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Characterization of molecular signature of the roots of Paeonia lactiflora during growth

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Chinese Journal of Natural Medicines 2017年第10期15卷 785-793页

作者： LIU Pei XU Yuan YAN Hui CHEN Jing shang er-xin QIAN Da-Wei JIANG Shu DUAN Jin-Ao Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization and National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine Nanjing University of Chinese MedicineNanjing 210023China Institute of Bioengineering Zhejiang Chinese Medical UniversityHangzhou 310053China

The roots of Paeoniae lactiflora *** widely consumed as crude drugs in Asian countries due to their remarkable beneficial health *** present research was undertaken to illuminate the dynamic changes in metabolites and enzymes and facilitate selection of the harvesting time when the herb can provide optimum health *** roots were analyzed at 12 stages of growth for monoterpenoid glycosides,phenols,nucleosides,nucleobases,amino acids,and polysaccharides by high-performance liquid chromatography with photodiode array detector,ultra-high pressure liquid chromatography coupled with tandem mass spectrometry,and UV *** enzyme activities of plant β-glucosidases and esterases were determined by UV *** total content of monoterpenoid glycosides and phenols peaked in *** nucleosides and nucleobases,the highest content appeared in *** maximum phasic accumulation of the total amino acids took place in March,and the content of total polysaccharides reached a peak value in ***,April,and March were selected as the appropriate harvesting times for producing natural medicinal or health food *** β-glucosidases and esterases showed the highest activity in December and May,*** the activity of β-glucosidase increased,esterase activity decreased,while the contents of oxypaeoniflora and paeoniflorin *** esterase activity increased,the contents of benzoylpaeoniflorin,paeoniflorin,and gallic acid *** conclusion,the results from the present study would be useful in determination of the suitable time for harvesting *** roots for medicinal purposes.

关键词： Paeonia lactiflora Primary and secondary metabolites Plant enzymes Dynamic change Growth stage

Two new nonacosanetriols from the pollen of Typha angustifolia

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Chinese Chemical Letters 2010年第2期21卷 209-212页

作者： Tao, Wei Wei Yang, Nian Yun Duan, Jin Ao Wu, De Kang shang, er xin Qian, Da Wei Tang, Yu Ping Nanjing Univ Chinese Med Jiangsu Key Lab TCM Formuale Res Nanjing 210046 Peoples R China

Chemical investigation of the pollen of Typha angustifolia *** led to the isolation of two new nonacosanetriols,7,8,10- nonacosanetriol(1) and 7,9,10-nonacosanetriol(2).Their structures were elucidated by chemical rea... 详细信息

关键词： Typha angustifolia Nonacosanetriol Antiplatelet aggregation

Health diagnosis of ultrahigh arch dam performance using heterogeneous spatial panel vector model

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Water Science and Engineering 2024年第2期17卷 177-186页

作者： er-feng Zhao xin Li Chong-shi Gu The National Key Laboratory of Water Disaster Prevention Hohai UniversityNanjing 210098China NationalEngineering Research Centerof Water Resources Eficient Utilization and Engineering Safety Hohai UniversityNanjing 20098China

Currently,more than ten ultrahigh arch dams have been constructed or are being constructed in *** control is essential to long-term operation of these *** study employed the flexibility coefficient and plastic complementary energy norm to assess the structural safety of arch dams.A comprehensive analysis was conducted,focusing on differences among conventional methods in characterizing the structural behavior of the Xiaowan arch dam in ***,the spatiotemporal characteristics of the measured performance of the Xiaowan dam were explored,including periodicity,convergence,and time-effect *** findings revealed the governing mechanism of main ***,a heterogeneous spatial panel vector model was developed,considering both common factors and specific factors affecting the safety and performance of arch *** model aims to comprehensively illustrate spatial heterogeneity between the entire structure and local regions,introducing a specific effect quantity to characterize local deformation ***,the proposed model was applied to the Xiaowan arch dam,accurately quantifying the spatiotemporal heterogeneity of dam ***,the spatiotemporal distri-bution characteristics of environmental load effects on different parts of the dam were reasonably *** of the model prediction enhances its credibility,leading to the formulation of health diagnosis criteria for future long-term operation of the Xiaowan *** findings not only enhance the predictive ability and timely control of ultrahigh arch dams'performance but also provide a crucial basis for assessing the effectiveness of engineering treatment measures.

