PAN基炭薄膜形成过程的研究

以溶液聚合法所制得的约50μm厚的PAN薄膜为基膜成功地制备出PAN基炭薄膜。通过测量试样的重量、尺寸、分子中各基团的振动形式，膜表面结构与组分分布和序态结构的变化，对炭化行为进行了研究。测试结果表明，薄膜试样在热稳定化后和炭化后的重量损失分别为10％和39％，尺寸收缩率分别为13％和15％左右，PAN基炭股由碳、氮和氧三种基本元素所组成。随着热解温度的提高，PAN线型结构转变成具有萘啶环大共轭结构的梯形高聚物，继而生成相互交联而成的共轭碳的类石墨芳香族六角网状层面结构。     

POD基炭薄膜形成过程的研究

制备出了ＰＯＤ（聚恶二唑）薄膜,测定了ＰＯＤ薄膜试样在热解炭化期间的化学结构和重量变化,研究了ＰＯＤ薄膜的炭行为。随着热解温度的提高,ＰＯＤ大分子在氧二氮茂环处发生断裂,形成具有共轭腈基苯的化合物。新生成的〉Ｃ＝Ｎ－和－Ｎ＝Ｃ＝Ｏ基团继续进行反应,其中－Ｎ＝Ｃ＝Ｏ基团通过耦合反应生成炭化二亚胺（－Ｎ＝Ｃ＝Ｎ－）;再经分子链环化转变成具有吡啶型大共轭结构的多环化合物,继而稠环芳构化生成类石墨芳香族六     

RUPTURE OF THIN MICROPOLAR LIQUID FILM ON A CYLINDER

The dynamic rupture process of a thin liquid film on a cylinder has been analyzed by investigating the stability to finite amplitude disturbances. The dynamics of the liquid film is formulated using the balance equations including a body force term due to van der Waals attractions. The governing equation for the film thickness was solved by finite difference method as part of an initial value problem for spatial periodic boundary conditions. A decrease in the cylinder radius will induce a stronger lateral capillary force and thus will accelerate the rupture process. The rupture time increases with the material parameter, Δ.     

RUPTURE OF THIN MICROPOLAR LIQUID FILM ON A CYLINDER

The dynamic rupture process of a thin liquid film on a cylinder has been analyzed by investigating the stability to finite amplitude disturbances. The dynamics of the liquid film is formulated using the balance equations including a body force term due to van der Waals attractions. The governing equation for the film thickness was solved by finite difference method as part of an initial value problem for spatial periodic boundary conditions. A decrease in the cylinder radius will induce a stronger lateral capillary force and thus will accelerate the rupture process. The rupture time increases with the material parameter, Δ.     

cdSe_xTe_(1-x)薄膜电极光溶解性能的研究

用循环伏安法对半导体Cdse_xTe_(1-x)薄膜电池的光溶解性能进行了研究。在1mol/L KCl溶液中测量光溶解产物的阴极还原特性,考察了在多硫化钠,多硫化钾及铁氰化钾溶液中的光腐蚀行为。用此方法还研究了薄膜电极表面的光刻蚀过程和pH的影响,并用X射线光电子能谱分析光刻进行不同时间后,电极表面发生的变化。     

南宋涂山窑黑釉瓷釉面光的薄膜干涉

用ＳＥＭ，ＴＥＭ，ＥＳＣＡ和ＥＤＸＡ对釉面闪现彩色色斑和色环的宋代涂山窑黑釉瓷残片进行了分析研究。分析结果表明，釉表面有一层厚度为零点几微米到几微米的薄膜，膜和膜下的釉层具有不同的分相结构和化学组成。釉面闪现色斑和色环是由于光的薄膜干涉。对薄膜的成因作了探讨。     

THERMORADIATION DRYING OF A THIN SURP ACE FILM ON A TRANSLUCENT SUBSTANCE

The paper presents the results of an investiga- tion into thermoradiation drying and film formation of a two-component solution having substantially dif- ferent boiling temperatures of the components, and being applied to a substrate under the conditions of matching the spectral emissive characteristics of the radiator with the spectral thermoradiative properties of the object of drying. The film transmissivity is found to,increase with a decrease in the mass of the solution during drying.     

