Transmission of Oyster Mushroom Spherical Virus to Progeny via Basidiospores and Horizontally to a New Host Pleurotus floridanus.

Mycoviruses are usually transmitted horizontally via hyphal anastomosis and vertically through sporulation in natural settings. Oyster mushroom spherical virus (OMSV) is a mycovirus that infects Pleurotus ostreatus, with horizontal transmission via hyphal anastomosis. However, whether OMSV can be vertically transmitted is unclear. This study aimed to investigate the transmission characteristics of OMSV to progeny via basidiospores and horizontally to a new host. A total of 37 single-basidiospore offspring were obtained from OMSV-infected P. ostreatus and Pleurotus pulmonarius for Western blot detection of OMSV. The OMSV-carrying rate among monokaryotic isolates was 19% in P. ostreatus and 44% in P. pulmonarius. Then, OMSV-free and OMSV-infected monokaryotic isolates were selected for hybridization with harvested dikaryotic progeny strains. Western blot analyses of the offspring revealed that the OMSV transmission efficiency was 50% in P. ostreatus and 75% in P. pulmonarius, indicating vertical transmission via sexual basidiospores. Furthermore, we observed the horizontal transfer of OMSV from P. pulmonarius to Pleurotus floridanus. OMSV infection in P. floridanus resulted in significant inhibition of mycelial growth and yield loss. This study was novel in reporting the vertical transmission of OMSV through basidiospores, and its infection and pathogenicity in a new host P. floridanus.

All-silicon polarization-independent broadband achromatic metalens designed for the mid-wave and long-wave infrared.

Metasurfaces demonstrate excellent capabilities in manipulating the phase, amplitude and polarization of light. Metalens, as a typical kind of metasurface devices, shows great prospect in simplifying imaging systems. However, like diffractive optical elements, intrinsic dispersion of metasurfaces is high. Thus, significant chromatic aberration is present in common metalenses, deteriorating imaging quality under broadband illumination condition and limiting their applications. To tackle this problem, broadband achromatic metalenses have been proposed and demonstrated in the visible and near-infrared wavelength regions so far. However, broadband achromatic metalens working in the mid-wave and long-wave infrared is still rare. In this paper, thanks to the ingenious design of meta-units that provide the required local phase and phase dispersion, several all-silicon broadband achromatic metalenses working in the mid-wave infrared (3-5 µm) or long-wave infrared (8-14 µm) wavelengths are proposed. Numerical simulation results demonstrate that the designed broadband achromatic metalenses can provide a near-constant focal length with small deviations and an average focusing efficiency of about 70% over the whole operation bandwidths. In addition, these metalenses hold near diffraction-limited focusing capability and polarization-independent focusing features. The achromatic metalenses proposed here are beneficial for improving imaging quality under broadband illumination and increasing detection efficiency of mid-wave and long-wave infrared detection systems.

Adsorption of Pd(II) ions by electrospun fibers with effective adsorption sites constructed by N, O atoms with a particular spatial configuration: Mechanism and practical applications.

The separation and recovery of palladium from electronic waste (e-waste) are of great significance as they can alleviate environmental pollution and avoid resource loss. Herein, a novel nanofiber modified by 8-hydroxyquinoline (8-HQ-Nanofiber) with adsorption sites co-constructed by N and O atoms of hard bases was fabricated, which has good affinity properties for the Pd(II) ions belonging to soft acid in the leachate of e-waste. The adsorption mechanism of 8-HQ-Nanofiber for Pd(II) ions was revealed from the perspective of molecular level relied on a series of characterizations, such as FT-IR, ss-NMR, Zeta potential, XPS, BET, SEM and DFT. The adsorption of Pd(II) ions on 8-HQ-Nanofiber reached equilibrium within 30 min and the maximum uptake capacity was 281 mg/g at 318.15 K. The adsorption behavior of Pd(II) ions by 8-HQ-Nanofiber was described by the pseudo-second-order and Langmuir isotherm models. The 8-HQ-Nanofiber exhibited relatively good adsorption performance after 15 times of column adsorption. Finally, based on hard and soft acids and bases (HSAB) theory, a strategy to regulate the Lewis alkalinity of adsorption sites by specific spatial structures is proposed, which provides a new direction for the design of adsorption sites.

Large-Scale Wideband Light-Trapping Black Silicon Textured by Laser Inducing Assisted with Laser Cleaning in Ambient Air.

Black silicon, which is an attractive material due to its optical properties, is prepared mainly by laser inducing in an SF6 atmosphere. Considering the effect of SF6 gas on the environment and human health, here we propose an efficient, economical, and green approach to process large-scale black silicon. In the wavelength range of 0.3-2.5 µm, the role of air could replace SF6 gas to texture black silicon by laser inducing with appropriate processing parameters. Then, to extend the working window of its excellent light-trapping status, laser-plasma shockwave cleaning was introduced to eliminate the deposition and improve the structures and morphology. The results revealed that the micro-nano structures became higher, denser, and more uniform with increasing cleaning times and deteriorating cleaning velocity, which compensated for the role of S atoms from the ambient SF6. Moreover, absorptance above 85% in the wavelength range of 0.3-15 µm was realized using our method. The effect of scanning pitch between adjacent rows on large-scale black silicon was also discussed. Our method realized the ultrahigh absorptance of large-scale black silicon fabricated in air from visible to mid-infrared, which is of significance in the field of optoelectronic devices.

Dual-Scale Textured Broadband Si-Based Light Absorber.

Various antireflective structures and methods are proposed to solve the optical loss of Si-based absorber devices. Dual-scale structures have received more concern from researchers in recent years. In this study, the finite difference time domain (FDTD) method is employed to investigate deeply the dependence of optical response on the geometric shape and size of structures. The micron cone shows lower reflectivity than other micron structures. Additionally, the lowest reflectivity region moves with the increasing height size of the cone structure. We proposed creatively a nanoripple-cone structure that maintains low reflectivity properties under varying incident angles whether in the visible region or the near-infrared region. Furthermore, the lower reflectivity is obtained with increasing micron cone and decreasing nanoripple. Finally, the dual-scale nanoripple-cone is fabricated directly and cost-effectively by a femtosecond laser instead of a two-step texture-on-texture way. The measured result shows that the high absorption above 98% extends to the mid-infrared region. This study provides directions for the fabrication of wideband Si-based absorber devices to reduce reflectivity, which exhibits a wide application potential and promotes the evolution of multi-laser processing.

Dual Laser Beam Asynchronous Dicing of 4H-SiC Wafer.

SiC wafers, due to their hardness and brittleness, suffer from a low feed rate and a high failure rate during the dicing process. In this study, a novel dual laser beam asynchronous dicing method (DBAD) is proposed to improve the cutting quality of SiC wafers, where a pulsed laser is firstly used to introduce several layers of micro-cracks inside the wafer, along the designed dicing line, then a continuous wave (CW) laser is used to generate thermal stress around cracks, and, finally, the wafer is separated. A finite-element (FE) model was applied to analyze the behavior of CW laser heating and the evolution of the thermal stress field. Through experiments, SiC samples, with a thickness of 200 µm, were cut and analyzed, and the effect of the changing of continuous laser power on the DBAD system was also studied. According to the simulation and experiment results, the effectiveness of the DBAD method is certified. There is no more edge breakage because of the absence of the mechanical breaking process compared with traditional stealth dicing. The novel method can be adapted to the cutting of hard-brittle materials. Specifically for materials thinner than 200 µm, the breaking process in the traditional SiC dicing process can be omitted. It is indicated that the dual laser beam asynchronous dicing method has a great engineering potential for future SiC wafer dicing applications.