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Synthesis, Assessment of Biological Activity and Toxicity for N-(<i>β</i>-D-Glycopyranosyl)-Thiosemicarbazides 被引量:1
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作者 Baktygul Ernazarova Asylkan Dzhumanazarova +4 位作者 Aida Bakirova Zhypargul Abdullaeva Gulsara Zhusupbaeva Zarylkan Asylbek Kyzy Momun Arzybaev 《International Journal of Organic Chemistry》 2020年第4期159-169,共11页
In the modern science, priority is given for the search of biological active compounds with specific properties. As a result of experimental data, it was found that in the reaction between N-(<em>β</em>-D... In the modern science, priority is given for the search of biological active compounds with specific properties. As a result of experimental data, it was found that in the reaction between N-(<em>β</em>-D-glycopyranosyl)-semicarbazide and the Lawesson reagent (2,4-bis(p-methoxyphenyl)-1,3-dithiadiphosphetane 2,4-disulfide) at the ratio 1:1 in pyridine when boiling under reflux in a water bath for 20 - 35 minutes, a new synthetic compound N-(<em>β</em>-D-glycopyranosyl)-thiosemicarbazide is formed. The individuality and structure of the target products were confirmed by 13C NMR spectroscopy, 1H NMR spectroscopy, IR spectroscopy, and elemental analysis. For the synthesized new compounds of N-(<em>β</em>-D-glycopyranosyl)-thiosemicarbazides, the probability of pharmacological and toxic effects were predicted by the computer method in silico. From the synthesized compounds N-(<em>β</em>-D-galactopyranosyl)-thiosemicarbazide, the probability of antibacterial (antibacterial) activity is predicted (<em>Pa</em>/<em>Pi</em> 0.544/0.013). The antibacterial activity of the compound (4) was confirmed in a test for salmonella infection of lambs, salmonellosis of calves, and colipathogenic E. coli serotypes. An experimental study by the in vitro method made it possible to conclude that the new synthetic compound N-(<em>β</em>-D-galactopyranosyl)-thiosemicarbazide in the studied concentrations has a pronounced bactericidal and bacteriostatic effect. The synthetic new compound N-(<em>β</em>-D-glyco- pyranosyl)-thiosemicarbazide is a promising compound for further study. 展开更多
关键词 assessment of biological Activity Synthesis of Carbohydrate Derivatives of Urea Toxicity Antibacterial Antiviral Activity
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The Influence of Alluvial Mining on the Morphology and Ecological Health of the Jhimruk River in Pyuthan, Nepal
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作者 Ankit Kandel Kismat Pokhrel +1 位作者 Lenin Adhikari Deep Narayan Shah 《Journal of Geoscience and Environment Protection》 2023年第8期33-48,共9页
Historically, alluvial rivers have been a desirable source of sediment for various industrial purposes. However, the demand for sand is rapidly increasing, leading to environmental concerns associated with its extract... Historically, alluvial rivers have been a desirable source of sediment for various industrial purposes. However, the demand for sand is rapidly increasing, leading to environmental concerns associated with its extraction. The extraction of sediment from riverbeds has both visible and invisible effects. This research aims to investigate the dynamics of the Jhimruk River’s morphology and its impacts by evaluating the river’s quality and studying its changing morphology. To assess morphological changes, satellite images from different years were compared using Geographic Information System (GIS). Physical assessments were conducted by calculating a Habitat score based on various parameters. Water quality assessments involved measuring factors such as pH, temperature, nitrate levels, and alkalinity. A water quality map of the river was generated using color coding to indicate different conditions. The Habitat score demonstrated variations in the data collected from all sites, with factors such as instream cover, bottom substrate stability, riparian vegetation, and aesthetic of the river stretch playing crucial roles in influencing the total score. The Water Quality Index value for the disturbed site indicated moderate pollution, falling under class II. Aquatic macroinvertebrates displayed natural responses to increasing levels of stressors across their life stages, as observed through the analysis of the GRS-BIOS/ASPT index. With the exception of the disturbed site, all other sites were classified under water quality class II, while the disturbed site belonged to class III, indicating a moderate to critically polluted state for most of the Jhimruk River. Furthermore, an increase of 180.87 meters in the river width at the disturbed site provided evidence of morphological changes occurring over the specified period. Mining activities were identified as a significant contributor to the alteration in river morphology. 展开更多
关键词 Alluvial Mining Physical assessment biological assessment Water Quality assessment Jhimruk River Sand Mining
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Contribution of national bioassessment approaches for assessing ecological water security: an AUSRIVAS case study 被引量:10
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作者 Susan J. NICHOLS Fiona J. DYER 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2013年第5期669-687,共19页
