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Jingcheng Hao Hanqing Wang Shuo Shi Runhua Lu Taotao Wang Ganzuo Li Haiying Sun 《中国科学B辑(英文版)》1997,40(3):225-235
By the orthogonal design, the optimal formation conditions for the middle-phase microemulsions in the system dioctadecyldimethylammonium
chloride (DODMAC)/ sodium dodecyl sulfate (SDS)/n-butanol/n-hep-tane/brine were obtained as follows: WDODMAC: WSDS = 1:4-1:5,C
π-butanol (%) = 11.0-12.0, andC
NaCl (%) = 3.25
Investigations have been made on the effects of the concentrations of NaCl and n-butanol (l.0%-14.0%), the ratios ofWDODMAC: to WSDS, and the kinds of alcohols (n-propanol, n-butanol, and n-pentanol) on the formation, the phase behaviour, the ultralow interfacial
tensions, the optimal salinity (S*), and the length of salinity (δS). Some rules and data were worked out about the formation and characteristics of the middle-phase
microemulsions. The mi-crostructures of the middle-phase microemulsions were also studied by using FT-IR, ESR, and freeze
fracture electron microscopy techniques. The results from the three methods show that the microstructures of the middlephase
mi-croemulsions undergo the change from O/W to bicontinuous (B.C.) and to W/O. The distribution rule of the orga-nized molecule
assemblies in the middle-phase microemulsions is conducible to constructing the model of microemulsion systems, to recognizing
the microstructures of the middle-phase microemulsions, and to setting forth the relationship between the microstructures
and macro-properties of rnicroemulsions.
Project supported by the Niltional Natural Science Foundation of China and the Chinese Postdoctoral Science Foundation. 相似文献
3.
[reaction: see text] A stereoselective synthesis of (-)-ilimaquinone (4) is presented. The synthetic strategy is based on a novel radical decarboxylation and quinone addition methodology that produces quinone 7 from reaction of thiohydroxamic acid derivative 8 with benzoquinone (9). Final functionalization of 7 to ilimaquinone (4) is achieved by exploring the electronic effects of the residual thiopyridyl group. 相似文献
4.
5.
Kezhen Yang Taotao Lv Jiaojuan Wu Xudong Zhang Yanjun Xue Pengcheng Yu Qingguo Liu 《Biomedical chromatography : BMC》2022,36(5):e5338
Hypertension affects multiple organs in the body during the development of the disease. The antihypertensive effect of acupuncture has been confirmed. How the protective effect of electroacupuncture on the renal cortex of the spontaneously hypertensive rat (SHR) is achieved has not yet been determined. The purpose of this study was to understand the impact of electroacupuncture on the blood pressure of SHRs and the impact on metabolites in the renal cortex, looking for potential differential metabolites and then proceeding to the next step of exploratory research. The experimental animals were divided into four groups: control group, model group, electroacupuncture group and losartan potassium group. Electroacupuncture on bilateral Taichong (LR3) and Zusanli (ST36) lasted for 3 weeks, and the renal cortex was collected for metabonomics research. UHPLC–MS was used to analyze the changes in the metabolic spectrum of renal cortex tissue. The results showed that electroacupuncture can significantly reduce the blood pressure of SHRs. A total of 12 metabolites changed significantly in the comparison between each group and the model group.The possible mechanism is that the primary bile acid biosynthesis, bile secretion, tryptophan metabolism and other metabolic pathways affect the renal cortex. 相似文献
6.
Quantitative analysis and pharmacokinetics study of tigecycline in human serum using a validated sensitive liquid chromatography with tandem mass spectrometry method 下载免费PDF全文
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
8.
正Dear Editors,Active Galactic Nuclei(AGNs)are very effective tools to study the environment both intrinsic to the central black holes of galaxies[1],or absorbing gas distributed along the sight lines.Recently,numerous highly ionized,local(z=0)metal absorption lines were detected in the X-ray spectra of background AGNs[2],providing an important method in probing hot gas and its content in and around our Galaxy.Of particular 相似文献
9.
Taotao Feng Wenliang Ji Yue Zhang Fei Wu Qiao Tang Huan Wei Prof. Lanqun Mao Prof. Meining Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(52):23651-23655
Electrochemical sensing performance is often compromised by electrode biofouling (e.g., proteins nonspecific binding) in complex biological fluids; however, the design and construction of a robust biointerface remains a great challenge. Herein, inspired by nature, we demonstrate a robust polydopamine-engineered biointerfacing, to tailing zwitterionic molecules (i.e., sulfobetaine methacrylate, SBMA) through Michael Addition. The SBMA-PDA biointerface can resist proteins nonspecific binding in complex biological fluids while enhancing interfacial electron transfer and electrochemical stability of the electrode. In addition, this sensing interface can be integrated with tissue-implantable electrode for in vivo analysis with improved sensing performance, preserving ca. 92.0% of the initial sensitivity after 2 h of implantation in brain tissue, showing low acute neuroinflammatory responses and good stability both in normal and in Parkinson′s disease (PD) rat brain tissue. 相似文献
10.
采用糖球模板法结合热致相分离技术,制备了孔径尺寸、内连通度及孔隙率高度可控的左旋聚乳酸(PLLA)支架材料,并通过扫描电镜(SEM)、红外光谱(FTIR)以及示差扫描量热法(DSC)对其空间结构及性能进行了系统研究.支架材料孔径从50μm到800μm及内连通孔径从10μm到200μm连续可调,微观孔壁结构根据不同溶剂可形成各异的微纳米结构.支架的制备对PLLA化学结构无显著影响,但相分离过程会不同程度地降低PLLA的结晶度. 相似文献