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41.
推导了描述调频激光受激布里渊散射的耦合波方程和准静态近似下增益因子的表达式,分析了啁啾脉冲的散射过程,讨论了泵浦激光和斯托克斯信号光率调制方式,带宽对泵浦光能量抽取效率和斯托克斯光脉冲波形的影响。 相似文献
42.
In this paper, the HMO model of scalar field in medium is presented using the general covariant classical theory of scalar field in medium, which is regarded as a curved space-time represented by optical metric model (OMM) and the case of self-focusing is discussed. 相似文献
43.
QIN Yuwen GE BaozhenCHEN Ximing ZHANG Yimol JIAN Shuisheng 《Chinese Journal of Lasers》1997,6(2):122-130
l.IntroductionJointtransformcorrelation[1]hasbeeninvestigatedwidelyinrecentyears[2~4]be-causeitsreferenceimagesandobjectimagescanbeuPdatedinreal-time[5J.Nonlinearjointtransformcorre1ationtheoretica1ana1ysis[']showsthatcomparedwiththelinearjointtransformcorrelation,non1inearjointtransformcorrelationcanproducemorehighautcacorre1ationPeakintensity,andthelargerPeaktosideloberatiothataregoodforelectronicdevicestodetectandana]yze.Onthebasisofthemodu1ationprincipleana1ysisoftheliq-uidcrysta11ightva… 相似文献
44.
Melandrium Roehl.中国有30余种.1980年出版的“新疆植物检索表”第二册收载了3种,“新疆植物名录”中收载了8种,“中国高等植物图鉴补编”(1:319,1982)收载了9种,作者把这一类群并入蝇子草属Silene L内,本文在对Melandrium和Silene两属的分类研究上做了形态学、孢粉学以及数值定量分析等方面的工作,认为把Melandrium并入Silene中欠妥(这一问题在另一篇文章中已讨论)。故仍持把这两个属分立对待的观点。本文按现行新疆维吾尔自治区的行政范围进行整理研究,共收载11种,其中发现全国分布新记录1种——M.tenellum Tolm.新疆分布新记录1种——M.noctiflo-rum(L.)Fries。本文阐明了新疆境内女娄菜属植物的生态、地理分布特点。指出新疆境内本属植物的区系地理成分主要是亚洲中部的草原和山地成分。 相似文献
45.
烷氧基取代金属酞菁的合成及其吸收光谱性质 总被引:10,自引:0,他引:10
合成了6种烷氧基取代的酞菁化合物,并进行了元素分析.研究了它们在溶液和薄膜中的吸收光谱性质. 相似文献
46.
Yingshu Feng Congyong Sun Emmanuel Omari‐Siaw Yuan Zhu Shanshan Tong Jinyi Wan Jiangnan Yu Ximing Xu 《Biomedical chromatography : BMC》2016,30(3):432-439
For quantitative and other related bioactive studies of hydnocarpin, there is a need to establish an efficient, specific and sensitive analytical method (in vitro and in vivo). In this paper, an efficient HPLC method has been established and validated to analyze hydnocarpin in a nanomicelle formulation for the first time. Various chromatographic conditions for in vitro and in vivo determinations were investigated, with the application examined by pharmacokinetics and tissue distribution studies. The analysis was carried out using an HPLC system with a Waters symmetry C18 column (4.6 × 150 mm, 5 µm) at 25°C with a detecting wavelength of 342 nm. Eluting at a rate of 1.0 mL/min, a 65% methanol and 35% acetic acid solution (0.1%) served as the mobile phase for the in vitro determinations while a 62% methanol and 38% acetic acid solution (0.1%) was used for in vivo analysis with isoliquiritigenin as internal standard. The established in vitro linearity range for hydnocarpin was 0.2–20 µg/mL (R2 = 0.9996), with the biological (in vivo) samples following the same trend. The accuracy of the method was >99% (in vitro) and 92.4–105.3% (in vivo). Also, the precision met the acceptance criterion. These results indicate that the established method exhibited high specificity, accuracy, linearity and precision. Additionally, this efficient HPLC method was applied to pharmacokinetics and tissue distribution studies. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
47.
The effectiveness of borneol on pharmacokinetics changes of four ginsenosides in Shexiang Baoxin Pill in vivo
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Li Xiang Shuping Wang Xiaojun Liu Ling Yang Jianfei Tao Zhongliang Chen Changsen Zhan Ximing Huang Runhui Liu Weidong Zhang 《Biomedical chromatography : BMC》2014,28(3):419-427
Shexiang Baoxin Pill (SBP) is a traditional Chinese medicine, widely used for cardiovascular diseases in the clinic. Ginsenosides are important effective components in SBP, but their pharmacokinetic characteristics are still not known. In this paper, we studied the pharmacokinetics of ginsenoside Rb1, Rc, Re and Rg1 in SBP and investigated the effect of borneol on the pharmacokinetic characteristic of ginsenosides based on an Agilent G6410A triple quadrupole LC/MS system. Results showed that the pharmacokinetic parameters of ginsenoside Rb1, Rc, Re and Rg1 in rat plasma after oral administration of SBP are significantly different with oral administration of SBP without Borneolum Syntheticum. Plasma pharmacokinetic profiles after oral administration of ginsenoside Rb1, Rc, Re, Rg1 and co‐administration with borneol at three different ratios (10:1, 1:1 and 1:10 ginsenoside vs borneol, w/w) were also determined. It was demonstrated that borneol can elevate the plasma concentration of ginsenosides after co‐admininstration. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
48.
49.
The stability and phase behavior of acrylamide-based emulsions, prepared with surfactants consisting of lipophilic Span80 and hydrophilic OP10, before or after polymerization were investigated. The research results indicated that the phase separation behavior of the W/O-type emulsions is related to the toluene/water ratio. When the water volume fraction was larger, the phase separation mechanism was mainly a penetration of aqueous molecules from the dispersed-phase droplets. When the water volume fraction was smaller, the phase separation mechanism was mainly a sedimentation of the separated aqueous droplets. At a fixed toluene/water ratio, the emulsion stability and the emulsion type are related not only to the ratio of the two surfactants but also to the acrylamide concentration, and the effect of increasing acrylamide concentration on the character of the emulsions is similar to that of increasing OP10 mass fraction (increasing HLB value), which determines the corresponding relationship between acrylamide concentration and HLB value in the most stable emulsion system. To obtain the most stable emulsion at a fixed acrylamide concentration, the emulsion with higher acrylamide concentration needs a lower HLB value for the emulsion systems. 相似文献
50.
用氢化物发生法测定水中砷已有很多报道,本文用类似古蔡氏法测砷的氢化物发生装置,使AsH3与涂在滤纸上的HAuCl4反应,生成不溶于水的AuAs沉淀,固定蓝紫色圆形斑点的表面积,用纸上双波长分光光度技术测定吸光度。本方法灵敏度高,精密度较好,设备简单,操作方便,检出限为10ng/ml,相对标准偏差小于4%。 相似文献