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design and synthesis of liquid crystal copolyesters with high-frequency low dielectric loss and inherent flame retardancy

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Chinese Chemical Letters 2023年第5期34卷 621-625页

作者： Shi-Yu Zhang Teng Fu Yue Gong de-ming guo Xiu-Li Wang Yu-Zhong Wang State Key Laboratory of Polymer Materials Engineering The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric MaterialsNational Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)College of ChemistrySichuan UniversityChengdu 610064China

Ultra-low dielectric loss(Df)and low dielectric constant(Dk)materials are urgently required in highspeed and large-capacity transmission,in which the wholly aromatic liquid crystal polymer(LCP)has gained attention due to its excellent dielectric ***,the relationship between molecular structure and dielectric properties is still not *** this study,two copolyesters containing phenyl or naphthyl structures are synthesized,as well as the effects of benzene and naphthalene mesogens on dielectric properties are *** synthesized copolyesters containing naphthalene structure have good comprehensive properties with high thermal stability(T_(5%)=479℃ and T_g=195-216℃),inherent flame retardance(LOI=33.0-35.0 and UL-94 V-0 level at 0.8 mm),low Dk(2.9-3.0@10 GHz)and low Df(0.0027-0.0047@10 GHz).Naphthalene mesogen can reduce the dielectric loss more significantly than benzene at high frequency by reducing the density and mobility of polarizable groups,which leads to the effectively limited dipole polarization in ***,we proposed a new strategy for designing low Dk and low Df materials.

关键词： Liquid crystal polymer Low dielectric loss Low dielectric constant Naphthalene structure Flame retardant

A bio-based epoxy resin derived from p-hydroxycinnamic acid with high mechanical properties and flame retardancy

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Chinese Chemical Letters 2022年第11期33卷 4912-4917页

作者： Xin Song Ze-Peng deng Chun-Bo Li Fei Song Xiu-Li Wang Li Chen de-ming guo Yu-Zhong Wang The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MoE) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)State Key Laboratory of Polymer Materials EngineeringCollege of ChemistrySichuan UniversityChengdu 610064China

Recent advances in epoxy resins have been forward to achieving high mechanical performance,thermal stability,and flame ***,seeking sustainable bio-based epoxy precursors and avoiding introduction of additional flame-retardant agents are still of increasing *** we report the synthesis of p-hydroxycinnamic acid-derived epoxy monomer(HCA-EP)via a simple one-step reaction,and the HCA-EP can be cured with 4,4′-diaminodiphenylmethane(DDM)to prepare epoxy *** with the typical petroleum-based epoxy resin,bisphenol A epoxy resin,the HCA-EP-DDM shows a relatively high glass transition temperature(192.9℃)and impressive mechanical properties(tensile strength of 98.3 MPa and flexural strength of 158.9 MPa).Furthermore,the HCA-EP-DDM passes the V-1 flammability rating in UL-94 test and presents the limiting oxygen index of 32.6%.Notably,its char yield is as high as 31.6%under N_(2),and the peak heat rate release is 60%lower than that of bisphenol A epoxy *** findings provide a simple way of using p-hydroxycinnamic acid instead of bisphenol A to construct high-performance bio-based thermosets.

关键词： Epoxy resin Bio-based p-Hydroxycinnamic acid Mechanical performance Intrinsic flame retardancy

ALUMINUM CONTENT OF TEA LEAVES AND FACTORSAFFECTING THE UPTAKE OF ALUMINUM FROMSOIL INTO TEA LEAVES

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Chinese Geographical Science 2001年第1期11卷 87-91页

作者： XIE Zhong-lei, DONG de-ming, BAO guo-zhang, WANG Sheng-tian, DU Yao-guo,QIU Li-min (department of Environmental Science and Engineering, Jilin University, Changchun 130023, P. R. China department of Chemistry, Northeast Normal University, Changchun 13002 department of Environmental Science and Engineering Jilin University Changchun P. R. China department of Chemistry Northeast Normal University Changchun P. R. China

Numerous studies indicated that aluminum, the most abundant metallic element within the lithosphere, was considered to be related to some human diseases especially the Alzheimer’s disease. Tea, economically an important beverage in the world, has been found to contain higher concentration of aluminum than many other drinks and foods. Therefore, tea would be a potentially important source of dietary aluminum. In order to understand the sources of aluminum in tea leaves and factors related with aluminum content of tea leaves, an experiment was designed to investigate the relationships of aluminum in tea leaves with leaf age, soil properties and forms of aluminum in soils. The results showed that there were great distinctions in the concentration of aluminum in tea leaves with different leaf age (Alold leaf> Almature leaf> Alyoung leaf). Moreover, soil pH was the major factor controlling the uptake of aluminum from soil into tea leaves. Furthermore, the content of aluminum in tea leaves was better predicated by the soluble aluminum extracted by 0.02mol/L CaCl2.

