检索结果-南通市图书馆

Combining anodic alcohol oxidative coupling for C-C bond formation with cathodic ammonia production

National Science Review 2024年第5期11卷 217-226页

作者： Leitao Xu Wei Chen Cairong Wang Wenjie Wu Yelin Yao Zhifeng Huang Jingcheng Wu Ming Yang Yandong Wu Dianke Xie Yuqin Zou Shuangyin Wang State Key Laboratory of Chemo/Bio-sensing and Chemometrics College of Chemistry and Chemical EngineeringAdvanced Catalytic Engineering Research Center of the Ministry of Education Hunan University

Electrocatalytic oxidation of alcohols using heterogeneous catalysts is a promising aqueous, energy-efficient and environmentally friendly approach, especially for coupling different alcohols to prolong the carbon chain via co-oxidation. Precisely regulating critical steps to tailor electrode materials and electrolyte composition is key to selectively coupling alcohols for targeted synthesis. However, selectively coupling different alcohols remains challenging due to the lack of effective catalyst and electrolyte design promoting specific pathways. Herein, we demonstrate a paired electrolysis strategy for combining anodic oxidative coupling of ethanol（EtOH） and benzyl alcohol（PhCH2OH） to synthesize cinnamaldehyde（CAL） and cathodic ammonia production. The strategies involve:（i） utilizing the salt-out effect to balance selective oxidation and coupling rates;（ii） developing platinum-loaded nickel hydroxide electrocatalysts to accelerate intermediate coupling kinetics;（iii） introducing thermodynamically favorable nitrate reduction at the cathode to improve coupling selectivity by avoiding hydrogenation of products while generating valuable ammonia instead of hydrogen. We achieved 85% coupling selectivity and 278 μmol/h NH3productive rate at 100 m A/cm2with a low energy input（～1.63 V）. The membrane-free, low energy, scalable approach with a wide substrate scope highlights promising applications of this methodology. This work advances heterogeneous electrocatalytic synthesis through rational design principles that integrate anodic oxidative coupling with cathodic nitrate reduction reactions, having synergistic effects on efficiency and selectivity.

关键词： anodic alcohol oxidative coupling C–C bond formation cinnamaldehyde cathodic ammonia production

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Super-resolution Imaging of Telescopic Systems based on Optical-neural Network Joint Optimization

引用

research in Astronomy and Astrophysics 2024年第9期24卷 167-177页

作者： You-Hong Sun Tao Zhang Hao-Dong Shi Qiang Fu Jia-Nan Liu Kai-Kai Wang Chao Wang research Institute of Chongqing Changchun University of Science and TechnologyChangchun 130022China National and Local Joint Engineering research center for Space Photoelectric Technology Changchun University of Science and TechnologyChangchun 130022China The Institute of remote sensing Satellites China Academy of Space Technology(CAST)Beijing 100094China

Optical telescopes are an important tool for acquiring optical information about distant objects,and resolution is an important indicator that measures the ability to observe object ***,due to the effects of system aberration,atmospheric seeing,and other factors,the observed image of ground-based telescopes is often degraded,resulting in reduced *** paper proposes an optical-neural network joint optimization method to improve the resolution of the observed image by co-optimizing the point-spread function(PSF)of the telescopic system and the image super-resolution(SR)*** improve the speed of image reconstruction,we designed a generative adversarial net(LCR-GAN)with light parameters,which is much faster than the latest unsupervised *** reconstruct the PSF trained by the network in the optical path,a phase mask is *** improves the image reconstruction effect of LCR-GAN by reconstructing the PSF that best matches the *** results of simulation and verification experiments show that compared with the pure deep learning method,the SR image reconstructed by this method is rich in detail and it is easier to distinguish stars or stripes.

关键词： Techniques:image processing Telescopes Stars:imaging

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

Controllable split polarization singularities for ultra-precise displacement sensing

引用

Photonics research 2024年第7期12卷 1478-1484页

作者： JIAKANG ZHOU HAIXIANG MA SHUOSHUO ZHANG WU YUAN CHANGJUN MIN XIAOCONG YUAN YUQUAN ZHANG Nanophotonics research Centre Institute of Microscale Optoelectronics&State Key Laboratory of Radio Frequency Heterogeneous IntegrationShenzhen UniversityShenzhen 518060China research center for Humanoid sensing Research Institute of Intelligent SensingZhejiang LabHangzhou 311100China Department of Biomedical Engineering The Chinese University of Hong KongHong KongChina

