Prevalence of Coxiella burnetii infection in dairy cattle with reproductive disorders

The prevalence of Coxiella burnetii infection in 207 cattle with reproductive disorders was studied by using an indirect immunofluorescence (IF) test, nested polymerase chain reaction (PCR) and isolation. IF antibodies to phase I and phase II antigens of C. burnetii were found in 122 (58.9%) and 125 (60.4%) of the sera, respectively, and PCR-positives were found in 8 (3.9%) of the sera and in 51 (24.6%) of the milk samples. In addition, C. burnetii was isolated from 51 (24.6%) of the milk samples by inoculating laboratory mice. The results indicate that the IF test plus PCR are useful in the diagnosis of bovine coxiellosis. It is difficult to deny that dairy cattle with reproductive disorders would be one of the important reservoirs of C. burnetii responsible for infection in both animal and human populations in Japan.     

Diffusion barrier properties of ionized metal plasma deposited tantalum nitride thin films between copper and silicon dioxide

Tantalum nitride thin films with different thickness are sputtered deposited on silicon dioxide in the Cu/TaN/SiO₂/Si multiplayer structure. Using resistivity analyses, X-ray diffraction, scanning electron microscopy and Rutherford backscattering spectroscopy, this work examines the impact of varying layer thickness on the crystal structure, resistivity, intermixing and reactions at the interfaces before and after annealing. The thinner the film thickness of TaN, the severe the reactions at the interface of Cu/TaN and consumed more conductive Cu. All the structures shown similar degradation process, and were found to be stable up to 500°C for 35 min. Accelerated grain growth and agglomeration were also observed after annealing temperature higher than 550°C at all Cu surfaces of the samples.     

Scandium extraction from sulfuric acid solutions by mixtures of D2EHPA and MTAA sulfate in toluene

Theoretical Foundations of Chemical Engineering - The extraction of scandium from solutions of the waste of sulfuric-acid leaching from the magnetic separation of titanomagnetites via toluene...     

Fermentation of texturized vegetable proteins extruded at different moisture contents: effect on physicochemical,structural, and microbial properties

Food Science and Biotechnology - To investigate the effect of fermentation on texturized vegetable protein (TVP), TVPs extruded at 40 and 50% feed moisture contents (MC) were fermented using...     

Characterization of in-situ terahertz detection by optical interaction in a periodically poled stoichiometric lithium tantalate nonlinear crystal

Terahertz waves are generated using a femtosecond laser pulse in a periodically poled stoichiometric lithium tantalate crystal and simultaneously detected via a non-collinear optical parametric interaction inside the same crystal. Real time up-conversion signal between the generated THz and an optic probe pulses is measured depending on the beam overlapped conditions using a general silicon-photodiode for the THz detection. The non-collinear geometry is to facilitate manipulated property of the position-dependent bandwidth at narrow and broad bandwidths of 45 GHz and 3.3 THz, respectively at the one crystal. Furthermore, an aperture effect at the detection part is characterized as the function of size and position owing to the spatial distribution of the frequency conversion signal and it is applied in optimization of the in-situ detection scheme.     

Effect of heat transfer on the C49–C54 phase transformation in TiSi2 thin film

In this paper, the effect of heat transfer on the C49–C54 phase transformation in TiSi₂ thin film was investigated for the first time. Variation of the height of the chamber in the furnace during the annealing process was found to affect the sheet resistance (Rs) value of TiSi₂. By employing a moderate height of the annealing chamber, which makes it possible for the gas molecules inside to be more turbulent, the reduction of Rs can be achieved. From the standpoint of heat transfer theory, it has been proved in this paper that the enhancement of the thermal energy exchange between the wafer and the surrounding ambient contributes to the low resistivity C54 phase formation.     

分子筛附载纳米TiO2催化降解有机磷农药废水

对分子筛附载纳米TiO_2光催化降解有机磷农药废水进行了研究。实验表明,附载纳米TiO_2分子筛的光催化作用主要是纳米TiO_2所致,控制初始pH值、添加H_2O_2都可以更好的提高其催化效果。所制得的附载分子筛牢固性好,活性寿命长,具有一定的应用价值。     

Erratum

Epitaxial layers of ZnSe ranging in thickness from 5μm to 30 μm have been grown on GaAs (100) substrates over the temperature range 240° C to 340° C by atmospheric pressure MOVPE employing dimethylzinc and hydrogen selenide. An optimum growth temperature of 280 ± 5° C has been identified and when grown at this temperature the ZnSe epitaxial layers exhibit low resistivity (ρ _{298 K} ≤ 10 ohm · cm), a low compensation ratio (θ _{298 K} = 0.27), a carrier mobility (μ _{298 K} ) of 250 ±10 cm ² V ^-1 s ^-1 ) and are n -type ( n _{298 K} = 8.0 × 10 ¹⁴ cm ^-3 ). The ratio of photoluminescence intensity measured at 298K and at 12 K is high (10 ⁴ ) and is dominated by a sharp emission due to excitons bound to neutral donors at 2.7956 eV. Mass spectrometric investigations of the chemical reactions occurring inside the reactor in the presence of the GaAs substrate indicate significant surface-controlled reactivity in the region of 280° C. The online version of the original article can be found at     

The growth and characterization of InP-based multiquantum wells and multilayer structures

The structural and optical properties of GaInAs/InP multiquantum well (MQW) structures grown either continuously or with growth pauses has been studied. TEM, photoluminescence and absorption spectroscopy have shown that excellent quality MQWs are produced by both continuous or paused growths. Typical 10 K photoluminescence linewidths of 5–6 meV were obtained for 30 to 180 period structures. The reproducibility and uniformity of these MQW structures has also been demonstrated with wavelength variations of 8 nm recorded over full 2′ substrates. Optical modulators fabricated from these structures have shown contrast ratios up to 3.6 dB. The use of GaAlInAs/InP multi-layer structures as high reflectivity mirrors has been demonstrated for incorporation into high contrast ratio reflective modulators and surface emitting lasers.