A Novel Approach to Well‐Aligned TiO2 Nanotube Arrays and Their Enhanced Photocatalytic Performances

A simple route has been developed to prepare well‐aligned TiO₂ nanotube arrays, which is based on outward coating of TiO₂ and inward etching of Cu(OH)₂ nanorod templates. Effects of annealing temperature and time on the crystal size and crystallinity of TiO₂ nanotube arrays and photocatalytic activities of TiO₂ nanotube arrays for degradation of Rhodamine B in aqueous solution have been investigated. The results indicate that the TiO₂ nanotube arrays annealed at 500°C for 2 h possessed an enhanced photocatalytic activity in comparison with the TiO₂ nanotube arrays without post heating and commercial anatase TiO₂ nanoparticle film and presented a good life cycle performance. Scale‐up of the process has also been demonstrated. Our work opens a new avenue to fabricate free‐standing TiO₂ nanotube arrays and demonstrates an excellent photocatalytic performance of the anatase TiO₂ nanotube arrays for wastewater treatment. © 2012 American Institute of Chemical Engineers AIChE J, 59: 2134–2144, 2013     

Evaporation of Ethanol-Water Mixture Drop on Horizontal Substrate

This study investigates the evaporation of sessile drop comprising ethanol and water mixture on horizontal poly methyl methacrylate surface. The contact angle (θ) and contact radius (R) of ethanol-water mixture drop are recorded with time, considering the impacts of presence of ethanol. With excess ethanol, the drop evaporation is principally controlled by a phase in which both the contact angle and contact radius are falling. A diffusional model assuming linear relation between contact radius and time is proposed as θ = eR ^?3 + cR ^?1, where e and c denote fitting coefficients. This model correlates with the experimental data.     

可乐废水处理工艺探讨

可乐废水中的污染物主要是原浆和糖。原浆和糖的COD值可达到数万或十万,均和之后的废水COD浓度在2000 mg/L左右,可乐废水有机物含量高,水质水量极不均匀,尤其是废水量随季节的波动大,pH值不稳定。文章中可乐废水主体工艺采用改进后的厌氧—好氧工艺。厌氧系统采用技术改进后的UASB反应器,UASB反应器主要是独特的布水系统和独特的三相分离器以及内循环系统等,由于该UASB反应器设计的负荷参数合理,污泥床层污泥量大,有机物去除效率较高,处理效果稳定。在冬天时不用蒸气加热仍能达到设计的处理效果,运用该UASB反应器进行处理,不消耗氧气和热能,动力消耗少,运行费用较低。     

有机磷阻燃剂的研究进展

通过有机磷阻燃剂在环氧树脂、聚氨酯、聚碳酸酯中应用现状的介绍,综述了近年来国内外有机膦阻燃剂在这些体系中的研究进展,提出了未来应加深对有机磷阻燃剂的机理研究和推广应用。     

2,6-二氯-4-甲基烟腈合成的改进

介绍了标题化合物的合成路线的改进。以乙酰乙酸乙酯和氰乙酰胺为原料,经过环合、氯代两步反应得到目标产物,并经MS和1HNMR对其结构进行了表征。本合成路线反应条件温和,操作方便,收率较高,适合工业化生产。反应总收率80.3%。     

汽车用罩光清漆的工艺技术研究

对生产汽车通用水性罩光清漆的工艺技术进行了研究,重点阐述了该汽车通用罩光清漆的水性丙烯酸聚氨酯分散体的中试合成及水性助剂的选择;该产品无论是用作原厂漆、还是用作修补漆,其VOC含量都低于21%,不含腐蚀性物质,环保节能。通过试验确定最佳工艺条件:润湿剂、消泡剂、增稠剂和水性多功能助剂添加量(质量分数)分别为0.5%、0.5%、0.4%和0.5%。通过对生产工艺条件的研究,汽车罩光清漆的施工应用性能大大提高,为水性罩光清漆的应用推广打下了坚实的基础。     

同心圆一体化微曝氧化沟的工艺设计

文章提出同心圆一体化微曝氧化沟工艺设想,此工艺主体思路是A/A/O微曝氧化沟基础上,改变其沟型结构,将A/A/O微曝氧化沟和沉淀池、污泥回流泵站构成一双层壁筒状池体,氧化沟在外侧,沉淀池在内侧,好氧池的部分墙体与缺氧池共用,紧靠缺氧池外的是厌氧池,厌氧池的部分墙体与缺氧池共用;氧化沟内有水下推进器、曝气微孔;沉淀池有刮泥机,从沉淀池到厌氧池有回流污泥管及回流泵。微曝气系统和共壁设计能提高充氧效率和减少了土建投资与占地面积,运行管理方便,达到了高效除污和投资省的效果。     

