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A system consisting of a plano-convex mirror and reflecting surfaces of Vertical Cavity Surface-Emitting Laser (VCSEL) Strip Array of Diode Lasers has been calculated and proved to have a self-reproducing ray sink in it. The initial positions and slopes of two representative groups of light rays are set, and the position and slope of each light ray at each Distributed Bragg Reflector (DBR) of Diode lasers are obtained by computation. The system is a folded resonator, every VCSEL is connected by the axis of the resonator, and this axis is formed by linking the correspondent reflective points on the inner spherical surface of the mirror and the reflective points on the Bragg mirrors. One approach could be to fabricate the array directly on a plane of a GaAs (or Si) plano-convex mirror. The resonator can contain many VCSELs, and therefore can afford a high quality laser beam and high-power output.

Combining BiOCl with TiO2 nanomaterials is beneficial to enhance the photocatalytic activity and optoelectronic activity. In this paper, BiOCl nanosheet–TiO2 nanotube array composites were synthesized to enhance the photocatalytic degradation performance for methyl orange (MO) of TiO2 under ultraviolet light irradiation. BiOCl nanosheets were deposited on TiO2 nanotube arrays by the straightforward impregnation method. X-ray diffraction, scanning electron microscopy, energy dispersive x-ray spectroscopy, transmission electron microscopy, x-ray photoelectron spectroscopy, and photocurrent (i–t) were used to evaluate the composites of BiOCl nanosheets–TiO2 nanotube arrays. The results showed that the tetragonal BiOCl nanosheets clustered together on the surface of the TiO2 nanotubes and grew along the (110) crystal plane. The composites outperformed pure TiO2 regarding outstanding structure and overall photocatalytic performance, and the MO photocatalytic degradation rate was 98.5%. For the 30-BiOCl–TiO2, its photocurrent intensity (58 µA) was 4.5 higher than TiO2 (13 µA). The degradation rate of 87% can still be reached after three cycles.

Filamin B (FLNB) plays an important role in skeletal development. Mutations in FLNB can lead to skeletal malformation such as an abnormal number of ossification centers, indicating that the skeletal segmentation in the embryonic period may be interfered with. We established a mouse model with the pathogenic point mutation FLNB NM_001081427.1: c.4756G > A (p.Gly1586Arg) using CRISPR-Cas9 technology. Micro-CT, HE staining and whole skeletal preparation were performed to examine the skeletal malformation. In situ hybridization of embryos was performed to examine the transcription of HOX genes during embryonic development. The expression of FLNB was downregulated in FLNBG1586R/G1586R and FLNBWT/G1586R mice, compared to FLNBWT/WT mice. Fusions in tarsal bones were found in FLNBG1586R/G1586R and FLNBWT/G1586R mice, indicating that the skeletal segmentation was interfered with. In the embryo of FLNBG1586R/G1586R mice (E12.5), the transcription levels of HOXD10 and HOXB2 were downregulated in the carpal region and cervical spine region, respectively. This study indicated that the loss-of-function mutation G1586R in FLNB may lead to abnormal skeletal segmentation, and the mechanism was possibly associated with the downregulation of HOX gene transcription during the embryonic period.

ABSTRACTThis paper focuses on research e-infrastructures in the open science era. We analyze some of the challenges and opportunities of cloud-based science and introduce an example of a national solution in the China Science and Technology Cloud (CSTCloud). We selected three CSTCloud use cases in deploying open science modules, including scalable engineering in astronomical data management, integrated Earth-science resources for SDG-13 decision making, and the coupling of citizen science and artificial intelligence (AI) techniques in biodiversity. We conclude with a forecast on the future development of research e-infrastructures and introduce the idea of the Global Open Science Cloud (GOSC). We hope this analysis can provide some insights into the future development of research e-infrastructures in support of open science.

Long-distance drifting of seaweeds driven by ocean currents is an ideal model for exploring population-level genetic connectivity and phylogeographic structure. In the Indo-Pacific convergence region, we integrated phylogeographic and ocean current data and Lagrangian particle simulations to explore how the ocean currents contributed to the biogeographical patterns and population genetic connectivity of Sargassum polycystum. The oceanographic transport and direction of gene flow was in line with contemporary ocean currents. The S. polycystum geographical dispersal from glacial refugia homogenized the footprint of genetic divergence. The multidisciplinary intersection provides insights into the evolutionary history and biogeographic conservation of tropical seaweeds in the Indo-Pacific convergence region.

This paper presents an in-depth study of the variable reference process to improve the organization and properties of selective laser melting TC4 specimens. A relationship equation between body energy density and stratification is proposed. This study aimed to look into how layer and volume energy density affect the surface, tensile characteristics, and microstructure of specimens. The test findings demonstrated that specimen densities rise as the power index falls, with the most excellent density reaching 99.42%. The number of secondary α’ phases declined as the energy density of the laminae slowed down. The tensile strength of these specimens reached 1190.84 MPa, and the yield strength came at 1103.87 MPa with the same interval of variable laser power. This offers a fresh avenue for research into SLM to enhance the specimens’ overall performance.

