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11.
建立了4个平行的SBR处理合成废水,游离氨(FA)浓度分别为0.5、5、10、15 mg/L,命名为S0.5、S5、S10和S15,4个系统的脱氮性能在整个实验过程中均很好(平均值为98.7%),利用FA对亚硝酸氧化细菌(NOB)的抑制作用,结合过程控制,成功在S10和S15系统中实现短程硝化.在建立短程硝化途径的过程... 相似文献
12.
Cristiana Tanase Ana Maria Enciu Elena Codrici Ionela Daniela Popescu Maria Dudau Ana Maria Dobri Sevinci Pop Simona Mihai Ancua-Augustina Gheorghian-Gleanu Mihail Eugen Hinescu 《International journal of molecular sciences》2022,23(2)
Glioblastoma (GBM) is one of the most aggressive tumors of the central nervous system, characterized by a wide range of inter- and intratumor heterogeneity. Accumulation of fatty acids (FA) metabolites was associated with a low survival rate in high-grade glioma patients. The diversity of brain lipids, especially polyunsaturated fatty acids (PUFAs), is greater than in all other organs and several classes of proteins, such as FA transport proteins (FATPs), and FA translocases are considered principal candidates for PUFAs transport through BBB and delivery of PUFAs to brain cells. Among these, the CD36 FA translocase promotes long-chain FA uptake as well as oxidated lipoproteins. Moreover, CD36 binds and recognizes thrombospondin-1 (TSP-1), an extracellular matrix protein that was shown to play a multifaceted role in cancer as part of the tumor microenvironment. Effects on tumor cells are mediated by TSP-1 through the interaction with CD36 as well as CD47, a member of the immunoglobulin superfamily. TSP-1/CD47 interactions have an important role in the modulation of glioma cell invasion and angiogenesis in GBM. Separately, FA, the two membrane receptors CD36, CD47, and their joint ligand TSP-1 all play a part in GBM pathogenesis. The last research has put in light their interconnection/interrelationship in order to exert a cumulative effect in the modulation of the GBM molecular network. 相似文献
13.
利用87C51对FPGA实现被动串行配置 总被引:1,自引:0,他引:1
基于静态随机存储器(SRAM)的可重配置可编程逻辑器件(PLD),因其独特的优点,已在电子系统开发中占据了重要的位置,但如何以最低的工业成本完成自动配置,成为可重配置可编程逻辑器件在电子系统开发中的一个难题。本文以ACEX1K50为例,介绍利用87C51FA单片机对其进行被动串行配置的原理,给出软硬件实现的方法;可嵌入到系统中自动完成配置,实现其功能。 相似文献
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15.
在厌氧条件下研究了西南地区一种典型土壤微生物芽孢杆菌Bacillus sp.dwc-2对模拟地下水中U(Ⅵ)的还原行为,重点考察了时间、无机阴离子、腐殖酸(HA)及富里酸(FA)对还原的影响,并利用TEM、EDS、SAED和XPS对还原后的样品进行了表征。结果表明:在pH=7.0、cNaHCO3=5 mmol/L和T=303 K条件下,Bacillus sp.dwc-2对U(Ⅵ)的还原率随时间的增加而增加,24 h内最大还原率为12.2%,此后则随时间的增加逐渐降低;HA和FA对U(Ⅵ)的微生物还原行为有一定影响,其中HA和FA浓度为25 mg/L时,U(Ⅵ)的还原在24 h最明显,其还原率分别为14.2%和16.2%,但随着HA和FA浓度的继续增加,因在U(Ⅵ)离子与HA、FA形成的配合物表面形成致密的腐殖层,抑制了电子的转移,阻止了U(Ⅵ)的还原。此外,研究表明HCO3-也会抑制U(Ⅵ)的还原。TEM-SAED和XPS分析证实了还原过程中U(Ⅳ)的存在。上述结果可为真实环境中微生物还原U(Ⅵ)提供基础数据和参考。 相似文献
16.
