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Streamlined photonic reservoir computer with augmented memory capabilities 被引量:4
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作者 Changdi Zhou Yu Huang +5 位作者 Yigong Yang Deyu Cai Pei Zhou Kuenyao Lau Nianqiang li xiaofeng li 《Opto-Electronic Advances》 2025年第1期45-57,共13页
Photonic platforms are gradually emerging as a promising option to encounter the ever-growing demand for artificial intelligence,among which photonic time-delay reservoir computing(TDRC)is widely anticipated.While suc... Photonic platforms are gradually emerging as a promising option to encounter the ever-growing demand for artificial intelligence,among which photonic time-delay reservoir computing(TDRC)is widely anticipated.While such a computing paradigm can only employ a single photonic device as the nonlinear node for data processing,the performance highly relies on the fading memory provided by the delay feedback loop(FL),which sets a restriction on the extensibility of physical implementation,especially for highly integrated chips.Here,we present a simplified photonic scheme for more flexible parameter configurations leveraging the designed quasi-convolution coding(QC),which completely gets rid of the dependence on FL.Unlike delay-based TDRC,encoded data in QC-based RC(QRC)enables temporal feature extraction,facilitating augmented memory capabilities.Thus,our proposed QRC is enabled to deal with time-related tasks or sequential data without the implementation of FL.Furthermore,we can implement this hardware with a low-power,easily integrable vertical-cavity surface-emitting laser for high-performance parallel processing.We illustrate the concept validation through simulation and experimental comparison of QRC and TDRC,wherein the simpler-structured QRC outperforms across various benchmark tasks.Our results may underscore an auspicious solution for the hardware implementation of deep neural networks. 展开更多
关键词 photonic reservoir computing machine learning vertical-cavity surface-emitting laser quasi-convolution coding augmented memory capabilities
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Synthesis, characteristics of hierarchical EU-1 zeolite for xylene isomerization probe reaction 被引量:7
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作者 xiaofeng li Pengchao Ren +6 位作者 Yanting Zhang Xiaozhen liu Xiaotao Sun Meng Gao Miaojuan Jia Zhiping Lü Tao Dou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第11期1577-1583,共7页
Introduced a method of synthesizing hierarchical EU-1 zeolite with organosilanes as additive, and studied the influences of following different kinds of organosilanes on the synthesis of hierarchical EU-1 zeolite: γ-... Introduced a method of synthesizing hierarchical EU-1 zeolite with organosilanes as additive, and studied the influences of following different kinds of organosilanes on the synthesis of hierarchical EU-1 zeolite: γ-glycidoxy propyl trimethoxy silane(GPTMS), N-β-(aminoethyl)-γ-aminopropyl methyl dimethoxyl silane(APAEDMS),and N-(β-aminoethyl)-γ-aminopropyl dimethoxyl(ethyoxyl) silane(TMPED). The hierarchical EU-1 samples were characterized by XRD, SEM, N_2 adsorption, FT-IR and NH_3-TPD to analyze the crystallinity, morphology, surface area, pore size distribution and acidity. The results showed that hierarchical EU-1 zeolites were successfully synthesized; organosilanes have great influence on crystal morphology of EU-1 zeolites; the exterior surface area of hierarchical EU-1 zeolite, which synthesized with organosilanes(APAEDMS) adding into synthesis system, increased by 62.1% and mesopore volume increased by 129.1% compared with conventional EU-1 zeolites, thus can reduce the diffusional restriction markedly in catalytic reaction. The catalytic performance of hierarchical EU-1zeolites were evaluated in m-xylene isomerization on fixed bed reactor. The catalytic data showed that the isomerization activity PX/X of the hierarchical EU-1 zeolites reached around 24.09% in theoretical thermodynamic equilibrium from 23.83%, and the selectivity of C_8 aromatic hydrocarbon increased from 75.16% to 84.87%. The conversion of p-xylene increased from 16.30% to 18.41%. 展开更多
关键词 EU-1 Zeolite Hierarchical pore Synthesis Catalysis
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Effect of pre-autoclaving treatment on volume stability and compressive strength of carbonated magnesium slag
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作者 Xin Xu Jinhui liu +10 位作者 Yuandong Mu Yixin Zhang Yuming Zhao Peixu Yang Weidong Zhang xiaofeng li Yong Hu Weineng Tang Jiajia Tian Zhongtao Luo Shaojun Zhang 《Journal of Magnesium and Alloys》 2025年第11期5637-5651,共15页
