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301.
介绍了LCD(液晶显示器)的基本工作原理和三星S3C44B0X的内置LCD控制器以及Linux操作系统下的设备管理.讨论了基于三星S3C44B0X内置LCD控制器的LCD驱动程序开发,重点介绍了将LCD驱动程序添加到Linux内核配置系统中的方法,使LCD驱动在Linux系统下得以实现. 相似文献
302.
介绍了一种与传统MTF法完全不同的测量电流密度因子n的新型动态电流斜坡测试法。测试了4种不同样品。结果表明,n值与材料有关,并符合BLACK方程。 相似文献
303.
以香草酸甲酯为原料, 经过7步反应合成了前体化合物(S)-3-[5-{(1-乙基-2-吡咯烷基)甲基胺甲基}-2,3-二甲氧基苯基]丙基-4-甲基苯磺酸酯, 采用NMR和HRMS对其进行了表征; 通过18F标记合成了新型高亲和力的多巴胺受体显像剂18F-(S)-N-{(1-乙基2-吡咯烷基)甲基}-3-(3-氟丙基)-4,5-二甲氧基苯甲酰胺(18F-Fethypride). 该显像剂的合成时间为35 min, 放化产率为(36.8±1.4)%(n=6), 放化纯度经HPLC法检测为99%, TLC法检测为100%, 无菌实验、 鲎试剂检测、 K2.2.2含量检测和急性毒性实验均合格. 纹状体/小脑(Str/Cer)比值90 min达到最高(10.68±0.35), 可作为多巴胺受体显像剂用于诊断神经系统疾病. 相似文献
304.
Yinghua Gong Pengfei Yang Furong Tao Datong Zhang Xiaofei Guo 《International Journal of Polymer Analysis and Characterization》2014,19(2):107-114
The urethane reaction of symmetrical diisocyanate 1,3-diazetidine-2,4-dione (uretdione) with 4-(tetrahydro-pyran-2-yloxy)-butan-1-ol (mono-THP ether) was carried out in chlorobenzene with 1,4-diazabicyclo [2.2.2] octane (DABCO) or dibutyltin dilaurate (DBTDL) as catalyst. Analysis of the second-order rate constants of those systems indicated that k followed the order of DABCO>DBTDL. Then the kinetics of the urethane reaction was studied by means of in situ FT-IR. Due to a greater distance apart of the two isocyanate groups in the molecule, there was no significant reactivity difference between them. Finally, activation energy, activation enthalpy, and activation entropy for the catalyzed reaction were also determined, followed by a discussion of the reaction mechanism. 相似文献
305.
Utilizing model reference adaptive control theory and Lyapunov stability theorem, we derive the adaptive law for the model reference adaptive system. Then we design the Lyapunov control law by double control functions and investigate the orbit tracking of quantum state for non-Markovian quantum system with phase relaxation and energy dissipative relaxation. The influence of Ohmic reservoir with Lorentz-Drude regularization is numerically studied for a two-level system. The simulations show that the controlled quantum system will track the target orbit with a small oscillation due to the non-Markovian environmental memory effect, which indicates the orbit tracking of non-Markovian quantum system is incomplete. 相似文献
306.
In this paper, quadratic B-spline functions are used for solution of 2-D elastic problems. Because B-spline functions are directly used as basis function, there is no need to use meshes and nodes in function approximation. In order to improve the computational efficiency, different scales are used for sub-domains of entire problem domain in function approximation. The modified variational form and Lagrange multipliers method are used for coupling of different scale in function approximation. Compared with meshless methods and other wavelet based methods, this multi-scale B-spline-based method is simple and easy to work with for numerical analysis. Furthermore, the computational efficiency of the multi-scale method is much higher than that of single scale approach. The numerical examples of 2-D elastic problems indicate that the present method is effective and stable for solving complicated problems. 相似文献
307.
Yb3 dopedsolidstatematerialsareattractiveasgainmediaofhighefficiencyandhighpowerwiththedevelopmentofInGaAslaserdiode.Amongthen?.. 相似文献
308.
309.
In this paper,using the Krasnaselskii's fixed point theory in cones and localization method,under more general conditions,the existence of n positive solutions to a class of fourth-order singular boundary value problems is considered. 相似文献
310.
Effect of realgar on extracellular amino acid neurotransmitters in hippocampal CA1 region determined by online microdialysis–dansyl chloride derivatization–high‐performance liquid chromatography and fluorescence detection
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Taoguang Huo Yinghua Zhang Weikai Li Huilei Yang Hong Jiang Guifan Sun 《Biomedical chromatography : BMC》2014,28(9):1254-1262
An online microdialysis (MD)–dansyl chloride (Dns) derivatization–high‐performance liquid chromatography (HPLC) and fluorescence detection (FD) system was developed for simultaneous determination of eight extracellular amino acid neurotransmitters in hippocampus. The MD probe was implanted in hippocampal CA1 region. Dialysate and Dns were online mixed and derivatized. The derivatives were separated on an ODS column and detected by FD. The developed online system showed good linearity, precision, accuracy and recovery. This online MD‐HPLC system was applied to monitor amino acid neurotransmitters levels in rats exposed to realgar (0.3, 0.9 and 2.7 g/kg body weight). The result shows that glutamate concentrations were significantly increased (p < 0.05) in hippocampal CA1 region of rats exposed to three doses of realgar. A decrease in γ‐aminobutyric acid concentrations was found in rats exposed to medium and high doses of realgar (p < 0.05). Elevation of excitotoxic index (EI) values in hippocampal CA1 region of realgar‐exposed rats was observed (p < 0.05). Positive correlation was found between EI values and arsenic contents in hippocampus of realgar‐exposed rats, which indicates that the change in extracellular EI values is associated with arsenic accumulation in hippocampus. The developed online MD–Dns derivatization–HPLC–FD system provides a new experimental method for studying the effect of toxic Chinese medicines on amino acid neurotransmitters. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献