改性粉煤灰对酸性黑10B的脱色效果

以H2SO4为改性剂对粉煤灰进行活化处理,用活化后的粉煤灰对酸性黑10B水溶性模拟染料废水进行脱色处理.研究了各种反应条件对脱色效果的影响,并对活化机理和吸附机理进行了探讨.结果表明:粉煤灰经质量分数为50%的H2SO4活化后,在染料的初始质量浓度为10 mg/L,灰水质量浓度为12.5 g/L,pH=1～5,反应时间为120 min的条件下,脱色率可达94%以上.说明粉煤灰经改性后,对染料废水有很好的脱色效果,在造纸废水、纺织印染废水的处理上有广泛的应用前景.     

Morphology Control of SrCO3 Crystals using Complexons as Modifiers in the Ethanol-water mixtures

Using SrC12-6H2O and Na2CO3 as the main raw materials and adding different complexons as modifiers with simple co-precipitation method, SrCO3 crystals with distinct morphologies like spherical, bundle-like, overlapping plate-like, hexagonal star-like, dumbbell-like, etc. can be synthesized in the ethanol-water mixtures. The samples were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and Fourier transform infrared spectrograph （FT-IR）. The interrelated effect mechanism is presented in the end. Results show that the modifier carboxyl groups play a significant role in controlling the SrCO3 crystal morphologies, which can alter the crystal growth unit （Sr^2＋） supply mode and induce the crystal formation with the morphologies matching their spatial configurations.     

Investigation of Glasses and Glaze Coats of Composition R2O–RO–Fe2O3(FeO)–Al2O3–B2O3–SiO2 by the EPR Method

The valence state and the coordination environment of the paramagnetic centers of iron ions in glasses and vitreous coats of composition R₂O–RO–Fe₂O₃(FeO)–Al₂O₃–B₂O₃–SiO₂ have been investigated by the EPR method. The tetrahedral and octahedral coordinations of Fe³⁺ ions have been revealed. The character of change in the EPR spectra of the materials studied in the vitreous and vitrocrystalline state has been determined. It is shown that the coordination number of iron ions is dependent on the crystallization processes.     

The effect of an organic eluent modifier and pH on the separation of wheat-storage proteins: Application to the purification of γ-gliadins ofTriticum monococcum L

Summary Reversed-phase, high-pressure liquid chromatography has been used to separate similar protein (γ-gliadin) components from 70% ethanol extracts of endosperm flour from two different accessions of the diploid wheatTriticum monococcum L. The effect of acetonitrile as the organic eluent was compared to acetonitrile: 2-propanol (3:1) at two different pH's. Conditions for maximum resolution of the γ-gliadin components were found to be at pH 7.2 with acetonitrile: 2-propanol (3:1) as the eluent. These conditions allowed the components to be obtained in sufficient purity for further charaterization. The mention of firm names or trade products does not imply that they are endorsed or recommended by the US Department of Agriculture over other firms or similar products not mentioned.     

Fatigue crack propagation and related failure in modified,andhydride-cured epoxy resins

The fatigue crack propagation (FCP) of neat and modified, anhydridecured epoxy resin (EP) was studied in tensile-tensile mode at ambient temperature. As modifiers, liquid carboxyl-terminated acrylonitrile-butadiene (CTBN) and silicon rubber (SI) dispersions were used. The latter modifier in a defined particle size distribution was produced by a special latex technology, whereas the former developed in situ in the EP by phase separation during curing. The dispersion-type morphologies of the EPs were characterized by using polished sections and viewing them in a scanning electron microscope (SEM). The resulting frequency distribution curves were compared with those analyzed from fatigue fracture surfaces. Probable failure mechanisms were also studied by SEM-fractography.Both modifiers improved the resistance to FCP by shifting the curves to higher stress intensity factor ranges (K) in relation to the reference curve determined for the neat EP-matrix. The failure mechanisms, summarized also schematically, differed basically for the various modifiers. According to this, rubber-induced cavitation and shear yielding of the matrix seemed to be dominant for CTBN, which did not affect the principal crack plane. In contrast to this, crack bifurcation, branching and, hence, a forced deviation in the fatigue crack path induced by debonded SI-particles in the EP-matrix were concluded for the SI modifier. The common use of both modifiers yielded a positive synergistic effect due to the superposition of the above failure mechanisms.Dedicated to the 60th birthday of Prof. H. H. Kausch     

