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421.
Kamran Divaani-Aazar 《Proceedings Mathematical Sciences》2009,119(1):23-35
Let R be a (not necessarily local) Noetherian ring and M a finitely generated R-module of finite dimension d. Let be an ideal of R and denote the intersection of all prime ideals . It is shown that
where for an Artinian R-module A we put
A. As a consequence, it is proved that for all ideals of R, there are only finitely many non-isomorphic top local cohomology modules having the same support. In addition, we establish an analogue of the Lichtenbaum-Hartshorne vanishing theorem over rings
that need not be local. 相似文献
422.
Saeideh Ebrahimiasl Wan Md. Zin Wan Yunus Zulkarnain Zainal Anuar Kassim 《Optical and Quantum Electronics》2012,43(11-15):129-136
Hybrid photovoltaic structures based on transparent conductive SnO2 and electrically conductive polypyrrole (PPy) were prepared. Nanocrystalline SnO2 is considered an n-type barrier and window layer on p-type PPy layer in cell structures. The surface morphology and thickness of the layers were studied using scanning electron microscopy. The optical absorbance data showed an increase of absorbance in contrast with PPy and SnO2. There was a red shift in absorbance wavelengths and a decrease in band gaps for the prepared PV structures. To investigate the electrical properties of the obtained structures, current-voltage characteristic was measured. The best structure showed an open-circuit voltage of 0.170?V, a short-circuit current density of 0.017?mA/cm2, a fill factor of 0.36 and power conversion efficiency of 0.076. 相似文献
423.
In a globalised world where risks spread through contagion, the decision of an entity to invest in securing its premises from stochastic risks no longer depends solely on its own actions but also on the actions of other interacting entities in the system. This phenomenon is commonly seen in many domains including airline, logistics and computer security and is referred to as Interdependent Security (IDS). An IDS game models this decision problem from a game-theoretic perspective and deals with the behavioural dynamics of risk-reduction investments in such settings. This paper enhances this model and investigates the spatio-temporal aspects of the IDS games. The spatio-temporal dynamics are studied using simple replicator dynamics on a variety of network structures and for various security cost tradeoffs that lead to different Nash equilibria in an IDS game. The simulation results show that the neighbourhood configuration has a greater effect on the IDS game dynamics than network structure. An in-depth empirical analysis of game dynamics is carried out on regular graphs, which leads to the articulation of necessary and sufficient conditions for dominance in IDS games under spatial constraints. 相似文献
424.
The growth of Cu3(BTC)2 (BTC = 1,3,5-benzenetricarboxylate), also known as CuBTC and HKUST-1, Metal-Organic Framework (MOF) nanostructures on silk fibers were achieved by layer-by-layer technique in alternating bath of Cu(OAc)2·2H2O and H3BTC solutions under ultrasound irradiation. The effect of pH, reaction time, ultrasound irradiation and sequential dipping steps in growth of the CuBTC Metal-Organic Framework nanostructures has been studied. These systems depicted a decrease in the size accompanying a decrease in the sequential dipping steps. In addition, dense coating of silk fibers with CuBTC MOF results in decrease the emission intensity of silk fibers. The silk fibers containing CuBTC Metal-Organic Framework exhibited high antibacterial activity against Escherichia coli and Staphylococcus aureus. The samples were characterized with powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) spectra and scanning electron microscopy (SEM). XRD analyses indicated that the prepared CuBTC MOF nanostructures on silk fibers were crystalline. 相似文献
425.
Antibacterial fibers have great potential in numerous applications, including bandages, surgical robes, and surgical sutures, and play a significant role in our everyday lives. Here, zeolitic imidazolate framework-67 was synthesized using a green method on silk fibers through a layer-by-layer process under ultrasonic irradiation (ZIF-67@silk [U]) and without ultrasonic irradiation (ZIF-67@silk [B]). Then, iodine was loaded on ZIF-67@silk samples and were assessed as antibacterial fibers with iodine release. Four samples of ZIF-67@silk and I2@ZIF-67@silk were characterized by FT-IR, PXRD, FE-SEM, TGA, BET, and UV–Vis spectroscopy. Finally, antibacterial activity of ZIF-67@silk (B and U) and I2@ZIF-67@silk (B and U) on Staphylococcus aureus as Gram-positive bacteria and Escherichia coli as Gram-negative bacteria was investigated. In addition to ZIF-67@silk samples, iodine-loaded samples showed excellent antimicrobial facility. 相似文献
426.
Metal and polymer matrix composite materials are preferred in bulletproof applications due to their high-impact resistance and lightness. Personal/demand-specific designs that have become possible with the developing additive manufacturing technologies have brought a new perspective to armor technologies. At the same time, parts with complex structures designed with biomimetic approaches can be easily manufactured with additive manufacturing. In this study, biomimetic armors obtained from standard Carbon fiber reinforced polymer (CFRP) and Inconel 718 materials were compared with traditional armor structures. Within the scope of the study, 9 × 19 mm2 parabellum and 7.62 mm NATO bullets were impacted at 275 m/s and 600 m/s speeds on biomimetic and conventional armor consisting of three and five layers. Bullet velocities during impact, deformation of bullets, deformation of armor, and harmonic behavior are discussed. The results obtained were also used to calculate the damped impact energies. In the study, it was determined that biomimetic plates could absorb 22%–38% more impact energy. It has been determined that CFRP materials can absorb 45% more impact energy compared to Inconel 718. 相似文献