溶胶—凝胶法制备Fe2O3—Mn2O3—SiO2膜

用溶胶－凝胶法在浮法玻璃上制备了Ｆｅ２Ｏ３－Ｍｎ２Ｏ３－ＳｉＯ２膜。对膜层的形成特性进行了观察。得出了制备良好膜层的工艺参数。对薄膜的微观结构和光谱特性进行了测定。讨论了薄膜中铁与锰的价态和配位状态。     

采用有机改性硅醇盐甲基三乙氧基硅烷制备无支撑孤立膜

采用溶胶-凝胶法,以一种有机改性硅醇盐甲基三乙氧基硅烷(MTES)为先驱体,制备了大尺寸的、厚度可达50-1 000 μm的无支撑孤立膜. 并研究了成膜参数及该溶胶的配制过程对膜的质量的影响. 采用IR分析了孤立膜的膜层结构,采用AFM对膜层表面形貌及粗糙度进行了分析.     

TiOx薄膜电阻稳定性及氧敏特性的研究

分别采用无机盐的水解－沉淀法和醇盐的溶胶－凝胶法两种工艺在Ａｌ２Ｏ３基片上制备ＴｉＯｘ（ｘ＝１－２．０）薄膜,研究了薄膜结构及氧敏特性。结果表明：水解－沉淀法的膜层粒子分布均匀,工艺易控制;溶胶－－凝胶法的膜层粒子更细微,相变温度较低,两种工艺制得的超微粒薄膜都具有很好的电阻－温度稳定性。膜层粒子愈起细化,分布愈均匀,氧敏特性愈高;薄膜厚度与气体检测灵敏度有密切关系,具有最佳膜层厚度值,两种工艺获     

真空离子精饰镀膜技术研究

黄铜基材装饰件表面采用高能级溅射离子镀，镀不锈钢代替电镀钯－镍合金，采用等离子体型阴极弧源－磁控溅射镀技术在不锈钢镀膜表面上镀制TiN/Au透明陶瓷保护膜SiO2,TiO2，并对各膜层的硬度，耐蚀性，耐磨性及相结构进行分析。     

Ag靶弧流对TiN/Ag多层膜结构和性能的影响

采用电弧离子镀技术,通过改变Ag电弧靶的弧流在医用不锈钢基底表面制备TiN/Ag多层膜,分析多层膜的微观结构,测试多层膜的厚度、结合强度和硬度,通过摩擦磨损实验测定多层膜的摩擦系数,研究了不同Ag靶弧流对多层膜结构和性能的影响规律。实验结果表明,在不同Ag靶弧流下,TiN/Ag多层膜有TiN(111)晶面和Ag(111)晶面择优生长。Ag靶弧流在一定程度上影响着多层膜中Ag的结晶度,当弧流为50 A时,Ag的结晶度达到最佳,此时多层膜的结合力最大,为45.33 N;多层膜的硬度达到最小值1 189.4 HV;多层膜的摩擦系数最小,为0.242。Ag靶弧流影响Ag层的结晶度,并且对多层膜的结合强度、硬度和摩擦系数具有明显影响。     

Sol—gel法制备纳米硅碳膜的研究

以长链甲基三甲氧基硅烷〖ＣｎＨ２ｎ＋１Ｓｉ（ＯＣＨ３）〗和正硅酸惭脂（ＴＥＯＳ）身份种有机物为起始原料,用溶胶－产胶法制备也ＳｉＣ膜。初步讨论了溶胶形成过程中水中氢键、酸及碱的作用。利用Ｒａｍａｎ光谱和透射电镜（ＴＥＭ）结合ＸＰＳ等测试方法对制得的膜进行了结构、颗粒尺寸及化学成分等的研究,根据分析和观察结果,膜由颗凿及寸在直径为２ｎｍ－４ｎｍ,长度为２０ｎｍ－４０ｎｍ左右的ＳｉＣ纳米晶须构成,纯度     

溶胶——凝胶法制备TiO2分离膜的研究

本文用溶胶－凝胶法制备了有支撑ＴｉＯ２膜，通过ＸＲＤ，ＴＧ－ＤＴＡ，ＳＥＭ等方法对膜制备过程的物理化学变化进行了分析，并就干燥控制剂（ＤＣＣＡ）烧成制度，以及载体等对膜结构完整性的影响作了探讨。     

溶胶—凝胶法制备TiO2担载超滤膜

为制备完整无缺陷的ＴｉＯ２担载超滤膜,本文采用溶胶－凝胶法的颗粒法制备钛溶胶,考察了制膜液组成,膜厚度以及烧结温度对膜孔结构和性能的影响。结果发现以钛酸丁酯为溶胶前驱物,采用颗粒油,可制备粒径适宜的稳定溶胶。膜的完整性与有机添加剂的量及膜的厚度密切相关,膜的渗透通量和孔径随着烧结温度的升高而增大。本文所制备的氧化钛超滤膜的孔径为１．８－４０ｎｍ,厚度为１．５￣２．０μｍ,纯水渗透性达６．７￣８７．     

