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61.
Assessment of the performance of different compost models to manage urban household organic solid wastes 总被引:2,自引:1,他引:1
P. Ravi Kumar Ambika Jayaram R. K. Somashekar 《Clean Technologies and Environmental Policy》2009,11(4):473-484
The environmental, cultural, socio-economic and political conditions of each community greatly affect the municipality’s effort
and decision-making in managing household wastes. Composting at home can be used as a sound method of SWM, can manage the
waste at source itself thereby can increase their recycling. And vermicomposting is a viable and completely feasible option
at household level, provided it is acceptable to family members to handle the worms and to remove worm-casts subsequently.
In this regard, the present paper gives a methodological framework for assessing the management of urban household organic
wastes using different compost models to influence the actual efficiency and effectiveness of a municipality’s collection
and management services. The current study also deals with the challenges of solid waste management with a focus on the segregation
of compostable wastes from the non-compostable ones and their composting, recycling or disposal. The non-compostable wastes
can be left for recycling and re-use by the concerned authorities. The composting behavior and the efficiency of different
compost models have been dealt with, and it is concluded that vermicomposting model is the best option. Urban residents can
be educated to vermicompost not only their entire kitchen wastes but also garden wastes to reduce the burden on the municipal
councils. 相似文献
62.
63.
Subramanian Ramalingam Corinne E. Packard Ivar E. Reimanis 《Journal of the American Ceramic Society》2013,96(6):1909-1915
β‐eucryptite (LiAlSiO4), a member of the family of lithium aluminum silicates, is known to undergo a reversible pressure‐induced phase transformation at ~0.8 GPa to ε‐eucryptite. This study correlates the results between two techniques, in situ diamond anvil cell–Raman spectroscopy and nanoindentation experiments, to explore how doping (substituting Zn for Li) influences this pressure‐induced phase transformation. Diamond anvil cell tests carried up to 3 GPa hydrostatic stress under Raman spectroscopy were compared with nanoindentation results, which provide a more localized, multiaxial stress state. The results indicate that the magnitude of hysteresis observed (difference between the pressures required for the forward and reverse transformation) is lower for Zn‐doped β‐eucryptite; however, the onset of the phase transformation is unchanged by doping with Zn. Furthermore, calculations of activation volume from nanoindentation experiments yield similar values (~0.1 nm3) for pure and Zn‐doped β‐eucryptite, suggesting that the nucleation event that establishes the onset of the phase transformation is the same for both materials. 相似文献
64.
C.R. Subramanian 《Information Processing Letters》2006,99(6):227-229
An acyclic edge colouring of a graph is a proper edge colouring in which the union of any two colour classes does not contain a cycle, that is, forms a forest. It is known that there exists such a colouring using at most 16Δ(G) colours where Δ(G) denotes the maximum degree of a graph G. However, no non-trivial constructive bound (which works for all graphs) is known except for the straightforward distance 2 colouring which requires Δ2 colours. We analyse a simple O(mnΔ22(logΔ)) time greedy heuristic and show that it uses at most 5Δ(logΔ+2) colours on any graph. 相似文献
65.
Mechanical shaping of an aluminium alloy reinforced with Al2O3 particulates, (Al2O3)p-Al, was carried out by a cold rolling operation. Rolling was performed unidirectionally in a direction perpendicular to the extrusion direction of the composite, until edge cracks formed. Cold rolling was found to cause particulate cracking and interfacial debonding, as wellas the redistribution of (Al2O3)p. These parameters have significant roles in determining the elastic properties of the resultant composite. 相似文献
66.
M. Prikryl A. Kroupa G. C. Weatherly S. V. Subramanian 《Metallurgical and Materials Transactions A》1996,27(5):1149-1165
The precipitation behavior of a medium carbon steel microalloyed with Ti, V, and N has been studied by analytical transmission
electron microscopy in the as-cast and isothermally heat-treated states, as well as at different stages in the thermomechanical
processing of the steel. Mixed (Ti,V) nitrides were found in all the structures, but there was no evidence for mixed carbonitride
formation. The Hillert-Staffansson model was used to predict the composition of the nitrides as a function of tem-perature.
Upon prolonged aging many of the precipitates became “fragmented” and were no longer single crystals. At the same time, the
volume fraction of precipitates dropped, while their average Ti content increased. Possible explanations for this unexpected
behavior are discussed in this article. 相似文献
67.
Cubic oxide pyrochlores, Ln2Mo2O7, Ln=SmYb,Y, (Nd1?xAx), A=Er and Yb; 0 < x < 1.0, have been synthesized and electrical properties were examined in the range 77-600K. Semiconductor behavior is observed for Ln=EuYb, Y but the resistivity and Ea are low. Sm2Mo2O7 and Nd1?xYbxMo2O7 (0.05 ≤ x ≤ 0.1) exhibit semimetallic or metallic behavior. The mechanism of conduction in these compounds is explained on the basis of band model proposed by Sleight et al. 相似文献
68.
[3-14C] Eicosatrienoic acid (Δ11,14,17) chemically synthesized from [1-14C] linolenic acid was injected intracranially into 14-day old rats and sacrificed 8 hr later. The analysis of brain fatty
acids by radio-gas liquid chromatography before and after ozonolysis showed that the tetraene fraction consisted of a desaturated
product, Δ5,11,17–20∶4, and its elongated product, Δ7,13,16,19–22∶4. Both of these products, with a combined total of 61%
of the total radioactivity recovered in the tetraene fraction, contain a nonmethylene interrupted double bond system and,
therefore, are unsuitable for further desaturation. The other two components, Δ6,9,12,15–18∶4 and Δ8,11,14,17–20∶4, must have
been formed from Δ9,12,15–18∶3, formed by retroconversion of the starting material 20∶3, followed by desaturation and elongation.
These results suggest a lack of Δ8 desaturase in the developing brain, leading to formation of Δ5,11,14,17–20∶4 rather than Δ8,11,14,17–20∶4. Howeve, the nonmethylene
interrupted double bond isomer does not restrict chain elongation. 相似文献
69.
Some age replacement policies are investigated and conditions for the unique existence of an optimum policy are derived. The optimum policy is the one which minimizes the expected cost per unit time over an infinite time span or maximizes the proportion of time during which the system is in operation. Losses have been expressed through increasing operating cost, if the objective is to minimize the expected total cost per unit time and through increasing renewal times if the objective is to maximize the availability of the system. 相似文献
70.
A two-unit warm standby redundant system with repair and preventive maintenance is considered. The pdf of the life time of a unit while in standby is assumed to be Erlangian. The pdfs of all the other random variables are arbitrary. Identifying suitable regeneration points, expressions for the Laplace transforms of the availability and reliability of the system are derived. 相似文献