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Explanations of the DAMPE high energy electron/positron spectrum in the dark matter annihilation and pulsar scenarios

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Science China(Physics,Mechanics & Astronomy) 2018年第10期61卷 19-29页

作者： bingbing wang XiaoJun Bi SuJie Lin PengFei Yin Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China University of Chinese Academy of Sciences Beijing 100049 China

Many studies have shown that either the nearby astrophysical source or dark matter （DM） annihilation/decay can be used to explain the excess of high energy cosmic ray （CR） e^±which is detected by many experiments, such as PAMELA and AMS-02. Recently, the dark matter particle explorer （DAMPE） collaboration has reported its first result of the total CR e^± spectrum from 25 GeV to 4.6TeV with high precision. In this work, we study the DM annihilation and pulsar interpretations of this result. We show that the leptonic DM annihilation channels to r＋＇/＂-, 4p, 4＂/＇, and mixed charged lepton final states can well explain the DAMPE e^± spectrum. We also find that the mixed charged leptons channel would lead to a sharp drop structure at - TeV. However, the ordinary DM explanations have been almost excluded by the constraints from the observations of gamma-ray and CMB, unless some exotic DM models are introduced. In the pulsar scenario, we analyze 21 nearby known pulsars and assume that one of them dominantly contributes to the high energy CR e^± spectrum. Involving the constraint from the Fermi-LAT observation of the e^± anisotropy, we find that two pulsars could explain the DAMPE e^± spectrum. Our results show that it is difficult to discriminate between the DM annihilation and single pulsar explanations of high energy e^± with the current DAMPE result.

关键词： cosmic rays dark matter pulsars

Flexible Vis/NIR wireless sensing system for banana monitoring

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Food Quality and Safety 2023年第3期7卷 492-502页

作者： Meng wang bingbing wang Ruihua Zhang Zihao Wu Xinqing Xiao College of Engineering China Agricultural UniversityBeijingChina

Objectives:The quality of the fruit seriously affects the economic value of the *** quality is related to many ripening parameters,such as soluble solid content(SSC),pH,and firmness(FM),and is a complex *** methods are inefficient,do not guarantee quality,and do not adapt to the current rhythm of the fruit *** this paper,a was designed and implemented for quality prediction and maturity level classification of Philippine Cavendish *** and Methods:The quality changes of bananas in different stages were *** light intensity reflectance values for each maturity stage were compared to conventionally measured SSC,FM,PH,and color ***:Our device can be compared with traditional forms of quality *** experimental results show that the established predictive model with specific preprocessing and modeling algorithms can effectively determine various banana quality parameters(SSC,pH,FM,L^(*),a^(*),and b^(*)).The RPD values of SSC and a^(*)were greater than 3.0,the RPD values of L^(*)and b^(*)were between 2.5 and 3.0,and the pH and FM were between 2.0 and *** addition,a new banana maturity level classification method(FSC)was proposed,and the results showed that the method could effectively classify the maturity level classes(*** maturity levels)with an accuracy rate of up to 97.5%.Finally,the MLR and FSC models are imported into the MCU to realize the near-range and long-range real-time display of ***:These methods can also be applied more broadly to fruit quality detection,providing a basic framework for future research.

关键词： Banana Vis/NIR flexibility ripening classification chemometrics

Construction of 1D Heterostructure NiCo@C/ZnO Nanorod with Enhanced Microwave Absorption

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Nano-Micro Letters 2021年第11期13卷 230-245页

作者： Jianwei wang Zirui Jia Xuehua Liu Jinlei Dou Binghui Xu bingbing wang Guanglei Wu State Key Laboratory of Bio‑Fibers and Eco‑Textiles Institute of Materials for Energy and EnvironmentCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071People’s Republic of China College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071ShandongPeople’s Republic of China Weihai Innovation Institute Qingdao UniversityWeihai 264200ShandongPeople’s Republic of China

