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161.
The mechanical and thermal expression (MTE) process can be used to remove the moisture from high moisture coal such as lignite
by applying the thermal energy and mechanical force. The moisture content of lignite at Yallourn, VIC, Australia is around
60–70%. Two-third of the water from the lignite can be removed at 150°C and 5.1 MPa by this process. In the conventional drying
process, moisture is driven off by evaporation when the lignite passes through the mill. This process is inefficient from
a thermodynamic point of view, because the latent heat of evaporation has to be supplied from the hot flue gas. This paper
presents computational fluid dynamics (CFD) investigation of fluid flow and combustion of conventional lignite and MTE lignite
in a tangentially fired full-scale industrial furnace. The idea is to investigate the aerodynamics and combustion effect of
using MTE lignite in existing furnaces. The furnace investigated was Yallourn stage-2 in Victoria, Australia. CFD software
CFX-4 (User Guide, CFX-4–Solver. AEA Technology. Harwell Laboratory, Oxfordshire, 1997) was used in this investigation. The
MTE process is under development and has not been used in the real power station for the commercial production of electricity,
hence no experimental data is available for comparison with the numerical predictions. To gain confidence in the MTE lignite
simulations, the temperature contours and oxygen concentration at different furnace level of the conventional lignite combustion
were validated first against the available experimental data. Then the predicted results of MTE lignite combustion were compared
with conventional lignite combustion to assess the possibility of burning MTE lignite in existing tangentially fired furnaces. 相似文献
162.
Naser A. Anjum Sarvajeet S. Gill Armando C. Duarte Eduarda Pereira Iqbal Ahmad 《Journal of nanoparticle research》2013,15(9):1-26
Silver nanoparticles (AgNPs) have broad spectrum antimicrobial/biocidal properties against all classes of microorganisms and possess numerous distinctive physico-chemical properties compared to bulk Ag. Hence, AgNPs are among the most widely used engineered NPs in a wide range of consumer products and are expected to enter natural ecosystems including soil via diverse pathways. However, despite: (i) soil has been considered as a critical pathway for NPs environmental fate, (ii) plants (essential base component of all ecosystems) have been strongly recommended to be included for the development of a comprehensive toxicity profile for rapidly mounting NPs in varied environmental compartments, and (iii) the occurrence of an intricate relationship between “soil–plant systems” where any change in soil chemical/biological properties is bound to have impact on plant system, the knowledge about AgNPs in soils and investigations on AgNPs–plants interaction is still rare and in its rudimentary stage. To this end, the current paper: (a) overviews sources, status, fate, and chemistry of AgNPs in soils, AgNPs-impact on soil biota, (b) critically discusses terrestrial plant responses to AgNPs exposure, and (c) illustrates the knowledge-gaps in the current perspective. Based on the available literature critically appraised herein, a multidisciplinary integrated approach is strongly recommended for future research in the current direction aimed at unveiling the rapidly mounting AgNPs-fate, transformation, accumulation, and toxicity potential in “soil–plant systems,” and their cumulative impact on environmental and human health. 相似文献
163.
Naser Ghotbadini-Bahraman Ali Sheibani M. Reza Shishehbore 《International Journal for Ion Mobility Spectrometry》2017,20(1-2):41-45
In this study, a methodology has been described for the determination of chlorpyrifos pesticide residue in pistachio oil based on a quick, easy, cheap, effective, rugged and safe (QuEChERS) sample preparation with combined ion mobility spectrometry (IMS). The different parameters that could influence the QuEChERS- IMS for chlorpyrifos analysis were optimized. Under optimum conditions, the linear dynamic range was obtained over 0.4 to 20 μg g?1 with R 2 = 0.997 and precision as relative standard deviation was 7.1%. The limits of detection and quantification were 0.1 and 0.3 μg g?1 of chlorpyrifos, respectively. The recovery results of chlorpyrifos were at an acceptable range (average 78.3–92.3). 相似文献
164.
A new one-pot, multicomponent condensation reaction of aldehydes, 2-naphthol, and 1-acylthiosemicarbazides is described as an efficient method for the synthesis of novel 4-substituted 1-acylthiosemicarbazides in the presence of p-toluenesulfonic acid (p-TSA) as a catalyst under two conditions: organic solvent and solvent-free media. The present procedure offers several advantages, such as good yields, low cost, and very easy workup. 相似文献
165.
