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Nano Research 2024年第9期17卷 8542-8551页

作者： Cai-Liang wang Shuang Bai Pei-Yan zhao Tao Zhou Hui-Ya wang Jun-peng wang Luo-Xin wang Guang-Sheng wang School of Chemistry Beihang UniversityBeijing 100191China Aerospace Science and Industry Corporation of Wuhan Magnetoelectricity Co. Ltd.Wuhan 430070China college of Materials Science and Engineering Key Laboratory for New Textile Materials and Applications of Hubei ProvinceWuhan Textile UniversityWuhan 430200China School of Chemistry and Chemical Engineering Lingnan Normal UniversityZhanjiang 524048China School of Materials Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China

Here,we present a unique method to enhance the low-frequency absorption performance of a honeycomb absorber by integrating a *** geometrical dimensions of the proposed metasurface have been numerically *** introduction of the metasurface allows exploitation of its robust resonance and superior impedance matching in low-frequency bands,thereby improving microwave absorption *** incorporation of the metasurface does not impact the wave transmission performance of the honeycomb core absorber at high-frequency band,thus preserving its high-frequency *** broadens the absorption range,leading to an expanded *** results reveal that the composite absorber(CA)exhibits strong absorption performance with an incident angle stability up to 45°for both transverse electric(TE)and transverse magnetic(TM)*** absorption mechanism of the CA has been investigated by using an equivalent circuit model and electromagnetic field analysis.A prototype was designed,fabricated,and tested to validate the proposed *** simulation and measurement results demonstrate that the prototype can achieve an average absorption rate exceeding 90%across a 1.0-18.0 GHz *** study introduces an innovative technique for creating microwave absorbers for low-frequency wideband applications.

关键词： low frequency metasurface radar absorption impedance matching

TiO_(2) nanofiber-supported copper nanoparticle catalysts for highly efficient methane conversion to C1 oxygenates under mild conditions

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Nano Research 2024年第5期17卷 3844-3852页

作者： Wencui Li Yu Ren Zean Xie Yipeng wang Hang Zhang Dianxiang peng Hengfang Shen Hongfei Shi Jiaxin Cai peng wang Tongxin Zhang Zhen zhao State Key Laboratory of Heavy Oil Processing China University of Petroleum(Beijing)Beijing 102249China Institute of Catalysis for Energy and Environment College of Chemistry&Chemical EngineeringShenyang Normal UniversityShenyang 110034China Institute of Petrochemical Technology Jilin Institute of Chemical TechnologyJilin 132022China

The selective oxidation of methane under mild conditions remains the“Holy Grail of Catalysis”.The key to activating methane and inhibiting over-oxidation of target oxygenates lies in designing active *** nanoparticles were loaded onto TiO_(2) nanofibers using the photo-deposition *** resulting catalysts were found to effectively convert methane into C1 oxygenated products under mild *** with previously reported catalysts,it delivers a superior performance of up to 2510.7 mmol·g_(Cu)^(-1)·h^(-1) productivity with a selectivity of around 100%at 80℃for 5 *** characterizations and density functional theory(DFT)calculations indicate that TiO_(2) in the mixed phase of anatase and rutile significantly increases the Cu^(+)/CuO ratio of the supported Cu species,and this ratio is linearly related to the formation rate of oxygen-containing *** CuI site promotes the generation of active O species from H_(2)O_(2) dissociation on Cu_(2)O(111).These active O species reduce the energy barrier for breaking the C-H bond of CH_(4),thus boosting the catalytic *** methane conversion mechanism was proposed as a methyl radical pathway to form CH_(3)OH and CH_(3)OOH,and then the generated CH_(3)OH is further oxidized to HOCH_(2)OOH.

关键词： TiO_(2)nanofiber copper nanoparticles photo-deposition method methane oxidation C1 oxygenates

Effects and fate of metal-based engineered nanomaterials in soil ecosystem: A review

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Pedosphere 2024年第5期34卷 843-852页

作者： Qibin wang peng ZHANG Weichen zhao Shakoor NOMAN Adeel MUHAMMAD Guikai ZHU Yi SUN Quanlong wang Yaqi JIANG Yukui RUI Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation College of Resources and Environmental Sciences China Agricultural University Department of Environmental Science and Engineering University of Science and Technology of China School of geography Earth and Environmental Sciences University of Birmingham BNU-HKUST Laboratory of Green Innovation Advanced Institute of Natural Sciences Beijing Normal University at Zhuhai china Agricultural university Professor Workstation of Yuhuangmiao Town china Agricultural university Professor Workstation of Sunji Town

