Fremlin tensor products of concavifications of Banach lattices

Suppose that $E$ is a uniformly complete vector lattice and $p_1,\dots ,p_n$ are positive reals. We prove that the diagonal of the Fremlin projective tensor product of $E_{(p_1)},\dots ,E_{(p_n)}$ can be identified with $E_{(p)}$ where $p=p_1+\dots +p_n$ and $E_{(p)}$ stands for the $p$ -concavification of $E$ . We also provide a variant of this result for Banach lattices. This extends the main result of Bu et al. (Positivity, 2013).     

A film-based wall shear stress sensor for wall-bounded turbulent flows

In wall-bounded turbulent flows, determination of wall shear stress is an important task. The main objective of the present work is to develop a sensor which is capable of measuring surface shear stress over an extended region applicable to wall-bounded turbulent flows. This sensor, as a direct method for measuring wall shear stress, consists of mounting a thin flexible film on the solid surface. The sensor is made of a homogeneous, isotropic, and incompressible material. The geometry and mechanical properties of the film are measured, and particles with the nominal size of 11 μm in diameter are embedded on the film’s surface to act as markers. An optical technique is used to measure the film deformation caused by the flow. The film has typically deflection of less than 2% of the material thickness under maximum loading. The sensor sensitivity can be adjusted by changing the thickness of the layer or the shear modulus of the film’s material. The paper reports the sensor fabrication, static and dynamic calibration procedure, and its application to a fully developed turbulent channel flow at Reynolds numbers in the range of 90,000–130,000 based on the bulk velocity and channel full height. The results are compared to alternative wall shear stress measurement methods.     

Synthesis and characterizations of ultra-small ZnS and Zn(1-x)Fe(x)S quantum dots in aqueous media and spectroscopic study of their interactions with bovine serum albumin

This work reports a new experimental methodology for the synthesis of ultra small zinc sulfide and iron doped zinc sulfide quantum dots in aqueous media. The nanoparticles were obtained using a simple procedure based on the precipitation of ZnS in aqueous solution in the presence of 2-mercaptoethanol as a capping agent, at room temperature. The effect of Fe(3+) ion concentration as dopant on the optical properties of ZnS was studied. The size of quantum dots was determined to be about 1nm, using scanning tunneling microscopy. The synthesized nanoparticles were characterized by X-ray diffraction, UV-Vis absorption and photoluminescence emission spectroscopies. The presence and amount of iron impurity in the structure of Zn((1-x))Fe(x)S nanocrystals were confirmed by atomic absorption spectrometry. A blue shift in band-gap of ZnS was observed upon increasing incorporation of Fe(3+) ion in the iron doped zinc sulfide quantum dots. The photoluminescence investigations showed that, in the case of iron doped ZnS nanoparticles, the emission band of pure ZnS nanoparticles at 427nm shifts to 442nm with appearance of a new sharp emission band around 532nm. The X-ray diffraction analysis indicated that the iron doped nanoparticles are crystalline, with cubic zinc blend structure, having particle diameters of 1.7±022nm. Finally, the interaction of the synthesized nanoparticles with bovine serum albumin was investigated at pH 7.2. The UV-Vis absorption and fluorescence spectroscopic methods were applied to compare the optical properties of pure and iron doped ZnS quantum dots upon interaction with BSA. It was proved that, in both cases, the fluorescence quenching of BSA by the quantum dots is mainly a result of the formation of QDs-BSA complex in solution. In the steady-state fluorescence studies, the interaction parameters including binding constants (K(a)), number of binding sites (n), quenching constants ( [Formula: see text] ), and bimolecular quenching rate constants (k(q)) were determined at three different temperatures and the results were then used to evaluate the corresponding thermodynamic parameters ΔH, ΔS and ΔG.     

Evaluating flood extent mapping of two hydraulic models, 1D HEC‐RAS and 2D LISFLOOD‐FP in comparison with aerial imagery observations in Gorgan flood plain,Iran

We compared flood mapping techniques using a one‐dimensional (1D) hydraulic model HEC‐RAS and two‐dimensional (2D) LISFLOOD‐FP for a 10‐km reach of Gorgan River in Iran. Both models were run using the same hydrologic input data. The input into the models was a steady discharge of 90 cm, corresponds to a flood peak occurred on March 25, 2012. Flood maps generated using these two models were compared with an observed flood inundation map, using F‐statistic. The roughness coefficients of the models were calibrated by maximizing the value of the F‐statistic. Based on the F‐statistic, LISFLOOD‐FP gives a slightly better result (F = 0.69) than HEC‐RAS (F = 0.67). Visual comparison of the flood extents generated by the two models showed reasonably good agreement. Validation was done using a flood event occurred on May 31, 2014. The LISFLOOD‐FP model gave a better result for validation as well. The 2D model showed more consistency in comparison with the 1D model.     

