磷酸活化石墨的氧还原特性以及用于微生物燃料电池阴极

研究了磷酸活化对石墨电极上氧还原反应的影响,并考察了磷酸活化石墨材料应用于微生物燃料电池阴极的可行性。首先以循环伏安和电化学阻抗谱等电化学方法考察了经磷酸活化的石墨材料的氧还原能力,发现经质量分数为85%磷酸活化12 h后其氧还原能力最强;然后将活化石墨材料应用于微生物燃料电池的阴极,进行极化曲线和功率密度曲线的测定。结果表明,磷酸活化阴极微生物燃料电池的最大功率密度可达7.92 W/m3,为未活化石墨阴极微生物燃料电池的3.4倍;同时进行了电化学比表面积的测定及FTIR的分析测定,结果表明,磷酸活化石墨颗粒的比表面积(7.716m2/g)较未活化颗粒(10.940 m2/g)略有减小,但其表面官能团的数量和种类发生了很大变化。表面官能团的变化可能是导致石墨材料氧还原能力增强及MFCs产电性能提高的重要原因。     

Production and characterization of KOH-activated carbon derived from polychlorinated biphenyl residue generated by the sodium dispersion process

Polychlorinated biphenyl (PCB) residues from the sodium dispersion (SD) process were employed as the raw materials for the production of activated carbon using KOH activation. The pore properties, such as the specific surface area and pore size distribution, were characterized using the Barrett–Joyner–Halenda method and the Horvath–Kawazoe method based on the N₂ adsorption isotherm at 77 K. The activated carbon produced showed similar adsorption capacities and specific surface areas to the commercially available product. The effects of the activation conditions on the porosity of the activated carbon produced were studied. The most significant factor affecting the specific surface proved to be the activation temperature. The activated carbon produced from PCB residues from the high-temperature (423–443 K) SD process had a binary pore size distribution well developed in the 4 nm region and in the micropore region. The pore structure of the carbon produced from PCB residues from the low-temperature (333–393 K) SD process had a wide range of micropores and mesopores.     

Differential reproductive success among subfamilies in queenless honeybee (<Emphasis Type="Italic">Apis mellifera</Emphasis> L.) colonies

With very rare exceptions, queenright worker honeybees (Apis mellifera L.) forego personal reproduction and suppress reproduction by other workers, preferring to rear the queens sons. This is in stark contrast to colonies that have lost their queen and have failed to rear a replacement. Under these conditions workers activate their ovaries and lay many eggs that develop parthenogenetically into a final brood of males (drones) before the colony perishes. Interestingly, not all workers contribute equally to this final generation of drones in queenless colonies. Some subfamilies (workers that share the same father) contribute a disproportionately greater number of offspring than other subfamilies. Here we explore some of the mechanisms behind this reproductive competition among subfamilies. We determined the relative contribution of different subfamilies present in colonies to laying workers, eggs, larvae and pupae by genotyping samples of all life stages using a total of eight microsatellite loci. Our colonies were headed by free-mated queens and comprised 8–17 subfamilies and therefore differed significantly from colonies used in an earlier study investigating the same phenomena where colonies comprised an artificially low number of subfamilies. We show that, first, subfamilies vary in the speed with which they activate their ovaries after queen-loss and, second, that the survival of eggs to the larval stage is unequal among subfamilies suggesting that some subfamilies lay eggs that are more acceptable than others. However, there is no statistically significant difference among subfamilies in the survival of larvae to pupae, indicating that ovary activation and egg survival are the critical components to reproductive competition among subfamilies of queenless honeybee workers.Communicated by R. Page     

用于干式脱污的CaO蒸汽活化实验研究

利用小型活化转炉实验台对以CaO为主要成分的钙基脱污剂在300～650℃的温度范围内进行蒸汽活化处理,结合X射线衍射和压汞仪的分析结果,初步探讨了蒸汽活化的机理.研究表明,蒸汽活化温度在600℃以上时,脱污剂孔隙结构有显著的改善,比孔容积和比表面积有着显著的增加,微孔（＜100nm）的数量大量增加,而低温下蒸汽活化的效果不是十分明显;研究还发现高温下延长活化时间有利于改善脱污剂的孔隙结构.     

Innovatively employing magnetic CuO nanosheet to activate peroxymonosulfate for the treatment of high-salinity organic wastewater

Magnetic CuO nanosheet(Mag-CuO), as a cheap, stable, efficient and easily separated peroxymonosulfate(PMS) activator, was prepared by a simple one-step precipitation method for the removal of organic compounds from salt-containing wastewater.The experiments showed that the removal efficiencies of various organic pollutants including Acid Orange 7, Methylene Blue, Rhodamine B and atrazine in a high-salinity system(0.2 mol/L Na_2SO_4) with the Mag-CuO/PMS process were 95.81%, 74.57%, 100% and 100%,respectively.Meanwhile, Mag-CuO still maintained excellent catalytic activity in other salt systems including one or more salt components(NaCl, NaNO_3, Na_2HPO_4, NaHCO_3).A radical-quenching study and electron paramagnetic resonance analysis confirmed that singlet oxygen(~1O_2) was the dominant reactive oxygen species for the oxidation of organic pollutants in high-salinity systems, which is less susceptible to hindrance by background constituents in wastewater than radicals(~·OH or SO_4~(·-)).The surface hydroxylation of the catalyst and catalytic redox cycle including Cu and Fe are responsible for the generation of~1O_2.The developed Mag-CuO catalyst shows good application prospects for the removal of organic pollutants from saline wastewater.     

