排序方式: 共有16条查询结果,搜索用时 15 毫秒
1.
D. Malferrari Maria Franca Brigatti Angela Laurora L. Medici S. Pini 《Journal of Thermal Analysis and Calorimetry》2006,86(2):365-370
The thermal behavior
of montmorillonite and organically modified montmorillonite, both treated
with heavy metal cations [Cu(II), Cd(II) and Hg(II)], was characterized via
thermal analyses (TG, DTG and DTA) combined with evolved species gas mass
spectrometry (MS-EGA), and X-ray diffraction at in situ controlled temperature
(HTXRD). The reactions involving Cu(II)- and Cd(II)-montmorillonite samples
are mostly related to H2O and OH loss, unlike Hg(II)-montmorillonite,
where effects associated to Hg(II) loss are also present. Finally reactions
related to dehydration, dehydroxylation and to organic matter decomposition
can be observed in montmorillonite samples treated with cysteine. 相似文献
2.
3.
We discuss the notion of spin squeezing considering two mutually exclusive classes of spin-s states, namely, oriented and non-oriented states. Our analysis shows that the oriented states are not squeezed while non-oriented
states exhibit squeezing. We also present a new scheme for construction of spin-s states using 2s spinors oriented along different axes. Taking the case of s=1, we show that the ‘non-oriented’ nature and hence squeezing arise from the intrinsic quantum correlations that exist among
the spinors in the coupled state. 相似文献
4.
The aim of this brief report is to study the behaviour of sheath structure in a multi-component plasma with dust-neutral collisions.
The plasma consists of electrons, ions, micron size negatively charged dust particles and neutrals. The sheath-edge potential
and sheath width are calculated for collisionally dominated sheath. Comparison of collisionless and collisionally dominated
sheath are made. 相似文献
5.
Analysis of a TE011 mode composite sapphire-rutile dielectric resonator has been carried out to study the temperature variation of resonance
frequency, close to the Cs atomic clock hyperfine frequency of 9.192 GHz. The complementary behavior of dielectric permittivity
with temperature of the composite has been exploited to obtain the desired turning point in the resonant frequency. The frequency
of the composite structure is found to be independent of the shield diameter beyond four times the puck diameter. 相似文献
6.
7.
E. Brigatti M. Nú?ez-López M. Oliva 《The European Physical Journal B - Condensed Matter and Complex Systems》2011,81(3):321-326
We perform an analysis of a recent spatial
version of the classical Lotka-Volterra model, where a finite
scale controls individuals’ interaction. We study the
behavior of the predator-prey dynamics in physical spaces higher
than one, showing how spatial patterns can emerge for some values
of the interaction range and of the diffusion parameter. 相似文献
8.
Jin Y.Z. Zhu Y.Q. Brigatti K. Kroto H.W. Walton D.R.M. 《Applied Physics A: Materials Science & Processing》2003,77(1):113-115
Micron-scale coral-like aluminium oxide structures have been generated by heating a mixture of AlB2 and Co powders in a quartz boat at ca. 1050 °C under N2. Upon sonication in acetone, the structures break down into elongated single-crystal aluminium oxide nanorods ranging from
20 to 200 nm in diameter and up to 5 μm in length. Single Co particles are often found attached to nanorod tips. A vapour–liquid–solid
(V–L–S) mechanism appears to be responsible for the aluminium oxide nanorod growth.
Received: 21 January 2003 / Accepted: 22 January 2003 / Published online: 28 March 2003
RID="*"
ID="*"Corresponding author. E-mail: d.walton@sussex.ac.uk 相似文献
9.
Zhu YQ Sekine T Brigatti KS Firth S Tenne R Rosentsveig R Kroto HW Walton DR 《Journal of the American Chemical Society》2003,125(5):1329-1333
The shock-wave resistance of WS(2) nanotubes has been studied and compared to that of carbon nanotubes. Detailed structural features of post-shock samples were investigated using HRTEM, XRD, and Raman spectroscopy. WS(2) nanotubes are capable of withstanding shear stress caused by shock waves of up to 21 GPa, although some nanotube tips and nanoparticles containing multiple structural defects in the bending regions are destroyed. Small WS(2) species, consisting of only a few layers, are extruded from the nanotubes. Well-crystallized tube bodies were found to exhibit significant stability under shock, indicating high tensile strength. XRD and Raman analyses have confirmed this structural stability. Under similar shock conditions, WS(2) tubes are more stable than carbon nanotubes, the latter being transformed into a diamond phase. WS(2) nanotubes containing small concentrations of defects possess significantly higher mechanical strength, and, as a consequence, hollow WS(2) nanoparticles are expected to act as excellent lubricants under much higher loading than was previously thought. 相似文献
10.
Wei Xu Dongliang Chen Wangsheng Chu Ziyu Wu Augusto Marcelli Annibale Mottana Alexander Soldatov Maria Franca Brigatti 《Journal of synchrotron radiation》2011,18(3):418-426
An attempt to refine the local structure of a layered structure such as mica is made by combining angle‐resolved XANES (AXANES) and single‐crystal X‐ray diffraction (SC‐XRD) experiments. Ab initio calculations of AXANES spectra of several tri‐octahedral micas have been used to further interpolate experimental data and to deduce physico/chemical effects. Structural distortions have been found highly correlated with the compositional disordering that arises from electronic interactions between anions and cations, and extend the interlayer entering deep into nearby tetrahedral and octahedral sheets. Multiple occupations at the same atomic site have been investigated in detail both in the parallel and perpendicular components of AXANES spectra. Finally, the best fit obtained, computed in the framework of the multiple‐scattering theory, is presented and the limitations of the muffin‐tin potential in layered systems are briefly discussed. 相似文献