Oxidation and Reduction Processes During NO x Removal with Corona-Induced Nonthermal Plasma

In this paper, the NO-to-NO ₂ conversion in various gaseous mixtures is experimentally investigated. Streamer coronas are produced with a dc-superimposed high-frequency ac power supply (10–60 kHz). According to NO _x removal experiments in N ₂ +NO _x and N ₂ +O ₂ +NO _x gaseous mixtures, it is supposed that the reverse reaction NO ₂ +ONO+O ₂ may not only limit NO ₂ production in N ₂ +NO _x mixtures, but also increase the energy cost for NO removal. Oxygen could significantly suppress reduction reactions and enhance oxidation processes. The reduction reactions, such as N+NON ₂ +O, induce negligible NO removal provided the O ₂ concentration is larger than 3.6%. With adding H ₂ O into the reactor, the produced NO ₂ per unit removed NO can be significantly reduced due to NO ₂ oxidation. NH ₃ injection could also significantly decrease the produced NO ₂ via NH and NH ₂ - related reduction reactions. Almost 100% of NO ₂ can be removed in gaseous mixtures of N ₂ +O ₂ +H ₂ O+NO ₂ with negligible NO production.     

Protection of immobilized sulfhydryl groups against autooxidation by alterations in their microenvironment

Immobilized sulfhydryl groups were prepared by partial thiolation of NH₂-glass beads. The microenvironment of the immobilized SH groups was varied by different chemical modifications of neighboring NH₂ groups. Introduction of a strong charge in the surroundings of immobilized sulfhydryls results in their dramatic stabilization against autooxidation. This effect is due to the salting of O₂ from the surface microlayer of the thiolated beads.     

脱色阴离子交换剂的再生研究

提出一种新的离子交换剂再生理论，即吸附物的脱附依靠离子交换和络合的协同效应完成．以二价钙离子为再生剂，对糖液脱色用的阴离子交换树脂和阴离子交换纤维进行再生，并与传统的碱性钠盐相比较，研究证明钙离子为再生剂的工艺，具有低成本、无污染的特点．     

Fluoride and lead adsorption on carbon nanotubes

The properties and applications of CNT have been studied extensively since Iijima discovered them in 1991[1,2]. They have exceptional mechanical properties and unique electrical property, highly chemical stability and large specific surface area. Thus far, they have widely potential applications in many fields. They can be used as reinforcing materials in composites[3], field emissions[4], hydrogen storage[5], nanoelectronic components[6], catalyst supports[7], adsorption material and so on.…     

声波团聚净化尿素造粒塔尾气实验研究*

尿素造粒塔大多采用水洗工艺处理尾气粉尘,存在较为严重的细颗粒粉尘溢出和水汽拖尾问题,因此深入探究声波团聚技术在造粒塔尾气处理方面的应用。通过实验研究了声波与喷雾对除尘效率的影响,发现声波单独作用时在3500 Hz达到最佳除尘效率,为74.49%,协同喷雾时2600 Hz即可实现相近的除尘效率,为73.83%。进一步探究其中机理,采用以粒径测试为依据的团聚效率作为评价指标,结果显示,2600 Hz声波与喷雾单独作用时团聚效率分别为30.37%和28.82%,协同作用时团聚效率大幅提升至57.95%。该研究可为后续造粒塔工程改造提供理论与数据支持。     

LBO晶体超光滑表面抛光机理

胶体SiO2抛光LBO晶体获得无损伤的超光滑表面,结合前人对抛光机理的认识,探讨了超光滑表面抛光的材料去除机理,分析了化学机械抛光中的原子级材料去除机理.在此基础上,对胶体SiO2抛光LBO晶体表面材料去除机理和超光滑表面的形成进行了详细的描述,研究抛光液的pH值与材料去除率和表面粗糙度的关系.LBO晶体超光滑表面抛光的材料去除机理是抛光液与晶体表面的活泼原子层发生化学反应形成过渡的软质层,软质层在磨料和抛光盘的作用下很容易被无损伤的去除.酸性条件下,随抛光液pH值的减小抛光材料的去除率增大;抛光液pH值为4时,获得最好的表面粗糙度.     

