scholarly journals CRYSTAL LATTICE ROTATIONS DURING PLASTIC DEFORMATION OF TWO-DIMENSIONAL POLYCRYSTALLINE Al SAMPLES

2020 ◽  
pp. 56-59
Author(s):  
E.E. Badiyan ◽  
Ye.V. Ftomov ◽  
O.V. Shekhovtsov ◽  
A.G. Tonkopryad
Keyword(s):  
Crystal Lattice ◽  
Uniaxial Tension ◽  
Tensile Axis ◽  
Theoretical Studies ◽  
Two Dimensional ◽  
Slip Direction ◽  
Polycrystalline Aluminum ◽  
First Time ◽  
Fcc Structure

Theoretical studies of feasible rotations of the crystal lattice during the deformation of samples with an FCC structure under uniaxial tension are carried out. The results of the experimental determination of the magnitudes of these rotations for various grains of two-dimensional polycrystalline aluminum samples after their deformation by the same strain value are presented. For the first time, it has been theoretically shown and experimentally confirmed that under uniaxial tension of a specimen under the conditions of operation of only one slip system, regardless of the scheme of rotation, the magnitude of the rotation is determined only by the angle between the direction of the tensile axis and the slip direction before deformation of the specimen.

scholarly journals The determination of isoflavones and coumestrol by capillary electrophoresis

2013 ◽  
Vol 19 (No. 4) ◽  
pp. 132-138 ◽  
Author(s):  
J. Moravcová ◽  
T. Kleinová
Keyword(s):  
Capillary Electrophoresis ◽  
Fused Silica ◽  
Biochanin A ◽  
Detector Response ◽  
Two Dimensional ◽  
Nmr Spectrum ◽  
Fused Silica Capillary ◽  
First Time ◽  
Silica Capillary

The separation of six isoflavones (biochanin A, isoformononetin, formononetin, prunetin, daidzein and genistein) and coumestrol on an uncoated fused-silica capillary electrophoresis column was optimised using alkaline borate buffer as electrolyte and DAD detection. A baseline separation of all analytes except a pair, formononetin-biochanin A was achieved at pH 10.5 in 25 min. Detection limits were low (0.1 µg/ml) and the linearity of the detector response was established in the concentration range 0.4–60 µg/ml (180 µg/ml for coumestrol). Coumestrol was synthesized and the carbon signals in 13C-NMR spectrum of both coumestrol and di-O-acetylcoumestrol were assigned for the first time using two-dimensional HMQC technique.

scholarly journals A Ca2+ MOF combining highly efficient sorption and capability for voltammetric determination of heavy metal ions in aqueous media

2019 ◽  
Vol 7 (25) ◽  
pp. 15432-15443 ◽  
Author(s):  
Anastasia D. Pournara ◽  
Antigoni Margariti ◽  
Georgios D. Tarlas ◽  
Andreas Kourtelaris ◽  
Valeri Petkov ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Electrochemical Sensor ◽  
Heavy Metal Ions ◽  
Aqueous Media ◽  
Voltammetric Determination ◽  
Dual Function ◽  
Two Dimensional ◽  
First Time

The two-dimensional Ca-MOF shows a dual function as a sorbent and an electrochemical sensor for heavy metal ions, which is reported for the first time for a MOF material.

Determination of Absolute Signs of 119Sn-117Sn Spin-Spin Coupling Constants

1994 ◽  
Vol 49 (10) ◽  
pp. 1407-1409 ◽  
Author(s):  
Bernd Wrackmeyer ◽  
Gerald Kehr
Keyword(s):  
Long Range ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Two Dimensional ◽  
Spin Coupling Constants ◽  
Spin Spin Coupling ◽  
First Time

AbstractIf for a given system two-dimensional (2D) 119Sn/1H heteronuclear shift correlations can be established for long range coupling constants nJ(119Sn,1H) (n = 4, 6), absolute signs of coupling constants J(Sn,Sn) are accessible by this technique for the first time. This has been demonstrated for tetrakis(trimethylstannyl)allene (1) with 2J(119Sn,117Sn) (>0) and 4J(Sn. 117Sn) (<0) and for tris(trimethylstannyl)phosphane (2) and bis(trimethvlstannyl)- sulfane (3) with 2J(119Sn,117Sn) (<0).

