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161.
Doug M. Boyer Guntupalli V. R. Prasad David W. Krause Marc Godinot Anjali Goswami Omkar Verma John J. Flynn 《Die Naturwissenschaften》2010,97(4):365-377
Extant species of the supraordinal mammal clade Euarchonta belong to the orders Primates, Scandentia, or Dermoptera. The fossil
record of euarchontans suggests that they underwent their initial radiation during the Paleocene (65–55 million years ago)
in North America, Eurasia, and Africa. The time and place of origin is poorly resolved due to lack of definitive fossils of
euarchontan stem taxa. We describe a fragmentary humerus and two fragmentary ulnae from the latest Cretaceous of India that
bear significantly on this issue. The fossils are tentatively referred to Deccanolestes cf. hislopi due to their small size and the fact that Deccanolestes is the only eutherian dental taxon to have been recovered from the same locality. The new fossils are used to evaluate the
existing behavioral hypothesis that Deccanolestes was arboreal, and the competing phylogenetic hypotheses that Deccanolestes is a stem eutherian versus a stem euarchontan. The humerus resembles those of euarchontans in possessing a laterally keeled
ulnar trochlea, a distinct zona conoidea, and a spherical capitulum. These features also suggest an arboreal lifestyle. The
ulnar morphology is consistent with that of the humerus in reflecting an arboreal/scansorial animal. Detailed quantitative
comparisons indicate that, despite morphological correlates to euarchontan-like arboreality, the humerus of Deccanolestes is morphologically intermediate between those of Cretaceous “condylarthran” mammals and definitive Cenozoic euarchontans.
Additionally, humeri attributed to adapisoriculids are morphologically intermediate between those of Deccanolestes and definitive euarchontans. If adapisoriculids are euarchontans, as recently proposed, our results suggest that Deccanolestes is more basal. The tentative identification of Deccanolestes as a basal stem euarchontan suggests that (1) Placentalia began to diversify and Euarchonta originated before the Cretaceous–Tertiary
boundary and (2) the Indian subcontinent, Eurasia, and Africa are more likely places of origin for Euarchonta than is North
America. 相似文献
162.
Devi Prasad Mishra Patitapaban Sahu Durga Charan Panigrahi Vivekanand Jha R. Lokeswara Patnaik 《Environmental science and pollution research international》2014,21(3):2305-2312
This paper presents a comparative study of 222Rn emanation from the ore and backfill tailings in an underground uranium mine located at Jaduguda, India. The effects of surface area, porosity, 226Ra and moisture contents on 222Rn emanation rate were examined. The study revealed that the bulk porosity of backfill tailings is more than two orders of magnitude than that of the ore. The geometric mean radon emanation rates from the ore body and backfill tailings were found to be 10.01?×?10?3 and 1.03 Bq m?2 s?1, respectively. Significant positive linear correlations between 222Rn emanation rate and the 226Ra content of ore and tailings were observed. For normalised 226Ra content, the 222Rn emanation rate from tailings was found to be 283 times higher than the ore due to higher bulk porosity and surface area. The relative radon emanation from the tailings with moisture fraction of 0.14 was found to be 2.4 times higher than the oven-dried tailings. The study suggested that the mill tailings used as a backfill material significantly contributes to radon emanation as compared to the ore body itself and the 226Ra content and bulk porosity are the dominant factors for radon emanation into the mine atmosphere. 相似文献
163.
A series of oxime esters was synthesized by esterification of 3-ethoxy-4-benzaldehyde oxime with acid chlorides in the presence of triethylamine. They were evaluated for their in vitro antifungal activity against three pathogenic fungi, namely Rhizoctonia bataticola, Fusarium udum, and Alternaria porii, and their antibacterial activity against the three bacterial strains Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoneae. The compounds bearing medium-length alkyl chains showed greater activity than those with long alkyl chains. An electron-donating group in para position of the aryl ring confers highest activity. 相似文献
164.
