scholarly journals A Review of Flotation Physical Froth Flow Modifiers

Minerals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 864
Author(s):  
Tawona M. Jera ◽  
Clayton Bhondayi
Keyword(s):  
Small Volume ◽  
Negative Impact ◽  
Cell Diameter ◽  
Capital Costs ◽  
The Past ◽  
Froth Flow ◽  
Flotation Cells ◽  
Flotation Cell ◽  
New Challenges ◽  
Industrial Solutions

Over the past few decades, the need to process more minerals while lowering capital costs has led to an increase in the size of flotation cells, e.g., 0.03 m3 to 1000 m3. However, this increase has created new challenges in the operation and design of industrial flotation cells, particularly in terms of froth removal, because the distance the froth must travel increases with an increase in the flotation cell diameter. This has a negative impact on recovery. Physical froth flow modifiers can be used to improve froth removal. Their major functions are to modify and optimise the flow of the froth, improve froth drainage, reduce dead zones, and improve froth flow and removal dynamics. Therefore, physical froth flow modifiers are discussed, evaluated, and compared in this paper. The literature indicates that physical froth flow modifiers such as crowders and launders are used extensively as industrial solutions to enhance froth transport and recovery in large flotation cells. Other modifiers (including froth baffles and froth scrapers) have been found to have a profound effect on local froth phase sub-processes, including drainage and bubble coalescence. However, industrial uptake is either dwindling or limited to small-volume rectangular/U-shaped cells in the case of scrapers, or, there is no uptake at all in the case of froth baffles. Further research on how some of the physical modifiers (e.g., baffles and launders) impact the selectivity of particles is required.

Deliberation, demobilization, and limited empowerment: a survey study on participatory pricing in China

2018 ◽  
Vol 19 (4) ◽  
pp. 694-708 ◽  
Author(s):  
Xuan Qin ◽  
Baogang He
Keyword(s):  
Negative Impact ◽  
Negative Relationship ◽  
Political Activism ◽  
Specific Form ◽  
Public Deliberation ◽  
Survey Study ◽  
High Quality ◽  
Low Level ◽  
The Past ◽  
Significant Negative Impact

AbstractAuthoritarian deliberation has been used widely to describe the specific form of deliberation developed in China. However, whether its practice will strengthen authoritarianism or lead to democratization remains unknown. In this study, we examine this question from the perspective of participants in public deliberation. Surveying the participants in participatory pricings held in Shanghai over the past 5 years, we find that participants’ perception of deliberative quality has a statistically significant negative impact on their level of political activism, while their level of empowerment has a moderating effect on this negative relationship. In this light, Chinese deliberative practices characterized by high-quality deliberation and low-level empowerment are likely to have a demobilization effect; thus, they reinforce the authoritarian rules.

scholarly journals The echographic characteristics of structural and functional development of organs and systems in children born with low birth weight, very low birth weight and extremely low birth weight

2020 ◽  
Vol 1 (3) ◽  
pp. 11-17
Author(s):  
P. E. Khodkevich ◽  
K. V. Кulikova ◽  
V. V. Gorev ◽  
I. A. Deev
Keyword(s):  
Birth Weight ◽  
Low Birth Weight ◽  
Very Low Birth Weight ◽  
Negative Impact ◽  
Extremely Low Birth Weight ◽  
Small Children ◽  
Neuropsychological Development ◽  
The Past ◽  
Functional Development ◽  
Development Of Organs

Over the past decade, an increase in the survival rate of children born with low birth weight, very low birth weight, and extremely low birth weight has been observed in Russian Federation, which is due to transition to new live birth criteria. Premature infants are exposed to a number of adverse factors that have a negative impact on the development of organs and systems, which, in turn, can lead to the occurrence of acute and chronic diseases in various age periods. Therefore, neonatologists and pediatricians are dealing with a new cohort of small children who have particular features of physical and neuropsychological development which may lead to severe debilitating diseases. This review article surveys previous studies evaluating the echographic characteristics of structural and functional development of the urinary, cardiovascular and endocrine systems as a function of body weight at birth and gestational age, and in different age periods.

scholarly journals SCIENTIFIC AND METHODOLOGICAL ASPECTS AND PRACTICAL EXPERIENCE FOR THE FORMATION OF THE EVIDENTIAL BASE OF HAZARD TO HEALTH IN THE POPULATION IN THE ZONE OF INFLUENCE OF WASTE FROM THE PAST ECONOMIC ACTIVITY

2019 ◽  
Vol 96 (11) ◽  
pp. 1038-1044 ◽  
Author(s):  
N. V. Zaitseva ◽  
Irina V. May ◽  
S. V. Klein ◽  
S. S. Khankharev ◽  
A. A. Boloshinova
Keyword(s):  
Heavy Metals ◽  
Drinking Water ◽  
Negative Impact ◽  
Health Hazard ◽  
Harmful Effect ◽  
Morbidity Rate ◽  
Atmospheric Air ◽  
The Past ◽  
Zone Of Influence

