排序方式: 共有45条查询结果,搜索用时 31 毫秒
21.
G.L. Sivakumar Babu Sandeep Kumar Chouksey Krishna R. Reddy 《Waste management (New York, N.Y.)》2013,33(10):2029-2034
In the analysis and design of municipal solid waste (MSW) landfills, there are many uncertainties associated with the properties of MSW during and after MSW placement. Several studies are performed involving different laboratory and field tests to understand the complex behavior and properties of MSW, and based on these studies, different models are proposed for the analysis of time dependent settlement response of MSW. For the analysis of MSW settlement, it is very important to account for the variability of model parameters that reflect different processes such as primary compression under loading, mechanical creep and biodegradation. In this paper, regression equations based on response surface method (RSM) are used to represent the complex behavior of MSW using a newly developed constitutive model. An approach to assess landfill capacities and develop landfill closure plans based on prediction of landfill settlements is proposed. The variability associated with model parameters relating to primary compression, mechanical creep and biodegradation are used to examine their influence on MSW settlement using reliability analysis framework and influence of various parameters on the settlement of MSW are estimated through sensitivity analysis. 相似文献
22.
Akash Sivakumar Sivaprakash Baskaran Rajamohan Natarajan Vo Dai-Viet N. 《Environmental Chemistry Letters》2023,21(3):1477-1497
Environmental Chemistry Letters - Global warming is partly due to excessive carbon dioxide emissions, calling for methods to capture carbon dioxide for conversion into value-added... 相似文献
23.
Economic costs imposed by climatic extremes have been increasing over the years and are expected to follow a similar trend in the coming years as well. Such costs are incurred due to two factors: (1) natural climate variability and anthropogenic climate change and (2) exposure and vulnerability of socio-economic factors. The impact of these factors as identified separately through a ‘normalisation technique’ is analysed in the existing normalisation studies conducted mostly in developed country contexts; these have produced mixed results. However, one needs to enquire about the influence of the above two factors in a developing country context where the anticipated impacts of climate extremes are significant. This study, therefore, makes an attempt to adjust impact data, in terms of the reported population affected and economic damages of three extreme events, namely cyclones, floods and droughts, together for societal changes between 1972 and 2009 in Odisha in eastern India. Further, the second component is analysed in two ways: (1) assuming that exposed socio-economic factors are equally vulnerable similar to the other normalisation studies, i.e. no adaptation and (2) incorporating adaptation in the existing normalisation methods—which has attracted less attention so far in the literature. The results suggest that: (a) both the natural climate variability and the socio-economic factors influence the increasing damages in the recent decades, and (b) when adaptation is introduced in the normalisation model, economic losses have reduced significantly compared to the estimates using the existing normalisation models. 相似文献
24.
Jayganesh Duraipandian Tamilarasan Rengasamy Sivakumar Vadivelu 《Journal of Polymers and the Environment》2017,25(4):1062-1071
This research article describes, an eco-friendly activated carbon prepared from the Gracilaria corticata seaweeds which was employed for the preparation of biodegradable polymeric beads for the efficient removal of crystal violet dye in an aqueous solution. The presence of chemical functional groups in the adsorbent material was detected using FTIR spectroscopy. The morphology and physical phases of the adsorbent materials were analyzed using SEM and XRD studies respectively. Batch mode dye adsorption behavior of the activated carbon/Zn/alginate polymeric beads was investigated as a function of dosage, solution pH, contact time, initial dye concentration and temperature. Maximum dye removal was observed at a pH of 5.0, 1 g of adsorbent dosage with 60 mg/L dye concentration, 50 min of contact time and at 30 °C. The equilibrium modeling studies were analyzed with Freundlich and Langmuir adsorption isotherms and the adsorption dynamics was predicted with Lagergren’s pseudo-first order, pseudo-second order equations and intra particle diffusion models. The process of dye removal followed a pseudo second-order kinetics rather than pseudo first order. The thermodynamic parameters like standard Gibbs free energy change (ΔG°), enthalpy change (ΔH°) and entropy change (ΔS°) were determined and the results imply that the adsorption process was spontaneous, endothermic and increases the randomness between the adsorbent and adsorbate. The results from the experimental and correlation data reveal that the Gracilaria corticata activated carbon/Zn/alginate polymeric beads have proved to be an excellent adsorbent material for the removal of CV dye. 相似文献
25.
