[en] The dielectric properties of direct current (dc) magnetron sputtering aluminum silver alloy films in optical frequency have been quantitatively studied by variable angle spectroscopic ellipsometry. The structure and surface topography of the alloy films were characterized using scanning probe microscopy and x-ray diffraction. The Drude-Lorentz model was used to simulate the dielectric function of Al-Ag alloy films. Meanwhile, the effective medium theory has been utilized for the treatment of surface roughness. We found that the interband transition around 1.5 eV can be shifted through a variable annealing temperature and a changeable silver percentage of Al-Ag alloys.

[en] We report four-point IV measurements of the c-axis conductivity of mesa structures of 2212-BSCCO, using a system with sub-μs resolution along with multi-level pulses. These allow a test to be made for the presence of nonequilibrium effects. Our results suggest simple heating alone is important in measurements of this kind

[en] Performance of portable technologies from mobile phones to electric vehicles is currently limited by the energy density and lifetime of lithium batteries. Expanding the limits of battery technology requires in situ detection of trace components at electrode–electrolyte interphases. Surface-enhance Raman spectroscopy could satisfy this need if a robust and reproducible substrate were available. Gold nanoparticles (Au NPs) larger than 20 nm diameter are expected to greatly enhance Raman intensity if they can be assembled into ordered monolayers. A three-phase self-assembly method is presented that successfully results in ordered Au NP monolayers for particle diameters ranging from 13 to 90 nm. The monolayer structure and Raman enhancement factors (EFs) are reported for a model analyte, rhodamine, as well as the best performing polymer electrolyte salt, lithium bis(trifluoromethane)sulfonimide. Experimental EFs for the most part correlate with predictions based on monolayer geometry and with numerical simulations that identify local electromagnetic field enhancements. Lastly, the EFs for the best performing Au NP monolayer are between 10"6 and 10"8 and give quantitative signal response when analyte concentration is changed.

[en] By performing Z-scan method with a femtosecond laser (800 nm, 50 fs, 1 kHz), we investigated the third-order optical nonlinearities of a cuprous oxide (Cu₂O) film. Single-phase Cu₂O film deposited on a quartz substrate was obtained using the pulsed laser deposition technique. The structure properties, surface morphology and optical transmission spectrum were characterized by X-ray diffraction, scanning electron microscopy and double beam spectrophotometer, respectively. The Z-scan results show that the Cu₂O film exhibits large nonlinear refractive index, n₂ = 3 x 10^-3 cm²/GW, while the two-photon absorption coefficient, α₂ = 40 cm/GW, is relatively small. It implies that the Cu₂O film is a promising candidate for nonlinear photonic devices.

[en] To understand the origin of the multiple arc-anode attachments in the anode region of high intensity arcs, a linear stability analysis of a non-uniform argon plasma consisting of electrons, argon neutrals and singly ionized argon ions and an arc-anode interface instability analysis are performed and presented. Plasma conditions typical of the anode region of high intensity argon arcs are emphasized. The calculations have shown that small-amplitude fluctuations presented in the plasma excite two different wave modes, space-charge relaxation mode and electron thermal mode, on a time scale shorter than the one in which the multiple-attachment mode forms. The space-charge relaxation mode has been found to be stable and not affected by the non-uniformity of the plasma. The electron thermal mode can be unstable, depending on the distributions of the current flow, the electric field, the electron temperature and the electron density. The analysis, together with a consideration of the evaporation-ionization instabilities at the arc-anode interface, has been applied to previous experimental data. The observed multiple-attachment mode, consisting of several constricted attachment spots in the arc fringes, can be explained by this analysis

[en] The anode region of a high intensity argon arc has been studied experimentally. As the cold ambient gas enters, the arc-anode attachment can appear in four different modes. Besides the well-known diffuse and constricted anode attachment modes, two transition modes have been observed, namely a lift-up mode and a multiple-attachment mode. The electron temperature and the electron density distributions for these modes have been obtained with a laser Thomson scattering system, which can probe the plasma 50 μm in front of the anode surface. The measurement results show good agreement with previous Langmuir probe results. The electric field distributions for these modes have been obtained for the first time by solving the charge continuity equation. The results indicate that the entrainment of the ambient cold gas first generates a ring in the fringes of the arc, which has low electron temperatures, low electron densities and an increased electric field strength accelerating electrons towards the anode. These characteristics encourage the electron overheating instability to develop, and lead to the formation of the multiple-attachment mode. One of the constricted multiple attachments grows and takes over most of the current as more ambient gas enters to form an anode jet and a constricted mode. Moreover, directly from the electric field distributions, the anode potential fall has been calculated. A negative anode fall exists in the centres of diffuse attachments, while a positive anode fall exists in the centres of constricted attachments

