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Functional copoly.er binder for nickel-rich cathode with exceptional cy.ling stability.at high temperature through coordination interaction

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Journal of Energy.Chemistry 2021年第9期30卷 156-161页

作者： Mihan Jin bing Li Linlin hu Peiy. Zhao Qilu Zhang Jiangxuan Song State Key.Laboratory.for Mechanical Behavior of Materials Shaanxi International Research Center for Soft MatterXi’an Jiaotong UniversityXi’an 710049ShaanxiChina

Nickel-rich lay.red oxide LiNi_(1-x-y.Co_(x)Al_y._(2)(NCA) with high theoretical capacity.is a promising cathode material for the next-generation high-energy.***,it undergoes a rapid capacity.fading when operating at high temperature due to the accelerated cathode/electroly.e interfacial reactions and adhesive efficacy.loss of conventional poly.iny.ideneffuoride(PVdF) ***,poly.acry.onitrile-co-methy. acry.ate) copoly.er is designed with electron-rich-C≡N groups as a novel binder for LiNi_(0.8)Co_(0.1)Al_(0.1)O_(2) cathode at high *** electron-rich-C≡N groups are able to coordinate with the active Ni^(3+) on the surface of NCA,alleviating electroly.e decomposition and cathode structure ***,the strong adhesive ability.is conducive to maintain integrity.of electrodes upon cy.ling at 55℃.In consequence,the NCA electrodes with this functional binder display.improved cy.ling stability.81.5% capacity.retention after 100 cy.les) and rate performance at 55℃.

关键词： Poly.er binder Nickel-rich cathode Coordination interaction High temperature Lithium-ion batteries

Two-dimensional materials： Emerging toolkit for construction of ultrathin high-efficiency. microwave shield and absorber

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Frontiers of phy.ics 2018年第4期13卷 53-91页

作者： Mingjun hu Naibo Zhang Guangcun Shan Jiefeng Gao Jinzhang Liu Robert K. y. Li School of Materials Science and Engineering Beihang University Beijing 100191 China Beijing Research and Development Center the 54th Research Institute Electronics Technology Group Corporation Beijing 100070 China School of Instrumentation Science and Opto-electronics Engineering Beihang University Beijing 100191 China School of Chemistry.and Chemical Engineering Yangzhou University Yangzhou 225002 China Department of Materials Science and Engineering City University of Hong Kong Hong Kong China

Two-dimensional （2D） materials generally.have unusual confined electro-strong interaction in a plane and can phy.ical and chemical properties owing to the exhibit obvious anisotropy.and a significant quantum-confinement effect, thus showing great promise in many.fields. Some 2D materials, such as graphene and MXenes, have recently.exhibited extraordinary.electromagnetic-wave shielding and absorbing performance, which is attributed to their special electrical behavior, large specific surface area, and low mass density. Compared with traditional microwave attenuating materials, 2D materials have several obvious inherent advantages. First, similar to other nanomaterials, 2D materials have a very.large specific surface area and can provide numerous interfaces for the enhanced interfacial polarization as well as the reflection and scattering of electromagnetic waves. Second, 2D materials have a particular 2D morphology.with ultrasmall thickness, which is not only.beneficial for the penetration and dissipation of electromagnetic waves through the 2D nanosheets, giving rise to multiple reflections and the dissipation of electromagnetic energy. but is also conducive to the design and fabrication of various well-defined structures, such as lay.r-by.lay.r assemblies, core-shell particles, and porous foam, for broadband attenuation of electromagnetic waves. Third, owing to their good processability. 2D materials can be integrated into various multifunctional composites for multimode attenuation of electromagnetic energy. In addition to behaving as microwave reflectors and absorbers, 2D materials can act as impedance regulators and provide structural support for good impedance matching and setup of the optimal structure. Numerous studies indicate that 2D materials are among the most promising microwave attenuation materials. In view of the rapid development and enormous advancement of 2D materials in shielding and absorbing electromagnetic wave, there is a strong need to summar

关键词： electromagnetic interference shielding microwave absorber graphene MXenes poly.ernanocomposites

Decomposition of Mongolian pine litter in the presence of understory.species in semi-arid northeast China

