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A bulk extraction method to determine the stable isotope ratios of iron,nickel,copper,zinc,and cadmium in seawater using multi-collector inductively coupled plasma mass spectrometry

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Acta Oceanologica Sinica 2024年第7期43卷 125-137页

作者： Zhan Shen Yuncong Ge Jiahui Liu Wenkai Guan wenfeng hu Ruifeng Zhang School of Oceanography Shanghai Jiao Tong UniversityShanghai 200030China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519015China Shanghai Key Laboratory of Polar Life and Environment Sciences Shanghai Jiao Tong UniversityShanghai 200030China Key Laboratory of Polar Ecosystem and Climate Change of Ministry of Education Shanghai Jiao Tong UniversityShanghai 200030China Laboratory for Polar Science Polar Research Institute of ChinaMinistry of Natural ResourcesShanghai 200136China

The oceanic trace metals iron(Fe),nickel(Ni),copper(Cu),zinc(Zn),and cadmium(Cd)are crucial to marine phytoplankton growth and global carbon cycle,and the analysis of their stable isotopes can provide valuable insights into their biogeochemical cycles within the ***,the simultaneous isotopic analysis of multiple elements present in seawater is challenging because of their low concentrations,limited volumes of the test samples,and high salt *** this study,we present the novel method developed for the simultaneous analysis of five isotope systems by 1 L seawater *** the developed method,the NOBIAS Chelate-PA1 resin was used to extract metals from seawater,the AG MP-1M anion-exchange resin to purify Cu,Fe,Zn,Cd,and the NOBIAS Chelate-PA1 resin to further extract Ni from the matrix ***,a multi-collector inductively coupled plasma mass spectroscope(MC-ICPMS)was employed for the isotopic measurements using a doublespike technique or sample-standard bracketing combined with internal *** method exhibited low total procedural blanks(0.04 pg,0.04 pg,0.21 pg,0.15 pg,and 3 pg for Ni,Cu,Fe,Zn,and Cd,respectively)and high extraction efficiencies(100.5%±0.3%,100.2%±0.5%,97.8%±1.4%,99.9%±0.8%,and 100.1%±0.2%for Ni,Cu,Fe,Zn,and Cd,respectively).The external errors and external precisions of this method could be considered *** proposed method was further tested on the seawater samples obtained from the whole vertical profile of a water column during the Chinese GEOTRACES GP09 cruise in the Northwest Pacific,and the results showed good agreement with previous related *** innovative method will contribute to the advancement of isotope research and enhance our understanding of the marine biogeochemical cycling of Fe,Ni,Cu,Zn,and Cd.

关键词： trace metal stable isotopes seawater bulk extraction

Adaptable "bubble particles" prepared by green aqueous phase reshaping for completely removing odor

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Nano Research 2024年第3期17卷 2172-2180页

作者： Jiajia Ma Yichang Xia Tienan Zhao wenfeng hu Weifeng Zhang Qinfei Ke Yi Zhao Shanghai Frontiers Science Center of Advanced Textiles Donghua UniversityShanghai 201620China Engineering Research Center of Technical Textiles Ministry of EducationDonghua UniversityShanghai 201620China School of Fashion Engineering Central Laboratory Shanghai University of Engineering ScienceShanghai 201620China Department of Materials Science and Engineering National University of SingaporeSingapore 117575Singapore School of Perfume and Aroma Technology Shanghai Institute of TechnologyShanghai 201418China

Facile and ecofriendly loading of micro/nano function-specific substances to create functional materials is a trend being pursued by ***,current micro/nano particles loading approaches are often hindered by issues such as uneven distribution,unsatisfactory stability and complicate *** this work,we present an aqueous phase reshaping method that only utilizes the moisture to fabricate the"bubble particles",which could perfectly cater to the topography of the *** green preparation of bubble particles adopts an absolutely zero-pollution method,realizing the firm loading of particles on the *** the preparation and loading of particles overcomes the traditional complicate process,while the aqueous phase reshaping ensures uniform and firm loading of the"bubble particles"onto the *** mechanism demonstrates a significant enhancement in the interface relation after aqueous phase reshaping,with a 121-fold increase in contact surface area achieved by reducing the height by 1μ***,we explore for the first time the influence of the nature of the receiving substrate on the interface morphology of particles during electrostatic spraying,which has important guiding significance for the interface relationship of electrostatic spraying and even electrostatic spinning *** also screen out the natural antibacterial essential oil linalool as the effective specialized antibacterial agent,which can specifically inhibit the odor-producing Proteus in urine,with an antibacterial rate of up to 100%.Taken together,this simple,ecofriendly method for fabricating functional materials with optimal interface stability appears highly promising for use in various products formed by electrostatic spraying/spinning.

