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谷物及其制品中11种真菌毒素污染水平的测定与分析

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化学研究与应用 2025年第1期37卷 33-39页

作者：侯广月徐志娇周莉莉李大为卞英芳姚傲男山东省产品质量检验研究院山东济南250102 国家加工食品质量检验检测中心(山东) 山东济南250102

建立了超高效液相色谱-串联质谱技术同时检测谷物及其制品中11种真菌毒素的方法。样品经84%乙腈水溶液振荡提取,离心、氮吹,复溶,选择0.1%甲酸水-甲醇为流动相梯度洗脱目标化合物,以反相色谱柱进行分离,采用电喷雾离子源正离子模式和多... 详细信息

建立了超高效液相色谱-串联质谱技术同时检测谷物及其制品中11种真菌毒素的方法。样品经84%乙腈水溶液振荡提取,离心、氮吹,复溶,选择0.1%甲酸水-甲醇为流动相梯度洗脱目标化合物,以反相色谱柱进行分离,采用电喷雾离子源正离子模式和多反应监测模式进行质谱分析。结果表明,11种真菌毒素在一定浓度范围内线性关系良好,方法检出限为0.1~2.0μg·kg^(-1),定量限为0.4~6.0μg·kg^(-1)。在三个添加水平下,平均回收率为94.5%~111.7%,相对标准偏差为0.85%~8.98%。应用本方法对小麦、玉米、大米、小麦粉等790批次典型谷物及其制品中11种真菌毒素污染水平进行研究,其中182批次谷物样品中检出真菌毒素,检出率为29%,具有一定的地域性和季节性;小麦粉有1批次样品检出玉米赤霉烯酮,检出率低于小麦样品的。

关键词：谷物及其制品真菌毒素超高效液相色谱-串联质谱法污染调查分析

A FINITE VOLUME SEMI-IMPliCIT SEMI-LAGRANGIAN SCHEME ON THE YIN-YANG MESH

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Journal of Tropical Meteorology 2019年第3期25卷 373-384页

作者： liU Yu-di li da-wei Institute of Meteorology and Oceanography National University of Defense Technology

Designed for grid point systems, the traditional semi-Lagrangian semi-implicit scheme is not mass-conserving and can lead to significant solution errors. In the present study, a finite-volume semi-Lagrangian semi-implicit scheme(hereafter 'FVSLSI') is designed for the Yin-Yang mesh and tested in a barotropic shallow water model in the spherical coordinate system. Three test cases, i.e. the advection of a solid body, a steady state nonlinear zonal geostrophic flow and the deformation flow, are simulated to compare the performance of the FVSLSI with that of the traditional semi-Lagrangian scheme(hereafter 'SL') from perspectives of shape preservation, mass conservation,normalized bias, and convergence rate. Results indicate that the FVSLSI performs better than the SL in mass conservation and shape preservation. The bias by the FVSLSI is smaller than that by the SL, while the rate of convergence by the FVSLSI is larger than that by the SL. The FVSLSI also allows large time step. Therefore, the FVSLSI is suggested to be distributed to communities that are developing atmospheric/oceanic models.

关键词： semi-implicit scheme semi-Lagrangian scheme mass-conservative scheme Yin-Yang mesh finite volume

Effects of Hypoxia on the Growth and Development of the Fetal Ovine Hepatocytes in Primary Culture

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Biomedical and Environmental Sciences 2019年第8期32卷 592-601页

作者： CAO li WANG Juan BO Le li da wei YIN Na ZHOU An Wen MAO Cai Ping Reproductive Medicine Center First Affiliated Hospital of Soochow UniversitySuzhou 215006JiangsuChina College of Pharmaceutical Sciences Soochow UniversitySuzhou 215006JiangsuChina

Objective To investigate the development and characterizations of the hepatocytes isolated from fetal ovine and to determine the effect of hypoxia on their growth and *** Fresh hepatocytes were isolated from the liver of fetal ovine at late gestation, cultured in specific media, and exposed to normoxia(21% O2) or hypoxia(2% O2).The cellular characteristics and population purity were identified by immunocytochemistry and flow cytometry(FCM).The effects of hypoxia on cell cycle and apoptosis of the hepatocytes were evaluated by FCM, whereas the cellular ultrastructure changes were examined with a transmission electron *** The cell purity of hepatocytes was over 95%.Under hypoxia exposure, the hepatocytes showed a gradual increase in proportion at the S phase and in proliferative index, followed with a compatible increase in apoptosis and progressively decreased cell ***, the organelles of the hepatocytes demonstrated dramatic changes, including swelling of mitochondria, disorder in cristae arrangement, expansion of endoplasmic reticulum, and a large number of circular lipid droplets emerging in the *** Fetal ovine hepatocytes could be primarily cultured in a short-term culture system with a high purity of over 95% and with their preserved original *** could induce changes in ultrastructural and inhibit the proliferation of cultured fetal ovine hepatocytes through apoptotic mechanisms.

