检索结果-南通市图书馆

Morphological Classification of Infrared Galaxies Based on WISE

Research in Astronomy and Astrophysics 2024年第4期24卷 222-236页

作者： zhi-Ren Pan Bo Qiu Cui-xiang liu A-li Luo xia Jiang xiao-Yu Guo School of Electronic and Information Engineering Hebei University of TechnologyTianjin 300401China Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

This study introduces a novel convolutional neural network,the WISE Galaxy Classification Network(WGC),for classifying spiral and elliptical galaxies using Wide-field Infrared Survey Explorer(WISE)*** attains an accuracy of 89.03%,surpassing the combined use of K-means or SVM with the Color-Color method in more accurately identifying galaxy *** enhanced variant,WGC_mag,integrates magnitude parameters with image features,further boosting the accuracy to 89.89%.The research also delves into the criteria for galaxy classification,discovering that WGC primarily categorizes dust-rich images as elliptical galaxies,corresponding to their lower star formation rates,and classifies less dusty images as spiral *** paper explores the consistency and complementarity of WISE infrared images with SDSS optical images in galaxy morphology *** SDSS Galaxy Classification Network(SGC),trained on SDSS images,achieved an accuracy of 94.64%.The accuracy reached 99.30% when predictions from SGC and WGC were *** the complementarity of features in WISE and SDSS images,a novel variant of a classifier,namely the Multi-band Galaxy Morphology Integrated Classifier,has been *** classifier elevates the overall prediction accuracy to 95.39%.Lastly,the versatility of WGC was validated in other data *** the HyperLEDA data set,the distinction between elliptical galaxies and Sc,Scd and Sd spiral galaxies was most pronounced,achieving an accuracy of 90%,surpassing the classification results of the Galaxy Zoo 2 labeled WISE data *** research not only demonstrates the effectiveness of WISE images in galaxy morphology classification but also represents an attempt to integrate multi-band astronomical data to enhance understanding of galaxy structures and evolution.

关键词： methods:data analysis infrared:galaxies galaxies:spiral galaxies:elliptical and lenticular cD

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Assessing the concentration and potential health risk of heavy metals in China's main deciduous fruits

引用

Journal of Integrative Agriculture 2016年第7期15卷 1645-1655页

作者： NIE Ji-yun KUANG li-xue li zhi-xia XU Wei-hua WANG Cheng CHEN Qiu-sheng li An ZHAO Xu-bo XIE Han-zhong ZHAO Duo-yong WU Yong-long CHENG Yang Institute of Pomology Chinese Academy of Agricultural Sciences/Laboratory of Quality&Safety Risk Assessment for Fruit(Xingcheng)Ministry of AgricultureXingcheng 125100P.R.China Yantai Academy of Agricultural Sciences Yantai 265500P.R.China Institute of Quality Standards&Testing Technology for Agro-Products Xinjiang Academy of Agricultural SciencesUrumchi 830091P.R.China Institute of Tianjin Agriculture Quality Standard and Testing Technology Tianjin 300381P.R.China Beijing Research Center for Agricultural Standards and Testing Beijing 100097P.R.China College of Food Science and Engineering Northwest A&F UniversityYangling 712100P.R.China Zhengzhou Institute of Pomology Chinese Academy of Agricultural SciencesZhengzhou 450009P.R.China

To assess levels of contamination and human health risk, we analyzed the concentrations of the heavy metals lead （Pb）, cadmium （Cd）, chromium （Cr）, and nickel （Ni） in China’s main deciduous fruits-apple, pear, peach, grape, and jujube. The concentration order of the heavy metals was Ni〉Cr〉Pb〉Cd. In 97.5% of the samples, heavy metal concentrations were within the maximum permissible limits. Among the fruits studied, the heavy metal concentrations in jujube and peach proved to be the highest, and those in grape proved to be the lowest. Only 2.2% of the samples were poluted by Ni, only 0.4% of the samples were poluted by Pb, and no samples were poluted by Cd or Cr. Compared with the other fruits, the combined heavy metal polution was signiifcantly higher （P〈0.05） in peach and signiifcantly lower （P〈0.05） in grape. For the combined heavy metal polution, 96.9% of the samples were at safe level, 2.32% at warning level, 0.65% at light level, and 0.13% at moderate level. In the fruits studied, the contribution of heavy metals to the daily intake rates （DIR） folowed the order of Ni〉Cr〉Pb〉Cd. The highest DIR came from apple, while the lowest DIR came from grape. For each of the heavy metals, the total DIR from ifve studied fruits corresponded to no more than 1.1% of the tolerable daily intake, indicating that no signiifcant adverse health effects are expected from the heavy metals and the fruits studied. The target hazard quotients and the total target hazard quotients demonstrated that none of the analyzed heavy metals may pose risk to consumers through the fruits studied. The highest risk was posed by apple, folowed in decreasing order by peach and pear, jujube, and grape. We suggest that the main deciduous fruits （apple, pear, peach, grape, and jujube） of China’s main producing areas are safe to eat.