The primary magnesium production is accompanied by a large amount of magnesium slag(MS)discharge.The low hydration reactivity of γ-Ca_(2)SiO_(4)(γ-C_(2)S)and MgO in MS results in the volume stability issue and low u... The primary magnesium production is accompanied by a large amount of magnesium slag(MS)discharge.The low hydration reactivity of γ-Ca_(2)SiO_(4)(γ-C_(2)S)and MgO in MS results in the volume stability issue and low utilization rate of MS.To eliminate the issue,this study proposes to pre-autoclave the MS slurry to boost the hydration of γ-C_(2)S and MgO and then utilize their hydration products to prepare cementitious materials by carbonation curing.MgO from MS and prepared γ-C_(2)S are firstly employed as study objects respectively,for they are the main contents of magnesium slag.The results indicate that pre-autoclaving treatment can strongly elevate the hydration degree of MgO from MS,this can substantially solve the volume stability issue of MS.Meanwhile,the pre-autoclaving of γ-C_(2)S induces the generation of crystallized and amorphous C-S-H products,and both products could promote the carbonation reaction when compared to γ-C_(2)S.The carbonation degree of pre-autoclaved MS firstly increases and then decreases with the rising pre-autoclaving temperature,and the optimal pre-autoclaving temperature for MS carbonation is 160℃,at this time,the powdered MS can be simply carbonated fully.The sample made of pre-autoclaved MS and then subjected to 4 h carbonation could achieve the compressive strength of 29 MPa.with good soundness.During volume stability testing,the volume expansion rate of a carbonated MS sample with pre-autoclaving was 0.07%,which is significantly lower than the normal requirement of 0.5%.This research offers a novel approach to utilizing magnesium slag in building materials and contributes to carbon reduction. 展开更多
关键词 Magnesium slag Volume stability Pre-autoclaving HYDRATION CARBONATION
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A major facilitator superfamily transporter PlMFS1 contributes to growth,oosporogenesis,and pathogenesis of Peronophythora litchii
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作者 Pinggen Xi Tianfang Guan +9 位作者 Xiyuan liu xiaofeng li Ziyuan Dou liyun Shi Jiamin Huang liqun Jiang Junjian Situ Minhui li Guanghui Kong Zide Jiang 《Horticultural Plant Journal》 2025年第1期189-198,共10页
Major facilitator superfamily(MFS)transporters are secondary active membrane transporters that play an important role in solute interchange and energy metabolism.Peronophythora litchii causes the most destructive dise... Major facilitator superfamily(MFS)transporters are secondary active membrane transporters that play an important role in solute interchange and energy metabolism.Peronophythora litchii causes the most destructive disease on lichi,litchi downy blight.PlM90 was reported as a key oosporogenesis regulator.Here,we identified an MFS transporter gene PlMFS1,which is up-regulated during oospore formation at the late infection stage,while down-regulated in the PlM90 mutant.To investigate PlMFS1 function,we generated PlMFS1knockout mutants using CRISPR/Cas9-mediated genome editing technology.Compared with the wild-type strain SHS3,PlMFS1 deletion impaired mycelium growth,zoospore release,oospore production and pathogenicity.Furthermore,PlMFS1 deletion significantly affected P.litchii utilization of fructose,lactose and maltose,and may be the PlMFS1 mechanism involved in mycelial growth.PlMFS1 gene deletion also led to deceased laccase activity,laccase-encoding gene downregulation and impaired P.litchii pathogenicity.To our knowledge,this is the first report of an MFS transporter involved in sugar utilization,sexual reproduction,asexual reproduction and pathogenesis in oomycetes. 展开更多
关键词 Peronophythora litchii Major facilitator superfamily OOSPORE PATHOGENICITY
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Data-Based Optimal Tracking of Autonomous Nonlinear Switching Systems 被引量:3
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作者 xiaofeng li Lu Dong Changyin Sun 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第1期227-238,共12页
In this paper,a data-based scheme is proposed to solve the optimal tracking problem of autonomous nonlinear switching systems.The system state is forced to track the reference signal by minimizing the performance func... In this paper,a data-based scheme is proposed to solve the optimal tracking problem of autonomous nonlinear switching systems.The system state is forced to track the reference signal by minimizing the performance function.First,the problem is transformed to solve the corresponding Bellman optimality equation in terms of the Q-function(also named as action value function).Then,an iterative algorithm based on adaptive dynamic programming(ADP)is developed to find the optimal solution which is totally based on sampled data.The linear-in-parameter(LIP)neural network is taken as the value function approximator.Considering the presence of approximation error at each iteration step,the generated approximated value function sequence is proved to be boundedness around the exact optimal solution under some verifiable assumptions.Moreover,the effect that the learning process will be terminated after a finite number of iterations is investigated in this paper.A sufficient condition for asymptotically stability of the tracking error is derived.Finally,the effectiveness of the algorithm is demonstrated with three simulation examples. 展开更多
