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Release, Recycle, Rebuild： Cell-Wall Remodeling, Autodegradation, and Sugar Salvage for New Wall Biosynthesis during Plant Development

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Molecular Plant 2018年第1期11卷 31-46页

作者： William J. Barnes Charles T. Anderson Department of Biology center for Ugnocellulose structure and formation The Pennsylvania State University University Park PA 16802 USA

Plant cell walls contain elaborate polysaccharide networks and regulate plant growth, development, mechanics, cell-cell communication and adhesion, and defense. Despite conferring rigidity to support plant structures, the cell wall is a dynamic extracellular matrix that is modified, reorganized, and degraded to tightly control its properties during growth and development. Far from being a terminal carbon sink, many wall polymers can be degraded and recycled by plant cells, either via direct re-incorporation by trans- glycosylation or via internalization and metabolic salvage of wall-derived sugars to produce new precur- sors for wall synthesis. However, the physiological and metabolic contributions of wall recycling to plant growth and development are largely undefined. In this review, we discuss long-standing and recent evi- dence supporting the occurrence of cell-wall recycling in plants, make predictions regarding the develop- mental processes to which wall recycling might contribute, and identify outstanding questions and emerging experimental tools that might be used to address these questions and enhance our understanding of this poorly characterized aspect of wall dynamics and metabolism.

关键词： Plant cell walls wall degradation wall recycling wall biosynthesis

Catalytic degradation of organic pollutants for water remediation over Ag nanoparticles immobilized on amine-functionalized metalorganic frameworks

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Nano Research 2022年第9期15卷 7887-7895页

作者： Wen-Zhe Xiao Ling-Ping Xiao Yue-Qin Yang Shang-Ru Zhai Run-Cang Sun Liaoning Key Lab of lignocellulose Chemistry and BioMaterials Liaoning Collaborative Innovation Center for Lignocellulosic BiorefineryCollege of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalian 116034China

Developing efficient catalysts for organic pollutants degradation is crucial for remediating the current severe water environment,yet remains a great ***,we report silver nanoparticles immobilized on an amine-functionalized metal-organic framework(MOFs)(Ag/UiO-66-NH_(2))as a robust catalyst for the reduction of 4-nitrophenol(4-NP).The fabricated Ag/UiO-66-NH_(2)catalyst exhibits the merits of superior activities(high turnover frequency(TOF)3.2×10^(4)h^(-1)and k value 6.9×10^(-2)s^(-1)),costeffectiveness under the lowest NaBH4 concentration(n[NaBH_(4)]/n[4-NP],200),outstanding cyclability(10 recycling runs),and observable long-term durability,significantly outperforming previously reported catalytic *** excellent degradation efficiency is ascribed to the favorable microenvironment modulation of unique MOF structure,which regulates the intrinsic properties of active sites and improves the electron-transfer ***,the Ag/UiO-66-NH_(2)also promotes the catalytic degradation of several organic pollutants at room temperature and hence could find a broad application for water *** work offers a new avenue for the development of high-performance MOF-based catalysts with excellent activity and durability.

关键词： Ag/UiO-66-NH_(2) catalytic degradation organic pollutants 4-nitrophenol water remediation

Nanosilver anchored alginate/poly(acrylic acid/acrylamide) double-network hydrogel composites for efficient catalytic degradation of organic dyes

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Frontiers of Chemical Science and Engineering 2023年第7期17卷 893-905页

作者： Fan Zhang Ce Gao Shang-Ru Zhai Qing-Da An Liaoning Key Lab of lignocellulose Chemistry and BioMaterials Liaoning Collaborative Innovation Center for Lignocellulosic BiorefineryCollege of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalian 116034China

A novel alginate/poly(acrylic acid/acrylamide)double-network hydrogel composite with silver nanoparticles was successfully fabricated using the sol–gel *** presence of carboxyl and amide groups in the network structure provided abundant active sites for complexing silver ions,facilitating the in situ reduction and confinement of silver *** batch experiments,the optimal silver loading was 20%,and 5 mmol·L^(–1) of p-nitrophenol was completely degraded in 113 s with a rate constant value of 4.057×10^(−2) s^(–1).In the tap water system and simulated seawater system,the degradation time of p-nitrophenol at the same concentration was 261 and 276 s,respectively,with a conversion rate above 99%.In the fixed-bed experiment,the conversion rate remained above 74%after 3 h at a flowing rate of 7 mL·min^(–1).After 8 cycling tests,the conversion rate remained at 98.7%.Moreover,the catalyst exhibited outstanding performance in the degradation experiment of four typical organic dyes.

