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991.
简介了注塑模内贴标成型原理、工艺和应用发展趋势,根据实际产品的应用案例分析了注塑模内贴标在塑料产品成型过程中的影响因素和工艺要点,提出了模内贴标塑料模具的特点及其设计的一般原则,分析了模内贴标产品的常见缺陷,并给出了改善措施. 相似文献
992.
Ye M Hu J Peng M Liu J Liu J Liu H Zhao X Tan W 《International journal of molecular sciences》2012,13(3):3341-3353
Aptamers are single-stranded oligonucleotides of DNA or RNA that bind to target molecules with high affinity and specificity. Typically, aptamers are generated by an iterative selection process, called systematic evolution of ligands by exponential enrichment (SELEX). Recent advancements in SELEX technology have extended aptamer selection from comparatively simple mixtures of purified proteins to whole living cells, and now cell-based SELEX (or cell-SELEX) can isolate aptamers that bind to specific target cells. Combined with nanotechnology, microchips, microfluidic devices, RNAi and other advanced technologies, cell-SELEX represents an integrated platform providing ultrasensitive and highly specific tools for clinical medicine. In this review, we describe the recent progress made in the application of cell-SELEX for diagnosis, therapy and biomarker discovery. 相似文献
993.
Xing-wu Tan Bai-mu Wang Ye Wang Shu-zhong Zhan 《Inorganic chemistry communications》2010,13(9):1061-1063
The Mannich reaction of 2-aminoethanol, 2-tert-butyl-4-methylphenol, and formaldehyde at the ratio sets of 1:2:2 provided a new ligand, N-(1-ethanol)-N,N-bis(3-tert-butyl-5-methyl-2-hydroxybenxyl)amine (H3L). In the presence of base, H3L reacted with FeCl3·6H2O to form a dinuclear Fe(III) complex [Fe2L2] 1. The value of μeff at room temperature (5.95 μB), is much less than the expected spin-only value (8.37 μB) of two high spin (hs) Fe3+ (S = 5/2) ions [μ = g[∑ ZS(S + 1)]1/2], indicating there were strong interactions between Fe3+ ions. The effective magnetic moment (μeff) decreased abruptly with cooling to a minimum value of 0.1 μB at 2 K. It was worth noting that Fe3+ ions of 1 exhibited thermally induced quartet ? doublet spin transitions, and these transitions were abrupt. The magnetic behaviors of 1 denoted the occurrence of intramolecular anti-ferromagnetic interactions. J (? 13.58 cm? 1) agrees with the result from Gorun–Lippard equation, ? J (cm? 1) = Aexp(BP(Å) = 12.9). 相似文献
994.
Dietary Inclusion of Tea Catechins Changes Fatty Acid Composition of Muscle in Goats 总被引:1,自引:0,他引:1
This study was conducted to examine dietary tea catechins (TC) supplementation on the fatty acid composition of muscle and
ruminal bacteria in goats fed a maize stover-based diet. Forty goats, 8 months old (16.2 ± 1.2 kg), were randomly divided
into four equal groups (10 animals in each group) and assigned to four experiment diets with TC supplementation at four levels
(0, 2,000, 3,000 and 4,000 mg TC/kg feed, namely TC0, TC2000, TC3000 and TC4000, respectively). After a 60-day feeding period,
all the goats were slaughtered and sampled. The results showed that dietary TC inclusion increased the average daily gain
(ADG), protein content in the semimembranosus muscle and dry matter in the longissimus dorsi muscle (LD). Dietary TC supplementation increased the ratio of n-6 to n-3 fatty acid, the ratio of polyunsaturated fatty
acids to saturated fatty acids was higher in TC3000 and TC4000 than in TC0 and TC2000 for LD. The current results implied
that dietary inclusion of a suitable TC dose could improve the growth performance and increase the proportions of unsaturated
fatty acids in muscle, and the biohydrogenation of ruminal microorganisms might change the profiles of fatty acids in the
muscle of growing goats. 相似文献
995.