关键词 Adaptive dynamic programming approximation error data-based control Q-LEARNING switching system
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Peak-like three-dimensional CoFe_(2)O_(4)/carbon nanotube decorated bamboo fabrics for simultaneous solar-thermal evaporation of water and photocatalytic degradation of bisphenol A 被引量:2
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作者 Rui-Jie Pan Jing Wu +6 位作者 Jin Qu Tingting Zhang Fan-Zhen Jiao Mang Zhao Meng-Yan Han xiaofeng li Zhong-Zhen Yu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第12期40-49,共10页
Catalytic CoFe_(2)O_(4) and solar-thermal carbon nanotube decorated bamboo fabrics(CCBF)are fabricated for integrating efficient solar steam generation from wastewater with catalytic degradation of its organic con-tam... Catalytic CoFe_(2)O_(4) and solar-thermal carbon nanotube decorated bamboo fabrics(CCBF)are fabricated for integrating efficient solar steam generation from wastewater with catalytic degradation of its organic con-taminants.Thanks to the numerous porous channels and polar groups of bamboo fabric and the efficient solar-thermal energy conversion of black carbon nanotubes,the porous and hydrophilic CCBF exhibits fast upward transport of water,efficient solar light absorption,and high solar-thermal energy conversion effi-ciency.The decorated CoFe_(2)O_(4) not only enhances the solar-thermal energy conversion efficiency of CCBF but also activates potassium peroxymonosulfate to generate abundant highly active species for catalytic degradation of bisphenol A(BPA).Furthermore,folding the CCBF into a peak-like 3D evaporator can en-hance solar energy utilization,and gain environmental energy for promoting solar-thermal water evapo-ration and catalytic degradation performances.The 3D CCBF evaporator achieves a water evaporation rate of 2.72 kg m^(-2) h^(-1) under 1-sun irradiation.Meanwhile,100%of the BPA in the seawater can be degraded within 10 min.An exceptional high purification efficiency of 27.72 kg m^(-2) h^(-1) is achieved with the 3D evaporator during a long-term treatment of BPA-containing seawater under 1-sun irradiation.This work demonstrates efficient purification of seawater/wastewater with both metal ions and organic pollutants by simultaneous solar-thermal evaporation of water and catalytic degradation of organic pollutants. 展开更多
关键词 Solar-thermal water evaporation Seawater desalination Catalytic degradation Carbon nanotubes CoFe_(2)O_(4)
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Preclinical and clinical applications of specific molecular imaging for HER2-positive breast cancer 被引量:2
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作者 Wei Chen xiaofeng li +3 位作者 Lei Zhu Jianjing liu Wengui Xu Ping Wang 《Cancer Biology & Medicine》 SCIE CAS CSCD 2017年第3期271-280,共10页
Precision medicine and personalized therapy are receiving increased attention, and molecular-subtype classification has become crucial in planning therapeutic schedules in clinical practice for patients with breast ca... Precision medicine and personalized therapy are receiving increased attention, and molecular-subtype classification has become crucial in planning therapeutic schedules in clinical practice for patients with breast cancer. Human epidermal growth factor receptor 2(HER2) is associated with high-grade breast tumors, high rates of lymph-node involvement, high risk of recurrence, and high resistance to general chemotherapy. Analysis of HER2 expression is highly important for doctors to identify patients who can benefit from trastuzumab therapy and monitor the response and efficacy of treatment. In recent years, significant efforts have been devoted to achieving specific and noninvasive HER2-positive breast cancer imaging in vivo. In this work, we reviewed existing literature on HER2 imaging in the past decade and summarized the studies from different points of view, such as imaging modalities and HER2-specific probes. We aimed to improve the understanding on the translational process in molecular imaging for HER2 breast cancer. 展开更多
关键词 Breast cancer human epidermal growth factor receptor 2(HER2) molecular imaging probes
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Mineral Chemistry of Biotite and Its Petrogenesis Implications in ca.2.5 Ga Wangjiazhuang Granitic Pluton,North China Craton 被引量:1
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作者 Junpeng Wang Kang Jiang +5 位作者 Deng Xiao Fenfang li Fupeng li xiaofeng li Song Jin Guanghuo Tao 《Journal of Earth Science》 SCIE CAS CSCD 2022年第6期1535-1548,共14页
