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Morphological and phylogenetic diversity of magnetotactic bacteria and multicellular magnetotactic prokaryotes from a mangrove ecosystem in the Sanya River,South China

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Journal of Oceanology and Limnology 2021年第6期39卷 2015-2026页

作者： haitao chen Jinhua LI Long-Fei WU Wei-Jia ZHANG Beijing Key Laboratory of Biological Electromagnetism Institute of Electrical EngineeringChinese Academy of SciencesBeijing 100190China France-China Joint Laboratory for Evolution and Development of Magnetotactic Multicellular Organisms Chinese Academy of SciencesBeijing 100029China Deep-Sea Microbial Cell Biology Department of Deep Sea SciencesInstitute of Deep-Sea Science and EngineeringChinese Academy of SciencesSanya 572000China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China LCB Aix Marseille UniversityCNRSMarseille 13402France

Magnetotactic bacteria(MTB)are morphologically and phylogenetically diverse prokaryotes commonly able to produce magnetic nanocrystals within intracellular membrane-bound organelles(i.e.,magnetosomes)and to swim along geomagnetic field *** studied the diversity of MTB in the samples collected from a mangrove area in the Sanya River,Hainan,South China,using microscopic and microbial phylogenetic *** of microanalysis and observation in microscopy and energy dispersive X-ray spectroscopy(EDXS)reveal a highly morphological diversity of MTB including unicellular cocci,vibrios,rod-shaped bacteria,and three morphotypes of multicellular magnetotactic prokaryotes(MMPs).In addition,analysis of the 16S rRNA gene showed that these MTB were clustered into 16 operational taxonomic units affi liated to the Alpha-,Delta-,and Gamma-proteobacteria classes within the Proteobacteria ***,by using the coupled fluorescence and transmission electron microscopy analysis,rodshaped bacteria,vibrio,and cocci were phylogenetically and structurally identified at the single-cell *** study demonstrated highly diverse MTB communities in the mangrove ecosystem and provide a new insight into the overall diversity of MTB.

关键词： magnetotactic bacteria diversity magnetosome phylogenetic analysis coordinated fl uorescence in-situ hybridization transmission electron microscopy(FISH-TEM) mangrove

Waveguide-integrated optical modulators with two-dimensional materials

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Journal of Semiconductors 2023年第11期44卷 8-25页

作者： haitao chen Hongyuan Cao Zejie Yu Weike Zhao Daoxin Dai State Key Laboratory for Modern Optical Instrumentation College of Optical Science and EngineeringInternational Research Center for Advanced PhotonicsZhejiang UniversityZijingang CampusHangzhou 310058China College of Advanced Interdisciplinary Studies&Hunan Provincial Key Laboratory of Novel Nano-Optoelectronic Information Materials and Devices National University of Defense TechnologyChangsha 410073China Nanhu Laser Laboratory National University of Defense TechnologyChangsha 410073China Ningbo Research Institute Zhejiang UniversityNingbo 315100China

Waveguide-integrated optical modulators are indispensable for on-chip optical interconnects and optical *** cope with the ever-increasing amount of data being generated and consumed,ultrafast waveguide-integrated optical modulators with low energy consumption are highly *** recent years,two-dimensional(2D)materials have attracted a lot of attention and have provided tremendous opportunities for the development of high-performance waveguide-integrated optical modulators because of their extraordinary optoelectronic properties and versatile *** paper reviews the state-of-the-art waveguide-integrated optical modulators with 2D materials,providing researchers with the developing trends in the field and allowing them to identify existing challenges and promising potential ***,the concept and fundamental mechanisms of optical modulation with 2D materials are ***,a review of waveguide-integrated optical modulators employing electro-optic,all-optic,and thermo-optic effects is ***,the challenges and perspectives of waveguide-integrated modulators with 2D materials are discussed.

关键词： optical modulation two-dimensional(2D)materials on-chip waveguide

Microstructure and Mechanical Properties of Nickel‑Aluminum Bronze Coating on 17‑4PH Stainless Steel by Laser Cladding

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Chinese Journal of Mechanical Engineering 2022年第6期35卷 403-414页

作者： Lu Zhao Baorui Du Jun Yao haitao chen Ruochen Ding Kailun Li Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Shenyang Dalu Laser Advanced Manufacturing Technology Innovation Co.Ltd Shenyang 110000China Institute of Science and Technology China Three Gorges CorporationBeijing 100038China

Bimetallic copper-steel composite could be an effective structural material to improve the performance of traditional nickel-aluminum bronze(NAB)ship propeller due to its high structural strength and corrosion *** this work,the defect-free NAB coatings has been successfully fabricated by laser direct depositing technique on the 17-4PH stainless steel *** phase constitution,microstructure characteristics and hardness properties were investigated in *** XRD results showed that the coatings mainly consisted ofα-Cu,Fe and intermetallicκphases despite the diffraction peaks shifted more than 0.5°,which may due to the influence of the Ni,Fe and Al atoms dissolved into *** microstructures of the coatings were affected significantly by laser energy density according to SEM and EDS *** top region of the coating was more undercooled during solidification,therefore the grains at this region was much finer than that at the bottom *** higher energy input would lead to coarser ***-rich dendrites and spherical particles were found in the Cu matrix,which could be a result of liquid *** hardness of the coating is in the range of 204 HV0.2–266 HV0.2 which is higher than traditional as-cast *** uneven distribution of Fe-rich phases as well as the hardκphases could be the main reasons for the fluctuations of the hardness *** fracture occurred at bronze side,not at transition zone,which shows there is a good interfacial bonding between the two metals produced by laser cladding.

