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表面应力介导的碳基Pt纳米催化剂用于硝基芳烃的高选择性加氢 认领 引用 被引量：1
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作者 张锋伟 郭河芳 +5 位作者 刘萌萌 赵阳 洪峰 李静静 董正平 乔波涛 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第5期195-204,共10页
苯胺衍生物是合成药物、杀虫剂、颜料和染料等化工原料的重要中间体,其主要由硝基芳烃选择加氢制得.该反应通常在较高的温度和压力下进行,尤其是底物中含有其他官能团(如卤素、醛、酮和酯等)会因脱卤和过度加氢造成产物的选择性下降,其... 苯胺衍生物是合成药物、杀虫剂、颜料和染料等化工原料的重要中间体,其主要由硝基芳烃选择加氢制得.该反应通常在较高的温度和压力下进行,尤其是底物中含有其他官能团(如卤素、醛、酮和酯等)会因脱卤和过度加氢造成产物的选择性下降,其原因可能是-C-X和-C=C双键比-NO2基团具有更高反应活性以及它们在催化剂表面的不同吸附强度和构型.因此,含竞争官能团的硝基芳烃定向转化从根本上取决于高选择性加氢催化剂的合理设计与制备.为实现含有可还原性基团的硝基芳烃高选择性加氢,研究人员开发了多种方法来构建Pd、Pt基非均相催化剂,如有机分子修饰金属表面、产生载体氧空位、降低金属颗粒组装体尺寸、构筑核壳结构复合材料以及与第二种金属形成合金/金属间化合物.本文采用一种简便可放大的热还原策略合成具有高选择性和稳定的表面应变铂基纳米催化剂(Pt NPs).通过溶剂热法制备Pt/OCNTs预催化剂,然后在H2气氛下对其进行高温处理获得目标催化剂.在该过程中,Pt NPs尺寸稍微增加且被迁移的碳原子覆盖,碳原子源自CNTs载体.Pt NPs外围保护性碳层可有效抑制其聚集和浸出,有望提高催化剂的选择性和稳定性.结合球差校正透射电子显微镜、X-射线吸收精细结构谱和X-射线光电子能谱分析,在退火过程中发现Pt NPs和CNTs载体之间存在较强的金属-载体相互作用(SMSI),进一步升温后Pt NPs表面的部分碳涂层被蚀刻成碳原子,并在Pt NPs表面诱导产生压缩应变.因此,Pt/OCNTs催化剂的热还原处理成功地诱导了Pt NPs和CNTs载体之间的SMSI效应以及Pt NPs的压缩应变.将制备的催化剂用于硝基芳烃底物的选择性加氢,结果表明,表面应变的Pt/CNTs-800H(在氢气气氛中,800℃热处理)催化剂对苯乙烯和硝基苯混合物及4-硝基苯乙烯加氢的化学选择性几乎完全反转,说明CNTs惰性载体在将Pt NPs从非选择性催化剂转化为对4-硝基苯乙烯高选择性加氢催化剂中起到关键作用.硝基芳烃加氢反应结果表明,经高温H2处理后的Pt/CNTs-800H催化剂的加氢选择性显著提高且对4-溴硝基苯加氢具有较好的循环稳定性.同时,该策略也适用于5wt%Pt/C和PtGO催化剂,证明本文处理方法在碳基催化材料中的良好普适性.综上,本文不仅发现Pt NPs和CNTs之间存在SMSI效应,而且为制备具有压缩应变的Pt NPs提供了一种新途径,为解决Pt基非均相催化剂选择性差和稳定性低等问题提供一定参考. 展开更多
关键词 铂基纳米催化剂 热还原处理 金属载体强相互作用 压缩应变 选择性加氢
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Biological Characteristics of Aeromonas Strains in Nanchang Area 认领 引用 被引量：1
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作者 Xinyi SHAN Dongxu WEN +5 位作者 Xiaolan LIU Wangming TAO Mengjuan ZHANG Wei QI Fengwei ZHANG Zhixiu ZHU 《Agricultural Biotechnology》 2019年第3期107-111,179,共5页
[Objectives]This study was conducted to find effective measures to prevent and control Pelteobagrus fulvidraco hemorrhage.[Methods]Typical disease materials were collected for bacterial isolation and culture and biolo... [Objectives]This study was conducted to find effective measures to prevent and control Pelteobagrus fulvidraco hemorrhage.[Methods]Typical disease materials were collected for bacterial isolation and culture and biological characteristics detection,and morphological characteristics were observed by pure culture method.Biochemical characteristics were identified by micro biochemical method.Molecular identification was performed by PCR amplification method.Drug resistance was detected by disk diffusion method.The agar diffusion method was used for the detection of in-vitro inhibitory effect.The immunogenicity of the isolates was detected by subcutaneous immunoassay.The virulence factor was detected by spot inoculation.The intraperitoneal injection was used for the detection of pathogenicity.[Results]The isolates were round,grayish white,and identified as Aeromonas.They fermented maltose,glucose,etc.,did not ferment lactose,and were negative for urea and H2S and positive for lysine and arginine.The target fragment appeared at 1 500,and the sequences shared the highest homology with Aeromonas.The isolates were highly susceptible to amikacin and gentamicin,and resistant to penicillin G and tetracycline.Eight lactic acid bacteria strains produced 1.1-1.9 cm of inhibition zone against the isolates.After the second vaccination,the titer reached 2^13;both hemolysin and protease were produced;and the test mice died within 24 h.[Conclusions]The isolates are Aeromonas,and have strong drug resistance,immunogenicity and pathogenicity.Inactivated emusion-oil vaccines of Aeromonas combined with the co-use of lactic acid bacteria and susceptible drugs can prevent the outbreak of diseases caused by Aeromonas. 展开更多