Determination of Coupling Signs 1J(119Sn, 15N ) and 2J(119Sn, 117Sn) in Trimethylstannylamines

1998 ◽  
Vol 53 (12) ◽  
pp. 1494-1500 ◽  
Author(s):  
Bernd Wrackmeyer ◽  
Jürgen Weidinger ◽  
Heinrich Nöth ◽  
Wolfgang Storch ◽  
Thomas Seifert ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
Lone Pair ◽  
Coupling Constants ◽  
Positive Sign ◽  
Two Dimensional ◽  
Ultrahigh Resolution ◽  
Sign Inversion ◽  
First Time ◽  
Influence Of Substituents

The l5N-labelled trimethylstannylamines 1 - 3 [(Me3Sn)3N, (Me3Sn)2NPh, (Me3Sn)2NBCgHi4 (BCgHi4 = 9-borabicyclo[3.3.0]nonyn and the non-labelled 4, Me3Sn-N(BC8Hi4)2 , were prepared and studied by 1H, 1C, 15N and 119Sn NMR. The 15N ultrahigh resolution NMR spectra of 1 revealed otherwise unobserved parameters such as 2J(15N ,Sn ,13C ) and the isotope induced chemical shift 2Δ12/13C(15N). 119Sn NMR spectra of 1, recorded under similar conditions, also show new parameters such as 3J(119Sn,N,Sn,13C) which are not resolved in the non-labelled derivative. By using various types o f two-dimensional heteronuclear shift correlations, absolute coupling signs of 1J(119Sn,15N) (all < 0) in 1 - 3 were determined. By the same techniques it proved possible to confirm the negative sign o f :7(Sn,Sn) (-195.4 Hz) in 1. In contrast, the coupling constants 2J(Sn,Sn) for 2 (+71.7) and 3 (+62.0) possess a positive sign. This sign inversion, observed here for the first time for apparently similar compounds, demonstrates the enormous influence of substituents on the nature of the lone pair of electrons at the nitrogen atom. It also shows that these experiments for sign determinations of coupling constants are necessary in order to interpret these data correctly.

Disability as a social phenomenon

2020 ◽  
pp. 22-38
Author(s):  
Natalia Guseva ◽  
Vitaliy Berdutin
Keyword(s):  
Social Protection ◽  
Russian Society ◽  
Stage Model ◽  
High Quality ◽  
Rehabilitation Programs ◽  
Current State ◽  
The Social ◽  
Consistent Solution ◽  
First Time

At present, the problem of establishing disability is a point at issue in Russia. Despite the fact that medical criteria for disability are being developed very actively, high-quality methods for assessing social hallmarks are still lacking. Since disability is a phenomenon inherent in any society, each state forms a social and economic policy for people with disabilities in accordance with its level of development, priorities and opportunities. We have proposed a three-stage model, which includes a system for the consistent solution of the main tasks aimed at studying the causes and consequences of the problems encountered today in the social protection of citizens with health problems. The article shows why the existing approaches to the determination of disability and rehabilitation programs do not correspond to the current state of Russian society and why a decrease in the rate of persons recognized as disabled for the first time does not indicate an improvement in the health of the population. The authors proposed a number of measures with a view to correcting the situation according to the results of the study.

Phytochemical Constituents of Annona reticulata and their Cytotoxic Activity

2020 ◽  
Vol 17 (3) ◽  
pp. 206-210
Author(s):  
Ty Viet Pham ◽  
Thang Quoc Le ◽  
Anh Tuan Le ◽  
Hung Quoc Vo ◽  
Duc Viet Ho
Keyword(s):  
Cytotoxic Activity ◽  
Cell Lines ◽  
Structural Determination ◽  
Phytochemical Investigation ◽  
Ic50 Values ◽  
Phytochemical Constituents ◽  
First Time ◽  
Annona Reticulata

A phytochemical investigation of the leaves of Annona reticulata led to the isolation and structural determination of β-sitosterol (1), ent-pimara-8(14),15-dien-19-oic acid (2), ent-pimara- 8(14),15-dien-19-ol (3), quercetin (4), quercetin 3-O-α-L-arabinopyranoside (5), and a mixture of quercetin 3-O-β-D-galactopyranoside (6a) and quercetin 3-O-β-D-glucopyranoside (6b). Of these, compounds 2 and 3 were isolated from the genus Annona for the first time. Compound 3 showed strong cytotoxicity against SK-LU-1 and SW626 cell lines with IC50 values of 17.64 ± 1.07 and 19.79 ± 1.41 μg mL-1, respectively.

Sign in / Sign up

Export Citation Format

Share Document