负载型非晶态合金催化剂Ni-Fe-Rh-P/CNFs的制备及其催化性能

研究了化学镀Ni-Fe-Rh-P非晶态合金镀层的工艺,考察了镀液成分和工艺参数对沉积速率和镀层质量的影响。利用优化的工艺配方在经过敏化、活化处理后的纳米碳纤维（CNFs）表面沉积了Ni-Fe-Rh-P合金镀层,分别利用能量色散X射线谱（EDS）、X射线衍射仪（XRD）及扫描电子显微镜（SEM）等手段对镀层的成分、结构、形貌进行了表征,采用液相硝基苯催化加氢反应表征了制备催化剂的催化活性。结果表明,利用化学镀技术可以在纳米碳纤维表面负载连续、均匀的Ni-Fe-Rh-P合金镀层,且镀层为非晶态结构;负载型非晶态合金催化剂Ni-Fe-Rh-P/CNFs具有很高的催化活性和良好的循环使用性能。     

金纳米片的制备

采用PDDA作为表面活性剂,用二乙二醇(DEG)来还原氯金酸,制备单晶金纳米片。通过改变种子的类型,得到了边长从几百nm到几μm甚至十几μm的纳米片。采用扫描电子显微镜(SEM)和原子力显微镜(AFM)对纳米片的形貌进行了表征。     

电沉积法合成纳米铂-铱粒子及其电化学性能研究

以碳纤维纸为基底,采用电沉积法分步合成了纳米铂-铱（Pt-Ir）粒子。采用扫描电子显微镜（SEM）、透射电子显微镜（TEM）、X射线能谱（EDS）等物理表征手段对电催化剂的形貌结构及元素组成进行了研究。从生物质来源的乙酰丙酸（LA）出发,以纳米铂-铱粒子为电催化剂,在甲醇相体系中电催化合成2,7-辛二酮。同时,实验结果证明铱元素的引入增强了纳米铂粒子的电化学活性,并降低了铂的使用量,节约了成本。     

采用聚乙二醇200作溶剂合成花状Ni和NiS纳米结构

以聚乙二醇（PEG）200作溶剂，合成了花状Ni和NiS纳米结构。用X射线衍射仪（XRD）和扫描电子显微镜（SEM）对产物进行了表征。实验结果表明：产物形貌均为由交织的纳米片组成的花状Ni和NiS结构，其中纳米片的厚度分别为约10nm和20nm。对溶剂和有机表面活性剂对NiS纳米结构形貌的影响也进行了研究。实验结果表明PEG200在合成花状Ni和NiS纳米结构起着关键性作用。     

铜基板法制备纳米碳纤维薄膜的研究

以乙炔(C2H2)作为碳源,采用化学气相沉积法(CVD)在经过草酸溶液腐蚀的铜基板表面制备出纳米碳纤维薄膜。采用扫描电子显微镜(SEM)和X射线粉末衍射仪(XRD)对产物进行结构与形貌表征,并对碳纤维薄膜进行其在基板上的附着性测试。结果表明,草酸腐蚀时间、化学气相沉积反应时间的变化等因素对纳米碳纤维薄膜的生长与形貌有一定影响。在反应温度为350℃时,铜基板表面制备出了一层均匀的纳米碳纤维薄膜,纤维直径为300~400 nm,薄膜的厚度为20~30μm。制备的纳米碳纤维薄膜对基板有良好的附着性。     

碳包覆铁纳米金属颗粒的制备

以酚醛树脂为碳源,硝酸铁为催化剂大量制备碳包覆铁纳米金属颗粒。利用扫描电子显微镜（SEM）、透射电子显微镜（TEM）、高分辨透射电子显微镜（HRTEM）等方法,分析和表征了产物的微观形貌和结构。结果表明：产物为纳米级的准球形碳一铁核壳结构,由同心碳纳米石墨壳层包覆纳米铁组成。产物外径30～100nm,碳层间距为0．34mm,与石墨层间距非常接近。     

