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Determining the optimum percentages of fly ash, metakaolin and copper slag by replacing cement and fine aggregate in m30 grade concrete
Get PDFThe overall production of the cement has greatly increased which results lots of problems in environment as it involves the emission of CO2 gas. Environmental concerns, stemming from the high energy expense and carbon dioxide emission associated with cement manufacture have brought about pressures to reduce cement consumption through the use of supplementary materials. Materials such as Metakaolin, fly ash have good pozzolanic activity and are a good material for the production of high strength concrete. Copper slag is a by-product of copper extraction by smelting. Copper slag can be used in concrete production as a partial replacement for sand. However, it is expected that the use of Metakaolin, Fly ash and Copper slag in concrete improves the strength properties of concrete.
Keywords: Supplementary cementitious material, Cement, Fine aggregat
Sustainable coastal tourism-an overview
Get PDFAn elementary theory of sustainable coastal tourism mainly depends on the crystal clear water, healthy ecosystem, and well preserved coastal environment. Coastal tourism has drawn worldwide attention and has become extremely competitive as everybody tries to increase their profit in terms of beach visitors, both domestic and international [Joseph, and Pakkeerappa,2015]. Usually, any coastal area growth is always looked at from a business perspective, while the environmental aspect is mostly neglected. This strategy leads towards impractical beachfront development, which has different negative ramifications, on the climate and society. It is uneconomical as it destroys the actual ecological structures, such as the beach scenery, the biodiversity, and the biological system in the ocean and on the land. Also the travel industry exercise at the seaside territory destroys the beach. This study summarizes environmental impacts of coastal Tourism and the sustainable options to make it eco-friendly. The sustainable solutions were suggested for better coastal conservation. Also the study points out the future crisis pertaining to the latest Environmental Impact Assessment (EIA) 2020 by the government of India.
Keywords—Coastal, Sustainable, tour, biodiversity, CRZ, EI
A review on bioflocculation using microalgae for nutrient removal from waste water.
Get PDFIn recent decades, the eutrophication of surface water has become a major environmental concern. Increased concentration of nutrients such as nitrogen and phosphorous lead to eutrophication condition which highlights the demand for effective and economical methods of removing nitrogen and phosphorous from waste water. Bio flocculation using microalgae is an excellent candidate for satisfying the dual purpose of nutrient removal and waste water treatment. It has so many advantages over conventional methods such as toxic free, no chemical is needed, low cost etc. In this review the bio flocculation of microalgae, its mechanisms, applications and harvesting methods are discussed.
Keywords: Bio flocculation, microalgae, nutrient removal, waste water treatment
 
A review on performance – based specification of durable concrete
Get PDFConcrete is the most common and widely used building material because of its relatively low cost, flexibility, and adaptability. Recent historical experience indicates that with exposed to aggressive chloride or carbonation-induced conditions, the reinforced concrete (RC) structures deteriorate prior to the expected service life. This is because of the general assumption that the concrete must be sufficiently durable if the strength requirements are adequate. The variability of concrete arising from the actual concreting procedures, such as placement, consolidation, finishing, and curing, does not take this assumption into account. In other words, the concrete cast for compressive strength in the specimens shows no similarity to the concrete in the actual structure. This paper provides a thorough analysis of the advancements that are taking place to achieve the long-term reliability of RC structures based on performance specifications.
Keywords: reinforced concrete, service life, compressive strength, performance specification, durability, carbonation, chloride ion
Floristic studies on some rare plants in Western Ghats of Nasik District, M. S.
Get PDFThe present study deals with taxonomical aspects along with the observation regarding threats, flowering and fruiting period, precise locations of some rare plants of Western Ghats in Nasik District of Maharashtra. Extensive field visits and botanical excursions were conducted during period of investigation i. e. from 2013-2019 in and around the forest area of Nashik district. The major areas that were explored during study are mainly forest pockets and hills regions of Trimbakeshwar, Brahmhagiri mountains, Anjaneri hills, Adwadi hills, Sinnar and environs hilly ranges, Kelzar hilly areas, Mulher, Salher, etc. During the study: more than 150 species of rare plants belonging to 46 families were recorded. The probable reasons that were observe from the decrease of rare plant species population are destruction of natural habitats due to increasing illegal acquiring of forest land, massive deforestation and rapid urbanization. Also, ex-situ conservation of some plant species within the college botanical garden was attempted. However: the present study highlights an effective and purposeful conservation strategy to be adopted for the sustainable use and conservation of important rare plants in the region
Estudios sobre la población de rotíferos en relación con algunos parámetros físico-químicos de un humedal de agua dulce alimentado con aguas residuales de Bengala Occidental, India.
