检索结果-南通市图书馆

基于自适应滑模观测器的无传感器PMSM系统设计

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

机电工程技术 2024年第7期53卷 163-166页

作者：周玉莹罗静戴鑫曾云峰黄鑫荆楚理工学院电子信息工程学院湖北荆门448000 长江大学电气工程学院湖北荆州434023

为解决传统自适应滑模观测器存在跟踪精度较低、抖振较大等问题,在传统滑膜观测器的基础上,提出了一种改进的幂指数趋近律,使系统更加平稳地趋近滑模面,并证明了该趋近律的存在性、合理性。首先,建立了永磁同步电机的数学模型;其次,根... 详细信息

为解决传统自适应滑模观测器存在跟踪精度较低、抖振较大等问题,在传统滑膜观测器的基础上,提出了一种改进的幂指数趋近律,使系统更加平稳地趋近滑模面,并证明了该趋近律的存在性、合理性。首先,建立了永磁同步电机的数学模型;其次,根据电流的状态方程和滑模的等效控制理论,估计出PMSM在两相静止坐标系下的反电动势,并由此得到在传统滑模观测器转子位置;再次,基于改进的幂指数趋近律,设计了新的转子位置观测器,并利用Lyapunov稳定性理论证明了观测器的稳定性;最后,在MATLAB平台上进行了仿真,以幂指数趋近律构建转子位置,搭建Simulink仿真模型,将传统滑模趋近律与幂指数趋近律进行了对比分析,结果表明,改进的幂指数观测器能够有效地降低转子位置跟踪过程中的抖振,并提高跟踪精度。

关键词：滑模观测器永磁同步电机趋近律

基于UPLC-Q-TOF-MS法分析陈皮中的化学成分

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

中国调味品 2024年第4期49卷 166-172页

作者：黄晓媛李焱鑫董浩赵文红白卫东钱敏毕思远仲恺农业工程学院轻工与食品科学学院广州510225 仲恺农业工程学院广东省岭南特色食品科学与技术重点实验室农业农村部岭南特色食品绿色加工与智能制造重点实验室现代农业工程创新研究院广州510225 深圳市金阅检测科技有限责任公司广东深圳518120

利用超高效液相色谱-四极杆-飞行时间质谱法(UPLC-Q-TOF-MS)结合数据分析平台在线分析陈皮中71种化学成分,包括黄酮类、生物碱、香豆素和脂类等9类。通过主成分分析(PCA)及正交偏最小二乘判别分析(OPLS-DA)发现不同陈化年份陈皮中的化... 详细信息

利用超高效液相色谱-四极杆-飞行时间质谱法(UPLC-Q-TOF-MS)结合数据分析平台在线分析陈皮中71种化学成分,包括黄酮类、生物碱、香豆素和脂类等9类。通过主成分分析(PCA)及正交偏最小二乘判别分析(OPLS-DA)发现不同陈化年份陈皮中的化学成分具有明显差异,并筛选出17种特征性成分,随着陈化年份的延长,异甘草苷、山奈酚-3-O-β-D-槐糖苷、百蕊草素Ⅰ含量增加,脱水红花黄色素B、补骨脂查尔酮含量减少。此方法可用于区分陈化3,5,10,15,20年的陈皮。该研究了解了陈皮中化学组成并阐明了不同陈化年份陈皮间化学成分存在的差异,对合理开发陈皮的食用和药用价值具有指导意义,为不同陈化年份陈皮的鉴别提供了科学依据。

关键词：陈皮化学成分 UPLC-Q-TOF-MS 黄酮类物质

yy 1885—2023《传染病患者运送负压隔离舱》标准解析

在线全文

学校读者我要写书评

暂无评论

医疗卫生装备 2024年第8期45卷 12-15页

作者：刘克洋黄永富胡广勇北京市医疗器械检验研究院(北京市医用生物防护装备检验研究中心) 北京101111

介绍了yy 1885—2023《传染病患者运送负压隔离舱》的制定背景,从术语定义、适用范围及性能要求3个方面对标准进行了解析,为正确理解标准条款和产品研发、生产、检验等环节提供了参考。

关键词： yy 1885—2023 负压隔离舱传染病生物防护生物防护装备标准解析

yy 1887—2023《医用正压防护服》标准解析

在线全文

学校读者我要写书评

暂无评论

医疗卫生装备 2024年第8期45卷 7-11页

作者：刘克洋黄永富胡广勇北京市医疗器械检验研究院(北京市医用生物防护装备检验研究中心) 北京101111

介绍了yy 1887—2023《医用正压防护服》的制定背景和制定过程中参考的国内外标准,从适用范围、结构组成及主要性能要求3个方面对标准进行了解析,为正确理解标准条款和产品研发、生产、检验等环节提供了参考。

关键词： yy 1887—2023 正压防护服生物防护医用个体防护装备标准解析

Propionate stimulates the secretion of satiety hormones and reduces acute appetite in a cecal fistula pig model

