吡啶环改性石墨相氮化碳光催化还原Cr(VI)的研究

以三聚氰胺和吡啶二羧酸为原料,通过水热合成有机大分子前驱体,设计了吡啶环改性的石墨相氮化碳(x% Py-CN).利用TEM、XRD、XPS、FT-IR、EIS等手段对所得x% Py-CN催化剂进行表征分析.以水中Cr (VI)为目标污染物,考察了x% Py-CN催化剂的光催化还原性能.结果表明,在模拟太阳光照射下,10% Py-CN具有最佳的光催化性能,光照3h对15mg/L Cr (VI)光催化还原率达85%.x% Py-CN催化剂光催化活性提升的原因在于,吡啶环的修饰有效提高了光生电子空穴对的分离效率.此外,重复循环实验表明该催化剂具有良好的稳定性和循环利用能力,具有良好的应用前景.     

基于舵面振荡激励试飞的飞机动特性识别与修正

目的通过试飞的方法,识别飞机的动态特性,包括模态频率、舵面效率、阻尼等,用以修正飞机的动响应分析模型。方法舵面振荡虽然是电传操纵飞机的一种故障情况,但是可以主动地应用于试飞,作为频域激励施加于飞机上,获得飞行状态下飞机的频响特性。通过对比试飞数据和模型分析结果,识别并修正动响应模型的模态频率、舵面效率、阻尼等参数,来建立更接近实际飞机的动响应分析模型。结果舵面振荡激励试飞数据与动响应模型振荡分析的结果在趋势上较为一致,通过对动响应模型参数的识别和修正,提高了动响应模型的准确度。结论舵面振荡激励作为一种频域激励,是飞机地面共振试验(GVT)的补充和发展,可便捷地应用于飞机的试飞试验,从而识别和修正动响应分析模型。     

Model Modification and Application on Carrying Capacity of Relative Resources

Based on the retrospection of researches on carrying capacity, this article reviewed systematically the research progresses on carrying capacity of relative resources （CCRR）. Then the viewpoint was put forward that CCRR is not an appropriate method of appraising the regional sustainability, but a sound way to obtain cognition for coordinating spatial location and flow of population and economy. However, as the most popular computing method of CCRR, the Weighting Linear Sum Model is defective in the random of weight choice and the neglect of matching among different resources. Therefore, this article established the Geometric Model on CCRR based on modifying Weighting Linear Sum Model, which can be used to appraise regions where resources are close matching. Employing the Geometric Model, the article empirically analyzed the population and economic CCRR in Hubei Province from 1978 to 2006. The result indicates that the population in Hubei Province is overloading while the economic carrying capacity is abundant compared to the whole country, and the economic insufficiency restricts the population carrying capacity. In the future, Hubei Province will become one of the core developing zones which are characterized by economic conglomeration.     

白炭黑洗涤水用量影响因素研究

论文对表面改性剂(包括硅烷偶联剂如:A-172、KH-570、CG-550、KH-550等和表面活性剂如:壬基酚聚氧乙烯醚、十六烷基三甲基氯化铵等)和操作条件(反应温度、搅拌转速、pH等)对白炭黑白炭黑洗涤水用量的影响进行了研究,并将实验所得的白炭黑的性能(吸油值、比表面积等)与文献值进行了比较,结果表明壬基酚聚氧乙烯醚在投加量为1.2 g、改性温度在50℃、改性pH在中性或偏弱碱性时硫酸钠含量最低,此时洗涤水用量最少。硅烷偶联剂对产品的理化性能的改性作用要好于表面改性剂,而表面活性剂对洗涤水用量的影响作用大于硅烷偶联剂。     

Zeolite (Na) modified by nano-Fe particles adsorbing phosphate in rainwater runoff

Zeolite (Na) modified by self-synthesized nano-Fe particles was used as infiltration media to adsorb phosphate in rainwater runoff. The adsorption capacities increased up to 75 times that of natural zeolite at a saturated equilibrium phosphate concentration of 0.42 mg/L. The correlation of capacity and material-specific surface area indicated that specific surface area was not the key factor contributing to the capacity improvement. SEM and XRD analysis showed that chemical reaction between Fe and P to form new products like cacoxenite is the main reason for the increased capacity, and that the method of adding metal ions or particles to improve the adsorption capacity for phosphate is feasible.     

