[en] Nanostructured Ag in shapes of nanoplate, nanowire, and nanoparticle, as well as their silica gel glass composites have been prepared and characterized. Nonlinear optical (NLO) properties were measured at 532 and 1064 nm using open aperture z-scan technique and studied from the view of shape effect. NLO behaviors of the nanostructured Ag are found to be shape dependent in suspensions at both the investigated wavelengths, although they originate differently. Comparing to the mother suspensions, the Ag/silica gel glass nanocomposites present rather dissimilar NLO behaviors, which is quite interesting for further studies

[en] Three different graphene nanostructure suspensions of graphene oxide nanosheets (GONSs), graphene oxide nanoribbons (GONRs), and graphene oxide quantum dots (GOQDs) are prepared and characterized. Using a typical two-step method, the GONSs, GONRs, and GOQDs are incorporated into a polyimide (PI) matrix to synthesize graphene/PI composite films, whose nonlinear optical (NLO) and optical limiting (OL) properties are investigated at 532 nm in the nanosecond regime. The GONR suspension exhibits superior NLO and OL effects compared with those of GONSs and GOQDs because of its stronger nonlinear scattering and excited-state absorption. The graphene/PI composite films exhibit NLO and OL performance superior to that of their corresponding suspensions, which is attributed primarily to a combination of nonlinear mechanisms, charge transfer between graphene materials and PI, and the matrix effect

[en] Highlights: • miR-320 plays a significant role in chemoresistance. • This role might be attribute to targeting FOXM1. • The Wnt/β-catenin pathway also involves in this chemotherapy sensitivity. - Abstract: miR-320 expression level is found to be down-regulated in human colon cancer. To date, however, its underlying mechanisms in the chemo-resistance remain largely unknown. In this study, we demonstrated that ectopic expression of miR-320 led to inhibit HCT-116 cell proliferation, invasion and hypersensitivity to 5-Fu and Oxaliplatin. Also, knockdown of miR-320 reversed these effects in HT-29 cells. Furthermore, we identified an oncogene, FOXM1, as a direct target of miR-320. In addition, miR-320 could inactive the activity of Wnt/β-catenin pathway. Finally, we found that miR-320 and FOXM1 protein had a negative correlation in colon cancer tissues and adjacent normal tissues. These findings implied that miR-320–FOXM1 axis may overcome chemo-resistance of colon cancer cells and provide a new therapeutic target for the treatment of colon cancer

[en] A new Cs⁺ adsorbent, activated carbon loaded ammonium molybdophosphate (AMP-AC) was prepared by repeating batch reaction of H₃PO₄ and (NH₄)₆Mo₇O₂₄. The surface of the activated carbon particles was coated with AMP microcrystals through a controlled crystallization process. The X-ray diffraction (XRD) analysis identified the AMP loaded on AC with the formula of (NH₄)₃PO₄(MoO₃)₁₂.4H₂O. Scanning electron microscope images demonstrated that the fine AMP crystals was successfully immobilized and uniformly distributed on the porous carbon substrate. The effects of medium acidity, contact time, temperature and competing ions on Cs⁺ uptake by the composite were investigated. The results show that the as-prepared adsorbent keeps high selectivity and adsorption capacity (∝0.75 mmol/g) for Cs⁺ in acidic feed solution (0.1 M HNO₃). even in the presence of plentiful competing cations. Na⁺, Zn²⁺, Sr²⁺, Cr³⁺ and La³⁺, while activated carbon itself has no specific affinity for Cs⁺. The adsorption process could be described by Langmuir adsorption equations. There is no significant difference (9.4%) on Cs⁺ adsorption by the composite during system temperature changing from 298 to 348 K. (orig.)

[en] ZTA (alumina toughened by 20 wt.% zirconia), hot-pressed silicon nitride (with totally 10 wt.% Y₂O₃ and Al₂O₃ as additives) and TZP (pressureless-sintered yttria stabilized zirconia) ceramics were implanted by various doses (5 x 10¹⁶ ions/cm² ∝ 1 x 10¹⁸ ions/cm²) of Ti, Zr, and Cr ions with a MEVVA (metal vapor vacuum arc) source implanter. The bending strength of these ceramics was investigated. It was discovered that, for different ceramics, different behaviors were presented with the same doses of implantation ions. For alumina and zirconia ceramics, the bending strength increased with increasing implantation doses of Ti and Zr ions, but decreased with high dose of Cr ions. For silicon nitride ceramics, however, the bending strength originally increased with smaller doses of metals implanted, and decreased with higher doses of metals of Ti, Zr, and Cr ions. The different behaviors are correlated to the different variations in compositions and microstructures of ceramics after ion implantation. (orig.)

