Spin transport and spin dephasing in zinc oxide

The wide bandgap semiconductor ZnO is interesting for spintronic applications because of its small spin-orbit coupling implying a large spin coherence length. Utilizing vertical spin valve devices with ferromagnetic electrodes (TiN/Co/ZnO/Ni/Au), we study the spin-polarized transport across ZnO in all-electrical experiments. The measured magnetoresistance agrees well with the prediction of a two spin channel model with spin-dependent interface resistance. Fitting the data yields spin diffusion lengths of 10.8nm (2K), 10.7nm (10K), and 6.2nm (200K) in ZnO, corresponding to spin lifetimes of 2.6ns (2K), 2.0ns (10K), and 31ps (200K).Comment: 7 pages, 5 figures; supplemental material adde

Microsolvation and sp²-stereoinversion of monomeric α-(2, 6-di-tert-butylphenyl)vinyllithium as measured by NMR

The beta-unsubstituted title compound dissolves in THF as a uniformly trisolvated monomer, whereas it forms exclusively disolvated monomers in tert-butyl methyl ether, Et2O, TMEDA, or toluene with TMEDA (1.4 equiv). This was established at low temperatures through the observation of separated NMR signals for free and lithium-coordinated ligands and/or through the patterns and magnitudes of C-13, Li-6 NMR coupling constants. An aggregated form was observed only with Et2O (2 equiv) in toluene as the solvent. The olefinic geminal interproton coupling constants of the H2C= part can be used as a secondary criterion to differentiate between these differently solvated ground-states (3, 2, or <2 coordinated ligands per Li). Due to a kinetic trisolvation privilege of THF, the cis/trans sp(2)-stereoinversion rates could be measured through analyses of H-1 NMR line broadening and coalescence only in THF as the solvent: The pseudomonomolecular (because THF-catalyzed),ionic mechanism is initialized by a C-Li bond heterolysis with the transient immobilization of one additional THF ligand, followed by stereoinversion of the quasi-sp(2)-hybridized carbanionic center in cooperation with a "conducted tour" migration of Li+(THF)(4) along the alpha-aryl group within the solvent-separated ion pair

Circuit Electromechanics with a Non-Metallized Nanobeam

We have realized a nano-electromechanical hybrid system consisting of a silicon nitride beam dielectrically coupled to a superconducting microwave resonator. We characterize the sample by making use of the Duffing nonlinearity of the strongly driven beam. In particular, we calibrate the amplitude spectrum of the mechanical motion and determine the electromechanical vacuum coupling. A high quality factor of 480,000 at a resonance frequency of 14 MHz is achieved at 0.5 K. The experimentally determined electromechanical vacuum coupling of 11.5 mHz is quantitatively compared with finite element based model calculations.Comment: Typos and one reference have been correcte

An anisotropic pseudo-elastic model for the mullins effect in arterial tissue

This paper is focused on developing the theory which describes the Mullins effect in human arterial tissue. Cyclic uni-axial tensile tests were performed to obtain data characterizing the Mullins effect in arterial tissue. In order to account anisotropy of arterial tissue, longitudinally as well as circumferentially resected samples of human aorta were tested. Each sample underwent repeated (four times) loading and unloading to a certain value of maximum stretch. This limiting stretch increased in several consecutive steps. The arterial wall is considered as hyperelastic, locally orthotropic, incompressible material. A strain energy function is adopted in the limiting fiber extensibility form. Description of primary material response, followed by material stress softening in the repeated cycles, is based on pseudo-elastic constitutive model proposed by Dorfmann and Ogden. This theory is developed using anisotropic form of the softening variable. The primary loading curve and the fourth unloading curve of each set of cycles are chosen for regression analysis. The model with thus estimated parameters successfully fits experimental data and is suitable for application in biomedicin

A universal platform for magnetostriction measurements in thin films

We present a universal nanomechanical sensing platform for the investigation of magnetostriction in thin films. It is based on a doubly-clamped silicon nitride nanobeam resonator covered with a thin magnetostrictive film. Changing the magnetization direction within the film plane by an applied magnetic field generates a magnetostrictive stress and thus changes the resonance frequency of the nanobeam. A measurement of the resulting resonance frequency shift, e.g. by optical interferometry, allows to quantitatively determine the magnetostriction constants of the thin film. We use this method to determine the magnetostriction constants of a 10nm thick polycrystalline cobalt film, showing very good agreement with literature values. The presented technique can be useful in particular for the precise measurement of magnetostriction in a variety of (conducting and insulating) thin films, which can be deposited by e.g. electron beam deposition, thermal evaporation or sputtering