在线全文

学校读者我要写书评

暂无评论

Animal Nutrition 2022年第3期10卷 390-398页

作者： Yanan Zhang Xuan Li Guowen huang Haifeng Wang Huizi Chen Yong Su Kaifan Yu Weiyun Zhu Laboratory of Gastrointestinal Microbiology Jiangsu Key Laboratory of Gastrointestinal Nutrition and Animal HealthCollege of Animal Science and TechnologyNanjing Agricultural UniversityNanjing210095China National Center for International Research on Animal Gut Nutrition Nanjing Agricultural UniversityNanjing210095China Changjia(Shanghai)Agricultural Technology Co. Ltd.Shanghai201414China

Short-chain fatty acids(SCFA)can regulate appetite by stimulating the secretion of satiety ***,the impact of short-chain fatty acid propionate on the release of gut satiety hormones and appetite regulation in pigs is not completely *** this study,16 pigs were infused with saline or sodium propionate through a fistula in the caecum during a 28-day experimental *** characterized the effects of propionate administration on peptide yy(Pyy)and glucagon-like peptide 1(GLP-1)secretion from colonic tissue,and investigated the role of propionate infusion on the expression of appetite-related genes in the colon and ***,the direct impact of propionate administration on the expression of orexigenic neuropeptide agouti-related protein(AgRP)in hypothalamic N38 cells was also *** results showed that intra-cecal infusion of propionate reduced the short-term feed intake(P0.05).Propionate administration stimulated Pyy and GLP-1 release from colon tissue in vivo and ex vivo(Pyy expression in the colonic mucosa(Pyy levels in the blood were increased after intra-cecal infusion of propionate at d 28(P<0.05).Additionally,intra-cecal infusion of propionate upregulated the mRNA and protein expression of free fatty acid receptor 2/3(FFAR2/FFAR3)in the colonic mucosa(P<0.05).Propionate infusion also downregulated the orexigenic AgRP mRNA expression(P<0.05)and upregulated the anorexigenic cocaine-and amphetamine-regulated transcript(CART)mRNA expression(P=0.09)in the ***,propionate administration directly downregulated AgRP expression in hypothalamic N38 cells in a dose-dependent manner(P<0.05).Collectively,these findings demonstrated that cecal propionate stimulated colonic secretion of satiety hormones and suppressed appetite to reduce the short-term feed intake in *** study highlights that microbial-deriv

关键词： Propionate Gut hormones Appetite Hypothalamus Pig

Architectural Design and Additive Manufacturing of Mechanical Metamaterials:A Review

在线全文

学校读者我要写书评

暂无评论

Engineering 2022年第10期17卷 44-63页

作者： Chenxi Lu Mengting Hsieh Zhifeng huang Chi Zhang Yaojun Lin Qiang Shen Fei Chen Lianmeng Zhang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Department of Mechanical and Aerospace Engineering University of CaliforniaIrvineCA 90095USA

Mechanical metamaterials can be defined as a class of architected materials that exhibit unprecedented mechanical properties derived from designed artificial architectures rather than their constituent *** macroscale and simple layouts can be realized by conventional top-down manufacturing approaches,many of the sophisticated designs at various length scales remain elusive,due to the lack of adequate manufacturing *** progress in additive manufacturing(AM)has led to the realization of a myriad of novel metamaterial *** methods capable of fabricating microscale architectures with high resolution,arbitrary complexity,and high feature fidelity have enabled the rapid development of architected meta materials and drastically reduced the design-computation and experimental-validation *** paper first provides a detailed review of various topologies based on the desired mechanical properties,including stiff,strong,and auxetic(negative Poisson’s ratio)metamaterials,followed by a discussion of the AM technologies capable of fabricating these ***,we discuss current challenges and recommend future directions for AM and mechanical metamaterials.

关键词： Mechanical metamaterials Auxetic materials Architectural design Additive manufacturing

Combined toxicity of copper and cadmium to six rice genotypes (Oryza sativa L.)

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2009年第5期21卷 647-653页

作者： huang Yizong, HU Ying, LIU Yunxia Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Accumulations of copper （Cu） and cadmium （Cd） in six rice cultivars （94D-22, 94D-54, 94D-64, Gui630, yy-1, and KY1360） were evaluated through exposure to heavy metal contamination （100 mg/kg Cu, 1.0 mg/kg Cd, and 100 mg/kg Cu ＋ 1.0 mg/kg Cd） in a greenhouse. The dry weights of shoot and root, concentrations of Cu and Cd in plant tissues and the Cu, Cd, P, Fe concentrations in the root surface iron plaques were analyzed eight weeks later after treatment. The results indicated that the plant biomass was mainly determined by rice genotypes, not Cu and Cd content in soil. Separated treatment with Cu/Cd increased each metal level in shoot, root and iron plaques. Soil Cu enhanced Cd accumulation in tissues. In contrast, Cu concentrations in shoot and root was unaffected by soil Cd. Compared to single metal contamination, combined treatment increased Cd content by 110.6%, 77.0%, and 45.2% in shoot, and by 112.7%, 51.2% and 18.4% in root for Gui630, yy-1, and KY1360, respectively. The content level of Cu or Cd in root surface iron plaques was not affected by their soil content. Cu promoted Fe accumulation in iron plaques, while Cd has no effect on P and Fe accumulation in it. The translocation of Cu and Cd from iron plaques to root and shoot was also discussed. These results might be beneficial in selecting cultivars with low heavy metal accumulation and designing strategies for soil bioremediation.

