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Sol-gel preparation and phosphorescence property of Mn^(2+)-doped zinc boro-silicate glass thin films

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Rare Metals 2011年第3期30卷 298-303页

作者： li fengfeng ZHANG Mingxi HOU Guiqin SHEN Yi liU Zhigang li Hongsheng College of light Industry Hebei Polytechnic University Tangshan 063000 China Key Laboratory for Inorganic Non-metallic Materialogy of Hebei Province College of Materials Science and Engineering Hebei Polytechnic University Tangshan 063009 China

Mn2＋-doped zinc borosilicate （ZBSM） glass thin films were first synthesized by sol-gel method. In the experiment, a thin gel film was depos-ited onto quartz glass substrates by dip-coating method and then heat-treated to form a Mn2＋-doped zinc borosilicate glass thin film. Long lasting phosphorescence （LLP） and photo-stimulated long lasting phosphorescence （PSLLP） were found in the film sample. According to fluorescence spectra, LLP emission spectra, and PSLLP emission spectra, both LLP and PSLLP emissions are attributed to the energy level transition of 4Eg→4A1g from Mn2＋. Both the phosphorescence intensity decay curves contain a fast decay component and another slow decay one. The thermoluminescence （TL） spectra show that the sample has two kinds of traps at least and their energy level values are about 0.8 eV and 1.02 eV, which could be estimated by the Randall and Willcins formula. The infrared absorption spectra （IR） consist of characteristic vi-bration bands of Si-O-Si, Si-O-Zn, B-O in [BO3], B-O group, and Zn-O in [ZnO4]. Moreover, image storage and logical operation of the ZBSM film were carried out successfully through an experiment analogues of optical storage.

关键词： thin films borosilicate glass zinc borosilicate manganese doping sol-gel process phosphorescence

Shape recovery properties and load-carrying capacity of a 4D printed thick-walled kirigami-inspired honeycomb structure

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Bio-Design and Manufacturing 2023年第2期6卷 189-203页

作者： Chengbin Yue Wei Zhao fengfeng li liwu liu Yanju liu Jinsong Leng Department of Astronautical Science and Mechanics Harbin Institute of TechnologyHarbin 150001China Center for Composite Materials and Structure Harbin Institute of TechnologyHarbin 150080China

Kirigami arts have provided a more promising method for building multiscale structures,which can shape two-dimensional(2D)sheets into three-dimensional(3D)configurations by cutting and ***,we first carried out a theoretical analysis of the mechanical properties of 2D honeycomb lattice structures and experimental verification combined with finite element(FE)***,a series of thick-walled 3D kirigami-inspired honeycomb(TW3KH)structures with different mechanical properties were designed and fabricated on the exploration and optimization of geometric parameters of 2D honeycomb *** investigations of folding feasibility,self-expansion,and self-folding performance experimentally showed that our designed four-dimensional(4D)printing structure had good programmability and shape memory capability and a large volume change ratio during shape ***,research on its compression deformation behavior found that the TW3KH structures can recover load-bearing capacity very well when the angle is ***,these TW3KH structures have great advantages in space-saving smart load-bearing equipment.

关键词： Shape memory 4D printing Kirigami arts Pattern transformation

Theoretical Analysis of the Buckling Behaviors of Inhomogeneous Shape Memory Polymer Composite Laminates Considering Prestrains

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Acta Mechanica Solida Sinica 2024年第2期37卷 271-284页

作者： Hanxing Zhao Pengyu Cao fengfeng li Xin Lan liwu liu Yanju liu Jinsong Leng Centre of Composite Materials and Structures Harbin Institute of Technology(HIT)Harbin150080China Department of Astronautical Science and Mechanics Harbin Institute of Technology(HIT)Harbin150001China

The mismatch in thermal expansion coefficients between the fiber-rich and resin-rich regions of a shape memory polymer composite(SMPC)laminate,along with the residual strain during SMPC fabrication,results in buckling deformation of the inhomogeneous *** paper presents a macroscopic model for buckling of an inhomogeneous SMPC laminate under initial biaxial *** linear and nonlinear buckling analyses are carried out using the energy *** influences of prestrain biaxiality,temperature,and ply angle on the buckling wavelength,critical buckling prestrain,and buckling amplitude are *** results demonstrate that the critical buckling wavelength of the SMPC laminate is independent of the prestrain,while the amplitude is almost independent of *** addition,the optimal fiber stacking configuration with the maximum critical buckling prestrains of inhomogeneous SMPC laminates is determined by a genetic algorithm.