No full textThe present dissertation provides the results of the study done on the Rotifer population of a sewage fed wetland of West Bengal, India, along with the influence of some physico-chemical parameters on them. The water parameters studied were Water temperature (WT), pH, Dissolved Oxygen (DO), Carbon di Oxide (CO2), Total alkalinity (TA), Dissolved Organic Matter (DOM) and Biological Oxygen Demand (BOD). During the study among the above mentioned water parameters WT varied from 15.5oC to 32.75oC, pH from 7.98 to 8.75, DO from 4.3 mg/lit to 16 mg/lit, CO2 from 00 to 46 mg/lit, TA from 164 mg/lit to 251 mg/lit, DOM from 1.13 mg/lit to 4.73 mg/lit and BOD from 5.62 mg/lit to 28.8 mg/lit. One noticeable feature about the seasonal variation of those parameters in the wetland was that its variation pattern differs in actual magnitude. The wetland had fairly high DO content and pH was always alkaline. The water was also rich in DOM. BOD was moderate and not appreciably high as expected in a polluted aquatic system. The combine effect of above physico-chemical parameters might have promoted the luxurious growth of rotifer population of the wetland.
During the study except the above mentioned physico-chemical parameters of water Rotifer population was also observed. A total of 22 species of 12 genera of rotifer were noticed during study. Among them 11 species were dominant and occur more than six months throughout the study period. This population in the wetland overwhelmingly predominated by Brachionus species. Not only that they were also numerically superior over other. Among Brachionus species, Brachionus angularis was most dominant.
From the statistical analysis different species of rotifer showed positive correlation with pH and inverse correlation with CO2 and TA.
Key Words:- Rotifer, Population, Sewage, Freshwater, Wetland, Physico-chemical, Parameter
India.La presente disertación proporciona los resultados del estudio realizado sobre la población de rotíferos de un humedal alimentado con aguas residuales de Bengala Occidental, India, junto con la influencia de algunos parámetros físico-químicos sobre ellos. Los parámetros del agua estudiados fueron temperatura del agua (WT), pH, oxígeno disuelto (OD), dióxido de carbono (CO2), alcalinidad total (TA), materia orgánica disuelta (DOM) y demanda biológica de oxígeno (DBO). Durante el estudio, entre los parámetros de agua mencionados anteriormente, el WT varió de 15.5oC a 32.75oC, pH de 7.98 a 8.75, OD de 4.3 mg / litro a 16 mg / litro, CO2 de 00 a 46 mg / litro, TA de 164 mg / litro iluminado a 251 mg / litro, DOM de 1.13 mg / litro a 4.73 mg / litro y DBO de 5.62 mg / litro a 28.8 mg / litro. Una característica notable de la variación estacional de esos parámetros en el humedal fue que su patrón de variación difiere en la magnitud real. El humedal tenía un contenido de OD bastante alto y el pH siempre era alcalino. El agua también era rica en DOM. La DBO fue moderada y no apreciablemente alta como se esperaba en un sistema acuático contaminado. El efecto combinado de los parámetros físico-químicos anteriores podría haber promovido el crecimiento exuberante de la población de rotíferos del humedal.Durante el estudio, excepto los parámetros físico-químicos mencionados anteriormente, también se observó la población de rotíferos del agua. Durante el estudio se observaron un total de 22 especies de 12 géneros de rotíferos. Entre ellas, 11 especies fueron dominantes y ocurren más de seis meses durante el período de estudio. Esta población en el humedal predominaba abrumadoramente por especies de Brachionus. No solo que también eran numéricamente superiores a otros. Entre las especies de Brachionus, Brachionus angularis fue la más dominante.A partir del análisis estadístico, diferentes especies de rotíferos mostraron correlación positiva con pH y correlación inversa con CO2 y TA.
