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基于UPLC-Q-TOF-MS的连翘不同部位成分分析及其抗炎活性评价

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中国中药杂志 2024年第4期49卷 968-980页

作者：牟越刘博张璇张烨蔚杰王晓晴陈育伍崔晓兰潘英妮孙奕沈阳药科大学中药学院辽宁沈阳110016 中国中医科学院中药研究所北京100700 岳康药业集团有限公司山西临汾042500

基于超高效液相色谱-串联四极杆飞行时间质谱(UPLC-Q-TOF-MS)技术结合自建化学成分数据库,对连翘Forsythia suspensa的叶、花、果实、青翘、老翘、种子等11个部位中化学成分进行整体表征和鉴定。运用主成分分析、偏最小二乘法判别分析... 详细信息

基于超高效液相色谱-串联四极杆飞行时间质谱(UPLC-Q-TOF-MS)技术结合自建化学成分数据库,对连翘Forsythia suspensa的叶、花、果实、青翘、老翘、种子等11个部位中化学成分进行整体表征和鉴定。运用主成分分析、偏最小二乘法判别分析等化学计量学方法,评价连翘不同部位的质量属性与差异。从连翘中共推测鉴定出79个化合物,包括13个苯乙醇苷类、10个木脂素类、12个黄酮类、10个有机酸类、14个萜类及20个其他类型化合物。其中,34个化合物为连翘不同部位间差异的主要变量,且连翘叶和青翘中各成分的相对含量较高。应用脂多糖(LPS)诱导的RAW264.7细胞炎症模型,评价了连翘不同部位提取物及主要成分的抗炎活性。结果显示,青翘、连翘花、连翘枝和连翘梗的提取物均具有一定的抗炎活性,且连翘酯苷A、连翘苷、连翘脂素、(+)-松脂素-β-D-吡喃葡萄糖苷等成分也具有可显著抑制NO释放的抗炎活性。该研究对连翘不同部位的化学成分进行了较全面的分析以及抗炎活性评价,为连翘的资源开发和综合利用提供参考。

关键词：连翘不同药用部位成分分析质量评价抗炎活性

Synthetic Two-dimensional Organic Structures

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Chinese Journal of Polymer Science 2018年第4期36卷 425-425,426-444页

作者： Hui Liu Xiao-Nan Kan chen-yu wu Qing-Yan Pan Zhi-Bo Li Ying-Jie Zhao Qingdao University of Science and Technology Qingdao 266042China Centre for Advanced Macromolecular Design School of Chemical EngineeringThe University of New South WalesSydneyNSW2052Australia

Synthetic two-dimensional（2 D） polymers have totally different topology structures compared with traditional linear or branched polymers. The peculiar 2 D structures bring superior properties. Although, from linear to 2 D polymers, the study of these new materials is still in its infancy, they already show potential applications especially in optoelectronics, membranes, energy storage and catalysis, etc. In this review, we summarize the recent progress of the 2 D materials from three respects：（1） Chemistry—different types of polymerization reactions or supramolecular assembly to construct the 2 D networks were described;（2） Preparation methods—surface science, crystal engineering approaches and solution synthesis were introduced;（3） Functionalization and some early applications.

关键词： Two-dimensional structures Interracial synthesis 2D crystal Covalent organic frameworks (COFs) Supramolecular assembly

Cosmological interpretation for the stochastic signal in pulsar timing arrays

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 43-50页

作者： yu-Mei wu Zu-cheng chen Qing-Guo Huang School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Astronomy Beijing Normal UniversityBeijing 100875China Advanced Institute of Natural Sciences Beijing Normal UniversityZhuhai 519087China Department of Physics and Synergistic Innovation Center for Quantum Effects and Applications Hunan Normal UniversityChangsha 410081China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

The pulsar timing array(PTA)collaborations have recently reported compelling evidence for a stochastic signal consistent with a gravitational-wave *** this paper,we combine the latest data sets from NANOGrav,PPTA,and EPTA to explore cosmological interpretations for the PTA signal from first-order phase transitions,domain walls,and cosmic strings,*** find that the domain wall model is strongly disfavored with the Bayes factors compared with the first-order phase transitions and cosmic strings being 1/90 and 1/189,respectively,breaking the degeneracy among these models in individual data *** also find that:(1)a strong phase transition at temperatures below the electroweak scale is favored,and the bubble collisions make the dominant contribution to the energy density spectrum;(2)a small reconnection probability p<1.55×10^(-1)allowed by strings in(super)string theory is favored at the 95%confidence level,and ground-based detectors can further constrain the parameter space.

