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Homogenization of a Nonlinear Degenerate Parabolic Differential Equation

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Acta Mathematica Sinica,English Series 2013年第7期29卷 1429-1436页

作者： Hai Tao CAO Xing ye yue Department of Mathematics and Physics Changzhou Campus Hohai University Department of Mathematics Soochow University

This paper is devoted to the homogenization of a nonlinear degenerate parabolic problemwith Dirichlet boundary condition. Here the operator D（y, s, △s） is periodic in y and degenerated in △s. In the paper, under the two-scale convergence theory, we obtain the limit equation as ∈ → 0 and also prove the corrector results of △u^∈ to strong convergence.

关键词： Nonlinear degenerate parabolic equation homogenization two-scale convergence

Synthesis and Characterization of pH-Responsive Block Copolymers with Primary Amine Groups

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Chemical Research in Chinese Universities 2013年第2期29卷 389-395页

作者： wang Hong ZHU yue-jun REN Xiao-na ZHANG Hong TAN ye-bang Key Laboratory of Special Functional Aggregated Materials Ministry of Education School of Chemistry and Chemical Engineering Shandong University Jinan 250100 P. R. China State Key Laboratory of Offshore Oil Exploitation Technology Research Department of Research Center China National Offshore Oil Corporation Beijing 100027 P R. China

A new pH-responsive block copolymer, methoxy poly（ethylene glycol）-b-poly[5-methacrylamido- pentylamine hydrochloride]（mPEG-b-PMAAPA） was synthesized and characterized in this paper. The monomer 5-methacrylamido-pentylamine hydrochloride（MAAPA） and the macroinitiator（mPEG-ACVA） were synthesized, re- spectively, and mPEG-b-PMAAPA was then obtained by free radical polymerization. The structure and molecular weight of mPEG-b-PMAAPA were cont]rmed by hydrogen nuclear magnetic resonance（~H NMR） spectroscopy and gel permeation chromatography with multiangle laser light scattering（GPC-MALLS） measurements. At a low pH, it is hydrophilic due to the protonation of the primary amine groups. With increasing pH value, deprotonation occurs and the hydrophobicity of PMAAPA block increases. This molecular feature leads to interesting aggregation behavior of mPEG-b-PMAAPA in aqueous solutions at different pH values as revealed by dynamic light scattering（DLS） measurements, transmission electron microscopy（TEM） observations and resonance light scattering（RLS） measure- ments.

关键词： Block copolymer Polyamine pH-Responsive Water soluble copolymer

Orientational growth behavior and mechanism of delta(δ)phase precipitation in cold-rolled Inconel 718 alloy during heat treatment

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Journal of Iron and Steel Research International 2024年第1期31卷 264-274页

作者： Neng-yong ye Guang-liang Zhang Tian-yue Huang Ming Cheng Shi-hong Zhang Lei wang School of Materials Science&Engineering Taizhou UniversityTaizhou318000ZhejiangChina Institute of Metal Research Chinese Academy of SciencesShenyang110016LiaoningChina

Due to the important role ofδphase's quantity and morphology in the mechanical and fatigue properties of Inconel 718 alloy and its components,it is necessary to renew insights into the effect of cold deformation on theδphase precipitation,especially on the morphology ***,the nucleation and growth behavior ofδphase in cold-rolled Inconel 718 alloy during aging were *** results show that the precipitation rate and volume fraction ofδphase increase with increasing the cold rolling reduction from 10%to 50%.The volume fraction ofδphase reaches equilibrium after 5 h,remaining at 5.98%,6.52%,and 6.79%under different rolling reductions(10%,30%,and 50%),*** nucleation ofδphase mainly occurs on different sites(grain boundaries,new twin boundaries and old twin boundaries)under 10%rolling reduction,whileδphase mainly nucleates on the new grain boundaries of static recrystallization due to 50%rolling *** the growth ofδphase undergoes a process of alternate orientation growth from spherical(nucleation)→short rod(longitudinal orientation growth)→short rod(radial orientation growth)→dynamic *** 10%rolling reduction,δphase tends to grow into the matrix,while under 50%rolling reduction,the orientation grows faster and is easily affected by the grain boundary curvature.

