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A review on study of partial replacement of cement by metakaolin and glenium b233 in self- compacting concrete.
Get PDF Self-compacting concrete (SCC) refers to high strength concrete which will compact under its own weight and does not require external vibration. This paper gives a review on the journals to study the effect of metakaoiln in SCC. The metakaolin is used as a replacement of cement and it is obtained from natural Kaolin clay. Metakaolin helps to increase the compressive strength, spilt tensile strength, flexural strength and also the fresh properties. The use super plasticizer greatly improves pump-ability and the slump value. GLENIUM B233 is a new generation based super plasticizer which is based on modified polycarboxylic ether. The fresh properties such as pump ability and workability and the durability properties of super plasticizer in SCC with metakaolin are discussed.
Keywords: Self-Compacting Concrete, Metakaolin, GLENIUM B233, Superplasticizer, Polycarboxylic Ethe
Sustainability of concrete using recycled aggregate: a review
Get PDFSustainable development is essential to the well-being of our planet, human development, and the continued growth of society. As we know, concrete are the most commonly used substance in the world, after water. However, recycled concrete is the biggest advantage for us. Nowadays the construction industry also tries to replace the virgin material to reduce the environmental impact, global warming, pollution, etc. The construction activity and old structural building also is an issue for the environment. The reuse and recycle of concrete would therefore also reduce the burden on the environment. So this paper will give a summary of recycled concrete aggregate, their sustain on the environment, properties of the application of recycled aggregate, and the resultant of their properties of recycled concrete aggregate.
Keywords- Aggregate, Concrete, Construction Development, Environment, Recycled, Sustainable
Effects of continous cropping and NPK fertilizer on growth and yield of cowpea (Vigna unguiculata (L) Walp) grown on soils from different management systems
Get PDFStudies were conducted to investigate the effect of continuous cropping and NPK fertilizer on the growth and yield of cowpea (Vigna unguiculata (L) Walp) grown on soils from different management systems. The investigations were carried out in two parts. The first dealt with the effect of continuous cropping while the other focused on the effect of NPK fertilizer on cowpea. Representative soil samples were obtained at 0-15 cm depth from land which had been continuously cropped, under forest tree fallow, and secondary bush fallow. These were bulked, processed, and analyzed. Six (6) kg of each type of soil were weighed into 25 x 22 cm polybag of 500 gauge. The continuous cropping experiment involved three cropping cycles of 35days each of cowpea on the same soils from 3 cropping systems. In the second experiment, a 2 x 3 factorial involving 2 levels of fertilizers (0, 40 kg NPK/ha) and 3 sources of soil were carried out to test their effects on cowpea. The growth parameters measured were plant height, number of leaves/plant and number of branches/plant. Number of nodules/plant, number of pods/plant, dry matter and grain yield were also estimated. Successive cropping of soils significantly reduced cowpea growth. Cowpea plants grown on soils from continuously cropped land had the least growth performance. Number of nodules/plant increased with successive cropping. Higher dry matter yield was obtained from the continuously cropped land. A significant (r = +0.55) positive correlation was found between soil P and dry matter yield of cowpea. NPK fertilization had only significant effect on plant height at 10 WAP but not on other growth parameters measured. The highest grain yield was obtained from unfertilized secondary bush fallow soil. Sources of soil (soil management system) had significant effect on some of the agronomic characters of cowpea
Mesocosm study of microalgae in different weather conditions
Get PDFMicroalgae have valuable contributions in carbon dioxide sequestration. There are no much investigations about motivation of mix microalgae productivity in outdoor cultures. This study aims to evaluate microalgae biomass production in outdoor mesocosms under different weather conditions. The experiment was done in Tilapia pond in the hatchery of fisheries of Universiti Putra Malaysia. Weather parameters were recorded daily. Microalgae seeds were obtained from Tilapia pond effluent and added to eight floating aerated mesocosms. Mesocosms were divided into four treatments. Two g triple supper phosphate: 20g Urea were used as fertilizers. Physical and chemical conditions, microalgae primary productivity and biomass, and species composition were measured every two days. Three cycles were categorized as mix, wet and dry cycles based on weather recording scores. Water quality parameters in Treatments and controls cultures showed significant variations. Primary production variables were higher in the fertilized non-sheltered mesocosms (treatment 1). Productivity variables were lower in the dry cycle and higher in the mix cycle. The highest value of fixed CO2 was (3.2) mg/L/d in treatment 1 in the mix cycle, while the lowest value was (0.11) mg/L/d in treatment 3 and control 1 in dry cycle. Changes in weather patterns are seen in the light and temperature values. Microalgae biomass was lower in dry weather conditions because of effect of high air temperature. Weather conditions and different treatments significantly influenced microalgae species composition, due to the sensitivity in some of them to different light intensities. Chlorophytes were the most abundant due to their ability to adapt with different culture conditions
