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Characteristics of long period microtremor and validation of microtremor array measurements in inland areas of China

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Journal of Mountain Science 2016年第11期13卷 1910-1922页

作者： CHE Ai-lan ZHANG Teng-yu FENG Shao-kong School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University 800 Dongchuan-Road Shanghai 200240 China

To study the characteristics of long period microtremor and applicability of microtremor survey,we have made microtremor observations using long period seismometers of the China's mainland from coastal cities like Shanghai and Tianjin through Beijing,Xi'an,to the far inland cities of lanzhou and *** observation shows that the level of power spectrum of long period microtremors reduced rapidly from the coast to the inland ***,the energy of long period microtremors in Beijing,Xi'an,lanzhou and Tianshui area are only approximately ten-thousandth to thousandth of that in *** at the complexity of the underground structure in the far inland,a series of underground structure models with different distributions were assessed using three-dimensional,dynamic finite element method(FEM) *** results were used to evaluate microtremor survey methods and their limitations with regard to aggregate variability and thickness ***-wave reflections between layers with the change of underground structure distribution occurred,which have significant effect on the performance of the different field *** over a broad spectrum from which velocity-depth profiles were produced via inversion *** the thickness nor the shear waveVelocity V of the subsurface layer inversion results appeared over a large evaluation with increasing slope *** particular,when the angle of the model reached 45°,it could not be accurately evaluated using one-dimensional inversion ***,the array microtremor survey(AMS) was carried out in Shanghai City,*** AMS techniques do not have the layer sensitivity or accuracy(velocity and layer thickness) of borehole techniques,the obtained shear wave velocity structure is especially useful for earthquake disaster prevention and seismic analysis.

关键词： Long period microtremor Array Microtremor survey Power spectrum Inversion S-wave velocity structure

Lacticaseibacillus rhamnosus Probio-M9 may be vertically transmitted from mother to infant during lactation based on faeces metagenomics

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Food Science and Human Wellness 2024年第2期13卷 721-728页

作者： lan Yang Lai-yu Kwok Zhihong Sun Heping Zhang Key Laboratory of Dairy Biotechnology and Engineering Ministry of EducationInner Mongolia Agricultural UniversityHohhot 010018China Key Laboratory of Dairy Products Processing Ministry of Agriculture and Rural AffairsInner Mongolia Agricultural UniversityHohhot 010018China Inner Mongolia Key Laboratory of Dairy Biotechnology and Engineering Inner Mongolia Agricultural UniversityHohhot 010018China

Probiotics exert beneficial effects on the *** study aimed to investigate whether maternally ingested Lacticaseibacillus rhamnosus Probio-M9 during pregnancy could access and colonize the infant *** study recruited one pregnant woman,who ingested Probio-M9 daily from 35 weeks of gestation to *** of the mother-infant pair were regularly collected from one month before delivery to 6 months of infant's age for metagenomic ***-M9 genomes were mappable to all infant fecal samples,suggesting the ingested probiotics could be vertically transmitted from mother to ***-or mother-specific differential metabolic pathways were found between the maternal and infant's gut microbiome,implicating apparent differences in the intestinal metagenomic potential/function between the mother and the *** conclusion,maternal ingestion of Probio-M9 during the final weeks of gestation could deliver to the infant *** findings provided novel insights into shaping infant's gut microbiota.

关键词： Metagenomic analysis Lacticaseibacillus rhamnosus Gut microbiome Mother Infant

Electronic Nose with an Air Sensor Matrix for Detecting Beef Freshness

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Journal of Bionic Engineering 2008年第1期5卷 67-73页

作者： Zhe Zhang Jin Tong Dong-hui Chen yu-bin lan Key Laboratory of Terrain-Machine Bionics Engineering （Ministry of Education China） Jilin University Changchun 130022 P. R. China Aerial Application Technology USDA-ARS-SPARC-APMRU College Station TX 77845 USA

China is one of the largest meat producing countries in the wodd. With the growing concern for food safety more attention has been paid to meat quality. The application of conventional test methods for meat quality is limited by many factors, and subjectiveness, such as longer time to prepare samples and to test. A sensor matrix was constructed with several separate air sensors, and tests were conducted to detect the freshness of the beef. The results show that the air sensors TGS2610, TGS2600, TGS2611, TGS2620 and TGS2602 made by Tianjin Figaro Electronic Co, Ltd could be used to determine the degree of freshness but TGS2442 is not suitable. This study provides a foundation for designing and making an economical and practical detector for beef freshness.