关键词： double-network hydrogel dye degradation silver nanoparticles alginate

Near-infrared and Multicolor Electrochromic Device Based on Polyaniline Derivative

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Chinese Journal of Polymer Science 2014年第8期32卷 1040-1051页

作者： Zhong-qiu Tong Hai-ming Lv Jiu-peng Zhao 李垚 center for Composite Materials and structure Harbin Institute of Technology School of Chemical Engineering and Technology Harbin Institute of Technology

Electroactive conducting copolymers of aniline （ANI） and diphenylamine （DPA） are prepared on indium tin oxide （ITO） surface from 1 mol/L H2SO4 aqueous solution with different feed ratios of ANI to DPA by using a potentiostatic method. FTIR spectra and SEM measurements are used to confirm the formation of copolymers. Due to the combination of the N,N＇-diphenyl benzidine and aniline units in the molecular chain, the copolymer films exhibit improved electrochemical and electrochromic properties, compared to PANI and PDPA. The copolymer [marked as P（ANI9-co-DPA1）] film prepared at a ratio of 9：1 （ANI/DPA） exhibits novel transmittance modulation both in visible and near-infrared （NIR） region between -0.8 V and 0.8 V （52% and 67% respectively） and fast response time （3.6 s for coloration and 2.3 s for bleaching at 600 nm）. An electrochromic device （ECD） based on P（ANI9-co-DPA1） and PEDOT：PSS is also fabricated and shows a multicolor electrochromic performance, with a good optical contrast （29% in visible region and 40% in NIR region）, acceptable response time （8.3 s for coloration and 7.5 s for bleaching at 600 nm） and long-term stability. Clear color changes from transparent （-0.8 V）, bright green （0 V）, seagreen （0.4 V） to dark slate gray （0.8 V） are demonstrated.

关键词： Conjugated polymer Spectroelectrochemistry Electrochromic device Polyaniline.

structure and flaws of CuCr alloys by explosive compaction

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Journal of Harbin Institute of Technology(New Series) 2005年第2期12卷 134-138页

作者：李金平孟松鹤韩杰才 center for Composite Materials and structure Harbin Institute of Technology Harbin 150001 China

CuCr alloys are prepared by mechanical alloying and explosive compaction. After we have studied their structure and flaws, the results show that the CuCr alloys have definite strength and toughness, while their fractured surface displays ductile characteristics. In the metallurgical structure, CuCr alloys are composed of two phases of uniform distribution; the SEM morphology is like thin strips with an end arrangement that is bonded to each other and the two-phase distribution of CuCr alloys is more homogenous. It is in only in a very small zone that formation of Cu-rich and Cr-rich phases take place. The flaws of the compaction samples are mainly central-holes and cracks.

关键词： CuCr alloys explosive compaction morphology flaws

Customization of FeNi alloy nanosheet arrays inserted with biomass-derived carbon templates for boosted electromagnetic wave absorption

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 812-824页

作者： Xuanqi Yang Honghan Wang Jing Chen Qingda An Zuoyi Xiao Jingai Hao Shangru Zhai Junye Sheng Liaoning Key Lab of lignocellulose Chemistry and BioMaterials Liaoning Collaborative Innovation Center for Lignocellulosic BiorefineryCollege of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalian 116034China Qingdao Medical College Qingdao UniversityQingdao 266071China

Electromagnetic wave(EMW)-absorbing materials have considerable capacity in the military field and the prevention of EMW radiation from harming human ***,obtaining lightweight,high-performance,and broadband EMW-absorbing material remains an overwhelming *** dielectric/magnetic composites with customized structures is a strategy with great promise for the development of high-performance EMW-absorbing *** layered double hydroxides as the precursors of bimetallic alloys and combining them with porous biomass-derived carbon materials is a potential way for constructing multi-interface heterostructures as efficient EMW-absorbing materials because they have synergistic losses,low costs,abundant resources,and light ***,FeNi alloy nanosheet array/Lycopodium spore-derived carbon(FeNi/LSC)was prepared through a simple hydrothermal and carbonization ***/LSC presents ideal EMW-absorbing performance by benefiting from the FeNi alloy nanosheet array,sponge-like structure,capability for impedance matching,and improved dielectric/magnetic *** expected,FeNi/LSC exhibited the minimum reflection loss of-58.3 dB at 1.5 mm with 20wt%filler content and a widely effective absorption bandwidth of 4.92 ***/LSC composites with effective EMW-absorbing performance provide new insights into the customization of biomass-derived composites as high-performance and lightweight broadband EMW-absorbing materials.

