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Journal of Renewable Materials 2021年第12期9卷 2291-2301页

作者： Wenting Ren fei guo Minghui Liu Haocheng Xu Hankun Wang Yan Yu Institute of New Bamboo and Rattan Based Biomaterials International Center for Bamboo and RattanBeijing100102China College of Material Engineering Fujian Agriculture and Forestry UniversityFuzhou350108China NFGA and Beijing Co-Built Key Laboratory of Bamboo and Rattan Science&Technology National Forestry and Grassland AdministrationBeijing100102China

Understanding the assembly and spatial arrangement of bamboo cell wall components is crucial for its optimal *** cell walls consist of aggregates of cellulose microfibrils and *** the present study,the size and arrangement of cellulose microfibril aggregates in the cell walls of sclerenchyma fibers and parenchyma cells in moso bamboo were investigated with NMR and *** NMR measurement showed that the characteristic sizes of the microfibril aggregates of fibers and parenchyma cells were approximately 25.8 nm and 18.8 nm,***,high-resolution SEM showed the size of microfibril aggregates varied little across the cell wall of sclerenchyma ***,there were significant size differences between the broad and narrow lamellae both in fiber and parenchyma cells,which is thought to be closely related to the orientation of microfibrils in these *** microfibril aggregates in the fibers mainly appear in a random arrangement,although occasionally in a radial or tangential arrangement in individual *** cells have a relatively thinner cell wall layers,in which microfibril aggregates appear in a concentric lamellar arrangement.

关键词： Bamboo fiber parenchyma cell microfibril aggregate size arrangement

Cu(In,Ga)Se2 absorbers prepared by electrodeposition for low-cost thin-film solar cells

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Rare Metals 2017年第9期36卷 729-736页

作者： Jing-Yu Qu Zheng-fei guo Kun Pan Wei-Wei Zhang Xue-Jin Wang College of Science China Agricultural UniversityBeijing 100083China

Reducing the manufacturing cost of solar cells is necessary to their industrial production. Electrodepositing is an effective, non-vacuum method which is very suitable for cutting the manufacturing cost of thin films as well as developing its large-scale industrial production. In this study, about 1-μm-thick Cu（In,Ga）Se2（CIGS） precursors were electrodeposited on Mo/glass substrates in aqueous solution utilizing a three-electrode potentiostatic *** was used as complexing agent, and all parameters of electrodeposition were precisely *** that, the electrodeposited precursors were selenized in a Se atmosphere with different heating ramp rates（60 and 600℃·min^（-1））. High-quality CIGS films were obtained, and their characteristics were investigated by X-ray fluorescence, scanning electron microscopy, energydispersive spectroscopy, X-ray diffraction, Raman spectra and near-infrared-visible（NIR-Vis） spectra. The results reveal that there are many differences between the properties of the films under different heating rates. Finally,CIGS solar cells were fabricated using a fast and a slow heating rate. The maximum efficiencies achieved for the films selenized at 60 and 600℃-min^（-1） are 3.15% and 0.71%, respectively.

关键词： Cu(In,Ga)Se2 Thin films Electrodeposition Selenization Heating rates

A global invasion by the thrip,Frankliniella occidentalis:Current virus vector status and its management

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Insect Science 2020年第4期27卷 626-645页

作者： Zhen He Jing-fei guo Stuart RReitz Zhong-Ren Lei Sheng-Yong Wu State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina School of Horticulture and Plant Protection Yangzhou UniversityYangzhouJiangsu ProvinceChina Malheur Experiment Station Oregon State UniversityOntarioORUSA

Western flower thrip,Frankliniella occidentalis(Pergande),is among the most economically important agricultural pests globally,attacking a wide range of vegetable and horticultural *** addition to causing extensive crop damage,the species is notorious for vectoring destructive plant viruses,mainly belonging to the genera Orthotospovirus,*** and *** infected by orthotospoviruses,thrips can remain virulent throughout their lifespan and continue transmitting viruses to host plants when and wherever they *** irruptive viral outbreaks in crops will permanently disrupt functional integrated pest management systems,and typically require a remedial treatment involving insecticides,contributing to further development of insecticide *** mitigate against this continuing cycle,the most effective management is early and comprehensive surveillance of the pest species and recognition of plant viruses in the *** review provides information on the pest status of ***,discusses the current global status of the viruses vectored by this thrip species,examines the mechanisms involved in transmitting virus-induced diseases by thrips,and reviews different management strategies,highlighting the potential management tactics developed for various cropping *** early surveillance and the utilization of potential methods for control of both F occidentalis and viruses are proposed.

