Archives Issues
Volume 12, Issue No 3, Sep 2013
Research on Building Wind Environment Based on the Comparison of Wind Tunnel Experiments and Numerical Simulations
With the continuous development of computer, computer numerical simulation is widely applied. In this paper, a combination of experimental and theoretical analysis, wind tunnel experiments and numerical simulation results are compared. It is anchored to the architectural wind environmental studies, explored the relationship between the environment and the building and the role of the environment on the building development, and the impact of the wind environment on the architectural design and the structural design, in order to restore the positive interactions between the environment and the building, and lay the foundation for the road to the sustainable development of the building.
Li Yang
Characterization and Valuation of the Domestic Solid Waste of Fidjrosse District in Cotonou (Republic of Benin) by Aerobic Composting
This work proceeded in Fidjrossè district in Cotonou from November 2009 to December 2010. It consisted with a field investigation, with the characterization of the urban solid waste collected in this district, with valorisation by aerobic composting of the fermentable fraction of the waste. From work of investigation it arises that 25 % of households continue to throw their faeces on wild dumps while 13.33 % continue to make the incineration. 81. 67% of the surveyed households have a daily production of waste lower than 1 kg. The characterization of collected waste records in mass 50.19% of biodegradable matters; fine sand 32.18%; 0.63% of shells, carapaces of crabs and pearls; 0.13% of engraved and pieces of brick; 8.31% of plastics; 4% of paperboard; 1.58% of metal; 1.11% of textile and debris of mattress; 1.01% of glasses; 0.79 of shoes and leathers; 0.7% of used batteries; 75% of moisture for the fermentable fraction. On the whole, 262kg of fermentable waste was composted with an output of 65, 67% which is approximately 172kg of ripe compost. The physico-chemical characteristics of the compost obtained give inter alia values a report of ratio C/N of 11.69% and one rate of total phosphorus 0.062%. The real-mould of our compost has a heavy CEC and holds the nutritive mineral ions as the cations K+ and Ca2+ and phosphate so as to make available for plants for their growth and to improve the soil fertility of the site as well as its increased need for organic soil conditioner.
Cyrille Tchakpa, Patrick A. Edorh, Patient Guedenon and Michel Boko
Investigation of the Removal Efficiency of Foulants by Anoxic/Aerobic Membrane Bioreactor Treating Pickle Wastewater
Pickle wastewater was treated by anoxic/aerobic membrane bioreactor. Three groups of experiments were designed under the condition of different feed loadings to research on treating pickle wastewater by mixed MBR with PVDF. In the case of normal temperature, the salinity was 2-3%, the bio-film density was 15% in both of the anoxic and aerobic zones; DO was 1mg/L and MLSS was 2000 mg/L in the anoxic zone; DO was 4-5mg/L and MLSS was 6000 mg/L in the aerobic zone. The ratio of the recycling mixture was 200%; the sorption pumps were turned off for 3 minutes in every 10minutes; the pressure gradient was 15KPa. According to the study of removal efficiencies of organic pollutant, it indicates that when the feed loading is 1.2 kgCOD/(m3.d), the removal efficiency is optimal. And the effluent concentrations of COD, NH4+-N and SS satisfy the requirement of the first class discharge standard of comprehensive discharge standard of sewage (GB8978-1996).
Hongxiang Chai and Shen Li
Adsorption of Reactive Blue and Direct Red Dyes on Powdered Activated Carbon (PAC) - Equilibrium, Kinetics and Thermodynamic Studies
The present study deals with the adsorptive removal of Reactive Blue 19 (RB19) and Direct Red 81(DR81) from their aqueous solutions. Powdered Activated Carbon (PAC) was used as an adsorbent. Batch studies were performed to analyse various experimental parameters like adsorbent dose, pH, contact time and initial dye concentration. Optimum PAC doses for RB19 and DR81 were found to be 0.2 g/L and 0.3 g/L, respectively. Effective pH for RB19 and DR81 removal was found to be 2 and 7, respectively. In addition, high percent removal with decrease in initial dye concentration was observed. Quasi-equilibrium was attained in 3h for both dyes. Pseudo-second-order rate equation satisfactorily represented the adsorption kinetics for both the dyes. Langmuir and Temkin isotherms were found to best represent the equilibrium data for DR 81-PAC system whereas for RB19-PAC system Langmuir isotherm was found to be best suited. Furthermore, thermodynamic studies showed that the adsorption of both the dyes onto PAC was exothermic in nature.
