维普中文期刊产品整合服务
539篇 您的检索式:作者名="Xueming"
    题名 作者 年代 出处 被引量
1Phosphorus fractions and its release in the sediments of Haihe River,China显示文摘The amounts and forms of phosphorus(P) in surface sediments of Haihe River,Tianjin,North China,were examined using a sequential chemical extraction procedure.Five fractions of sedimentary P,including loosely sorbed P(NH4Cl-P),redox-sensitive P(BD-P),metal oxide bound P(NaOH-P),calcium bound P(HCl-P),and residual P(Res-P)(organic and refractory P),were separately quantified.The results indicated that the contents of different P fractions in the sediments varied greatly.The total P(TP) contents ranged from 968 to 2017 mg/kg.Phosphorus contents in NH4Cl-P,BD-P,NaOH-P,and HCl-P ranged from 6.7 to 26.6 mg/kg,54.5 to 90.2 mg/kg,185.2 to 382.5 mg/kg,and 252.3 to 425.5 mg/kg,respectively,which represented 1.2%-3.2%,7.7%-13%,33.3%-48.9%,and 36.2%-54.2% of the sedimentary inorganic P,respectively.For all the sediment samples,the rank order of P-fractions was Res-P > HCl-P > NaOH-P > BD-P > NH4Cl-P.The highly positive relationship between the amounts of P released from the sediments and those in the NH4Cl-P and BD-P fractions,indicated that NH4Cl-P and BD-P were the main fractions that can release P easily.SUN Shujuan HUANG Suiliang SUN Xueming WEN Wei 2009Journal of Environmental Sciences2009,21,3:53
2Spinal Cord Stimulation for Pain Treatment After Spinal Cord Injury显示文摘In addition to restoration of bladder, bowel, and motor functions, alleviating the accompanying debilitating pain is equally important for improving the quality of life of patients with spinal cord injury(SCI). Currently,however, the treatment of chronic pain after SCI remains a largely unmet need. Electrical spinal cord stimulation(SCS) has been used to manage a variety of chronic pain conditions that are refractory to pharmacotherapy. Yet, its efficacy, benefit profiles, and mechanisms of action in SCI pain remain elusive, due to limited research, methodological weaknesses in previous clinical studies, and a lack of mechanistic exploration of SCS for SCI pain control. We aim to review recent studies and outline the therapeutic potential of different SCS paradigms for traumatic SCI pain. We begin with an overview of its manifestations,classification, potential underlying etiology, and currentchallenges for its treatment. The clinical evidence for using SCS in SCI pain is then reviewed. Finally, future perspectives of pre-clinical research and clinical study of SCS for SCI pain treatment are discussed.Qian Huang Wanru Duan Eellan Sivanesan Shuguang Liu Fei Yang Zhiyong Chen Neil C.Ford Xueming Chen Yun Guan 2019Neuroscience Bulletin2019,35,3:13
3EXTRACTION AND SEPARATION OF RADISH RED PIGMENT FROM A WASTE WATER OF SALTING RADISH BY D61 RESIN显示文摘EXTRACTIONANDSEPARATIONOFRADISHREDPIGMENTFROMAWASTEWATEROFSALTINGRADISHBYD61RESINZhouXiaohua;KangJane;ShanXueming(Resorses'Co...Zhou Xiaohua Kang Jane Shan Xueming(Resorses’ Comprehensive Utilization Engineering Centre of Chongqing University, Chongqing) 1996Chinese Journal of Reactive Polymers1996,5,1:13
4Microstructure and electrical properties of Y_2O_3-doped ZnO-based varistor ceramics prepared by high-energy ball milling显示文摘Y2O3-doped ZnO-based varistor ceramics were prepared using high-energy ball milling (HEBM) and low-temperature sin- tering technique, with voltage-gradient of 1934-2197 V/mm, non-linear coefficients of 20.8-21.8, leakage currents of 0.59-1.04 μA, and densities of 5.46-5.57 g/cm3. With increasing Y2O3 content, the voltage-gradient increases because of the decrease of ZnO grain size; the non-linear coefficient and the leakage current improve but the density decreases because of more porosity; the donor con- centration and density of interface states decrease, whereas the barrier height and width increase because of the acceptor effect of Y2O3 in varistor ceramics.Hongyu Liu Xueming Ma Dongmei Jiang Wangzhou Shi 2007Journal of University of Science and Technology Beijing2007,14,3:13