关键词 Pelteobagrus fulvidraco Aeromonas Biological characteristics
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酞菁镍分子结构的精确设计:优化电子和空间效应用于CO2电还原 认领 引用
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作者 李静静 张锋伟 +5 位作者 詹新雨 郭河芳 张涵 昝文艳 孙振宇 张献明 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第5期117-126,共10页
大气中CO2浓度的快速增加对气候变化和人类生存环境造成严重威胁,亟需开发新的方法与技术来捕获CO2并将其转化为高附加值产品.传统的热催化技术通过选择性加氢和环加成等技术路线可将CO2转化为低碳烷烃、醇类和碳酸二甲酯等化... 大气中CO2浓度的快速增加对气候变化和人类生存环境造成严重威胁,亟需开发新的方法与技术来捕获CO2并将其转化为高附加值产品.传统的热催化技术通过选择性加氢和环加成等技术路线可将CO2转化为低碳烷烃、醇类和碳酸二甲酯等化工品.与之相比,洁净的催化技术如CO2电还原(CO2RR)具有反应条件温和、操作简单、能量利用率高和产品类型可控等特点而备受关注.将CO2电还原为各种气体或液体产物是CO2转化的理想策略,具有广阔的应用前景.然而,实现CO2的高效电还原需要克服以下瓶颈,包括CO2还原的电位过高、产物选择性差和竞争性析氢反应严重等问题.为了在低过电位、高选择性、高稳定性和大电流密度下进行CO2RR,人们研究了不同类型的杂化纳米催化剂,包括无金属碳材料,金属/金属氧化物和金属硫化物电催化剂等.最近研究人员报道了CoPc(NH2)4和CoPc(CN)8分子催化剂并应用于CO2RR,但缺乏对取代基的位阻分布和电子推拉效应对CO2RR性能影响的相关研究.因此,开发具有特定官能团取代基和明确结构的新型分子基催化剂,进而深入研究其对CO2RR的影响显得极为重要.本文通过两步合成策略构建了一系列具有不同官能团和位置取代的酞菁镍(NiPc)分子衍生物(α-NO2,α-NH2,β-NO2和β-NH2).将这些NiPc分子衍生物通过简单的机械混合固定在氧化碳纳米管(CNTs)表面,得到分子级分散的电催化剂(MDEs).深入探讨了NiPc基分子催化剂的几何效应和电子效应对CO2RR催化性能的影响规律,从根本上了解CO2RR的活化路径、反应机理和构效关系.结果表明,NiPc(α-NO2)4/CNTs催化剂对CO2RR具有最佳的催化性能,在相对可逆电压-1.0V时电流密度为7.01 mA cm-2和FECO为99%,在宽电势范围-0.7~-1.2 V,FECO超过91.1%,与密度泛函理论计算结果一致,表明NiPc(α-NO2)4/CNTs吸电子和邻位取代-NO2是CO2RR生产CO最合适的催化剂.通过红外谱图证实了具有不同空间取代基团的NiPc衍生物的成功制备.透射电镜结果表明,碳纳米管载体具有均匀的管状结构.球差电镜显示有大量的亮点,说明金属Ni以单原子的形式存在,结合同步辐射结果表明Ni的价态在0和+2之间,进一步证明Ni物种是原子分散的,并且与N原子配位.NiPc/CNTs的高分辨率N 1s XPS谱可以分峰为吡啶N(398.5 eV)和Ni-N(399.6 eV).相比之下,NiPc(α-NO2)4/CNTs中的Ni-N(400.9eV)的结合能高于NiPc/CNTs,而NiPc(α-NH2)4/CNTs中的Ni-N(399.4 eV)结合能低于NiPc/CNTs.NiPc/CNTs的Ni 2p XPS谱包括以872.3和854.9 eV为中心的两个峰,分别对应于Ni2p1/2和Ni 2p3/2.Ni 2p在NiPc(α-NO2)4/CNTs(Ni 2p1/2873.3 eV和Ni 2p3/2855.9 eV)中的结合能高于NiPc/CNTs.结果表明,吸电子的-N02基团从Ni-N4活性位点得到电子,从而使结合能转移到更高的位置.反之,NiPc(α-NH2)4/CNTs(Ni 2p1/2872.2eV和Ni 2p3/2854.1 eV)的结合能低于NiPc/CNTs的,表明供电子基团使结合能向较低的位置移动.此外,通过Mulliken电荷分析,计算了不同NiPc基分子催化剂中Ni原子与邻近原子之间的电荷转移,与NiPc分子基团的推拉电子效应和外围取代基的空间位置密切相关.电催化结果表明,NiPc(α-NO2)4/CNTs的FECO在-1.0 V时最大,为99.0%,这与计算结果α-NO2取代的NiPc可以使*COOH形成的能垒最小,显著提高了CO2RR性能结果一致.综上,本研究在分子水平上为精准设计和制备具有较好的CO2RR催化活性和选择性的电催化剂提供参考. 展开更多
关键词 二氧化碳还原 精准设计 电催化剂 酞菁镍
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Deciphering the skeletal interoceptive circuitry to controlbone homeostasis 认领 引用 被引量：1
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作者 Yefeng Wu Jiusi Guo +5 位作者 Zhen Chen Fengwei Zhang Billy Kwok Chong Chow Zhuofan Chen Kelvin Wai-Kwok Yeung Wei Qiao 《BMEMat(BioMedical Engineering Materials)》 CAS CSCD 2025年第3期11-45,共35页
Bone tissue is richly innervated,and the influence of the nervous system on the physiological and pathological status of bone tissue has emerged as a significant research focus.The recent discovery of the skeletal int... Bone tissue is richly innervated,and the influence of the nervous system on the physiological and pathological status of bone tissue has emerged as a significant research focus.The recent discovery of the skeletal interoceptive circuits further emphasizes the crucial role of the central nervous system in the control of bone homeostasis.Skeletal interoception represents one of the most intricate mechanisms in the human body for maintaining bone homeostasis,as it involves the orchestrated efforts of skeletal,nervous,immune,and endocrine systems.In this review,we comprehensively introduce the three primary components of the skeletal interoceptive circuitry,including the ascending pathways that perceive and convey signals to the central nervous system,the central neural pathways that process and interpret these signals,and the descending pathways that mediate the regulatory effects on bone tissue.We also discuss how innovative therapeutic strategies can be developed to modulate bone homeostasis by leveraging the most updated findings on skeletal interoceptive circuitry.We anticipate that the application of knowledge on skeletal interoception will lead to a paradigm shift in the field of orthopaedics and biomaterials. 展开更多
