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Acta Geochimica 2018年第4期37卷 632-638页

作者： Khan M.G.Mostofa longlong li Congqiang liu Institute of Surface-Earth System Science Tianjin University State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of Sciences

This study examined the dissolved organic matter(DOM) components of cow dung using a combination of fluorescence(excitation–emission matrix,EEM)spectroscopy and parallel factor(PARAFAC) modelling along with eleven trace metals using ICP-MS and nutrients(NH_4^+ and NO_3^-) using an AA3 auto analyser. EEM–PARAFAC analysis demonstrated that cow dung predominantly contained only one fluorescent DOM component with two fluorescence peaks(Ex/Em=275/311 nm and Ex/Em=220/311 nm),which could be denoted as tyrosine by comparison with its standard. Occurrence of tyrosine can be further confirmed by the FTIR spectra. Trace metals analysis revealed that Na,K and Mg were significantly higher than Ca,Fe,Mn,Zn Sr,Cu,Ni and Co. The NH_4^+ concentrations were substantially higher than NO_3^-.These results thus indicate that the dissolved components of the cow dung could be useful for better understanding its future uses in various important purposes.

关键词： Cow dung Excitation-emission matrix (EEM)spectroscopy Parallel factor (PARAFAC) modelling Tyrosine Trace metals

Highly sensitive color fine-tuning of diblock copolymeric nano-aggregates with tri-metallic cations,Eu(Ⅲ),Tb(Ⅲ),and Zn(Ⅱ),for flexible photoluminescence films(FPFs)

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Journal of Materials Science & Technology 2021年第6期65卷 72-81页

作者： Xinzhi Wang Yao Wang Xinbo Zhang Wei Ding longlong li linjun Huang Laurence A.Belfiore Jianguo Tang Institute of Hybrid Materials National Center of International Joint Research for Hybrid Materials TechnologyNational Base of International Sci.&Tech.Cooperation on Hybrid MaterialsQingdao UniversityQingdao 266071China Department of Chemical and Biological Engineering Colorado State UniversityColorado 80523USA

Luminescence materials have shown promise as display apparatus and lighting *** particularly interesting systems are photoluminescence materials that are capable of reversible colors emitting repeatedly on exposure to *** we report a series of color tunable flexible and transparent photoluminescence films consisting of multi-metals(Eu^(3+),Tb^(3+)and Zn^(3+))induced polymer aggregates(MIPAs)which are distributed uniformly in the polyacrylonitrile(PAN)films without *** have a unique spherical structure due to the self-assembly of polystyrene-block-polyacrylic acid(PS-b-PAA)induced by metal ***,when applied in photoluminescence devices,these photoluminescence films exhibit not only red,green,blue colors(RGB)light,but also other tuned various color light covering the whole visible range upon excitation of 345 nm through adjusting the relative ratios of metal *** the most important key point,non-conductive polymers can be used in photoluminescence devices as host medium,which is not realized in electroluminescent ***,the flexible photoluminescence films(FPFs)innovated herein exhibit the great potential to apply for flexible light-color and light-energy transformation devices.

关键词： Photoluminescence Color tunable Flexible films Polymer aggregates

Hydrocarbon Generation Characteristics of Source Rocks from Different Saline Environments in the Dongpu Depression,Bohai Bay Basin,China

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1260-1278页

作者： li Wendu ZHANG Pengyuan JIANG Fujie ZHANG Yunxian HUANG Renda XU Tianwu ZHOU Yongshui li longlong JIANG Wenli State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Beijing 100083China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China Basin and Reservoir Research Center China University of Petroleum(Beijing)Beijing 102249China Zhongyuan Oilfield Branch SINOPECPuyangHenan 457001China Wuxi Research Institute of Petroleum Geology Sinopec Petroleum Exploration&Production Research InstituteWuxiJiangsu 214000China Strategy Research Center of Oil and Gas Resources Ministry of Land and ResourcesBeijing 100034China