The Wangjiazhuang granitic pluton is located in the central Zanhuang Domain,the central part of the North China Craton,which is mainly composed of biotite monzogranite with few mafic microgranular enclaves.Biotite is ... The Wangjiazhuang granitic pluton is located in the central Zanhuang Domain,the central part of the North China Craton,which is mainly composed of biotite monzogranite with few mafic microgranular enclaves.Biotite is an important ferromagnesian mineral in most of the intermediatefelsic igneous rocks,and its mineral chemistry can record the properties of magma and the petrogenetic physicochemical conditions.In this study,we carried out a detailed petrographic study by electric probe microanalysis on biotite for the biotite monzogranite and mafic microgranular enclaves,to discuss the source,physicochemical conditions,and the magma mingling/mixing processes of the Wangjiazhuang granite.The results show significantly different chemical compositions from the biotite monzogranite and mafic microgranular enclaves.The crystallization of these biotite grains from the biotite monzogranite and mafic microgranular enclaves all occurred in low oxygen fugacity.The biotite grains in biotite monzogranite are rich in Fe,poor in Mg,which belong to siderophyllite.The ratios of[(Fe^(3+)+Fe^(2+))/(Fe^(3+)+Fe^(2+)+Mg2+)]are between 0.78 and 0.86.The average of FeOT(total FeO)/MgO of biotite grains in biotite monzogranite is 9.02.The MF values[2×Mg/(Fe^(2+)+Mg+Mn)]of biotite monzogranite are between 0.31 and 0.47,suggesting biotite monzogranite derived from crustal source rocks(metasedimentary rocks).The formation of granitic rocks including the Wangjiazhuang granite was related to the subduction event at ca.2.5 Ga which resulted in the melting event,and then induced the early partial melting of TTGs and metasedimentary rocks.The biotite in mafic microgranular enclaves varies from siderophyllite to ferrobiotite,and MF values range from 0.63 to 1.06,suggesting that magma of mafic microgranular enclaves had experienced magma mixing/mingling in various degrees.Biotite monzogranite and parts of mafic microgranular enclaves have a similar crystallized condition,while other mafic microgranular enclaves are different from biotite monzogranite.The differences between biotite monzogranite and mafic microgranular enclaves may be a consequence of continuous interaction between granitic and mafic magmas. 展开更多
关键词 BIOTITE mineral chemistry CRYSTALLIZATION magma mixing Wangjiazhuang granite Zanhuang Massif North China Craton
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Development of a new index for automated mapping of ratoon rice areas using time-series normalized difference vegetation index imagery 被引量:1
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作者 Bolun li Shaobing PENG +6 位作者 Runping SHEN Zong-liang YANG Xiaoyuan YAN xiaofeng li Rongrong li Chengye li Guangbin ZHANG 《Pedosphere》 SCIE CAS CSCD 2022年第4期576-587,共12页
Over recent decades, the global demand for food has continued to grow, owing to population growth and the loss of arable land. Rice ratooning offers new opportunities for increasing rice production and has received re... Over recent decades, the global demand for food has continued to grow, owing to population growth and the loss of arable land. Rice ratooning offers new opportunities for increasing rice production and has received renewed interest because of the minimal additional labor input required for its adoption. Regular, regional-scale monitoring of the spatial patterns of both traditional and ratoon rice cropping systems provides essential information for agricultural resource management and food security studies. However, the similar phenological characteristics of traditional double rice and ratoon rice cropping systems make it challenging to accurately classify these cropping practices based on satellite observations alone. In this study, we first proposed an improved phenology-based rice cropping area detection algorithm using moderate resolution imaging spectroradiometer (MODIS) normalized difference vegetation index (NDVI) imagery. A new index, ratoon rice index, was then developed to automatically delineate ratoon rice cropping areas with the aid of a base map of rice in Hubei Province, China. The accuracy assessment using ground truth data showed that our approach could map both traditional and ratoon rice cropping areas with high user accuracy (91.25% and 91.43%, respectively). The MODIS-retrieved rice cropping areas were validated using annual agricultural census data, and coefficient of determination (R2) values of 0.60 and 0.41 were recorded for traditional and ratoon rice cropping systems, respectively. The total area of ratoon rice was estimated to be 1 283.6 km2, 5.0% of the total rice cropping area, in Hubei Province in 2016. These demonstrated the feasibility of extracting the spatial patterns of both traditional and ratoon rice cropping systems solely from time-series NDVI and field survey data and strides made in facilitating the timely and routine monitoring of traditional and ratoon rice distribution at subnational level. Given sufficient historical satellite and phenology records, the proposed algorithm had the potential to enhance rice cropping area mapping efforts across a broad temporal scale (e.g., from the 1980s to the present). 展开更多
