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991.
为实现对循环水水质的远程监测,设计并开发了一种基于嵌入式技术的热力站远程水质监测系统的监测终端。监测终端由水质传感器、GPRS模块、通信转换模块及嵌入式开发板组成。嵌入式开发板以ARM11系列的Tiny6410为硬件基础,并嵌入WinCE系统作为软件平台,同时加入SQLite数据库以实现将水质传感器采集到的氯离子、PH值、溶解氧等参数的本地存储、查询及图表显示。最后监测终端通过GPRS模块与数据中心建立无线连接,接收数据中心的配置命令,并将现场测得数据发送到远端数据中心。调试结果表明:远程监测终端实现了循环水水质远程监测的功能要求,对于实现水质自动化监测具有一定的理论意义和实用价值。 相似文献
992.
单重态氧O2 (a1Δg)是迄今唯一能用纯化学反应高效产生的具有长寿命的亚稳激发态分子 .为了考察提出的用两个O2 (1Δ)能量汇集反应生成氧第二单重激发态O2 (b1Σ+ g)以实现近可见短波长化学激光方案的现实性 ,设计和实验了一个氯流量为 3~ 10mmol/s的射流式单重态氧发生器 (JSOG) .考察了三种具有不同孔径和孔数目的喷头、氯气流量和脱水冷阱温度等对JSOG出口的O2 (1Δ)浓度、O2 (1Δ)分压、氯利用率及水蒸气含量的影响 .发现用聚氯乙烯管作冷阱时 ,最佳冷阱介质温度为 - 140~ - 15 0℃ ,对此提出了O2 (1Δ)表面脱活与脱水互相竞争的解释 .在最佳条件下 ,可将O2 (1Δ)气中水分压降低至 4Pa ,这一结果是首次报导 相似文献
993.
WuBing Yang FengGan Zhuang Qing Shen FaMing Guan Qiang Wang ShiHe Yi YuXin Zhao Lin He LiFeng Tian 《中国科学G辑(英文版)》2009,52(10):1624-1631
The parameters of instability wave of supersonic mixing layer(Mc=0.5,M1=3.5/M2=1.4) are measured by flow visualization and calculated by means of two-dimensional direct numerical simulaitons of the compressible Navier-Stokes equations.In both cases of the mixing layer with harmonic disturbance or not,the comparative results indicate that the wavelength of the two-dimensional wave is equal to the vortex spacing in the streamwise direction because the difference between them is less than 1%.However,the measur... 相似文献
994.
研究了GaN/AlGaN异质结构中的双带(中、远)红外探测及光子频率上转换特性.通过光致发光光谱确认GaN/AlGaN探测器结构中AlGaN本征层的Al组分,讨论了不同Al组分GaN/AlGaN异质结的导带带阶界面功函数差.在拟合单周期GaN/AlGaN探测器中红外和远红外波段响应谱的基础上,研究多周期GaN/AlGaN探测器与GaN/AlGaN发光二极管集成结构的中红外和远红外光子频率上转换效率与GaN发射层厚度、AlGaN本征层厚度、紫光光子出射效率、内量子效率、空间频率和发射层掺杂浓度间的关系,优化
关键词:
双带红外探测
光子频率上转换
响应谱
GaN/AlGaN 相似文献
995.
The nuclear shapes of 187,189Tl were investigated theoretically in this work. The total routhian surface (TRS) calculations were performed for N=106 and 108 isotopes of thallium (Z=81). The single-particle energies were obtained from the deformed Woods-Saxon potential, with the Lipkin-Nogami (LN) treatment
of pairing. It is found that the collective oblate rotation coexists with the high-K prolate rotation. Superdeformed prolate rotation is included in this calculation.
Supported by the National Natural Science Foundation of China (Grant Nos. 10575036 and 10675046) and the Natural Science Foundation
of Zhejiang Province of China (Grant Nos. Y605476 and Y604027) 相似文献
996.
N. G. C. Astrath F. B. G. Astrath J. Shen J. Zhou C. E. Gu L. C. Malacarne P. R. B. Pedreira A. C. Bento M. L. Baesso 《Applied physics. B, Lasers and optics》2009,94(3):473-481
A complete theoretical model is presented for the thermal mirror technique under top-hat laser excitation. Considering the
attenuation of the top-hat excitation laser intensity along the thickness of a sample due to its optical absorption coefficient,
we calculate the laser-induced temperature and surface deformation profiles. A simplified theoretical model for a high absorption
sample is also developed. The center intensity of a probe beam reflected from the thermal mirror at a detector plane is derived.
Numerical simulation shows that the thermal mirror under the top-hat laser excitation is as sensitive as that under Gaussian
laser excitation. With top-hat laser excitation, the experimental results of thermo-physical properties of opaque samples
are found to be well consistent with literature values, validating the theory. 相似文献
997.
Dongliang Zhu Jie Huang Hui Li Mingrong Shen Xiaodong Su 《Physica C: Superconductivity and its Applications》2009,469(22):1977-1982
YBa2Cu3O7–δ (YBCO) films were prepared on (1 0 0) MgO substrates by pulsed laser deposition (PLD) method. In order to eliminate the a-axis growth, which is commonly observed in the YBCO film thicker than a critical value, we developed a new PLD target that was sintered at a temperature far below YBCO 123 phase formation. The surface analysis made by AFM technique confirmed that very fine particles of around 20 nm size could be ejected from the new target to the substrate. The fine oxide clusters could be easily moved and incorporated into the YBCO phase thus benefited the c-axis growth even in the thick films. For instance, only the c-axis growth in the new film with a thickness of about 650 nm was larger than a critical thickness of the a-axis growth. However, in the standard film of the same thickness, there is 24.5% of the a-axis growth accompanying the main c-axis growth. Therefore, the c-axis growth could be preserved in the very thick YBCO film by a non-superconducting target. 相似文献
998.
研究一类具有连续变量的二阶中立型时滞差分方程△r^2[x(t)-cx(t-τ)=p(t)x(t-σ)的解的振动性,给出了其有界振动的几个充分条件. 相似文献
999.
Hai Wang Yong Liu Hong Huang Minyi Zhong Hui Shen Yuanhao Wang Hongxing Yang 《Applied Surface Science》2009,255(22):9020-9025
Low resistance dye-sensitized solar cells (DSSCs) based on all-titanium substrates were proposed in this paper. To minimize the internal resistance of DSSCs, the titanium wires and titanium sheets were used as the substrates of the photoanode and the counter electrode, respectively. Compared with the FTO substrate, titanium wires could absorb much diffused light by back reflection since the reflectivity in the titanium sheet was highly increased up to 53.12%. Furthermore, the transmittance of the front cover was increased by 13.2% using the super white glass instead of FTO substrate. The thickness of TiO2 thin film coated on titanium wire was optimized to achieve a high cell performance. The efficiency of 5.6% for the cell was obtained with a Jsc of 15.41 mA cm−2, Voc of 0.59 V, and FF of 0.62. The results showed that the titanium-based DSSCs had superiority for producing the large-scale DSSCs without metal grid line. 相似文献
1000.