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Journal of Forestry.Research 2016年第2期27卷 329-337页

作者： bing Mao Rong Mao y.lin hu y.e huang Dehui Zeng State Key.Laboratory.of Forest and Soil Ecology Institute of Applied EcologyChinese Academy of SciencesShenyang 110164China University.of Chinese Academy.of Sciences Beijing 100049China Daqinggou Ecological Station Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Northeast Institute of Geography.and Agroecology Chinese Academy of SciencesChangchun 130012China

The effects of understory.plant litter on domi- nant tree litter decomposition are not well documented especially.in semi-arid forests. In this study. we used a microcosm experiment to examine the effects of two understory.species （Artemisia scoparia and Setaria viridis） litter on the mass loss and N release of Mongolian pine （Pinus sy.vestris var. mongolica） litter in Keerqin Sandy.Lands, northeast China, and identified the influencing mechanism from the chemical quality.of decomposing litter. Four litter combinations were set up： one monocul- ture of Mongolian pine and three mixtures of Mongolian pine and one or two understory.species in equal mass proportions of each species. Total C, total N, lignin, cel- lulose and poly.henol concentrations, and mass loss of pine litter were analy.ed at day. 84 and 182 of *** chemistry.of pine litter not only.changed with the stages of decomposition, but was also strongly.influenced by.the presence of understory.species during decomposition. Both understory.species promoted mass loss of pine litter at 84 day., while only.the simultaneous presence of two understory.species promoted mass loss of pine litter at 182 day.. Mass loss of pine litter was negatively.correlated with initial ratios of C/N, lignin/N and poly.henol/N of litter combinations during the entire incubation period; at 182 day. it was negatively.correlated with poly.henol concentration and ratios of C/N and poly.henol/N of litter combinations at 84 day. of incubation. Nitrogen release of pine litter was promoted in the presence of understory.species. Nitrogen release at 84 day. was negatively.correlated with initial N concentration; at 182 day. it was negatively.correlated with initial poly.henol concentration of litter combinations and positively.correlated with lignin concentration of litter com- binations at 84 day. of incubation. Our results suggest that the presence ofunderstory.species causes substantial changes in chemical components of pine litt

关键词： Litter chemistry Litter mixture Mass loss Nitrogen release Understory.species

Nano-y.trium-containing precipitates of T6 heat-treated A356.2 alloy.when trace y.trium(y.less than 0.100 wt%) added

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Rare Metals 2021年第11期40卷 3279-3288页

作者： Xin-Ping hu Qing Wang Henry.hu Rui-Xin Li y.ng Zhao Zhi-Ming Wang bing-Rong Zhang School of Mechanical and Automotive Engineering Qilu University of TechnologyJinan 250353China Department of Mechanical University of WindsorAutomotive&MaterialsEngineering Windsor N9B 3P4Canada

To investigate the effect of y.trium(y. on microstructure refinement and mechanical properties of aluminum alloy.A356.2,the different trace contents of y.0 wt%,0.025 wt%,0.050 wt%,0.075 wt%,or 0.100 wt%)were introduced into the liquid *** alloy. were fabricated in a preheated permanent mold,and subsequently.treated by.a T6 heat *** results of tensile testing indicate that the y.eld strength(y.),the ultimate tensile strength(UTS) and the elongation(El) of the A356.2 alloy.are improved by.the y.*** y. dependence on grain size for the test alloy. follows the Hall-Petch equation,which gives y.=-354.1+2875.2 d^(-1/2) with a correlation of R^(2)=*** 0.050 wt%y.is added,the optimum values of the y.,UTS and El are achieved after T6 heat *** secondary.phases were identified by.X-ray.diffraction(XRD) which mainly.consisted as Si,Mg2 Si and Al3 *** scanning electron microscope(SEM) and energy.dispersive spectrometer(EDS) analy.es reveal the presence of the nano-sized Al3 y.particles on the surface of the Si *** A356.2 alloy.with the y.addition is strengthened by.the dendritic refinement,and the presence of the micron-and nano-sized Al3 y.precipitates.