关键词： Inconel 718 alloy Cold rolling δphase Orientation growth Morphology evolution

MoS_(2)Lubricate‑Toughened MXene/ANF Composites for Multifunctional Electromagnetic Interference Shielding

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Nano-Micro Letters 2025年第2期17卷 358-371页

作者： Jiaen wang Wei Ming Longfu Chen Tianliang Song Moxi yele Hao Zhang Long Yang Gegen Sarula Benliang Liang Luting Yan Guangsheng wang School of Physical Science and Engineering Beijing Jiaotong UniversityBeijing 100044People’s Republic of China Key Laboratory of Bio‑Inspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191People’s Republic of China

The design and fabrication of high toughness electromagnetic interference(EMI)shielding composite films with diminished reflection are an imperative task to solve electromagnetic pollution *** MXene/ANF(aramid nanofibers)–MoS_(2)composite films with nacre-like layered structure here are fabricated after the introduction of MoS_(2)into binary MXene/ANF composite *** introduction of MoS_(2)fulfills an impressive“kill three birds with one stone”improvement effect:lubrication toughening mechanical performance,reduction in secondary reflection pollution of electromagnetic wave,and improvement in the performance of photothermal *** the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 50:50),the strain to failure and tensile strength increase from 22.1±1.7%and 105.7±6.4 MPa and to 25.8±0.7%and 167.3±9.1 MPa,*** toughness elevates from 13.0±4.1 to 26.3±0.8 MJ m^(−3)(~102.3%)*** the reflection shielding effectiveness(SE_(R))of MXene/ANF(mass ratio of 50:50)decreases~10.8%.EMI shielding effectiveness(EMI SE)elevates to 41.0 dB(8.2–12.4 GHz);After the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 60:40),the strain to failure increases from 18.3±1.9%to 28.1±0.7%(~53.5%),the SE_(R)decreases~22.2%,and the corresponding EMI SE is 43.9 *** MoS_(2)also leads to a more efficient photothermal conversion performance(~45 to~55℃).Additionally,MXene/ANF–MoS_(2)composite films exhibit excellent electric heating performance,quick temperature elevation(15 s),excellent cycle stability(2,2.5,and 3 V),and long-term stability(2520 s).Combining with excellent mechanical performance with high MXene content,electric heating performance,and photothermal conversion performance,EMI shielding ternary MXene/ANF–MoS_(2)composite films could be applied in many industrial *** work broadens how to achieve a balance between mechanical properties and versatility of composites in the case of high-function fillers.

关键词： MXene-MoS_(2) Lubrication toughening EMI shielding Photothermal conversion Electric heating performance

Regulation of graphdiyne-based nanozymes with enhanced oxidaselike activity by cobalt and nitrogen codoping

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Nano Research 2025年第1期18卷 21-29页

作者： Jiali Liu Xiaoli wang Yongfu Lian Xue wang Xiuxiu wang Xingfa Gao Baoyun Sun Xihong Guo CAS Key Laboratory for Biomedical Effects of Nanomaterial&Nanosafety Institute of High Energy PhysicsChinese Academy of ScienceBeijing 100049China Key Laboratory of Functional Inorganic Material Chemistry Ministry of EducationSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080China Laboratory of Theoretical and Computational Nanoscience National Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The development of nanozymes with excellent intrinsic oxidase-like activity and specificity has received increasing ***(GDY)could be a promising choice for designing nanozymes with enhanced oxidase(OXD)-like activity due to its unique structure and ***,Co-N-GDY with high OXD activity but no peroxidase(POD)activity was synthesized by codoping of cobalt(Co)and nitrogen(N)into GDY and compared with other GDY-based nanozymes(including GDY,Co-GDY,and N-GDY).Upon analyzing the doping effect of Co and N on the OXD-like and POD-like activities,we found that the combination of Co and N in GDY played a significant role in enhancing the OXD-like activity,and even reversed the POD-like activity of N-GDY to OXD-like activity of *** electrochemical experiment and the theoretical calculations provided an explanation for the mechanism and showed that the activity was closely linked to the reduction ability of O_(2) or H_(2)O_(2) on the nanozyme substrates,which was determined by the ratedetermining step of the catalytic reaction.

关键词： nanozymes oxidase-like activity graphdiyne heteroatom doping regulation

Confined growth of ZIF-8 in dendritic mesoporous organosilica nanoparticles as bioregulators for enhanced mRNA delivery in vivo

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National Science Review 2021年第8期8卷 198-207页

作者： yue wang Hao Song Chao Liu ye Zhang yueqi Kong Jie Tang Yannan Yang Chengzhong Yu Australian Institute for Bioengineering and Nanotechnology The University of Queensland School of Chemistry and Molecular Engineering East China Normal University

Zeolitic imidazolate framework-8(ZIF-8) and its composites have diverse applications. However,ZIF-8-based nanocomposites are mainly used as carriers in biomolecular delivery, with the functions of metal ions and ligands rarely used to modulate the biofunctions. In this work, dendritic mesoporous organosilica nanoparticles(DMONs) with tetrasulfide bond were used to confine ZIF-8 growth partially inside mesopores as a novel nanocomposite for m RNA delivery. Each component in the resultant DMONs-ZIF-8 contributed to m RNA delivery applications, including high loading benefitting from positively charged ZIF-8 and large mesopores of DMONs, endosomal escape promoted by the imidazole ring of ZIF-8, and long-term glutathione depletion mediated by both zinc ions and tetrasulfide *** together, DMONs-ZIF-8 demonstrated enhanced m RNA translation and better transfection efficiency than commercial products and toxic polymer-modified DMONs in vitro and in vivo.

