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Development of a method using high‐performance liquid chromatographic fingerprint and multi‐ingredients quantitative analysis for the quality control of Yangxinshi Pian 下载免费PDF全文
Yerui Li Kai Yang Bowen Liu Ye Jin Xuesong Liu Zuolin Jiang Lianjun Luan Yongjiang Wu 《Journal of separation science》2015,38(17):2989-2994
A simple and reliable method of high‐performance liquid chromatography with diode array detection method was developed for fingerprint analysis and simultaneous determination of six compounds including puerarin, salvianolic acid B, berberine hydrochloride, palmatine chloride, dehydrocorydaline, and icariin in the Chinese medicine preparation Yangxinshi Pian. The separation was performed on an Agilent Eclipse XDB‐C18 reserved‐phase column (250 mm × 4.6mm I.D., 5 μm) using gradient elution with 50 mmol/L monopotassium phosphate aqueous solution and methanol as mobile phase at a flow rate of 1.0 mL/min. The column operating temperature was set at 30°C, and the detection wavelength was 280 nm. The method was validated by linearity, precision, accuracy, stability, and recovery. For fingerprint analysis, 25 peaks were selected as the common peaks, and four kinds of similarities including cosine similarity (S), ratio of similarity (S′), projection content similarity (C), and content similarity (P) were applied to evaluate the quality consistency of different batches of Yangxinshi Pian. The results showed that the developed method was an efficient tool for quality evaluation of Yangxinshi Pian. 相似文献
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This paper undertakes a systematic treatment of the low regularity local wellposedness and ill-posedness theory in H^s and H^s for semilinear wave equations with polynomial nonlinearity in u and δu. This ill-posed result concerns the focusing type equations with nonlinearity on u and δtu. 相似文献
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We present a kind of solutions of D-equations in terms of what we have called a D-pair in this paper. Some properties of dimodules associated with D-pairs are discussed as well. 相似文献
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MiaoChangxing ZhangBo FangDaoyuan 《偏微分方程(英文版)》2004,17(2):97-121
We study global well-posedness below the energy norm of the Cauchyproblem for the Klein-Gordon equation in R^n with n≥3. By means of Bourgain‘s method along with the endpoint Strichartz estimates of Keel and Tao, we prove the H^s-global well-posedness with s<1 of the Cauchy problem for the Klein-Gordon equation. This we do by establishing a series of nonlinear a priori estimates in the setting of Besov spaces. 相似文献
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Gan Danyan 《数学年刊B辑(英文版)》1996,17(3):257-262
51.IntroductionOne0ftheinterestingproblemsneartheheartof4dimensionaltopologyistodecidewhich2-dimensionalhomology/homotoPyclasscanberepresentedbyasmo0thlyembedded2-sphereinagivensmooth4-dimensionalmanifold.ItwasRohlin[19]wh0pointed0utintheearly195Ostousthatnotevery2-dimensionalhthmology/hom0topyclasscanbesorepresented.TheimportanceoftheproblemwasexplainedbyKervaireandMilnorl11].Onedecadelater,theystartedthestudyin1961,followedbyBoardm..I1]?Wall[25]5Tri.t..m[23]tHsiangandSzczarba[1o],andRoh… 相似文献
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Wu Shaoping 《数学年刊B辑(英文版)》1996,17(2):245-256
The existence of at least two homoclinic orbits for Lagrangian system (LS) is proved, wherethe Lagrangian L(t,x,y) =1/2∑aij(x)yiyj-V(t, x), in which the potential V(t,x) is globallysurperquadratic in x and T-periodic in t. The Concentration-Compactness Lemma and Mini-max argument are used to prove the existences. 相似文献
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Acrylonitrile(AN) and maleic anhydride(MA) copolymer has been synthesized by radical polymerization using ammonium persulfate and sodium bisulfite as initiator.The pervaporation properties of the copolymeric membranes prepared have been investigated for the first time. The dependences of pervaporation characteristics on coplymer composition,feed concentration and operating temperature have been studied.In order to improve the separation properties of the copolymeric membranes,the membranes were hydrolyzed with 10 wt% soldium hydroxide or potassium hydroxide aqueous solution.The hydrolyzed membranes containing more than 0.069MA mol fraction showed higher tensile strength and separation properties than the original membranes. 相似文献
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Jiang Y Sun W Xu B Yan M Bahlawane N 《Physical chemistry chemical physics : PCCP》2011,13(13):5760-5763
Electrical conductivity of SnO(2)-based oxides is of great importance for their application as transparent conducting oxides (TCO) and gas sensors. In this paper, for the first time, an unusual enhancement in electrical conductivity was observed for SnO(2) films upon zinc doping. Films with Zn/(Zn + Sn) reaching 0.48 were grown by pulsed spray-evaporation chemical vapor deposition. X-Ray diffraction (XRD) shows that pure and zinc-doped SnO(2) films grow in the tetragonal rutile-type structure. Within the low doping concentration range, Zn leads to a significant decrease of the crystallite size and electrical resistivity. Increasing Zn doping concentration above Zn/(Zn + Sn) = 0.12 leads to an XRD-amorphous film with electrical resistivity below 0.015 ? cm at room temperature. Optical measurements show transparencies above 80% in the visible spectral range for all films, and doping was shown to be efficient for the band gap tuning. 相似文献