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101.
The reactions of 5‐nitriminotetrazole ( 4 ) with 1‐methyl‐5‐aminotetrazole ( 2 ) as well as 2‐methyl‐5‐aminotetrazole ( 3 ) were investigated. In the first reaction 2 was protonated yielding 1‐methyl‐5‐aminotetrazolium 5‐nitrimino‐1H‐tetrazolate monohydrate ( 7 ). In the latter case no protonation could be observed and a co‐crystallization of 5‐nitraminotetrazole and 2‐methyl‐5‐aminotetrazole was obtained. In this compound a new tautomer of 4 could be found. Both products were determined by low temperature single crystal X‐ray diffraction, IR, Raman and multinuclear (1H, 13C, 15N) NMR spectroscopy, elemental analysis as well as differential scanning calorimetry. In addition the heats of formation were calculated using experimentally obtained heats of combustion. With these and the X‐ray densities several detonation parameter were computed using the EXPLO5 software. In addition the sensitivities towards impact, friction and electrostatic discharge were determined. Further, two crystal structures of the important starting materials in energetic research 5‐nitriminotetrazole monohydrate ( 4 ·H2O) and 1‐methyl‐5‐nitriminotetrazolemonohydrate ( 5 ·H2O) are presented and compared with the water‐free compounds. The heats of formation of 4 , 4 ·H2O, 5 , 5 ·H2O have been calculated by the atomization method using the CBS basis set. Inclusion of crystal water decrease heats of formation about 265 kJ mol?1. Also the influence of crystal water on sensitivities (impact, friction, electrostatic discharge) but also performance is discussed. 相似文献
102.
Marek Orlik 《Journal of Solid State Electrochemistry》2009,13(2):245-261
This review paper presents briefly the main concepts of nonlinear dynamics and their exemplary manifestations in selected
systems, including those important from the point of view of materials science. It is an extended version of the conference
presentation. The conditions of instabilities leading to spontaneous formation of dissipative structures are given. Principles
of nonlinear dynamics are illustrated with several examples from the homogeneous and heterogeneous and physical and chemical
systems: pattern formation in the convective motion of fluids subject to various kinds of driving forces, periodic precipitation
phenomena, oscillations, and pattern formation in the Belousov–Zhabotinski (BZ) reaction and the catalytic oxidation of thiocyanate
ions with hydrogen peroxide, as well as bistability and tristability in the electrochemical reduction of azide complexes of
nickel(II). The application of nonlinear dynamics in materials science is first exemplified by its role in polymerization
reactions. Such processes can either exhibit internal couplings leading to oscillations or can be coupled with the chemical
oscillatory process through, e.g., the covalent bonding of its catalyst to the polymer network. Other selected examples of
the application of nonlinear dynamics in materials science, referring to electrochemical processes, were briefly reviewed.
Nonlinear dynamics appears to be useful for designing new materials, including those at the nanoscale.
相似文献
Marek OrlikEmail: |
104.
用紫外分光光度法,找出介孔碳材料对蛋白质的最佳吸附条件,并测定出该介孔碳材料对溶菌酶的最大吸附量。主要从3方面研究介孔碳材料对蛋白质吸附行为的影响。分别是介孔碳材料对蛋白质吸附行为随接触时间的变化产生的影响,pH值的改变对介孔碳材料吸附蛋白质行为的影响,以及介孔碳材料的量的改变对蛋白质吸附行为随接触时间的变化产生的影响。结果表明,当溶菌酶溶液的初始浓度为210μm ol/L,pH值为11.0,接触时间为96h时介孔碳材料对蛋白质即可达到吸附饱和。该介孔碳材料在最佳条件下对溶菌酶的最大吸附量为27.32μm ol/g,表现出优越的溶菌酶吸附性能。 相似文献
105.
106.
107.
E. Paparazzo J.L. Dormann D. Fiorani 《Journal of Electron Spectroscopy and Related Phenomena》1985,36(1):77-91
X-ray photoemission Spectroscopy (XPS) results are presented which have given a direct insight into the surface composition of Fe-Al2 O3 “granular” thin films consisting of fine iron particles (φ ~ 40–150 Å) dispersed in an insulating alumina matrix. The data are mainly discussed in relation to: (i) the bulk iron content in the sample, (ii) the sample preparation procedure (e.g., by rotation of the sample target) and (iii) the mean iron particle size.At the surface, the iron is in a fully oxidized 3+ state within an alumina-rich partly hydrated region. Depth analysis, achieved by an Ar+ etching procedure, provides evidence of metallic iron and iron aluminate forms. In general, the metallic iron percentage increases with depth and with increasing iron bulk content.Good agreement is found between X-ray photoemission spectroscopy and Mössbauer Spectroscopy data. Fe2+ aluminate forms, which indicate an interaction between the metal particle and the alumina matrix, show increasing percentages with decreasing mean particle sizes.Particular attention is paid to evaluating the accuracy of XPS quantitative results, obtained by use of a first-principles model, and to assessing the importance of the artefacts associated with the Ar+ etching procedure. 相似文献
108.
This work concerns the theory of viscoelastic composites which are modelled as mixtures of two interpenetrating solid continua. First it is given a characterization of the boundary-initial value problem in which the initial conditions are incorporated into the field equations. Then a minimum principle for the dynamic theory is established. 相似文献
109.
Barbara R. Hillery James E. Girard Michele M. Schantz Stephen A. Wise 《Journal of separation science》1995,18(2):89-96
A novel p,p-cyanobiphenyl stationary phase (p-cyanobiphenyl, p-allyloxy methylpolysiloxane) has been evaluated for the GC investigation of polychlorinated biphenyls (PCBs). Several PCB congeners which coelute on the phases typically used for PCB analysis (e.g. 5% phenyl methylpolysiloxane) are separated on the p,p-cyanobiphenyl phase, including the hexachlorobiphenyl congeners PCB 163, PCB 164, and PCB 138. In this work, a p,p-cyanobiphenyl stationary phase was used to measure selected PCB congeners in two Standard Reference Materials (SRMs) available from the National Institute of Standards and Technology (NIST), and two Certified Reference Materials (CRMs) available from the Community Bureau of Reference (BCR). The materials analyzed were SRM 1588, Organics in Cod Liver Oil; SRM 1945, Organics in Whale Blubber; CRM 349, Chlorobiphenyls in Cod Liver Oil; and CRM 350, Chlorobiphenyls in Mackerel Oil. Concentrations are reported for several PCB congeners which coelute on the 5% phenyl methylpolysiloxane, including PCB 163 and PCB 164. 相似文献
110.