The absorption,fluorescence and phosphorescence spectra of α and β-F,Cl, Br-naphthalenes in crystalline matrixes at 77 K

The paper studies the absorption, fluorescence and phosphorescence spectra of α and β-F, Cl, Br-naphtalenes (α, β-F, Cl,BrN) in different matrixes at 77 K and different concentrations. From these spectra one obtaines the vibrational frequences.     

Cannabis-Derived Compounds Cannabichromene and Δ9-Tetrahydrocannabinol Interact and Exhibit Cytotoxic Activity against Urothelial Cell Carcinoma Correlated with Inhibition of Cell Migration and Cytoskeleton Organization

Cannabis sativa contains more than 500 constituents, yet the anticancer properties of the vast majority of cannabis compounds remains unknown. We aimed to identify cannabis compounds and their combinations presenting cytotoxicity against bladder urothelial carcinoma (UC), the most common urinary system cancer. An XTT assay was used to determine cytotoxic activity of C. sativa extracts on T24 and HBT-9 cell lines. Extract chemical content was identified by high-performance liquid chromatography (HPLC). Fluorescence-activated cell sorting (FACS) was used to determine apoptosis and cell cycle, using stained F-actin and nuclei. Scratch and transwell assays were used to determine cell migration and invasion, respectively. Gene expression was determined by quantitative Polymerase chain reaction (PCR). The most active decarboxylated extract fraction (F7) of high-cannabidiol (CBD) C. sativa was found to contain cannabichromene (CBC) and Δ9-tetrahydrocannabinol (THC). Synergistic interaction was demonstrated between CBC + THC whereas cannabinoid receptor (CB) type 1 and type 2 inverse agonists reduced cytotoxic activity. Treatments with CBC + THC or CBD led to cell cycle arrest and cell apoptosis. CBC + THC or CBD treatments inhibited cell migration and affected F-actin integrity. Identification of active plant ingredients (API) from cannabis that induce apoptosis and affect cell migration in UC cell lines forms a basis for pre-clinical trials for UC treatment.     

A collapsing bubble-induced microinjector: an experimental study

In this study, a new drop-on-demand actuation mechanism, which uses an oscillating bubble as actuator is proposed and its feasibility is investigated via the consideration of two important design parameters, namely, bubble distance to free surface and nozzle dimension. The droplet ejection process captured using high-speed photography technique shows that such an actuation mechanism has interesting features and perhaps some advantages over the conventional ones (thermal bubble, piezoelectric, etc.) employed in inkjet printers such as the ejection of a droplet free of satellite droplets and others.     

PVA-Based Sol–Gel Synthesis and Characterization of CdO–ZnO Nanocomposite

CdO–ZnO nanocomposite was fabricated by a sol–gel pyrrolysis method based on the poly vinyl alcohol (PVA) polymeric network. The prepared nanocomposite was carefully characterized using scanning electron microscopy, X-Ray dispersive energy analysis, ICP-atomic emission spectroscopy, X-Ray diffraction, transmission electron microscopy and UV–visible spectroscopy. The structure, composition, and morphology of this composite depend on a number of aspects: the amounts of cadmium salt, zinc salt, and PVA in the initial solution, the solvent composition, and the pyrrolysis temperature. The obtained results showed that the nanocomposite had excellent linear nanoclusters created from nanograins. Each nanograin was made of a CdO core, completely covered by ZnO layers. Total diameter of each nanograin was 70–90 nm.     

Tunability of temperature-dependent absorption in a graphene-based hybrid nanostructure cavity

Enhanced absorption is obtained in a hybrid nanostructure composed of graphene and one-dimensional photonic crystal as a cavity in the visible wavelength range thanks to the localized electric field around the defect layers. The temperature-induced wavelength shift is revealed in the absorption spectra in which the peak wavelength is red-shifted by increasing the temperature. This temperature dependence comes from the thermal expansion and thermo-optical effects in the constituent layers of the structure. Moreover, the absorption peaks can be adjusted by varying the incident angle. The results show that absorption is sensitive to TE/TM polarization and its peak values for the TE mode are higher than the TM case. Also, the peak wavelength is blue-shifted by increasing the incident angle for both polarizations. Finally, the possibility of tuning the absorption using the electro-optical response of graphene sheets is discussed in detail. We believe our study may be beneficial for designing tunable graphene-based temperature-sensitive absorbers.     

