Abnormal IR Spectra of CO Adsorbed on the Surface of Glass Carbon Electrode Modified with Polypyrrole Film with Platinum Microparticles

Abnormal IR spectra of CO adsorbed at the surface of glass carbon electrode modified with polypyrrole film with Pt microparticles are reported.

Study of the Diffusion Behavior of Seawater Absorption in Multi-Walled Carbon Nanotubes/Halloysite Nanotubes Hybrid Nanofillers Modified Epoxy-Based Glass/Carbon Fiber Composites

In the maritime industry, cost-effective and lightweight Fiber Reinforced Polymer (FRP) composites offer excellent mechanical properties, design flexibility, and corrosion resistance. However, their reliability in harsh seawater conditions is a concern. Researchers address this by exploring three approaches: coating fiber surfaces, hybridizing fibers and matrices with or without nanofillers, and interply rearrangement. This study focuses on evaluating the synergistic effects of interply rearrangement of glass/carbon fibers and hybrid nanofillers, specifically Multi-walled carbon nanotubes (MWCNT) and Halloysite nanotubes (HNT). The aim is to enhance impact properties by minimizing moisture absorption. Hybrid nanocomposites with equal-weight proportions of two nanofillers: 0 wt.%, 1 wt.%, and 2 wt.% were exposed to seawater for 90 days. Experimental data was subjected to modelling through the application of Predictive Fick’s Law. The study found that the hybrid composite containing 2 wt.% hybrid nanofillers exhibited a 22.10% increase in impact performance compared to non-modified counterparts. After 90 days of seawater aging, the material exhibited enhanced resistance to moisture absorption (15.74%) and minimal reduction in impact strength (8.52%) compared to its dry strength, with lower diffusion coefficients.

Electrochemical Study and Application on Shikonin at Poly（diallyldimethylammonium chloride） Functionalized Graphene Sheets Modified Glass Carbon Electrode

The electrochemical behaviors of shikonin at a poly（diallyldimethylammonium chloride） functionalized graphene sheets modified glass carbon electrode（PDDA-GS/GCE） have been investigated. Shikonin could exhibit a pair of well-defined redox peaks at the PDDA-GS/GCE located at 0.681 V（Epa） and 0.662 V（Epc）[vs. saturated calo- mel electrode（SCE）] in 0.1 mol/L phosphate buffer solution（pH=2.0） with a peak-to-peak separation of about 20 mV, revealing a fast electron-transfer process. Moreover, the current response was remarkably increased at PDDA- GS/GCE compared with that at the bare GCE. The electrochemical behaviors of shikonin at the modified electrode were investigated. And the results indicate that the reaction involves the transfer of two electrons, accompanied by two protons and the electrochemical process is a diffusional-controlled electrode process. The electrochemical para- meters of shikonin at the modified electrode, the electron-transfer coefficient（a）, the electron-transfer number（n） and the electrode reaction rate constant（ks） were calculated to be as 0.53, 2.18 and 3.6 s^-1, respectively. Under the optimal conditions, the peak current of differential pulse voltammetry（DPV） increased linearly with the shikonin concentra- tion in a range from 9A72×10^-8 mol/L to 3,789×10^-6 mol/L with a detection limit of 3,157× 10^-8 mol/L. The linear regression equation was Ip=O.7366c＋0.7855（R=0.9978; lp： 10-7 A, c： 10-8 mol/L）. In addition, the modified glass carbon electrode also exhibited good stability, selectivity and acceptable reproducibility that could be used for the sensitive, simple and rapid determination of shikonin in real samples. Therefore, the present work offers a new way to broaden the analytical application of graphene in pharmaceutical analysis.

Kinetics of Glass Transition and Crystallization in Carbon Nanotube Reinforced Mg-Cu-Gd Bulk Metallic Glass

Mg65Cu25Gd10 bulk metallic glass and its carbon nanotube reinforced composite were prepared. Differential scanning calorimeter （DSC） was used to investigate the kinetics of glass transition and crystallization processes. The influence of CNTs addition to the glass matrix on the glass transition and crystallization kinetics was studied. It is shown that the kinetic effect on glass transition and crystallization are preserved for both the monothetic glass and its glass composite. Adding CNTs in to the glass matrix reduces the influence of the heating rate on the crystallization process. In addition, the CNTs increase the energetic barrier for the glass transition. This results in the decrease of GFA. The mechanism of the GFA decrease was also discussed.