A sertéshústermelés színvonala és jövedelmezÅ‘sége dunántúli gazdaságokban

Az országos adatok alapján a sertéságazat helyzete válságos, a 11 dunántúli gazdaságra kiterjedÅ‘, 2006–2008. évek közötti felmérésünkbÅ‘l viszont megállapítható, hogy megfelelÅ‘ színvonalú, szervezettségű vágóalapanyag-termelés mellett tisztes jövedelmet lehet elérni. A vizsgálatba vont állomány (több mint 6 ezer koca és éves átlagban 100 ezer hízósertés) adatai alapján folyamatosan növekvÅ‘ termelési költségek mellett számottevÅ‘ különbség mutatkozott az integráción kívüli, illetve az iparszerű termelési rendszerhez (integrációhoz) tartozó gazdaságok eredményei között. A kocák reprodukciós teljesítménye és a takarmány értékesülés fajlagos mutatói közötti különbségek jelentÅ‘sen differenciálták a két csoporthoz tartozó gazdaságok jövedelmét, az iparszerű rendszerhez tartozók javára. -------------------------------------------------------- Nationwide data indicate that the pork industry is in crisis. Our survey of 11 farms in the Transdanubian region, done between 2006 and 2008, shows that reasonable revenues can be achieved by quality operations which are appropriately organised. The data of the animal stock covered by the research (over 6,000 sows and an average of 100,000 store-pigs a year) indicated that while production costs were continuously increasing, there was a significant difference between farms depending on whether they were part of the industrialised production system (integration). The specific indices measuring the reproductive performance of sows and the utilisation of feedstuff clearly showed the division between the two groups, and their revenues, revealing that farms belonging to the industrialised production system fared better in this regard.tartási és takarmányozási körülmények, termelési színvonal, költség-ár-jövedelem viszonyok, standards of animal keeping and feeding, quality of production, costs, prices and revenues, Livestock Production/Industries, Production Economics,

Toplinska stabilnost W1−xSix/Si višeslojeva za rendgensku optiku

The thermal stability of multilayers (MLs) for X-ray mirrors can be increased by using a pair of materials in thermodynamic equilibrium. This was achieved by doping the W-layer by Si to decrease the driving force of interdiffusion. The W0.66Si0.33/Si, W0.5Si0.5/Si, W0.33Si0.66/Si and, for comparison, W/Si MLs with ten bilayers were fabricated by electron-beam deposition in UHV onto oxidized Si substrates. The nominal thickness was 5.5 nm for Si and 2.5 nm for W or W1-xSix layers. The samples were heat treated by halogen-lamp rapid thermal annealing and by standard annealing in vacuum up to 1000 °C for 30 s and 25 min, respectively. Samples were analyzed by X-ray reflectivity and large angle X-ray diffraction measurements. From the results follows an increased stability of W1-xSix/Si MLs in comparison with the W/Si ones. The temperature which the sample can withstand without a serious damage increased from 500 to 850 °C with x increasing from 0 to 0.66 . As-deposited, MLs were amorphous. The crystalline bcc W or WSi2 phases appeared at 500 °C for x Ł 0.5. For x = 0.66, a well developed WSi2 was obtained only after annealing at 1000 °C. Hence, Si helps to keep W in the amorphous state.Primjenom parova materijala, koji se stavljaju u termodinamičku ravnotežu, može se povećati toplinska stabilnost višeslojeva za zrcala rendgenskog zračenja. Sloj volframa dopunjen je silicijem da bi se smanjila difuzija medu slojevima. Istraženi su višeslojevi W1−x Six sa x = 0.66, 0.5, 0.33 i x = 0.0 radi usporedivanja. W/Si višeslojevi sa deset dvoslojeva pripremljeni su nanošenjem uz pomoć elektronskog snopa na oksidirane Si podloge u ultravakuumu. Nominalna debljina slojeva Si bila je 5.5 nm, a W odnosno W1−xSix 2.5 nm. Višeslojevi su toplinski otpuštani. Uzorci su istraživani mjerenjem refleksivnosti i difrakcijom rendgenskog zračenja. Povećanjem x od 0 na 0.66, povisila se granična temperatura bez većeg oštećenja sa 500 na 800 ◦C

Caseinate-stabilized emulsions of black cumin and tamanu oils: preparation, characterization and antibacterial activity

Caseinate-stabilized emulsions of black cumin (Nigella sativa) and tamanu (Calophyllum inophyllum) oils were studied in terms of preparation, characterization, and antibacterial properties. The oils were described while using their basic characteristics, including fatty acid composition and scavenging activity. The oil-in-water (o/w) emulsions containing the studied oils were formulated, and the influence of protein stabilizer (sodium caseinate (CAS), 1-12 wt %), oil contents (5-30 wt %), and emulsification methods (high-shear homogenization vs. sonication) on the emulsion properties were investigated. It was observed that, under both preparation methods, emulsions of small, initial droplet sizes were predominantly formed with CAS content that was higher than 7.5 wt %. Sonication was a more efficient emulsification procedure and was afforded emulsions with smaller droplet size throughout the entire used concentration ranges of oils and CAS when compared to high-shear homogenization. At native pH of similar to 6.5, all of the emulsions exhibited negative zeta potential that originated from the presence of caseinate. The antibacterial activities of both oils and their emulsions were investigated with respect to the growth suppression of common spoilage bacteria while using the disk diffusion method. The oils and selected emulsions were proven to act against gram positive strains, mainly against Staphylococcus aureus (S. aureus) and Bacillus cereus (B. cereus); regrettably, the gram negative species were fully resistant against their action.Czech Science FoundationGrant Agency of the Czech Republic [19-16861S]; Ministry of Education, Youth and Sports of the Czech Republic - Program NPU I [LO1504]; TBU in Zlin [IGA/CPS/2019/004

INFLUENCE OF CHOICE FACTORS ON TRANSPORT SYSTEM

Článek se zabývá vlivem vybraných činností na dopravní systém a vlivem dopravního systému na některé vybrané oblasti (životní prostředí, bezpečnost, logistické služby, veřejnoprávní oblast a podobně). Článek je publikován v rámci řešení úlohy GAČR "Výzkum tvorby hodnoty pro uživatele dopravy".This article deals with influence of choice activities on transport system and influence of choice system on other areas (environment, safety, logistic services, statutory sphere etc.). This article is published within solving of GAČR “Research of formation of value for transport users)