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The oxygen (O2)-dependent resistance change of multilayered molybdenum ditelluride (MoTe2) channels was characterized. A variation of the channel resistance could reproducibly determine relative O2...

Resin asphalt is widely used to improve the durability and thermal stability of asphalt concrete in recent years. In order to reduce the dependence of using petroleum asphalt in resin asphalt, the ...

Tanshinone IIA (Tan IIA) and sinapic acid (SA) are 2 components separately isolated from 2 Asian medicinal plants, Hydnophytum formicarum Jack and Salvia miltiorrhiza Bunge. The antitumor activities of them were worth exploring, therefore, we examined their antitumor activities in A549, HCT116, HeLa, and Colo320 cancer cell lines by means of WST-1 assay. The results show that Tan IIA exerted far higher (IC50 from 1.0 ± 0.0 to 166.3 ± 24.0 µg/mL) antiproliferative activities than SA (IC50 from 2236.3 ± 484.1 to >10 000.0 µg/mL). Of the 4 cell lines, A549 cells were the most sensitive to Tan IIA; thus, we used Western blotting to explore the cytotoxic mechanisms of Tan IIA in A549 cells and found that they rely on simultaneous induction of apoptosis and necroptosis in the cells. Apoptosis was hallmarked by the induction of cleaved caspase-3 by Tan IIA and necroptosis by the necroptotic marker proteins cyclophilin A and high mobility group box 1 (HMGB1), as well as increased lactate dehydrogenase (LDH) activities. The necroptotic effect was confirmed by the necroptosis inhibitor necrostatin-1 (Nec-1), which eliminated these effects and restored cell survival rates. The levels of cyclophilin A decreased in response to the pan-caspase inhibitor z-VAD-fmk, and those of cleaved caspase-3 decreased in response to Nec-1. Conclusively, Tan IIA has the potential to prevent lung cancer and the mechanism seems to be apoptosis and necroptosis, of which the relationship is mutually interdependent. This is the first report of Tan IIA eliciting necroptosis in A549 cells. Tan IIA may be used for necroptosis-based cancer therapy, especially to overcome apoptosis resistance.

This work was supported by the Taiwan Ministry of Science and Technology (Grant No. MOST 108-2112-M-005-012-MY3 and 109-2112-M-005-013-MY3), and also supported in part by the National Natural Science Foundation of China under Grant No. 61974070 and 61874074, 1311 Talent Plan, and Start-Up Fund from Nanjing University of Posts and Telecommunications under Grant No. NY219003, and Shenzhen Peacock Plan (Grant No. KQTD2016053112042971).

In the present study, we aim to help improve the design of van der Waals stacking, i.e., vertical 2D electronics, by probing charge transport differences in both parallel and vertical conducting channels of layered molybdenum disulfide (MoS2), with thin graphite acting as source and drain electrodes. To avoid systematic errors and variable contact contributions to the MoS2 channel, parallel and vertical electronics are all fabricated and measured on the same conducting material. Large differences in the on/off current ratio, mobility, and charge fluctuations, between parallel and vertical electronics are evident in electrical performance as well as in charge transport mechanisms. Further insights are drawn from a well-constrained analysis of both temperature-dependent current-voltage characteristics and low-frequency (LF) current fluctuations. This work offers significant insight into the fundamental understanding of charge transport and the development of future layered-materials-based integration technology.

Display Omitted The Ir-gate AlSb/InAs HEMT on Si substrate has been studied with reliability evaluation.The Ir-gate exhibited a superior metal work function.The Schottky barrier height of InAs/AlSb on silicon was improved.TEM, SIMS, and low frequency noise measurement were adopted to proof device stability. In this work, the 6-inch AlSb/InAs on Si (001) substrate is used to increase device integration and cost-effective purpose. The iridium (Ir)-gate was used for the InAs/AlSb on silicon substrate and temperature-dependent characteristics were also studied. The Ir-gate exhibited a superior metal work function which was beneficial for increasing the Schottky barrier height of InAs/AlSb on silicon heterostructures. Moreover, transmission electron microscopy, secondary ion mass spectrometry, and low frequency noise measurements were conducted to proof that the Ir-gated AlSb/InAs HEMT achieved the better stability of characteristics after self-heating and hot-carrier stresses.