5Genesis of sandstone-type uranium deposits along the northern margin of the Ordos Basin,China显示文摘Sandstone-type U mineral resources are among the important sources for nuclear energy.The U deposits in the Ordos Basin in China form part of the northern segment of the sandstone-hosted Central Asian Uranium MegaProvince.Two types of mineralizations are recognized in this basin:'phreatic permeable type'and'interlayer permeable type',both exhibiting features equivalent to roll-front subtypes.The'interlayer permeable type'is widely accepted as the dominant mineralization type for sandstone-type uranium deposits within large-scale basins,also designated as the'interlayer oxidation zone type',based on the horizontal color zoning model representing changing redox conditions.Here we synthesize data from several drill holes within the Ordos Basin,which suggest that major Mesozoic tectonic movements controlled the evolution of the sedimentary system in the basin.These tectonic movements contributed to the formation of three angular unconformities and four parallel unconformities as inferred from the stratigraphic relationships.In addition,other features such as vertical color zoning,paleo-channel controlled tabular or lentoid ore bodies(without roll-type)and a group interlayer horizontal zoning of altered minerals are also documented.Sequence stratigraphic analysis indicates that the Ordos Basin generally witnessed four cycles of water level variations during Mesozoic.During the variations,three high water level and three low water level events were recorded.Biological characteristics imply that the Ordos Basin went through multiple arid to humid climatic evolutions during Mesozoic.Combining the newly documented features with some novel concepts on the hydrodynamic mechanism for supergene ore-forming fluids,we propose a metallogenic model which invokes the importance of tectonic movements and water level fluctuations to explain the genesis of uranium deposits along the northern margin of the Ordos Basin.Ruoshi Jin Xueming Teng Xiaoguang Li Qinghong Si Wei Wang 2020Geoscience Frontiers2020,11,1:13
6Impact of Accessibility on Housing Prices in Dalian City of China Based on a Geographically Weighted Regression Model显示文摘This paper studies the relationship between accessibility and housing prices in Dalian by using an improved geographically weighted regression model and house prices, traffic, remote sensing images, etc. Multi-source data improves the accuracy of the spatial differentiation that reflects the impact of traffic accessibility on house prices. The results are as follows: first, the average house price is 12 436 yuan(RMB)/m^2, and reveals a declining trend from coastal areas to inland areas. The exception was Guilin Street, which demonstrates a local peak of house prices that decreases from the center of the street to its periphery. Second, the accessibility value is 33 minutes on average, excluding northern and eastern fringe areas, which was over 50 minutes. Third, the significant spatial correlation coefficient between accessibility and house prices is 0.423, and the coefficient increases in the southeastern direction. The strongest impact of accessibility on house prices is in the southeastern coast, and can be seen in the Lehua, Yingke, and Hushan communities, while the weakest impact is in the northwestern fringe, and can be seen in the Yingchengzi, Xixiaomo, and Daheishi community areas.YANG Jun BAO Yajun ZHANG Yuqing LI Xueming GE Quansheng 2018Chinese Geographical Science2018,28,3:10
