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STUDIES ON THE SYNTHESIS OF SINULARIOE-D,SINULARIAL-A AND SINULARIC ACID-A

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Chinese Chemical Letters 1992年第9期3卷 681-682页

作者： yu lin li Ya Cheng XING Xiang Jun yuE The State Key Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry,Lanzhou University,Lanzhou 730000.

A precursor 12 of sinulariol-D,sinularial-A and sinularic acid-A(marine cembranoids)was prepared from geraniol through nine steps

关键词： OH Ph ACID ppm STUDIES ON THE SYNTHESIS OF SINULARIOE-D,SINULARIAL-A AND SINULARIC ACID-A

SYNTHESIS OF 2,3-DEHYDRO-4, 9β-DIHYDROXY-β-DIHYDROAGAROFURAN

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Chinese Chemical Letters 1995年第12期6卷 1037-1040页

作者： Fa Jun NAN Zhao Ming XIONG li Jun liU Tong Shang li yu lin li (State Key Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry,Lanzhou University, Lanzhou 730000) (Department of Chemistry, Hebei University, Baoding 071002)

Dehydro-4β, 9β-dihydraxy-β-dihydroagarofuran (2), possible precursor of 1α,9β- dibenzoylaxy-2β, 3β, 4β-trihydraxy-β-dihydroagarofuran(1), was synthesized from(-) -carvone via thirteensteps.

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遗传算法优化的BP神经网络压电陶瓷蠕变预测

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电机与控制学报 2018年第7期22卷 91-96页

作者：范伟林瑜阳李钟慎华侨大学机电及自动化学院福建厦门361021

针对压电陶瓷驱动器的蠕变误差随时间呈现非线性变化,会严重影响其定位精度的问题,提出遗传算法优化BP神经网络的压电陶瓷蠕变预测算法。采用遗传算法优化了BP神经网络的权值和阈值,构建了基于遗传算法的BP神经网络(GA-BP算法)的蠕变预... 详细信息

针对压电陶瓷驱动器的蠕变误差随时间呈现非线性变化,会严重影响其定位精度的问题,提出遗传算法优化BP神经网络的压电陶瓷蠕变预测算法。采用遗传算法优化了BP神经网络的权值和阈值,构建了基于遗传算法的BP神经网络(GA-BP算法)的蠕变预测模型。用GA-BP算法对压电陶瓷蠕变进行了预测仿真,并将结果与实测数据进行了对比。结果表明,获得的蠕变预测结果与实验数据的最大绝对误差均不超过0.2μm,最大蠕变误差均小于1.5%,最大均方误差仅为0.004 6,因此,GA-BP预测模型可作为预测压电陶瓷蠕变误差的一种有效手段。

关键词：压电陶瓷蠕变神经网络遗传算法预测

工况压力对分层火焰系统中压力振荡的影响（英文）

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推进技术 2016年第10期37卷 1882-1892页

作者：秦皓林宇震李继保北京航空航天大学能源与动力工程学院北京100191 中国航空工业集团公司商用航空发动机有限责任公司上海200241

为了研究工况压力对分层火焰系统中压力振荡频率的影响,通过实验方法测量了不同工况压力下分层火焰燃烧系统中的压力振荡特性,通过基于火焰响应模型的理论分析方法研究了压力振荡频率变化的原因。实验测试结果表明,当进口压力降低从2.6... 详细信息

为了研究工况压力对分层火焰系统中压力振荡频率的影响,通过实验方法测量了不同工况压力下分层火焰燃烧系统中的压力振荡特性,通过基于火焰响应模型的理论分析方法研究了压力振荡频率变化的原因。实验测试结果表明,当进口压力降低从2.6MPa降低至1.4MPa时,压力振荡频率具有规律性的减小约4%;而相对振荡幅值保持在0.2~0.3范围内,没有明显的规律。火焰响应模型的计算结果显示,雾化过程对火焰的响应特性影响最大。

关键词：分层火焰工况压力火焰响应模型

Mainchain conformation ordering self-assembly tailored room temperature phosphorescence emission

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Science China Chemistry 2025年第01期 329-336页

作者： yuzhu li yumeng Gao Feng Tian yu Wang yuan Yao Shaoliang lin Xiang Ma Binbin Xu Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and Engineering East China University of Science and Technology Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences Key Laboratory for Advance Materials and Feringa Noble Prize Scientist Joint Research Centre Frontiers Science for Materiobiology and Dynamic Chemistry School of Chemistry and Molecular Engineering East China University of Science & Technology