Parul Bhatt, Raj K. Vyas, Prabhat Pandit and Manisha Sharma
Study on the Changing Law of Dissolved Oxygen and Dissolved Oxygen Saturation in Baiyang Lake
We studied the changing laws of dissolved oxygen (DO) and dissolved oxygen saturation of Baiyang Lake in the past few years. The analysis of dissolved oxygen was from two angles, they were monitoring value and saturability. The results showed that concentration of dissolved oxygen in Baiyang Lake was between 4.08 mg/L and 15.00mg/L, and concentration of dissolved oxygen in a day with the changes of light intensity showed a strong regularity, it was identical in changes of photosynthesis of aquatic plants. The volatility of changes of dissolved oxygen in summer and autumn were more than in spring and winter. The average values of dissolved oxygen were greater in winter than in spring and greater than in autumn and greater than in summer. This was related to water temperature, biomass and biological activities of lives. Dissolved oxygen saturabilities were close to 100% in spring and summer, so photosynthesis was stronger than oxidation in water. Dissolved oxygen saturabilities in autumn and winter nevertheless were less than 100%, and oxidation in water was in a dominate place. Following the comprehensive analysis, dissolved oxygen in Baiyang Lake was mainly affected by temperature, organic matter concentration and water-plants. The characteristics of photosynthesis were obvious in spring and summer and the oxidation in autumn and winter were obvious.
Jianwei Ma, Junliang Liu and Shuxuan Liang
Levels of Accumulation and Release Mechanism of Pollutants in Sediments of Lihe River as a Water Conveyance Canal
Lihe River as an important water conveyance canal of diversion project from Luanhe River to Tianjin should convey 40-50 m3/s water in each spring and autumn. With the variation of water discharge, the sediments with poor viscosity and great suspension capability were very prone to re-suspension and pollutants release easily. In order to study the effects of pollutants release in sediments on river during water diversion period and set out proper protection scheme to prevent the second pollution, experiments were done to make clear the levels of accumulation and release mechanism of pollutants in sediments. First, compared with those in Haihe River, Wulihu Lake and Xuanwuhu Lake, the average content of organic matters of sediments in Lihe River was 0.21%, lower obviously, TP with the average value of 5.18 mg/kg was much higher, while TN reaching 2.99 mg/kg, a little higher than others. Second, water diversion indeed made pollutants in sediments release quickly and threaten water quality seriously. TN was the main pollutant, a high level in both river and sediments, which kept releasing with the maximum release amount of 9.16 g/m2 and intensity 4.2 g/m2/d and had a great negative influence. TP and Fe with the maximum release amounts were 0.248 g/m2 and 1.7 g/m2 with maximum release intensities of 0.248 g/m2/d and 1.7 g/m2/d respectively. They released fast and deposited also fast, and were the potential pollutants and the release amounts could not be neglected during the initial water diversion period.
Liqin Zhu, Cuiling Jiang, Youheng Wang, Yanmei Peng and Peng Zhang
Comparative Study on the Modelling of Mixing Length Distribution in the Sediment-Laden Flow
In view of the established mixing length model with lack of outside China applicability, different forms of flow must be adopted. Firstly, from motion mechanism of mixing-length of the sediment-laden flow, a new mixing-length distribution mode in vertical was deduced by combining flow turbulence theory with applied mathematics theory. Then, the existing typical experimental data were verified well, and by comparing linear distribution and parabolic distribution, the result shows that the distribution is superior to the latter two. Finally, its dynamics lead to mixing-length distribution characteristic is also discussed preliminarily, and influence of the sediment concentration on the distribution of the mixing-length. The established expression on the vertical distribution of the mixing-length is not only simple and explicit, but also better reflects the motion characteristics of the complex flow, for the foundation of further study on the velocity profile of the sediment flow.
Ni Zhihui, Wu Lichun, Zhang Xujin, Yi Jing and Zeng Qiang
Environment and Sustainable Development: A Study Among the Tribes of Eastern Ghats in Andhra Paradesh
This paper provides the existing interrelationship between environment and sustainable development. In addition to this, it discusses about tribal ecology, livelihoods of tribes, issue of shifting cultivation and deforestation, Indigenous knowledge of tribals in protection, conservation and regeneration of natural resources and strategies for sustainable development of tribes in Eastern Ghats of Andhra Pradesh specific and other tribal areas, in general. All these aspects in the paper are explained with the evidence of an empirical case study of Eastern Ghats forest environment of A. P. in which around 27 hill tribes inhabits. These tribes are distributed in the tribal sub-plan areas of Visakhapatnam, Srikakulam, Vizianagaram, East Godavari, West Godavari, Khammam, Mahaboob Nagar and Warangal districts of Andhra Pradesh. The paper comprises of both semantic and scientific explanations with ethnographic methodological descriptions. This paper forms the part of a Major Research Project Report “Environment and Sustainable Development : An Anthropological Study Among Tribes of Eastern Ghats in Andhra Pradesh” sponsored by I.C.S.S.R., New Delhi.