关键词： Laser direct depositing Nickel-aluminum bronze Microstructure Hardness Tensile Liquid separation

Preparation of Cellulose Nanofibrils by Multi-Site Regioselective Oxidation

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Journal of Renewable Materials 2020年第10期8卷 1269-1282页

作者： Liying Song Xixiang Pei Rui Li haitao chen Xiaozheng Sun College of Engineering Northeast Agricultural UniversityHarbin150030China Harbin Botai Biological Technology Co. Ltd.Harbin150030China

Cellulose nanofibrils(CNFs)are promising sustainable materials that can be applied to nanocomposites,as well as medical and life-sciences ***,methods for the preparation of these important materials are energy intensive because heating and mechanical disintegration are required to produce cellulose fibers below 100 nm in *** this study,CNFs were prepared through the multi-site regioselective oxidation of cellulose with 2,2,6,6-tetramethylpiperidine-1-oxyl(TEMPO)and periodate at room temperature(20–25°C),without any mechanical-disintegration *** electron microscopy(TEM)revealed that the CNFs had the average widths of 14.1,55.4,and 81.9 nm for three different ***-transform infrared spectroscopy revealed that carboxyl groups were created on the surfaces of the microfibrils,while X-ray diffraction studies showed that the cellulose I structure was maintained after oxidation,and that the cellulose nanofibril crystallinity index exceeded 70%.These results demonstrate that CNFs can be prepared by multi-site regioselective oxidation at room temperature in the absence of mechanical disin*** addition,a model was developed to calculate the total content of carboxylate and aldehyde groups of CNFs prepared by the TEMPO mediate oxidation,the periodate oxidation,and the multi-site regioselective oxidation methods based on the particle width determined by *** calculated values of the model were in good agreement with the total content(experimental value)of carboxylate and aldehyde groups of CNFs prepared by the TEMPO-mediated oxidation and the multi-site regioselective oxidation ***,the model was not valid for CNFs prepared by the periodate oxidation method.

关键词： Cellulose nanofibril multi-site regioselective oxidation total content of carboxylate and aldehyde groups particle width

Influences of mechanized tillage and sowing modes on soil physical properties,soybean yield and economic benefits in mollisols region of Northeast China

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 130-139页

作者： haitao chen Jian Sun Yiming Zhang Jinyou Qiao College of Engineering Northeast Agricultural UniversityHarbin 150030China Heilongjiang Province Technology Innovation Center of Mechanization and Materialization of Major Crops Production Harbin 150030China College of Mechanical and Electrical Engineering East University of HeilongjiangHarbin 150066China

Appropriate mechanized straw returning and tillage sowing techniques were effective means to optimize soil physical properties and enhance agricultural productivity,as well as important measures for the conservation and restoration of mollisols region in Northeast *** the condition of full-scale maize straw returning,four mechanized tillage and sowing modes were set,including plough tillage and sowing(PTS),combined tillage and sowing(CTS),no-tillage and sowing(NTS),and no-tillage and sowing with straw mulching(NTSM).In 2020 and 2021,the study investigated the effects of different mechanized tillage and sowing modes on soil physical properties,soybean yield and economic *** results showed that during the pod-setting and pod-filling period of soybean,the NTS and NTSM treatments exhibited better effects on deep soil insulation and shallow soil moisture retention,the soil physical structure of PTS and CTS treatments were relatively *** with PTS and CTS treatments,NTS and NTSM treatments significantly increased soil gravimetric water content(SWC)by 2.35%to 7.98%in the 5-15 cm soil layer and increased soil temperature(ST)by 3.94%to 10.42%in the 25-35 cm soil layer(p0.05),the soybean yield of NTSM treatment in 2021 significantly increased by 7.30%and 5.84%over PTS and CTS treatments,*** the average annual profit per unit area of NTSM treatment increased by 12.84%,12.41%and 8.57%compared with PTS,CTS and NTS treatments,***,it was recommended to combine NTS

关键词： mechanized tillage and sowing modes full-scale straw returning soil physical properties soybean yield economic benefits mollisols conservation

Reflection behavior of insensitive explosive detonation propagating around a cylinder

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Acta Mechanica Sinica 2024年第7期40卷 55-65页

作者： Zixuan Zhang Yuan Wang Xiaomian Hu haitao chen Institute of Applied Physics and Computational Mathematics Beijing 100094China Graduate School of China Academy of Engineering Physics Beijing 100088China

Insensitive explosive detonation has wide applications in compressing and driving inert materials,and thereby the interaction between detonation and inert materials has received more *** this paper,a two-dimensional numerical simulation based on the Euler multiphase flow framework is used to investigate the reflection behavior of the insensitive explosive detonation propagating around a *** results show that there is a critical incident angle,defined as transition angle for detonation propagating around the cylinder,below which the regular reflection(RR)on the cylinder surface is *** the incident angle is greater than the transition angle,RR changes to Mach *** transition angle is larger than that obtained by polar curve theory and the change of incident angle is used to interpret above *** addition,the influence of cylindrical radius and detonation reaction zone width on the reflection behavior is *** the cylindrical radius increases,the height of Mach stem increases while the transition angle decreases and gradually approaches the value in pole curve *** Neumann reflection is observed when the reaction zone width is relatively *** is because the energy release rate in the reaction zone is high for small reaction zone width,resulting in the formation of a series of compression waves near the cylindrical interface.