国产T800S级碳纤维表面特性对复合材料界面性能影响研究

对两种国产T800S级碳纤维与进口T800S碳纤维表面特性及其复合材料界面性能的关联性进行了研究。通过扫描电镜（SEM）与原子力显微镜（AFM）对三种碳纤维的表面形貌与粗糙度进行了表征;采用X射线光电子能谱（XPS）对三种碳纤维表面化学官能团比例进行了分峰计算;通过碳纤维表面静态接触角对纤维表面浸润性进行了分析。制备并表征了碳纤维NOL环与单向复合材料的力学性能与微观破坏形貌,通过对比分析确定了影响复合材料界面性能的关键性因素,对复合材料界面性能的进一步提升具有指导意义。     

碳纤维表面处理对层间剪切断裂形貌的影响

用气相氧化法对碳纤维进行表面处理，可使碳纤维复合材料（CFRP）的层间剪切强度（ILSS）提高40％－76％，这归因于纤维表面增加了化学官能团和比表面积，同时，由于碳纤维（CF）与基体之间粘接得到改善，使单向（UD）－CFRP的剪切断裂形貌变为拉剪，这可用扫描电子显微镜（SEM）观察剪断形貌得到证实。     

不同形貌氢氧化镍的可控合成

文章采用溶剂热法成功合成了棒状、管状和球状β-Ni（OH）2,用X射线衍射（XRD）和扫描电子显微镜（SEM）分别对产物的物质结构和形貌进行了表征。以扫描电子显微镜（SEM）为表征手段,考察了实验条件,如反应温度、时间等,对产物形貌的影响,并初步讨论了其形成机理。实验结果表明,在反应温度为130℃时,产物为微米棒,170℃时产物为微米管,反应温度升高至190℃时,产物为由纳米片构筑的球状结构。该合成方法简单、反应条件温和,是合成纳米材料的一种有效方法。     

桉木浆纳/微米和脱脂棉纳米纤维素的形貌分析

用环境扫描电子显微镜和透射电子显微镜表征了桉木浆纳/微米和脱脂棉纳米纤维素的形貌。环境扫描电子显微镜观察桉木浆纳/微米和脱脂棉纳米纤维素表面形貌不同,桉木浆纳/微米纤维素主要呈棒状,长度小于20 μm,直径可达0.377 μm;脱脂棉纳米纤维素主要呈球状,长度小于0.5 μm。利用环境扫描电子显微镜,脱脂棉纳米纤维素超声波破碎后直接观察和再经冷冻干燥后观察表面形貌有一定的差异。透射电子显微镜观察桉木浆纳/微米纤维素和脱脂棉纳米纤维素的长度可达到纳米级。     

高性能碳纤维表面特性及其对浸润性能的影响

以4种不同型号的高性能碳纤维T700、UTS50、T800和IM7为研究对象,采用扫描电子显微镜和原子力显微镜对碳纤维直径、表面形貌和粗糙度进行表征,通过表面/界面张力仪对纤维表面能和树脂体系的表面张力进行分析,利用旋转流变仪对树脂体系的粘度进行测试。最后对碳纤维与不同温度和不同丙酮质量分数的618环氧树脂浸润性能进行测试,以分析纤维表面性能、温度和溶剂质量分数对碳纤维浸润性能的影响。结果表明,升高温度或提高溶剂质量分数有利于降低树脂体系的表面张力和粘度,从而有效改善碳纤维的浸润性能。纤维直径、表面粗糙度和表面能对碳纤维的浸润性能均有一定影响,其中纤维直径是影响浸润速率的主导因素,表面能和表面粗糙度对浸润质量的影响更加显著。     