关键词： aluminum tea leaf soil properties

Catalytic Performance of Carbon Smoke over Ag-LSCF Composite Catalysts

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 30-34页

作者： guo Guanlun HAN ming LU Shaomin YU Jing JU Hongling 无 Hubei Key Laboratory of Advanced Technology for Automotive Components&Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan University of TechnologyWuhan 430070China College of Mechanical and Transportation Southwest Forestry UniversityKunming 650000China

To improve the catalytic performance of La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3)(LSCF)towards carbon soot,we utilized the impregnation method to incorporate Ag into the prepared LSCF *** conducted a series of characterization tests and evaluated the soot catalytic activity of the composite catalyst by comparing it with the LaCoO_(3) group,LaFeO_(3) group,and catalyst-free *** results indicate that the Ag-LSCF composite catalyst exhibits the highest soot catalytic activity,with the characteristic temperature values of 376.3,431.1,and 473.9℃at 10%,50%,and 90%carbon soot conversion,*** values are 24.8,20.2,and 23.1℃lower than those of the LSCF *** also shows that LSCF can improve the catalytic activity of soot after compounding with Ag,and reflects the necessity of using catalysts in soot combustion *** characterization and BET test show that Ag-LSCF has more abundant surface-adsorbed oxygen species,larger specific surface area and pore volume than LSCF,which also proves that Ag-LSCF has higher soot catalytic activity.

关键词： metallic composites carbon smoke oxidation perovskite catalyst soot

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“限制人身自由”卫生即时强制的立法研究

西部法学评论 2009年第3期 115-119页

作者：杜国明华南农业大学法学院广东广州510642

在我国,"限制人身自由"卫生即时强制属于卫生行政执法实践中应用不少而在理论上关注不多、研究不深的一类行政强制措施。随着"SARS"、禽流感等传染病的发生,凸现了我国"限制人身自由"卫生即时强制相关法规中存在的问题。对此,我国应加... 详细信息

在我国,"限制人身自由"卫生即时强制属于卫生行政执法实践中应用不少而在理论上关注不多、研究不深的一类行政强制措施。随着"SARS"、禽流感等传染病的发生,凸现了我国"限制人身自由"卫生即时强制相关法规中存在的问题。对此,我国应加强与之相关的多个层次、多个部门法律法规的完善。

关键词：限制人身自由卫生即时强制立法

A versatile synthetic strategy towards rare earth based metal-organic frameworks

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Science China Chemistry 2025年

作者： Quan Shi Yun-Hao Xu ming-Hui Chen Peng Zhao Wen-Bo deng Ji Xiong Kai guo Ya-Qing Feng Bao Zhang School of Chemical Engineering and Technology Tianjin University Tianjin Collaborative Innovation Center of Chemical Science and Engineering Guangdong Laboratory Chemistry & Fine Chemical Industry Jieyang Center

Rare earth metal-organic frameworks (RE-MOFs) have drawn wide attention owing to diverse network structures and various application ***,due to the unpredictable formation of the nodes,it is still challenging to design novel RE-MOFs.A novel versatile strategy was developed employing a RE-acetate complex (RE2(CH3COO)6·4H2O) as a precursor to construct RE-MOFs.2D RE-MOFs (RE-DBP) and 3D RE-MOFs (RE-TCPP) could be obtained by using dicarboxylic porphyrin ligands H2DBP and tetracarboxylic porphyrin ligands H2TCPP,*** RE-MOFs were further synthesized to verify the universality of the *** crystalline RE-MOFs could also be prepared at room temperature via the developed strategy,which could significantly promote large-scale preparation and practical application of *** proof of the concept,the performance of porphyrin-based RE-MOFs was investigated in the photocatalytic cycloaddition of CO2with *** the RE-DBP(Co) MOFs,Tb-DBP(Co) exhibited the best photocatalytic performance,which was also greater than that of the corresponding 3D MOF Tb-TCPP(Co) due to the optimal 2D structure and thus the accelerated photogenerated charge separation and transfer *** work not only provides a novel versatile strategy to design and develop RE-MOFs,but also proposes a promising approach for the potential bulk production of RE-MOFs at room temperature.

