检索结果-南通市图书馆

基于磁性氧化石墨烯核酸适配体分离材料构建17β-雌二醇传感器

在线全文

学校读者我要写书评

暂无评论

色谱 2025年第1期43卷 87-95页

作者：金心宇陈乐源刘艳娜谢文菁彭汉勇中国科学院生态环境研究中心环境化学与生态毒理学国家重点实验室北京100085 中国科学院大学北京100049 中国科学院大学杭州高等研究院环境学院浙江杭州310024

17β-雌二醇(E2)是天然的甾体雌激素,在生物体的各项生理活动中发挥着至关重要的作用。然而,外源性E2也被归类为内分泌干扰物(EDC),即使在ng/L水平上也会干扰内分泌系统功能,且在医疗、畜牧业废水中均能检测到E2污染。目前,E2的检测方... 详细信息

17β-雌二醇(E2)是天然的甾体雌激素,在生物体的各项生理活动中发挥着至关重要的作用。然而,外源性E2也被归类为内分泌干扰物(EDC),即使在ng/L水平上也会干扰内分泌系统功能,且在医疗、畜牧业废水中均能检测到E2污染。目前,E2的检测方法主要以色谱-质谱联用方法为主,但受仪器等限制,难以应用于现场检测或大量样品检测。为了解决该难题,本工作用油包水微乳液法(W/O microemulsion)合成了一种基于磁性氧化石墨烯(MGO)的核酸分离材料,并进行了系统的表征,以开发高灵敏度、快速检测、高通量的荧光恢复(“turn-on”)型生物传感器,用于检测环境样品中的E2。传感器基于荧光共振能量转移原理(FRET),即MGO通过吸附荧光基团标记的E2核酸适配体发生FRET效应猝灭荧光信号,而在E2存在时,核酸适配体与E2结合,从MGO上脱附,实现荧光信号恢复,且信号响应与一定范围的E2质量浓度呈线性关系。本工作引入了磁性固相分离方法,降低了背景信号值,从而提高了方法的灵敏度。本方法中相对荧光恢复强度与E2质量浓度呈良好的线性关系,检出限低至1 ng/mL,对多种干扰离子有较好的抵抗性,且在同族雌激素类似物中有良好的选择性。与色谱-质谱检测方法相比,该方法检测时间短,成本低,操作简便,可应用于环境水样中E2的快速检测。

关键词： 17β-雌二醇磁固相分离荧光生物传感器磁性氧化石墨烯

Global asymptotic tracking of asymmetrical underactuated surface vessels with parameter uncertainties

在线全文

学校读者我要写书评

暂无评论

控制理论与应用（英文版） 2013年第4期11卷 608-614页

作者： wenjing xie Hailing SUN Baoli MA School of Automation Science and Electrical Engineering Beihang University

In this work, we investigate the tracking control problem of asymmetrical underactuated surface vessels with parameter uncertainties. The tracking error model is first derived via appropriate coordinate transformations, and is considered as a cascade structure composed of two subsystems. The Lyapunov redesign approach is employed to construct the control laws separately to stabilize the two subsystems with unknown model parameters. The cascade system theory is applied to prove the global uniform asymptotic convergence of the state trajectory to the reference one provided the desired yaw velocity is not vanishing. The effectiveness of the proposed control laws is verified by simulation examples.

关键词： Asymmetrical underactuated surface vessels Trajectory tracking Parameter uncertainties Lyapunovredesign

Average Consensus Control of Nonlinear Uncertain Multiagent Systems 36

在线全文

学校读者我要写书评

暂无评论

Average Consensus Control of Nonlinear Uncertain Multiagent ...

Mimicking peroxidase active site microenvironment by functionalized graphene quantum dots

第36届中国控制会议

作者： wenjing xie Baoli Ma School of Computer and Information Science Southwest University Department of Electrical Electronic and Computer EngineeringUniversity of Pretoria The Seventh Research Division School of Automation Science and Electrical EngineeringBeihang University

ISBN: (纸本)9781538629185

This paper investigates the average consensus control problem of a group of nonlinear uncertain systems.A novel distributed observer is presented to estimate the initial average state of the multiple nonlinear systems.A feedback controller is then constructed for each system to track the state of the observer,where the sliding-mode technology and the Lyapunov method are employed to address the difficulties caused by unknown individual nonlinear dynamics and bounded external *** combination of observer and sliding-mode technology releases the Lipschitz condition on nonlinear terms that is generally required in the published *** analysis shows that the states of all the nonlinear systems are globally asymptotically convergent to their initial average value,despite of the uncertain nonlinear dynamics with external *** results are obtained under the assumption that the communication graph is undirectional ***,a numerical simulation is provided to demonstrate the effectiveness of the proposed control law.

