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191.
S. Talegaonkar G. Mustafa S. Akhter Z. I. Iqbal 《Journal of Dispersion Science and Technology》2013,34(5):690-701
The objective of the present investigation was to design a thermodynamically stable and dilutable nanoemulsion formulation of AT-Ca with minimum surfactant concentration that could improve its solubility as well as its oral bioavailability. The composition of optimized nanoemulsion formulation was Sefsol 218 and oleic acid (1:1) 10% w/w, as an oil phase, Tween-20 (19% w/w) as a surfactant, Carbitol (19% w/w) as a cosurfactant and distilled water (52% w/w) as an aqueous phase, containing 10 mg of AT. The optimized formulation showed higher% drug release (99.34%), lower droplet size (42.8 ± 0.42 nm) with low polydispersity index (0.237 ± 0.012), less viscosity (27.51 ± 1.01 cP) and infinite dilution capability. In vitro drug release from the nanoemulsion formulations was highly significant (p < 0.01) as compared to drug suspension. 相似文献
192.
M. J.B. Alam A. K. Dikshit M. Banerjee I. Reza A. M. Rahman 《Journal of Dispersion Science and Technology》2013,34(6):843-849
From this study it was evident that outer peristaltic parts of waste tire granules gave the highest removal. Film and pore diffusions are the major factors controlling rates of sorption from solution by porous adsorbents. For sorption of 2,4‐D on waste tire rubber granules, the sorption rate coefficient of second‐order kinetic equation was utilized indirectly to determine the rate‐limiting step. The diffusion coefficient lies in the scale of 10?8 cm2/s, and the pore diffusion coefficient is in the range of 10?9–10?10 cm2/s. So both film and pore diffusion are rate limiting. Considering external mass transfer from fluid to particle, using the effect of initial concentration, and using the effect of adsorbent size, no conclusion was reached regarding rate‐controlling steps. It is apparent from the study that external mass transfer (film diffusion) as well as intra‐particle diffusion (pore diffusion) play significant roles in the sorption process for 2,4‐D removal from water onto rubber granules. 相似文献
193.
针对现代数字化战车电气与电子系统技术复杂、各分系统关联程度高、维修保障困难等问题,设计了一种基于CAN总线的数字化战车自动测试系统;整体设计基于模块化思想,充分利用车载备用总线,综合运用了DSP+FPGA控制处理技术、AFPN智能故障诊断技术,能够对车载电气与电子系统进行分系统独立测试和全系统联合检测,具有快速故障定位能力和拓扑适应能力;采用适配器与上位机测试软件的分体式设计,实现了平台物理资源复用。应用表明,该系统能够较好的适用于现代数字化战车的维修保障,使用方便,故障诊断快速有效。 相似文献
194.
为了评估某型机载瞄准系统的精度,根据飞行试验参数测试需要,提出了通过图像测量与DGPS融合处理方法进行瞄准精度评估的试验方案。该方案利用飞行试验获取的图像数据与其他测量数据相结合,建立精度评估的方法,该评估方法在该机载武器瞄准系统精度评估得到应用,并且可在同类试验课题中推广应用。 相似文献
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197.
Lianfang Chen Hongmei NieGuangbo Zhang Fuwen GongYuzhu Yang Chengbin GongKun Xiao 《Tetrahedron letters》2014
This Letter aimed to develop an efficient method for the determination of cyanide ion (CN−). A novel colorimetric chemosensor 4-[(1E)-2-(4-hydroxyphenyl)ethenyl]-1-allylpyridinium bromide (HPEAPB) was synthesized. HPEAPB displayed good selectivity toward CN− over other competing anions in ethanol. A color change from yellow to red was immediately observed upon the addition of CN− and the limit of detection (LOD) was 3.4 × 10−6 mol L−1. The sensing mechanism was discussed by UV–vis, 1H NMR titration, and a comparison study. Colorimetric test paper for CN− was prepared by attaching HPEAPB to a chromatography paper, which could be used to detect CN− in environmental samples as simply as a pH-indicator paper for pH value. The LOD of the test paper for CN− was 2.0 × 10−4 mol L−1. This detection method for CN− has potential applications in cyanide ion containing fields by combination of rapid and real-time advantages. 相似文献
198.
为寻找具有更高生物活性、更环保的新农药杀菌剂,基于杀菌剂氟咯菌腈设计并合成了10个新型吡唑联吡咯类杂环化合物,以吡唑环代替氟咯菌腈上原有的苯环,以期提高其杀菌活性.采用1H NMR,FTIR,单晶X射线衍射、元素分析和熔点测定等测试手段对目标化合物及其中间体的结构进行了表征与确认,并通过挥发法培养得到了6个目标化合物的单晶.还对其中6个化合物进行了生物活性测试,测试结果表明各化合物对水稻纹枯病、黄瓜灰霉病、黄瓜霜霉病均表现出一定的抑菌效果,可作为先导化合物对其结构进行深入的研究,为新农药杀菌剂的开发提供了理论支持. 相似文献
199.
Quantitative analysis and pharmacokinetics study of tigecycline in human serum using a validated sensitive liquid chromatography with tandem mass spectrometry method
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Jiao Xie Taotao Wang Xue Wang Xiaoliang Cheng Haiyan Dong Yan Wang Xiaowei Zheng Liang Zhou Jianfeng Xing Yalin Dong 《Journal of separation science》2014,37(12):1396-1403
Tigecycline, a novel intravenously administered glycylcycline antibiotic, currently plays a key role in the management of complicated multiorganism infections. However, current liquid chromatography with tandem mass spectrometry methods briefly describe parameters and the only reported internal standard was sometimes difficult to obtain. In our study, an updated liquid chromatography with tandem mass spectrometry method for the quantitative analysis of tigecycline in human serum was developed. Sample preparation involved precipitation with 20% trichloroacetic acid. Chromatographic separation of tigecycline and tetracycline (internal standard) was achieved on a Hypersil GOLD C18 column using gradient elution. The selected reaction monitoring transitions were performed at m/z 586.1→513.2 for tigecycline and m/z 445.1→410.2 for tetracycline. The assay was linear over the concentration range of 5–2000 ng/mL. The intra‐ and interday precisions at three concentration levels (10, 100, and 1600 ng/mL) were <15% and their accuracies were within the range of 95.1–106.1%. The mean recovery ranged from 94.3 to 105.6% and the matrix effect from 92.1 to 97.6%. Tigecycline was stable under all tested conditions. This validated method was successfully applied to a pharmacokinetic study in critically ill patients. The data demonstrated that our method allows quantification of tigecycline in serum in a quick and reliable manner for widespread application. 相似文献
200.
Gang Cao Qiyang Shou Qinglin Li Jianping Jiang Xiaocheng Chen 《Journal of separation science》2014,37(21):3090-3093
The processing procedure can alter the nature and chemical transformation of traditional Chinese medicine to accommodate different clinical dispensing and preparation requirements. In this study, static headspace‐multicapillary column with gas chromatography coupled to ion mobility spectrometry was developed for the rapid and sensitive discrimination of crude and processed traditional Chinese medicine. Using Radix Paeoniae Alba as a traditional Chinese medicine model, the combined power of this approach was illustrated by classifying the crude and processed Radix Paeoniae Alba samples into two main categories. The contents of the main components in Radix Paeoniae Alba varied significantly. The established method could promote the use of ion mobility spectrometry in intrinsic quality control and differentiation of herbal medicines from other processed products or preparations. 相似文献