碳纤维在某铁矿选矿厂厂房加固中的应用

通过实例对框架结构主、次梁采取粘碳纤维加固进行了结构计算验证,并对碳纤维加固施工工艺和施工要点进行了介绍。     

碳纤维布在水库加固工程中的应用

碳纤维布加固技术是当前比较有效和新颖的一种加固方式,碳纤维布具有非常好的力学性能,甚至能够作为钢筋的替代品在混凝土中使用。我国很多水库建设时间较为久远,运行到今天,水库的结构部分会出现各种问题,需要对其进行加固处理。研究将碳纤维布运用于水库加固工程中,其优势有加固效果好、施工简单、施工质量有所保障、防水和防腐蚀等。所以水库加固工程使用碳纤维布具有良好的效果。然后再以湖北省某水库为例,发现其闸墩和检修平台梁板不符合规范标准,通过利用碳纤维布对该结构进行加固处理,能够达到很好的施工效果,使其满足规范要求。最后提出了碳纤维布在水库加固工程中的施工注意事项,以期达到水库加固的目的。     

浅析碳纤维布加固砌体结构新技术

碳纤维又称碳纤维增强复合材料(Carbon Fiber Reinforced Polymer,简称CFRP)广泛应用混凝土结构加固技术,而粘贴碳纤维布对砌体结构进行加固仍处于试验研究的初始阶段。粘贴碳纤维布加固是提高砌体结构抗剪承载力和延性的非常有效的办法。本文主要介绍碳纤维布加固砌体结构的工作原理,施工步骤,总结了碳纤维布加固技术的优点,通过试验进一步探究碳纤维布在受剪构件中的力学性能。     

碳纤维材料在桥梁工程维修加固中的应用

交通运输行业的发展对桥梁的承载能力提出了更高的要求,桥梁工程维修加固工作也因此受到了重视。碳纤维材料作为一种新型材料,各方面性能都比较突出,在二次加固施工时也比较适用,因此在桥梁维修加固中扮演着重要的角色。文章对碳纤维材料的特点和桥梁工程维修加固修补技术以及碳纤维材料在桥梁工程维修加固中的应用进行研究。     

碳纤维复合材料加固混凝土结构的优越性

介绍了碳纤维复合材料加固混凝土结构具有不破坏原结构,施工方法简便,加固后能使结构满足设计要求等优点。通过对碳纤维复合材料性能特点、力学性能、加固设计方案依据等的论述,指出其在施工方面的优越性。     

碳纤维复合材料在十字河大桥结构加固中的应用

论述了碳纤维复合材料加固技术应用于枣庄市十字河大桥的加固施工过程和关键技术.经静载和动载测试证明该工程加固效果良好,碳纤维复合材料加固技术具有广阔的推广前景.     

碳纤维复合材料加固混凝土结构技术施工优越性

碳纤维复合材料加固混凝土结构具有不破坏原结构,施工方法简便,加固后能使结构满足设计要求等优点.本文通过其性能特点、力学性能、加固设计方案依据等的论述,指出了碳纤维复合材料在施工方面的优越性.     

碳纤维加固技术在室内装修中的应用研究

碳纤维增强材料以其耐高温、耐腐蚀、耐摩擦以及低密度的特点,受到社会各界关注,成为“新材料之王”。在建筑装修方面,碳纤维加固技术比传统加固技术具有施工方便、质量可靠以及节省工期的特点,在装修中有着广阔的发展前景。该文从碳纤维加固技术的原理出发,基于装修帘墙板制作、室内墙体门洞加固、建筑结构改造补强、防水房顶涂层以及耐磨地板修复等方面,系统探讨了碳纤维加固技术在室内装修中的应用现状。通过合理和科学的设计,碳纤维加固技术能够达到室内装修设计的相关要求,提高装修质量和居住品质。最后,基于现存的应用缺陷,从艺术设计、框架加固以及工程修复等方面对碳纤维加固技术在室内装修中的应用进行了展望。     

运用碳纤维片材加固技术对混凝土柱施工质量事故加固修复的工程实例

通过工程实例,对混凝土柱施工中常见的质量事故运用碳纤维技术进行加固处理的方法进行了研究和探讨.     