Effect of Ultrasonication on the Properties of Multi-walled Carbon Nanotubes/Hollow Glass Microspheres/Epoxy Syntactic Foam

Multi-walled carbon nanotubes（MWCNTs） reinforced hollow glass microspheres（HGMs）/epoxy syntactic foam was fabricated. The effects of ultrasonication on the density, compression strength, and water absorption properties were studied. Better dispersed MWCNTs can be obtained after ultrasonication treatment, but an increasing viscosity will lead to a larger amount of voids during syntactic foam preparation especially when the content of HGMs is more than 70 vol%. The existing voids will decrease the density of epoxy syntactic foam. However, the ultrasonication does not change the compression strength much. Ultrasonication treatment will decrease the water absorption content due to the better dispersion and hydrophobic properties of MWCNTs. But a significant increase of water absorption content occurs when HGMs is more than 70 vol%, which is attributed to the higher viscosity and larger amount of voids.

High-cycle Fatigue Life Extension of Glass Fiber/Polymer Composites with Carbon Nanotubes

The present work shows that the addition of small volume fractions of multi-walled carbon nanotubes （CNTs） to the matrix results in a significant increase in the high-cycle fatigue life. It is proposed that carbon nanotubes tend to inhibit the formation of large cracks by nucleating nano-scale damage zones. In addition, the contribution to energy absorption from the fracture of nanotubes bridging across nano-scale cracks and from nanotube pull-out from the matrix are mechanisms that can improve the fatigue life. An energy-based model was proposed to estimate the additional strain energy absorbed in fatigue. The distributed nanotubes in the matrix appear to both distribute damage as well as inhibit damage propagation resulting in an overall improvement in the fatigue strength of glass fiber composites.

MECHANICAL PROPERTIES OF CARBON/GLASS FIBER REINFORCED POLY(METHYL METHACRYLATE)COMPOSITES

Artificial bone, carbon/glass fiber reinforced PM-MA composites have been prepared by hot press moulding of pre-preg -which monofilments of CF and GF impregnated by MMA prepolymer. When the PMMA volume fraction in com-posites is 50% > theoretical and experimental results show that strength and modules of these hybrid composites are in accord with 'rule of mixture'. The tensile and flexure strength are the lowest when the raletive volume fraction of carbon fiber in rein-forcements is 50%,SEM examinations further explained re-sults.

Influence of Angle Ply Orientation on Tensile Properties of Carbon/Glass Hybrid Composite

Hybrid composites are considered materials of great potential for engineering applications. One advantage of hybrid composite materials for the designer is that the properties of a composite can be controlled to a considerable extent by the choice of fibers and matrix and by adjusting the orientation of the fiber. The scope for this tailoring of the properties of the material is much greater, however, when different kinds of fiber orientations are incorporated in the same resin matrix. For the study of potential of these materials, in this work specimens were prepared with different angle ply ori entation of carbon/glass hybrid with epoxy resin as an adhesive. Three orientations viz 0°/90°, 45°/45° and 30°/60° were considered for studies. Mechanical properties such as tensile strength, tensile modulus, & peak load of the hybrid com posites were determined as per ASTM standards. Vacuum bagging technique was adopted for the fabrication of hybrid specimens. It was observed that angle ply orientation at 0°/90° showed significant increase in tensile properties as compared to other orientation. Scanning electron micrographs of fractured surfaces were used for a qualitative evaluation of interfacial properties of woven carbon-glass hybrid composites. These results indicated that carbon-glass hybrid composites offered the merits of synthetic fibers.

Influence of Glass Dust on Properties of Alumina-carbon Refractories

In order to improve the properties of alumina-carbon refractories,specimens were prepared using white fused corundum,zirconia-mullite and flake graphite as the raw materials,phenolic resin as the binder,adding different mass fractions(1.5%,2.0%,and 2.5%,respectively)of glass dust,cold isostatic pressing by 120 MPa,drying and firing at 900℃for 3 h.Effects of the glass dust addition on the apparent porosity,bulk density,cold modulus of rupture,hot modulus of rupture and thermal shock resistance were studied.The results show that the cold modulus of rupture of the specimens is improved significantly as the results of glass dust accelerating sintering.However,the hot modulus of rupture decreases.As the glass phase buffers the strain produced by thermal shock,the thermal shock resistance of alumina-carbon specimens is improved,especially for low carbon alumina-carbon materials.

