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Geomorphology-oriented theoretical framework and construction method for value-added deM

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Journal of Geographical Sciences 2024年第1期34卷 165-184页

作者： ZHANG Haiping tang Guoan XIONG Liyang YANG xin LI Fayuan Key Laboratory of Virtual Geographic Environment Ministry of EducationNanjing Normal UniversityNanjing 210023China School of Geography Nanjing Normal UniversityNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource development and Application Nanjing 210023China

Digital elevation model(deM)plays a fundamental role in the study of the earth system by expressing surface configuration,understanding surface process,and revealing surface *** is widely used in analysis and modeling in the field of ***,traditional deM has the defect of single attribute,which is difficult to support the research in earth system science oriented to geoscience process and mechanism ***,realizing the value-added data model on the basis of traditional deM is necessary to serve digital elevation modeling and terrain analysis under the background of a new geomorphology research paradigm and earth observation technology.A theoretical framework for value-added deM that mainly includes concept,connotation,content,and categories,is constructed in this *** relationship between different types of value-added deMs as well as the research significance and application category of this theoretical framework are also *** following are different methods of value-added deMs:(1)value-added methods of deM space and time dimensions that emphasize the integration of the ground and underground as well as coupling of time and space,(2)attribute-based value-added methods composed of material(including underground,surface,and ground)and morphological properties,and(3)value-added methods of features and physical elements that consider geographical objects and landform features formed by natural processes and artificial *** digital terrace,slope,and watershed models are used as examples to illustrate application scenarios of the three kinds of value-added *** study aims to improve expression methods of deMs under the background of new surveying and mapping technologies by adding value to the deM at three levels of dimensions,attributes,and elements as well as support knowledge-driven digital geomorphological analysis in the era of big data.

关键词： spatial data model value-added deM digital terrain analysis geomorphological ontology geomorphology

Effect of spacer length on the liquid crystalline property of azobenzene-containing ABA-type triblock copolymers via ATRP

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Chinese Chemical Letters 2007年第9期18卷 1129-1132页

作者： xin de tang Long Cheng Gao xing He Fan Qi Feng Zhou Institute of New Materials Shandong Jiaotong UniversityJi’nan 250023China department of Polymer Science and Engineering College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

The effect of flexible spacer length on the liquid crystalline property of ABA-type triblock copolymers containing azobenzene groups was investigated. For the study, the monomers, n-[4-(4-ethoxyphenylazo)phenoxy]alkyl methacrylates with varying methylene groups (n = 0, 2, 6) were used to synthesize a series of azobenzene-containing amphiphilic triblock copolymers PAnC–PEG–PAnC by atom transfer radical polymerization (ATRP). Differential scanning calorimetry (DSC), polarizing optical microscopy (POM), and one-dimensional X-ray diffraction (1D WAXD) have shown that the glass transition temperatures of these copolymers decreased with increasing n, PA0C–PEG–PA0C has no mesophase, while both PA2C–PEG–PA2C and PA6C–PEG–PA6C have a nematic mesophase. These differences derive from the length of spacer groups between the polymer backbone and side-chain LC monomers.

关键词： Spacer group Liquid crystalline property Azobenzene Triblock copolymer Atom transfer radical polymerization (ATRP)

Synthesis and characterization of H-type amphiphilic liquid crystalline block copolymers by ATRP

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Chinese Chemical Letters 2008年第2期19卷 237-240页

作者： xin de tang Long Cheng Gao xing He Fan Qi Feng Zhou Institute of New Materials Shandong Jiaotong University Ji＇nan 250023 China department of Polymer Science and Engineering College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

H-type amphiphilic liquid crystalline block copolymers containing azobenzene were synthesized by atom transfer radical polymerization （ATRP）. Macroinitiators prepared by the esterification between poly（ethylene oxide）（PEG） and 2,2-dichloroacetyl chloride were utilized to initiate the polymerization of 6-[4-（4-ethoxyphenylazo）phenoxy]hexyl rnethacrylate （M6C）. The resulting macroinitiators and block copolymers were characterized by ^1H NMR, gel permeation chromatography （GPC）. Polarizing optical microscopy （POM） and differential scanning calorimetry （DSC） preliminarily revealed the liquid crystalline property of these block copolymers. This series of liquid crystalline block copolymers are promising in some areas, such as optical data storage, optical switch, and molecular devices.