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Palladium installed copper-organic framework for C–C coupling reactions

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Science China Chemistry 2025年

作者： Yu-Mei Wang Mei-Xia Tao Kai-ming Mo Xu Chen Shu-Hua Zhong Elena S Shubina guo-Hong Ning Dan Li College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Supramolecular Coordination ChemistryJinan University A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of Sciences

The formation of C–C bonds is a crucial aspect of organic synthesis. Synthesists' long-term objective is to identify novel catalysts to optimize reaction systems based on traditional transition metal catalysis. This study explores the synthesis and catalytic potential of palladium-installed covalent metal-organic frameworks(CMOFs) based on copper cyclic trinuclear units(Cu-CTUs). By incorporating palladium ions into the imine-based framework JNM-7 through a straightforward immersion method, we achieved a notable enhancement in catalytic activity for critical C–C coupling reactions, including C–H arylation and Sonogashira cross-coupling. The resulting JNM-7-Pd demonstrated remarkable stability and recyclability, maintaining its efficiency over at least three cycles without any decline in efficiency.

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轻子混合与中微子振荡

兰州大学学报 1983年第1期 31-35页

作者：辛明德国晓蔚

本文在SU(2)_L×SU(2)_R×U(1)模型中讨论中微子的混合问题,计及轻子的质量特征,对轻子与Hjggs场的相互作用耦合常数作了若干假定,定量地研完了中微子的振荡现象,并对中微子振荡与其质量关系进行了若干分析和讨论,得到与现有实验符合的... 详细信息

本文在SU(2)_L×SU(2)_R×U(1)模型中讨论中微子的混合问题,计及轻子的质量特征,对轻子与Hjggs场的相互作用耦合常数作了若干假定,定量地研完了中微子的振荡现象,并对中微子振荡与其质量关系进行了若干分析和讨论,得到与现有实验符合的结果。

关键词：中微子振荡振荡现象轻子费米子轻子质量

circT P63-N suppresses the proliferation and metastasis of nasopharyngeal carcinoma via engaging with HSP90AB1 to modulate the YAP1/Hippo signaling pathway

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Science China Life Sciences 2025年

作者： Dan Wang Sicheng Zuo Junshang Ge Hongke Qu Jie Wu Na Yi Lei Shi Yumin Wang Yongzhen Mo Chunmei Fan Yi He Pan Chen ming Zhou Bo Xiang Wei Xiong Wenjia guo Zhaoyang Zeng Can guo NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine Central South University Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education Cancer Research Institute and School of Basic Medicine Sciences Central South University Furong Laboratory Cancer Research Institute Affiliated Cancer Hospital of Xinjiang Medical University Xinjiang Key Laboratory of Translational Biomedical Engineering

Circular RNAs(circRNAs) play pivotal roles in the development and progression of various diseases, including malignant tumors. However,the biological functions and the underlying mechanisms of many circRNAs remain elusive. In this study, we identified a novel circRNA,circTP63-N, generated through the splicing of exons 2–4 of the TP63 gene in nasopharyngeal carcinoma(NPC). circTP63-N was found to be downregulated in clinical samples of NPC. Both in vitro and in vivo experiments unequivocally demonstrated that circTP63-N inhibits the proliferation and metastasis of NPC cells. Further investigations revealed that circTP63-N interacted with the HSP90AB1 protein, leading to the recruitment of LATS/YAP1 proteins. This, in turn, induced phosphorylation and ubiquitination-dependent degradation of YAP1, resulting in reduced nuclear translocation of YAP1 and inhibition of the transcriptional activation of downstream oncogenic genes, including INHBA, MMP3, and CCNE2. Our findings highlight the identification of circTP63-N, a novel circRNA encoded by an important tumor-relevant gene TP63 and elucidate its molecular mechanism as a tumor suppressor in NPC. These insights offer novel potential molecular markers and therapeutic targets for the clinical diagnosis and treatment of NPC.

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