scholarly journals Preliminary Study on Gold Recovery from High Grade E-Waste by Thiourea Leaching and Electrowinning

Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 235
Author(s):  
Nicolò Maria Ippolito ◽  
Ionela Birloaga ◽  
Francesco Ferella ◽  
Marcello Centofanti ◽  
Francesco Vegliò

The present paper is focused on the extraction of gold from high-grade e-waste, i.e., spent electronic connectors and plates, by leaching and electrowinning. These connectors are usually made up of an alloy covered by a layer of gold; sometimes, in some of them, a plastic part is also present. The applied leaching system consisted of an acid solution of diluted sulfuric acid (0.2 mol/L) with thiourea (20 g/L) as a reagent and ferric sulfate (21.8 g/L) as an oxidant. This system was applied on three different high-grade e-waste, namely: (1) Connectors with the partial gold-plated surface (Au concentration—1139 mg/kg); (2) different types of connectors with some of which with completely gold-plated surface (Au concentration—590 mg/kg); and (3) connectors and plates with the completely gold-plated surface (Au concentration—7900 mg/kg). Gold dissolution yields of 52, 94, and 49% were achieved from the first, second, and third samples, respectively. About 95% of Au recovery was achieved after 1.5 h of electrowinning at a current efficiency of only 4.06% and current consumption of 3.02 kWh/kg of Au from the leach solution of the third sample.

2013 ◽  
Vol 54 (3) ◽  
pp. 289-299
Author(s):  
Jürgen Hunkemöller

The recognition of topoi, i.e. traditional formulae, is an important means of musical analysis. To illustrate this, the paper discusses the types of the battaglia and the pastoral in Bach’s Cantata Halt im Gedächtnis Jesum Christ, and briefly enumerates different types of allusions to jazz in 20th-century compositions by Stravinsky, Milhaud, Blacher, Tippet, and Zimmermann. Then it raises the possibility of an analysis of topoi in Bartók’s music in four main categories. It considers Bartók’s musical quotations from Bach to Shostakovich; the chorale as special topos appearing in Mikrokosmos, in the Concerto for Orchestra, in the Adagio religioso of the Third Piano Concerto; the topos-like employment of the tritone; and finally the idea of a Bartókian Arcadia in the Finale of Music for Strings, and the integration of bird song in the Adagio religioso.


2014 ◽  
Vol 1 (1) ◽  
Author(s):  
Colby Doyle ◽  
Matthew Gaudet ◽  
Dominic Lay ◽  
Amber McLeod ◽  
Robert Schaeffer

The primary goal of this research is to identify and examine the components of responsible drinking advertisements. We will examine industry and government related advertisements as we try to understand one of our major questions: does the source influence the validity of the message? The next group of major questions that we will be looking to answer is how are the vague quantifiers used in responsible drinking campaigns interpreted by the public?  How many drinks do people consider “too much?” What does “drink responsibly” really mean? The third major question is whether or not an individual’s current consumption patterns of alcohol have any effect on how individuals assess responsible drinking campaigns. Our qualitative research has indicated that social influences can be strongly related with drinking patterns; this will be further examined in our quantitative research. Also, we will be looking into some of the psychology behind industry and government sponsored advertisements as well as gathering and interpreting information from a sample of our target demographic. Our target demographic consists of both male and females between the ages 18-24. Our literature review and qualitative analysis gave us good insight into some of the potential answers to our questions. We will use these potential answers from our previous research to guide us as we attempt to conduct conclusive research based on a sample data of 169 individuals. Our findings will aid us in developing conclusions and recommendations for Alberta Health Services.


Author(s):  
Vijay Pillai ◽  
Harley Heinrich ◽  
David Dieska ◽  
Pavel V. Nikitin ◽  
Rene Martinez ◽  
...  