There are described an algorithm and methods for collecting the evidential base for causing hazard to the health of the population of Zakamensk (the Republic of Buryatia) in the zone of influence of the waste of the past activities of the Dzhidinsky tungsten-molybdenum combine. The source of danger is lying sands, containing a complex of toxic heavy metals - lead, cadmium, manganese, nickel, chromium, etc. The algorithm for the formation of the evidential base included: a general analysis of the sanitary and hygienic situation; assessment in the dynamics of the quality of atmospheric air, drinking water, soil, food; assessment of the risk to the health of the population; epidemiological studies; in-depth clinical surveys of a representative group of city residents (280 people). In the blood of the examinees, heavy metals were identified as biological markers of the exposure. There was evaluated a complex of the response (effect) adequate to effects of laboratory markers. By methods of mathematical statistics there was established the presence of reliable relationships in the system “source of hazard - the quality of the environment - exposure to risk factors - health status.” The hazard to the health of a citizen, due to the negative impact of the factor, was considered to be proven if it was possible to build a continuous step-by-step logical chain of relationships between the source of the harmful effect, the quality of the habitat and the establishment of the fact of the disease. The quality of the habitat of the population of Zakamensk was shown to give rise in unacceptable risks to the health of residents. The main influencing factor is the pollution of atmospheric air, local food products and drinking water from public and private wells. Risks are realized in terms of a level of the primary morbidity rate of the population of the respiratory diseases, endocrine system, digestive organs that is relatively high compared to the matched area. The relationship between health hazard and environmental factors has been fully proved in 14% of the surveyed persons. At the same time, the territory was shown not be characterized as a zone of “ecological disaster” or “an emergency environmental situation”.

scholarly journals CHINESE SCULPTURE IN THE NEW ERA

2021 ◽  
Vol 17 (5) ◽  
pp. 125-135
Author(s):  
Wei Xiao
Keyword(s):  
Cultural Tradition ◽  
Social Changes ◽  
The West ◽  
New Era ◽  
The Past ◽  
The Future ◽  
National Spirit ◽  
New Challenges ◽  
Cultural Content

With the advent of a new era, universal social changes pose new challenges for the art of sculpture. In terms of cultural content and practice, sculpture needs to keep pace with time. Chinese sculpture should participate in the global processes of modern sculptural development, guided by the literary and artistic concept «do not forget the past, absorb the foreign, look into the future». Not only should it receive inspiration and stimuli for development from the West but find its voice, preserving Chinese cultural tradition and Chinese national spirit.

New challenges in viral hepatitis

Gut ◽  
2012 ◽  
Vol 61 (Suppl 1) ◽  
pp. i1-i5 ◽  
Author(s):  
David Thomas ◽  
Fabien Zoulim
Keyword(s):  
Viral Hepatitis ◽  
Hepatitis Virus ◽  
Virus Infections ◽  
The Past ◽  
Treatment And Prevention ◽  
Introductory Article ◽  
Key Issues ◽  
New Challenges ◽  
Reliable Methods ◽  
Remarkable Progress

Over the past few decades there has been remarkable progress in viral hepatitis. Beginning with discovery of the viral agents, we now have reliable methods to diagnose and monitor all hepatitis virus infections, as well significant advances in treatment and prevention. Nonetheless, important challenges remain. This supplement to Gut looks forward to the next generation of challenges in the field of viral hepatitis, and this introductory article highlights several key issues.

The History of Africanization and the Africanization of History

2006 ◽  
Vol 33 ◽  
pp. 85-100 ◽  
Author(s):  
Esperanza Brizuela-García
Keyword(s):  
Latin American ◽  
Graduate School ◽  
American History ◽  
African Studies ◽  
African History ◽  
Not Given ◽  
Latin American History ◽  
The Past ◽  
History Of ◽  
New Challenges

The idea of Africanization is arguably one of the most important and prevalent in African historiography and African studies. I first encountered this notion some eight years ago when I started graduate school. With a background in Mexican and Latin American history, I found it necessary to immerse myself in the historiography of Africa. It was in this process that I encountered the idea of Africanization. It was not always identified in this manner, but it was clear that historians were, in one way or another, articulating a concern about how “African” was African history.The objective of this paper is to examine the history of Africanization in African historiography. It departs from two basic premises. First, the issues that come with the idea of Africanization are more pronounced in the field of African history. When compared to other fields, such as Latin American history, this indigenizing of history is not given nearly so much attention. Second, the idea that African history needs to be Africanized has been taken for granted, and has not been critically examined. Here I will contend that the historical conditions that have framed the emergence and development of African historiography have made it necessary to emphasize the issue of Africanization. I will also argue that those conditions have changed in the past fifty years, and that the questions raised in the quest to Africanize history should be redefined in view of the new challenges for African history and of historiography at large.

