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141.
The design and preliminary charaterization of a novel fiber optic-based fluorimeter are reported. It includes a white light source, optical fibers for light transmission and an intensified photodiode array for detection. A bifurcated sensing configuration is used to transmit excitation and emission radiation to and from the analyte solution. Detection limits in the nanomolar range are reported for several test compounds. 相似文献
142.
A series of pentacarbonyl complexes of chromium and molybdenum with unicoordinated-diphosphines, M(CO)5(η1-P-P) (P-P = dppe, dppp, dppb) has been prepared by amine oxide-induced phosphine substitution of the binary carbonyls. The basicity of the pendant phosphine groups was demonstrated by their ready conversion to the diphosphine-bridged heterobimetallic complexes (OC)5M(μ-P-P)M′(CO)5 (M, M′= Cr, Mo, W; M ≠ M′) in the presence of MCO)5(CH3CN). The complexes were characterized by IR and NMR (1H and 31P-{1H}) spectroscopy. 相似文献
143.
Prof. Dr. Ying Zhang Der-Shyang Kao Dr. Bing Gu Dr. Rajdeep Bomjan Dr. Mayank Srivastava Prof. Dr. Haojie Lu Prof. Dr. Daoguo Zhou Prof. Dr. W. Andy Tao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(6):2255-2260
Studying the dynamic interaction between host cells and pathogen is vital but remains technically challenging. We describe herein a time-resolved chemical proteomics strategy enabling host and pathogen temporal interaction profiling (HAPTIP) for tracking the entry of a pathogen into the host cell. A novel multifunctional chemical proteomics probe was introduced to label living bacteria followed by in vivo crosslinking of bacteria proteins to their interacting host-cell proteins at different time points initiated by UV for label-free quantitative proteomics analysis. We observed over 400 specific interacting proteins crosslinked with the probe during the formation of Salmonella-containing vacuole (SCV). This novel chemical proteomics approach provides a temporal interaction profile of host and pathogen in high throughput and would facilitate better understanding of the infection process at the molecular level. 相似文献
144.
Andy Shun-Hoi CHEUNG Sammual Yu-Lut LEUNG Franky Ka-Wah HAU Vivian Wing-Wah YAM 《高等学校化学研究》2021,37(5):1079-1084
Alkynylplatinum(II) bzimpy complexes of trimethylammonium-benzylethynyl ligand have been synthesized and characterized. Complexes with long alkyl chains have been found to exhibit interesting self-assembly properties in the acetonitrile solution. The amphiphilic nature of the complexes has led to the formation of nanorods, as revealed by electron microscopy experiments. Further increasing the polarity of the solvent media has given rise to the enhancement of low-energy emission. 相似文献
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148.
Patrick Fadden Kenneth H. Huang James M. Veal Paul M. Steed Amy F. Barabasz Briana Foley Mei Hu Jeffrey M. Partridge John Rice Anisa Scott Laura G. Dubois Tiffany A. Freed Melanie A. Rehder Silinski Thomas E. Barta Philip F. Hughes Andy Ommen Wei Ma Emilie D. Smith Angela Woodward Spangenberg Jeron Eaves Steven E. Hall 《Chemistry & biology》2010,17(7):686-694
149.
Meng-Yu Tsai Yvonne Wu Leia Fan Elaine Jian Jason Lin Jessica Tseng Andy Tseng Renee Wan Eric Lee 《Electrophoresis》2022,43(3):495-500
A simple analytical formula is obtained for the diffusiophoresis of a dielectric fluid droplet in symmetric binary electrolyte solutions under Debye–Hückel approximation valid for weakly charged droplets. The chemiphoresis is found to yield negative mobilities most of the time for droplets of constant surface charge density, which implies that the droplets tend to move away from the source releasing ionic chemicals. This is undesirable in some practical applications like drug delivery with liposomes in terms of conveying the drug-carrying liposomes to the desired area in the human body releasing specific ionic chemicals utilizing the self-guiding nature of diffusiophoresis. The further involvement of the electrophoresis component, however, may change the scenario via the oriented electric field generated by the induced diffusion potential. The lesson here is that while the impact of the chemiphoresis component is determined by nature and uncontrollable, the electrophoresis component serves as an artificially adjustable factor via choosing droplets with the surface charge of appropriate sign in practical applications. The results here have potential use in practical applications such as drug delivery. The portable simple analytical formula is a powerful asset to experimental researchers and design engineers in colloid science and technology to facilitate their works. 相似文献
150.
Let Π = B_1/B_2/… /B_k be any set partition of[n]= {1,2,...,n} satisfying that entries are increasing in each block and blocks are arranged in increasing order of their first entries.Then Callan defined the flattened Π to be the permutation of[n]obtained by erasing the divers between its blocks,and Callan also enumerated the number of set partitions of[n]whose flattening avoids a single3-letter pattern.Mansour posed the question of counting set partitions of[n]whose flattening avoids a pattern of length 4.In this paper,we present the number of set partitions of[n]whose flattening avoids one of the patterns:1234,1243,1324,1342,1423,1432,3142 and 4132. 相似文献