关键词： deciduous fruits heavy metals health risk assessment China

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Producing circularly polarized luminescence by radiative energy transfer from achiral metal-organic cage to chiral organic molecules

引用

Chinese Chemical Letters 2024年第8期35卷 498-502页

作者： Zhao-xia lian Xue-zhi Wang Chuang-Wei Zhou Jiayu li Ming-De li xiao-Ping Zhou Dan li College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and ApplicationsJinan UniversityGuangzhou 510632China College of Chemistry and Chemical Engineering Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong ProvinceShantou UniversityShantou 515063China

The development of circularly polarized luminescence(CPL)materials with high performance is signifi-cantly ***,we develop a facial strategy for fabricating a CPL-active system by employing an achiral luminescent metal-organic cage(MOC)and chiral boron dipyrromethene(BODIPY)*** is achieved by taking advantage of the radiative energy transfer process,in which BODIPY molecules act as energy acceptors and MOCs act as *** CPL performance(maximum luminescence dissymme-try factor up to±1.5×10^(−3))can be tuned by adjusting the ratio between MOCs and ***-light emission with the CPL feature is obtained by using a ternary system including MOC,chiral BODIPY,and Rhodamine *** present work provides a facile and universal strategy to construct a CPL-active system by integrating achiral luminophores and chiral molecules.

关键词： Circularly polarized luminescence Metal-organic cage Radiative energy transfer Chiral small molecules Bodipy Chirality

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Research of Underwater Bottom Object and Reverberation in Feature Space

引用

Journal of Marine Science and Application 2013年第2期12卷 235-239页

作者： Xiukun li zhi xia Science and Technology on Underwater Acoustic Laboratory Harbin Engineering University Harbin 150001 China

The critical technical problem of underwater bottom object detection is founding a stable feature space for echo signals classification. The past literatures more focus on the characteristics of object echoes in feature space and reverberation is only treated as interference. In this paper, reverberation is considered as a kind of signal with steady characteristic, and the clustering of reverberation in frequency discrete wavelet transform （FDWT） feature space is studied. In order to extract the identifying information of echo signals, feature compression and cluster analysis are adopted in this paper, and the criterion of separability between object echoes and reverberation is given. The experimental data processing results show that reverberation has steady pattern in FDWT feature space which differs from that of object echoes. It is proven that there is separability between reverberation and object echoes.

关键词： underwater bottom object pattern of reverberation feature clustering feature space underwater object detection

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Pd cluster decorated free standing flexible cathode for high performance li-oxygen batteries

引用

Nano Research 2024年第4期17卷 2678-2686页

作者： liang Guo Guoliang Zhang Ruonan Yang Dongmei Zhang Xiuqi Zhang Han Yu xia li Feng Dang Key Laboratory for liquid-Solid Structure Evolution and Processing of Materials Ministry of EducationShandong UniversityJinan 250061China

As a promising candidate for the next generation energy storage system,rechargeable lithium-oxygen batteries(LOBs)still face substantial challenges caused by insulating discharge products that preclude their practical *** highly efficient cathode catalysts capable of facilitating formation/decomposition of discharge products is considered as an essential approach towards high performance ***,Pd decorated Te nanowires(Pd@Te NWs)were synthesized as advanced catalyst in LOBs to maximize Pd utilization and achieve synergistic effect,in which Pd clusters were uniformly grown on Te substrate though regulating the Pd:Te ***,Pd@Te nanowires assembled into an interpenetrating network-like structure by vacuum filtration and employed as flexible cathode,enabling LOBs achieved an ultralong 190 cycles stability and a superior specific capacity of 3.35 mAh·cm^(-2).Experimental studies and density functional theory(DFT)calculations reveal the excellent catalytic ability of Pd@Te and synergistic catalytic mechanism of Pd and Te,in which uniform electron distribution,extensive electron exchange,and large adsorption distance between Pd cluster and discharge products promote homogeneous adsorption/desorption of discharge products,while the high adsorption energy of Te substrate for li species reduces the initial dynamical energy barrier during discharging *** current work provides viable strategy to design composite catalysts for flexible cathode of LOBs with synergistic catalytic effects.

