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Synthesis and Properties of Reversible Disulfide Bond-based Self-healing Polyurethane with Triple Shape Memory Properties

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Chinese Journal of Polymer Science 2019年第11期37卷 1119-1129页

作者： Han Jia Kun Chang shu-ying Gu Department of Polymeric Materials School of Materials Science and Engineering Tongji University Shanghai 201804 China Key Laboratory of Advanced Civil Engineering Materials Ministry of Education Tongji University Shanghai 201804 China

A reversible disulfide bond-based self-healing polyurethane with triple shape memory properties was prepared by chain extending of random copolymer poly(lactide-co-caprolactone)(PCLA), hexamethylene diisocyanate (HDI), polytetrahydrofuran (PTMEG), and 4,4,-aminophenyl disulfide. The chemical structures were characterized using 1H nuclear magnetic resonance (^1H-NMR) spectroscopy, Fourier transform infrared spectroscopy (FTIR), and gel permeation chromatography (GPC). The thermal properties, selfhealing properties, triple-shape memory effect, and quantitative shape memory response were evaluated by differential scanning calorimetry (DSC), tensile tests, two-step programming process thermal mechanical experiments, and subsequent progressive thermal recovery. The self-healing mechanism and procedures were investigated using polarizing optical microscopy (POM) and an optical profiler. It was concluded that self-healing properties (up to 60%) and triple-shape memory properties around 35 and 50℃(with shape fixation ratios of 94.3% and 98.3%, shape recovery ratios of 76.6% and 85.1%, respectively) were integrated to the shape memory polyurethane. As-prepared polyurethane is expected to have potential applications in multi-shape coatings, films, and step-by-step deploying structures.

关键词： Self-healing Reversible disulfide bond Triple shape memory Polyurethane

Enhanced methanol oxidation activity of Au@Pd nanoparticles supported on MWCNTs functionalized by MB under ultraviolet irradiation

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Rare Metals 2015年第1期34卷 12-16页

作者： Ming-Li Xu Xi-Kun yang ying-Jie Zhang shu-Biao Xia Peng Dong Guo-Tao yang Faculty of Science Kunming University of Science and Technology Research Center for Analysis and Measurement Kunming University of Science and Technology Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology

A successful approach to assemble Au core Pd shell （Au@Pd） nanoparticles on the surface of multi-walled carbon nanotubes functionalized by methylene blue （MB）（Au@Pd/fuv-MWCNTs） was reported. In this method, MWCNTs were functionalized under ultraviolet irradiation. UV-Vis analysis and high-angle annular dark-field trans- mission electron microscope （HAADF-TEM） image prove that core-shell structure of Au@Pd nanoparticles forms. TEM results indicate that Au@Pd nanoparticles （ - 5.2 nm） are well-dispersed on the surface of fuv-MWCNTs. X-ray photoelectron spectroscopy （XPS） reveals that ultraviolet irradiation can promote the interaction between Au@Pd nanoparticles and the functional groups on the surface of MWCNTs. Cyclic voltammograms （CV）, chronoampero- grams （CA）, and electrochemical impedance spectroscopy （EIS） results demonstrate that the Au@Pd/fuv-MWCNTs catalysts show excellent electrocatalytic performance for methanol oxidation in alkaline media. The catalytic activity of the Au@Pd/fuv-MWCNTs is ~ 2 times higher than that of the commercial Pd/C catalysts. This is mostly attributed to that ultraviolet irradiation can make the moieties of MB provide a uniform surface with active and anchoring sites, and improves the functional effect of MB on the surface of MWCNTs. Especially, ultraviolet irradiation modifies electronic structure of Pd and is beneficial for the enhance- ment of catalytic activity.

关键词： Au@Pd core-shell nanoparticle Multi-walledcarbon nanotube Methylene blue Electrocatalyst Methanol oxidation Ultraviolet irradiation

Representations of Graph States with Neural Networks

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Acta Mathematica Sinica,English Series 2023年第4期39卷 685-694页

作者： ying yang School of Mathematics and Information Technology Yuncheng UniversityYuncheng 044000P.R.China

Quantum many-body problem(QMBP)has become a hot topic in high energy physics and condensed matter *** the exponential increasing of the dimension of the Hilbert space,it becomes a big challenge to solve the QMBP even with the most powerful *** the rapid development of machine learning,artificial neural networks provide a powerful tool to represent or approximate quantum many-body *** this paper,we aim to construct explicitly the neural network representations of graph states,without stochastic optimization of the network *** method shows constructively that all graph states can be represented precisely by proper neural networks originated from[Science,355,602(2017)]and formulated in[***.,63,210312(2020)].