关键词： Cell cycle Fetal ovine hepatocytes Hepatocytes structure Hypoxia Primary culture

Late Pleistocene-Holocene slip history of the Langshan-Seertengshan piedmont fault(Inner Mongolia,northern China) from cosmogenic ^(10)Be dating on a bedrock fault scarp

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Journal of Mountain Science 2016年第5期13卷 882-890页

作者： SHEN Xiao-ming li De-wen TIAN Yun-tao LV Yan-wu li da-wei li Yan-feng Key Laboratory of Crustal Dynamics Institute of Crustal DynamicsCEA Department of Earth Sciences University College London National Earthquake Response Support Service CEA

Offset geomorphic features and deformed late Quaternary strata indicate active deformation along the Langshan-Seertengshan piedmont fault （LSPF）, one of the most active faults in the Hetao fault zone in Inner Mongolia, North China. The widespread occurrence of bedrock fault scarps along the LSPF offers excellent opportunity to examine the faulting history. Using cosmogenic ^10Be exposure dating, we measured the exposure ages of the western Langshankou scarp, located in the middle segment of the LSPF. Our data revealed at least two earthquakes that occurred at 22.2±3.3 Ira and 7.2±2.4 ka, respectively. These events are consistent with previous paleoseismic trench studies. The regression of the relationship between the age and sampling height along the scarp yield a fault slip rate of 0.10 ±0.05/-0.06 mm/yr, which is significantly lower than the average post-late Pleistocene fault slip rate of ~1 mm/yr, as estimated from the offset of the T2 terraces by previous studies. This indicates that the slip of the LSPF may have been accommodated by other fault branches.

关键词： Lanshan-Seertengshan piedmont fault(LSPF) Fault scarp Cosmogenic nuclide Exposureage Fault slip rate

Wavelength Dependence of Laser-Induced Bulk damage Morphology in KDP Crystal:Determination of the damage Formation Mechanism

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Chinese Physics Letters 2012年第3期29卷 216-219页

作者： HU Guo-Hang ZHAO Yuan-An li da-wei XIAO Qi-ling Key Laboratory of Materials for High Power Laser Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800

Wet etch process is applied to expose the bulk damage sites in KDP crystals to the surface for the examination by scanning electron microscopy(SEM)and optical *** damage sites induced by 1064 nm laser consist of three distinct regions:a core,an outer region of modified material,and some oriented *** irradiated with 355 nm results in an increase of damage density,a decrease of core diameter and,rarely,occurrence of the *** Laboratory of Materials for High Power Laser,Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences,Shanghai 201800th dependence of the damage feature suggests that a repulsive force exists among the adjacent plasmas,which prevents further expansion of plasma and decreases the size of *** deposited energy absorbed by the smaller plasma may not be able to generate the crack.

关键词： Crystal damage KDP

Runoff projections of the Qinling Mountains and their impact on water demand of Guanzhong region in Northwest China

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Journal of Mountain Science 2022年第8期19卷 2272-2285页

作者： ZHANG Zhao-peng DUAN Ke-qin liU Huan-cai MENG Ya-li CHEN Rong li da-wei li Shuang-shuang School of Geographical Sciences and Tourism Shaanxi Normal UniversityXi'an 710062China School of Geographical Sciences Shanxi Normal UniversityLinfen 041081China

The Qinling Mountains are the main source of water supply to the weihe River and Hanjiang River,but systematic studies on runoff changes in this region are *** study simulated the annual runoff in the Qinling Mountains from 1970 to 2015 using the Variable Infiltration Capacity(VIC)hydrological model and projected runoff changes from 2015 to 2100 under different Shared Socio-economic Pathways(SSPs).Moreover,the water demand in the north and south of the Qinling Mountains from 2019 to 2100 was analyzed by constructing a system dynamic *** results show that the mean annual runoff in the southern and northern slopes of the Qinling Mountains from 1970 to 2015 were 21.5×10^(9) and 3.52×10^(9) m^(3),*** the SSP1-2.6,SSP2-4.5,SSP3-7.0,and SSP5-8.5 scenarios from 2015 to 2100,the mean annual runoff in the southern(northern)slope will increase by 2.9(1.5),2.0(1.4),2.7(1.6),and-2.1(0.4)×10^(9) m^(3),*** mean annual water consumption in the northern foothills of the Qinling Mountains for Baoji,Xi’an,and weinan cities is projected to increase from 4.1×10^(9) m^(3) in 2015 to 7.6×10^(9) m^(3) in 2100,while that in the southern foothills for Hanzhong,Ankang,and Shangluo cites is projected to increase from 2.7×10^(9) m^(3) in 2015 to 4.8×10^(9) m^(3) in ***,runoff in the southern slope is much larger than the water demand in the southern *** increase of runoff in the northern slope cannot satisfy the water demand in the northern ***,the South-to-North Water Transfer project is proposed for meeting the water demand in the northern *** the premise of ensuring downstream water demand,approximately 10.5×10^(9) m^(3) of water resources can be transferred from the southern slope to the weihe River and the Beijing-Tianjin-Hebei-Henan regions under SSP1-2.6,but only 3.9×10^(9) m^(3) can be transferred under SSP5-8.5.