以煤沥青为粘结剂制备柱状活性炭的工艺参数优化

传统煤焦油基制备柱状活性炭粘结剂存在成本高、污染严重、质量不稳定等诸多问题,文章将煤沥青和膨化淀粉复配为新型粘结剂,以无烟煤为原料制备柱状活性炭。采取正交试验设计实验方案,研究活化温度、炭化温度、活化时间、炭化时间与水蒸气通量对柱状活性炭强度、碘吸附值、亚甲基蓝吸附值以及收率的影响,并利用热重分析仪考察了粘结剂的热性能。结果表明:制备柱状活性炭的最佳工艺参数为:活化温度850℃,炭化温度600℃,活化时间300 min,炭化时间60 min,水蒸气通量0.2 mL/min,其碘吸附值达到1241.1 mg/g,亚甲基蓝吸附值高达159.5 mg/g,强度为75.2%,收率38.9%,说明新型粘结剂可制备出符合要求的净化用柱状活性炭。     

Surface modification of TPGS-b-(PCL-ran-PGA) nanoparticles with polyethyleneimine as a co-delivery system of TRAIL and endostatin for cervical cancer gene therapy

The efficient delivery of therapeutic genes into cells of interest is a critical challenge to broad application of non-viral vector systems. In this research, a novel TPGS-b-(PCL-ran-PGA) nanoparticle modified with polyethyleneimine was applied to be a vector of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and endostatin for cervical cancer gene therapy. Firstly, a novel biodegradable copolymer, TPGS-b-(PCL-ran-PGA), was synthesized and characterized. The nanoparticles were fabricated by an emulsion/solvent evaporation method and then further modified with polyethyleneimine (PEI) carrying TRAIL and/or endostatin genes. The uptake of pIRES2-EGFP and/or pDsRED nanoparticles by HeLa cells were observed by fluorescence microscopy and confocal laser scanning microscopy. The cell viability of TRAIL/endostatin-loaded nanoparticles in HeLa cells was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay. Severe combined immunodeficient mice carrying HeLa tumor xenografts were treated in groups of six including phosphate-buffered saline control, blank TPGS-b-(PCL-ran-PGA) nanoparticles, blank TPGS-b-(PCL-ran-PGA)/PEI nanoparticles, and three types of gene nanoparticles. The activity was assessed using average increase in survival time, body weight, and solid tumor volume. All the specimens were then prepared as formalin-fixed and paraffin-embedded tissue sections for hematoxylin-eosin staining. The data showed that the nanoparticles could efficiently deliver plasmids into HeLa cells. The cytotoxicity of the HeLa cells was significantly increased by TRAIL/endostatin-loaded nanoparticles when compared with control groups. The use of TPGS in combination with TRAIL and endostatin had synergistic antitumor effects. In conclusion, the TRAIL/endostatin-loaded nanoparticles offer considerable potential as an ideal candidate for in vivo cancer gene delivery.     

Differential Activity of Plasma and Vacuolar Membrane Transporters Contributes to Genotypic Differences in Salinity Tolerance in a Halophyte Species,Chenopodium quinoa

Halophytes species can be used as a highly convenient model system to reveal key ionic and molecular mechanisms that confer salinity tolerance in plants. Earlier, we reported that quinoa (Chenopodium quinoa Willd.), a facultative C3 halophyte species, can efficiently control the activity of slow (SV) and fast (FV) tonoplast channels to match specific growth conditions by ensuring that most of accumulated Na⁺ is safely locked in the vacuole (Bonales-Alatorre et al. (2013) Plant Physiology). This work extends these finding by comparing the properties of tonoplast FV and SV channels in two quinoa genotypes contrasting in their salinity tolerance. The work is complemented by studies of the kinetics of net ion fluxes across the plasma membrane of quinoa leaf mesophyll tissue. Our results suggest that multiple mechanisms contribute towards genotypic differences in salinity tolerance in quinoa. These include: (i) a higher rate of Na⁺ exclusion from leaf mesophyll; (ii) maintenance of low cytosolic Na⁺ levels; (iii) better K⁺ retention in the leaf mesophyll; (iv) a high rate of H⁺ pumping, which increases the ability of mesophyll cells to restore their membrane potential; and (v) the ability to reduce the activity of SV and FV channels under saline conditions. These mechanisms appear to be highly orchestrated, thus enabling the remarkable overall salinity tolerance of quinoa species.