关键词： mesoporous organosilica nanoparticles metal-organic framework mRNA transfection cellular delivery bioregulator

Preharvest application of melatonin induces anthocyanin accumulation and related gene upregulation in red pear (Pyrus ussuriensis)

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Journal of Integrative Agriculture 2021年第8期20卷 2126-2137页

作者： SUN Hui-li wang Xin-yue SHANG ye wang Xiao-qian DU Guo-dong LÜDe-guo College of Horticulture Shenyang Agricultural UniversityShenyang 110866P.R.China Key Laboratory of Fruit Quality Development and Regulation of Liaoning Province Shenyang Agricultural UniversityShenyang 110866P.R.China

Anthocyanins are important components in the peel of red pears and contribute to the appearance of the *** application is known to affect anthocyanin biosynthesis,but the effect of preharvest melatonin application on fruit coloration remains largely *** objective of this study was to determine the effects of preharvest melatonin application on pigmentation,phenolic compounds,and the expression of related genes in Nanhong pear(Pyrus ussuriensis).The applications were performed during the pre-color-change period by spraying 50 or 200μmol L^(-1)of melatonin on *** found that treatment with melatonin had a significant effect on color *** concentrations of anthocyanins and flavonols were enhanced by melatonin treatment,whereas hydroxycinnamate and flavanol concentrations were *** real-time PCR analyses indicated that the transcription levels for most anthocyanin biosynthetic genes and anthocyanin-related transcription factors were induced by *** application also stimulated the expression of melatonin biosynthesis-related genes and consequently caused an increase in endogenous melatonin *** results provide insights into melatonin-induced fruit coloration and will facilitate the application of exogenous melatonin in agriculture.

关键词： melatonin anthocyanin pear phenolic peel pigmentation

The synergy of modulated surface polarity and oxygen vacancy for CO_(2) to methanol over Zn(δ-)-Ti(δ+)Ovacancy

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Journal of Energy Chemistry 2021年第5期30卷 449-454页

作者： Junfu Zhou Lin ye Daofeng Huang Meiyin wang Yuanhang Ren Bin yue Heyong He Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Collaborative Innovation Center of Chemistry for Energy MaterialsFudan UniversityShanghai 200438China

Bi-functional catalysts,which can be traced back to 1960s,are widely applied in energy conversion and chemical transformation[1].Generally,the enhanced performance of the bi-functional catalyst comes from the local geometry or electron density change after the second component *** changes facilitate the reaction at the structure or electron density level[2].In fact,it is a great challenge to understand and control those effects[3].

关键词： CO_(2)conversion Zn species Oxygen vacancy Synergy Formate route Synchrotron XRD

Spatio-temporal Variation of Landscape Heterogeneity under Influence of Human Activities in Xiamen City of China in Recent Decade

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Chinese Geographical Science 2013年第2期23卷 227-236页

作者： HUANG Yixiong YIN Xiuqin ye Gongfu LIN Jiemin HUANG Ru wang Na wang Liang SUN yue College of Urban and Environmental Sciences Northeast Normal University College of Geographical Sciences Fujian Normal University Fujian Academy of Forestry Sciences Quanzhou Land and Resources Bureau

Xiamen is an economically competitive and highly urbanized city along the coastal area of Fujian Province, China. The research on spatio-temporal variation of landscape heterogeneity under the influence of human activities is of great importance to the further study on the relationship of landscape pattern and ecological process. It is also crucial to the discovery of spatial variation and intensity distribution of human activities. The research analyzed the intensity of human impacts and the spatial variation features and dynamics of landscape patterns by introducing statistical theories and approaches. We analyzed spatio-temporal variation of landscape heterogeneity using the geostatistical techniques, such as semivariogram and Kriging *** show that there is a higher correlation between landscape heterogeneity indexes and human impact index. Both the indexes show a moderate spatial autocorrelation as well as an obvious characteristic of anisotropy. From 1998 to 2008, the spatial differentiation of the changes in the intensity of human activities and the changes in landscape heterogeneity shows that the landscape patterns in Xiamen are closely related with the urban land utilization methods, the condition of traffic and geographical location and the physical geographical condition such as the terrain and the ecological environment. The process of urbanization has a significant impact on the urban landscape pattern.

关键词： landscape heterogeneity human impact index human activities Xiamen City