1,720,960 research outputs found
Fitoremediasi Logam Fe dalam Air Asam Tambang Menggunakan Eceng Gondok (Eichhornia Crassipes)
Get PDFKegiatan pertambangan mengakibatkan dampak negatif terhadap lingkungan berupa pencemaran. Salah satu unsur penyebab yaitu air asam tambang (AAT) yang mengandung besi sulfur, seperti pirit (FeS2) dan pirotit (FeS) yang dapat mencemari air permukaan dan air tanah, mengganggu kesehatan masyarakat sekitar Fitoremediasi berupa penggunaan tanaman untuk menghilangkan, memindahkan, menstabilkan atau menghancurkan bahan pencemar baik itu senyawa organik maupun anorganik. Penelitian ini bertujuan untuk menganalisa kandungan logam Fe dalam air asam tambang secara fitoremediasi dengan media eceng gondok. Penelitian dilakukan dengan mengambil sampel air di setlling pond yang tidak aktif pada aliran kompartemen kedua di perusahaan batubara CV. Arjuna dan analisa sampel dilakukan di Laboratorium Budidaya Perairan Fakultas Perikanan dan Ilmu Kelautan Universitas Mulawarman Samarinda. Hasil fitoremediasi menggunakan eceng gondok yang dianalisa menggunakan AAS kandungan logam Fe sebelum fitoremediasi 0,382 mg/l dan sesudah fitoremediasi mengalami penurunan menjadi 0,379 mg/l sampai tidak terdeteksi
PENGARUH LIMBAH CAIR TAMBANG BATUBARA TERHADAP KOMUNITAS MAKROZOOBENTHOS DI SUNGAI KARANG MUMUS
Get PDFLimbah cair pertambangan batubara merupakan limbah yang dapat menimbulkan pencemaran lingkungan, termasuk komunitas makrozoobentos. Penelitian ini bertujuan untuk, mengetahui perbedaan komunitas makrozoobentos di bagian perairan Sungai dan mengetahui pengaruh limbah cair kegiatan pertambangan batubara pada kualitas perairan Sungai. Metode penelitian adalah penelitian kuatitatif dimana komunitas makrozoobentos yang diukur berdasarkan pengambilan sampel di lokasi stasiun-stasiun yang telah ditetapkan dan uji laboratorium. Pengolahan data mengunakan indeks Indeks Keanekaragaman (H'),Indeks Keanekaragaman Shannon – Wiene dan Indeks Dominansi (C). Hasil penelitian menunjukan bahwa limbah cair yang dihasilkan berperan dalam menurunkan kualitas air Sungai, ditandai dengan Indeks Keanekaragaman (H') pada stasiun I rata-rata 1,65 ; stasiun II Indeks Keanekaragaman (H') rata-rata 0; stasiun III Indeks Keanekaragaman (IT) rata-rata 1,08 ; stasiun IV Indeks Keanekaragaman (H') rata-rata 1,6 dan berdasarkan Indeks Keanekaragaman Shannon - Wiener diperoleh informasi bahwa stasiun I dan stasiun IV termasuk kategori perairan tercemar ringan, stasiun III termasuk kategori perairan tercemar sedang, dan stasiun II termasuk kategori perairan tercemar berat, perubahan parameter fisik kimiawi perairan akan mempengaruhi nilai indeks keanekaragaman jenis makrozoobentos dan indeks dominansi. Jenis makrozoobentos, nilai Indeks Dominansi (C) rata-rata pada stasiun II merupakan nilai yang tertinggi yang didapatkan (C = 0,89), karena perairan air sungai sudah mulai terkena limbah pertambangan batubara, dan menyebabkan organisme makrozoobentos yang tidak toleran dengan pencemaran akan berpindah atau mati, sedangkan yang toleran terhadap pencemaran akan bertahan hidup. Jenis yang bertahan adalah kelompok Oligochaeta jenis Lumbriculus sp
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
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
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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