关键词： Shape memory polymer composite Buckling behavior Inhomogeneous laminate Biaxial prestrains

Recent advances in nickel-based catalysts in eCO_(2)RR for carbon neutrality

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Carbon Energy 2024年第2期6卷 61-91页

作者： Weikang Peng fengfeng li Shuyi Kong Chenxi Guo Haotian Wu Jiacheng Wang Yi Shen Xianguang Meng Mingxi Zhang Hebei Key Laboratory of Inorganic Nonmetallic Materials School of Materials Science and EngineeringNorth China University of Science and TechnologyTangshanHebeiChina Hebei Iron and Steel Laboratory North China University of Science and TechnologyTangshanChina State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghaiChina School of Materials Science and Engineering Taizhou UniversityZhejiangChina

The excessive use of nonrenewable energy has brought about serious greenhouse *** CO_(2) into high-value-added chemicals is undoubtedly the best choice to solve energy *** to the excellent cost-effectiveness and dramatic catalytic performance,nickel-based catalysts have been considered as the most promising candidates for the electrocatalytic CO_(2) reduction reaction(eCO_(2)RR).In this work,the electrocatalytic reduction mechanism of CO_(2) over Ni-based materials is *** strategies to improve the eCO_(2)RR performance are ***,the research on Ni-based materials for syngas generation is briefly ***,the prospects of nickel-based materials in the eCO_(2)RR are provided with the hope of improving transition-metal-based electrocatalysts for eCO_(2)RR in the future.

关键词： carbon energy carbon neutrality CO_(2)reduction electrocatalysis nickel-based materials

Preliminary design and analysis of a cubic deployable support structure based on shape memory polymer composite

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International Journal of Smart and Nano Materials 2016年第2期7卷 106-118页

作者： fengfeng li liwu liu Xin Lan Xiaojun Zhou Wenfeng Bian Yanju liu Jinsong Leng Department of Astronautical Science and Mechanics Harbin Institute of Technology(HIT)HarbinPeople’s Republic of China Centre for Composite Materials Science Park of Harbin Institute of Technology(HIT)HarbinPeople’s Republic of China Department of Civil Engineering Harbin Institute of TechnologyWeihaiChina

The deployable structures based on shape memory polymer com-posites(SMPCs)have been developed for its unique properties,such as high reliability,low-cost,lightweight,and self-deployment without complex mechanical devices compared with traditional deployable *** order to increase the inflatable structure system’s robustness and light the weight of it,a cubic deployable support structure based on SMPC is designed and analyzed *** cubic deployable support structure based on SMPC consists of four dependent spatial cages,each spatial cage is composed of 12 three-longeron SMPC truss booms and end *** shape recovery of arc-shaped deployable laminates drive the three-longeron SMPC truss booms to unfold,thus realize the expansion of the deployable support *** concept and operation of the cubic deployable support structure are described in detail.A series of experiments are performed on the three-longeron deployable laminates unit and the simplified cubic deployable support structure to investigate the shape recovery behavior in the deployment *** indicate that the cubic deployable support structure has a high deployment-tgo-stowage volume ratio and can achieve self-deployment,package,and deploy without complex mechanical devices.