关键词： global distribution integrated pest management invasion thrips viruses transmission

Magnetic separation of pentlandite from serpentine by selective magnetic coating

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International Journal of Minerals,Metallurgy and Materials 2019年第1期26卷 1-10页

作者： Ji-wei Lu Zhi-tao Yuan Xiao-fei guo Zhong-yun Tong Li-xia Li School of Resources and Civil Engineering Northeastern University Shaanxi Key Laboratory for the Comprehensive Utilization of Tailings Resources Shangluo University School of Mining Engineering University of Science and Technology Liaoning

In this study, pentlandite was selectively separated from serpentine using magnetic coating technology by adjusting and optimizing pH, stirring speeds, magnetic field intensities, and dosages of sodium hexametaphosphate(SHMP) and sodium oleate(SO). A magnetic concentrate with Ni grade of 20.8% and Ni recovery of 80.5% was attained under the optimized operating conditions. Considering the above, the adsorption behaviors of SHMP and SO and the surface properties of minerals after the magnetic coating were studied by Fourier transform infrared(FTIR) spectroscopy, X-ray diffraction(XRD), and scanning electron microscopy(SEM). The results show that magnetite was preferentially coated on the pentlandite surfaces and sparingly coated on the serpentine surfaces in the presence of SHMP and SO. Furthermore, calculations by Derjaguin-Landau-Verwey-Overbeek(DLVO) theory indicate that the preferential adsorption of magnetite on the pentlandite surfaces is due to the presence of a hydrophobic interaction between the magnetite and pentlandite, which is much stronger than the interaction between magnetite and serpentine.

关键词： dispersant coagulant magnetic coating magnetic separation hydrophobic interaction

Influence of pre-stretching on the tensile strength,fatigue properties and the in-plane anisotropy in Al-Cu-Li alloy AA2099

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Journal of Materials Science & Technology 2023年第14期145卷 249-259页

作者： Xianghui Zhu Xusheng Yang Weijiu Huang Weiyi Qiu Xin Wang fei guo Li Hu Miao Gong College of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China College of Materials Science and Engineering Chongqing University of Arts and SciencesChongqing 402160China College of Materials Science and Engineering Chongqing University of TechnologyChongqing 400044China

The influence of pre-stretching prior to artificial aging on microstructure,tensile properties,and fatigue behavior of AA2099-T8 sheets was *** results showed that increased pre-strain level from 1%to 6%resulted in a more uniform distribution and increasing density of the T_(1)*** localized plastic deformation during pre-stretching led to the formation of dense precipitation bands(DPBs)and precipitation free bands(T_(1)-PFBs)in the sheets with the 1%*** non-uniform distribution of the T_(1)phase with T_(1)-PFBs and DPBs resulted in a decrement in elongation and a strong in-plane anisotropy of tensile *** appropriate level of pre-strain should be executed aiming to improve elongation and reduce the tensile anisotropy by promoting a uniform distribution of the T_(1)***-plane anisotropy of yield strength due to the presence of DPBs and T_(1)-PFBs was quantitatively analyzed by the modified Hall-Petch *** results of the calculation for the modified model showed good agreement with the *** addition,resistances of fatigue crack propagation(FCP)in the same orientation were gradually decreased with the increment of pre-strain due to the increment in yield strength and more uniform distribution of the T_(1)*** the in-plane anisotropy of FCP resistance,the main reasons were the development of rough fracture surfaces and the transgranular fracture modes in L-T orientation.

