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Catalytic hydrative cyclization of aldehyde-ynamides with water for synthesis of medium-sized lactams

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Science China Chemistry 2021年第11期64卷 1985-1989页

作者： Bo-Han Zhu yan-xin zheng Wei Kang Chao Deng Jin-Mei Zhou Long-Wu Ye Key Laboratory of Chemical Biology of Fujian Province State Key Laboratory of Physical Chemistry of Solid SurfacesCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry College of SciencesNanjing Agricultural UniversityNanjing210095China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China

A non-noble metal catalyzed hydrative cyclization of aldehyde-ynamides for efficient and practical synthesis of medium-sized lactams(7-to 9-membered rings)is *** with previous hydrative cyclization for the formation of six-membered lactams(cis-form),a totally inverse diastereoselectivity(trans-form)of medium-sized lactams is *** addition,this protocol delivers valuable medium-sized lactams in moderate to good yields with high ***,a rational mechanism to understand this inversion of diastereoselectivity is proposed based on theoretical calculations.

关键词： ynamides cyclization lactams diastereoselectivity N-heterocycles

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入射激波诱导环氧丙烷爆炸特征研究

原子与分子物理学报 2011年第3期28卷 479-484页

作者：炎正馨西安科技大学理学院西安710054

用自行设计激波管点火测试技术,实验研究了温度范围760～1380 K间入射激波诱导下环氧丙烷的点火机理.利用激波管压力传感器测定了H*(486.1)和O(470.5 nm)随激波诱导强度变化的点火时间特征.实验结果表明:在低马赫数下氢氧自由基出现时... 详细信息

用自行设计激波管点火测试技术,实验研究了温度范围760～1380 K间入射激波诱导下环氧丙烷的点火机理.利用激波管压力传感器测定了H*(486.1)和O(470.5 nm)随激波诱导强度变化的点火时间特征.实验结果表明:在低马赫数下氢氧自由基出现时间较接近,1.5～2.5马赫间随激波诱导强度增大而线性减小;而马赫大于2.5后,氧自由基的出现时间迅速减小,是由于高活化能的氧自由基的点火时间对强激波较敏感,而诱导强度大于3.5马赫后对两者点火影响区别就下明显了.实验数据将有益于含能材料点火时间的研究.

关键词：环氧丙烷入射激波点火时间

Combined ATAC-seq,RNA-seq,and GWAS analysis reveals glycogen metabolism regulatory network in Jinjiang oyster(Crassostrea ariakensis)

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Zoological Research 2024年第1期45卷 201-214页

作者： Biao Wu Xi Chen Jie Hu Zhen-Yuan Wang yan Wang Da-You Xu Hao-Bing Guo Chang-Wei Shao Li-Qing Zhou Xiu-Jun Sun Tao Yu Xiao-Mei Wang yan-xin zheng Guang-Yi Fan Zhi-Hong Liu State Key Laboratory of Mariculture Biobreeding and Sustainable Goods Yellow Sea Fisheries Research InstituteChinese Academy of Fishery SciencesQingdaoShandong 266071China Laboratory for Marine Fisheries Science and Food Production Processes Laoshan LaboratoryQingdaoShandong 266071China BGI-Qingdao BGI-ShenzhenQingdaoShandong 266426China National Demonstration Center for Experimental Fisheries Science Education Shanghai Ocean UniversityShanghai 201306China Changdao Enhancement and Experiment Station Chinese Academy of Fishery SciencesYantaiShandong 265800China State Key Laboratory of Agricultural Genomics BGI-ShenzhenShenzhenGuangdong 518083China

Glycogen serves as the principal energy reserve for metabolic processes in aquatic shellfish and substantially contributes to the flavor and quality of *** Jinjiang oyster(Crassostrea ariakensis)is an economically and ecologically important species in *** the present study,RNA sequencing(RNA-seq)and assay for transposase-accessible chromatin using sequencing(ATAC-seq)were performed to investigate gene expression and chromatin accessibility variations in oysters with different glycogen *** identified 9483 differentially expressed genes(DEGs)and 7215 genes with significantly differential chromatin accessibility(DCAGs)were obtained,with an overlap of 2600 genes between ***,a significant proportion of these genes were enriched in pathways related to glycogen metabolism,including“Glycogen metabolic process”and“Starch and sucrose metabolism”.In addition,genome-wide association study(GWAS)identified 526 single nucleotide polymorphism(SNP)loci associated with glycogen *** loci corresponded to 241 genes,63 of which were categorized as both DEGs and *** study enriches basic research data and provides insights into the molecular mechanisms underlying the regulation of glycogen metabolism in ***.

