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排序方式: 共有1106条查询结果,搜索用时 15 毫秒
61.
对提高果奶稳定性的方法研究表明,果奶必须含有0.4%-1.2%的油酯,PH值为3.7-4.0,温度为50-80℃,单宁含量低于0.3%,均质压力为18-25MPa,在加酸成果汁前后各均质一次,对果奶的稳定效果好。乳化剂和络合剂须与奶粉同时溶解,并经胶体磨充分乳化后再加入稳定剂。当均质后的料液温度低于40℃时,剧烈搅拌并缓缓加入稀释的果汁或酸,在65-70℃杀菌30min。按上述工艺生产的果奶和芒果 相似文献
62.
Conjugated polymers and indium arsenide-based nanocrystals were used to create near-infrared plastic light-emitting diodes. Emission was tunable from 1 to 1.3 micrometers--a range that effectively covers the short-wavelength telecommunications band--by means of the quantum confinement effects in the nanocrystals. The external efficiency value (photons out divided by electrons in) is approximately 0.5% (that is, >1% internal) and is mainly limited by device architecture. The near-infrared emission did not overlap the charge-induced absorption bands of the polymer. 相似文献
63.
A common onc gene sequence transduced by avian carcinoma virus MH2 and by murine sarcoma virus 3611 总被引:17,自引:0,他引:17
N C Kan C S Flordellis G E Mark P H Duesberg T S Papas 《Science (New York, N.Y.)》1984,223(4638):813-816
A common cellular sequence was independently transduced by avian carcinoma virus MH2 (v-mht) and murine sarcoma virus (MSV) 3611 (v-raf). Comparison of the nucleotide sequences of v-mht and v-raf revealed a region of homology that extends over 969 nucleotides. The homology between the corresponding amino acids was about 95 percent with only 19 of 323 amino acids being different. With this example, 5 of the 19 known different viral onc genes have been observed in viruses of different taxonomic groups. These data indicate that (i) the number of cellular proto-onc genes is limited because, like other viruses of different taxonomic groups, MH2 and MSV 3611 have transduced the same onc gene-specific sequences from different cell species and (ii) that specific deletion and linkage of the same proto-onc sequences to different viral vector elements affect the oncogenic potential of the resulting viruses. The difference in transformation capabilities of MH2 and MSV 3611 serves as an example. 相似文献
64.
Identification of HTLV-III/LAV sor gene product and detection of antibodies in human sera 总被引:24,自引:0,他引:24
N C Kan G Franchini F Wong-Staal G C DuBois W G Robey J A Lautenberger T S Papas 《Science (New York, N.Y.)》1986,231(4745):1553-1555
The nucleotide sequence of the genome of HTLV-III, the infectious agent etiologically associated with the acquired immune deficiency syndrome, predicts a small open reading frame, termed sor, located between the pol and env genes. A DNA segment containing 82 percent of the sor region was inserted into a prokaryotic expression vector, pJL6, to determine whether sor encodes a viral protein and to gain some insight into its possible function. The bacterially synthesized sor protein reacted with sera from individuals infected with HTLV-III, indicating that sor is expressed as a protein product or products that are immunogenic in vivo. Antibodies to the purified, bacterially synthesized sor protein were found to react specifically with the same protein and also with a protein of molecular weight 23,000 (23K) in HTLV-III-infected H9 cell extracts. The 23K protein comigrated with a protein immunoprecipitated by the serum of a hemophiliac patient with antibodies to HTLV-III, suggesting that this protein is probably the sor gene product. 相似文献
65.
Wang Z Carter JA Lagutchev A Koh YK Seong NH Cahill DG Dlott DD 《Science (New York, N.Y.)》2007,317(5839):787-790
At the level of individual molecules, familiar concepts of heat transport no longer apply. When large amounts of heat are transported through a molecule, a crucial process in molecular electronic devices, energy is carried by discrete molecular vibrational excitations. We studied heat transport through self-assembled monolayers of long-chain hydrocarbon molecules anchored to a gold substrate by ultrafast heating of the gold with a femtosecond laser pulse. When the heat reached the methyl groups at the chain ends, a nonlinear coherent vibrational spectroscopy technique detected the resulting thermally induced disorder. The flow of heat into the chains was limited by the interface conductance. The leading edge of the heat burst traveled ballistically along the chains at a velocity of 1 kilometer per second. The molecular conductance per chain was 50 picowatts per kelvin. 相似文献
66.
辜堪生 《河南科技大学学报(农学版)》2001,21(1):45-47,60
分析了经济转型时期国企职工的主人翁地位失落的原因,提出了国有企业保障企业职工主人翁地位的措施:充分保证和利用职代会来实现企业的民主管理,很好地利用工会这一企业职工的群众性组织。 相似文献
67.
化归方法是数学解题中的一个重要方法。本文从思维方法的角度论述了化归方法的基本含义,探讨化归方法在数学解题中的应用。 相似文献
68.
树干曲率的自动测量是智能立木整枝机作业的重要步骤.该文针对立木图像的特点,提出了一种基于计算机视觉的立木树干曲率自动测量方法.该方法包含4个主要步骤:利用阈值分割对树干图像进行提取,得到图像的粗分割;在中值滤波的基础上,利用拉普拉斯算子对图像进行边缘位置点的检测,从而得到准确而连续的边缘;利用数学形态学方法对树干边缘进行细化处理;以道格拉斯-普克法提取树干曲线上的特征点,对其进行曲线拟合并求得树干曲率.实验结果表明,该方法能比较准确地识别树干的弯曲度. 相似文献
69.
70.
本研究选用了埋植CIDR栓法、埋植PRID栓法、PG法以及PMSG+PG法四套方案对西藏41头母牦牛进行了超数排卵试验。试验结果:埋植CIDR法得到的平均卵母细胞数为7.4枚/头,埋植PRID法得到的平均卵母细胞数为6.5枚/头,PG法得到的平均卵母细胞数为4枚/头,PMSG+PG法得到的平均卵母细胞数为4.8枚/头,各组之间差异极显著(P<0.01);而经过卵母细胞成熟培养之后,埋植CIDR法得到的平均可用卵母细胞数为6.2枚/头,埋植PRID法得到的平均可用卵母细胞数也为6.2枚/头,PG法得到的平均可用卵母细胞数为4枚/头,PMSG+PG法得到的平均可用卵母细胞数为4.6枚/头,CIDR+FSH法与PRID+FSH法两组、两次PG法与PMSG+PG法两组差异不显著(P>0.05),但是CIDR+FSH法和PRID+FSH法组与两次PG法和PMSG+PG法组之间差异都极显著(P<0.01);用CIDR法和PRID法进行西藏牦牛超排效果较好,并可获得较多的可用卵母细胞。 相似文献