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21.
This laboratory study examined the combined effects of male and female behaviors on the outcome of mating encounters in Octopus bimaculoides. We found that male–male competition for mating opportunities depends on female maturity; the presence of immature females elicited significantly higher levels of aggression between competing males. We conclude that males are able to assess the reproductive status of females. The study also found that immature and mature females resisted male mating attempts to a similar extent but that males that showed more aggression toward male competitors were able to spend more time in contact with females. We suggest that the lack of prominent visual displays in these mating trials indicates the importance of chemical cues in Octopus mating systems, as has been demonstrated for other cephalopods. This study contributes to the growing research on cephalopod mating systems and in particular shows that Octopus mating dynamics may be more behaviorally complex than initially assumed.  相似文献   
22.
In the present study, influence of talc on thermal, mechanical and rheological behavior of PLA is investigated and the structure?Cproperty correlation for the PLA/talc composites is established. Poly(lactic acid)/talc composites are prepared by melt mixing of PLA with talc in twin screw extruder followed by blown film processing. Various characterizations techniques are used to evaluate thermal, morphological, mechanical and rheological behavior of PLA/talc composites and its blown film. DSC analysis showed that degree of crystallinity of PLA/talc composites was higher than that of neat PLA because of nucleating ability of talc. Spherulite morphology of PLA/talc composites showed that talc has increased nucleation density of spherulite having smaller radius than that of neat PLA. Talc is effective in enhancing tensile modulus and storage modulus of PLA due to reinforcing ability of talc particles.  相似文献   
23.
The plastic components from waste mobile phones were sorted and characterized using visual, spectroscopic and thermal methods. The sustainable strength of the recovered plastics was investigated by comparing their mechanical and thermal properties with commercially used reference materials. The results revealed that the recovered polymers have significant potential to be reused. However, some properties, such as impact strength and tensile modulus, are significantly low compared to virgin materials and need further improvement. The samples were also tested for brominated flame retardants (BFRs) using gas chromatography–mass spectrometry technique, and the results indicated the absence of BFR in recovered plastics; hence, these can be processed without any risk of BFR toxicity.  相似文献   
24.
The current policy of many state governments in India to supply cheap and subsidized power to farmers for irrigation pumping is being increasingly questioned by many environmentalists and agriculturalists. States where power tariffs for irrigation are subsidized and cheap have seen a fall in their groundwater tables which could threaten the long-term sustainability of irrigated agriculture in these areas. This paper presents the results of a survey, undertaken to understand the effect of energy pricing on groundwater tables. The paper argues that current energy pricing policies are at cross purposes to groundwater conservation. Equity effects of energy pricing for irrigation pumping is also discussed .  相似文献   
25.
Arachis hypogaea hulls, an agricultural waste, were used to prepare activated carbon by chemical activation with zinc chloride under four different activation atmospheres. The most important parameter in chemical activation was found to be the chemical ratio (activating agent/precursor). Carbonization temperature and time are the other two important variables, which had significant effect on the pore structure of carbon. The maximum Brunquer-Emmett-Teller (BET) surface area and micropore volume of the activated carbon was found to be 418 m2/g and 0.28 cm3/g, respectively. The activated carbon developed shows substantial capability to adsorb phenol from aqueous solutions. The kinetic data were fitted to the models of intraparticle diffusion, pseudo-second-order, and Lagergren, and followed more closely the pseudo-second-order chemisorption model. The isotherm equilibrium data were well fitted by the Langmuir and Freundlich models. Solution pH has significant effect on adsorption and the maximum uptake of phenol was reported at pH 3.5.  相似文献   
26.
The paint industry in India is broadly classified into two categories: organized sector and unorganized sector. Multinational and big Indian companies form the organized sector, whereas the small- and medium-scale industries which produce paints for the local market form the unorganized sector. The present study was undertaken to determine the level of lead in decorative paints in India. A total of 148 paint samples sourced from four organized sector companies and six unorganized sector companies were analyzed for the total lead content. Results of this study reveal that 39 % of the total paints tested (n = 148) contain lead more than 300 ppm, the voluntary limit prescribed by Bureau of Indian Standards, BIS (IS 15489:2011), and 45 % of the tested paints contain lead more than 90 ppm, the US limit. Further analysis of the data indicates that only 5 % of the tested paints manufactured by organized sector companies contain lead more than 300 ppm (n = 91), whereas 93 % of the tested paints manufactured by unorganized sector companies contain lead more than 300 ppm (n = 57). Comparison with earlier reported data suggests that while organized sector companies are gradually abandoning the use of lead-based compounds in their paints, the unorganized sector companies are still adding lead-based compounds intentionally in their paints despite the potential health hazards associated with it. The maximum concentration of lead obtained was 80,350 ppm in one of the paints manufactured by an unorganized sector company. The presence of high concentration of lead in yellow and green color paints indicates that color can be a predictor of lead content in decorative paints.  相似文献   
27.