Non-self mappings in modular spaces and common fixed point theorems

The aim of this paper, is to introduce the convex structure (specially, Takahashi convex structure) on modular spaces. Moreover, we are interested in proving some common fixed point theorems for non-self mappings in modular space.     

Application of graphene nanoplatelets silica composite,prepared by sol–gel technology,as a novel sorbent in two microextraction techniques

In this study, the application of a novel nanomaterial composite was investigated in two microextraction techniques of solid‐phase microextraction and a needle trap device in a variety of sampling conditions. The optimum sampling temperature and relative humidity were 10°C and 20%, respectively, for both techniques with two sorbents of graphene/silica composite and polydimethyl siloxane. The two microextraction techniques with the proposed sorbent showed recoveries of 95.2 and 94.6% after 7 days. For the needle trap device the optimums desorption time and temperature were 3 min at 290°C and for SPME these measures were 1 and 1.5 min at 240–250°C for the graphene/silica composite and polydimethyl siloxane, respectively. The relative standard division obtained in inter‐ and intra‐day comparative studies were 3.3–14.3 and 5.1–25.4, respectively. For four sample the limit of detection was 0.021–0.25 ng/mL, and the limit of quantitation was 0.08–0.75 ng/mL. The results show that the graphene/silica composite is an appropriate extraction media for both techniques. Combining an appropriate sorbent with microextraction techniques, and using these in conjunction with a sensitive analytical instrument can introduce a strong method for sampling and analysis of occupational and environmental pollutants in air.     

Plasma-assisted nitrogen doping of VACNTs for efficiently enhancing the supercapacitor performance

Nitrogen doping of vertically aligned carbon nanotubes (VACNTs) using plasma-enhanced chemical vapour deposition has been investigated to improve the supercapacitance performance of CNTs. Incorporating electrochemical measurements on the open-ended nitrogen-doped CNTs, showed the achievement of 6 times improvement in the capacitance value. For nitrogen-doped CNTs on silicon substrate, specific capacitance of 60 F g^?1 was obtained in 0.5 M KCl solution, with capacity retention ratio above 90 % after cycled at 0.1 A g^?1 for 5000 cycles. Using this sample, a symmetric supercapacitance was fabricated which showed the power density of 37.5 kW kg^?1. The facile fabrication approach and its excellent capacitance improvement, propose it as an efficient technique for enhancing the supercapacitance performance of the carbon-based electrodes.     

Detonatlve travelling waves for combustions

The existence of travelling wave solution to equations of a viscous heat conducting combustible fluid is proved. The reactions are assumed to be one step exothermic reactions with a natural discontinuous reaction rate function. The problem is studied for a general gas. Instead of assuming the ideal gas conditions we consider a general thermodynamics which is described by a fairly mild set of hypotheses. Travelling waves for detonations reduce to specific heteroclinic orbits of a discontinuous system of ODE's. The existence proof for heteroclinic orbits corresponding to weak and strong detonation waves is carried out by some general topological arguments in ODE. The uniqueness and nonuniqueness of these waves are also considered.     

Spark-generated bubble collapse near or inside a circular aperture and the ensuing vortex ring and droplet formation

This paper aims to study the oscillation of a sparkgenerated submerged bubble located near or inside a circular aperture made in a flat plate using high-speed visualization technique. In the case of a bubble oscillating near an aperture the initial free surface of the water was set at the bottom surface of the plate. The effects of aperture size and bubblefree surface distance on the bubble behavior as well as on the ensuing droplet dynamics are investigated. It was found that the direction of the bubble reentrant jet was towards the aperture or away from it respectively when the normalized aperture size was smaller or greater than a certain critical value. In addition, a toroidal vortex ring was observed to form, which rotated inwards as it moved away from the aperture. It was also found that if the bubble was incepted at a distance sufficiently away from a supercritical size aperture a single droplet could be produced. In the case of a bub- ble initiated in the middle of a circular aperture submerged just beneath the water free surface, the bubble was found to take the shape of an ellipsoid during its expansion. Then a reentrant jet was initiated and pierced the bubble from its top side.