Gang Wang Zhentao Wang Wei Wang Rujie He Kaixuan Gui Caiwang Tan Wei Cao 《Ceramics International》2019,45(8):10223-10229
In this paper, brazing behaviors between ZrB2SiC and Ti6Al4V by Cu foam interlayer were studied. The microstructure, formation mechanism, mechanical property and fracture surface of the joints were systematically studied. The results showed that the phases in the joints were α+β-Ti, TiCu, Ti2Cu, Cu(s, s), TiC, TiB2 and Ti3SiC2. An optimum shear strength reached up to 435??MPa?at a brazing temperature of 910?°C and holding time of 20?min. Such a shear strength was 90?MPa higher than the one without the Cu foam. The obtained high shear strength of joint was discussed from microstructure and residual stress. With the increase of brazing time, Cu(s,s) gradually disappeared and the content of Ti2Cu intermetallic compound increased, which was harmful for the joint. Furthermore, the residual stress of joint with Cu foam was calculated to be 324?MPa, lower than the one without Cu foam interlayer. 相似文献
996.
997.
铜铁试剂(CUP)—示波计时电位法直接测定天然水和饮用水中的铝含量。在0.5 mol/L(NH_4)_2SO_4-NH_3·H_2O(pH值=5.4)缓冲溶液中,加入铝后,铝—CUP配合物切口电位为-1.20V,切口深度在7.2×10~(-7)~3.2×10~(-5)mol/LAl范围内有线性关系,检测下限为5.8×10~(-7)mol/L。在2.0×10~(-5)mol/L时相对标准偏差为5.1(n=10)。应用该法测定了天然水和饮用水中铝含量,并同ICP/AES所获结果进行了对照。结果基本一致。 相似文献
998.
Multi-objective optimization of net energy, external costs of environment pollutant-emissions, and cost of using cassava-based fuel ethanol as an alternative automotive fuel in Guangxi has been conducted based on its holistic life cycle, from feedstock production to fuel combustion. A new indicator, cost of net energy (CNE), linking net energy-yield, external cost of environment pollutant-emissions, and production cost (the lower the CNE reading, the better the total performance) of ethanol–gasoline blends, is proposed for carrying out multi-objective optimization. On the life-cycle basis, CNE of ethanol–gasoline blends is found to obtain its lowest value, i.e. 0.119 RMB/MJ, when processing fuel during the ethanol conversion stage was natural gas and the ratio of ethanol blended with gasoline was 5%. From the standpoint of the CNE indicator, the most viable implement form of cassava-based fuel ethanol should be used as one of oxygenate additives. The recommended processing fuel during ethanol conversion stage should be natural gas. 相似文献
999.
通过对发动机活塞实际工作温度场分布规律与冷却特点的分析,提出了以激光作为热源,应用能量分配与光学转换技术模拟再现活塞温度场分布及热负荷作用的试验方法.研究结果表明该方法对活塞顶部不同区域温度可控,瞬态温度模拟真实,损伤监测到位,试验效率高.为今后开展活塞热损伤,热疲劳机理研究及提高活塞热负荷评估试验的置信度奠定了基础. 相似文献
1000.
Xiuxia Meng Xun Gong Yimei Yin Nai-Tao Yang Xiaoyao Tan Zi-Feng Ma 《International Journal of Hydrogen Energy》2013
YSZ/NiO-YSZ dual-layer hollow fibers with a thin YSZ top layer integrated on a porous NiO-YSZ (60:40 in weight) support, have been developed by one step method via a co-spinning-sintering process. Hydrogen reduction was performed to form YSZ/Ni-YSZ micro tube as the half solid oxide fuel cells (SOFCs). The microstructure of the dual-layer hollow fibers was tailored by adding ethanol as non-solvent in the initial mixture dopes for NiO-YSZ anode spinning. LSM cathode containing 20 wt%-YSZ was deposited on the electrolyte surface by dip-coating method to fabricate micro-tubular SOFCs. Experimental results indicate that the dual-layer hollow fibers from the anode dopes containing 15–20 wt% of ethanol possess the desired microstructure with optimized properties, such as the bending strength of 180 MPa, the porosity of 38–35% and the conductivity of 3000 S cm−1 at room temperature. The micro-tubular SOFCs fabricated from such hollow fibers show a maximum power density up to 485 mW cm−2 at 850 °C with 20 mL min−1 of H2 as fuel and 30 mL min−1 air as oxidant, respectively. 相似文献