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Mechanical behaviors and energy absorption properties of Y/Cr and Ce/Cr coated open-cell nickel-based alloy foams

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Rare Metals 2018年第8期37卷 650-661页

作者： zhi-Li Hu qiu Pang Guo-Qiang Ji Gao-Hui Wu State Key Laboratory of Advanced Welding and Joining HarbinInstitute of TechnologyHarbin 150001China Hubei Key Laboratory of Advanced Technology of Automobile Components Wuhan University of TechnologyWuhan 430070China School of Mechanical and Electrical Engineering Wuhan Donghu UniversityWuhan 430212China Materials Test Department China National Analytical CenterGuangzhou 510070China

In this study, Y-and Ce-modified Cr coatings applied by pack cementation method were prepared on the surface of open-cell nickel-based alloy foam. The morphologies and microstructures of Y- and Ce-modified Cr coatings with various Y and Ce contents were investigated in detail. Then, the effects of Y and Ce addition on the mechanical properties of open-cell nickel-based alloy foams were analyzed and compared. Simultaneously, the energy absorption capacity and energy absorption efficiency of the Y- and Ce-modified Cr coated alloy foams were discussed and compared at the room and high temperatures. The results show that Cr coatings containing minor amounts of rare earth element （Y and Ce） are well adhered to the nickel-based foam struts. Especially, the microstructure of the 2 wt% Ce-modified Cr coating is denser and uniform. In addition, the compressive strength and plateau stress of Y- and Ce-modified Cr coated alloy foams firstly increase and then decrease by increasing the Y and Ce contents at room and high temperatures. The energy absorption capacity of Y/Cr and Ce/Cr coated alloy foams increases linearly with the strains increasing. The Ce/Cr coated alloy foams can absorb more energy than Y/Cr coated alloy foams in the plateau and densification regions at room temperature. Compared to those at room temperature, the Y- and Ce-modified Cr coated alloy foams show higher energy absorption efficiency when deforma- tion within 10%-30% at high temperature.

关键词： Open-cell nickel-based alloy foam Y-modified Cr coating Ce-modified Cr coating Pack cementation Mechanical properties

Spin-Modulated Oxygen Electrocatalysis

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Precision Chemistry 2023年第7期1卷 395-417页

作者： zhi Fang Wanting Zhao Tong shen Daping qiu Yucheng Lv Xinmei Hou Yanglong Hou Beijing Key Laboratory for Magnetoelectric Materials and Devices(BKL-MMD) Beijing Innovation Centre for Engineering Science and Advanced Technology(BIC-ESAT)School of Materials Science and EngineeringPeking UniversityBeijing 100871China Innovation Research Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China

The electrocatalysis reactions involving oxygen,such as oxygen evolution reaction(OER)and oxygen reduction reaction(ORR),play a critical role in energy storage/conversion applications,e.g.,fuel cells,metal-air batteries,and electrochemical water *** high kinetic energy barrier of the OER/ORR is highly associated with the spin state interconversion between singlet OH^(−)/H_(2)O and triplet O_(2),which is influenced by the spin state and magnetism of *** Review summarizes recent progress and advances in understanding spin/magnetism-related effects in oxygen electrocatalysis to develop spin *** is demonstrated that the spin states(low,intermediate,and high spin)of magnetic transition metal catalysts(TMCs)can directly affect the reaction barriers of OER/ORR by tailoring the bonding of oxygen intermediates with ***,the spin states of TMCs can build a spin-selective channel to filter the electron spins required for the single/triplet interconversion of O species during OER/*** this Review,we introduced many approaches to modulating spin state,for instance,altering the crystal field,oxidation state of active-site ions,and the morphology of ***’s more,a magnetic field can drive the spin flip of magnetic ions to achieve the spin alignment(↑↑)(i.e.,facilitating spin polarization),which will strengthen the spin selectivity for accelerating the filtration and transfer of the spins with the same direction for the generation and conversion of triplet ↑O=O↑.Importantly,the origin of magnetic field enhancement on OER/ORR are deeply discussed,which provides a great vision for the magnetism-assisted ***,the challenges and perspectives for future development of spin/magnetism catalysis are *** Review is expected to highlight the significance of spin/magnetism theory in breaking the bottleneck of electrocatalysis field and promote the development of high-efficientcy electrocatalysts for practical applications.

