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Journal of Environmental Sciences 2024年第8期142卷 115-128页

作者： Yijun Duan Fang liu Xiang liu Miao Li School of Environment Tsinghua UniversityBeijing 100084China Transportation Institute of Inner Mongolia University Hohhot 010070China

Microscale zero-valent iron(mZVI)has shown great potential for groundwater Cr(Ⅵ)***,low Cr(Ⅵ)removal capacity caused by passivation restricted the wide use of *** prepared mZVI/GCS by encapsulating mZVI in a porous glutaraldehydecrosslinked chitosan matrix,and the formation of the passivation layer was alleviated by reducing the contact between zero-valent iron *** average pore diameter of mZVI/GCS was 8.775 nm,which confirmed the mesoporous characteristic of this *** of batch experiments demonstrated that mZVI/GCS exhibited high Cr(Ⅵ)removal efficiency in a wide range of pH(2-10)and temperature(5-35℃).Common groundwater coexisting ions slightly affected m ZVI/*** material showed great reusability,and the average Cr(Ⅵ)removal efficiency was 90.41%during eight *** this study,we also conducted kinetics and isotherms ***-second-order model was the most matched kinetics *** Cr(Ⅵ)adsorption process was fitted by both Langmuir and Freundlich isotherms models,and the maximum Langmuir adsorption capacity of m ZVI/GCS reached243.63 mg/g,which is higher than the adsorption capacities of materials reported in most of the previous ***,the column capacity for Cr(Ⅵ)removal of a mZVI/GCS-packed column was 6.4 times higher than that of a mZVI-packed column in a 50-day ***,mZVI/GCS with a porous structure effectively relieved passivation problems of mZVI and showed practical application prospects as groundwater Cr(Ⅵ)remediation material with practical application prospects.

关键词： Chitosan Glutaraldehyde mZVI Cr(Ⅵ) Groundwater

Time-history performance optimization of flapping wing motion using a deep learning based prediction model

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Chinese Journal of Aeronautics 2024年第5期37卷 317-331页

作者： Tianqi WANG liu liu Jun LI Lifang ZENG School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310027China Huanjiang Laboratory Zhuji 311800China

Flapping Wing Micro Aerial Vehicles(FWMAVs)have caused great concern in various fields because of their high efficiency and *** wing motion is a very important factor that affects the performance of the aircraft,and previous works have always focused on the time-averaged performance ***,the time-history performance is equally important in the design of motion mechanism and flight control *** this paper,a time-history performance optimization framework based on deep learning and multi-island genetic algorithm is presented,which is designed in order to obtain the optimal two-dimensional flapping wing ***,the training dataset for deep learning neural network is constructed based on a validated computational fluid dynamics *** aerodynamic surrogate model for flapping wing is obtained after the convergence of *** surrogate model is tested and proved to be able to accurately and quickly predict the time-history curves of lift,thrust and ***,the optimization framework is used to optimize the flapping wing motion in two specific cases,in which the optimized propulsive efficiencies have been improved by over 40%compared with the ***,a dimensionless parameter C_(variation)is proposed to describe the variation of the time-history characteristics,and it is found that C_(variation)of lift varies significantly even under close time-averaged *** the importance of time-history performance in practical applications,the optimization that integrates the propulsion efficiency as well as C_(variation)is carried *** final optimal flapping wing motion balances good time-averaged and time-history performance.

关键词： FWMAV Flapping wing motion Deep learning Unsteady aerodynamic performance Optimization Time-history curve

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世界水产品绿色养殖比较研究及对中国启示

海洋开发与管理 2022年第3期39卷 51-55页

作者：刘华楠赵昕怡上海海洋大学经济管理学院上海201306

当前全球渔业捕捞量已接近顶峰局势,水产养殖发展面临巨大环境压力,水产品绿色养殖能满足消费者对优质蛋白需求的同时,还能有效缓解生态问题,保证食品质量安全。水产品养殖绿色发展已成为世界各国的共识,渔业发达国家在一定程度上已形... 详细信息

当前全球渔业捕捞量已接近顶峰局势,水产养殖发展面临巨大环境压力,水产品绿色养殖能满足消费者对优质蛋白需求的同时,还能有效缓解生态问题,保证食品质量安全。水产品养殖绿色发展已成为世界各国的共识,渔业发达国家在一定程度上已形成较完善的绿色水产养殖体系。文章基于全球水产业发展现状和趋势,通过研究欧盟、美国和日本水产品绿色养殖的相关经验,最后结合中国水产养殖业发展现状,提出在建立严格认证标准的基础上,国内政府应加强对“绿色水产品”消费的正确引导;借鉴别国对渔业可持续发展的政策和管理制度;注重关键科学技术的研发,做到产学结合;保障资金的有效投入等相关政策建议。

关键词：水产品绿色养殖食品质量安全中国启示

维普期刊数据库博看期刊

Towards cultivar-oriented gene discovery for better crops

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The Crop Journal 2024年第3期12卷 670-675页

作者： Dengcai liu Triticeae Research Institute Sichuan Agricultural UniversityChengdu 611130SichuanChina

The continued expansion of the world population,increasingly inconsistent climate and shrinking agricultural resources present major challenges to crop ***,the increasing ability to discover and manipulate genes creates new opportunities to develop more productive and resilient *** genes have been described in papers as being beneficial for yield ***,few of them have been translated into increased yield on *** contrast,commercial breeders are facing gene decidophobia,i.e.,puzzled about which gene to choose for breeding among the many identified,a huge chasm between gene discovery and cultivar *** purpose of this paper is to draw attention to the shortfalls in current gene discovery research and to emphasise the need to align with cultivar *** methodology dictates that genetic studies not only focus on gene discovery but also pay good attention to the genetic backgrounds,experimental validation in relevant environments,appropriate crop management,and data *** close of the gaps should accelerate the application of molecular study in breeding and contribute to future global food security.