玻璃膜制备过程中结构演变的核磁共振研究

采用＾１１Ｂ－ＮＭＲ，＾２９Ｓｉ－ＮＭＲ和ＦＴ－ＩＲ对熔融法和溶胶－凝胶法制备的玻璃膜聚合结构进行了研究。结果表明；两种方法制备的玻璃膜结构中，硼离子以三配位和四配位两种方式存在，且存在多种结构单元，而「ＳｉＯ４」四面体的聚合度则组成中硅含量的增加而提高。     

烧结MgO在SiO2—FeO—CaO与FeS—Cu2S熔体界面区的局部侵蚀

采用坩埚法，借助自行设计的高温Ｘ射线透射影视设备，通过Ｘ射线照像主电视观察，研究了烧结ＭｇＯ材料在炉渣（ＳｉＯ２－ＦｅＯ－ＣａＯ）与冰铜（ＦｅＳ－Ｃｕ２Ｓ）界面区局部优先侵蚀过程。发现：ＭｇＯ材料在渣中ＦｅＯ形成致密的（Ｆｅ，Ｍｇ）Ｏ层，紧邻（Ｆｅ，Ｍｇ）Ｏ层形成渣膜，而界面张力流的存在使渣膜产生运动，促进渣膜层中ＭｇＯ的传质过程，加速ＭｇＯ材料的侵蚀，从而引起ＭｇＯ材料在渣－冰铜界面区局部优先侵     

Ferroelectric Ceramics in the PbMg1/3Nb2/3O3-PbCd1/3Nb2/3O3 System

Solid solutions (1-x)PbMg_1/3Nb_2/3O₃ + xPbCd_1/3Nb_2/3O₃ with x = 0-0.30 are investigated with purpose to work out a capacitor ceramics with good dielectric properties and low sintering temperature. It is found that the perovskite phase forms at sintering near to 980°C and begins to decompose at higher temperatures. When x grows from 0 to 0.30, the Curie temperature linearly grows from -10°C to +25°C, the dielectric permittivity ε_m in the Curie point T_C decreases from 18000 to 6800 and the phase transition becomes more diffused. The dielectric permittivity at room temperature is rather high and the temperature stability is improved. The system is of interest, because it can serve as a base for working out some ceramic materials for capacitors with low sintering temperature, which needs of no special atmosphere at burning.     

3-叠氮甲基-3-甲基氧丁环的合成

以三羟甲基乙烷与碳酸二乙酯为原料,经环化反应合成了3-羟甲基-3-甲基氧丁环(HMM O)。在低温下,HMM O与对甲苯磺酰氯反应生成3-磺酸酯甲基-3-甲基氧丁环(M TM O)。M TM O和叠氮化钠发生叠氮化反应形成叠氮单体3-叠氮甲基-3-甲基氧丁环(AMM O)。三步反应收率分别为76%,96%,85%。用核磁、红外、元素分析和DSC表征了化合物的结构与性能。结构鉴定表明为目标化合物AMM O。     

3-溴甲基-3-甲基氧杂环丁烷的合成

以2,2-二溴甲基丙醇（BBMP）为初始原料,通过与碱发生关环反应生成3-溴甲基-3-甲基氧杂环丁烷（BrMMO）。讨论了碱的种类和用量对BBMP关环产率的影响以及反应体系中碱的浓度、反应温度和反应时间对合成BrMMO产率的影响。通过实验确定的最佳工艺条件为：BBMP与NaOH摩尔比为1.0∶1.1,NaOH醇溶液的质量分数为12%,反应温度为78℃,反应时间为4h时,BrMMO产率为65%。最终产品经元素分析、IR和1HNMR检测确定为BrMMO。该试验工艺简单,原料易得,且溶剂便于回收、污染小。     

Tunable color emission in LaScO3:Bi3+,Tb3+,Eu3+ phosphor

LaScO₃:xBi³⁺,yTb³⁺,zEu³⁺ (x = 0 − 0.04, y = 0 − 0.05, z = 0 − 0.05) phosphors were prepared via high-temperature solid-state reaction. Phase identification and crystal structures of the LaScO₃:xBi³⁺,yTb³⁺,zEu³⁺ phosphors were investigated by X-ray diffraction (XRD). Crystal structure of phosphors was analyzed by Rietveld refinement and transmission electron microscopy (TEM). The luminescent performance of these trichromatic phosphors is investigated by diffuse reflection spectra and photoluminescence. The phenomenon of energy transfer from Bi³⁺ and Tb³⁺ to Eu³⁺ in LaScO₃:xBi³⁺,yTb³⁺,zEu³⁺ phosphors was investigated. By changing the ratio of x, y, and z, trichromatic can be obtained in the LaScO₃ host, including red, green, and blue emission with peak centered at 613, 544, and 428 nm, respectively. Therefore, two kinds of white light-emitting phosphors were obtained, LaScO₃:0.02Bi³⁺,0.05Tb³⁺,zEu³⁺ and LaScO₃:0.02Bi³⁺,0.03Eu³⁺,yTb³⁺. The energy transfer was characterized by decay times of the LaScO₃:xBi³⁺, yTb³⁺, zEu³⁺ phosphors. Moreover absolute internal QY and CIE chromatic coordinates are shown. The potential optical thermometry application of LaScO₃:Bi³⁺,Eu³⁺ was based on the temperature sensitivity of the fluorescence intensity ratio (FIR). The maximum S_a and S_r are 0.118 K⁻¹ (at 473.15 K) and 0.795% K⁻¹ (at 448.15 K), respectively. Hence, the LaScO₃:Bi³⁺,Eu³⁺ phosphor is a good material for optical temperature sensing.     