乙烯基酯树脂固化条件及其复合材料的研究

研究了过氧化二苯甲酰(BPO)、过氧化二异丙苯(DCP)、过氧化苯甲酸叔丁酯(TBPB)3种固化剂对乙烯基酯树脂固化工艺的影响,并根据固化工艺制备出树脂浇铸体及其碳纤维复合材料。采用差示扫描量热(DSC)法研究了不同树脂固化体系的反应放热特性,采用扫描电镜(SEM)分析了浇注体的断面的表面形态。并对浇注体及复合材料进行了力学性能测试和热稳定性表征,结果表明制得的复合材料具有优良的力学性能和热稳定性。     

Accelerated ultraviolet aging study of the Vectran fiber

Aging behavior of Vectran fiber exposed to ultraviolet (UV) radiation was investigated. Vectran fiber was subjected to UV‐accelerated degradation environment. Tensile strength of Vectran fiber was determined at room temperature using a two‐parameter Weibull distribution. The average tensile strength loss was 42.75% when the irradiation time reached 186 h. The surface morphology of the degraded fiber was examined using scanning electron microscopy (SEM) and atomic force microscopy (AFM). X‐ray photoelectron spectroscopy (XPS) and ¹³C‐NMR were used to provide a molecular characterization of fibers. SEM and AFM showed that UV exposure result in microvoids on the surface of fibers. The results of the XPS and ¹³C‐NMR indicated that the UV radiation could lead to chain scission of fiber surface layer. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

The effect of alkalization on the mechanical and water absorption properties of nonwoven kenaf fiber/unsaturated polyester composites produced by resin‐transfer molding

In the present study, mechanical and water absorption properties of the nonwoven kenaf fiber (KF)/unsaturated‐polyester composites manufactured by resin transfer molding were investigated. Nonwoven KF mats with an aerial density of 1350 g/m² were treated with a 6% NaOH solution for 3 h. The influence of the fiber treatment on the properties of the composites was investigated with Fourier transform‐infra red (FTIR), X‐ray photoelectron spectroscopy (XPS), X‐ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscope (AFM), and dynamic contact angle technique (DCAT). Mechanical properties measurements were conducted via determination of flexure and fracture toughness. A general trend was observed whereby alkalized KF composites gave superior mechanical properties compared to as‐received KF composites. The XRD and DCAT results indicated an enhancement of the crystallinity index and surface energy of the alkali‐treated KF. SEM and AFM of the treated KF showed the removal of impurities and a reduction of roughness on the KF surface with alkalization. Water immersion induced a drastic loss of the mechanical properties of the composites albeit better retention of properties was observed in the case of alkalized KF composites. The fracture surfaces were inspected by SEM which confirmed the quality of the interface. POLYM. COMPOS., 37:3516–3526, 2016. © 2015 Society of Plastics Engineers     

Improvement of interfacial properties in bismaleimide composites using functionalized graphene oxide grafted carbon fiber

A hierarchical reinforcement, which was used to improve the interfacial properties of bismaleimide (BMI) composites, was prepared by grafting functionalized graphene oxide (GO) onto a carbon fiber surface. The GO and carbon fibers were first functionalized separately to create interactional functional groups on their surfaces. The grafting process was then realized by an amidation reaction of the amine and acyl chloride function groups formed on GO and carbon fibers, respectively. The surface groups of functionalized GO and carbon fibers were identified by an X‐ray photoelectron spectroscopy (XPS). The resulting reinforcement was further characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM) and dynamic contact angle analysis. Experimental results showed that the functionalized GO were successfully grafted onto the carbon fibers surfaces and significantly increased the surface energy of carbon fibers. The study also indicated that the prepared hierarchical reinforcement could significantly improve the interfacial adhesion of resulting BMI composite. POLYM. ENG. SCI., 58:886–893, 2018. © 2017 Society of Plastics Engineers     

