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41.
研究了商用竹炭和改性竹炭对含铅废水的吸附处理的实验条件及效果。结果表明,对一定质量浓度及一定量含铅废水处理时,只要条件和吸附剂竹炭的投放量合适,铅的去除率均可达99.9%以上。以我国饮用水卫生标准中铅含量≤0.05mg/L为标准,根据废水中铅的含量,给出了吸附处理所需吸附剂投料量的估算方法和实验验证结果,为竹炭在含铅废水处理中的应用提供理论依据。 相似文献
42.
竹炭负载氧空位型BiOI/BiOCl复合光催化剂脱硝机理 《燃料化学学报》2017,45(12):1522-1528
以竹炭为载体,采用溶剂热法制备了氧空位(OV)型BiOI/BiOCl光催化剂,考察了温度和光照强度对其催化脱硝性能的影响,采用SEM、XPS、XRD、PL、Uv-vis等表征方法研究了该复合光催化剂上的脱硝机理。结果表明,在氙灯功率500 W、温度30℃时,最佳脱硝效率可达73%。氧空位改性可以增大竹炭的比表面积和孔容,提高其吸附能力,同时使C=O双键和-COO形式的酸性官能团分解为C-O官能团;OV改性还增加了光催化活性位点,减少了电子空穴对复合概率,从而提高了对NO的光催化降解效率。 相似文献
43.
Philippa L. Ascough Craig J. Sturrock Michael I. Bird 《Isotopes in environmental and health studies》2013,49(1):64-77
We present the results of a study testing the response of two saprophytic white-rot fungi species, Pleurotus pulmonarius and Coriolus versicolor, to charred biomass (charcoal) as a growth substrate. We used a combination of optical microscopy, scanning electron microscopy, elemental abundance measurements, and isotope ratio mass spectrometry (13C and 15N) to investigate fungal colonisation of control and incubated samples of Scots Pine (Pinus sylvestris) wood, and charcoal from the same species produced at 300 °C and 400 °C. Both species of fungi colonise the surface and interior of wood and charcoals over time periods of less than 70 days; however, distinctly different growth forms are evident between the exterior and interior of the charcoal substrate, with hyphal penetration concentrated along lines of structural weakness. Although the fungi were able to degrade and metabolise the pine wood, charcoal does not form a readily available source of fungal nutrients at least for these species under the conditions used in this study. 相似文献
44.
Jing Sun Chun‐Liang Yi Ru‐Song Zhao Xia Wang Wen‐Qiang Jiang Xi‐Kui Wang 《Journal of separation science》2012,35(20):2781-2786
A sensitive and efficient analytical method for triclosan (TCS) determination in water, which involves enrichment with bamboo‐activated charcoal and detection with HPLC‐ESI‐MS, was developed. The influence of several operational parameters, including the eluant and its volume, the flow rate, the volume andacidity of the sample, and the amount of bamboo‐activated charcoal, were investigated and optimized. Under the optimum conditions, linearity of the method was observed in the range of 0.02–20 μg/L, with correlation coefficients (r2) >0.9990. The limit of detection was 0.002 μg/L based on the ratio of chromatographic signal to baseline noise (S/N = 3). The spiked recoveries of TCS in real water samples were achieved in the range of 97.6–112.5%. The proposed method was applied to analyze TCS in real aqueous samples. All the surface water samples collected in Xiaoqing River had detectable levels of TCS with concentrations of 42–197 ng/L. 相似文献
45.
Due to the different sources of charcoals, there are significant differences in their properties. In order to study the catalytic effect of different charcoals to nitrobenzene (NB), we selected nine charcoal-sources to prepare nine charcoals with different properties. The experiments showed that NB could be rapidly reduced by sulfides in the presence of all charcoals. The surface area normalized reduction rate constants of NB increased with H/C and (O+N)/C ratio of charcoals increasing. The difference of catalytic effect for nine charcoals was mainly due to their different species and content of surface functional groups and original organic matter. Based on the theoretical calculation and experimental results, the reaction mechanism of NB catalyzed by charcoal in sulfides solution was analyzed. Some active surface functional groups and original organic matter of charcoals were regarded as the active sites and played an important role in catalyzing the reduction of NB by accelerating the transfer of electrons from sulfides to NB. 相似文献
46.