Mercury oxidation and adsorption characteristics of potassium permanganate modified lignite semi-coke

The adsorption characteristics of virgin and potassium permanganate modified lignite semi-coke (SC) for gaseous Hg⁰ were investigated in an attempt to produce more effective and lower price adsorbents for the control of elemental mercury emission. Brunauer-Emmett-Teller (BET) measurements, X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to analyze the surface physical and chemical properties of SC, Mn-SC and Mn-H-SC before and after mercury adsorption. The results indicated that potassium permanganate modification had significant influence on the properties of semi-coke, such as the specific surface area, pore structure and surface chemical functional groups. The mercury adsorption efficiency of modified semi-coke was lower than that of SC at low temperature, but much higher at high temperature. Amorphous Mn⁷⁺, Mn⁶⁺ and Mn⁴⁺ on the surface of Mn-SC and Mn-H-SC were the active sites for oxidation and adsorption of gaseous Hg⁰, which oxidized the elemental mercury into Hg²⁺ and captured it. Thermal treatment reduced the average oxidation degree of Mn^x+ on the surface of Mn-SC from 3.80 to 3.46. However, due to the formation of amorphous MnO_x, the surface oxidation active sites for gaseous Hg⁰ increased, which gave Mn-H-SC higher mercury adsorption efficiency than that of Mn-SC at high temperature.     

改性壳聚糖复配FeCl_3处理微污染水

用改性壳聚糖复配无机絮凝剂FeCl3处理微污染水。结果表明:用改性壳聚糖替代壳聚糖,在用量节省约50%时,显著提高了浊度和有机物的去除效果。与单独使用壳聚糖相比,改性壳聚糖、FeCl3、改性壳聚糖复配FeCl3处理微污染水,UV254去除率分别从26%、42.4%、47%提高到68%,浊度去除率分别从52.6%、83.7%、79.7%提高到92.6%。在pH=7,沉降时间10 min等最佳条件下,改性壳聚糖复配FeCl3强化混凝处理微污染水效果优于聚丙烯酰胺。     

环境矿物材料吸附重金属的有机改性研究

环境矿物材料应用在重金属污染治理中越来越受到人们的关注,而通过有机改性可以有效提高其治理效果。结合国内外对环境矿物材料的有机改性研究,综述了应用于重金属污染治理的环境矿物材料有机改性的研究进展,并提出了发展趋势和展望。     

Hydrothermal fabrication of selectively doped organic assisted advanced ZnO nanomaterial for solar driven photocatalysis

Hydrothermal fabrication of selectively doped (Ag⁺ + Pd^3 +) advanced ZnO nanomaterial has been carried out under mild pressure temperature conditions (autogeneous; 150°C). Gluconic acid has been used as a surface modifier to effectively control the particle size and morphology of these ZnO nanoparticles. The experimental parameters were tuned to achieve optimum conditions for the synthesis of selectively doped ZnO nanomaterials with an experimental duration of 4 hr. These selectively doped ZnO nanoparticles were characterized using powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), UV–Vis spectroscopy and scanning electron microscopy (SEM). The solar driven photocatalytic studies have been carried out for organic dyes, i.e., Procion MX-5B dye, Cibacron Brilliant Yellow dye, Indigo Carmine dye, separately and all three mixed, by using gluconic acid modified selectively doped advanced ZnO nanomaterial. The influence of catalyst, its concentration and initial dye concentration resulted in the photocatalytic efficiency of 89% under daylight.     

热态钢渣CO_2改性及热力学性能研究

钢渣是来源于炼钢过程的废弃物,其矿物组成与水泥熟料相似,但钢渣中含有较高的f-Ca O,是限制钢渣在建材领域应用的重要原因。基于此,利用CO2改性技术对钢渣进行了改性处理,并通过热力学分析对改性效果进行了验证。结果表明:热力学理论分析与实验结果具有良好的一致性,CO2作为改性气相对钢渣物相组成具有显著改性效果,改性后钢渣中f-Ca O含量可以降到1%以下。