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Simultaneous Screening of 733 Pesticide Residues in Fruits and Vegetables by a GC/LC-Q-TOFMS Combination Technique

Engineering 2020年第4期6卷 432-441页

作者： guofang pang Qiaoying Chang Ruobin Bai Chunlin Fan Zijuan Zhang Hongyuan Yan Xingqiang Wu Chinese Academy of Inspection and Quarantine Beijing 100176China College of Chemistry and Environmental Science Hebei UniversityBaoding 071002China Beijing Uni-Star Inspection Technology Co.Ltd. Beijing 100176China

In this paper,we report the construction of two accurate mass databases and the development of a combination detection method that simultaneously screens for 733 pesticide and chemical contaminant multi-residues via high-throughput liquid chromatography(LC)-and gas chromatography(GC)-quadru pole-time-of-flight mass spectrometry(Q-TOFMS).This work demonstrates that electronic mass spectral standards may replace chemical-source standard materials as references through one sample preparation and the combination of GC/LC-Q-TOFMS *** cutting-edge technique has also replaced multiresidue determination using targeted detection with non-targeted *** pesticide residue types,sensitivity,recovery,and reproducibility of this combination technique are evaluated in eight fruit and vegetable *** technique shows three advantages:①In comparison with the discovery capability of a single technique,the combination technique shows an improvement of 51.1%(GC-QTOFMS)and 39.6%(LC-Q-TOFMS),respectively;②the combination technique can satisfy a screening limit lower than 10μg·kg^-1 and meet the requirements of“uniform standards,”although some of the pesticide residues could be optimized to further improve screening sensitivity;③over 488 pesticides with recoveries between 60%-120%and relative standard deviation(RSD)<20%at a spiked level of 10μg·kg^-1 were detected with the combination technique in eight different *** 2012 to 2017,this combination technique was applied in an investigation to screen pesticide residues from 1384 sampling locations for 38138 batched samples covering 18 categories and 134 types of fruits and vegetables obtained from across the mainland of *** statistical analysis,533 pesticides in 115891 determinations were detected,and the regularity of pesticides in the fruits and vegetables sold on the Chinese market was shown.

关键词： Pesticide multi-residues GC-Q-TOFMS LC-Q-TOFMS Accurate mass database Spectra library Fruits and vegetables

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Minimal Legendrian surfaces in the tangent sphere bundle of R3

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Science China Mathematics 2024年第11期67卷 2607-2628页

作者： Mingyan Li guofang Wang School of Mathematical Sciences Ocean University of China Mathematisches Institut Albert-Ludwigs-Universit?t Freiburg

In this paper,we study minimal Legendrian surfaces Σ immersed in the tangent sphere bundle *** classify(1) totally geodesic Legendrian surfaces,(2) closed minimal Legendrian surfaces of genus smaller than or equal to 1 and complete minimal Legendrian surfaces with the non-negative Gauss curvature,and(3) complete stable minimal Legendrian surfaces.

关键词： 53C24 53C42 classification Legendrian surface stable minimal surface tangent sphere bundle

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From tunnel boring machine to tunnel boring robot: perspectives on intelligent shield machine and its smart operation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 357-381页

作者： Yakun ZHANG guofang GONG Huayong YANG Jianbin LI Liujie JING State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310058China China Railway Engineering Equipment Group Co. Lid.Zhengzhou 450016China Maha Fluid Power Research Center Purdue UniversityWest LafayetteIN 47905USA

Advances in intelligent shield machines reflect an evolving trend from traditional tunnel boring machines(TBMs)to tunnel boring robots(TBRs).This shift aims to address the challenges encountered by the conventional shield machine industry arising from construction environment and manual *** study presents a systematic review of intelligent shield machine technology,with a particular emphasis on its smart ***,the definition,meaning,contents,and development modes of intelligent shield machines are *** development status of the intelligent shield machine and its smart operation are then *** analyzing the operation process of the shield machine,an autonomous operation framework considering both stand-alone and fleet levels is *** and recommendations are given for achieving autonomous *** study offers insights into the essence and developmental framework of intelligent shield machines to propel the advancement of this technology.

