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A NEW STYRYL-LACTONE COMPOUND FROMGONIOTHALAMUS LEIOCARPUS

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Chinese Chemical Letters 1996年第7期7卷 617-618页

作者： Qing MU Chao Ming LI Hong Jie ZhanG Yu WU and han dong sun(Kunming Institute of Botany, Chinese Academy of Sciences,Kunming 650204) Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204

A new styryl-lactone compound, named as leiocarpin A (1), was isolated from Goniothalamus leiocarpus. Its structure and relative configuration were determined by means of spectrum particularly 2D NMR including H-1-H-1...

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Two New Abietane Quinones from Isodon lophanthoides var. Micranthus

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Chinese Chemical Letters 2003年第6期14卷 591-593页

作者： Ai Hua ZHAO Sheng Hong LI Yong Wei LI Quan Bin HUAN Qin Shi ZHAO Zhong Wen LIN han dong sun State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650204

The structures of two new abietane quinones, named micranthins A and B, were determined to be 7a-methoxy-14, 16-epoxy-8, 13-abietadiene-11, 12-dione (1) and 16-acetoxy-6, 7-dehydroroyleanone (2) respectively, which we... 详细信息

关键词： Isodon lophanthoides var. micranthus Labiatae abietane quinones micranthin A miranthin B.

Characteristics and stability of oxide+carbonitride in H13 steel at 1250℃

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Journal of Iron and Steel Research International 2024年第1期31卷 134-142页

作者： Xiao-lin sun han-jie Guo Jing Guo Fei Wang dong Xu Gao-yang Song Shuai Wang School of Materials Science and Engineering Hebei University of EngineeringHandan056038HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China High Temperature Materials Research Institute Central Iron and Steel Research Institute Co.Ltd.Beijing100081China Technology Innovation Center for High Quality Cold Heading Steel of Hebei Province Hebei University of EngineeringHandan056038HebeiChina

The morphology,size,quantity,and composition of complex oxide+carbonitride in H13 steel held at 1250℃for 5,10,and 15 h were *** results show that the ratio and number of complex carbonitrides with cores in H13 steel are gradually increased when holding at 1250℃compared with those in the original H13 steel,and the core size *** are one or more oxide cores in(Ti_(x),V_(1-x))(Cy,N_(1-y)),including xCaO·zAl_(2)O_(3),xCaO·yMgO·zAl_(2)O_(3),and CaO after holding at 1250℃,in addition to MgO·Al_(2)O_(3)and Al_(2)O_(3)in the original *** equilibrium temperature for(Ti_(x),V_(1-x))(Cy,N_(1-y))precipitation at the solidification front and decomposition in the solid state was theoretically analyzed,which was affected by the x value and the product of Ti and N contents in H13 ***,the composition of(Ti_(x),V_(1-x))(Cy,N_(1-y))is influenced by the oxide *** is convinced that(Ti_(x),V_(1-x))(Cy,N_(1-y))with oxide cores has a higher stability,especially for oxides with a high Al_(2)O_(3)*** treatment at high temperature facilitates a more reasonable analysis of oxide+carbonitride,and the generation mechanism of oxide+carbonitride was discussed.

关键词： Complex carbonitride Decomposition Oxide core Characteristic Stability

Chemical studies of the Schisandraceae family

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Chemical studies of the Schisandraceae family

A New Method for Solving Nonlinear Partial Differential Equations Based on Liquid Time-Constant Networks

中国化学会第十届全国天然有机化学学术会议

作者： han-dong sun State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences

＜正＞Many medicinal plants of the Schisandraceae family,known as famous traditional Chinese Medicine"wuweizi",have been used as sedative and tonic agents for a long ***,the relationships between chemical constituents and biological functions,especially who served as sedative and tonic functions,are still not clear ***,further studies on this relationship in

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来源： cnki会议评论

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cnki会议

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Journal of Systems Science & Complexity 2024年第2期37卷 480-493页

作者： sun Jiuyun dong Huanhe FANG Yong College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

In this paper,physics-informed liquid networks(PILNs)are proposed based on liquid time-constant networks(LTC)for solving nonlinear partial differential equations(PDEs).In this approach,the network state is controlled via ordinary differential equations(ODEs).The significant advantage is that neurons controlled by ODEs are more expressive compared to simple activation *** addition,the PILNs use difference schemes instead of automatic differentiation to construct the residuals of PDEs,which avoid information loss in the neighborhood of sampling *** this method draws on both the traveling wave method and physics-informed neural networks(PINNs),it has a better physical ***,the KdV equation and the nonlinear Schr¨odinger equation are solved to test the generalization ability of the *** the best of the authors’knowledge,this is the first deep learning method that uses ODEs to simulate the numerical solutions of PDEs.