关键词： Shape memory polymer composites deployable structure shape recovery experiment

Visible light promoted aerobic selective photo-oxidation of cyclohexene on LaCo_(x)Cu_(1−x)O_(3) catalyst

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Nano Research 2024年第8期17卷 6940-6950页

作者： Xu Guo liru Song Wenyu Wang fengfeng li Minh Ngoc Ha Jun Tang Qiang ling Ping Cui Qingping Ke College of Chemistry and Chemical Engineering Anhui University of TechnologyMaanshan 243000China VNU Key Laboratory of Advanced Material for Green Growth Faculty of ChemistryUniversity of ScienceVietnam National UniversityHanoi 100000Vietnam

Heterogeneously catalyzed liquid oxidation of olefins with O_(2) provides an alternative way for synthesizing high-value added ***,we report a straightforward urea-redox and sol-gel process for synthesizing LaCo_(x)Cu_(1−x)O_(3) for aerobic photooxidation of *** research highlights a marked increase in the proportions of Co^(2+) and Cu+species in a low chemical state,as well as enhanced visible light absorption through this *** investigations suggest that the catalytic process,particularly with LaCo_(0.7)Cu_(0.3)O_(3),involves a radical pathway mediated by reactive oxygen *** presence of Cu+/Co^(2+) species and surface oxygen vacancies is proposed to boost O_(2) adsorption and activation on the catalyst,facilitating the formation of ***,Cu^(2+)/Co^(3+) species are thought to aid in generating cyclohexenederived radical *** efficient aerobic oxidation of cyclohexene on LaCo_(0.7)Cu_(0.3)O_(3) catalyst relies on the formation of reactive oxygen species and carbon radicals,facilitated by its strong visible light *** achieves a cyclohexene conversion of 89.4% and selectivity to cyclohex-2-ene-1-one of 72.2%,along with stable recyclability after six *** creation of nano-structured LaCo_(x)Cu_(1−x)O_(3) through the urea-redox and sol-gel process offers a promising avenue for the development of highly efficient catalysts for the aerobic photo-oxidation of cyclohexene to cyclohex-2-ene-1-one in the future.

关键词： perovskite oxide photocatalysis oxidation cyclohexene LaCoCuO_(3) cyclohex-2-ene-1-one

Revealing efficient catalytic performance of N-CuO_(x) for aerobic oxidative coupling of aliphatic alkynes:A Langmuir-Hinshelwood reaction mechanism

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Nano Research 2022年第7期15卷 6076-6083页

作者： Jun Tang Bowen Jiao Wei Chen Fei Ruan fengfeng li Peixin Cui Chao Wan Minh Ngoc Ha Van Noi Nguyen Qingping Ke College of Chemistry and Chemical Engineering Anhui University of TechnologyMaanshan 243002China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil Sciencethe Chinese Academy of SciencesNanjing 210008China VNU Key Laboratory of Advanced Material for Green Growth VNU University of ScienceVietnam National UniversityHanoi 100000Vietnam

O_(x)idative couplings of aliphatic alkynes are crucial for the production of naturally occurring 1,*** we report the novel approach for effective synthesis of unsaturated coordinated N doped copper oxides(N-CuO_(x))catalyst,and uncover that N-CuO_(x) catalyst as an additive-free and cost-effective heterogeneous catalyst has highly catalytic performance for directly oxidative coupling of aliphatic *** key to achieve efficient oxidative coupling of aliphatic alkynes is the synergistic effect of N species and uncoordinated O/Cu species caused by N dopants,which undergoes the Langmuir–Hinshelwood reaction *** N-CuO_(x) catalyst displays~89.1%yield for hexadeca-7,9-diyne under mild conditions and stable reusability(5 cycles),showing significant advances compared with the traditionally copper *** findings highlight the heteroatom dopants that provide a new methodology for designing efficient copper catalysts in synthesis of naturally occurring 1,3-diynes.

