The new Coronavirus (namely Covid-19) discovered in 2019 in Wuhan has sickened more than three million people in worldwide. Because Covid-19 is spreading so fast and killing so many people, it has encouraged researchers to conduct research and publish it in various mass media, including journals. This study aims to analyze the scope of Covid-19 research using a bibliometric review. To obtain information about Covid-19 studies, the Scopus database was used. Topic areas with titles, keywords, and abstract criteria in Covid-19 studies were used as a reference for extracting search results. Search result extraction was done using VOSviewer. After that, the results of bibliometric mapping were analyzed further. A total of 3,513 articles were found in the Scopus database accessed on April 25, 2020. There was a significant increase in the number of publications on Covid-19 from 2019 to 2020. Among all countries, China contributed the most publications. Meanwhile, the keywords coronavirus, pandemic, and impact turned out to be the area's most widely discussed. Through VOSViewer we analyzed how many articles have been published about Covid-19 and its relationships to a topic area. This review certainly can provide a reference point for further research related to the Covid-19 outbreak.
Di era globalisasi seperti sekarang ini, manusia dituntut untuk selalu mengikuti perkembangn teknologi yang begitu pesat terutama dengan hadirnya internet ke dalam segala segi aspek kehidupan manusia. Selain itu teknologi informasi juga memberikan peranan yang besar dalam pengembangan keilmuan dan menjadi sarana utama dalam suatu institusi akademik. Secara garis besar, teknologi informasi memiliki peranan : (1) dapat menggantikan peran manusia; (2) memperkuat peran manusia; (3) berperan dalam restrukturissi terhadap peran manusia. Kehadiran internet dalam dimensi pendidikan merupakan suatu hal yang mutlak, dan sudah merupakan kebutuhan. Kehadiran internet pada dasarnya sangat membantu dunia pendidikan untuk mengembangkan situasi belajar mengajar yang lebih kondusif dan interaktif. Penggunaan internet yang berisi segala konten menuntut penggunanya untuk bijak menyikapinya terutama terhadap hal-hal yang negatif sehingga peran orang tua dan guru untuk melakukan pendampingan sangat diperlukan agar peserta didik tidak terjerumus kepada hal-hal yang negatif sebagai dampak penggunaan internet.
The present study deals with the synthesis and characterization of ZrO 2 nanomaterial which can be used as an adsorbent for Molybdenum-99 ( 99 Mo).The adsorbent can potentially be utilized as the material for 99 Mo/ 99m Tc generator column. Using the sol-gel method, monoclinic nanocrystalline zirconia was synthesized from zirconium oxychloride in isopropyl alcohol reacted with ammonium hydroxide solution in isopropyl alcohol resulting in a white gel. The gel was subsequently refluxed for 12 hours at ~95 °C and pH at ~4 and then dried at 100 °C. The drying gel was then calcined at 600 °C for two hours. Meanwhile the orthorhombic nanocrystalline zirconia was obtained by reacting zirconium oxychloride solution with 2.5 M ammonium hydroxide solution which resulted in a white gel. The gel was then refluxed for 24 hours at ~95 °C and pH at ~11 and then dried at 100 °C. The drying gel was then calcined at 600 °C for two hours. These materials were characterized using FT-IR spectroscopy, X-ray diffraction (XRD), and Transmission Electron Microscope (TEM). The Scherrer method is used for determination of crystallite size. The FT-IR spectra for both materials show absorption peak at 450-500 cm -1 which are attributed to Zr-O bond. The XRD pattern of monoclinic nanocrystalline form shows crystalline peaks at 2θ regions of 28.37 °, 31.65 °, 34 °, 36 ° and 50.3 ° with average crystallite size of 2.68 nm. Meanwhile, the XRD pattern of orthorhombic nanocrystalline form shows crystalline peaks at 2θ regions of 30 °, 35 °, 50 ° and 60 ° with average crystallite size of 0.98 nm. The TEM micrograph indicates that the zirconia nanomaterials prepared were quite uniform in size and shape.
SIMULATIONS ON NICKEL TARGET PREPARATION AND SEPARATION.OF Ni(II)-Cu(II) MATRIX FORPRODUCTION OF RADIOISOTOPE64Cu64Ni (p,n) 64 and retained on the column while the nickel was kept in the form of Ni2+ 2+ 2+ and CuCl while the nickel was totally in the form of Ni2+ while the nickel was found as both Ni2+ and NiCl while the nickel was mostly in the form of Ni2+. The retained CuCl was then changed back into Cu2+ Keywords 64 Cu, Anion exchange chromatography.: Nickel target preparation, Radioisotope Cu-64, Separation of Ni(II)-Cu(II) matrix, Nuclear reaction of 64Ni(p,n) cation form andeluted out the column by using HCl 0.05 M. The 42– 4 2–.The best condition of separation was in HCl 8 M in which the radioactive copper was mostly in the form of CuCl 42– 42– . In the condition ofHCl 9 M, the radioactive copper was mostly in the form of CuCl 42– cation. It was found that the electroplating result from the acidic solution was more satisfied than that from the basic solution. By conditioning the matrix solution at HCl 6 M, the radioactivecopper was found in the forms of Cucation and eluted off from the column. The retained radioactive copper was then eluted out the column in the condition of dilute HCl changingback the copper anion complex into Cu42– Cu. The nickel target preparation was performed by means of electroplating method using acidic solution of nickel chloride - boric acid mixture and basic solution of nickel sulphate – nickel chloridemixture on a silver- surfaced-target holder. The simulated solution of Ni(II) – Cu(II) matrix was considered as thesolution of post-proton-irradiated nickel target containing both irradiated nickel and radioactive copper, but in thepresented work the proton irradiation of nickel target was omitted, while the radioactive copper was originallyobtained from neutron irradiation of CuO target. The separation of radioactive copper from the nickel target matrixwas based on anion exchange column chromatography in which the radiocopper was conditioned to form anioncomplex CuClg-spectrometric analysis showed a single strong peak at 511 keVwhich is in accord to g-annihilation peak coming from positron decay of Cu-64, and a very weak peak at 1346 keVwhich is in accord to g-ray of Cu-64.. The simulations on Nickel target preparation and separation of Ni(II)- Cu(II) matrix has been carried out as a preliminary study for production of medical radioisotope Cu-64 based onnuclear reaction of
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