Metal additive manufacturing (metal-AM) technology has made significant progress in the field of biomedicine in recent years. Originally, it was only used as an innovative resource for prototypes. With the development of technology, custom orthopedic implants could be produced for different patients. Titanium alloy is non-toxic and harmless in the human body. It has excellent biocompatibility and can promote the growth and regeneration of bones in its interior. Therefore, it is widely used in the medical industry. However, in the process of additive manufacturing and printing titanium alloys, there are often cases where the powder is not completely melted or the powder adheres to the product structure after printing, which introduces new biological risks. This paper summarizes the causes of powder adhesion from the perspective of the process involved in additive manufacturing, expounds the influence of different processes on the powder adhesion of titanium alloy forming parts, introduces the mainstream methods of powder sticking removal and summarizes the application of the additive manufacturing of titanium alloy in the medical field, which provides a theoretical basis for further development of the application of titanium alloy additive manufacturing technology in the medical industry.

A cellular automata model was established to simulate grain coarsening processes pinned by second-phase particles. The influences of particle coarsening, precipitation, growth and dissolution, which contain complex changes of size and number density of the particles, on the grain coarsening kinetics were investigated by considering the following two factors: average pinning force per particle and particle number density. The simulation results showed that the average pinning force per particle was related to the particle size, but little influenced by the particle number density. The investigations about the grain boundary/particles interactions showed that the increase of number fraction of particles, which located at the grain boundary junctions, should be the reason for the increase of average pinning force per particle. Then the limiting grain size was researched and compared to the results of some other models. The results showed that the average number of particles to stagnate a grain was related to both the number density and size of particles. At last, the comparisons between the present simulation results and the other simulation and experimental results showed that the present models were efficient in simulating the grain coarsening processes pinned by second-phase particles.

Using finite element analysis software and based on the Johnson–Cook failure criterion, a 3D printing workspace model with collapse, powder sticking, and cavity defects was established under the selective laser melting (SLM) forming process. The simulation analysis of milling holes was carried out, and the relationship between cutting speed and material-removal rate on tool wear and entrance burr was derived. The hole-milling experiment was carried out to verify the dimensional accuracy and surface appearance of the hole under the two processes of SLM direct forming and re-milling after forming; the inhibition effect of re-milling after forming on collapse, powder sticking, and cavity defects in hole forming were studied, and the formation mechanism of various defects such as burrs, scratches, and hole-wall cracks in the hole-milling process was analyzed. The Kistler9129A dynamometer was used to measure the cutting forces of re-milling holes and direct milling holes, and a comparative analysis was carried out. The influence of cutting speed, hole diameter, and material-removal rate on the axial force of milling holes was explored. The experiment results were consistent with the simulation cutting model, and the model’s accuracy was verified.

This paper studies the effects of different combinations of scanning strategies between layers on the surface quality, tensile properties, and microstructure of samples in a laser beam powder bed fusion (L-PBF) formation experiment of Ti-6Al-4V titanium alloy. The purpose of this experiment was to improve the comprehensive performance of the piece by selecting the optimal combination of scanning strategies. The results show that the surface roughness of the L-PBF specimen was the lowest under the combination of the CHESS scanning strategy, reaching 14 μm. The surface hardness of the samples was generally higher with the LINE scanning strategy and the angle offset of 90°, reaching 409 HV. The overall density of the samples was higher under the combination of CHESS scanning strategies, reaching 99.88%. Among them, the CHESS&45° sample had the best comprehensive properties, with a density of 99.85%, a tensile strength of up to 1125 MPa, a yield strength of 912 MPa, and an elongation of 8.2%. The fractured form was a ductile fracture, with many dimple structures. Compared with the CHESS scanning strategy, the tensile properties of the CHESS&45° samples were improved by 12.8%. The microstructure of the L-PBF sample was mainly composed of the primary β phase and α’ martensite phase. The upper surface of the CHESS scanning strategy combination sample had a clear melt channel, and the distribution of each phase was uniform. A certain number of columnar β crystals were distributed in the longitudinal section of the sample, which was paralleled to the build direction. The columnar β crystals of CHESS&45° were relatively coarse, which enhanced the tensile properties of the sample.

To improve the precision of the nonhorizontal suspension structure and the forming quality of the overhanging surface by selective laser melting, the influence of laser power on the upper surface and the overhanging surface forming quality of 316L stainless steel at different forming angles was studied in the experiment. The influence of different scanning strategies, upper surface remelting optimization, and overhang boundary scanning optimization on the formation of overhanging structures was compared and analyzed. The forming effect of chromium–nickel alloy is better than 316L stainless steel below the limit forming angle in the overhanging structure. The better forming effect of chromium–nickel alloy can be obtained by narrowing the hatch space with the boundary optimization process. The experiment results show that the forming of the overhanging structure below the limit forming angle should adopt the chessboard scanning strategy. The smaller laser power remelting is beneficial to both the forming of the overhanging surface and the quality of upper surface forming. The minimum value of surface roughness using the 110 W power laser twice during surface remelting and boundary scanning 75° overhanging surface can reach 11.9 μm and 31.1 μm, respectively. The forming accuracy error range above the limit forming angle is controlled within 0.4 mm, and the forming quality is better. A boundary count scanning strategy was applied to this study to obtain lower overhanging surface roughness values. This research proposes a process optimization and improvement method for the nonhorizontal suspension structure formed by selective laser melting, which provides the process support for practical application.