Environment and Natural Resources Research最新文献

{"title":"Multi-Layered Cloud Distribution Over Tropical Station Using Radiosonde Humidity Observations and CloudSat Measurements","authors":"K. Subrahmanyam, K. K. Kumar","doi":"10.5539/ENRR.V9N3P9","DOIUrl":"https://doi.org/10.5539/ENRR.V9N3P9","url":null,"abstract":"Owing to its importance of role played by multi-layered clouds in climate of earth’s atmosphere, a decadal observation (January, 2000 to December, 2009) from India Meteorological Department, Trivandrum regular radiosonde (00 & 12 UTC) ascents and CloudSat observations were used to study the distribution of multi-layered cloud formation at this location. Both the ground and space based observations at Trivandrum locations shows the more or less same percentage of occurrence of single-, double-, three-, four- and five-layered clouds. The important findings are: Radiosonde derived cloud ‐free cases and one to five cloud layers account for 30.63%, 42.51%, 19.76%, 5.85%, 1.08%, and 0.16% all cases, respectively, whereas CloudSat shows 47.17%, 24.74%, 6.41%, 1.81%, 0.13% of the total samples, respectively. In general, the thickness of cloud layers does not change much from summer to winter. However, the occurrences of multi-layered clouds are more frequent in the summer. Further, keeping the CloudSat limitations in view, an attempt is made to evaluate the CloudSat observations using radiosonde measurements and which has the great potential for studying the multi-layered cloud structures over the globe and important in climate point of view.","PeriodicalId":11699,"journal":{"name":"Environment and Natural Resources Research","volume":"746 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78780041","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Benchmarking on Water Resource Utilization Efficiency of Prefecture-Level Cities in Jiangxi, China: A Bootstrap-DEA Approach with Three-Stage DEA Models","authors":"Mianhao Hu, Yunling Hu, Juhong Yuan","doi":"10.5539/ENRR.V9N3P14","DOIUrl":"https://doi.org/10.5539/ENRR.V9N3P14","url":null,"abstract":"China has long been adopted traditional data envelopment analysis (DEA) models to measure water resources utilization efficiency of different provinces and cities without bias correction of efficiency scores. In this study, the Bootstrap-DEA approach embedded 3-stage DEA models was introduced to analyze the comprehensive efficiency of water resources utilization in the different prefecture-level cities Jiangxi and tried to improve the application of this method for benchmarking and inter-regional research. It is found that the bias corrected efficiency scores of Bootstrap-DEA differ significantly from those of the traditional DEA model, which implies that Chinese researchers need to update their DEA models for more scientific calculation of water resources utilization efficiency scores. This research has helped narrow the inter-regional gap in the comprehensive efficiency measurement and improvement of water resources utilization. It is suggested that Bootstrap-DEA embedded 3-stage DEA models be widely applied into afterward research to measure comprehensive efficiency of water resources utilization in regional inter-city so as to better serve for efficiency improvement and related decision making.","PeriodicalId":11699,"journal":{"name":"Environment and Natural Resources Research","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73640444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Micro Combined Heat and Power Systems – Evaluation of a Sample Application","authors":"Anayo Ezeamama, E. Albrecht","doi":"10.5539/ENRR.V9N3P1","DOIUrl":"https://doi.org/10.5539/ENRR.V9N3P1","url":null,"abstract":"The growing need for a secure, cost-effective, less polluting and efficient form of energy has contributed to an increasing interest in the use of micro combined heat and power (MCHP) systems. In this paper, the environmental performance and economic feasibility of a 1 kWe internal combustion engine (ICE) MCHP system in a one-family house was assessed and compared with the baseline scenario were residential energy demands are met with grid electricity and natural gas fired condensing boilers. The result of the analysis shows that MCHP systems present opportunities for savings in energy costs. Based on a social discount rate (SDR) of 5 % and a calculated 3259 operating hours, a simple payback period of about 4.8 years was derived as the time needed to recover the extra investment cost of the ICE unit. The result of the sensitivity analysis reveals that, both the running hours and price of electricity have significant effects on the payback period of the project. Considering the end of useful life period