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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
بررسی قابلیت بیومس آزولا و عدسک در جذب پی-کرزول از محیطهای آبی: بررسی ایزوترم و سینتیکهای جذب
No full textBackground and Aims: Cresol is an extremely toxic phenolic compound even at low concentrations which can be found in industrial effluents. The aim of this study was, therefore, to assess the ability of modified Azolla and Lemna minor in p-cresol removal from aqueous solution.Materials and Methods: In the present empirical-bench scale study, we activated the Azolla and Lemna minor by 0.1M HCl and dried in the oven at 105 °C for 24 h. The effects of contact time, pH, initial cresol concentration and biomass amount on adsorption performance were investigated. Adsorption isotherms and kenitics were then used to explain the gathered experimental data. The concentration of p-cresol wasmeasured by UV-VIS spectrophotometer at 280 nm.Results: The results indicated that although the efficiency of p-cresol removal increased by increasing both contact time and the amount of bioadsorbent, the adsorption capacities [qe], however, decreased either in the case of Azolla or Lemna minor. The adsorption capacity also decreased by increasing initial p-cresol concentration. The optimum pH of p-cresol removal was 3. The adsorption process followed the Langmuir isotherm and pseudo-second-order kinetic.Conclusion: According to our results, Azolla and Lemna minor can be used as effective and affordable adsorbents for the removal of phenolic compounds from industrial effluents.
چكيده
زمينه و هدف: پی-کرزول یکی از ترکیبات فنل مییاشد که حتی در غلظتهای بسیار کم بشدت سمی میباشد و در فاضلابهای صنعتی یافت میشود. هدف از این تحقیق بررسی مقایسهای حذف پیکرزول توسط جاذبهای گیاهی آزولا و عدسک میباشد.
مواد و روشها: این تحقیق یک نوع مطالعه تجربی- آزمایشگاهی بود. گیاه عدسک و آزولا با استفاده از هیدروکلریک اسید 1/0 مولار فعالسازی شد و در فور در دمای 105 درجه در مدت 24 ساعت خشک گردید. تاثیر پارامترهای مختلف مثل زمان تماس، pH، غلظت اولیه کرزول، مقدار جاذب بر عملکرد جاذب بررسی شد و ایزوترمها و سنتیکهای جذب تعیین گردید. غلظت پیکرزول به روش UV در طول موج 280 نانومتر اندازهگیری شد.
يافتهها: نتایج نشان داد با افزایش زمان تماس و مقدار جاذب میزان حذف پیکرزول در هر دو جاذب افزایش مییابد ولی ظرفیت جذب [qe] کاهش مییابد. همچنین با کاهش غلظت اولیه پیکرزول، میزان حذف افزایش یافت و بهترین pH برای حذف پیکرزول برابر با 3 بدست آمد. بهترین نوع ایزوترم و سینتیک واکنش، برای جاذبها لانگمیر و سینتیک درجه 2 بود.
نتيجه گيري: با توجه به نتایج بدست آمده گیاه عدسک و آزولا میتوانند بعنوان جاذبهای موثر و ارزان و در دسترس برای حذف ترکیبات فنلی از پساب مورد استفاده قرار گیرند.
 
جذب 2 کلروفنل توسط کربن فعال حاصل از پوست پرتقال و پوست موز: مطالعات تعادلي و سينتيکي
Get PDFBackground and Objectives:Phenolic compounds present in many industrial effluents that classified as priority pollutants. Therefore, its treatment is necessary before discharge into the environment. The aim of this study was to assess the 2-chlorophenol adsorption by orange and banana shell activated carbon.
Materials and Methods:This study was performed in laboratory at batch scale. The orange and banana peel was sun dried at 105 Cº, then carbonized, crushed and sieved to particle sizes in range of 30 mesh. The effects of different parameters including contact time (10-120 min), pH (3-11), 2-chlorophenol initial concentration(10-200 mg/L) and biomass dosage (0.2-2 g/L) were studied for removal of 2-chlorophenol. All experiments were repeated twice and then adsorption isotherms and kinetics of different models were analyzed by comparing the regression coefficient and R-squared (R2).
Results: The results indicated that the 2-chlorophenol adsorption rate increases by increasing of contact time and adsorbent dose for both adsorbents, however, the 2-chlorophenol adsorption per each gr of adsorbnts(qe) decreased. The adsorption efficieny increased by decreasing of intial 2-chlorophenol concentration and increasing of pH. The optimum pH was 5 in 2-chlorophenol adsorption and obtained data well fitted by Langmuir Isotherm in comparison with other isotherms. It was found that the kinetics data fitted well the pseudo-first order.
Conclusion: According to the achieved results, it can be concluded that orange and banana shell activated carbon as an inexpensive adsorbent, had a high adsorptive potential for removal of 2-chlorophenol from water and wastewater samples.
How to cite this article: Zazouli MA, Balarak D. Adsorption of 2-Chlorophenol on Activated Carbon Prepared from Orange and Banana Husk: Equilibrium and Kinetic Studies.Irtiqa Imini Pishgiri Masdumiyat (Safety Promotion and Injury Prevention). 2016; 4(2):117-128.
سابقه و هدف:ترکیبات فنلی در فاضلاب صنایع مختلف موجود بوده و جزء آلایندههای دارای تقدم میباشند، بنابراین قبل از تخلیه به محیطزیست باید مورد تصفیه قرار گیرند. هدف مطالعه حاضر، بررسی جذب 2-کلروفنل توسط کربن فعال حاصل از پوست پرتقال و پوست موز بود.
روش بررسی: این تحقیق بهصورت آزمایشگاهی و بهصورت ناپیوسته انجام گرفت. پوست پرتقال و موز در دمای 105 درجه سانتیگراد خشک و سپس کربونیزه و در اندازه 30 مش دانهبندی شد. تأثیر پارامترهای مختلف مثل زمان تماس (10تا 120 دقیقه)، (11-3) PH غلظت اولیه 2-کلروفنل (10 تا 200 میلیگرم در لیتر) و دوز بیومس (0/2 تا 2 گرم در لیتر) بر عملکرد جاذب بررسی شد. نمونهها با دو بار تکرار مورد آزمون قرار گرفتند و مدلهای مختلف ایزوترم و سرعت واکنش جذب از طریق مقایسه ضریب رگرسیون (R2) تحلیل شد.
یافتهها: نتایج نشان داد با افزایش زمان تماس و دوز جاذب، میزان حذف 2 کلروفنل با هر دو جاذب افزایش مییابد، اما ظرفیت جذب جاذب (qe) کاهش مییابد. با کاهش غلظت اولیه 2 کلروفنل، میزان حذف افزایش یافت و pH بهینه برای جذب معادل 5 تعیین گردید. دادههای حاصل از ایزوترم جذب لانگمویر برای هر دو جاذب بهتر از سایر ایزوترمها پیروی میکنند. از طرف دیگر بررسی سینتیک جذب بیانگر تطابق بهتر دادهها با معادله درجهدوم کاذب بود.
نتیجهگیری: بر اساس نتایج حاصل از مطالعه حاضر مشخص شد که کربن فعال حاصل از پوست پرتقال و موز بهعنوان یک جاذب ارزانقیمت از پتانسیل جذب بالایی در حذف آلاینده 2-کلروفنل از نمونههای آب و فاضلاب برخوردار میباشد.
How to cite this article:
Zazouli MA, Balarak D. Adsorption of 2-Chlorophenol on Activated Carbon Prepared from Orange and Banana Husk: Equilibrium and Kinetic Studies. J Saf Promot Inj Prev. 2016; 4(2):117-28.
 
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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