7Revealing the behavior of soliton buildup in a mode-locked laser显示文摘Real-time spectroscopy based on an emerging time-stretch technique can map the spectral information of optical waves into the time domain,opening several fascinating explorations of nonlinear dynamics in mode-locked lasers.However,the self-starting process of mode-locked lasers is quite sensitive to environmental perturbation,which causes the transient behaviors of lasers to deviate from the true buildup process of solitons.We optimize the laser system to improve its stability,which suppresses the Q-switched lasing induced by environmental perturbation.We,therefore,demonstrate the first observation of the entire buildup process of solitons in a mode-locked laser,revealing two possible pathways to generate the temporal solitons.One pathway includes the dynamics of raised relaxation oscillation,quasimode-locking stage,spectral beating behavior,and finally the stable single-soliton mode-locking.The other pathway contains,however,an extra transient bound-state stage before the final single-pulse modelocking operation.Moreover,we propose a theoretical model to predict the buildup time of solitons,which agrees well with the experimental results.Our findings can bring real-time insights into ultrafast fiber laser design and optimization,as well as promote the application of fiber laser.Xueming Liu Yudong Cui 2019Advanced Photonics2019,1,1:9
8Polymorphisms of three gene-derived STS on pig chromosome 13q41 are associated with susceptibility to enterotoxigenic Escherichia coli F4ab/ac in pigs显示文摘Neonatal diarrhea caused by enterotoxigenic Escherichia coli(ETEC)F4 is a common and serious disease,resulting in significant economical loss in the pig industry.The locus encoding ETEC F4 receptor has been mapped to pig chromosome(SSC)13q41,and one of the most significantly linked markers is S0075.In this study,we selected three genes including SLC12A8,MYLK and KPNA1 from a chromosomal region flanking S0075 on SSC13 to develop pig specific sequence tagged sites(STS). Seven single nucleotide polymorphisms were identified in the three pig STS using DNA of four full-sib susceptible and resistant animals in a White Duroc×Erhualian intercross.All grandparents,parents and 755 offspring in the intercross were genotyped for three polymorphisms,including SLC12A8 g.159A>G,MYLK g.1673A>G and KPNA1 g.306A>G.Family-based transmission disequilibrium test(TDT) revealed that all polymorphisms and the corresponding haplotypes are significantly associated with ETEC F4ab/ac(especially F4ac)brush border adhesion phenotypes,indicating that these polymor- phism are in linkage disequlibrium with causal mutation(s)of the gene encoding ETEC F4ab/ac receptor. Our results strengthen the evidence for the involvement of SSC13q41 in high acquiring risk of ETEC F4ab/ac infection,and provide novel polymorphic markers for fine mapping of the ETEC F4ab/ac receptor locus.HUANG Xiang 1 ,REN Jun 1 ,YAN XueMing 1,2 ,PENG QiuLing 1 ,TANG Huan 1 ,ZHANG Bo 1 ,JI HuaYuan 1 , YANG ShuJin1&HUANG LuSheng 1 1Key Laboratory for Animal Biotechnology of Jiangxi Province and the Ministry of Agriculture of China,Jiangxi Agricultural University, Nanchang 330045,China 2Department of Biology,Nanchang University of Science and Technology,Nanchang 330038,China 2008Science China(Life Sciences)2008,51,7:8
9Nutrient distribution within and release from the contaminated sediment of Haihe River显示文摘We assessed nutrient characteristics, distributions and fractions within the disturbed and undisturbed sediments at four sampling sites within the mainstream of Haihe River. The river sediments contained mostly sand (> 60%). The fraction of clay was < 3%. Total nitrogen (TN) and total phosphorus (TP) concentrations ranged from 729 to 1922 mg/kg and from 692 to 1388 mg/kg, respectively. Nutrient concentrations within the sediments usually decreased with increasing depth. The TN and TP concentrations within the fine sand were higher than for that within silt. Sediment phosphorus fractions were between 2.99% and 3.37% Ex-P (exchangeable phosphorus), 7.89% and 13.71% Fe/Al-P (Fe, Al oxides bound phosphorus), 61.32% and 70.14% Ca-P (calcium-bound phosphorus), and 17.03% and 22.04% Org-P (organic phosphorus). Nitrogen and phosphorus release from sediment could lead to the presence of 21.02 mg N/L and 3.10 mg P/L within the water column. A river restoration project should address the sediment nutrient stock.Min Wu Suiliang Huang Wei Wen Xueming Sun Xianqiang Tang Miklas Scholz 2011Journal of Environmental Sciences2011,23,7:7
