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91.
Sreenu K. Sudhakar Reddy CH. Reddy J. R. Velchuri Radha Palla Suresh Vithal M. 《Research on Chemical Intermediates》2016,42(6):5765-5777
Research on Chemical Intermediates - Substitutional doping of framework heteroatoms in photocatalysis is one of the approaches for harvesting visible light. Tunnel structure potassium antimony... 相似文献
92.
Structural correlation in a series of eight silver(I) complexes bearing substituted phenylethynide ligands was systematically investigated through variation of the position or steric bulk of substituents on the aromatic ring. All coordination frameworks are constructed with the supramolecular synthon Ar--C triple bond C superset Ag(n) (Ar=4-MeC6H4, 3-MeC6H4, 2-MeC6H4, 4-tBuC6H4, 3,5-(CF3)2C6H3; n=4, 5), and the presence of coexisting ligands was found to influence the supramolecular assembly. The role of pi-pi stacking, C--Hpi and Ag-C(aromatic) interactions in stabilizing the coordination networks is also discussed. 相似文献
93.
Chi Ching Mak Nick Bampos Jeremy K. M. Sanders 《Angewandte Chemie (International ed. in English)》1998,37(21):3020-3023
Rigid and flexible linkers are combined in the new dendrimer shown schematically in the picture, which contains nine metalloporphyrin units (Porph). The construction is such that the four “arms” of the dendrimer can fold in a cooperative and predetermined manner in response to added 1,4-diazabicyclo[2.2.2]octane (DABCO). 相似文献
94.
Guo-Cong Guo Thomas C. W. Mak 《Angewandte Chemie (International ed. in English)》1998,37(23):3268-3270
Layers of face- and edge-sharing trigonal Ag 6 prisms , of which half are filled with azide units, are contained in the novel compound AgN3⋅2 AgNO3 (see structure). Pendant η1-nitrate groups are attached to both sides of each layer. 相似文献
95.
96.
Chun-Kiu Kwok Thomas C. W. Mak 《Journal of inclusion phenomena and macrocyclic chemistry》1988,6(5):461-471
N,N-DicyclohexylpiperazineN,N-dioxide octahydrate, C16H46N2O10,M
r=426.55, monoclinic, space groupC2/m (No. 12),a=12.961(4),b=11.533(4),c=7.907(1) Å, =98.37(2)o,V=1169.3(6) Å3,Z=2. The structure was solved by the direct method and refined toR=0.045 for 1192 observed MoK
reflections. TheN,N-dioxide molecule occupies a site of symmetry 2/m. The piperazine ring takes the chair form with the two N–O bonds oriented axially in atrans configuration. Hydrogen bonding between the water molecules, as well as between theN-oxide groups and water molecules, gives rise to a puckered layer composed of edge-sharing four-membered, five-membered, six-membered, and eight-membered rings. Adjacent layers are cross-linked by theN,N-dicyclohexylpiperazine moieties lying between them, thereby generating a sandwich structure consolidated by covalent and hydrogen bonding.
Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82062 (8 pages). 相似文献
97.
Acoustical measurements based on impulse responses have been made in a Protestant and a Catholic church in Hong Kong. Analysis has concentrated on reverberation time, early decay time and C80, the early-to-late ratio, as well as integrated decays. The measured results have been compared with predictions according to two different theoretical room acoustic models: a model for a single diffuse space and one for a set of coupled-rooms. The comparison has shown that treating the churches as a series of coupled spaces is more valid. However the clarity, C80, at different receiver positions was found to be either under- or over-estimated by the classical coupled-room model. Following this observation, a delayed coupled-room model was developed in the hope of achieving more accurate predictions. In this model, the initial condition under the impulse excitation was modified by introducing a time delay for sound propagated from the source to achieve diffuse sound fields in each subspace. The predicted results of the coupled-room model agree well with the measured results. 相似文献
98.
Novel mu(5)-eta(1),eta(1),eta(1),eta(1),eta(2) and mu(5)-eta(1),eta(1),eta(1),eta(2),eta(2) coordination modes of alkyl and aryl ethynide moieties are found in silver(I) complexes 1-5, and the metal-ligand distances can be classified into sigma, pi and mixed (sigma,pi) types. With the consistent square-pyramidal capping Ag(5) baskets of the ethynide moiety as supramolecular synthons, a series of two- and three-dimensional coordination networks are obtained. 相似文献
99.
A C(3)-symmetric Schiff-base example of the new simple, low cost, highly water soluble, and sensitive turn-on fluorescent Zn(2+) chemosensor is described. The sensor was successfully applied to the detection of intracellular Zn(2+). Moreover, the sensor could also serve as a potential recyclable component in sensing materials. Notably, the color change is so obvious that all of the recycling process can be seen clearly by the naked eye. 相似文献
100.
Sun XL Song WC Zang SQ Du CX Hou HW Mak TC 《Chemical communications (Cambridge, England)》2012,48(15):2113-2115
The hierarchical assembly of a homochiral triple concentric helical system in a novel 3D metal-organic framework with SHG activity has been observed. The result also provides a better understanding of host-guest chemistry and the process of water transport in biological systems. 相似文献