关键词 cropping area estimationcross correlogram moderate resolution imaging spectroradiometer(MODIS) ratoon rice index spectral matching
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Simultaneous Functionalization and Reduction of Graphene Oxide with Polyetheramine and Its Electrically Conductive Epoxy Nanocomposites 被引量:1
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作者 Gongqing Tang Zhi-Guo Jiang +2 位作者 xiaofeng li 张好斌 于中振 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2014年第8期975-985,共11页
Simultaneous functionalization and reduction of graphene oxide (GO) is realized by refluxing of GO suspension with polyetheramine (D2000) followed by thermal treatment at 120℃. Compared to GO, the D2000-treated ... Simultaneous functionalization and reduction of graphene oxide (GO) is realized by refluxing of GO suspension with polyetheramine (D2000) followed by thermal treatment at 120℃. Compared to GO, the D2000-treated GO (GO- D2000) becomes hydrophobic, thermally stable and highly conductive with an electrical conductivity of 11 S/m, which is almost 8 orders of magnitude higher than that of GO. Due to the high conductivity and improved dispersion of GO-D2000, its epoxy nanocomposites exhibit a sharp transition from electrically insulating to conducting with a low percolation threshold of 0.71 vol%. With 3.6 wt% GO-D2000, the glass transition temperature of the epoxy nanocomposite is 27 K higher than that of neat epoxy. 展开更多
关键词 Graphene oxide EPOXY Chemical reduction Electrical conductivity Glass transition temperature.
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Value of metabolic parameters in distinguishing primary mediastinal lymphomas from thymic epithelial tumors 被引量:1
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作者 Lei Zhu xiaofeng li +5 位作者 Jian Wang Qiang Fu Jianjing liu Wenchao Ma Wengui Xu Wei Chen 《Cancer Biology & Medicine》 SCIE CAS CSCD 2020年第2期468-477,共10页
Objective:A high rate of unnecessary thymectomies has been reported.This study aimed to distinguish primary mediastinal lymphomas(PMLs)from thymic epithelial tumors(TETs)by evaluating volumetric and metabolic paramete... Objective:A high rate of unnecessary thymectomies has been reported.This study aimed to distinguish primary mediastinal lymphomas(PMLs)from thymic epithelial tumors(TETs)by evaluating volumetric and metabolic parameters with l8F-FDG PET/CT.Methods:A total of 136 patients who were pathologically diagnosed with TETs or PMLs were enrolled,and 18F-FDG PET/CT was performed before therapy.Volumetric parameters,including the mean SUV(SUVmean),metabolic tumor volume(MTV),total lesion glycolysis(TLG),and SUVmax,were determined and compared between the 2 subtypes.The diagnostic performance of these parameters was evaluated with receiver operating characteristic(ROC)curve analysis.Results:All parameters significantly differed between patients with PMLs and TETs.Patients with lymphomas were younger and had higher SUVmean,SUVmax,TLG,and MTV values than patients with TETs.The MTV and TLG values had similar diagnostic performance.ROC analysis indicated that the areas under the curves of the SUVmean and SUVmax values performed similarly(approximately 0.76)in differentiating patients with PMLs from TETs,and both values were better than the MTV and TLG values.When age was included with the SUVmax in differentiating TETs from PMLs,the AUC was 0.91,and the sensitivity and specificity increased to 80%and 93%,respectively.Conclusions:The SUVmax and volumetric parameters of 18F-FDG PET/CT can be used to distinguish patients with PMLs versus TETs,and thus may aid in preventing unnecessary thymectomies or other invasive operations. 展开更多
关键词 FDG PET-CT LYMPHOMA metabolic tumor burden quantitative evaluation thymic epithelial tumors
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Deep learning in extracting tropical cyclone intensity and wind radius information from satellite infrared images—A review 被引量:1
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作者 Chong Wang xiaofeng li 《Atmospheric and Oceanic Science Letters》 CSCD 2023年第4期65-71,共7页
热带气旋(TC)严重危害人类生命和财产安全,TC的实时监测一直是研究热点,随着空间和传感器技术的发展,卫星遥感已成为监测TC的主要手段.此外,深度学习具有卓越的数据挖掘能力,在地球科学中的表现优于基于物理或统计的算法,越来越多的深... 热带气旋(TC)严重危害人类生命和财产安全,TC的实时监测一直是研究热点,随着空间和传感器技术的发展,卫星遥感已成为监测TC的主要手段.此外,深度学习具有卓越的数据挖掘能力,在地球科学中的表现优于基于物理或统计的算法,越来越多的深度学习算法被开发和应用于TC信息的提取,本文系统地回顾了深度学习在TC信息提取中的应用,并给出了深度学习模型在TC强度和风圈半径提取中的应用.此外,本文还展望了深度学习在TC信息提取中的应用前景. 展开更多