关键词： H-type Amphiphilic Block copolymer Liquid crystalline property Atom transfer radical polymerization (ATRP)

Emerging memristors and applications in reservoir computing

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Frontiers of physics 2024年第1期19卷 219-239页

作者： Hao Chen xin-Gui tang Zhihao Shen Wen-Tao Guo Qi-Jun Sun Zhenhua tang Yan-Ping Jiang School of Physics and Optoelectronic Engineering Guangdong University of TechnologyGuangzhou Higher Education Mega CenterGuangzhou 510006China

Recently, with the emergence of ChatGPT, the field of artificial intelligence has garnered widespread attention from various sectors of society. Reservoir Computing (RC) is a neuromorphic computing algorithm used to analyze time-series data. Unlike traditional artificial neural networks that require the weight values of all nodes in the trained network, RC only needs to train the readout layer. This makes the training process faster and more efficient, and it has been used in various applications, including speech recognition, image classification, and control systems. Its flexibility and efficiency make it a popular choice for processing large amounts of complex data. A recent research trend is to develop physical RC, which utilizes the nonlinear dynamic and short-term memory properties of physical systems (photonic modules, spintronic devices, memristors, etc.) to construct a fixed random neural network structure for processing input data to reduce computing time and energy. In this paper, we introduced the recent development of memristors and demonstrated the remarkable data processing capability of RC systems based on memristors. Not only do they possess excellent data processing ability comparable to digital RC systems, but they also have lower energy consumption and greater robustness. Finally, we discussed the development prospects and challenges faced by memristors-based RC systems.

关键词： reservoir computing memristor resistive switching artificial synapse neuromorphic computing

P-and SV-wave dispersion and attenuation in saturated microcracked porous rock with aligned penny-shaped fractures

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Petroleum Science 2024年第1期21卷 143-161页

作者： Sheng-Qing Li Wen-Hao Wang Yuan-Da Su Jun-xin Guo Xiao-Ming tang School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Laoshan National Laboratory Qingdao 266071ShangdongChina Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology Southern University of Science and TechnologyShenzhen 518055GuangdongChina department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055GuangdongChina

P-and SV-wave dispersion and attenuation have been extensively investigated in saturated poroelastic media with aligned ***,there are few existing models that incorporate the multiple wave attenuation mechanisms from the microscopic scale to the macroscopic ***,in this work,we developed a unified model to incorporate the wave attenuation mechanisms at different scales,which includes the microscopic squirt flow between the microcracks and pores,the mesoscopic wave-induced fluid flow between fractures and background(FB-WIFF),and the macroscopic Biot's global flow and elastic scattering(ES)from the *** tang's modified Biot's theory and the mixed-boundary conditions,we derived the exact frequency-dependent solutions of the scattering problem for a single penny-shaped fracture with oblique incident P-and *** then developed theoretical models for a set of aligned fractures and randomly oriented fractures using the Foldy *** results indicated that microcrack squirt flow considerably influences the dispersion and attenuation of P-and SV-wave *** coupling effects of microcrack squirt flow with the FB-WIFF and ES of fractures cause much higher velocity dispersion and attenuation for P waves than for SV *** oriented fractures substantially reduce the attenuation caused by the FB-WIFF and ES,particularly for the ES attenuation of SV *** a comparison with existing models in the limiting cases and previous experimental measurements,we validated our model.

关键词： Aligned fractures P-and SV-wave Dispersion and attenuation Microcracked porous background FB-WIFF Elastic scattering Squirt flow

Self-cleaning SERS sensor based on flexible Ni_(3)S_(2)/MoS_(2)@Ag@PDMS composites for label-free multiplex volatile organic compounds detection

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Nano Research 2024年第6期17卷 5529-5539页

作者： xinyue Song Yongzheng Zhang Xiaohui Ren Dongyan tang Xuelin Zhang xin Li MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringState Key Lab of Urban Water Resource and EnvironmentHarbin Institute of TechnologyHarbin 150090China College of Textile and Clothing Yancheng Institute of TechnologyYancheng 224051China MEMS Center Harbin Institute of TechnologyHarbin 150001China

Flexible self-cleaning surface-enhanced Raman scattering(SERS)sensors are highly desirable for the detection of various environmental pollutants,including volatile organic compounds(VOCs).However,achieving sensitive detection without labeling and ensuring efficient cyclic use remain significant ***,we introduce a direct approach to create a versatile Ni_(3)S_(2)/MoS_(2)@Ag@PDMS(PDMS=polydimethylsiloxane)composite SERS substrate using chemical vapor deposition *** produced substrate shows outstanding performance,offering extremely low detection sensitivity(1.0×10^(−12)M 4-aminobenzenethiol)and high enhancement factors(approximately 107).The interactions between the rod-shaped Ni_(3)S_(2)/MoS_(2)@Ag heterostructure and the molecules facilitate the transfer of charge,resulting in an increased electric field enhancement of the exciton *** has the dual benefit of providing a self-cleaning effect and enhancing SERS ***,the substrate enables sensitive detection of VOCs gas molecules without the need for labels,achieving a minimum detectable concentration as low as 1 ppm for o-dichlorobenzene,due to the preconcentration effect of *** calculations further explain the combined effect of electromagnetic and chemical enhancement in this composite *** utilizing the developed visual SERS barcode,quick multiple detection and analysis of mixtures can be *** flexible and versatile SERS technique has significant potential for on-site detection and analysis of environmental pollutants,opening the doors for the development of a wearable in-situ SERS sensing platform.

