Carbonaceous and inorganic species in PM<Subscript>10</Subscript> during wintertime over Giridih,Jharkhand (India)     

S. K. Sharma  T. K. Mandal  A. K. De  N. C. Deb  Srishti Jain  Mohit Saxena  S. Pal  A. K. Choudhuri  Saraswati 《Journal of Atmospheric Chemistry》2018,75(2):219-233

Ambient concentrations of organic carbon (OC), elemental carbon (EC) and water soluble inorganic ionic components (WSIC) of PM₁₀ were studied at Giridih, Jharkhand, a sub-urban site near the Indo Gangatic Plain (IGP) of India during two consecutive winter seasons (November 2011–February 2012 and November 2012–February 2013). The abundance of carbonaceous and water soluble inorganic species of PM₁₀ was recorded at the study site of Giridih. During winter 2011–12, the average concentrations of PM₁₀, OC, EC and WSIC were 180.2?±?46.4; 37.2?±?6.2; 15.2?±?5.4 and 18.0?±?5.1 μg m^?3, respectively. Similar concentrations of PM₁₀, OC, EC and WSIC were also recorded during winter 2012–13. In the present case, a positive linear trend is observed between OC and EC at sampling site of Giridih indicates the coal burning, as well as dispersed coal powder and vehicular emissions may be the source of carbonaceous aerosols. The principal components analysis (PCA) also identifies the contribution of coal burning? +?soil dust, vehicular emissions?+?biomass burning and seconday aerosol to PM₁₀ mass concentration at the study site. Backward trajectoy and potential source contributing function (PSCF) analysis indicated that the aerosols being transported to Giridih from upwind IGP (Punjab, Haryana, Uttar Pradesh and Bihar) and surrounding region.  相似文献   

High-pressure synthesis of mesoporous stishovite: potential applications in mineral physics     

Vincenzo Stagno  Manik Mandal  Kai Landskron  Yingwei Fei 《Physics and Chemistry of Minerals》2015,42(6):509-515

  相似文献   

Stable isotopic and geochemical data for inferring sources of recharge and groundwater flow on the volcanic island of Rishiri,Japan     

Ajit K. Mandal  Jing Zhang  Kazuyoshi Asai 《Applied Geochemistry》2011,26(9-10):1741-1751

An isotopic and chemical study was conducted on precipitation, spring water, streams, groundwater wells and submarine groundwater discharge (SGD) to constrain the recharge areas and flow paths of SGD. The isotopic values of precipitation were used to determine the local meteoric water lines (LMWLs) of Rishiri Island. The d-excess values of precipitation showed seasonal variation, with lows of 2.5‰ in the summer and highs of 24.2‰ in the winter. The d-excess values of spring water, streams, groundwater wells and SGD ranged from 12.5‰ to 23.0‰, indicating that the resulting waters were a mix of two seasons of precipitation. The isotopic composition of the groundwater wells sampled along the coast and SGD showed more negative values than that of the spring water sampled along the coast. This indicated that SGD recharged at high altitudes and flowed into the sea. The isotopic and chemical composition of SGD indicated unidirectional flow from land to sea.  相似文献   

Paleoenvironment of deposition of the Dupi Tila Formation,Lalmai Hills,Comilla, Bangladesh     

Mrinal Kanti Roy  Syed Samsuddin Ahmed  Tapas Kumar Bhattacharjee  Sultan Mahmud  Md. Moniruzzaman  Md. Masidul Haque  Sudip Saha  Md. Ismail Molla  Pulin Chandra Roy 《Journal of the Geological Society of India》2012,80(3):409-419

The Dupi Tila Formation is composed of yellow to light brown medium to very fine moderately hard to loose sandstone, siltstone, silty clay, mudstone and shale with some conglomerates with clasts of petrified wood. The lithofacies of matrix supported conglomerate, trough cross bedded conglomerate, massive sandstone, trough cross bedded sandstone, planar cross bedded sandstone, ripple cross laminated sandstone-siltstone, flaser laminated sandstone-shale, lenticular laminated sandstone-siltstone-shale, parallel laminated sandstone-siltstone, wavy laminated shale, parallel laminated blue shale, and mudstone are delineated within this formation. Based on the grain size, sedimentary structures, water depth and genesis of individual facies, facies are grouped into three types of facies associations like (i) coarse-grained conglomerate facies association in relation to tractive current deposits of alluvial fan set up at the base of litho-succession (FAC), (ii) medium to fine-grained sandstone-siltstone-mudstone facies association or facies association in relation to strong tide (FAT) characterizing the middle part of litho-succession, (iii) very fine-grained sandstone-siltstone-mudstone facies association in relation to less frequent weak tide or heterolithic facies association (FAHL) characterizing upper part of litho-succession and shallow marine facies association (FASM) composing the uppermost litho-succession. Presence of gluconite indicates that the depositional environment was shallow to deep marine. The dominant paleoflow direction during the deposition of Dupi Tila Formation was toward southeast to southwestern direction. The rivers were of braided type at the piedmont alluvial depositional set up at the lower part, which later changed to estuarine-tidal flat type environmental set up in the middle part to upper part and paleo-environment was shallow marine in the uppermost part.  相似文献   