The topic of optical precise displacement measurement has garnered significant attention and generated widespread interest recently. The use of optical singularity offers a potential solution for this purpose, although effectively manipulating the singularity in an ideal manner remains challenging. In this work, we propose a theoretical approach to achieve controllable position modulation of the C-point in the focal plane, whose spatial position can be easily modulated by adjusting the relative offset factor β and the offset angle α of an azimuthal polarization beam(APB), while the interval and orientation of the C-points can be flexibly regulated. Notably, the chiral polarization state undergoes a distinct reversal along the link-line connecting the two C-points, thereby providing a promising approach for accurate displacement sensing. To evaluate its sensing characteristics, the varying pattern of the scattered field intensity is monitored when sweeping a gold helix and nanoparticle along the link-line. The results of simulation quality index Q verify that the equilibrium factor of the scattering field possesses an obvious linear relationship with the displacement, signifying a precise sub-nanometric *** research introduces new methods for the flexible control of polarization singularities in tightly focused fields,thereby enhancing the utilization of circular polarization properties near C-points for displacement *** findings not only enrich the field of nanometer measurement technology but also pave the way for new avenues of research in this domain.

关键词： polarization displacement precise

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

Spectral matching based remote sensing identification of two main crop rotation patterns in a large irrigation district

引用

中国水利水电科学研究院学报(中英文) 2024年

作者： DUAN Yuanyuan CHEN Xiuhua LIU Jun YE Mao LU Wenjing LIU Hongjie China Institute of Water Resources and Hydropower research Application center of remote sensing Technology Research Center on Flood & Drought Disaster Prevention and Reduction of the Ministry of Water Resources Qingdao Comcore Technologies Co. Ltd Sucheng District Water Resources Bureau

Abstract:The rapid identification of planting patterns for major crops in a large irrigated district has vital importance for irrigation management,water fee collection,and crop yield *** this study,the OTSU algorithm and Mean-Shift algorithm were employed to automatically determine threshold values for mapping two main rotated crop patterns at the pixel scale.A time series analysis was conducted to extract the spatial distribution of rice-wheat and wheat-maize rotations in the Chuanhang irrigation district from 2016 to *** results demonstrate that both threshold segmentation algorithms are reliable in extracting the spatial distribution of the crops,with an overall accuracy exceeding 80%.Additionally,both Kappa coefficients surpass 0.7,indicating better performance by OTSU *** the period from 2016 to 2020,the area occupied by ricewheat rotation cropping ranged from 12 500 to 14 400 hm2;whereas wheat-maize rotation cropping exhibited smaller and more variable areas ranging from 19730 to 34070 *** findings highlight how remote sensing-based approaches can provide reliable support for rapidly and accurately identifying the spatial distribution of main crop rotation patterns within a large irrigation district.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

“以膜制膜”:三维聚吡咯纳米管阵列薄膜及其应用

引用

Science China Materials 2024年第4期67卷 1310-1319页

作者：陈盼盼尚薛杭天 center for Scientific Facilities Development and Management Research Center for Intelligent Sensing SystemsResearch Institute of Intelligent SensingZhejiang LabHangzhou 311121China

导电聚合物具有良好的导电性和化学稳定性等优异特性,在各种应用领域被广泛研究.三维导电聚合物具有相互连接的网络结构,可提供超高比表面积,是极具潜力的高性能材料结构.尽管纳米制造技术已取得飞速进展,但制备有序导电聚合物超结构,... 详细信息

导电聚合物具有良好的导电性和化学稳定性等优异特性,在各种应用领域被广泛研究.三维导电聚合物具有相互连接的网络结构,可提供超高比表面积,是极具潜力的高性能材料结构.尽管纳米制造技术已取得飞速进展,但制备有序导电聚合物超结构,如有序排列的纳米通道,仍极具挑战性.本研究提出了一种简便高效的模板合成法,可制备三维聚吡咯膜结构.以柔性径迹蚀刻聚碳酸酯膜为模板,通过化学聚合法,经去除模板即可获得具有垂直排列通道和连续连接层的三维纳米管阵列薄膜.膜结构中纳米通道长度、直径等微结构尺寸均可精细调控.这种“以膜制膜”的方法具通用性、成本低等特点.进一步,我们证明了该精密膜结构在毒害离子吸附、太阳能光热转换、毒害气体传感等方面应用的可能.该结构对六价铬离子表现出快速、优异的吸附性能;无需额外表面改性和基底结构辅助,可直接应用为界面太阳能光热转换材料;对毒害气体氨气展现出优异的传感响应.该工作不仅为聚比咯精细膜结构的制备提供了一种可行的方法,也极大地拓展了三维导电聚合物材料的应用.