Adsorption of Cu and Ni Ions from Aqueous Solutions by Commercial Activated Carbon and the Reutilization in Glass Coloration

Toxic Cu(Ⅱ) and Ni(Ⅱ) ions in aqueous solutions were adsorbed by microporous activated carbon(AC). The adsorption isotherm and kinetics correlation coefficients indicate that the adsorption of Cu(Ⅱ) and Ni(Ⅱ) ions on the AC fits the pseudo second-order rate model and Langmuir adsorption model. The used AC adsorbents containing the adsorbed Cu and Ni ions were used as colorant in glass preparation. The coloration effect of Cu ions was influenced by the carbon absorbent included in the glass batch due to the reduction phenomenon, while the coloration of Ni ions was not affected.

Thermo-Stamping Process of Glass and Carbon-Fibre Reinforced Polymer Composites

In this work, manufacturing tools for thermoplastic (TP) composites have been developed. The chosen process involves the stacking alternately of oriented dry fabrics and TP films and does not use semi-products in order to reduce material costs. This study was specifically directed towards optimizing the impregnation of continuous glass and carbon fibres reinforcing two TP amorphous matrices, the polyphenylsulfone (PPSU) and polyetherimide (PEI), to obtain semi-finished products employed for aeronautical structures. The impregnation quality of inter and intra-yarns is analyzed and validated by optical and scanning micrographic observations conducted with an optical and a Scanning Electron Microscopies (SEM), respectively. The study showed that besides the process parameters and porosity distribution in the core of warp yarns, the impregnation quality depends on the surface properties of constituents. Desizing treatment has been carried out to improve the wettability of fibres by the TP matrices.

湿热环境下玻/碳纤维混杂复合材料梁阻尼特性的细观力学分析

基于复合材料细观力学,利用能量耗散原理及宏观应变能法建立了湿热环境下玻/碳纤维混杂复合材料层合梁的阻尼预测模型。利用MATLAB软件编写了湿热环境下玻/碳纤维混杂复合材料损耗因子的计算程序,研究了纤维铺设角度、体积分数、铺层顺序以及湿热效应对玻/碳纤维混杂复合材料层合梁阻尼性能的影响规律。结果表明:湿热环境导致材料产生湿热应变是影响阻尼特性的主要机理;玻/碳纤维混杂复合材料层合梁的损耗因子均随温度及吸水浓度的增大而增大,且温度的影响远大于吸水浓度的影响;纤维体积分数越高,受湿热影响程度越大;铺层角度对损耗因子影响远高于湿热、混杂方式、纤维体积分数的影响。

玻璃与碳纤维混杂增强复合材料3D打印与实验

本研究基于热塑性材料熔融沉积成型工艺,研制了双喷头连续玻璃纤维与碳纤维混杂增强热塑性复合材料结构增材制造平台,制备了不同混杂比的纤维增强热塑性复合材料结构试件,分析了不同结构试件的弯曲力学性能与失效模式,探索了嵌入碳纤维智能层的混杂纤维增强热塑性复合材料的力阻行为。结果表明:比较纯热塑性材料结构件,玻璃纤维增强复合材料结构件弯曲强度提高了115.99%,碳纤维增强复合材料结构件弯曲强度提高了198.76%;玻璃纤维与碳纤维混杂增强复合材料结构件具有负弯曲强度混杂效应和正弯曲模量混杂效应。可根据碳纤维电阻相对变化率对混杂增强复合材料结构的应变与断裂破坏状态进行实时自感知。研究结果为连续玻璃纤维与碳纤维混杂增强热塑性复合材料结构件的高质高效制造与智能化提供了新工艺与新思路。

吸波/防弹复合材料的研发

采用玻璃纤维布/改性环氧树脂、碳纤维布/环氧树脂以湿法手糊成型工艺制备透波层和反射层,并与吸波浆料浸渍后的芳纶蜂窝芯复合制成电磁屏蔽材料。将电磁屏蔽材料与芳纶防弹板复合制成吸波/防弹一体化材料,该材料可满足GA 141—2010防弹标准要求,在频率2~18 GHz范围的最大反射率可达-25 dB,具有较好的吸波性能。