Challenges of soil mixing using catalyzed hydrogen peroxide with rotating dual axis blending technology
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Prasad Kakarla Frederick Symmes Michael Temple Vincent Dello Russo Erik Hall William Caldicott Andrew Hoffman 《补救:环境净化治理成本、技术与工艺杂志》2017,27(3):45-54
Although known to be one of the most effective oxidants for treatment of organic contaminants, catalyzed hydrogen peroxide (CHP) is typically not used for soil mixing applications because of health and safety concerns related to vapor generation and very rapid rates of reaction in open excavations. In likely the first large‐scale in situ CHP soil mixing application, an enhanced CHP, modified Fenton's reagent (MFR), was applied during soil mixing at the Kearsarge Metallurgical Superfund Site in New Hampshire. An innovative rotating dual‐axis blender (DAB) technology was used to safely mix the MFR into low‐plasticity silt and clay soils to remediate residual 1,1,1‐trichloroethane (111TCA); 1,1‐dichloroethene (11DCE); and 1,4‐dioxane (14D). It was expected that the aggressive treatment approach using relatively “greener” hydrogen peroxide (HP) chemistry would effectively treat Site contaminants without significant byproduct impacts to groundwater or the adjacent pond. The remediation program was designed to treat approximately 3,000 cubic yards of residual source area soil in situ by aggressively mixing MFR into the soils. The subsurface interval treated was from 7 to 15 feet below ground surface. To accurately track the soil mixing process and MFR addition, the Site was divided into 109 10‐foot square treatment cells that were precisely located, dosed, and mixed using the DAB equipped with an on‐board GPS system. The use of stabilizing agents along with careful calculation of the peroxide dose helped to ensure vapor‐free conditions in the vicinity of the soil mixing operation. Real‐time sampling and monitoring were critical in identifying any posttreatment exceedences of the cleanup goals. This allowed retreatment and supplemental testing to occur without impacting the soil mixing/in situ chemical oxidation (ISCO) schedule. Posttreatment 24‐hr soil samples were collected from 56 random locations after ensuring that the HP had been completely consumed. The posttreatment test results showed that 111TCA and 11DCE concentrations were reduced to nondetect (ND) or below the cleanup goals of 150 μg/kg for 111TCA and 60 μg/kg for 11DCE. Supplemental posttreatment soil samples, collected six months after treatment, showed 100 percent compliance with the soil treatment goals. Groundwater samples collected one year after the MFR soil mixing treatment program showed either ND or low concentrations for 111TCA, 11DCE, and 14D. Successful stabilization and site restoration was performed after overcoming considerable challenges associated with loss of soil structure, high liquid content, and reduced bearing capacity of the blended soils. 相似文献
165.
Suvangshu Dutta Niranjan Karak Jyoti Prasad Saikia Bolin Kumar Konwar 《Journal of Polymers and the Environment》2010,18(3):167-176
Mesua ferrea L. seed oil (MFLSO) modified polyurethanes blends with epoxy and melamine formaldehyde (MF) resins have been studied for
biodegradation with two techniques, namely microbial degradation (broth culture technique) and natural soil burial degradation.
In the former technique, rate of increase in bacterial growth in polymer matrix was monitored for 12 days via a visible spectrophotometer
at the wavelength of 600 nm using McFarland turbidity as the standard. The soil burial method was performed using three different
soils under ambient conditions over a period of 6 months to correlate with natural degradation. Microorganism attack after
the soil burial biodegradation of 180 days was realized by the measurement of loss of weight and mechanical properties. Biodegradation
of the films was also evidenced by SEM, TGA and FTIR spectroscopic studies. The loss in intensity of the bands at ca. 1735 cm−1 and ca. 1050 cm−1 for ester linkages indicates biodegradation of the blends through degradation of ester group. Both microbial and soil burial
studies showed polyurethane/epoxy blends to be more biodegradable than polyurethane/MF blends. Further almost one step degradation
in TG analysis suggests degradation for both the blends to occur by breakage of ester links. The biodegradation of the blends
were further confirmed by SEM analyses. The study reveals that the modified MFLSO based polyurethane blends deserve the potential
to be applicable as “green binders” for polymer composite and surface coating applications. 相似文献
166.
Christian Seigneur Prasad Pai Ivar Tombach Charles McDade Pradeep Saxena Peter Mueller 《Journal of the Air & Waste Management Association (1995)》2013,63(5):835-848
ABSTRACT During wintertime, haze episodes occur in the Dallas-Ft. Worth (DFW) urban area. Such episodes are characterized by substantial light scattering by particles and relatively low absorption, leading to so-called “white haze.” The objective of this work was to assess whether reductions in the emissions of SO2 from specific coal-fired power plants located over 100 km from DFW could lead to a discernible change in the DFW white haze. To that end, the transport, dispersion, deposition, and chemistry of the plume of a major power plant were simulated using a reactive plume model (ROME). The realism of the plume model simulations was tested by comparing model calculations of plume concentrations with aircraft data of SF6 tracer concentrations and ozone concentrations. A second-order closure dispersion algorithm was shown to perform better than a first-order closure algorithm and the empirical Pasquill-Gifford-Turner algorithm. For plume impact assessment, three actual scenarios were simulated, two with clear-sky conditions and one with the presence of fog prior to the haze. The largest amount of sulfate formation was obtained for the fog episode. Therefore, a hypothetical scenario was constructed using the meteorological conditions of the fog episode with input data values adjusted to be more conducive to sulfate formation. The results of the simulations suggest that reductions in the power plant emissions lead to less than proportional reductions in sulfate concentrations in DFW for the fog scenario. Calculations of the associated effects on light scattering using Mie theory suggest that reduction in total (plume + ambient) light extinction of less than 13% would be obtained with a 44% reduction in emissions of SO2 from the modeled power plant. 相似文献
167.