关键词 bone homeostasis hypothalamus interoception nervous system
Heterogeneously Catalytic Synthesis of Au13Nanocluster 认领 引用
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作者 Yuan Wang Peihao Liu +6 位作者 Hongjin Li Ting Li Pengfei Wang Jing Dong Fengwei Zhang Zhe-Ning Chen Huan Li 《CCS Chemistry》 CSCD 2025年第9期2579-2586,共8页
A cornerstone of chemical science,catalysis underpins the majority of modern chemical manufacture.This study introduces the concept and application of heterogeneous catalysis into the synthesis of an atomically precis... A cornerstone of chemical science,catalysis underpins the majority of modern chemical manufacture.This study introduces the concept and application of heterogeneous catalysis into the synthesis of an atomically precise gold nanocluster(NC),PPh4[Au13(TBBT)4(Dppe)4]Br2(Au13).Employing a commercially available Pd/C catalyst,the synthesis was realized using a simple precursor—HAuCl4and ligands—at room temperature under a H2atmosphere.The uncatalyzed reaction without Pd was ineffective,even at elevated temperatures(80°C).Control experiments combined with characterizations and theoretical studies confirm that H2must be activated by Pd/C first.The formed Pd hydride promotes the reduction of Au(I)to Au(0)through a proton-coupled electron transfer mechanism,initiating the formation of Au13.And the hydrides are subsequently oxidized to protons,which are neutralized by a base(e.g.,NaOH).The synthetic reaction is essentially a Pd-catalyzed redox reaction.Importantly,Pd/C can be readily recovered and reused for the next synthesis.This approach paves the way for the creation of metal NCs through catalytic means. 展开更多
关键词 heterogeneous catalysis Au nanocluster atomic precision proton-coupled electron transfer electrochemical CO2reduction
Motion simulation and test on threshed grains in tapered threshing and transmission device for plot wheat breeding based on CFD-DEM 认领 引用 被引量：24
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作者 Fei Dai Xuefeng Song +3 位作者 Wuyun Zhao Zhengsheng Han Fengwei Zhang Shilin Zhang 《International Journal of Agricultural and Biological Engineering》 SCIE 2019年第1期66-73,共8页
Mechanization of field experiments is the only way to improve crop breeding and seed propagation effects.In order to further clarify and improve the working performance of tapered threshing device for plot breeding,an... Mechanization of field experiments is the only way to improve crop breeding and seed propagation effects.In order to further clarify and improve the working performance of tapered threshing device for plot breeding,and reduce the remaining seeds in the device,the numerical simulation was carried out on the motion process of materials in the longitudinal-axial tapered cylinder threshing and transmission device of the plot wheat breeding combine harvester based on CFD-DEM method.Simulation results showed that,threshing and transmission of particles and short stalks at axial direction could be realized under the influence of air flow.Meanwhile,the material transference