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The crystal and molecular structure of the title complex has been determined. The space group isP21/n, witha=8.460(3),b=8.503(3),c=20.341 (8) Å,=98.41(3) andZ=2. The ligand molecules chelate the CuII such that the metal has a tetragonally distorted octahedral geometry; four N atoms occupy the equatorial plane and two H2O molecules occupy the axial positions. The average Cu-N and Cu-O distances are 2.005(6) and 2.47(1) Å, respectively. The novel ligand, 1,1-dimethyl-2,2-diimidazolylsulfide was formedin situ from a methanolic solution of copper(II) sulfate pentahydrate and 1-methylimidazole-2-thiol. The measured spectral parameters (visible, EPR, and photoelectron spectroscopy) correlate well with the molecular structure.  相似文献   
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Background  

There is great interest in appropriate phenotypes that serve as indicator of genetically transmitted frontal (dys)function, such as ADHD. Here we investigate the ability to deal with response conflict, and we ask to what extent performance variation on response interference tasks is caused by genetic variation. We tested a large sample of 12-year old monozygotic and dizygotic twins on two well-known and closely related response interference tasks; the color Stroop task and the Eriksen flanker task. Using structural equation modelling we assessed the heritability of several performance indices derived from those tasks.  相似文献   
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Background  

In the field of auditory neuroscience, much research has focused on the neural processes underlying human sound localization. A recent magnetoencephalography (MEG) study investigated localization-related brain activity by measuring the N1m event-related response originating in the auditory cortex. It was found that the dynamic range of the right-hemispheric N1m response, defined as the mean difference in response magnitude between contralateral and ipsilateral stimulation, reflects cortical activity related to the discrimination of horizontal sound direction. Interestingly, the results also suggested that the presence of realistic spectral information within horizontally located spatial sounds resulted in a larger right-hemispheric N1m dynamic range. Spectral cues being predominant at high frequencies, the present study further investigated the issue by removing frequencies from the spatial stimuli with low-pass filtering. This resulted in a stepwise elimination of direction-specific spectral information. Interaural time and level differences were kept constant. The original, unfiltered stimuli were broadband noise signals presented from five frontal horizontal directions and binaurally recorded for eight human subjects with miniature microphones placed in each subject's ear canals. Stimuli were presented to the subjects during MEG registration and in a behavioral listening experiment.  相似文献   
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Ferrocene and nickelocene have pseudo-isomorphous structures at room temperature but only ferrocene undergoes a second-order phase transformation on cooling. Calculation and analysis of appropriate lattice-energy surfaces as a function of concerted ring rotation showed that ferrocene has a disordered structure at room temperature different from nickelocene which exhibits a single minimum in the lattice-energy function. The results readily suggest a mechanism for the ferrocene phase transformation. The correct low-temperature structure is predicted only after taking intramolecular interactions into account.  相似文献   
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