of the systems, MCHP offer a good replacement for conventional gas boilers of 90 % efficiency. However, their high initial costs (when compared to high efficiency condensing boilers), could be seen as the major factor hampering market diffusion. Also, considering the optimal environmental benefits, MCHP system produced more on-site CO2 emissions in reference to the condensing boiler but generally, annual CO2 emission is reduced by about 38 % when compared to the overall separate generation of heat and power scenario.","PeriodicalId":11699,"journal":{"name":"Environment and Natural Resources Research","volume":"35 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83726439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Processing of Superfine and Ultrafine Phosphate of a Phosphomud (Part Two)","authors":"S. Ibrahim, K. Yassin, T. Boulos","doi":"10.5539/ENRR.V9N2P102","DOIUrl":"https://doi.org/10.5539/ENRR.V9N2P102","url":null,"abstract":"Mineral industries in common generate a lot of rejects in the form of fines and slimes, which ultimately create environmental and social problems besides causing losses of mineral values. In view of the recent stringent policy imposed on the environment, there is an urgent need to attempt possible simple and cheap solutions to such problems. These slimes have long been considered in the industry to be unrecoverable. It has been standard practice over many years in the phosphate industry to separate and discard the fines and ultrafine particles. \u0000 \u0000In this respect, the present study shed light on the recovery of super and ultrafine phosphate of a phosphomud produced after the processing of an East Mediterranean phosphate ore. Falcon Concentrator model SB40-VFD (semi-continuous with variable frequency drive) was used in this study to recover the -32 micron phosphate fines of D50=11 micron. The effect of the main variables of the semi-continuous Falcon concentrator model SB40-VFD, including the bowl rotation frequency Hz, the fluidizing water pressure psi, and feeding rate g/min on the separation efficiency were followed up. In addition, two feeding modes based on a particle size-by-size were tried in this study: The sample was fed as a global -32 micron sample or as two fractions, -32+11 micron, and -11 micron samples. Central Composite Rotatable Design (CCRD) was applied on the Falcon separation of the -11 micron fraction with D50 < 3 micron alone to model and optimize the separation process for the two responses: the recovered phosphate grade and recovery. \u0000 \u0000Results showed that the phosphate fines containing 14.73% P2O5, 15.03% acid insoluble, and 19.07% loss in ignition was recovered with grade and P2O5 recovery reaching 28.29%, and 95.97% in case of separating the overall -32 micron sample as one feed. In case of the fractionated feeding samples, the total grade and recovery reached 29.21%, and 88.42%, respectively. The application of the CCRD results showed that the bowl rotation frequency showed to have the main irreversible effect on the product grade, where the fluidizing water pressure had the main reversible effect on the recovery. On the other hand, feeding rate showed some effect on the product grade with almost no effect on its P2O5 recovery%.","PeriodicalId":11699,"journal":{"name":"Environment and Natural Resources Research","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88183837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Prebiotic Stage and the Evolution of Life on Earth","authors":"G. Ghiorghita, G. Surpateanu","doi":"10.5539/ENRR.V9N2P86","DOIUrl":"https://doi.org/10.5539/ENRR.V9N2P86","url":null,"abstract":"The paper is a synthesis of the information collected so far on the origin and evolution of life on Earth. The life appearance and its evolution is correlated to matter evolution in univers: Big Bang, inorganic, organic, prebiotic, unicellular and multicellular stages. Concerning prebiotic stage in life evolution we present our theory based on syntone chemistry. Three syntones-methylene, nitrene and carbon monoxid carried by molecular nitrogen at law temperature could furnish the prebiotic bricks (sugars, lipids, proteins) at the contact to primary atmosphere components. Also, we think that these syntones could be considered as sources of great number of organic molecules. All organisms on Earth descend from a last universal common ancestor (LUCA). Two branches were derived from LUCA: one led to bacteria and the other to archaea and eukaryotes. The appearance of photosynthesis determined a transition from the oxygen-free atmosphere to the oxic atmosphere. Due to a series of endosymbioses, Eukaryotes emerged as organisms with nucleated cells and aerobic