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Axial emission characteristics of an ionic liquid electrospray thruster with a circular emitter

Chinese Journal of Aeronautics 2025年第1期38卷 297-305页

作者： Cheng YANG Jiawei LUO Xiangbei WU Yan SHEN School of Aeronautics and Astronautics Sun Yat-sen UniversityShenzhen 518107China Shenzhen Key Laboratory of Intelligent Microsatellite Constellation Shenzhen 518107China

Ionic Liquid Electrospray Thrusters(ILETs)are well suited for micro-nano satellite applications due to their small size,low power consumption,and high specific ***,the limited thrust of a single-emitter ILET restricts its use in space *** optimize the performance of ILETs and make them suitable for a wider range of space missions,we designed a Circular-emitter ILET(CILET)to convert a one-dimensional(point)emission into a twodimensional(line)*** CILET can self-organize multiple Taylor cones *** cones were photographed and the axial emission currents were measured under different voltage and pressure difference conditions with a CILET experimental *** emission can be divided into two stable states and one unstable state based on the flow and current *** current in Stable state Ⅰ increases non-linearly with the voltage,while that in Stable state Ⅱ is nearly linear with respect to the *** number of cones increases with the voltage in stable states,while the cones become short and crowded under high-voltage *** variation law of the number of cones can be explained with the self-organization *** variation in the current exhibits a good correlation with the number of *** study demonstrates the feasibility of circular emitters and experimentally indicates that the emission current is improved by approximately two orders of magnitude compared to that of a single capillary.

关键词： Electrospray Ionic liquid thruster Self-organize Emitter Taylor cone

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Sustainable Construction Material: development and Evaluation of a Low-Carbon, Industrial Solid Waste-Based Cementitious Material

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JOUrNAL OF SUSTAINABLE METALLUrGY 2025年第1期11卷 670-681页

作者： Zhao, Lin Wu, dongxu Hu, Wentao Zhang, Zhengyang Yang, Feihua Wang, Zhaojia Univ Sci & Technol Beijing Key Lab Minist Educ Efficient Min & Safety Met Min Beijing 100083 Peoples R China State Key Lab Solid Waste Reuse Bldg Mat Beijing 100041 Peoples R China Tohoku Univ Sch Environm Studies Sendai 9808579 Japan

china is a significant global producer of cement and a major contributor to carbon dioxide emissions within the building materials industry. However, in the context of the prevailing climate change challenges, the cement industry has prioritized energy conservation and carbon reduction as its primary objectives. Solid waste cementing material can be used as an alternative to reduce the emissions and heat generated in the cement industry, thus contributing to the collaborative treatment of solid waste and environmental control. This paper introduces the all-solid waste material as a potential replacement for cement. This material only requires grinding without sintering, its raw materials are all-industrial solid waste, and its production process does not emit any toxic and harmful gases, thus contributing to carbon emission reduction. This material also shows compressive properties and its solidification performance is better than that of standard cement and metals (including lead, cadmium, arsenic, and chromium) and satisfies the drinking water standard (GB 5749-2022). Using the carbon emission accounting method, this study highlights the low-carbon and energy saving properties of the all-solid waste material. This material is also environmentally friendly given its low energy consumption and CO2 emissions, thus providing an avenue for further research on cement alternatives.

关键词： Solid waste material Cement Heavy metal element Carbon emission

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deformation mechanism and support technology of deep asymmetrical soft rock roadway

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PHYSICS OF FLUIdS 2025年第3期37卷

作者： Liu, Shi-Qi Wang, Huan-Ling Lu, Jian Chi, Ming-Bo Hohai Univ Res Inst Geotech Engn Nanjing 210098 Peoples R China Taiyuan Univ Technol Coll Min Technol Taiyuan 030024 Peoples R China China Acad Safety Sci & Technol Beijing 100012 Peoples R China

The support technology for roadway rock has always posed significant challenges in mining and tunnel engineering. This is particularly true for deep asymmetrical soft rock roadway, for which no effective and mature reference technology currently exists. This paper provides a comprehensive analysis of the deformation mechanism and support technology for deep soft rock roadway at the Qingyun mine. Based on field investigation and theoretical analysis, we summarize the deformation mechanism and its influencing factors. Numerical simulation results of excavation indicate that the improved support scheme effectively controls roadway deformation, with 68.0 mm for the roof, 26.3 mm for the floor, and 45.12 and 44.98 mm for the two sidewalls. Moreover, the plastic zone depth is significantly reduced by 0.5 m to 2.0 m of roadway. Field monitoring data, including peephole, acoustic velocity, and bolt stress measurement, strongly support the positive impact of the improved support on surrounding rock deformation and stability. As the working face advances, the influence of mining disturbance on the roadway increases. Compared to primary support, the deformation of improved support scheme reduces by 17 to 65 mm. The outline of the loose circle under the improved support scheme is mapped, showing an overall depth reduction of 0.58 and 0.20 m compared to conditions without support and with primary support, respectively. We hope this research serves as a valuable reference for other soft rock engineering projects.