关键词： Intelligent shield machine Tunnel boring machine(TBM) Tunnel boring robot(TBR) Self-driving Autonomous control Shield machine

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APOE and APOC1 gene polymorphisms are associated with cognitive impairment progression in Chinese patients with late-onset Alzheimer's disease

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Neural Regeneration Research 2014年第6期9卷 653-660页

作者： Qin Zhou Dantao Peng Xinrui Yuan Zeping Lv Shenghang pang Wenyu Jiang Chuyu Yang Xiaohong Shi guofang pang Yige Yang Haiqun Xie Wandong Zhang Caiyou Hu Ze Yang Key Laboratory of Geriatrics Beijing Hospital & Beijing Institute of Geriatrics Ministry of Health Department of Neurology Jiangbin Hospital Nanning Human Health Therapeutics National Research Council of Canada

Current evidence shows that apolipoprotein E （APOE）, apolipoprotein CI （APOC1） and low density lipoprotein receptor-related protein （LRP） variations are related to late-onset Alzheimer＇s disease. However, it remains unclear if genetic polymorphisms in these genes are associated with cognitive decline in late-onset Alzheimer＇s disease patients. We performed a 30-month longitudi- nal cohort study to investigate the relationship between Alzheimer＇s disease and APOE, APOC1, and LRP. In this study, 78 Chinese Han patients with late-onset Alzheimer＇s disease were recruit- ed form Guangxi Zhuang Autonomous Region in China. APOE, APOC1, and LRP genotyping was performed using polymerase chain reaction-restriction fragment length polymorphisms. The Mini-Mental State Examination and Clinical Dementia Rating Scale were used to assess pa- tients＇ cognitive function. After a 30-month follow-up period, we found a significant reduction in Mini-Mental State Examination total score, a higher proportion of patients fulfilling cognitive impairment progression criteria, and a higher proportion of APOC1 H2 carriers in APOE 4 carriers compared with non-carriers. In addition, the APOE 4 allele frequency was significantly higher in the cognitive impairment progression group compared with the non-cognitive im- pairment progression group. In conclusion, APOE e4 plays an important role in augmenting cognitive decline, and APOC1 H2 may act synergistically with APOE ~4 in increasing the risk of cognitive decline in Chinese patients with late-onset Alzheimer＇s disease.

关键词： nerve degeneration cognitive disorders dementia Alzheimer's disease polymorphism apolipoprotein E apolipoprotein CI low density lipoprotein receptor-related protein NSFC grant neural regeneration

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亚慢性暴露3-氯-1,2-丙二醇对雄性大鼠生殖系统的影响

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中国食品学报 2019年第5期19卷 39-44页

作者：邢寒竹方冰常巧英庞国芳中国农业大学北京食品营养与人类健康高精尖创新中心北京100083

3-氯-1,2-丙二醇(3-MCPD)是公认的食品污染物。本文通过亚慢性暴露3-MCPD,研究其对雄性大鼠生殖系统的影响。结果表明,5.0 mg/kg 3-MCPD虽不影响大鼠生长,但精子总浓度和直线运动精子比例显著降低(P<0.05),不同剂量染毒均引起睾丸生精... 详细信息

3-氯-1,2-丙二醇(3-MCPD)是公认的食品污染物。本文通过亚慢性暴露3-MCPD,研究其对雄性大鼠生殖系统的影响。结果表明,5.0 mg/kg 3-MCPD虽不影响大鼠生长,但精子总浓度和直线运动精子比例显著降低(P<0.05),不同剂量染毒均引起睾丸生精上皮细胞脱落,曲细精管直径明显缩小(P<0.05);与对照组相比,血清孕酮含量显著下降(P<0.05),血清睾酮含量随着染毒剂量的增加呈下降趋势;3-MCPD染毒还增加了曲细精管内生精细胞的凋亡。本试验结果表明:低剂量3-MCPD染毒可损伤雄性大鼠生殖系统。