关键词： Ultrahigh arch dam Structural performance Deformation behavior Diagnosis criterion Panel data model

Freestanding MoSe_(2)nanoflowers for superior Li/Na storage properties

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Tungsten 2024年第1期6卷 238-247页

作者： Qiao Cu Chao-Qun shang Guo-Fu Zhou xin Wang Guangdong Provincial Key Laboratory of Optical Information Materials South China Normal UniversityGuangzhou 510006China School of Materials Science and Engineering and Hubei Key Laboratory of Plasma Chemistry and Advanced Materials Wuhan Institute of TechnologyWuhan 430205China International Academy of Optoelectronics at Zhaoqing South China Normal UniversityZhaoqing 526060China

MoSe_(2),with high theoretical specific capacity,has attracted a lot of *** remains an open challenge to effectively suppress the irreversible selenium dissolution and rapid capacity decrease induced by severe volume change during ***,we synthesize MoSe_(2)nanoflowers dispersed on one-dimensional(1D)N-doped carbon nanofibers(MoSe_(2)@NCNFs)for use as a freestanding *** this unique structure,the 1D N-doped carbon nanofibers are found to not only enhance the conductivity but also ensure the structural integrity during the Li^(+)/Na^(+)insertion/destraction *** expected,at 2 A·g^(-1),the specific capacity of the MoSe_(2)@NCNFs is maintained at 180 mAh·g^(-1)after 500 cycles when used in lithium storage ***,in the case of sodium storage,at 1 A·g^(-1),the MoSe_(2)@NCNFs shows a capacity of 122mAh·g^(-1)after 500 *** findings suggest that the MoSe_(2)@NCNF electrodes may be a promising candidate for use in reversible Li/Na storage applications.

关键词： Li/Na storage Freestanding electrode MoSe_(2) Electrochemical reaction kinetics Structural integrity

Improving hydrogen storage thermodynamics and kinetics of Ce-Mg-Ni-based alloy by mechanical milling with TiF_(3)

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Journal of Magnesium and Alloys 2024年第4期12卷 1593-1607页

作者： Hongwei shang Wei Zhang xin Wei Yaqin Li Zeming Yuan Jun Li Yanghuan Zhang School of Mechanical and Electrical Engineering Chuzhou UniversityChuzhou 239000China Department of Functional Material Research Central Iron and Steel Research InstituteNo.76 Xueyuannan RoadHaidian DistrictBeijing 100081China Key Laboratory of Integrated Exploitation of Bayan-Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010China China Rare Earth New Material(Weishan)Co. Ltd.Jining 277600China

Mg-based hydrides are too stable and the kinetics of hydrogen absorption and desorption is not *** efficient way to improve these shortcomings is to employ reactive ball milling to synthesize the nanocomposite materials of Mg and *** this experiment,TiF_(3)was selected as an additive,and the mechanical milling method was employed to prepare the experimental *** alloys used in this experiment were the as-cast Ce_(5)Mg_(85)Ni_(10),as-milled Ce_(5)Mg_(85)Ni_(10)and Ce_(5)Mg_(85)Ni_(10)+3 wt.%*** phase transformation,structural evolution,isothermal and non-isothermal hydrogenation and dehydrogenation performances of the alloys were inspected by XRD,SEM,TEM,Sievert apparatus,DSC and *** revealed that nanocrystalline appeared in the as-milled *** with the as-cast alloy,ball milling made the particle dimension and grain size decrease dramatically and the defect density increase *** addition of TiF_(3)made the surface of ball milling alloy particles markedly coarser and more *** milling and adding TiF_(3)distinctly improved the activation and kinetics of the ***,ball milling along with TiF_(3)can decrease the onset dehydrogenation temperature of Mg-based hydrides and slightly ameliorate their thermodynamics.

关键词： Mg-based hydrides TiF_(3) Ball milling Thermodynamics Kinetics

Taiji-TianQin-LISA network:Precisely measuring the Hubble constant using both bright and dark sirens

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 59-77页

作者： shang-Jie Jin Ye-Zhu Zhang Ji-Yu Song Jing-Fei Zhang xin Zhang Key Laboratory of Cosmology and Astrophysics(Liaoning)&College of Sciences Northeastern UniversityShenyang 110819China Key Laboratory of Data Analytics and Optimization for Smart Industry(Ministry of Education) Northeastern UniversityShenyang 110819China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern UniversityShenyang 110819China

In the coming decades,the space-based gravitational-wave(GW)detectors such as Taiji,TianQin,and LISA are expected to form a network capable of detecting millihertz GWs emitted by the mergers of massive black hole binaries(MBHBs).In this work,we investigate the potential of GW standard sirens from the Taiji-TianQin-LISA network in constraining cosmological *** the optimistic scenario in which electromagnetic(EM)counterparts can be detected,we predict the number of detectable bright sirens based on three different MBHB population models,i.e.,popⅢ,Q3d,and *** results show that the TaijiTianQin-LISA network alone could achieve a constraint precision of 0.9%for the Hubble constant,meeting the standard of precision ***,the Taiji-TianQin-LISA network could effectively break the cosmological parameter degeneracies generated by the CMB data,particularly in the dynamical dark energy *** combined with the CMB data,the joint CMB+Taiji-TianQin-LISA data offerσ(w)=0.036 in the wCDM model,which is close to the latest constraint result obtained from the CMB+SN *** also consider a conservative scenario in which EM counterparts are not *** to the precise sky localizations of MBHBs by the Taiji-TianQin-LISA network,the constraint precision of the Hubble constant is expected to reach 1.2%.In conclusion,the GW standard sirens from the Taiji-TianQin-LISA network will play a critical role in helping solve the Hubble tension and shedding light on the nature of dark energy.