关键词： Cultivar innovation Data reusability Gene discovery Gene decidophobia Omnigenic model

Thermoregulatory molecular sieving in crystals

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Science China Materials 2024年第10期67卷 3419-3420页

作者： Guozhen liu Wanqin Jin Gongping liu State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211800China

Sub-nanometer channels for the selective recognition of the components in chemical mixtures from others play a crucial role in the adsorption and membrane separation[1].It remains a grand challenge to separate small m... 详细信息

关键词： structure. molecular separation

Breakdown of effective medium theory:A study of photonic spin Hall effect in deep-subwavelength all-dielectric multilayers

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 173-174页

作者： Yongmin liu Department of Mechanical and Industrial Engineering Northeastern UniversityBoston 02115USA Department of Electrical and Computer Engineering Northeastern UniversityBoston 02115USA

Effective medium theory(EMT)has been widely applied in material science,electromagnetics and photonics to determine the effective material properties for inhomogeneous composites comprising subwavelength *** versatility of this foundational approach has been established through its application in classical Maxwell-Garnet models,which encompass relatively simple structures。

关键词： composites theory dielectric

Fatigue-resistant sliding ferroelectricity

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Science China Materials 2024年第10期67卷 3417-3418页

作者： Zheng liu School of Materials Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore

The direction of spontaneous polarization in ferroelectricity can be reoriented by an external electric *** special feature of ferroelectricity is important candidates for fabricating advanced nonvolatile random-access memory[1].However,repeatedly switching polarization induces the ferroelectric device performance degenerates due to a reduction of polarization.

关键词： polarization ferroelectric field.

A REFINEMENT OF THE SCHWARZ-PICK ESTIMATES AND THE CARATHéODORY METRIC IN SEVERAL COMPLEX VARIABLES

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Acta Mathematica Scientia 2024年第4期44卷 1337-1346页

作者： Xiaosong liu Taishun liu School of Mathematics and Statistics Lingnan Normal UniversityZhanjiang 524048China Department of Mathematics Huzhou UniversityHuzhou 313000China

In this article,we first establish an asymptotically sharp result on the higher order Fréchet derivatives for bounded holomorphic mappings f(x)=f(0)+∞∑s=1Dskf(0)(x^(sk))/(sk)!:B_(X)→B_(Y),where B_X is the unit ball of *** next give a sharp result on the first order Fréchet derivative for bounded holomorphic mappings F(X)=F(0+)∞∑s=KD^(s)f(0)(x^(8)/s!):B_(X)→B_(Y),where B_(X)is the unit ball of *** results that we derive include some results in several complex variables,and extend the classical result in one complex variable to several complex variables.

关键词： refined Schwarz-Pick estimate bounded holomorphic mapping Carathéodory metric first order Fréchet derivative higher order Fréchet derivatives

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新颖性、创造性审查过程中的举证责任分析

中国发明与专利 2019年第6期16卷 100-103页

作者：丁雪龙刘华楠国家知识产权局专利局专利审查协作河南中心

谈及举证责任分配,最常谈及的就是“谁主张谁举证”,在民事诉讼法中,关于证明责任的分配有一般原则和具体情形下的举证责任分配,但是在专利实质审查过程中,关于审查员提出的、用以证明申请方案不具备新颖性、创造性的对比文件是否为现... 详细信息

谈及举证责任分配,最常谈及的就是“谁主张谁举证”,在民事诉讼法中,关于证明责任的分配有一般原则和具体情形下的举证责任分配,但是在专利实质审查过程中,关于审查员提出的、用以证明申请方案不具备新颖性、创造性的对比文件是否为现有技术的举证责任问题并没有很明确。本文借由对民诉法、行政诉讼法中的举证责任分配的简单梳理,以相关案例的处理方式进行分析,提出在新颖性、创造性审查过程中较为合理的举证责任分配和处理程序。

关键词：专利审查新颖性创造性证据举证责任

The important role of Turbidity Maximum Zone in sedimentary dynamic of estuarine mangrove swamp

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Frontiers of Earth Science 2024年第1期18卷 219-226页

作者： Tao liu Ying liu Baoqing HU Key laboratory of Environment Change and Resources Use in Beibu Gulf(Ministry of Education) Nanning Normal UniversityNanning 530001China School of Civil Engineering and Architecture Guangxi UniversityNanning 530004China

Sedimentation is a key process affecting wetland sustainability and carbon burial *** context of sea level rise,climate change and human activities,further understanding about the sedimentary dynamic in wetland is critical in predicting the landscape evolution or the change in carbon burial *** this study,based on the field hydrological observation in a mangrove system in the Nanliu River estuary,we found the net flux of suspended sediment to mangrove is 39−72 kg/m in tidal cycles with Turbidity Maximum Zone(TMZ)forming in surface layer and only is 9−18 kg/m in tidal cycles without *** higher net flux of suspended sediment to mangrove in tidal cycles with TMZ forming in surface layer is attributed to high SSC in rising tide and intense flocculation in *** significant discrepancy in sedimentation rate in the mangrove patches also can be explained by the probability of TMZ forming in the surface layer of *** future,rapid sea level rising may lead to the change of TMZ pattern in estuary,which will result in non-negligible variation in sedimentation rate in *** to the present data of sedimentation rate in wetlands,the fragility of wetlands in river estuary may be miscalculated.

关键词： mangrove wetland sedimentation Turbidity Maximum Zone Nanliu River