关键词： Oxygen electrocatalysis Magnetic transition metal catalyst Spin modulation Magnetic field Spin polarization Spin selectivity

A lithiated gel polymer electrolyte with superior interfacial performance for safe and long-life lithium metal battery

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Journal of Energy Chemistry 2021年第4期30卷 313-322页

作者： Jia-Jia Yuan Chuang-Chao Sun Li-Feng Fang You-zhi Song Yan Yan Ze-Lin qiu Yu-Jie shen Han-Ying Li Bao-Ku Zhu Key Laboratory of Macromolecular Synthesis and Functionalization(Ministry of Education) Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027ZhejiangChina Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China

Rechargeable lithium metal batteries(LMBs)have gained much attention ***,the short lifespan and safety issues restrict their commercial *** we report a novel gel polymer electrolyte(GPE)based on lithiated poly(vinyl chloride-r-acrylic acid)(PVCAALi)to realize dendritesuppressing and long-term stable lithium metal *** chains ensure the quick gelation process and high electrolyte uptake,and lithiated PAA segments enable the increase of mechanical strength,acceleration of lithium-ion transmission and improvement of interfacial *** GPE showed much higher mechanical strength compared with other free-standing GPEs in previous *** displays a superior ionic conductivity of 1.50 m S cm^(-1) and a high lithium-ion transference number of 0.59 at room ***,the lithiated GPE exhibits excellent interfacial compatibility with lithium metal *** symmetrical cells with PVCAALi GPE yield low hysteresis of 50 m V over1000 h at 1.0 m A cm^(-2).And the possible mechanism of the lithiated GPE with improved lithium-ion transfer and interfacial property was ***,both the Li4Ti5O12/Li and lithium-sulfur(Li-S)cells assembled with PVCAALi GPE show outstanding electrochemical performance,retaining high discharge capacities of 133.8 m Ah g^(-1) and 603.8 m Ah g^(-1) over 200 cycles,*** work proves excellent application potential of the highly effective and low-cost PVCAALi GPE in safe and long-life LMBs.

关键词： Lithiation Gel polymer electrolyte Lithium dendrite Safety Lithium metal battery

Automatic traceability link recovery via active learning

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Frontiers of Information Technology & Electronic Engineering 2020年第8期21卷 1217-1225页

作者： Tian-bao DU Guo-hua shen zhi-qiu HUANG Yao-shen YU De-xiang WU College of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing 210093China Key Laboratory of Safety-Critical Software Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Traceability link recovery(TLR)is an important and costly software task that requires humans establish relationships between source and target artifact sets within the same *** research has proposed to establish traceability links by machine learning ***,current machine learning approaches cannot be well applied to projects without traceability information(links),because training an effective predictive model requires humans label too many traceability *** save manpower,we propose a new TLR approach based on active learning(AL),which is called the AL-based *** evaluate the AL-based approach on seven commonly used traceability datasets and compare it with an information retrieval based approach and a state-ofthe-art machine learning *** results indicate that the AL-based approach outperforms the other two approaches in terms of F-score.

关键词： Automatic Traceability link recovery Manpower Active learning

Converting Thiophene in Simulated Coking Crude Benzene to N,N-Dimethyl-2-thiophenecarboxamide by Dimethylcarbamyl Chloride Under Mild Conditions

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Chemical Research in Chinese Universities 2019年第4期35卷 674-679页

作者： shen Xizhou SONG Hao FANG Liuya DENG Hang GAN Feng shen zhi School of Chemical Engineering & Pharmacy Wuhan Institute of Technology Wuhan 430205 P. R. China Key Laboratory for Green Chemical Process Ministry of Education Wuhan Institute of Technology Wuhan 430073 P. R. China

Since the content of thiophene in coking crude benzene is high, it is necessary to remove it from coking crude benzene for efficient utilization. In this study, an important intermediate, N,N-dimethyl-2-thiophenecarboxamide, was synthesized from thiophene and dimethylcarbamyl chloride. The influences of the dosages of dimethylcarbamyl chloride and ZnCl2 catalyst, reaction temperature and time on the removal rate were further explored based on the reaction *** structure of the target product was characterized by means of MS,NMR and 13C *** removal rate of thiophene was 98.14% after the reaction for 2 h and thiophene was almost removed after the reaction for 3 h under the optimal reaction conditions [a molar ratio of n(thiophene):n(dimethylcarbamyl chioride):w(ZnCl2)=1:12:10,300 r/min, 318 K and 101.325 kPa].The acylation of thiophene with dimethylcarbamyl chloride was approximately in accord with the first order kinetic equation at *** activation energy was 53.9850 kJ/mol and the pre-exponential factor was 1.4521×10^9 h^-1.

关键词： Coking crude benzene F-C acylation Acyl chloride Thiophene Thiophene derivative

Evaluation of underground blast-induced ground motions through nearsurface low-velocity geological layers

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第3期15卷 600-617页

作者： Yonggang Gou Xiuzhi Shi zhi Yu Xiaofeng Huo Xianyang qiu College of Civil and Transportation Engineering Hohai UniversityNanjing210098China School of Resources and Safety Engineering Central South UniversityChangsha410083China Oulu Mining School University of OuluOuluFI-90014Finland