V. Subramanyam and B. Veerabhadrudu
Study on the Properties of Calcined Waste Mussel Shell
Mussel shell has been calcined on high temperature. Its main component calcium carbonate is decomposed into CO2 and calcium oxide. Calcium oxide is superbase catalyst for the transesterification reaction. By means of differential thermal balance, the decomposition characteristics of mussel shell have been studied. And of electron microscope, TEM shows grain morphology characteristics of calcination at different calcining temperatures. Organic matter has decomposed during 287°C-458°C. Decomposition of calcium carbonate starts from 600°C to 800°C, when it was balanced. By use of orthogonal analysis, the main influence factors of specific surface area have been optimized. The optimal process parameters are 950°C calcination temperature, 120ìm initial diameter and 1 hour holding time.
Yijun Zhang, Shengyong Liu and Peiran Chen
A Comparative Study on the Presence of Halophilic Vibrios in Edible Oyster, Crassostrea madrasensis from the Backwaters of Chennai Coast
Vibrios contribute the major part among water and foodborne pathogens in coastal ecosystems. The members of the family Vibrionaceae contribute 60% of the total bacterial population. The current work is aimed at the analysis of the presences of Vibrio species in edible oyster Crassostrea madrasensis along the coastal line of Chennai in Ennore, Royapuram and Muttukadu. The oysters were collected, and total heterotrophic bacteria were analysed using selective non-selective agar medium and further confirmed by biochemical tests. The predominant pathogenic halophilic Vibrio species were identified to generic level according to Bergey’s Manual of Systematic Bacteriology. Among the Vibrios, Vibrio alginolyticus, V. parahaemolyticus and V. harveyi were the dominant species identified in Crassostrea madrasensis.
C. Ganga Baheerathi and K. Revathi
Performance Evaluation of Eco-friendly Green Concrete
This study was aimed to minimize the use of natural river sand which is being used for several years in construction, and to utilize bottom ash from thermal power station as a partial replacement (30%, 60%, 100%) for fine aggregate. An experimental investigation has been carried out to find the compressive strength of the replaced eco-friendly green concrete with different curing methods. An equation recommended by ACI committee for conventional concrete was used to predict 56, 90 and 180 days compressive strength from 28 days compressive strength of the eco-friendly green (bottom ash) concrete that resulted with the difference between the experimental and predicted compressive strength to ± 12%. To minimize the percentage of difference, an empirical relationship was developed between the compressive strength of accelerated curing and normal curing (28, 56, 90, 180 days). It is concluded that empirical relationship predicts later age compressive strength with the minimum percentage of difference. This study of predicting later age compressive strength from empirical relationship will ultimately save time, material and most importantly assessing the quality of the design of construction.
A. Arun Kumar, A. S. Santhi and G. Mohan Ganesh
Resource Utilization of Returned Rapeseed Straw and Its Effect on Soil Fertility and Crop Yields
In order to study the decomposition characteristics of returned rapeseed straw in the process of resource utilization and the effect on soil fertility and crop yields, different treatments of soil with returned rapeseed straw were conducted using the nylon net bag method of field trials. Different treatments include varied amounts of straw, depths to be buried in soil, and addition of straw decomposing bacteria. The results showed that the decomposition ratio of rapeseed straw increased with time and the decomposition rate of rapeseed straw was faster in the first 30 days and then slowed down until the end of 120 days. Straw decomposition rate was negatively correlated with the amounts of returned rapeseed straw. The decomposition rate of rapeseed straw on the soil surface was faster than that buried 20cm below the soil surface, which is also faster than that 10cm below the soil surface. Decomposition ratio of rapeseed straw with addition of decomposing bacteria was higher than without decomposing bacteria. The returned straw improved the physical and chemical properties of soil and increased the soil nutrient content and rice yields. The study provided the basic parameters for controlling the rapeseed straw decomposition rate, which improved the agricultural eco-environment.
