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排序方式: 共有127条查询结果,搜索用时 31 毫秒
1.
We report a self‐propelled Janus silica micromotor as a motion‐based analytical method for achieving fast target separation of polyelectrolyte microcapsules, enriching different charged organics with low molecular weights in water. The self‐propelled Janus silica micromotor catalytically decomposes a hydrogen peroxide fuel and moves along the direction of the catalyst face at a speed of 126.3 μm s?1. Biotin‐functionalized Janus micromotors can specifically capture and rapidly transport streptavidin‐modified polyelectrolyte multilayer capsules, which could effectively enrich and separate different charged organics in water. The interior of the polyelectrolyte multilayer microcapsules were filled with a strong charged polyelectrolyte, and thus a Donnan equilibrium is favorable between the inner solution within the capsules and the bulk solution to entrap oppositely charged organics in water. The integration of these self‐propelled Janus silica micromotors and polyelectrolyte multilayer capsules into a lab‐on‐chip device that enables the separation and analysis of charged organics could be attractive for a diverse range of applications. 相似文献
2.
We construct a nonauto Darboux transformation for the extended noncommutative Kadomtsev–Petviashvili (ncKP) hierarchy and consequently derive its quasi-Wronskian solution. We also obtain the quasi-Wronskian solution of the ncKP equation with self-consistent sources (ncKPESCS) as a by-product. Finally, we use the direct verification method to prove the quasi-Wronskian solution of the ncKPESCS. 相似文献
3.
Scaling usually causes serious problems in daily life and industrial production. Currently, developing passive anti-scaling coatings has shown promises to overcome this problem. In this work, we fabricated a scalable and robust bio-inspired organogel(BIO) coating, showing dynamic scale resistance in the oil/brine mixture. The oil layer of the BIO coating was utilized as a barrier to inhibit scale nucleation and reduce scale adhesion. The mechanical strength of the coating was optimized by regulating nanoparticle contents. Moreover, the universality of scale resistance was demonstrated by varying the types of nanoparticles, oils and scales. Compared with commercial pipeline materials, such as copper, this BIO coating significantly reduces scale deposition after 240-h scaling test(ca. 93% reduction). Therefore, this study designs scalable and robust organogel coatings for sustainable scale resistance, which may be used for practical application in oil production. 相似文献
4.
基于相平均方法的折射绕射联合波浪模型 总被引:1,自引:0,他引:1
近岸带波浪运动的研究具有很重要的工程意义,近年来已获得了较丰硕的研
究成果并发展了许多波浪模型,而基于不同理论的波浪模型往往具有特定的适用性. 在海岸
工程中应用比较广泛的一类波浪模型以波能(波作用量)守恒为基本依据,如SWAN模型. 该
类模型在实际工程中已经得到了大量的应用,但该类模型未计及波浪绕射效应,成为其突出
的缺陷之一. 如何对模型做适当的改进,使之适用于波浪绕射的模拟,从而在原有基础上拓
广模型的应用范围是一项具有实际意义的研究工作. 该文采用波能(波作用量)守恒方程描
述近岸带波浪运动,通过引入绕射因子,得到折射、绕射联合波浪模型,从而拓广了模型的
应用范围. 通过实际算例验证,表明所建立的模型计及了波浪折射、绕射作用,对相平
均波浪模型在波浪绕射效应模拟方面的改进具有一定的意义. 相似文献
5.
6.