关键词： Cu Cd combined contamination soil uptake accumulation root surface iron plaques

Pharmacometabolomic prediction of individual differences of gastrointestinal toxicity complicating myelosuppression in rats induced by irinotecan

在线全文

学校读者我要写书评

暂无评论

Acta Pharmaceutica Sinica B 2019年第1期9卷 157-166页

作者： Yiqiao Gao Wei Li Jiaqing Chen Xu Wang Yingtong Lv Yin huang Zunjian Zhang Fengguo Xu Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education) State Key Laboratory of Natural MedicineChina Pharmaceutical University Jiangsu Key Laboratory of Drug Screening China Pharmaceutical University

Pharmacometabolomics has been already successfully used in toxicity prediction for one specific adverse effect. However in clinical practice, two or more different toxicities are always accompanied with each other, which puts forward new challenges for pharmacometabolomics. Gastrointestinal toxicity and myelosuppression are two major adverse effects induced by Irinotecan(CPT-11),and often show large individual differences. In the current study, a pharmacometabolomic study was performed to screen the exclusive biomarkers in predose serums which could predict late-onset diarrhea and myelosuppression of CPT-11 simultaneously. The severity and sensitivity differences in gastrointestinal toxicity and myelosuppression were judged by delayed-onset diarrhea symptoms, histopathology examination, relative cytokines and blood cell counts. Mass spectrometry-based non-targeted and targeted metabolomics were conducted in sequence to dissect metabolite signatures in predose serums. Eventually,two groups of metabolites were screened out as predictors for individual differences in late-onset diarrhea and myelosuppression using binary logistic regression, respectively. This result was compared with existing predictors and validated by another independent external validation set. Our study indicates the prediction of toxicity could be possible upon predose metabolic profile. Pharmacometabolomics can be a potentially useful tool for complicating toxicity prediction. Our findings also provide a new insight into CPT-11 precision medicine.

关键词： Irinotecan Individual differences Complicating toxicity Prediction Metabolomics Gastrointestinal toxicity Biomarkers Diarrhea

Trends in mortality of emergency departments patients in China

在线全文

学校读者我要写书评

暂无评论

World Journal of Emergency Medicine 2019年第3期10卷 152-155页

作者： Chang Pan Xiao-ran huang Jiao-jiao Pang Kai Cheng Feng Xu Yu-guo Chen Department of Emergency Medicine and Chest Pain Center Qilu Hospital of Shandong University Jinan China Clinical Research Center for Emergency and Critical Care Medicine of Shandong Province Institute of Emergency and Critical Care Medicine of Shandong University Qilu Hospital of Shandong University Jinan China Key Laboratory of Emergency and Critical Care Medicine of Shandong Province Key Laboratory of Cardiopulmonary-Cerebral Resuscitation Research of Shandong Province Qilu Hospital of Shandong University Jinan China The Key Laboratory of Cardiovascular Remodeling and Function Research Chinese Ministry of Education Chinese Ministry of Health and Chinese Academy of Medical SciencesThe State and Shandong Province Joint Key Laboratory of Translational Cardiovascular MedicineQilu Hospital of Shandong University Jinan China Department of Emergency Medicine Department of Emergency and Critical Care Medicine Guangdong Provincial People's Hospital Guangdong Academy of Medical Sciences Guangzhou China Medical College Shantou University Shantou China

BACKGROUND: Emergency medical service system (EMSS) in China is becoming more important. However, studies on mortality of emergency departments (EDs) patients in tertiary hospitals and on the trends in mortality of ED patients all over China are stagnant. The objective of this study was to quantify and describe the trends in mortality of ED patients in China. METHODS: Nine tertiary teaching hospitals were selected from tertiary teaching hospitals in different regions. The annual numbers of ED visits and deaths of these hospitals in 2004, 2009 and 2014 were recorded and analyzed. Chi-square test was used to compare the mortality of the EDs’ visits. Moreover, data on the mortality of ED patients in China from 2005 to 2015 were summarized and analyzed from the China Health and Family Planning Statistical Yearbooks (2006–2016). RESULTS: From 2004 to 2014, the overall annual mortalities in EDs increased among the tertiary hospitals (P<0.001). However, the overall annual mortality in EDs all over China decreased from 0.12% in 2005 to 0.08% in 2015. And the mortalities of EDs patients in the eastern, central and western regions of China all decreased. In addition, the average mortality of EDs patients in northern China was obviously higher than that in southern China (P<0.05). CONCLUSION: The ED mortality was increased in tertiary hospitals while decreased all over China during the past decade, which may be partly caused by some critical challenges faced by China’s EMSS, such as overcrowding and long length of stay in EDs of tertiary hospitals.

关键词： Mortality Emergency departments Tertiary hospitals Trends