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Current Research Progress in Magnesium Borohydride for Hydrogen Storage(A review)

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Progress in Natural Science:Materials International 2021年第6期31卷 809-820页

作者： Yujie Lv Ying Wu School of Energy Power and Machinery Engineering North China Electric Power University Advanced Materials Research Institute North China Electric Power University Central Iron & Steel Research Institute Advanced Technology & Materials Co. Ltd Jiangsu JITRI Advanced Energy & Materials Research Institute Co. Ltd

Hydrogen storage in solid-state materials is believed to be a most promising hydrogen-storage technology for high efficiency, low risk and low cost. Mg(BH)is regarded as one of most potential materials in hydrogen storage areas in view of its high hydrogen capacities(14.9 wt% and 145–147 kg cm). However, the drawbacks of Mg(BH)including high desorption temperatures(about 250°C–580°C), sluggish kinetics, and poor reversibility make it difficult to be used for onboard hydrogen storage of fuel cell vehicles. A lot of researches on improving the dehydrogenation reaction thermodynamics and kinetics have been done, mainly including: additives or catalysts doping, nanoconfining Mg(BH)in nanoporous hosts, forming reactive hydrides systems, multi-cation/anion composites or other derivatives of Mg(BH). Some favorable results have been obtained. This review provides an overview of current research progress in magnesium borohydride, including: synthesis methods, crystal structures, decomposition behaviors, as well as emphasized performance improvements for hydrogen storage.

关键词： Magnesium borohydride Hydrogen storage Borohydrides Kinetics Thermodynamics

Impact of extreme climate and train traffic loads on the performance of high-speed railway geotechnical infrastructures

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第3期24卷 189-205页

作者： Ying Wu Haoran FU Xuecheng BIAN Yunmin CHEN MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang UniversityHangzhou 310058China Department of Civil Engineering Zhejiang UniversityHangzhou 310058China

High-speed railways are very important in global transportation.However,the railway subgrade is significantly affected by the environment due to its exposure to the atmosphere.At present,global warming is the primary trend in world climate change and seriously damages railway infrastructure.Owing to the coupling effect of extreme environmental and train loads,various subgrade problems tend to arise,such as settlement,ballast fouling,and mud pumping,thus inducing frequent railway accidents and reducing travel safety.Insights into the problems triggered by extreme climate and train loads are critical to the design and long-term operation of high-speed railway subgrades.This study therefore presents a detailed survey of recent advances in typical subgrade problems through analyzing the problem formation mechanisms and influences.Traditional and emerging detection/monitoring technologies in respect of subgrade problems are discussed in detail,as well as pre-accident and post-accident maintenance methods.Finally,according to the existing challenges in long-term subgrade shakedown assessment,an outlook on open opportunities is provided for future research.

关键词： High-speed railways Subgrade performance Train loads Extreme climate

NBA:defensive distillation for backdoor removal via neural behavior alignment

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Cybersecurity 2023年第4期6卷 76-87页

作者： Zonghao ying Bin wu State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of SciencesBeijingChina School of Cyber Security University of Chinese Academy of SciencesBeijingChina

Recently,deep neural networks have been shown to be vulnerable to backdoor attacks.A backdoor is inserted into neural networks via this attack paradigm,thus compromising the integrity of the network.As soon as an attacker presents a trigger during the testing phase,the backdoor in the model is activated,allowing the network to make specific wrong predictions.It is extremely important to defend against backdoor attacks since they are very stealthy and dangerous.In this paper,we propose a novel defense mechanism,Neural Behavioral Alignment(NBA),for backdoor removal.NBA optimizes the distillation process in terms of knowledge form and distillation samples to improve defense performance according to the characteristics of backdoor defense.NBA builds high-level representations of neural behavior within networks in order to facilitate the transfer of knowledge.Additionally,NBA crafts pseudo samples to induce student models exhibit backdoor neural behavior.By aligning the backdoor neural behavior from the student network with the benign neural behavior from the teacher network,NBA enables the proactive removal of backdoors.Extensive experiments show that NBA can effectively defend against six different backdoor attacks and outperform five state-of-the-art defenses.