2,2,3-三氯-3-苯基-3-(3-甲基苯甲酰基)丙腈的合成研究

以苯甲酰氯、四氯化碳、间甲基苯甲酰氰为原料,合成了标题化合物。重点考察了氰化过程中不同原料配比、反应温度、时间、溶剂和催化剂用量对收率的影响。实验结果表明,其最佳反应条件为:n(1,1,2-三氯-2-苯基乙烯)∶n(3-甲基苯甲酰氰)=1∶1.2,二氯甲烷为反应溶剂,3 mmol催化剂三乙胺,室温反应5 h,总收率达80.6%。     

3-溴甲基-3-甲基氧杂环丁烷的合成

以2,2-二溴甲基丙醇(BBMP)为初始原料,通过与碱发生关环反应生成3-溴甲基-3-甲基氧杂环丁烷(BrMMO).讨论了碱的种类和用量对BBMP关环产率的影响以及反应体系中碱的浓度、反应温度和反应时间对合成BrMMO产率的影响.通过实验确定的最佳工艺条件为:BBMP与NaOH摩尔比为1.0∶1.1,NaOH醇溶液的质量分数为12%,反应温度为78℃,反应时间为4 h时,BrMMO产率为65%.最终产品经元素分析、IR和1HNMR检测确定为BrMMO.该试验工艺简单,原料易得,且溶剂便于回收、污染小.     

The Preparation and Crystal Structure of TlMnCl3, TlFeCl3, TlCoCl3 and TlNiCl3

The compounds TlMnCl₃, TlFeCl₃, TlCoCl₃ and TlNiCl₃ were prepared by heating T1C1 with the corresponding transition metal dichloride in an evacuated ampoule. Atomic positions were determined from powder photographs. All four compounds were found to be related to the perovskite type structure. TlMnCl₃ has a cubic structure, space group Pm3m, with a_o = 5.025 Å. The other three compounds are hexagonal, probable space group P6₃mc, with cell dimensions (in Å) a₀ = 6.976 and c₀ = 6.008 for the Fe compound, a₀ = 6.907 and c₀ = 5.981 for the Co compound and a₀ = 6.863 and c₀ = 5.881 for the Ni compound. The three hexagonal compounds are isomorphous. A measureable concentration of basal plane stacking faults was found to occur in TlFeCl₃ and also, to a lesser degree, in TlCoCl_3.     

Ba3Tb(BO3)3:Eu3+的制备与发光性质

采用高温固相法合成了Ba3Tb(BO3)3:Eu3+红色荧光粉,并研究了Ba3Tb(BO3)3:Eu3+的发光特性。Ba3Tb(BO3)3:Eu3+的激发光谱包含250nm～330nm和350nm～400nm的2个宽带,最大峰值位于383nm,可以被紫外-近紫外发光二极管(light-emitting diodes,LED)有效激发。Ba3Tb(BO3)3:Eu3+的发射谱显示出4组发射峰,其主发射峰位于620nm,对应Eu3+的5D0→7F2跃迁;Eu3+掺杂摩尔分数为2%时,Ba3Tb(BO3)3:Eu3+发光亮度最高。经分析发现Ba3Tb(BO3)3:Eu3+存在Tb3+→Eu3+的能量传递。     

Thermal analyses of poly(3-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)

Thermal analyses of poly(3-hydroxybutyrate) (PHB), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(HB–HV)], and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) [P(HB–HHx)] were made with thermogravimetry and differential scanning calorimetry (DSC). In the thermal degradation of PHB, the onset of weight loss occurred at the temperature (°C) given by T_o = 0.75B + 311, where B represents the heating rate (°C/min). The temperature at which the weight-loss rate was at a maximum was T_p = 0.91B + 320, and the temperature at which degradation was completed was T_f = 1.00B + 325. In the thermal degradation of P(HB–HV) (70:30), T_o = 0.96B + 308, T_p = 0.99B + 320, and T_f = 1.09B + 325. In the thermal degradation of P(HB–HHx) (85:15), T_o = 1.11B + 305, T_p = 1.10B + 319, and T_f = 1.16B + 325. The derivative thermogravimetry curves of PHB, P(HB–HV), and P(HB–HHx) confirmed only one weight-loss step change. The incorporation of 30 mol % 3-hydroxyvalerate (HV) and 15 mol % 3-hydroxyhexanoate (HHx) components into the polyester increased the various thermal temperatures T_o, T_p, and T_f relative to those of PHB by 3–12°C (measured at B = 40°C/min). DSC measurements showed that the incorporation of HV and HHx decreased the melting temperature relative to that of PHB by 70°C. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 90–98, 2001