土木工程中碳纤维复合材料的运用研究

碳纤维复合材料是随着纤维增强材料的一个重要组成部分,碳纤维复合材料对于结构补强加固十分有效,其施工质量高,施工效率高,加固效果和综合效益好,具有轻质高强、可设计性强的特点。因此,对碳纤维复合材料的研究和探索,一直是土木工程中关注的重点内容。     

石墨和碳纤维改性聚酰亚胺复合材料的导热性能

以石墨、碳纤维(CF)、聚酰亚胺(PI)三元复合材料为研究对象,考察了CF体积含量对PI三元复合材料导热性能的影响,并采用了拟二元体系模型探讨了石墨和CF填充PI复合材料的协同效应。结果表明,CF的加入可以提高复合材料的力学性能：拉伸强度呈现先升高后降低的趋势,当CF含量为11.8 %（体积分数,下同）时,拉伸强度可达66.37 MPa;弯曲强度随着CF体积含量的增而增加,当CF含量为24.6 %时,弯曲强度可达103.3 MPa。复合材料热导率呈非线性增长,表明石墨和CF间存在协同效应;当CF含量为34.1 %时,环境扫描电子显微镜分析表明,CF与石墨能很好地搭接,增大了传热面积,复合材料热导率可达0.512 W/(m·K),约是其计算值的2倍。     

Ethylene–(vinyl acetate) copolymer/carbon fiber conductive composite: effect of polymer–filler interaction on its electrical properties

Ethylene–(vinyl acetate) (EVA)/carbon fibre (CF) composites were prepared by changing the content of CF in the composite. To investigate the effect of the interaction between EVA and CF on the electrical properties of the composite, the CF was treated in nitric acid. The interaction between EVA and CF was examined by a solvent-extraction method. It was found that the interaction of EVA with CF was enhanced due to the chemical absorption of EVA on CF. The correlation of CF content, electrical properties and the formation of polymer–filler gel for the composite with oxidized CF was studied. Although the composites filled with treated CF exhibit a slightly higher resistivity than those filled with untreated CF at room temperature, they show the improved electrical properties, including elimination of the negative-temperature-coefficient (NTC) effect, high electrical reproducibility after thermal cycles, and independence of the conductivity on time, which improves the practical applications of positive-temperature-coefficient (PTC) materials. Copyright © 2004 Society of Chemical Industry     

Highly stable Pt nanoparticle catalyst supported by polyphenol‐grafted collagen fiber and its catalytic application in the hydrogenation of olefins

BACKGROUND: Collagen fiber (CF) is a potential biopolymer support for preparing Pt nanoparticle catalyst. Previous work has shown that the interaction between CF and platinum group metals is not strong enough to fully immobilize these metals. Therefore, epigallocatechin‐3‐gallate (EGCG), which contains multiple orthophenolic hydroxyls, was grafted onto the surface of CF in order to enhance the immobilization of Pt nanoparticles on CF. The methods of preparing EGCG‐grafted CF (EGCG‐CF) and EGCG‐CF supported Pt nanoparticle catalyst (Pt‐EGCG‐CF) were optimized. The catalytic activity and selectivity of Pt‐EGCG‐CF for hydrogenation of typical olefins were investigated. RESULTS: Scanning electron microscopy displayed the ordered fibrous morphology of Pt‐EGCG‐CF. The presence of EGCG grafted on the CF surface and the coordinate interaction of EGCG and Pt were confirmed by X‐ray photoelectron spectroscopy analysis. X‐ray diffraction and transmission electron microscopy analyses showed that Pt nanoparticles with diameter 1–3 nm were uniformly dispersed on the outer surface of CF. Hydrogenation of olefins catalyzed by Pt‐EGCG‐CF was conducted under mild conditions. This heterogeneous catalyst exhibited outstanding activity and nearly 100% selectivity for the hydrogenation of C?C double bonds. Moreover, this catalyst presented satisfactory reusability and storage stability in air. CONCLUSION: An efficient method has been established to prepare a highly active, selective and stable Pt nanoparticle catalyst for the hydrogenation of olefins using EGCG‐grafted CF as a bio‐support. Copyright © 2009 Society of Chemical Industry     