10A Geochemical Study of an REE-rich Carbonatite Dyke at Bayan Obo,Inner Mongolia,Northern China显示文摘An REE-rich carbonatite dyke was found in Dulahala, close to the Bayan Obo superlarge REE-Nb-Fe mineral deposit in Inner Mongolia, northern China. The REE content in the dyke varies greatly, from 1% up to 20% (wt), which might constitute rich REE ores. Light REEs in the carbonatite are enriched and highly fractionated relative to heavy REEs and there is no Eu anomaly. The REE and trace element distribution patterns of the carbonatite are identical to those of fine-grained dolomite marble which is the host rock of the Bayan Obo REE-Nb-Fe superlarge mineral deposit. This indicates a petrogenetic linkage between the REE-rich carbonatite and the mineralizations in this region.YANG Xueming ZHENG Yongfei YANG Xiaoyong ZHANG Peishan M.J.LE BAS 2000Acta Geologica Sinica(English Edition)2000,74,3:7
11Assimilating operational SST and sea ice analysis data into an operational circulation model for the coastal seas of China显示文摘The prediction of sea surface temperature(SST) is an essential task for an operational ocean circulation model. A sea surface heat flux, an initial temperature field, and boundary conditions directly affect the accuracy of a SST simulation. Here two quick and convenient data assimilation methods are employed to improve the SST simulation in the domain of the Bohai Sea, the Yellow Sea and the East China Sea(BYECS). One is based on a surface net heat flux correction, named as Qcorrection(QC), which nudges the flux correction to the model equation; the other is ensemble optimal interpolation(En OI), which optimizes the model initial field. Based on such two methods, the SST data obtained from the operational SST and sea ice analysis(OSTIA) system are assimilated into an operational circulation model for the coastal seas of China. The results of the simulated SST based on four experiments, in 2011, have been analyzed. By comparing with the OSTIA SST, the domain averaged root mean square error(RMSE) of the four experiments is 1.74, 1.16, 1.30 and 0.91°C, respectively; the improvements of assimilation experiments Exps 2, 3 and 4 are about 33.3%, 25.3%, and 47.7%, respectively.Although both two methods are effective in assimilating the SST, the En OI shows more advantages than the QC,and the best result is achieved when the two methods are combined. Comparing with the observational data from coastal buoy stations, show that assimilating the high-resolution satellite SST products can effectively improve the SST prediction skill in coastal regions.JI Qiyan ZHU Xueming WANG Hui LIU Guimei GAO Shan JI Xuanliang XU Qing 2015Acta Oceanologica Sinica2015,34,7:7
12Solitons in the fractional Schr?dinger equation with parity-time-symmetric lattice potential显示文摘We investigate the properties of spatial solitons in the fractional Schr?dinger equation(FSE) with parity-time(PT)-symmetric lattice potential supported by the focusing of Kerr nonlinearity. Both one-and two-dimensional solitons can stably propagate in PT-symmetric lattices under noise perturbations. The domains of stability for both one-and two-dimensional solitons strongly depend on the gain/loss strength of the lattice. In the spatial domain, the solitons are rigidly modulated by the lattice potential for the weak diffraction in FSE systems. In the inverse space, due to the periodicity of lattices, the spectra of solitons experience sharp peaks when the values of wavenumbers are even. The transverse power flows induced by the imaginary part of the lattice are also investigated, which can preserve the internal energy balances within the solitons.XIANKUN YAO XUEMING LIu 2018Photonics Research2018,6,9:6