Seasonal observations on water-quality parameters and chlorophyll-a in the coastal waters off Kalpakkam, southeast coast of India, was carried out covering an area of about 30 km(2) to find out the variations in physicochemical properties during a monsoonal cycle of the year. Most of the parameters exhibited a significant spatial and seasonal variation. It revealed that the coastal water was significantly influenced by freshwater input from the nearby backwaters during North-east monsoon and post-monsoon periods. A marginal increase in pH from coast towards offshore was noticed during the observation. Relatively low salinity values were observed during pre and post monsoon when compared to summer. Bottom water was found to be highly turbid during summer and pre-monsoon conditions when compared to surface. This could be attributed to the strong northerly wind and northward current prior to the onset of southwest monsoon. N, P and Si based nutrients are relatively high in their concentration in the bottom water. Nitrate was significantly high during post-monsoon and contributed greatly towards total nitrogen as evident from the statistical correlation. Ammonia concentration was relatively high in the bottom samples during all the seasons except on a few occasions during post-monsoon. In general, phosphate and total phosphorous values remained low and particularly so in the surface water. Higher silicate concentration was observed in the bottom water, and there was a reducing trend towards offshore. High chlorophyll-a values were observed during summer and surface water was found to have higher pigment concentrations as compared to the bottom. Results show that phosphate acts as the limiting factor for phytoplankton production particularly during post-monsoon period whereas; none of the nutrients were found to be limiting the phytoplankton growth during other seasons.  相似文献   
28.
Eco-friendly completely biodegradable biocomposites have been fabricated using polylactic acid (PLA) and banana fiber (BF) employing melt blending technique followed by compression moulding. BF??s were surface treated by NaOH and various silanes viz. 3-aminopropyltriethoxysilane and bis-(3-triethoxy silyl propyl) tetrasulfane (Si69) to improve the compatibility of the fibers within the matrix polymer. Characterization studies have been suggested that a better fiber matrix interaction because of the newly added functionalities on the BF surface as a result of chemical treatments. In comparison with the untreated BF biocomposite, an increase of 136% in tensile strength and 57% in impact strength has been observed for Si69 treated BF biocomposite. DSC thermograms of surface treated BF biocomposites revealed an increase in glass transition and melting transition due to the more restricted macromolecular movement as a result of better matrix fiber interaction. The thermal stability in the biocomposites also increased in case of biocomposite made up of BF treated with Si69. Viscoelastic measurements using DMA confirmed an increase of storage modulus and low damping values for the same biocomposite. Biodegradation studies of the biocomposites have been investigated in Burkholderia cepacia medium through morphological and weight loss studies.  相似文献   
29.
The effect of calcium and magnesium either singly or in combination on accumulation of cadmium and copper in Labeo rohita (rohu) and Catla catla (catla) was investigated in this study under laboratory conditions. The investigation showed that copper accumulation in rohu exposed to 0.25 mg L?1 of copper for 14 days reduced from 31.0 ± 0.4 mg kg?1 at no calcium/magnesium treatment to 3.5 ± 0.2 and 2.2 ± 0.1 mg kg?1, respectively, at 75 mg L?1 calcium or magnesium treatment. The copper level in catla exposed to 0.20 mg L?1 of copper for 14 days reduced from 5.7 ± 0.1 mg kg?1 at no calcium/magnesium treatment to 3.4 ± 0.2 and 3.3 ± 0.1 mg kg?1, respectively, at 300 mg L?1 calcium or magnesium treatment. The cadmium accumulation in rohu exposed to 0.20 mg L?1 of cadmium for 14 days reduced from 1.7 ± 0.1 mg kg?1 at no magnesium treatment to 1.4 ± 0.1 mg kg?1 at 120 mg L?1 magnesium treatment. The cadmium accumulation in catla exposed to 0.20 mg L?1 of cadmium for 14 days reduced from 0.8 ± 0.2 mg kg?1 at no magnesium treatment to 0.6 ± 0.2 mg kg?1 at 80 mg L?1 magnesium treatment. Copper and cadmium treatments also reduced some essential microelements of rohu and catla. Both the fishes restored these elements at different levels of calcium and magnesium.  相似文献   
30.
Journal of Polymers and the Environment - The major roadblock for recycling of waste electrical and electronic equipments (WEEE) depends on the viability of sorting process, which is a complex...  相似文献   
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