关键词： Nonlinear partial differential equations numerical solutions physics-informed liquid networks physics-informed neural networks

High leaf area index expands the contrasting effect of climate warming on Western Siberia taiga forests activity before and after 2000

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Journal of Geographical Sciences 2024年第1期34卷 131-145页

作者： sun han WANG Xiangping State Key Laboratory of Efficient Production of Forest Resources Beijing Forestry UniversityBeijing 100083China School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing 100083China

The taiga vegetation in Western Siberia has been seriously threatened by climate warming in recent ***,how vegetation in different growing states and climate conditions responds to climate changes differently is still *** we explore the vegetation activity trends in Western Siberia taiga forests using the annual rate of change in leaf area index(LAI)during 1982–2018 so as to answer two questions:(1)how did climate warming affect taiga vegetation activity in the recent last decades?(2)Did the growing state of taiga forest affect its response to climate warming?Our results revealed that climate warming promoted taiga vegetation activity in Western Siberia before ***,continuous warming caused excessive evapotranspiration and led to decreased vegetation activity after ***,the intensity of vegetation growth response to warming was positively related to canopy height and LAI,indicating that both the positive and negative effects of warming were more significant in taiga forests in better growing *** these forests generally have higher productivity and play more important roles in ecosystem functioning(e.g.,carbon sink and biodiversity conservation),our results highlight their vulnerability to future climate change that need more research attention.

关键词： climate warming taiga forest leaf area index(LAI) vegetation activity Western Siberia

On asymptotic stability of the 3D Boussinesq equations without heat conduction

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Science China Mathematics 2024年第2期67卷 253-280页

作者： Lihua dong Yongzhong sun School of Physical and Mathematical Sciences Nanjing Tech UniversityNanjing 211816China Department of Mathematics Nanjing UniversityNanjing 210093China

We investigate the asymptotic stability of the solutions to Boussinesq equations without heat conduction with the initial data near a specific stationary solution in the three-dimensional domain Ω=R^(2)×(0,1).It is shown that the solution starting from a small perturbation to the stationary solution converges to it with explicit algebraic rates as time tends to infinity.

关键词： Boussinesq equations stationary solutions asymptotic stability decay rates

A Wnt10a-Notch signaling axis controls Hertwig’s epithelial root sheath cell behaviors during root furcation patterning

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International Journal of Oral Science 2024年第3期16卷 425-435页

作者： Kai sun Miao Yu Jiayu Wang Hu Zhao Haochen Liu Hailan Feng Yang Liu dong han Department of Prosthodontics Peking University School and Hospital of Stomatology&National Center for Stomatology&National Clinical Research Center for Oral Diseases&National Engineering Research Center of Oral Biomaterials and Digital Medical DevicesBeijingChina Chinese Institute for Brain Research BeijingChina

Human with bi-allelic WNT10A mutations and epithelial Wnt10a knockout mice present enlarged pulp chamber and apical displacement of the root furcation of multi-rooted teeth,known as taurodontism;thus,indicating the critical role of Wnt10a in tooth root ***,the endogenous mechanism by which epithelial Wnt10a regulates Hertwig’s epithelial root sheath(HERS)cellular behaviors and contributes to root furcation patterning remains *** this study,we found that HERS in the presumptive root furcating region failed to elongate at an appropriate horizontal level in K14-Cre;Wnt10a^(fl/fl)mice from post-natal day 0.5(PN0.5)to *** assays and immunofluorescent staining of cyclin D1 revealed significantly decreased proliferation activity of inner enamel epithelial(IEE)cells of HERS in K14-Cre;Wnt10a^(fl/fl)mice at PN2.5 and *** staining of E-Cadherin and acetyl-α-Tubulin demonstrated that the IEE cells of HERS tended to divide perpendicularly to the horizontal plane,which impaired the horizontal extension of HERS in the presumptive root furcating region of K14-Cre;Wnt10a^(fl/fl)***-seq and immunofluorescence showed that the expressions of Jag1 and Notch2 were downregulated in IEE cells of HERS in K14-Cre;Wnt10a^(fl/fl)***,after activation of Notch signaling in K14-Cre;Wnt10a^(fl/fl)molars by Notch2 adenovirus and kidney capsule grafts,the root furcation defect was partially *** together,our study demonstrates that an epithelial Wnt10a-Notch signaling axis is crucial for modulating HERS cell proper proliferation and horizontal-oriented division during tooth root furcation morphogenesis.

关键词： Wnt10a Notch impaired

A New Abietane Diterpenoid from Orthosiphon wulfenioides

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Chinese Chemical Letters 2002年第2期13卷 141-142页

作者： Wei XIANG Sheng Hong LI Qin Shi ZHAO Zhi NA Bei JIANG Hong Jie ZhanG Zhong Wen LIN han dong sun Laboratory of Phytochemistry Kunming Institute of BotanyChinese Academy of SciencesKunming 650204

A new abietane diterpenoid, orthosiphonol (11-methoxy-12, 14-dihydroxy-8, 11, 13-abieta trien-7-one) (1) together with known 11-hydroxysugiol (2) were isolated from Orthosiphon wulfenioides. Their structures were det... 详细信息

关键词： Orthosiphon wulfenioides abietane diterpenoid orthosiphonol.