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71.
合成了含Mo(0)的三核化合物(Et4N)2[(CO)4Mo(μ-S)2Mo(μ-S)2Mo(CO)4](Ⅰ)和(Et4N)2[(CO)4Mo(μ-S)2W(μ-S)2Mo(CO)4](Ⅱ),测定了(Ⅰ)的晶体结构.Ⅰ属单斜晶系,空间群P2相似文献
72.
73.
K. W. Cheah L. C. Ho J. B. Xia J. Li W. H. Zheng W. R. Zhuang Q. M. Wang 《Applied Physics A: Materials Science & Processing》1995,60(6):601-606
Photoluminescence studies on porous silicon show that there are luminescence centers present in the surface states. By taking photoluminescence spectra of porous silicon with respect to temperature, a distinct peak can be observed in the temperature range 100–150 K. Both linear and nonlinear relationships were observed between excitation laser power and the photoluminescence intensity within this temperature range. In addition, there was a tendency for the photoluminescence peak to red shift at low temperature as well as at low excitation power. This is interpreted as indicating that the lower energy transition becomes dominant at low temperature and excitation power. The presence of these luminescence centers can be explained in terms of porous silicon as a mixture of silicon clusters and wires in which quantum confinement along with surface passivation would cause a mixing of andX band structure between the surface states and the bulk. This mixing would allow the formation of luminescence centers. 相似文献
74.
Wen-bao Li Ya-hui Zhuang Dai-zheng Liao Geng-ling Wang 《Transition Metal Chemistry》1994,19(3):315-318
Summary Two -phenoxo-bridged binuclear copper(II) complexes, [Fsal(GG)2Cu2Cl3]·H2O (1) containing an exogenous chloride-bridge and [Fsal(GG)2Cu2(OH)](ClO4)2·H2O (2) containing an exogenous hydroxide-bridge, where {Fsal(GG)2 = 2,6-bis[N-(acetylglycine)-imino-methylene]-4-methylphenol}, were synthesized. The complexes were characterized be several spectroscopic methods. According to variable temperature magnetic susceptibility measurements (4–300 K), the hydroxide-bridged complex (2) has a weak antiferromagnetic spin exchange integral (J =- 23.6 cm), while the chloride complex (1) has an unusual weak ferromagnetic spin exchange integral (J = + 30.9 cm); both complexes have similar optical spectra in the aqueous solutions. 相似文献
75.
The kinetics of the acid catalyzed hydrolysis of 2-aminoethanethiolsulfate (AETS) ions were investigated. The dependence of the hydrolysis rate constant on acidity and temperature was determined. The hydrolysis rate equation can be expressed as where Ho is the Hammett acidity function. The rate constant, k, can be expressed as The pKa's for the compound were measured and literature value of pKa was found to be in error. The values determined in this study are pKa1 < ?0.5 and pKa2 = 9.1 ± 0.1. General acid catalysis of the hydrolysis reaction was found not to proceed to a significant degree. © 1994 John Wiley & Sons, Inc. 1 This article is a US Government work and, as such, is in the public domain in the United States of America. 相似文献
76.
Chunya Du Hui Liu Zhuang Cheng Shaoqin Zhang Zexing Qu Dezhi Yang Xianfeng Qiao Zujin Zhao Ping Lu 《Advanced functional materials》2023,33(45):2304854
The pursuit for efficient deep blue material is an ever-increasing issue in organic optoelectronics field. It is a long-standing challenge to achieve high external quantum efficiency (EQE) exceed 10% at brightness of 1000 cd m−2 with a Commission International de L'Eclairage (CIEy) <0.08 in non-doped organic light-emitting diodes (OLEDs). Herein, this study reports a deep blue luminogen, PPITPh, by bonding phenanthro[9,10-d]imidazole moiety with m-terphenyl group via benzene bridge. The non-doped OLED based on PPITPh exhibits an exceptionally high EQE of 11.83% with a CIE coordinate of (0.15, 0.07). The EQE still maintains 10.17% at the brightness of 1000 cd m−2, and even at a brightness as high as 10000 cd m−2, an EQE of 7.5% is still remained, representing the record-high result among non-doped deep-blue OLEDs at 1000 cd m−2. The unprecedented device performance is attributed to the reversed intersystem crossing process through hot exciton mechanism. Besides, the maximum EQE of orange phosphorescent OLED with PPITPh as host is 32.02%, and remains 31.17% at the brightness of 1000 cd m−2. Such minimal efficiency roll-off demonstrates that PPITPh is also an excellent phosphorescent host material. The result offers a new design strategy for the enrichment of high-efficiency deep blue luminogen. 相似文献
77.