Classification of cyclone hazard prone districts of India     

M. Mohapatra  G. S. Mandal  B. K. Bandyopadhyay  Ajit Tyagi  U. C. Mohanty 《Natural Hazards》2012,63(3):1601-1620

Hazards associated with tropical cyclones are long-duration rotatory high-velocity winds, very heavy rain and storm tide. India has a coastline of about 7,516?km of which 5,400?km is along the mainland. The entire coast is affected by cyclones with varying frequency and intensity. The India Meteorological Department (IMD) is the nodal government agency that provides weather services related to cyclones in India. However, IMD has not identified cyclone-prone districts following any specific definition though the districts for which cyclone warnings are issued have been identified. On the other hand, for the purpose of better cyclone disaster management in the country, it is necessary to define cyclone proneness and identify cyclone-prone coastal districts. It is also necessary to decide degree of hazard proneness of a district by considering cyclone parameters so that mitigation measures are prioritised. In this context, an attempt has been made to prepare a list of cyclone hazard prone districts by adopting hazard criteria. Out of 96 districts under consideration, 12, 45, 31 and 08 districts are in very high, high, moderate and low categories of proneness, respectively. In general, the coastal districts of West Bengal, Orissa, Andhra Pradesh and Tamil Nadu are more prone and are in the high to very high category. The cyclone hazard proneness factor is very high for the districts of Nellore, East Godawari, and Krishna in Andhra Pradesh; Yanam in Puducherry; Balasore, Bhadrak, Kendrapara and Jagatsinghpur in Orissa; and South and North 24 Parganas, Medinipur and Kolkata in West Bengal. The results give a realistic picture of degree of cyclone hazard proneness of districts, as they represent the frequency and intensity of land falling cyclones along with all other hazards like rainfall, wind and storm surge. The categorisation of districts with degree of proneness also tallies with observed pictures. Therefore, this classification of coastal districts based on hazard may be considered for all the required purposes including coastal zone management and planning. However, the vulnerability of the place has not been taken into consideration. Therefore, composite cyclone risk of a district, which is the product of hazard and vulnerability, needs to be assessed separately through detailed study.  相似文献   

Post-Cyclone Sidr nutritional status of women and children in coastal Bangladesh: an empirical study     

Shitangsu Kumar Paul  Bimal Kanti Paul  Jayant K. Routray 《Natural Hazards》2012,64(1):19-36

Cyclone Sidr, a Category 4 storm, struck the southwestern coast of Bangladesh on November 15, 2007, causing 3,406 deaths, 2.51 million acres of crop damage, and aggregated damage of US$1.7 billion. It significantly damaged household food availability and increased post-cyclone nutritional insecurity. This study assesses the nutritional status of household and explores influences of various socioeconomic variables on nutritional security. More specifically, it explores the impact of the cyclone on short-term nutritional status of women of reproductive age and children under 5?years. For this study, 331 households living in three villages devastated by Cyclone Sidr were selected. The nutritional status of women of reproductive age was measured based on body mass index, and that of children aged 6?C59?months was measured based on weight-for-height (wasting), height-for-age (stunting), and weight-for-age (underweight). This study found that the nutritional status, along with other household characteristics, of the study groups was not remarkably different across the three selected villages. Findings of this study further suggest that the nutritional security situation was not much changed in the post-cyclone period compared with the pre-cyclone period primarily because of rapid and effective distribution of essential food items among cyclone survivors by the government of Bangladesh along with donor and other organizations. However, nutritional insecurity was more prevalent in the island village relative to inland and coastline villages. Similarly, fishermen were found to be the most vulnerable to nutritional insecurity in the post-cyclone period. Several recommendations are made to improve food aid distribution in the aftermath of a cyclone.  相似文献   

Exploring probable reasons for record fatalities: the case of 2011 Joplin, Missouri, Tornado   总被引：1，自引：1，他引：0  