关键词 热带气旋 深度学习 遥感 信息提取
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Unveiling three-dimensional sea surface signatures caused by internal solitary waves:insights from the surface water ocean topography mission 被引量:1
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作者 Xudong ZHANG xiaofeng li 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期709-714,共6页
Internal solitary waves(ISW),characterized by large amplitude and long propagation distance,are widespread in global oceans.While remote sensing images have played an essential role in studying ISWs,they mainly exploi... Internal solitary waves(ISW),characterized by large amplitude and long propagation distance,are widespread in global oceans.While remote sensing images have played an essential role in studying ISWs,they mainly exploit two-dimensional image information.However,with the launch of the surface water ocean topography(SWOT)satellite on December 16,2022,a unique opportunity has emerged to capture wide-swath three-dimensional ISW-induced sea surface information.In this study,we examine ISWs in the Andaman Sea using data from the Ka-band Radar Interferometer(KaRIN),a crucial sensor onboard SWOT.KaRIN not only provides backscattering satellite images but also employs synthetic aperture interferometry techniques to retrieve wide-swath two-dimensional sea surface height measurements.Our observations in the Andaman Sea revealed the presence of ISWs characterized by dark-bright strips and surface elevation solitons.The surface soliton has an amplitude of 0.32 m,resulting in an estimation of ISW amplitude of approximately 60 m.In contrast to traditional two-dimensional satellite images or nadir-looking altimetry data,the SWOT mission’s capability to capture threedimensional sea surface information represents a significant advancement.This breakthrough holds substantial promise for ISW studies,particularly in the context of ISW amplitude inversion. 展开更多
关键词 internal solitary wave(ISW) surface water ocean topography(SWOT) ALTIMETER
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Single-atom rhodium anchored on S-doped black phosphorene as a promising bifunctional electrocatalyst for overall water splitting
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作者 Xinyi li Zhongxu Wang +3 位作者 Yu Tian xiaofeng li Qinghai Cai Jingxiang Zhao 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第7期269-273,共5页
Superior bifunctional electrocatalysts with ultra-high stability and excellent efficiency are crucial to boost the oxygen evolution reaction(OER) and the hydrogen evolution reduction(HER) in the overall water splittin... Superior bifunctional electrocatalysts with ultra-high stability and excellent efficiency are crucial to boost the oxygen evolution reaction(OER) and the hydrogen evolution reduction(HER) in the overall water splitting(OWS) for the sustainable production of clean fuels. Herein, comprehensive density functional theory(DFT) computations were performed to explore the potential of several single transition metal(TM) atoms anchored on various S-doped black phosphorenes(TM/Snx-BP) for bifunctional OWS electrocatalysis. The results revealed that these candidates display good stability, excellent electrical conductivity, and diverse spin moments. Furthermore, the Rh/S12-BP catalyst was identified as an eligible bifunctional catalyst for OWS process due to the low overpotentials for OER(0.43 V) and HER(0.02 V), in which Rh and its adjacent P atoms were identified as the active sites. Based on the computed Gibbs free energies of OH~*, O~*, OOH~* and H~*, the corresponding volcano plots for OER and HER were established.Interestingly, the spin moments and the charge distribution of the active sites determine the catalytic trends of OER and HER. Our findings not only propose a promising bifunctional catalyst for OWS, but also widen the potential application of BP in electrocatalysis. 展开更多
关键词 Overall water splitting Bifunctional catalysts Single-atom catalysts S-doped black phosphorene Density functional theory computations
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Manganese toxicity-induced chlorosis in sugarcane seedlings involves inhibition of chlorophyll biosynthesis
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作者 Shu Yang Guizhi ling +4 位作者 Qiuyue li Ke Yi Xinlian Tang Muqing Zhang xiaofeng li 《The Crop Journal》 SCIE CSCD 2022年第6期1674-1682,共9页