The Dongpu Depression is a secondary salt-bearing tectonic unit in the Bohai Bay Basin,eastern *** depositional environment of this depression regarding its Paleogene strata is clearly different in plane,including the saltwater environment(SE)in the north,the freshwater environment(FE)in the south and the brackish water environment(BE)in the *** result of oil and gas exploration in the Dongpu Depression shows that more than 90%of the proven oil reserves are distributed in the northern saltwater *** studies indicate that the organic geochemistry characteristics and the hydrocarbon generation capacity of the source rocks are very clearly diverse under different environments,which results in the significant differences in the proved reserves between the north and the *** order to further explore the differences in the hydrocarbon generation capacity of the source rocks under distinct depositional environments and the mechanism of their occurrence,three samples from different depositional environments(W18-5 for SE,H7-18 for BE,CH9 for FE)were used for confined gold tube pyrolysis *** results show that the CH4 yields of W18-5,H7-18 and CH9 increase with increasing temperature,the maximum yields being 405.62 mg/g TOC,388.56 mg/g TOC and 367.89 mg/g TOC,*** liquid hydrocarbon yields of W18-5,H7-18 and CH9 firstly increase with increasing temperature and then decrease after the critical *** maximum yields of C6-14 are 149.54 mg/g TOC,140.18 mg/g TOC and 116.94 mg/g TOC,the maximum yields of C14+being 852.4 mg/g TOC,652.6 mg/g TOC and 596.41 mg/g TOC,respectively for W18-5,H7-18 and *** summarize,the order of hydrocarbon potential from high to low is W18-5,H7-18 and *** this basis,through analyzing the influencing factors of hydrocarbon differences,this paper reveals that the saltwater environment is characterized by 4 factors:higher salinity,halophilic algae,high paleo-productivity and a strongly

关键词： sapropelite exinite gold-tube pyrolysis experiment hydrocarbon generation evolutionary model Dongpu Depression Bohai Bay Basin

Biodegradation of occluded hydrocarbons and kerogen macromolecules of the Permian Lucaogou shales,Junggar Basin,NW China

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Energy Geoscience 2023年第1期4卷 179-184页

作者： Yan'e Chen longlong li Zhirong Zhang Paul F.Greenwood Yumin liu Wuxi Branch of SINOPEC Petroleum Exploration and Development Research Institute WuxiJiangsu214126China SINOPEC Key Laboratory of Petroleum Accumulation Mechanisms WuxiJiangsu214126China Hubei Key Laboratory of Petroleum Geochemistry and Environment Yangtze UniversityWuhanHubei430100China School of Earth Sciences University of Western AustraliaCrawleyWA6009Australia Western Australia Organic and Isotope Geochemistry Centre School of Earth and Planetary SciencesCurtin UniversityGPO Box U1987PerthWA6845Australia Hubei Key Laboratory of Petroleum Geochemistry and Environment(Yangtze University) Yangtze UniversityWuhan430100China

Three kerogen samples(JJZG-1,JJZG-2 and JJZG-3)isolated from the Permian Lucaogou shales of varying biodegradation levels(BLs≈0,3 and 7,respectively)were subjected to sequential stepwise pyrolysis combined with on-line detection of gas chromatography-mass spectrometry(GC-MS).Occluded fractions(bitumenⅡ)released at low-temperature steps(≥410℃)show consistent biodegradative signatures with that reported for solvent-extracted fractions(bitumenⅠ)of the original shales,e.g.,broad range of abundant n-alkanes,isoprenoids and regular hopanes for the non-biodegraded JJZG-1;trace n-alkanes and abundant hopanes for the moderately biodegraded JJZG-2;and no n-alkanes but still prominent hopanes including the microbially produced 25-nohopanes for the severely biodegraded *** consistency between bitumenⅡand bitumenⅠfractions indicates the biodegradability of the kerogenoccluded bitumenⅡwith limited protection from host kerogen.A minor level of protection was suggested by the trace distribution of n-alkanes in the bitumenⅡof JJZG-2,whereas the bitumenⅠhad no *** kerogen itself was more resistant to biodegradation as reflected by the persistence of high abundances of both n-alkanes and hopanes in the high temperature(≥460℃)products of all three kerogen ***,the relative abundances of these product groups did show some evidence of biodegradation alteration,e.g.,ratios of n-C_(15)alkene/C_(27)hop-17(21)-ene at 510℃pyrolysis decreased by order of magnitude from the non-biodegraded(JJZG-1=27.4)to highly biodegraded(0.3 for JJZG-3)*** reduced biodegradation impact on the kerogen fraction(*** fractions)was also evident by the absence of 25-norhopanes in the high-temperature analysis of the JJZG-3 kerogen.