13Metallogenic geochemistry of Sb-mineralization in southern margin of North China platform显示文摘1 Geological setting THE Sb mineralization zone in the south margin of North China platform is located in the transitional edgeof North China plate and Yangtze plate, belonging to Qinling fold system, whose tectonic line is inNWW-SEE direction regionally. Because of the huge compression caused by the collision of the twoplates, the rocks undergone strong deformation and metamorphism have very complicated structures. Theregional deep fault-Shuanghuaishu fault-controls Sb-mineralization zone belt, and all the Sb-oredeposits or mineralized spots appear alone at the very southern margin of the fault. The lithostragraphirunits in the mineralized zone are relatively simple, mainly composed of Jiebei Group (Pt2J2) of QinglingFormation (with middle-high metamorphsim) and the upper Triassic system (with little metamorphism).YANG Xiaoyong~1, YANG Xueming~1, ZHANG Jianjun~2, CAO Gaoshe~2 and ZHANG Zhengwei~2 1. Department of Earth and Space Sciences, University of Science and Technlogy of China, Hefei 230026, China 2. Institute of Geology, Henan Bureau of Geology and Mineral Resources, Zhengzhou 450053, China 1999Chinese Science Bulletin1999,44,S2:6
14Source apportionment of VOCs in a typical medium-sized city in North China Plain and implications on control policy显示文摘Characteristics of atmospheric VOCs(volatile organic compounds) have been extensively studied in megacities in China, however, they are scarcely investigated in medium/smallsized cities in North China Plain(NCP).A comprehensive research on possible sources of VOCs was conducted in a medium-sized city of NCP, from May to September 2019.A total of 143 canister samples of 8 sites in Xuchang city were collected, and 57 VOC species were detected.The average VOC concentrations were 42.6 ± 31.6 μg/m3, with 53.7 ± 31.0 μg/m3 and 32.1 ± 27.8 μg/m^(3), in the morning and afternoon, respectively.Alkenes and aromatics contributed 80% of the total ozone formation potential(OFP).Aromatics accounted for more than 95% of secondary organic aerosol potential(SOAP).VOCs were dominated by the local emission with significant transport from the southeast direction.PMF analysis extracted 6 sources, which were combustion(33.1%), LPG usage(19.3%), vehicular exhaust & fuel evaporation(15.8%), solvent usage(15.2%), industrial(9.11%) and biogenic(7.51%), respectively and they contributed 33.4%, 17.6%, 12.9%, 18.6%, 9.28% and 8.22% to the OFP, respectively.Combustion and LPG usage were the dominant VOC sources;and combustion, solvent usage and LPG usage were the main sources of OFP in Xuchang city, which were different to megacities in China with a high contribution from vehicular exhaust, solvent usage and industry,suggesting specific control strategies on VOCs need to be implemented in medium-sized city such as Xuchang city.Juanjuan Qin Xiaobo Wang Yanrong Yang Yuanyuan Qin Shaoxuan Shi Peihua Xu Rongzhi Chen Xueming Zhou Jihua Tan Xinming Wang 2021Journal of Environmental Sciences2021,33,9:6
15Late Paleozoic Fluid Systems and Their Ore-forming Effects in the Yuebei Basin,Northern Guangdong,China显示文摘Based on detailed and systematic researches of the geology of ore deposits, fluid inclusions and isotope geochemistry etc., and regarding the Late Paleozoic fluid system of the Yuebei Basin as an integrated object in this paper, we have revealed the temporo-spatial evolution law of the basin’s fluid system and discussed its ore-forming effects by simulating and analyzing the distribution of ore-forming elements, the fluid thermodynamics and dynamics of evolution processes of this basin. The results show that Late Paleozoic ore-forming fluid systems of the Yuebei Basin include four basic types as follows. (1) The sea floor volcanic-exhalation system developed during the rapid basin slip-extension stage in the Mid-Late Devonian, which affected the Dabaoshan region. It thus formed the Dabaoshan-type Cu-Pb-Zn-Fe sea floor volcanic-exhalation sedimentary deposits. (2) The compaction fluid system developed during the stable spreading and thermal subsidence-compression stage of the basin in the Mid-Late Devonian. The range of its effects extended all over the whole basin. It resulted in filling-metasomatic deposits, such as the Hongyan-type pyrite deposits and pyrite sheet within the Fankou-type Cu-Pb-Zn-S deposits. (3) The hot water circulation system of sea floor developed during the stage of basin uplifting