关键词： Qinling Mountains Climate change Runoff Hydrological model CMIP6 System Dynamics

Synthesis of diethers derived from furoin by phase transfer catalysis under microwave irradiation

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Chinese Chemical Letters 2007年第7期18卷 791-794页

作者： Feng Zhang Ya Zhuo li da wei Gao Ji Kui Sun Yu Min Zhang College of Chemistry Jilin University Changchun Jilin 130012 China

A series of new diethers were obtained by alkylation of furoin under microwave irradiation （MWI） in phase transfer catalysis （PTC） conditions. The products of alkyl halides were synthesized in good yields （〉75%） within a few minutes, and the products of dihalides were synthesized in fair yields （about 45%）. The yields are dramatically improved compared to conventional heating under the same conditions, in spite of similar profiles of rising in temperature.

关键词： Microwave irradiation Furoin Phase transfer catalysis O-Alkylation

Fabrication of a Bi-layer Tubular Scaffold Consisted of a Dense Nanofibrous Inner Layer and a Porous Nanoyarn Outer Layer for Vascular Tissue Engineering

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Journal of Donghua University(English Edition) 2014年第5期31卷 718-722页

作者： CHEN Jian-feng liU wei WU Tong li da-wei ZHANG Jian-guang WANG Nan-ping MO Xiu-mei State KeyLaboratory for Modifications of Chemical Fibers and Polymer Materials- Coilege of Material Science and EngineeringDonghua University Shanghai 201620 China Biomaterials and Tissue Engineering Laboratory College of Chemistry Chemical Engineering and Biotechnology DonghuaUniversity Shanghai 201620 China Shanghai Fisheries Research Institute Shanghai 201620 China

Recent years, it has attracted more attentions to increase the porosity and pore size of nanofibrous scaffolds to provide the for the cells to grow into the small-diameter vascular grafts. In this study, a novel bi-layer tubular scaffold with an inner layer and an outer layer was fabricated. The inner layer was random collagen/poly （ L-lactide-co-caprolactone ） I P （ LLA- CL） ] nanofibrous mat fabricated by conventional electrospinning and the outer layer was aligned collagen/P （LLA-CL） nanoyarns prepared by a dynamic liquid dectrospinning method. Fourier transform infrared spectroscopy （FTIR） was used to characterize the chemical structure. Scanning electron microscopy （ SEM ） was employed to observe the morphology of the layers and the cross- sectioned bi-layer tubular scaffold. A liquid displacement method was employed to measure the porosities of the inner and outer layers. Stress-strain curves were obtained to evaluate the mechanical properties of the two different layers and the bi-layer membrane. The diameters of the nanofibers and the nanoyarns were （480 ± 197 ） nm and （ 19.66 ± 4.05 ） μm, respectively. The outer layer had a significantly higher porosity and a larger pore size than those of the inner layer. Furthermore, the bi-layer membrane showed a good mechanical property which was suitable as small-diameter vascular graft. The results indicated that the bi-layer tubular scaffold had a great potential application in small vascular tissue engineering.

关键词： nanoyarn poly ( L-lactide-co-caprolactone ) [ P ( LLA-CL ) ] bi-layer tubular scaffold porous structure small vascular tissueengineering

Characteristics of 355nm Laser damage in Bulk Materials

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Chinese Physics Letters 2013年第6期30卷 194-196页

作者： YU Zhen-Kun HE Hong-Bo QI Hong-Ji FANG Zhou li da-wei Key Laboratory of Materials for High Power Lasers Shanghai Institute of Optics and Fine MechanicsShanghai 201800 University of Chinese Academy of Sciences Beijing 100049

The laser damage resistances of four crystals(CaF_(2),MgF_(2),Al_(2)O_(3),and SiO_(2))and fused silica(JGS1)irradiated at 355nm(8 ns,300-on-1)are *** laser-induced damage threshold is measured using a tripled Nd:YAG laser *** results obtained from the pure crystals are in accordance with their specific optical,mechanical,and thermal *** empirical law based on the Franz–Keldysh effect can interpret the experimental results.

关键词： Nd:YAG 355nm laser