scholarly journals Studying the impact of alkaline sulfide leaching parameters upon the efficiency of arsenic recovery from copper skimmings of lead production

2020 ◽  
pp. 19-24
Author(s):  
A. A. Tymbayeva ◽  
S. V. Mamyachenkov ◽  
S. A. Bannikova ◽  
O. S. Anisimova
Keyword(s):  
Elemental Sulfur ◽  
Arsenic Removal ◽  
Waste Product ◽  
Precious Metals ◽  
Advantages And Disadvantages ◽  
Lead Production ◽  
Solids Content ◽  
Leaching Parameters ◽  
The Impact ◽  
Alkaline Sulfide

The article is concerned with the problem of arsenic circulation as copper skimmings of lead production — the product of the lead bullion decopperization process at a metallurgical complex, uniting copper and lead plants. A brief overview of the methods of processing arsenic-containing middling products for the purpose of arsenic removal is given; the main advantages and disadvantages are indicated. The possibility of processing copper skimmings by the method of alkaline sulfide leaching with separation into arseniccontaining solution and lead-copper precipitate is studied. The results of the researches into the influence of temperature, process duration, solids content in the pulp, particle size, and the ratio of sodium hydroxide to elemental sulfur in the alkaline sulfide reagent on the process of alkaline sulfide leaching of copper skimmings af lead production are provided. Within the studied range of varied factors, the highest indexes of arsenic extraction into solution (85.04%) were achieved under the following conditions: temperature — 85 °C, duration — 4 hours, solids content in the pulp — 350 g/dm3, fraction (–0.08 mm), NaOH/S ratio = 100 g/100 g in 1 dm3 of the solution. The proposed method for processing copper skimmings will allow one to selectively isolate arsenic into the dump waste product during subsequent precipitation and separate contaminant from lead-copper cake, into which precious metals also pass. Such an approach provides the reduction of arsenic circulation between the lead and copper manufacturing facilities.

Studying Kinetics of Arsenic Recovery from Copper Dross by Alkaline Sulfide Leaching

2019 ◽  
Vol 946 ◽  
pp. 547-551
Author(s):  
A.A. Nabiyeva ◽  
N.A. Kulenova ◽  
S.V. Mamyachenkov
Keyword(s):  
Arsenic Removal ◽  
Precious Metals ◽  
Production Cycle ◽  
Arsenic Content ◽  
Destructive Effect ◽  
Lead Production ◽  
Lead Bullion ◽  
Removal Of Arsenic ◽  
Kinetics Of ◽  
Alkaline Sulfide

Copper dross are produced by rough decopperizing of blast furnace lead bullion. During liquation separation of copper dross from lead bullion most of arsenic and copper are concentrated in copper dross, arsenic content is approximately 4% As. Currently the processes for arsenic recovery from copper dross are understudied. In this work the focus is given to studying kinetics of the process for recovering arsenic from copper dross by alkaline-sulfide leaching. Alkaline sulfide leaching allows carrying out selective removal of arsenic into solution, keeping at this non-ferrous and precious metals in leaching residue. The studied method of alkaline sulfide leaching of copper dross provides backgrounds for developing technology that would allow processing of copper dross with selective arsenic removal from lead production cycle. By minimizing circulation of this harmful impurity in lead production it is possible to lessen destructive effect of its aggressive compounds on smelting-units refractory. Kinetics of alkaline sulfide leaching of copper dross was understudied up to date. This work is an attempt to fill the gap.

The Management of Post-Tonsillectomy Morbidity in Patients With Sleep Apnoea

2019 ◽  
Vol 70 (10) ◽  
pp. 3738-3740
Keyword(s):  
Day Surgery ◽  
Sleep Apnoea ◽  
Integrative Approach ◽  
Multicenter Studies ◽  
Therapeutic Modalities ◽  
Advantages And Disadvantages ◽  
Obstructive Sleep ◽  
Wide Range ◽  
The Impact ◽  
Surgery Center

