South African Journal of Science最新文献_第5页

One-pot hydrothermal green synthetic approach of fluorescent carbon dots as optical probes for 2-nitrophenol 荧光碳点作为2-硝基苯酚光学探针的一锅水热绿色合成方法

4区综合性期刊

South African Journal of Science Pub Date : 2023-09-28 DOI: 10.17159/sajs.2023/13921

Pogisego Dinake, Norma Phokedi, Mbhatshi M. Keetile, Mmamiki A. Botlhomilwe, Mogomotsi Tlhako, Bokang Present, Janes Mokgadi, Rosemary Kelebemang

{"title":"One-pot hydrothermal green synthetic approach of fluorescent carbon dots as optical probes for 2-nitrophenol","authors":"Pogisego Dinake, Norma Phokedi, Mbhatshi M. Keetile, Mmamiki A. Botlhomilwe, Mogomotsi Tlhako, Bokang Present, Janes Mokgadi, Rosemary Kelebemang","doi":"10.17159/sajs.2023/13921","DOIUrl":"https://doi.org/10.17159/sajs.2023/13921","url":null,"abstract":"The pursuit of a cost-effective and green synthetic approach to chemical sensors and their application in the sensing of toxic and harmful substances is a never-ending exercise for scientists and researchers. Preparation of fluorescent carbon dots (C-dots) from biomass using water as a solvent and a hydrothermal autoclave to provide the required synthesis temperature offers a cheap and environmentally friendly synthetic approach. Herein, we report a faster, less costly and ecofriendly hydrothermal synthetic approach of carbon dots from Citrullus vulgaris peels as a precursor. The as-prepared carbon dots exhibited hydroxyl, carbonyl and amide functional groups on the surface and an amorphous structure with a particle size distribution of 1.7–3.0 nm. Moreover, the carbon dots displayed intense blue emission fluorescence at 470 nm after excitation at 400 nm. The as-prepared carbon dots demonstrated effective application without further modification towards the selective and sensitive optical recognition of 2-nitrophenol used in the manufacture of explosives. A limit of detection of 2.28×10−7 M was achieved, and no fluorescence quenching was observed in the presence of other nitroaromatic and benzene derivatives indicating excellent selectivity towards 2-nitrophenol. Finally, further studies are required to investigate the potential for the as-prepared carbon dots to monitor nitroaromatic pollutants in real environmental systems.","PeriodicalId":21928,"journal":{"name":"South African Journal of Science","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135385469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The value of multibeam bathymetry in marine spatial planning in South Africa: A review 多波束测深在南非海洋空间规划中的价值综述

4区综合性期刊

South African Journal of Science Pub Date : 2023-09-28 DOI: 10.17159/sajs.2023/14320

Thamsanqa F. Wanda, Errol A. Wiles, Hayley C. Cawthra, Anton de Wit

{"title":"The value of multibeam bathymetry in marine spatial planning in South Africa: A review","authors":"Thamsanqa F. Wanda, Errol A. Wiles, Hayley C. Cawthra, Anton de Wit","doi":"10.17159/sajs.2023/14320","DOIUrl":"https://doi.org/10.17159/sajs.2023/14320","url":null,"abstract":"Given a growing global population and shift to embrace the blue economy, a need for marine spatial planning (MSP) has emerged in South Africa to sustainably resolve the rising conflicts over the use of marine and seabed resources and services. A well-developed marine spatial plan yields numerous ecological, social and economic benefits. These are achieved through mediating between spatially conflicting economic drivers’ interests (e.g. commercial fishing, tourism, mining), preventing their activities from compromising thresholds of an environment’s sustainability. Within the MSP framework, high-resolution geospatial datasets are required to document and describe the seabed in the highest possible detail. At any scale, integrated analysis of seabed geomorphology and habitats is anticipated to greatly improve the understanding of ecosystem functioning from a multidisciplinary perspective, whilst improving MSP procedures and management of marine space. South Africa is the first of few African countries to have an approved and implemented MSP framework, but is still somewhat behind globally in implementing large-scale regional hydroacoustic surveys to cover the country’s vast offshore territory. The deficiency of hydroacoustic surveys is perhaps due to a relative lack of funds and poor communication about the value of multibeam echo-sounder (MBES) derived data, whilst marine geoscience remains a scarce skill in the country. This review paper presents a geological perspective of MSP and explores (1) the value that seabed mapping offers MSP specifically and (2) the need to increase seabed mapping with MBES, using a recently initiated project from the South African east coast as a case study.","PeriodicalId":21928,"journal":{"name":"South African Journal of Science","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135344741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Responding to load shedding 响应负载下降

4区综合性期刊

South African Journal of Science Pub Date : 2023-09-28 DOI: 10.17159/sajs.2023/16836

Leslie Swartz

引用次数: 0

Load shedding in South Africa: Another nail in income inequality? 南非减负:收入不平等的又一根钉子?