关键词： Biodegradation Stepwise pyrolysis Occluded hydrocarbon BitumenⅡ Kerogen Source rock Permian Lucaogou shale Junggar Basin

Review of the detasseling techniques for maize(Zea mays L.)hybrid seed production

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 1-11页

作者： Ruirui Zhang Jiaxuan Yang liping Chen Chenchen Ding longlong li linhuan Zhang National Research Center of Intelligent Equipment for Agriculture Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China National Center of International Research on Agricultural Aerial Application Technology Beijing 100097China Research Center of Intelligent Equipment Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China

Maize(Zea mays L.)is a critical staple crop globally,integral to human consumption,food security,and agricultural product *** quality and purity of maize seeds,essential for hybrid seed production,are contingent upon effective *** study investigates the evolution of detasseling technologies and their application in Chinese maize hybrid seed production,with a comparative analysis against the United States.A comprehensive examination of the development and utilization of detasseling technology in Chinese maize hybrid seed production was undertaken,with a specific focus on key *** from the United States were included for comparative *** analysis encompassed various detasseling methods,including manual,semi-mechanized,and cytoplasmic male sterility,as well as more recent innovations such as detasseling machines,and the emerging field of intelligent detasseling driven by unmanned aerial vehicles(UAVs),computer vision,and mechanical *** detasseling methods were predominantly employed by *** the challenges of inflexible and occasionally overlooked,applying detasseling machines is efficient and *** present,China’s detasseling operations in hybrid maize seed production are mainly carried out by manual work,which is labor-intensive and *** order to address this issue,China is dedicated to developing intelligent detasseling *** study emphasizes the critical role of detasseling in hybrid maize seed *** United States has embraced mechanized *** application and development of manual and mechanized detasseling were applied later than those in the United States,but latest intelligent detasseling technologies first appeared in *** detasseling is expected to be the future direction,ensuring the quality and efficiency of hybrid maize seed production,with implications for global food security.

关键词： detasseling technique detasseling machine UAVs intelligent agriculture maize hybrid seed production

Public key based bidirectional shadow image authentication without pixel expansion in image secret sharing

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Frontiers of Information Technology & Electronic Engineering 2023年第1期24卷 88-103页

作者： Xuehu YAN longlong li Jia CHEN Lei SUN National University of Defense Technology Hefei 230037China

Image secret sharing(ISS)is gaining popularity due to the importance of digital images and its wide application to cloud-based distributed storage and multiparty secure *** image authentication generally includes shadow image detection and identification,and plays an important role in ***,traditional dealer-participatory methods,which suffer from significant pixel expansion or storing auxiliary information,authenticate the shadow image mainly during the decoding phase,also known as unidirectional *** authentication of the shadow image in the distributing(encoding)phase is also important for the *** this study,we introduce a public key based bidirectional shadow image authentication method in ISS without pixel expansion for a(k,n)*** the dealer distributes each shadow image to a corresponding participant,the participant can authenticate the received shadow image with his/her private *** the decoding phase,the dealer can authenticate each received shadow image with a secret key;in addition,the dealer can losslessly decode the secret image with any k or more shadow *** proposed method is validated using theoretical analyses,illustrations,and comparisons.

