酸碱双电位滴定法的改进

改进了酸碱双点电位滴定法,导出了不受双点体积差影响的精确计算公式,并对其准确度进行了探讨。改进后的方法用于弱酸HAc、弱碱Na2CO3及油脂酸价的测定实验表明,在一定条件下指示电极电位E和过剩滴定剂浓度的对数1gCB线性关系良好,测定结果令人满意。     

二氧化硅和高岭土杂质对硫铁矿分解磷石膏的影响

:针对磷石膏资源化利用存在问题,提出了一种用硫铁矿分解磷石膏的方法. 为了实现该工艺的工业化利用,探究了磷石膏内二氧化硅和高岭土杂质对分解过程的影响. 利用Factsage7.0热力学软件,计算了FeS-CaSO₄体系在加入二氧化硅或高岭土后的平衡相图,探讨了加入杂质后可能发生的副反应. 进行了杂质对分解过程影响的实验,并对产品进行SO₃分析及XRD表征. 研究结果表明,SiO₂或高岭土的加入使得FeS和CaSO₄在低温区就能发生反应,提高了反应体系的脱硫率,促进了硫酸钙的分解,并且杂质含量越高,硫酸钙分解率越高. 该研究结果有利于硫铁矿还原分解磷石膏制备硫酸工艺的推广应用.     

煤泥水中高岭土颗粒表面荷电特性研究

煤泥水中高岭土颗粒表面电负性是其难以沉降的主要原因.采用电泳法研究了pH值、搅拌强度、浸泡时间、阳离子浓度与种类对高岭土颗粒表面Zeta电位的影响规律及不同矿物之间的相互作用.结果表明,搅拌使高岭土颗粒表面Zeta电位增大;Zeta电位随pH值增大和浸泡时间的延长先减小后增大,在pH值约为8及浸泡2d时均达到最小值;不同阳离子改变高岭土颗粒表面Zeta电位能力顺序为Al 3+>Ca2+>Mg2+>Na+;不同矿物颗粒间因互凝作用会增大颗粒表面的Zeta电位;FTIR分析表明,悬浮液中离子在高岭土颗粒表面的吸附及表面Si-O,Al-O及Al-OH基团的变化是其颗粒表面Zeta电位变化的内在原因.     

酸碱双点电位滴定法的研究

探讨了影响酸碱双点电位滴定法的准确度和主要因素,并在此基础上改进了原方法。     

酸碱双点电位滴定方法的改进

提出了一种减少滴定误差新的酸碱双点电位滴定方法，运用于极弱酸极弱碱的滴定。     

离子交换—酸碱滴定法测定富马酸其钠盐混合物各组分的含量

基于富马酸、富马酸一钠、富马酸二钠在无水乙醇中溶解度的差异，探讨了用离子交换－酸碱滴定法测定富马酸及其钠盐混合物各组分含量的方法。     

复杂酸碱滴定体系可检性判别的通用方法

本文导出可用于计算含任意组份、任意元酸、碱、盐体系滴定过程各等当点pH值、pH-V曲线上各等当点处切线斜率dpH/dV及滴定终点误差TE的通用公式,提出进行电算的通用算法程序.应用本方法可迅速判定给定物系酸碱滴定分析的可行性,指导酸碱滴定分析方案的制定.     

酸碱双点电位滴定法的研究

探讨了影响酸碱双点电位滴定法的准确度的主要因素,并在此基础上改进了原方法．     

微波辐射改性对废旧胶粉表面性能的影响

采用微波辐射法改性胶粉,用苯乙烯对其进行溶胀,并通过平衡溶胀率、接触角、衰减全反射红外光谱及扫描电镜等研究微波改性对胶粉的交联度、表面润湿性、化学结构、表面形貌等的影响。结果表明,微波法打断了胶粉中部分S—S和C—S键,使得胶粉交联度降低,易于被苯乙烯溶胀;另外,微波辐射使得胶粉表面发生氧化,极性基团增多,因此使胶粉表面亲水性提高。     

电子的碱性与物质的酸碱性质

本文对YCAHOBИЧ的酸碱理论作进一步探讨,认为:电子是一种碱,不仅给出电子对的是碱,给出电子的也是碱;同样的,得到电子的是酸(不仅得到共用电子对的是酸)。从电子的赋存状态和其得失或共用来看物质的酸碱属性,具有普遍意义。氧化还原反应与络合反应可以看作广义酸碱反应之一种。本文还用此观点讨论了一些单质和化合物的酸碱性质。     

二氧化碳辐射特性分析与计算

用宽带k分布模型的传统模型和改进模型计算了CO2要辐射带的g-k分布并与逐线计算结果进行对比.结果表明,随温度升高,气体的吸收系数增大,并且由改进模型计算的结果相对较好,与逐线计算的结果更为接近.分别用指数宽谱带模型、宽带k分布的传统模型与改进模型计算了CO2各谱带在不同温度、不同行程长度下的发射率,并与逐线计算结果比...     

