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991.
Copolymers of aniline and toluidine were synthesized by oxidative chemical polymerization using different ratios of the monomers in the feed, and characterized by a number of techniques including UV–visible, IR, Raman, 1H NMR and EPR spectroscopies, as well as by thermogravimetric analysis and conductivity measurements. The properties of the copolymers are influenced by the amount of toluidine in the copolymer. Poly(o‐toluidine) and poly(m‐toluidine) are noticeably different in their solubility and conductivity. The copolymers show better solubilities than polyaniline but have lower conductivities. Differences in the properties of the salt and base forms of the copolymers are pointed out. Copyright © 2003 Society of Chemical Industry 相似文献
992.
C. Laurino P. Laurienzo M. Malinconico M. Scoponi A. Sorrentino P. Vacca M. G. Volpe 《应用聚合物科学杂志》2004,93(1):23-29
Innovative polymeric films based on blends of nylon 6 and ethylene‐co‐vinyl alcohol, previously tested by contact with the simulating fat‐containing foods, were further tested as packaging for fresh minced meat. As quality attributes for the shelf‐life evaluation, the microbiological parameters and some chemical–physical parameters were chosen. The changes that occurred during the evaluation period of 6 days were monitored by several means on both the polymer films and the fresh meat. The results suggest that the barrier properties of the polymeric films were shown to play a determinant role in the lipid oxidation, thus confirming the previous evaluation of the simulating foods. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 23–29, 2004 相似文献
993.
1. Introduction Hydroprocessing catalysts based upon the transitionmetal sulfides (TMS) have been widely used for about70 years. In the early period, some metal compoundssuch as Co, Ni, Mo and W sulfides and their mixtureswere believed to be the most a… 相似文献
994.
995.
Y. Soong A. G. Blackwell R. R. Schehl M. F. Zarochak J. A. Rayne 《Chemical Engineering Communications》1995,138(1):213-224
An ultrasonic technique is under development for measuring solids concentration in a three-phase slurry reactor. Preliminary measurements have been made on slurries consisting of water, glass beads, and air bubbles. The data show that both the sound speed and attenuation are well-defined functions of both the solid and gas concentrations in the slurries. A simple model is proposed to correlate the solids concentration with the measured ultrasonic signals. 相似文献
996.
Hariharan Ramalingam Bhuvana Sowrirajalu Anuradha Ganesan Sarojadevi Muthusamy 《Polymer International》2004,53(10):1442-1447
A new type of diamine monomer containing the anisyl moiety was synthesized via a straight‐forward one‐step procedure. Anisaldehyde was reacted with 2,6‐dimethylaniline in the presence of dry HCl to attain bis(4‐amino‐3,5‐dimethylphenyl)anisylmethane. A series of organo‐soluble polyimides were prepared using the anisyl diamine and various aromatic dianhydrides via a two step method involving thermal imidization. All polyimides are soluble in strong polar solvents such as N‐methyl‐2‐pyrollidone, N,N‐Dimethylformamide, and N,N‐DimethylAcetamide. The polyimides show excellent thermal stability and good mechanical properties. The glass transition temperatures of the polyimides are in the range 265–294 °C. The tensile strengths are in the range 79–99 MPa and the temperatures at which 10 % weight loss occurs are in the range 460–496 °C. Copyright © 2004 Society of Chemical Industry 相似文献
997.
Concept development of an underground research tunnel for validating the Korean reference HLW disposal system 总被引:5,自引:0,他引:5
Sangki Kwon W.J. Cho P.S. Han 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2006,21(2):203-217
In order to dispose of high-level radioactive waste (HLW) safely in geological formations, it is necessary to assess the feasibility, safety, appropriateness, and stability of the disposal concept at an underground research laboratory (URL) constructed in the same geological formation as the host rock. In this study, minimum requirements and the conceptual design for an efficient construction of a small scale URL were derived based on a literature review. To confirm the validity of the conceptual design for construction at KAERI, a geological survey including a seismic refraction survey, electronic resistivity survey, borehole drilling, and in situ and laboratory tests were carried out. The mechanical stability of the URL was investigated with a consideration of the surface topography, tunnel geometry, tunnel slope, sequential excavation, in situ stress ratio, erosion effect, and rock property variation along the tunnel using the three-dimensional code, FLAC3D. From the study, it was possible to conclude that the small scale URL will be effectively constructed in a granite mass at KAERI and will satisfy the minimum requirements. 相似文献
998.
999.
Properties of individual fractions of detonation nanodiamond 总被引:1,自引:0,他引:1
I. Larionova V. Kuznetsov A. Frolov O. Shenderova S. Moseenkov I. Mazov 《Diamond and Related Materials》2006,15(11-12):1804
Detonation nanodiamonds synthesized and purified on an industrial scale were additionally purified and separated into narrow size fractions by centrifugation. The average particle size for the smallest fraction was lower than 30 nm and the yield was about 20 wt.%. Using FTIR spectra analysis, it was demonstrated that ND aggregates of different sizes, separated from the same pristine ND, have different surface compositions of active surface groups, particularly oxygen-containing groups, which finally influence their zeta potential values and hydrosol stability. Using DTA analysis, the higher reactivity of the smallest fractions during heat treatment in air was also demonstrated. 相似文献
1000.
GAO Hong-xia YU jian-zu XIE Yong-qi 《半导体光子学与技术》2006,12(1):43-46
In order to meet the electrical and thermal performance requirements of current high performance optoelectronics, two package types with dual-in-line package(DIP) and ball grid array(BGA) for optoelectronics are modeled and thermally simulated, their thermal characterizations are compared and discussed by using the temperature contours and the simulated heating characterization curves in free air and forced air ambient. The results show that BGA has superior inside and outside total performances, and has the promising future in the highly integrated optoelectronics. 相似文献