Influence of temperature on critical fields in ZnxSbyCrzSe4

The electrical and complex ac dynamic magnetic susceptibility measurements were used to study an influence of temperature on critical fields in single-crystalline ZnxSbyCrzSe4 spinel system with y = 0:11, 0.16 and 0.20. The p-type conduction and a shift both of the Néel temperature TN to lower temperatures and a susceptibility peak at Tm in the paramagnetic region — to higher temperatures were established. Below TN the magnetic field dependence of susceptibility, Âac(H), shows two peaks. First peak at the critical field Hc1 slightly decreases with temperature and remains almost constant as Sb content increases. Second peak at the critical field Hc2 drops rapidly with temperature and remains almost unchanged as Sb content increases. At TN both critical fields disappear

Specific heat and magnetic properties of single-crystalline (Zn0.925In0.054)[Cr1.84In0.152]Se-4 semiconductor

An antiferromagnetic order with a Néel temperature TN = 17:5 K, a strong ferromagnetic exchange evidenced by a positive Curie Weiss temperature CW = 77:3 K, the fuzzy peaks in the real component of susceptibility x′ (T) and the disappearance of the second critical eld were established. The curvature of speci c heat C(T) and C(T)=T in surrounding of TN indicated a broad peak, characteristic for the system with inhomogeneous magnetic state (spin-glass-like phase). The calculated magnetic entropy showed the value of S(T) 1 J/(mol K) which is extremely small; i.e., much lower than the magnetic contribution Rln(2S + 1) = 11:52 J/(mol K) calculated for the spin 3/2

Subcellular distribution and expression of cofilin and ezrin in human colon adenocarcinoma cell lines with different metastatic potential

The dynamic reorganization of the actin cytoskeleton is regulated by a number of actin binding proteins (ABPs). Four human colon adenocarcinoma cell lines – parental and three selected sublines, which differ in motility and metastatic potential, were used to investigate the expression level and subcellular localization of selected ABPs. Our interest was focused on cofilin and ezrin. These proteins are essential for cell migration and adhesion. The data received for the three more motile adenocarcinoma sublines (EB3, 3LNLN, 5W) were compared with those obtained for the parental LS180 adenocarcinoma cells and fibroblastic NRK cells. Quantitative densitometric analysis and confocal fluorescence microscopy were used to examine the expression levels and subcellular distribution of the selected ABPs. Our data show distinct increase in the level of cofilin in adenocarcinoma cells accompanied by the reduction of inactive phosphorylated form of cofilin. In more motile cells, cofilin was accumulated at cellular periphery in co-localization with actin filaments. Furthemore, we indicated translocation of ezrin towards the cell periphery within more motile cells in comparison with NRK and parental adenocarcinoma cells

Mictomagnetic order in Cd0.87Cr1.93V 0.06Se4 semiconductor

The complex ac dynamic magnetic susceptibility was used to study the mictomagnetic-like behavior in polycrystalline Cd0:87Cr1:93V0:06Se4 spinel. The temperature dependences of the zero field in-phase (real part) and out-of-phase (imaginary part) components of fundamental susceptibility measured at the oscillating field Hac = 0:5 Oe and at the constant frequency of 125 Hz are characteristic for the mictomagnetic order. These results well correlate with the anomalies in the second and third harmonics of the ac susceptibility indicating the cluster glass

Usluge, dostava i prijevoz u okviru ideje o rasterećivanju metalurškog poduzeća

The paper discusses the methodology of outsourcing as a modern method to help the management process through the shaping of the structures of business activity. The use of this concept is associated with a new approach to the function of supplies and transport, as well as service activity conducted in an enterprise. Outsourcing procedures used in the Polish metallurgical industry bring about substantial effects and benefits related to the restructuring process.U radu se raspravlja metodologija rasterećivanja kao moderna metoda koja pomaže u procesu rasterećivanja oblikovanjem ustroja poslovne aktivnosti. Uporaba ovog koncepta povezana je s novim pristupom funkciji dostave i prijevoza, kao i uslužnim aktivnostima koje se provode u nekom poduzeću. Postupci rasterećivanja koji se primjenjuju u poljskoj metalurškoj industriji daju suštinske efekte i prednosti koje se odnose na procese restrukturiranja