IF 2.4 4区综合性期刊

South African Journal of Science Pub Date : 2023-08-31 DOI: 10.17159/sajs.2023/16597

R. Inglesi‐Lotz

引用次数: 0

Load shedding as a result of failures at the political-technological interface 政治技术接口故障导致的甩负荷

IF 2.4 4区综合性期刊

South African Journal of Science Pub Date : 2023-08-31 DOI: 10.17159/sajs.2023/16595

M. Muller

引用次数: 0

Some real but mostly unconsidered costs hiding in the dark corners of load shedding 一些真实但大多未经考虑的成本隐藏在甩负荷的黑暗角落

IF 2.4 4区综合性期刊

South African Journal of Science Pub Date : 2023-08-31 DOI: 10.17159/sajs.2023/16596

M. J. Booysen, S. van der Berg, Pieter W. van der Walt

引用次数: 0

Data gaps will leave scientists ‘in the dark’: How load shedding is obscuring our understanding of air quality 数据缺口将使科学家们“处于黑暗之中”:负荷减少是如何模糊我们对空气质量的理解的

IF 2.4 4区综合性期刊

South African Journal of Science Pub Date : 2023-08-31 DOI: 10.17159/sajs.2023/16009

C. Wright, Matthew Benyon, N. Mahlangeni, T. Kapwata, T. Laban, R. Garland

引用次数: 0

The impact of the increasing residential battery backup systems on load shedding 日益增加的住宅电池备用系统对减载的影响

IF 2.4 4区综合性期刊

South African Journal of Science Pub Date : 2023-08-31 DOI: 10.17159/sajs.2023/16602

M. Ritchie, J. Engelbrecht, M. J. Booysen

引用次数: 0

Liquified petroleum gas provides a technically viable and financially feasible means to reduce Eskom’s diesel cost burden by 30% to 40% 液化石油气提供了一种技术上可行、经济上可行的方法，可以将Eskom的柴油成本负担降低30%至40%

IF 2.4 4区综合性期刊

South African Journal of Science Pub Date : 2023-08-31 DOI: 10.17159/sajs.2023/16594

S. Clark, C. McGregor

引用次数: 0

Resilience is not enough: The mental health impact of the ongoing energy crisis in South Africa 韧性是不够的：南非持续能源危机对心理健康的影响

IF 2.4 4区综合性期刊

South African Journal of Science Pub Date : 2023-08-31 DOI: 10.17159/sajs.2023/16608

M. Marchetti-Mercer

{"title":"Resilience is not enough: The mental health impact of the ongoing energy crisis in South Africa","authors":"M. Marchetti-Mercer","doi":"10.17159/sajs.2023/16608","DOIUrl":"https://doi.org/10.17159/sajs.2023/16608","url":null,"abstract":"limited electricity supply by installing inverters, generators and solar panels in their homes and workplaces. The constant disruptions brought about by blackouts have led to an overwhelming sense of frustration and uncertainty, as people feel they have no control of their lives and environment. Breakages, cable theft, and sabotage exacerbate the situation by adding unscheduled outages, some for as long as 10 days. Outages are also increasingly leading to water shortages as reservoirs cannot refill in the short periods between outages, and to telecommunication problems. Significantly, such disruptions in work and educational activities, as well as in the domestic domain, have been shown internationally to increase psychological distress. 7 Disruption in electricity supply potentially further affects people’s physical health, which can in turn increase people’s risk of developing mental health problems. At the most basic level, food safety is affected as constant refrigeration cannot be guaranteed, placing people at risk of food poisoning and diarrhoeal diseases. Water purification systems also require electricity to function optimally, so load shedding leaves people without water or facing the threat of contaminated water. 7 South Africa has recently experienced a cholera outbreak and the contamination of rivers and sea water in different provinces, because sewage plants did not have electricity. 8,9","PeriodicalId":21928,"journal":{"name":"South African Journal of Science","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45947455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0