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排序方式: 共有7514条查询结果,搜索用时 15 毫秒
121.
PreparationandCrystalStructureofPrNb_5O_(14)¥MaoJiang-Gao;ZhuangHong-Hui;HuangJin-Shun(StateKeyLaboratoryofStructuralChemistry... 相似文献
122.
Sarmiento M Mooney P Bishop JM Biswas N Cason NM Dauwe L Godfrey J Kenney VP Pemper R Rojek E Ruchti RC Shephard WD Edelstein RM Forsyth CP Gamarnik K Ginther G Kreymer AE Lipton R McQuade JM Potter DM Russ JS Spiegel L Johnson DE Buchholz D Cremaldi L Delchamps SW Mao HS Rosen JL Sakumoto W Schluter RA Sontz SB Winter C 《Physical review D: Particles and fields》1992,45(7):2244-2248
123.
124.
聚丙烯酰胺对石油磺酸盐/正丁醇混合胶束体系流变性的影响 总被引:1,自引:0,他引:1
研究了一定矿化度下,不同分子量、不同水解度的聚丙烯酰胺对石油磺酸盐/正丁醇混合胶事体系的流型、粘度等充变性质的影响。 相似文献
125.
Structural transformation of molecular nitrogen to a single-bonded atomic state at high pressures 总被引:1,自引:0,他引:1
Eremets MI Gavriliuk AG Serebryanaya NR Trojan IA Dzivenko DA Boehler R Mao HK Hemley RJ 《The Journal of chemical physics》2004,121(22):11296-11300
The transformation of molecular nitrogen to a single-bonded atomic nitrogen is of significant interest from a fundamental stand point and because it is the most energetic non-nuclear material predicted. We performed an x-ray diffraction of nitrogen at pressures up to 170 GPa. At 60 GPa, we found a transition from the rhombohedral (R3c) epsilon-N(2) phase to the zeta-N(2) phase, which we identified as orthorhombic with space group P222(1) and with four molecules per unit cell. This transition is accompanied by increasing intramolecular and decreasing intermolecular distances. The major transformation of this diatomic phase into the single-bonded (polymeric) phase, recently determined to have the cubic gauche structure (cg-N), proceeds as a first-order transition with a volume change of 22%. 相似文献
126.
Mao Jia-Jun Wang Li-Juan Chen Yu-De 《Journal of Radioanalytical and Nuclear Chemistry》1988,120(2):393-400
A study of the synergistic extraction of uranium(VI) from sulphuric acid solution with 1-phenyl-3-methyl-4-(2-chlorobenzoyl)-pyrazolone-5 (PMCBP) together with di-(2-ethylhexyl)-phosphoric acid (HDEHP) and also mono-(2-ethylhexyl)-2-ethylhexyl-phosphate (HEHEHP) is described. The results suggest that the compositions of the extracted species is UO2XHA2 and UO2X2H2A2 respectively. Models for the extraction mechanism is also discussed. 相似文献
127.
Mao Jiang-Gao 《结构化学》1994,(5)
Preparation and Crystal Structures of LaCl_3(12-crown-4)(MeOH)and[LaCl_3(phen)_2(H_2O)]·MeOHMaoJiang-Gao(FujianInstituteofResea... 相似文献
128.
Surface-enhanced Raman scattering in the ultraviolet spectral region: UV-SERS on rhodium and ruthenium electrodes 总被引:3,自引:0,他引:3
Ren B Lin XF Yang ZL Liu GK Aroca RF Mao BW Tian ZQ 《Journal of the American Chemical Society》2003,125(32):9598-9599
We report the first observation of surface-enhanced Raman scattering (SERS) excited with ultraviolet (UV) light from transition metal electrodes. Adsorbed pyridine and SCN- on rough rhodium (Rh) and ruthenium (Ru) electrodes, respectively, have been studied using 325 nm laser excitation. In contrast, the best enhancers in the visible and near infrared, silver and gold, do not produce UV-SERS. The experimental data of UV-SERS are in agreement with our preliminary theoretical calculation based on the electromagnetic enhancement mechanism. The enhancement factor is about 2 orders of magnitude for the Rh and Ru electrodes when they are excited at 325 nm. 相似文献
129.
130.
Tiantian Liu Xiaojie Chen Juan Zhao Weichun Wei Zhu Mao William Wu Shibo Jiao Yang Liu Zhiyong Yang Zhenguo Chi 《Chemical science》2021,12(14):5171
Pure organic emitters with full utilization of triplet excitons are in high demand for organic light-emitting diodes (OLEDs). Herein, through modulation of electron donors and introduction of phenyl rings as π spacers, we present three pure organic fluorophores (BCz, BTCz and BPTCz) with the hybridized local and charge-transfer (HLCT) excited state feature for OLED fabrication. Importantly, the introduction of π spacers in BPTCz not only enhances locally excited character with a fast radiative decay but also promotes intermolecular interactions to suppress non-radiative decays, contributing to a high solid-state fluorescence efficiency over 90%. Significantly, BPTCz not only endows its doped OLEDs with an external quantum efficiency (EQE) up to 19.5%, but also its non-doped OLED with a high EQE of 17.8%, and these outstanding efficiencies are the state-of-the-art performances of HLCT-based OLEDs.Three purely organic fluorophores with a hybridized local and charge-transfer excited state feature are presented and enabled organic light-emitting diodes with record high external quantum efficiencies close to 20%. 相似文献