The Tonsillectomy in children or adults is an intervention commonly encountered in the ENT (Ear Nose and Throat) and Head and Neck surgeon practice. The current tendency is to perform this type of surgery in major ambulatory surgery centers. Two objectives are thus pursued: first of all, the increase of the patient quality of life through the reintegration into the family as quickly as possible and secondly, the expenses associated with continuous hospitalization are reduced. Any tertiary (multidisciplinary) sleep center must ensure the complete diagnosis and treatment (including surgery) of sleep respiratory disorders. Under these conditions the selection of patients and especially the implementation of the specific protocols in order to control the postoperative complications it becomes essential. The present paper describes our experience of tonsillectomy as treatment for selected patients with chronic rhonchopathy (snoring) and mild to moderate obstructive sleep apnoea. It was presented the impact of antibiotics protocols in reducing the main morbid outcomes following tonsillectomy, in our day surgery center. The obtained results can also be a prerequisite for the integrative approach of the patients with sleep apnoea who were recommended surgical treatment. Considering the wide range of therapeutic modalities used in sleep apnoea, each with its specific advantages and disadvantages, more extensive and multicenter studies are needed. Keywords: post-tonsillectomy morbidity, day surgery center, sleep disorders

The Good, the Bad and the Ugly
. A Broad look at the Adaptation of Technology in Education

2020 ◽  
Vol 2 (1) ◽  
pp. 31-44
Author(s):  
Vladislav Ilin
Keyword(s):  
Technology In Education ◽  
Advantages And Disadvantages ◽  
Standardized Method ◽  
Impact Of Technology ◽  
The Impact ◽  
The Way

Technology in education is a global phenomenon affecting learners of all ages. The breadth and variety of available tools make it difficult to implement a standardized method for assessing the impact of technology on learning. The lack of a consensus on good and bad practices results in inconsistent application and mixed learning results.   This article takes a look at the adaptation of technology to education and examines the various tools used to enhance learning. We discuss the advantages and disadvantages of using technology, as well as review methodologies for evaluating the impact.   The essay concludes by identifying several problems with the way technology is evaluated and offers suggestions for further research to address those problems.

Unfunded Public Employee Health Care Benefits and GASB No. 45

2007 ◽  
Vol 21 (3) ◽  
pp. 245-263 ◽  
Author(s):  
Elizabeth K. Keating ◽  
Eric S. Berman
Keyword(s):  
Health Care ◽  
Financial Reporting ◽  
Full Range ◽  
Financial Reports ◽  
Employment Benefits ◽  
Care Plans ◽  
Advantages And Disadvantages ◽  
Government Accounting ◽  
The Government ◽  
The Impact

The Government Accounting Standards Board (GASB) recently released Statement No. 45, Accounting and Financial Reporting by Employers for Post-Employment Benefits Other Than Pensions and its companion Statement No. 43 for pooled stand-alone health care plans, which will profoundly affect American governmental finance. The goal of this article is to encourage governments to consider carefully a full range of options in funding and restructuring other post-employment benefits (OPEB). This article will review Statement No. 45's potential impact on governments and review existing disclosures in financial reports as well as bond offering statements. The article will discuss the statement's impact on budgets and governmental operations, including collective bargaining. Funding options under Statement No. 45 will be detailed, including the advantages and disadvantages of irrevocable trusts and OPEB bonds. The article will also discuss the impact of Medicare Part D subsidies received by governments, as well as the bond rating implications of policy decisions surrounding OPEB. As the largest government entities are just now implementing GASB Statement No. 45, estimates of the magnitude of unfunded OPEB liabilities are limited as are the strategies likely to be adopted to cover these obligations. This article offers a summary of the unfunded OPEB liabilities reported by states and major cities and suggests some measures for assessing the ability of these entities to address these costs.

scholarly journals Potential Impact of the Current and Future Climate on the Yield, Quality, and Climate Suitability for Tea [Camellia sinensis (L.) O. Kuntze]: A Systematic Review

Agronomy ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 619
Author(s):  
Sadeeka Layomi Jayasinghe ◽  
Lalit Kumar
Keyword(s):  
Climate Change ◽  
Future Climate ◽  
Mitigation Strategies ◽  
Extreme Weather Events ◽  
Impact Of Climate Change ◽  
Advantages And Disadvantages ◽  
Tea Quality ◽  
Climate Suitability ◽  
Yield Quality ◽  
The Impact

