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Defence Technology（防务技术） 2024年第8期38卷 58-66页

作者： Chao Deng Huihui Liu Yongping Bai Zhen Hu School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150000China Wuxi HIT New Material Research Institute co. Ltd.Wuxi 214000China Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China

Herein, the effect of fluoropolymer binders on the properties of polymer-bonded explosives(PBXs) was co.prehensively investigated. To this end, fluorinated semi-interpenetrating polymer networks(semiIPNs) were prepared using different catalyst amounts(denoted as F23-CLF-30-D). The involved curing and phase separation processes were monitored using Fourier-transform infrared spectrosco.y, differential scanning calorimetry, a haze meter and a rheometer. Curing rate co.stant and activation energy were calculated using a theoretical model and numerical method, respectively. Results revealed that owing to its co.co.tinuous micro-phase separation structure, the F23-CLF-30-D3 semi-IPN exhibited co.siderably higher tensile strength and elongation at break than pure fluororubber F2314 and the F23-CLF-30-D0 semi-IPN because the phase separation and curing rates matched in the initial stage of *** arc Brazilian test revealed that F23-CLF-30-D-based co.posites used as mock materials for PBXs exhibited excellent mechanical performance and storage stability. Thus, the matched curing and phase separation rates play a crucial role during the fabrication of high-performance semi-IPNs;these factors can be feasibly co.trolled using an appropriate catalyst amount.

关键词： Semi-interpenetrating polymer networks Fluoropolymer Curing rate Phase separation rate Polymer-bonded explosives

Multi-scale modeling for prediction of mechanical performance in brazed GH99 thin-walled structure

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Chinese Journal of Aeronautics 2024年第7期37卷 550-563页

作者： Yazhou LIU Shengpeng HU Yanyu SONG Wei FU Xiaoguo SONG Ning GUO Weimin LONG State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Shandong Institute of Shipbuilding Technology Weihai 264209China China Machinery Intelligent Equipment Innovation Research Institute(Ningbo)co. Ltd.Ningbo 315700China

Superalloy thin-walled structures are achieved mainly by brazing,but the deformation process of brazed joints is non-uniform,making it a challenging research *** paper reco.ds a thorough investigation of the effect of brazing parameters on the microstructure of joints and its mechanical properties,which mainly inquires into the deformation and fracture mechanisms in the shearing process of GH99/BNi-5a/GH99 *** macrosco.ic-microsco.ic deformation mechanism of the brazing interface during shearing was studied by Crystal Plasticity(CP)and Molecular Dynamics(MD)on the basis of the optimal brazing *** experimental results show that the brazing interface is mainly formed by(Ni,Cr,co.(s,s)and possesses a shear strength of approximately 546 *** shearing fracture of the brazed joint occurs along the brazing seam,displaying the characteristics of intergranular *** simulations show that dislocations disassociate and transform into fine twinning with increased *** simulated the shear deformation process of the brazed *** multiscale simulation results are co.sistent with the experimental *** mechanical properties of thin-walled materials for brazing are predicted using MD and CP methods.

关键词： Multi-scale modeling Brazing Shear mechanisms Crystal plasticity GH99 superalloy

Full waveform inversion based on hybrid gradient

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Petroleum Science 2024年第3期21卷 1660-1670页

作者： Chuang Xie Zhi-Liang Qin Jian-Hua Wang Peng Song Heng-Guang Shen Sheng-Qi Yu Ben-Jun Ma Xue-Qin Liu Qingdao Innovation and Development Base Harbin Engineering UniversityQingdao266000ShandongChina Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao266000ShandongChina CNOOC Research Institute co. Ltd.Beijing100028China co.lege of Marine Geoscience Ocean University of ChinaQingdao266100ShandongChina Weihai Sunfull Geophysical Exploration Equipment co. Ltd.Weihai264209ShandongChina

The low-wavenumber co.ponents in the gradient of full waveform inversion(FWI)play a vital role in the stability of the ***,when FWI is implemented in some high frequencies and current models are not far away from the real velocity model,an excessive number of low-wavenumber co.ponents in the gradient will also reduce the co.vergence rate and inversion *** solve this problem,this paper firstly derives a formula of scattering angle weighted gradient in FWI,then proposes a hybrid *** hybrid gradient co.bines the co.ventional gradient of FWI with the scattering angle weighted gradient in each inversion frequency band based on an empirical formula derived *** weighted hybrid mode,we can retain some low-wavenumber co.ponents in the initial lowfrequency inversion to ensure the stability of the inversion,and use more high-wavenumber co.ponents in the high-frequency inversion to improve the co.vergence *** results of synthetic data experiment demonstrate that co.pared to the co.ventional FWI,the FWI based on the proposed hybrid gradient can effectively reduce the low-wavenumber co.ponents in the gradient under the premise of ensuring inversion *** also greatly enhances the co.vergence rate and inversion accuracy,especially in the deep part of the *** the field marine seismic data experiment also illustrates that the FWI based on hybrid gradient(HGFWI)has good stability and adaptability.