关键词： Nonlinear uncertain multiagent systems average consensus control distributed control distributed observer

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Nano Research 2020年第5期13卷 1427-1433页

作者： Qi Xin Xinrui Jia Asmat Nawaz wenjing xie Litao Li Jian Ru Gong CAS Center of Excellence for Nanoscience CAS Key Laboratory for Nanosystem&Hierarchical FabricationNational Center for Nanoscience and Technology11 Beiyitiao ZhongguancunBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Department of Orthopaedics the 309th Hospital of the PLABeijing 100091China

The development of high-efficiency peroxidase mimetics is highly desirable in view of high cost and low stability of natural *** the perspective of mimicking active site microenvironment at low cost,we herein report a novel histidine-functionalized graphene quantum dot(His-GQD)/hemin complex,which exhibits the highest catalytic rate for the peroxidase-based chromogenic reaction among the hemin-containing mimetics reported so ***,our peroxidase mimetic shows excellent tolerance to strongly acidic conditions and can function in a wide temperature ***-Burk plots and comprehensive electron paramagnetic resonance analysis reveal a ping-pong type catalytic mechanism for this *** addition,His-GQD/hemin demonstrates high efficiency and accuracy in detecting H2O2 and blood *** work provides an effective design of artificial enzymes for practical applications.

关键词： nanoenzyme graphene quantum dot heme active site peroxidase mimetic enzymatic microenvironment

Characterization,reactivity,source apportionment,and potential source areas of ambient volatile organic compounds in a typical tropical city

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2023年第1期123卷 417-429页

作者： Xiaocong Cao Qiao Xing Shanhu Hu Wenshuai Xu Rongfu xie Aidan Xian wenjing xie Zhaohui Yang Xiaochen Wu Hainan Research Academy of Environmental Sciences Haikou 571126China National Pilot Zone for Ecological Conservation(Hainan)Research Center Haikou 571126China

Based on one-year observation,the concentration,sources,and potential source areas of volatile organic compounds(VOCs)were comprehensively analyzed to investigate the pollution characteristics of ambient VOCs in Haikou,*** results showed that the annual average concentration of total VOCs(TVOCs)was 11.4 ppb V,and the composition was dominated by alkanes(8.2 ppb V,71.4%)and alkenes(1.3 ppb V,20.5%).The diurnal variation in the concentration of dominant VOC species showed a distinct bimodal distribution with peaks in the morning and *** greatest contribution to ozone formation potential(OFP)was made by alkenes(51.6%),followed by alkanes(27.2%).The concentrations of VOCs and nitrogen dioxide(NO_(2))in spring and summer were low,and it was difficult to generate high ozone(O_(3))concentrations through photochemical *** significant increase in O_(3)concentrations in autumn and winter was mainly related to the transmission of pollutants from the *** sources(40.1%),industrial sources(19.4%),combustion sources(18.6%),solvent usage sources(15.5%)and plant sources(6.4%)were identified as major sources of VOCs through the positive matrix factorization(PMF)*** southeastern coastal areas of China were identified as major potential source areas of VOCs through the potential source contribution function(PSCF)and concentration-weighted trajectory(CWT)***,the concentration of ambient VOCs in Haikou was strongly influenced by traffic sources and long-distance transport,and the control of VOCs emitted from vehicles should be strengthened to reduce the active species of ambient VOCs in Haikou,thereby reducing the generation of O_(3).

关键词： Volatile organic compounds(VOCs) Ozone Positive matrix factorization(PMF) model Backward trajectory Potential source area

Earnings Management of Chinese Listed Multinational Corporations

在线全文

学校读者我要写书评

暂无评论

China & World Economy 2023年第6期31卷 179-206页

作者： Xingyu Lu Tong Qi wenjing xie College of Business Shanghai University of Finance and EconomicsChina School of Economics and Management East China Normal UniversityChina School of Economics and Finance Shanghai International Studies UniversityChina

This study evaluates the quality of accounting information provided by Chinese multinational corporations(MNCs)in relation to the issue of earnings *** a combined dataset of outward foreign direct investment and financial statements by Chinese firms publicly listed on A-share markets between 2012 and 2017,we investigate whether Chinese MNCs are more inclined to manage *** discover that these firms exhibited significant earnings management behavior and typically adjusted their earnings *** demonstrate that these effects were more pronounced among private MNCs than state-owned firms,and in host countries with weaker institutional *** research reveals that after delaying the confirmation of current earnings,Chinese MNCs received higher government subsidies,and this pattern was particularly prevalent among private *** find no evidence that Chinese MNCs manipulated earnings to avoid paying taxes.

关键词： earnings management government subsidies multinational corporations outward foreign direct investment

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

自然湿地参与的大沽河流域水权交易模型

生态学杂志 2025年第2期44卷 673-683页

作者：谢文静郝成伟张俊龙陈明帅武可欣尤立孔范龙青岛大学环境科学与工程学院山东青岛266071 青岛市园林和林业综合服务中心山东青岛266061 中国科学院生态环境研究中心工业废水无害化与资源化国家工程研究中心北京100085

基于水权交易进行湿地配水是湿地生态需水保障的制度创新。本文基于区间两阶段随机双层不确定性规划方法构建水权交易模型,定量分析自然湿地参与交易机制对大沽河流域水资源系统的效应。结果表明:自然湿地参与交易机制减少了河段环境容... 详细信息