THERMORADIATION DRYING OF A THIN SURP ACE FILM ON A TRANSLUCENT SUBSTANCE

The paper presents the results of an investiga- tion into thermoradiation drying and film formation of a two-component solution having substantially dif- ferent boiling temperatures of the components, and being applied to a substrate under the conditions of matching the spectral emissive characteristics of the radiator with the spectral thermoradiative properties of the object of drying. The film transmissivity is found to,increase with a decrease in the mass of the solution during drying.     

TiO_2薄膜光催化氧化I~-的研究

采用溶胶 凝胶法 ,在玻璃珠表面涂覆均匀透明的TiO2 薄膜并制成光催化反应器 ,对水溶液中I- 的光催化氧化进行了研究 .比较了光催化剂的活性 ,讨论了I- 的起始浓度、试液的酸度、光照时间与I2 产率的关系 .实验结果表明 :采用锐钛型TiO2 作光催化剂 ( 3L碘化钾溶液所用催化剂量为 4 0 g) ,当 [I- ]=0 .3mol/L ,[H+ ] =3.0mol/L ,光照 8h时 ,I2 的产率达到 4 1 2 6% .     

THE EFFECT OF PARTICLE DILUTION ON WETTING EFFICIENCY AND LIQUID FILM THICKNESS IN SMALL TRICKLE BEDS

Partial wetting in small scale trickle bed reactors results in incorrect determination of intra-particle apparent kinetic parameters as well as in erroneous reactor scale-up. Although a dilution of catalyst particles with inert fines improves the catalyst wetting efficiency, it does not guarantee full external catalyst wetting at all superficial liquid mass velocities. In this work, a method is presented to relate the wetting efficiency obtained at different operating conditions and at different laboratories for diluted and non-diluted beds. Liquid film thickness in diluted and non-diluted beds is estimated. The effect of the operating conditions on partial wetting and liquid film thickness is discussed.     

高温热处理对PI基炭薄膜的影响

研究了在氩气气氛的保护下,PI（聚酰亚胺）基炭薄膜在高温热处理过程中结构转变的过程和试样的若干性能与热处理温度的关系。用激光拉曼光谱和X—射线衍射技术对其样品的结构参数给予了表征。实验表明,在1700℃以前样品纵、横方向处于收缩状态,1700℃至3160℃（终温）则处于伸长状态;而重量变化却在2100℃以前处于减小状态,2100℃以后呈增重状态;电导率由1．03×102S／cm（1000℃）增加到2．1×104S／cm（3160℃）。随着热处理温度的提高．样品表面结构的有序度增加,终温样品十分接近石墨晶体;样品结构参数d002值逐渐减小,Lc值却一直处于增加状态。     

LaNiO_3薄膜材料氧敏性能的研究

采用硝酸盐为原料、柠檬酸为螯合剂的无机盐溶胶 -凝胶 (ISG)法合成LaNiO3系稀土复合氧化物陶瓷薄膜 ,并且对LaNiO3薄膜在高温还原气氛下的结构稳定性及氧敏机理进行了探讨 .为了进一步提高薄膜的氧敏性能 ,对LaNiO3薄膜进行了贵金属Pt掺杂和Ce掺杂改性 ,制备的Pt/Ce/LaNiO3掺杂改性薄膜在较宽的温度范围内 (3 0 0～ 80 0℃ ) ,对氢气和氧气都具有较好的响应速度 ,并且对气氛循环变化的响应具有重复性和一定的抗老化能力     

相分离对SiO2薄膜粗糙度的影响

用氨水做催化剂配制碱溶胶,用盐酸做催化剂配制酸溶胶,在酸、碱混合溶胶中添加聚丙稀酸(PAA)引发相分离,通过添加不同含量的PAA,制备出具有不同粗糙度的透明薄膜,随后经过三甲基氯硅烷(TMCS)修饰,具有疏水性能和不同的疏水效果。     

低温等离子处理对涤纶润湿性能的影响

用氮气对涤纶进行低温等离子处理,明显地改善了其表面的润湿性能。通过对甘油在纤维上的接触角测量,研究了处理器的功率、处理时间以及预处理对接触角的影响。     

LaNiO_3薄膜的制备及其氧敏特性的研究

本文以Ｌａ（ＮＯ_３）_３·６Ｈ_２Ｏ和Ｎｉ（ＮＯ_３）_２·６Ｈ_２Ｏ为配位前驱体,采用柠檬酸为螯合剂,利用溶胶－凝胶法合成了钙钛矿型稀土复合氧化物ＬａＮｉＯ_３薄膜,研究了薄膜的氧敏特性及烧结温度对薄膜氧敏特性的影响。     

