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1.
Zootaxa ; 4742(1): zootaxa.4742.1.13, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32230400

RESUMO

Larvae of a previously unknown species of gall midge were found causing large numbers of pustulate leaf galls on Peking lilac, Syringa reticulata subsp. pekinensis (Oleaceae), in parklands and street greenery in Beijing, China. Heavily galled leaves become senescent and fall off prematurely. The gall midge is named Pekinomyia syringae Jiao Kolesik, its morphology is described and the COI mitochondrial gene and 12S ribosomal gene segments are sequenced. A new genus, Pekinomyia Jiao Kolesik (Cecidomyiinae: Lasiopteridi), is erected for the new species. The new genus differs from other Lasiopteridi in the strongly sclerotized aedeagus and the lack of mesobasal lobes in the male terminalia and is not assigned to any known tribe.


Assuntos
Dípteros , Oleaceae , Syringa , Animais , Pequim , China , Masculino , Folhas de Planta
2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(8): 1207-9, 2005 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-16329481

RESUMO

The influences of surface treatments of indium-tin-oxide (ITO) anodes on the performance of OLED devices were investigated. This surface treatment is mechanical processes using a novel nanometer powder. Their surface morphology was measured by scanning using an AFM (atomic force microscope). The number and size of spike was reduced and regulation of ITO was enhanced; brightness and efficiency of devices were obviously increased. This novel way for ITO surface treatment by mechanical processes was proven to be effective.


Assuntos
Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Compostos de Estanho/química , Eletrodos , Microscopia de Força Atômica , Nanoestruturas , Pós , Reprodutibilidade dos Testes , Propriedades de Superfície
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(6): 828-31, 2005 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-16201350

RESUMO

A new rare earth complex Tb(BSA)4 was synthesized and studied. Pure green and narrow band emission was generated from the device with structure ITO/PVK:Tb(BSA)4 /Alq3 /LiF/Al, where PVK was used to improve the film-formation and hole-transport property of the Tb(BSA)4. The absorption mechanism, and the photoluminescence and electroluminescence mechanisms are discussed. It has been proved that there exists energy transfer from PVK to Tb(BSA)4 and the mechanisms of photoluminescence and electroluminescence are different. The effect of different ratios of PVK on the device characteristics is also studied.


Assuntos
Luminescência , Compostos Organometálicos/química , Salicilatos/química , Térbio/química , Medições Luminescentes/métodos , Metais Terras Raras/química , Estrutura Molecular , Compostos Organometálicos/síntese química , Polivinil/química , Espectrofotometria
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(6): 832-5, 2005 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-16201351

RESUMO

300 nm thick aluminum films were deposited on SiO2 substrates by heat evaporation. At 0 degrees C, 40 V DC voltage, the authors successfully prepared high density Al2O3 films by anodic oxidation on SiO2 substrates with 15 wt% H2SO4 as electrolyte, and AFM was employed to study the film surface morphology. At room temperature the authors measured the photoluminescence spectrum of Al2O3 films prepared at different anodic voltages excited by Xe lamp. In addition, the authors monitored their excitation spectra of different emission peaks, and the authors found that the relative emission intensity gets weaker and shifts to lower energy at higher anodic voltage. At 40 V anodic voltage the authors observed new 356 nm ultraviolet emission, which has the same 210 nm excitation emission. Based on the discussion of the relative intensity of the PL spectra of anodic alumina at different voltages, the authors suggest that F and F+ oxygen vacancy defects were responsible for the observed 356 and 386 nm ultraviolet photoluminescence from Al2O3 anodic film at 40 V voltage.


Assuntos
Luminescência , Dióxido de Silício/química , Óxido de Alumínio/química , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Medições Luminescentes/instrumentação , Medições Luminescentes/métodos , Membranas Artificiais , Microscopia de Força Atômica , Espectrometria de Fluorescência , Propriedades de Superfície
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(1): 23-5, 2005 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-15852809

RESUMO

An organic photovoltaic(PV) cell, ITO/MEH-PPV/Alq3/LiF/Al, was fabricated. The MEH-PPV and Alq3 are the electron-acceptor and donor in the cell, respectively. The respond region matchs the adsorption of Alq3 film. Under UV light with 0.5 mW x cm(-2), the cell shows a short-circuit current of 2.4 microA x cm(-2), open-circuit voltage of 2.6 V, a fill factor of 0.71, and a power conversion efficiency of 0.9%. It was found that the PV cell indicates electroluminescence (EL) performance and could emit orange light at DC voltage. The maximum luminance is about 1 000 cd x cm(-2) at 15 V.


Assuntos
Alumínio/química , Técnicas Eletroquímicas/instrumentação , Polímeros/química , Espectrofotometria/instrumentação , Compostos de Vinila/química , Transporte de Elétrons , Hidroxiquinolinas/química , Luminescência , Estrutura Molecular , Compostos Organometálicos/química , Espectrofotometria Ultravioleta
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