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1.
The influence of different referencing methods on the accuracy of δ13C value measurement of ethanol fuel by gas chromatography/combustion/isotope ratio mass spectrometry 下载免费PDF全文
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Donato Pocar Pasqualina Trimarco Gabriella Bombieri 《Journal of heterocyclic chemistry》1998,35(3):687-692
Pyrolysis of 4-aryl-5-amino-v-triazolines affords, generally, amidines and/or benzanilides. Pyrolysis of 4-aryl-5-morpholino-v-triazolines 6 , together with the expected amidines 7 and/or aryanilides 8 , produced the morpholinopyrroles 9 . The reaction mechanism of this unusual transformation is discussed. Influence of solvent dipole moment in pyrrole formation is suggested. Pyrrole 9a [i.e. 2-(3-morpholin-4-yl-2,4-pyrrol-1-yl)-benzonitrile] has been fully characterized and its molecular structure has been determined by X-ray diffraction analysis. 相似文献
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M. A. Macrì C. Del Gratta L. Di Donato S. Di Luzio G. L. Romani S. Della Penna A. Pasquarelli 《Il Nuovo Cimento D》1994,16(5):425-432
Summary A preliminary study is here reported on a new potential marker for biomagnetic measurements. The marker consists of superparamagnetic
polymer microspheres which were detected in the presence of external steady magnetic fields by means of an r.f.-SQUID magnetometer.
The particles were prepared in samples differing in the concentration value and immersed in a homogeneous magnetic field of
variable intensity. A simple model was taken into account for the distribution of the microspheres in the samples, so that
the theoretical values were compared to the marker field values measured by the biomagnetic sensor. The overall sensitivity
of the experimental apparatus and the minimum concentration value of the marker were then estimated. 相似文献
6.
We consider the Abelian gauge theory related to the interaction between the solitary waves of the nonlinear Klein-Gordon equation
and the electromagnetic field. We analyze the existence of electromagnetostatic solutions and, in particular, of vortices.
Dedicated to the memory of Professor Aldo Cossu 相似文献
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The periodic unfolding method was introduced in 2002 by D. Cioranescu et al. for the study of classical periodic homogenization. In this Note, we extend this method to perforated domains introducing also a boundary unfolding operator. As an application, we study the homogenization of some elliptic problems with Robin condition on the boundary of the holes. To cite this article: D. Cioranescu et al., C. R. Acad. Sci. Paris, Ser. I 342 (2006). 相似文献
9.
利用精密自动绝热热量计直接测定了配合物Zn(Phe)(NO3)2·H2O(s) (Phe:苯丙氨酸)在78-370 K温区的摩尔热容. 通过热容曲线的解析得到该配合物的起始脱水温度为, T0=(324.27±0.37) K. 将该温区的摩尔热容实验值用最小二乘法拟合得到摩尔热容(Cp, m)对温度(T)的多项式方程, 并且在此基础上计算出了它的舒平热容值和各种热力学函数值. 依据Hess定律, 通过设计热化学循环, 选择体积为100 mL浓度为2 mol·L-1 的盐酸作为量热溶剂, 利用等温环境溶解-反应热量计分别测定混合物{ZnSO4·7H2O(s)+2NaNO3(s)+L-Phe(s)}和{Zn(Phe)(NO3)2·H2O(s)+Na2SO4(s)}的溶解焓为, ⊿dH0m,1 =(69.42±0.05) kJ·mol-1, ⊿dH0 m,2 =(48.14±0.04) kJ·mol-1, 进而计算出该配合物的标准摩尔生成焓为, ⊿fH0m =-(1363.10±3.52) kJ·mol-1. 另外, 利用紫外-可见(UV-Vis)光谱和折光指数(refractiveindex)的测量结果检验了所设计的热化学循环的可靠性. 相似文献
10.
Alessandro D' Aprano Dorina Ines Donato Antonio Carrubba Doctor in Chemistry thesis of A. Carrubba 《Journal of solution chemistry》1983,12(3):209-220
Conductance measurements are reported for LiPi, NaPi, KPi, RbPi, CsPi, Bu4NPi, Bu4NBr, Bu4NClO4, Bu4NNO3, and Bu4NBBu4 at 25°C in -butyrolactone-sulfolane mixtures. In these mixtures of solvents that are practically homomorphous, isodielectic and with comparable dipole moments, the ion pair association and ionic mobilities of large ions conform to the expectations of the primitive model. Electrolytes containing lithium or sodium ions show anomalies indicating that other factors besides shape, dipole moment, and polarizability of the solvent molecules are involved in the association and transport processes of these ions. 相似文献