Bimal Kanti Paul  Mitchel Stimers 《Natural Hazards》2012,64(2):1511-1526

On the evening of 22 May 2011, an EF-5 tornado tore a path six miles long across Joplin, Missouri, USA, killing 162 people as it passed through the heart of the city. This tornado stands as the deadliest single tornado to hit the United States since modern recordkeeping began in 1950, surpassing the tornado of 8 June 1953 that claimed 116 lives in Flint, Michigan. The record number of deaths caused by the single tornado in Joplin was far higher than the average annual number of US tornado deaths over the last three decades. This study explores the reasons for the high number of fatalities caused by the 2011 Joplin tornado. Questionnaire surveys administered among tornado survivors and informal discussions with emergency management personnel and others suggest that five reasons are associated with the high number of tornado fatalities experienced in Joplin: (1) the sheer magnitude of this event; (2) its path through commercial and densely populated residential areas; (3) the relatively large size of damage area; (4) the physical characteristics of affected homes in Joplin; and (5) the fact that some residents ignored tornado warnings. Several recommendations are offered, the implementation of which should reduce future tornado fatalities not only in Joplin, but elsewhere in the United States.  相似文献   

A New Blastability Index for Hard Roof Management in Blasting Gallery Method     

Chhangte Sawmliana  Pijush Pal Roy 《Geotechnical and Geological Engineering》2012,30(6):1357-1367

The presence of hard and massive sandstone above the coal seam in underground coal mines often leads to delay in caving of overlying rock beds thereby causing excessive load on supports and posing danger to underground workings. The problem is more prominent in blasting gallery (BG) as well as longwall mining methods in Indian coal mines. Induced caving by blasting is a promising means for hard roof management in underground coal mines. Based on extensive studies and data collected from different mines in India, a Blastability Index (BI) has been developed which can be used for the classification of roof according to the degree of ease in caving by induced blasting. Different charge factors have also been suggested based on the Blastability Index. Due to wide change in the method of extractions, ??Cavability Index?? for longwall panel was found ineffective in case of BG method of working as well as bord and pillar working. For this reason, this proposed Blastability Index would be of immense help for caving of hard roof by induced blasting.  相似文献   

Bioavailability of arsenic in the soil horizon: a laboratory column study     

Sudip Jyoti Sahu  Bibhash Nath  Sharmi Roy  Biswapati Mandal  Debashis Chatterjee 《Environmental Earth Sciences》2012,65(3):813-821

Groundwater contaminated with arsenic (As), when extensively used for irrigation, causes potentially long-term detrimental effects to surface soils. Such contamination can also directly affect human health when irrigated crops, such as rice, vegetable and fruits, are used for human consumption. Therefore, an understanding of the leaching behavior of As in surface soils is of high importance, because such behavior may increase the bioavailability of As in the soil horizon. In this study, we have investigated the role of phosphate ions in leaching and bioavailability of As in the soil horizon, where drinking groundwater contains elevated levels of As (≥50 μg/L). Soil and groundwater samples were characterized in the laboratory and measured for physical and chemical constituents. The soils are generally neutral to slightly alkaline in character (pH range 7.5–8.1) with low to moderate levels of free Fe₂O₃, Al₂O₃, CaCO₃, organic carbon, and clay content. The measured electrical conductivity (mean 599 μS/cm) of the soils demonstrates their non-saline nature. The Eh values (range −37 to −151 mV) of the groundwater indicate anoxic condition with low to moderate levels of bicarbonate (range 100–630 mg/L) and phosphate (range 0.002–4.0 mg/L). The arsenic content (range 50–690 μg/L; mean 321 μg/L) in groundwater has exceeded both WHO recommended guideline values (10 μg/L) and the National safe drinking water limit (50 μg/L). Regression analyses demonstrate that the bioavailability of As in the soil horizon is mainly controlled by the composition of free Fe₂O₃ and CaCO₃ content of the soils. However, application of P could increase bioavailability of As in the soil horizon and become available to plants for uptake.  相似文献   

Strange pulsar hypothesis     

Raka Dona Ray Mandal  Monika Sinha †  Manjari Bagchi  Sushan Konar  Mira Dey ‡  Jishnu Dey 《Monthly notices of the Royal Astronomical Society》2006,365(4):1383-1386

It appears that there is a genuine shortage of radio pulsars with surface magnetic fields significantly smaller than ∼10⁸ G. We propose that the pulsars with very low magnetic fields are actually strange stars locked in a state of minimum free energy and therefore at a limiting value of the magnetic field which cannot be lowered by the system spontaneously.  相似文献