[en] A coaxial dielectric barrier discharge (DBD) reactor with double layer dielectric barriers has been developed for exhaust gas treatment and excited either by AC power or nanosecond (ns) pulse to generate atmospheric pressure plasma. The comparative study on the discharge characteristics of the discharge uniformity, power deposition, energy efficiency, and operation temperature between AC and ns pulsed coaxial DBD is carried out in terms of optical and electrical characteristics and operation temperature for optimizing the coaxial DBD reactor performance. The voltages across the air gap and dielectric layer and the conduction and displacement currents are extracted from the applied voltages and measured currents of AC and ns pulsed coaxial DBDs for the calculation of the power depositions and energy efficiencies through an equivalent electrical model. The discharge uniformity and operating temperature of the coaxial DBD reactor are monitored and analyzed by optical images and infrared camera. A heat conduction model is used to calculate the temperature of the internal quartz tube. It is found that the ns pulsed coaxial DBD has a much higher instantaneous power deposition in plasma, a lower total power consumption, and a higher energy efficiency compared with that excited by AC power and is more homogeneous and stable. The temperature of the outside wall of the AC and ns pulse excited coaxial DBD reaches 158 °C and 64.3 °C after 900 s operation, respectively. The experimental results on the comparison of the discharge characteristics of coaxial DBDs excited by different powers are significant for understanding of the mechanism of DBDs, reducing energy loss, and optimizing the performance of coaxial DBD in industrial applications. (paper)

[en] In this study, we obtained information from twenty-one measurement points on the stress magnitudes and orientations of a gold mine in the Ludong area. We used the overcoring technique with an improved hollow inclusion strain gauge and then analyzed the distribution characteristics of the in situ stress field. The results indicate that the stress field is characterized by σ_H > σ_h > σ_v and σ_H > σ_v > σ_h (where σ_H, σ_h, and σ_v are the maximum horizontal, minimum horizontal, and vertical principal stresses, respectively). The regional stress field is dominated by horizontal principal stress. The σ_H, σ_h, and σ_v values show a gradual increasing trend with depth. The σ_H is predominantly oriented in the NWW–SEE or near-EW direction. We also confirmed the correspondence between the measured stress field and the regional geological structure. In addition, based on the measured stress data, we discuss the implications of the in situ stress with respect to fault activity in the mine area.

[en] This paper presents an automatic test system(ATS) for the pad front-end board(pFEB) and strip front-end board(sFEB) of ATLAS small-strip Thin Gap Chamber(sTGC) detector. The pFEB is designed to readout signals of pads and wires of sTGC detector, and the sFEB is designed to readout signals of strips of sTGC detector. There will be thousands of pFEBs and sFEBs produced in mass production (including spare p/sFEBs), and all of them must pass the quality tests before delivery. To reduce the time and man power cost of the quality tests, we developed this automatic test system for mass production tests of p/sFEBs. The test system consists of a FEB Test Board(FTB), a Test Pulse Board(TPB) and a control software. The FTB connects with p/sFEB through mini-SAS cables and communicates with the control software through Gigabit Ethernet. The TPB injects external test signals to p/sFEB through GFZ. The control software provides several interfaces to set configuration parameters for p/sFEB and controls the test processes. The FTB sends configuration data to p/sFEB, and then readouts data from the them. The output data includes 4.8Gbps trigger data, 640Mbps level-1 event data, and so on. They are analyzed in FTB and then sent to the control software. The test system can automatically scan main functions and performances of p/sFEB, including channels performances, the configuration chain, the data chain, the trigger chain, etc. The specific characteristics and implementations are described in detail.

[en] A type of compact solution concentration sensor based on a microfiber with a nanoscale-structured film is proposed and demonstrated experimentally Additional loss at different solution concentrations is calculated by means of the three-dimensional finite-difference time-domain (3D-FDTD) method. The microfiber is fabricated by using the flame-heated scanning technique. Nanoscale-structured film is coated on the microfiber surface, which is assembled as a sensing unit. The sensitivity of this kind of sensor increases with the decreasing diameters of the microfiber. When the diameter of the microfiber is 2 μm, a minimum concentration sensitivity of 1% (under 450 s measuring time) is demonstrated in the experiment. Higher sensitivity can be attained when the solution concentration is higher. The sensing properties of this microfiber with the nanoscale-structured film may provide opportunities for new applications in optical sensing devices. (paper)

[en] In this paper, the numerical study has been performed on the xenon positive column discharges of mercury-free fluorescent lamp. The plasma discharge characteristics are analyzed by numerical simulation based on two-dimensional fluid model. The effects of cell geometry, such as the dielectric layer, the electrode width, the electrode gap, and the cell height, and the filling gas including the pressure and the xenon percentage are investigated in terms of discharge current and discharge efficiency. The results show that a long transient positive column will form in the xenon lamp when applying ac sinusoidal power and the lamp can operate in a large range of voltage and frequency. The front dielectric layer of the cell plays an important role in the xenon lamp while the back layer has little effect. The ratio of electrode gap to cell height should be large to achieve a long positive column xenon lamp and higher efficiency. Increase of pressure or xenon concentration results in an increase of discharge efficiency and voltage. The discussions will be helpful for the design of commercial xenon lamp cells