基于水权交易进行湿地配水是湿地生态需水保障的制度创新。本文基于区间两阶段随机双层不确定性规划方法构建水权交易模型,定量分析自然湿地参与交易机制对大沽河流域水资源系统的效应。结果表明:自然湿地参与交易机制减少了河段环境容量,限制了行业排污量及实际用水量;此外,该机制下自然湿地通过买入水权满足其需水量成为水权主要买方,提高了市场活力,而社会生产用户间水权交易量降低,种植业是生产用户中最主要的水权出让方;该机制考虑自然湿地的生态效益,随着植被覆盖率的提高,系统效益随之增大;基于多判据分析,自然湿地参与交易机制下75%植被覆盖率情景表现最优。研究结果可为自然湿地作为市场主体参与水权交易提供理论基础,为生态、生产用水协同优化配置提供决策支持。

关键词：生态需水保障自然湿地市场主体水权交易不确定性

Output Feedback Tracking Control of the Omni-Directional Robot Based on an Orientation Observer 36

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Output Feedback Tracking Control of the Omni-Directional Rob...

黑豆-乳清双蛋白对大鼠十二指肠屏障和肝损伤的保护作用

第36届中国控制会议

作者： Siyuan Li Yuxiang Guo Baoli Ma wenjing xie The Seventh Research Division School of Automation Science and Electrical EngineeringBeihang University School of Computer and Information Science Southwest University

ISBN: (纸本)9781538629185

In this paper,we study the output feedback tracking control problem of omni-directional ***,we construct an observer to estimate the value of unknown orientation of the robot through switching and event triggering *** to present works,the velocity of the robot is only required persistently exciting,and hence can go through zero,meanwhile,the acceleration measurement of the robot is ***,we design an output feedback tracking controller,guaranteeing that tracking errors asymptotically converge to ***,numerical simulations verify all obtained theoretical results.

关键词： Nonlinear Observer Output Feedback Control Omni-Directional Robot Nonlinear Control

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

食品工业科技 2025年第5期46卷 355-363页

作者：舒欣孟维洪谢文静张东杰王鹤霖富天昕庄柯瑾黑龙江八一农垦大学食品学院黑龙江大庆163319 国家杂粮工程技术研究中心黑龙江大庆163319 黑龙江省农产品加工与质量安全重点实验室黑龙江大庆163319

为了探究黑豆-乳清双蛋白(Black soybean-Whey blended Protein,B-WP)对大鼠十二指肠屏障损伤和肝损伤的保护作用机制,本研究选用低、中、高剂量B-WP喂食大鼠28 d,最后一天腹腔注射2.5 mg/kg脂多糖(Lipopolysaccharide,LPS)。采用酶联... 详细信息

为了探究黑豆-乳清双蛋白(Black soybean-Whey blended Protein,B-WP)对大鼠十二指肠屏障损伤和肝损伤的保护作用机制,本研究选用低、中、高剂量B-WP喂食大鼠28 d,最后一天腹腔注射2.5 mg/kg脂多糖(Lipopolysaccharide,LPS)。采用酶联免疫试剂盒检测十二指肠组织中的丙二醛(Malondialdehyde,MDA)、超氧化物歧化酶(Superoxide Dismutase,SOD)、谷胱甘肽(Glutathione,GSH)水平,Western Blot检测十二指肠中NF-κB p65、NF-κB p-p65、JAK2和STAT3的蛋白表达水平,并通过HE染色、酶联免疫法和实时荧光定量PCR对检测肝脏的组织形态、谷丙转氨酶(Alanine Aminotransferase,ALT)和谷草转氨酶(Aspartate Aminotransferase,AST)含量以及Toll样受体4(Toll-like Receptor 4,TLR4)、髓样分化因子88(Myeloid Differentiation Primary Response protein 88,MyD88)基因mRNA表达进行分析。结果表明:LPS会引起十二指肠氧化应激,激活NF-κB/JAK2/STAT3通路和肝损伤,进而造成十二指肠屏障损伤;低、中、高剂量B-WP膳食干预均能够调节氧化应激,其中中剂量膳食干预效果最为显著(P<0.01),具体表现为MDA含量减少34.93%,SOD活力提高61.16%,GSH含量增加48.48%;不同剂量B-WP膳食干预均能够下调NF-κB p65、NF-κB p-p65、JAK2和STAT3的蛋白含量,中剂量膳食干预效果最好,使NF-κB p65、NF-κB p-p65、JAK2和STAT3蛋白含量显著降低35.06%、42.53%、45.88%和44.32%(P<0.01);不同剂量的B-WP膳食对肝损伤程度均有所改善,以中剂量膳食干预效果最为显著(P<0.01),使ALT和AST水平分别降低47.07%和41.79%,TLR4和MyD88的mRNA含量分别降低48.87%和45.46%。综合来看,B-WP对LPS诱导的十二指肠屏障损伤的保护作用可能是通过调节氧化应激、抑制NF-κB/JAK2/STAT3通路的活化和改善肝损伤来实现,并且中剂量B-WP膳食的保护效果最佳。

关键词：黑豆-乳清蛋白十二指肠屏障氧化应激 NF-κB/JAK2/STAT3 通路肝脏