表面硅烷化铜箔的电化学腐蚀与防护研究

用γ-氨丙基三甲氧基硅烷(γ-APS)溶液对铜箔表面硅烷化处理,采用动电位极化和电化学交流阻抗研究不同pH的γ-氨丙基三甲氧基硅烷溶液自组装铜箔电极在0.1 mol.L^-1NaCl溶液的腐蚀防护效果,采用扫描电子显微镜观察γ-氨丙基三甲氧基硅烷自组装膜的表面形貌.结果表明,γ-氨丙基三甲氧基硅烷自组装铜箔有较好的腐蚀防护效果,其中pH=7的γ-氨丙基三甲氧基硅烷溶液自组装膜的抗腐蚀效果最佳.     

盐酸法测定γ-氨丙基三乙氧基硅烷及其修饰的纳米二氧化硅表面氨基

建立了用盐酸乙醇标准溶液非水滴定γ-氨丙基三乙氧基硅烷(APS)偶联剂及其修饰的二氧化硅纳米颗粒表面氨基的方法,探讨了滴定溶剂、指示剂对滴定结果的影响,并用电位滴定法对指示剂的终点进行了确定。实验表明:以乙醇作溶剂、百里酚兰作指示剂时,其准确度较高、精密度较好,对APS偶联剂工业样品(A)的回收率为99.40%~100.8%,RSD为0.1%;对APS修饰的二氧化硅纳米颗粒(B),其回收率为99.45%~102.2%,RSD为0.66%。该方法简便、快速,可作为APS含量及其二氧化硅纳米颗粒表面修饰的氨基含量测定的基本方法和企业生产控制与质量检测的方法,具有良好的应用前景。     

3-氨丙基三乙氧基硅烷对溶胶-凝胶法苯乙烯-顺丁烯二酸酐共聚物/SiO_2杂化材料的制备与性能的影响

用３ 氨丙基三乙氧基硅烷（ＡＰＴＥＳ）作为偶联剂，通过溶胶 凝胶（Ｓｏｌ Ｇｅｌ）过程制得两相以共价键结合的透明苯乙烯 顺丁烯二酸酐共聚物／ＳｉＯ２杂化材料．通过ＦＴＩＲ分析等证实了材料有机相与无机相间是以共价键结合的．分析了材料热处理温度和分别用盐酸或氨水作催化剂时对材料溶胶分数的影响、偶联剂及其用量对溶胶 凝胶体系凝胶时间的影响、并研究了杂化材料中无机含量对材料折射率和Ｔｇ的影响     

纳米金/3-氨丙基-三乙氧基硅烷修饰传感器电化学检测NO-2

将3-氨丙基-三乙氧基硅烷（ATS）修饰在玻碳电极表面,再自组装一层纳米金,制备了一种新型NO2^-的电化学传感器。该修饰电极对NO2^-有较好的催化作用。在pH为3时,NO2^-的氧化峰电流与其浓度在5．0×10^-7～1．0×10^-3mol／L范围内呈良好的线性关系,检出限可达2．0×10^-7mol／L。方法具有较高的灵敏度和较好的重现性。     

硅烷化与乙酰化联合衍生化法定性定量分析摇头丸

在摇头丸片剂中 ,有效成分为安非他明( amphetamine)类药物。此毒品除了掺假剂 ,多数还含有糖类作为稀释成分。这些成分的定性定量分析对于确立毒品特性、建立毒品间的区别与关联、进而追踪毒品的来源与走私路线具有重要的法庭科学意义。这一类毒品中 NH基团与 OH基团通常是共存的。在气相色谱分析中 ,为了提高检测灵敏度和改善色谱行为 ,衍生化是十分重要的。而对于这两类基团 ,硅烷化与乙酰化是常用的衍生化方法。本文采用 N-甲基 - N-三甲基硅烷基三氟乙酰胺( MSTFA)和 N-甲基 -双三氟乙酰胺 ( MBTFA)为这两类衍生化试剂的代表 ,…     

