675 research outputs found
Electroless deposition and Electroplating of Metals
The present paper summarizes the main results of the research on the electroless and electrochemical metal deposition from aqueous solutions, which has been carried out in the Research Institute of Physical-Chemical problems of the Belarussian State University and at the Department of Inorganic Chemistry of the BSU for the last three decades. The paper covers the following problems: the main peculiarities of electroless and electrochemical deposition of copper, nickel, Ni-B,Ni-P, gold films 0.1-30 mkm and more in thickness, their phase composition, morphology and properties; the characteristic features of of hydrometallurgic allowing
(e.g. electroless and electrochemical deposition of a number of binary alloy coatings such as Cu-Ni, Cu-Cd, Cu-Sn, Cu-Zn, Ni-Sn, Ni-W, Ni-Mo), methods of their chemical and phase composition and microstructure regulation, together with correlation between these parameters and alloy properties; the methods for composite metal and alloy film plating from solutions with production of materials including metal oxides and thus possessing unusual and useful properties; the peculiarities of metal film plating onto dielectrics with production of continuous films and metal conductive patterns without the use of photoresists
Dynamics of photogenerated charge carriers in TiO2 /MoO3, TiO2 /WO3 and TiO2 /V2O5 photocatalysts with mosaic structure
Titania is a widely used photocatalytic material possessing such advantages as low cost and high reactivity under the ultraviolet light illumination. However, the fast recombination of photoexcited charge carriers limits its application. Herein, we have synthesized original nanomaterials with mosaic structures that exhibited well-defined heterojunctions and new properties. Using SEM, XRD, EPR spectroscopy, photocatalytic measurements, and photoinduced pathphysiological activity of these photocatalysts, we studied the processes of charge carrier accumulation in TiO2 /MoO3, TiO2 /WO3, and TiO2 /V2 O5 under in situ UV illumination with emphasis on the charge exchange between energy levels of these nanosized semiconductors. It is shown that the accumulation of photoinduced charges occurs in two forms (i) filled electron traps corresponding to Ti4+ /Ti3+ levels and (ii) Mo5+ centers, both forms contributing to the photoinduced biocide activity of the samples. This work demonstrates that light exposure of heterostructure photocatalysts with mosaic surfaces produces different types of charge-trapping centers capable of interacting with molecular oxygen yielding peroxo species, which provide long-life light-induced ”self-cleaning” behavior. Such photoaccumulating materials open new opportunities in developing light-driven self-sterilization structures exhibiting a prolonged bactericidal effect up to 10 h after stopping light exposure. © 2020 by the authors. Licensee MDPI, Basel, Switzerland
Bases for qudits from a nonstandard approach to SU(2)
Bases of finite-dimensional Hilbert spaces (in dimension d) of relevance for
quantum information and quantum computation are constructed from angular
momentum theory and su(2) Lie algebraic methods. We report on a formula for
deriving in one step the (1+p)p qupits (i.e., qudits with d = p a prime
integer) of a complete set of 1+p mutually unbiased bases in C^p. Repeated
application of the formula can be used for generating mutually unbiased bases
in C^d with d = p^e (e > or = 2) a power of a prime integer. A connection
between mutually unbiased bases and the unitary group SU(d) is briefly
discussed in the case d = p^e.Comment: From a talk presented at the 13th International Conference on
Symmetry Methods in Physics (Dubna, Russia, 6-9 July 2009) organized in
memory of Prof. Yurii Fedorovich Smirnov by the Bogoliubov Laboratory of
Theoretical Physics of the JINR and the ICAS at Yerevan State University
In-vivo Studies of Ultrasound-activated Drug-loaded Porous Silicon Nanoparticles for Cancer Therapy Application
It is investigated the therapeutic efficacy of combined action of ultrasound and porous silicon nanoparticles loaded with anticancer drug doxorubicin by using an experimental cancer model of lung Lewis carcinoma in vivo. Time dependences of growth of the primary tumor with introduced nanoparticles and without them, as well as the life span of mice after exposure to therapeutic ultrasound with intensity of 1W/cm2 and frequency of 1 MHz were studied. The obtained results show the effectiveness of inhibiting the growth of primary tumor site, as well as slowing the process of metastasis, in the case of combined action of ultrasound and drug-loaded porous silicon nanoparticles that indicates the prospect of latter as sonosensitizers and nanocontainers for the delivery and controlled release of drugs in sonodynamic therapy of malignant tumors.
Keywords: silicon nanoparticles, nanocontainers, medical ultrasound, sonodynamic therapy, sonosensitizer
Nootropic and anticonvulsant properties of the dry extract from Serratula Centauroides roots
The studies were carried out on white Wistar rats. The dry extract from Serratula centauroides L. was introduced to the animals at the doses of 50,100, and 150 mg/kg for 7 days prior to the testing. The nootropic effect of S. centauroides was estimated by using the test "conditioned passive avoidance reflex". In the groups of animals treated with the S. centauroides extract the number of animals with retained reflex was more than in the control group and the latent period of input into the dark bay of the device was longer than in the animals of the control group. The anticonvulsive activity of the S. centauroides extract was tested on the model of thiosemicarbazide-induced convulsions (30 mg/kg). It has been shown that the S. centauroides extract at the doses of 50-150 mg/kg prolongs the latent period of convulsion onset by 33% and increases the lifespan of the animals by 31-47% on the background of thiosemicarbazide-induced convulsions
Revisiting the 'LSND anomaly' II: critique of the data analysis
This paper, together with a preceding paper, questions the so-called 'LSND
anomaly': a 3.8 sigma excess of antielectronneutrino interactions over standard
backgrounds, observed by the LSND Collaboration in a beam dump experiment with
800 MeV protons. That excess has been interpreted as evidence for the
antimuonneutrino to antielectronneutrino oscillation in the \Deltam2 range from
0.2 eV2 to 2 eV2. Such a \Deltam2 range is incompatible with the widely
accepted model of oscillations between three light neutrino species and would
require the existence of at least one light 'sterile' neutrino. In a preceding
paper, it was concluded that the estimates of standard backgrounds must be
significantly increased. In this paper, the LSND Collaboration's estimate of
the number of antielectronneutrino interactions followed by neutron capture,
and of its error, is questioned. The overall conclusion is that the
significance of the 'LSND anomaly' is not larger than 2.3 sigma.Comment: 30 pages, 16 figures, 6 table
Reply to 'Corrections to the HARP-CDP Analysis of the LSND Neutrino Oscillation Backgrounds'
The alleged mistakes in recent papers that reanalyze the backgrounds to the
'LSND anomaly' do not exist. We maintain our conclusion that the significance
of the 'LSND anomaly' is not 3.8 sigma but not larger than 2.3 sigma.Comment: 3 page
Why the paper CERN-PH-EP-2009-015 (arXiv:0903.4762) is scientifically unacceptable
The paper CERN-PH-EP-2009-015 (arXiv:0903.4762) by A. Bagulya et al. violates
standards of quality of work and scientific ethics on several counts. The paper
contains assertions that contradict established detector physics. The paper
falls short of proving the correctness of the authors' concepts and results.
The paper ignores or quotes misleadingly pertinent published work. The paper
ignores the fact that the authors' concepts and results have already been shown
wrong in the published literature. The authors seem unaware that cross-section
results from the 'HARP Collaboration' that are based on the paper's concepts
and algorithms are in gross disagreement with the results of a second analysis
of the same data, and with the results of other experiments.Comment: 8 pages, 3 figure
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