Electrical and magnetic studies of the CdxCryV zSe4 Spinels

The electrical and magnetic investigations carried out on the polycrystalline spinels with the general chemical formula CdxCryVzSe4 (where z = 0:06, 0.12, 0.24, and 0.31) revealed semiconducting and ferromagnetic properties with a Curie temperature of 127.5 K. A step-like structure of the electrical conductivity, ¾(T), was observed for the polycrystal containing 6% V ions in the octahedral sites while the remaining samples showed a typical Arrhenius behaviour of ¾(T). These effects are interpreted in terms of ferromagnetic spin clusters which finally dissolve on going towards the paramagnetic limit including non-stoichiometry

Platinum(II) complexes with cyclometallated 5-pi-delocalized-donor-1,3-di(2-pyridyl)benzene ligands as efficient phosphors for NIR-OLEDs

Two new pincer proligands, namely 5-(p-(N,N-diphenylamino)phenylethynyl)-1,3-di(2-pyridyl)benzene (HL1) and trans-5-(p-(N,N-diphenylamino)styryl-1,3-di(2-pyridyl)benzene (HL2) were prepared together with their N^C^N-coordinated cyclometallated platinum(II) complexes PtL1X (X = Cl, NCS) and PtL2Cl. Both ligands are intensely luminescent in solution (quantum yields > 0.8). PtL1X complexes display high quantum yields in solution whereas that of PtL2Cl is very low due to the ease with which trans to cis isomerisation of the diphenylaminostyryl C[double bond, length as m-dash]C bond occurs. Distinct sets of emission bands attributable to the cis and trans forms are observable in glass at 77 K, the assignments being supported by TD-DFT calculations. Organic light-emitting diodes (OLEDs) have been prepared using the new compounds as phosphorescent emitters. Remarkably, despite the inferior quantum yield of PtL2Cl in solution, the best electroluminescence quantum efficiencies are obtained with this complex, which emerges as an excellent candidate for the preparation of NIR-OLEDs

Magnetic coupling in CuCr2X4 (X = S, Se) spinel compounds obtained via substitution of the chromium ions by nonmagnetic Sb or Al ions

Taking into account both the dc magnetic susceptibility and the magnetization measurements as well as the high-temperature expansion of the magnetic susceptibility procedure the hopping integrals and superexchange integrals for the first and second coordination sphere were evaluated. The two hopping integrals are positive and many times greater than the superexchange ones. The obtained results testify to that in the stoichiometric compounds under study the double-exchange magnetic interaction is the main mechanism responsible for very strong, ferromagnetic coupling. Using the total hopping integral B the bandwidth of mixed valence band of chromium ions was determined

High-resolution Fourier-transform spectroscopy and deperturbation analysis of the A¹Π(v = 1) level in ¹²C¹⁸O

The A1Π(v = 1) level of the 12C18O isotopologue was precisely reinvestigated with two complementary spectroscopic techniques. High resolution B1Σ+ → A1Π(0, 1), (1, 1) and C1Σ+ → A1Π(0, 1) emission bands were recorded in the visible region, 20,700 – 26,100 cm−1, with a 1.71 m Fourier-transform spectrometer (Bruker IFS 125-HR) installed at the University of Rzeszów. The resulting line centre accuracy of isolated and medium to strong lines is 0.005 cm−1. In addition, high-resolution spectra of the A1Π ⟵ X1Σ+(1, 0), B1Σ+⟵ X1Σ+(0, 0) and (1, 0) as well as C1Σ+⟵ X1Σ+(0, 0) bands were recorded between 66,200 and 95,250 cm−1 using the vacuum-ultraviolet Fourier-transform spectrometer installed at the DESIRS beamline of the SOLEIL synchrotron. The wavenumber accuracy for isolated and strong spectral lines is 0.01 cm−1. A data set of 626 spectral lines belonging to seven bands was incorporated into a global deperturbation analysis. Significantly improved deperturbed molecular constants for the A1Π(v = 1), a´3Σ+(v = 10), D1Δ(v = 1), and I1Σ−(v = 2) levels, term values of the B1Σ+(v = 0, 1) and C1Σ+(v = 0) Rydberg states as well as the accompanying spin-orbit and rotation-electronic (L-uncoupling) interaction parameters were obtained. The experimental ro-vibrational term values of the A1Π(v = 1) level and its perturbers were also determined. The mixed composition of interacting states is expressed in terms of their 1Π percentage character