Hu Hong-xiang, Ma You-hua, Wang Yu-fang and Di Yun-fei
Relationship Analysis Between Cultivated Land Resource Change and Economic Growth: A Case Study in Sichuan Province, China
Based on the statistics in Sichuan province during 1978-2010, the dynamic process of cultivated land area change and economic growth was analysed firstly. And then, the regression model between cultivated land area and pre capita GDP was established. At last, the cultivated land area under different levels of economic growth was predicted according to the established regression model. The results were that the cultivated land area in Sichuan province showed the decreased trend and the decreased trend can be divided into three phases, slowly decreasing phase, drastically decreasing phase and eased phase, in the past 33 years. The cultivated land area and pre capita GDP were negatively correlated and the correlation equation was a logarithmic decreasing function in Sichuan province. With the gradual increase of the per capita GDP, the cultivated land area will decrease slowly in the future, but the decreasing trend may be stabilized. Combined with the development status of Sichuan province, the results indicated that the contraction between the cultivated land area and pre capita GDP can be mitigated or even eliminated with scientific land management strategy, input increase and technological transformation. On the basis of the study, the protection suggestions were proposed from the point of view of avoiding occupation and degradation of cultivated land.
Liangqian Fan, Fenghui Chen*, and Hongbing Luo
Spatio-Temporal Variations of Urban NO2 Concentrations in China
The spatial and temporal characteristics of NO2 concentration were analysed from 31 cities in China over a six-year period (2003-2008). Urban NO2 concentrations were in the range of 12-73µg/m3, and its pollution levels had an expanding trend in the temporal variations during 2003-2008. Spatially, there was an evident difference for urban NO2 concentration in the three regions of the eastern, central and western China. NO2 concentrations in cities had a significant reduction in eastern China, an obviously heightened trend in central China and a small heightened trend in western China due to the combined effects of industrial structural transformation and industrial upgrading, as well as control measures.
Fangshu Gao, Ying Peng, Guoxiang Wang and Yi Qian
Pesticide Exposure and Cancers in Barpeta District, Assam - A Case for Control Study
Occupational exposure of carcinogenic pesticides in agricultural fields of Barpeta district, Lower Assam, is a matter of concern. The aim of this study is to investigate the relationship between exposures of carcinogenic pesticides and occurrence of cancer in the agricultural region of Barpeta district. A structured questionnaire was employed in a field based case-control study to gather information on demographics, occupation, pesticide exposure, agricultural practices, family history and medical history along with smoking habit. One hundred cases of different cancers were identified in the field. The control (100) were chosen from the same environment in terms of age, sex, smoking and other food habit. To control confounders, multiple logistic regression analysis was used. To assess the dose-respond relationship between exposure and disease, the chi-square test for trend was used. One hundred (100) historically confirmed cancer cases were detected from the year 2008-2010. Sex and age matched one hundred controls were included in the study. Pesticide exposure independently associated with different types of cancer in the region. Lung cancer (OR = 1.138, 0.790-1.48, P = 0.769), Throat cancer (OR = 1.426, 0.564-3.78, P = 0.735), leukaemia (OR =1.167, 0.261-5.909, P = 0.056), stomach cancer (OR = 1.069, 0.281-4.385, P = 1.00). Pesticide exposure strongly associated with cancer after controlling smoking. Cancer was associated with pesticide exposure after controlling the confounders. Smoking and eating during pesticide application were identified as modifying factors for increasing the risk of cancer. The poor pesticide work practices identified during this study. Proper training and educational campaigns are essential for handling pesticides.
M. Hazarika and R. Hazarika
Study on Management of Sugar Cane Industry Solid Waste Using the Technique of Composting
Sugar industries play a pivotal role to improve the economy of our country. For the management of sugar industry solid waste (press mud and bagasse) an effort was taken. The press mud and bagasse mixed with garden waste and cow dung were subjected to the process of a composting (anaerobic decomposition) in 1:1:2 ratio. One set of component was moistened with water (A) and another one was moistened with spent wash (B). As spent wash is characterized with high BOD and COD along with high nitrate, phosphate, potassium and other minerals, it was selected for moistening the organic waste. After the experimental period (95 days) the reduction of organic matter and C:N ratio was considerable. The amount of N,P,K in compost A was found to be 2.4%, 0.71% and 2.14% respectively. The N.P.K value of compost B was found to be 2.8%, 0.85% and 3.59% respectively. All these nutrients have considerably increased in compost B than compost A. The C:N ratio of both the composts was around 11:1, which has been reduced from the initial of 25:1 ratio. The identified organisms Pseudomonas sp., Streptococcus sp., Bacillus sp. and Klebsiella sp. were involved in the composting process of A. Besides these organisms, compost B also has Seratia sp. Hence, from these observations, it is clear that the press mud and bagasse in combination with garden waste and cow dung may be utilized for the production of compost successfully. This technique further minimizes the environmental hazards that could have been caused by press mud and spent wash if they were disposed off as such in the environment.
