高岭土尾矿对亚甲基蓝的吸附行为的研究

文章探索了高岭土尾矿对亚甲基蓝溶液的吸附性行为,测定了高岭土尾矿的粒度与用量、亚甲基蓝溶液的pH与浓度、吸附时间及吸附温度等因素对亚甲基蓝吸附性能的影响。结果表明：在碱性条件下,高岭土尾矿对亚甲基蓝溶液有较好的吸附能力,亚甲基蓝浓度增加,高岭土尾矿对其脱色率减小,而随着高岭土尾矿用量的增加,则脱色率不断提高。高岭土尾矿对亚甲基蓝的等温吸附服从Freundlich方程式。高岭土尾矿对亚甲基蓝吸附的随时间的增加、温度的升高而增加。通过对这些参数的探索和测定,高岭土尾矿的吸附能力可以达到98%以上,高岭土尾矿能有效除去溶液中的亚甲基蓝。     

基于LOGO!的阿特拉斯空压机控制改造

1引言美国阿特拉斯空压机具有较高的可靠性,其运行噪音低、效率高,在国内厂矿中被广泛应用于动力气源或制氧系统。我公司有4台GA90风冷机和3台GW132水冷机,使用期已超过10年,部分机器的Elektronikon装置出现故障且无法修复,由于是较早期产品,难以找到可完全替代的备     

纳米Cu-TiO2在亲水涂料中的耐老化和抗菌性能研究

通过光催化还原的方法制备了纳米铜基二氧化钛(Cu-TiO2)抗菌剂。使用浸涂方法将素铝箔基片涂敷上含1.4%抗菌剂的面漆抗菌涂层。对抗菌涂层进行加速老化处理,采用接触角仪、金相显微镜、体视显微镜、抗菌实验等测定涂层老化前后的接触角、表面形貌以及抗菌性能的变化。结果表明:含1.4%抗菌剂的抗菌涂层具有优秀的杀菌性能、亲水性能和耐老化性能。老化之前抗菌率达99.9%以上,老化处理后,涂层表面无明显变化,平均抗菌率达到95%以上,同时亲水角保持小于8°。     

环氧改性含磷苯丙防锈乳液的合成

采用常规乳液聚合方法,以环氧树脂改性含有磷酸酯功能单体的苯丙乳液来制备水性防锈乳液。苯乙烯(St)、丙烯酸丁酯(BA)等为共聚单体,引入环氧树脂及具有抗闪蚀功能的磷酸酯功能单体,考察了乳化剂、引发剂、环氧树脂、磷酸酯单体不同用量对乳液及其漆膜的影响,并对乳液的粒径、固含量及漆膜的耐盐水性、附着力等性能进行测试,逐步优化聚合工艺来合成具有高效防锈的新型环氧防锈乳液。研究表明,乳化剂用量、引发剂用量、环氧树脂用量、磷酸酯单体用量分别为单体总量的1.5%、0.6%、7%、3%时,可制得性能较好的水性环氧改性含磷苯丙防锈乳液。     

石墨炉原子吸收法测定橡胶输血胶管铅含量

采用石墨炉原子吸收光谱法（GFAAS）检测橡胶输血胶管浸出液中微量铅的含量。考察了基体改进剂、灰化/原子化温度等因素对测定的影响,建立石墨炉原子吸收光谱法测定橡胶输血胶管中微量铅的方法。结果表明,在选定的最佳仪器条件下检出限为0.19μg/L,回收率为89.4%～105.1%,相对标准偏差为6.16%（n=6）。方法简便快速,重现性好,灵敏度、准确度高。     

典型烃类分子裂解产物分布数值模拟

利用烃类蒸汽热裂解二维工艺数学模型,选择二维模型原料分子中13种典型烃类分子,通过数学模拟考察烃类分子结构和裂解温度对热裂解产物的影响.结果表明:正构烷烃裂解产物中乙烯收率明显大于异构烷烃,且乙烯收率随着烷烃碳数的增加逐渐增加;异构烷烃裂解产物中丙烯收率大于同碳数的正构烷烃,且丙烯收率随碳数增大而显著减少;异构烷烃裂解...     

One-step preparation of Ag nanoparticle–decorated coordination polymer nanobelts and their application for enzymeless H2O2 detection

In this paper, we report on the one-step preparation of Ag nanoparticle (AgNP)-decorated coordination polymer nanobelts, carried out by direct mixing of an aqueous AgNO₃ solution and a N,N-dimethylformamide (DMF) solution of 4,4′-bipyridine (BPD) at room temperature. The construction of an enzymeless H₂O₂ sensor using such nanocomposites with a detection limit of 0.9 μM is also demonstrated.     

Electrosynthesis of Pd/Au hollow cone-like microstructures for electrocatalytic formic acid oxidation

Pd/Au hollow cone-like microstructures (HCMs) have been electrodeposited on indium tin oxide (ITO) using a two-step protocol, which involves the nucleation pulse and succedent constant potential reduction in the presence of metal precursors and polyvinylpyrrolidone (PVP). Scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscope (XPS) were used to characterize the Pd/Au HCMs. The electrochemical results (cyclic voltammetry and chronoamperometry) testify that the Pd/Au HCMs exhibit significantly higher electrocatalytic activity and stability for the oxidation of formic acid than that of Pd/Au solid microhemispheres (SMHs). These attractive features are attributable to the unique hollow structures of Pd/Au with much higher electrochemical active surface areas and the exposure of favorable planes. Our work points to a new path for the preparation of Pd/Au HCMs, which are promising as electrocatalysts in direct formic acid fuel cell (DFAFC).     

A theoretical model for droplet breakup in turbulent dispersions

A theoretical model for the prediction of droplet breakup rate and daughter size distribution in turbulent dispersions has been developed. It considers the breakup contributed by a novel breakup criterion based on surface energy density increase, the droplet surface oscillation from previous collision and the eddies larger than original droplets. The breakup rate and daughter size distribution predicted by this model show a good agreement with the experimental data reported recently.     

Gas–liquid flow in circular microchannel. Part I: Influence of liquid physical properties and channel diameter on flow patterns

This paper presents an experimental investigation on influence of liquid physical properties and channel diameter on gas–liquid flow patterns in horizontal circular microchannels with inner diameters of 302, 496 and 916 μm. Several liquids with different physical properties, i.e. water, ethanol, three sodium carboxymethyl cellulose (CMC) solutions (0.0464%, 0.1262%, 0.2446% CMC) and two sodium dodecyl sulfate (SDS) solutions (0.0608%, 0.2610% SDS) are chosen as working fluid and nitrogen as working gas. By using a high-speed photography system, flow patterns such as bubbly flow, slug and unstable slug flow, churn flow, slug-annular and annular flow are observed and identified on the flow regime maps. The results show that the liquid physical properties (viscosity and surface tension) and channel diameter affect the flow pattern transitions remarkably. Comparison with existing models in literature implies that these transitions cannot be well predicted. As a result, an effort is put into the proposition of a new empirical model taking the effects of channel size and liquid physical properties into account.