基于红外光谱的沥青SBS 含量自动测定方法

为有效检测沥青中SBS( Styrene-Butadiene-Styrene Copolymer) 含量,提出了一种基于红外光谱法测定改性沥青SBS 含量的方法。该方法对比分析SBS 改性剂和基质沥青红外光谱,确定SBS 改性剂特征峰966 成为定量测定沥青SBS 的关键点,引入复化辛普生求积公式求吸收峰峰面积; 依据朗伯-比耳定律,通过最小二乘法拟合出峰面积比与SBS 含量之间关系的标准曲线。最后用辽河石化70#基质沥青制备不同SBS 含量的改性沥青,最终校正样本和测试样本测定的SBS 含量平均误差分别是0． 14%、0． 02%。实验结果表明,该方法相比原有凝胶渗透色谱等试验测定方法具有速度快、精度高、易操做等特点,为今后道路建设工程中及时检测沥青 SBS 含量提供一种科学有效的方法。     

Enantioseparation of novel chiral tetrahedrane-type clusters on an amylose tris (Phenylcarbamate) chiral stationary phase

Summary Amylose tris(phenylcarbamate) (ATPC) coated on a small particle silica gel was prepared. This ATPC chiral stationary phase (ATPC-CSP) was found to be useful for the enantiomeric separation of some novel chiral tetrahedrane-type clusters. Moreover, the influence of mobile phase modifier and of the structure of chiral tetrahedrane-type clusters on the chiral separation and retention were investigated. The results suggest that not only the structure and concentration of alcohol in mobile phase, but also the subtle structural differences in racemates can have a pronounced effect on enantiomeric separation and retention.     

石墨炉原子吸收光谱法测定痕量钒的研究

本文采用石记原子吸收光谱对钒吸收线的特征，普通石墨管和热解石墨管中钒的原子化行为，灰化和原子化条件，基体效应等进行了研究，综合应用基体改进剂，光控升温和解石墨管技术，提高了电热原子吸收测定钒的灵敏度，特征质量为２４ｐｇ／０．００４４Ａ。     

Determination of Total Selenium Content in Cereals and Bakery Products by Flow Injection Hydride Generation Graphite Furnace Atomic Absorption Spectrometry Applying in-situ Trapping on Iridium-Treated Graphite Platforms

A flow injection hydride generation graphite furnace atomic absorption spectrometric (FI-HG-GFAAS) method was applied to the determination of Se in Se-doped and undoped cereals and bakery products. For the purpose of doping, the soils used for the cultivation of the cereals were dosed with Se-doped foliar fertilizers. The samples were dissolved in a mixture of HNO₃ and H₂O₂ solutions using microwave-assisted digestion. The decomposition of H₂Se generated from the sample solutions and the trapping of elemental Se were performed at a temperature of 300°C on an Ir-pretreated integrated graphite platform of a transversally heated graphite atomizer (THGA). For release of the trapped Se within a fairly short atomization time (5s), an atomization temperature of 2200°C was observed to be optimal. The overall efficiency of hydride generation, transport and trapping was 86%.The upper limit of the linear dynamic range of calibration was 10µgL^–1, which corresponds to 0.5µgg^–1 for solid samples. Recovery of the samples spiked with Se^VI solutions was found to be 93±6% on average. The relative standard deviation of the determinations was less than 8%. The limit of detection was found to be 0.06µgL^–1, corresponding to 3ngg^–1 for solid samples. The accuracy of the method was verified with the use of IAEA-155 (whey powder) certified reference material. End-capped THGA tubes resulted in an extension of the linear calibration range compared to that of standard THGAs.The Se content in bakery products made of undoped cereals ranged from 7.7 to 68ngg^–1 (wet weight) in 18 samples, whereas the Se content of the corresponding cereals was found to be below 100ngg^–1 (wet weight). The Se level of cereals grown on soils treated with Se-doped fertilizers ranged from 128 to 1046ngg^–1 (wet weight), and it depended linearly on the Se concentration of the corresponding foliar fertilizer.     

Influence of compatibilization on the mechanical behavior of poly(trimethylene terephthalate)/poly(ethylene-octene) blends

Poly(trimethylene terephthalate) (PTT) based blends toughened with up to 30 wt.% of a partially maleinized poly(ethylene-octene) copolymer (mPEO) were obtained by melt mixing. The blends were composed of two pure amorphous phases and a partially crystalline PEO phase. The rubber modification clearly compatibilized the blends leading to a decrease in the dispersed phase size. The decrease was not enough to attain the brittle-tough transition, but an increase in the shear rate gave rise to an additional decrease in the dispersed phase size and in the interparticle distance (IDc) that led to very high toughness values (15-fold the notched impact strength of the matrix) at rubber contents above 25 wt.%. The critical interparticle distance of the blends was 0.17 μm. A comparison between this IDc and those of PBT/mPEO and PET/mPEO blends was explained in terms of their interfacial tensions.