C. Thamaraiselvi and M. Vasanthy
Removal of Hexavalent Chromium from Aqueous Solution by Adsorption on Raw Powder and Chemically Activated Carbon of Hibiscus rosa-sinensis Flowers
Adsorption using low cost adsorbents is one of the cheapest methods that can be used for removal of hexavalent chromium from water. In this study, a comparison has been carried out on adsorption using raw Hibiscus rosa-sinensis flowers and activated carbon prepared by impregnation of the Hibiscus rosa-sinensis flower. Hibiscus rosa-sinensis flowers are low cost adsorbents available throughout the year and easily biodegradable, and hence cost effective. Impregnation of the flower powder with different ratios of sulphuric acid was carried out. Adsorption using carbon is found to be more efficient as compared to the raw flowers. The optimum adsorbent dosage for the carbon was found to be 200mg/100mL, and for the raw flower 400mg/100mL. Both, Langmuir and Freudlich isotherms were studied and from the values of coefficient of determination obtained, it was concluded that the Langmuir isotherm fits well. Kinetic studies were also conducted. This included the pseudo first order and pseudo second order kinetics. The qe,cal values obtained for pseudo first order kinetics for the carbon and raw flower were 7.799 mg/g and 29.459mg/g respectively. This showed a large variation from the experimental value. But for the pseudo second order kinetics only a slight variation from the experimental value was observed. Hence, it was concluded that the adsorption process followed pseudo second order kinetics.
Renny Mariam Mathew, M. Arthy, M. P. Saravanakumar and C. Balamurali Krishna
Recovery of Nutrients from Wastewater by Struvite Crystallization
Discharge of untreated domestic wastewater often leads to eutrophication of receiving water body and create a septic condition, and accelerate sewage sickness in case of land-disposal. However, since domestic wastewater is recognized as nutrient rich water, the recovery of nutrients using a chemical precipitation and crystallization technique may provide value added product struvite, which is a slow releasing fertilizer. This research work shows the techno-feasibility struvite precipitation as an attempt for improving water quality, with simultaneous recovery of struvite as byproduct.
Ajit Kumar, Ashutosh Das, Mukesh Goel, K. Ravi Kumar, B. Subramanyam and J. S. Sudarsan
Seasonal Variations of Heavy Metal Distribution in Waters and Green Mussels of Ennore and Royapuram Estuaries, Tamilnadu, India
The objective of this study is to comparatively analyse and assess the heavy metal pollution in coastal areas of Ennore and Royapuram, Tamilnadu, India. Ennore coast receives untreated/treated effluents from Manali Industrial belt, which houses many chemical Industries. Royapuram mainly receives domestic sewage. Analyses of water and mussel samples were done by ICP-AES. During summer all the dissolved heavy metals exhibited maximum values. The result shows that concentrations of copper, cadmium, zinc and lead were above the permissible limits.
V. Gayathri and K. Revathi
Comparative Study of the Quality of Bottled Drinking Water Called Kawthar from Some Commercial Treatment Plants in Taiz City, Yemen
Water supply in Taiz city contains high concentration of different elements so it is not suitable for drinking purpose, therefore, the people in the city depend upon commercial water from different units of water treatment. This type of water is commonly called Kawthar. Water quality with regards to pH, Cl2, HCO3, hardness, Ca, Mg, NO3, TS, TASA (total anions of strong acids), coliform group and E. coli was tested. There were variations in some physico-chemical characteristics in the samples but the concentration of these parameters was within the permissible limit of WHO. The reason for this is that all waters used for the treatment were brought from groundwater of good quality from outside the city. Bacterial parameters did not show any growth in coliform group and E. coli and in MPN test show results within the permissible limit, except in K7 and K8 samples. Relation among water quality parameters reveals a significant positive correlation between pH and TASA, TS, SO4 and hardness. Total hardness shows a positive correlation with TS. SO4 shows a positive correlation with TASA.
Wadie Ahmed Al-Shargabi and Raya Al-Ansi
A Finite Difference Model on Atmospheric Pollution and its Application
In view of near-ground atmospheric problem, near-ground atmospheric pollution model was established. Because the applicability of analytical solutions is extremely limited for such conditions, and the distribution and transport of pollutants in air are controlled by geographical conditions, numerical techniques are essential for air pollution modelling. In this paper, finite differential method is used to establish plane two-dimensional numerical model of near-ground atmospheric pollution belt, and truncation errors associated with finite-difference solution of atmospheric pollution were corrected based on the Taylor analysis. The results indicate that this method provides the references for the forecast of pollutants and the management and evaluation of air resources.
