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改良SinChERS结合电喷雾离子源-三重四级杆质谱测定茶叶中灭螨醌及其代谢物的方法研究

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食品科技 2024年第7期49卷 308-314页

作者：苏敏钟世欢王静叶佳明黄南杨天明陆梅阳浙江公正检验中心有限公司浙江杭州310000 浙江省食品安全重点实验室浙江杭州310000

文章建立了一种基于SinChERS净化技术结合超高压液相色谱-串联质谱法测定茶叶中灭螨醌及其代谢物羟基灭螨醌残留量的检测方法。样品经1%甲酸乙腈提取,用SinChERS-TPR进行净化,经Agilent C18色谱柱分离,以0.1%甲酸水-甲醇作为流动相进行... 详细信息

文章建立了一种基于SinChERS净化技术结合超高压液相色谱-串联质谱法测定茶叶中灭螨醌及其代谢物羟基灭螨醌残留量的检测方法。样品经1%甲酸乙腈提取,用SinChERS-TPR进行净化,经Agilent C18色谱柱分离,以0.1%甲酸水-甲醇作为流动相进行梯度洗脱,电喷雾离子源,正离子模式,多反应监测模式检测,基质匹配工作曲线外标法定量。灭螨醌和羟基灭螨醌在0.200~20.0 ng/mL范围内线性良好,相关系数均大于0.999。灭螨醌检出限为1.25μg/kg,羟基灭螨醌检出限为0.5μg/kg;灭螨醌定量限为4μg/kg,羟基灭螨醌定量限为2μg/kg。灭螨醌和羟基灭螨醌三水平的加标回收率为77.0%~100.2%,相对标准偏差1.7%~7.8%。该方法操作简便、快速准确,适用于茶叶中灭螨醌及其代谢物的批量测定。

关键词：灭螨醌羟基灭螨醌茶叶 SinChERS

分散固相萃取-液相色谱-串联质谱法测定不同品种柑橘果实不同部位中3种柠檬苦素类似物的含量

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理化检验（化学分册） 2024年第2期60卷 171-179页

作者：秦芸桦钟世欢陈青俊王京王岳叶佳明陈云义孙崇德赞宇科技集团股份有限公司杭州310030 浙江公正检验中心有限公司杭州311305 浙江省食品安全重点实验室杭州310009 浙江大学果实品质生物学实验室杭州310058

提出了分散固相萃取-液相色谱-串联质谱法同时测定4个品种柑橘果实的4个部位(油胞层、白皮层、囊衣、果肉)中柠檬苦素、诺米林、黄柏酮含量的方法。取5.0 g均质后的样品,加入5 mL水,涡旋混匀后加入20 mL体积比5∶5的丙酮-乙腈混合溶液,... 详细信息

提出了分散固相萃取-液相色谱-串联质谱法同时测定4个品种柑橘果实的4个部位(油胞层、白皮层、囊衣、果肉)中柠檬苦素、诺米林、黄柏酮含量的方法。取5.0 g均质后的样品,加入5 mL水,涡旋混匀后加入20 mL体积比5∶5的丙酮-乙腈混合溶液,混匀后超声提取10 min,离心5 min。用3 mL水活化2 g EMR-Lipid吸附剂,加至上清液中,涡旋30 s,加入5 g质量比1∶4的氯化钠-硫酸镁混合物和15 mg石墨化碳黑,迅速摇匀后离心1 min。吸取全部上清液,于40℃氮吹至近干,残渣用10.0 mL体积比9∶1的0.1%(体积分数,下同)甲酸溶液和乙腈的混合溶液复溶,过0.22μm滤膜,滤液按照优化的仪器工作条件测定。进行色谱分析时,以CAPCELL PAK ADME HR色谱柱作固定相,以不同体积比的0.1%甲酸溶液和乙腈的混合溶液作流动相进行梯度洗脱分离;进行质谱分析时,以电喷雾离子源正离子(ESI+)和多反应监测(MRM)模式检测。结果显示:3种柠檬苦素类似物的质量浓度在0.10~10.0 mg·L^(-1)内和对应的峰面积呈线性关系,检出限(3S/N)均为0.01 mg·kg^(-1);按标准加入法进行回收试验,回收率为83.1%~90.5%,测定值的相对标准偏差(n=6)为2.6%~5.6%;方法用于30个实际样品的分析,柠檬苦素类似物在不同品种柑橘果实及其不同部位中的含量分布差异显著,柚类品种中柠檬苦素类似物总测定值较高且主要分布在囊衣部位,其他品种主要分布在白皮层和油包层。