and distribution rule and stream field distribution rule of air flow in the threshing and transmission device were obtained,the variations of velocity and displacement of particles and short stalks with time were obtained;the motion trajectories and forms of particles in different types of retention were also studied.At rotating speed of 1300-1600 r/min for the tapered threshing cylinder in the verification test,the particle retention rate in the enclosure was 0-0.13%,while in the simulation the particle retention rate in the enclosure was 0-0.11%,only a 0.02%difference between them.The results proved a favorable feasibility to simulate the working performance of the tapered threshing and transmission device for plot breeding through gas-solid coupling method. 展开更多
关键词 particle threshing and transmission tapered threshing and transmission device hydromechanics calculation discrete element numerical simulation test
Simulation and test on separating cleaning process of flax threshing material based on gas-solid coupling theory 认领 引用 被引量：24
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作者 Fei Dai Xuefeng Song +3 位作者 Wenjuan Guo Wuyun Zhao Fengwei Zhang Shilin Zhang 《International Journal of Agricultural and Biological Engineering》 SCIE 2020年第1期73-81,I0001,共9页
In order to further clarify and improve the working performance of separating cleaning device of flax threshing material,and study the motion law and characteristics of components of flax threshing material,in this pa... In order to further clarify and improve the working performance of separating cleaning device of flax threshing material,and study the motion law and characteristics of components of flax threshing material,in this paper,numerical simulation was carried out on the separating cleaning process of flax threshing material based on CFD-DEM method.Simulation results showed that the components of flax threshing material were separated and cleaned under the influence of airflow field,meanwhile,variation curves of quantity and mean velocity of flax seeds in the separating cleaning system were obtained.By referring to streamline distribution of gas-solid coupling,the quantity variation law of components of flax threshing material with time was explored and their motion curves and variation tendency of average velocity were studied.Verification test results showed that the cleaning rate of separating cleaning device for flax threshing material was 92.66%with 1.58%of total separation loss.Compared with simulation results,the test results were 1.34%and 0.93%lower,showing that it is feasible to apply the gas-solid coupling theory and method to simulate the separating and cleaning operation of flax threshing material. 展开更多
关键词 flax threshing material separating cleaning device hydromechanics calculation discrete element numerical simulation test
Design and field test of crosswise belt type whole plastic-film ridging-mulching corn seeder on double ridges 认领 引用 被引量：15
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作者 Fei Dai Wenjuan Guo +3 位作者 Xuefeng Song Ruijie Shi Wuyun Zhao Fengwei Zhang 《International Journal of Agricultural and Biological Engineering》 SCIE 2019年第4期88-96,共9页
