The dynamics of atmospheric characteristics in the zone of the cyclone which provoked the dangerous atmospheric phenomenon, the heavy snowfall over the center of the European part of Russia in April ...2012, is studied using the data of surface and satellite measurements. Besides the observational data from the meteorological stations, the results are used of the measurement of meteorological variables at the high-altitude meteorological mast in Obninsk and of surface concentration of minor gas components. Revealed is a number of interesting features associated with the passage of the cyclone cloud system over the observational point: the dramatic air temperature drop throughout the 300-m layer of the atmosphere, the formation of intensive vertical motions, and the significant temporal variability of O
3
and NO
2
concentration. The intensity and the total amount of precipitation falling during the cyclone passage are determined using the data of optical measurements of SEVIRI, AVHRR, and MODIS instruments of geostationary and polar orbiting satellites. Demonstrated is the satisfactory agreement of the computed precipitation characteristics with the results of observations at the network of meteorological stations.
Deposition of silica shells onto ZnO nanoparticles (NPs) in dimethyl sulfoxide was found to be an efficient tool for terminating the growth of ZnO NPs during thermal treatment and producing stable ...core–shell ZnO NPs with core sizes of 3.5–5.8 nm. The core–shell ZnO–SiO 2 NPs emit two photoluminescence (PL) bands centred at ∼370 and ∼550 nm originating from the direct radiative electron–hole recombination and defect-mediated electron–hole recombination, respectively. An increase of the ZnO NP size from 3.5 to 5.8 nm is accompanied by a decrease of the intensity of the defect PL band and growth of its radiative life-time from 0.78 to 1.49 μs. FTIR spectroscopy reveals no size dependence of the FTIR-active spectral features of ZnO–SiO 2 NPs in the ZnO core size range of 3.5–5.8 nm, while in the Raman spectra a shift of the LO frequency from 577 cm −1 for the 3.5 nm ZnO core to 573 cm −1 for the 5.8 nm core is observed, which can indicate a larger compressive stress in smaller ZnO cores induced by the SiO 2 shell. Simultaneous hydrolysis of zinc( ii ) acetate and tetraethyl orthosilicate also results in the formation of ZnO–SiO 2 NPs with the ZnO core size varying from 3.1 to 3.8 nm. However, unlike the case of the SiO 2 shell deposition onto the pre-formed ZnO NPs, individual core–shell NPs are not formed but loosely aggregated constellations of ZnO–SiO 2 NPs with a size of 20–30 nm are. The variation of the synthetic procedures in the latter method proposed here allows the size of both the ZnO core and SiO 2 host particles to be tuned.
The purpose of the study is to identify the relationship between drought resistance indicators and the yield of potato plants under unfavorable conditions. A xeromorphic leaf structure is considered ...a diagnostic sign of plant drought resistance. The objects of the study were 24 potato varieties. Planting of seed, pre-planting tillage, harvesting and crop recording were carried out in the period 2020-2022 on the territory of the Samara Research Institute of Agriculture - a branch of the Samara Scientific Center of the Russian Academy of Sciences. Growing conditions for 2021 and 2022 characterized by elevated temperatures and insufficient moisture. The number and size of stomata per unit leaf area were chosen as the criterion for xeromorphism. The studied varieties were divided into two groups (n=12 each) according to the number of stomata. In the first group, the average number of stomata was 26 thousand pcs./cm2 of leaf, and in the second group - 35 thousand pcs. (F=41, p=0.03). More developed structural features of xeromorphism and the accumulation of certain types of metabolites in the second group of varieties led to a 1.6 times greater yield than in the first less xeromorphic group (F=9, p=0.004). The second group was characterized by a large number of mesophyll cells per unit leaf area (584 thousand pieces/cm2 versus 557 thousand pieces), a high content of phospholipids (36 mg/g dry weight versus 31 mg/g), dry weight (0.19 vs. 0.17 g/g wet weight) and the ratio of membrane lipids to membrane proteins (1.4 vs. 1.2). In the less xeromorphic group of plants, the level of oxidative stress, assessed by LPO products, was 0.050 µM/g fresh weight and was 12 % higher than in the more xeromorphic group (F=6, p=0.08). The revealed positive correlation between yield and xeromorphic genotypes indicates the prospects of using this criterion in potato breeding or creating a variety model.