关键词： Crassostrea ariakensis Glycogen Transcriptome ATAC GWAS

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苯快速反应点火特性的光谱研究

光谱学与光谱分析 2007年第12期27卷 2396-2398页

作者：吴旌贺炎正馨叶松胡栋杨向东四川大学原子与分子物理研究所四川成都610065 中国工程物理研究院流体物理研究所冲击波物理与爆轰物理国家级重点实验室四川绵阳621900

利用由单色谱仪、压力传感器以及示波器组成的测试系统,测定了高温激波管中苯快速反应的几个重要产物:H,C2和CH的点火延迟时间和出现的顺序。提出了一种在入射激波条件下确定含能材料冲击点火延迟时间的新方法,并介绍了苯在快速反应中... 详细信息

利用由单色谱仪、压力传感器以及示波器组成的测试系统,测定了高温激波管中苯快速反应的几个重要产物:H,C2和CH的点火延迟时间和出现的顺序。提出了一种在入射激波条件下确定含能材料冲击点火延迟时间的新方法,并介绍了苯在快速反应中碳生成的微观反应机理。研究表明:无论马赫数如何改变,H原子总是最先出现,说明苯在快速反应过程中,首先断裂的C—H键,而不是C—C键。利用较早出现的反应中间产物H原子来测定苯的点火延迟时间更为准确。利用单色谱仪技术能较好地研究苯的快速反应点火特性,新方法与国内外常用的全色光技术相比可明显减少实验量。

关键词：瞬态谱测试技术苯反应动力学点火延迟

Small modifications of endo-functionalized cavities lead to large changes in molecular interaction in water

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Science China Chemistry 2025年第1期68卷 369-376页

作者： Song-Meng Wang Hao Nian yan-Fang Wang Li-Shuo zheng Yu-Tao zheng Yi-Wei Dong Liping Huang Xiaoping Wang Wei Jiang Liu-Pan yang Department of Chemistry Southern University of Science and Technology School of Chemistry and Pharmaceutical Sciences State Key Laboratory for Chemistry and Molecular Engineering of Medicinal ResourcesGuangxi Normal University School of Pharmaceutical Science Hengyang Medical School University of South China

Studying molecular recognition in aqueous environments is crucial for understanding biological processes. Herein, we present a series of N-doped endo-functionalized anthracene-based cavities by introducing inward-directed pyridine units. The subtle modifications can significantly affect the binding properties of these receptors, which is similar to the mutations in biological systems. Combining theoretical calculations and molecular recognition experiments demonstrated that these “mutations” have an impact on the hydrophobicity and charge distribution of the hosts, consequently significantly influencing molecular *** is crucial for understanding the intricate mechanisms of molecular-level interactions in biological receptors.

关键词： host-guest interaction hydrophobic effect endo-functionalized cavity mutation pyridine

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铝粉点火微观机理的光谱研究

高压物理学报 2006年第3期20卷 237-242页

作者：胡栋叶松吴旌贺炎正馨李萍孙珠妹中国工程物理研究院流体物理研究所冲击波物理与爆轰物理实验室四川绵阳621900 四川大学高温高压物理研究所四川成都610065

铝粉是一种含能高的材料,它被广泛地添加到含能材料中。利用3台单色谱仪和OMA谱仪等多种谱仪技术,研究了铝粉在几种不同环境下的快速反应微观特性。研究表明:铝粉冲击波点火的临界条件和铝粉的物理状态相关。微米铝粉点火的临界温度为2 ... 详细信息

铝粉是一种含能高的材料,它被广泛地添加到含能材料中。利用3台单色谱仪和OMA谱仪等多种谱仪技术,研究了铝粉在几种不同环境下的快速反应微观特性。研究表明:铝粉冲击波点火的临界条件和铝粉的物理状态相关。微米铝粉点火的临界温度为2 100 K,它接近Al2O3的熔化温度。它表明,在空气中容易氧化的微米铝粉点火,必须使铝粉表面的氧化层熔化。在气相反应中,微米铝粉和氧的反应是主要的;和水的反应是次要的。减小微米铝粉的颗粒尺寸,可以明显提高快速反应温度。含铝复合燃料中的液体燃料反应后的铝粉才能参与反应;铝粉添加至气相反应介质后将明显提高反应温度。