关键词： spore-derived carbon FeNi alloy nanosheet array multi-interface heterostructures synergistic effect efficient electromagnet-ic wave absorption

Study on Nucleophilic Additions to endo-tricyclo[5.2.1.0^(2,6)]deca-2(6),8-dien-3-one and an Unusual Payne Rearrangement of α,β-Epoxy Tricyclodecenone

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Chinese Chemical Letters 2001年第7期12卷 585-588页

作者： Xue Shi MAO A.A.VOLKERS A.J.H.KLUNDER Binne ZWANENBURG Department of Organic Chemistry NSR Center for Molecular StructureDesign and SynthesisUniversity of NijmegenToernooiveld 16525 ED NijmegenThe Netherlands

Synthesis of highly strained tetracyclic ketones was achieved by cyclopropanation or epoxidation of tricyclodecenone 1. An unusual formation of α-methoxy β-hydroxy ketone from an α,β-unsaturated enone system via ... 详细信息

关键词： Nucleophilic addition Payne rearrangement α β-epoxycyclopentanone

formation of M_(n+1)AX_n phases in Ti–Cr–Al–C systems by self-propagating high-temperature synthesis

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Rare Metals 2014年第4期33卷 419-426页

作者： Guo-Bing Ying Xiao-Dong He Shan-Yi Du Chun-Cheng Zhu Yong-Ting Zheng Yu-Ping Wu Cheng Wang Institute of Metals and Protection College of Mechanics and MaterialsHohai University center for Composite Materials and structure Harbin Institute of Technology College of Chemistry and Chemical Engineering Harbin Normal University

In this paper, phase composition of the Mn＋l- AXn phases by self-propagating high-temperature synthesis （SHS） was determined using Ti, Cr, A1, and carbon black as raw materials. And, phase composition and micro- structures of the Mn＋1AXn phases-contained bulk by SHS with the pseudo-hot isostatic pressing （SHS/PHIP） were investigated in Ti-Cr-AI-C systems raw materials. Riet- veld XRD refinement was introduced to study the lattice parameters and phase composition of the resultant phases from the SHSed and SHS/PHIPed samples. Ti2A1Cx, Ti3A1C2, and Cr2A1Cx by SHS were detected in the Ti-Cr- A1-C systems, as well as the binary carbide of TiC and intermetallics. The mechanical properties of the synthe- sized bulk samples were determined, exhibiting a high strength and toughness compared with the typical mono- lithic Mn＋1AXn phase ceramics. It is indicated that the samples prepared by SHS/PHIP are identified to be a strategy for improving the mechanical properties of monolithic Mn＋1AXn phase.

关键词： SHS/PHIP Mn+lAXn phases Phasecomposition Microstructure Mechanical properties

Hot Tensile Behaviors and Microstructure Evolution of Ti-6Al-4V Titanium Alloy Under Electropulsing

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Acta Metallurgica Sinica(English Letters) 2018年第12期31卷 1287-1296页

作者： Dong-Wei Ao Xing-Rong Chu Shu-Xia Lin Yang Yang Jun Gao Associated Engineering Research center of Mechanics and Mechatronic Equipment Shandong University A Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of Matter Chinese Academy of Science

The effect of electropulsing on the mechanical behaviors and microstructures of Ti-6Al-4V titanium alloy was investigated by an uniaxial tensile test. Compared to the value measured in cold tensile test, the alloy exhibits lower ultimate tensile strength when the tensile deformation is assisted by electropulsing. The tensile elongation is found to vary non-monotonically with increasing root mean square(RMS) current density. Though decreasing at first, the tensile elongation increases with current density once the value exceeds 8.1 A/mm^2. Through applying current with RMS current density of 12.7 A/mm^2, the tensile elongation at strain rate 0.001 s^(-1) can be improved by 94.1%. In addition, it is observed that more remarkable electroplastic effect is induced by the higher peak current density under similar thermal effect. Microstructure analysis reveals that the low plasticity at 8.1 A/mm^2 is attributed to the micro-void easily formation near the tips of acicular β phases. The enhanced ductility at higher current densities, on the other hand, is attributed to the dynamic recrystallization.

关键词： Ti-6Al-4V alloy Electropulsing Mechanical properties Microstructure Fracture morphology