Isolation of hexavalent chromium (VI) tolerant fungi from tannery effluent and their growth responses to different concentrations of chromium (VI)
Get PDFThe main objective of this study was to isolate, characterize, and determine chromium (VI) tolerance capacities of fungal strains from tannery effluent of the Kolkata Leather Complex area. Chromium (VI) is a heavy metal that is known to be toxic as well as carcinogenic. It is an important heavy metal widely used in various industries of which the tanning industry deserves special mention. The majority of Cr (VI) waste is discharged into the environment annually as a consequence of industrial and manufacturing activities. Kolkata Leather Complex is an industrial complex intended to serve as a central leather-tanning complex for Kolkata located at Bantala, near East Kolkata, India. Samples (tannery effluent) were collected in sterile capped tubes from Kolkata Leather Complex Area and brought to the laboratory for analysis. The samples were serially diluted and were plated on Czapekdox agar plates and incubated at 300C. After a few days, a number of morphologically different colonies were selected and sequentially subcultured for pure colony isolation on the same medium. They were preserved in the refrigerator at 40 C. Lactophenol cotton blue staining was done to observe and record the fungal morphological characteristics. They were further assessed for their hexavalent chromium tolerance capacities and subsequently the metal tolerance index was derived for each strain respectively. All 16 fungal strains isolated from the Kolkata Leather Complex tannery area were found to be chromium (VI) tolerant starting at 0.1mg/ml Cr (VI) concentration. Maximum chromium (VI) tolerance was displayed by sample S12 (2mg/ml) which was later identified as having 99.82% similarity with Aspergillus nomius strain.Keywords: effluent, fungi, heavy metal, isolation, hexavalent chromium, tannery, tolerance
Response of Ovalbumin to Fructose Addition and pH Variations - Ultrasonic and FTIR Study
Get PDFMain aim of this work is to understand how the protein ovalbumin is affected by the presence of cosolvent and variations in pH of the medium. The addition of cosolvent in many cases is found to control the extent of denaturation and pH is one of the main sources of denaturant of proteins. In this work, keeping fructose solution as cosolvent and pH of the solution as main variable, the extent of denaturation is analysed by ultrasonic methods and are further confirmed by FTIR amide-I second derivative spectra at 303 K. Obtained results shows that denaturation is sensitive to pH, however, acidic and alkaline behave totally in a different way. It was found that the impact of alkaline pH produces lesser denaturation and is slower whereas the impact of acidic pH is specific and instantaneous. Ultrasonic analysis shows that pH variation can denature the protein whereas the addition of cosolvent supports renaturation. FTIR spectra were recorded for the experimental samples from which the second derivative curve fitted spectra were constructed using Origin program. Quantitative assignment of peaks and the variations in cumulative areas calculated for the structures like α-helix, β-sheets etc confirms the observations of ultrasonic analysis that the pH variations aid in denaturation whereas the cosolvent supports the renaturation of protein.
Impacts of Controlled Forest Fires on Soil Properties in Gadchiroli Forest Circle, Central India
Get PDFForest is an important ecosystem service to human beings. In recent decades the forest is facing tremendous pressure from anthropogenic activities. One of the activities is the burning of forest floor for easy collection of non-timber forest produce. As a result of this number of incidences of forest fires has increased in the tribal-dominated area of the world. These forest fires have adverse impacts on soil properties which will ultimately in the long term have impacts on the forest ecosystem. Taking into consideration this fact this study was attempted to assess the impacts of controlled forest fires on the physicochemical properties of forest soil in the Gadchiroli forest circle of Central India. To assess the impacts six sampling sites from the forest where identified from the study area where no previous forest fire history was recorded in that season. Initial soil sampling before controlled forest fire was carried out in summer 2019 by quartering method in the topsoil layer (1-5 cm). A controlled forest fire was carried out in the same area. The soil was prepared for soil analysis and analysed by adopting standard methods for bulk density, water holding capacity, pH, electrical conductivity, organic carbon, and organic matter. Results revealed that forest fires increase the bulk density of soil, at 50% (n = 3) sampling locations water holding capacity got reduced down; whereas, at other half increased in capacity was observed. In the case of soil pH 66% (n = 4) sample reported increased in soil pH and at other reduction in soil pH was recorded. Except at one sampling location electrical conductivity was reduced. A similar trend was also noticed for organic carbon and organic matter. Bulk density and water holding capacity will have long term impacts; whereas, pH, electrical conductivity, organic carbon and organic matter will have short term impacts. Furthermore, in those sampling locations where forest fire does not occur in the last 2-3 years organic carbon and organic matter content of the soil is high. Thus, measures to be taken to reduce forest fires activities by incorporating an effective forest fire management system at a place by incorporating fire load management subsystem and fire suppression subsystem.
