检索结果-南通市图书馆

Phenolic glycosides from the stems of Homalium stenophyllum

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Natural Medicines 2021年第3期19卷 225-230页

作者： WU Shou-Yuan BAI Meng ZHOU Qi NONG Xu-Hua CHEN Guang-Ying ZHAO Si-Yu HAN Chang-Ri song xiao-ping Key Laboratory of Tropical Medicinal Resource Chemistry of Ministry of Education Hainan Normal UniversityHaikou 571158China Key Laboratory of Tropical Medicinal Plant Chemistry of Hainan Province Hainan Normal UniversityHaikou 571158China Key Laboratory of Medicinal and Edible Plants Resources of Hainan Province Hainan Vocational University of Science and TechnologyHaikou 571126China School of Chemistry and Chemical Engineering Lingnan Normal UniversityZhanjiang 524048China

The phytochemical investigation of the stems of Homalium stenophyllum afforded seven new phenolic glycosides(1-5 and 8-9)and two known compounds(6 and 7).Their structures were elucidated by comprehensive analyses of NMR spectroscopic,mass spectrometric data and chemical ***,their anti-inflammatory activities against the NO production in LPS-induced macrophages were evaluated.

关键词： Homalium stenophyllum Phenolic glycosides Chemical hydrolysis Anti-inflammatory activity

A Self-Healing Elastomer with Extremely High Toughness Achieved by Acylsemicarbazide Hydrogen Bonding and Cu^(2+)-Neocuproine Coordination Interactions

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第10期42卷 1425-1434,I0007页

作者： xiao-Ming An Yi-ping Wang Tang-song Zhu Chong Xing Xu-Dong Jia Qiu-Hong Zhang Key Laboratory of High Performance Polymer Material and Technology of MOE Department of Polymer Science and EngineeringSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing210093China State Key Laboratory of Coordination Chemistry Nanjing UniversityNanjing210093China

Elastomers with high mechanical toughness can guarantee their durability during service ***-healing ability,as well as recyclability,can also extend the life of materials and save the consuming cost of the *** efforts have been dedicated to promoting the mechanical toughness as well as the self-healing capability of elastomers at the same time,while it remains a challenge to balance the trade-off between the above properties in one *** we proposed a molecular design driven by dual interactions of acylsemicarbazide hydrogen bonding and Cu^(2+)-neocuproine coordination *** introducing the reversible multiple hydrogen bonds and strong coordination bonds,we successfully fabricated an extremely tough and self-healing *** elastomer can achieve an impressive top-notch toughness of 491 MJ/m^(3).Furthermore,it boasted rapid elastic restorability within 10 min and outstanding crack tolerance with high fracture energy(152.6kJ/m^(2)).Benefiting from the combination of dynamic interactions,the material was able to self-repair under 80℃conveniently and could be reprocessed to restore the exceptional mechanical properties.

关键词： Metal-ligand coordination Hydrogen bond Ultra-tough elastomer Self-healing

Earth-abundant Zn-dipyrrin chromophores for efficient CO2 photoreduction

在线全文

学校读者我要写书评

暂无评论

National Science Review 2024年第6期11卷 214-222页

作者： song Guo Fu-Gui Zeng xiao-Di Li Kai-Kai Chen ping Wang Tong-Bu Lu Zhi-Ming Zhang Institute for New Energy Materials and Low Carbon Technologies School of Materials Science& Engineering Tianjin University of Technology

The development of strong sensitizing and Earth-abundant antenna molecules is highly desirable for CO2reduction through artificial photosynthesis. Herein, a library of Zn–dipyrrin complexes（Z-1-Z-6） are rationally designed via precisely controlling their molecular configuration to optimize strong sensitizing Earth-abundant photosensitizers. Upon visible-light excitation, their special geometry enables intramolecular charge transfer to induce a charge-transfer state, which was first demonstrated to accept electrons from electron donors. The resulting long-lived reduced photosensitizer was confirmed to trigger consecutive intermolecular electron transfers for boosting CO2-to-CO conversion. Remarkably, the Earth-abundant catalytic system with Z-6 and Fe-catalyst exhibits outstanding performance with a turnover number of >20 000 and 29.7% quantum yield, representing excellent catalytic performance among the molecular catalytic systems and highly superior to that of noble-metal photosensitizer Ir（ppy）2（bpy）+under similar conditions. Experimental and theoretical investigations comprehensively unveil the structure–activity relationship, opening up a new horizon for the development of Earth-abundant strong sensitizing chromophores for boosting artificial photosynthesis.