关键词： Full waveform inversion Hybrid gradient Scattering angle weighted Low-wavenumber co.ponent

The short and long-term effect of polystyrene nanoplastics on nitrifying sludge at high nitrite co.centrations

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Journal of Environmental Sciences 2024年第1期135卷 222-231页

作者： Xiaolong Wang Jialu Huang Zhiqiang Qi Ruiqin Kang Chao Du Da Li School of Chemical and Environmental Engineering Anyang Institute of TechnologyAnyang 455000China Henan Licheng Environmental Technology co. Ltd.Anyang 455000China State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China

The effect of nanoplastics(NPs)on nitrite oxidation bacteria(NOB)co.munity in treating high-strength wastewater remains unclear,which seriously affects the stability of nitrogen removal *** this study,highly active nitrifying sludge was enriched and exposed to 50nm polystyrene NPs(PS-NPs)for short-term(1,100,500,and 1000 mg/L,1.5 hr)and long-term(1,10,100 mg/L,40 days)at high nitrite *** co.trast to previous studies,our results showed that the exposures to PS-NPs had little effect on nitrifying *** long-term exposure,the protein/polysaccharide ratios in extracellular polymeric substances(EPS)were positively co.related with PS-NPs co.centrations(0.78–0.99).The produced reactive oxygen species(ROS)were gradually removed,and PS-NPs higher than 10 mg/L caused damage to membrane ***-term exposure for 40 days increased the co.munity diversity and caused significant differences between the co.trol and exposed *** co.trol group were dominated by Nitrobacter and Exiguobacterium,while the exposure group was dominated by Bacillus,Myco.acterium,and Nitrospira.A noticeable shift in the NOB co.munity from Nitrobacter(26.5%to 3.4%)to Nitrospira(1.61%to 14.27%)was observed.A KEGG analysis indicated a decrease in cell growth and death,cell motility and energy *** appeared that NOB co.ld adapt to PS-NPs stress through enhanced secretion and removal of oxidative ***,this study provided new insights into the response mechanism of NOB to PS-NPs exposure.

关键词： Nanoplastics Nitrifying activity Extracellular polymeric substance(EPS) Exposure co.munity analysis

Facile fabrication of graphene/g-C_(3)N_(4) for electromagnetic wave absorption

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Nano Research 2024年第3期17卷 1687-1698页

作者： Qiang Su Yunfei He Dongdong Liu Daguang Li Long Xia Xiaoxiao Huang Bo Zhong School of Materials Science and Engineering Harbin Institute of Technology WeihaiWeihai 264209China Weihai Yunshan Technology co. Ltd.Weihai 264200China State Key Laboratory on Integrated Optoelectronics College of Electronic Science&EngineeringJilin UniversityChangchun 130012China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

With the development of the miniaturization of electronic equipment and lightweight weapon equipment,there are new requirements for electromagnetic wave absorption material(EMWAM).EMWAM has outstanding electromagnetic wave absorption properties and lightweight characteristics beco.e an important direction of *** this study,graphene/g-C_(3)N_(4)(GGCN)EMWAM was first synthesized in situ by simple heat treatment,in which the g-C_(3)N_(4) had a porous structure and dispersed on the surface of *** impedance matching of the GGCN was well adjusted by decreasing the dielectric co.stant and attenuation co.stant due to the g-C_(3)N_(4) semico.ductor property and the graphite-like *** EMW loss mechanism of GGCN was also analyzed by simulating GGCN’s electric field mode distribution and resistance loss power *** analysis result shows that the distribution of g-C_(3)N_(4) among GGCN sheets can produce more polarization effects and relaxation effects by increasing the lamellar ***,the polarization loss of GGCN co.ld be increased successfully by porous g-C_(3)N_(4).Ultimately,the EMW absorption property of GGCN is optimized significantly,and GGCN exhibits excellent EMW absorption *** the thickness is 2 mm,the effective absorption bandwidth(EAB)can reach 4.6 GHz,and when the thickness is 4.5 mm,the minimum reflection loss(RLmin)at 4.56 GHz can reach-34.69 ***,the practical application of EMWAM was studied by radar cross-section(RCS)simulation,showing that GGCN has a good application prospect.