Manganese(Mn)toxicity-induced leaf chlorosis limits crop production in acidic soils,but its underlying mechanisms remain unknown.The effects of excessive Mn on chlorophyll(Chl)biosynthesis in sugarcane(Saccharum offic... Manganese(Mn)toxicity-induced leaf chlorosis limits crop production in acidic soils,but its underlying mechanisms remain unknown.The effects of excessive Mn on chlorophyll(Chl)biosynthesis in sugarcane(Saccharum officinarum L.)leaves were investigated.Under Mn treatment,Chl concentration decreased with Mn accumulation and chlorosis appeared in expanding leaves.Before that,levels of the initial Chl precursor 5-aminolevulinic acid(ALA)and its downstream intermediates decreased,whereas magnesium-protoporphyrin IX monomethyl ester(MgPME)accumulated.Overaccumulation of Mn in leaves downregulated the ALA biosynthetic gene GluTR(encoding glutamyl-tRNA reductase)and MgPME conversion gene MgPMEC(encoding MgPME cyclase),upregulated the ALA biosynthesis inhibitor FLU(encoding FLUORESCENT),but had no significant effect on the expression of other Chl biosynthetic genes.The above Mn-induced changes of Chl precursors and expression of corresponding genes commenced before the Chl decline and leaf chlorosis,and were reversed by ALA supplementation.Thus,excessive Mn-induced chlorosis in sugarcane is mediated by a Chl-biosynthesis disorder resulting from the inhibition of ALA synthesis and MgPME conversion. 展开更多
关键词 SUGARCANE Manganese toxicity CHLOROSIS Chlorophyll biosynthesis Gene expression
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Effective regulation of the interaction process among three optical solitons
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作者 Houhui Yi xiaofeng li +2 位作者 Junling Zhang Xin Zhang Guoli Ma 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期190-197,共8页
The interaction between three optical solitons is a complex and valuable research direction,which is of practical application for promoting the development of optical communication and all-optical information processi... The interaction between three optical solitons is a complex and valuable research direction,which is of practical application for promoting the development of optical communication and all-optical information processing technology.In this paper,we start from the study of the variable-coefficient coupled higher-order nonlinear Schodinger equation(VCHNLSE),and obtain an analytical three-soliton solution of this equation.Based on the obtained solution,the interaction of the three optical solitons is explored when they are incident from different initial velocities and phases.When the higher-order dispersion and nonlinear functions are sinusoidal,hyperbolic secant,and hyperbolic tangent functions,the transmission properties of three optical solitons before and after interactions are discussed.Besides,this paper achieves effective regulation of amplitude and velocity of optical solitons as well as of the local state of interaction process,and interaction-free transmission of the three optical solitons is obtained with a small spacing.The relevant conclusions of the paper are of great significance in promoting the development of high-speed and large-capacity optical communication,optical signal processing,and optical computing. 展开更多
关键词 optical solitons solitons interactions nonlinear Schr¨odinger equation higher-order dispersion and nonlinear effects
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FPSblo:A Blockchain Network Transmission Model Utilizing Farthest Point Sampling
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作者 Longle Cheng Xiru li +4 位作者 Shiyu Fang Wansu Pan He Zhao Haibo Tan xiaofeng li 《Computers, Materials & Continua》 SCIE EI 2024年第2期2491-2509,共19页
Peer-to-peer(P2P)overlay networks provide message transmission capabilities for blockchain systems.Improving data transmission efficiency in P2P networks can greatly enhance the performance of blockchain systems.Howev... Peer-to-peer(P2P)overlay networks provide message transmission capabilities for blockchain systems.Improving data transmission efficiency in P2P networks can greatly enhance the performance of blockchain systems.However,traditional blockchain P2P networks face a common challenge where there is often a mismatch between the upper-layer traffic requirements and the underlying physical network topology.This mismatch results in redundant data transmission and inefficient routing,severely constraining the scalability of blockchain systems.To address these pressing issues,we propose FPSblo,an efficient transmission method for blockchain networks.Our inspiration for FPSblo stems from the Farthest Point Sampling(FPS)algorithm,a well-established technique widely utilized in point cloud image processing.In this work,we analogize blockchain nodes to points in a point cloud image and select a representative set of nodes to prioritize message forwarding so that messages reach the network edge quickly and are evenly distributed.Moreover,we compare our model with the Kadcast transmission model,which is a classic improvement model for blockchain P2P transmission networks,the experimental findings show that the FPSblo model reduces 34.8%of transmission redundancy and reduces the overload rate by 37.6%.By conducting experimental analysis,the FPS-BT model enhances the transmission capabilities of the P2P network in blockchain. 展开更多
