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1.
Inorg Chem ; 56(3): 1036-1040, 2017 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-28071902

RESUMO

Vapor-responsive magnetic materials are highly promising for applications as chemical switches or sensors. Compared with porous materials, nonporous species benefit in overcoming the intrinsic conflict between magnetic exchange and porosity but usually suffer from the powdering of single crystals, which hinders the understanding of the structural nature of vapor response and magnetic switch. Single-crystal-to-single-crystal (SCSC) transformation of nonporous compounds through the desorption/absorption of gaseous HCl is unprecedented. Reported here is a discrete nonporous copper(II) complex, (H3O)[K(15-crown-5)2][CuCl4], that exhibits reversible SCSC transformation and magnetic change by the chemisorption/desorption of HCl and H2O. Significant changes in the coordination number (4 ↔ 3), space group (P1̅ ↔ P21/c), color (green ↔ red), and magnetic behavior (antiferromagnetic ↔ paramagnetic) were found during the SCSC transformation.

2.
Chin Med ; 6: 40, 2011 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-22047073

RESUMO

BACKGROUND: The prevalence and risk of cardiovascular disease increase after menopause in correlation with the progression of abnormality in the serum lipid profile and the deprivation of estrogen. Erxian decoction (EXD), a Chinese medicinal formulation for treating menopausal syndrome, stimulates ovarian estrogen biosynthesis. This study investigates whether EXD improves the serum lipid profile in a menopausal rat model. METHODS: Twenty-month-old female Sprague Dawley rats were treated with EXD and its constituent fractions. Premarin was administered for comparison. After eight weeks of treatment, rats were sacrificed and the serum levels of total cholesterol, triglyceride, high-density-lipoprotein cholesterol and low-density-lipoprotein cholesterol were determined. The hepatic protein levels of 3-hydroxy-3-methyl-glutaryl-CoA reductase and low-density-lipoprotein receptor were assessed with Western blot. RESULTS: The serum levels of total cholesterol and low-density-lipoprotein cholesterol were significantly lower in the EXD-treated group than in the constituent fractions of EXD or premarin groups. However, the serum levels of triglyceride and high-density-lipoprotein cholesterol were not significantly different from the control groups. Results from Western blot suggest that EXD significantly down-regulated the protein level of 3-hydroxy-3-methyl-glutaryl-CoA reductase and up-regulated low-density-lipoprotein receptor. Conclusion EXD improves serum lipid profile in a menopausal rat model through the suppression of the serum levels of total cholesterol and low-density-lipoprotein cholesterol, possibly through the down-regulation of the 3-hydroxy-3-methyl-glutaryl-CoA and up-regulation of the low-density-lipoprotein receptor.

3.
Dalton Trans ; 39(37): 8688-92, 2010 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-20717609

RESUMO

A photochromic inorganic-organic hybrid based on in situ generated MV(2+) cation (MV(2+) = methyl viologen = N,N'-dimethyl-4,4'-bipyridinium) has been obtained, in which a vagarious partial photochromic phenomenon together with its photoluminescence modulation properties are reported for the first time in the inorganic-organic hybrids.

4.
Chem Commun (Camb) ; 46(3): 361-76, 2010 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-20066296

RESUMO

The distinct synergetic characteristics between each component in inorganic-organic hybrids offer various possibilities to obtain new "smart", high performing materials. Growing interest in this field has largely expanded the content of photochromic materials for the purpose of improving existing photochromic materials, fabricating photoresponsive devices, and exploring new families of photochromic materials. In this feature article, we give a brief review of photochromic hybrids of metal halides, metal cyanides, polyoxometalates, and metal chalcogenides as well as photochromic metal-organic complexes.

