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81.
An experimental program of stylolitic porosity development in stylolitic Atokan (Middle Pennsylvanian) limestones under simulated conditions of deep burial has shown that experimental dissolution preferentially occured and developed along existing styloties. The dissolution sequence was as follows: incipient pores following the traces of stylolites, grading into stylolitic lamellar pores, which enlarged eventually into non-fabric-selective channels. These stylolite-controlled conduits were surrounded by adjacent incipient-to-complete oomolds, enlarged oomolds, incipient-to-complete algal bioclast molds, enlarged biomolds, and halos of intercrystalline porosity to microporosity.
Trace element analysis (Mg, Sr, and Ca) of pore-fluid samples during early phases of experimental deep burial dissolution indicated that slightly less stable protions of carbonates enriched in Mg and Sr dissolved preferentially, as observed also in natural cases. Pyrolysis data indicate that stylolites concerntrated organic matter derived from inter-stylolite areas. This situation demonstrates the pressure-solution origin of stylolites.
Experimental stylolitic pore networks are similar in type, size, and geometry to natural stylolitic porosity. This preferential dissolution suggests that natural stylolites result from late (post pressure-solution dissolution, are not necessarily mechanically induced during stylolite formation as sometimes postulated, and act as effective conduits for secondary porosity generation in deeply-buried carbonate rocks 相似文献
Trace element analysis (Mg, Sr, and Ca) of pore-fluid samples during early phases of experimental deep burial dissolution indicated that slightly less stable protions of carbonates enriched in Mg and Sr dissolved preferentially, as observed also in natural cases. Pyrolysis data indicate that stylolites concerntrated organic matter derived from inter-stylolite areas. This situation demonstrates the pressure-solution origin of stylolites.
Experimental stylolitic pore networks are similar in type, size, and geometry to natural stylolitic porosity. This preferential dissolution suggests that natural stylolites result from late (post pressure-solution dissolution, are not necessarily mechanically induced during stylolite formation as sometimes postulated, and act as effective conduits for secondary porosity generation in deeply-buried carbonate rocks 相似文献
82.
Quasicrystalline low-friction coatings 总被引:7,自引:0,他引:7
83.
Von Glitschka 《计算机光盘软件与应用》2008,(2):102-103
Von Glitschka为我们解释怎样直接用插画技术,来解决创建专业化标识中所遇到的视觉问题。 相似文献
84.
Two techniques for voltage reduction are presented, both of which can significantly reduce the power consumption of digital CMOS circuits. The fixed reduction of voltage is applicable to small systems with a low initial consumption, however, the optimum voltage is not reached and the correct operation of the circuit is not guaranteed. The self-adjusted reduction of voltage is adapted to bigger digital systems. The correct operation of the digital circuit is guaranteed, and the supply voltage is near the optimum for the speed requirements. This technique is more versatile, accurate, and reliable than the fixed one 相似文献
85.
Gábor Csernák Zoltán Pálmai 《The International Journal of Advanced Manufacturing Technology》2009,40(3-4):270-276
We developed a nonlinear mathematical model for chip formation during cutting, comprising four autonomous differential equations and a constitutive equation describing the characteristics of metals. We used a continuation and bifurcation software to find the possible solutions of the differential equations. Certain solutions were determined using numerical simulation and the obtained times series were examined. The seven-dimensional parameter-space of the solutions was partially explored. We found that periodic solutions typically undergo a sequence of period doubling bifurcations as the model parameters are varied. We pointed out during the analysis of the set of equations that chaotic phenomena may also occur besides the formation of continuous chips reflecting a stable equilibrium state and lamellar chips that can be characterised by a periodic solution. Our model was verified by experimental results. 相似文献
86.
87.
J. Miyoshi J.A. Diniz A.D. Barros I. Doi A.A.G. Von Zuben 《Microelectronic Engineering》2010,87(3):267-270
High-k insulators for the next generation (sub-32 nm CMOS (complementary metal-oxide-semiconductor) technology), such as titanium-aluminum oxynitride (TAON) and titanium-aluminum oxide (TAO), have been obtained by Ti/Al e-beam evaporation, with additional electron cyclotron resonance (ECR) plasma oxynitridation and oxidation on Si substrates, respectively. Physical thickness values between 5.7 and 6.3 nm were determined by ellipsometry. These films were used as gate insulators in MOS capacitors fabricated with Al electrodes, and they were used to obtain capacitance-voltage (C-V) measurements. A relative dielectric constant of 3.9 was adopted to extract the equivalent oxide thickness (EOT) of films from C-V curves under strong accumulation condition, resulting in values between 1.5 and 1.1 nm, and effective charge densities of about 1011 cm−2. Because of these results, nMOSFETs with Al gate electrode and TAON gate dielectric were fabricated and characterized by current-voltage (I-V) curves. From these nMOSFETs electrical characteristics, a sub-threshold slope of 80 mV/dec and an EOT of 0.87 nm were obtained. These results indicate that the obtained TAON film is a suitable gate insulator for the next generation (MOS) devices. 相似文献
88.
89.
M.G. Sustersic N.V. AlmeidaA.E. Von Mengershausen S.M. Esquenoni 《International Journal of Hydrogen Energy》2012
The aim of this work is to study the electrochemical oxidation of Hydrogen on gold electrodes in sulphuric acid solution and to compare the results with those obtained in a similar study in perchloric acid solution. In both electrolytes, the reaction is irreversible because the atomic H, which appears as reaction intermediate, diffuses inside of the metal. The reactive is introduced in two ways: by electrolysis at a cathodic potential during different times and by saturating the solution with the gaseous reactive. During the cathodic electrolysis the different crystalline planes of the surface reconstruct and this feature has an influence on the reaction kinetics. The catalytic influence of the incipient hydrous gold oxide on the H electrooxidation is also shown. The presence of sulphate and perchlorate ions leads to unlike voltamperometric profiles in the double layer charging potential region. A gold compound is formed during the metal treatment and an attempt has been done to identify it with FTIR. 相似文献
90.
Zoltán Vitál Nóra Boross István Czeglédi Bálint Preiszner Tibor Erős Kálmán Molnár Gábor Cech Csaba Székely Diána Sándor Péter Takács 《Journal of Great Lakes research》2021,47(1):236-241
In this study, we provide the first genetically verified distribution record beyond its native range of Ligula pavlovskii, a high-impact endoparasite of Ponto-Caspian gobies. According to parasitological surveys, ligulosis was detected for the first time in monkey goby individuals collected from Lake Balaton in 2004, 34 years after the first record of monkey goby in the lake. During a Lake Balaton survey in 2018, we detected tapeworms in 44.4% of the sampled monkey gobies. This prevalence is about two to ten times higher than it was reported from within the native range of the fish hosts. The same survey revealed an uneven spatial distribution of the ligulosis in the monkey gobies inhabiting different shoreline sections of the lake. We assume that the occurrence and recent distribution data of this high-impact endoparasite may provide useful information for potential biocontrol measures of invasive Ponto-Caspian gobies in the future. 相似文献