关键词： Zn complex photocatalysis CO2 reduction charge transfer photosensitizer

Giant Magnetoresistance and Microstructure of Melt-Spun Cu_(70)Co_(30) Ribbons

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 1997年第2期14卷 148-150页

作者： song xiao-ping S.W.Mahon R.F.Cochrane B.J.Hickey M.A.Howson School of Materials and Department of Physics University of LeedsLeeds LS29JTUK School of Materials Xi'an Jiaotong UniversityXi'an 710049

This paper reports an investigation on the giant magnetoresistance and microstructure evolution in melt-spun Cu_(70)Co_(30) *** results show that the phase separation is inevitable in the course of quenching,leading to the formation of two types of fcc magnetic Co-rich particles but these do not appear to contribute to the magnetoresistance(MR).On annealing,a very fine distribution of Co-rich precipitates forms at temperatures above 573 K which are responsible for the high MR developed in this material.

关键词： alloy. Microstructure resistance

Plastic deformation behavior of a Cu-10Ta alloy under strong impact loading

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第2期32卷 368-382页

作者： ping song Jianghai Liu Wenbin Li Yiming Li Research Institute of Chemical Defense Academy of Military ScienceBeijing102205China Ministerial Key Laboratory of ZNDY Nanjing University of Science and TechnologyNanjing210094China

In this work,a Cu-10Ta alloy with a copper to tantalum mass ratio of 9:1 is prepared using powder metallurgy *** properties of the alloy,including density,microstructure,melting point,and constant-volume specific heat,are *** the split Hopkinson pressure bar(SHPB)and flyerplate impact experiments,the relationship between equivalent stress and equivalent plastic strain of the material is studied at temperatures of 298-823 K and under strain rates of 1×10^(-3)-5.2×10^(3)s^(-1),and the Hugoniot relationship at impact pressures of 1.46-17.25 GPa and impact velocities of 108-942 m/s is *** of the Cu-10Ta microstructure that occurs during high-strain-rate impact is *** indicate that the Cu-10Ta alloy possesses good thermal stability,and at ambient temperatures of up to 50%its melting point,stress softening of less than 15%of the initial strength is observed.A modified J-C constitutive model is employed to accurately predict the variation of yield strength with strain *** strong impact,the copper phase is identified as the primary source of plastic deformation in the Cu-10Ta alloy,while significant deformation of the high-strength tantalum particles is less ***,the longitudinal wave speed D is found to correlate linearly with the particle velocity u upon strong *** reveals that the sound speed and spallation strength of the alloy increase with increasing impact pressure.

关键词： Cu-10Ta SHPB Plastic deformation Flyer impact Hugoniot relationship

Silica-supported Polysiloxanes with Dithiacrown Ether Groups and Their Platinum Complexes

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 1992年第4期8卷 439-444页

作者： CHEN Yuan-yin, LU Xue-ran and song xiao-ping(Department of Chemistry, Wuhan University, Wuhan, 430072)

The present paper represents the syntheses of polypropyloxymethyldithia 15-crown-5 and 18-crown-6 supported on silica and their platinum complexes. The platinum complexes are effective catalysts for the hydrosilylation of olefins with triethoxysilane. The influences of temperature, amount of platinum complexes used and the nature of olefins used on the catalytic activity of the complexes are also investigated in this paper.

关键词： Functionalized polysiloxane Thiacrown ether Platinum complex Hydrosilyla-tion catalyst

Changes in posterior corneal elevation after small incision lenticule extraction for different myopic diopters

在线全文

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2024年第3期17卷 491-498页

作者： xiao-Tong Sun Yang Zhang xiao-Kun Mei Nan-Nan Zheng Ling-Zhi Niu xiao-Li Qu Ai-ping song Jian Zhuo Department of Ophthalmology the First Affiliated Hospital of Shandong First Medical UniversityShandong Provincial Qianfoshan HospitalJinan 250014Shandong ProvinceChina