关键词： Image secret sharing Shadow image authentication Public key Pixel expansion Lossless decoding

Design and experiment of variable rate orchard sprayer based on laser scanning sensor

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International Journal of Agricultural and Biological Engineering 2018年第1期11卷 101-108页

作者： longlong li Xiongkui He Jianli Song Yajia liu Aijun Zeng liu Yang Chaohui liu Zhixiong liu Center for Chemicals Application Technology(CCAT) College of ScienceChina Agricultural UniversityBeijing 100193China Wuxi Zhongbo Machinery Manufacturing Co. LtdWuxi 214028China Beijing Hualing Feichi Information Technology CO. LTDBeijing 100094China

During different growth periods,canopy size and density in orchards are variable,which need application conditions(flow rate and air flow)to be adjusted to match the canopy’s *** order to improve orchard sprayer’s automatic operating performance,an automatic variable-rate orchard sprayer(VARS)fixed with 40 electromagnetic valves and 8 brushless fans was developed based on the canopy’s spatial *** solenoid valve and brushless motor can be individually adjusted in real-time through pulse width modulation(PWM)signals emitted by a control system to adjust each nozzle’s spout and fan rotation speed.A high-precision laser scanning sensor(light detecting and ranging,liDAR)was adopted as the detector to measure the canopy volume using the variable rate algorithm *** experiments were conducted in an apple orchard,and conventional air blast sprayer(CABS)and directed air-jet sprayer(DAJS)were tested as a *** showed that on average,46%less spraying solution was applied compared to conventional applications,while penetration rate was similar to *** deposition in the canopy with variable application was higher than that of conventional applications,indicating that electronic sprayers are more efficient than conventional *** was also observed that VARS could significantly reduce off-target *** field experiment showed that the newly developed variable-rate sprayer can greatly reduce pesticide use and protect the environment for the orchard fruit production,and also provide a reference for design and performance optimization for plant protection machinery.

关键词： variable rate orchard sprayer spatial dimension air volume flow rate laser scanning sensor precision agriculture

Mechanistic investigation of gas injection treatment in a continental shale gas condensate reservoir

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Acta Mechanica Sinica 2024年第9期40卷 22-34页

作者： longlong li Xing Qin Chao Zhou Yuewu liu Wei Pang Luting Wang Jiuge Ding Sinopec Key Laboratory of Drilling Completion and Fracturing of Shale Oil and Gas Beijing 100101China Institute of Mechanics Chinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China SINOPEC Research Institute of Petroleum Engineering Co. Ltd.Beijing 102206China

Low thermal evolution degree of gas and connected fracture network are key features in the continental shale gas *** the pressure decreases lower than the dew point pressure,gas condensate diminishes the mobility of subsurface fluid forms in the near well region,which further reduces the productivity and final recovery factor in addition to the low connected fracture *** work is motivated to investigate the application of gas injection,proven to be a feasible technique in conventional/marine-shale gas condensate reservoirs,in continental shale gas condensate *** apply a compositional model to investigate the mechanism of gas injection treatment taking a continental shale gas condensate reservoir in the Fuxing area,Sichuan Basin,China as an *** results demonstrate that for the removal of gas condensate during CO_(2)injection,re-vaporization plays the main mechanism through two processes including pressurization and development of miscibility,while the former is *** the variation trend of the total volume of gas condensate,we divide the whole injection process into four and six stages in the single fracture model and fracture network model,respectively,and reason the trend with respect to phase behavior and flow pattern.A sensitive study on the injected gas type indicates that the sorting of the gas injection performance to remove gas condensate produced gas followed by CH4,and followed by CO_(2).Finally,we investigate the performance of cyclic produced-gas injection and optimize the injection *** work provides technical and theoretical support for the development of continental shale gas reservoirs.

关键词： Gas injection Gas condensate Continental shale reservoir Mechanism Numerical simulation

Method for UAV spraying pattern measurement with PLS model based spectrum analysis

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International Journal of Agricultural and Biological Engineering 2020年第3期13卷 22-28页

作者： Ruirui Zhang Yao Wen longlong li liping Chen Gang Xu Yanbo Huang Qing Tang Tongchuan Yi National Research Center of Intelligent Equipment for Agriculture Beijing Academy of Agricultural And Forestry SciencesBeijing 100097China Beijing Research Center of Intelligent Equipment for Agriculture Beijing Academy of Agricultural And Forestry SciencesBeijing 100097China National Center for International Research on Agricultural Aerial Application Technology Beijing Academy of Agricultural And Forestry SciencesBeijing 100097China Beijing Key laboratory of Intelligent Equipment Technology for Agriculture Beijing Academy of Agricultural And Forestry SciencesBeijing 100097China United States Department of Agriculture Agricultural Research ServiceCrop Production Systems Research UnitStoneville MS 38776USA

