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151.
Z.Y. Tan X.F. Xu S.L. Sun C. Zhou Y.H. Ao H.X. Zhang Y. Han 《Polymer Engineering and Science》2006,46(10):1476-1484
A series of acrylonitrile–butadiene–styrene (ABS) with different rubber content were prepared by diluting ABS grafting copolymer containing 60% rubber with a styrene–acrylonitrile copolymer. ABS prepared were blended with bisphenol‐A‐polycarbonate (PC) at the ratio of 70/30, 50/50, and 30/70 to prepare PC/ABS blends. Influence of rubber content in ABS on the properties of ABS and PC/ABS blends were investigated. PC/ABS blends with different compositions got good toughness when the rubber in ABS increased to the level that ABS itself got good toughness. The tensile properties and processability of PC/ABS blends decreased with the increase of the total rubber content introduced into the blends. ABS with the rubber content of 30 wt% is most suitable to be used to prepare PC/ABS blends. The rubber content in ABS affected the viscosity of ABS, and subsequently the viscosity ratio of PC to ABS. As a result, the morphology of PC/ABS blends varied. The increase of rubber content in ABS results in finer structure of PC/ABS blends. POLYM. ENG. SCI. 46:1476–1484, 2006. © 2006 Society of Plastics Engineers. 相似文献
152.
Cytological identification of soybean mitotic metaphase chromosomes (2n = 40) has been severely limited by their small size and uniform karyomorphology. We have developed fluorescent in situ hybridization (FISH), PCR-primed in situ labelling (PCR-PRINS) procedures, and molecular probes for routine cytological identification and for the physical mapping of soybean somatic chromosomes. Chromosome preparation has been achieved by modifications of previous protocols and through the preparation of root-tip protoplasts prior to chromosome spreading. Initially our probe selection focused on highly repeated DNAs that provide very intense localized hybridization signals. Repetitive gene probes that have proven valuable include the rDNA loci (5S and 45S) which are chromosome specific. We have also developed satellite DNA probes for two different sequence families: the SB92 and the STR120 satellites. Both of these are tandemly arranged at multiple chromosomal loci. By using different cloned examples of each family, we have been able to selectively label unique subsets of soybean chromosomes. Double hybridization with biotin and digoxigenin labeled probes has allowed us to determine the chromosomal overlap between different probes. In addition, we have joined portions of the metaphase chromosome painting patterns with the genetic map by single-copy FISH and PCR-PRINS detection of the RFLP loci G8.15, G17.3, and A199a and A199b. Total genomic DNA in situ hybridization (GISH) patterns were also used to characterize the soybean chromosomes. 相似文献
153.
论文概述了费索干涉仪型激光波长计的原理和标定。详细分析了环境温度变化使仪器参数发生微小变化;论述了SIOM-01激光波长计以一种新颖的将标准激光引入测量光路的方法,随时对仪器参数实行单点标定,克服了由环境温度变化引进的测量误差。 相似文献
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156.
Compressive and tribological properties of Al2O3 fibre and hexagonal BN particle hybrid reinforced Al-Si alloys 总被引:6,自引:0,他引:6
Al2O3 fibre-hexagonal BN particle hybrid reinforced aluminium-silicon alloys were fabricated by centrifugal force infiltration route. Hardness test and ultimate compressive test results are reported. The wear and friction properties of hybrid MMCs was investigated by means of a block-on-ring (bearing steel) type wear rig in a dry sliding condition. It is shown that the hardness and ultimate compressive strength of hybrid MMCs was evidently decreased with the addition of hexagonal BN particles, however, the wear rate and coefficient of friction of hybrid MMCs was improved simultaneously with increase of BN particle volume fraction, especially for the higher applied loads in the test. 相似文献
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159.
Songhua Xu Haisheng Tan Xiantao Jiao Francis C.M. Lau Yunhe Pan 《Computer Graphics Forum》2007,26(3):609-618
We propose a generic pigment model suitable for digital painting in a wide range of genres including traditional Chinese painting and water-based painting. The model embodies a simulation of the pigment-water solution and its interaction with the brush and the paper at the level of pigment particles; such a level of detail is needed for achieving highly intricate effects by the artist. The simulation covers pigment diffusion and sorption processes at the paper surface, and aspects of pigment particle deposition on the paper. We follow rules and formulations from quantitative studies of adsorption and diffusion processes in surface chemistry and the textile industry. The result is a pigment model that spans a continuum from the very wet to the very dry brush stroke effects. We also propose a new pigment mixing method based on machine learning techniques to emulate pigment mixing in real life as well as to support the creation of new artificial pigments. To experiment with the proposed model, we embedded the model in a sophisticated digital brush system. The combined system exhibits interactive speed on a modest PC platform. http://www.cs.hku.hk/~songhua/pigment provides supplementary materials for this paper. 相似文献
160.
Efficient encoding of IEEE 802.11n LDPC codes 总被引:1,自引:0,他引:1
Addressed is the issue of LDPC coding for the emerging IEEE 802.11n standard. An efficient encoding algorithm is proposed. The algorithm is simple and easy to implement. The memory requirement is trivial 相似文献