关键词： N doped copper oxides(N-CuO_(x)) straight chain alkynes homo-coupling additive-free 1,3-diynes

Transformation mechanism of muddy carbonate rock by the coupling of bioturbation and diagenesis:A case study of the Cretaceous of the Mesopotamia Basin in the Middle East

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Petroleum Exploration and Development 2021年第6期48卷 1367-1382页

作者： YE Yu li fengfeng SONG Xinmin GUO Rui Research Institute of Petroleum Exploration&Development PetroChinaBeijing 100083China CNPC Engineering Technology R&D Company limited Beijing 102206China

The transformation mechanism of muddy carbonate rock by the coupling of bioturbation and diagenesis was stud-ied based on core,cast thin section and physical property data of Cretaceous strata in the Mesopotamia Basin,the Middle *** are 3 ways of biological transformation of rocks:(1)The living creatures transformed formations mechanically to make the rocks looser and intergranular pores increase.(2)After formation,burrows were backfilled with coarse-grained debris,and then unsaturated fluid infiltrated into the burrows during the penecontemporaneous period,resulting in dissolution.(3)Chemical alteration occurred in abandoned burrows and dolomitization produced a large number of intercrystalline ***·coupling of bioturbation and dissolution occurred mainly in the penecontemporaneous phase,and was controlled by rock type,sea level decline,burrow abundance,infillings,and water environment *** the burrows had better physical properties than the matrix,unsaturated fluid preferentially migrated along the burrows,leading to dissolution and expansion of the burrows first and then dissolution of the *** coupling of bioturbation and dolomitization occurred mainly in the burial *** rich organic matter and reducing bacteria in the burrow provided material basis,reducing conditions and alkaline envi-ronment for *** metasomatism in the penecontemporaneous period had little effect on the physical properties of the *** the burrows were se parated from the deposition interface,equimolar metasomatism occurred in the burrows in a closed environment,forming euhedral fine-crystalline dolomite with intercrystalline *** transformation degree of bioturbation to muddy carbonate reservoir depends on rock type,density,connectivity,infillings and structure of the *** the increase of the carbonate mud content,the im provement to rock physical properties by bioturbation be-comes more *** the burrows are filled with co

关键词： bioturbation muddy carbonate rocks Mesopotamia Basin Cretaceous diagenesis dissolution dolomitization

Anthelmintics nitazoxanide protects against experimental hyperlipidemia and hepatic steatosis in hamsters and mice

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Acta Pharmaceutica Sinica B 2022年第3期12卷 1322-1338页

作者： fengfeng li Man Jiang Minghui Ma Xuyang Chen Yidan Zhang Yixin Zhang Yuanyuan Yu Yunfeng Cui Jiahui Chen Hui Zhao Zhijie Sun Deli Dong Department of Pharmacology(the State-Province Key Laboratories of Biomedicine-Pharmaceutics of China Key Laboratory of Cardiovascular ResearchMinistry of Education)College of PharmacyHarbin Medical UniversityHarbin 150086China Translational Medicine Research and Cooperation Center of Northern China Heilongjiang Academy of Medical SciencesHarbin Medical UniversityHarbin 150086China Department of Pharmacology China Pharmaceutical UniversityNanjing 211198China

lipid metabolism disorders contribute to hyperlipidemia and hepatic *** is ideal to develop drugs simultaneous improving both hyperlipidemia and hepatic *** is an FDA-approved oral antiprotozoal drug with excellent pharmacokinetic and safety *** found that nitazoxanide and its metabolite tizoxanide induced mild mitochondrial uncoupling and subsequently activated AMPK in Hep G2 *** administration of nitazoxanide inhibited high-fat diet(HFD)-induced increases of liver weight,blood and liver lipids,and ameliorated HFD-induced renal lipid accumulation in *** significantly improved HFD-induced histopathologic changes of hamster *** the hamsters with pre-existing hyperlipidemia and hepatic steatosis,nitazoxanide also showed therapeutic *** administration of nitazoxanide improved HFD-induced hepatic steatosis in C57BL/6J mice and western diet(WD)-induced hepatic steatosis in Apoe-/-*** present study suggests that repurposing nitazoxanide as a drug for hyperlipidemia and hepatic steatosis treatment is promising.

关键词： Nitazoxanide Tizoxanide Hyperlipidemia Hepatic steatosis AMPK Autophagy SQSTM1/P62 Mitochondrial uncoupling