In order to realize seedbed mechanization of whole plastic-film mulching on double ridges and to overcome the difficulty in crosswise belt type soil covering by whole plastic-film,a kind of crosswise belt type whole p... In order to realize seedbed mechanization of whole plastic-film mulching on double ridges and to overcome the difficulty in crosswise belt type soil covering by whole plastic-film,a kind of crosswise belt type whole plastic-film ridging-mulching corn seeder on double ridges was designed in this study.The key components of the sample machine was designed and its working parameters of seedbed soil covering device,crosswise-belt soil covering mechanism and profiling sowing depth adjustment device were determined.After numerical simulation on the film edge and crosswise soil covering by whole plastic-film on double ridges by discrete element method,the velocity and displacement of the oscillating plate,and the variation rule of amount of covered soil with time were explored.Field test results show that,when the advancing velocity of the machine was 0.50 m/s,the qualified rate of soil width covered on film edge of the seedbed reached 96.1%,qualified rate of crosswise soil belt width was 94.5%,qualified rate of soil thickness on seedbed was 95.3%,qualified rate of sowing depth was 89.3%,qualified rate of spacing between crosswise soil belts reached 93.6%,which all met related standards in China and satisfied design requirements,and could realize seedbed mechanization of whole plastic-film mulching on double ridges.Comparison tests on working performances of practical soil covering show a basic consistence with the seedbed soil covering simulation,and verified the effectiveness of the soil covering model built by using discrete element method. 展开更多
关键词 whole plastic-film on double ridges crosswise belt soil covering combined machine discrete element numerical simulation field test
Mechanism analysis and performance improvement of mechanized ridge forming of whole plastic film mulched double ridges 认领 引用 被引量：7
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作者 Fei Dai Xuefeng Song +3 位作者 Wuyun Zhao Ruijie Shi Fengwei Zhang Xuekun Zhang 《International Journal of Agricultural and Biological Engineering》 SCIE 2020年第5期107-116,共10页
In order to achieve high-performance and mechanization construction standard of whole plastic mulched double ridge seedbed,and to meet its forming process and corresponding agronomic requirements of the mechanized dou... In order to achieve high-performance and mechanization construction standard of whole plastic mulched double ridge seedbed,and to meet its forming process and corresponding agronomic requirements of the mechanized double ridge seedbed,the key working parameters such as the speed of rotary blade group,the thickness of upturned sod and the power consumption of rotary blade group under different parameters were analyzed based on related working performance in ridge forming.Also,the test factors and their range of values were finally determined in this study.Discrete element method(DEM)simulation was applied in the numerical simulation of the mechanized ridge forming process of whole plastic mulched double ridges,and the ridge forming effect and digging resistance variation characteristics of different types of shovels were compared.Taking the forward speed of the combined machine,the penetration angle of the arc-shaped shovel and the depth of rotary tillage as independent variables,and the qualified rate of seedbed tillage as the response value,the mathematical model between the test factors and the qualified rate of the seedbed tillage was established,to explore the influence sequence of the factors on the qualified rate of seedbed tillage,and obtained the following optimal working parameters of the ridge forming device:the advancing velocity of the combined machine of 0.50 m/s,penetration angle of the arc-shaped shovel of 31°,rotary tillage depth of 