关键词：铝粉点火微观机理光谱技术

Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis

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Neural Regeneration Research 2025年第4期20卷 1103-1123页

作者： Xiahong Tang Nan zheng Qingming Lin yan You zheng Gong yangping Zhuang Jiali Wu Yu Wang Hanlin Huang Jun Ke Feng Chen Shengli Clinical Medical College of Fujian Medical University Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Emergency Fujian Provincial HospitalFuzhouFujian ProvinceChina Fujian Provincial Key Laboratory of Emergency Medicine FuzhouFujian ProvinceChina The Second Department of Intensive Care Unit Fujian Provincial Hospital South BranchFuzhouFujian ProvinceChina

Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological *** preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are *** this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB ***,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by *** results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these *** conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning.

关键词： bone marrow–derived mesenchymal stem cells cardiac arrest cardiac resuscitation hypoxic preconditioning liver isoform of phosphofructokinase mitochondria neuroinflammation oxidative stress pyroptosis reactive oxygen species

A Verifiable Trust-Based CP-ABE Access Control Scheme for Cloud-Assisted Renewable Energy Systems

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Computers, Materials & Continua 2025年第1期82卷 1211-1232页

作者： Jiyu Zhang Kehe Wu Ruomeng yan zheng Tian Yizhen Sun Yuxi Wu Yaogong Guo Department of Control and Computer Engineering North China Electric Power UniversityBeijing102206China State Grid Information&Communication Company of Hunan Electric Power Corporation Changsha410118China State Grid Hunan Electric Power Corporation Chenzhou Power Supply Branch Chenzhou423000China

Renewable Energy Systems(RES)provide a sustainable solution to climate warming and environmental pollution by enhancing stability and reliability through status acquisition and analysis on cloud platforms and intelligent processing on edge servers(ES).However,securely distributing encrypted data stored in the cloud to terminals that meet decryption requirements has become a prominent research ***,managing attributes,including addition,deletion,and modification,is a crucial issue in the access control scheme for *** address these security concerns,a trust-based ciphertext-policy attribute-based encryption(CP-ABE)device access control scheme is proposed for RES(TB-CP-ABE).This scheme effectivelymanages the distribution and control of encrypted data on the cloud through robust attribute key *** introducing trust management mechanisms and outsourced decryption technology,the ES system can effectively assess and manage the trust worthiness of terminal devices,ensuring that only trusted devices can participate in data exchange and access sensitive ***,the ES system dynamically evaluates trust scores to set decryption trust thresholds,thereby regulating device data access permissions and enhancing the system’s *** validate the security of the proposed TB-CP-ABE against chosen plaintext attacks,a comprehensive formal security analysis is conducted using the widely accepted random oraclemodel under the decisional q-Bilinear Diffie-Hellman Exponent(q-BDHE)***,comparative analysis with other schemes demonstrates that the TB-CP-ABE scheme cuts energy/communication costs by 43%,and scaleswell with rising terminals,maintaining average latency below 50ms,ensuring real-time service *** proposed scheme not only provides newinsights for the secure management of RES but also lays a foundation for future secure energy solutions.

关键词： Access control renewable energy systems(RES) ciphertext-policy attribute-based encryption(CP-ABE) security

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甲烷在多孔硅表面物理吸附特征研究(英文)

原子与分子物理学报 2014年第4期31卷 555-559页

作者：闫东芝炎正馨龚安陈倩廖谦西安科技大学理学院西安710054

在密度泛函理论耦合超软贋势第一性原理的平台上,研究了甲烷在Si(111)表面的物理吸附特性.通过建立硅晶胞的不同吸附位置(top、bridge、fcc)模型,对比分析了甲烷在相应位置吸附界面变化的键结构、吸附能和态密度,获得了相应吸附点的吸... 详细信息

在密度泛函理论耦合超软贋势第一性原理的平台上,研究了甲烷在Si(111)表面的物理吸附特性.通过建立硅晶胞的不同吸附位置(top、bridge、fcc)模型,对比分析了甲烷在相应位置吸附界面变化的键结构、吸附能和态密度,获得了相应吸附点的吸附特征.对比分析的结果表明,甲烷只有在fcc位置物理吸附状态较为理想.分析态密度、键长及键角等数据揭示fcc位甲烷吸附对体系硅晶胞有很大的影响,其体系的键能最低,即此时体系结构最稳定.本文所得研究成果可用于Si表面对甲烷气体的敏感性分析及气体传感器领域.

关键词：甲烷硅表面物理吸附密度泛函理论