metabolism (which significantly increased the efficiency of cellular energy production). At about the same time appeared the first multicellular organisms. The paper also presents other important moments in the evolution of life on Earth, including the major biological crises in certain periods, resulting in the mass extinction of some groups of organisms. The evolution of the living world on Earth culminated with the emergence of man, the most complex being with language, superior thinking, emotions, creativity, etc.","PeriodicalId":11699,"journal":{"name":"Environment and Natural Resources Research","volume":"51 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85142116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of Technologies for Measuring Exposure to NO2 during Welding on Aluminum Alloys","authors":"T. McManus, A. Haddad","doi":"10.5539/ENRR.V9N2P75","DOIUrl":"https://doi.org/10.5539/ENRR.V9N2P75","url":null,"abstract":"Arc welding is a complex process that results in many air contaminants of health significance to humans. As a result, regulators worldwide require employers to determine exposure of welders and other workers to these contaminants. The very small Exposure Limit for NO2 limits the technology available for assessing exposure. Bias caused by ozone, a known interferent in the measurement of NO2, is a major concern. This investigation involved side-by-side comparison of results provided by handheld instruments containing electrochemical sensors for NO2 to those produced by an air pollution analyzer specific to NO2 using bag samples of plumes collected during production welding (Gas Shielded Metal Arc Welding [GMAW] commonly known as Metal Inert Gas [MIG welding]) on aluminum alloys. The shield gas was argon. Monitoring to confirm utility of the method was performed on welders. Results from all instruments were similar despite differences in measurement technology and instrument and sensor manufacturer. Levels experienced during confirmatory testing on welders to determine exposures of short duration and long intermittency as occur during real-world activity were comparable to the Threshold Limit Value for NO2 of 0.2ppm (parts per million) expressed as a Time-Weighted Average over 8 hours, and were less than the Ceiling Limit of 1ppm used by some jurisdictions. Hand-held instruments containing electrochemical sensors for NO2 and datalogging capability are suitable for use in this application. The ability to draw the sample to the instrument by a pump is an important consideration in providing welder safety and protecting the instrument.","PeriodicalId":11699,"journal":{"name":"Environment and Natural Resources Research","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72993646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Natural Ventilation in Isolated Subsurface Structures in the Infrastructure: A Review","authors":"T. McManus, A. Haddad","doi":"10.5539/ENRR.V9N2P61","DOIUrl":"https://doi.org/10.5539/ENRR.V9N2P61","url":null,"abstract":"The subsurface infrastructure contains many types of structures. Some are networked together in open systems while others are completely independent from each other. This study provides a summary of findings concerning ventilation induced by natural forces from reports published in the literature + additional unreported information concerning isolated subsurface structures. Isolated subsurface structures meet criteria for classification as confined spaces. Isolated subsurface structures experience two-way exchange of the internal atmosphere with the external atmosphere when the manhole cover or access hatch contains one or more openings. This finding is not appreciated by current practitioners of occupational health and safety knowledgeable in the area of confined spaces. Presently identified factors influencing ventilation induced by natural forces include the number/area of openings in the manhole cover, differences in temperature between the interior airspace and the external atmosphere, and air movement along the surface of the ground. Additional factors could include size or number of individual openings, placement of openings in the manhole cover or hatch, shape of the openings, and shape of the path followed during air exchange. In some cases, application of additional analysis provides information contained in the data but not presented in these documents. Demonstrating and understanding the interaction between these factors will enable optimization of design to maximize the rate of air exchange. Optimizing the rate of air exchange is essential to minimizing to the extent possible the risk posed to passersby and to workers engaged in preparation for entry and work inside these