and micro-aulacogen from the late Late Carboniferous to Middle Carboniferous. The range of its effects covered the Fankou region. It thus formed MVT deposits, such as the main orebody of the Fankou-type Pb-Zn-S deposits. (4) The gravity fluid system developed during the stage of fold uplifting and the basin closed from Middle Triassic to Jurassic, forming groundwater hydrothermal deposits, e.g. the veinlet Pb-Zn-calcite orebodies of the Fankou-type Pb-Zn-S deposits. Migration and concentration of the ore-forming fluids were constrained by the state of temporo-spatial distribution of its fluid potential. Growth faults not only converged the fluids and drove them to move upwards, but also the fluids often crossed the faults to the edges of the basin at the bottom of these faults and the lithologic interfaces, and even migrated to the basin’s edges from top to bottom along the faults, which may be one of the basic reasons for the stratabound deposits to cluster mainly along the contemporaneous faults on the inner border of the basin. The superposed mineralization resulting from the multi-stage activity of contemporaneous faults and ore-forming fluid systems in the basin may be one of the key factors for forming superlarge ore deposits.DENG Jun YANG Liqiang SUN Zhongshi WANG Jianping WANG Qingfei CHENG Xueming ZHOU Yinghua 2005Acta Geologica Sinica(English Edition)2005,79,5:6
16Numerical study and prediction of nuclear contaminant transport from Fukushima Daiichi nuclear power plant in the North Pacific Ocean显示文摘On March 11,2011,a large earthquake and subsequent tsunami near the east coast of Japan destroyed the Fukushima Daiichi nuclear power plant(FD-NPP),causing a massive release of nuclear contaminants.In this paper,a Pacific basin-wide physical dispersion model is developed and used to investigate the transport of nuclear contaminants.The Pacific circulation model,based on the Regional Ocean Modeling System(ROMS),is forced with air-sea flux climatology derived from COADS(the Comprehensive Ocean-Atmosphere Data Set).It is shown that ocean current dominates nuclear contaminant transport.Following the Kuroshio Extension and North Pacific Current,nuclear contaminants at the surface will move eastward in the Pacific as far as 140°W,thereafter dividing into two branches.For the south branch,nuclear contaminants will be transported westward by the equatorial current,and can reach the Philippines after 10 years' time.In contrast,the north branch will arrive at the American west coast and then migrate to the Bering Sea.At 200 m water depth,part of the nuclear materials will move southwestward along with deep ocean circulation,which could potentially reach the east coast of Taiwan.The other part will move to the west coast of America and separate into two branches.One will move northward along the west coast of Alaska,while the other will travel southward to the Hawaiian Islands.The transport of radiation contaminants below 500 m is slow,and will primarily remain in the central Pacific.The physical dispersion model results show that high concentrations of the radioactive isotope cesium-137(137 Cs) will move eastward and reach the central Pacific and west coast of North America in two and eight years,respectively.The sea areas influenced by the nuclear contaminants continue to expand,while peak concentrations decrease in the North Pacific.WANG Hui WANG ZhaoYi ZHU XueMing WANG DaKui LIU GuiMei 2012Chinese Science Bulletin2012,57,26:6