我国建筑玻璃工业碳排放量预测

建筑玻璃工业属于能源和碳排放密集型产业,行业本身减排难度大同时肩负建筑领域碳中和重任,建筑玻璃需求仍将持续增长,进一步加大减排难度。通过分析2010—2022年建筑面积和建筑玻璃产量数据,对建筑玻璃面积-建筑面积进行线性拟合,结合对未来建筑面积的情景分析,预测2023—2040年建筑玻璃需求量和碳排放量,并量化分析减薄等主要达峰路径。预测结果分析可得:加速减薄玻璃厚度,在保障建筑对玻璃面积规模需求的同时,可实现建筑玻璃工业碳达峰。

国外平板玻璃行业碳中和技术路径跟踪研究

近年来,气候变化已经成为当今人类发展共同面临的严峻挑战,开展碳减排行动已成为全球共识。玻璃工业同样面临碳排放的现实问题。围绕国外平板玻璃行业碳中和技术路径的研究及应用现状,开展玻璃行业碳排放现状与碳中和技术路线的分析与研究,掌握碳排放来源,提出实施碳中和的有效路径,有助于推动玻璃行业节能降碳。

碳/玻混杂纤维铺层顺序对其复合材料力学性能的影响

混杂纤维增强复合材料可通过混杂纤维的协调匹配产生协同混杂效应,从而提高复合材料在强度、刚度、性价比等方面的优势。为了研究碳纤维与玻璃纤维铺层顺序对复合材料力学性能的影响,制备5种不同铺层顺序的碳/玻混杂纤维增强复合材料,结合显微组织与拉伸断口分析了纤维铺层顺序对其强度、刚度、应力-应变曲线的影响规律。结果表明:铺层顺序对复合材料的力学性能影响显著,铺层间隔越均匀其增强效果越好,碳纤维或玻璃纤维集中分布于试样中间时均不利于复合材料性能的提升,碳纤维、玻璃纤维单层间隔时其抗拉强度比纯玻璃纤维增强复合材料提高了约60%,3层间隔时其强度略低于纯玻璃纤维增强复合材料;铺层间隔越均匀其层间开裂越集中且断口处纤维单丝拔出长度越大;碳纤维加入后复合材料的刚度大幅度提升,其应力-应曲线出现不同程度的波动,但铺层顺序对复合材料刚度影响甚微。

修复材料与牙体组织力学适配性的研究进展

牙齿作为发挥咀嚼功能的主要器官,可承受无数次功能性接触,这与它的力学性能和组织结构密切相关。牙釉质和牙本质的硬度较高,并且它们具有梯度化的结构,这使得牙齿既能承受咬合力,又不致轻易折裂。当牙体组织缺损时,往往需要全冠修复体来恢复牙齿正常的形态与功能。常用的全冠修复材料有金属材料、陶瓷材料以及最近兴起的聚醚醚酮材料。金属材料在美学方面存在一定劣势,目前在临床上应用相对较少。不同组成成分的陶瓷材料在性能及美学上的表现有所差异,但弹性模量与硬度过高,在力学性能方面都超过了牙体组织,与牙体组织学力学性能不匹配。与此不同,聚醚醚酮材料的弹性模量低于牙体组织,与骨组织相似,但通过纤维增强等方式能够提高它的性能。当修复材料与牙体组织的力学性能并不完全适配时,两者之间的界面往往形成潜在的薄弱环节,最终影响修复的稳定性和长期效果。本文介绍了牙釉质和牙本质的力学性能以及相对应的结构特点,并在此基础上,分析现有修复材料的优势与局限性,进一步探究口腔全冠仿生设计的可能性。

大丝束碳纤维复合材料在风电叶片的应用

大功率风电机组尤其是海上风电大尺寸复合材料叶片对于材料的强度、耐疲劳性能及长期使用可靠性提出了更高的要求,高强度高刚度碳纤维增强复合材料拉挤板材为大尺寸风电叶片主梁结构提供了最佳解决方案。国产低成本大丝束碳纤维生产技术突破为碳纤维增强复合材料风电板材规模化应用奠定了基础,碳纤维/玻璃纤维(碳玻)混杂成型技术、碳纤维/聚氨酯体系拉挤成型技术为风电板材提供了更多可供选择的技术途径。本文结合上海石化48K大丝束碳纤维在风电领域应用研究成果及国内外风电板材新型技术进展,总结了大丝束碳纤维复合材料在风电叶片板材的应用途径。