Even though climate change is having an increasing impact on tea plants, systematic reviews on the impact of climate change on the tea system are scarce. This review was undertaken to assess and synthesize the knowledge around the impacts of current and future climate on yield, quality, and climate suitability for tea; the historical roots and the most influential papers on the aforementioned topics; and the key adaptation and mitigation strategies that are practiced in tea fields. Our findings show that a large number of studies have focused on the impact of climate change on tea quality, followed by tea yield, while a smaller number of studies have concentrated on climate suitability. Three pronounced reference peaks found in Reference Publication Year Spectroscopy (RYPS) represent the most significant papers associated with the yield, quality, and climate suitability for tea. Tea yield increases with elevated CO2 levels, but this increment could be substantially affected by an increasing temperature. Other climatic factors are uneven rainfall, extreme weather events, and climate-driven abiotic stressors. An altered climate presents both advantages and disadvantages for tea quality due to the uncertainty of the concentrations of biochemicals in tea leaves. Climate change creates losses, gains, and shifts of climate suitability for tea habitats. Further studies are required in order to fill the knowledge gaps identified through the present review, such as an investigation of the interaction between the tea plant and multiple environmental factors that mimic real-world conditions and then studies on its impact on the tea system, as well as the design of ensemble modeling approaches to predict climate suitability for tea. Finally, we outline multifaceted and evidence-based adaptive and mitigation strategies that can be implemented in tea fields to alleviate the undesirable impacts of climate change.

scholarly journals Evaluation of offshore wind power in the China sea

2021 ◽  
pp. 014459872199226
Author(s):  
Yu-chi Tian ◽  
Lei kou ◽  
Yun-dong Han ◽  
Xiaodong Yang ◽  
Ting-ting Hou ◽  
...  
Keyword(s):  
Wind Energy ◽  
Wind Power ◽  
Energy Development ◽  
Offshore Wind ◽  
Human Beings ◽  
Offshore Wind Power ◽  
Business Operation ◽  
Advantages And Disadvantages ◽  
Wind Energy Development ◽  
The Impact

With resource crisis and environmental crisis increasingly grim, many countries turn the focus to pollution-free and renewable wind energy resources, which are mainly used for offshore wind power generation, seawater desalination and heating, etc., on the premise that the characteristics of resources are fully grasped. In this study, the evaluation of offshore wind energy in offshore waters in China, as well as the advantages and disadvantages of existing studies were overviewed from four aspects: the spatial-temporal characteristics of wind energy, wind energy classification, the short-term forecast of wind energy and the long-term projection of wind energy, according to the research content and the future considerations about wind energy evaluation (evaluation of wind energy on islands and reefs, the impact of wind energy development on human health) were envisaged, in the hope of providing a scientific basis for the site selection and business operation ‘or military applications’ here (after business operation), etc. of wind energy development, ‘aritime navigation against environmental construction,’ here and also contributing to the sustainable development and health of human beings.

scholarly journals A Review of Computer-Aided Expert Systems for Breast Cancer Diagnosis

Cancers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2764
Author(s):  
Xin Yu Liew ◽  
Nazia Hameed ◽  
Jeremie Clos
Keyword(s):  
Breast Cancer ◽  
Machine Learning ◽  
Deep Learning ◽  
Main Process ◽  
Learning Approaches ◽  
Learning Methods ◽  
Advantages And Disadvantages ◽  
Computer Aided ◽  
Conventional Methods ◽  
The Impact

A computer-aided diagnosis (CAD) expert system is a powerful tool to efficiently assist a pathologist in achieving an early diagnosis of breast cancer. This process identifies the presence of cancer in breast tissue samples and the distinct type of cancer stages. In a standard CAD system, the main process involves image pre-processing, segmentation, feature extraction, feature selection, classification, and performance evaluation. In this review paper, we reviewed the existing state-of-the-art machine learning approaches applied at each stage involving conventional methods and deep learning methods, the comparisons within methods, and we provide technical details with advantages and disadvantages. The aims are to investigate the impact of CAD systems using histopathology images, investigate deep learning methods that outperform conventional methods, and provide a summary for future researchers to analyse and improve the existing techniques used. Lastly, we will discuss the research gaps of existing machine learning approaches for implementation and propose future direction guidelines for upcoming researchers.

scholarly journals Distinct Roles of Acidophiles in Complete Oxidation of High-Sulfur Ferric Leach Product of Zinc Sulfide Concentrate

