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31.
Reaction of the two-coordinate 'assembling complex-ligand' [Cu(tn)]2+ with the building block [Cr(CN)6]3- leads to a unique two-dimensional Cu-Cr cyano-bridged ferromagnet with unusual mu 3- and mu 4-bridging [Cu(tn)]2+ units.  相似文献   
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The preparation and characterization of the four stereoisomeric trans-geranyl farnesylacetates I–IV are described. Their structure and configuration were identified by mode of formation, elemental analyses, IR. spectra, and particularly by PMR. spectra.  相似文献   
35.
G. Pala  E. Crescenzi  G. Bietti 《Tetrahedron》1970,26(24):5789-5791
5,7,12,13-Tetrahydro-6H-dibenz[c,g]azonine (I), a novel tricyclic system, was synthesized by three different routes. Besides the threefold mode of formation, the structure of I was determined on the basis of analytical and spectral evidence.  相似文献   
36.
Electrochemically monoreduced [M(R,R'timdt)(2)](-) dithiolenes, showing unprecedented wavelength selective photoconducting properties in the third optical fiber window (1500-1800 nm), fine-tunable through modifications in the chemical structure, allowed for the fabrication of a test photodetector with a bit rate of about 85 kbit s(-1).  相似文献   
37.
Chemistry laboratory simulators have not been worth consideration until the CD-ROM came along with its wonderful capacities. Corel, [1] a well-known name in software has realized this. Their new ChemLab CD-ROM has excited some interest among chemistry teachers. This review examines the contents of this CD-ROM, rates the effectiveness of its experiments, and suggests who might profit from the use of such a simulator for the traditional chemistry laboratory.  相似文献   
38.
Summary Daily samples of airborne particulates (143) were collected along the year in La Spezia (Italy). Seasonal variations of atmospheric PAH concentrations, with highest winter values, have been observed. The concentration of PAHs was found to correlate negatively with the mean ambient temperature during the sampling period. Volatilization, photodegradation and seasonal modifications of emissions from urban traffic were found to be a possible explanation of this phenomenon.  相似文献   
39.
A new polynuclear copper(II) complex [Cu7(OH)6Cl2(pn)6(H2O)2](C(CN)3)4Cl2 with hydroxo-bridging ligands has been prepared; the centrosymmetric cluster cation can be described as two Cu4O3Cl distorted cubane units sharing one copper cation.  相似文献   
40.
NR+ is a highly effective vitamin B3 type supplement due to its unique ability to replenish NAD+ levels. While NR+ chloride is already on the market as a nutritional supplement, its synthesis is challenging, expensive, and low yielding, making it cumbersome for large-scale industrial production. Here we report the novel crystalline NR+ salts, d/l/dl-hydrogen tartrate and d/l/dl-hydrogen malate. Their high-yielding, one-pot manufacture does not require specific equipment and is suitable for multi-ton scale production. These new NR+ salts seem ideal for nutritional applications due to their bio-equivalence compared to the approved NR+ chloride. In addition, the crystal structures of all stereoisomers of NR+ hydrogen tartrate and NR+ hydrogen malate and a comparison to the known NR+ halogenides are presented.  相似文献   
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