[en] Highlights: • A carboxylated cellulose nanocrystal-polyethyleneimine composite (CCN-PEI) was prepared. • The as-prepared CCN-PEI was characterized by SEM, TEM, FT-IR, and XPS. • Results suggested that the reusable CCN-PEI could remove Cr(VI) from aqueous solutions with a high adsorption capacity. • The adsorption isotherm, thermodynamics, and kinetics of the adsorption process are also discussed. - Abstract: In this study, a composite adsorbent (CCN-PEI) composed of carboxylated cellulose nanocrystals (CCN) and polyethyleneimine (PEI) was prepared through an amidation reaction between the carboxyl groups of the CCN and the amine groups of the PEI. The adsorption performance of the CCN-PEI was tested by removing Cr(VI) ions from aqueous solutions. The physicochemical properties of the CCN and the Cr(VI) ion-loaded CCN-PEI were studied using scanning electron microscopy (SEM), transmission electron microscopy, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy. To investigate the adsorption kinetics of Cr(VI) ions onto this newly developed CCN-PEI, we performed experiments under different adsorption conditions, by varying the contact time, solution pH, initial Cr(VI) ion concentration, and adsorption temperature. The prepared CCN-PEI exhibited an encouraging uptake capacity of 358.42 mg × g"−"1. The adsorption process was fast: within the first 100 min, Cr(VI) ion adsorption onto the CCN-PEI was about 65%, and the adsorption equilibrium was reached within 250 min. Kinetics experiments indicated that the adsorption process could be described by a pseudo-second-order kinetic model. Furthermore, our adsorption equilibrium data fit the Langmuir isotherms well. The calculated thermodynamic parameters, such as the free energy change (ΔG = −2.93 kJ × mol"−"1), enthalpy change (ΔH = −5.69 kJ × mol"−"1), and entropy change (ΔS = −9.14 kJ × mol"−"1), indicate that the adsorption of Cr(VI) ions onto CCN-PEI was a spontaneous exothermic process. Regeneration tests indicated that CCN-PEI showed good durability and good efficiency for repeated Cr(VI) adsorptions. Based on the results obtained in this work, it can be concluded that CCN-PEI is a potentially effective adsorbent for removing Cr(VI) ions from aqueous solutions.

[en] Graphical abstract: - Highlights: • Non-genotoxic linear alkylbenzene sulfonates (LAS) generated γ-H2AX. • The γ-H2AX was not induced through direct LAS-induced DNA damage. • LAS weakened interactions between actin and DNase I. • Released DNase I translocated to nucleus and broke DNA strands, generating γ-H2AX. • This is a novel pathway for chemically induced γ-H2AX. - Abstract: Phosphorylation of histone H2AX (γ-H2AX) occurs following formation of DNA double strand breaks (DSBs). Other types of DNA damage also generate DSBs through DNA replication and repair, leading to the production of γ-H2AX. In the present study, we demonstrated that linear alkylbenzene sulfonates (LAS), the most widely used and non-genotoxic anionic surfactants, could generate γ-H2AX via a novel pathway. Breast adenocarcinoma MCF-7 cells were treated with five kinds of LAS with alkyl chains ranging from 10 to 14 carbon units (C_1_0–C_1_4LAS). The generation of DSBs and subsequent production of γ-H2AX increased in a manner that depended on the number of carbon units in LAS. γ-H2AX could also be generated with non-cytotoxic doses of LAS and was independent of the cell cycle, indicating the non-apoptotic and DNA replication-independent formation of DSBs. The generation of γ-H2AX could be attenuated by EGTA and ZnCl_2, deoxyribonuclease-1 (DNase I) inhibitors, as well as by the knockdown of DNase I. LAS weakened the interaction between DNase I and actin, and the enhanced release of DNase I was dependent on the number of carbon units in LAS. DNase I released by the LAS treatment translocated to the nucleus, in which DNase I attacked DNA and generated γ-H2AX. These results suggested that the LAS-induced generation of γ-H2AX could be attributed to the translocation of DNase I to the nucleus through the disruption of actin, and not to LAS-induced DNA damage

[en] In order to study the drying and combustion characteristics of paper sludge, some experiments were carried out in a fixed bed combustor. Results show that the drying rate of wet paper sludge (70 %-80% water content) was determined mainly by the heating temperature and sample size, and the drying rate was about 2∼5 wt %/ min under 150∼170 degree Celsius heating temperature. Because the moisture was evaporated layer by layer, the internal temperature of sludge particle was risen very slowly during the ignition stage. However, along with combustion processing inside, as the result of the heat released by sludge combustion, the internal temperature was risen even exceeding the surface temperature. These combustion and heat transfer characteristic are help to the combustion sludge. The color of sludge particle was changing from gray to dark gradually due to water evaporation, and then a layer of white shell was formed when the fixed carbon was exhausted out, which obstructed the particle size shrinking further more. The morphological change also developed step by step, showing that the combustion process was deep inside layer by layer. (author)

[en] Objective: To compare the pharmacokinetics on rabbit after left gastric regional arterial infusion chemotherapy with peripheral intravenous administration. Methods: 18 rabbits were separated into 6 time-groups at random and 5-Fu (50 mg/kg) was infused through left gastric artery. Blood of portal vein and peripheral vein were sampled at different time. Finally all rabbits were killed and partial stomach tissues were sampled. Blood and stomach tissue were analysed with high efficacy liquid chromatography after disposed. Control group members were infused 5-Fu (50 mg/kg) by ear marginal vein and then blood and stomach tissue samples taken at different times were analysed with the same method. Results: The drug concentration-time curve of portal vein and peripheral vein both reached the peak at the fifth minute after drug administration in the two methods, then declined quickly and slowed down after 30 minutes, according with two-house models. The drug concentration in portal vein of the experimental group was obviously higher than in the peripheral vein and also higher than in the portal vein of the control group maintaining for a longer period. Drug concentration in stomach tissue of experimental group was 11 times of that of control group at the fifth minute and was similar after 2 hours in both methods groups. Conclusions: Drug concentration in blood of portal vein and stomach tissue can maintain a higher level in a longer period with the same local effect after left gastric arterial infusion chemotherapy showing high chemotherapeutic efficiency