关键词： puslar timing arrays gravitational-wave background first-order phase transitions domain walls cosmic strings

Engineering particles towards 3D supraballs-based passive cooling via grafting CDs onto colloidal photonic crystals

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Chinese Chemical Letters 2024年第4期35卷 457-463页

作者： Jie wu Xiaoqing yu Guoxing Li Su chen State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 210009China

Particle engineering has opened the floodgates to material science in both fundamental and application field. However, covalent interactions have not yet been adequately designed in the particle engineering for functional colloidal photonic crystals(CPCs). Herein, we achieved covalent coupling between carboxylrich poly(styrene-acrylic acid)(P(St-AA)) monodispersed colloidal particles and amine-rich carbon dots(CDs) based on an feasible and universal particle engineering strategy. The designed CDs-grafted P(St-AA)monodispersed colloidal particles initiate a hydrogen bond-driven assembly mode and ensure the construction of large-scale crack-free CPCs. Moreover, the CDs equipped with selective broad-band absorption capacity could improve the saturation of structural colors for high-visibility CPCs. Furthermore, an injectable photonic hydrogel(IPH) is developed to design CPC supraball hydrogel via integrating the CDsgrafted P(St-AA) CPC supraballs with supramolecular hydrogel. Combining superior flexibility, sufficient self-healing capacity of supramolecular hydrogel with visual optical information of our CPC supraballs, a cyclically reversible coding and decoding system was developed. Meanwhile, we firstly demonstrated the novel strategy of 3D supraballs-based passive cooling. The designed 3D CPC supraball hydrogel presents nearly full observation angle reflections behavior and excellent water evaporation capacity and achieves3.6 ℃ temperature drops, showing the application advantages in 3D thermal management. This work not only provides a new insight for manipulating optical properties of CPCs, but also demonstrates an easyto-perform platform, as well as indicates the direction for the promising application of CPCs.

关键词： Particle engineering Carbon dots Colloidal photonic crystals Passive cooling Digital coding

Pd-catalyzed intermolecular Si–O formation via Si–C activation

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Science China Chemistry 2024年第8期67卷 2661-2669页

作者： Shuang Liu yu-Shu chen Yichen wu Peng Wang State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesShanghai 200032China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China College of Material Chemistry and Chemical Engineering Key Laboratory of Organosilicon Chemistryand Material Technology of Ministry of EducationHangzhou Normal UniversityHangzhou 311121China

The development of efficient Si–O bond formation reaction with 100% atom-economy, excellent functional group tolerance, and broad scope under mild conditions is highly desired due to the prevalence of silanol, silyl ether, and their derivatives in synthetic chemistry and materials science. Here, we have realized the Pd-catalyzed Si–O formation reaction via a Si–C activation approach with 100% atom-economy by employing silacyclobutanes(SCBs) and various hydroxy-containing substrates, including water,alcohols, phenols, and silanols. This protocol features a broad substrate scope, remarkable functional compatibility and mild conditions, providing a series of silanols, silyl ethers in high efficiency. Notably, this protocol could also be used for selective protection of hydroxy functionalities, and for the access of a class of novel polymers containing Si–O main chain. Preliminary mechanistic studies unveiled that this reaction underwent a Pd-catalyzed concerted ring-opening mechanism.

关键词： Si–O formation Si–C activation palladium silacyclobutane silanol silyl ether

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Expression of PIN Genes in Rice （Oryza sativa L.）： Tissue Specificity and Regulation by Hormones

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Molecular Plant 2009年第4期2卷 823-831页

作者： Ji-Rong Wang Han Hu Gao-Hang Wang Jing Li Jie-yu chen Ping wu State Key Laboratory of Plant Physiology and Biochemistry College of Life Sciences Zi Jin Gang Campus Zhejiang University Hangzhou 310058 People's Republic of China

Twelve genes of the PIN family in rice were analyzed for gene and protein structures and an evolutionary relationship with reported AtPINs in Arabidopsis. Four members of PIN1 （designated as OsPINla-d）, one gene paired with AtPIN2 （OsPIN2）, three members of PIN5 （OsPIN5a-c）, one gene paired with AtPIN8 （OsPIN8）, and three monocot-specific PINs （OsPIN9, OsPINIOa, and b） were identified from the phylogenetic analysis. Tissue-specific expression patterns of nine PIN genes among them were investigated using RT-PCR and GUS reporter. The wide variations in the expression domain in different tissues of the PIN genes were observed. In general, PIN genes are up-regulated by exogenous auxin, while different responses of different PIN genes to other hormones were found.

关键词： Oryza sativa L. PIN family expression pattern.