7.
Inorg Chem ; 46(18): 7321-5, 2007 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-17665902

RESUMO

A new, quaternary mercury and cadmium pnictidehalide semiconductor (Hg6Sb4)(CdI6) (1) has been prepared by the solid-state reaction and structurally characterized by single-crystal X-ray diffraction analysis. Compound 1 crystallizes in the space group R-3c of the rhombohedral system with four formula units in a cell: a=13.3818(9) A, alpha=90.93 degrees, and V=2395.3(3) A3. The crystal structural novelty of 1 derives from the fact that a 3-D mercury antimonide cationic network interpenetrates with an unusual 3-D cadmium iodide octahedral anionic network through the weak covalent interactions between mercury and iodine atoms to form a mixed 3-D framework. Among them, the cationic moiety features a perovskite-like 3-D network while the anionic moiety is characterized by a 3-D I6 octahedral anionic network with two-thirds I6 octahedra being occupied by Cd atoms. The optical properties were investigated in terms of the diffuse reflectance and Fourier transform infrared spectra. The electronic band structure along with density of states calculated by the density functional theory method indicates that compound 1 is a semiconductor with a direct band gap and that the optical absorption of 1 is mainly ascribed to the charge transitions from I-5p and Sb-5p states to Cd-5s and Hg-6s states.

9.
Inorg Chem ; 45(25): 10028-30, 2006 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-17140201

RESUMO

A novel inorganic-organic hybrid [(H2en)7(C2O4)2]n(Pb4I18)n.4nH2O has been synthesized by employing an organic anionic-cationic co-template. It shows a new type of perovskite structure, featuring an unprecedented staircase-like inorganic network. The title compound exhibits an intriguing semiconducting property with Eg = 2.47 eV and strong photoluminescence arising from band-edge transitions.

10.
Inorg Chem ; 45(16): 6365-9, 2006 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-16878947

RESUMO

A new quaternary cadmium and mercury pnictidehalide semiconductor (Hg2Cd2As2Br)Br (1) has been prepared by the solid-state reaction of HgBr2 with elemental Cd and As at 420 degrees C. Compound 1 crystallizes in the space group Pmma of the orthorhombic system with two formula units in a cell: a = 8.791(4) A, b = 4.701(2) A, c = 9.779(6) A, V = 404.2(3) A(3). The structure of 1 is composed of parallel slabs bridged by linearly coordinated Hg atoms to form a 3D cationic network with the channels occupied by discrete Br anions, in which the layer consists of interlinks of linear (HgAs2Br2) tetrahedral chains and (CdAs2Br) trigonal chains. The optical properties were investigated in terms of the diffuse reflectance and Fourier transform infrared spectra. The electronic band structure along with the density of states (DOS) calculated by the DFT method indicate that compound 1 is a semiconductor with an indirect band gap and that the optical absorption mainly originates from the charge transitions from the Br2-4p and As-4p to Cd-5s and Hg-6s states.

11.
Inorg Chem ; 45(5): 1972-7, 2006 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-16499358

RESUMO

A new type of one-dimensional organic-inorganic hybrid [M(en)3]Pb2I6 [M = Mn (1), Fe (2), Zn (3), Ni (4); en = ethylenediamine] has been obtained and structurally characterized by X-ray crystallography, which opens a new approach to construct hybrid magnetic semiconductors. The results of optical absorption spectra and theoretical calculations for compounds 1-3 reveal a quantum confinement effect, and the variable-temperature magnetic susceptibility measurements for 1, 2, and 4 indicate ferromagnetic, antiferromagnetic, and paramagnetic behavior, respectively.

12.
Dalton Trans ; (7): 884-6, 2006 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-16462947

RESUMO

The reactions of silver(I) cyanide with tetraalkylammonium salts in anhydrous tetrahydrofuran (THF) under solvothermal conditions and then diffused with ether lead to two novel mixed halogeno(cyano)argentates(I) with efficient luminescence.

13.
Inorg Chem ; 44(2): 184-6, 2005 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-15651862

RESUMO

Two transition-metal tetrathioarsenate complexes, [Mn(dien)(2)](n)[Mn(dien)AsS(4)](2n).4nH(2)O (1) with one-dimensional water chain and [Mn(en)(3)](2)[Mn(en)(2)AsS(4)][As(3)S(6)] (2) with mixed-valence As(3+)/As(5+) character, have been synthesized and structurally characterized. The tetrathioarsenate(V) anion acts as a novel mu(2)-eta(1),eta(2) ligand in 1 and as a chelating ligand in 2. The two compounds exhibit intriguing semiconducting properties (E(g) = 2.18 eV (1), 2.48 eV (2)) and strong photoluminescence with the emission maximum occurring around 440 nm.

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