关键词： graphene/g-C_(3)N_(4) impedance matching simulation analysis dielectric loss excellent electromagnetic wave absorption

Analysis and Characterization of the GABA Transaminase and Succinate Semialdehyde Dehydrogenase Genes in the Microalga Isochrysis zhanjiangensis in Response to Abiotic Stresses

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Journal of Ocean University of China 2024年第3期23卷 775-785页

作者： TIAN Jiaojiao ZHANG Lin LU Xinyue YE Lingzhi WU Yuanyuan CHEN Deshui CAO Jiayi JIANG Jiaxin XU Jilin YAN Xiaojun Key Laboratory of Marine biotechnology of Zhejiang Province School of Marine SciencesNingbo UniversityNingbo 315211China Key Laboratory of Aquacultural biotechnology Ministry of Education Ningbo UniversityNingbo 315211China Laizhou Bay Marine Technology co. Ltd.Yantai 261400China Fujian Dalai Seed Science and Technology co. Ltd.Ningde 352101China

Gamma-aminobutyric acid(GABA),widely existing in different organisms,is rapidly accumulated in plants in response to environmental *** main biosynthesis and degradation pathways of GABA co.stitute the GABA shunt,which is tied to the tricarboxylic acid(TCA)*** transaminase(GABA-T)and succinate semialdehyde dehydrogenase(SSADH)are two essential enzymes for the GABA degradation *** there are abundant studies on GABA shunt in higher plants at the physiological and genetic levels,research on its role in microalgae remains *** study aimed at exploring the function of GABA-T and SSADH genes in Isochrysis zhanjiangensis,an important diet microalga,under different *** cloned two GABA-T genes,IzGABA-T1 and IzGABA-T2,and one SSADH gene IzSSADH from Isochrysis zhanjiangensis and co.ducted heterologous expression *** results showed that the overexpression of IzGABA-T1 or IzGABA-T2 enhanced the survival rates of yeast transformants under heat or NaCl stress,while the overexpression of IzSSADH improved yeast tolerance to NaCl stress but had no obvious effect on heat ***,the results of quantitative real-time polymerase chain reaction(qPCR)showed that IzGABA-T1 transcription increased in the HT(salinity 25,35℃)and LS(salinity 15,25℃)*** 24 h,the IzGABA-T2 transcriptions increased in the HT,LS,and HS(salinity 35,25℃)groups,but their transcription levels decreased in all groups at 48 *** transcription increased in the LS *** results suggest that IzGABA-T1,IzGABA-T2,and IzSSADH are associated with temperature and salinity stresses and possess a certain preference for different stresses.

关键词： abiotic stress GABA heterologous expression Isochrysis zhanjiangensis transcription

Optimal Energy Efficiency Based High-speed Flying co.trol Method for Hydraulic Quadruped Robot

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Journal of Bionic Engineering 2024年第3期21卷 1156-1173页

作者： Qingjun Yang Zhenyang Zhang Rui Zhu Dianxin Wang School of Mechatronics Engineering Harbin Institute of TechnologyHarbin150000China Nanjing Chenguang Group co.Ltd Nanjing210006China

Herein,a co.trol method based on the optimal energy efficiency of a hydraulic quadruped robot was proposed,which not only realizes the optimal energy efficiency of flying trot gait but also ensures the stability of high-speed ***,the energy co.sumption per unit distance was adopted as the energy efficiency evaluation index based on the co.stant pressure oil supply characteristics of the hydraulic system,and the global optimization algorithm was adopted to solve the optimal ***,the gait parameters that affect the energy efficiency of quadruped were analyzed and the mapping relationship between each parameter and energy efficiency was captured,so as to select the optimum co.bination of energy efficiency parameters,which is significant to improve endurance ***,to ensure the stability of the high-speed flying trot gait motion of the hydraulic quadruped robot,the active co.pliance co.trol strategy was ***,the proposed method was successfully verified by simulations and *** experimental results reveal that the flying trot gait of the hydraulic quadruped robot can be stably co.trolled at a speed of 2.2 m/s.

关键词： Hydraulic quadruped robot Flying trot Energy efficiency Active co.pliance co.trol

Molecular mechanism of exopolysaccharide biosynthesis regulated by wze and wzd genes on the immunomodulatory effects of probiotic Lacticaseibacillus paracasei S-NB

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Food Science and Human Wellness 2024年

作者： Luyao Xiao Qian Yang Changliang Zhang Kai Ma Xiaogan Zhao Xin Rui Wei Li Jiangsu Biodep biotechnology co.， Ltd. Jiangsu New-Bio biotechnology co.， Ltd. Sanya Institute of Nanjing Agricultural University， co.lege of Food Science and Technology， Nanjing Agricultural University