关键词：分散固相萃取液相色谱-串联质谱法柠檬苦素类似物分布柑橘果实

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食品中焦糖色与4-甲基咪唑的测定

食品科技 2024年第5期49卷 321-327页

作者：叶佳明钟世欢苏敏秦芸桦黄南杨天明巩启强王森燚浙江公正检验中心有限公司浙江杭州310009 赞宇科技集团股份有限公司浙江杭州310009

文章建立了高效液相色谱法测定食品中焦糖色的含量,结合超高效液相色谱-串联质谱法测定其4-甲基咪唑的含量的方法。样品加入水超声提取后,离心,上清液经MCX柱纯化后,收集初始流出液以4倍乙醇沉淀,离心后弃去上清液,沉淀以水复溶后测定... 详细信息

文章建立了高效液相色谱法测定食品中焦糖色的含量,结合超高效液相色谱-串联质谱法测定其4-甲基咪唑的含量的方法。样品加入水超声提取后,离心,上清液经MCX柱纯化后,收集初始流出液以4倍乙醇沉淀,离心后弃去上清液,沉淀以水复溶后测定焦糖色素;4-甲基咪唑收集氨水甲醇洗脱液,氮吹后以初始流动相复溶。焦糖色素以10 mmol/L磷酸二氢钠溶液为流动相,采用资生堂SCX色谱柱(4.6 mm×150 mm,5 μm),等度洗脱,610 nm波长下测定。4-甲基咪唑以含0.1%甲酸10 mmol/L乙酸铵水溶液和乙腈为流动相梯度洗脱,经资生堂HILIC色谱柱(2.1 mm×100 mm,3 μm)色谱柱分离后,采用多反应监测模式进行定量分析,内标法定量。焦糖色素与4-甲基咪唑在各自浓度范围线性良好,三水平加标回收结果显示,焦糖色素的平均回收率为80.5%~94.2%,相对标准偏差为3.3%~7.8%,固体类样品检出限为0.02 g/kg,液体类样品检出限为0.02 g/L。4-甲基咪唑的平均回收率为85.3%~106.2%,相对标准偏差为3.1%~6.9%,固体类样品检出限为1.0 μg/kg,液体类样品检出限1.0 μg/L。该方法优化前处理过程与仪器色谱条件,较好地控制了基质干扰,具有灵敏度高、重现性好、抗干扰能力强等特点,适用于酱油、米醋、可乐和黄酒等食品中焦糖色与4-甲基咪唑的检测。

关键词：焦糖色 4-甲基咪唑高效液相色谱液质联用

Insight into the Role and Evidence of Oxygen Vacancies in Porous Single-Crystalline Oxide to Enhance Catalytic Activity and Durability

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Research 2024年第2期2023卷 675-683页

作者： Lingting ye jiaming Ma Jie Zhang Wen Yin Yuanguang Xia Kui Xie Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujan Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China FuzhouFujian 350108China Advanced Energy Science and Technology Guangdong Laboratory 29 Sanxin North RoadHuizhouGuangdong 116023China Spallation Neutron Source Science Center DongguanGuangdong 523803China

Introducing and stabilizing oxygen vacancies in oxide catalysts is considered to be a promising strategy for improving catalytic activity and ***,we quantitatively create oxygen vacancies in the lattice of porous single-crystallineβ-Ga_(2)O_(3)monoliths by reduction treatments and stabilize them through the long-range ordering of crystal lattice to enhance catalytic activity and *** combination analysis of time-of-flight neutron powder diffraction and extended x-ray absorption fine structure discloses that the preferential generation of oxygen vacancy tends to occur at the site of tetrahedral coordination oxygen ions(O_(Ⅲ)sites),which contributes to the formation of unsaturated Ga-O coordination in the monoclinic *** oxygen vacancies are randomly distributed in lattice even though some of them are present in the form of domain defect in the PSC Ga_(2)O_(3)monoliths after the reduction *** number of oxygen vacancies in the reduced monoliths gives 2.32×10^(13),2.87×10^(13),and 3.45×10^(13)mg^(-1)for the Ga_(2)O_(2.952),Ga_(2)O_(2.895),and Ga_(2)O_(2.880),*** therefore demonstrate the exceptionally high C_(2)H_(4)selectivity of~100%at the C_(2)H_(6)conversion of~37%for nonoxidative dehydrogenation of C_(2)H_(6)to C_(2)H_(4).We further demonstrate the excellent durability even at 620℃for 240 h of continuous operation.

