太平天国侍王府壁画表面修复材料的原位无损FTIR分析

太平天国侍王府壁画是中国南方壁画的典型代表,具有重要的历史、文化和艺术价值。历史上曾对多幅壁画进行过化学保护,部分壁画表面形成了一定厚度的有机物涂层,分析研究壁画保护修复材料成分对于文物保护具有重要的理论和现实意义。由于文物的珍贵性与不可再生性,原位无损分析技术的研究和应用是未来文物分析的发展趋势,基于便携红外光谱仪的反射红外光谱技术是对文物表面材质较为理想的无损分析手段。利用反射傅里叶变换红外(FTIR)光谱对侍王府壁画的地仗层和表面修复材料涂层进行了现场原位无损分析,这在我国古代壁画及其保护修复材料分析中属首次。首先测试了无涂层壁画白色背景位置反射FTIR光谱,并与标准无机矿物光谱比对确定了壁画地仗层成分主要为方解石和生石膏。在此基础上,分析了无涂层和有涂层壁画表面的红外反射特性及地仗层化学成分对表面涂层反射FTIR光谱测试的影响,探讨了应用Kramers-Kronig(K-K)变换处理数据的可行性,确定了K-K变换的应用范围,分析了壁画涂层K-K变换后反射光谱与衰减全反射(ATR)光谱的差异,并通过显微ATR FTIR光谱和热裂解气相色谱质谱联用(Py-GC/MS)技术分析验证了原位反射FTIR光谱测试结果的可靠性,扫描电子显微镜(SEM)测量了涂层厚度,证明不同厚度涂层均能得到可解析的高质量反射FTIR光谱。最终确定侍王府壁画曾使用过聚醋酸乙烯酯、聚二甲基硅氧烷和三甲树脂三种高分子材料进行过表面加固,并得出壁画保存现状和修复材料及涂层厚度有较大关系。证明了基于反射模式的FTIR光谱技术能准确有效地获取文物表面有机物和部分无机物成分信息。该方法对表面有机涂层尤为敏感,是壁画类文物较为理想的无损分析方法,在壁画保护研究领域具有十分广阔的应用前景。同时,该研究弥补了我国壁画类文物表面有机物原位无损分析的不足,为该领域研究提供了一条新思路。     

钛表面FHAP涂层的电沉积制备及其FTIR特征研究

在含有Ca2+,PO3-₄和F-的电解液中,用电化学恒电流方法,在工作电流为0.9 mA温度为60 ℃的条件下沉积60 min,在医用钛(Ti)表面上制得含氟羟基磷灰石(FHAP)涂层。采用扫描电镜(SEM)、能量弥散X射线谱(EDS)、X射线衍射(XRD)对涂层进行表征,用傅里叶变换红外光谱(FTIR)考察了氟离子的引入对涂层构象和生物活性的影响。结果表明：氟部分取代磷灰石中的羟基,FHAP晶格常数变小,涂层相貌由疏松的微米级的菊花瓣状变化为致密的纳米级的尖锥状。FTIR分析表明,涂层中羟基的伸缩和弯曲振动模式的对称性发生了改变,模拟体液浸泡后涂层覆盖碳磷灰石,涂层生物活性良好。     

射频功率对辉光放电聚合物结构和性能的影响

采用辉光放电技术,利用三倍频射频电源制备了不同功率下的辉光放电聚合物(GDP)涂层.并对GDP涂层进行了傅里叶变换红外吸收光谱(FT-IR)和元素分析仪表征,讨论了功率变化对其内部结构的影响.利用热重法(TG)表征了GDP涂层在30—650 ℃范围内的热稳定性.结果表明:随着射频功率的提高,GDP涂层的沉积速率增大;SP³CH₃和联结甲基的乙烯基强度明显减小,SP³CH₂, SP²CH_{2 关键词： GDP涂层 红外吸收谱 热稳定性 射频功率}     

壳聚糖/SrHAP复合涂层的制备及其FTIR特征分析

在含有Sr2+,Ca2+,PO3-₄和壳聚糖(CHI)的电沉积液中,用恒电流沉积法,在医用纯钛(Ti)表面上得到壳聚糖/掺锶羟基磷灰石(SrHAP)复合涂层。采用扫描电镜(SEM)、能量弥散X射线谱(EDS)、X射线衍射(XRD)对涂层进行检测,用傅里叶变换红外光谱(FTIR)考察了壳聚糖和锶离子的掺杂对HAP涂层构象和生物活性的影响。结果表明：锶部分取代磷灰石中的钙,表面形貌由疏松的针状变为较致密的片状。FTIR分析表明,涂层中出现了典型的amideⅠ和amideⅡ的壳聚糖振动峰,则CHI与SrHAP杂化良好;模拟生理液浸泡后表面覆盖有球状类骨磷灰石,则涂层具备较好的生物活性。塔菲尔测试表明,复合涂层使得Ti表面的抗生理腐蚀性显著提高。     

