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In this paper, a promising method for growing large-sized and high-quality Mg2SiO4 single crystals was explored, and a transparent Mg2SiO4 single crystal, 30 mm in diameter and 80 mm in length, was successfully grown by the Czochralski method. The morphology of dislocation was studied by chemical etching and explained by surface energy based on the density functional theory (DFT) method. And the anisotropy of its thermodynamic and optical properties was studied. The experimental results showed a maximum Mohs hardness of 6.84 and the highest thermal conductivity of 11.73 W m−1 K−1, indicating that Mg2SiO4 has higher hardness and better thermal properties. Furthermore, the refractive index curves along the three principal axes in the range of 200–1700 nm and transmittance curves in the range of 200–2500 nm were obtained. The maximum phonon energy of the Mg2SiO4 crystal was determined. Finally, the band structure and density of states (DOS) were calculated based on the DFT method. These results provide an important reference for the application of Mg2SiO4 as a near-infrared tunable laser crystal host. [ABSTRACT FROM AUTHOR]

An efficient gene transfer and expression tool is lacking for shrimps and shrimp cells. To solve this, this study has developed a shrimp DNA virus-mediated gene transfer and expression system, consisting of insect Sf9 cells for viral packaging, the shrimp viral vector of pUC19-IHHNV-PH-GUS and the baculoviral vector of Bacmid or Bacmid-VP28 encoding the shrimp WSSV envelope protein VP28. The pUC19-IHHNV-PH-GUS vector was constructed by assembling the genomic DNA of shrimp infectious hypodermal and hematopoietic necrosis virus (IHHNV), which has shortened inverted terminal repeats, into a pUC19 backbone, and then an expression cassette of baculoviral polyhedron (PH) promoter-driven GUS (β-glucuronidase) reporter gene was inserted immediately downstream of IHHNV for proof-of-concept. It was found that the viral vector of pUC19-IHHNV-PH-GUS could be successfully packaged into IHHNV-like infective virions in the Sf9 cells, and the gene transfer efficiency of this system was evaluated and verified in three systems of Sf9 cells, shrimp hemolymph cells and tissues of infected shrimps, but the GUS expression could only be detected in cases where the viral vector was co-transfected or co-infected with a baculovirus of Bacmid or Bacmid-VP28 due to the Bacmid-dependence of the PH promoter. Moreover, the packaging and infection efficiencies could be significantly improved when Bacmid-VP28 was used instead of Bacmid. [ABSTRACT FROM AUTHOR]

Large size laser crystals are a key component of high-power all solid-state lasers. However, during the crystal growth process, defects such as bubbles and inclusions are inevitably generated, which affect the performance of the laser. In order to quickly and effectively evaluate crystal defects, a three-dimensional imaging system for crystal defects based on sheet beam scanning was established in this paper. In the system, a Powell lens is used to shape a 532 nm point laser to obtain a sheetlike laser. The scattered light generated by crystal defects is obtained through a telecentric lens and CMOS detector to obtain the surface distribution of crystal defects. At the same time, high-precision displacement platforms are used to scan the surface array one by one, completing the three-dimensional distribution scanning of the crystal. Furthermore, combined with digital image processing technology, characterize the surface distribution characteristics of crystal defects and reconstruct the volume distribution characteristics of crystal defects. Based on the above system, intrinsic defects in Yb:YAG crystals with dimensions of about 50 mm x 50 mm x 100 mm were measured with a minimum defect detection resolution of 38. 69 μm. This article provides a new method for accurately characterizing the internal defects of crystals, and also provides visual data support for high-precision processing of crystal billets in the later stage. [ABSTRACT FROM AUTHOR]

Addressing the treatment of complex industrial wastewater continues to be a substantial challenge within the realm of water treatment. A biofilm reactor was engineered, integrating lotus stem biochar, lotus stem biological filler, and the ZW5 strain for enhanced wastewater treatment. The removal efficiencies of nitrate (NO 3 - -N), calcium (Ca 2+ ), chemical oxygen demand (COD), phosphorus (PO 4 3- -P), plumbum (Pb 2+ ), and carbamazepine (CBZ) were 98.46, 81.08, 91.79, 96.63, 97.75, and 99.26% when HRT was 3 h, pH was 7.0, Pb 2+ , CBZ, and influent salinity contents were 15.0, 3.0, and 1500 mg L -1 . The reactor effectively fixed the microorganisms and provided a good microenvironment and niche, which was conducive to the adsorption of Pb 2+ and CBZ by microorganisms and biominerals. Furthermore, the modified biochar in the reactor filler facilitated microbial metabolism and enabled indirect electron transfer. Microorganisms altered their dominant community structure in response to Pb 2+ and CBZ exposure. Microorganisms maintained efficient activity through synergy and direct electron transfer through nanowires. The reactor serves as a model for pollutant removal from complex industrial wastewater, leveraging the multifaceted use of lotus stems and microbial-induced calcium precipitation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)