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991.
Single crystals of inorganic–organic hybrid compounds, M5(OH)2[CO2(CH2)2CO2]4 [M = Mn(Mn-s), Fe(Fe-s), Co(Co-s), Mn/Fe(Mn---Fe-n) and Mn/Co(Mn---Co-n)] were prepared under hydrothermal condition at 180 °C from a mixture of transition metal(II) chlorides, succinic acid, potassium hydroxide, and water. Crystal structure of all compounds present the same structural type in the single-crystal X-ray diffraction refinements and X-ray powder diffraction analysis. The single crystal structural analyses for three homo-metallic compounds were performed and the prepared compounds have divalent metal ions on the basis of bond valence sum calculations. The unit cell constants for the hetero-metallic compounds, e.g., Mn/Fe, Mn/Co solid solutions were determined. Magnetic measurements show that the Mn-s may have antiferromagnetic interaction at low temperature. The Fe-s and the Co-s compounds have ferrimagnetic coupling below 10 K. The Mn---Co-n compounds show the ferromagnetic magnetic behavior while the Mn---Fe-n compounds present antiferromagnetic ordering. 相似文献
992.
Aluminum phthalocyanine (AlPc) in the presence of Ph3PO acts as a highly effective catalyst for cyanosilylation of various aldehydes to the corresponding cyanohydrin trimethylsilyl ethers. The reaction proceeds smoothly with 5 mol% catalyst loading at room temperature, giving up to 96% yield. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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994.
In this paper, we define the v-finiteness for a length function Lv on the set of all v-ideals of an integral domain R and show that R is a Krull domain if and only if every proper integral v-ideal of R has v-finite length and Lv((AB)v)=Lv(A)+Lv(B) for every pair of proper integral v-ideals A and B in R. We also give Euclidean-like characterizations of factorial, Krull, and π-domains. Finally we define the notion of quasi-∗-invertibility and show that if every proper prime t-ideal of an integral domain R is quasi-t-invertible, then R is a Krull domain. 相似文献
995.
Young Hwan Han Byoung Cheol Lee Young Kyung Lim Young Uk Jeong Seong Hee Park Cheol Jin Lee Tae Jae Lee 《Radiation Physics and Chemistry》2007,76(11-12):1783-1786
We fabricated a prototype of an e-beam irradiator which is low energy and diode type by using sprayed double walled carbon nanotubes (DWCNTs). The diode type e-beam irradiator consisted of a grounded e-beam window which was made of thin Havar foil and a negatively charged cathode where carbon nanotubes were sprayed on titanium coated aluminum rod. Synthesized DWCNTs which were purified through the chemical processes and then mixed with ethanol were sprayed several hundred times on the surface area of 2×300 mm2. A phosphor screen located on the e-beam window and a CCD camera was used to observe the emitted electron beams directly from the cathode to the air with an increase of the voltage. The measured e-beam current was 1.5 mA at −95 kV. 相似文献
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Transition Metal Chemistry - A series of Zn(II) complexes bearing camphor-based ethyleneamine derivatives, [LnZnCl2]... 相似文献
1000.
Weijia Zheng Kyung‐Hee Yoo Jeong‐Min Choi Da‐Hee Park Seong‐Kwan Kim Young‐Sun Kang A. M. Abd El‐Aty Ahmet Hacmüftüolu Jing Wang Jae‐Han Shim Ho‐Chul Shin 《Biomedical chromatography : BMC》2019,33(1)
In the present study, we aimed to develop a reliable screening method based on liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS) for the detection and quantification of naproxen, methyltestosterone and 17α‐hydroxyprogesterone caproate residues. The target analytes were extracted from samples of eel, flatfish and shrimp using acetonitrile with 1% acetic acid, followed by liquid–liquid purification with n‐hexane. Chromatographic separation was achieved on a reversed‐phase analytical column using 0.1% formic acid containing 10 mm ammonium formate in distilled water (A) and methanol (B) as mobile phases. All the matrix‐matched calibration curves were linear (R2 ≥ 0.99) over the concentration range of the tested analytes. Recovery at three spiking levels (0.005, 0.01 and 0.02 mg/kg) ranged from 68 to 117% with intra‐ and inter‐day precisions <10%. Five market samples for each matrix (eel, flatfish and shrimp) were collected and tested for method application. In summary, the proposed method is feasible to screen and quantify the analytes with high selectivity in aquatic food products meant for human consumption. 相似文献