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51.
On analyzing the topological structures of the three types of tetrahedral fullerenes (which consist only of triangles and
hexagons), (1) C
n
(T
d
,n=12h
2; h=1,2,…), (2) C
n
(T
d
,n=4h
2;h=1,2,…), and (3) C
n
(T,n=4(h
2+hk+k
2);h>k,h,k=1,2,…), we have obtained theoretically the Infrared and Raman active modes by means of the derived formulas for the decomposition
of their nuclear motions into irreducible representations, and the 13C NMR spectra with natural abundance for 13C by using the distribution functions for all of the tetrahedral (T
d
and T) fullerenes, respectively.
Received: 25 May 1998 / Accepted: 30 July 1998 / Published online: 23 November 1998 相似文献
52.
53.
54.
On the bases of the topological structures of the three big classes of icosahedral fullerenes: (1) Cn(Ih, n=60h2; h=1, 2,…), (2) Cn(Ih, n=20h2; h=1, 2,…), and (3) Cn(I, n=20(h2+hk+k2), h>k; h, k=1, 2,…), we derived formulas for the decomposition of their nuclear motions into irreducible representations. Hence, we obtained the infrared and Raman active modes for all of the icosahedral (Ih and I) fullerenes theoretically. © 1998 John Wiley & Sons, Inc. Int J Quant Chem 66 : 113–117, 1998 相似文献
55.
Wei Zhou Jun-Kang Guo Sheng Shen Jinbo Pan Jie Tang Lang Chen Chak-Tong Au Shuang-Feng Yin 《物理化学学报》2020,36(3):1906048-0
CO_2是最常见的化合物,作为潜在的碳一资源,可用于制备多种高附加值的化学品,如一氧化碳、甲烷、甲醇、甲酸等。传统的热催化转化CO_2方法能耗高,反应条件苛刻。因此,如何在温和条件下高效地将CO_2转化成高附加值的化学品,一直以来是催化领域的研究热点和难点之一。光催化技术反应条件温和、绿色环保。然而,纯光催化反应普遍存在太阳能利用效率有限,光生载流子分离效率低等问题。针对上述问题,在光催化的基础上引入电催化,可以提高载流子的分离效率,在较低的过电位下,实现多电子、质子向CO_2转移,从而提高催化反应效率。总之,光电催化技术可以结合光催化和电催化的优势,提高CO_2催化还原反应效率,为清洁、绿色利用CO_2提供了一种新方法。本文依据光电催化CO_2还原反应基本过程,从光吸收、载流子分离和界面反应等三个角度综述了光电催化反应的基本强化策略,并对未来可能的研究方向进行了展望。 相似文献
56.
C.K. Au 《Physics letters. A》1975,51(7):442-444
Recent experimental technology points to the possibility of measuring the 2S–3S transition in hydrogen-like atoms via two-photon absorption. The non-relativistic amplitude for this process is evaluated exactly and numerical values are given. 相似文献
57.
Dual Esterase‐ and Steroid‐Responsive Energy Transfer Modulation of Ruthenium(II) and Rhenium(I) Complex Functionalized Gold Nanoparticles 下载免费PDF全文
Dr. Frankie Chi‐Ming Leung Dr. Vonika Ka‐Man Au Dr. Hai‐Ou Song Prof. Dr. Vivian Wing‐Wah Yam 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(46):16448-16454
A number of adamantane‐containing ruthenium(II) and rhenium(I) complexes have been synthesized, characterized, and noncovalently functionalized with β‐cyclodextrin‐capped gold nanoparticles (β‐CD–GNPs) through the host–guest interaction between cyclodextrin and adamantane. The resultant nanoconjugates have been characterized by transmission electron microscopy (TEM), energy‐dispersive X‐ray analysis (EDX), and 2D ROESY 1H NMR experiments. The Förster resonance energy transfer (FRET) properties of the nanoconjugates can be modulated by both esterase‐accelerated hydrolysis and competitive displacement of steroid, by monitoring the emission intensity and luminescence lifetime. The FRET efficiencies are found to vary with the nature of the chromophores and the length of the spacer between the transition metal complexes and the GNPs. This work constitutes a “proof‐of‐principle” assay method for the dual‐functional detection of important classes of biomolecules, such as enzymes and steroids. 相似文献
58.
A novel organoantimony complex of 6-cyclohexyl-6,7-dihydrodibenzo[c,f] [1,5]azastibocin-12(5H)-yl nitrate ( 2 ) was synthesized and systematically characterized by techniques such as NMR spectra, TG-DSC, and X-ray diffraction. It was found that the complex 2 exhibits relatively strong Lewis acidity (3.3 < Ho ≤ 4.8) and could be employed as a water tolerant Lewis acid catalyst for the synthesis of synthetically valuable benzimidazole derivatives starting from aldehydes and arylenediamines. This catalytic system shows excellent tolerance toward a wide variety of functional groups, such as methyl, methoxyl, fluoro, chloro, bromo, nitro, cyan, trifluoromethyl, 1-naphthaldehyde, furfural and n-butyl, together with facile reusability in 5 times scale enlarged synthesis. 相似文献
59.
Hao‐Hao Wang Yi‐Xiang J. Wang Prof. Ken Cham‐Fai Leung Prof. Doris W. T. Au Prof. Shouhu Xuan Dr. Chun‐Pong Chak Simon K. M. Lee Dr. Hui Sheng Dr. Ge Zhang Dr. Ling Qin Prof. James F. Griffith Prof. Anil T. Ahuja Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(45):12417-12425
Small polyhedral superparamagnetic iron oxide (SPIO) nanoparticles (<10 nm) coated with a thin layer of silica were prepared (SPIO@SiO2 and SPIO@SiO2‐NH2). Surface modification of the small polyhedral silica‐coated SPIO nanoparticles with amines led to substantially higher mesenchymal stem cell (MSC) labelling efficiency without the use of additional transfecting agents. Therefore, amine surface‐modified nanoparticles (SPIO@ SiO2‐NH2) appeared to be the preferred candidate for MSC labelling. In vitro studies demonstrated that controlled labelling of SPIO@SiO2 and SPIO@SiO2‐NH2 did not cause MSC death or proliferation inhibition. MSCs labelled with SPIO@SiO2‐NH2 nanoparticles retained differentiation potential and showed osteogenic, adipogenic and chondrogenic differentiations. The noncytotoxic polyhedral SPIO@SiO2‐NH2 nanoparticle‐labelled MSCs were successfully implanted in rabbit brain and erector spinae muscle, and demonstrated long‐lasting, durable MRI labelling efficacy after 8–12 weeks. 相似文献
60.
We demonstrate the possibility of serially guiding and sorting nanometer-sized particles without the use of any external control. The working principle is based on an equilibrium between scattering and binding forces, the latter depending on the properties of the particles. A configuration is proposed that utilizes this property and is shown to efficiently sort small particles as function of their size. 相似文献