Palabras clave: Rotífero, población, aguas residuales, agua dulce, humedal, físico-químico,
parámetro, India
Mecanismos de control de la plataforma Uber sobre sus conductores asociados en la Región Metropolitana de Chile
Get PDFThis article discusses the main control mechanisms implemented by Uber platform in the labour process of its associated drivers in the Metropolitan Region of Chile. The information was gleaned from 12 interviews with Uber drivers residing in the Metropolitan Region between September 2019 and February 2020. It was analyzed through qualitative content analysis with Atlas ti7 software. The analytical framework was mainly taken from the labour process theory; current discussions about new forms of control, developed especifically in the context of digital platforms, were incorporated. The main results show a combination between persistent control elements over time and novel elements incorporated in recent years, specifically through a more efficient introduction of old control methods thanks to new technologies, making both new and old forms of control more instantaneous, opaque and comprehensive. However, there is a predominance of those control mechanisms associated to algorithmic control and the strategy of responsible autonomy.En el presente artículo se describen y analizan los principales mecanismos de control implementados por la plataforma Uber en el proceso de trabajo de sus conductores asociados en la Región Metropolitana de Chile. La información fue producida a través de 12 entrevistas realizadas a conductores de Uber residentes en la Región Metropolitana entre septiembre de 2019 y febrero de 2020, analizadas a través de un análisis cualitativo de contenido con el software Atlas ti7. El marco analítico utilizado fue tomado principalmente de la denominada teoría del proceso de trabajo, incorporando además ciertas discusiones actuales sobre nuevas formas de control elaboradas específicamente para el contexto del trabajo en plataformas digitales. Los principales resultados muestran una combinación entre elementos de control persistentes a lo largo del tiempo y elementos novedosos incorporados en los últimos años, específicamente a través de una introducción de mayor eficacia a métodos de control antiguos gracias a las nuevas tecnologías, haciendo que tanto las formas nuevas como antiguas de control sean más instantáneas, opacas y abarcadoras. Con todo, se observa una predominancia de aquellos mecanismos de control asociados al control algorítmico y a la estrategia de autonomía responsable.
A comparative study on the nutritional value of three Polychaete species used in Shrimp Aquaculture
Get PDFThe potential use of polychaete worms are as a dietary source of protein, lipid, amino acids, and vitamins for aquaculture species and also used for alternative feeds of fish meal and fish oils. Many recent studies have been documented the nutritional benefits of polychaetes for aquaculture species, for their satisfactory food intake and reproductive performance in brood stock.Most of the polychaetes were used in hatcheries are wild caught. The commercial harvesting of polychaetes may leads to the disturbance in the benthic community and the ecosystem and also may leads to the depleting population in the ecosystem. Further the development of polychaete culture is therefore of economic importance beyond that the associated bait supply industry which is acted as the initial catalyst for this development. Hence, the present study has been made with three different polychaete species, to assess the nutritional value of the three species, one from imported (Nereis virens) and two locally available species (Perenereis cultrifera and Glycera sp) for commercial uses of the shrimp aquaculture industry.Key words : Polychaete worms, Perenereis species, fatty acids. amino acids, Minerals
Is dairy wastewater safe for production of edible microbial biomass: A case study of Saras dairy plant at Jaipur, India
Get PDFMismanagement of wastewater at large scale may lead to catastrophic environmental and health consequences. Microbial remediation of wastewater is one of the most effective low-cost solutions. There are also initiatives to use wastewater for production edible biomass as an alternative for protein diets. While much researches were oriented towards maximum recovery of biomass and applications, less were focused on mutagenicity of dairy wastewater. In this study, we examined wastewater of one of the largest dairy industries in Rajasthan for its suitability for microbial biomass production and mutagenicity. Influent wastewater was collected from Saras dairy plant, Jaipur, for over a week. Physiochemical properties of wastewater were examined, such as; temperature, pH, salinity, TSS, TDS, turbidity, conductivity, BOD, COD, total carbon, and total nitrogen. SOS chromotest and Salmonella fluctuation test (TA 98, TA 100 and TA 102) were carried out at variable concentration of wastewater to assess mutagenic activity. Results indicated ideal pH, temperature and salinity, for microbial remediation. High TOC and TKN were also observed in the investigated wastewater, which is few of the prerequisites for single cell production. The ratio of BOD and COD was between 0.3-0.4, making the wastewater ideal for microbial growth. No mutagenic activity was observed by SOS chromotest, all three concentrations (C 0.01, C 0.1, and C 0.2) investigated in this study were <1.5 IF. Likewise, mutagenic ratio for all three types of Salmonella revertants were below 1.2 threshold, for investigated concentrations (C 0.5, C 1, and C 10) of wastewater. Conclusively, examined influent wastewater is less likely to induce mutagenic activity at the investigated concentration. Through physiochemical analysis, the investigated wastewater assumed to be candidate substrate for microbial biomass production
Implications of Covid – 19 Pandemic on Agriculture in Imo State, Nigeria- A Review.
Get PDFAbstract
The outbreak of coronavirus (COVID-19) in the world has negatively affected agriculture and stray animals. The crisis includes revenue losses, poor harvest, mortality, morbidity, famine, travel restrictions and lack of interest agricultural activities. The spread of COVID-19 globally, has paralysed every facet of the economy. It has proved beyond doubt that COVID-19 affected the whole world. The aim of this paper is to understand the implications of COVID-19 through the detailed assessment of the pandemic from the Nigerian perspective. The paper adopted an extensive literature review in order to address the academic gap. This paper further established that COVID-19 will have short to long term negative impacts on Nigerian and African economies respective.
Keywords: COVID-19; Agricultural Farm Labour; Mortality; Morbidity; Socio-Economic