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1.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(3): 625-9, 2014 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-25208378

RESUMO

In-doped ZnO nanopowders were prepared by precipitation. The influence of the processing parameters, such as In doping concentration, calcination temperature, reactant ratio and type of precipitant on the grain size, structure and photolumines cence (PL) of In/ZnO nanopowders was detailed analyzed by using X-ray diffraction (XRD) and photoluminescence spectrum. The experimental results indicated that with the increase in the In doping level (the molar ratio of In3+ /Zn2+ increased from 0%. to 5%), the crystallization and the UV emission of ZnO nanopowders were reduced because of the increase of impurity defects. And the UV emission band would have a red-shift from 389 to 419 nm, which could be resulted from the effects of merging of donor and conduction bands, and potential fluctuations of impurity energy level. The calcination temperature will play an important role in synthesis of luminescence materials. When the calcination temperature was raised from 500 to 600 degrees C, the grain size of In/ZnO nanopowder increased gradually, and the dominated UV emission band was improved due to the enhanced crystallization of the nanopowder. If the temperature was raised up to 800 degrees C, the crystallization of the sample was further improved, leading to an enhanced intensity of UV emission Additionally, near this temperature, the oxygen vacancy is easier to be produced owing to the improvement of the kinetic energy for the ions in lattice, which induces in the enhancement of the green emission band peaking at 525 nrn. For the temperature up to 1,000 degrees C, the UV emission band was suppressed due to the production of excessive oxygen vacancy, and the In/ZnO nanopowder exhibited a dominated green emission. The luminescence performance of the In/ZnO nanopowder is also much affected by the reactant ratio. The reaction rate is improved by the increase of the NH4 HCO3 / Zn(NO3)2 molar ratio, which will decrease both grain size of In/ZnO nanopowder and emission intensity of UV band. Furthermore, the effect of the precipitant on the luminescence was examined. It is obviously that the NH4 HCO3 and NaOH precipitants will remarkably affect the crystallization of the precursor powder, but nearly have no effect on the luminescence property of the final nanopowder products.

2.
Int J Biol Macromol ; 61: 312-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23916647

RESUMO

The objective of this study was to investigate the effect of chitosan (CH) film incorporated with tea polyphenol (TP) on quality and shelf life of pork meat patties stored at 4±1 °C for 12 days. The microbiological, physicochemical (pH, thiobarbituric acid-reactive substances (TBARS) values, and metmyoglobin (MetMb)), and sensory qualities were measured on all the samples. A microbiological shelf-life extension of 6 days was achieved for CH and CH-TP treatment groups when compared to the control group. Wrapping with CH-TP composite film tended to retard the increases in TBARS values and MetMb content. CH-TP composite film maintained acceptable sensory quality of pork meat patties throughout the storage. The results indicated that CH-TP composite film could be a promising material as a packaging film for extending the shelf life of pork meat patties.


Assuntos
Quitosana/química , Produtos da Carne/normas , Carne/normas , Polifenóis/química , Chá/química , Animais , Embalagem de Alimentos , Conservação de Alimentos , Concentração de Íons de Hidrogênio , Lipídeos/química , Carne/microbiologia , Produtos da Carne/microbiologia , Metamioglobina/química , Suínos , Fatores de Tempo
3.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 9): m1123, 2009 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-21577464

RESUMO

In the title coordination polymer, [CuI(C(14)H(18)N(4)S(2))](n), the Cu(I) center is trigonally coordinated by two pyrimidine N-atom donors from two distinct dithio-ether ligands and one iodide anion. The Cu and I atoms are located on a twofold axis, whereas the midpoint of the central C-C bond of the dithio-ether ligand is located on an inversion center. Each organic ligand, acting in a bidentate mode, bridges two Cu(I )ions, resulting in the formation of polymeric zigzag chains. The dihedral angle between the two pyrimidine units bonded to the metal center is 88.01 (2)°. The crystal packing is mainly stabilized by van der Waals forces and π-π stacking inter-actions, with an inter-planar distance between the pyrimidine rings of adjacent chains of 3.638 (3) Å.

4.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 8): m1013, 2008 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-21203007

RESUMO

The asymmetric unit of the title compound, [Pt(C(23)H(17)N(2))Cl], contains two independent mol-ecules with distinct dihedral angles between the central pyridyl and methylbenzene rings [7.77 (2) and 24.07 (2)°]. Short inter-molecular distances [3.582 (6) and 3.600 (6) Å] between the outer pyridine and the PtNC(3) and PtN(2)C(2) rings, respectively, indicate the existence of π-π inter-actions, which link the mol-ecules into stacks along the a axis. The crystal structure is further stabilized by weak C-H⋯π inter-actions.

5.
Zhonghua Gan Zang Bing Za Zhi ; 13(12): 930-2, 2005 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-16381643

RESUMO

OBJECTIVE: To study the pathological changes of the liver tissues of patients with HIV infection. METHODS: 14 biopsy and 12 autopsy liver tissues were examined histologically. HIV-1 related antigen of outer membrane protein gp120 and capsid protein p24 were examined with their corresponding monoclonal antibodies by immunohistochemistry. RESULTS: In the biopsy group, cytomegalic virus (CMV) infection was found in one (1/14) case, outer membrane protein gp120 and/or capsid protein p24 antigen were detected in Kupffer cells and in some of the lymphocytes in 11 cases. All the hepatocytes were negative for outer membrane protein gp120 and capsid protein p24 antigens. In the autopsy group, there were 5 (5/12) cases of liver tissues with CMV infection and 5 cases each with mycobacterium and Toxoplasma gondii infection. Capsid protein p24 was detected in liver tissues in 3 cases. CONCLUSION: There is HIV infection in liver tissue of patients with HIV. The rate of opportunistic infections in liver biopsy samples was lower than that in the autopsy liver tissues of patients with HIV.


Assuntos
Infecções por HIV/patologia , Fígado/patologia , Adulto , Feminino , Proteína do Núcleo p24 do HIV/biossíntese , Proteína do Núcleo p24 do HIV/genética , Proteína gp120 do Envelope de HIV/biossíntese , Proteína gp120 do Envelope de HIV/genética , Humanos , Masculino , Pessoa de Meia-Idade
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