炭黑在沥青基短切碳纤维补强天然橡胶中的作用

研究炭黑及沥青基短切碳纤维表面臭氧改性对碳纤维填充天然橡胶(NR)硫化胶物理性能的影响。结果表明:臭氧改性后,碳纤维的涂覆层基本去除且表面粗糙度明显增加;碳纤维/NR复合材料拉伸断面中碳纤维表面光滑且与NR发生明显脱粘,复合材料物理性能较低;填充30份炭黑N330后,碳纤维/NR复合材料物理性能显著提高,炭黑/短纤维/NR复合材料和炭黑/臭氧改性碳纤维/NR复合材料的拉伸强度分别达到18.6和26.9 MPa,较碳纤维单独填充时分别提高了431%和627%;碳纤维与炭黑具有类似的微观结构,炭黑在碳纤维补强NR时起到桥梁作用,从而大大增强了两者间的界面强度。     

Preparation of carbon fiber/Mg-doped nano-hydroxyapatite composites under low temperature by pressureless sintering

In order to protect carbon fibers (CF) from oxidation damage during sintering process, rod-like Mg-doped nano-hydroxyapatite (Mg-nHA) with an increased thermal decomposition temperature and reduced sintering temperature was synthesized by hydrothermal method. The synthesized bone-like Mg-nHA with similar composition and morphology to bone apatite was used as the matrix to prepare CF reinforced Mg-nHA composites (CF/Mg-nHA) at a low temperature of 700 °C by pressureless sintering. The increase of temperature slightly influenced the growth of Mg-nHA prepared by hydrothermal method from 160 °C to 200 °C. The Mg-nHA were short and rod-like in structure with a length of approximate 100 nm. When doping 1% magnesium, the decomposition temperature of Mg-nHA increased by 100 °C compared with that of nHA. This can protect CF from oxidation damage which is often encountered when sintering CF reinforced hydroxyapatite composites at high temperature and enhance reinforcing effects of CF. The bending strength of CF/Mg-nHA with 1 wt% CF was 8.51 MPa, which increased by 19.5% compared with Mg-nHA. Alternatively, the rod-like Mg-nHA was prepared on the surface of CF by electrochemical deposition and Mg-nHA coated CF was used to reinforce Mg-nHA, the coefficient of thermal expansion mismatch between CF and HA matrix could be mitigated. The compressive strength of Mg-nHA coated CF reinforced Mg-nHA (CF/Mg-nHA/Mg-nHA) composites with 0.5% CF sintered at 800 °C were 41.3 ± 1.56 MPa, which was attributed to the improved strengthening effect of CF and the good interface between CF and Mg-nHA matrix.     

Evaluation of an oleic acid water-in-oil-in-water-type multiple emulsion as potential drug carriervia the enteral route

A water-in-oil-in-water (W/O/W) emulsion composed of oleic acid was used as a carrier of carboxyfluorescein (CF)via the enteral route, as a model for future drug transport. The absorption of CF in the small intestine of rats given the emulsion (W/O/W group) was compared with the absorption in a group administered CF alone (CF group), and a surface-active agent in CF solution (MM group). Higher amounts of CF were absorbed in the W/O/W and MM groups than in the CF group. At 120 min, the amount of CF remaining in the intestinal tract was smaller in the MM group than in the W/O/W group. In the early period, CF excretion into bile was higher in the MM group than in the W/O/W group was higher than in the MM group (non-specific). The blood CF level was significantly higher at 240 and 360 min in the W/O/W group than in the other two groups. The highest concentration in lymph was found in the W/O/W group. The W/O/W emulsion was considered superior to the micelles because it maintained a higher blood level of CF over long periods and transferred it to the lymph. This suggests that the W/O/W emulsion is applicable as a drug carriervia the enteral route.     