Deepa R Senthilkumar P Sivakumar S Duraisamy P Subbhuraam CV 《Environmental monitoring and assessment》2006,116(1-3):185-195
The Cu accumulation capacity of stem cuttings of Portulaca oleracea was assessed in two different soils, alfisol and vertisol, which differ from each other mainly due to their clay content~—
several fold lower in the former than in the latter. The DTPA extractable concentration of Cu in soil and the level of its
accumulation in stem cuttings were, therefore, greater in alfisol than in vertisol. In the mixed soils, the DTPA extractable
as well as plant accumulated levels of Cu decreased with an increase in the proportion of vertisol. With an increase in the
soil available and plant accumulated Cu, a decrease has been observed in the ability of stem cuttings to regenerate leaves
and roots. As a consequence biomass reduction has been observed with an increase in the concentration of Cu in the soil and
plant body. In view of comparatively low availability of Cu in vertisol, regeneration of stem cuttings occurred up to a concentration
of 1600 $μ gofCu/gofsoil, whereasinalfisolitoccurredonlyupto200μ g of Cu/g of soil. The results of the present study showed that P. oleracea stem cutting is an accumulator of Cu and the availability of Cu in soils could be manipulated through addition of clay since
the plant available concentration of Cu is less in the soil (vertisol) with high clay content. 相似文献
26.
Tomohiko Isobe Shohei P. Ogawa Rina Sugimoto Karri Ramu Agus Sudaryanto Govindan Malarvannan Gnanasekaran Devanathan Babu Rajendran Ramaswamy Natesan Munuswamy Deavaraj Sankar Ganesh Jeyaraj Sivakumar A. Sethuraman V. Parthasarathy Annamalai Subramanian Jennifer Field Shinsuke Tanabe 《Environmental monitoring and assessment》2013,185(7):5627-5637
Perchlorate contamination was investigated in groundwater and surface water from Sivakasi and Madurai in the Tamil Nadu State of South India. Sensitive determination of perchlorate (LOQ?=?0.005 μg/L) was achieved by large-volume (500 μL) injection ion chromatography coupled with tandem mass spectrometry. Concentrations of perchlorate were <0.005–7,690 μg/L in groundwater (n?=?60), <0.005–30.2 μg/L in surface water (n?=?11), and 0.063–0.393 μg/L in tap water (n?=?3). Levels in groundwater were significantly higher in the fireworks factory area than in the other locations, indicating that the fireworks and safety match industries are principal sources of perchlorate pollution. This is the first study that reports the contamination status of perchlorate in this area and reveals firework manufacture to be the pollution source. Since perchlorate levels in 17 out of 57 groundwater samples from Sivakasi, and none from Madurai, exceeded the drinking water guideline level proposed by USEPA (15 μg/L), further investigation on human health is warranted. 相似文献
27.
Wang Shuang Viswanathan Karthickeyan Esakkimuthu Sivakumar Azad Kalam 《Environmental science and pollution research international》2021,28(10):12026-12040
Environmental Science and Pollution Research - This study offered a comprehensive investigation on engine performance and emission characteristics of Kirloskar make tangentially vertical (TV1)... 相似文献
28.
Vigneshwaran Sivakumar Sirajudheen Palliyalil Sajna Valiya Peedikakkal Park Chang Min Meenakshi Sankaran 《Environmental science and pollution research international》2023,30(10):24876-24889
Environmental Science and Pollution Research - A hetero-structured metal organic framework of Cu-BTC and Fe2O3 nano-photocatalyst were tethered over chitosan using the hydrothermal method and... 相似文献
29.
Karthikeyan Sivakumar Arumugam Shanmugasundaram Muthumanickam Jayaprakash Kulandaisamy Prabakaran Subramanian Muthusamy Annadurai Ramachandran Senapathi Venkatramanan Sekar Selvam 《Environmental science and pollution research international》2021,28(15):18651-18666
Environmental Science and Pollution Research - Groundwater is the major freshwater resource in urban and rural areas of India that provides potable water. The quality evaluation of existing... 相似文献
30.
V. Sivakumar F. Chandrasekaran G. Swaminathan P.G. Rao 《Journal of Cleaner Production》2009,17(1):101-104
Studies on ultrasound-assisted processes are gaining importance due to its effectiveness and facilitating green method in processing. Degreasing of skin/hide prior to tanning process is an important unit operation. Presence of large amounts of natural fat at the interior of skin/hide matrix makes degreasing process a challenging one. Conventionally, organic solvent and/or detergent based degreasing process are employed leading to environmental problems. In the present paper, the use of power ultrasound in aqueous degreasing process has been studied and compared with different degreasing systems. Glutaraldehyde pre-tanning has also been employed for carrying out the degreasing process at ultrasonic bath temperature. The results indicate that there is a significant increase in the degreasing efficiency due to the application of ultrasound. About 2-fold increase in fat removal has been observed due to the use of ultrasound as compared to control under the given process conditions. Comparing the degreasing efficiencies of the solvent with aqueous based ultrasonic processes, about 80% of the solvent degreasing efficiency could be obtained for aqueous degreasing process. This novel ultrasonic process helps in making aqueous degreasing process a viable option, which is eco-friendly even dispensing with temperature control measures. 相似文献