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In order to explore the resource utilization of nitrate nitrogen in wastewater and the high-value utilization mode of excess reed resources in Baiyang Lake, this paper prepared modified reed straw(MRS) with waste reed straw(RS) as raw material. Through adsorption desorption regeneration experiments, MRS recycling application experiments and SEM, XPS, FT-IR characterization methods, the potential use of MRS in the removal of nitrate nitrogen in wastewater and its recycling was explored. The results showed that the maximum adsorption capacity of MRS for nitrate was 8.54 mg/g, and its adsorption behavior was in line with the Freundlich adsorption isotherm model. The adsorption process was more in line with the pseudo second-order adsorption kinetics model. After 9 adsorption-desorption-regeneration cycles, the adsorption performance of the adsorbent did not significantly decrease, the material adsorbing nitrate nitrogen(MRS-NO3-) used as fertilizer played a significant role in promoting plant growth, and the pH of the experimental soil did not change. In conclusion,MRS is a low-cost, efficient and harmless nitrate adsorbent. This study preliminarily realized the resource utilization of nitrate nitrogen in wastewater and the high-value utilization mode of excess reed resources in Baiyang Lake through the technical route of adsorption-desorption-regeneration-recycling.

The use of prestressing anchor active support technology in tunnel engineering is becoming morecommon.However, the support characteristics and mechanism of action have not been fully understood for shallow, large-span rocky tunnels.In order to investigate the bearing characteristics of the surrounding rock under the prestressed anchor support system, a concealed excavation station of Qingdao Metro Line 6 was used as the engineering background, and based on the similarity principle of formulating experimental materials for stratum and support structure modelling, the bearing characteristics of the anchors under the prestressed anchor and ordinary anchor support were investigated by hydraulic loading tests.The results indicate that: ① The interaction between prestressed anchors and the surrounding rock creates a load-bearing anchor solid that can effectively support most of the overlying loads.The application of prestressed anchors during the overburden loading process increased the warning load value of tunnel instability damage by 42.8% and the ultimate load value by 41.2%.② The overburden loading process involved the prestressing anchors going through the tight anchorage load holding stage and the de-anchorage unloading stage.Simultaneously, the lining underwent the strain accumulation stage, strain surge stage, and strain release stage during the overlay loading process.③ The prestressed anchor under active support has better force synergy with the rock body than an ordinary anchor, without the axial force mutation phenomenon.This allows the support performance of the anchor to be fully utilized.Additionally, the prestressed active support effectively inhibits the development of fissures and significantly improves the overall stability of the tunnel.

Vortex beams carrying orbital angular momentum (OAM) are considered to hold significant prospects in fields such as super-resolution imaging, high-capacity communications, and quantum optics. Therefore, the techniques of vortex beam generation have attracted extensive studies, in which the development of metasurfaces brings new vigor and vitality to it. However, the generation of reconfigurable vortex beams by metasurfaces at the incidence of arbitrary polarized electromagnetic (EM) waves holds challenges. In this study, an efficient and reconfigurable strategy utilizing PB phase-modulated circularly polarized waves and dynamic phase-modulated linearly polarized waves is proposed, enabling a polarization-locked fully polarization vortex beams generator. Based on this strategy, we designed and fabricated a prototype of the vortex beam generator for full polarization, which verifies the rotating Doppler effect and generates a time-varying vortex beam. All the results have been verified by simulation and measurements. In addition, the proposed strategy can be easily extended to other frequency regions and holds potential in areas such as information encryption, biosensing, and OAM multiplexing communication.