水溶性ZnO/氨丙基-硅氧烷量子点的合成与荧光特性

利用溶胶-凝胶法在非水体系中合成出ZnO量子点,并用3-氨丙基三乙氧基硅烷(APTES)对其进行包覆,制得水溶性ZnO/氨丙基-硅氧烷量子点(ZnO-ASQDs)。通过实验确定最佳包覆条件:t=60℃,T=30min,nSi:nZn=1:1,VPEG/Vtotal=1/9。合成的ZnO量子点分别在348与512nm处有2个荧光发射峰,且激发区域较宽(220~360nm)。经过APTES包覆,ZnO量子点荧光发射强度明显增强,同时具有良好的水溶性与荧光稳定性,稳定时间可达60d之久。由Brus公式计算表明,包覆层对ZnO量子点不但改性还起到保护作用,抑制其团聚。经XRD与TEM证实,ZnO-ASQDs具有核壳结构,ZnO核平均粒径为6nm,整体粒径约为20nm。此外,通过调整ZnO核的粒径可制备出不同荧光颜色的ZnO-ASQDs。     

过渡金属表面有机官能团硅烷膜的研究——镍电极表面γ-氨丙基三甲氧基硅烷膜的结构

在镍电极表面制备了γ-氨丙基三甲摒在硅烷膜并对其形成和结构进行了研究 。镍电极表面有机官能团硅烷膜的X射线光电子能谱（XPS）结果表明氮、硅等元素 在电极表面的存在，并且氨基在膜中有若干种存在方式，包括自由氨基和质子化的 氨基。通过对表面增强拉曼散射光谱（SERS）谱图的分析，发现与电极表面作用的 吸附基团硅醇羟基和氨基发生了竞争吸附，它们及其邻近基团的拉曼谱几随着电位 的负称除了相对强度发生变化以外，还发生了一定的位移，这缘于吸咐基团吸附的 量和吸附取向随电极电位发生了变化并形成的更为复杂的界面结构；氨基不同存在 方式之间也会随之发生转变，这一结果与X射线光电子能谱分析的结果相符合。原 子力显微镜（AFM）结果表明镍电极表面的有机官能团硅烷膜呈现为一种较规则的 多孔结构。     

氨丙基官能化HMS介孔分子筛的合成及表征

沿S0I0路径,以十六胺为模板剂,以3-氨丙基三乙氧基硅烷为有机硅源,通过与TEOS共水解沉淀合成了氨丙基官能化HMS介孔分子筛.采用粉末X-射线衍射分析、N2吸/脱附、扫描电镜分析、高分辨透射电镜分析、傅立叶变换红外分析以及元素分析等表征手段,对所合成的材料进行表征.氨丙基官能化HMS介孔分子筛具有worm-like孔道结构,且较为均一的孔径分布.研究了前体硅源中3-氨丙基三乙氧基硅烷含量的变化对氨丙基官能化HMS介孔分子筛的相结构及织构性能的影响.傅立叶变换红外分析表明,NH2-CH2-CH2-CH2有机基团分布在杂化HMS介孔孔道中.     

阳离子和两性表面活性剂对石英表面润湿性的影响

利用座滴法研究了阳离子表面活性剂十六烷基醚羟丙基季铵盐(C16PC)和两性离子表面活性剂十六烷基醚羟丙基羧酸甜菜碱(C16PB)溶液在石英表面上的润湿性质, 考察了表面活性剂类型及浓度对接触角的影响趋势, 讨论了黏附张力和黏附功的变化规律. 研究发现, 两种表面活性剂在高能的石英表面的吸附造成石英-水的界面自由能(γsl)增大. C16PB通过弱相互作用随机吸附到石英表面, 其增大γsl的能力与降低表面张力(γ1g)的能力相当, 接触角(θ)随浓度变化不大. C16PC 随体相浓度增大能够在石英表面通过静电作用形成定向排列的单分子层, 而后在临界胶束浓度(cmc)附近形成双层结构, 接触角随浓度变化的趋势可分为4个区域, 并通过一个极大值.     

采用XPS与接触角法研究氟聚合物表面结构与性能

本文采用接触角和变角XPS方法对FA共聚物的表面能、 表面微相结构做了进一步的研究.     