Layered double hydroxides(LDHs)have a special structure and atom composition,which are expected to be an excellent electromagnetic wave(EMW)***,it is still a problem that obtaining excellent EMWabsorbing materials from ***,we designed heterostructure NiCo-LDHs@ZnO nanorod and then subsequent heat treating to derive NiCo@C/ZnO ***,with the synergy of excellent dielectric loss and magnetic loss,an outstanding absorption performance could be achieved with the reflection loss of−60.97 dB at the matching thickness of 2.3 mm,and the widest absorption bandwidth of 6.08 GHz was realized at 2.0 ***,this research work provides a reference for the development and utilization of LDHs materials in the field of microwave absorption materials and can also provide ideas for the design of layered structural absorbers.

关键词： Layered double hydroxides NiCo@C/ZnO Interface polarization Microwave absorption

Differences and dynamics of multidimensional poverty in rural China from multiple perspectives analysis

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Journal of Geographical Sciences 2022年第7期32卷 1383-1404页

作者： wang bingbing LUO Qing CHEN Guangping ZHANG Zhe JIN Pingbin School of Earth Sciences Zhejiang UniversityHangzhou 310013China Institute for Geography&Spatial Information Zhejiang UniversityHangzhou 310013China College of Resources and Environment Henan University of Economics and LawZhengzhou 450046China Zhejiang Provincial Key Laboratory of Geographic Information Science Hangzhou 310013China

Absolute poverty was completely eliminated in China in ***,poverty measured by income does not fully reflect the actual *** paper analyses multidimensional poverty and its dynamics in rural China from perspectives of region,terrain,and geographical location during 2010–*** use the Chinese Family Panel Survey data,adopt the Alkire-Foster method and improve the multidimensional poverty index(MPI),calculating and comparing multidimensional poverty and its dynamics among 3009 rural *** addition,the contribution of the indicator to multidimensional poverty is *** results indicate that multidimensional poverty has obvious regional differences,topographical differences,and geographical ***,the targeted poverty alleviation policy has a significant impact on multidimensional poverty eradication,and the rate of decline of the MPI during 2016–2018 is significantly greater than that of 2010–*** contributes more than 50%to the *** general,the proportion of households with persistent multidimensional poverty is higher than temporary multidimensional poverty,and temporary multidimensional poverty is higher than no multidimensional *** results obtained from a large scale,long time and multiple perspectives could offer new insights for the government to further consolidate the results of poverty alleviation while offering China’s experience to other developing countries.

关键词： multidimensional poverty dynamics regional differences geographical location differences topographical differences rural China

Metal-organic framework-derived CoSn/NC nanocubes as absorbers for electromagnetic wave attenuation

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Journal of Materials Science & Technology 2022年第13期108卷 236-243页

作者： Chenxi wang Zirui Jia Shuangqiao He Jixi Zhou Shuo Zhang Mengli Tian bingbing wang Guanglei Wu Institute of Materials for Energy and Environment State Key Laboratory of Bio-fibers and Eco-textilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071China Weihai Innovation Institute Qingdao UniversityWeihai 264200China

Metal-organic framework-derived composites have been widely used in electromagnetic wave(EMW)absorption,but the traditional synthetic strategy greatly limits the structure and species of *** research provided a solvent-free method to synthesize Co-MOF and its *** CoSnO_(3)as the precursor,the preparation of Co-MOF is achieved by bridging the cobalt(II)ion of CoSnO_(3)and the 2-methylimidazole *** CoSn/N-doped carbon(CoSn/NC)composites derived from CoSnO_(3)-MOF(Co-MOF with CoSnO_(3)as Co source)retain the original morphology of CoSnO_(3).Besides,the polarization effect produced by the N-doped carbon layers also benefits the excellent EMW absorption performance of the CoSn/NC *** is reflected in the minimum reflection loss(RL)of-48.2 dB at 2.2 mm and the effective bandwidth(EBA)of 5.84 *** work provides a new channel to the construction of Co-MOFs,which could be extended to other Co-based oxides and vastly expand the species of MOFs based on metallic Co.

