排序方式: 共有25条查询结果,搜索用时 15 毫秒
1.
CV Tomy D Pal SS Banerjee S Ramakrishnan AK Grover S Bhattacharya MJ Higgins G Balakrishnan McK Paul 《Pramana》2002,58(5-6):925-935
The weakly pinned single crystals of the hexagonal 2H-NbSe2 compound have emerged as prototypes for determining and characterizing the phase boundaries of the possible order-disorder
transformations in the vortex matter. We present here a status report based on the ac and dc magnetization measurements of
the peak effect phenomenon in three crystals of 2H-NbSe2, in which the critical current densities vary over two orders of magnitude. We sketch the generic vortex phase diagram of
a weakly pinned superconductor, which also utilizes theoretical proposals. We also establish the connection between the metastability
effects and pinning. 相似文献
2.
Zusammenfassung Mo3CoB3, Mo3NiB3, W3CoB3 und W3NiB3 kristallisieren in einem eigenen Typ (W3CoB3-Struktur). Das trigonal prismatische Bauelement [T
6B]* ist zu Ketten vereinigt, wobei B3-Gruppen entstehen. Die Phasen sind vermutlich Bor-reicher als obiger Formel entspricht.
Mit 2 Abbildungen 相似文献
The crystal structure of W3CoB3 and the isotypic phases Mo3CoB3, Mo3NiB3, and W3NiB3
Mo3CoB3, Mo3NiB3, W3CoB3, and W3NiB3 were found to possess a new type of crystal structure (W3CoB3-structure type). Trigonal prismatic groups [T 6B]* are linked together forming chains in such a way that B3-groups occur. These borides do probably exist with a larger amount of boron as to compared with the formula.
Mit 2 Abbildungen 相似文献
3.
In subnormal glow discharge under d.c. excitation at different pressure in a varying transverse magnetic field (0 to 30 G)
some measurements have been carried out for various initial average tube currents. The voltage across the discharge increases
and average tube current and residual current decreases in the magnetic field. With the help of Beckman’s expression [4] for
the axial field and the electron density distribution in a transverse magnetic field the observed variation of current and
voltage can be satisfactorily explained. The variation of axial electric field with transverse magnetic field can be represented
to a fair degree of accuracy by the derived equation. The behaviour of residual current with magnetic field has been observed
in these oscillations. 相似文献
4.
An integral equation formulation for buoyancy-driven convection problems is developed and illustrated. Buoyancy-driven convection in a bounded cylindrical geometry with a free surface is studied for a range of aspect ratios and Nusselt numbers. The critical Rayleigh number, the nature of the cellular motion, and the heat transfer enhancement are computed using linear theory. Green's functions are used to convert the linear problem into linear Fredholm integral equations. Theorems are proved which establish the properties of the eigenvalues and eigenfunctions of the linear integral operator which appears in these equations. 相似文献
5.
H. Jedlicka H. Nowotny P. Benesovsky 《Monatshefte für Chemie / Chemical Monthly》1968,99(3):1068-1069
Ohne Zusammenfassung 相似文献
6.
Koehler JJ Zhao J Jedlicka SS Porterfield DM Rickus JL 《The journal of physical chemistry. B》2008,112(47):15086-15093
Nitric oxide (NO) is an important cell-signaling molecule whose role in a variety of cellular processes such as differentiation and apoptosis depends strongly on its concentration and flux levels. This work describes and characterizes a novel nitric oxide releasing nanocomposite, capable of photostimulated NO flux that can by dynamically modulated in within a range of biological levels. This material mimics the common compartmentalization strategies used by living cells to achieve its novel features. The material is constructed by encapsulating a photosensitive nitric oxide donor within lipid vesicles with an average diameter of 150 nm. The vesicles are then doped into the interstitial liquid phase of a solid porous silica matrix, which has previously demonstrated biological compatibility and capabilities as a growth surface for mammalian cells. Stimulation by a light source produces a step increase in NO concentration within seconds. The NO flux at the surface of the material is measured to be 14 pmol-cm(-2) sec(-1) using a NO selective self-referencing amperometric microsensor. The NO concentration profile decreases with distance perpendicular to the surface as expected for diffusion from a surface through an aqueous environment. A pattern of one minute light pulses produced uniform pulses of increased NO concentration of one minute duration. A linear relationship exists between NO surface concentration and photon flux, and this relationship can be used to tune the material response. 相似文献
7.