椭圆法测量接触角

接触角在胶体与表面化学、矿物浮选、洗涤和油气开采等领域是一项重要的物性参数.本文提出椭圆法计算接触角的公式,在接触角小于90°时,利用测量出的椭圆的长轴和短轴半径和油-水-固接触点的坐标计算接触角;在接触角大于90°时,只需在椭圆轮廓线上选择两点,测量四个数据计算接触角,该方法计算公式比较简单,便于推广应用.本文提出将...     

溶液表面吸附实验的再讨论

In the solution adsorption experiment, different adsorption mode has been observed for aqueous ethanol and aqueous n-butanol, respectively. However, it is difficult to make an adjustment by the profiles of σ-c relationship. Choosing the experimental conditions improperly will give wrong results. Since there is no consistency between the Gibbs adsorption isotherm and Langmuir adsorption isotherm, the experimental data should not be fitted by using any algebraic equations or physical models. The data fitting for this experiment should be carried out according to the following steps:fitting the σ-lnc curve manually, making it monotonic and smooth; retrieving more data from this fitting curve, and re-plotting the σ-lnc curve; calculating the first derivatives at these data points (i.e., (∂σ/∂lnc)_T); calculating surface adsorptions by Gibbs adsorption isotherm, Γ=-(∂σ/∂lnc)_T/RT. As for the calculation of the cross-section area for the solute molecule, the effect of concentration of bulk solution (i.e., c) on the surface molecular density should be taken into account.     

Modified Langmuir Isotherm for the Description of Cluster Adsorption on Surface Lyophilic Centers

An adsorption isotherm that generalizes the Langmuir equation for the cluster adsorption of several interacting molecules at one center is proposed. In the case of the adsorption of water molecules at surface hydroxyl groups on modified silica it was shown that the energy and structure characteristics of such a system, determined by the ab initio method, agree with the experimental data and lead to satisfactory agreement with the parameters of the proposed isotherm. __________ Translated from Teoreticheskaya i Eksperimental'naya Khimiya, Vol. 41, No. 5, pp. 283–289, September–October, 2005.     

利用等离子体技术研究聚苯乙烯表面的接枝聚合反应

用O₂等离子体对聚苯乙烯(PS)进行预处理, 再用Ar等离子体引发N-乙烯基吡咯烷酮(NVP)在其表面接枝聚合. 通过接触角(CA)及表面自由能(SE)分析, 探讨了O₂等离子体预处理条件对PS表面自由能的影响, 确定了预处理的最佳条件. 通过衰减全反射红外光谱(ATR-FTIR)、X射线光电子能谱(XPS)和动态接触角(DCA)分析, 比较了O₂等离子体预处理前后和接枝聚合前后PS的表面组成及表面性能, 实验结果表明, 利用等离子体技术能成功地将NVP接枝聚合于PS表面, 接枝聚合后的PS表面由于极性高分子链和粗糙度的增加, 亲水性增强, 水滴易在其表面铺展. 由于接枝聚合后PS表面的高分子链在水中发生重构, 使后退角降低幅度较大, 接触角滞后现象明显.     

氨基功能化纳米Fe3O4磁性高分子吸附剂对废水中Cr(VI)的吸附研究

采用分散聚合法通过共聚、开环反应, 对纳米Fe3O4进行表面功能化修饰, 得到富含NH2官能团的纳米磁性高分子复合材料. 通过透射电镜(TEM)、振动样品磁强计(VSM)、热重差热分析(TGA)、X射线衍射(XRD)、红外光谱(IR)等对其进行表征, 着重研究了其作为吸附剂对Cr(VI)的吸附性能. 结果表明: 该吸附剂对Cr(VI)的吸附能在10 min内达到平衡; 废水溶液pH值能显著影响吸附剂对Cr(VI)的吸附效果, pH为2.5时效果最佳. 废水中Cr(VI)的初始浓度、吸附时间、温度等因素对吸附效果均有不同程度的影响. 结合相应pH值下Cr(VI)的形态分布, 探讨了这种新型材料对Cr(VI)的吸附机理. 结果表明: 其吸附机理及吸附容量与废水中Cr(VI)的离子形式有关; 吸附过程以离子交换与静电引力为主. 等温吸附数据符合Langmuir模型, T＝308 K, pH＝2.5, V＝40 mL时, 吸附剂的饱和吸附容量qm＝25.58 mg/g. 吸附为吸热过程, 焓变ΔH＝8.64 kJ/mol.     