关键词： space-based gravitational wave detection standard sirens the Taiji-TianQin-LISA network the Hubble constant dark energy

Investigation on the vortical structures by the Liutex method in turbulent channels at Re_(τ)=180 with scalloped and triangular riblet control

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Journal of Hydrodynamics 2024年第1期36卷 35-52页

作者： Zhang-dan Yu shang Jiang Hai-dong Yu Bi-yu Pang xin Dong Yi-qian Wang School of Mathematical Sciences Soochow UniversitySuzhou215006China Beijing Institute of Astronautical System Engineering Beijing100076China

Riblets are a series of small protrusions formed along the flow direction,which have been extensively studied as a passive turbulent drag reduction *** and numerical simulations have shown that well-designed riblets can significantly reduce drag in turbulent flows,making them highly promising and valuable for various *** this study,we focus on a scalloped riblet,which is designed by smoothly connecting two third-order polynomials,and thus the sharpness of the tip and the curvature of the valley can be well *** conduct direct numerical simulations of turbulent channel with smooth plate,scalloped riblet-mounted and triangular riblet-mounted *** in wall units of W^(+)=20 and height-width ratio ofγ=0.5 are selected for both riblet *** with the smooth plate case,the scalloped riblet case achieves an 8.68%drag reduction,while the triangular riblet case achieves a 4.79%drag *** obtained drag reduction rate of the triangular riblet is consistent with previous experiments and simulations,and the results indicate that the scalloped riblet is more effective in reducing drag and deserves further *** compare turbulent statistics of the scalloped riblet case with those of the triangular riblet *** mean velocity profiles of riblets are similar,but both the Reynolds shear stress and second-order statistics of velocity fluctuations and Liutex are significantly reduced in the scalloped riblets controlled turbulent channel,indicating that the scalloped riblet can more effectively suppress the spanwise and wall-normal turbulent intensity near the *** also compare the pre-multiplied spectra of streamwise velocity and streamwise Liutex component for the three cases to investigate the energy distribution and characteristics of Liutex *** Liutex vortex identification method is also utilized to analyze the instantaneous flow field,which provides insights into the flow field and could be bene

关键词： Liutex vector riblet drag reduction tip sharpness turbulent channel scalloped

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色谱峰纯度检查中的统计概率估计

中国临床药理学与治疗学 2006年第8期11卷 947-951页

作者：尚尔鑫相秉仁中国药科大学分析测试中心

目的将傅立叶变换去卷积方法用于峰纯度检查,并在此基础上建立峰纯度检查的概率模型,给出有准确率的判断结果。方法以计算机模拟大量各种重叠色谱峰,对每个重叠色谱峰计算能将其准确判断为重叠峰时的去卷积函数的最小标准偏差,将其记录... 详细信息

目的将傅立叶变换去卷积方法用于峰纯度检查,并在此基础上建立峰纯度检查的概率模型,给出有准确率的判断结果。方法以计算机模拟大量各种重叠色谱峰,对每个重叠色谱峰计算能将其准确判断为重叠峰时的去卷积函数的最小标准偏差,将其记录下来做为观测值。在积累了大量观测值后,计算经验累积分布曲线。实际做出判断时,从该曲线上即可得到判断的准确率。结果成功建立了色谱峰纯度检查的概率模型,并应用于实践,取得较好效果。结论峰纯度检查的概率模型可以提高判断结果的可靠性,适合实际分析工作需要。

关键词：色谱峰纯度傅立叶去卷积累积分布曲线计算机模拟

Single-atom-mediated electron islands boost photocatalytic CO_(2)chemical fixation

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Science China Chemistry 2024年第7期67卷 2292-2299页

作者： Shu shang Lei Li xin He Hui Wang Lirong Zheng Wei Shao Xiaodong Zhang Yi Xie Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China Institute of Energy Hefei Comprehensive National Science CenterHefei 230031China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Chemistry and Chemical Engineering Hefei Normal UniversityHefei 230031China

Photocatalytic cycloadditions of CO_(2)with epoxides are emerging as a significant platform for the green synthesis of valuable carbonates,where efficient catalytic systems with spatially separated charge carriers are ***,a single p-block metal atom is proposed to be a candidate for photogenerated electron localization on a metal oxide *** taking the Bi single-atom supported on ZnO nanosheet(Bi1/ZnO)as an example,we show that the Bi atom plays the role of an electron island in the sea of delocalized holes within ***,the as-formed electron island could readily promote the rate-determining ring-opening process of cycloaddition *** from the unique spatially separated electrons and holes,the Bi1/ZnO achieves a high yield of cyclic carbonates with almost 100%*** study provides a pioneering strategy for enhancing the performances of photocatalytic CO_(2)chemical fixation.

关键词： electron islands CO_(2)photofixation photogenerated charge carriers