The effect of the angle of approach of a high-frequency turbulent flow to the waterside on soil erosion in streams was studied experimentally. It was found that both the shear stress and the striking ...force of the flow cause soil erosion under the oblique attack of the flow on the channel wall. The wave mechanisms of erosion were revealed and studied. The derived equations of bank erosion and degradation based on the energy approach to the description of these phenomena showed good agreement between the measured and calculated rates of bank degradation for shallow streams on slopes.
This work reports on various approaches to illuminated I-V curve measurements in monolithic dual and triple-junction GaInP/GaAs/Ge cells with the aim of revealing the action of interconnecting tunnel ...diodes. The measurements were performed both for model samples using a combination of individual sub-cells, connected through an external tunnel diode and for practical concentrator cells with different peak current densities (J p ) of the tunnel diodes in a monolithic structure. Changing of load resistance, or changing of applied voltage from an external source, characterized by variable resistance, was used to obtain I-V curves under both continuous and flash illumination. Also, variation of cell internal resistance due to the current mismatch in sub-cells, caused by illumination spectrum variation, was proven by these measurements
The results of a 7-yr optical and UV spectroscopic study of the high-mass X-ray binary A 0535+26 are presented. It was found that throughout the period of the observations the line profile of Hα ...showed considerable variability. A correlation between the equivalent width of Hα and both V-band magnitude and (B−V) colour excess was observed, albeit with considerable scatter present in the data set. A giant X-ray flare in early 1994 was accompanied by a fading in optical and infrared photometric bands, and a reduction in the equivalent width of Hα. When the star was observed in 1994 September, it was found to have developed a double-peaked Hα profile, and further observations saw the V/R peak ratio vary cyclically, with a period of ~1 yr. If this is identified as a global one-armed oscillation, it becomes the shortest period ever observed in a Be star. The accompanying photometric and spectroscopic observations provide a test of any theory seeking to describe the onset and behaviour of such a density wave.
Copper(II) and cobalt(II) complexes with 4-(3,5-dimethyl-1
H
-pyrazol-1-yl)-6-methyl-2-phenylpyrimidine (L) of the general formula MLX
2
(M = Cu(II), X = Cl and Br; M = Co(II), X = Cl, Br, and I) ...were obtained. According to X-ray diffraction data, CuLBr
2
and CoLX
2
(X = Cl, Br, and I) are mononuclear molecular complexes. The ligand L is coordinated to the metal atom in a chelating bidentate fashion through the N atoms of the pyrimidine and pyrazole rings. The coordination polyhedron of the metal atom is extended to a distorted tetrahedron by two halide ions. In solution, CuLBr
2
undergoes slow transformation into CuL
(1−x)
L′
x
Br
2
and the binuclear (X-ray diffraction data) Cu(I) complex CuL
(1−x
)L′
x
Br
2
(L′ is 4-(4-bromo-3,5-dimethyl-1
H
-pyrazol-1-yl)-6-methyl-2-phenylpyrimidine). The complexes MLX
2
show weak antiferromagnetic interactions between the M
2+
ions.
This paper contains suggestions for experiments with usage of the Spin Physics Detector (SPD) at the first stage of the SPD NICA Programme developing at JINR. Double polarized pp-, dd- and pd- ...collisions at c.m.s. NN energies of 3.4-10 GeV, which will be accessible at the initial stage of experiments, allow one to study spin dependence of the NN interaction, search for multiquark states at double strangeness, charm and beauty thresholds, study the short-range structure of the deuteron. Double polarized pd scattering offer a possibility to test the Standard Model through the search for T-invariance violation.
Complexes Ln(Phen)(C
6
F
5
COO)
3
(Ln = Tb, Eu; Phen = 1,10-phenanthroline) (
I
,
II
) are synthesized. At 300 K these complexes and compounds Ln(C
6
F
5
COO)
3
·
n
H
2
O (Ln = Tb,
n
= 2; Ln = Eu,
n
...= 1) (
III
,
VI
) possess photoluminescence (bright in the case of
I
and
II
). In the spectrum of compound
I
the line at 545 nm (transition
5
D
4
→
7
F
5
) is most intense, whereas in the spectrum of compound
II
the most intense is the line at 613 nm (transition
5
D
0
→
7
F
2
). The replacement of Phen by water decreases the luminescence intensity. The compound Tb
2
(H
2
O)
8
(C
6
F
5
COO)
6
· 2C
6
F
5
COOH (
IV
) is synthesized. According to the X-ray diffraction data, in structure
IV
the molecules of the binuclear Tb(III) complex with the C
6
F
5
COOH molecules form a supramolecular ensemble due to hydrogen bonding. The C
6
F
5
COO
−
ligands perform the monodentate and bidentate bridging function, resulting in the opening of the eight-membered cycle Tb
2
C
2
O
4
. The TbO
8
polyhedron is a distored tetragonal antiprism. The crystals of the binuclear complex Tb
2
(H
2
O)
8
(C
6
F
5
COO)
6
(
V
) are obtained in which the C
6
F
5
COO
−
ligands are monodentate and tridentate bridging cyclic, which results in the closure of two four-membered cycles TbO
2
C and one four-membered cycle Tb
2
O
2
. The TbO
9
polyhedron is a distorted monocapped tetragonal antiprism.
Rearrangements within plasmid DNA are commonly observed during transformation of eukaryotic cells. One possible cause of rearrangements may be recombination between repeated sequences induced by some ...lesions in the plasmid. We have examined the mechanisms of transformation-associated recombination in the yeast Saccharomyces cerevisiae using a plasmid system which allowed the effects of physical state and/or extent of homology on recombination to be studied. The plasmids contain homologous or diverged (19%) repeats of the URA3 genes (from S. cerevisiae or S. carlsbergensis) separated by the genetically detectable ADE2 colour marker. Recombination during transformation for covalently closed circular plasmids was over 100-fold more frequent than during mitotic growth. The frequency of recombination is partly dependent on the method of transformation in that procedures involving lithium acetate or spheroplasting yield higher frequencies than electroporation. When present in the repeats, unique single-strand breaks that are ligatable, as well as double-strand breaks, lead to high levels of recombination between diverged and identical repeats. The transformation-associated recombination between repeat DNAs is under the influence of the RAD52 and RAD1 genes.
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