关键词： Aluminum-lithium alloys Precipitation Mechanical properties Fatigue crack propagation

Variation of mechanical properties and microstructure of hot-rolled AA2099 Al-Li alloy induced by the precipitation during preheating process

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Journal of Materials Science & Technology 2022年第15期110卷 198-209页

作者： fei guo Weijiu Huang Xusheng Yang Haipeng Dong Hang Yu Qiuyu Chen Li Hu Luyao Jiang College of Materials Science and Engineering Chongqing University of TechnologyChongqing 400054China College of Materials Science and Engineering Chongqing University of Arts and ScienceChongqing 402160China Chongqing Materials Research Institute Co. LtdChongqing 400707China

Preheating is the first step for thermal-mechanical processing of the materials. Several preheating schedules were designed based on industrial manufacturing to explore their effect on the microstructure and mechanical properties of AA2099 Al-Li alloy during the following hot rolling. The results show that the mechanical properties of as-rolled sheets are quite sensitive to preheating. Various types of secondary phases, including δ', T1 and T2 phases, were precipitated during the heating process. The difference among precipitates is the main reason to induce the variation of mechanical properties for as-rolled sheets. A rapid heating rate gave rise to the precipitation of δ' phase, which largely promoted yield stress and ultimate tensile strength in as-rolled sheets. T1 phase was more favorable in the preheating with a holding period at 150–250 °C, which caused a moderated strain hardening behavior. Precipitates formed during preheating induced different slip behaviors in the following deformation. The coexistence of T1 and δ' phase could restrict planar slip, which inhibited the formation of the shear band. The difference in the activity of non-octahedral slips and planar slips determined the strain hardening effect, which should be the reason for the variation of mechanical properties of as-rolled sheets.

关键词： Aluminum-lithium alloys Preheating Precipitation Mechanical properties Shear band

Mixed 2D-Dion–Jacobson/3D Sn-Pb alloyed perovskites for efficient photovoltaic solar devices

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Nano Research 2023年第2期16卷 3142-3148页

作者： Zhili Lu Chaohui Li Hongwei Lai Xinming Zhou Chunfeng Wang Xianhu Liu fei guo Caofeng Pan National Engineering Research Center for Advanced Polymer Processing Technology Key Laboratory of Advanced Material Processing&Mold(Ministry of Education)Zhengzhou UniversityZhengzhou 450002China Institute of New Energy Technology College of Information Science and TechnologyJinan UniversityGuangzhou 510632China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesNational Center for Nanoscience and Technology(NCNST)Beijing 100083China Institute of Materials for Electronics and Energy Technology(i-MEET) Friedrich-Alexander University Erlangen-NürnbergMartensstrasse 7Erlangen 91058Germany

Tin-lead(Sn-Pb)alloyed perovskites with tunable bandgaps hold great potential for constructing highly efficient single-junction and tandem photovoltaic ***,the efficiency and stability of Sn-Pb perovskite solar cells(PSCs)are greatly hampered by severe nonradiative recombination due to the easy oxidation of Sn(II).In this work,we report the construction of mixed dimensional two-dimensional(2D)Dion–Jacobson(DJ)and three-dimensional(3D)perovskites to improve the efficiency and stability of Sn-Pb alloyed *** a small amount of 1,4-butanediammonium diiodide as spacer cations of DJ perovskites into precursor,the prepared mixed dimensional Sn-Pb alloyed perovskites exhibit reduced trap-state density due to the passivation of 2D DJ *** a result,nonradiative charge recombination is greatly *** prepared Sn-Pb alloyed PSCs based on 2D-DJ/3D heterojunction deliver a power conversion efficiency of 19.02%with an impressive fill factor of 80%.As well,improved device stability is realized due to the presence of DJ perovskites which serves as a protection barrier against oxidation and water invasion.

关键词： Sn-Pb perovskite narrow bandgap Dion–Jacobson perovskite solar cells two-dimensional(2D)/three-dimensional(3D)

Rolling texture development in a dual-phase Mg-Li alloy:The role of temperature

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Journal of Magnesium and Alloys 2023年第8期11卷 2980-2990页

作者： Xiaoyan Li fei guo Yanlong Ma Luyao Jiang Hongliang Lai Haiding Liu Dingfei Zhang Risheng Pei College of Materials Science and Engineering Chongqing University of TechnologyChongqing 400054China Chongqing Materials Research Institute Co. LtdChongqing 400707China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Institut für Metallkunde und Metallphysik RWTH Aachen UniversityAachen 52056Germany

