This paper presents the results of X-ray diffraction studies on a single crystal of lead zirconate titanate PbZr
0.993
Ti
0.007
O
3
in the region of existence of an intermediate ferroelectric phase. ...In addition to the known superstructure reflections of the M type
q
M
=
and the first-order satellite reflections
q
M
+ {δ, δ, δ}, unknown second-order satellites have been observed near
q
M
and near the Bragg reflections. Structural model of regular system of antiphase domains is used for diffraction calculation. The model is shown to describe the first- and second-orders satellite reflections in the vicinity of
q
M
, but it cannot explain the appearance of satellites around the main Bragg peaks. A possible origin of the system of the superstructures observed in the intermediate phase is discussed.
The Way2Drug informational-computational platform (www.way2drug.com/dr) provides access to the data on drugs approved for medicinal use in the USA and Russian Federation, as well as computational ...possibilities for the prediction of biological activity of drug-like organic compounds. Currently realized computational tools of the platform, which allow one to predict several thousands of biological activity types, including the interaction with molecular targets, pharmacotherapeutic and side effects, metabolism, acute toxicity for rats, cytotoxicity, influence on gene expression, and other properties characterizing the evaluation how promising are particular drug-like compounds as potential pharmaceuticals, are reviewed. Using the Way2Drug platform, one can not only select the most promising "hits" for the synthesis and testing of biological activity but also reveal new indications for the launched drugs.
The coronavirus disease (COVID-19) pandemic has brought into sharp relief the threat posed by coronaviruses and laid the foundation for a fundamental analysis of this viral family, as well as a ...search for effective anti-COVID drugs. Work is underway to update existent vaccines against COVID-19, and screening for low-molecular-weight anti-COVID drug candidates for outpatient medicine continues. The opportunities and ways to accelerate the development of antiviral drugs against other pathogens are being discussed in the context of preparing for the next pandemic. In 2012-2015, Tsyshkova et al. synthesized a group of water-soluble low-molecular-weight compounds exhibiting an antiviral activity, whose chemical structure was similar to that of arbidol. Among those, there were a number of water-soluble compounds based on 5-methoxyindole-3-carboxylic acid aminoalkyl esters. Only one member of this rather extensive group of compounds, dihydrochloride of 6-bromo-5-methoxy-1-methyl-2-(1-piperidinomethyl)-3-(2-diethylaminoethoxy) carbonylindole, exhibited a reliable antiviral effect against SARS-CoV-2
. At a concentration of 52.0 μM, this compound completely inhibited the replication of the SARS-CoV-2 virus with an infectious activity of 106 TCID50/mL. The concentration curves of the analyzed compound indicate the specificity of its action. Interferon-inducing activity, as well as suppression of syncytium formation induced by the spike protein (S-glycoprotein) of SARS-CoV-2 by 89%, were also revealed. In view of its synthetic accessibility - high activity (IC
= 1.06 μg/mL) and high selectivity index (SI = 78.6) - this compound appears to meets the requirements for the development of antiviral drugs for COVID-19 prevention and treatment.
Nanoscale copper (I) oxide layers are formed by magnetron-assisted sputtering onto glassy and silicon substrates in an oxygen-free environment at room temperature, and the structural and optical ...properties of the layers are studied. It is shown that copper oxide formed on a silicon substrate exhibits a lower degree of disorder than that formed on a glassy substrate, which is supported by the observation of a higher intensity and a smaller half-width of reflections in the diffraction pattern. The highest intensity of reflections in the diffraction pattern is observed for Cu
2
O films grown on silicon at a magnetron power of 150 W. The absorption and transmittance spectra of these Cu
2
O films are in agreement with the well-known spectra of bulk crystals. In the Raman spectra of the films, phonons inherent in the crystal lattice of cubic Cu
2
O crystals are identified.
Detailed study of the X-ray diffuse scattering in the paraelectric phase of the PbZr
0.985
Ti
0.015
O
3
was carried out. We concentrated on the analysis of the scattering peculiarities in the ...vicinities of M- and R- points of the Brillouin zone. We have observed a critical increase of the diffuse scattering at the position Q ≈ (0.47 + h 0.53 + k l) slightly aside of M point on cooling to the intermediate phase. We attribute observed critical scattering to a mixed mode containing both oxygen octahedral tilts and antiparallel cationic displacements. Tentative conclusion is made describing earlier reported complicated set of the satellite peaks around M-point as the result of the soft-mode driven incommensurate phase transition.
Modern drug discovery is based on the analysis of information about disease mechanisms, molecular targets, and pharmacological substances, the action of which helps to normalize pathological ...processes. Existing chemical and biomedical databases have recently been supplemented with many specialized computational resources that provide the means to estimate physicochemical properties, biological activity, toxicity, metabolism, and other characteristics of organic molecules in the early stages of drug development. Easy access to this information via the Internet expands significantly the opportunities for an investigator and, at the same time, poses the problem of selecting the information and computational resources most appropriate to the tasks at hand. This paper provides an overview of biomedical and chemical web resources freely available via the Internet and gives recommendations on their optimal use at various stages in the research and development of safer and more effective medicines.
Inelastic X-ray scattering measurements have been done to study the lattice dynamics in lead zirconate titanate solid solution with 0.7% of PbTiO3. The temperature evolution of central peak and ...low-energy transverse phonon branches has been traced. Temperature dependent in-plane transverse polarized acoustic phonon branch in <1 1 0> direction has been revealed. The central peaks of two types have been found. The central peak at small wave vectors can be attributed to the relaxational-type soft ferroelectric mode, while the latter at Q = (1.5 -0.5 0) could be linked to the formation of M-superstructure in the intermediate ferroelectric phase.
The STAR Barrel Electromagnetic Calorimeter Beddo, M.; Bielick, E.; Fornek, T. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2003, Letnik:
499, Številka:
2
Journal Article
Recenzirano
Details concerning the design, fabrication and performance of the STAR Barrel Electromagnetic Calorimeter are presented.
Surface deformation relief (SDR) of the contact areas of a hip joint endoprosthesis subjected to wear was studied at different structural levels using laser scanning microscopy. Quantitative ...comparative 3D analysis of the SDR parameters characterizing postimplantation changes in components of the implant was performed. It was found that wear of the kinematic unit was eccentric and heterogeneous. Deep local surface changes were mainly observed at the upper pole of the head and the insert. The bottom segments of the insert remained intact even after long-term use of the tribological pair. The SDR of these segments remained intact.
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