关键词： gas sensitive sensor matrix degree of beef freshness electronic nose

Optical monitoring and IDV analysis of the blazars S50716+714 and 3C 273

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Research in Astronomy and Astrophysics 2021年第4期21卷 297-310页

作者： Xiao-lan Liu yu-Hai yuan Hong-Ren Huang Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006China

S50716+714 and 3C 273 are frequently studied blazars,which show obvious optical variabilities with different *** the 1.0 m telescope at the yunnan Observatory,we monitored the two *** S50716+714,we report 990 observations during the monitoring duration from JD 2458536 to JD *** 3C 273,there are 884 observations during the monitoring duration from JD 2458539 to *** on those observations,we obtain the following results.(1)For S50716+714,there lie intraday optical variabilities(IDVs),with timescales from 0.31 hours to 2.64 *** 3C 273,it is possible that there lie IDVs,with timescales from 0.36 hours to 0.49 hours.(2)The time delay of S50716+714 isτRI=3.46 min between R and I bands,and the time delay of 3C273 isτIV=6.42 min between I and V bands.(3)We find that,for S50716+714,there lies a suspected intra-day period,P≈185.78 min;for 3C273,there lie intra-day periods,which are about~60 min and~80 min.

关键词： quasars:general quasars:individual(S50716+714 3C 273) galaxies:photometry

Variations in monsoon precipitation over southwest China during the last 1500 years and possible driving forces

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Science China Earth Sciences 2022年第5期65卷 949-965页

作者： Bin LIU Enguo SHENG Keke yu Kang’en ZHOU Jianghu lan College of Resources and Environment Zunyi Normal UniversityZunyi 563006China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Shaanxi Key Laboratory of Disasters Monitoring&Mechanism Simulation Baoji University of Arts and SciencesBaoji 721013China School of Earth System Science Institute of Surface-Earth System ScienceTianjin UniversityTianjin 300072China

Understanding hydroclimatic patterns and their possible driving mechanisms during distinct climate periods over the last 1500 years—such as the Medieval Warm Period(MWP),the Little Ice Age(LIA),and the Current Warm Period—is crucial for predicting future changes to monsoon precipitation in southwest China under global warming *** this study,based on ^(210)Pb and ^(137)Cs dating of surface sediments and AMS ^(14)C dating of terrestrial plant residues,we establish a robust age model that covers the last~1500 years(AD 439–2012)at Lake Yihai in southwest *** use analyses of multiple geochemical proxy indices,including loss on ignition at 550℃,total organic carbon,total nitrogen,C/N ratios,and stable carbon isotopes of organic matter to reconstruct changes in summer monsoon precipitation at Lake Yihai during the last~1500 *** results show that,over southwest China,warm and dry climate conditions prevailed during the MWP(AD 1000–1400)and the past 200 years,whereas conditions during the LIA(AD 1400–1800)were cold and *** is consistent with evidence from other geological records over southwest China,such as stalagmite and lake sediment *** hydroclimatic patterns have occurred over the last 1500 years in adjacent tropical/subtropical monsoon regions where the climate is similarly dominated by the Indian summer monsoon(e.g.,South China,the South China Sea,Southeast Asia,Northeast India).We suggest that the meridional migration of the mean position of the Inter-tropical Convergence Zone,and El Niño/Southern Oscillation conditions which are linked to tropical Pacific sea surface temperature,are responsible for centennial-scale hydroclimatic patterns over southwest China and adjacent areas during the last 1500 years.

关键词： Lake sediments Southwest China Monsoon precipitation Distinct climate periods Inter-tropical Convergence Zone

The inverse problem for differential pencils on a star-shaped graph with mixed spectral data

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Science China Mathematics 2020年第8期63卷 1559-1570页

作者： yu Ping Wang Natalia Bondarenko chung Tsun Shieh Department of Applied Mathematics Nanjing Forestry UniversityNanjing 210037China Department of Applied Mathematics and Physics Samara National Research UniversitySamara 443086Russia Department of Mathematics Tamkang UniversityNew Taipei City 25137China

The partial inverse problem for differential pencils on a star-shaped graph is studied from mixed spectral *** precisely,we show that if the potentials on all edges on the star-shaped graph but one are known a priori then the unknown potential on the remaining edge can be uniquely determined by partial information on the potential and a part of eigenvalues.