Karl Kirchner Rudolf Jedlicka Roland Schmid 《Monatshefte für Chemie / Chemical Monthly》1992,123(3):203-209
Summary Half-wave potentials,E
1/2, of Fe(ligand)
6
3+/2+
, as ClO
4
–
salt, [ligand=N,N-dimethylformamide (dmf), acetamide (aa), N,N-dimethylacetamide (dma), trimethylphosphate (tmp), dimethylsulfoxide (dmso), and acetonitrile (MeCN) are given. A linear correlation betweenE
1/2 and Gutmann's donor numbers of the ligands, a parameter which expresses quantitatively the Lewis donor properties towards hard acceptors, was found. Ligand replacement on Fe(ligand)
6
3+
in acetonitrile-d
3 was studied by means of1H-NMR spectroscopy at 20°C. An average number of ligands coordinated to Fe3+,n
coord, is given.n
coord increases with the ligand's donor strength; i.e.tmp<dmf<dmso.Dedicated to Prof. Dr. mult. Viktor Gutmann on the occasion of his 70th birthday 相似文献
8.
WANG Er-Kang ZHOU Wei-HongLaboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin SS China 《中国化学》1996,14(2):131-137
Capillary electrpphoresis (CE)/electrochemical detection (EC) for the simultane-ous determination of hydrazine and isoniazid has been developed.The electrochemical method uses a novel modified electrode dispersed with ultrafine platinum particles on the surface of a 30μm carbon fiber microelectrode.The unique characteristic of the Pt-particles modified carbon fiber microelectrode is its excellent stability.The current measurement for hydrazine is more sensitive than that of isoniazid.Selective determination of trace amount of free hydrazine in isoniazid and its formulation can be achieved at applied potential of 0.5V. 相似文献
9.
A Soibel SS Banerjee Y Myasoedov ML Rapparort E Zeldov S Ooi T Tamegai 《Pramana》2002,58(5-6):893-898
Using a novel differential magneto-optical imaging technique we investigate the phenomenon of vortex lattice melting in crystals
of Bi2Sr2CaCu2O8 (BSCCO). The images of melting reveal complex patterns in the formation and evolution of the vortex solid-liquid interface
with varying field (H)/temperature (T). We believe that the complex melting patterns are due to a random distribution of material disorder/inhomogeneities across
the sample, which create fluctuations in the local melting temperature or field value. To study the fluctuations in the local
melting temperature/field, we have constructed maps of the melting landscape T
m(H, r), viz., the melting temperature (T
m) at a given location (r) in the sample at a given field (H). A study of these melting landscapes reveals an unexpected feature: the melting landscape is not fixed, but changes rather
dramatically with varying field and temperature along the melting line. It is concluded that the changes in both the scale
and shape of the landscape result from the competing contributions of different types of quenched disorder which have opposite
effects on the local melting transition. 相似文献
10.
Lorenzo Guazzelli Conor J. Crawford Rebecca Ulc Anthony Bowen Orla McCabe Anne J. Jedlicka Maggie P. Wear Arturo Casadevall Stefan Oscarson 《Chemical science》2020,11(34):9209
A convergent synthetic strategy to Cryptococcus neoformans glucuronoxylomannan (GXM) capsular polysaccharide part structures was developed based on di-, tri-, tetra-, penta- and hexasaccharide thioglycoside building blocks. The approach permitted the synthesis of a library of spacer-containing serotype A and D related GXM oligosaccharide structures, ranging from di- to octadecasaccharides. Ten deprotected GXM compounds (mono- to decasaccharide) were printed onto microarray plates and screened with seventeen mouse monoclonal antibodies (mAbs) to GXM. For the first time a GXM oligosaccharide structure (a serotype A decasaccharide), capable of being recognized by neutralizing forms of these GXM-specific mAbs, has been identified, offering insight into the binding epitopes of a range of protective monoclonal antibodies and furthering our efforts to develop semi-synthetic conjugate vaccine candidates against C. neoformans.A library of Cryptococcus neoformans glucuronoxylomannan (GXM) oligosaccharides was synthesized using a thioglycoside building block strategy. The first GXM microarray was printed, allowing mapping of epitopes of antibodies directed towards GXM. 相似文献