表面处理对CF/PA66复合材料磨损性能的影响

采用电化学氧化法和氨气法分别对碳纤维(CF)进行表面处理后,用双螺杆挤出机共混造粒和注塑成型制备CF/PA66复合材料,研究了表面处理对CF/PA66复合材料磨损性能的影向。结果表明:随着CF含量的增加,CF/PA66复合材料的耐磨损性能提高;对CF进行表面处理,可提高CF/PA66复合材料的耐磨损性能,氨气法得到的CF/PA66复合材料的耐磨损性能优于电化学氧化法,当添加CF质量分数为15%时,其体积磨损速率比电化学氧化法的约降低48%。     

基于FBG传感器的CF/GF混杂复合材料界面变形研究

利用FBG传感器对采用真空导入模塑工艺制作的CF/GF(Carbon Fiber/Glass Fiber)混杂复合材料在固化成型过程中以及成型后的界面性能进行了检测,此外,为了对比研究混杂复合材料的性能,还检测了CF/CF层和GF/GF层在成型和成型后的应变变化。结果显示:GF/GF、GF/CF和CF/CF复合材料的应变与温度之间存在良好的线性关系,且热膨胀系数的大小顺序为GF/GF层GF/CF层CF/CF层;FBG传感器监测CF/GF混杂复合材料热膨胀系数的转折温度与基体树脂的T_g值(79.09℃)相吻合;CF/GF混杂复合材料在20~120℃范围内升温、降温过程中未发生界面破坏。     

Wet chemical route synthesis of Cr doped CoFe2O4 @rGO nanocomposite for photodegradation of organic effluents present in drinking water

The current work comprises of the fabrication of spinel cobalt ferrite (CF1), and chromium doped cobalt ferrite (CF2) by wet chemical method (co-precipitation). Moreover, the nanocomposite of Cr-doped cobalt ferrite with reduced graphene oxide (CF3) was fabricated by an ultra-sonication method. The structural, functional, morphological, and optical or photocatalytic properties of prepared photocatalysts i.e. CF1, CF2, CF3 were determined by XRD, FT-IR, SEM, and UV–Visible spectroscopy techniques respectively. The present work deals with the removal of an organic dye (Rhodamine B), and a colorless compound (Benzoic acid) from waste water using photocatalysts CF1, CF2, and CF3. Using CF3 (Cr-CoFe₂O₄@rGO) as photocatalytic material, 81% degradation of rhodamine B, and 67% of benzoic acid was observed. CF3 exhibited remarkable photocatalytic degradation activity than CF1 (43%) and CF2 (53%) against rhodamine B. Moreover, CF3 also showed outstanding degradation efficiency (67%) against benzoic acid than pure cobalt ferrite i.e. CF1 (46%). The outstanding removal efficacy of CF3 nanocomposite was due to the 2D structure, high/massive surface area and increased capacity to transport electrons of reduced graphene oxide (rGO).     

Electrical conductivity of carbon fibers/ABS resin composites mixed with carbon blacks

In this article, the electrical conductivity of composites with different ratios of carbon fiber (CF) content to carbon black (CB) content was studied. The CF content is the main factor to determine the resistivity of the composites filled with CF and CB. The conduction mechanism for this kind of composite is discussed. From comparison of the resistivity of the composites filled with CF and CB with that of the composites filled with CF only, it is shown that using CB as a substitute for part of the CF in CF-filled composites can decrease the production cost, but hardly change the conductivity. The optimum substitution amount is 5% when CF content is beyond 10% in the composites. © 1996 John Wiley & Sons, Inc.