基于LIBS及时间分辨特征峰的激光除漆机理研究

激光除漆是一种高效、清洁的新型清洗技术,对激光除漆物理过程和机理的研究是该技术发展的关键。基于LIBS技术,测量得到油漆去除过程中等离子体的发光光谱,计算出油漆样品去除前后等离子体的电子密度和温度,研究了油漆中特征元素对应的光谱特征峰强度随时间的变化情况。结果表明,随着激光作用脉冲数量的增加,油漆去除深度逐渐增加,等离子体电子密度和温度在将漆去除干净的最后几个脉冲作用时呈下降趋势。油漆中Ti元素的所对应的特征峰信号持续时间为2个μs,油漆去除前后信号强度呈现跳跃减少,该现象可用于快速、准确、实时的判断油漆去除情况。     

Mild synthesis of a Zn(II) metal organic polymer and its hybrid with activated carbon: Application as antibacterial agent and in water treatment by using sonochemistry: Optimization,kinetic and isotherm study

In this work, a room temperature and short method (30 min) for synthesis of nanosized rod-like metal organic polymer (MOP) has been described. Reaction of 1,4-phenylenedioxy diacetic acid with zinc salt leads to the formation of [Zn(C₁₀H₈O₆)(H₂O)₄]_n and subsequently was loaded on activated carbon following sonication and structurally characterized by FTIR, SEM, EDX and XRD analysis. The combination of this new composite with sonication was applied for rapid and efficient adsorption of Bromocresol Purple (BCP). Effects of initial BCP concentration, mass of adsorbent and sonication time on response were investigated and optimized by central composite design (CCD). Analysis of variation (ANOVA) was adapted to experimental data to find best optimum conditions which was set at 15.22 mg L⁻¹, 2.41 min, 0.02 g and 0.009 mg for initial BCP concentration, sonication time and adsorbent mass, respectively. Conduction of similar experiments at specified condition permit achievement of 98.69% removal percentage. 1,4-phenylenedioxy diacetic acid and Zn(NO3)₂.4H₂O which have applied for preparation of MOP are interesting antibacterial properties and accordingly MOP was screened in vitro for their antibacterial actively against Proteus vulgaris bacteria and experimental results reveal this MOP was able to inhibit growth of the tested bacteria. The experimental data were best fitted by pseudo-second order and Langmuir for kinetic model and the adsorption equilibrium isotherm, respectively.     

Enhanced Exfoliation Effect of Solid Auxiliary Agent On the Synthesis of Biofunctionalized MoS2 Using Grindstone Chemistry

Mass production and commercial availability are prerequisites for the viability and wide application of MoS₂. Here, we demonstrate enhanced grindstone chemistry for a one‐step synthesis of biofunctionalized MoS₂. By adding a SiO₂ auxiliary agent the exfoliation efficiency increases from 16.23% to 58.59% and a rapid and high‐yield exfoliation of MoS₂ is seen. SiO₂ exhibits a fragmentation effect, which reduces the lateral size and facilitates the exfoliation of MoS₂, thus inducing a high‐efficient paradigm in the top‐down fabrication of biofunctionalized MoS₂ nanosheets. The as‐prepared MoS₂‐chitosan (MoS₂‐CS) nanosheets display complete disaggregation and homogeneous dispersion, as well as a high content of chitosan (ca. 20 wt%). As a proof‐of‐concept application, the MoS₂‐CS nanosheets act as a biosorbent for Pb^II removal, exhibiting a good adsorption capacity and recyclability. This green and facile enhanced grindstone chemistry with minimal use of organic solvents and high‐throughput efficiency can be extended to the fabrication of other biocompatible inorganic 2D analogues for a variety of applications.