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排序方式: 共有373条查询结果,搜索用时 62 毫秒
81.
Avery P Freyberger A Rodriguez J Yelton J Henderson S Kinoshita K Pipkin F Saulnier M Wilson R Wolinski J Xiao D Yamamoto H Sadoff AJ Ammar R Baringer P Coppage D Davis R Kelly M Kwak N Lam H Ro S Kubota Y Nelson JK Perticone D Poling R Schrenk S Alam MS Kim IJ Nemati B Romero V Sun CR Wang P Zoeller MM Crawford G Fulton R Gan KK Jensen T Kagan H Kass R Malchow R Morrow F Whitmore J Wilson P Butler F Fu X Kalbfleisch G Lambrecht M Skubic P Snow J Bortoletto D Brown DN Dominick J McIlwain RL 《Physical review letters》1992,68(9):1279-1282
82.
Daoudi M Ford WT Johnson DR Lingel K Lohner M Rankin P Smith JG Alexander J Bebek C Berkelman K Besson D Browder TE Cassel DG Cheu E Coffman DM Drell PS Ehrlich R Galik RS Garcia-Sciveres M Geiser B Gittelman B Gray SW Hartill DL Heltsley BK Honscheid K Kandaswamy J Katayama N Kim PC Kreinick DL Lewis JD Ludwig GS Masui J Mevissen J Mistry NB Nandi S Ng CR Nordberg E O'Grady C Patterson JR Peterson D Pisharody M Riley D Sapper M Selen M Worden H Worris M Avery P Freyberger A Rodriguez J 《Physical review D: Particles and fields》1992,45(11):3965-3975
83.
Ammar R Baringer P Coppage D Davis R Kelly M Kwak N Lam H Ro S Kubota Y Lattery M Nelson JK Perticone D Poling R Schrenk S Wang R Alam MS Kim IJ Nemati B Romero V Sun CR Wang P Zoeller MM Crawford G Fulton R Gan KK Kagan H Kass R Lee J Malchow R Morrow F Sung MK Whitmore J Wilson P Butler F Fu X Kalbfleisch G Lambrecht M Skubic P Snow J Bortoletto D Brown DN Dominick J McIlwain RL Miller DH Modesitt M Shibata EI Schaffner SF Shipsey IP Battle M Ernst J Kroha H Roberts S Sparks K Thorndike EH 《Physical review D: Particles and fields》1992,45(11):3976-3985
84.
Henderson S Kinoshita K Pipkin F Procario M Saulnier M Wilson R Wolinski J Xiao D Ammar R Baringer P Coppage D Davis R Haas P Kelly M Kwak N Lam H Ro S Kubota Y Nelson JK Perticone D Poling R Schrenk S Crawford G Fulton R Jensen T Johnson DR Kagan H Kass R Malchow R Morrow F Whitmore J Wilson P Bortoletto D Brown D Dominick J McIlwain RL Miller DH Modesitt M Schaffner SF Shibata EI Shipsey IP Battle M Kroha H Sparks K Thorndike EH Wang C Alam MS Kim IJ Li WC Nemati B Romero V Sun CR Wang P 《Physical review D: Particles and fields》1992,45(7):2212-2231
85.
Muhammad Akmal Kamarudin Ammar A. Khan Suhana Mohd Said Malik M. Qasim Timothy D. Wilkinson 《Liquid crystals》2018,45(1):112-121
The doping of polymer electrolytes (PEs) with liquid crystal (LC) materials has been shown to improve the performance of dye-sensitised solar cells (DSSCs). This is achieved by promoting ionic conduction and increasing optical path length through multiple-light scattering within the photovoltaic devices. In LCs, it is well known that the length of the alkyl chain plays an important role since the LC morphology and mesophase stabilisation depend strongly on the alkyl group. In this work, liquid crystal-polymer composite electrolytes (LC-PEs) are prepared using nematic LCs with different alkyl chain lengths. The morphology of the LC-PEs is investigated and correlated with their electrical properties. Subsequently, DSSCs are prepared using the LC-PEs as a direct example of its application. It is shown that increasing the alkyl chain length of the LCs reduces the efficiency of the solar devices. The longer alkyl chains are speculated to intertwine, thus trapping the mobile ions and reducing the bulk ionic conductivity. For the same reason, longer alkyl chain LCs are thought to be unable to passivate the TiO2 surface through the adsorption of cyanobiphenyl groups and hence the higher probability of back recombination reaction between the electrons in TiO2 and PE. 相似文献
86.