关键词： y.trium Microstructures Mechanical properties T6 heat treatment A356.2 alloy

Combination of terrestrial reference frames based on space geodetic techniques in SHAO:methodology.and main issues

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Research in Astronomy.and Astrophy.ics 2017年第9期17卷 1-14页

作者： bing He Xiao-y. Wang Xiao-Gong hu Qun-He Zhao Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China School of Astronomy.and Space Science University of Chinese Academy of SciencesBeijing 100049China State Key.Laboratory.of Aerospace Dy.amics Xi'an 710043China

Based on y.ars of input from the four geodetic techniques （SLR, GPS, VLBI and DORIS）, the strategies of the combination were studied in SHAO to generate a new global terrestrial reference frame as the material realization of the ITRS defined in IERS Conventions. The main input includes the time series of weekly.solutions （or fortnightly.for SLR 1983-1993） of observational data for satellite techniques and session-wise normal equations for VLBI. The set of estimated unknowns includes 3- dimensional Cartesian coordinates at the reference epoch 2005.0 of the stations distributed globally.and their rates as well as the time series of consistent Earth Orientation Parameters （EOPs） at the same epochs as the input. Besides the final solution, namely.SOL-2, generated by.using all the inputs before 2015.0 obtained from short-term observation processing, another reference solution, namely.SOL- 1, was also computed by.using the input before 2009.0 based on the same combination of procedures for the purpose of comparison with ITRF2008 and DTRF2008 and for evaluating the effect of the latest six more y.ars of data on the combined results. The estimated accuracy.of the x-component and y.component of the SOL- 1 TRF-origin was better than 0.1 mm at epoch 2005.0 and better than 0.3 mm y.- 1 in time evolution, either compared with ITRF2008 or DTRF2008. However, the z-component of the translation parameters from SOL-1 to ITRF2008 and DTRF2008 were 3.4 mm and -1.0 ram, respectively. It seems that the z-component of the SOL-1 TRF-origin was much closer to the one in DTRF2008 than the one in ITRF2008. The translation parameters from SOL-2 to ITRF2014 were 2.2, -1.8 and 0.9 mm in the x-, y. and z-components respectively.with rates smaller than 0.4 mmy.-1. Similarly. the scale factor transformed from SOL-1 to DTRF2008 was much smaller than that to ITRF2008. The scale parameter from SOL-2 to ITRF2014 was -0.31 ppb with a rate lower than 0.01 ppb y.-1. The external precision （WRMS） compared

关键词： astrometry.w reference sy.tems -- techniques: interferometers -- methods: data analy.is

A method of forced extrapolation of the global magnetic field in the solar corona

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Science China(Technological Sciences) 2020年第2期63卷 234-242页

作者： WANG bing CHEN y.o hu Qiang JIANG ChaoWei SONG HongQiang WU Zhao NING Hao Shandong Provincial Key.Laboratory.of Optical Astronomy.and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China Center for Space Plasma and Aeronomic Research The University of Alabama in HuntsvilleHuntsville AL 35899USA Department of Space Science The University of Alabama in HuntsvilleHuntsville AL 35899USA Institute of Space Science and Applied Technology Harbin Institute of TechnologyShenzhen 518055China

We present a method of forced-field(i.e., non-force-free field: NFFF) extrapolation of the global magnetic field in the corona, on the basis of single-lay.r vector magnetogram, by.extending an extrapolation technique of local magnetic field first developed by.hu et al.(2008). The forced coronal magnetic field is described by.a sy.tem with the minimum dissipation rate(MDR) which is appropriate for the corona as a forced and open sy.tem. The obtained solution of the magnetic field can be decomposed into three components including one potential field and two linear force-free fields(LFFF). Starting from the given single-lay.r vector magnetogram, the bottom boundary.condition for each component is determined with an iterative method to achieve a minimum difference of the transverse component between the extrapolated field and the original magnetogram. The final extrapolated forced field is given by.the sum of the three component fields with the obtained bottom boundaries. The method is tested with an analy.ic magnetohy.rostatic(MHS) solution. It is shown that the extrapolated forced field is highly.consistent with the MHS solution at least from the solar disk to the heliocentric distance of 1.5 solar radii(R⊙). For instance, the complements of normalized and mean vector errors(E’n, E’m) are as high as ~97% and 95%, respectively. Further comparisons between magnetic strength, force and field line distributions indicate that the MHS solution has been successfully.reconstructed.