关键词： 3-MCPD 亚慢性暴露精子性激素睾丸细胞

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Enhanced wear prediction of tunnel boring machine disc cutters for accurate remaining useful life estimation using a hybrid model

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 642-662页

作者： Xinghai ZHOU Yakun ZHANG guofang GONG Huayong YANG Qiaosong CHEN Yuxi CHEN Zhixue SU The State Key Laboratory of Fluid Power&Mechatronic Systems Zhejiang UniversityHangzhou 310027China Guangzhou Rail Transit Construction Engineering Consulting Co. Ltd.Guangzhou 510000China China Railway Engineering Equipment Group Co. Ltd.Zhengzhou 450016China

In tunnel construction with tunnel boring machines(TBMs),accurate prediction of the remaining useful life(RUL)of disc cutters is critical for timely maintenance and replacement to avoid delays and cost *** paper introduces a novel hybrid model,integrating fundamental and data-driven approaches,to enhance wear prediction of TBM disc cutters and enable accurate RUL *** fundamental model is improved by incorporating composite wear mechanisms and load estimation techniques,showcasing superior prediction accuracy compared to single-mechanism ***,the hybrid model innovatively incorporates a data-driven supplementary residual term into the improved fundamental model,leading to a high-performance wear prediction *** actual field data from a highway tunnel project in Shenzhen,the performance of the hybrid model is rigorously tested and compared with pure fundamental and data-driven *** hybrid model outperforms the other models,achieving the highest accuracy in predicting TBM disc cutter wear(mean absolute error(MAE)=0.53,root mean square error(RMSE)=0.64).Furthermore,this study thoroughly analyzes the hybrid model’s generalization capability,revealing significant impacts of geological conditions on prediction *** model’s generalization capability is also improved by expanding and updating the data *** RUL estimation results provided by the hybrid model are straightforward and effective,making it a valuable tool by which construction staff can monitor TBM disc cutters.

关键词： tunnel boring machine disc cutter wear prediction remaining useful life field data hybrid model

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A privacy-preserving data aggregation system based on blockchain in VANET

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BLOCKCHAIN-RESEARCH AND APPLICATIONS 2024年第3期5卷 140-152页

作者： Yang, Ruicheng Dong, guofang Xu, Zhengnan Ning, Juangui Du, Jianming Yunnan Minzu Univ Sch Elect Informat Technol Kunming 650500 Peoples R China Yunnan Key Lab Unmanned Autonomous Syst Kunming 650500 Peoples R China

In the realm of vehicular ad hoc networks (VANETs), data aggregation plays a pivotal role in bringing together data from multiple vehicles for further processing and sharing. Erroneous data feedback can significantly impact vehicle operations, control, and overall safety, necessitating the assurance of security in vehicular data aggregation. Addressing the security risks and challenges inherent in data aggregation within VANETs, this paper introduces a blockchain-based scheme for secure and anonymous data aggregation. The proposed scheme integrates cloud computing with blockchain technology, presenting a novel blockchain-based data aggregation system that robustly supports efficient and secure data collection in VANETs. Leveraging key escrow resilience mechanisms, the solution ensures the security of system keys, preventing the security problems caused by keys generated by third parties alone in the past. Furthermore, through secondary data aggregation, fine-grained data aggregation is achieved, providing effective support for cloud services in VANETs. The effectiveness of the proposed scheme is confirmed through security analysis and performance evaluations, demonstrating superior computational and communication efficiency compared existing alternatives.

关键词： Vehicular ad hoc networks Data aggregation Blockchain Key escrow resilience Anonymity SCHEME AUTHENTICATION SECURITY

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Minimal Legendrian surfaces in the tangent sphere bundle of ■

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Science China Mathematics 2024年

作者： Mingyan Li guofang Wang School of Mathematical Sciences Ocean University of China Mathematisches Institut Albert-Ludwigs-Universit?t Freiburg

In this paper, we study minimal Legendrian surfaces Σ immersed in the tangent sphere bundle T1■3. We classify（1） totally geodesic Legendrian surfaces,（2） closed minimal Legendrian surfaces of genus smaller than or equal to 1 and complete minimal Legendrian surfaces with the non-negative Gauss curvature,and（3） complete stable minimal Legendrian surfaces.