●AIM:To study the changes and effect factors of posterior corneal surface after small incision lenticule extraction(SMILE)with different myopic diopters.●METHODS:Ninety eyes of 90 patients who underwent SMILE were included in this retrospective *** were allocated into three groups based on the preoperative spherical equivalent(SE):low myopia(SE≥-3.00 D),moderate myopia(-3.00 D>SE>-6.00 D)and high myopia(SE≤-6.00 D).Posterior corneal surfaces were measured by a Scheimpflug camera preoperatively and different postoperative times(1wk,1,3,6mo,and 1y).Posterior mean elevation(PME)at 25 predetermined points of 3 concentric circles(2-,4-,and 6-mm diameter)above the best fit sphere was analyzed.●RESULTS:All surgeries were completed uneventfully and no ectasia was found through the *** difference of myopia group was significant at the 2-mm ring at 1 and 3mo postoperatively(1mo:P=0.017;3mo:P=0.018).The effect of time onΔPME was statistically significant(2-mm ring:P=0.001;4-mm ring:P<0.001;6-mm ring:P<0.001).The effect of different corneal locations onΔPME was significant except 1wk postoperatively(1mo:P=0.000;3mo:P=0.000;6mo:P=0.001;1y:P=0.001).Posterior corneal stability was linearly correlated with SE,central corneal thickness,ablation depth,residual bed thickness,percent ablation depth and percent stromal bed thickness.●CONCLUSION:The posterior corneal surface changes dynamically after *** protrusion is observed on the posterior corneal surface in patients with different degrees of myopia within one year after *** has good stability,accuracy,safety and predictability.

关键词： myopia posterior corneal elevation corneal ectasia small incision lenticule extraction

Regulated polarization degree of upconversion luminescence and multiple anti-counterfeit applications

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第5期43卷 2172-2183页

作者： Dong-ping Wen ping Chen Yi Liang xiao-Ming Mo Cao-Feng Pan Center On Nanoenergy Research Guangxi Key Laboratory for Relativistic AstrophysicsSchool of Physical Science and TechnologyGuangxi UniversityNanning 530004China Key Laboratory of Micronano Energy and Sensor CAS Center for Excellence in NanoscienceBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 100140China

Polarization upconversion luminescence(PUCL)of lanthanide ions(Ln^(3+))has been widely used in single particle tracking,microfluidics detection,three-dimensional displays,and so ***,no effective strategy has been developed for modulating *** we report a strategy to regulate PUCL in Ho^(3+)-doped NaYF4single nanorods based on the number of upconversion *** constructing a multiphoton upconversion system for Ho^(3+),we regulate the degree of polarization(DOP)of PUCL from 0.590 for two-photon luminescence to 0.929 for three-photon upconversion luminescence(UCL).Furthermore,our strategy is verified from cross-relaxation between Ho^(3+)and Yb^(3+),excitation wavelength,excitation power density,and local site *** this regulation strategy of PUCL has also been achieved in Tm^(3+),with the DOP ranging from 0.233 for two-photon luminescence to 0.925 for four-photon UCL Besides,multi-dimensional anti-counterfeiting display has been explored with *** work provides an effective strategy for regulating PUCL and also provides more opportunities for the development of polarization display optical encoding,anti-counterfeiting,and integrated optical devices.

关键词： Polarization upconversion luminescence Degree of polarization Population density of excited state Number of upconversion photons Polarization anti-counterfeitingdisplay

Light-responsive Self-Immolative L-glutamic Acid-based Polyester Nanoparticles for Controlled Drug Release via Passerini Three-Component Polymerization

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第5期42卷 570-578,I0005页

作者： xiao-Fei Sun Xu Zhang Shu-ping song Ya-Qun Yao Yan Zhang Cheng-Liang Wang Jing-Jiang Sun Qing-Fu Wang Key Laboratory of Rubber-plastics Ministry of EducationSchool of Polymer Science and EngineeringQingdao University of Science and TechnologyQingdao266042China Qingdao Research Academy of Environmental Science Qingdao266012China

L-glutamic acid(LA)is a bio-based,non-toxic,environmentally friendly material derived from *** present study reports the application of Passerini three-component polymerization(P-3CP)for the straightforward preparation of LA-based light-responsive polyesters(PLTDs)under mild *** with molar masses up to 8500 g/mol and high yields exceeding 90%are *** chemical structures and light-responsive self-immolative behavior of PLTDs are comprehensively characterized by employing ultraviolet-visible(UV-Vis)spectroscopy,size exclusion chromatography(SEC),nuclear magnetic resonance(NMR)spectroscopy,and liquid chromatography mass spectrometry(LC-MS).Meanwhile,monodisperse PLTD-based doxorubicin-loaded nanoparticles(PLTD-DOX-NP)(size=193 nm,PDI=0.018)are formulated by nanoprecipitation *** light-induced depolymerization,the PLTD-DOX-NP undergoes rapid decomposition,resulting in a burst release of 80%cargo within 13 ***,according to biological toxicity tests,the PLTD-NP possesses adequate biosafety,both before and after ***,the incorporation of P-3CP with biorenewable LA-based monomer adheres to the principles of green chemistry,significantly simplifying the synthetic pathway of light-responsive polymers.

关键词： L-glutamic acid Passerini three-component polymerization Light-responsive Polyester Nanoparticles