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91.
Hao Cheng Xiujian Zhao Xiaotao Sui Yuli Xiong Jiang Zhao 《Journal of nanoparticle research》2011,13(2):555-562
CdS quantum dot (Qd)-sensitized TiO2 nanotube array photoelectrode is synthesised via a two-step method on tin-doped In2O3-coated (ITO) glass substrate. TiO2 nanotube arrays are prepared in the ethylene glycol electrolyte solution by anodizing titanium films which are deposited
on ITO glass substrate by radio frequency sputtering. Then, the CdS Qds are deposited on the nanotubes by successive ionic
layer adsorption and reaction technique. The resulting nanotube arrays are characterized by scanning electron microscopy,
X-ray diffraction (XRD) and UV–visible absorption spectroscopy. The length of the obtained nanotubes reaches 1.60 μm and their
inner diameter and wall thickness are around 90 and 20 nm, respectively. The XRD results show that the as-prepared TiO2 nanotubes array is amorphous, which are converted to anatase TiO2 after annealed at 450 °C for 2 h. The CdS Qds deposited on the TiO2 nanotubes shift the absorption edge of TiO2 from 388 to 494 nm. The results show that the CdS-sensitized TiO2 nanotubes array film can be used as the photoelectrode for solar cells. 相似文献
92.
To decrease the performance difference between the actual microscanning thermal imager and the theoretical value, a germanium lens (placed at a certain angle between the infrared focal plane array and infrared lens) dip angle model of flat optical component microscanning is introduced in this letter. The model is the basis for choosing the dip angle of the germanium lens, which is used in the microscanning thermal imager. In addition, the actual dip angle of the germanium lens is chosen according to the model, the infrared lens parameters of the thermal imager, and the germanium lens parameters of manufacture and installation. Only in this manner can the optimal performance of the microscanning thermal imager based on the flat optical component be obtained. Results of the experiments confirm the accuracy of the conclusions above. 相似文献
93.
为了实现对黄瓜病害的快速无损准确预测,基于激光诱导叶绿素荧光光谱分析技术,建立了温室黄瓜霜霉病害的预测模型.通过测定健康叶片、病菌接种3d叶片和接种6d叶片的光谱曲线,采用一阶导数光谱预处理方法,结合主成分分析数据降维方法对三组光谱数据进行特征信息提取后,建立主成分得分散点图,依据累积贡献率选取10个主成分代替导数光谱... 相似文献
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96.
The compatible carbon-silicon complex materials originated from precursor diglycerylsilane (DGS) and sugar-modified silane
N-(3-triethoxysilylpropyl)gluconamide (GLS) have gained substantial popularity by demonstrating admirable properties to stabilize
entrapped biomolecules. The microenvironment inside these materials, especially the distribution of sugar moieties inside
the matrix, which is likely the most critical factor determining compatibility of these materials, still remains unclear.
To deeply investigate the biocompatibility mechanism of these materials, we have adopted two different preparation routes
for these materials by introducing GLS into the starting DGS sol stage, but things are different after the DGS gel is formed.
A fluorescence probe rhodamine 6G is introduced herein in the DGS sol to monitor the distribution of GLS moieties, as well
as the evolution of the microenvironment inside resulting materials. All in all, the findings demonstrated that the timing
of GLS addition plays a critical role in controlling the evolution of the inner structure of materials, suggesting that this
factor provides a promising route to tune the properties of the resulting materials.
Supported by the National Natural Science Foundation of China (Grant No. 20876176), Scientific Research Foundation for the
Returned Overseas Chinese Scholars by the State Education Ministry, Key Project of Chinese Ministry of Education (Grant No.
109100), Doctoral Project of Shandong Province (Grant No. 2008BS09013), Research Foundation of Key Laboratory of Carbon Materials,
Institute of Coal Chemistry, CAS (Grant No. KFJJ0506), and Natural Science Foundation of Shandong Province (Grant No. Q2007B02) 相似文献
97.
Zhi‐Yong Guo Pan‐Pan Gai Jing Duan Jin‐Xia Zhai Sha‐Sha Zhao Sui Wang Dan‐Yi Wei 《Biomedical chromatography : BMC》2010,24(10):1094-1099
A gas chromatography–mass spectrometry assay was developed and validated for the simultaneous determination of phthalates and adipates in human serum. The phthalates and adipates studied were dimethyl phthalate, diethyl phthalate, dibutyl phthalate, benzylbutyl phthalate, di‐2‐ethylhexyl phthalate, di‐n‐octyl phthalate, diethyl adipate, dibutyl adipate, diisobutyl adipate, bis(2‐butoxyethyl) adipate and di‐2‐ethylhexyl adipate, with diisooctyl phthalate as internal standard. The extraction and cleaning up procedure was carried out with solid‐phase extraction cartridges containing dimethyl butylamine groups, which showed extraction efficiencies over 88% for each analyte and the internal standard. The calibration curves obtained were linear with correlation coefficients greater than 0.98. For all analytes, the assay gave CV% values for intra‐day precision from 4.9 to 13.3% and mean accuracy values from 91.4 to 108.4%, while inter‐day precision was 5.2–13.4% and mean accuracy 91.0–110.2%. The limits of detection for the assay of phthalates and adipates were in the range 0.7–4.5 ng/mL. The method is simple, sensitive and accurate, and allows for simultaneous determination of nanogram levels of phthalates and adipates in human serum. It was successfully applied to an investigation on the level of phthalates and adipates in a non‐occupationally exposed population. 相似文献
98.
Chao Fang Jian‐Ping Ma Sui Wei Yu‐Bin Dong 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(2):m35-m38
1,1′‐[(Ethane‐1,2‐diyldioxy)di‐o‐phenylene]bis(indoline‐2,3‐dione), C32H24N2O6, L or (I), adopts a trans conformation with the two terminal indoline‐2,3‐dione groups located on opposite sides of the central ether bridge, as required by a centre of inversion located at the mid‐point of the ethane C—C bond. However, in the discrete binuclear AgI metallocycle complex salt bis{μ‐1,1′‐[(ethane‐1,2‐diyldioxy)di‐o‐phenylene]bis(indoline‐2,3‐dione)}disilver(I) bis(hexafluoridoantimonate), [Ag2(C32H24N2O6)2][SbF6]2, (II), synthesized by combination of L with AgSbF6, L adopts a gauche conformation to bind AgIvia the two indolinedione O atoms and two C atoms from the phenoxy ring. One dione O atom from the opposite side of the ether bridge completes the irregular coordination environment of each AgI atom. The complex is on a centre of inversion located between the AgI atoms. In the solid state, these binuclear [Ag2L2]2+ metallocycles stack together via intermolecular π–π interactions to generate a one‐dimensional chain motif, with the [SbF6]− counter‐ions, which are disordered, located between the chains. 相似文献
99.
100.
Given an arbitrary real quartic polynomial, we find the exact region containing the coefficients of the polynomial such that
all roots have absolute values less than 1. 相似文献