Naser Beyraghi Abdollah Khoei Khayrollah Hadidi 《Analog Integrated Circuits and Signal Processing》2014,80(3):473-481
In this paper a CMOS current-mode analog multiplier circuit based on a novel current-mode squarer circuit is proposed. The circuit is simulated using HSPICE simulator and designed in 0.35 µm standard CMOS technology with ± 1.5 V supply voltage. The simulation results of proposed multiplier for input current range of ±10 μA demonstrate a ?3 dB bandwidth of 24.5 MHz, 475 μW as maximum power consumption, nonlinearity of 1.3 % and a THD of 0.87 % at 1 MHz. 相似文献
166.
Sulforaphane is a cognate isothiocyanate of glucoraphanin, released by degradation of glucosinolate through myrosinase enzyme, when Brassica tissues are crushed or chewed. C8 analytical column and mixture of water/acetonitrile 65/35 (ν/ν) as mobile phase were used to separate sulforaphane in broccoli tissues (e.g., 7‐day‐seedling, seed, floret and leave). Confirmation of sulforaphane in crude extract of broccoli tissues was monitored using gas chromatography‐mass spectroscopy (GC‐MS). The highest amount of sulforaphane (1216 μg/g dry weight) found in 7‐day‐seedling. This method is suitable for routine screening of plant materials and proposes a low cost and robust technique for the analysis of sulforaphane. 相似文献
167.
Batool M Martin TA Naser MA George MW Macgregor SA Mahon MF Whittlesey MK 《Chemical communications (Cambridge, England)》2011,47(40):11225-11227
Time-resolved IR (TRIR) studies on (η(5)-C(5)H(4)Me)Mn(L)(CO) (L = 1,3-diethyl-4,5-dimethylimidazol-2-ylidene, PPh(3)) indicate that the rate of reaction with CO is ca. 10(2) slower for the N-heterocyclic carbene intermediate, which DFT calculations suggest is due to the presence of a strong MnH-C agostic bond. The reactivity of these intermediates in alkane solvents is governed by such interactions rather than solvent coordination to the unsaturated metal centre. 相似文献
168.
Akbar Mobinikhaledi Naser Foroughifar Somayeh Faghihi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1837-1842
Treatment of 2-aminopyridine ( 1 ) with chloroacetyl chloride in dry benzene gave 2-chloro-N-(pyridin-2-yl)acetamide ( 3 ), which on further reaction with potassium thiocyanate gave 2-imino-3-(pyridin-2-yl)thiazolidin-4-one ( 4 ) as an intermediate compound for the synthesis of pyridin-2-yl substituted 2-imino-thiazolidine-4-one derivatives. Cyclocondensation reaction of ( 4 ) with a series of aromatic aldehydes gave 5-arylidene derivatives of pyridin-2-yl substituted 2-imino-thiazolidine-4-ones 5a–j . 1 H and 13C NMR spectroscopy, as well as elemental analyses, were used for the identification of these new compounds. 相似文献
169.
Manawwer Alam Naser M. Alandis Fahmina Zafar Eram Sharmin Yasser M. Al-Mohammadi 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10):698-708
AbstractVegetable oil based environmentally friendly polyurethane-TiO2 nanocomposite coatings have been synthesized by using sunflower oil derived diol, toluene diisocyanate and TiO2 nanoparticles. The chemical structure was confirmed by FTIR and NMR techniques while physico-chemical testing was carried out by standard laboratory methods. Physico-mechanical and anticorrosive tests of the coatings (in different corrosive media) have been investigated by standard methods. In addition to this the morphology and thermal stability behavior of the coatings have been carefully investigated by different techniques like XRD, TEM, TGA/DTG and DSC. The comparison of the performance of nanocomposites with the respective virgin polyurethane coatings reveals that the dispersion of nanoTiO2 enhanced the mechanical, corrosion and thermal stability behavior of the polymer. The synthesized nanocomposites can be used safely upto 250–275?°C. These sunflower oil derived polyurethane nanocomposites can be used in the world of protective coatings, as an alternative of petroleum derived corrosion protective coating materials. 相似文献
170.
AbstractPoly(vinylidene fluoride)-based nanocomposite films with different loadings of PMMA-modified graphene sheets were prepared by a solution-mixing and solvent casting method. The prepared films were annealed at three different temperatures and the crystalline structures of the samples were investigated. X-ray diffraction data confirmed the PMMA-modified graphene nanosheets enhanced the preferential β-crystalline structure when increasing the annealing temperature to 90?°C, while increasing the annealing temperature to 120?°C led to a β → γ phase conversion. The tendency of the graphene sheets to restack by increasing the annealing temperature was confirmed by XRD. The PMMA-modified graphene sheets, however, didn’t showa nucleating effect on the PVDF crystallizationduring DSC cooling scans. 相似文献