Amy Richards Chakra Wijesundera Phil Salisbury 《Journal of the American Oil Chemists' Society》2008,85(2):159-168
The effects of genotype and growing environment on the tocopherols and fatty acids (FA) of experimental Brassica juncea and B. napus breeding lines were investigated. For both species, with the exception of a few genotypes, the concentration ratio of γ-tocopherols
to α-tocopherol was practically constant. The genotype influenced the tocopherol concentration in B. napus, and to a lesser degree, B. juncea. The environment also had a similar effect, and a positive correlation existed between the daily maximum temperature and
the α-tocopherol concentration in B. napus. Genotype effects on the FA composition were significant for the conventional but not for Clearfield or triazine tolerant
traits of B. napus. The genotype had no effect on the FA of the B. juncea genotypes. In contrast, the growing environment had a significant influence on the FA composition of both species with apparent
influence from temperature and rainfall. For both species, the concentration of γ-tocopherol as well as total tocopherols
was inversely related to the 18:3 concentration, which could have resulted from opposite and independent effects of temperature
on the two variables. No relationship existed between the concentrations of tocopherol and the remaining unsaturated FA 18:1
and 18:2. The positional distribution of unsaturated FA within the oil triacylglycerol was a function of their total concentration. 相似文献
17.
采用氯化钙/甲酸(CaCl2/FA)溶解体系对丝素进行溶解,讨论不同CaCl2质量分数对丝素溶解性的影响,通过流变、SEM、红外光谱以及X衍射等测试手段表征丝素溶液及其干燥膜的结构特征。结果表明:在相同温度、溶解时间条件下,丝素的溶解度随着CaCl2质量分数的增加而增加,溶解呈现先快后缓的上升趋势;当CaCl2质量分数为2%、5%、8%、10%时,丝素溶液的流变曲线中剪切黏度随剪切速率的增大先增加后减小,CaCl2质量分数为1%时,黏度明显高于其他质量分数值溶解下的丝素溶液。通过SEM可清晰地观察到丝素溶液以及丝素干燥膜中的纳米纤维结构。红外光谱分析表明,该溶解体系制备的丝素蛋白大分子以β-折叠结构为主,而CaCl2质量浓度的不同对丝素的结构影响不明显。X衍射分析表明,丝素在9.5°、20.5°和23.9°处出现结晶峰,均属于Silk II结构。 相似文献
18.
Kensuke Konishi Jun-Ichi Toyooka Kenji Kamiyama Ikken Sato Shigenobu Kubo Shoji Kotake Kazuya Koyama Alexander D. Vurim Valery A. Gaidaichuk Alexander V. Pakhnits Yuri S. Vassiliev 《Nuclear Engineering and Design》2007,237(22):2165-2174
The WF (wall failure) test of the EAGLE program, in which 2 kg of uranium dioxide fuel-pins were melted by nuclear heating, was successfully conducted in the IGR (Impulse Graphite Reactor) of NNC/Kazakhstan. In this test, a 3 mm-thick stainless steel (SS) wall structure was placed between fuel pins and a 10 mm-thick sodium-filled channel (sodium gap). During the transient, fuel pins were heated, which led to the formation of a fuel-steel mixture pool. Under the transient nuclear heating condition, the SS wall was strongly heated by the molten pool, leading to wall failure. The time needed for fuel penetration into the sodium-filled gap was very short (less than 1 s after the pool formation). The result suggests that molten core materials formed in hypothetical LMFBR core disruptive accidents have a certain potential to destroy SS-wall boundaries early in the accident phase, thereby providing fuel escape paths from the core region. The early establishment of such fuel escape paths is regarded as a favorable characteristic in eliminating the possibility of severe re-criticality events. A preliminary interpretation on the WF test results is presented in this paper. 相似文献
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20.
介绍了如何在兼容ARM V4指令集的32位RISC处理器(FA526)所构建的SoC平台上(即FIE8100),运用智原科技所提价的FA526-Linux开发包通过armboot装载Linux操作系统。使开发人员可以在基于FIE8100 SoC的仿真平台-MediaCreative!在进行二次开发和验证的设计方法。 相似文献