140 mm,and average qualified rate 95.20%of seedbed tillage in corresponding simulation verification test.Field test showed that the average qualified rate of seedbed tillage in ridge forming device was 93.60%,which was close to that of the simulation results.The actual working condition of the sample machine was basically in line with the simulation process and could relatively precisely reflect the mechanized ridge forming mechanism of whole plastic double ridges.The results showed that the established DEM model and its parameter setting were relatively accurate and reasonable. 展开更多
关键词 whole plastic film mulched double ridges mechanized ridge forming DEM numerical simulation parameter optimization
Evolution and legacy of East Asian aurochs 认领 引用 被引量：3
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作者 Jiawen Hou Xiwen Guan +24 位作者 Xiaoting Xia Yang Lyu Xin Liu Yuri Mazei Ping Xie Fengqin Chang Xiaonan Zhang Jialei Chen Xinyi Li Fengwei Zhang Liangliang Jin Xiaoyu Luo Mikkel-Holger SSinding Xin Sun Alessandro Achilli Nicola Rambaldi Migliore Dongju Zhang Johannes ALenstra Jianlin Han Qiaomei Fu Xinyi Liu Xiaoming Zhang Ningbo Chen Chuzhao Lei Hucai Zhang 《Science Bulletin》 SCIE EI CAS CSCD 2024年第21期3425-3433,共9页
Aurochs(Bos primigenius),once widely distributed in Afro-Eurasia,became extinct in the early 1600 s.However,their phylogeography and relative contributions to domestic cattle remain unknown.In this study,we analyzed 1... Aurochs(Bos primigenius),once widely distributed in Afro-Eurasia,became extinct in the early 1600 s.However,their phylogeography and relative contributions to domestic cattle remain unknown.In this study,we analyzed 16 genomes of ancient aurochs and three mitogenomes of ancient bison(Bison priscus)excavated in East Asia,dating from 43,000 to 3,590 years ago.These newly generated data with previously published genomic information on aurochs as well as ancient/extant domestic cattle worldwide through genome analysis.Ourfindings revealed significant genetic divergence between East Asian aurochs and their European,Near Eastern,and African counterparts on the basis of both mitochondrial and nuclear genomic data.Furthermore,we identified evidence of geneflow from East Asian aurochs into ancient and present-day taurine cattle,suggesting their potential role in facilitating the environmental adaptation of domestic cattle. 展开更多
关键词 East Asian aurochs Ancient DNA Cattle domestication Adaptive introgression
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Film identification method based on improved deeplabv3+ for full-film double-ditch corn seedbed 认领 引用 被引量：2
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作者 Fei Dai Xiangzhou Li +3 位作者 Ruijie Shi Fengwei Zhang Wuyun Zhao Wenjuan Guo 《International Journal of Agricultural and Biological Engineering》 SCIE 2023年第5期165-172,共8页
This study aimed to investigate the task demand of intelligent unmanned fertilizer application in seedling stage of corn planted in full-film double-ditch seedbed,a film identification method based on improved DeepLab... This study aimed to investigate the task demand of intelligent unmanned fertilizer application in seedling stage of corn planted in full-film double-ditch seedbed,a film identification method based on improved DeepLabv3+ identification method for full-film double-ditch corn seedbed was proposed.The differences in performance indicators of the original Deeplabv3+ network taking Xception as the backbone network and the network model that replaced three lightweight backbone networks,MobileNetV2,MobileNetV3 and