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51.
52.
David Fryberger 《Foundations of Physics Letters》1990,3(4):379-386
Issues raised by W. A. Rodrigues, Jr. are discussed.1. This is not a new result; see,e.g., Rohrlich.(3)
2. A typographical error in Eq. (77) is corrected here: The productj A in the right-hand parentheses was erroneously transcribed in Ref. (2) as
A.3. I define electromagnetic fieldF = A to be that generated by electric charges and the magnetoelectric fieldG = M to be that generated by magnetic monopoles:F F +5
G.
4. Rodrigues, on the other hand, takes the position that the importance of the Lagrangian formulation should be downgraded if not discarded altogether: ... it is redundant to look for Lagrangians.(1)
5. In fact, he reformulates it using the language of differential forms.6. It is interesting to observe that this bilinear form has the additional virtue of being appropriate for dealing with the monopolecharge parity question, which was pointed out long ago.(14)
7. In fact, even mathematics looks to Nature for its authority.(16) There is evidence that Rodrigues does not understand this concept.(17) 相似文献
53.
研究了采用低场脉冲核磁共振(NMR)测定二醋酸纤维素丝束油剂的新方法,给出NMR法测定二醋酸纤维素丝束油荆含量的标准曲线。同时对NMR法测量二醋酸纤维素丝束油荆不确定度进行了评估。结果表明,NMR法具有分析速度快、无污染、无损伤和准确度高的优点,适合于二醋酸纤维素丝束油荆的分析。 相似文献
54.
A. A. Vertiy A. V. Golik A. P. Korolyuk S. I. Tarapov V. P. Shestopalov 《International Journal of Infrared and Millimeter Waves》1989,10(12):1451-1456
The research technique of amorphous magnetics is described. The paper gives the experimental data obtained by a multifunctional low-temperature radiospectrometer Buran in the mm radiowave range and presents their analysis. 相似文献
55.
Multinuclear magnetic resonance data for the title compounds are presented and discussed. The intramolecular coordination observed in the solid state is shown to be retained in solution. The best probes for the presence or absence of pentacoordination at tin are provided by the various tin-element coupling constants, although chemical shifts are in some cases also informative. A selenium-proton correlated spectrum indicated that the coupling constant 1J(Sn,Se) has a positive sign. 相似文献
56.
57.
Fa Jie Yang Da Ling Yang Shou Hai Zhang Xi Gao Jian 《中国化学快报》2007,18(8):966-968
A new interfacial polymerization (IP) procedure is developed in order to synthesize polypiperazine-amide thin-film membrane on the inner surface of poly(phthalazinone ether sulfone ketone) (PPESK) hollow fiber ultrafiltration (UF) membrane.A hollow fiber composite membrane with good performance was prepared and studied by FT-IR and scanning electron microscopy. 相似文献
58.
Suzdalev I. P. Buravtsev V. N. Maksimov Yu. V. Zharov A. A. Imshennik V. K. Novichikhin S. V. Matveev V. V. 《Russian Chemical Bulletin》2003,52(9):1950-1958
Magnetic phase transitions of the first and second order were revealed by Mössbauer spectroscopy in nanosystems of - and -ferric oxides and metallic europium subjected to shear stress (240°) under high pressure (20 kbar). For - and -ferric oxide nanoclusters, the Curie (Neel) points decreased to 300 K, whereas for nanostructured europium the Neel point increased from 90 to 100 K. The thermodynamic model of magnetic phase transitions predicting a change in the character of magnetic phase transitions and a decrease (increase) in the critical Neel (Curie) points in nanoclusters was developed. The type of magnetic phase transitions and the change in the critical points were caused by defects in nanoclusters, whose maximum concentration was observed for the clusters with the 20—50 nm size range. 相似文献
59.
D. N. Dybtsev M. P. Yutkin E. V. Peresypkina A. V. Virovets Y. Hasegawa H. Nishihara V. P. Fedin 《Russian Chemical Bulletin》2007,56(9):1782-1786
The reaction of Co(NO3)2·6H2O with 1,3,5-benzenetricarboxylic acid (H3btc, trimesic acid) in DMF at 100 °C afforded the coordination polymer [Co3(dmf)6(btc)(Hbtc)(H2btc)]··9H2O (1) (dmf is N,N′-dimethylformamide, DMF). According to the X-ray diffraction study, the metal-organic coordination polymer is composed of
planar honeycomb (6,3) networks, in which the organic benzenetricarboxylate anions and the inorganic Co2+ cations play a role of three-connected nodes. Disordered water molecules are intercalated between the layers. A study of
the magnetic properties showed the presence of a weak antiferromagnetic coupling between the Co2+ ions (S = 3/2).
Dedicated to Academician G. A. Abakumov on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1719–1723, September, 2007. 相似文献
60.
The effects of radiofrequency (RF) (1–4) and magnetic fields (5–9) on the behavior of aqueous solutions and suspensions have been a popular subject in recent years. The mechanism of the magnetic “water memory” effect, though, is still largely unknown (5). In this work, we present evidence that the primary “receptor” of the electromagnetic radiation is a gas/liquid interface. Gas can be either already present in water or produced by the effects of electromagnetic fields. Perturbed gas/liquid interfaces require hours to equilibrate. Certain RF and magnetic signals also produce reactive oxygen and hydrogen species (superoxide, hydrogen peroxide, hydrogen, atomic hydrogen). The perturbed gas/liquid interface modifies the hydrogen bonding networks in water and also the hydration of ions and interfaces. Careful outgassing removes all of the effects of the electromagnetic fields, including the magnetic memory effect. The amplitude of the applied field influences the observed effects. Different amplitudes of RF radiation perturb the interfacial water in different ways and consequently affect the behavior of colloids and ions in specific manners. For instance, the bulk and template precipitation of calcium carbonate, zeta potentials of suspended colloids, rate of dissolution of colloidal silica, and attachment of colloidal silica to metal surfaces are modified in specific ways with the low amplitude or high amplitude RF treatments described in this paper. The solubility/diffusivity of gas species is also modified in a different manner, and it is probably at the core of the specificity of the RF amplitude effects. 相似文献