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Polarization-sensitive photodetection and imaging have great application value in fields such as polarization division multiplexing optical communication, remote sensing, near-field imaging and military monitoring. Pursuing a high polarization ratio has always been the research hotspot in polarization-sensitive photodetectors. In this paper, we report a compression strain enhanced polarization ratio in β-gallium oxide (β-Ga2O3) single crystal flake. A rigorous crystallographic analysis confirmed its high crystalline quality and orientation. Angle-resolved polarization Raman spectroscopy (ARPRS) was adopted to study the anisotropy of its optical properties. Extensive ARPRS measurements and theoretical calculation consistently demonstrate the strong optical anisotropy in the high-quality β-Ga2O3 flake. A polarization ratio of 0.96 was obtained in the flat β-Ga2O3 flake. Furthermore, mechanical strain of ±0.7% was introduced into β-Ga2O3. An increased polarization ratio of 0.98 was achieved in the case of 0.7% compression strain, which is, to the best of our knowledge, the highest value for UVC polarization-sensitive photodetectors. That corresponds to an improved polarization rejection ratio of 100. This work proposed a new path towards improving polarization sensitivity by applying strain engineering in the active material. [ABSTRACT FROM AUTHOR]

Recently, the optoelectronic memory is capturing growing attention due to its integrated function of sense and memory as well as multilevel storage ability. Although tens of states have been reported in literature, there are still three obvious deficiencies in most of the optoelectronic memories: large programming voltage (>20 V), high optical power density (>1 mW cm−2), and poor compatibility originating from the over-reliance on channel materials. Here, we firstly propose an optoelectronic memory based on a new photosensitive dielectric (PSD) architecture. Data writing and erasing are realized by using an optical pulse to switch on the PSD. The unique design enables the memory to work with a programming voltage and optical power density as low as 4 V and 160 µW cm−2, respectively. Meanwhile, this device may be extended to different kinds of transistors for specific applications. Our discovery offers a brand-new direction for non-volatile optoelectronic memories with low energy consumption. Designing high efficient optoelectronic memory remains a challenge. Here, the authors report a novel optoelectronic memory device based on a photosensitive dielectric that is an insulator in dark and a semiconductor under irradiation with multilevel storage ability, low energy consumption and good compatibility. [ABSTRACT FROM AUTHOR]

Nanoscale zero-valent iron (nZVI) has a high removal affinity toward arsenic (As). However, the agglomeration of nZVI reduces the removal efficiency of As and, thus, limit its application. In this study, we report an environmentally friendly novel composite of Chlorella vulgaris–supported nanoscale zero-valent iron (abbreviated as CV-nZVI) that exhibits a fast and efficient removal of As(III) from As-contaminated water. Scanning electron microscopy–energy-dispersive spectroscopy (SEM–EDS), X-ray diffractometry (XRD), attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR), and X-ray photoelectron spectroscopy (XPS) were used to characterize and analyze the CV-nZVI. These results indicated that the stabilization effect of C. vulgaris reduced the nZVI agglomeration and enhanced the reactivity of nZVI. The experiments showed a removal efficiency of 99.11% for As(III) at an optimum pH of 7.0. The adsorption kinetics and isotherms followed the pseudo-second-order kinetic model and Langmuir adsorption isotherm with the superior maximum adsorption capacities of 34.11 mg/g for As(III). The FTIR showed that the As(III) was adsorbed on the CV-nZVI surface by complexation reaction, and XPS indicated that oxidation reaction was also involved. After five reuse cycles, the removal efficiency of As(III) by CV-nZVI was 32.93%, suggesting that the CV-nZVI had some reusability and regeneration. Overall, this work provides a practical and highly efficient approach for As remediation in As-contaminated water, and simultaneously resolves the agglomeration problems of nZVI nanoparticles. [ABSTRACT FROM AUTHOR]

Cephalosporin antibiotics, a group of widely prescribed antibiotics, are frequently detected in wastewater effluent and in the natural aquatic environment. Materials have been sought to effectively degrade the antibiotics. In this study, a novel high-iron clay was prepared with potassium ferrate and montmorillonite via a strong alkaline in situ synthesis method. Degradation of cefazolin sodium (CFZ) by this novel Fe (VI)-clay was investigated. The optimal conditions for the degradation of CFZ were determined using a single factor experiment and response surface optimization method. We found that 89.84% removal efficiency was obtained in 137 min when pH value was 5.16 and Fe (VI)-clay dosage was 0.79 g. The CFZ degradation mechanism was studied by computations on the Frontier Electron Density (FED) in combination with spectroscopic and mass spectroscopic analysis. The spectroscopic characteristics of the products at different stages showed that the oxidation decomposition reaction occurred during the degradation of CFZ by Fe (VI)-clay. Furthermore, FED calculation combined with GC–MS results showed that the degradation pathways of CFZ by the Fe (VI)-clay was mainly the cleavage of β-lactam, thiadiazole, tetrazole, and dihydrothiazine rings. [ABSTRACT FROM AUTHOR]

A potentially fatal microsporidial infection targeting the skeletal muscles of the tiger barb Puntius tetrazona was described. Ultrastructural and molecular analyses of infected tissues confirmed that the causative parasite was Pleistophora hyphessobryconis. Compared to P. hyphessobryconis observed in other hosts, those infecting tiger barb demonstrated differences in ultrastructure that may be related to host adaptation. Phylogenetic analysis revealed that classifications based on different methods of analysis (molecular, morphologic, or developmental) do not always coincide, and suggesting that the genetic relationships between Pleistophora and Ovipleistophora may need to be redefined. Transparent mutants of tiger barb can be artificially infected by P. hyphessobryconis, and the dynamic process and spatial distribution of P. hyphessobryconis infection can be observed in real time. These transparent fish mutants are a valuable model to study microsporidial infection in vivo. [ABSTRACT FROM AUTHOR]

We discovered a technical solution of such outstanding importance that it can trigger new approaches in silicon wet etching processing and, in particular, photovoltaic cell manufacturing. The so called inverted pyramid arrays, outperforming conventional pyramid textures and black silicon because of their superior light-trapping and structure characteristics, can currently only be achieved using more complex techniques involving lithography, laser processing, etc. Importantly, our data demonstrate a feasibility of inverted pyramidal texturization of silicon by maskless Cu-nanoparticles assisted etching in Cu(NO3)2 / HF / H2O2 / H2O solutions and as such may have significant impacts on communities of fellow researchers and industrialists. [ABSTRACT FROM AUTHOR]