Xiaohui Chen Niu Niu Dan Li Zicong Zhang Zeyan Zhuang Dingyuan Yan Jiangao Li Zujin Zhao Dong Wang Ben Zhong Tang 《Advanced functional materials》2023,33(8):2211571
Photoactivatable agent is a powerful tool in biomedicine studies due to high-precision spatiotemporal control of light. However, those previously reported agents generally suffer from short wavelength, fluorescence self-quenching effect, and the lack of photosensitizing property, which severely restrict their practical applications. To address these issues, molecular engineering of 1,4-dihydropyridine derivatives is conducted to obtain an optimized agent, namely TPA-DHPy-Py, which exhibits low oxidation potential, high photoactivation efficiency, and excellent type I/II combined photodynamic activity. Concurrently, its photoactivated counterpart is featured by aggregation-induced near-infrared emission and remarkable reactive oxygen species (ROS) production efficiency. Upon photoactivation, TPA-DHPy-Py is capable of precisely identifying cancer cells from co-culturing cancer cells and normal cells without the assistance of any extra targeting units, and in situ monitoring lipid droplets and endoplasmic reticulum alteration under ROS stress, as well as achieving fluorescent visualization of tumor in vivo with supremely high imaging contrast. Furthermore, the unprecedented performance on photodynamic cancer therapy is demonstrated by the significant inhibition of tumor growth. Therefore, the photoactivatable TPA-DHPy-Py with dual-organelle-targeted and excellent photodynamic activity associated with self-monitoring ability is highly promising for cancer theranostics in clinical trials. 相似文献
78.
Zhe Zhang Peng He Wenjun Ma Peiyuan Zuo Xiaoyun Liu Qixin Zhuang 《Advanced functional materials》2023,33(33):2302212
Herein, a facile, controllable, and versatile method is reported to prepare monodisperse yolk-shell and yolk-multishell silica nanoparticles (NPs) with mesoporous shells by a novel selective etching strategy. The mechanism of selective etching based on fluoride-silica chemistry is investigated in detail and thus provides a fundamentally novel principle for the fabrication of yolk-shell NPs. Specifically, this unprecedented and versatile synthesis strategy can be used to encapsulate essentially any silica-based, carbon-based, metal, metal oxide, or other possible NPs. Noteworthy is that most of the yolk-shell mesoporous silica (mSiO2) NPs are prepared for the first time. To demonstrate the major structural and compositional advantages of the designed yolk-shell NPs, their applications in the fields of ultralow-dielectric constant (k) materials, drug delivery systems, and catalysts were explored. In detail, the lowest k value of the prepared yolk-shellordered mesoporous silica@mSiO2/fluorinated polybenzoxazole composite films is 2.02; The obtained yolk-shell mSiO2/C@mSiO2/C NPs possess high hydrophilicity and pH-responsive sensitivity; The conversion of the catalytic reaction of the designed magnetic yolk-shell hollow Fe3O4@SiO2/Au@mSiO2 NPs at 20 min is 97% with a high conversion rate (92%) and recyclability even after 10 reuses. This innovative work lays a solid foundation for freely tailorable yolk-shell encapsulation and will greatly stimulate more efforts devoted to relevant research and development. 相似文献
79.
SynthesisandStructureof[(C_2H_5)_4N][Mo_3(μ_3-O)(μ-Cl)_3(μ-CH_3CH_2COO)_3Cl_3]ZhuangHong-Hui;WuDing-Ming;HuangJian-Quan;HuangJin-L... 相似文献
80.
Jian Zhuang Julius M. Hastings Lester M. Corliss R. Bau Chiau-Yu Wei R. O. Moyer Jr. 《Journal of solid state chemistry》1981,40(3):352-360
Neutron diffraction data have been collected on a powdered sample of Sr2IrD5 over a range of temperatures. The compound, which is cubic at room temperature, has been found to exhibit a gradual transformation to a tetragonal phase in the temperature range 200-140 K. As a result of the transition, deuterium atoms which randomly occupy sixfold positions in the cubic phase, become tetragonally ordered. A small fraction of the cubic phase remained untransformed at 4.2 K. Both the cubic and tetragonal structures are consistent with square pyramidal IrD5 units with average Ir---D distances of 1.714 and 1.718 Å, respectively. Agreement factors, R1, for the two structural analyses are 3.44 and 4.94%. 相似文献