Stochastic Flexibility Evaluation for Virtual Power Plants by Aggregating Distributed Energy Resources

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 988-999页

作者： Siyuan Wang Wenchuan wu Qizhan chen Junjie yu Peng Wang Department of Electrical Engineering Tsinghua UniversityBeijing 100084China Zhongshan Power Supply Bureau of the Guangdong Power Grid Corporation Zhongshan 528400China Beijing Qingda Gaoke System Control Company Beijing 102208China CSEE IEEE

To manage a large amount of flexible distributed energy resources(DERs)in the distribution networks,the virtual power plant(VPP)is introduced into the *** VPP can optimally dispatch these resources in a cluster manner and provide flexibility for the power system operation as a *** existing studies formulate the equivalent power flexibility of the aggregating DERs as deterministic optimization models without considering their *** this paper,we introduce the stochastic power flexibility range(PFR)and timecoupling flexibility(TCF)to describe the power flexibility of *** this model,both operational constraints and the randomness of the DERs’output are incorporated,and a combined model and data-driven solution is proposed to obtain the stochastic PFR,TCF,and cost function of *** aggregating model can be easily incorporated into the optimization model for the power system operator or market bidding,considering ***,a numerical test is *** results show that the proposed model not only has higher computational efficiency than the scenario-based methods but also achieves more economic benefits.

关键词： Chance constrained optimization combined model and data-driven stochastic power flexibility virtual power plant

Numerical modeling of all-day albedo variation for bifacial PV systems on rooftops and annual yield prediction in Beijing

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Building Simulation 2024年第6期17卷 955-964页

作者： Xiaoxiao Su chenglong Luo Xinzhu chen Jie Ji Yanshun yu yuandan wu wu Zou School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing210094China Department of Thermal Science and Energy Engineering University of Science and Technology of ChinaHefei230027China Institute of Energy Research Jiangxi Academy of SciencesNanchang330096China

Bifacial PV modules capture solar radiation from both sides,enhancing power generation by utilizing reflected ***,there are difficulties in obtaining ground albedo data due to its dynamic *** address this issue,this study established an experimental testing system on a rooftop and developed a model to analyze dynamic albedo variations,utilizing specific data from the *** results showed that the all-day dynamic variations in ground albedo ranged from 0.15 to 0.22 with an average of ***,this study evaluates the annual performance of a bifacial PV system in Beijing by considering the experimental conditions,utilizing bifacial modules with a front-side efficiency of 21.23%and a bifaciality factor of 0.8,and analyzing the dynamic all-day albedo data obtained from the numerical *** results indicate that the annual radiation on the rear side of bifacial PV modules is 278.90 kWh/m^(2),which accounts for only 15.50%of the front-side ***,when using the commonly default albedo value of 0.2,the rear-side radiation is 333.01 kWh/m^(2),resulting in an overestimation of 19.40%.Under dynamic albedo conditions,the bifacial system is predicted to generate an annual power output of 412.55 kWh/m^(2),representing a significant increase of approximately 12.37%compared to an idealized monofacial PV system with equivalent front-side *** a 25-year lifespan,the bifacial PV system is estimated to reduce carbon emissions by 8393.91 kgCO_(2)/m^(2),providing an additional reduction of 924.31 kgCO_(2)/m^(2)compared to the idealized monofacial PV *** findings offer valuable insights to promote the application of bifacial PV modules.

关键词： bifacial PV module ground albedo simulation carbon emission reduction

Dissipation-Driven Superradiant Phase Transition of a Two-Dimensional Bose-Einstein Condensate in a Double Cavity

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Chinese Physics Letters 2024年第6期41卷 44-48页

作者： Bo-Hao wu Xin-Xin Yang yu chen Wei Zhang Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices Renmin University of ChinaBeijing 100872China Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education) Renmin University of ChinaBeijing 100872China Graduate School of China Academy of Engineering Physics Beijing 100193China Beijing Academy of Quantum Information Sciences Beijing 100193China

We study superradiant phase transitions in a hybrid system of a two-dimensional Bose–Einstein condensate of atoms and two cavities arranged with a tilt *** adjusting the loss rate of cavities,we map out the phase diagram of steady states within a mean field *** is found that when the loss rates of the two cavities are different,superradiant transitions may not occur at the same time in the two cavities.A first-order phase transition is observed between the states with only one cavity in superradiance and both in *** the case that both cavities are superradiant,a net photon current is observed flowing from the cavity with small decay rate to the one with large decay *** photon current shows a non-monotonic dependence on the loss rate difference,owing to the competition of photon number difference and cavity field phase *** findings can be realized and detected in experiments.

关键词： Einstein transitions decay