In this paper, we study a generalized Nicholson??s Blowflies model with feedback control and multiple time-varying delays. Under proper conditions, we employ a novel proof to establish some criteria to guarantee the global exponential convergence and permanence of this model. Moreover, we give two examples to illustrate our main results. 相似文献
The power measurement method for 3.7GHz LHCD system on HL-2A was introduced. It is found by HFSS simulation that the impact of backward wave phase on the measurement of forward power may be suppressed if the isolation of directional coupler is more than 30dB. After improving the system, the total transmission line efficiency of the LHCD system can reach 89% with maximum power 1.5MW in 2016 experiment campaign. 相似文献
Li0.98Cu0.01MnPO4/C composite cathode materials for lithium ion battery are synthesized by sol-gel method followed by heat treatment in the air. Field-emission scanning electron microscopy measurements show that both firing temperature and carbon content affect the morphology of the end products. X-ray powder diffraction analysis indicates that the samples are olivine-structured. The galvanostatic charge?Cdischarge results show that the optimal firing temperature registers 500°C and that the electrochemical performances of Li0.98Cu0.01MnPO4/C are improved by elevating its carbon amount. The cyclic ability and rate performances of LiMnPO4 are greatly improved by doping Cu. 相似文献
In this article,under suitable conditions on the internal term f(·)and the bound-ary nonlinear term g(·),we prove blow-up results for a class of nonclassical diffusion equations with nonlinear boundary condition. 相似文献
Bioanalysis assays that reliably quantify biotherapeutics and biomarkers in biological samples play pivotal roles in drug discovery and development. Liquid chromatography coupled with mass spectrometry (LC–MS), owing to its superior specificity, faster method development and multiplex capability, has evolved as one of the most important platforms for bioanalysis of biotherapeutics, particularly new scaffolds such as half-life extension platforms for proteins and peptides, as well as antibody drug conjugates. Intact LC–MS analysis is orthogonal to bottom-up surrogate peptide approach by providing whole molecule quantitation and high-level sequence and structure information. Here we review the latest development in LC–MS bioanalysis of intact proteins and peptides by summarizing recent publications and discussing the important topics such as the comparison between top-down intact analysis and bottom-up surrogate peptide approach, as well as simultaneous quantitation and catabolite identification. Key bioanalytical issues around intact protein bioanalysis such as sensitivity, data processing strategies, specificity, sample preparation and LC condition are elaborated. For peptides, topics including quantitation of intact peptide vs. digested surrogate peptide, metabolites, sensitivity, LC condition, assay performance, internal standard and sample preparation are discussed. 相似文献
C-11 (2-((7-Ethyl-3-methyl-8-(4-(2-(methyl(pyridin-2-yl)-amino)-ethoxy)phenyl)-2,6-dioxo-2,3,6,7-tetrahydro-1H-purin-1-yl)methyl)benzonitrile-one hydrochloride), which is based on the structure of rosiglitazone, was first synthesized in our laboratory and shown to be a promising anti-obesity drug candidate in our previous pharmacological study. Considering the importance of metabolic fate in vivo in the further development of drug candidates during early drug discovery, it is essential to characterize the metabolism of C-11 in vivo. In this work, a method based on ultra-high performance liquid chromatography combined with quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS) was successfully developed to investigate the in vivo metabolic profile of C-11 in rats. Rat urine, feces, and plasma samples were collected from male Sprague–Dawley rats after intravenous administration of C-11 in a single dose of 30 mg kg−1 body weight. Besides the parent drug, a total of 25 metabolites (including 18 phase I and 7 phase II metabolites) were detected and tentatively identified by comparing their mass spectrometry profiles with those of C-11. This enabled the metabolic pathways of C-11 to be proposed for the first time. Our results revealed that N-depyridinylation, N-demethylation, hydroxylation, glucuronidation, and sulfate conjugation are the predominant metabolic pathways of C-11 in rats. The present study provides systematic information on the metabolism of C-11 in vivo, which should lead to a better understanding of its safety and mechanism of action.
Four novel transitional metal complexes with 3-(4-pyridly)-4-phenyl-5-sulfhydryl- 1,2,4- triazole (HL1) and 3-(3-pyridly)-4-phenyl-5-sulfhydryl-l,2,4-triazole (HLz) were synthesized and characterized by elemental analysis, IR and X-ray diffraction. Complexes 1, 3 and 4 have two-dimensional (2-D) neutral rhombohedral grid with a (4, 4) topology. In 1, 3 and 4, all the metal ions are six-coordinated to four nitrogen atoms of four distinct ligands and two O atoms from water molecules. Complex 2 has tetranuclear CuaCI4 units which are interconnected by four desulfuri- zation ligands (L1-S) via Cu-N bonds to form a 2-D layer with (4,4) topology. 相似文献