Self‐Propelled Janus Mesoporous Silica Nanomotors with Sub‐100 nm Diameters for Drug Encapsulation and Delivery 下载免费PDF全文
Mingjun Xuan Jingxin Shao Dr. Xiankun Lin Dr. Luru Dai Prof. Qiang He 《Chemphyschem》2014,15(11):2255-2260
The synthesis of an innovative self‐propelled Janus nanomotor with a diameter of about 75 nm that can be used as a drug carrier is described. The Janus nanomotor is based on mesoporous silica nanoparticles (MSNs) with chromium/platinum metallic caps and propelled by decomposing hydrogen peroxide to generate oxygen as a driving force with speeds up to 20.2 μm s?1 (about 267 body lengths per second). The diffusion coefficient (D) of nanomotors with different H2O2 concentrations is calculated by tracking the movement of individual particles recorded by means of a self‐assembled fluorescence microscope and is significantly larger than free Brownian motion. The traction of a single Janus MSN nanomotor is estimated to be about 13.47×10?15 N. Finally, intracellular localization and drug release in vitro shows that the amount of Janus MSN nanomotors entering the cells is more than MSNs with same culture time and particle concentrations, meanwhile anticancer drug doxorubicin hydrochloride loaded in Janus MSNs can be slowly released by biodegradation of lipid bilayers in cells. 相似文献
7.
Jingxin Mo Paul K. Eggers Colin L. Raston Lee Yong Lim 《Analytical and bioanalytical chemistry》2014,406(11):2659-2667
Carboplatin and paclitaxel co-loaded nanovesicles (CPT-PTX-CLV), a novel intravenous formulation void of cremophor EL, may have significant advantages over conventional carboplatin and paclitaxel formulations with respect to tumor targeting, sustained drug release, reduced toxicity, and synergistic efficacy profiles. The aim of this study was to develop and validate a rapid, specific, sensitive, and reliable liquid chromatography–time of flight–mass spectrometry (LC/TOF MS)-based bioanalytical method for the simultaneous quantification of CPT and PTX in a fetal bovine serum (FBS) vehicle containing the dispersed nanovesicles. The analytes were extracted from FBS by simple protein precipitation, with subsequent separation of CPT and PTX on a Waters HPLC SunFire C18 column at a flow rate of 0.25 ml/min using gradient elution mode. The total analytical time was only 12 min. Detection and quantitation was performed by electrospray ionization (ESI) in the positive ionization mode with selective ion monitoring (SIM) at m/z 310.0152 for CPT and 876.3224 for PTX. The calibration curves were linear over the concentration range of 10–4,000 ng/ml for CPT and 5–2,000 ng/ml for PTX (r 2 ?>?0.99), with the respective lower limit of quantification (LLOQ) at 10 and 5 ng/ml. The intra- and inter-day precision and accuracy of analysis of the quality control samples at low, medium, and high concentration levels were ≤13.6 % relative standard deviation (RSD) and ≤14.6 % relative errors (RE). The rapid, sensitive, and reproducible LC/TOF MS method may be used to support preclinical and clinical pharmacological studies of the CPT-PTX-CLV administered by injection in animal and human cancer models. Figure
Typical SIM chromatograms for the LLOQ samples: carboplatin (upper) at m/z 310.0152 and paclitaxel (lower) at m/z 876.3224. 相似文献
8.
Jiang Liang Lei Yuan Liu Qinfeng Wang Yi Zhao Yuanyang Lei Jingxin 《Journal of Thermal Analysis and Calorimetry》2020,139(1):137-146
Journal of Thermal Analysis and Calorimetry - The polyethylene glycol/wood-flour (PEG/WF) composites were synthesized as novel form-stable phase change materials (PCMs) using PEG as phase change... 相似文献
9.
Liu Zhimeng Jiang Liang Fu Xiaowei Zhang Junhua Lei Jingxin 《Journal of Thermal Analysis and Calorimetry》2020,140(5):2159-2170
Journal of Thermal Analysis and Calorimetry - In this study, a series of gelators (Gn, n is the number of carbon atoms of used fatty alcohol, n?=?2, 4, 6, 8, 10, 12, 14, 16 and 18) were... 相似文献
10.
Zhang Yanli Zhang Qiang Wang Jingxin Sheng Li Wang Li Xie Yingpeng Hao Yongsheng Dong Liangliang He Xiangming 《Journal of Solid State Electrochemistry》2022,26(12):2601-2626
Journal of Solid State Electrochemistry - Iron(II) fluoride (FeF2) is a promising candidate as the cathode material for lithium-ion batteries (LIBs) due to its quite high theoretical energy density... 相似文献