In this study, combined technique of solid-phase extraction based on multi-walled carbon nanotubes with bio-coacervation extraction (SPE-MWCNT-BCAE) has been developed as a new sample preparation method for the determination of atrazine from water samples. The proposed method involves two steps: analyte enrichment on the solid sorbent and subsequently elution of the analyte by an appropriate solvent. Multi-walled carbon nanotubes (MWCNTs) were used as the sorbent. They have high specific surface area, nano-scale structure and high diffusion rate. The second step is based on the use of bioaggregates for analyte re-enrichment, which consists of biosurfactants and ionic liquid. This method follows the principles of green chemistry. Parameters affecting the extraction efficiency were optimized. Under optimum conditions, the enrichment factor was 176. The linear dynamic range (LDR) and limit of detection (LOD) were 2–100 µg L?1 and 0.66 µg L?1, respectively. The relative standard deviation (RSD) for six replicate measurements was 3.8%. The method was applied to the determination of ultratrace levels of atrazine in environmental water samples with satisfactory results. 相似文献
87.
Alexander J Artuso M Bebek C Berkelman K Browder T Cassel DG Cheu E Coffman DM Crawford G DeWire JW Drell PS Ehrlich R Galik RS Gittelman B Gray SW Halling AM Hartill DL Heltsley BK Kandaswamy J Katayama N Kreinick DL Lewis JD Ludwig GS Mistry NB Mueller J Nandi S Nordberg E O'Grady C Peterson D Pisharody M Riley D Sapper M Selen M Silverman A Stone S Worden H Worris M Sadoff AJ Avery P Besson D Garren L Yelton J Bowcock T Kinoshita K Pipkin FM Procario M Wilson R Wolinski J Xiao D Zhu Y 《Physical review letters》1990,65(13):1531-1534
88.
Bowcock T Kinoshita K Pipkin FM Procario M Wilson R Wolinski J Xiao D Ammar R Baringer P Coppage D Haas P Lam H Jawahery A Park CH Kubota Y Nelson JK Perticone D Poling R Chen W Dominick J McIlwain RL Miller DH Ng CR Schaffner SF Shibata EI Yao W Sparks K Thorndike EH Alam MS Kim IJ Li WC Lou XC Sun CR Fulton R Hempstead M Jensen T Johnson DR Kagan H Kass R Morrow F Whitmore J Bortoletto D Goldberg M Horwitz N Mestayer MD Moneti GC Sharma V Shipsey IP Skwarnicki T Csorna SE Letson T Alexander J 《Physical review D: Particles and fields》1990,41(3):805-808
89.
1,3-Diphenyl-5-imino-2-imidazolidinone-4-thione (II) was treated with diazomethanes to give (III-V). Interaction of (II) with amino compounds furnished the corresponding 4-substituted imino derivatives (VIa-m). Imidazoquinoxaline derivatives (VIIIb, c) were obtained through interaction of (II) with o-phenylenediamines. Condensation of (II) with hydrazines afforded the hydrazones (IX, Xa, b). Semicarbazone and thiosemicarbazone derivatives (XIIa-d) were prepared from the reaction of (IX) with isocyanates and isothiocyanates. Again (II) was allowed to react with n-butylmagnesium bromide and HgCl2 to give (XIII) and (XIV) respectively. 相似文献
90.
A. S. Shalabi M. A. Kamel H. Y. Ammar 《International journal of quantum chemistry》2005,103(4):432-448
The FA1:Cs+ and FA2:Li+ color centers at the low coordination (100) and (110) surfaces of AgCl and AgBr play important roles in laser light generation and color image formation. Double‐well potentials at these surfaces are investigated by using ab initio calculations. Quantum clusters were embedded in the simulated Coulomb fields that closely approximate the Madelung fields of the host surfaces, and ions that are the nearest neighbors to the FA ? defect site are allowed to relax to equilibrium. The calculated Stokes shifts suggest that laser light generation is sensitive to the simultaneous effects of the vibrational coupling mode, the impurity cation, the coordination number of the surface ion, the lattice anion, and the choice of the basis set centered on the anion vacancy. An attempt has been made to explain these effects in terms of Madelung potential, electron affinity, and optical–optical conversion efficiency. All relaxed excited states of the defect‐containing surfaces are deep below the lower edges of the conduction bands of the ground‐state defect‐free surfaces, suggesting that the FA(I):Cs+ and FA(II):Li+ centers are suitable laser defects. The dependence of orientational destruction, recording sensitivity, and exciton (energy) transfer on the empty cation; the coordination number of the surface ion; and the lattice anion is clarified. The Glasner–Tompkins empirical rule was generalized to include the impurity cation and the coordination number of the surface ion. As far as color image formation is concerned, the supersensitizer was found to increase the sensitizing capabilities of two primary dyes in the excited states by increasing the relative yield of quantum efficiency. The (110) surfaces of AgBr and AgCl were more sensitive than the corresponding (100) surfaces, and AgBr thin film was found to be more sensitive than that of AgCl. On the basis of quasi‐Fermi levels, the difference in the sensitizing capabilities between the examined dyes in the excited states is determined. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 相似文献