关键词： Insensitive explosive detonation Cylindrical inert material Reflection behavior

THE OPTICAL PROPERTIES OF THE LASER BEAM PASSED THROUGH A TURBULENT SHEAR LAYER

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Acta Mechanica Sinica 1987年第3期3卷 214-222页

作者： chen haitao (Institute of Mechanics,Academia Sinica) 1. Institute of Mechanics Academia Sinica Taiwan

The related fluid dynamic theory,experimental device and some preliminary results of thestudy of the optical properties of a laser beam passed through a turbulent shear layer are *** of image processing for the determination of the optical density from a intederogram by means of aMicroneye Bullet and a Microcomputer is also described.

关键词： optical property laser beam quality turbulent shear layer interferogram image processing

Adsorption Properties and Cost of Dicarboxylic Nanocellulose on Copper Ions for Wastewater Treatment

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Journal of Renewable Materials 2022年第3期10卷 751-766页

作者： Xiaozheng Sun Yu Yang Qiang He Jianye Li Rui Li haitao chen College of Engineering Northeast Agricultural UniversityHarbin150030China College of Mechanical Engineering Jiamusi UniversityJiamusi154007China

The accumulation of Cu^(2+)in water is a potential threat to human health and *** nano-cellulose(DNC)with rich carboxyl groups was prepared through the NaIO_(4)–NaClO_(2) sequential oxidation meth-od to efficiently remove copper ions,and the Cu 2+adsorption properties and cost were *** maximum adsorption capacity reached 184.2 mg/g at pH 6 and an adsorbent dose of 5 g/***,the maximum adsorption capacities of monocarboxylic nanocellulose(MNC),DNC,and tricarboxylic nanocellulose(TNC)with carboxyl groups as the main adsorption sites were calculated to be 228.7,261.3,and 148.1 mg/g,*** Cu^(2+)adsorption costs of MNC,DNC,and TNC were calculated and compared with those of powdered activated carbon(PAC).The Cu^(2+)adsorption capacity of DNC is higher than that of PAC,and the adsorption cost is close to or lower than that of PAC,demonstrating that the DNC prepared by sequential oxidation of NaIO_(4)–NaClO_(2) has competitive adsorption capacity and cost in the treatment of wastewater containing Cu^(2+).

关键词： Nanocellulose heavy metal ions maximum adsorption capacity adsorption cost

The Impact of Aqueous Medium on Gas Yields and Kinetic Behaviors of Hydrogen Isotope Fractionation during Organic Matter Thermal Degradation

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Acta Geologica Sinica(English Edition) 2011年第6期85卷 1466-1477页

作者： LU Shuangfang WANG Min XUE haitao LI Jijun chen Fangwen XU Qingxia Northeast Petroleum University Heilongjiang Province 163318 China

In order to recognize the impact of aqueous medium on gas yields and the kinetic behaviors of hydrogen isotope fractionation during organic matter thermal degradation, the gold tube apparatus was used to conduct thermal simulation experiments by mixing the nC18 with the water of different properties and proportions. The yields of natural gas components, the relation among hydrogen isotope composition of each component and the experimental temperatures vs. heating rates have been obtained, and the results indicate that under the higher temperature conditions, the hydrous experiment has obvious impact on gas yields, such as when more water is added, higher amounts of hydrocarbon gas and H2 are yielded, and the existence of water obviously prolongs the temperature interval with the existence of heavy hydrocarbon gas. It also shows that the hydrogen isotope of hydrocarbon gas generated by the hydrous experiment is obviously lighter than that generated by the anhydrous experiment, and with the increasing amount of added water, the δD value of hydrocarbon gas gradually decreases. Compared with gas yields, the variation of δD value is more sensitive to aqueous medium in the thermal simulation experiment. However, compared with the amount of the added water, the aqueous medium property has smaller impact on the gas yields, which still shows the inherit effect on hydrogen isotope composition of aqueous medium. Through the model simulation and the isotope fractionation behavior analysis, it is validated that the hydrogen isotope fractionation process can be well described by the chemical kinetic model. The difference of reaction fraction of normal methane and D-containing methane is large, corresponding to the same activation energy. The content of normal methane is obviously higher in the part with lower activation energy, while the content of D-containing methane is higher in the part with higher activation energy. Therefore, it will result in larger hydrogen isotope fracti

关键词： hydrogen isotope fractionation chemical kinetics nC18 gas generation hydrous experiment