Bio-leaching effects of Leptospirillum ferriphilum on the surface chemical properties of pyrite

Leptospirillum ferriphilum cultured using different energy sources (either soluble ferrous ion or pyrite) changed the surface properties of pyrite.Cell adsorption,zeta-potential,hydrophobicty,FT-IR spectra and surface morphology were investigated.Adhesion of bacterial cells to the pyrite surface is a fast process.Furthermore,the adsorption of cells grown in pyrite is greater than of cells grown in soluble ferrous ion.The Iso-Electric Point (IEP) of pyrite treated with L.ferriphilum approaches that of the cells thcmselves.The contact angle of the pyrite surface was observed to decrease due to the surface formation of some hydrophilic substances during bio-leaching.Changes in pyrite surface properties after bacterial treatment support the idea that ferric ion plays an important role and that indirect bio-oxidation is the principal mechanism of pyrite bio-leaching.     

激光强化处理参数对轧辊表面性能的影响

通过试验，研究了激光功率、光斑直径、扫描速度、搭接量和合金粉含量等激光处理工艺参数对轧辊表面性能的影响，结果表明，轧辊表面经激光淬火处理后。性能稳定，耐磨性和抗疲劳性均有所提高，达到了生产要求．     

Analysis on tribological properties of potentially new friction material with response surface method

The tribological properties of newly developed friction material were evaluated by statistical analysis of the major affecting factors.The material for investigation was non-metallic friction material synergistically reinforced with aramid fibre and CaSO 4 whisker,which was developed for hoisting applications in coal mine.The response surface method(RSM)was employed to analyze the material performances affected by the independent and interactive effect of the factors under the normal working condition and severe working condition,respectively.Results showed that under the normal working condition,the newly developed material exhibited stable tribological properties which were insensitive to the test conditions.While under the severe working condition,the sliding velocity was the most dominant factor affecting the friction coefficient.Additionally,compared to the commercially available material,the modified material showed superior wear resistance and thermal stability.     

Simulation of the interaction of methane,carbon dioxide and coal

Gas adsorption has an important influence on gas flow in a coal body. Research on the characteristics of coal and gas adsorption is the theoretical basis for studying gas flow in coal. In this paper, the interaction between methane, carbon dioxide and surface molecules of anthracite was simulated using the quantum chemistry method. Adsorption energy and adsorption configurations of different quantities of gas molecules absorbed on the coal surface were calculated. The results show that adsorption between coal and the two kinds of gas molecules is a physical adsorption process and there is an optimal configuration. Gas molecules are more easily adsorbed in the hydroxyl-containing side chain, while it is difficult for them to be adsorbed at the position of the benzene ring. Besides, carbon dioxide molecules are more readily adsorbed on the coal surface than methane molecules. The findings have an important significance in revealing the nature of gas adsorption in coal.     

Size-dependent elastic properties of thin films: surface anisotropy and surface bonding

Surface eigenstress and eigendisplacement models were used to investigate the surface stress,surface relaxation and surface elasticity of thin films with different surface orientations.Molecular dynamics simulations and first-principles calculations were conducted on face-centered cubic Au films with the focus on relaxation induced nonlinear initial deformation.The simulation results verify the theoretical predictions of the size dependency of surface energy density and surface stress,and the nonlinear scaling law of the size-dependent Young’s modulus of thin films.The mechanism of the size-dependent behaviors was further explored at the atomic bonding level with the charge density field.The Au atomic bonding at surfaces is enhanced compared to its interior counterpart and therefore the nominal Young’s modulus of the Au thin films is larger when the film thickness is smaller.     

羟基氟硅油表面酸/碱性质的表征

采用反气相色谱法，选择8种已知酸碱性质的探针分子，以净保留时间tN和表面自由能参数（γi^○ ,γi^○-）为指标，表征羟基氟硅油是一种两性偏酸的物质，以于用酸碱理论探讨羟基氟硅油控制氟硅橡胶／白炭黑体系的“结构化效应”及其补强机理的研究和开发以羟基氟硅油为原料研制羟基对端氟硅像胶粘合剂具有一定的指导意义。     

Zn2+掺杂TiO2纳米粉体的结构特性及光催化活性

利用酸催化的Sol-gel法制备纯的和不同掺杂量的Zn2 掺杂TiO2纳米粉体,并用XRD、BET、XPS、SPS等技术对样品进行表征.考察Zn2 掺杂量和焙烧温度对样品的光催化降解亚甲基蓝活性、相结构、晶粒尺寸和表面织构特性的影响,并结合表面光电性质和表面组成等探讨Zn2 掺杂对纳米TiO2光催化活性的影响机制.结果表明:适量掺杂Zn2 可以提高纳米TiO2的光催化活性;当Zn2 掺杂量为0.75%,焙烧温度为500℃时,制备的Zn2 掺杂TiO2纳米粉体的光催化活性最佳.Zn2 掺杂TiO2纳米粉体的光催化活性的提高应归功于Zn2 掺杂促进了光生电子和空穴的分离,抑制相变和晶粒长大从而增强光生e-/h 的氧化还原能力,增加表面羟基,改善样品表面的吸光性能.