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91.
The effect of intratracheally administered DDT (5 mg/100 g body weight) or endosulfan (1 mg/100 g body weight) for three consecutive days has been studied on lipid metabolism of rat lung subcellular fractions. Both the insecticides did not affect the lung weight and the protein contents of microsomes, lamellar bodies and surfactant but significantly increased the phospholipid contents of microsomal and surfactant system. Most of the neutral lipid components of lung subcellular fractions were also increased by DDT or endosulfan treatments, except that of surfactant triglycerides which were decreased by DDT treatment. DDT or endosulfan both increased the incorporation of radioactive [methyl-3H]choline into microsomal phosphatidylcholine (PC) and surfactant dipalmitoylphosphatidylcholine (DPPC) without affecting the incorporation of radioactive [methyl-14C]methionine, showing the increased synthesis of PC via CDPcholine pathway. The results presented in this communication showed that DDT and endosulfan, the two different chloroinsecticides have similar effects on microsomal lipid metabolism but produce different biochemical manifestations on the secretion of surfactant phospholipids.  相似文献   
92.
An assessment of human interference in Kedarnath Wildlife Sanctuary (KWLS) showed huge dependence of local communities on forest fringes. KWLS is under active consideration as a national park because of its unique flora and fauna. Studies have evidenced habitat destruction and successional changes in the area because of ongoing unsustainable harvesting and logging. The present study provides an integrated approach towards evaluating resource extraction and management of the sanctuary. The study was based on in-depth semi-structured interviews and group discussions with local inhabitants of six villages and with forest officials. In addition, regeneration patterns and vegetation analysis was conducted in three land tenurial systems: community forest (CF), reserve forest (RF) and protected forest (PF). Key issues identified were wildlife offences, encroachment, pressure from unsustainable harvesting of resources and lack of livelihood opportunities. Ecological studies showed continuous change in regeneration patterns in forest patches/stands. The local survey stressed managing sanctuary fringes considering the village economy, social issues and resource requirements, and enhancing on-farm resource production to reduce pressure on forests. Forest personnel demanded more training on encroachment and poaching, these being major threats to biodiversity and bio-resources. Supporting and providing better livelihood opportunities is a viable option for minimizing pressure and managing biodiversity of the area through active community participation. This study generated useful outcomes and strategies for advancing policies to reduce pressure and overcome management constraints in the sanctuary.  相似文献   
93.
94.
Granular activated carbon (GAC) loaded with trinitrotoluene (TNT) and nitrobenzene (NB) were subjected to different atmospheres, such as nitrogen, oxygen, air, steam and an air-steam mixture, at varying temperatures and for different time intervals for regeneration. The air-steam mixture proved to be the best regenerating media for the explosive-loaded GACs. The regeneration of the activated carbon was found to be above 85% for TNT and above 90% for NB loaded carbons.  相似文献   
95.
Biobased polyurethanes from soybean oil–derived polyols and polymeric diphenylmethane diisocyanate (pMDI) are prepared and their thermomechanical properties are studied and evaluated. The cross-linked biobased polyurethanes being prepared from soy phosphate ester polyols with hydroxyl contents ranging from 122 to 145 mg KOH/g and pMDI within 5 min of reaction time at 150°C in absence of any catalyst show cross-linking densities ranging from 1.8 × 103 to 3.0 × 103 M/m3, whereas glass transition temperatures vary from approximately 69 to 82°C. The loss factor (tan ) curves show single peaks for all these biobased polyurethanes, thus indicating a single-phase system. The storage moduli (G) at 30°C range from 4 × 108 to 1.3 × 109 Pa. Upon postcure at 150°C, the thermomechanical properties can be optimized. Cross-link densities are improved significantly for hydroxyl content of 139 and 145 mg KOH/g at curing time of 24 h. Similarly, glass transition temperature (Tg) and storage moduli around and after Tg are increased. Meanwhile, tan intensities decrease as result of restricted chain mobility. Longer exposure time (24 h) induces thermal degradation, as evidenced by thermogravimetric analysis (TGA). The dynamic mechanical (DMA) analysis shows that postcure at 100°C for times exceeding 24 h also leads to improved properties. However, cross-linking densities are lower compared to postcure carried out at 150°C.  相似文献   
96.
In an urban-transit bus,fueled by biodiesel in Toledo,Ohio,single inhalable particle samples in October 2008 were collected and detected by scanning electron microscopy and energy dispersive X-ray spectrometry(SEM/EDS).Particle size analysis found bimodal distribution at 0.2 and 0.5 μm.The particle morphology was characterized by 14 different shape clusters:square,pentagon,hexagon,heptagon,octagon,nonagon,decagon,agglomerate,sphere,triangle,oblong,strip,line or stick,and unknown,by quantitative order.The square particles were common in the samples.Round and triangle particles are more,and pentagon,hexagon,heptagon,octagon,nonagon,decagon,strip,line or sticks are less.Agglomerate particles were found in abundance.The surface of most particles was coarse with a fractal edge that can provide a suitable chemical reaction bed in the polluted atmospheric environment.The three sorts of surface patterns of squares were smooth,semi-smooth,and coarse.The three sorts of square surface patterns represented the morphological characteristics of single inhalable particles in the air inside the bus in Toledo.The size and shape distribution results were compared to those obtained for a bus using ultra low sulfur diesel.  相似文献   
97.
High bat (Chiroptera) diversity in the Early Eocene of India   总被引:1,自引:0,他引:1  
The geographic origin of bats is still unknown, and fossils of earliest bats are rare and poorly diversified, with, maybe, the exception of Europe. The earliest bats are recorded from the Early Eocene of North America, Europe, North Africa and Australia where they seem to appear suddenly and simultaneously. Until now, the oldest record in Asia was from the Middle Eocene. In this paper, we report the discovery of the oldest bat fauna of Asia dating from the Early Eocene of the Cambay Formation at Vastan Lignite Mine in Western India. The fossil taxa are described on the basis of well-preserved fragments of dentaries and lower teeth. The fauna is highly diversified and is represented by seven species belonging to seven genera and at least four families. Two genera and five species are new. Three species exhibit very primitive dental characters, whereas four others indicate more advanced states. Unexpectedly, this fauna presents strong affinities with the European faunas from the French Paris Basin and the German Messel locality. This could result from the limited fossil record of bats in Asia, but could also suggest new palaeobiogeographic scenarios involving the relative position of India during the Early Eocene.  相似文献   
98.
The river Paz is a transboundary river that flows through Guatemala and El Salvador. Its frequent floods endanger the lives and livelihoods of downstream communities. Attempts have previously been made to develop flood management programmes for this watershed. However, these approaches were generally made by high-level governmental institutions with few if any contributions from floodplain communities and other stakeholders. Recognising that public consultation is a key aspect in flood management programmes, we intend in this work to extract different stakeholders' views regarding current and future flooding and flood management programmes in the Paz River basin. This is achieved using Future Scenarios Workshops with a projected time horizon of 30 years. The exercise was expected to identify consensual short- and medium–long-term flood management strategies for the Paz River basin that draws on input from inhabitants of flood-prone areas and other stakeholders.  相似文献   
99.
100.
Environmental Chemistry Letters - Modern biomass and organic waste are becoming major, carbon-neutral sources of fine chemicals, biomolecules and fuels to replace fossil fuel products. As a...  相似文献   
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