Simple Hydrothermal Synthesis of Nickel Hydroxide Flower-Like Nanostructures

α-Ni(OH)₂ flower-like nanostructures were successfully synthesized through one-step hydrothermal method with nickel acetate tetrahydrate, ethylene-1,2-diamine (en), hexamethylenetetramine (HMT) and cetyltrimethylammonium bromide (CTAB) as morphology-directing agents. Optimum conditions to obtain high yield and pure phase α-Ni(OH)₂ were identified by varying experimental parameters such as: en, HMT and CTAB concentration and reaction temperature. The products were characterized by X-ray diffraction, scanning electron microscopy, Fourier transform infrared and thermogravimetric analysis. These results indicated that the α-nickel hydroxide contains water molecules and anions. The hierarchical NiO nanostructures were obtained by the as-synthesized α-Ni(OH)₂ nanostructures annealed at 300 °C for 4 h.     

Methanesulfonic Acid/SiO2 as an Efficient Combination for the Synthesis of 2-Substituted Aromatic and Aliphatic Benzothiazoles from Carboxylic Acids

Methanesulfonic acid/SiO₂ (1 mL/0.3 g) was found to be as an expeditious mixture in the synthesis of 2-substituted aromatic and aliphatic benzothiazoles at 140 °C using carboxylic acids. After a simple workup, benzothiazoles were obtained in good yields. Simplicity, use of widely available and diverse carboxylic acids, and easy handling of the reaction conditions are among the benefits of the method.     

Comparison of novel pyridine-functionalized mesoporous silicas for Au(III) extraction from natural samples

A technique for solid-phase extraction utilizing pyridine-functionalized nanoporous silica (MCM-41, MCM-48 and SBA-15) was developed for the determination of gold in different samples using flame atomic absorption spectrometry. The effects of concentration and volume of eluent, pH of the solution, flow rate of extraction, sample volume and of potentially interfering ions on the efficiency of preconcentration and recovery was investigated. The limit of detection is lower than 45 pg mL^?1. Under optimal conditions, the accuracy and precision (RSD%) of the method were calculated to be >99.5% and <0.7% for the two MCMs (41 and 48) and >89.5%, and <1.5% for SBA-15, respectively. The SPE technique was used to determine the concentration of gold in natural and industrial wastewater with satisfactory results.

Very-high-resolution tandem Fabry-Perot etalon cylindrical beam volume hologram spectrometer for diffuse source spectroscopy

We demonstrate a compact and slitless spectrometer with high resolution formed by cascading a Fabry-Perot etalon (FPE) and a cylindrical beam volume hologram (CBVH). The most significant advantage of this combined spectrometer is that we can independently encode spectral information of a diffuse beam in a 2D plane. Also, we show that in this slitless configuration we can simultaneously benefit from the advantages of both elements: the high resolution of the FPE and the large spectral range of the CBVH. Here, we report on the experimental demonstration of a spectrometer with better than 0.2 nm resolution.     

Antibacterial Nanomaterials: Mechanisms,Impacts on Antimicrobial Resistance and Design Principles

Antimicrobial resistance (AMR) is one of the biggest threats to the environment and health. AMR rapidly invalidates conventional antibiotics, and antimicrobial nanomaterials have been increasingly explored as alternatives. Interestingly, several antimicrobial nanomaterials show AMR-independent antimicrobial effects without detectable new resistance and have therefore been suggested to prevent AMR evolution. In contrast, some are found to trigger the evolution of AMR. Given these seemingly conflicting findings, a timely discussion of the two faces of antimicrobial nanomaterials is urgently needed. This review systematically compares the killing mechanisms and structure-activity relationships of antibiotics and antimicrobial nanomaterials. We then focus on nano-microbe interactions to elucidate the impacts of molecular initiating events on AMR evolution. Finally, we provide an outlook on future antimicrobial nanomaterials and propose design principles for the prevention of AMR evolution.