In view of the waste of reed resources in Xiong’an New Area and the difficulty in separating the adsorbent in the process of removing nitrate nitrogen from water by adsorption，the magnetic amine-crosslinked biopolymer based reed straw was prepared from waste reed straw. The preparation method of the adsorbent was optimized by comprehensively considering the effects of reagent type，reagent dosage，reaction time，reaction temperature and other conditions during the preparation process. The adsorption performance of the adsorbent on simulated wastewater was investigated and characterized by SEM，VSM，FT-IR and XPS. The results showed that the removal rate of nitrate nitrogen in simulated sewage reached 93.2% by the adsorbent prepared by adding 5 mL of epichlorohydrin，20 mL of N，N-dimethylformamide and 5 mL of trimethylamine into 2 g of reed straw powder and reacting at 80 ℃ for 30 min. The static adsorption of nitrate nitrogen conformed to the Freundlich isotherm adsorption model and the quasi-second order adsorption kinetic model. In the dynamic adsorption experiment，the maximum adsorption capacity of the adsorbent for nitrate nitrogen was 12.74 mg/g. After six cycles of regeneration，the adsorption performance of the adsorbent had not significantly decreased. The characterization results showed that magnetic groups and quaternary amine groups were successfully loaded on the surface of the material，and the adsorption mechanism of nitrate nitrogen was mainly ion exchange. In conclusion，the prepared magnetic amine-crosslinked biopolymer based reed straw had good adsorption performance for nitrate nitrogen in water，and was expected to realize the high value utilization of reed resources.

Large complex components are the core structural components of equipment in the fields of aerospace, energy, ships, etc. Such components have large sizes, complex shapes, and high processing accuracy requirements. Nowadays, robotized processing systems can overcome the shortcomings of high cost, poor flexibility of the gantry equipment, which have become a powerful tool for processing large complex components. However, the ontology performance of the existing robotized processing system still has problems such as small workspace and weak load capacity, so a hybrid mechanism that can be used as the core ontology of a large complex component processing robot is proposed in this study. The hybrid mechanism consists of a series of manipulators for processing tasks and a 6-UPS parallel mechanism. The 6-UPS parallel mechanism, driven by six drive rods, is used to support the series manipulator and regulate its position and pose on the one hand, and drive the robot to travel with the hybrid mechanism as the ontology on the other hand. The kinematics modeling and workspace solutions of the serial manipulator, 6-UPS parallel mechanism and the whole hybrid mechanism are completed in this study and it is proved that the workspace of the whole hybrid mechanism is significantly larger than that of the serial manipulator and the 6-UPS parallel mechanism. The virtual prototype of the robot is designed with the proposed hybrid mechanism as the robot ontology. By realizing the gait walking of the virtual prototype in a three-dimensional software, it is proved that the designed robot can further expand the workspace using a walking function.

Due to the complexity of the actual geotechnical environment, the backfill compaction design theory and calculation method are not reflected in the current specification. Therefore, in order to investigate the effect of the hydraulic compactor on the foundation structure during the treatment of the backfill of an independent foundation under a column, the Menard formula was modified. At the same time, relying on an independent foundation project under a column in Jinan, the dynamic model of compactor tamping backfilling soil was established. The applicability of the calculation formula is verified by simulating the single-point multiple tamping on the backfill directly above the foundation tie beam, and the influence law of two factors, the thickness of the backfill and the tamping energy, on the force of the foundation tie beam is elucidated. The results show that after reaching the optimum number of tamping, the cumulative soil settlement and the effective reinforcement depth of tamping show a stable trend, and their simulation results are in good agreement with the analytical solution, which provides a supplement to the relevant safety standards. At this critical point, the force on the tie beams peaked and showed up and down fluctuations under the subsequent ramming action. The tamping action of the compactor has a significant effect on the structural forces within the effective reinforcement range, and there is a negative correlation between the magnitude of the structural forces and the thickness of the backfill. According to the numerical calculation results to choose the best construction programme, the on-site monitoring shows that under 42 KJ tamping energy and 1.5 m single backfilling thickness, the tie beam reinforcement stress reaches 18.5~55.5% of the specification warning value, which meets the safety standard. The research results of this paper can provide important guidance for the hydraulic tamping treatment of an independent foundation backfill project. [ABSTRACT FROM AUTHOR]