A scanning light probe can locally dope two-dimensional molybdenum ditelluride, allowing monolithically integrated circuits (ICs) to be quickly written on the material.

We describe the preparation of vinyl-terminated benzoxazine-functionalized graphene using free radical grafting. The resulting functionalized graphene (f-graphene) was incorporated into bis(3-allyl-3,4-dihydro-2H-1,3-benzoxazinyl)methane (V-BF-a) monomer in order that nanocomposites could be prepared. Results of scanning electron microscopy and transmission electron microscopy revealed that the sheets of f-graphene were well dispersed throughout the matrix, and there was a strong interfacial interaction between the f-graphene and polyV-BF-a. The inclusion of f-graphene into the nanocomposites resulted in a material with a high thermal stability and a low coefficient of thermal expansion (CTE); increasing the content of f-graphene reduced the CTE significantly more. A reduction in the CTE of up to 48% was produced by adding just 1 wt% of f-graphene; this corresponded to an increase of 12 °C in the glass transition temperature. These results suggest that f-graphene nanocomposites can be ‘tuned’ to give materials with both a low CTE and a high thermal stability, and that graphene composites of this type can thus be manufactured to withstand a wider range of temperatures.

This study, part of the NCHRP 9–45 Project, analyzed the effect of mineral filler properties on asphalt mastic and the rutting potential of asphaltic mixture. The mineral filler properties were characterized by four tests: Rigden voids (RV), fineness modulus (FM), calcium oxide (CaO) content, and methylene blue value. The rheological properties of asphalt binder and mastic were characterized with the use of apparent viscosity and multiple stress creep recovery tests. Dynamic modulus and flow number tests were conducted to examine the asphaltic mixture rutting potential. The tested mixtures included several variables: four asphalt binder types, including virgin and polymer modified; two aggregate gradations; and a selected group of fillers. The study concluded that asphalt mastic performance was significantly affected by the fractional voids in the filler and possibly by the CaO content and FM. This effect, however, depended on binder type. On the one hand, the styrene–butadiene–styrene modified binder showed the strongest effect as a result of the mineral filler inclusion when tested as mastic. On the other hand, RV and CaO content showed relatively greater correlation with the mixture rutting potential, as compared with other filler properties. Addition of RV improved the prediction models for dynamic modulus and flow number. The effect of RV on the mixture rutting potential was more pronounced for the coarse mixture than for the fine mixture.

This work describes amorphous fluorinated polymer films deposited by pulsed plasma polymerizations of octafluorotoluene (PPP‐OFT) monomers on ITO glass as the hole‐injection layer of organic electroluminescent (EL) devices, in order to study the influence of sample position and duty cycle on PPP‐OFT film characteristics, and also to find a good process to yield a higher retention degree of monomers and lower roughness of PPP‐OFT fluorocarbon films. Experimental results revealed that PPP‐OFT films deposited at positions far away from the RF coil and close to the monomer inlet showed less roughness than films deposited near the high RF‐flux regions. In addition, the retention of the monomers in the PPP‐OFT layer will be high if the deposition is conducted near the monomer inlet but some distance away from the RF electrode. Moreover, amorphous fluorinated polymer films can be deposited with higher fluorine to carbon (F/C) ratios and CF2 contents at proper substrate positions by means of different st...

