,采用20% PEG-20 M固定相,正葵醇为内标,柱温以每min 4℃从170℃升至210℃。四组分的方法回收率、变异系数(n=5)、及其线性浓度范围分别为:樟脑97.44±1.04%、9.0~130mg/mL;薄荷脑99.68±0.97%、28.0~40.0 mg/mL;水杨酸甲酯97.16±0.48%、4.0~6.0 mg/mL;水杨酸乙酯100.44±1.13%、4.0~6.0 mg/mL。经测定三批样品的结果表明,本法具有操作简单、快捷、准确等优点。 相似文献
106.
Marine Minier 《Designs, Codes and Cryptography》2017,82(1-2):117-129
Impossible-differential attacks are a very efficient form of cryptanalysis against block ciphers. In this paper, we improve the existing impossible-differential attacks against Rijndael-160 and Rijndael-224. 相似文献
107.
Victor Gonzalez Marine Cotte Gilles Wallez Annelies vanLoon Wout deNolf Myriam Eveno Katrien Keune Petria Noble Joris Dik 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(17):5675-5678
Rembrandt (1606–1669) is renowned for his impasto technique, involving his use of lead white paint with outstanding rheological properties. This paint was obtained by combining lead white pigment (a mixture of cerussite PbCO3 and hydrocerussite Pb3(CO3)2(OH)2) with an organic binding medium, but the exact formulation used by Rembrandt remains a mystery. A powerful combination of high‐angle and high‐lateral resolution x‐ray diffraction was used to investigate several microscopic paint samples from four Rembrandt masterpieces. A rare lead compound, plumbonacrite (Pb5(CO3)3O(OH)2), was detected in areas of impasto. This can be considered a fingerprint of Rembrandt's recipe and is evidence of the use of an alkaline binding medium, which sheds a new light on Rembrandt's pictorial technique. 相似文献
108.
Florian Tieves Sbastien Jean‐Paul Willot Morten Martinus Cornelis Harald vanSchie Marine Charlne Rene Rauch Sabry Hamdy Hamed Younes Wuyuan Zhang JiaJia Dong Patricia GomezdeSantos John Mick Robbins Bettina Bommarius Miguel Alcalde Andreas Sebastian Bommarius Frank Hollmann 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(23):7955-7959
109.
Dr. Victor Gonzalez Dr. Marine Cotte Dr. Frederik Vanmeert Dr. Wout de Nolf Prof. Koen Janssens 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(8):1703-1719
X-ray diffraction (XRD) mapping consists in the acquisition of XRD patterns at each pixel (or voxel) of an area (or volume). The spatial resolution ranges from the micrometer (μXRD) to the millimeter (MA-XRD) scale, making the technique relevant for tiny samples up to large objects. Although XRD is primarily used for the identification of different materials in (complex) mixtures, additional information regarding the crystallite size, their orientation, and their in-depth distribution can also be obtained. Through mapping, these different types of information can be located on the studied sample/object. Cultural heritage objects are usually highly heterogeneous, and contain both original and later (degradation, conservation) materials. Their structural characterization is required both to determine ancient manufacturing processes and to evaluate their conservation state. Together with other mapping techniques, XRD mapping is increasingly used for these purposes. Here, the authors review applications as well as the various configurations for XRD mapping (synchrotron/laboratory X-ray source, poly-/monochromatic beam, micro/macro beam, 2D/3D, transmission/reflection mode). On-going hardware and software developments will further establish the technique as a key tool in heritage science. 相似文献
110.
A new bidesmoside triterpenoid saponin,named stauntoside C1(1) has been isolated from Stauntonia chinensis.Its structure was established by means of spectral and chemical methods. 相似文献