Metal-based engineered nanomaterials (MENMs) are increasingly being used in people’s working lives. Although MENMs have important effects on soil ecosystem and play an important role in solving soil environmental problems, the hazards associated with MENMs cannot be ignored. Therefore, more and more scholars have studied the behavior and effects of nanomaterials in soils in recent years. In this review, we explore the articles on MENMs and soil ecosystem retrieved from various databases from 2013 to 2022. We discuss the mechanisms of MENM toxicity, the current state of soil ecosystem, the ecological effects of MENMs on soil microbes, earthworms, and plants, and the ways by which soil organisms take up MENMs. We now know that although MENMs have positive effects on soil ecosystem, their potential hazards are not negligible. Therefore, it is necessary to investigate the effects of MENMs on soil organisms. Meanwhile, we should pay more attention to the negative effects of MENMs on soil ecosystem while exploring their positive effects on soil ecosystem in future research.

关键词： earthworm nanomaterial migration and transformation nanotechnology plant soil microorganism toxicity

Heterostructural NiFeW disulfide and hydroxide dual‐trimetallic core‐shell nanosheets for synergistically effective water oxidatio

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Carbon Energy 2024年第8期6卷 192-204页

作者： peng‐Fei Guo Yang Yang Bing Zhu Qian‐Nan Yang Yan Jia Wei‐Tao wang zhao‐Tie Liu Shi‐Qiang zhao Xun Cui Key Laboratory of Chemical Additives for china National Light Industry College of Chemistry and Chemical EngineeringShaanxi University of Science and TechnologyXi'anChina School of Chemistry and Chemical Engineering Shaanxi Normal UniversityXi'anChina Key Laboratory of Carbon Materials of Zhejiang Province Wenzhou Key Lab of Advanced Energy Storage and ConversionZhejiang Province Key Lab of Leather EngineeringCollege of Chemistry and Materials EngineeringWenzhou UniversityWenzhouChina State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhanChina

A stable and highly active core‐shell heterostructure electrocatalyst is essential for catalyzing oxygen evolution reaction(OER).Here,a dual‐trimetallic core‐shell heterostructure OER electrocatalyst that consists of a NiFeWS_(2)inner core and an amorphous NiFeW(OH)_(z)outer shell is designed and synthesized using in situ electrochemical *** electrochemical measurements of different as‐synthesized catalysts with a similar mass loading suggest that the core‐shell Ni_(0.66)Fe_(0.17)W_(0.17)S_(2)@amorphous NiFeW(OH)_(z)nanosheets exhibit the highest overall performance compared with that of other bimetallic reference catalysts for the ***,the nanosheet arrays were in situ grown on hydrophilic‐treated carbon paper to fabricate an integrated three‐dimensional electrode that affords a current density of 10 mA cm^(−2)at a small overpotential of 182 mV and a low Tafel slope of 35 mV decade^(−1)in basic *** Faradaic efficiency of core‐shell Ni_(0.66)Fe_(0.17)W_(0.17)S_(2)@amorphous NiFeW(OH)_(z)is as high as 99.5%for *** scanning electron microscope,transmission electron microscope,and X‐ray photoelectron spectroscopy analyses confirm that this electrode has excellent stability in morphology and elementary composition after long‐term electrochemical ***,density functional theory calculations further indicate that the core‐shell heterojunction increased the conductivity of the catalyst,optimized the adsorption energy of the OER intermediates,and improved the OER *** study provides a universal strategy for designing more active core‐shell structure electrocatalysts based on the rule of coordinated regulation between electronic transport and active sites.

关键词： amorphous NiFeW hydroxide core‐shell heterojunction in situ electrochemical tuning NiFeW disulfide oxygen evolution reaction

Understanding the Relationship Between Shrinking Cities and Land Prices:Spatial Pattern,Effectiveness,and Policy Implications

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Chinese Geographical Science 2024年第1期34卷 1-18页

作者： wang Xiaohui peng Li HUANG Kexin DENG Wei college of geography and Resources Sichuan Normal UniversityChengdu610101China Key Laboratory of Land Resources Evaluation and Monitoring in Southwest Ministry of EducationSichuan Normal UniversityChengdu610101China

Urban shrinkage has emerged as a widespread phenomenon globally and has a significant impact on land,particularly in terms of land use and *** study focuses on 2851 county-level cities in china in 2005–2018(excluding Hong Kong,Macao,Taiwan,and‘no data’areas in Qinhai-Tibet Plateau)as the fundamental units of *** employing nighttime light(NTL)data to identify shrinking cities,the propensity score matching(PSM)model was used to quantitatively examine the impact of shrinking cities on land prices,and evaluate the magnitude of this *** findings demonstrate the following:1)there were 613 shrinking cities in china,with moderate shrinkage being the most prevalent and severe shrinkage being the least.2)Regional disparities are evident in the spatial distribution of shrinking cities,especially in areas with diverse terrain.3)The spatial pattern of land price exhibits a significant correlated to the economic and administrative levels.4)Shrinking cities significantly negatively impact on the overall land price(ATT=–0.1241,P<0.05).However,the extent of the effect varies significantly among different spatial *** study contributes novel insights into the investigation of land prices and shrinking cities,ultimately serving as a foundation for government efforts to promote the sustainable development of urban areas.