Developing organic room-temperature phosphorescence （RTP） materials with a wide range of tunable-emission is significant in expanding the applications of RTP ***,we rationally designed amphiphilic alternating copolymers poly(1,2-bis（4-alkoxyphenyl）ethane-1,2-dione-alt-（ethylene glycol）x)(P（Bz-alt-EGx）) that combined the advantage of alternating benzil and EGxskeleton,and tunable mainchain *** a mainchain conformation ordering assembly （COA） process,P（Bz-alt-EGx） self-assembled into well-defined platelets,and such assemblies emitted blue RTP at ca.425 nm due to the ordered folded-chain conformation and confined *** contrast,traditional self-assembly （TA） of P（Bz-alt-EGx） obtained less ordered aggregates,such as asymmetric worms,vesicles,and rod-like *** resultant less ordered aggregates exhibited yellow-green RTP at ca.550 *** wide-tuning RTP emission in solution （between blue and yellow-green,over125 nm） is realized using the P（Bz-alt-EGx） alternating copolymers under the treatment of different self-assembly *** study uncovers a new strategy to tailor the RTP emission through different self-assembly pathways and holds great promise for the fabrication of advanced optical materials.

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Fine-tuning the spatial allocation of phytohormones for smart canopy, smart breeding, and smart agriculture

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Science China life Sciences 2025年第1期 309-310页

作者： Tao Zhou lin li National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University HuBei HongShan Laboratory

The dual challenges of global climate change and population growth have increased demand for higher crop yields per unit area. The innovative technology of smart agriculture aims to synergize breeding, cultivation, and production through the application of biological and informatics technologies. Historically, the “Green Revolution” introduced semidwarf varieties of certain key crops by utilizing mutations affecting gibberellin pathways, which significantly increased planting densities and yields.

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Analysis of China's venture capital

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Journal of Harbin Institute of Technology(New Series) 2000年第S1期7卷 107-109页

作者： li Peng-yan, CHENG yu-lin, AO li-feng (School of Humanities and Social Sciences, Harbin Institute of Technology, Harbin 150001, China)

Analyzes the necessity and possibility of developing venture capital in China, puts forward a train of thoughts as to how to develop China′s venture capital.

关键词： venture capital neo & Hi tech

Advances in the Development of Gradient Scaffolds Made of Nano-Micromaterials for Musculoskeletal Tissue Regeneration

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NANO-MICRO LETTERS 2025年第1期17卷 1-46页

作者： Fang, Lei lin, Xiaoqi Xu, Ruian liu, Lu Zhang, yu Tian, Feng li, Jiao Jiao Xue, Jiajia Beijing Univ Chem Technol Beijing Lab Biomed Mat Beijing 100029 Peoples R China Beijing Univ Chem Technol State Key Lab Organ Inorgan Composites Beijing 100029 Peoples R China Univ Technol Sydney Fac Engn & IT Sch Biomed Engn Sydney NSW 2007 Australia

This review highlights the gradient variations in the structural composition of musculoskeletal tissues and comprehensively examines recent progress in the fabrication and application of biomimetic gradient scaffolds for musculoskeletal *** challenges and prospects of gradient scaffolds for clinical application are discussed. The intricate hierarchical structure of musculoskeletal tissues, including bone and interface tissues, necessitates the use of complex scaffold designs and material structures to serve as tissue-engineered substitutes. This has led to growing interest in the development of gradient bone scaffolds with hierarchical structures mimicking the extracellular matrix of native tissues to achieve improved therapeutic outcomes. Building on the anatomical characteristics of bone and interfacial tissues, this review provides a summary of current strategies used to design and fabricate biomimetic gradient scaffolds for repairing musculoskeletal tissues, specifically focusing on methods used to construct compositional and structural gradients within the scaffolds. The latest applications of gradient scaffolds for the regeneration of bone, osteochondral, and tendon-to-bone interfaces are presented. Furthermore, the current progress of testing gradient scaffolds in physiologically relevant animal models of skeletal repair is discussed, as well as the challenges and prospects of moving these scaffolds into clinical application for treating musculoskeletal injuries.

关键词： Gradient scaffolds Musculoskeletal tissues Advanced manufacturing Biomaterials Tissue regeneration

MOLECULAR BEAM STUDIES ON OXIDATION OF CO ON Pd WITH DIFFERENT MIXED RATIOS OF P_(CO) TO P_(O2) ~*

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Chinese Chemical Letters 1992年第2期3卷 153-156页

作者： Guang Kang XI Guo Hua liU Geng yu CAO~(**) Sheng lin li Department of Electron Science, Nankai University Tianjin 300071 Dalian Institute of Chemical Physics, CAS, Dalian 116023, China

Here some steady-state experiments on oxidation of CO on Pd were performed on a molecular beam apparatus. It is found that the characteristics of the rate of CO_2 formation r versus substrate temperature T are dependent on the ratio P=P_(CO)/P_(O2) in the mixed beam. These characteristics are related to the complicated interactions of co-adsorbed CO and O particles on Pd surface.

关键词： Pd CO O2 TO P MOLECULAR BEAM STUDIES ON OXIDATION OF CO ON Pd WITH DIFFERENT MIXED RATIOS OF P