Si,Al对激光熔覆MoFeCrTiW高熵合金涂层组织性能的影响

为了提高材料表面的耐磨性和高温抗氧化性,利用激光熔覆技术在Q235钢表面制备了MoFeCrTiW高熵合金涂层,并采用X射线衍射仪(XRD)、扫描电镜(SEM)和磨损试验机等研究了Si,Al添加对高熵合金涂层组织、相结构、耐磨性和高温抗氧化性能的影响。结果表明:激光熔覆MoFeCrTiW高熵合金涂层组织为等轴晶,单独添加等物质的量的Si或Al时,涂层分别为共晶组织或树枝晶,同时添加等物质的量的Si和Al时,涂层组织为细小的等轴晶。各高熵合金涂层的主体相均为BCC相,随着Si,Al的添加,BCC相的晶格常数减小。添加等物质的量的Al有助于抑制涂层中金属间化合物的形成,使涂层耐磨性降低;添加等物质的量的Si则会形成含Si的金属间化合物和一些未知相,提高涂层耐磨性。激光熔覆MoFeCrTiW高熵合金涂层在800℃的抗氧化性较高,Si、Al的添加可使涂层的高温抗氧化性进一步提高。     

非金属基体表面涂层质量检测方法研究

为研发新型的涂层检测方法,本文在分析和研究现阶段涂层质量检测技术的基础上,通过对输电线路绝缘子RTV涂层施涂质量的抽检实验,提出一种新型且适用于非金属基体表面涂层质量的检测方法——敲击测声法,用于基体为陶瓷、玻璃等高硬度材料,涂层为橡胶等低硬度材料的质量检测,可以保证在不损伤被测涂层的情况下检测涂层厚度、均匀度等质量指标。当基体与涂层有较明显硬度差别时,通过相同力度敲击被测涂层表面,检测返回的声强峰值(即分贝数值),判断非金属基体表面涂层质量的差异,并在检测软件Wensn Sound Link界面实时显示检测数据的变化,直观地反映检测结果。此方法对航天、电力、机械制造等多个领域的涂层检测具有良好的推广应用价值。     

基于角系数跟踪反射能量研究太空中空心圆柱体温度分布

利用角系数跟踪反射能量求得辐射传递因子,探讨太空中太阳入射下、热控涂层对空心圆柱体温度分布的影响.使用有限差分法离散圆柱坐标系下三维稳态导热方程,考虑辐射-导热边界条件,用Patankar线性化方法将边界条件线性化,用点迭代法来求解名义上的线性化方程组从而得到空心圆柱体的温度分布.热控涂层表面的辐射特性用一组矩形谱带来近似.本文的研究方法对太空航天器件温度分布的精确数值求解具有参考价值.     

TiN对Co基合金激光熔覆层组织与性能的影响

采用5 kW CO2激光器在低碳钢表面熔覆Co基合金涂层及TiN/Co基合金复合涂层,研究了两种涂层的组织、显微硬度以及滑动磨损性能。结果表明,Co基合金涂层主要组成相为-γCo,-εCo,Cr23C6等,TiN/Co基合金复合涂层组成相为-γCo,-εCo,Cr23C6,TiN和TiC等。Co基合金涂层由发达的-γCo枝晶和其间共晶组织所组成,TiN/Co基合金涂层典型组织为等轴固溶体以及细小的共晶组织。TiN对熔覆层的组织有显著的改善作用,促使其组织细化,树枝晶向等轴晶转化,同时可显著提高Co基合金涂层的显微硬度及耐磨性能。     

SHS等离子喷涂制备FeAl2O4-Al2O3-Fe纳米复合涂层的研究

利用SHS等离子喷涂技术,将经过机械团聚法制备的Fe2O3-Al复合粉体送入等离子焰流,沉积出厚度约为400 μm的复合涂层.利用XRD,SEM 和TEM等检测手段对涂层的成分和组织进行了分析,测定了涂层的显微硬度、断裂韧性以及耐磨性.结果表明涂层为具有纳米结构的FeAl2O4-Al2O3-Fe纳米复合组织;涂层的显微硬度为HV100g870;断裂韧性是普通Al2O3涂层的2倍;无润滑磨损的耐磨性是普通Al2O3涂层的2.5倍.     