关键词： flexible lithium-oxygen batteries Pd@Te synergistic catalysis cathode catalysts density functional theory(DFT)calculation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Graphdiyne(C_(n)H_(2n-2))as an"electron transfer bridge"boosting photocatalytic hydrogen evolution over Zn_(0.5)Co_(0.5)S/MoS_(2)S-scheme heterojunction

引用

Rare Metals 2024年第5期43卷 1999-2014页

作者： Mei li Jing-zhi Wang zhi-liang Jin School of Chemistry and Chemical Engineering North Minzu UniversityYinchuan 750021China School of Chemistry and Chemical Engineering Ningxia Key Laboratory of Solar Chemical Conversion TechnologyKey Laboratory for Chemical Engineering and TechnologyState Ethnic Affairs CommissionNorth Minzu UniversityYinchuan 750021China

In the process of photocatalytic water cracking,the migration rate and utilization rate of photogenerated charges determine the hydrogen evolution performance of the *** this paper,a carbon isotope superconducting material graphdiyne(GDY)is prepared by mechanical ball milling and introduced into the S-scheme heterojunction Zn_(0.5)Co_(0.5)S/MoS_(2)inorganic *** terms of hydrogen evolution kinetics,GDY acts as an electron bridge,not only accelerating the migration of photogenerated carriers but also improving the utilization of photogenerated ***,the large twodimensional layer provides more loading and anchoring points for Zn_(0.5)Co_(0.5)S/MoS_(2),which increases the number of active *** ternary composite catalyst 20%GDY/Zn_(0.5)Co_(0.5)S/MoS_(2)(20-GCSM)generates 69.94μmol of hydrogen(5 h)in triethanolamine *** is 2.97 and1.80 times higher than Zn_(0.5)Co_(0.5)S and Zn_(0.5)Co_(0.5)S/MoS_(2),*** the cyclic experiment,it still has stable hydrogen evolution performance after standing for24 h(under dark conditions).In addition,the potential mechanism of photocatalytic hydrogen evolution is demonstrated through in-situ X-ray photoelectron *** work provides a reference for further research in the field of introducing carbon materials into photocatalytic systems and improving the utilization of photogenerated charges.

关键词： Graphdiyne S-scheme heterojunction Electron transfer bridge Hydrogen production

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Isotopic dependence of the yield ratios of light fragments from different projectiles and their unified neutron skin thicknesses

引用

Nuclear Science and Techniques 2024年第3期35卷 228-236页

作者： Ting-zhi Yan Shan li School of Energy and Power Engineering Northeast Electric Power UniversityJilin 132012China

The yield ratios of neutron-proton(R(n/p))and^(3)H-^(3)He(R(^(3)H∕^(3)He))with reduced rapidity from 0 to 0.5 were simulated at 50 MeV/u even-even ^(36−56)Ca+^(40)Ca,even-even ^(48−78)Ni+^(58)Ni,and ^(100−139)Sn(every third isotopes)+112 Sn for full reduced impact parameters using the isospin-dependent quantum molecular dynamics(IQMD)*** neutron and proton density distributions and root-mean-square radii of the reaction systems were obtained using the Skyrme-Hartree-Fock model,which was used for the phase space initialization of the projectile and target in *** defined the unified neutron skin thickness asΔRnp=^(1∕2) n−^(1∕2)p,which was negative for neutron-deficient *** unifiedΔRnp values for nuclei with the same relative neutron excess from different isotopic chains were nearly equal,except for extreme neutron-rich isotopes,which is a type of scaling *** yield ratios of the three isotopic chain-induced reactions,which depended on the reduced impact parameter and unified neutron skin thickness,were *** results showed that both R(n/p)and R(^(3)H∕^(3)He)decreased with a reduced impact parameter for extreme neutron-deficient isotopes;however,they increased with reduced impact parameters for extreme neutron-rich isotopes,and increased with theΔRnp of the projectiles for all reduced impact *** addition,a scaling phenomenon was observed betweenΔR np and the yield ratios in peripheral colli-sions from different isotopic chain projectiles(except for extreme neutron-rich isotopes).Thus,R(n/p)and R(^(3)H∕^(3)He)from peripheral collisions were suggested as experimental probes for extracting the neutron or proton skin thicknesses of non-extreme neutron-rich nuclei from different isotopic chains.