关键词： Mine roof supports

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Comparative Analysis of the Benefits of Glutathione-rich Yeast Hydrolysate and Astaxanthin on Growth Performance, Antioxidant Capacity and Lipid Metabolism in Pacific White Shrimp (Litopenaeus vannamei)

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JOUrNAL OF ANIMAL PHYSIOLOGY ANd ANIMAL NUTrITION 2025年第3期 2025 Jan 13页

作者： Chen, Jiandong Zhang, Ling Yang, Fan Yi, Jianhua Yang, Zhilong Li, Zhaowen Cheng, Tao Hu, Xiangna Tan, Beiping Cao, Aiqiao Chi, Shuyan Guangdong Ocean Univ Coll Fisheries Lab Aquat Nutr & Feed Zhanjiang Peoples R China Shenzhen Inspect & Testing Ctr Agr Prod Qual & Saf Shenzhen Peoples R China Angel Yeast Co Ltd Hubei Prov Key Lab Yeast Funct Yichang Peoples R China

Antioxidants, both glutathione (GSH) and astaxanthin (AX), possess beneficial applications in animal growth and antioxidant properties. In this study, three experimental diets with isoproteic and isolipidic were formulated, the control diet (CON), the control diet added with 0.03% Carophyll Pink (contains 10% AX), the control diet added with 0.67% glutathione-rich yeast hydrolysate (GYH, contains 5% GSH). The effects of AX and GYH on the growth performance, antioxidant capacity and lipid metabolism of Litopenaeus vannamei (0.36 +/- 0.01 g) were compared. After an 8-week feeding experiment, shrimp growth and intestinal morphology showed significantly better performance in the GYH group. Both dietary AX and GYH regulated the expression levels of genes related to lipid metabolism, increased antioxidant enzyme activities and total antioxidant capacity of shrimp and reduced haemolymph malondialdehyde and hepatopancreas reactive oxygen species production. Compared with the CON and GYH groups, dietary AX significantly increased the redness (a*) and yellowness (b*) values of cooked shrimp. Based on the evaluation of the above results, AX and GYH were comparable in terms of antioxidant performance, and AX was superior in improving the red body colour of shrimp, but GYH has more significant advantages in promoting shrimp growth and intestinal development. Therefore, supplementation with GYH or AX in diet presents specific benefits to the growth, body colour and antioxidant of L. vannamei.

关键词： astaxanthin body colour glutathione-rich yeast hydrolysate growth lipid metabolism Litopenaeus vannamei

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Effects of Feeding on Insect Larvae Treated With Pesticide on the Biological and Biochemical Characteristics of Arma chinensis

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ArCHIVES OF INSECT BIOCHEMISTrY ANd PHYSIOLOGY 2025年第2期118卷 e70042页

作者： Zheng, Hui Cai, Hailin Mo, Yunfei Guo, Xihui Wang, Wei Yang, Zhongxia Hunan Agr Univ Coll Plant Protect Hunan Prov Key Lab Biol & Control Plant Dis & Inse Changsha Peoples R China Hunan Tobacco Co Coll Plant Protect Hunan Prov Key Lab Biol & Control Plant Dis & Inse Tobacco Prod Technol CtrChangsha Branch Changsha Peoples R China

The effects of feeding on insect larvae treated with pesticide on the biological and biochemical characteristics of Arma chinensis were investigated. In the F0 generation, the developmental duration and preoviposition period were shortened, the average number of eggs laid was reduced, and the net reproductive rate and mean generation time were significantly lower in the treatment group compared to those in the control group. The average number of eggs laid by the F1 generation of A. chinensis was lower in the treatment group. The intrinsic rates of increase, finite rates of increase and net reproductive rates were significantly lower in the F1 generation in the treatment group than those in the control group. The activities of CarE and GST were significantly induced, while the activity of AChE was inhibited in the A. chinensis in the treatment group. The activities of trypsin and THL were significantly induced in the treatment group, while the activity of LPS was not significantly changed. At the population level, Enterococcaceae were cultured only from the intestines of the A. chinensis in the treatment group. At the genus level, in addition to Serratia, Yokenella and Klebsiella, which were consistent with the control group, the genus Enterococcus was also cultured in the treatment group. When controlling P. rapae in the field, pesticides should be reasonably selected, and an appropriate time should be chosen for the release of A. chinensis to reduce the impact on natural enemies and to achieve synergistic chemical and biological control.