Tunability and stability in the electrical properties of 2D semiconductors pave the way for their practical applications in logic devices. A robust layered indium selenide (InSe) field-effect transistor (FET) with superior controlled stability is demonstrated by depositing an indium (In) doping layer. The optimized InSe FETs deliver an unprecedented high electron mobility up to 3700 cm2 V-1 s-1 at room temperature, which can be retained with 60% after 1 month. Further insight into the evolution of the position of the Fermi level and the microscopic device structure with different In thicknesses demonstrates an enhanced electron-doping behavior at the In/InSe interface. Furthermore, the contact resistance is also improved through the In insertion between InSe and Au electrodes, which coincides with the analysis of the low-frequency noise. The carrier fluctuation is attributed to the dominance of the phonon scattering events, which agrees with the observation of the temperature-dependent mobility. Finally, the flexible functionalities of the logic-circuit applications, for instance, inverter and not-and (NAND)/not-or (NOR) gates, are determined with these surface-doping InSe FETs, which establish a paradigm for 2D-based materials to overcome the bottleneck in the development of electronic devices.

In this study, we investigate the chemical properties and surface morphology of super-hydrophobic (SH) films deposited by self-assembled RF atmospheric-pressure plasma (APP) deposition system. The O2/HMDSN (hexamethyldisilazane) and Ar serve as the deposition precursor and ionization gas, respectively. The effects of process parameters, including the oxygen flow rate and the nozzle-to-sample distance on the characteristics of SiOx films measured by FTIR, XPS, SEM and AFM are also discussed. It was found that the higher deposition rate was obtained at higher oxygen flow rate conditions. Consequently, the smooth surface was transformed into a rough surface with many particles when the nozzle-to-sample distance was decreased from 20 mm to 10 mm. The SH films (contact angle over 150° and sliding angle below 5°) were obtained when the nozzle-to-sample distance was 10 mm. A simplified deposition mechanism is proposed to explain the effect of process parameters on the films that are formed.

In this study, super-hydrophobic films were deposited in a one-step simple process by pulsed RF C6F6 plasma, and the influence of the duty-cycle (DC) on the surface structure and chemical characteristics of depositing fluorocarbon films was examined. The deposited coatings were analyzed by X-ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared Spectrometry (FTIR), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Contact Angle Analyzer. It was found that by decreasing the DC from 1 to 0.1, the rough structure of the film with a lot of particles was obtained. In addition, the super-hydrophobic property was obtained on this composite fluorocarbon film. Finally, the adhesion of fluorocarbon films could be increased by deposited on the cotton fiber substrates instead of Si wafer.

Precisely controllable and reversible p/n-type electronic doping of molybdenum ditelluride (MoTe2 ) transistors is achieved by electrothermal doping (E-doping) processes. E-doping includes electrothermal annealing induced by an electric field in a vacuum chamber, which results in electron (n-type) doping and exposure to air, which induces hole (p-type) doping. The doping arises from the interaction between oxygen molecules or water vapor and defects of tellurium at the MoTe2 surface, and allows the accurate manipulation of p/n-type electrical doping of MoTe2 transistors. Because no dopant or special gas is used in the E-doping processes of MoTe2 , E-doping is a simple and efficient method. Moreover, through exact manipulation of p/n-type doping of MoTe2 transistors, quasi-complementary metal oxide semiconductor adaptive logic circuits, such as an inverter, not or gate, and not and gate, are successfully fabricated. The simple method, E-doping, adopted in obtaining p/n-type doping of MoTe2 transistors undoubtedly has provided an approach to create the electronic devices with desired performance.

Polypropylene (PP) films have been widely used in many industrial areas, such as for protective overcoats and food packaging. However, PP film’s hydrophobic surface properties induce poor wettability and adhesion; these properties have restrained the application of these films. Many surface modification techniques like wet-chemical treatment, UV irradiation, and plasma (including the atmospheric-pressure plasma, APP) treatment have been applied to films to enhance their hydrophilic properties. Among these technologies, APP treatment has attracted much attention due to its dry process, low vacuum equipment cost, and high productivity.

A novel plasma system based on double-pipe method was generated for the development of an atmospheric-pressure-plasma jet (APPJ). This APPJ deposits homogeneous thin films without unfavorable contamination in plasma source. The experimentally measured gas-phase temperature of the argon APPJ maintained at RF electric power was around 40degC-80degC, indicating this APPJ to be a low-temperature plasma. This plasma system will provide a chamber less deposition for coating application.