Contact Angle Measurement for Dispersed Microspheres Using Scanning Confocal Microscopy

Abstract

Scanning confocal microscopy was used for contact angle measurement of individual microspheres. The measurements were carried out by using different laser‐scanned layers of the particle floating on the air–water interface. The ratio of the diameter for the cross‐section of the protruded area of the particle at the air–water interface to the actual diameter of the particle is used for contact angle measurements. Two systems, i.e., glass and polystyrene microspheres with diameters of 3–10 and 6 µm, respectively, with water were used for this investigation (this size range of particles are most relevant to inhalation applications). Using the developed methodology, contact angles of 27° and 41° were measured (with water) for glass and polystyrene particles, respectively. The theoretical error in contact angle measurement for the developed methodology is determined to be generally about 1° with a maximum of 3° for contact angle of particles ranging from 2 to 24 µm in size; the experimental error was 4–6°. The contact angles of glass and polystyrene particles were compared to those obtained from pendant drop method and confirmed.     

Adsorption of SO2 on alumina

The adsorption of SO₂ on alumina used in the aluminium industry, the so-called smelter-grade alumina, was studied in the temperature range 15–120°C. It was found that at temperatures lower than 40°C, sulphur dioxide was bonded to alumina reversibly by physical forces, and the adsorption could be described satisfactorily by the Langmuir adsorption isotherm. The heat of adsorption was estimated to be −33 kJ mol⁻¹. At temperatures ranging from 80°C to 120°C, which prevail in dry scrubbers in the aluminium industry, the heat of adsorption was determined to be −56 kJ mol⁻¹. When SO₂ was adsorbed at temperatures higher than 80°C, about 30 % of the SO₂ could not be desorbed even if the samples were heated up to 250°C. In the presence of SO₂ and oxygen, the formation of sulphate was observed at temperatures above 90°C.     

低温等离子体处理聚酯(PET)表面润湿性与表面结构的研究

研究了O₂、N₂、He、Ar、H₂和CH₄气体低温等离子体改性聚酯(PET)的表面润湿性与表面结构的关系.用已知表面张力的液体测定接触角,作Zisman曲线,求得试样的临界表面张力γ_c;并按扩展的Fowkes式计算试样的表面张力γ_s及其三组分值γ_s^a(色散力)、γ_s^c(偶极矩力)和γ(氢键力),发现经O₂、N₂、He和Ar等离子体短时间处理的聚酯表面自由能显著增大,表面润湿性增强,主要是聚酯表面张力的氢键力成分的贡献,X射线光电子能谱分析表明,这是由于聚酯表面含氧或含氮极性基团增加所致.     

High Pressure Adsorption Data of Methane, Nitrogen, Carbon Dioxide and their Binary and Ternary Mixtures on Activated Carbon

Adsorption equilibria of the gases CH₄, N₂, and CO₂ and their binary and ternary mixtures on activated carbon Norit R1 Extra have been measured in the pressure range 0 P 6 MPa at T = 298 K. Pure gas adsorption equilibria were measured gravimetrically. Coadsorption data of the three binary mixtures CH₄/N₂, CH₄/CO₂, and CO₂/N₂ were obtained by the volume-gravimetric method. Isotherms of five ternary mixtures CH₄/CO₂/N₂ were measured using the volumetric-chromatographic method. First, we present in a short overview the method and procedure of measurement. In a second part, the measured data of pressures, surface excess amounts adsorbed and absolute amounts adsorbed are presented and analyzed. In the last part of the paper the resulting pure gas adsorption data are correlated using a generalized dual-site Langmuir isotherm. Mixture adsorption can be predicted by this model using only pure component parameters with fair accuracy. Results are presented and discussed in several tables and figures.