关键词： Arma chinensis culturable bacteria detoxification and digestive enzymes growth and development synergies

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Two-temperature thermodynamic and transport properties of C4F7N-CO2-O2 mixture as an arc-extinguishing gas

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JOUrNAL OF PHYSICS d-APPLIEd PHYSICS 2025年第16期58卷 165502-165502页

作者： Wang, Guanyu Zhang, Boya Cao, Minchuan deng, Junwei Shi, Yuying Li, Bochen Li, Xingwen Murphy, Anthony B. Xi An Jiao Tong Univ State Key Lab Elect Insulat & Power Equipment Xian 710049 Shaanxi Peoples R China CSIRO Mfg POB 218 Lindfield NSW 2070 Australia

Given the significant greenhouse effect of SF6, the C4F7N-CO2-O-2 mixture has been identified as one of the most promising eco-friendly arc-extinguishing gases. Switching arcs typically exhibit pronounced non-local thermodynamic equilibrium (NLTE) phenomena in the peripheral regions and at the current zero-crossing point, thereby influencing the thermophysical properties of the plasma. To investigate the impact of NLTE conditions, the thermodynamic properties and transport coefficients of two-temperature (2-T) C4F7N-CO2-O-2 plasma were calculated under the local chemical equilibrium assumption. The results indicate that NLTE conditions significantly affect the properties of the mixture by altering its composition and particle energy, often having a more substantial impact than pressure variations. The generation of CO plays a critical role in shaping the thermodynamic and transport parameters of the plasma due to its molecular stability, particularly under non-equilibrium states. To maximise the arc-extinguishing performance of the gas, recommended oxygen mixing ratios are proposed. The results provide fundamental data for 2-T magnetohydrodynamic modelling of C4F7N gas mixtures in arc simulations.

关键词： C4F7N non-equilibrium plasma two temperature model arc thermodynamic properties transport coefficients

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Preamble slice orderly queue access scheme in cell-free dense communication systems

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digital Communications and Networks 2025年第1期11卷 126-135页

作者： Jun Sun Mengzhu Guo Jian Liu School of Telecommunications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China School of Computer and Communication Engineering University of Science and TechnologyBeijing 100083China

High reliability applications in dense access scenarios have become one of the main goals of 6G *** solve the access collision of dense Machine Type Communication(MTC)devices in cell-free communication systems,an intelligent cooperative secure access scheme based on multi-agent reinforcement learning and federated learning is proposed,that is,the Preamble Slice Orderly Queue Access(PSOQA)*** this scheme,the preamble arrangement is combined with the access *** preamble arrangement is realized by preamble slices which is from the virtual preamble *** access devices learn to queue orderly by deep reinforcement *** orderly queue weakens the random and avoids collision.A preamble slice is assigned to an orderly access queue at each access *** orderly queue is determined by interaction information among multiple *** the federated reinforcement learning framework,the PSOQA scheme is implemented to guarantee the privacy and security of ***,the access performance of PSOQA is compared with other random contention schemes in different load *** results show that PSOQA can not only improve the access success rate but also guarantee low-latency tolerant performances.

关键词： Machine type communication random access reinforcement learning Access success probability Federated learning

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H¹-norm Analysis of an Integral-Averaged L1 Method on Nonuniform Time Meshes for a Time-Fractional diffusion Problem

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JOUrNAL OF SCIENTIFIC COMPUTING 2025年第3期103卷

作者： Zheng, Zi-Yun Wang, Yuan-Ming East China Normal Univ Sch Math Sci Key Lab Math & Engn Applicat Shanghai Key Lab Pure Math & Math PracticeMinist Shanghai 200241 Peoples R China

A time-fractional diffusion problem with a Caputo time-fractional derivative of order alpha is an element of (0, 1) is considered, the solution of which is typically weakly singular at the initial time. For this problem, we give an H-1-norm analysis of the stability and convergence of an integral-averaged L1 method on nonuniform time meshes. The averaging of the L1 scheme that we use is known as the L1(+) or L1rline> scheme. A new positive definiteness result for the integral-averaged L1 fractional-derivative operator is established. It improves the previous positive definiteness results in the literature and plays an important role in the analysis of H-1-norm error of the integral-averaged L1 method. The H-1-norm stability holds for the general nonuniform time meshes, while the H-1-norm convergence is proved for the time graded meshes and the H-1-norm convergence order in time is min{3 + alpha, gamma alpha}/2 for all alpha is an element of (0, 1), where gamma >= 1 is the mesh grading parameter. Two full discretization methods using finite differences and finite elements in space are considered. The theoretical results are illustrated by numerical results.

