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191.
Ashis Bhattacharjee Haradhan Mandal Madhusudan Roy Joachim Kusz Wolfgang Hofmeister 《Environmental monitoring and assessment》2013,185(10):8673-8683
This paper deals with the physical nature of the fly ashes obtained from two thermal power plants, situated in West Bengal, India. The fly ash samples are characterized by using comprehensive techniques with an emphasis on their ultrafine nature. The particle sizes of the samples are estimated using scanning electron microcopy (SEM) and found to lie within 0.18–5.90 μm. For morphology and compositional analysis, we also use SEM coupled with energy dispersive X-ray spectrometry. From X-ray study of the fly ashes the nature of conglomeration is seen to be crystalline, and the major components are mullite (Al6Si2O13) and quartz (SiO2). The magnetic measurement of the fly ash samples was carried out by SQUID magnetometer. 57Fe Mössbauer spectra are obtained using a conventional constant-acceleration spectrometer with a 57Co/Rh Mössbauer source. The hyperfine parameters obtained, in general, support the findings as made from XRD analysis and provide a quantitative measure of different iron ions present in the samples. The paper presents experimental data on the physical aspects of the fly ash samples of the thermal power plants which comprise coarse, fine, and ultrafine magnetic particulate materials and attempts to provide an exhaustive analysis. 相似文献
192.
Bernd Lengers Inga Schiefler Wolfgang Büscher 《Environmental monitoring and assessment》2013,185(12):9751-9762
The overall measurement of farm level greenhouse gas (GHG) emissions in dairy production is not feasible, from either an engineering or administrative point of view. Instead, computational model systems are used to generate emission inventories, demanding a validation by measurement data. This paper tests the GHG calculation of the dairy farm-level optimization model DAIRYDYN, including methane (CH4) from enteric fermentation and managed manure. The model involves four emission calculation procedures (indicators), differing in the aggregation level of relevant input variables. The corresponding emission factors used by the indicators range from default per cow (activity level) emissions up to emission factors based on feed intake, manure amount, and milk production intensity. For validation of the CH4 accounting of the model, 1-year CH4 measurements of an experimental free-stall dairy farm in Germany are compared to model simulation results. An advantage of this interdisciplinary study is given by the correspondence of the model parameterization and simulation horizon with the experimental farm’s characteristics and measurement period. The results clarify that modeled emission inventories (2,898, 4,637, 4,247, and 3,600 kg CO2-eq. cow?1 year?1) lead to more or less good approximations of online measurements (average 3,845 kg CO2-eq. cow?1 year?1 (±275 owing to manure management)) depending on the indicator utilized. The more farm-specific characteristics are used by the GHG indicator; the lower is the bias of the modeled emissions. Results underline that an accurate emission calculation procedure should capture differences in energy intake, owing to milk production intensity as well as manure storage time. Despite the differences between indicator estimates, the deviation of modeled GHGs using detailed indicators in DAIRYDYN from on-farm measurements is relatively low (between ?6.4 % and 10.5 %), compared with findings from the literature. 相似文献
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For 25 years the conception has been well established that the overwhelming majority of chemical elements and their isotopes have been synthesized in stars during the course of stellar evolution, in particular during the advanced stages and in supernova explosions. Until now this general idea has not led to major difficulties or inconsistencies. On the contrary, the theoretical models have been very successful in explaining the observed abundances in meteorites, planets (including the earth), stars (including the sun) and galactic cosmic rays. Our present understanding of nucleosynthesis will be reviewed with special attention given to nucleosynthetic processes in primordial stars and supernovae. We will concentrate primarily on predictions which can be made for relative abundances rather than for absolute abundances, because the latter problem requires evolutionary models of the galaxy which are beyond the scope of this article. 相似文献
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Anya Vollpracht Wolfgang Brameshuber 《Environmental science and pollution research international》2010,17(5):1177-1182
Objective
In this paper, results regarding the leaching of trace elements out of mineral building materials under irrigation are presented. 相似文献199.
Elaine Tweneboah Lawson Wolfgang Schluchter Chris Gordon 《Journal of Coastal Conservation》2010,14(3):231-238
Like many developing countries, Ghana is grappling with environmental issues, such as the degradation of coastal natural resources.
In an attempt to ameliorate the current state of affairs, broad institutional arrangements and policy interventions have been
put in place. However coastal natural resources are still being overexploited and the effects of this are felt more strongly
by certain groups (such as women and the rural poor) than others. This has led to the argument pointing to an urgent need
to include local resource users as active participants in environmental decision making and to incorporate their environmental
values in the management of coastal natural resources. Using empirical data from women in two Ghanaian coastal communities,
this paper highlights the importance of exploring how the environmental attitudes and values of women might be considered
in the management of local coastal natural resources. It assesses effectiveness of the paired comparison methodology in this
respects and how this method can be also used to prioritise their environmental concerns. The results show that in both areas
respondents place the greatest importance on the coastal natural resources as sources of wealth creation and of food, values
which are often described as being “anthropocentric”. The paper thus argues that having discovered that the ecological value
placed on natural resources is low, initiatives that could win the support of people would be those that link the livelihood
and wellbeing to coastal NRM. It emphasizes the fact that conservation cannot exist outside of people and social systems;
nor will it succeed unless they are linked to the welfare of resource users. 相似文献
200.
Bernhard G. Zimmermann Simon Grill Wolfgang Holzgreve Xiao Yan Zhong Laird G. Jackson Sinuhe Hahn 《黑龙江环境通报》2008,28(12):1087-1093
Recent reports have indicated that digital PCR may be useful for the noninvasive detection of fetal aneuploidies by the analysis of cell-free DNA and RNA in maternal plasma or serum. In this review we provide an insight into the underlying technology and its previous application in the determination of the allelic frequencies of oncogenic alterations in cancer specimens. We also provide an indication of how this new technology may prove useful for the detection of fetal aneuploidies and single gene Mendelian disorders. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献