Changjun Zhu, Ming Liu and Wenlong Hao
Fuzzy Evaluation and Analysis of Surface Water
The comprehensive evaluation of the monitoring data of surface water in Handan City, based on the model of fuzzy comprehensive evaluation, was made in this paper. According to the monitoring data, selecting seven evaluation factors, namely, permanganate index, BOD, total nitrogen, total phosphorus, ammonia, fluoride and dissolved oxygen, weight matrix has been established for each factor, and the weight of each factor was obtained in the assessment of water quality. Then using the membership function in fuzzy mathematics, computed the data measured, and obtained the corresponding water level. The result of the evaluation shows that the water quality of Handan city is V level, severely polluted, and it becomes a security risk to the residents’ drinking water. Besides, it can be used as the scientific basis for water quality control.
Jihong Zhou, Yuanzhi Li and Xumin Tian
Effects of Forest Communities and Various Depths on Soil Enzyme Activities in the Hyrcanian Forest
Detailed information on soil quality can be ascertained by measuring soil enzymatic activities, which are often affected by soil biological chemical processes and depth. This study investigates the activity of four enzymes, acid phosphatase, alkaline phosphatase, urease and dehydrogenase in three various tree communities; Parrotio-Fagetum, Parrotio-Carpinetum, and Parrotietum at 0-20 cm depth with and without rhizosphere and 20-40 cm depth in the Kheyrud forest, Northern Iran. We found the higher enzyme activities in rhizosphere than without rhizosphere in all the communities. Soil enzyme activities decreased with increasing soil depths. There was a significant difference in acid phosphatase between 0-20 cm without rhizosphere and 20-40 cm. These findings were attributed to the observation that root propagation was reduced across the depths. Alkaline phosphatase and dehydrogenase, both showed a significant difference in activity among the communities, but acid phosphatase and urease did not. Microorganisms producing alkaline phosphatase and dehydrogenase were found to be significantly affected by the vegetation. Alkaline phosphatase activity in both depths and dehydrogenase at 0-20 cm with and without rhizosphere were greater in Parrotietum than those of Parrotio-Fagetum and Parrotio-Carpinetum. It appeared that the microbial community in Parrotietum was much greater than the other two types.
Sima Bargrizan, Mohammad Matinizadeh and Anoushirvan Shirvany
Water Quality Modelling of a Stretch of River Kshipra (India)
River Kshipra is receiving a large volume of untreated sewage daily in its stretch of Ujjain city and the status of water is pathetic during low flow season. A stream water quality model QUAL-2Kw was used in the present study to simulate the contributions from different sources and sinks of dissolved oxygen and to understand the interactions among them. The model was calibrated and validated and the simulated results are in general agreement with measured water quality in River Kshipra. It was established through this study that the QUAL-2Kw model can be used for future river water quality management options for River Kshipra with reasonable accuracy.
R. C. Gupta, Ajay K. Gupta and R .K. Shrivastava
Photocatalytic Degradation of Hazardous Dye Acridine Orange Using Semiconductor Titanium Dioxide (TiO2) Under Visible Light
Inordinate population growth and advanced technological development, at one hand bettered the life of human and on the other hand it is greatly damaging the environment. In the present work the study of hazardous synthetic dyes, especially used in textile and leather industries, has been carried out. These dyes in wastewater are principal cause of pollution in water bodies of human use. The most effective decomposition of Acridine Orange dye was observed with catalyst amount 300 mg/100 mL with 3.8 × 10-5 mole dm-3 initial dye concentration at pH 9. The rate of reaction increases as the concentration of H2O2 increases and reaches the optimum at 9 × 10-6 mole dm-3. As the irradiation time increased, dye molecules got degraded and the estimated COD value decreases from 184 mg/L to 0 mg/L, and CO2 value increases from 55 mg/L to 242 mg/L in 6 hours of illumination.
David Swami and Pramod Pandit
Toxic Effects of Aluminium and Fluoride on Planktonic Community of the Microcosms
Aluminium and fluoride were found toxic to phytoplankton, periphyton and zooplankton in the microcosms raised in the greenhouse. The toxicity of aluminium was relatively higher than fluoride, more particularly, during winter season. There were significant reduction in counts of phytoplankton (49-80%), periphyton (algae = 40-68%, zooplankton = 35-75%) and zooplankton (5-77%) in the treatments in comparison to controls. As a result, Reciprocal Simpson index, Equitability index and Shannon-Weiner index decreased. Such changes will affect energy flow in the microcosms.