2020 ◽  
Vol 8 (3) ◽  
pp. 386 ◽  
Author(s):  
Maxim Muravyov ◽  
Anna Panyushkina
Keyword(s):  
Microbial Community ◽  
Zinc Sulfide ◽  
Elemental Sulfur ◽  
Waste Product ◽  
Sulfur Oxidation ◽  
Low Grade ◽  
Sulfide Concentrates ◽  
Sulfide Concentrate ◽  
Elemental Sulfur Oxidation ◽  
Ferric Leaching

A two-step process, which involved ferric leaching with biologically generated solution and subsequent biooxidation with the microbial community, has been previously proposed for the processing of low-grade zinc sulfide concentrates. In this study, we carried out the process of complete biological oxidation of the product of ferric leaching of the zinc concentrate, which contained 9% of sphalerite, 5% of chalcopyrite, and 29.7% of elemental sulfur. After 21 days of biooxidation at 40 °C, sphalerite and chalcopyrite oxidation reached 99 and 69%, respectively, while the level of elemental sulfur oxidation was 97%. The biooxidation residue could be considered a waste product that is inert under aerobic conditions. The results of this study showed that zinc sulfide concentrate processing using a two-step treatment is efficient and promising. The microbial community, which developed during biooxidation, was dominated by Acidithiobacillus caldus, Leptospirillum ferriphilum, Ferroplasma acidiphilum, Sulfobacillus thermotolerans, S. thermosulfidooxidans, and Cuniculiplasma sp. At the same time, F. acidiphilum and A. caldus played crucial roles in the oxidation of sulfide minerals and elemental sulfur, respectively. The addition of L. ferriphilum to A. caldus during biooxidation of the ferric leach product proved to inhibit elemental sulfur oxidation.

Socio-economic preconditions of resort agglomerations development in the south of Russia

2018 ◽  
Vol 10 (4) ◽  
pp. 467-477 ◽  
Author(s):  
Matvey S. Oborin ◽  
Irina Kozhushkina ◽  
Tatyana Gvarliani ◽  
Nikolay Ivanov
Keyword(s):  
Natural Resource ◽  
Federal District ◽  
Tourism Industry ◽  
Infrastructure Development ◽  
The South ◽  
Health Tourism ◽  
Resource Potential ◽  
Content Type ◽  
Advantages And Disadvantages ◽  
The Impact

Purpose This paper aims to analyze the modern problems and the main trends of development of the health-improving tourism sector in the southern part of Russia and to identify significant factors in overcoming the complex challenges related to specific socio-economic conditions in the study area. Design/methodology/approach The material that served as the basis of the study comprises statistical data from the Southern Federal District and its subjects, as well as data about the development of tourism infrastructure on the official websites of governments, Ministry of Tourism and the population of the Southern Federal District. This information was systematized from a number of perspectives, including identification of the chronology of health-improving tourism infrastructure development in the chosen territory, as well as the advantages and disadvantages in this area. Based on the results of the study, the authors also developed some recommendations to overcome existing inactive trends in the field of health tourism. Findings This paper sheds light on the understanding of the challenges and changes that took place in the resort agglomerations of the south of Russia in terms of current issues and those that must be addressed in the coming years. It was concluded that health tourism in the south of Russia has old traditions based on the natural resource potential of territories that are included in the composition of the Southern Federal District. At the same time, the authors came to the conclusion that, unfortunately, not resort agglomerations are fully utilized. Furthermore, some historic resorts were not well maintained by local authorities and have suffered more recently because of lack of investment. At present, the financial results of health resorts and others related to health-improving tourism are precarious as most operations are unprofitable, and so complex decisions are needed to address the underlying problem of resource optimization because of the important social and economic role of the cities in this region. They have special natural and resource potential and preserve traditions related to health-improving tourism. Research limitations/implications The paper provides a conceptual analysis based on limited empirical data combined with some directions for further research. Originality/value The paper attempts to reveal the impact of social, economic and geopolitical factors, both negative and positive, on the development of the health-improving tourism segment, restructuring of the Russian tourism market and the emergence of promising opportunities and new directions for development. The findings also provide insights for practitioners and researchers, and the tourism industry can draw on this analysis to guide the development of strategy, increase investment attractiveness, make more effective use of the natural resource potential and maintain pressure on government partners to provide support to tourism.

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