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排序方式: 共有432条查询结果,搜索用时 15 毫秒
1.
Nguyen H. N. Vu M. A. Hy D. M. Ta N. A. Do A. T. 《Journal of Applied and Industrial Mathematics》2021,15(2):315-325
Journal of Applied and Industrial Mathematics - In this paper, we introduce a nonlinear Lanchester-type model involving supply units. The model describes a battle where the Blue party consisting of... 相似文献
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Yutong Pi Linxia Cui Prof. Wenhao Luo Dr. Haitao Li Dr. Yanfu Ma Dr. Na Ta Xinyao Wang Prof. Rui Gao Prof. Dan Wang Prof. Qihua Yang Prof. Jian Liu 《Angewandte Chemie (International ed. in English)》2023,62(43):e202307096
Mimicking the structures and functions of cells to create artificial organelles has spurred the development of efficient strategies for production of hollow nanoreactors with biomimetic catalytic functions. However, such structure are challenging to fabricate and are thus rarely reported. We report the design of hollow nanoreactors with hollow multishelled structure (HoMS) and spatially loaded metal nanoparticles. Starting from a molecular-level design strategy, well-defined hollow multishelled structure phenolic resins (HoMS-PR) and carbon (HoMS-C) submicron particles were accurately constructed. HoMS-C serves as an excellent, versatile platform, owing to its tunable properties with tailored functional sites for achieving precise spatial location of metal nanoparticles, internally encapsulated (Pd@HoMS-C) or externally supported (Pd/HoMS-C). Impressively, the combination of the delicate nanoarchitecture and spatially loaded metal nanoparticles endow the pair of nanoreactors with size–shape-selective molecular recognition properties in catalytic semihydrogenation, including high activity and selectivity of Pd@HoMS-C for small aliphatic substrates and Pd/HoMS-C for large aromatic substrates. Theoretical calculations provide insight into the pair of nanoreactors with distinct behaviors due to the differences in energy barrier of substrate adsorption. This work provides guidance on the rational design and accurate construction of hollow nanoreactors with precisely located active sites and a finely modulated microenvironment by mimicking the functions of cells. 相似文献
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Capillary electrophoresis-frontal analysis is one of the most frequently used approaches for the study of plasma protein-drug interactions as a substantial part of new drug development. However, the capillary electrophoresis-frontal analysis typically combined with ultraviolet-visible detection suffers from insufficient concentration sensitivity, particularly for substances with limited solubility and low molar absorption coefficient. The sensitivity problem has been solved in this work by its combination with an on-line sample preconcentration. According to the knowledge of the authors this combination has never been used to characterize plasma protein-drug binding. It resulted in a fully automated and versatile methodology for the characterization of binding interactions. Further, the validated method minimalizes the experimental errors due to a reduction in the manipulation of samples. Moreover, employing an on-line preconcentration strategy with capillary electrophoresis-frontal analysis using human serum albumin-salicylic acid as a model system improves the drug concentration sensitivity 17-fold compared to the conventional method. The value of binding constant (1.51 ± 0.63) · 104 L/mol obtained by this new capillary electrophoresis-frontal analysis modification is in agreement with the value (1.13 ± 0.28) ·104 L/mol estimated by a conventional variant of capillary electrophoresis-frontal analysis without the preconcentration step, as well as with literature data obtained using different techniques. 相似文献
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Dan Yuan Sharda Yadav Hang T. Ta Hedieh Fallahi Hongjie An Navid Kashaninejad Chin Hong Ooi Nam-Trung Nguyen Jun Zhang 《Electrophoresis》2021,42(21-22):2230-2237
Microfluidic particle focusing has been a vital prerequisite step in sample preparation for downstream particle separation, counting, detection, or analysis, and has attracted broad applications in biomedical and chemical areas. Besides all the active and passive focusing methods in Newtonian fluids, particle focusing in viscoelastic fluids has been attracting increasing interest because of its advantages induced by intrinsic fluid property. However, to achieve a well-defined focusing position, there is a need to extend channel lengths when focusing micrometer-sized or sub-microsized particles, which would result in the size increase of the microfluidic devices. This work investigated the sheathless viscoelastic focusing of particles and cells in a zigzag microfluidic channel. Benefit from the zigzag structure of the channel, the channel length and the footprint of the device can be reduced without sacrificing the focusing performance. In this work, the viscoelastic focusing, including the focusing of 10 μm polystyrene particles, 5 μm polystyrene particles, 5 μm magnetic particles, white blood cells (WBCs), red blood cells (RBCs), and cancer cells, were all demonstrated. Moreover, magnetophoretic separation of magnetic and nonmagnetic particles after viscoelastic pre-focusing was shown. This focusing technique has the potential to be used in a range of biomedical applications. 相似文献
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Control of the flow around a circular cylinder is studied using Large Eddy Simulation. The influence of control by rotation and suction on the flow characteristics is considered for several Reynolds numbers. Comparisons with experiments were conducted at for the flow with and without control. A drag reduction up to 30% is obtained for an usual suction intensity. To cite this article: G. Fournier et al., C. R. Mecanique 333 (2005). 相似文献
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The ac conductivity of three fluorides of A2MII+ MIII + F9 type, Sr2NiAlF9, Sr2ZnGaF9 and Ba2MnCrF9, between 293 and 773K, has been analyzed within a combined complex impedance and modulus formalism. The antiferroelectric-paraelectric phase transition of Sr2ZnGaF9 has been characterized. A hopping mechanism for charge carriers is suggested for the three materials; their electrical performance are relatively weak. Sr2NiAlF9 and Sr2ZnGaF9 can be considered as ionic conductors of the F- ion. On the contrary, the conductivity in Ba2MnCrF9 is rather of an electronic nature. 相似文献
9.
Betül Taşdelen 《Journal of Radioanalytical and Nuclear Chemistry》2011,290(2):283-287
Technetium-99m-sestamibi (99mTc-MIBI) is a small, lipophilic and cationic compound used for myocardial perfusion imaging. In addition, 99mTc-MIBI has been shown to be useful in identifying several types of tumors, such as breast, lung and thyroid cancers. The
high quality of this radiopharmaceutical and its uniformity are very important facts for application of this preparation in
clinical practice. The monograph for 99mTc-MIBI recommends at least 90% radiochemical purity (RCP) for clinical use. Various factors may influence the RCP of certain
reagent kits. Some of these include the amount of activity added to the reagent kit, heating time and the age of the formulated
kit. The effect of these factors on RCP of 99mTc-MIBI has been investigated using high performance liquid chromatography (HPLC) and instant thin layer chromatography. 相似文献
10.
Betül Taşdelen Aysun Ergun Fikret Büyükkaya 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(2):573-575
DOTA-conjugated peptides, such as [DOTA0, Tyr3]ocreotide (DOTATOC) and [DOTA0, Tyr3]octreotate (DOTATATE) can be labeled with radionuclides such as 90Y, 177Lu and 111In at high specific activities. These radiolabelled somatostatin analogues are used for peptide receptor radionuclide therapy
(PRRT). Currently, radio-high performance liquid chromatography (radio-HPLC) and radio-thin layer chromatography (radio-TLC)
are the methods of choice for the analysis of the labeled compounds. In literature, radiochemical purity of the radiolabelled
DOTATATE was investigated using gradient reversed-phase radio-HPLC. However, these studies indicate long retention time of
the radiolabelled compound of 14.52 min. In our study, a new simple and rapid reversed-phase isocratic system enables the
radiochemical purity of the radiolabelled DOTATATE within a few minutes. 相似文献