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Comparison of fish communities using environmental DNA metabarcoding and capture methods in a plateau Erhai Lake,China

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Journal of Oceanology and Limnology 2024年第5期42卷 1597-1608页

作者： hong CHEN Wanchao HE Fenge YANG Li LIAO Chengjie YIN Yushun CHEN Longgen guo State Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China University of Chinese Academy of Sciences Beijing 100049China Dali Monitoring Station of Yunnan Ecology and Environment Bureau Dali 671000China

Environmental DNA(eDNA)has been used as an important tool for fish diversity analysis,which can greatly solve the problems in traditional survey ***,little work has been done on the actual monitoring accuracy of *** this study,we analyzed the current status of fish resources in Erhai Lake in Yunnan,SW China,by dividing the lake into three sectors according to habitat differences,and compared the results of eDNA and traditional capture methods to investigate the shortcomings of the current analysis of eDNA results.A total of 2. fish species were detected by eDNA and traditional capture methods,including 2. and 19 fish species,respectively,and additional differences in fish composition between the two *** alpha diversity showed higher fish abundance and lower fish diversity by eDNA method compared to the traditional capture method,demonstrating that eDNA was not superior for use in fish diversity *** community similarity analysis showed that community differences were generally significant for eDNA(P<0.05).RDA analysis indicated that environmental factors did not significantly affect fish communities monitored by the eDNA ***,water temperature,aquatic plants,and water depth had significant(P<0.05)effects on fish communities in the traditional capture method,suggesting that eDNA results are insensitive to the effects of environmental *** results illustrate the effectiveness of eDNA in fish identification and the issues in quantification compared to traditional capture ***,combining eDNA with traditional methods is a more effective method for analyzing eDNA metabarcoding,following which the protocols of both quantitative methods can be designed to explore the regularity of eDNA quantification.

关键词： environmental DNA traditional capture method fish communities habitat differences Erhai Lake

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Grain yield and N uptake of maize in response to increased plant density under reduced water and nitrogen supply conditions

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Journal of Integrative Agriculture 2024年第1期23卷 122-140页

作者： Jingui Wei Qiang Chai Wen Yin hong Fan Yao guo Falong Hu Zhilong Fan QimingWang State Key Laboratory of Aridland Crop Science Lanzhou 730070China College of Agronomy Gansu Agricultural UniversityLanzhou 730070China College of Life Sciences Northwest Normal UniversityLanzhou 730070China

The development of modern agriculture requires the reduction of water and chemical N fertilizer *** the planting density can maintain higher yields,but also consumes more of these restrictive ***,whether an increased maize density can compensate for the negative effects of reduced water and N supply on grain yield and N uptake in the arid irrigated areas remains *** study is part of a long-term positioning trial that started in 2.16.A split-split plot field experiment of maize was implemented in the arid irrigated area of northwestern China in 2.2. to *** treatments included two irrigation levels:local conventional irrigation reduced by 2.%(W1,3,2.0 m^(3)ha^(-1))and local conventional irrigation(W2.4,050 m^(3)ha^(-1));two N application rates:local conventional N reduced by 2.%(N1,2.0 kg ha^(-1))and local conventional N(360 kg ha^(-1));and three planting densities:local conventional density(D1,75,000 plants ha^(-1)),density increased by 30%(D2.97,500 plants ha-1),and density increased by 60%(D3,12.,000 plants ha^(-1)).Our results showed that the grain yield and aboveground N accumulation of maize were lower under the reduced water and N inputs,but increasing the maize density by 30% can compensate for the reductions of grain yield and aboveground N accumulation caused by the reduced water and N *** water was reduced while the N application rate remained unchanged,increasing the planting density by 30% enhanced grain yield by 13.9% and aboveground N accumulation by 15.3%.Under reduced water and N inputs,increasing the maize density by 30% enhanced N uptake efficiency and N partial factor productivity,and it also compensated for the N harvest index and N metabolic related enzyme *** with W2.2.1,the N uptake efficiency and N partial factor productivity increased by 2..6 and 17.6%under W1N1D2.W1N2.2.had 8.4% higher N uptake efficiency and 13.9% higher N partial factor productivity than W2.2.1.W1N2.2.improv

关键词： water and N reduction plant density maize grain yield N uptake compensation effect

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Decomposition of pre-existing Au–P clusters induced in situ a-Fe grains uniformization in Fe–P-based nanocrystalline alloys