Neha Upreti, Shweta Sharma, Subhasini Sharma and K. P. Sharma
Strategic Environmental Assessment of the Coal Industry
The application of strategic environmental assessment of coal industry to improve industrial environment and adjust industrial structure is urgently needed. First, a combination of practical situations of coal industry and theory-based dynamic method of strategic environmental assessment, would enable a further development of related strategic environmental assessment that could be applied more effectively when deals with coal industry in practice. Second, based on modern ecological theory, strategic environmental assessment could help reveal the influence of coal industry on ecological and environmental aspects and associated mechanisms. Third, strategic environmental assessment, as well as traditional prevention and control research, could be used as indicators of the development trend of coal industry. Our results showed that when strategic environmental assessment was applied to coal industry, it could provide a strong methodology guidance and help reveal potential mechanisms. On the other hand, from the perspective of model ecological theory, strategic environmental assessment could reflect the applicability and feasibility of related theories in practice.
Qian Hong-wei and Yin Xiang-ju
Heavy Metals in Deep Seated Groundwater in Northern Anhui Province, China: Quality and Background
Forty-five deep seated groundwater samples from three aquifers in two coal mines (Wolonghu and Baishan), northern Anhui Province, China have been measured for four kinds of heavy metal (Pb, Zn, Cr and Ni) concentrations for evaluation of quality and, establishment of environmental background values by using model based objective methods. The results suggest that these groundwater samples are of excellent quality relative to the quality standard of groundwater established by Chinese government, and most of them can be used for drinking directly according to their low concentrations of heavy metals. Moreover, they are considered to be representative of “pristine” state because they are far away from anthropogenic contribution and therefore, they can be used for environmental background estimation. The thresholds of Pb, Zn, Cr and Ni between natural and abnormal or anthropogenic are calculated to be 17.4, 64.9, 3.9 and 71.1mg/L by using model based objective methods, respectively.
Linhua Sun, Herong Gui, Weihua Peng and Manli Lin
Study on the Technology of Vortex Clarification and its Application in Wastewater Treatment
After a brief introduction to the core parts of vortex coagulation technology, like the characteristics of vortex reactor, and its working mechanism with contact-flocculation and vortex coagulation, this paper emphasizes that the critical point of the vortex clarification technology is the micro vortex coagulation. Also it tells us the application of clarification tank in wastewater reuse plant. After alteration of the standard clarification tank in which the micro vortex reactor has been put into the first and second flocculation areas and the inclined pipes into the sedimentation area, the treatment scale of the vortex clarification tank is increased, and the effluent turbidity of the tank is lower than 3 NTU, the effluent turbidity of finished water is lower than 1 NTU and the investment of per ton micro-vortex water is lower than 50 Yuan RMB. The paper argues that in comparison to other coagulation reactors, micro vortex reactor deserves wide application for its various advantages, such as its higher coagulation efficiency, shorter reactivity time, better quality of finished water, stronger adaptive capability, and more conveniences in construction and the like.
Tong Zhengong
Effects of Planting Patterns on Leaf Area Index, Ground Dry Matter and Yield of Summer Maize
In order to probe the influence of different ridge tillage planting mode of summer maize, the study has been conducted on leaf area index, ground dry matter accumulation and yield of contrast. The results indicate that in the whole growth period of summer maize, leaf area index of ridge tillage cultivation is increased relative to that in traditional flat cultivation. The maximum difference is 0.43. Leaf area index of trapezoidal ridge tillage cultivation is higher than that of V-ridge, with the biggest difference of 0.23. Ground dry matter accumulation and yield of ridge tillage cultivation are higher than traditional flatten culture, and the planting mode of trapezoidal ridge tillage is better than V-ridge tillage. On the basis of the experimental results, it is suggested that the trapezoid ridge tillage planting of summer corn is suitable to extend widely in the western region of China.
Shun Sheng Wang, Chuan Chang Gao and Xing Wang
Biodiversity of Algal Flora in River Chambal at Kota, Rajasthan
Phytoplankton, represented mainly by algae, form a significant part of the food web and, therefore, information on their population is important in wetland management. Phytoplankton are very sensitive to any environmental change since they quickly response to any alteration or changes in the environment. The plankton population observation or biological analysis is reliable tool for biomonitoring to assess the status and quality of aquatic bodies. The present study is aimed to determine the algal diversity and quality of water in Chambal river at Kota, Rajasthan. The algal and water samples were collected at monthly intervals from different areas located in upstream and downstream of the River Chambal. In the present study Palmer’s biotic index has been used to assess the quality of water. The algal flora of four sites of river revealed 70 species belonging to four classes.