Deposition of silica shells onto ZnO nanoparticles (NPs) in dimethyl sulfoxide was found to be an efficient tool for terminating the growth of ZnO NPs during thermal treatment and producing stable ...core-shell ZnO NPs with core sizes of 3.5-5.8 nm. The core-shell ZnO-SiO
2
NPs emit two photoluminescence (PL) bands centred at ∼370 and ∼550 nm originating from the direct radiative electron-hole recombination and defect-mediated electron-hole recombination, respectively. An increase of the ZnO NP size from 3.5 to 5.8 nm is accompanied by a decrease of the intensity of the defect PL band and growth of its radiative life-time from 0.78 to 1.49 μs. FTIR spectroscopy reveals no size dependence of the FTIR-active spectral features of ZnO-SiO
2
NPs in the ZnO core size range of 3.5-5.8 nm, while in the Raman spectra a shift of the LO frequency from 577 cm
−1
for the 3.5 nm ZnO core to 573 cm
−1
for the 5.8 nm core is observed, which can indicate a larger compressive stress in smaller ZnO cores induced by the SiO
2
shell. Simultaneous hydrolysis of zinc(
ii
) acetate and tetraethyl orthosilicate also results in the formation of ZnO-SiO
2
NPs with the ZnO core size varying from 3.1 to 3.8 nm. However, unlike the case of the SiO
2
shell deposition onto the pre-formed ZnO NPs, individual core-shell NPs are not formed but loosely aggregated constellations of ZnO-SiO
2
NPs with a size of 20-30 nm are. The variation of the synthetic procedures in the latter method proposed here allows the size of both the ZnO core and SiO
2
host particles to be tuned.
Deposition of a SiO
2
shell on luminescent ZnO nanoparticles in dimethylsulfoxide precisely tunes the nanoparticle size from 3 to 6 nm.
Deposition of silica shells onto ZnO nanoparticles (NPs) in dimethyl sulfoxide was found to be an efficient tool for terminating the growth of ZnO NPs during thermal treatment and producing stable ...core-shell ZnO NPs with core sizes of 3.5-5.8 nm. The core-shell ZnO-SiO sub(2) NPs emit two photoluminescence (PL) bands centred at similar to 370 and similar to 550 nm originating from the direct radiative electron-hole recombination and defect-mediated electron-hole recombination, respectively. An increase of the ZnO NP size from 3.5 to 5.8 nm is accompanied by a decrease of the intensity of the defect PL band and growth of its radiative life-time from 0.78 to 1.49 mu s. FTIR spectroscopy reveals no size dependence of the FTIR-active spectral features of ZnO-SiO sub(2) NPs in the ZnO core size range of 3.5-5.8 nm, while in the Raman spectra a shift of the LO frequency from 577 cm super(-1) for the 3.5 nm ZnO core to 573 cm super(-1) for the 5.8 nm core is observed, which can indicate a larger compressive stress in smaller ZnO cores induced by the SiO sub(2) shell. Simultaneous hydrolysis of zinc(ii) acetate and tetraethyl orthosilicate also results in the formation of ZnO-SiO sub(2) NPs with the ZnO core size varying from 3.1 to 3.8 nm. However, unlike the case of the SiO sub(2) shell deposition onto the pre-formed ZnO NPs, individual core-shell NPs are not formed but loosely aggregated constellations of ZnO-SiO sub(2) NPs with a size of 20-30 nm are. The variation of the synthetic procedures in the latter method proposed here allows the size of both the ZnO core and SiO sub(2) host particles to be tuned.
The surface-enhanced infrared spectroscopy was used for analysis of steroid hormone cortisol in biological samples. The concentration dependence of the intensity of the IR absorption modes of ...cortisol deposited on the metal nanoantenna arrays was investigated and the minimum detectable concentration of steroid hormone was determined.
The method of nanostructuring metal surfaces by means of nanolithography was optimized and Au nanoantenna arrays with the controllable parameters on the Si surfaces were formed. The surface-enhanced ...infrared spectroscopy was used for analysis of steroid hormone cortisol in blood plasma.
Surgical treatment of stenosis of the left main coronary artery (LMCA) is a special problem, a number of questions of surgical strategy for this lesion still remain unsolved. The question of direct ...plasty dilatation of LMCA has not lost its actuality. Operations were made on 6 patients in whom direct plasty dilatation of LMCA with a flap from autopericardium was performed for local, not lengthy constriction which was located in the initial and middle part of LMCA. The operations were made under conditions of extracorporeal circulation, moderate general hypothermia (about 32 degrees C), pharmacohypothermic cardioplagia with external cooling of the heart. In all cases there was good restoration of cardiac activity and the absence of myocardium ischemia at the postoperative period. The restoration of the anatomical lumen of LMCA by this method facilitated sufficient blood flow along LMCA. Five years later all the patients are alive, one patient has external angina of the 11 functional class.
The article gives detailed description of a technique of pulmonary endarterectomy in chronic thromboembolic pulmonary hypertension. The method is based on the experience of the world leader in ...surgical treatment of this disease--the clinic of California, San Diego headed by Stuart Jamieson, cardiothoracal clinic Papworth Hospital in the only center in Great Britain, where PE is performed and on the experience obtained by the collective of the Department of hospital surgery of the medical department of the St. Petersburg state University and the City multi-field hospital.
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