SHS等离子喷涂制备FeAl2O4-Al2O3-Fe纳米复合涂层的研究

利用SHS等离子喷涂技术，将经过机械团聚法制备的Fe₂O₃-Al复合粉体送入等离子焰流，沉积出厚度约为400 μm的复合涂层.利用XRD，SEM 和TEM等检测手段对涂层的成分和组织进行了分析，测定了涂层的显微硬度、断裂韧性以及耐磨性.结果表明涂层为具有纳米结构的FeAl₂O₄-Al₂O₃-Fe纳米复合组织；涂层的显微硬度为HV_100g870；断裂韧性是普通Al₂O₃涂层的2倍；无润滑磨损的耐磨性是普通Al₂O₃涂层的2.5倍. 关键词： SHS等离子喷涂 纳米涂层 断裂韧性     

Minimization of low-temperature microbending losses in initially curved tightly jacketed double-coated optical fibres

Thermally induced microbending losses in initially curved tightly jacketed double-coated optical fibres at low temperature are investigated. The initial deflections are described by a more general formula. The deflections in an initially curved fibre increase gradually with increasing thermally induced compressive axial force, and result in an increase of microbending loss. In order to minimize such a microbending loss, the Young's modulus and Poisson's ratio of the primary coating should be increased. The best value of the Poisson's ratio of the primary coating is 0.5. On the other hand, the thickness of the primary coating, the Young's modulus and effective thermal expansion coefficient of the secondary coating, and the thickness, Young's modulus and effective thermal expansion coefficient of the jacket should be decreased. These results are compared to those of double-coated optical fibres. Thermally induced lateral pressure in the glass fibre can also produce microbending loss. When the effects of axial force and lateral pressure on the microbending losses are both considered, the optimum selection of polymeric coatings is to let the lateral pressure be less than zero, and the magnitude of lateral pressure and the ratio of the final-initial deflection be as small as possible. When the material properties of polymeric coatings and their thicknesses are selected, there are two ways to achieve the optimum design.     

Design of double-coated optical fibers to minimize long-term hydrostatic-pressure-induced microbending losses

The design of double-coated optical fibers to minimize long-term hydrostatic-pressure-induced microbending losses is investigated. Microbending loss in these fibers is dominated by compressive radial stress at the interface between the glass fiber and the primary coating, which is a function of the material properties of the polymeric coatings and their thickness. To minimize long-term hydrostatic-pressure-induced microbending losses, one should decrease the Young's modulus and Poisson ratio of the primary coating but increase the radius, Young's modulus, Poisson ratio, and relaxation time of the secondary coating. Alternatively, the radius and relaxation time of the primary coating have their optimum values.     

激光对光学薄膜加热过程的数值分析

采用“交替隐型算法”对光学薄膜中的加热过程进行了数值分析,求解得到了薄膜中的二维温度场,并给出一些计算实便。     

双波段激光防护多层反射膜的设计

利用TFCalc膜系设计软件,从理论上对激光防护多层反射膜的光学性能进行了分析。计算了各个膜系的理论投射率曲线。分析了各个因素(如膜系结构、膜层奇偶性、起膜材料)对膜层光学性质的影响。并设计了以ZrO2和SiO2为膜层材料,聚碳酸酯(PC)为基体材料,可以同时防护532nm和1064nm波长激光的1∶2型多层反射薄膜。在532nm和1064nm处的理论透过率都达到了0.01%(光学密度D=4)。并在PC镜片表面镀上23层1∶5型激光反射膜,对理论设计进行验证。对其在400nm~1200nm波长范围内的光学性能进行了测试,测试结果与理论计算值基本吻合。     

霍尔离子源辅助制备长波红外碳化锗增透膜

为了提高锗基底的透过率和环境适应性,镀制了增透保护膜。应用电子枪蒸发加霍尔离子源辅助的方法沉积了碳化锗(Ge_1-xC_x)薄膜。通过固定霍尔离子源参数,控制沉积速率的工艺得到了不同光学常数的碳化锗薄膜。X射线衍射(XRD)测试表明,所制备的碳化锗薄膜在不同的沉积速率下均为无定形结构。采用傅立叶变换红外(FTIR)光谱仪测量了试片的透过率,使用包络法获得了相应工艺条件下的光学常数。在锗基底上双面镀制碳化锗增透膜后,长波红外7.5～11.5 μm波段的平均透过率T_ave>85%。经过环境实验之后的碳化锗膜层完好,证明碳化锗增透膜具有良好的环境适应性。     

