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31.
Kariate Sudhakara Prasad A. B. Arun P. D. Rekha Chiu‐Chung Young Jen‐Lin Chang Jyh‐Myng Zen 《Electroanalysis》2009,21(14):1646-1650
Aerobically grown Shewanella sp. bacterial suspension drop‐coated on a disposable screen‐printed carbon electrode was found to possess electroactivity without the aid of redox mediator. Cyclic voltammetric studies revealed the characteristics of a mixed diffusion adsorption‐controlled electrochemical process for direct electron transfer at the bacteria‐modified electrode. Both FE‐SEM and ATR FT‐IR experiments were carried out to investigate the surface characteristics. The electroanalytical applicability was further demonstrated for electrocatalytic reduction of arsenite, hydrogen peroxide and nitrite. Low cost and very simple manufacturing procedure allow for the proposed bacterial sensor to be applied as disposable devices. 相似文献
32.
We apply unrestricted Hartree-Fock to modelling two systems:
- (1)
- We calculate the spin structure and addition spectra of small symmetric quantum dots (often called 2D “artificial atoms”), improving the accuracy considerably by including, for the first time, second-order correlation corrections. We compare the results to experiment and to previous numerical works, and find that our spin structure in some cases disagrees with that calculated within mean-field theories, such as Hartree-Fock without correlation corrections, or density-functional theory [C. Sloggett, O.P. Sushkov, Phys. Rev. B 71 (2005) 235326].
- (2)
- We model the well-known 0.7 anomaly in the conductance of a quantum point contact. We calculate the conductance using direct calculation of scattering phases on a ring, within Hartree-Fock. We observe strong localisation of the Fermi electrons on the barrier, and suggest a mechanism for the observed temperature-dependent conductance anomaly.
33.
Boleslaw Grabowski 《Pramana》1987,29(5):455-460
The impact broadening by charged electron gas is calculated. A proper account of the Debye screening has been taken as also
the curvilinearity of the perturber’s trajectories. The results have been given in the form of graphs for a ready comparison
with earlier results. 相似文献
34.
在欧姆加热和低混杂波电流驱动条件下,利用磺化汞半导体探测器和碘化钠和探测器测出了HL-1M装置的X射线能谱,研究了器壁硅化前后电子速率分布和电子温度变化的特点,给出了X射线辐射强度与LHCD能量沉积的关系。 相似文献
35.
Advances in transmission electron microscopy coupled to increasingly powerful biocomputing techniques are opening enormous possibilities to understand the structure and function of complex biological processes performed by large multi-protein assemblies. This is an exciting time for electron microscopists because we can combine our efforts with X-ray crystallographers and NMR spectroscopists to reach the prospect of studying the structure and dynamics of the so-called ‘molecular machines’. One of these fascinating systems is the macromolecular complex formed around double-stranded DNA breaks (DSBs). Non-homologous end-joining (NHEJ) is the main DSBs repair pathway in mammalian cells, where a collection of proteins interact to rejoin two broken DNA ends. During NHEJ, DNA-dependent protein kinase (DNA-PK) binds damaged DNA with high affinity and acts as the main scaffold for other repair factors. Several studies have made use of the electron microscope to reveal the three-dimensional architecture of DNA-PK and the structural basis for the recognition of damaged DNA and the activation of DNA-PK's kinase activity. 相似文献
36.
《Physics letters. A》2019,383(17):2110-2113
The electron effective mass in GaAs quantum wires has been estimated by using a full dynamical random-phase approximation to examine its properties versus spin polarization, temperature, and carrier density. A decrease of mass with spin polarization is seen. The minority mass increases with the polarization while the majority mass decreases and this behaviour is seen for all densities. A maximal enhancement of mass at moderate temperature around 25 K is also presented. These calculations show a qualitative consistence with results in two-dimensional systems and help to control the electronic transport in quantum wires. 相似文献
37.
Electron induced desorption of hydrogen on polycrystalline platinum has been studied in continuation of former work. The results
remain consistent with a supposed adsorption model implying that electron induced H+ emission is restricted to hydrogen adsorbed only at particular sites occupying not more than 1 per cent coverage. These sites
are ascribed to characteristic and stable surface impurities which are not influenced by the improved target treatment applied.
Depletion of sites by sputter cleaning is cancelled by recovery during annealing. The highest observed H+ yield (all available sites filled with hydrogen) is 2 · 10−5 ions per electron. The total cross section for desorption by electron impact is 2 · 10−17 cm2. Complex interaction phenomena between the electrons and the hydrogen covered platinum surface have been observed. 相似文献
38.
Electron spin resonance studies have been carried out on Cu2+ ion doped in single crystals of cadmium maleate dihydrate at 303 and 77K. It has been found that Cu2+ enters this lattice interstitially. The spin Hamiltonian parameters have been evaluated and the ground state wave function
is found to be predominantly |X
2 −Y
2〉 with a slight admixture of |3Z
2 −r
2〉. 相似文献
39.
Tridib Kumar Bhowmick Akkihebbal K. Suresh Shantaram G. Kane Ajit C. Joshi Jayesh R. Bellare 《Journal of nanoparticle research》2009,11(3):655-664
Herbs and minerals are the integral parts of traditional systems of medicine in many countries. Herbo-Mineral medicinal preparations
called Bhasma are unique to the Ayurvedic and Siddha systems of Indian Traditional Medicine. These preparations have been used since long and are claimed to be the very effective
and potent dosage form. However, there is dearth of scientific analytical studies carried out on these products, and even
the existing ones suffer from incomplete analysis. Jasada Bhasma is a unique preparation of zinc belonging to this class. This particular preparation has been successfully used by traditional
practitioners for the treatment of diabetes and age-related eye diseases. This work presents a first comprehensive physicochemical
characterization of Jasada Bhasma using modern state-of-the-art techniques such as X-ray photoelectron spectroscopy (XPS), inductively coupled plasma (ICP),
elemental analysis with energy dispersive X-ray analysis (EDAX), dynamic light scattering (DLS), and transmission electron
microscopy (TEM). Our analysis shows that the Jasada Bhasma particles are in oxygen deficient state and a clearly identifiable fraction of particles are in the nanometer size range.
These properties like oxygen deficiency and nanosize particles in Jasada Bhasma might impart the therapeutic property of this particular type of medicine.
A. C. Joshi: Private Practitioner (Vaidya). 相似文献
40.
In this Letter the results of theoretical investigations of the chaotic microwave oscillator based on the electron beam with a virtual cathode are presented. Nonlinear non-stationary processes in these electron systems are studied by means of numerical analysis of 2.5D model. It was discovered that the non-uniform external magnetic field value controls the dynamical regime of oscillations in the virtual cathode oscillator. The processes of the chaotization of output microwave radiation are described and interpreted from the point of view of the formation and interaction of electron structures (bunches) in the electron beams. The numerical results have shown that the investigated electron system with virtual cathode could be considered as a promising controlled source of wideband chaotic oscillations in the microwave range. 相似文献