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101.
The objectives of this investigation were to determine the effects of coal preparation on the properties of Run-of-Mine (ROM) and washed Powhatan and Ireland Mine coals and to assess the potential effects on SRC-II liquefaction yields. The effect of washing on the two coals was found to be quite similar. For both coals, the properties were altered more significantly by changes in separation media gravity than by changes in the coal size. The elemental composition of the Powhatan and Ireland washed coals was correlated with carbon content. It was shown that both the hydrogen and oxygen levels increased linearly with the carbon content of the coal samples. However, the and ratios were not changed significantly by coal cleaning. Only small variations in the nitrogen and organic sulphur levels were observed while the sulphate sulphur and chlorine levels were not affected by coal cleaning. The major impact of the coal cleaning was to reduce the pyritic sulphur (and hence the total sulphur) content of the coals. Most of the pyritic sulphur was shifted into the middling coal and refuse fractions while the clean coals had much lower contents and the pyritic sulphur level decreased with increasing carbon content. Coal cleaning did not significantly alter the maceral contents of vitrinite, exinite, total reactive macerals (TRM), or the reflectance of vitrinite; all these parameters varied over a very narrow range, probably within the precision of the measurement technique. 相似文献
102.
A modular, parametric vibratory feeder: a case study for flexible assembly tools for mass customization 总被引:3,自引:0,他引:3
A new class of parametric and modular flexible tools is proposed to improve the setup times of assembly lines. The methodology is especially effective in dealing with problems of mass customization. In addition to improvements in the setup time, the methodology, MPATS (modular, parametric assembly tool sets) has other potential advantages such as lower tooling costs as well as faster tooling lead times compared to conventional assembly systems utilizing custom made tools. To demonstrate the feasibility of the methodology, a prototype tool set is designed and presented in this paper. The prototype tool set focuses on the most common of feeding and orienting tools: vibratory bowl feeders. 相似文献
103.
Further research is necessary to optimize the composition of flyash, clay, sand, lime, cement and moisture content to bring the project forward to production stage. The authors invite participation in the next detailed stage. 相似文献
104.
Ajay K. Jain Raj P. Singh Chand Bala 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1984,34(7):363-366
Solid membranes of copper hexacyanoferrate (III) in araldite are evaluated as a caesium ion-sensitive electrode. The electrode can be used for caesium determination in the concentration range of 10−1 to 10-4M . The potentials generated across the membrane are reproducible and steady potentials are attained in about 1 to 2min. The same electrode can be used over a period of 6 months without significant change in potential. The electrode can be used in the pH ranges 2.5–6.0 at 10−2 M Cs+ and 3.0–6.0 at 10−3 M CS+, and in presence of a number of interfering ions. Potentiometric titration of caesium nitrate with 12-moIybdophosphoric acid was also carried out using the membrane as an end point indicator. 相似文献
105.
106.
Devanand Luthria Ajay P. Singh Ted Wilson Nicholi Vorsa Gary S. Banuelos Bryan T. Vinyard 《Food chemistry》2010
Consumer awareness, pesticide and fertiliser contaminations, and environmental concerns have resulted in significant demand for organically grown farm products. The present study evaluates the influence that organic and conventional farming practices exert on the total phenolic content in eggplant samples from two cultivars, Blackbell (American eggplant) and Millionaire (Japanese eggplant), grown by conventional and organic farming practices with similar climatic conditions. In addition, plant-to-plant variation in phenolic content was determined from eight eggplant samples collected from different plants grown at various field positions. Samples were separately assayed for phenolic content by the two independent procedures, HPLC/LC–MS and Folin–Ciocalteu assay. The results of the HPLC analysis showed significant plant-to-plant variation (% RSD ranged from 22% to 48%) in 5-caffeoylqunic acid content (the most abundant phenolic acid) in eight eggplant samples collected from eight different plants belonging to the same cultivar and grown under similar conditions. The cv. Millionaire showed a higher total phenolic content compared to the Blackbell cultivar. We did not observe significant consistent trend in the phenolic content of eggplant samples grown with organic and conventional farming practices with both eggplant cultivars. We, however, observed a strong correlation (R2 = 0.87) between total phenolic content as assayed by Folin–Ciocalteu assay and 5-caffeoylqunic acid, a major phenolic acid in eggplant extract. This study concludes that multiple repetitive analyses of plant products collected from different plants grown over various time periods (seasons) at different locations should always be carried to unambiguously prove the impact of growing conditions on phenolic content or antioxidant activity. 相似文献
107.
Diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy was used to study the nature of active species in K–Rh–Co–MoS2/Al2O3 catalyst by means of probing with CO molecule. The effects of K addition to Rh and interaction between Mo and Rh were studied with varying K and Mo loadings over 1 wt% Rh/Al2O3 catalyst. In sulfided Rh–Mo/Al2O3, the formation of Rh–Mo–S phase was evidenced first time by a band at 2,095 cm?1. The introduction of Co to K–Rh–MoS2/Al2O3 catalyst showed the existence of both Rh and Co promoted MoS2 sites, but the CO absorption frequencies in DRIFT spectra are significantly at lower side compared to Co free Rh–Mo catalyst. The stabilities of CO band from Rh and Co promoted and unpromoted MoS2 sites are studied at different temperatures. When activated carbon used as support, bands for both promoted and unpromoted MoS2 sites were appeared, but the intensity of these bands were decreased largely compared to alumina based catalyst, resulted from the coverage of added K not only on the support surface but also on the active metal components due to the neutral nature of activated carbon. 相似文献
108.
Raj Pal Sharma Rajni Sharma Ajay Kumar Paloth Venugopalan Paula Brando Vitor Felix 《Inorganic chemistry communications》2009,12(10):945-947
A new cobalt(III) complex salt, [Co(NH3)6][HgBr5](1) was crystallized from a solution of hexaamminecobalt(III)bromide and potassium tetrabromomercurate(II) in aqueous medium in 1:1 molar ratio. This complex salt has been characterized by elemental analyses, spectroscopic techniques (e.g. UV/Visible, IR), solubility product and conductance measurements. The complex salt crystallizes in Orthorhombic crystal system with space group Pnma. Single crystal X-ray structure determination revealed the presence of discrete ions: [Co(NH3)6]3+ cation and a new anion [HgBr5]3−. This is the first structural report of a complex salt containing this new anion. The structure consists of stacks of cations and anions demonstrating supramolecular arrangements through N–HBr hydrogen-bond interactions. The crystal lattice is stabilized by these non-covalent interactions besides electrostatic interaction. 相似文献
109.
Copolymerization of methyl acrylate (MA) with 1‐octene (1‐Oct) was conducted in the presence of free radical initiator, 2,2′‐azobis(2‐methylpropionitrile) (AIBN) using heterogeneous Lewis acid, acidic alumina. The polymers obtained were transparent and highly viscous liquids. The copolymer composition calculated from 1H NMR showed alkene incorporation in the range of 10–61%. The monomodal nature of chromatographic curves corresponding to the molecular weight distribution in gel permeation chromatography (GPC) further confirmed that the polymers obtained are true copolymers. The number–average molecular weights (Mn) of the copolymers were in the range of 1.1 × 104–1.6 × 104 with polydispersity index of 1.75–2.29. The effects of varying the acidic alumina amount, time of polymerization, and monomer infeed on the incorporation of 1‐Oct in the polymer chain were studied. Increased 1‐Oct infeed led to its higher inclusion in the copolymer chain as elucidated by NMR. DEPT‐135 NMR spectral analysis was used to explicate the nature of arrangement of monomer sequences in the copolymer chain. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
110.
G. M. Shashidhara Devaraj Biswas B. Shubhalaksmi Pai Ajay Kumar Kadiyala G. S. Wasim Feroze M. Ganesh 《Polymer Bulletin》2009,63(1):147-157
A method commonly used to induce compatibility between polyamides and polyolefins is by chemical modification of the polyolefins.
This concept has been employed to produce compatibilized blend of nylon 6 (N6) and polypropylene copolymer (PPCP) by adding
maleic anhydride grafted polypropylene (PP-g-MAH) as a third component. The blends of N6, PPCP and PP-g-MAH were prepared
using a twin screw extruder. TEM of the blends revealed better dispersion and reduction in the size of the dispersed phase.
In case of N6 rich blends, about 25% increase in tensile strength was observed with just three phb of PP-g-MAH. The maximum
impact strength and flexural modulus were observed at around 30% PPCP. The incorporation of PP-g-MAH increased the flexural
modulus of N6/PPCP blends significantly. 相似文献