不同方法合成LiNi0．5Mn1．5O4对其形貌及性能影响研究

锰镍酸锂（LiNi0．5Mn1．5O4）作为正极材料,具有良好的循环性能、较高的容量、高而单一的放电平台．因此,近年来成为电池研究的热点。不同的合成方法以及合成条件对镍锰酸锂的形貌及其性能具有极大的影响。本研究分别采用溶剂凝胶法、固相法、熔融盐法方法合成LiNi0．5Mn1．5O4并通过X-射线衍射、扫描电镜（SEM）、循环伏安法电池性能测试对合成产物的组成、结构、形貌和电化学性能进行表征,进而研究影响产品的性能及形貌的诸多因素,并筛选出较为合适的合成条件以提高锂电池正极材料LiNi0．5Mn1．5O4的电化学性能。     

高分散氧化镁粉体的晶格畸变研究

以六水氯化镁为原料,氢氧化钠和氨水为沉淀剂,采用直接沉淀法合成出高分散氢氧化镁粉体;再将前驱物氢氧化镁煅烧后得到高分散氧化镁粉体产品。通过X射线衍射(XRD)和扫描电镜(SEM)对所得产品的分析表征结果表明,氧化镁粉体的微结构中存在晶格畸变,表现为晶格膨胀。随煅烧温度的升高,氧化镁粉体的晶格常数减小,晶格畸变量也减小。     

Influence of oxygen plasma treatment on interfacial properties of poly(p‐phenylene benzobisoxazole) fiber‐reinforced poly(phthalazinone ether sulfone ketone) composite

The influence of oxygen plasma treatment on both surface properties of poly(p‐phenylene benzobisoxazole) (PBO) fibers and interfacial properties of PBO fiber reinforced poly(phthalazinone ether sulfone ketone) (PPESK) composite were investigated. Surface chemical composition, surface roughness, and surface morphologies of PBO fibers were analyzed by X‐ray photoelectron spectroscopy (XPS), Atomic force microscopy (AFM), and scanning electron microscopy (SEM), respectively. Surface free energy of the fibers was characterized by dynamic contact angle analysis (DCAA). The interlaminar shear strength (ILSS) and water absorption of PBO fiber‐reinforced PPESK composite were measured. Fracture mechanisms of the composite were examined by SEM. The results indicated that oxygen plasma treatment significantly improved the interfacial adhesion of PBO fiber‐reinforced PPESK composite by introducing some polar or oxygen‐containing groups to PBO fiber surfaces and by fiber surface roughening. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Effect of treatment pressure on structures and properties of PMIA fiber in supercritical carbon dioxide fluid

The effects of treatment pressure on the structures and properties of PMIA fiber were investigated by Scanning electron microscopy, Dynamic wetting measurements, Fourier transform infrared spectrometry, X‐ray diffraction, thermogravimetric analysis, and mechanical properties test technology in supercritical carbon dioxide. The results indicated that the surface morphology, the water contact angle, the interaction of macromolecules, the crystal structure, the thermal property, and tensile strength of PMIA fibers were changed during supercritical carbon dioxide treatment, particularly the surface morphology and the wettability of fiber changed the most obviously with the increase of treatment pressure. Furthermore, the thermal property and tensile strength of treated PMIA fiber sample were improved in comparison with those of untreated sample. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41756.     

氧化锌/碳复合材料的合成、表征及吸波性能研究

本文先以二水合醋酸锌和氢氧化钠为原料,得到了氧化锌微晶;以合成的氧化锌为前驱物,葡萄糖为碳源,由水热法合成了产物氧化锌/碳(ZnO/C)复合材料。用X射线衍射(XRD),拉曼光谱(RM),扫描电镜(SEM),透射电镜(TEM),热重分析(TG)等,对产物进行了表征,讨论了不同反应条件(添加剂,时间,溶剂)对合成氧化锌/碳微晶的影响,并对产物的微波性能进行了测试。结果表明,所得产物为氧化锌/碳,呈棒状形貌,热稳定性好,并具有优异的吸波性能。在频率为17GHz时,3mm厚度的产物微波吸收达到-12dB。