关键词： bubble particle electrostatic spraying aqueous phase reshaping interface bonding remove odor nano spraying

Surface energy and water vapor fluxes observed on a megadune in the Badain Jaran Desert, China

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Journal of Arid Land 2015年第5期7卷 579-589页

作者： hu wenfeng WANG Nai'ang ZHAO Liqiang NING Kai ZHANG Xunhe SUN Jie Center for Climate Change and Hydrologic Cycle in Arid Region College of Earth and Environmental Science Lanzhou University College of Geographical Science and Tourism Xinjiang Normal University

The Badain Jaran Desert is the second-largest area of shifting sands in China. Our first measurements of the energy components and water vapor fluxes on a megadune using eddy covariance technology were taken from April 2012 to April 2013. The results indicate that the Iongwave and shortwave radiative fluxes exhibited large fluctuations and seasonal dynamics. The total radiative energy loss by Iongwave and shortwave radiation was greater on the megadune than from other underlying surfaces. The radiation partitioning was different in different seasons. The land-atmosphere interaction was primarily represented by the sensible heat flux. The average sensi- ble heat flux （40.1 W/m2） was much larger than the average latent heat flux （14.5 W/m2）. Soil heat flux played an important role in the energy balance. The mean actual evaporation was 0.41 mm/d, and the cumulative actual evaporation was approximately 150 mm/a. The water vapor would transport downwardly and appear as dew con- densation water. The amount of precipitation determined the actual evaporation. The actual evaporation was sup- posed to be equal to the precipitation on the megadune and the precipitation was difficult to recharge the ground- water. Our study can provide a foundation for further research on land-atmosphere interactions in this area.

关键词： eddy covariance technology energy and water vapor fluxes precipitation evaporation

Handling the Challenges of Small-Scale Labeled Data and Class Imbalances in Classifying the N and K Statuses of Rubber Leaves Using Hyperspectroscopy Techniques

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Plant Phenomics 2024年第2期6卷 281-294页

作者： wenfeng hu Weihao Tang Chuang Li Jinjing Wu Hong Liu Chao Wang Xiaochuan Luo Rongnian Tang School of Mechanical and Electrical Engineering Hainan UniversityHaikou 570228China School of Electrical Engineering and Automation Tianjin UniversityTianjin 300072China

The nutritional status of rubber trees(Hevea brasiliensis)is inseparable from the production of natural ***(N)and potassium(K)levels in rubber leaves are 2 crucial criteria that reflect the nutritional status of the rubber *** hyperspectral technology can evaluate N and K statuses in leaves ***,high bias and uncertain results will be generated when using a small size and imbalance dataset to train a spectral estimaion model.A typical solution of laborious long-term nutrient stress and high-intensive data collection deviates from rapid and flexible advantages of hyperspectral ***,a less intensive and streamlined method,remining information from hyperspectral image data,was assessed.

关键词： handling data ersp challenges classifying imbalances labeled leaves rubber small-scale

Eddy covariance measurements of water vapor and energy flux over a lake in the Badain Jaran Desert,China

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Journal of Arid Land 2018年第4期10卷 517-533页

作者： SUN Jie hu wenfeng WANG Nai'ang ZHAO Liqiang AN Ran NING Kai ZHANG Xunhe College of Earth and Environmental Sciences Center for Desert and Arid Region ResearchLanzhou JniversityLanzhou 730000China Center for Central Asian Atmosphere Science Research Urumqi 830002China Fuyang Normal University Fuyang 236037China

Exploring the surface energy exchange between atmosphere and water bodies is essential to gain a quantitative understanding of regional climate change, especially for the lakes in the desert. In this study, measurements of energy flux and water vapor were performed over a lake in the Badain Jaran Desert, China from March 2012 to March 2013. The studied lake had about a 2-month frozen period （December and January） and a 10-month open-water period （February-November）. Latent heat flux （LE） and sensible heat flux （Hs） acquired using the eddy covariance technique were argued by measurements of long＇wave and shortwave radiation. Both fluxes of longwave and shortwave radiation showed seasonal dynamics and daily fluctuations during the study period. The reflected solar radiation was much higher in winter than in other seasons. LE exhibited diurnal and seasonal variations. On a daily scale, LE was low in the morning and peaked in the afternoon. From spring （April） to winter （January）, the diurnal amplitude of LE decreased slowly. LE was the dominant heat flux throughout the year and consumed most of the energy from the lake. Generally speaking, LE was mostly affected by changes in the ambient wind speed, while Hs was primarily affected by the product of water-air temperature difference and wind speed. The diurnal LE and Hs were negatively correlated in the open-water period. The variations in Hs and LE over the lake were differed from those on the nearby land surface. The mean evaporation rate on the lake was about 4.0 mm/d over the entire year, and the cumulative annual evaporation rate was 1445 mm/a. The cumulative annual evaporation was 10 times larger than the cumulative annual precipitation. Furthermore, the average evaporation rates over the frozen period and open-water period were approximately 0.6 and 5.0 mm/d, respectively. These results can be used to analyze the water balance and quantify the source of lake water in the Badain Jaran Desert.

