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61.
Jianqiang Zhang Jijiang Ge Anzhou Feng Ping Jiang Ruidong Li 《Journal of Dispersion Science and Technology》2013,34(11):1589-1595
To solve the problem of high pressure of water injection in low permeability reservoirs, a high concentration of surfactant system was developed in this article. With the solubilization of oil in aqueous surfactant solution as a criterion, a formula was screened from anionic and nonionic-anionic surfactants, and the optimal depressurized system was obtained as follows, 13.3% surfactant HEX +2.23% n-propanol +4.47% n-butanol, the solubilization capability being up to 0.66 g/g. This system had good salt tolerance, and it exhibited water external microemulsion in the range of of 1 to 200 g/L NaCl. Core flooding results show that this high concentration of surfactant system formed water external microemulsion with the residual oil in the core, reducing the displacement pressure over 35%. Meanwhile, the effects of concentration and injection volume on depressurization were also investigated. It is indicated that a good depressurization effect was achieved after injecting 1 pore volume of the system with the salt concentration of 100 g/L. 相似文献
62.
As a kind of ammonia‐oxidizing bacteria, Nitrosomonas europaea (N. europaea) was chosen as a research model to study the alteration of cell membrane in the presence of tourmaline and biodegradation of acetochlor. atomic force microscopy images reveal that the presence of tourmaline substantially changes the structure of the outer membrane of the cell responsible for the cell permeability. SEM images show that the introduction of tourmaline makes the cell lose its ability to resist lysozyme owing to the damages. The fluorescence polarization has shown a significant decrease in membrane fluidity and the increase of permeability of cell membrane. Ca2+ and Mg2+ was measured using inductively coupled plasma mass spectrometry and was found in the supernatant from the cells treated by tourmaline. Tourmaline can improve the efficiency of biodegradation of acetochlor for N. europaea. It is proposed that the cell permeability is slightly increased, and the absorbability of nutrition from the medium becomes easier. As a result, N. europaea grows faster in the presence of tourmaline than the native cells. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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目的 评价低渗温热腹腔灌注化疗治疗恶性腹腔积液的疗效及不良反应。方法 行腹腔穿刺置单腔中心静脉导管,外接引流袋,记录腹水引流量,当日排放腹水1 500ml 后,予加热至43~45℃注射用双蒸馏水1 000ml 行腹腔灌注,次日重复放液1 500ml,再予加热至43~45℃注射用双蒸馏水1 000ml 行腹腔灌注,并于灌注后腹腔注入顺铂60mg、氟尿嘧啶500mg 并封管,治疗期间常规给予简单水化、对症止吐等治疗。结果 31 例恶性腹腔积液患者共完成低渗温热腹腔灌注化疗42 周期,完全缓解7例,部分缓解15,稳定5 例,进展4 例,完全缓解+ 部分缓解占70.97%。中位进展时间(TTP)3.6个月(2~9 个月), 中位生存期(MST)5.6 个月。毒副反应以消化道反应为主。结论 低渗温热腹腔灌注化疗治疗恶性腹腔积,在延长患者的生存期、提高生活质量方面效果较好,临床上可推荐应用。 相似文献
65.
meso‐Ester and Carboxylic Acid Substituted BODIPYs with Far‐Red and Near‐Infrared Emission for Bioimaging Applications 下载免费PDF全文
Yong Ni Prof. Lintao Zeng Dr. Nam‐Young Kang Prof. Kuo‐Wei Huang Prof. Liang Wang Zebing Zeng Prof. Young‐Tae Chang Prof. Jishan Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(8):2301-2310
A series of meso‐ester‐substituted BODIPY derivatives 1–6 are synthesized and characterized. In particular, dyes functionalized with oligo(ethylene glycol) ether styryl or naphthalene vinylene groups at the α positions of the BODIPY core ( 3 – 6 ) become partially soluble in water, and their absorptions and emissions are located in the far‐red or near‐infrared region. Three synthetic approaches are attempted to access the meso‐carboxylic acid (COOH)‐substituted BODIPYs 7 and 8 from the meso‐ester‐substituted BODIPYs. Two feasible synthetic routes are developed successfully, including one short route with only three steps. The meso‐COOH‐substituted BODIPY 7 is completely soluble in pure water, and its fluorescence maximum reaches around 650 nm with a fluorescence quantum yield of up to 15 %. Time‐dependent density functional theory calculations are conducted to understand the structure–optical properties relationship, and it is revealed that the Stokes shift is dependent mainly on the geometric change from the ground state to the first excited singlet state. Furthermore, cell staining tests demonstrate that the meso‐ester‐substituted BODIPYs ( 1 and 3 – 6 ) and one of the meso‐COOH‐substituted BODIPYs ( 8 ) are very membrane‐permeable. These features make these meso‐ester‐ and meso‐COOH‐substituted BODIPY dyes attractive for bioimaging and biolabeling applications in living cells. 相似文献
66.