关键词：导电聚合物纳米通道六价铬离子聚碳酸酯膜高性能材料膜结构有序排列垂直排列

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

Imaging a force field via an optically levitated nanoparticle array

引用

Chinese Physics B 2024年第9期33卷 179-184页

作者： Bihu Lv Jiandong Zhang Chuang Li research center for Novel Computing sensing and Intelligent Processing Zhejiang LaboratoryHangzhou 311121China School of Mathematics and Physics Jiangsu University of TechnologyChangzhou 213001China

Levitated optomechanical systems represent an excellent candidate platform for force and acceleration *** propose a force-sensing protocol utilizing an optically levitated nanoparticle *** our scheme,N nanoparticles are trapped in an optical cavity using holographic optical *** external laser drives the cavity,exciting N cavity modes interacting simultaneously with the N *** optomechanical interaction encodes the information of the force acting on each nanoparticle onto the intracavity photons,which can be detected directly at the output ports of the ***,our protocol enables real-time imaging of a force field.

关键词： optomechanics levitated nanoparticles force field 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

On the Optimal Initial Inner-Core Size for Tropical Cyclone Intensification: An Idealized Numerical Study

引用

Advances in Atmospheric Sciences 2024年第11期41卷 2141-2155页

作者： Rong FEI Yuqing WANG School of Atmospheric Sciences and remote sensing Wuxi UniversityWuxi 214105China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China International Pacific research center Department of Atmospheric SciencesSchool of Ocean and Earth Science and TechnologyUniversity of Hawaii at ManoaHonoluluHawaii 96822USA

Recent observational and numerical studies have revealed the dependence of the intensification rate on the inner-core size of tropical cyclones(TCs). In this study, with the initial inner-core size(i.e., the radius of maximum wind—RMW)varied from 20–180 km in idealized simulations using two different numerical models, we found a nonmonotonic dependence of the lifetime maximum intensification rate(LMIR) on the inner-core size. Namely, there is an optimal innercore size for the LMIR of a TC. Tangential wind budget analysis shows that, compared to large TCs, small TCs have large inward flux of absolute vorticity due to large absolute vorticity inside the RMW. However, small TCs also suffer from strong lateral diffusion across the eyewall, which partly offsets the positive contribution from large inward flux of absolute vorticity. These two competing processes ultimately lead to the TC with an intermediate initial inner-core size having the largest LMIR. Results from sensitivity experiments show that the optimal size varies in the range of 40–120 km and increases with higher sea surface temperature, lower latitude, larger horizontal mixing length, and weaker initial TC intensity. The 40–120 km RMW corresponds to the inner-core size most commonly found for intensifying TCs in observations, suggesting the natural selection of initial TC size for intensification. This study highlights the importance of accurate representation of TC inner-core size to TC intensity forecasts by numerical weather prediction models.

关键词： tropical cyclones intensification inner-core size idealized simulations

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

Monitoring absolute vertical land motions and absolute sea-level changes from GPS and tide gauges data over French Polynesia

引用

Geodesy and Geodynamics 2024年第1期15卷 13-26页

作者： Xianjie Li Jean-Pierre Barriot Bernard Ducarme Marania Hopuare Yidong Lou Geodesy Observatory of Tahiti University of French PolynesiaFaa'a 98702French Polynesia Catholic University of Louvain Georges Lemaître Centre for Earth and Climate Research(ELI)1348 Louvain-la-NeuveBelgium GNSS research center Wuhan UniversityWuhan 430079China State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China

In this study,we estimate the absolute vertical land motions at three tidal stations with collocated Global Navigation Satellite System(GNSS)receivers over French Polynesia during the period 2007-2020,and obtain,as ancillary results,estimates of the absolute changes in sea level at the same *** verify our processing approach to determining vertical motion,we first modeled vertical motion at the International GNSS Service(IGS)THTI station located in the capital island of Tahiti and compared our estimate with previous independent determinations,with a good *** obtained the following estimates for the vertical land motions at the tide gauges:Tubuai island,Austral Archipelago-0.92±0.17 mm/yr,Vairao village,Tahiti Iti:-0.49±0.39 mm/yr,Rikitea,Gambier Archipelago-0.43±0.17 mm/*** absolute variations of the sea level are:Tubuai island,Austral Archipelago 5.25±0.60 mm/yr,Vairao village,Tahiti Iti:3.62±0.52 mm/yr,Rikitea,Gambier Archipelago 1.52±0.23 mm/*** discuss these absolute values in light of the values obtained from altimetric measurements and other means in French Polynesia.