关键词： shrinking cities land price propensity score matching(PSM) relative effectiveness china

Exploring social-ecological system resilience in South china Karst:Quantification,interaction and policy implication

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geography and Sustainability 2024年第2期5卷 289-301页

作者： Tiantian Chen Yuxi wang Li peng Chongqing Key Laboratory of Surface Process and Ecological Restoration in the Three Gorges Reservoir Area Chongqing Normal UniversityChongqing 401331China Chongqing Field Observation and Research Station of Surface Ecological Process in the Three Gorges Reservoir Area Chongqing 401331China college of geography and Resources Sichuan Normal UniversityChengdu 610066China

china’s Grain to Green Program(GTGP),which is one of the largest payments for ecosystem services(PES)in the world,has made significant ecological improvements to the ***,current understanding of its outcomes on the social-ecological system(SES)remains ***,taking the South china Karst as an example,a SES resilience evaluation index system was constructed followed by an exploratory spatial analysis,root mean square error,and Self-Organizing Feature Map to clarify the spatiotemporal changes and relationship of SES resilience,achieve the zoning of SES resilience and provide restoration *** results showed an upward trend in social resilience from 2000 to 2020,especially its subsystem of social *** ecological resilience was stable,owing to a slightly declined ecosystem services and increased landscape ***,nearly half of the counties exhibited a distribution mismatch in SES *** was an obvious inverted U-shaped relationship of SES resilience,indicating a clear threshold effect,and the constraint relation-ship of SES resilience eased over time,demonstrating the effectiveness of the ecological restoration *** played a positive role in reducing regional SES trade-off,but this positive effect was limited,reflecting the limitations of overemphasizing the conversion from farmland to forest and *** SES resilience can be divided into four clusters,which were the key optimization zone for social system,the SES resilience safety zone,the key restoration zone for SES resilience,and the key optimization zone for ecological *** adjustments for the GTGP in these zones should be taken to achieve maximum SES benefits in the future.

关键词： SES resilience Trade-off Clustering GTGP South china Karst

Automatic detection of small bowel lesions with different bleeding risks based on deep learning models

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World Journal of Gastroenterology 2024年第2期30卷 170-183页

作者： Rui-Ya Zhang peng-peng Qiang Ling-Jun Cai Tao Li Yan Qin Yu Zhang Yi-Qing zhao Jun-Ping wang Department of Gastroenterology The Fifth Clinical Medical College of Shanxi Medical UniversityTaiyuan 030012Shanxi ProvinceChina School of Computer and Information Technology Shanxi UniversityTaiyuan 030006Shanxi ProvinceChina School of Life Sciences and Technology Mudanjiang Normal UniversityMudanjiang 157011Heilongjiang ProvinceChina

BACKGROUND Deep learning provides an efficient automatic image recognition method for small bowel(SB)capsule endoscopy(CE)that can assist physicians in ***,the existing deep learning models present some unresolved *** To propose a novel and effective classification and detection model to automatically identify various SB lesions and their bleeding risks,and label the lesions accurately so as to enhance the diagnostic efficiency of physicians and the ability to identify high-risk bleeding *** The proposed model represents a two-stage method that combined image classification with object ***,we utilized the improved ResNet-50 classification model to classify endoscopic images into SB lesion images,normal SB mucosa images,and invalid ***,the improved YOLO-V5 detection model was utilized to detect the type of lesion and its risk of bleeding,and the location of the lesion was *** constructed training and testing sets and compared model-assisted reading with physician *** The accuracy of the model constructed in this study reached 98.96%,which was higher than the accuracy of other systems using only a single *** sensitivity,specificity,and accuracy of the model-assisted reading detection of all images were 99.17%,99.92%,and 99.86%,which were significantly higher than those of the endoscopists’*** image processing time of the model was 48 ms/image,and the image processing time of the physicians was 0.40±0.24 s/image(P<0.001).CONCLUSION The deep learning model of image classification combined with object detection exhibits a satisfactory diagnostic effect on a variety of SB lesions and their bleeding risks in CE images,which enhances the diagnostic efficiency of physicians and improves the ability of physicians to identify high-risk bleeding groups.