Platelet activation is closely related to thrombosis. Aspirin eugenol ester (AEE) is a novel medicinal compound synthesized by esterifying aspirin with eugenol using the pro-drug principle. Pharmacological and pharmacodynamic experiments showed that AEE has excellent anti-inflammatory, antioxidant, and inhibitory platelet activation effects, preventing thrombosis. However, the regulatory network and action target of AEE in inhibiting platelet activation remain unknown. This study aimed to investigate the effects of AEE on platelets of thrombosed rats to reveal its regulatory mechanism via a multi-omics approach. The platelet proteomic results showed that 348 DEPs were identified in the AEE group compared with the model group, of which 87 were up- and 261 down-regulated. The pathways in this result were different from previous results, including mTOR signaling and ADP signaling at P2Y purinoceptor 12. The metabolomics of heart and abdominal aortic tissue results showed that the differential metabolites were mainly involved in steroid biosynthesis, the citric acid cycle, phenylalanine metabolism, phenylalanine, tyrosine, and tryptophan biosynthesis, and glutathione metabolism. Molecular docking results showed that AEE had a better binding force to both the COX-1 and P2Y12 protein. AEE could effectively inhibit platelet activation by inhibiting COX-1 protein and P2Y12 protein activity, thereby inhibiting platelet aggregation. Therefore, AEE can have a positive effect on inhibiting platelet activation. [ABSTRACT FROM AUTHOR]

Petal abscission affects the growth, development, and economic value of plants, but the mechanism of ethylene-ROS-induced petal abscission is not clear. Therefore, we treated roses with different treatments (MOCK, ETH, STS, and ETH + STS), and phenotypic characteristics of petal abscission, changed ratio of fresh weight, morphology of cells in AZ and the expression of RhSUC2 were analyzed. On this basis, we measured reactive oxygen species (ROS) content in petals and AZ cells of roses, and analyzed the expression levels of some genes related to ROS production and ROS scavenging. Ethylene promoted the petal abscission of rose through decreasing the fresh weight of the flower, promoting the stacking and stratification of AZ cells, and repressing the expression of RhSUC2. During this process, ethylene induced the ROS accumulation of AZ cells and petals mainly through increasing the expressions of some genes (RhRHS17, RhIDH1, RhIDH-III, RhERS, RhPBL32, RhFRS5, RhRAC5, RhRBOHD, RhRBOHC, and RhPLATZ9) related to ROS production and repressing those genes (RhCCR4, RhUBC30, RhSOD1, RhAPX6.1, and RhCATA) related to ROS scavenging. In summary, ROS and related regulatory factors involved in ethylene induced petal abscission in roses. [ABSTRACT FROM AUTHOR]

In order to solve the complicated control of dissolved oxygen (DO) for partial nitrification in bioreactors treating high ${\rm NH}_4^ + -{\rm N}$ NH 4 + − N wastewater, a large height-diameter ratio anammox pre-reactor system was developed. And in this reactor, ${\rm NO}_2^- -{\rm N}$ NO 2 − − N accumulation rate can reach 85.76% by alternate feeding with high ${\rm NH}_4^ + -{\rm N}$ NH 4 + − N wastewater (150 mg ${\rm NH}_4^ + -{\rm N/L}$ NH 4 + − N / L ) and low ${\rm NH}_4^ + -{\rm N}$ NH 4 + − N wastewater (50 mg c) with low DO (0.19 mg/L–0.62 mg/L). Based on 16S rRNA identification technology, it was found that Nitrosomonas had a significant effect on ${\rm NH}_4^ + -{\rm N}$ NH 4 + − N oxidization in this study. And when the reactor treated higher concentration wastewater (250 mg ${\rm NH}_4^ + -{\rm N/L}$ NH 4 + − N / L ), the growth rate of Nitrosomonas was higher than that of Nitrospira (nitrite-oxidizing bacteria, NOB), which was conducive to improving the ${\rm NO}_2^- -{\rm N}$ NO 2 − − N accumulation rate and realizing partial nitrification stably. It was also found that the material exchange frequency of the microbial flora during alternate feeding with different ${\rm NH}_4^ + -{\rm N}$ NH 4 + − N concentration wastewaters was higher than that during feeding with higher ${\rm NH}_4^ + -{\rm N}$ NH 4 + − N concentration wastewater (250 mg/L) by Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolism pathways analysis. This study can provide valuable insights and lay the foundation for building anammox pre-reactors. [ABSTRACT FROM AUTHOR]