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Rare Metals 2024年第10期43卷 5242-5255页

作者： Min-Hao Han Cheng Sun guo-guo Xi Yang Meng Qiang Luo Xue-Qian Yu Wen-Feng Zhang Hao Liu {2.-Jie Xu Tao Zhang Key Laboratory of Aerospace Materials and Performance(Ministry of Education) School of Materials Science and EngineeringBeihang University Laboratory of Functional Fiber Materials Institute of Bast Fiber CropsChinese Academy of Agricultural Science School of Materials Science and Engineering Jiangsu Key Laboratory for Advanced Metallic MaterialsSoutheast University Institute for Advanced Materials North China Electric Power University Center for Advanced Analysis and Computational Science Zhengzhou University

In Fe-based amorphous-/nanocrystalline ribbons,the uniformization and refinement of a-Fe grains are key aspects for optimizing their soft magnetic and mechanical ***,the Fe–P–C–B nanocrystalline alloy system was selected for *** produced as-spun ribbons with pre-existing nanocrystals through melt-quenching and then obtained a well-distributed a-Fe nanocrystalline structure through annealing below the first crystallization onset temperature （633 K）resulting in excellent magnetic properties (saturation magnetization of 1.65 T and coercivity of 1.6 A·m-1)ultra-wide annealing temperature window （from 613 to 733 K）,and extremely high annealing stability （up to 480 min at 633 K）.Furthermore,we propose a new in situ two-step mechanism for the uniformization of a-Fe nanocrystals,which is separately induced by the decomposition of the Au–P clusters and the pre-existing a-Fe nanocrystals during *** work underscores the crucial significance of micro-alloying via metastable clusters primarily influenced by metal-phosphide interactions in the process of refining a-Fe ***,i introduces a new principle for optimizing the comprehensive properties of Fe-based amorphous/nanocrystalline alloys.

关键词： Fe-based nanocrystalline alloys In-situ nano-crystallization Micro-alloying Soft magnetic property

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Nickel-catalyzed carbonylative four-component 1,4-dicarbofunctionalization of 1,3-enynes

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Science China Chemistry 2024年第6期67卷 2029-2038页

作者： Yan Zhao Qi-Chao Shan hong Xin Pin Gao Xu Yang Xin-Hua Duan Li-Na guo Department of Chemistry School of ChemistryXi’an Key Laboratory of Sustainable Energy Material Chemistry and Engineering Research Center of Energy StorageMaterials and DevicesMinistry of EducationXi’an Jiaotong UniversityXi’an710049China School of Electrical Engineering Xi’an Jiaotong UniversityXi’an710049China

An efficient Ni-catalyzed four-component 1,4-carbocarbonylation of 1,3-enynes with activated alkyl halides and arylboronic acids under atmospheric pressure of CO is *** tuning the electronic and steric effects of alkyl radicals,both electronrich and electron-deficient 1,3-enynes were compatible with this *** protocol features mild conditions,broad substrate scope,excellent functional group compatibility and facile gram-scale synthesis,providing a practical approach to the quaternary carbon center-containing allenyl *** study revealed that the acyl-NiIIspecies plays an important role in both the coupling and the alkyl radical generation processes.

关键词： Ni catalysis four-component 1 4-carbocarbonylation 1 3-enynes

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Prediction and quantification of effective gas source rocks in a lacustrine basin: Western Depression in the Liaohe Subbasin, China

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Petroleum Science 2024年第4期21卷 2218-2239页

作者： Si-Bo Yang Mei-Jun Li hong Xiao Fang-Zheng Wang guo-Gang Cai Shuang-Quan Huang State Key Laboratory of Petroleum Resources and Prospecting College of Geosciences China University of Petroleum China University of Petroleum-Beijing at Karamay College of Petroleum Research Institute of Petroleum Exploration and Development Liaohe Oilfield Company PetroChina