关键词： Artificial intelligence Deep learning Capsule endoscopy Image classification Object detection Bleeding risk

Radial growth in Qinghai spruce is most sensitive to severe drought in the Qilian Mountains of Northwest china

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Journal of Forestry Research 2024年第3期35卷 73-86页

作者： Xuge wang Liang Jiao Ruhong Xue peng Zhang Dashi Du Mengyuan Wei Qian Li college of geography and Environmental Science Northwest Normal UniversityNo.967Anning East RoadLanzhou 730070People's Republic of China Key Laboratory of Resource Environment and Sustainable Development of Oasis Northwest Normal UniversityLanzhou 730070Gansu ProvincePeople's Republicof China

Global warming and frequent extreme drought events lead to tree death and extensive forest decline,but the underlying mechanism is not *** drought years,cambial development is more sensitive to climate change,but in different phenological stages,the response rela-tionship is ***,the dynamic relationship between tree radial growth and climatic/environmental fac-tors needs to be *** thus continuously monitored radial growth of Qinghai spruce(Picea crassifolia Kom.)and environmental factors from January 2021 to November 2022 using point dendrometers and portable meteorological weather stations in the central area of the Qilian *** relationship and stability between the radial growth of Qinghai spruce and environmental factors were compared for different levels of drought in 2021 and *** year 2022 had higher temperatures and less precipitation and was drier than *** with 2021,the growing period in 2022 for Qinghai spruce was 10 days shorter,maximum growth rate(Grmax)was 4.5μm·d^(-1) slower,and the initiation of growth was 6 days *** of Qinghai spruce was always restricted by drought,and the stem radial increment(SRI)was more sensitive to precipitation and air relative *** changes in cumulative radial growth were divided into four phenological stages according to the time of growth onset,cessation,and maximum growth rate(Grmax)of Qinghai *** responses of SRI to climate change were stronger in Stage 3 and Stage 4 of 2021 and stronger in Stage 1(initiation growth stage)and Stage 3 of *** results provide important information on the growth of the trees in response to drought and for specific managing forests as the climate warms.

关键词： Picea crassifolia Radial growth dynamics Severe drought Response stability Point dendrometer

Multiomics analyses of two Leonurus species illuminate leonurine biosynthesis and its evolution

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Molecular Plant 2024年第1期17卷 158-177页

作者： peng Li Meng-Xiao Yan Pan Liu Dan-Jie Yang Ze-Kun He Yun Gao Yan Jiang Yu Kong Xin Zhong Sheng Wu Jun Yang Hong-Xia wang Yan-Bo Huang Le wang Xiao-Ya Chen Yong-Hong Hu Qing zhao Ping Xu shanghai Key Laboratory of Plant Functional Genomics and Resources Shanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChineseAcademy of SciencesShanghaiChina college of Life Sciences Shanghai Normal UniversityShanghai 200234China State Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghaiChina university of the Chinese Academy of Sciences Beijing 100049China The Research Center of Chiral Drugs Innovation Research Institute of Traditional Chinese MedicineShanghai University of Traditional Chinese Medicine1200 Cailun RoadShanghai 201203China college of Chemistry and Chemical Engineering Shanghai University of Engineering ScienceShanghai 201620China

The Lamiaceae family is renowned for its terpenoid-based medicinal components,but Leonurus,which has traditional medicinal uses,stands out for its alkaloid-rich ***,the principal active compound found in Leonurus,has demonstrated promising effects in reducing blood lipids and treating ***,the biosynthetic pathway of leonurine remains largely ***,we present the chromosome-level genome sequence assemblies of Leonurus japonicus,known for its high leonurine production,and Leonurus sibiricus,characterized by very limited leonurine *** integrating genomics,RNA sequencing,metabolomics,and enzyme activity assay data,we constructed the leonurine biosynthesis pathway and identified the arginine decarboxylase(ADC),uridine diphosphate glucosyltransferase(UGT),and serine carboxypeptidase-like(SCPL)acyltransferase enzymes that catalyze key reactions in this *** analyses revealed that the UGT–SCPL gene cluster evolved by gene duplication in the ancestor of Leonurus and neofunctionalization of SCPL in ***,which contributed to the accumulation of leonurine specifically in ***,our comprehensive study illuminates leonurine biosynthesis and its evolution in Leonurus.

关键词： Lamiaceae Leonurus japonicus Leonurus sibiricus genome sequence alkaloids leonurine gene cluster biosynthetic pathway evolution