Author(s):  
Saeema Ahmed ◽  
Luciënne Blessing ◽  
Ken Wallace

Abstract The aerospace industry, along with other industries, has acknowledged the need to bridge the experience gap between novice and experienced designers [Moore, 1997]. The research aims to identify the support a novice designer requires to gain experience faster. The focus of this paper is to present some initial results of a study of novice and experienced designers. This initial study highlighted the difficulty in establishing consistent and precise usage for the terms data, information and knowledge. It is concluded that data, information and knowledge are relative concepts that cannot be defined in absolute terms. As relative concepts, these help differentiate experts and novices, and different types of novices. The relationships between data, information and knowledge are examined with the aim of prompting a discussion.


2013 ◽  
Vol 3 (3) ◽  
pp. 1-66
Author(s):  
Inge Pasteels ◽  
Dimitri Mortelmans

In deze bijdrage wordt het herpartneren na een scheiding uit een eerste huwelijk beschreven. Met gegevens van “Scheiding in Vlaanderen” verzameld bij 1192 mannen en 1448 vrouwen gescheiden tussen 1981 en 2005, wordt vooreerst de timing van het herpartneren alsook de leefvorm waarvoor men kiest in postmaritale relaties, bestudeerd. We onderscheiden LAT‐relaties, ongehuwd samenwoonrelaties en tweede huwelijken. Daarna wordt de huidige partnerstatus van gescheidenen anno 2010 in kaart gebracht. Ten derde komt de mate waarin partners uit eerste huwelijken of postmaritale relaties gelijkend zijn aan bod. Vervolgens wordt de stabiliteit van LAT‐relaties of ongehuwde samenwoonrelaties na een eerste huwelijk bestudeerd. Een beschrijving van postmaritale relatietrajecten met aandacht voor relatierang en relatietype rondt deze bijdrage af. Alle analyses worden apart uitgevoerd voor mannen en vrouwen van verschillende scheidingscohorten. Abstract : Using surveydata of “Divorce in Flanders” for 1192 men and 1448 women, divorced between 1981 and 2005, we explore repartnering after a first divorce. Firstly, prevalence and timing of repartnering are examined. LAT‐relationships, unmarried cohabitation and remarriage are considered as different types of repartnering. Secondly, the current partner status for divorcees in 2010 is described. Homogamy in first marriages and in higher order relationships is the third topic in this article. At last, stability of postmarital relationships and partnership trajectories are explored. Data are analyzed using a cohort perspective and a gender perspective.


2017 ◽  
Vol 141 (10) ◽  
pp. 1313-1315 ◽  
Author(s):  
Reena Singh ◽  
Kathleen R. Cho

Context.— Nonuterine high-grade serous carcinomas (HGSCs) are believed to arise most often from precursors in the fallopian tube referred to as serous tubal intraepithelial carcinomas (STICs). A designation of tubal origin has been suggested for all cases of nonuterine HGSC if a STIC is identified. Objective.— To highlight that many different types of nongynecologic and gynecologic carcinomas, including HGSC, can metastasize to the tubal mucosa and mimic de novo STIC. Data Sources.— A mini-review of several recently published studies that collectively examine STIC-like lesions of the fallopian tube. Conclusions.— The fallopian tube mucosa can be a site of metastasis from carcinomas arising elsewhere, and pathologists should exercise caution in diagnosing STIC without first considering the possibility of metastasis. Routinely used immunohistochemical stains can often be used to determine if a STIC-like lesion is tubal or nongynecologic in origin. In the context of uterine and nonuterine HGSC, STIC may represent a metastasis rather than the site of origin, particularly when widespread disease is present.


