MEMBRANE SELECTION FOR ORGANIC CONTAMINANTS REMOVAL FROM HARTBEESPOORT DAM WATER IN SOUTH AFRICA

Scientists have identified a series of milestones in the evolution of the human food quest that are anticipated to have had far-reaching impacts on biological, behavioural and cultural evolution: the inclusion of substantial portions of meat, the broad spectrum revolution and the transition to food production. The foraging shift to dense and predictable resources is another key milestone that had consequential impacts on the later part of human evolution. The theory of economic defendability predicts that this shift had an important consequence—elevated levels of intergroup territoriality and conflict. In this paper, this theory is integrated with a well-established general theory of hunter–gatherer adaptations and is used to make predictions for the sequence of appearance of several evolved traits of modern humans. The distribution of dense and predictable resources in Africa is reviewed and found to occur only in aquatic contexts (coasts, rivers and lakes). The palaeoanthropological empirical record contains recurrent evidence for a shift to the exploitation of dense and predictable resources by 110 000 years ago, and the first known occurrence is in a marine coastal context in South Africa. Some theory predicts that this elevated conflict would have provided the conditions for selection for the hyperprosocial behaviours unique to modern humans. This article is part of the themed issue ‘Major transitions in human evolution’.

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Growth of carbon structures on chrysotile surface for organic contaminants removal from wastewater

Chemosphere ◽

10.1016/j.chemosphere.2016.06.022 ◽

2016 ◽

Vol 159 ◽

pp. 602-609 ◽

Cited By ~ 2

Author(s):

Bruno R.S. Lemos ◽

Érico A.R. Soares ◽

Ana Paula C. Teixeira ◽

José D. Ardisson ◽

Luis E. Fernandez-Outon ◽

...

Keyword(s):

Organic Contaminants ◽

Carbon Structures ◽

Contaminants Removal

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Synergetic Effect of Combined CaO2 and Microwave Treatment on Waste Active Sludge Dewaterability and Organic Contaminants’ Removal

Frontiers in Environmental Science ◽

10.3389/fenvs.2021.734277 ◽

2021 ◽

Vol 9 ◽

Author(s):

Jie Wang ◽

Kankan Shang ◽

Liangjun Da ◽

Xingguo Liu ◽

Yongjing Zhao ◽

...

Keyword(s):

Organic Contaminants ◽

Superoxide Anion ◽

Extracellular Polymeric Substances ◽

Synergetic Effect ◽

Microwave Treatment ◽

Sludge Dewatering ◽

Active Sludge ◽

Capillary Suction ◽

Contaminants Removal ◽

Sludge Dewaterability

This study investigated the synergetic effect of the combined calcium peroxide (CaO2) and microwave (MW) treatment on waste active sludge dewatering properties and organic contaminants’ removal. The optimal sludge dewaterability was obtained at CaO2 (20 mg/gVSS)/MW (70°C), and the capillary suction time decreased by 52% compared with raw sludge. Further investigation indicated that total extracellular polymeric substances (EPS), tightly bound EPS, total protein, and protein present in tightly bound EPS were closely correlated with sludge dewaterability. Tryptophan, aromatic protein–like substances and humic acid–like substances were the key compounds that affect sludge dewaterability. The charge neutralization and bridge effect of cation ions were strengthened when combined with MW irradiation. In addition, it was revealed that MW facilitated CaO2 to produce more hydroxyl and superoxide anion radicals. This study confirmed CaO2/MW to be an effective way to improve sludge dewatering and remove organic pollutants from sludge.

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