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101.
The human chromosome 9 displays the highest degree of structural variability. Four different types of variants are described including pericentric inversion, extra G-positive band in the q arm, additional G-positive band in the p arm and duplication of band 9q21-q22. It is important to demonstrate inheritance from a phenotypically normal individual in order to differentiate between a variant chromosome and an abnormal chromosome.  相似文献   
102.
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   
103.
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   
104.
介绍了1-氨基蒽醌生产方法及革新工艺,对150t/a精馏法生产1-氨基蒽醌的效益进行了计算。并浅谈了其重要衍生产品溴氨酸。  相似文献   
105.
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   
106.
107.
Efficient encoding of IEEE 802.11n LDPC codes   总被引:1,自引:0,他引:1  
Cai  Z. Hao  J. Tan  P.H. Sun  S. Chin  P.S. 《Electronics letters》2006,42(25):1471-1472
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   
108.
通过诱变筛选得到一株具有高活性L-Asp-β-脱羧酶的菌株PseudomonasNX-1,对该株酶形成和酶反应的条件进行了详细研究,该株可以高效地转化L-Asp生成L-AIa,转化4~5山每L培养液可转化L-Asp量高达1400g左右,生成L-Ala浓度高达90%以上,摩尔转化率近100%。  相似文献   
109.
本文在全面阐述鞍山市水资源现状的基础上,系统地分析了鞍山市供水系统存在的问题,并针对鞍山实际情况,提出了保障鞍山市城市饮水安全的相关研究及对策。  相似文献   
110.
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