GhostNet were tested.At the same time,the network models,classical semantic segmentation was introduced to PSPNet and UNet for comparative test.The MIoU of DeepLabv3+ network model that replaced its backbone network increased by 5.01%,and FPS improved by 206%compared with original network,and the model size reduced by 90.3%.The three DeepLabv3+ models after replacing the backbone network were further compressed,and the two-layer expansion convolution with low expansion rate in ASPP was deleted,and the common convolution after feature fusion was replaced by the depthwise separable convolution to obtain a lightweight network model.After testing the improved network model,it was found that the average decline of precision indicators was only 0.17%,FPS raised to 66.5,with an average increase of 25.5%,and the size of the model was compressed to 10.53 MB.Test results showed that,the improved model showed excellent performance,and could provide important technology and method support for the research and development of intelligent topdressing and field management on full-film double-ditch corn seedbed during seedling stage. 展开更多
关键词 fertilizer application intelligent unmanned machine full-film double-ditch corn seedbed film identification method deep learning semantic segmentation DeepLabv3+
A Top-Down Approach towards Cu(I)Alkynyl Clusters with Unusual Geometry 认领 引用 被引量：2
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作者 Huan Li Ting Li +4 位作者 Shuimiao Liu Mei Qu Linfeng Liang Fengwei Zhang Xian-Ming Zhang 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2021年第4期937-941,共5页
Main observation and conclusion To search for novel Cu(I)complexes,traditional approaches focus on designing and screening ligands,metal precursors and reaction parameters.In this report,we propose a top-down approach... Main observation and conclusion To search for novel Cu(I)complexes,traditional approaches focus on designing and screening ligands,metal precursors and reaction parameters.In this report,we propose a top-down approach,in which Cu precursor is first reduced to nanoparticles in the presence of alkynyl and phosphine ligands. 展开更多
关键词 Copper Top-down Cluster Fluorescence Alkynyl
Single atom Pd1/ZIF-8 catalyst via partial ligand exchange 认领 引用 被引量：1
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作者 Xin Li Fengwei Zhang +5 位作者 Xu Han Jun-Hao Wang Xiaoqin Cui Peng Xing Huan Li Xian-Ming Zhang 《Nano Research》 SCIE EI CSCD 2023年第5期8003-8011,共9页
A partial ligand exchange strategy for fabricating catalytically active single palladium site immobilized on zeolitic imidazolate framework-8(ZIF-8,Pd1/ZIF-8)is proposed in this work.The one-step synthesis simply invo... A partial ligand exchange strategy for fabricating catalytically active single palladium site immobilized on zeolitic imidazolate framework-8(ZIF-8,Pd1/ZIF-8)is proposed in this work.The one-step synthesis simply involves reacting Na2PdCl4 with ZIF-8 in solvent.The Cl ligands of Na2PdCl4 exchanged with 2-methylimidazole(2-MeIm)of the framework,resulting in the anchoring Pd on the framework and dissociation of Zn into the solution.The whole synthesis is performed at ambient conditions and the crystalline integrity of ZIF-8 is well retained.The resulting Pd1/ZIF-8 is extensively characterized by different techniques which confirm the proposed mechanism.Pd1/ZIF-8 is also successfully applied in the size-selective semi-hydrogenation of alkynes. 展开更多
关键词 single atom catalyst metal-organic frameworks ligand exchange hydrogenation
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