关键词： Hollow nanocubes structure N-doped carbon CoSnO_(3)-MOF Electromagnetic wave absorption

Synthesis of MnxOy@C hybrid composites for optimal electromagnetic wave absorption capacity and wideband absorption

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Journal of Materials Science & Technology 2022年第8期103卷 157-164页

作者： Yue Liu Xuehua Liu Xinyu E bingbing wang Zirui Jia Qingguo Chi Guanglei Wu Institute of Materials for Energy and Environment State Key Laboratory of Bio-fibers and Eco-textilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China Key Laboratory of Engineering Dielectrics and Its Application Ministry of EducationSchool of Electrical&Electronic EngineeringHarbin University of Science and TechnologyHarbin 150080China

The fabrication of high-performance electromagnetic(EM)wave absorption(EMA)materials is an effective strategy to deal with ever-increasing EM *** this work,a series of manganese oxides/porous carbon(Mn_(x)O_(y)@C)hybrid composites are obtained by a two-step *** is revealed that different manganese oxides play various influence on the dielectric properties of *** to the moderate complex permittivity of MnO@C hybrid composites,the optimal reflection loss could reach as high as-76.0 dB at the matching thickness of 2.0 mm with 5.2 GHz of effective absorption bandwidth at thickness of 2.1 *** demonstrated that the addition of porous carbon is vital for enhancing EMA performance of composites,which not only coordinates impedance matching allowing more EM waves enter the absorber,but also provides the path for electron movement,thus profiting conductive ***,different heterogeneous interfaces including porous carbon,manganese oxide and so on,are conducive to contribution of interface *** most noteworthy is ingenious design of composite materials and systematic research of EM energy attenuation mechanism in this work will provide the possibility to realize high-performance EMA.

关键词： Manganese oxide/carbon composites Dielectric loss Relaxation time Electromagnetic wave absorption

Spatial Patterns of LULC and Driving Forces in the Transnational Area of Tumen River:A Comparative Analysis of the Sub-regions of China,the DPRK,and Russia

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Chinese Geographical Science 2020年第4期30卷 588-599页

作者： NAN Ying wang bingbing ZHANG Da LIU Zhifeng QI Dekang ZHOU Haohao College of Geography and Ocean Sciences Yanbian UniversityYanji Jilin133002China Center for Human-Environment System Sustainability(CHESS) State Key Laboratory of Earth Surface Processes and Resource Ecology(ESPRE)Beijing Normal UniversityBeijing 100875China School of Natural Resources Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

Understanding the spatial patterns of land-use and land-cover(LULC)and their driving forces in transnational areas is important for the sustainable development of these ***,the spatial patterns of LULC and their driving forces across multiple scales are poorly understood in transnational *** this study,we analyzed the spatial patterns of LULC and driving forces in the transnational area of Tumen River(TATR)in 2016 across two scales:the entire region and the sub-regions of China,the Democratic People’s Republic of Korea(DPRK),and *** showed that the LULC was dominated by broadleaf forest and dry farmland in the TATR in 2016,which accounted for 66.86%and 13.60%of the entire region,***,the LULC in the three sub-regions exhibited noticeable *** the Chinese and the DPRK’s sub-regions,the area of broadleaf forest was greater than those for the other LULC types,while the Russian sub-region was dominated by broadleaf forest and *** spatial patterns of LULC were mainly influenced by topography,climate,soil properties,and human *** addition,the driving forces of the spatial patterns of LULC in the TATR had an obvious scaling ***,we suggest that effective policies and regulations with cooperation among China,the DPRK,and Russia are needed to plan the spatial patterns of LULC and improve the sustainable development of the TATR.