关键词： GPS Tide gauges Sea level changes Vertical land motion

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

Development of a novel critical nitrogen concentration-cumulative transpiration curve for optimizing nitrogen management under varying irrigation conditions in winter wheat

引用

The Crop Journal 2024年第4期12卷 1242-1251页

作者： Tianyang Ye Yu Zhang Jingyan Xuan Xintian Wang Yang Li Junhao Xu Liujun Xiao Leilei Liu Liang Tang Weixing Cao Bing Liu Yan Zhu National Engineering and Technology center for Information Agriculture Engineering Research Center of Smart AgricultureMinistry of EducationKey Laboratory for Crop System Analysis and Decision MakingMinistry of AgricultureJiangsu Key Laboratory for Information AgricultureJiangsu Collaborative Innovation Center for Modern Crop ProductionNanjing Agricultural UniversityNanjing 210095JiangsuChina Institute of remote sensing and Digital Agriculture Sichuan Academy of Agricultural SciencesChengdu 610066SichuanChina

Accurate nitrogen(N)nutrition diagnosis is essential for improving N use efficiency in crop *** widely used critical N(Nc)dilution curve traditionally depends solely on agronomic variables,neglecting crop water *** three-year field experiments with winter wheat,encompassing two irrigation levels(rainfed and irrigation at jointing and anthesis)and three N levels(0,180,and 270 kg ha1),this study aims to establish a novel approach for determining the Nc dilution curve based on crop cumulative transpiration(T),providing a comprehensive analysis of the interaction between N and water *** Nc curves derived from both crop dry matter(DM)and T demonstrated N concentration dilution under different conditions with different *** equation Nc=6.43T0.24 established a consistent relationship across varying irrigation *** test results indicated that the nitrogen nutrition index(NNI),calculated from this curve,effectively identifies and quantifies the two sources of N deficiency:insufficient N supply in the soil and insufficient soil water concentration leading to decreased N availability for root ***,the NNI calculated from the Nc-DM and Nc-T curves exhibited a strong negative correlation with accumulated N deficit(Nand)and a positive correlation with relative grain yield(RGY).The NNI derived from the Nc-T curve outperformed the NNI derived from the Nc-DM curve concerning its relationship with Nand and RGY,as indicated by larger R2 values and smaller *** novel Nc curve based on T serves as an effective diagnostic tool for assessing winter wheat N status,predicting grain yield,and optimizing N fertilizer management across varying irrigation *** findings would provide new insights and methods to improve the simulations of water-N interaction relationship in crop growth models.

关键词： Crop dry matter Crop cumulative transpiration Bayesian statistical model Critical nitrogen dilution curve Nitrogen nutrition index

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

Optimal combination of the correction model and parameters for the precision geometric correction of UAV hyperspectral images

引用

International Journal of Agricultural and Biological Engineering 2024年第3期17卷 173-184页

作者： Wenzhong Tian Za Kan Qingzhan Zhao Ping Jiang Xuewen Wang Hanqing Liu College of Mechanical and Electrical Engineering Shihezi UniversityShihezi 832000XinjiangChina research center for Space Information Engineering Technology Shihezi 832000XinjiangChina XPCC Division of National remote sensing center of China Shihezi 832000XinjiangChina College of Information Science and Technology Shihezi UniversityShihezi 832000XinjiangChina

Nowadays,with the rapid development of quantitative remote sensing represented by high-resolution UAV hyperspectral remote sensing observation technology,people have put forward higher requirements for the rapid preprocessing and geometric correction accuracy of hyperspectral *** optimal geometric correction model and parameter combination of UAV hyperspectral images need to be determined to reduce unnecessary waste of time in the preprocessing and provide high-precision data support for the application of UAV hyperspectral *** this study,the geometric correction accuracy under various geometric correction models(including affine transformation model,local triangulation model,polynomial model,direct linear transformation model,and rational function model)and resampling methods(including nearest neighbor resampling method,bilinear interpolation resampling method,and cubic convolution resampling method)were ***,the distribution,number,and accuracy of control points were analyzed based on the control variable method,and precise ground control points(GCPs)were *** results showed that the average geometric positioning error of UAV hyperspectral images(at 80 m altitude AGL)without geometric correction was as high as 3.4041 m(about 65 pixels).The optimal geometric correction model and parameter combination of the UAV hyperspectral image(at 80 m altitude AGL)used a local triangulation model,adopted a bilinear interpolation resampling method,and selected 12 edgemiddle distributed *** correction accuracy could reach 0.0493 m(less than one pixel).This study provides a reference for the geometric correction of UAV hyperspectral images.

关键词： geometric correction hyperspectral images unmanned aerial vehicle(UAV) ground control point(GCP)

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

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：