关键词 Blockchain P2P networks SCALABILITY farthest point sampling
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Higher-Order Nonlinear Effects on Optical Soliton Propagation and Their Interactions
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作者 伊厚会 李晓凤 +2 位作者 张俊玲 张鑫 马国利 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第7期53-57,共5页
When pursuing femtosecond-scale ultrashort pulse optical communication, one cannot overlook higher-order nonlinear effects. Based on the fundamental theoretical model of the variable coefficient coupled high-order non... When pursuing femtosecond-scale ultrashort pulse optical communication, one cannot overlook higher-order nonlinear effects. Based on the fundamental theoretical model of the variable coefficient coupled high-order nonlinear Schr¨odinger equation, we analytically explore the evolution of optical solitons in the presence of highorder nonlinear effects. Moreover, the interactions between two nearby optical solitons and their transmission in a nonuniform fiber are investigated. The stability of optical soliton transmission and interactions are found to be destroyed to varying degrees due to higher-order nonlinear effects. The outcomes may offer some theoretical references for achieving ultra-high energy optical solitons in the future. 展开更多
关键词 NONLINEAR SOLITONS SOLITON
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Modification and sequential treatment of EU-1 zeolite in mild alkali and alkaline-acid conditions
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作者 xiaofeng li Xiaotao Sun +4 位作者 Yanting Zhang Junliang Zhang Pengchao Ren Xiaozhen liu Tao Dou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第12期1728-1734,共7页
EU-1 zeolites were sequentially treated with low-concentration sodium carbonate(Na_2CO_3) and hydrochloric acid(HCl) solutions.The obtained samples were characterized by X-ray diffraction(XRD),scanning electron micros... EU-1 zeolites were sequentially treated with low-concentration sodium carbonate(Na_2CO_3) and hydrochloric acid(HCl) solutions.The obtained samples were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),N_2 adsorption/desorption,temperature programmed desorption of NH_3(NH_3-TPD),solid state^(27)A1 nuclear magnetic resonance(^(27)A1 NMR),and the catalytic performances of the treated samples were tested in the xylene isomerization reaction.The results showed that the external surface area and mesoporous volume of the sample sequentially treated with 0.05 mol·L^(-1) Na_2CO_3 and 0.1 mol·L^(-1) HCl solutions reached73.9 m^2·g^(-1) and 0.162 cm^3·g^(-1),respectively.The catalytic performances of EU-1 zeolites were significantly improved,that the activity of the probe reaction increased from 23.03%to 23.61%and the selectivity increased from85.09%to 87.14%compared with those of parent sample.Furthermore,it was found that only amorphous silica and alumina species was dissolved during the post-treatment process,but the framework structure and the acidic properties of EU-1 zeolite remained intact. 展开更多
关键词 EU-1 zeolite Mesoporous Catalysis
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Evaluation Model of Teaching Quality Based on Cloud Computing
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作者 xiaofeng li Qiushi Wang 《国际计算机前沿大会会议论文集》 2019年第2期415-416,共2页
In the teaching quality evaluation, due to the influence of various human factors, the teaching quality evaluation system is presented with some grey characteristics. Traditional evaluation methods cannot solve the pr... In the teaching quality evaluation, due to the influence of various human factors, the teaching quality evaluation system is presented with some grey characteristics. Traditional evaluation methods cannot solve the problem effectively. Through gray relational analysis, the grey system of partial information known and unknown can be analyzed. It is difficult for the qualitative description language evaluation index to use traditional mathematical model for accurate representation. In this paper, cloud model is combined with grey relational analysis, and an evaluation method is proposed based on the cloudgrey relational analysis, in order to realize the mutual transformation between the qualitative information and quantitative numerical. Three university teachers’ information was collected by questionnaire survey, and the teaching quality was evaluated through the evaluation model based on grey relational analysis built in MATLAB. The results were compared with those of fuzzy comprehensive evaluation and the BP neural network evaluation. The results show that the teaching quality evaluation model based on cloud grey relational analysis has certain rationality and feasibility. 展开更多
关键词 CLOUD model TEACHING QUALITY GRAY RELATIONAL analysis
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