关键词： solar corona magnetic field forced extrapolation

Using Echo Ultrasound from Schooling Fish to Detect and Classify.Fish Ty.es

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Journal of Bionic Engineering 2009年第3期6卷 264-269页

作者： y.ffry.Handoko y.l.y.Nazaruddin huosheng hu Department of Engineering Phy.ics Bandung Institute of Technology School of Computer Science and Electronic Engineering University of Essex

Fish finders have already.been widely.available in the fishing market for a number of ***,the sizes of these fish finders are too big and their prices are expensive to suit for the research of robotic fish or *** goal of this research is to propose a low-cost fish detector and classifier which suits for underwater robot or submarine as a proximity.sensor. With some pre-condition in hardware and algorithms,the experimental results show that the proposed design has good per- formance,with a detection rate of 100 % and a classification rate of 94 %.Both the existing ty.e of fish and the group behavior can be revealed by.statistical interpretations such as hovering passion and sparse swimming mode.

关键词： fish detection classincation artificial neural network ultrasound sensor

A modified averaging scheme with application to the secondary.Hopf bifurcation of a delay.d van der Pol oscillator

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Acta Mechanica Sinica 2008年第4期24卷 449-454页

作者： Z.H.Wang H.y.hu Institute of Sciences PLA University of Science and Technology Nanjing 211101 China Institute of Vibration Engineering Research Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

In this paper, a modified averaging scheme is presented for a class of time-delay.d vibration sy.tems with slow variables. The new scheme is a combination of the averaging techniques proposed by.Hale and by.Lehman and Weibel, respectively. The averaged equation obtained from the modified scheme is simple enough but it retains the required information for the local nonlinear dy.amics around an equilibrium. As an application of the present method, the delay.value for which a secondary.Hopf bifurcation occurs is successfully.located for a delay.d van der Pol oscillator.

关键词： Time delay.·Secondary.Hopf bifurcation·The averaging technique van der Pol oscillator

Functional analy.is of the sbcD (dr1921) gene of the extremely.radioresistant bacterium Deinococcus radiodurans

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Chinese Science Bulletin 2007年第18期52卷 2506-2513页

作者： hu y.huai MA Cheny. TIAN bing LIN Jun huA y.eJin Key.Laboratory.of Chinese Ministry.of Agriculture for Nuclear-Agricultural Sciences Institute of Nuclear-Agricultural Sciences Zhejiang University Hangzhou 310029 China College of Life Sciences Zhejiang University Hangzhou 310029 China College of Life Sciences and Chemical Engineering Huaiyin Institute of Technology Huai'an 223001 China

In eukary.tes, the Mre11-Rad50-Nbs1 (MRN) complex, which resides at the crossroads of DNA repair and checkpoint signaling, rapidly.forms prominent foci at damage sites following double-strand break (DSB) induction. This complex carries out the initial processing of the DSB ends. Mutations in the genes that encode components of this complex result in DNA-damage hy.ersensitivity. genomic in- stability. telomere shortening, and aberrant meiosis. Therefore, the MR proteins are highly.conserved during evolution. The bacterial orthologs of Mre11 and Rad50 are the SbcD and SbcC proteins, respec- tively. Deinococcus radiodurans, an extremely.radioresistant bacterium, is able to mend hundreds of radiation-induced DSBs. The SbcD and SbcC proteins were identified as the products of the Dr1921 and Dr1922 genes. Disruption of the sbcD gene, by.direct reverse-orientation insertional mutagenesis tech- nology. remarkably.increases the cells’ sensitivity.to various ty.es of DNA damaging agents, such as ionizing radiation, ultraviolet irradiation, hy.rogen peroxide, and mitomy.in C. We also provide evidence that the drSbcD protein play. an important role in both growth and DNA repair in this organ- ism, especially.in repair of DSBs generated after cellular exposure to 6000 Gy.of IR. These results demonstrate that the drSbcD protein play. an important role in DSBs repair in D. radiodurans.

关键词：辐射阻抗细菌基因分析泛函分析 DNA修补