关键词： Graph state neural network quantum state representation

Atmospheric reductive catalytic fractionation of lignocellulose integrated with one-pot catalytic conversion of carbohydrate yielding valuable lignin monomers and platform chemicals from corn straw

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Green Energy & Environment 2025年第1期10卷 161-172页

作者： Meng-ying Liu Zhe-Hui Zhang Xue-Qi Wang Qian Sun Chen Zhang Yu Li Zhuohua Sun Katalin Barta Feng Peng Tong-Qi Yuan State Key Laboratory of Efficient Production of Forest Resources Beijing Forestry UniversityBeijing100083China Beijing Key Laboratory of Lignocellulosic Chemistry Beijing Forestry UniversityBeijing100083China Department of Chemistry Organic and Bioorganic ChemistryUniversity of GrazHeinrichstrasse 28/II8010 GrazAustria

Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent ***,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps *** key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney Ni catalyst and high boiling point ethylene *** utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling *** the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%.

关键词： Atmospheric reductive catalytic fractionation Corn straw Ethylene glycol Raney Ni 5-Methoxymethylfurfural

Host susceptibility to persistent hepatitis B virus infection

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World Journal of Gastroenterology 2006年第30期12卷 4788-4793页

作者： ying-Li He ying-Ren Zhao shu-Lin Zhang shu-Mei Lin Department of Infectious Diseases the First Hospital of Xi'an Jiaotong University Xi'an 710061 Shaanxi Province China

Genetic epidemiology researches such as twin studies, family-clustering of hepatitis B virus （HBV） infection studies and ethnic difference studies have provided the evidence that host genetic factors play an important role in determining the outcome of HBV infection. The opening questions include which human genes are important in infection and how to find them. Though a number of studies have sought genetic associations between HBV infection/persistence and gene polymorphisms, the candidate gene-based approach is clearly inadequate to fully explain the genetic basis of the disease. With the advent of new genetic markers and automated genotyping, genetic mapping can be conducted extremely rapid. This approach has been successful in some infectious diseases. Linkage analysis can find host genes susceptible to HBV and is of great clinical importance.

关键词： Hepatitis B virus Susceptibility Association study Linkage study

Phenolic Profiles and Antioxidant Activity of Buckwheat (Fagopyrum esculentum Mench and Fagopyrum tartaricum L. Gaerth) Hulls, Brans and Flours

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Journal of Integrative Agriculture 2013年第9期12卷 1684-1693页

作者： LI Fu-hua YUAN Ya yang Xiao-lan TAO shu-ying MING Jian College of Food Science Southwest University Key Laboratory of Food Processing & Technology of Chongqing Laboratory of Quality & Safety Risk Assessment for Agro-Products on Storage and Presevation Mimnistry of Agriculture

The extracts from hulls, brans and flours of Fagopyrum esculentum M6ench （FEM, three varieties） and Fagopyrum tartaricum L. Gaerth （FTG, seven varieties） were screened for free and bound phenolic content or total phenolic content （TPC）, as well as 1,1 diphenyl-2-picryl hydrazyl （DPPH） free radical scavenging activity and reducing power. Free phenolics were predominant in buckwheat hulls, brans and flours. FEM hulls extract exhibited the highest reducing power and DPPH free radical scavenging activity with the average ECs0 84.54 μg mL^-1 and IC50 11.54 μg mL^-1 respectively, FTG brans extract had the highest average TPC （24.87 mg GAE g^-1 DW）, and FEM flours extract showed the lowest TPC, reducing power and radical scavenging activity. Furthermore, the correlations among TPC, DPPH free radical scavenging activity and reducing power of all the samples were investigated. The rank correlation coefficient （rs） between reducing power and DPPH free radical scavenging activity of buckwheat hulls, between TPC and DPPH free radical scavenging activity of buckwheat flours were 0.76 and 0.79, respectively （P〈0.05）. However, there is no significant correlation between the remaining indexes of hulls and flours, as well as the ten buckwheat brans. This result indicated that some non-phenolic compounds also contributed to the total antioxidant activity in hulls, brans and flours of buckwheats. This study demonstrated that buckwheat hulls and brans, rather than flours, are good source of antioxidants.