关键词： surface-enhanced Raman scattering(SERS) quantitative detection recyclable detection volatile organic compounds(VOCs) chemical vapor deposition(CVD)

The modulatory effect of oolong tea polyphenols on intestinal flora and hypothalamus gene expression in a circadian rhythm disturbance mouse model

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Food Science and Human Wellness 2024年第2期13卷 748-764页

作者： Ruonan Yan Chi-tang Ho Yanan Liu Shengnan Zhan Zufang Wu xin Zhang department of Food Science and Engineering Ningbo UniversityNingbo 315211China department of Food Science Rutgers UniversityNew BrunswickNew Jersey 08901USA

The interaction between host circadian rhythm and gut microbes through the gut-brain axis provides new clues for tea polyphenols to improve host *** present research showed that oolong tea polyphenols(OTP)improved the structural disorder of the intestinal flora caused by continuous darkness,thereby modulating the production of metabolites related to pyruvate metabolism,glycolysis/gluconeogenesis,and tryptophan metabolism to alleviate the steady-state *** fecal microbiota transplantation from the OTP group,the single-cell transcriptomic analysis revealed that OTP significantly increased the number of hypothalamus cell clusters,up-regulated the number of astrocytes and fibroblasts,and enhanced the expression of circadian rhythm genes Cry2,Per3,Bhlhe41,Nr1d1,Nr1d2,Dbp and Rorb in hypothalamic *** results confirmed that OTP can actively improve the intestinal environmental state as well as internal/peripheral circadian rhythm disorders and cognitive impairment,with potential prebiotic functional characteristics to notably contribute to host health.

关键词： Gut microbiota Circadian rhythm Oolong tea polyphenols Single-cell sequencing Metabolism

Long-term exposure to aryl hydrocarbon receptor agonist neburon induces reproductive toxicity in male zebrafish(Danio rerio)

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Journal of Environmental Sciences 2024年第8期142卷 193-203页

作者： Fucong Zhang Chen tang Yue Zhu Qian Wang xin Huang Chunyan Yang Chengyong He Zhenghong Zuo Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems School of Life SciencesXiamen UniversityXiamen 361102China

Neburon is a phenylurea herbicide that is widely used worldwide,but its toxicity is poorly *** our previous study,we found that neburon has strong aryl hydrocarbon receptor(AhR)agonist activity,but whether it causes reproductive toxicity is not *** the present study,zebrafish were conducted as a model organism to evaluate whether environmental concentrations of neburon(0.1,1 and 10μg/L)induce reproductive disorder in *** exposure to neburon for 150 days from embryo to adult,that the average spawning egg number in high concentration group was 106.40,which was significantly lower than 193.00in control *** result was mainly due to the abnormal male reproductive behavior caused by abnormal transcription of genes associated with reproductive behavior in the brain,such as *** proportions of spermatozoa in the medium and high concentration groups were 82.40%and 83.84%,respectively,which were significantly lower than 89.45%in control *** result was mainly caused by hormonal disturbances and an increased proportion of apoptotic *** hormonal disruption was due to the significant changes in the transcription levels of key genes in the hypothalamus-pituitary-gonadal axis following neburon *** treatment also significantly activated the AhR signaling pathway,causing oxidative stress damage and eventually leading to a significant increase in apoptosis in the exposed ***,these data filled the currently more vacant profile of neburon toxicity and might provide information to assess the ecotoxicity of neburon on male reproduction at environmentally relevant concentrations.

关键词： Zebrafish Neburon Male reproductive toxicity HPG axis AhR agonist

Masses of the conjectured H-dibaryon at different temperatures

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Chinese Physics C 2024年第8期48卷 83-93页

作者： Liang-Kai Wu Han tang Ning Li xin-Yang Wang School of Physics and Electronic Engineering Jiangsu UniversityZhenjiang 212013China Center for Fundamental Physics School of Mechanics and PhysicsAnhui University of Science and TechnologyHuainan 232001China

We present a lattice QCD determination of masses of the conjectured H-dibaryon,denoted as mH,at nine different temperatures:T/T_(c)=0.24,0.63,0.76,0.84,0.95,1.09,1.27,1.52,and *** masses of baryons N,Σ,Ξ,andΛat different temperatures were also *** simulations were performed on an anisotropic lattice with N_(f)=2+1 flavours of clover fermion at a quark mass corresponding to mπ=384(4)*** thermal ensembles were provided by the FASTSUM collaboration,whereas the zero temperature ensembles were provided by the Hadspec *** also calculated the spectral density of the correlation function of those *** spectral density distributions show a rich peak structure at the lowest temperature;at intermediate temperatures,the mass values of those particles obtained by the extrapolation method reflect a two-peak *** the spectral density for the octet baryon becomes smooth at T/T_(c)=1.27,1.52,and 1.90,the spectral density for the H-dibaryon becomes smooth at T/T_(c)=*** T/T_(c)=0.24,the mass difference of the H-dibaryon andΛpair,expressed asΔm=m_(H)−2m_(Λ),was estimated to beΔm=−14.6(6.2)MeV,which suggests the existence of a bound H-dibaryon state.

关键词： lattice QCD H-dibaryon spectral function clover fermion finite temperature