蓝宝石衬底上SiO2薄膜的制备与光学性能

以硅单晶为靶材,高纯的Ar和O2气分别为溅射气体和反应气体,采用射频磁控反应溅射法,在蓝宝石衬底上制备了SiO2薄膜,溅射的工艺参数范围是：射频功率为50～100W,样品托背面温度为25～400℃,沉积速率为4～6nm／min。对影响薄膜质量的工艺参数进行了分析,探索出使蓝宝石镀膜后的红外透过率有最大幅度提高的最佳工艺条件。结果表明,所制备的SiO2薄膜与蓝宝石衬底结合牢固;在3～5μm波段对蓝宝石衬底有明显的增透作用。与其它镀膜技术相比,射频磁控反应溅射法可以在较低的温度下制备出SiO2薄膜。     

GROWTH OF A THIN FILM ACCOMPANIED BY CHEMICAL REACTION

Growth of a thin film as a result of mass transfer from a limited fluid pocket has been modeled. The numerical solution of the moving-boundary problem has been obtained by freezing the time-dependent boundary through Landau transformation. Effects of various physico-chemical parameters on the growth of film with time have been presented. Although originally developed for liquid films, the model successfully predicts the experimentally observed qualitative features of the growth of a solid film. This success takes us a step closer to the larger goal of developing a unified model for growth of all kinds of thin films, involving diffusion as the principal mechanism of transport.     

HEAT TRANSFER IN A THIN LIQUID FILM IN THE PRESENCE OF AN ELECTRIC FIELD

Heat transfer enhancement in an evaporating thin liquid film utilizing a electric field under isothermal interfacial condition is presented. A new mathematical model subjected to van der Waals attractive forces, capillary pressure, and an electric field is developed to describe the heat transfer enhancement in the evaporating thin liquid film. The effect of the electrostatic field on the curvature of the thin film, evaporative flux, pressure gradient distribution, heat flux, and heat transfer coefficient in the thin film is presented. The results show that applying an electric field can enhance heat transfer in a thin liquid film significantly. In addition, utilizing electric fields on the evaporating film will be a way to expand the extended meniscus region to attain high heat transfer coefficients and high rates of heat flux.     

电沉积工艺对p-CuSCN薄膜结构及半导体性质的影响

以乙二胺四乙酸二钠(ethylenediamjn tetraacetic acid disodium,EDTA)为鳌合剂,在水溶液络合体系中采用电沉积法制备了CuSCN半导体薄膜,应用电子隧穿成核和表面态热激发机理以及Mott-Schottky曲线分析了沉积电位和温度对薄膜结构和半导体性质的影响.结果表明:室温下,价带电子隧穿产生的电流与表面态空穴热激发电流在同一数量级,表面态空穴热激发电流不随电位改变,价带电子隧穿电流的变化趋势反映了整体电流的变化.随着阴极电位的升高,由于价带电子的隧穿几率变化,晶粒尺寸先减小后增大;半导体空穴浓度减小,p型性质减弱.由于沉积反应受活化能控制,在高温条件下主要表现为晶粒生长,导致晶粒尺寸增大,薄膜致密度降低;同时也使半导体空穴浓度减小,p型性质减弱.     

Pb用量对锆钛酸铅薄膜微观结构和铁电性能的影响

在Pt/Ti/SiO2/Si基片上,通过多次匀胶旋涂-预热处理工艺制备了PbTiO3(PT)无机薄层夹心的锆钛酸铅(lead zirconate titanate,PZT)薄膜,然后经650℃退火处理得到了所需的具有钙钛矿结构的PZT铁电薄膜.用X射线衍射、原子力显微镜表征了PZT铁电薄膜微观结构,并测试铁电性能.结果表明:制备PT层时的Pb用量对得到的PZT铁电薄膜的微观结构和铁电性能有重要影响.当Pb过量15%(摩尔分数)左右时,得到的PZT铁电薄膜不仅晶界清晰,晶粒尺寸分布均匀,具有纯钙钛矿结构,而且铁电性能优异,剩余极化强度Pr=21μC/cm2,矫顽场Ec=37kV/cm.