关键词： Deep neural network Backdoor removal Knowledge distillation

Collective radiance of giant atoms in non-Markovian regime

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Science China(Physics,Mechanics & Astronomy) 2023年第2期66卷 79-86页

作者： Qing-Yang Qiu Ying Wu Xin-You Lü School of Physics Huazhong University of Science and TechnologyWuhan 430074China

We investigate the non-Markovian dynamics of two giant artificial atoms interacting with a continuum of bosonic modes in a onedimensional(1D) waveguide.Based on the diagrammatic method,we present the exact analytical solutions,which predict the rich phenomena of collective radiance.For the certain collective states,the decay rates are found to be far beyond that predicted in the the Dicke model and standard Markovian framework,which indicates the occurrence of super-superradiance.The superadiance-to-subradiance transition could be realized by adjusting the exchange symmetry of giant atoms.Moreover,there exist multiple bound states in continuum(BICs),with photons/phonons bouncing back and forth in the cavity-like geometries formed by the coupling points.The trapped photons/phonons in the BICs can also be re-released conveniently by changing the energy level splitting of giant atoms.The mechanism relies on the joint effects of the coherent time-delayed feedback and the interference between the coupling points of giant atoms.This work fundamentally broadens the fields of giant atom collective radiance by introducing non-Markovianity.It also paves the way for a clean analytical description of the nonlinear open quantum system with more complex retardation.

关键词： collective symmetry conveniently

DLP:towards active defense against backdoor attacks with decoupled learning process

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Cybersecurity 2024年第1期7卷 122-134页

Deep learning models are well known to be susceptible to backdoor attack,where the attacker only needs to provide a tampered dataset on which the triggers are injected.Models trained on the dataset will passively implant the backdoor,and triggers on the input can mislead the models during testing.Our study shows that the model shows different learning behaviors in clean and poisoned subsets during training.Based on this observation,we propose a general training pipeline to defend against backdoor attacks actively.Benign models can be trained from the unreli-able dataset by decoupling the learning process into three stages,i.e.,supervised learning,active unlearning,and active semi-supervised fine-tuning.The effectiveness of our approach has been shown in numerous experiments across various backdoor attacks and datasets.

关键词： Deep learning Backdoor attack Active defense

The influence of lipid-extraction on theδ^(13)C of mesopelagic and demersal fish in the South China Sea:modification and application of lipid normalization models

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Acta Oceanologica Sinica 2023年第1期42卷 35-43页

作者： Linyu Wang Fuqiang Wang Zuozhi Chen Ying Wu State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai200241China Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao266237China South China Sea Fisheries Research Institute Chinese Academy of Fishery SciencesGuangzhou100141China

Mesopelagic fish,the most important daily vertically migrating community in the oceans,are characterized by high lipid content which may obscure the interpretation of stable isotopes analysis.Demersal fish,which are important consumers in the food web dominated by mesopelagic fish,also have a high lipid content.Here we collected 127 fish samples from the South China Sea and evaluated the effect of lipid contents on△δ^(13)C of mesopelagic and demersal fish.In lipid-extracted mesopelagic fish,the C/N content ratio(<5.5)shows a clear correlation withΔδ^(13)C(the offset of bulk and lipid-extractedδ^(13)C values),especially in non-migratory and semi-migratory species;these values were less correlation in demersal fish.Based on our results,we suggest that mesopelagic and demersal fish in different regions of the South China Sea should be studied separately using appropriate correction models and less fit for the traditional model.Moreover,the C/N content ratio should be used cautiously for establishing the lipid normalization model,especially for the fish in migratory mesopelagic fish and demersal fish.Our results also reveal that mesopelagic fish across nearby regions could be analyzed together.The new models described here can be applied in future studies of mesopelagic and demersal fish in the South China Sea.

关键词： mesopelagic fish demersal fish lipid normalization model C/N content ratio lipid content δ13C South China Sea

Targeting necroptosis in anticancer therapy:mechanisms and modulators

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Acta Pharmaceutica Sinica B 2020年第9期10卷 1601-1618页

作者： Ying Wu Guoqiang Dong Chunquan Sheng School of Pharmacy Second Military Medical UniversityShanghai 200433China School of Pharmaceutical Sciences Zhengzhou UniversityZhengzhou 450001China

Necroptosis,a genetically programmed form of necrotic cell death,serves as an important pathway in human diseases.As a critical cell-killing mechanism,necroptosis is associated with cancer progression,metastasis,and immunosurveillance.Targeting necroptosis pathway by small molecule modulators is emerging as an effective approach in cancer therapy,which has the advantage to bypass the apoptosis-resistance and maintain antitumor immunity.Therefore,a better understanding of the mechanism of necroptosis and necroptosis modulators is necessary to develop novel strategies for cancer therapy.This review will summarize recent progress of the mechanisms and detecting methods of necroptosis.In particular,the relationship between necroptosis and cancer therapy and medicinal chemistry of necroptosis modulators will be focused on.