Meera Bhatnagar and Nilima Bhardwaj
Analysis of Fluoride Ion Concentration From Salt Pans of Marakkanam, Villupuram District, Tamil Nadu
Fluorine is an important trace element that forms fluoride compounds. Fluoride as salt is known for both positive and negative effects on human health. Deficiency of fluoride leads to dental caries and excess causes a severe disease called fluorosis. Intake of fluoride rich food is also responsible for fluorosis. WHO recommendation for the permissible limit of fluoride is 1.5 mg/L. The saline water and salt samples collected from Marakkanam, Villupuram District were studied with special reference to the fluoride content. The samples were drawn in the pre-monsoon period comprising eight days during May 2011. The findings revealed that the concentration of fluoride was between 0.9 mg/L and 1.4 mg/L, which is within the permissible limits. The concentration of fluoride ion increased in the salt water till the start of crystallization, which subsequently decreased with an increase in salt formation.
R. Sundarakumar and S. Ponnusamy
Volumes & Issues
- Vol 23, No 1, Mar 2024
- Vol 22, No 4, Dec 2023
- Vol 22, No 3, Sep 2023
- Vol 22, No 2, Jun 2023
- Vol 22, No 1, Mar 2023
- Vol 21, No 4, Dec 2022
- Vol 21, No 3, Sep 2022
- Vol 21, No 2, Jun 2022
- Vol 21, No 1, Mar 2022
- Vol 20, No 4, Dec 2021
- Vol 20, No 3, Sep 2021
- Vol 20, No 2, Jun 2021
- Vol 20, No 1, Mar 2021
- Vol 19, No 4, Dec 2020
- Vol 19, No 3, Sep 2020
- Vol 19, No 2, Jun 2020
- Vol 19, No 1, Mar 2020
- Vol 18, No 4, Dec 2019
- Vol 18, No 3, Sep 2019
- Vol 18, No 2, Jun 2019
- Vol 18, No 1, Mar 2019
- Vol 17, No 4, Dec 2018
- Vol 17, No 3, Sep 2018
- Vol 17, No 2, Jun 2018
- Vol 17, No 1, Mar 2018
- Vol 16, No 4, Dec 2017
- Vol 16, No 3, Sep 2017
- Vol 16, No 2, Jun 2017
- Vol 16, No 1, Mar 2017
- Vol 15, No 4, Dec 2016
- Vol 15, No 3, Sep 2016
- Vol 15, No 2, Jun 2016
- Vol 15, No 1, Mar 2016
- Vol 14, No 4, Dec 2015
- Vol 14, No 3, Sep 2015
- Vol 14, No 2, Jun 2015
- Vol 14, No 1, Mar 2015
- Vol 13, No 4, Dec 2014
- Vol 13, No 3, Sep 2014
- Vol 13, No 2, Jun 2014
- Vol 13, No 1, Mar 2014
- Vol 12, No 4, Dec 2013
- Vol 12, No 3, Sep 2013
- Vol 12, No 2, Jun 2013
- Vol 12, No 1, Mar 2013
- Vol 11, No 4, Dec 2012
- Vol 11, No 3, Sep 2012
- Vol 11, No 2, Jun 2012
- Vol 11, No 1, Mar 2012
- Vol 10, No 4, Dec 2011
- Vol 10, No 3, Sep 2011
- Vol 10, No 2, Jun 2011
- Vol 10, No 1, Mar 2011
- Vol 9, No 4, Dec 2010
- Vol 9, No 3, Sep 2010
- Vol 9, No 2, Jun 2010
- Vol 9, No 1, Mar 2010
- Vol 8, No 4, Dec 2009
- Vol 8, No 3, Sep 2009
- Vol 8, No 2, Jun 2009
- Vol 8, No 1, Mar 2009
- Vol 7, No 4, Dec 2008
- Vol 7, No 3, Sep 2008
- Vol 7, No 2, Jun 2008
- Vol 7, No 1, Mar 2008
- Vol 6, No 4, Dec 2007
- Vol 6, No 3, Sep 2007
- Vol 6, No 2, Jun 2007
- Vol 6, No 1, Mar 2007
- Vol 1, No 1, Mar 2002