通过对现行初中化学教材中燃烧条件探究实验的理性分析,以学生已有的生活经验和化学知识为基础,选择学生所熟知的可燃物--纸条和木炭作实验物品,对燃烧条件探究实验进行了绿色化改进。从根本上解决了教材实验的污染问题,将氧气、二氧化碳的实验室制法与性质实验及一氧化碳的可燃性等前后几部分教学内容紧紧地联系在一起,降低了学生的学习难度,培养了学生的创新意识,降低了实验成本,提高了教学的有效性。 相似文献
47.
众所周知,石墨烯片(GS)和碳纳米管是能源转化和储存应用中有效的催化剂. 然而,过渡金属基氮(N)掺杂的体系中经常形成GS和碳纳米管的复合物,使得该体系内的构效关系研究变得十分困难. 为了可控制备出含有理想物种的催化剂,作者尝试通过利用氮对碳纳米管生长的效应调节生成产物的形貌. 本文中,作者采用一步法制备了一系列Fe-N共掺杂的GS、GS/竹节碳纳米管(BCNTs)复合物及BCNTs催化剂. 为了评估碳形貌对催化剂性能的影响,作者采用氧气还原反应(ORR)及二氧化碳还原反应(CO2RR)作为模型反应. 电化学测试结果表明,所有的样品当中仅含BCNTs的催化剂表现出最好的ORR活性(起始电位Eonset = 1.02 VRHE)及CO2RR活性(CO生成法拉第效率FECO = 91.1%,-0.6 VRHE). 进一步的研究表明,优异的活性与独特的BCNTs中存在的缺陷、较大的比表面积、高含量的吡啶N及FeNx相关. 该工作加深了作者对形貌相关的ORR及CO2RR过程的认识和理解. 相似文献
48.
设计一个将中药有效成分提取、含量测定、抗氧化性能研究等集于一体,针对中药特色专业开设的综合实验。该实验以毛竹竹叶为原料,对竹叶总黄酮提取工艺参数进行考察。最佳工艺参数为:乙醇浓度为70%,料液比为1∶25,提取时间为2.0 h,提取温度为80℃时,总黄酮提取率可达2.24 mg/g,并进一步研究了竹叶黄酮的抗氧化性能。本实验涉及无机化学、有机化学中的提取理论知识,分析化学中数据处理方法及仪器分析中紫外分光光度计的使用。在锻炼了学生动手操作能力的基础上,又提高了学生对实验结果进行分析、评价的综合能力。 相似文献
49.
Krittamet Phothong Chaiyot Tangsathitkulchai Panuwat Lawtae 《Molecules (Basel, Switzerland)》2021,26(18)
Pore development and the formation of oxygen functional groups were studied for activated carbon prepared from bamboo (Bambusa bambos) using a two-step activation with CO2, as functions of carbonization temperature and activation conditions (time and temperature). Results show that activated carbon produced from bamboo contains mostly micropores in the pore size range of 0.65 to 1.4 nm. All porous properties of activated carbons increased with the increase in the activation temperature over the range from 850 to 950 °C, but decreased in the temperature range of 950 to 1000 °C, due principally to the merging of neighboring pores. The increase in the activation time also increased the porous properties linearly from 60 to 90 min, which then dropped from 90 to 120 min. It was found that the carbonization temperature played an important role in determining the number and distribution of active sites for CO2 gasification during the activation process. Empirical equations were proposed to conveniently predict all important porous properties of the prepared activated carbons in terms of carbonization temperature and activation conditions. Oxygen functional groups formed during the carbonization and activation steps of activated carbon synthesis and their contents were dependent on the preparation conditions employed. Using Boehm’s titration technique, only phenolic and carboxylic groups were detected for the acid functional groups in both the chars and activated carbons in varying amounts. Empirical correlations were also developed to estimate the total contents of the acid and basic groups in activated carbons in terms of the carbonization temperature, activation time and temperature. 相似文献
50.
铁/活性炭催化剂上费-托合成反应产物分布的非Anderson-Schulz-Flory特性 总被引:6,自引:1,他引:6
在浆态反应釜中研究了铁/活性炭催化剂上费-托合成(Fischer-Tropschsynthesis,FTS)反应产物分布和链增长几率(Anderson-Schulz-Flory(ASF)链增长几率和本征链增长几率).产物分布通常在C1处和C2处偏离ASF分布,呈现C1处偏高而C2处偏低的情况.本征链增长几率的研究结果表明,以活性炭为载体的铁基费-托合成催化剂上存在烯烃的再吸附二次反应,使产物分布偏离ASF分布.铁/活性炭催化剂上同时伴随水煤气变换(watergasshift,WGS)反应.XRD检测到铁/活性炭催化剂上存在FexC和Fe3O4两种物相. 相似文献