《中国化学快报》2020,31(6):1665-1669
Recent studies have shown impressive transport behaviors of water and ions within lamellar MXene membranes,which endows great promise in developing advanced separation application based high performance MXene membranes.However,most of the researches focused on modification of MXene nanoflakes and optimizing interlayer distance,leaving the impact of membrane fabrication process marginal.In this work,we studied the water flux of membranes made by vacuum filtration using delaminated MXene nanoflakes as the building-blocks.Our results show that the water permeability is extremely sensitive to the process,especially at the drying process,loading and deposit rate of nanoflakes(the feeding concentration).We find that the voids from less ordered stack rather than in-plane defects and interlayer galleries contribute to the large water permeability.The voids can be effectively avoided via deposition of MXene nanoflakes at a slow rate.Manipulating the stack of MXene nanoflakes during vacuum filtration and drying are critical for development of MXene membranes with desired performance for water permeation. 相似文献
67.
In order to improve the performance and durability of polymer electrolyte fuel cells (PEFCs), various improvements in the microstructures of cathode catalyst layers (CLs) were initiated in the early 1990s. More recent advances in CL materials are highlighted, including carbon supports for improved accessibility of Pt nanoparticles (NPs), adsorption of ionomer on the Pt surface, high-oxygen-permeability ionomers, corrosion resistance of mesoporous and microporous carbons, and conductive ceramic supports with a fused-aggregate network structure. These approaches are summarized as stepwise improvements. The influences of the support structure on the distribution of Pt NPs and ionomer are reviewed, as well as their effects on performance and durability. These approaches for carbon supports are extended to conductive ceramic supports and the unique advantages are discussed. 相似文献
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69.
Mimi Wan Qi Wang Xiaoyun Li Bo Xu Dan Fang Ting Li Yueqi Yu Leyi Fang Yue Wang Meng Wang Fenghe Wang Chun Mao Jian Shen Jia Wei 《Angewandte Chemie (International ed. in English)》2020,59(34):14458-14465
Limited tumor permeability of therapeutic agents is a great challenge faced by current cancer therapy methods. Herein, a kind of near infrared light (NIR)‐driven nanomotor with autonomous movement, targeted ability, hierarchical porous structure, multi‐drugs for cancer chemo/photothermal therapy is designed, prepared and characterized. Further, we establish a method to study the interaction between nanomotors and cells, along with their tumor permeability mechanism, including 2D cellular models, 3D multicellular tumor spheroids and in vivo models. In vivo tumor elimination results verify that the movement behaviour of the nanomotors can greatly facilitate them to eliminate tumor through multiple therapeutic methods. This work tries to establish systematic research and evaluation models, providing strategies to understand the relationship between motion behaviour and tumor permeation efficiency of nanomotors in depth. 相似文献
70.
High diffusion barrier and piezoelectric nanocomposites based on polyvinylidene fluoride‐trifluoroethylene copolymer and hydrophobized clay 下载免费PDF全文
Sara Dalle Vacche Fabiane Oliveira Olha Sereda Antonia Neels Alex Dommann Dragan Damjanovic Yves Leterrier 《Journal of Polymer Science.Polymer Physics》2017,55(24):1828-1836
Nanocomposites based on polyvinylidene fluoride–trifluoroethylene copolymer and up to 4 vol % of hydrophobized clay nanoparticles are investigated. The structure, piezoelectric properties, and oxygen permeability of solvent cast films are analyzed before and after annealing above the Curie temperature of the polymer. Exfoliation of the clay takes place at concentrations up to 1 vol %, beyond which it rapidly drops and is absent at a concentration of 4 vol %. The presence of clay does not change the crystallinity of the polymer, but leads to a threefold decrease of the oxygen permeability at a concentration of 0.5 vol %. Annealing at 130 °C increases the crystallinity, the proportion of β phase up to 94%, and the piezoelectric coefficient by 20–40% at clay fractions below 1 vol %. Annealing also leads to a remarkable 3‐ to 10‐fold decrease of O2 permeability and to intriguing changes of the activation energy for O2 transport, which decreases from 56 kJ/mol for the as‐cast polymer to below 10 kJ/mol for the polymer and exfoliated composite. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 1828–1836 相似文献