Surface ground motion produced by underground blasts is significantly influenced by near-surface geological ***,near-surface low-propagation velocity layers were always ignored in past analyses of ground motions due to their thin *** the rising concern about surface ground motions produced by the ascendant scale and frequentness of underground excavation and mining,close attention is gradually paid to ground blast ***,systemic experiments were conducted and took seven months in an underground mine to clarify the variation of motion from underground rock to surface *** attenuation of surface ground peak particle velocities(PPVs)is compared to that in underground rock,and horizontal amplitudes are compared to vertical *** between bedrock and surface ground vibrations are analyzed to illustrate the site effect of near-surface lower-propagation velocity ***-dimensional site response analysis is employed to quantify the influence of different geological profiles on surface ground *** experimental data and site response analysis allowed the following conclusions:(1)geological site effects mainly produce decreasing dominant frequency(DF)of surface ground vibrations;(2)the site amplification effect of blast vibration needs to be characterized by peak particle displacement(PPD);(3)shear waves(S-waves)begin to dominate and surface Rayleigh waves(R-waves)develop as blast-induced ground vibrations travel upward through rock and lower-velocity layers to the *** comparison of response relative displacement to a critical value is best to assess the potential for cracking on surface structures.

关键词： Surface ground motions Underground blasts Geological site condition Amplitude attenuation Site response analysis

Development of Transgenic Glyphosate-Resistant Rice with G6 Gene Encoding 5-Enolpyruvylshikimate-3-Phosphate Synthase

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Agricultural Sciences in China 2011年第9期10卷 1307-1312页

作者： ZHAO Te LIN Chao-yang shen zhi-cheng State Key Laboratory of Rice Biology and Institute of Insect Sciences Zhejiang University Hangzhou 310028 P.R. China

Glyphosate-resistant crops have been a huge economic success for genetic engineering. The creating of new glypbosateresistant plants would increase the available choices for planting and lower the price of genetically modified crop seeds. A novel G6 gene from Pseudomonas putida that encoded 5-enolpyruvylshikimate-3-phosphate synthase （EPSPS） was previously isolated. The G6 gene was transfected into rice via Agrobacterium-mediated transformation. The transgenic rice obtained was confirmed by PCR, Southern, and Western blots. The lab experiment and field trials further confirmed that the transgenic rice can survive glyphosate spraying at a dose of 8 g L^-1. In contrast, conventional rice was killed at a weed control glyphosate spray dose of 1 g L^-1. Altogether, the present study showed that the G6 gene works well in rice in vivo for glyphosate-resistance.

关键词： transgenic rice glyphosate-resistance EPSPS

A mathematical diffusion model of carbon isotopic reversals inside ultra-tight Longmaxi shale matrixes

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Petroleum Science 2022年第5期19卷 2014-2026页

作者： Bao-Jian shen zhi-Liang He Cheng Tao Jin-Cai shen Zong-Quan Hu zhi-Ming Li Yuan-Hao Cao Wei Chen State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development SINOPECBeijing100083China Wuxi Petroleum Geology Institute SINOPEC Petroleum Exploration and Production Research InstituteWuxiJiangsu 214126China China Petroleum&Chemical Corporation Beijing100728China Chongqing Fuling Shale Gas Exploration and Development Co. Ltd.SINOPECChongqing408014China Petroleum Exploration and Production Research Institute SINOPECBeijing100083China School of Energy Soochow UniversitySuzhouJiangsu 215006China

Developing mathematical models for high Knudsen number(Kn)flow for isotopic gas fractionation in tight sedimentary rocks is still *** this study,carbon isotopic reversals(δ^(13)C_(1)>δ^(13)C_(2))were found for four Longmaxi shale samples based on gas degassing *** in shale with higher gas content exhibits larger ***,a mathematical model was developed to simulate the carbon isotopic reversals of methane and *** model is based on these hypotheses:(i)diffusion flow is dominating during gas transport process;(ii)diffusion coefficients are nonlinear depending on concentration *** model not only shows a good agreement with isotopic reversals,but also well predicts gas production rates by selecting appropriate exponents m and m^(*) of gas pressure gradient,where m is for ^(12)C and m^(*)is for ^(13)***,the(m−m^(*))value has a positive correlation with fractionation level.(m1−m1^(*))of methane are much higher than that of ***,the predicted carbon isotopic reversal magnitude(δ^(13)C_(1)−δ^(13)C_(2))exhibits a positive relationship with total gas content since gas in shale with higher gas content experiences a more extensive high Kn number diffusion *** a result,our model demonstrates an impressive agreement with the experimental carbon isotopic reversal data.

关键词： Diffusion Isotopic fractionation Carbon isotopic reversal Modeling

Robust video denoising with sparse and dense noise modelings

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Science China(Information Sciences) 2018年第1期61卷 270-272页

作者： Guiping shen zhi HAN Xi'ai CHEN Yandong TANG State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of Sciences University of Chinese Academy of Sciences

Videos can be contaminated by noise even when captured by high-quality *** video data has both spatial and temporal redundancies,low rank factorization has been ***,most denoising methods relied on a single statistical distribution to model noise,such as Gaussian distribution[1,2].Ji et al.[3]proposed a low rank matrix completion(LRMC)relying on

关键词： Robust video denoising with sparse and dense noise modelings Figure