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    Pore structure and graphitic surface nature of ordered mesoporous carbons probed by low-pressure nitrogen adsorption

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    Ordered mesoporous carbons (OMCs) were produced by pyrolysis of sucrose adsorbed in two different silica matrices (MCM-48 and SBA-15), followed by dissolution of the matrix in hydrofluoric acid. Subsequently, some of these OMCs were heat-treated at temperatures of up to 1600 degreesC. The ONIC pore structure was studied by low-pressure nitrogen adsorption. Information on the graphitic order of the surface of the mesopore walls was also obtained from the nitrogen adsorption data. These results were correlated to the order of the graphene layers at the outer surface, which was studied by X-ray photoelectron spectroscopy (XPS). The OMCs were predominantly mesoporous, but they also contained micropores. For OMCs produced in an SBA- 15 matrix, the micropore volume decreased upon heating. After heating to 1600 degreesC, nearly all micropores had disappeared. Furthermore, upon heating the width of the mesopores increased from 35 to 50 Angstrom. All these changes can be explained by a shrinking of the OMC framework upon heating. A different behavior was found for OMCs derived from MCM-48. Upon heating these materials at increasingly high temperatures, the width of the mesopores first decreased, and for temperatures above 1100 degreesC it increased again. For all OMCs studied the graphitic order of the mesopores and the order of the graphene layers at the outer surface increased upon heating. For a given temperature, the graphitic surface order of OMCs derived from SBA-15 and MCM-48 was similar. (C) 2003 Elsevier Science Inc. All rights reserved.The authors are thankful to Dr. Annette Schwerdtfeger for reviewing the manuscript. R. Ryoo gratefully acknowledges that this work was supported in part by the Korean Ministry of Science and Technology through the Creative Research Initiative Program, and by the School of Molecular Science through the Brain Korea 21 Project

    Wellesly Sh. W. to Mr. James Meredith (2 October 1962)

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    Signed by Wellesly Sh. W.https://egrove.olemiss.edu/mercorr_pro/1531/thumbnail.jp

    PENERAPAN PROTOKOL KESEHATAN COVID-19 DI KANTOR PPAT ROY INDARTO, SE, SH, MKn BERDASARKAN PERATURAN BUPATI NOMOR 60 TAHUN 2020

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    Dalam upaya penenggulangan Pandemi COVID-19 pemerintah memberlakukan darurat kesehatan dengan menyelengarakan karantina kesehatan sebagai mana telah diatur dalam undang-undang Nomor 6 tahun 2018 tentang kekarantinaan kesehatan. Penyebaran COVID-19 saat ini telah semakin meningkat dan menyebar keseluruh wilayah dan lintas negara, yang diiringi tingkat kasus dan/atau jumlah kematian yang sangat tinggi.yang berdampak pada sektor pendidikan,ekonomi,keagamaan, serta fasilitas umum yang disediakan oleh pemerintah, sehingga diperlukan percepatan dalam menangani COVID-19 yang dilakukan dalam bentuk tindakan Pembatasan Sosial Bersekala Besar (PSBB), dalam rangka menekan penyebaran COVID-19 termasuk pembatasan terhadap pergerakan orang dan/atau barang untuk satu Provinsi atau Kebupaten/Kota  tertentu untuk mencegah COVID-19. Tulisan ini dibuat untuk mengkaji bagaimana penerapan Protokol Kesehatan sesuai dengan pasal (Pasal 6 Perbub Nomor 60 Tahun 2020) di dalam rung lingkup kantor PPAT ROY INDARTO, SE,SH,Mkn
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