Due to limited data on the geochemical properties of natural gas, estimations are needed for the effective gas source rock in evaluating gas potential. However, the pronounced heterogeneity of mudstones in lacustrine successions complicates the prediction of the presence and geochemical characteristics of gas source rocks. In this paper, the Liaohe Subbasin of Northeast China is used as an example to construct a practical methodology for locating effective gas source rocks in typical lacustrine basins. Three types of gas source rocks, microbial, oil-type, and coal-type, were distinguished according to the different genetic types of their natural gas. A practical three-dimensional geological model was developed, refined, and applied to determine the spatial distribution of the mudstones in the Western Depression of the Liaohe Subbasin and to describe the geochemical characteristics(the abundance, type, and maturation levels of the organic matter). Application of the model in the subbasin indicates that the sedimentary facies have led to heterogeneity in the mudstones, particularly with respect to organic matter types. The effective gas source rock model constructed for the Western Depression shows that the upper sequence(SQ2. of the Fourth member(Mbr 4) of the Eocene Shahejie Formation(Fm) and the lower and middle sequences(SQ3 and SQ4) of the Third member(Mbr 3) form the principal gas-generating interval. The total volume of effective gas source rocks is estimated to be 586 km3. The effective microbial, oil-type, and coal-type gas source rocks are primarily found in the shallow western slope, the central sags, and the eastern slope of the Western Depression, respectively. This study provides a practical approach for more accurately identifying the occurrence and geochemical characteristics of effective natural gas source rocks, enabling a precise quantitative estimation of natural gas reserves.

关键词： Effective gas source rock 3D geological modeling Spatial distribution Geochemical characteristics Lacustrine rift basin

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Prominent removal of trace lead(Ⅱ)ions from polluted water by terephthalic acid reformed Al/Zn metal organic nanoflakes

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Particuology 2024年第1期84卷 81-88页

作者： Junhua Li Lingshu Gao Junmao hong Xiaofeng Shi Sifang Kong Jingyu Wang Hassan Algadi Benbin Xu Zhanhu guo School of Chemistry and Chemical Engineering North University of ChinaTaiyuan030051China School of Traffic&Environment Shenzhen Institute of Information TechnologyShenzhen518172China Department of Electrical Engineering Faculty of EngineeringNajran UniversityNajran11001Saudi Arabia Mechanical and Construction Engineering Faculty of Engineering and EnvironmentNorthumbria UniversityNewcastle Upon TyneNE18STUK

Terephthalic acid reformed Al/Zn metal organic nanoflake was prepared and functionalized with trie-thylamine(T-AlZn).Without adding terephthalic acid,there was no product of metal organic nanoflake.T-AlZn has a remarkable performance in removing trace lead(Ⅱ)ions(Pb^(2.)).The adsorption equipoise with the removal rate≥97%was reached within 35 *** removal rates of T-AlZn for Pb^(2.)declined by only 16.73%after four *** adsorption of T-AlZn for Pb^(2.)follows the Langmuir isotherms model and pseudo-second-order dynamics *** utmost adsorption competence was calculated as 2.5.2. mg g^(-1).The T-AlZn adsorbent exhibits a bright prospect in the adsorption for Pb^(2.)and is a considerable candidate in the disposal of industrial sewage.

关键词： Metal organic complex Nanoflake Trace level Pb^(2.) Adsorption

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Broadband and fabrication-tolerant 3-dB couplers with topological valley edge modes

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Light(Science & Applications) 2024年第8期13卷 1623-1630页

作者： guo-Jing Tang Xiao-Dong Chen Lu Sun Chao-Heng guo Meng-Yu Li Z{2.-Tao Tian Hou-{2. Chen {2.-Wei Wang Qi-Yao Sun Ying-Di Pan Xin-Tao He Yi-Kai Su Jian-Wen Dong School of Physics&State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen UniversityGuangzhou 510275China State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronic EngineeringShanghai Jiao Tong UniversityShanghai 200240China

3-dB couplers,which are commonly used in photonic integrated circuits for on-chip information processing,precision measurement,and quantum computing,face challenges in achieving robust performance due to their limited 3-dB bandwidths and sensitivity to fabrication *** address this,we introduce topological physics to nanophotonics,developing a framework for topological 3-dB *** couplers exhibit broad working wavelength range and robustness against fabrication dimensional *** leveraging valley-Hall topology and mirror symmetry,the photonic-crystal-slab couplers achieve ideal 3-dB splitting characterized by a wavelength-insensitive scattering *** analysis confirms the superiority on broad bandwidth of 48 nm and robust splitting against dimensional errors of 2. *** further propose a topological interferometer for on-chip distance measurement,which also exhibits robustness against dimensional *** extension of topological principles to the fields of interferometers,may open up new possibilities for constructing robust wavelength division multiplexing,temperature-drift-insensitive sensing,and optical coherence tomography applications.