Christian Seigneur Betty Pun Prasad Pai Jean-François Louis Paul Solomon Chris Emery 《Journal of the Air & Waste Management Association (1995)》2013,63(4):588-599
ABSTRACT Guidance for the performance evaluation of three-dimensional air quality modeling systems for particulate matter and visibility is presented. Four levels are considered: operational, diagnostic, mechanistic, and probabilistic evaluations. First, a comprehensive model evaluation should be conducted in at least two distinct geographical locations and for several meteorological episodes. Next, streamlined evaluations can be conducted for other similar applications if the comprehensive evaluation is deemed satisfactory. In all cases, the operational evaluation alone is insufficient, and some diagnostic evaluation must always be carried out. Recommendations are provided for designing field measurement programs that can provide the data needed for such model performance evaluations. 相似文献
168.
Lakshmi Raghu Nagendra Prasad Rentachintala Muni Reddy Mutukuru Gangireddy Pranab Kumar Mohapatra 《环境质量管理》2023,32(3):111-121
In the present study, Amaravati, the proposed city of India is considered to assess the impacts of urbanization on water quality of the Krishna River in the vicinity. Long-term surface water quality data of various parameters of Krishna River are obtained from Central Water Commission (CWC). Trends of various parameters are analyzed using a modified version of Mann-Kendall (M-K) test; bootstrapped M-K trend test with optional bias corrected pre-whitening and R programming are used affecting water quality prior to and at the commencement of urbanization. During the onset of urbanization, minimum BOD is decreased from 0.49 to 0.2 mg/L, while the maximum BOD is increased by 67.7%. Dissolved oxygen's (DO) minimum value is decreased by 29.33% while maximum DO value is decreased by 4.47% at the beginning of urbanization. During the process of urbanization, total coliform's minimum count is increased to 330 from 2 MPN/100 ml while the maximum count of total coliforms is increased to 16,000 from 2400 MPN/100 ml. Faecal coilform's minimum count is increased from 2 to 80 MPN/100 ml while maximum count is increased to 16,000 from 800 MPN/100 ml during urbanization. It is found that due to urbanization, pH, DO values exceed the allowable limit. 相似文献
169.
Kumbhar Sudhir Hankare Prakash Sabale Sandip Kumbhar Rajendra 《Environmental Chemistry Letters》2019,17(2):1161-1166
Environmental Chemistry Letters - We have extracted a new brown-coloured natural dye from the leaves of Ficus amplissima Smith using Soxhlet extraction. The dye was assessed for... 相似文献
170.
We present soil surface nitrogen (N) budgets for the agricultural sector of India, calculated as inputs minus outputs over 21 agroecological zones (AEZ), for 2000–2001. Nearly 35.4 Tg N was input from different sources, with output from harvested crops of about 21.2 Tg N. Soil surface N balance for agricultural lands showed a surplus of about 14.4 Tg. Livestock manure constituted 44% of total inputs, followed by 32.5% from inorganic fertilizer, 11.9% from atmospheric deposition and 11.6% from N fixation. Though the N balance was negative in some states, due to aggregation of states in agroecological regions, all regions showed surplus N loads, with a range of about 19–110 kg/ha. The lowest loads were found for AEZ 17 in the Eastern Himalaya, with 19 kg/ha surplus, and the highest surplus N load in AEZ 7 with 111 kg/ha in Deccan plateau and the Eastern Ghats. Temporal trends in fertilizer consumption from 1950–2000 for India suggested a massive increase of ~47-fold, whereas production of major crops, rice, wheat and maize, increased nearly ~4.0-, 10- and 6-fold, respectively. Fertilizer consumption patterns were highly concentrated in Tamilnadu (204.6 kg/ha), Haryana (132.0 kg/ha) and Punjab (148.6 kg/ha). The paper addresses the role of agricultural intensification and its implications for water quality in agroecological regions of India. 相似文献