River managers in Australia are managing in the face of extremes to provide security of water supply for people, production and the environment. Balancing the water requirements of people, environments and econo- mies... River managers in Australia are managing in the face of extremes to provide security of water supply for people, production and the environment. Balancing the water requirements of people, environments and econo- mies requires that water security is viewed holistically, not just in terms of the water available for human consump- tion. Common definitions of water security focus on the needs of both humans and ecosystems for purposes such as drinking, agriculture and industrial use, and to maintain ecological values. Information about achieving water security for the environment or ecological purposes can be a challenge to interpret because the watering require- ments of key ecological processes or assets are not well understood, and the links between ecological and human values are often not obvious to water users. Yet the concepts surrounding river health are inherently linked to holistic concepts of water security. The measurement of aquatic biota provides a valuable tool for managers to understand progress toward achieving ecological water security objectives. This paper provides a comprehensive review of the reference condition approach to river health assessment, using the development of the Australian River Assessment System (AUSRIVAS) as a case study. We make the link between the biological assessment of river health and assessment of ecological water security, and suggest that such an approach provides a way of reporting that is relevant to the contribution made by ecosystems to water security. The reference condition approach, which is the condition representative of minimally disturbed sites organized by selected physical, chemical, and biological characteristics, is most important for assessing ecological water security objectives. 展开更多
关键词 ecological water security biological assessment river health
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River Water Quality Assessment in Selected Yangtze Tributaries: Background and Method Development 被引量:4
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作者 Sonja C Jhnig 蔡庆华 《Journal of Earth Science》 SCIE CAS CSCD 2010年第6期876-881,共6页
Water pollution is among the most severe environmental problems in China, particularly in the vicinity of residential and urban areas. In almost all Asian countries, river monitoring is predominantly based on the anal... Water pollution is among the most severe environmental problems in China, particularly in the vicinity of residential and urban areas. In almost all Asian countries, river monitoring is predominantly based on the analysis of chemical data. However, biological data are a worthwhile addition for the determination of the long-term ecological status of rivers and are particularly well-suited in case of steep pollution and disturbance gradients. A tool for river water quality assessment using benthic invertebrates has been developed for selected tributaries of the middle reach of the Yangtze River. Site selection was supported by a preclassification considering physico-chemical and hydromorphological conditions. Following a stratified sampling design, 34 samples were taken in small and large streams in the subtropical mountainous area of western Hubei (湖北) (China) covering a pollution gradient, accompanied by an extensive field protocol on stream characteristics and (physico-) chemical water analyses. The proposed assessment system is computed as an average score per taxon. The challenge to further consider the additional impact from global change into the development of such tools is discussed. 展开更多
关键词 benthic invertebrate biological assessment ecological quality organic pollution HUBEI climate change.
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Ecological restoration of small water courses,experiences from Germany and from projects in Beijing
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作者 Walter Binder Albert Göttle Duan Shuhuai 《International Soil and Water Conservation Research》 SCIE CSCD 2015年第2期141-153,共13页
From 2009 until 2012 the project“Watershed Management of Forest Land in Beijing,Restoration of Small Water Bodies(SWBR)”was implemented,combining Close to Nature Forest Management and Restoration of Small Water Bodi... From 2009 until 2012 the project“Watershed Management of Forest Land in Beijing,Restoration of Small Water Bodies(SWBR)”was implemented,combining Close to Nature Forest Management and Restoration of Small Water Bodies.The targets were to improve flood control,to enhance the ecological conditions by copying nature and to support the recreational value of small water bodies,all in cooperation with people living there.The efficiency of each project was proofed by comparison of biological and hydro-morphological assessment before the projects started and 2-3 years after they were finished.The results confirmed the ecological improvements of the restored river sections and showed the achievements.Guidelines to assess the biological and hydro-morphological status of rivers were developed and there are plans to introduce them as Beijing Standards.Planning and implementation of measures,based on experiences in Central Europe,will be documented in a handbook.&2015 International Research and Training Center on Erosion and Sedimentation and China Water and Power Press.Production and Hosting by Elsevier B.V.This is an open access article under the CC BY-NC-ND license(http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 River restoration-rehabilitation Natural-modified rivers European Water Framework Directive Reference status biological and hydro-morphological assessment methods Planning-implementation process
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