关键词： topological splitting insensitive

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Research on the flow stability and noise reduction characteristics of quasi-periodic elastic support skin

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Defence Technology（防务技术） 2024年第3期33卷 222-236页

作者： Lu Chen Shao-gang Liu Dan Zhao Li-qiang Dong Kai Li Shuai Tang Jin Cui hong guo Department of Mechanical and Electrical Engineering Harbin Engineering UniversityHarbin150001China

To enhance flow stability and reduce hydrodynamic noise caused by fluctuating pressure,a quasiperiodic elastic support skin composed of flexible walls and elastic support elements is proposed for fluid noise *** arrangement of the elastic support element is determined by the equivalent periodic distance and quasi-periodic *** this paper,a dynamic model of skin in a fluid environment is *** influence of equivalent periodic distance and quasi-periodic coefficient on flow stability is *** results suggest that arranging the elastic support elements in accordance with the quasi-periodic law can effectively enhance flow ***,the hydrodynamic noise calculation results demonstrate that the skin exhibits excellent noise reduction performance,with reductions of 10 dB in the streamwise direction,11 dB in the spanwise direction,and 10 dB in the normal *** results also demonstrate that the stability analysis method can serve as a diagnostic tool for flow fields and guide the design of noise reduction structures.

关键词： Flow stability Quasi-period Flexible wall Elastic support element Hydrodynamic noise

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Microwave-assisted fast synthesis and red-emitting properties of a borotellurate-based phosphor with excellent thermostability

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Journal of Rare Earths 2024年第6期42卷 1036-1045,I0002页

作者： Yuefei Xiang hong Li hongzhi Zhang Lin Yang Canyuan Liao Tongsheng Yang Junpeng Li Zewen {2. Jing Zhu Key Laboratory of LCR Materials and Devices of Yunnan Province Yunnan Key Laboratory of Carbon Neutrality and Green Low-carbon TechnologiesSchool of Materials and Energy Yunnan UniversityKunming650091China

At present,with the increasing application needs of phosphor-converted white light-emitting diode(wLED),the synthetic efficiency and thermal stability of phosphor become urgent ***,this research reports a microwave-assisted fast synthesis approach to obtain a Sm^(3+)-activated borotellurate Na_(2.Y_(2.TeO_(4)(BO_(3))_(2.(NYTB)red phosphor with high crystallinity,excellent thermostability,and low chromaticity *** the NYTB-based phosphor,in contrast to the conventional solid-state synthesis,the microwave-assisted synthesis method involves lower synthesis temperature and shorter processing ***,the concentration quenching mechanism was *** w-LED device packaged with the studied phosphor exhibits a near-standard white light with proper CCT and high Ra parameters.

关键词： Borotellurate Samarium Microwave-assisted synthesis Red-emitting Thermal stability Rareearths

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Experimental Study on Vortex-Induced Vibration of Rough Risers Coupling with Interference Effect in Tandem Arrangement

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China Ocean Engineering 2024年第3期38卷 394-407页

作者： HU Ze-bo LIU Zhen LI Peng guo Hai-yan REN Xiao-hui HOU Hao HAO Lian-hong College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China Qingdao Key Laboratory of Marine Civil Engineering Materials and Structures Qingdao 266590China College of Engineering Ocean University of ChinaQingdao 266100China

In order to study the response law of vortex-induced vibration(VIV)of marine risers under the combined action of roughness and interference effects,and to reveal the coupling mechanism of roughness and interference effects on the riser,a VIV experiment of rough risers in tandem arrangement was conducted in a wave−current combined *** experiment characterized the risers’roughness by arranging different specifications of attachments on the surface of the *** rough risers with different roughness and smooth risers were arranged in tandem arrangement,with the rough risers arranged *** experimental results indicate that the suppression of the attachments on the downstream risers’vibration are more significant both in the CF and IL directions as the reduced velocity *** the downstream riser,the amplitude response of rough riser is more significantly weakened compared with the smooth one at high reduced *** the upstream risers,changes in the roughness and spacing ratio have an impact on their‘lock-in’*** the roughness of downstream risers is relatively large(0.1300)and the spacing between risers is small(S/D=4.0),the reduced velocity range of‘lock-in’region in the CF direction of upstream risers is obviously expanded,and the displacement in the‘lock-in’region is severer.

关键词： marine riser vortex-induced vibration tandem arrangement roughness interference effect

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