17Effects of Tillage Management on Infiltration and Preferential Flow in a Black Soil, Northeast China显示文摘The impacts of no-tillage (NT) and moldboard plough (MP) managements on infiltration rate and preferential flow were characterized using a combined technique of double-ring device and dye tracer on a black soil (Mollisols) in Northeast China. The objective of this study is to evaluate how tillage practices enhance soil water infiltration and preferential flow in favor of soil erosion control in the study area. The steady infiltration rates under NT management are 1.6 and 2.1 times as high as those under MP management in the 6th and 8th years of the tillage management in place, while the infiltrated water amounts under NT management are 1.4 and 2.0 times as high as those under MP management, respectively. The depth of methylene blue penetrated into NT soil increases from 43cm in the 6th year to 57cm in the 8th year, which are 16cm and 19cm deeper than those in MP soil, respectively. The results of morphologic image show that more biological macro-pores occur in NT soil than in MP soil. These macro-pores play a key role in enhancing preferential flow in NT soil, which in turn promotes water infiltration through preferential pathways in NT soil. The results are helpful to policy-making in popularizing NT and have the implications for tillage management in regard to soil erosion control in black soil region of China.FAN Ruqin ZHANG Xiaoping YANG Xueming LIANG Aizhen JIA Shuxia CHEN Xuewen 2013Chinese Geographical Science2013,23,3:6
18Amyloid fibril structure of α-synuclein determined by cryo- electron microscopy显示文摘Yaowang Li Chunyu Zhao Feng LUO Zhenying Liu Xinrui Gui Zhipu LUO Xiang Zhang Dan Li Cong Liu Xueming Li 2018Cell Research2018,28,9:5
19Nb_2O_5-carbon core-shell nanocomposite as anode material for lithium ion battery显示文摘Mb2O5 -carbon nanocomposite is synthesized through a facile one-step hydrothermal reaction from sucrose as the carbon source,and studied as an anode material for high-performance lithium ion battery.The structural characterizations reveal that the nanocomposite possesses a core-shell structure with a thin layer of carbon shell homogeneously coated on the Nb2O5 nanocrystals.Such a unique structure enables the composite electrode with a long cycle life by preventing the Nb2O5 from volume change and pulverization during the charge-discharge process. In addition,the carbon shell efficiently improves the rate capability.Even at a current density of 500 mA·g-1,the composite electrode still exhibits a specific capacity of~100 mAh·g-1.These results suggest the possibility to utilize the Nb2O5-carbon core-shell composite as a high performance anode material in the practical application of lithium ion battery.Ge Li Xiaolei Wang Xueming Ma 2013Journal of Energy Chemistry2013,22,3:5
20Development and validation of an analytical method for detecting chlorantraniliprole residues in fresh tea leaves显示文摘An efficient method using multiwalled carbon nanotubes(MWCNTs)as dispersive solid-phase extraction sorbent was established for determining chlorantraniliprole residues in fresh tea leaves,which are known to be a troublesome matrix containing abundant pigments,via gas chromatography with an electron capture detector.Acetonitrile was used as the extraction solvent,with sodium chloride enhancing the analyte partition in the organic phase.The optimal mixture of MWCNTs and primary secondary amine(PSA)was based on the distribution of the target analyte recovery and on the clean-up efficiency;while matrix-matched calibration was recommended to combat the matrix effect.Mean recoveries of 95.2%–108.8%were obtained with intraday and interday precisions of less than 7.9%and 10.3%,respectively.Good linearity was observed for concentrations of 0.02–1.0 mg/kg with a correlation coefficient of 0.9984.The limits of detection and quantification were 0.005 mg/kg and 0.02 mg/kg,respectively.The method was employed to investigate the dissipation dynamics of chlorantraniliprole in fresh tea leaves with real field samples.Consequently,the dissipation rates of chlorantraniliprole in fresh tea leaves followed pseudo-first-order kinetics with a half-life of 1.9 d,and the average chlorantraniliprole residue content was below 0.02 mg/kg with a harvest withholding period of 14 d.Tengfei Liu Minghui Dong Fengjie Zhou Daifeng Yang Xueming Zhang 2019Food Science and Human Wellness2019,8,4:5
返回顶部 每页显示:
共27页 首页 上一页 第1页 下一页 末页 /27 跳转

网站首页 | 关于我们 | 联系我们 | 产品服务 | 客服中心 | 广告服务 | 版权声明 | 网站联盟 | 友情链接 | 售卡网点

版权所有© 渝B2-20050021-1 渝公网安备 50019002500403号 违法和不良信息举报中心

互联网出版许可证 新出网证(渝)字10号 全国400电话 - 免长途话费