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71.
The hexane-soluble fractions of hydroliquefied products from three Yallourn brown coal lithotypes have been separated into five fractions by combined silica-alumina packed column chromatography. Analyses of various fractions by g.c.-m.s. permitted the identification of ≈50 components in the saturate fraction and 40 components in the diaromatic fraction, together with 30 components in the monoaromatics. The components identified were quite similar among hexane-soluble portions of all three lithotypes. A marked predominance of even carbon number alkane (C23-C29) was observed in the hydrocarbon fractions from pale lithotype over , and medium light lithotype over both pure ZnCl2 and . However, medium dark lithotype over both melt catalysts produced a saturate fraction with an odd carbon number(C22-C28) preference. Based on spectral methods, Soxhlet extracts obtained from untreated lithotypes (hexane and benzene solubles) were characterized as complex mixtures of higher molecular weight(300–1000) aliphatic hydrocarbons, which were supposed to be a precursor of the saturates produced from the corresponding lithotype in the catalytic hydroliquefaction. 相似文献
72.
Investigated the functional significance of male gerbil scent-marks in 4 experiments with 60 male and female Mongolian gerbils. In Exps I and II, males in a novel test environment marked more, groomed more, and urinated less in the presence of odors of a strange male than in their absence. Female odors elicited male marking more than did male odors. In Exps III and IV, females were selectively less aggressive toward familiar-smelling males in comparison with unfamiliar-smelling males. These results, in conjunction with field observations of related species, call into question the hypothesis that gerbil scent-marks function territorially and instead suggest that the primary targets are adult females. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
The limitations of wind tunnel testins, particularly for chimneys with a circular cross-section are discussed. The use of data from full-scale observations and wind tunnel tests at high Reynolds numbers in conjunction with suitable mathematical models are suggested to obtain wind load and wind response estimates that offer a higher level of reliability than wind tunnel estimates. 相似文献
74.
ES el Daly 《Canadian Metallurgical Quarterly》1998,53(2):87-93; discussion 93-5
There are three ways to approach and resect the caudate lobe of the liver, that is; and isolated caudate lobectomy, a combined resection of the liver overlying the caudate lobe, and a transhepatic anterior approach by splitting parenchyma of the liver. We had two patients with neoplasms originating in the caudate lobe who underwent a complete caudate lobectomy. Both patients have been doing well without liver dysfunction. Although after the transhepatic anterior approach we anticipated an adverse effect from splitting the parenchyma of the liver, the postoperative course was uneventful and similar to that of the right side approach. 相似文献
75.
76.
Chemical force spectroscopy (CFS) is becoming a powerful technique with which to measure intermolecular forces. The prime advantage over other techniques is the ability to map spatial distribution of ligands on the surface. We have used CFS to explore the binding force of a variety of different chiral molecules in order to understand more about the nature of what is a fundamental aspect of chemical biology and of central importance in pharmacology. 相似文献
77.
78.
Trevor Shaw 《Coloration Technology》1998,114(9):241-246
Council directive 96/61/EC on integrated pollution prevention and control was agreed by the Council of the European Union on 24 September 1996. It will have far reaching effects on industrial installations throughout the European Union. This paper summarises the directive's provisions and attempts to predict its impact on wool textile wet processors. The actions being taken by trade associations to ensure that the guidelines are fair and reasonable are also reviewed. 相似文献
79.
Zhuoqi Tang David Furniss Nigel C. Neate Trevor M. Benson Angela B. Seddon 《Journal of the American Ceramic Society》2019,102(1):195-206
A systematic investigation is presented, for the first time, of a 1000 ppmw (parts per million, by weight) Dy3+-doped Ge–As–Ga–Se chalcogenide glass series, with a fixed low Ga content of 1 atomic% (at. %), suitable for active mid-infrared fiber optics. Seven glasses constitute the series, which have increasing average coordination number from 2.49 to 2.61, in steps of 0.02, with the GeSe2, As2Se3, and Ga2Se3 stoichiometries kept. Glass formation is confirmed using X-ray diffraction and differential scanning calorimetry. Fourier transform infrared spectroscopy is reported for the series. Parallel plate viscometry enables prediction of fiber-drawing temperatures and, with differential thermal analysis, determines the potential for fiber fabrication. X-ray diffraction of samples after parallel-plate viscometry shows that Ge25As9Ga1Se65 (at. %) alone, in the glass-series, devitrifies to form the single-crystalline phase: monoclinic-GeSe2; scanning electron microscope imaging suggests that this phase is both surface and bulk grown. Overall, the recommended host glass at. % compositions for doping with rare-earth ions and drawing to active mid-infrared fiber are: Ge17.5As18Ga1Se63.5, Ge15As21Ga1Se63, and Ge12.5As24Ga1Se62.5. 相似文献
80.
Christopher R Fellin Steven M Adelmund Dylan G Karis Ryan T Shafranek Robert J Ono Cecilia G Martin Trevor G Johnston Cole A DeForest Alshakim Nelson 《Polymer International》2019,68(7):1238-1246
We describe the synthesis, characterization and direct‐write 3D printing of triblock copolymer hydrogels that have a tunable response to temperature and shear stress. In aqueous solutions, these polymers utilize the temperature‐dependent self‐association of poly(alkyl glycidyl ether) ‘A’ blocks and a central poly(ethylene oxide) segment to create a physically crosslinked three‐dimensional network. The temperature response of these hydrogels was dependent upon composition, chain length and concentration of the ‘A’ block in the copolymer. Rheological experiments confirmed the existence of sol–gel transitions and the shear‐thinning behavior of the hydrogels. The temperature‐ and shear‐responsive properties enabled direct‐write 3D printing of complex objects with high fidelity. Hydrogel cytocompatibility was also confirmed by incorporating HeLa cells into select hydrogels resulting in high viabilities over 24 h. The tunable temperature response and innate shear‐thinning properties of these hydrogels, coupled with encouraging cell viability results, present an attractive opportunity for additive manufacturing and tissue engineering applications. © 2018 Society of Chemical Industry 相似文献