关键词： inverse spectral problem differential pencils potential star-shaped graph

Thermoresponsive block copolymer supported Pt nanocatalysts for base-free aerobic oxidation of 5-hydroxymethyl-2-furfural

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Frontiers of Chemical Science and Engineering 2021年第6期15卷 1514-1523页

作者： Huaxin Qu Jie Deng Bei Wang Lezi Ouyang Yong Tang Kai yu lan-lan Lou Shuangxi Liu Institute of New Catalytic Materials Science School of Materials Science and EngineeringNational Institute for Advanced MaterialsNankai UniversityTianjin300350China MOE Key Laboratory of Pollution Processes and Environmental Criteria and Tianjin Key Laboratory of Environmental Technology for Complex Transmedia Pollution College of Environmental Science and EngineeringNankai UniversityTianjin300350China MOE Key Laboratory of Advanced Energy Materials Chemistry Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Tianjin300072China

A base-free catalytic system for the aerobic oxidation of 5-hydroxymethyl-2-furfural was exploited by using Pt nanoparticles immobilized onto a thermoresponsive poly(acrylamide-co-acrylonitrile)-b-poly(N-vinylimidazole)block copolymer,with an upper critical solution temperature of about 45°*** Pt nanocatalysts were well-dispersed and highly active for the base-free oxidation of 5-hydroxymethyl-2-furfural by molecular oxygen in water,affording high yields of 2,5-furandicarboxylic acid(up to>99.9%).The imidazole groups in the block copolymer were conducive to the improvement of catalytic ***,the catalysts could be easily separated and recovered based on their thermosensitivity by cooling the reaction system below the upper critical solution *** stability and reusability were observed over these copolymer-immobilized catalysts with no obvious decrease in catalytic activity in the five consecutive cycles.

关键词： aerobic oxidation base-free 5-hydroxymethyl-2-furfural Pt nanoparticle thermoresponsive block copolymer

Compatibility of rubber stoppers for recombinant antitumor-antivirus protein injection by gas chromatography-mass spectrometry

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Journal of Pharmaceutical Analysis 2019年第3期9卷 178-184页

作者： Zhaorui Meng Xun Gao Haifeng yu lan Zhang Xiangyong yu Longshan Zhao School of Pharmacy Shenyang Pharmaceutical University Shenyang 110016 China Anshan Institute for Food and Drug Control Anshan 114006 China Shenyang Wellwolf Pharmaceutical Science and Technology Co. Ltd Shenyang 110022 China

A simple, rapid, and sensitive gas chromatography-mass spectrometry (GC-MS) method was developed and validated for the simultaneous determination of two fatty acids, methyl hexadecanoate (MH) and methyl stearate (MS), to allow the evaluation of packaging-drug compatibility. The two migrants were quantified in selective ion-monitoring (SIM) mode, with limits of detection (LOD) of 0.0030 μg/mL and 0.0121 μg/mL. Linear calibration curves for MH and MS were obtained in the concentration ranges of 0.1011–5.0570 μg/mL and 0.2015–10.0740 μg/mL, respectively. The developed method was successfully applied to estimate the safety of the injection of recombinant antitumor-antivirus protein (RAAP). The results showed that the possible maximum daily intake was 3.0 ng and 12.1 ng for MH and MS, respectively. As these values were both below the permitted daily exposure, the migrants can be considered as having low safety risk and do not affect the quality of the injection.

关键词： Compatibility Rubber stoppers Injection Fatty acids GC-MS

基于储能型智能软开关联合网络重构的配电网供电恢复策略

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湖南工业大学学报 2025年第1期39卷 35-42页

作者：喻希杨杉兰征高芷蓉湖南工业大学电气与信息工程学院湖南株洲412007

为应对自然灾害、网路攻击等极端事件导致的停电事故,并降低电网的失负荷率与经济损失,提出了一种极端事件下储能型智能软开关(energy storage integrated soft open point,E-SOP)联合网络重构的主动配电网供电恢复策略。首先,介绍了E-... 详细信息

为应对自然灾害、网路攻击等极端事件导致的停电事故,并降低电网的失负荷率与经济损失,提出了一种极端事件下储能型智能软开关(energy storage integrated soft open point,E-SOP)联合网络重构的主动配电网供电恢复策略。首先,介绍了E-SOP接入配网的拓扑结构示意图,并建立其在故障恢复下的数学模型。其次,考虑三级负荷的重要程度和网络损耗,以配网各节点损失程度和网络损失最小为目标函数,构建E-SOP和网络重构联合进行供电恢复的运行模型,实现极端事件下主动配电网的快速恢复。最后,以改进的IEEE33节点配电网为例分别研究了E-SOP安装容量、位置、数量等参数对电网恢复能力的影响,并对其供电恢复策略进行验证分析。研究结果表明:所提策略可减少配电网故障下的失负荷率,进一步提升供电恢复水平。

关键词：极端事件储能型智能软开关供电恢复策略网络重构