关键词： durability coordination Oxygen

Population Attributable Fractions for Modifiable Factors of Longevity and Healthy Longevity Among the Late-Elderly Aged 75 years or Older—China,1998-2018

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China CDC weekly 2023年第2期5卷 25-30,I0001-I0003页

作者： Jinhui Zhou Xiang Gao Yuan Wei Chen Chen Jun Wang Zhenwei Zhang Xinwei Li Lihong ye jiaming ye Sixin Liu Xiaochang Zhang Feng Zhao Juan Zhang Virginia Byers Kraus Yuebin Lyu Chen Mao Xiaoming Shi China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijingChina Department of Nutrition and Food Hygiene School of Public HealthInstitute of NutritionFudan UniversityShanghaiChina Department of Epidemiology and Biostatistics School of Public HealthJilin UniversityChangchunJilinChina School of Population Medicine and Public Health Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijingChina Department of Epidemiology School of Public HealthSouthern Medical UniversityGuangzhouGuangdongChina Division of Non-communicable Disease and Aging Health Management Chinese Center for Disease Control and PreventionBeijingChina Duke Molecular Physiology Institute and Division of Rheumatology Department of MedicineDuke University School of MedicineDurhamNorth CarolinaUSA Center for Global Health School of Public HealthNanjing Medical UniversityNanjingJiangsuChina

Summary What is already known about this topic?Limited evidence on healthy longevity was provided in the world,and no studies investigated the fractions of healthy longevity attributed to modifiable *** is added by this report?Incidences of longevity and healthy longevity in China are *** reveals that the total weighted population attributable fractions for lifestyles and all modifiable factors were 32.8% and 83.7% for longevity,respectively,and 30.4% and 73.4% for healthy longevity,*** are the implications for public health practice?China has a high potential for longevity and healthy *** may be targeted at education and residence in early life as well as healthy lifestyles,disease prevention,and functional optimization in late life.

关键词： prevention attributed education

Effect of rare-earth doping on the dielectric property and polarization behavior of antiferroelectric sodium niobate-based ceramics

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Journal of Materiomics 2021年第2期7卷 339-346页

作者： jiaming ye Genshui Wang Xuefeng Chen Xianlin Dong Key Laboratory of Inorganic Functional Materials and Devices Shanghai Institute of CeramicsChinese Academy of Sciences1295 Dingxi RoadShanghai200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of Sciences1295 Dingxi RoadShanghai200050China

The lead-free 0.96NaNbO_(3)-0.04CaSnO_(3) ceramics with rare-earth dopants(La,Sm and Lu)(NCLn100x)were prepared and *** is found that a certain amount of La substitution stabilizes the antiferroelectric(AFE)phase but alleviates the lattice distortion in the fresh ***-entrant-like characteristics are observed in the temperature e dielectric constant curves with the room temperature P phase gradually replaced by a possible R ***-like hysteresis loops with suppressed hysteresis loss and remanent polarization were obtained at high La content,achieving a relatively high Wre of 2.1 J/cm^(3) at a low electric field(250 kV/cm).The relaxation behaviors of the ferroelectric(FE)domain measured by piezoresponse force microscopy suggest an even long characteristic relaxation time of field-induced FE phase,which is different from the situations of other AFE *** an explanatory defected diatomic chain model,we propose that a much larger mass of substitutive ion than the origin one helps to induce low-frequency localized mode,which is believed to be in favor of the formation of polar nano-regions and hence strengthens the dynamic stability of FE phase during electric field *** research provides a further understanding of the tuning strategy for enhancing the antiferroelectricity of the NaNbO_(3)-based system.

关键词： Ceramics Rare-earth doping Phase transition Antiferroelectric

Millimeter waves in medical applications:status and prospects

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Intelligent Medicine 2024年第1期4卷 16-21页

作者： Honglin Wang Lin Lu Pengran Liu Jiayao Zhang Songxiang Liu Yi Xie Tongtong Huo Hong Zhou Mingdi Xue Ying Fang jiaming Yang Zhewei ye Department of Orthopedics Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430022China Departments of Orthopedics Renmin Hospital of Wuhan UniversityWuhanHubei 430060China

Millimeter waves are electromagnetic waves with wavelengths of 1–10 mm,which have characteristics of high frequency and short *** have gradually and widely been used in engineering and medical *** have identified studies related to millimeter waves in the biomedical field and summarized the biological effects of millimeter waves and their current status in medical ***,the shortcomings of existing studies and future developments were analyzed and discussed,with the aim of providing a reference for further research and development of millimeter waves in the medical field.