关键词： Cell death Necroptosis Inducers Inhibitors Anticancer therapy

Hydrogen absorption-desorption characteristic of (Ti0.85Zr0.15)1.1Cr1-xMoxMn based alloys with C14 Laves phase

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Progress in Natural Science:Materials International 2022年第2期32卷 143-149页

作者： Youhua Yan Zhongyu Li Ying Wu Shaoxiong Zhou Jiangsu JITRI Advanced Energy & Materials Research Institute Co. Ltd. Advanced Materials Research Institute North China Electric Power University

The microstructure and hydrogen absorption-desorption characteristic of(Ti0.85Zr0.15)1.1Cr1-xMoxMn(x = 0.05,0.1,0.15,0.2 at.%) alloys were investigated.The results showed that the corresponding alloys were determined as a single phase of C14-type Laves structure.With the increase of Mo content,the maximum and reversible hydrogen absorption capacity decreased,the slope factor Hf increased.Among the studied alloys,(Ti0.85Zr0.15)1.1Cr0.95Mo0.05Mn had the best overall properties for practical application of hydrogen storage materials.The maximum and reversible hydrogen storage capacity were 1.76 wt% and 1.09 wt%,the slope factor Hfwas 0.51,and its dissociation enthalpy(ΔHd) and entropy change(ΔSd) were 23.1 kJ mol-1H2,93.8 J K-1mol-1 H2at 303 K,respectively.By studying the dissociation pressures of the synthesized metal hydrides,it was found that Mo had a special effect on the dissociation pressure of Ti-Zr-Cr-Mo-Mn alloys.Among the four alloys,(Ti0.85Zr0.15)1.1Cr0.95Mo0.05Mn alloy had the largest hydrogen absorption capacity and the fastest hydrogen desorption rate,which can meet the commercialization demand of hydrogen fuel cell hydrogen supply system.

关键词： Metal hydrides Ti–Zr–Cr–Mo–Mn based Alloys Laves phase Hydrogen storage properties

A substructure approach for analyzing pile foundation and soil vibrations due to train running over viaduct and its validation

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Railway Engineering Science 2022年第4期30卷 468-481页

作者： Ying Wu Xuecheng Bian Chong Cheng Jianqun Jiang Department of Civil Engineering MOE Key Laboratory of Soft Soils and Geoenvironmental EngineeringZhejiang UniversityAnzhong Building of Civil Engineering B406Zijingang CampusHangzhou 310058China

An efficient computational approach based on substructure methodology is proposed to analyze the viaduct-pile foundation-soil dynamic interaction under train loads.Thetrain-viaductsubsystemissolvedusingthe dynamic stiffness integration method,and its accuracy is verified by the existing analytical solution for a moving vehicle on a simply supported beam.For the pile foundation-soil subsystem,the geometric and material properties of piles and soils are assumed to be invariable along the azimuth direction.By introducing the equivalent stiffness of grouped piles,the governing equations of pile foundation-soil interaction are simplified based on Fourier decomposition method,so the three-dimensional problem is decomposedintoseveraltwo-dimensionalaxisymmetricfinite element models.The pile foundation-soil interaction model is verified by field measurements due to shaker loading at pile foundation top.In addition,these two substructures are coupled with the displacement compatibility condition at interface of pier bottom and pile foundation top.Finally,the proposed train-viaduct-pile foundation-soil interaction model was validated by field tests.The results show that the proposed model can predict vibrations of pile foundation and soil accurately,thereby providing a basis for the prediction of pile-soil foundation settlement.The frequency spectra of the vibration in Beijing-Tianjin high-speed railway demonstrated that the main frequencies of the pier top and ground surface are below 100 and 30 Hz,respectively.

关键词： Train moving load Viaduct Pile foundation Soil Vibration Substructure method