关键词： land-use and land-cover(LULC) spatial pattern driving force transnational area of Tumen River

Controllable synthesis of Ni/NiO@porous carbon hybrid composites towards remarkable electromagnetic wave absorption and wide absorption bandwidth

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Journal of Materials Science & Technology 2021年第28期87卷 120-132页

作者： Xinfeng Zhou Zirui Jia Xingxue Zhang bingbing wang Wei Wu Xuehua Liu Binghui Xu Guanglei Wu Institute of Materials for Energy and Environment State Key Laboratory of Bio-fibers and Eco-textilesCollege of Materials Science and EngineeringQingdao UniversityQingdao266071China College of Food Science and Engineering Qingdao Agricultural UniverisityQingdao266109China

The reasonable design of the composition of the composite materials is of great significance to optimized the electromagnetic(EM)wave absorption ***,the Ni/NiO@C hybrid composites with tunable Ni proportion were successfully synthesized through a two-step *** the assistance of X-ray diffraction with refinement treatment,the specific proportion of Ni of as-obtained hybrid composites could be *** controlling calcination time to adjust the Ni content of Ni/NiO@C hybrid composites,it has been found that the composite carbonized at 500℃exhibited remarkable EM wave absorption with the minimum reflection loss(RLmin)of-49.1 dB at 4.9 mm and the widest effective absorption bandwidth(EABmax)of 4.56 GHz at 2.1 ***,by adjusting the Ni source,the optimal EM wave absorption performance could be *** illustrated that the N3PC with the Ni proportion of 13.17%showed the RLm inas low as-51.1 dB at 2.4 mm and the EABmax was 5.12 GHz at 2.7 *** is worth noting that this work demonstrates the relevance of the composition and EM wave absorption performance of hybrid composites,which offers a feasible reference for the absorption mechanism of absorber.

关键词： Ni/NiO@C hybrid composites Nickel proportion Multiple-loss mechanism Electromagnetic wave absorption efficiency

Interfacial energy barrier tuning of hierarchical Bi_(2)O_(3)/WO_(3) heterojunctions for advanced triethylamine sensor

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Journal of Advanced Ceramics 2022年第12期11卷 1860-1872页

作者： Mingxin ZHANG Kai LIU Xingmin ZHANG bingbing wang Xinru XU Xinxin DU Chao YANG Kewei ZHANG College of Materials Science and Engineering State Key Laboratory of Bio-Fibers and Eco-TextilesCollaborative Innovation Center for Marine Biomass FibersMaterials and Textiles of Shandong ProvinceQingdao UniversityQingdao 266071China

Traditional triethylamine(TEA)sensors suffer from the drawback of serious cross-sensitivity due to the low charge-transfer ability of gas-sensing ***,an advanced anti-interference TEA sensor is designed by utilizing interfacial energy barriers of hierarchical Bi_(2)O_(3)/WO_(3) *** from abundant slit-like pores,desirable defect features,and amplification effect of heterojunctions,the sensor based on Bi_(2)O_(3)/WO_(3) composite with 40%Bi_(2)O_(3)(0.4-Bi_(2)O_(3)/WO_(3))demonstrates remarkable performance in terms of faster response/recovery time(1.7-fold/1.2-fold),higher response(2.1-fold),and lower power consumption(30℃-decrement)as compared with the pristine WO_(3) ***,the composite sensor exhibits long-term stability,reproducibility,and negligible response towards interfering molecules,indicating the promising potential of Bi_(2)O_(3)/WO_(3) heterojunctions in anti-interference detection of low-concentration TEA in real *** work not only offers a rational solution to design advanced gas sensors by tuning the interfacial energy barriers of heterojunctions,but also provides a fundamental understanding of hierarchical Bi_(2)O_(3) structures in the gas-sensing field.

关键词： Bi_(2)O_(3)/WO_(3) heterojunctions hierarchical structures triethylamine(TEA) gas sensors