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Study of nanostructured polymeric composites used for organic light emitting diodes and organic solar cells Polymeric nanocomposite films from PEDOT and MEH-PPV embedded with surface modified TiO2 nanoparticles for the hole transport layer and emission layer were prepared, respectively, for organic emitting diodes (OLEDs). The composite of MEH-PPV+nc-TiO2 was used for organic solar cells (OSCs). The characterization of these nanocomposites and devices showed that electrical (I - V characteristics) and spectroscopic (photoluminescent) properties of conjugate polymers were enhanced by the incorporation of nc-TiO2 in the polymers. The organic light emitting diodes made from the nanocomposite films would exhibit a larger photonic efficiency and a longer lasting life. For the organic solar cells made from MEH-PPV+nc-TiO2 composite, a fill factor reached a value of about 0.34. Under illumination by light with a power density of 50 mW/cm2, the photoelectrical conversion efficie...
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Mời các bạn tham khảo tài liệu có chủ đề: "Khảo sát nồng độ tối thiểu ức chế của thuốc Isoniazid trên bệnh nhân lao phổi tại ba bệnh viện" Đề tài: " Khảo sát nồng độ tối thiểu ức chế của thuốc Isoniazid trên bệnh nhân lao phổi tại ba bệnh viện" nghiên cứu nhằm hai mục tiêu: 1- Khảo sát nhân chủng học trên 81 bệnh nhân lao phổi mới và lao phổi tái trị. 2- Khảo sát và so sánh MIC của Isoniazid của 81 bệnh nhân lao phổi mới và lao phổi tái trị... Chi tiết bài viết mời các bạn tham khảo tại đường link: http://repository.vnu.edu.vn/handle/VNU_123/66875?mode=full 
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Retracted Article: Search for time variation of the fine-structure constant using [O III] emission lines This article has been published OnlineFirst, but is withdrawn due to following investigation of complaints received against it. In consultation with the author, both the author and the Editor in Chief Michael Dopita have agreed that substantial portions of the text came from other papers, most notably from Paolo Molaro et al. 2005, Proceedings IAU Symposium No. 232, without attribution, so this clearly constitutes plagiarism. It is clear that the author’s lack of experience in publishing scientific papers led him to make this error. However, whatever the cause, plagiarism in any form cannot be countenanced. The Editor in Chief also notes that the other authors of the paper were unaware of the issue of plagiarism, and that no blame attaches to them... Link: http://repository.vnu.edu.vn/handle/VNU_123/66794?mode=full
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Graphene sheets synthesized by ionic-liquid-assisted electrolysis for application in water purification A facile and green synthesis of graphene sheets by ionic-liquid-assisted electrolysis was investigated in this work. The synthesized graphene sheets have been studied using transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray powder diffraction (XRD), Raman spectroscopy (Raman) and Fourier transform infrared (FTIR) analysis. The obtained graphene was used for the adsorption of Fe2+ whose presence in the drinking water in wide areas of South Asia has been widely known. The result shows that the graphene could absorb Fe2+ with a capacity of 299.3 mg/g which is 6 times higher than that of graphite oxide. The adsorption properties of metal ions on graphene and the effects of variou factors on the adsorption capacity were also investigated in detail. The research results suggest a novel material for developing highly efficient water purification mater...
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The South China Sea security problem: towards regional cooperation The year 2009 marked many dynamic developments in the South China Sea which attracted the attention of the international community. The main objective of this paper is to analyze these recent security developments by examining the following questions: why tensions are rising in the South China Sea, how challenging is the problem, and what can be done to promote regional cooperation among the countries involved? The paper argues that in order to preserve regional stability, a comprehensive approach must be developed, beginning with confidencebuilding measures through cooperation in solving non-traditional security problems... Link: http://repository.vnu.edu.vn/handle/VNU_123/66783?mode=full
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 Trung tâm thông tin thư viện, Đại học Quốc gia Hà Nội xin trân trọng gửi tới Quý bạn đọc bài viết với chủ đề: " Sự gắn kết của người lao động với doanh nghiệp" Trên cơ sở nghiên cứu lý luận và thực tiễn về sắn kết tổ chức của người lao động, đề tài làm rõ những nguyên nhân ảnh hưởng đến thực trạng này và tác động của nó, đồng thời đề xuất một số kiến nghị nâng cao sắn kết tổ chức của người lao động... Chi tiết bài viết mời các bạn tham khảo tại đường link: http://repository.vnu.edu.vn/handle/VNU_123/63468?mode=full
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Explicit secular equations of Stoneley waves in a non-homogeneous orthotropic elastic medium under the influence of gravity The problem of Stoneley waves in a non-homogeneous orthotropic elastic medium under the influence of gravity was studied recently by Abd-Alla and Ahmed [A.M. Abd-Alla, S.M. Ahmed, Stoneley waves and Rayleigh waves in a non-homogeneous orthotropic elastic medium under the influence of gravity, Appl. Math. Comput. 135 (2003) 187–200], who derived the secular equation of the wave in the implicit form. In this paper, by using an appropriate representation of the solution, we obtain the secular equation of the wave in the explicit form. Moreover, considering its special cases, we derive explicit secular equations for a number of investigations of Stoneley waves under the influence of gravity, for which only the implicit dispersion equations were previously obtained. Link: http://repository.vnu.edu.vn/handle/VNU_123/66738?mode=full
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