线性共蒸法制备非均匀膜的误差特性模拟分析

对双源线性共蒸法制备的非均匀薄膜折射率分布与光学特性的关系作了探讨,并与均匀介质膜的光学特性作了对比;从折射率正变和负变两个方面,讨论了混合介质膜折射率不同变化规律对光学性能带来的影响;讨论了厚度误差和折射率极值误差对非均匀膜光学性能的影响。结果发现折射率变化规律误差主要对非均匀膜的应用波段范围产生影响,而膜层厚度误差和折射率极值误差超过一定值时,将对薄膜光学特性产生重要影响。     

The effect of polymer coatings on switching behavior and cycling durability of Pd/Mg-Ni thin films

Although Pd-capped Mg-Ni alloy switchable mirror thin films have potential applications in smart windows and optical switches, they degrade quickly and cannot be switched after about 150 cycles. This must be improved for practical use. In this study, we tested several polymer coatings on the surface of Pd/Mg₄Ni switchable mirror thin films as a protective membrane and evaluated the optical switching property and durability. The polymer membrane is able to suppress the oxidization of Mg because it has an excellent gas separation characteristic. Polymer coating extended the switching durability of samples to about 1000 cycles. In addition, the transmittance of the thin film in the transparent state is improved by the coating.     

光学薄膜膜厚自动控制系统的研究

介绍了一种利用光电极值法同时控制规整膜系和非规整膜系的方法,利用VC++编写程序实现对光学监控信号的采集、处理及停镀点的自动判断,实现了规整膜系和非规整膜系膜层厚度的自动控制.并利用该膜厚自动控制系统实验制备了规整膜系和非规整膜系多层膜,实验结果表明：利用该系统镀制的薄膜重复性良好,且光谱曲线和理论光谱曲线吻合较好.该系统解决了非规整膜系的监控问题,由计算机控制膜层的停镀点,排除了人的主观因素对薄膜的性能及其制备的重复性产生的影响,提高了薄膜镀制的重复性和成品率.     

Diamond-like carbon coatings for the protection of metallic artefacts: effect on the aesthetic appearance

Plasma-enhanced chemical vapour deposition (PECVD) is an environmentally friendly process used to deposit a variety of nano-structured coatings for the protection or the surface modification of metallic artefacts like the SiO₂-like films that have been successfully tested on ancient silver, bronze and iron artefacts as barriers against aggressive agents. This paper deals with the preliminary results of a wider investigation aimed to the development of eco-sustainable coatings for the protection of Cu and Ag-based artefacts of archaeological and historic interest. Diamond-like carbon (DLC) coatings have been deposited by PECVD in different experimental conditions, in a capacitively coupled asymmetric plasma reactor, placing the substrates either on electrically powered electrode (cathodic mode) or grounded electrode (anodic mode) with and without hydrogen addition in the gas mixture. The final goal is to develop a coating with good protective effectiveness against aggressive atmospheres and contemporarily with negligible effects on the aesthetic appearance of the artefacts. The evaluation of possible colour changes of the surface patinas, due to coating process, was performed by optical microscopy and colorimetric measurements. Furthermore, to evaluate the reversibility of the thin DLC layer, an etching treatment in oxygen plasma has been successfully carried out and optimized. The chemical-physical characterization of the deposited DLC coatings was performed by means of the combined use of micro-Raman and XPS spectroscopies. The results show that the DLC films obtained in the anodic mode, may be proposed as a viable alternative to polymeric coatings for the protection of metallic ancient objects.     

利用氟硅烷提高溶胶-凝胶SiO2增透膜的疏水性

 以正硅酸乙酯为前驱体，氨水为催化剂，采用溶胶 凝胶法制备了二氧化硅增透膜；通过自组装技术，用氟硅烷对膜层进行表面修饰，制得了疏水增透膜，克服了常规增透膜亲水的缺点。采用红外光谱、分光光度计、扫描探针显微镜和静滴接触角测量仪等测试手段分析了薄膜的特性。结果表明：疏水增透膜的峰值透光率为99.7％，疏水角为110°；氟硅烷自组装改性不影响二氧化硅增透膜的光学性能。