Unmanned aerial vehicle(UAV)chemical application is widely used for crop protection,and spraying pattern is one of the most important factors that influence the chemical control efficacy.A method for UAV spraying pattern measurement with partial least squares(PLS)model based spectrum analysis was proposed in this study to measure the UAV spraying pattern more *** method involved the steps of fluorescent tracer solution spray and its droplets collection,the spectrum on paper strip acquiring,spectrum processing and analysis,PLS *** order to verify the applicability of the method and obtain the parameters of the PLS model,UAV spraying experiments were performed in the *** Fluorescent tracer solution was sprayed and its droplets are collected by paper strip,and the original spectrum on paper strip obtained by a spectrometer was processed by the Savitzky-Golay and standard normalized variable(SNV)*** prediction model of coverage rate selected as the droplet deposition parameter to measure the UAV spraying pattern,was established by using PLS *** verify the superiority of the PLS model,a traditional linear regression(LR)model of coverage rate was established *** results demonstrate that the method with PLS model based spectrum analysis can measure the UAV spraying pattern effectively,and PLS model has a better performance of RV2=0.94 and RMSEP=0.9446 than that of the LR model.

关键词： pattern measurement UAV spraying spectrum model coverage rate partial least squares method

Testing method and distribution characteristics of spatial pesticide spraying deposition quality balance for unmanned aerial vehicle

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International Journal of Agricultural and Biological Engineering 2018年第2期11卷 18-26页

作者： Changling Wang Xiongkui He Xiaonan Wang Zhichong Wang Shilin Wang longlong li Jane Bonds Andreas Herbst Zhiguo Wang College of Science China Agricultural UniversityBeijing 100193China Bonds Consulting Group LLC Panama City Florida 32408USA Institute for Application Techniques in Plant Protection Julius Kühn-Institute(JKI)Federal Research Centre for Cultivated PlantsMesseweg 11/12 D-38104 BraunschweigGermany Quanfeng Aviation Plant Protection Technology Co. Ltd.Anyang 455001China

In order to explore the spatial pesticide spraying deposition distribution,the downwash flow field characteristics for unmanned aerial vehicle(UAV)pesticide application with accurate flight height and velocity and the relationship of these two aspects,a novel measurement method was proposed in this paper.A model‘3WQF80-10’single-rotor diesel UAV was tested using this method in wheat field and the effects of flight direction,flight parameters and crosswind on the distribution of spatial spraying deposition quality balance(SSDQB)and the downwash flow field distribution were researched.A cuboid aluminum sampling frame of spatial spraying deposition quality balance(SFSSDQB)with monofilament wires was made for collecting the droplets in four directions,and a set of multi-channel micro-meteorology measurement system(MMMS)was applied for measuring the downwash wind speed in three ***,BeiDou Navigation Satellite System(BNSS)was used for controlling and recording the working height,velocity and track of this model of single-rotor *** results showed the distribution of the spatial spray deposition and the downwash flow field of UAV could be measured effectively at exact flight height and velocity via this *** the average wind speed was 0.9 m/s,the average temperature was 31.5℃ and the average relative humidity was 34.1%,and the average distribution ratios of spraying deposition for model‘3WQF80-10’UAV on the upwind part,the top part,the downwind part and the bottom part were 4.4%,2.3%,50.4%and 43.7%,*** flight directions of forward and backward had an impact on droplet deposition distribution and the working effect of flying backwards,with 60%of deposition ratio of the bottom part of the SFSSDQB,was better than flying *** was a linear negative correlation between the coefficient of variation(CV)of the bottom part and the flight height and the coefficient of determination was 0.9178,which means that the deposition distribution

关键词： unmanned aerial vehicle(UAV) spatial spraying deposition distribution downwind airflow flow field