关键词： Time-fractional diffusion problem Integral-averaged L1 method Nonuniform time meshes Positive definiteness H-1-norm stability and convergence

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Effect of Tooth Geometry on Multi-cycle Meshing Temperature of POM Worm Gears: Parametric Study via an Adaptive Iteration Algorithm

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CHINESE JOUrNAL OF MECHANICAL ENGINEErING 2025年第1期38卷 1-13页

作者： Li, Kaixing Xu, Wujiao Liu, Yonggang Qin, datong Chongqing Univ Coll Mat Sci & Engn Chongqing Key Lab Adv Mold Intelligent Mfg Chongqing 400044 Peoples R China Chongqing Univ State Key Lab Mech Transmiss Chongqing 400044 Peoples R China

Meshing temperature analyses of polymer gears reported in the literature mainly concern the effects of various material combinations and loading conditions, as their impacts could be seen in the first few meshing cycles. However, the effects of tooth geometry parameters could manifest as the meshing cycles increase. This study investigated the effects of tooth geometry parameters on the multi-cycle meshing temperature of polyoxymethylene (POM) worm gears, aiming to control the meshing temperature elevation by tuning the tooth geometry. Firstly, a finite element (FE) model capable of separately calculating the heat generation and simulating the heat propagation was established. Moreover, an adaptive iteration algorithm was proposed within the FE framework to capture the influence of the heat generation variation from cycle to cycle. This algorithm proved to be feasible and highly efficient compared with experimental results from the literature and simulated results via the full-iteration algorithm. Multi-cycle meshing temperature analyses were conducted on a series of POM worm gears with different tooth geometry parameters. The results reveal that, within the range of 14.5 degrees to 25 degrees, a pressure angle of 25 degrees is favorable for reducing the peak surface temperature and overall body temperature of POM worm gears, which influence flank wear and load-carrying capability, respectively. However, addendum modification should be weighed because it helps with load bearing but increases the risk of severe flank wear. This paper proposes an efficient iteration algorithm for multi-cycle meshing temperature analysis of polymer gears and proves the feasibility of controlling the meshing temperature elevation during multiple cycles by tuning tooth geometry.

关键词： POM worm gears Multi-cycle meshing temperature Adaptive iteration algorithm Tooth geometry parameters Parametric study

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Self-assembling chemically modified sirNA nanorings for rNAi therapy and neuroprotection in Alzheimer's disease

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Science china Chemistry 2025年第6期68卷 2552-2564页

作者： Yifan Jiang Lisha Li Xiao Fang Tao Zeng Lichao Su Yichang Liu Ying Wu Jinyu Li Peng Lyu Zhonglei Lu Chunhua Lu Huanghao Yang New Cornerstone Science Laboratory Ministry of Education Key Laboratory for Analytical Science of Food Safety and BiologyCollege of Chemistry Fuzhou University Fujian Key Laboratory of Medical Analysis Fujian Academy of Medical Sciences Department of Neurosurgery Fujian Institute of Brain Disorders and Brain Science Fujian Clinical Research Center for Neurological Diseases First Affiliated Hospital Fujian Medical University National & Local Joint Biomedical Engineering Research Center on Photodynamic Technologies College of Chemistry Fuzhou University College of Biological Science and Technology Fuzhou University School of Medicine Fuzhou University

The development of rNA interference(rNAi) therapy offers a potential solution for Alzheimer's disease(Ad). However, the brain-blood barrier(BBB) with its selective permeability and pharmacokinetic-related challenges poses restrictions on the delivery of small interfering rNA(si rNA) to the central nervous system(CNS). In this study, we demonstrate that the incorporation of 2'-fluoro(2'-F) substitutions and L-carnitine modification facilitates the self-assembly of si rNA through triple interaction, leading to the formation of nanorings, called LCSF-Nr. Based on the enhanced cellular uptake and lysosomal escape by 2'-F substitution and the transport across the BBB promoted by L-carnitine, the nanorings realized the improved braintargeted delivery of si rNA, both in zebrafish and mice models. Moreover, our findings highlight the therapeutic potential of LCSF-Nr formulation in an Ad zebrafish model through a synergistic effect of downregulating the β-site APP cleavage enzyme1(BACE1) gene and L-carnitine-mediated neuroprotection, effectively inhibiting pathological processes. Overall, these results suggest that the chemical modification-based si rNA self-assembly strategy enables trans-BBB delivery and presents a concise approach for synergistic therapy of Ad.

关键词： sirNA chemical modification self-assembly blood-brain barrier Alzheimer’s disease

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