关键词： Exotic nuclei Unified neutron skin thickness Yield ratios IQMD

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Holographic superfluid ring with a weak link

引用

Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 29-38页

作者： zhi-Hong li Huai-Fan li Department of Physics Shanxi Datong UniversityDatong 037009China Institute of Theoretical Physics Shanxi Datong UniversityDatong 037009China

We explore the generation of topological defects in the course of a dynamical phase transition in a ring with a weak link, i.e., a SSS Josephson junction, from the AdS/CFT correspondence. By setting different parameters of the junction(width, steepness,depth) and the final temperature of the quench, the configurations of the charge density and condensate of the order parameters of the dual field theory are presented. Meanwhile, we observe that in the final equilibrium state, variations in parameters of the junctions only affect the configurations of the charge density and condensate of the order parameters, without altering their values outside the junction. However, variations in the final temperature will directly affect the values of the charge density and condensate of the order parameters outside of the junction. Moreover, in the final equilibrium state, we propose an analytic relation between the gauge-invariant velocity in the two superconducting states in the SSS Josephson junction, which agrees well with the numerical results.

关键词： AdS/CFT correspondence holographic superfluid holographic Josephson junction

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A regularization algorithm of dynamic light scattering for estimating the particle size distribution of dual-substance mixture in water

引用

Particuology 2024年第6期89卷 246-257页

作者： Yanghong Wang Ziqiang Meng Zipei Zhang Min xia li xia Wei li School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China

Dynamic light scattering(DLS)is a nondestructive,well-established technique for the size characterization of proteins,nanoparticles,polymers,and colloidal ***,current DLS techniques are only applied to particle groups of single composition due to the limitation of their inversion *** this study,we propose a particle size distribution inversion algorithm based on the Tikhnonov regularization method that can be applied to the dual-substance particle *** algorithm retrieves the particle size distributions of two substances,respectively,by taking advantage of their refractive index *** simulation results reveal that the algorithm has excellent accuracy and stability when the scattering angle is 30°.Instead of the original identity matrix,the first-order difference matrix and second-order difference matrix are used as the regular matrix when utilizing the Tikhnonov algorithm,which obviously improves the anti-interference,accuracy,and stability of the ***,the inversion of particle size distribution is carried out at a 0.01%–1%noise level,which shows that the algorithm has an available antinoise ***,experimental particle size measurements for a mixture of polystyrene beads and toner particles demonstrate that the proposed algorithm is superior to the traditional Tikhnonov algorithm in applicability and accuracy.

关键词： Dynamic light scattering Dual-substance mixture Particle sized istribution Tikhnonov regularization

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Cyclic Pulsating Pressure Enhanced Segregating Structuration of Ultra-High Molecular Weight Polyethylene/Graphene Composites as High-performance light-Weight EMI Shields

引用

Chinese Journal of Polymer Science 2024年第7期42卷 958-967,I0008页

作者： Yun-zhi Huang xiao-xiao liu Lan-Wei li Guang-Ming Huang Zhao-xia Huang Jin-Ping Qu National Engineering Research Center of Novel Equipment for Polymer Processing Key Laboratory of Polymer Processing EngineeringMinistry of EducationGuangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced ManufacturingSchool of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou 510641China School of Advanced Manufacturing Technology Guangdong Mechanical&Electrical PolytechnicGuangzhou 510550China

Currently,the enhancement in electromagnetic interference(EMI)performance of polymeric composite generally relies on either improving electrical conductivity(σ)for stronger electromagnetic(EM)reflections or tailoring structure for higher EM ***,we proposed a novel technique called cyclic pulsating pressure enhanced segregating structuration(CPP-SS),which can reinforce these two factors *** structural information was supplied by optical microscopy(OM)and scanning electron microscopy(SEM),both of which confirmed the formation and evolution of segregate structured ultra-high molecular weight polyethylene(UHMWPE)/graphene ***,the result showed that CPP-SS can significantly improve theσof ***,advanced specific EMI shielding efficiency of 31.1 d B/mm was achieved for UHMWPE/graphene composite at 1-mm thickness and a low graphene loading of 5 wt%.Meanwhile,it also confirmed that the intrinsic disadvantage of poor mechanical properties of conventional segregated structure composites can be *** work is believed to provide a fundamental understanding of the structural and performance evolutions of segregated structured composites prepared under CPPSS,and to bring us a simple and efficient approach for fabricating high-performance,strong and light-weight polymeric EMI shields.

关键词： Cyclic pulsating pressure Segregated structure Ultra-high molecular weight polyethylene Graphene Electromagnetic interface

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：