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液相色谱-串联质谱法快速筛查测定浓缩果蔬汁中的156种农药残留

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色谱 2009年第2期27卷 127-137页

作者：李岩郑锋王明林庞国芳山东农业大学食品科学与工程学院山东泰安271018 秦皇岛出入境检验检疫局河北秦皇岛066002

建立了浓缩果蔬汁中156种农药多残留的液相色谱-电喷雾串联质谱（LC-ESI-MS/MS）测定方法。样品用1%醋酸乙腈溶液萃取,经Waters Sep-Pak Vac固相萃取柱净化,乙腈-甲苯（体积比为3∶1）洗脱,旋转蒸发浓缩,用乙腈-水（体积比为3∶2）溶解,... 详细信息

建立了浓缩果蔬汁中156种农药多残留的液相色谱-电喷雾串联质谱（LC-ESI-MS/MS）测定方法。样品用1%醋酸乙腈溶液萃取,经Waters Sep-Pak Vac固相萃取柱净化,乙腈-甲苯（体积比为3∶1）洗脱,旋转蒸发浓缩,用乙腈-水（体积比为3∶2）溶解,以Agilent ZORBAX SB-C18色谱柱分离,以电喷雾电离串联质谱在正离子多反应监测（MRM）模式下进行测定。对156种农药在5种浓缩果蔬汁（橙汁、苹果汁、葡萄汁、白菜汁、胡萝卜汁）中两个添加水平下的回收率进行了测定,回收率范围为57.2%～122.7%,相对标准偏差范围为0.9%～19.8%。方法的检出限（S/N=3）和定量限（S/N=10）范围分别为0.10～56.77μg/kg和0.33～189.23μg/kg。该方法样品前处理简单、快速、分析时间短,灵敏度、准确度和精密度均符合农药多残留检测技术的要求,适用于苹果汁、橙汁、葡萄汁、白菜汁、胡萝卜汁等浓缩果蔬汁中156种农药多残留的快速筛查测定。

关键词：液相色谱-串联质谱 QuEChERS方法农药多残留浓缩果蔬汁

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液相色谱-电喷雾串联质谱法测定生姜中的215种农药残留

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色谱 2010年第6期28卷 579-589页

作者：曹静庞国芳王明林范春林山东农业大学食品科学与工程学院山东泰安271018 中国检验检疫科学研究院北京100123

建立了生姜中215种农药多残留测定的液相色谱-电喷雾串联质谱(LC-ESI-MS/MS)方法。样品用1%醋酸-乙腈溶液均质提取,经Sep-Pak Vac固相萃取柱净化,乙腈-甲苯(3∶1,v/v)洗脱,旋转蒸发浓缩至约0.5mL后,于室温氮气吹干,用乙腈-水(3∶2,v/v)... 详细信息

建立了生姜中215种农药多残留测定的液相色谱-电喷雾串联质谱(LC-ESI-MS/MS)方法。样品用1%醋酸-乙腈溶液均质提取,经Sep-Pak Vac固相萃取柱净化,乙腈-甲苯(3∶1,v/v)洗脱,旋转蒸发浓缩至约0.5mL后,于室温氮气吹干,用乙腈-水(3∶2,v/v)溶解,以电喷雾电离串联质谱在正离子多反应监测(MRM)模式下进行测定。在定量限水平进行添加回收率实验,方法的回收率范围为68.1%～132.6%,其中回收率在70%～120%的占94.4%,相对标准偏差(RSD)范围为0.4%～25.0%。方法的检出限(S/N=3)和定量限(S/N=10)范围分别为0.01～70.45μg/L和0.04～234.84μg/L。该方法操作简便,灵敏度、准确度和精密度均符合农药多残留检测技术要求,适用于生姜中215种农药多残留的快速测定。

关键词：液相色谱-电喷雾串联质谱农药多残留生姜

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