It's all in the past: how do colonial legacies between host and home countries affect the expatriate experience?

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Christopher Richardson
Keyword(s):  
Cultural Values ◽  
Negative Impact ◽  
Research Field ◽  
Content Type ◽  
Colonial Legacy ◽  
The Past ◽  
Host Country Nationals ◽  
Practical Experiences ◽  
The Individual ◽  
The Impact

PurposeWithin the expatriation subset of the wider IB literature, the focus of research has been on contemporary contextual factors. The purpose of this paper is to link the present to the past by investigating how the individual expatriate experience may be affected by a colonial legacy between host and home countries.Design/methodology/approachGiven the exploratory nature of this study, a qualitative interview-based approach eliciting thick, detailed descriptions of the practical experiences of seven Japanese expatriate managers working in Malaysia was adopted. These were supplemented by additional interviews with three host-country nationals who work alongside some of the expatriates. The data were analysed through a two-stage coding process.FindingsThe expatriate respondents were largely unanimous in their view that the colonial past between the two countries had no negative impact on their experiences in Malaysia, and the Malaysian interviewees corroborated this. On the contrary, the majority of the expatriates actually spoke positively about their experiences. This was especially true for expatriates in both the tourism and education/research field whose work was linked in some way to the period of Japanese occupation.Research limitations/implicationsThe small, single-context nature of the investigation limits generalisation. There are also many particularities in this study (the nature of Japanese-Malaysian postcolonial relations, cultural values of the Malaysians and Japanese, and so on) that are perhaps not easily relatable to other contexts. Having said this, qualitative research is not always geared towards generalisability but rather towards contextual intricacies and nuances.Originality/valueWhile most of the extant literature on expatriation has examined largely contemporary factors, this paper explores the impact of more historical events on the expatriate experience. Although such events may seem distant from an expatriate's current activities, this study suggests that in certain circumstances, they may have a lingering effect.

Progress and Prospects for Estonian Libraries

2011 ◽  
pp. 221-237 ◽  
Author(s):  
Sirje Virkus
Keyword(s):  
Information And Communication Technologies ◽  
Information And Communication Technology ◽  
Communication Technology ◽  
Rapid Development ◽  
Communication Technologies ◽  
Library Services ◽  
The Past ◽  
Challenges And Opportunities ◽  
Information And Communication ◽  
New Challenges

The rapid development of information and communication technology (ICT) over the past decades has created new challenges and opportunities for libraries and librarians. As a result of ICT, library services to users have changed, the management of libraries has evolved and the roles of librarians have multiplied. The new millennium presents new opportunities to exploit an ever-growing array of information and communication technologies in the provision of library services. As one millennium draws to a close and a new one begins, there are a lot of questions to answer:

Epilogue

2016 ◽  
pp. 119-122
Author(s):  
Christian W. McMillen
Keyword(s):  
Public Health ◽  
Climate Change ◽  
Lessons Learned ◽  
The Past ◽  
Public Health Infrastructure ◽  
Health Infrastructure ◽  
The World ◽  
The Future ◽  
The Face ◽  
New Challenges

There will be more pandemics. A pandemic might come from an old, familiar foe such as influenza or might emerge from a new source—a zoonosis that makes its way into humans, perhaps. The epilogue asks how the world will confront pandemics in the future. It is likely that patterns established long ago will re-emerge. But how will new challenges, like climate change, affect future pandemics and our ability to respond? Will lessons learned from the past help with plans for the future? One thing is clear: in the face of a serious pandemic much of the developing world’s public health infrastructure will be woefully overburdened. This must be addressed.

Is There Population with Tertiary Education in Romania Still Interested in Research?

2015 ◽  
Vol 4 (4) ◽  
pp. 54-66
Author(s):  
Radu Serban Zaharia ◽  
Marian Zaharia ◽  
Alecu Alexandra
Keyword(s):  
Negative Impact ◽  
Tertiary Education ◽  
Government Policies ◽  
Total Employment ◽  
The Past ◽  
Education And Health ◽  
Material Basis ◽  
Labour Costs ◽  
Low Levels ◽  
The Government

In the past 25 years, in Romania, the intensity of R & D activities has declined significantly in most industries. This trend was driven primarily by the lower attention of the government policies of governments after 1990, resulting in particularly low share of research spending in GDP. This had a double negative impact. On one side was affected material basis of research, while on the other side salary levels of researchers along with education and health, remained at very low levels. Based on these considerations the paper examines the evolution of percentage of researchers in total employment in correlation with factors as: the percentage of population with tertiary educational attainment level, the percentage of total intramural R&D expenditure in GDP, the percentage of R&D labour costs in GDP in Romania, compared to Bulgaria, Czech Republic, France, Hungary and Poland. Unfortunately, in what concerns us, the answer is negative.

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