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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Karakterisasi variasi temperatur pembentukan fase lithium ferro phosphate sebagai bahan komposit LFP/C melalui proses padat
Get PDFLithium Ferro Phosphate Carbon Composite (LFP/C) telah berhasil
disintesis dengan metode solid state menggunakan high energy ball milling.
Pembentukan LFP/C menggunakan sumber elemen Fe yang berasal dari pasir besi
alam magnetit Fe3O4. Batu besi magnetite Fe3O4 dari Tanah Laut Kalimantan
memiliki kandunga elemen Fe mencapai 98% setelah pencucian dengan ultrasonic
cleaner. Asam sitrat dipilih sebagai sumber carbon pembentukan komposit LFP/C
karena dapat mencegah terjadinya oksidasi Fe2+ menjadi Fe3+. Semua bahan
Li2CO3, (NH4)2HPO4, Fe3O4, dan asam sitrat di milling menjadi 1 dengan
perbandingan 3:6:2 mol dan asam sitrat 5%wt. Pengujian awal DSC-TGA untuk
mengetahui sifat termal dari precursor LFP/C dan menentukan variasi temperatur
kalsinasi terkait dengan proses pembentukan fase LFP/C. Variasi temperatur
dilakukan pada 300, 400, 500, 600, dan 700°C. Analisis pola difraksi sampel
menunjukkan bahwa fase LFP/C mulai terbentuk pada temperatur 400°C. Fasefase
yang terbentuk pada variasi temperatur kalsinasi antara lain diphosphate
LiFeP2O7 pada temperatur rendah dan Nasicon Li3Fe2(PO4)3 pada temperatur yang
lebih tinggi. Selain itu muncul fase impuritas Maghemit dan Hematite Fe2O3.
Pengujian dengan PSA menunjukkan bahwa semakin tinggi temperatur maka
ukuran partikel juga semakin besar. Gugus-gugus phosphat yang menunjukkan
terbentukkan ikatan antar atom dalam senyawa pospat sampel LFP/C terlihat
dengan munculnya puncak absorbansi yang intens pada rentang panjang
gelombang 900-1300 cm-1. Cyclic Voltametry (CV), Charge/Discharge (C/D)
Capacity, dan Electrochemical Impedance Spectroscopy (EIS) dilakukan untuk
melihat performa dari material katode LFP/C. Kapasitas muatan yang paling baik
didapatkan pada sampel yang dikalsinansi pada 500°C LFP/C-5 yakni sebesar
14,3 mAh/g ketika didischarge dengan arus 25μA, dan 6,17 mAh/g ketika di
discharge dengan arus beban yang lebih besar yakni 50μA. Komposisi fase yang
terbentuk pada temperatur 500°C memiliki %molar fase LFP yang paling besar
yakni adalah diphosphate 58,88% LiFeP2O7 dan 23,78% nasicon Li3Fe2(PO4)3.
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Lithium Ferro Phosphate Carbon Composite LFP/C has been synthesized
by using high energy ball milling solid state method. Magnetite iron sand Fe3O4
from Tanah Laut Kalimantan has been purified using ultrasonic cleaner contain
98% Fe element. Then it was used as Fe source to make LFP/C. Citric acid was
chosen as carbon source because it can avoid the oxidation Fe2+to be Fe3+. All of
these materials, Li2CO3, (NH4)2HPO4, Fe3O4 and citric acid were milled together
with 3:6:2 mole comparison and 5%wt citric acid. Thermal properties of LFP
precursor was identified by using DSC-TGA to determine calcination temperature
of LFP formation. Temperature was varied at 300, 400, 500, 600 and 700°C to
know the phases formed in each temperature. Based on diffraction analysis of
sample that has been calcined at 400°C the LFP/C phase formed is diphosphate
LiFeP2O7. In the higher temperature 500, 600, and 700°C the diphosphate phase
gradually vanish and transform to Nasicon Li3Fe2(PO4)3. The others are
impurities phases, maghemite and hematite Fe2O3. Identification particle size
using PSA show that as the temperature getting higher the particle size is getting
higher too. Structural and lattice dynamic characteristics of phosphate based
compound was observed by high intense absorbance spectra in range 900-1300
cm-1. Cyclic Voltametry (CV), and Charge/Discharge (C/D) Capacity, and
Electrochemical Impedance Spectroscopy (EIS) test are conduct to know the
LFP/C batteries perform. The LFP/C-5, sample calcined at 500° has the highest
specific capacity, 14,3 mAh/g when 25μA discharge current applied, and 6,17
mAh/g when 50μA discharge current. The phase composition of the sample
calcined at 500°C has the highest %molar of LFP phase, 58,82%molar
diphosphate phase and 23,78%molar nasicon phase with % weight composition
consist of 33,44%wt diphosphate and 46,54%wt nasicon phase. The carbon
containing in composite LFP/C are detected by EDX test
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Analisis Struktur Kristal Silika (SiO₂) Pasir Pantai Dogolan Menggunakan Metode Rietveld
Get PDFPenelitian ini merupakan penelitian awal mengenai konversi pasir pantai Dogolan menjadi mineral bernilai tinggi untuk meningkatkan nilai ekonomisnya. Sebab, selama ini pemanfaatannya terbatas pada penggunaan pribadi warga lokal sebagai bahan bangunan yang nilai ekonominya rendah. Sehingga tujuan dari penelitian awal ini adalah untuk mengetahui jenis kandungan silika dan struktur fasanya. Salah satu cara yang dapat digunakan untuk menganalisis permasalahan ini adalah dengan metode Rietveld. Metode uji karakterisasi strukturnya dilakukan dengan uji Difraksi Sinar-X (XRD) menggunakan alat XRD X’Pert PRO PANalytical pada 2θ= 15-65⁰. Sedangkan analisis secara kualitatifnya menggunakan software Match! dan analisis kuantitatifnya dengan perangkat lunak Rietica yang merupakan implementasi dari metode Rietveld. Hasil pola difraktogram XRD menunjukkan bahwa material pasir Pantai Dogolan merupakan fasa kristalin dengan kandungan mineral utamanya adalah silika SiO₂ kuarsa. Hal ini dibuktikan dengan adanya 2 puncak difraksi utama yang tinggi dan tegas pada posisi 2θ= 20,86 dan 26,51. Hasil analisis kualitatif dari Software Match! Menunjukkan adanya fasa quartz low dengan presentase 100% dan sesuai dengan databased PDF. Hasil identifikasi dan analisis lanjut, sampel pasir Pantai Dogolan tergolong fasa alpha quartz dengan sistem Kristal trigonal. Analisis kuantitatif dengan perangkat lunak Rietica menunjukkan pembentukan fasa tunggak SiO₂ yang dibuktikan dengan nilai kecocokanyang dapat diterima telah terpenui. Berdasarkan hasil penelitian yang telah dilakukan, pasir pantai Dogolan memiliki kandungan Silika Kuarsa SiO2, diharapkan ke depan mempunyai potensi lanjut untuk dijadikan penerapan material berteknologi tinggi dan dapat meningkatkan nilai ekonomisnya
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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