关键词： eddy covariance energy flux radiation evaporation precipitation lake Badain Jaran Desert

Exploration of BD2/SINS Deeply Integrated Navigation in CZ-7 Launch Vehicle Guidance System

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Exploration of BD2/SINS Deeply Integrated Navigation in CZ-7...

Effect of Lactobacillus salivarius H strain isolated from Chinese dry-cured ham on the color stability of fresh pork

第五届中国卫星导航学术年会

作者： TANG Yi ZHONG Wenan SHOU Junming hu wenfeng Unit 63810

ISBN: (纸本)9783642547393

Long March 7（CZ-7） launch vehicle is China’s new generation of non-toxic,non-polluting,high performance,low cost and high thrust medium launch vehicle *** an important part of launch vehicle flight control system,the main function of the guidance system is to control the center of mass motion using the motion parameters provided by navigation system,ensure that the launch vehicle along a predetermined *** present,CZ-7 launch vehicle guidance system used global navigation satellite system（GNSS） and the strapdown inertial navigation system（SINS） loosely integrated navigation *** the first flight phase of launch vehicle,the positioning antenna of satellite receiver disturbed largely,and launch vehicle injection accuracy is decided by the guidance accuracy of second flight phase,thus GNSS/SINS loosely integrated navigation mode used only in the second flight phase of launch *** order to further improve injection accuracy of CZ-7 launch vehicle,the BD2/SINS deeply integrated which applied in the CZ-7 launch vehicle guidance system are discussed in this *** system structure and applicability condition for BD2/SINS deeply integrated navigation are analysis briefly in the paper,based on the new characteristics of CZ-7 launch *** research results can provide a theoretical basis and technical support for the new launch vehicle guidance system.

关键词： BD2 strapdown inertial navigation system deeply integrated navigation launch vehicle guidance system

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Food Science and human Wellness 2013年第3期2卷 139-145页

作者： Zhen Luo Vincent Gasasira Yuhui huang Dengyong Liu Xihong Yang Shihong Jiang wenfeng hu College of Food Science South China Agricultural UniversityGuangzhou 510642PR China National Center of Meat Quality and Safety Control College of Food Science and TechnologyNanjing Agricultural UniversityNanjing 210095PR China College of Food Science&Technology Guangdong Ocean UniversityZhanjiang 524088PR China Guangdong Wen’s Caren Food Co. Ltd.Xinxing County 527400PR China

The aim of this research is to investigate the effect of lactic acid bacteria(LAB)on color stability of fresh *** the seven LAB strains isolated from the Chinese dry-cured hams,H strain was identified as Lactobacillus salivarius(CCTCC M2010374)by serial biochemical tests and 16S rRNA *** fresh pork samples were immersed in the H strain and Lactobacillus fermentum extracts for 1 min after ultrasonic cells disruption and samples immersed in sterile 0.9%(m/V)saline was served as a control group,then samples were vacuum packaged and stored at 4◦*** oxide synthase(NOS)and metmyoglobin(MetMb)reductase were found in the cells extracts of H *** 6 days of storage,H strain group was found to be associated with the highest CIE a*values(Phus shown a beneficial effect on the color stability of fresh *** research is necessary to elucidate its mechanism.©2013 Beijing Academy of Food *** and hosting by Elsevier *** rights reserved.

关键词： Pork Color stability Lactobacillus salivarius Metmyoglobin

Ba_3La_2Ti_2Ta_2O_(15):A New Microwave Dielectricof A_5B_4O_(15)-type Cation-deficient Perovskites

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Journal of Wuhan University of Technology(Materials Science) 2008年第3期23卷 422-424页

作者：胡长征 Key Laboratory of New Processing Technology for Nonferrous Metals and Materials Ministry of EducationGuilin University of Technology

The synthesis, structure and properties of a new A5B4O15-type cation-deficient perovskite Ba3La2Ti2Ta2O15 were discribed. The compound was prepared by the conventional solid-state reaction route. The phase and structure of the ceramics were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）. The results reveal that the compound is successfully synthesized. The compound crystallizes in the trigonal system with unit cell parameter a=5.6730（2） A, c=11.6511（2） A, V=324.93（1） A^3 and Z=1. The microwave dielectric properties of the ceramic are studied using a network analyzer, and it shows a high dielectric constant of 45.1, a high quality factors with Q×fof21 029 GHz, and a positive τf of 5.3 ppm℃^-1.

关键词： X-ray diffraction dielectric resonators microwave ceramics hexagonal perovskites

A Distributed Rescheduling Approach to Railway Network with Fine Granularity in case of Emergencies

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A Distributed Rescheduling Approach to Railway Network with ...