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排序方式: 共有870条查询结果,搜索用时 109 毫秒
1.
Teslime Erşan Didem Giray Dilgin Elif Kumrulu Umur Kumrulu Yusuf Dilgin 《Electroanalysis》2023,35(4):e202200295
This work describes the sensitive voltammetric determination of favipiravir (FAV) based on its reduction for the first time with a low-cost and disposable pencil graphite electrode (PGE). In addition, the determination of FAV was also performed based on its oxidation. Differential pulse (DP) voltammograms recorded in 0.5 M H2SO4 for the reduction of FAV show that peak currents increase linearly in the range of 1.0 to 600.0 μM with a limit of detection of 0.35 μM. The acceptable recovery values (98.9–106.0 %) obtained from a pharmaceutical tablet, real human urine, and artificial blood serum samples spiked with FAV confirm the high accuracy of the proposed method. 相似文献
2.
Liver regeneration has been studied for decades; however, its regulation remains unclear. In this study, we report a dynamic tracing of protein synthesis in rat regenerating liver with a new proteomic technique, 35S in vivo labeling analysis for dynamic proteomics (SiLAD). Conventional proteomic techniques typically measure protein alteration in accumulated amounts. The SiLAD technique specifically detects protein synthesis velocity instead of accumulated amounts of protein through 35S pulse labeling of newly synthesized proteins, providing a direct way for analyzing protein synthesis variations. Consequently, protein synthesis within short as 30 min was visualized and protein regulations in the first 8 h of regenerating liver were dynamically traced. Further, the 3.5–5 h post partial hepatectomy (PHx) was shown to be an important regulatory turning point by acute regulation of many proteins in the initiation of liver regeneration. 相似文献
3.
The use of liquid fuels such as kerosene is of interest for the Pulse Detonation Engine (PDE). In this context, a representative
gaseous mixture of the lighter products resulting from the decomposition of a kerosene of type JP-10 was studied. The detonability
limits of simple components (hydrogen, ethylene, propylene) and mixtures of these components were tested in a 50 mm diameter
and 2.5 m long detonation tube. This dimension is compatible with the applications of the aircraft industry and more particularly
the PDE. The influences of the nitrogen dilution, geometry of the DDT device (Schelkin spiral), ignition energy and initial
pressure were investigated.
This paper was based on work that was presented at the 19th International Colloquium on the Dynamics of Explosions and Reactive
Systems, Hakone, Japan, July 27 - August 1, 2003.
Communicated by J.E. Shepherd 相似文献
4.
5.
Pulse diagnosis is an important part of Chinese medicine and has played an important role in the development of Chinese medical science. However, the pulse is traditionally determined by cutting it off, which leads to a lack of objective standard pulse identification methods and affects their accuracy and feasibility. This research has studied and discussed the processing and identification of four kinds of pulse: normal pulse, wiry pulse, smooth pulse, and thready pulse. Four frequency-domain characteristics of the pulse wave and six kinds of wavelet scale energy characteristic information were extracted, and a three-layer BP (backprocessing) neural network was established. The LM (Levenberg–Marquard) algorithm and a genetic algorithm were used to improve the BP neural network, to train on and predict experimental samples, and to obtain classification accuracies of 90% and 95% respectively. Moreover, improved BP neural network based on a genetic algorithm has shown highly superior performance in terms of convergence speed and low error rate. 相似文献
6.
7.
A diode laser-pumped acoustic-optic Q-switched Nd:YAG master-oscillator power amplifier laser is presented. The laser is quasi continuously pumped at 1.1 kHz with a pulse width of 172 μs, and the ultrasonic frequency of the AO Q-switcher is set at a higher value (53 kHz). The master oscillator is designed as a thermally near-unstable-resonator, which presents an average output power of 48 W with a beam quality value of M2 = 1.41 and a Q-switching pulse duration of 121 ns. The maximum average power of the MOPA system is 654 W, and the beam quality is M2 = 6. 相似文献
8.
A. Ul-Hamid H. DafallaA. Quddus H. SaricimenL.M. Al-Hadhrami 《Applied Surface Science》2011,257(22):9251-9259
The surface of carbon steel was modified by electrochemical deposition of Ni in a standard Watt's bath using dc and pulse plating electrodeposition. The aim was to compare the microstructure and surface mechanical properties of the deposit obtained by both techniques. Materials characterization was conducted using field emission scanning electron microscope fitted with scanning transmission electron detector, atomic force microscope and X-ray diffractometer. Nanoindentation hardness, elastic modulus, adhesion, coefficients of friction and wear rates were determined for both dc and pulse electrodeposits. Experimental results indicate that pulse electrodeposition produced finer Ni grains compared to dc plating. Size of Ni grains increased with deposition. Both dc and pulse deposition resulted in grain growth in preferred (2 0 0) orientation. However, presence of Ni (1 1 1) grains increased in deposits produced by pulse deposition. Pulse plated Ni exhibited higher hardness, creep and coefficient of friction and lower modulus of elasticity compared to dc plated Ni. 相似文献
9.
Hong Wang Rui LiuWei Qiao Jiang Jun ZhuJian Zhi Feng Gui Fu DingXiaolin Zhao 《Applied Surface Science》2011,257(6):2203-2207
Adhesion performance of MEMS materials is increasingly important with the widely use of miniaturized devices. This paper proposed a novel method for improving adhesion performance between electrodeposited Ni multi-layers. The new method is to treat the Ni substrate in nickel chloride plating solution by pulse reverse current technique before electrodeposition. The dense oxide film of Ni substrate can be removed effectively by this electrochemical method, meanwhile, the proper roughness of Ni substrate is in favor of epitaxial growth during electrodeposition. Moreover, the Ni film is electrodeposited by the new method with low stress and coarse crystal grain. Consequently, the adhesion performance of Ni films is improved dramatically. The experimental results show that the adhesion performance of Ni film electrodeposited by the new method is about 3 times that of by traditional method. 相似文献
10.
Ternary polycrystalline Zn1−xCdxO semiconductor films with cadmium content x ranging from 0 to 0.23 were obtained on quartz substrate by pulse laser deposited (PLD) technique. X-ray diffraction measurement revealed that all the films were single phase of wurtzite structure grown on c-axis orientation with its c-axis lattice constant increasing as the Cd content x increasing. Atomic force microscopy observation revealed that the grain size of Zn1−xCdxO films decreases continuously as the Cd content x increases. Both photoluminescence and optical measurements showed that the band gap decreases from 3.27 to 2.78 eV with increasing the Cd content x. The increase in Cd content x also leads to the broadening of the emission peak. The resistivity of Zn1−xCdxO films decreases evidently for higher values of Cd content x. The shift of PL emission to visible light as well as the decrease of resistivity makes the Zn1−xCdxO films potential candidate for optoelectronic device. 相似文献