Use of two green algae Ulva lactuca and Ulva intestinalis as bio-fertilizers
No full textIn recent years, development have been witnessed in the market expansion of agricultural inputs and products including substances and materials that improve the functioning of soil, plants and the interactions between soil and plant. This is a very broad category of products and substances that often bring innovative solutions in the field of fertilization and crop protection.The objective of this study is to improve the production of market garden where tomato plants in nurseries from powders of two green algae Ulva lactuca and Ulva intestinalis, harvested as bio-fertilizers in the west coast of Mostaganem province. They have minimal effects on the environment, including soil, subterranean water, River and Estuary ecosystems such as Cheliff River, biodiversity and global warming.The experimental part was carried out following the method of extraction of algae and used as a bio-fertilizer on tomato to its simplicity and accuracy, which is the subject of the study of the germination, growth and the development of young plants.The results of this study showed that algal powder of Ulva lactuca and Ulva intestinalis exhibit a remarkable stimulatory effect on the cultivation of tomato, which aims to improve their production, and evident when compared to controls setup. Keywords: seaweed, Mostaganem, River Ecosystem, eco-agriculture, smart agriculture, bio-fertilizers, tomato
Effect of fortification of Pasta with natural immune booster Moringa Oleifera leaves powder (MLP) on Cooking Quality and Sensory analysis
Get PDFMalnutrition is a worldwide escalating severe problem, impacting majority of the Indian population. Currently, it is difficult to meet, the nutritional requirements with a limited type of stored food as compared to the variety of freshly available food. In such a scenario incorporating, the immune-boosting nutritional ingredients in a commonly consumed food can be adopted as one of the nutritional approaches. Hence, as an alternate to fresh food, the usage of a fortified high-nutrient food products can be one of the approaches e.g., the inclusion of fortified pasta in meals. Moringa oleifera is a fast-growing underutilized tree with high nutritional value. Its leaves are rich sources of bioactive components, vitamin A, vitamin C and Iron. Fortification of pasta products with Moringa oleifera leaf powder can be one of the cost-effective approaches and, a best immunity booster supplement for enhancing the nutritional value of pasta-based products which can be stored for several months. In current study, the preparation of pasta fortified with varying concentrations of Moringa oleifera leaf powder (MLP) was attempted, followed by its cooking quality analysis (cooking time, cooking weight, cooking loss and water absorption) and sensory attributes evaluation (based on 9 points hedonic scale including the colour, taste, texture, flavour and overall acceptability). The results from the qualitative as well as quantitative analysis suggest that the fortification of pasta with Moringa oleifera leaves differentially modified the sensory characteristics of the pasta in a concentration-dependent manner. The present study indicates that the fortification of pasta with Moringa oleifera leaf powder can act as a natural immune booster, and has the potential to reduce the probability of microbial infections.
Keywords: Bioactive Components, Fortification, Moringa oleifera, Pasta
Effectiveness of university-based extension outreach for maize production in southwestern Nigeria
Get PDFThe study was conducted with the purpose of assessing the effectiveness of maize management practices by University-based extension outreach (UBEO) in southwestern Nigeria. 165 outreach beneficiaries were interviewed for the study via structured and pre-tested interview schedule, in the two purposively selected UBEOs using a multistage sampling technique. Data collected were analyzed using descriptive statistical tools such as frequency counts, percentage, mean and standard deviation while inferential statistics such as Chi Square and Pearson Product Moment Correlation were used to test the hypotheses. The mean age of the respondents was 52.4±19.8 and their maize farming experience was 16.4±13.6. Besides, the mean of years in formal education of beneficiaries was 7.4±4.6. Also, 75.6 percent got information about the outreach through their community leaders and they participated to better their lot in life. Many (51.2%) of the respondents have been benefiting for the past 10 years. Besides, maize management practices by UBEOs were appropriate land preparation, seed selection, timely planting and appropriate seed rate among others. The maize yields before and after the management practices were 3.4±1.3 and 4.2±2.1 tons/ hectare respectively, and majority (92.3%) of the maize farmers indicated that the management practices by UBEOs were effective in improving the yield. The findings revealed that at p<0.01, reasons for participation (χ2=31.612) of the respondents had significant association with effectiveness of production technologies. Furthermore, at p<0.01, farming experience (r= 0.503) and years as beneficiaries (r= 0.501) had significant relationship with effectiveness of the management practices; also at p<0.05, age (r=0.322) and years of formal education (r=0.389) of respondents had significant relationship with effectiveness of the management practices. The study concludes that the maize management practices by UBEOs in the study area were effective in improving the capabilities of the beneficiaries. It was recommended that UBEOs be sustained and expanded to cover more rural communities.
Keywords: Effectiveness, management practices, university-based extension outreache