The surface macromolecules of probiotic bacteria play crucial roles in modulating immune responses in the host. Exopolysaccharide (EPS) from lactic acid bacteria (LAB) have been widely reported to exhibit immunomodulatory activity. In this study， the EPS biosynthesis gene cluster of Lacticaseibacillus paracasei S-NB was analyzed and a deletion mutant S-NB△7576 (two genes S-NB＿2175/wze and S-NB＿2176/wzd were responsible for the chain length determination and export of EPS) was successfully co.structed， resulting a 40.02% decrease in the production of EPS. The deletion of wze and wzd had little effect on the monosaccharide co.position and major groups of the two EPS fractions (BEPS1 and BEPS2). Both BEPS1 and BEPS2 co.ld inhibit the transcriptional level of tumor necrosis factor-α (TNF-α)， interleukin-1β (IL-1β)， inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (co.-2) mRNA in RAW 264.7 cells induced by lipopolysaccharide (LPS)， and enhance host immune tolerance via suppressing NF-κB and MAPK signaling. Notably， the S-NB△7576 mutant supplied with the BEPS1/BEPS2 exhibited more significant inhibition of cytokines production and the phosphorylation of p65 and c-Jun N-terminal kinase (JNK) in LPS-stimulated cells co.pared with the S-NB△7576 mutant alone. Our study provided the immunomodulatory effect of BEPS1 and BEPS2 from L. paracasei S-NB， in which the wze and wzd genes associated with EPS biosynthesis may play an important role.

关键词：

Privacy-Preserving Federated Deep Learning Diagnostic Method for Multi-Stage Diseases

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co.puter Modeling in Engineering & Sciences 2024年第6期139卷 3085-3099页

作者： Jinbo Yang Hai Huang Lailai Yin Jiaxing Qu Wanjuan Xie School of co.puter Science and Technology Harbin University of Science and TechnologyHarbin150080China Shanghai Futures Information Technology co. Ltd.Shanghai201201China Heilongjiang Province Cyberspace Research Center Harbin150001China Information Network Engineering and Research Center South China University of TechnologyGuangzhou510641China

Diagnosing multi-stage diseases typically requires doctors to co.sider multiple data sources,including clinical symptoms,physical signs,biochemical test results,imaging findings,pathological examination data,and even genetic *** applying machine learning modeling to predict and diagnose multi-stage diseases,several challenges need to be ***,the model needs to handle multimodal data,as the data used by doctors for diagnosis includes image data,natural language data,and structured ***,privacy of patients’data needs to be protected,as these data co.tain the most sensitive and private ***,co.sidering the practicality of the model,the co.putational requirements should not be too *** address these challenges,this paper proposes a privacy-preserving federated deep learning diagnostic method for multi-stage *** method improves the forward and backward propagation processes of deep neural network modeling algorithms and introduces a homomorphic encryption step to design a federated modeling algorithm without the need for an *** also utilizes dedicated integrated circuits to implement the hardware Paillier algorithm,providing accelerated support for homomorphic encryption in ***,this paper designs and co.ducts experiments to evaluate the proposed *** experimental results show that in privacy-preserving federated deep learning diagnostic modeling,the method in this paper achieves the same modeling performance as ordinary modeling without privacy protection,and has higher modeling speed co.pared to similar algorithms.

关键词： Vertical federation homomorphic encryption deep neural network intelligent diagnosis machine learning and big data

Analysis on the turning point of dynamic in-plane co.pressive strength for a plain weave co.posite

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Defence Technology（防务技术） 2024年第2期32卷 485-495页

作者： Xiaoyu Wang Zhixing Li Licheng Guo Zhenxin Wang Jiuzhou Zhao Department of Astronautic Science and Mechanics Harbin Institute of TechnologyHarbin150001China AECC co.mercial Aircraft Engine co LTDShanghai201108China

Experimental investigations on dynamic in-plane co.pressive behavior of a plain weave co.posite were performed using the split Hopkinson pressure bar. A quantitative criterion for calculating the co.stant strain rate of co.posites was established. Then the upper limit of strain rate, restricted by stress equilibrium and co.stant loading rate, was rationally estimated and co.firmed by tests. Within the achievable range of 0.001/s-895/s, it was found that the strength increased first and subsequently decreased as the strain rate increased. This feature was also reflected by the turning point(579/s) of the bilinear model for strength prediction. The transition in failure mechanism, from local opening damage to co.pletely splitting destruction, was mainly responsible for such strain rate effects. And three major failure modes were summarized under microsco.ic observations: fiber fracture, inter-fiber fracture, and interface delamination. Finally, by introducing a nonlinear damage variable, a simplified ZWT model was developed to characterize the dynamic mechanical response. Excellent agreement was shown between the experimental and simulated results.

关键词： Plain weave co.posite Dynamic strength Quantitative criterion Turning point Failure mechanism