关键词： Fagopyrum esculentum MSench Fagopyrum tartaricum L. Gaerth phenolic content antioxidative activity,buckwheat correlation analysis

Detecting surface freeze/thaw states in Northeast China with passive microwave data using an improved standard deviation method

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Advances in Climate Change Research 2023年第2期14卷 190-199页

作者： Hao-Ran MAN yang XIAO shu-ying ZANG Miao LI Xing-Feng DONG Heilongjiang Province Key Laboratory of Geographical Environment Monitoring and Spatial Information Service in Cold Regions Harbin Normal UniversityHarbin 150025China Heilongjiang Province Collaborative Innovation Center of Cold Region Ecological Safety Harbin 150025China

Passive microwave remote sensing datasets are widely used to observe surface freeze/thaw(F/T)***,current algorithms are highly affected by snow cover and complex land cover types,compromising their ***,this study proposes an improved algorithm for daytime detection of diurnal F/T states by using Advanced Microwave Scanning Radiometer 2 *** the daytime F/T discrimination algorithm,a microwave spectral gradient index is applied to divide the surface into snow-covered and snow-free *** the snow-free area,the surface temperature index is optimised to improve the accuracy of the standard deviation method(SDM)in evaluating the accuracy of the F/T *** the nighttime dataset,the microwave standard deviation index difference values between day and night are used to detect the F/T states based on the daytime *** accuracy of the improved algorithm reaches 88.6%and 84.5%in the daytime and at nighttime,*** with the SDM,the accuracy is improved by 10.2%in the daytime and 5.4%at *** results demonstrate that the proposed model is able to effectively distinguish the F/T states of snow-covered *** the surface temperature index can significantly improve the accuracy of the *** results reveal that the proposed surface F/T detection algorithm can be applied to regions with complex land cover types.

关键词： Microwave remote sensing Surface F/T algorithm improvement Seasonal snow areas Classification Northeast China

EM Scattering from Conducting Flat Plates Coated with Thin RAM

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Wuhan University Journal of Natural Sciences 2002年第2期7卷 185-188页

作者： yang He-lin Xia ying-qing Lu shu Liu Wu Department of Physics Central China Normal UniversityWuhan 430079China School of Electronic Information Wuhan UniversityWuhan 430072China

According to the equivalence principles, high frequency approximation and boundary conditions, a method has been developed to deal with the EM scattering by a rectangular conducting flat plate coated with uniaxial anisotropic radar absorbing material (RAM). The simple and effective method is available to the system of RCS prediction in which the large complex targets modeled by facets and wedges. Numerical results show some properties of EM scattering by conducting plate coated with thin uniaxial anisotropic RAM.

关键词： EM scattering equivalence principles radar absorbing material

“Zero‑Strain” NiNb_(2)O_(6) Fibers for All‑Climate Lithium Storage

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Nano-Micro Letters 2025年第1期17卷 348-360页

作者： Yan Zhao Qiang Yuan Liting yang Guisheng Liang Yifeng Cheng Limin Wu Chunfu Lin Renchao Che College of Physics Donghua UniversityShanghai 201620People’s Republic of China School of Materials Science and Engineering Institute of Materials for Energy and EnvironmentQingdao UniversityQingdao 266071People’s Republic of China Laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438People’s Republic of China Zhejiang Laboratory Hangzhou 311100People’s Republic of China Inner Mongolia University Hohhot 010021People’s Republic of China

Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte ***,their moderate unit-cellvolume expansion(generally 5%–10%)during Li^(+)storage causes unsatisfactory long-term ***,“zero-strain”NiNb_(2)O_(6) fibers are explored as a new anode material with comprehensively good electrochemical *** Li^(+)storage,the expansion of electrochemical inactive NiO_(6) octahedra almost fully offsets the shrinkage of active NbO_(6) octahedra through reversible O *** superior volume-accommodation capability of the NiO_(6) layers guarantees the“zero-strain”behavior of NiNb_(2)O_(6) in a broad temperature range(0.53%//0.51%//0.74%at 25//−10//60℃),leading to the excellent cyclability of the NiNb_(2)O_(6) fibers(92.8%//99.2%//91.1%capacity retention after 1000//2000//1000 cycles at 10C and 25//−10//60℃).This NiNb_(2)O_(6) material further exhibits a large reversible capacity(300//184//318 mAh g−1 at 0.1C and 25//−10//60℃)and outstanding rate performance(10 to 0.5C capacity percentage of 64.3%//50.0%//65.4%at 25//−10//60℃).Therefore,the NiNb_(2)O_(6) fibers are especially suitable for large-capacity,fast-charging,long-life,and all-climate lithium-ion batteries.

关键词： NiNb_(2)O_(6)porous fiber “Zero-strain”mechanism Electrochemical property Harsh-temperature operation Operando characterization