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781.
Some studies have shown that native Chinese speakers have different laterality in matched Stroop tasks from native English speakers.Recently,many imaging data,which show left laterality of English-matched Stroop interference,have been reported.And a few functional imaging studies have been conducted to investigate the phenomenon of the Chinese version of Stroop task.In this study,functional activity in the lateral prefrontal cortex of a group of normal Chinese boys with functional near-infrared imaging during a Stroop color-word task was measured to show different Stroop interferences in the prefrontal cortex.The results show obvious fluctuation of the cerebral blood volume in the right prefrontal cortex in all boys,which agrees with the finding of previous studies,that is,Chinese native boys have right laterality in their brain when the Chinese version of Stroop color-word task is applied. 相似文献
782.
Ferrimagnet is a kind of basic and important multi-sublattice magnet material. It has attracted more and more attention of physicists and mathematicians. Many results of solitons and numerical computations on this topic have appeared. In this article, the dynamic equation for an isotropic ferrimagnet with two non-equivalent sublattices is studied, existence of weak solutions in multi dimension case is proved through the penalized method, the uniqueness and smoothness of the solution in one dimension case are also obtained by the relation between this equation and hyperbolic equation. 相似文献
783.
Battery waste is one of the most destructive hazards to our environment,especially to the soil.In order to understand the effects of the battery waste on the microbial communities in soil,microcosm soils were treated with the powder made from the battery waste.Microbial biomass and respiration were measured after 15,30,45,and 60 days of the treatment,and catabolic capability and Bi- olog profile were determined after 60 days.Microbial biomass was declined by all treatments,while microbial respiration and catabolic ca- pability were enhanced.Although microbial biomass recovered after a period of incubation,microbial respiratory quotient,catabolic capa- bility and community structure remained significantly affected.Our results also suggest that microbial respiratory quotient and Biolog pa- rameters are more sensitive than microbial biomass to the battery stress on bioavailability. 相似文献
784.
盐井属于藏东昌都地区芒康县,地处于著名的三江成矿区;藏东地质构造复杂,成矿条件优越,具备形成铜、金、铅、锌、银矿的地质背景,是中国重要的多金属成矿带。根据1∶20万区域化探异常特征优选了芒康县盐井开展1∶5万地球化学测量,Au、Cu、Ag、Pb元素套叠好,异常强度大,属于典型的矿致异常,找矿前景十分广阔,是该区重要找矿靶区。 相似文献
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787.
ZHANG XianPing MA YanWei GAO ZhaoShun YU ZhengGuang WANG DongLiang WATANABE K GUO JianDong 《科学通报(英文版)》2007,52(18):2477-2480
Nano-SiC doped MgB2 tapes were prepared by the in situ powder-in-tube method. Heat treatment was performed at 650℃ for 1 h. XRD data indicate that SiC particles had reacted with the MgB2 during sintering process. MgB2 core seemed to be denser after SiC doping, and the critical temperature was slightly depressed. The critical current density Jc of the SiC doped tapes was significantly enhanced in magnetic fields up to 14 T compared to the undoped ones. For the 5% SiC doped samples, Jc was in- creased by a factor of 32 at 4.2 K, 10 T. The enhancement of Jc-B properties in SiC doped MgB2 tapes is considered to be due to the enhancement of grain linkages and the introduction of effective flux pining centers. The substitution of B by C in MgB2 grains is thought to be the main reason for the improve- ment of the flux pinning ability in SiC doped MgB2 tapes. 相似文献
788.
XI JuQun GUO Rong 《科学通报(英文版)》2007,52(19):2612-2617
Fluorescence emission spectra, FTIR spectra, zeta potential measurements, and ab initio quantum calculation are used to study the interaction between puerarin and membranes composed of egg phosphatidylcholine (PC) liposome. The hydrophobic interactions cause the puerarin molecule to partition into lipid bilayers with its B-ring, and favor the displacement of acid-base equilibrium of puerarin towards the base form. Due to the hydrogen bond formation between the puerarin hydroxyl groups and polar groups of PC molecules on the water/membrane interface, puerarin can easily intercalate into the organized structure of phospholipids and modulate the membrane function. Our results reveal that the liposome membrane integrity is significantly higher compared with that of empty liposome. 相似文献
789.
以60名非英语专业学生的作文为样本,通过统计分析作文中出现的词汇错误,试图解决三个问题:(1)确认学生在写作中所犯词汇错误类型及比例;(2)分析主要错误来源;(3)评估词汇错误的严重程度。结果表明,学生的词汇错误主要集中在词义混淆和词汇搭配。因此,笔者建议在教学中尝试利用语料库以及词汇法教学等手段,提高学生在写作中英语词汇运用的准确性与流利性。 相似文献
790.
本文在对大学生的消费结构及消费行为特征进行调查和分析的基础上,总结归纳出部分大学生消费中存在的一些问题,并提出了解决这些问题的方法与途径,强调引导大学生树立合理、适度、科学的消费观念和行为。 相似文献