structures.","PeriodicalId":11699,"journal":{"name":"Environment and Natural Resources Research","volume":"64 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80862988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Case Study of Enhancing Sustainable Intensification of Chinese Torreya Forest in Zhuji of China","authors":"Xiongwen Chen, Hangbiao Jin","doi":"10.5539/ENRR.V9N2P53","DOIUrl":"https://doi.org/10.5539/ENRR.V9N2P53","url":null,"abstract":"Chinese torreya (Torreya grandis cv. Merrillii) is an important cash tree in southeastern China and this species plays a major role in local economy. Establishing new plantations of Chinese torreya would be necessary in order to receive more economic benefit. However, expanding the area of torreya plantations would conflict with other land-use and also affect regional biodiversity. Under this context, local people and government made a paradigm shift from nuts productivity to sustainable practices. They explored the multi-functionalities of Chinese torreya forests, such as the social, cultural, environmental and health functionalities, and developed ecotourism as a breakthrough. The development of multi-functionalities of torreya plantations greatly improved the local economy and led a success in the local society. The strategy of this case completely followed the principles of sustainable intensification of agriculture and translational ecology, which involve scientists, stakeholders and policy makers to emphasize landscape multi-functionalities and minimize environmental impacts of operations. The knowledge from this study may be helpful to research in other regions.","PeriodicalId":11699,"journal":{"name":"Environment and Natural Resources Research","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88161300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fitting of Probability Distribution on the Post-Monsoon Rainfall of Different Locations in Bangladesh","authors":"M. Rahman","doi":"10.5539/ENRR.V9N2P27","DOIUrl":"https://doi.org/10.5539/ENRR.V9N2P27","url":null,"abstract":"Different probability distributions of post-monsoon rainfall of different locations in Bangladesh are fitted. It is found that, for the data, Weibull distribution for Barisal, Bogra, Chittagong, Comilla, Cox's Bazar, Faridpur, Jessore, Khulna, Maijdi Court, Mymensingh, Satkhira, and Sylhet; the Gamma distribution for Dhaka, Ishurdi, Rangamati, Rangpur, and Srimangal based on graphical assessment and goodness-of-fit criterion. In this study, different probability distributions have been fitted for the data of post-monsoon precipitation for 17 different locations in Bangladesh over the period 1961-2014.","PeriodicalId":11699,"journal":{"name":"Environment and Natural Resources Research","volume":"44 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75675637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Indigenous Knowledge Systems for Local Weather Predictions: A Case of Mukonchi Chiefdom in Zambia","authors":"Mabvuto Mbewe, A. Phiri, N. Siyambango","doi":"10.5539/ENRR.V9N2P16","DOIUrl":"https://doi.org/10.5539/ENRR.V9N2P16","url":null,"abstract":"The purpose of the study was to unravel constituents of the indigenous knowledge systems (IKS) and appreciate people’s experiences in predicting the weather in daily undertakings. The objectives of the study were; to identify factors or systems used, establish the knowledge used in predicting the weather and compare the indigenous and current scientific method of predicting the weather. Qualitative and quantitative research designs were used. Primary data was collected through semi structured, face-to-face and in-depth interviews. This was complemented by secondary data collected through desk reviews of relevant published materials. The findings reveal that indigenous knowledge systems have been employed by people of Mukonchi chiefdom since time immemorial. There has also been reliance on IKS to make decisions pertaining to livelihoods such as agricultural activities. However, IKS in the area remains undocumented. Observation of several occurrences in combination or singularly relating to plants, animals, insects and astronomical events were factors of significant importance in the knowledge of weather extrapolation. Elements such as age, frequency of use of the IKS and level of education were seen to be of momentous prominence in utilisation of the indigenous knowledge as modern means of weather forecasting which are applicable to local community environment.","PeriodicalId":11699,"journal":{"name":"Environment and Natural Resources Research","volume":"23 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80407741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}