Dual-phase Mg-Li alloys sheets were rolled at four different temperatures ranging from liquid nitrogen to 300℃to explore effect of rolling temperature on texture and mechanical properties of the *** plasticity simulation was utilized to illustrate the influence of slip activity on rolling texture *** results show that the rolling texture is largely depended on deformation *** commercial Mg alloys,the critical resolved shear stress of basal slip inα-Mg phase of Mg-Li alloy decreased more significantly by increasing temperature compared to that of pyramidal*** of basal slip by increasing temperature triggered a decrease of split angle of basal poles for the double-peak ***slip largely enhanced by increasing temperature upon 200℃,which induced a wider orientation spread along the transverse *** theβ-Li phase,the promotion of{110}slip system at elevated temperature triggered the enhancement of{211}and{111}texture *** cryo-rolled sample exhibited the highest strength compared to the others due to a strong hardening behavior at this temperature.A two-stage hardening behavior was observed in these as-rolled dual-phase *** transition at phase boundaries could be the reason for appearance of this two-stage hardening.

关键词： Magnesium-Lithium alloys Dual-phase Texture Slip behavior Mechanical properties

Modified onlay island flap versus tubularized incised plate urethroplasty for hypospadias reoperation

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Asian Journal of Andrology 2023年第5期25卷 583-586页

作者： Xiao-Jiang Zhu Yong-Ji Deng Jun Wang Yun-fei guo Zheng Ge Department of Urology Children's Hospital of Nanjing Medical UniversityNanjing 210008China

This study aimed to assess the outcomes of modified onlay island flap(MOIF)urethroplasty for hypospadias reoperation.A retrospective analysis was conducted using clinical data on children reoperated with MOIF or tubularized incised plate(TIP)urethroplasty for hypospadias in the Children's Hospital of Nanjing Medical University(Nanjing,China)from December 2016 to September 2020.A total of 90 children with hypospadias who failed primary repair and were reoperated on with MOIF(MOIF group,n=46)or TIP urethroplasty(TIP group,n=44)were *** children were postoperatively followed up for at least 6 *** patients with postoperative urinary fistula,2 patients with glans dehiscence,and 1 patient with urethral diverticulum were reported in the MOIF group,while 7 patients with postoperative urinary fistula,2 patients with urethral stricture,and 1 patient with glans dehiscence were reported in the TIP *** infection,flap necrosis and other complications were not recorded.A total of 37(80.4%)patients in the MOIF group and 34(77.3%)patients in the TIP group were successfully *** the success rates of MOIF and TIP urethroplasty are comparable,pediatricians should master different types of repair techniques for individualized hypospadias *** urethroplasty can be recommended after failure of the primary repair.

关键词： children hypospadias reoperation urethroplasty

The role of recrystallization and grain growth in optimizing the sheet texture of magnesium alloys with calcium addition during annealing

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Journal of Magnesium and Alloys 2020年第1期8卷 252-268页

作者： fei guo Risheng Pei Luyao Jiang Dingfei Zhang Sandra Korte-Kerzel Talal Al-Samman College of Materials Science and Engineering Chongqing University of Technology400054 ChongqingChina Chongqing Key Laboratory of Mold Technology Chongqing University of Technology400054 ChongqingChina Institut für Metallkunde und Metallphysik RWTH Aachen University52056 AachenGermany College of Materials Science and Engineering Chongqing University400044 ChongqingChina

The contribution of recrystallization and grain growth to the texture evolution in AZ31 alloy and a modified version AZ31+0.5 wt.%Ca was investigated utilizing a multi-step annealing *** results showed that the addition of Ca triggered a considerable texture modification by increasing the texture spread and decreasing the overall texture *** effect was found to be temperature *** the annealing temperature remained lower than 450℃,a weak double peak texture with large basal pole tilt towards the RD was *** is correlated to microstructure observations of a large number of Ca-containing nano-sized particles that seemed to suppress grain growth below 450℃,which stabilized the weak recrystallization *** favorable texture was lost upon annealing at higher *** AZ31,recrystallization nuclei were found to preserve the orientation of their deformed parents,which offered limited potential to optimize the texture via annealing *** growth of recrystallized grains resulted in a distinct sheet texture transition from a double-peak to a single-peak basal *** of grain boundary energy and grain topology are discussed to explain the growth advantage of the sharp basal component over other orientations.

关键词： Magnesium alloys Microstructure Texture Recrystallization Grain growth