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141.
Structural Chemistry - Three new versatile azido-bridged Schiff base Copper(II) complexes, [Cu2(L1)2(μ1,1-N3)2]·2CH3OH (1), [Cu(L2)(μ1,3-N3)] n (2), and [Cu2(L3)(μ1,1-N3)2(N3)]2... 相似文献
142.
Yong Hee Kim Nam Seob Baek Kook Hwa Kim Sang-Don Jung 《Journal of Sol-Gel Science and Technology》2012,64(2):304-308
We present herein a simple protocol of growing a patterned ZnO nanowire by etching of ZnO seed layer in the tetramethyl ammonium hydroxide (TMAH) solution. The ZnO seed layer was fabricated by sol–gel method using zinc acetate solution and patterned by using photolithographic method. Patterned ZnO seed layer as etched in the TMAH solution, followed by growth of ZnO nanowires by hydrothermal method. Remarkable point of present ZnO seed layer patterning is that development of UV-exposed photoresist and etching of ZnO seed layer is subsequently processed in aqueous TMAH solution without interruption. The grown ZnO nanowires were analyzed using XRD patterns to exhibit high purity and degree of crystallinity, and showed very good pattern fidelity. 相似文献
143.
Relationships between structure,ionization profile and sensitivity of exogenous anabolic steroids under electrospray ionization and analysis in human urine using liquid chromatography–tandem mass spectrometry
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Eunju Cha Sohee Kim Hee Won Kim Kang Mi Lee Ho Jun Kim Oh‐Seung Kwon Jaeick Lee 《Biomedical chromatography : BMC》2016,30(4):555-565
The relationships between the ionization profile, sensitivity, and structures of 64 exogenous anabolic steroids (groups I–IV) was investigated under electrospray ionization (ESI) conditions. The target analytes were ionized as [M + H]+ or [M + H–nH2O]+ in the positive mode, and these ions were used as precursor ions for selected reaction monitoring analysis. The collision energy and Q3 ions were optimized based on the sensitivity and selectivity. The limits of detection (LODs) were 0.05–20 ng/mL for the 64 steroids. The LODs for 38 compounds, 14 compounds and 12 compounds were in the range of 0.05–1, 2–5 and 10–20 ng/mL, respectively. Steroids including the conjugated keto‐functional group at C3 showed good proton affinity and stability, and generated the [M + H]+ ion as the most abundant precursor ion. In addition, the LODs of steroids using the [M + H]+ ion as the precursor ion were mostly distributed at low concentrations. In contrast, steroids containing conjugated/unconjugated hydroxyl functional groups at C3 generated [M + H ? H2O]+ or [M + H ? 2H2O]+ ions, and these steroids showed relatively high LODs owing to poor stability and multiple ion formation. An LC‐MS/MS method based on the present ionization profile was developed and validated for the determination of 78 steroids (groups I–V) in human urine. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Microchimica Acta - A sensitive fluorometric assay is reported for label-free detection of the activity of protein kinase (PKA) and of its inhibitors. It is based on the europium(III)-modulated... 相似文献
147.
Yuhong Chen Qishuai Jiao Liang Wang Yawei Hu Na Sun Yushuang Shen Yuhua Wang 《Comptes Rendus Chimie》2013,16(9):845-849
In order to improve the thermal stability and dynamic performance of LiCo1/3Ni1/3Mn1/3O2 materials, Cl-doped and Br-doped materials were synthesized via the co-precipitation method. The morphology, structure, electrochemical performance and thermal stability were characterized by environment scanning electron microscopy (ESEM), X-ray diffraction (XRD), electrochemical impedance spectroscopy (EIS), charge–discharge cycling and differential scanning calorimetry (DSC). Results show that all materials had a stable layered structure with α-NaFeO2 and that Cl-doping slightly increased the size of grains. Both Cl-doping and Br-doping improved the high rate of discharge capacity, cycle-life performance and thermal stability, but Cl-doping was better than Br-doping in improving the material structure stability, dynamic performance and thermal stability. 相似文献
148.
In Situ Proteome Profiling and Bioimaging Applications of Small‐Molecule Affinity‐Based Probes Derived From DOT1L Inhibitors
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Biwei Zhu Dr. Hailong Zhang Sijun Pan Chenyu Wang Dr. Jingyan Ge Prof. Dr. Jun‐Seok Lee Prof. Dr. Shao Q. Yao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(23):7824-7836
DOT1L is the sole protein methyltransferase that methylates histone H3 on lysine 79 (H3K79), and is a promising drug target against cancers. Small‐molecule inhibitors of DOT1L such as FED1 are potential anti‐cancer agents and useful tools to investigate the biological roles of DOT1L in human diseases. FED1 showed excellent in vitro inhibitory activity against DOT1L, but its cellular effect was relatively poor. In this study, we designed and synthesized photo‐reactive and “clickable” affinity‐based probes (AfBPs), P1 and P2 , which were cell‐permeable and structural mimics of FED1 . The binding and inhibitory effects of these two probes against DOT1L protein were extensively investigated in vitro and in live mammalian cells (in situ). The cellular uptake and sub‐cellular localization properties of the probes were subsequently studied in live‐cell imaging experiments, and our results revealed that, whereas both P1 and P2 readily entered mammalian cells, most of them were not able to reach the cell nucleus where functional DOT1L resides. This offers a plausible explanation for the poor cellular activity of FED1 . Finally with P1 / P2 , large‐scale cell‐based proteome profiling, followed by quantitative LC‐MS/MS, was carried out to identify potential cellular off‐targets of FED1 . Amongst the more than 100 candidate off‐targets identified, NOP2 (a putative ribosomal RNA methyltransferase) was further confirmed to be likely a genuine off‐target of FED1 by preliminary validation experiments including pull‐down/Western blotting (PD/WB) and cellular thermal shift assay (CETSA). 相似文献
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This paper investigates the nonlinear control problem for flexible air-breathing hypersonic vehicles (FAHVs). The coupling dynamics between flexible and rigid-body parts of FAHVs may cause degradation of control performance or high-frequency oscillations of control input and flexible state. In this paper, the flexible effects produced by the coupling are modeled as a kind of unknown disturbance and included in the new control-design model, for which a coupling observer is constructed to estimate these effects. Thus, a novel nonlinear composite control strategy, which combines a coupling-observer-based feedforward compensator and a dynamic-inversion-based feedback controller, is proposed to reject the flexible effects on pitch rate and track desired trajectories of velocity and flight-path angle. The stability of composite closed-loop system is analyzed by using the Lyapunov theory. Simulation results on a full nonlinear model of FAHVs demonstrate that the presented controller is more effective by comparison with the previous scheme. 相似文献