关键词： Millimeter wave Biological effects Medical applications Vital signs monitoring

Rhizoma Drynariae-derived nanovesicles reverse osteoporosis by potentiating osteogenic differentiation of human bone marrow mesenchymal stem cells via targeting ERα signaling

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2210-2227页

作者： Qing Zhao Junjie Feng Fubin Liu Qianxin Liang Manlin Xie jiaming Dong Yanfang Zou Jiali ye Guilong Liu Yue Cao Zhaodi Guo Hongzhi Qiao Lei Zheng Kewei Zhao Guangzhou Key Laboratory of Chinese Medicine Research on Prevention and Treatment of Osteoporosis the Third Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 510378China Guangdong Engineering Research Center of Chinese Herbal-derived Vesicles Guangzhou University of Chinese MedicineGuangzhou 510006China Department of Laboratory Medicine Nanfang HospitalSouthern Medical UniversityGuangzhou 510515China Guangdong Engineering and Technology Research Center for Rapid Diagnostic Biosensors Nanfang HospitalSouthern Medical UniversityGuangzhou 510515China The Fifth Affiliated Hospital Sun Yat-sen University Zhuhai 519000China Department of Blood Transfusion Guangdong Heyou International HospitalFoshan 528306China School of Pharmacy Nanjing University of Chinese MedicineNanjing 210023China

Although various anti-osteoporosis drugs are available,the limitations of these therapies,including drug resistance and collateral responses,require the development of novel anti-osteoporosis *** Drynariae displays a promising anti-osteoporosis effect,while the effective component and mechanism remain ***,we revealed the therapeutic potential of Rhizoma Drynariae-derived nanovesicles(RDNVs)for postmenopausal osteoporosis and demonstrated that RDNVs potentiated osteogenic differentiation of human bone marrow mesenchymal stem cells(hBMSCs)by targeting estrogen receptor-alpha(ERα).RDNVs,a natural product isolated from fresh Rhizoma Drynariae root juice by differential ultracentrifugation,exhibited potent bone tissue-targeting activity and anti-osteoporosis efficacy in an ovariectomized mouse ***,effectively internalized by hBMSCs,enhanced proliferation and ERαexpression levels of hBMSC,and promoted osteogenic differentiation and bone ***,via the ERαsignaling pathway,RDNVs facilitated mRNA and protein expression of bone morphogenetic protein 2 and runt-related transcription factor 2 in hBMSCs,which are involved in regulating osteogenic *** analysis revealed that naringin,existing in RDNVs,was the active component targeting ERαin the osteogenic *** together,our study identified that naringin in RDNVs displays exciting bone tissue-targeting activity to reverse osteoporosis by promoting hBMSCs proliferation and osteogenic differentiation through estrogen-like effects.

关键词： Rhizoma Drynariae-derived nanovesicles Bone marrow mesenchymal stem cells Bone targeting Osteogenic differentiation ERαsignaling Naringin Bone morphogenetic protein 2 Runt-related transcription factor 2

中风化、强风化泥质粉砂岩地层刀盘易结泥饼问题研究

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现代隧道技术 2022年第S2期59卷 239-244页

作者：叶家民扶亮张琪中铁二局第四工程有限公司成都610000

盾构在中风化、强风化泥质粉砂岩地层掘进中极易出现一些常见的施工问题,比如刀盘结泥饼、刀具磨损、盾构姿态难控制、管片上浮等。本文以长春地铁6号线蔚山路站—南四环路站—前进大街南站2个区间为案例,在施工过程中发现地层中蕴含裂... 详细信息

盾构在中风化、强风化泥质粉砂岩地层掘进中极易出现一些常见的施工问题,比如刀盘结泥饼、刀具磨损、盾构姿态难控制、管片上浮等。本文以长春地铁6号线蔚山路站—南四环路站—前进大街南站2个区间为案例,在施工过程中发现地层中蕴含裂隙水发育地段,刀盘易结泥饼,导致掘进速度缓慢。结合案例进行分析研究,讨论如何对结泥饼这一问题进行预防及处理,从而提高盾构施工的质量与效率,同时也为今后盾构施工提供一定的参考。

关键词：盾构中风化、强风化泥质粉砂岩刀盘泥饼