2007 ◽  
Vol 1 (1) ◽  
pp. 74-80 ◽  
Author(s):  
Marcia Dourado ◽  
Valeska Marinho ◽  
Cláudia Soares ◽  
Eliasz Engelhardt ◽  
Jerson Laks

Abstract Objective: To describe the development of the Assessment Scale of Psychosocial Impact of the Diagnosis of Dementia (ASPIDD), a multidimensional scale to evaluate awareness of disease in dementia. Method: The development of this scale was conducted in four steps. In step one, questions were drawn up after a review of the literature. The second step involved the suggestions offered by a neurologist regarding the skills considered important for the scale. The third step involved the re-writing and review of the domains and questions in the scale followed by a semantic evaluation performed by two independent psychiatrists. Step four consisted of the preliminary study aimed at evaluating the applicability of the ASPIDD. Results: In the semantic evaluation only minor changes were proposed. The preliminary sample had 52 patients, comprising 23 CDR 1 (male=9; female=14) and 29 CDR2 (male=13; female=16). Mean age of patients was 69.7±5.51 (CDR1) and 73.6±9.4 (CDR2), and age at onset was 66.4±5.7 years (CDR1) and 68.3±9.3 year (CDR2). Mean schooling was 9.0±4.3 years (CDR1) and 8.8±4.4 years (CDR2). Mean MMSE was 21.0±3.3 (CDR1) and 17.6±3.5 (CDR2). Mean Cornell was 4.8±2.3 (CDR1) and 4.2±1.9 (CDR2). The patient and caregiver dyads were aware of problems, mainly of those related to social, family and affective relations. The higher rates of discrepant responses were found on the awareness of cognitive deficits and changes in ADL. Conclusion: The ASPIDD is a multidimensional instrument to assess awareness of disease among AD patients.


Author(s):  
Burcu Taylan ◽  
Sule Gurkan ◽  
Ertan Taskavak ◽  
Arzu Aydın Uncumusaoglu

In this research, a preliminary study was carried out in January and February 2014 to determine the fecundity of the whiting species in Tirebolu, Eastern Black Sea. After the total length (cm) and weight (0.01 g) of the 70 fish specimens were measured in the laboratory, they were dissected for sex determination. Using the 20 ovaries at the third and fourth maturation stages, 3 sub-samples which is 2-5% of the total ovary weight (from the anterior, median and posterior parts of the ovary) were taken from each ovary to determine the fecundity, and hydrated oocytes were counted with gravimetric method. Total fecundity, total oocytes number in the ovary were computed with the formula F=(n×G)/g. The total length-weight values were 12.6-23.3 cm (mean 17.08±2.12) and 15.59-95.72 g (mean 41.07 ± 16.75), respectively, and total length-weight relationship was computed as W=0.0073L3.024 (R2=0.94) for the 70 fishes evaluated. Fecundity was computed as 3.247-30.534 (mean: 10.139±6.953) eggs and a linear relationship between fecundity and total length was calculated as F=0.0186L4.5631 (R2=0.70). In conclusion, the fecundity results of this prelaminar study were compared with similar studies on the whiting species from Black Sea and other seas.


2021 ◽  
Vol 21 (86) ◽  
pp. e237-e243
Author(s):  
Kaan Orhan ◽  
◽  
Poyzan Bozkurt ◽  
Zeynep Serap Berktaş ◽  
Mehmet Hakan Kurt ◽  
...  

Aim of the study: The present preliminary study aims to evaluate the possible positive outcomes of ultrasonography-guided sialolithotomies and duct stricture dilations utilizing stone retrieval baskets and guide wires. Case description: A total of 6 cases in an ongoing study (4 cases of sialolithiasis and 2 cases of duct strictures with intraluminal adhesion) were analyzed. All sialoliths were <5 mm in diameter. Stone removals and duct dilations were performed under ultrasonography guidance with two different types of linear probes. Edema measurements were carried out, and the area of edema was evaluated via the echogenicity changes. Patient satisfaction was also evaluated by the patients themselves using a Visual Analog Scale questionnaire on postoperative day 0, and on days 1, 2, and 3. Conclusions: There were no postoperative complications, and mouth openings returned to normal at 7-day follow-up. The pain scores decreased after 6 hours, and pain subsided completely after 12 hours in all the patients. Edema also resolved gradually after the operation. The patient satisfaction levels were high.


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