长柄扁桃核壳活性炭的制备及表征

以长柄扁桃核壳为原料采用磷酸活化法制备活性炭,分别研究了温度、时间、浸渍比和磷酸浓度对活性炭吸附性能的影响;进而采用氮气吸附曲线和SEM对最佳工艺条件下的活性炭进行了表征。结果表明,长柄扁桃核壳是一种优质的活性炭原料;当温度为400℃,活化时间2 h,浸渍比2：1,磷酸浓度60%时,得到产率为46.46%,碘吸附值和亚甲基蓝吸附值分别为1 073 mg/g、255 mg/g,比表面积高达1 740 m²/g,中孔率为73.12%的孔隙发达的高中孔率活性炭。     

氧浓度对煤低温氧化热效应影响规律研究

为了准确掌握氧浓度对煤低温氧化热效应的影响,采用C80微量量热仪研究低温阶段煤氧化的自热过程,根据单升温速率的非等温动力学分析方法,得到不同氧浓度下煤样的活化能。研究结果表明:氧浓度对实验初始阶段的热流曲线和放热量的影响较小,随着温度的升高,氧浓度对热流曲线和放热量影响逐渐变得明显,放热趋势随着氧浓度的增大而增强;煤样的初始放热温度随着氧浓度的增大而降低;活化能随着氧气浓度的降低呈阶梯式上升;总放热量和氧浓度服从线性方程y=ax+b;与21%（空气气氛）氧浓度相比,15%,10%和5%氧浓度下煤的放热量分别降低了约19%,33%和46%,表明降低氧浓度对煤样的氧化放热具有明显的减缓作用。因此可以加强采空区的密闭性检测、注入惰性气体,使采空区的氧浓度尽可能地低,对采空区煤自热升温的防治有着理论指导意义。     

The role of parental behaviour for the development of behaviour specific environmental norms – The example of recycling and re-use behaviour

Based on the norm activation theory we developed assumptions about how parents may influence specific pro-environmental behaviours (i.e. re-use of paper and recycling) of their children (age 8–10). A sample of 206 parent-child-dyads were investigated using questionnaires recording norm activation model variables for children (i.e. awareness of need, awareness of consequences, personal norm, subjective norm, pro-environmental behaviour), as well as communication behaviour and actual behaviour of parents. For both behaviours (re-use and recycling) two separate structural equation models were tested (N = 206 and N = 194). Model fit statistics indicate a good fit of empirical data and model structure for both behaviours, supporting our assumption that the norm activation model can be applied to pro-environmental behaviour of young children. Communication behaviour of parents had a different influence on the two respective behaviours. While parents seemed to influence their children's recycling behaviour via sanctions and their own behaviour, re-use of paper was mainly influenced via communication of problem knowledge.     

硫铁化物氧化自燃的动力学分析

为研究含硫油品储油罐中硫铁化物的自燃倾向性,采用STA8000同步热分析仪对10,15,20℃/min等不同升温速率和15,20,25 mL/min等不同空气流量下的硫铁化物进行试验,并通过获得的TG-DSC曲线研究试样的自燃特性;在此基础上,根据Coat模型,利用不同反应机理函数对热重数据进行分析。结果表明:该试验条件下,硫铁化物的氧化进程符合三级反应动力学机制;得出了硫铁化物在不同升温速率和空气流量下的表观活化能;在560～746℃温度区间内,随着升温速率的增加,空气流量的加大,活化能数值明显减小,自燃倾向性增大。研究结果可为预防和控制因硫铁化物自燃引发的火灾、爆炸事故提供理论参考。     

UV强化草酸络合Fe3+活化过硫酸盐氧化降解苯胺

采用UV-草酸络合Fe~(3+)[UV-Fe(C_2O_4)3-3]活化过硫酸钠(PS)氧化降解苯胺,研究了Fe(C_2O_4)3-3浓度,PS浓度,pH对PS活化效率及苯胺氧化降解效果的影响机制.结果表明,Fe(C_2O_4)3-3浓度和pH决定了UV-Fe(C_2O_4)3-3体系中Fe~(3+)向Fe2+的转化过程,并对活化PS氧化降解苯胺产生显著影响.随着Fe(C_2O_4)3-3浓度增加,PS的分解率不断提高,但当浓度高于0.75 mmol·L~(-1)时,草酸根离子(C2O_2-4)对硫酸根自由基(SO·-4)的竞争以及SO·-4之间的相互淬灭作用降低了苯胺的降解效果,降解速率大小顺序为5 mmol·L~(-1)0.25 mmol·L~(-1)0.5 mmol·L~(-1)1 mmol·L~(-1)0.75 mmol·L~(-1);中性和碱性条件不利于Fe(C_2O_4)3-3发生光化学反应生成Fe2+,但当初始pH为7和9时,由于PS活化分解过程降低反应体系pH,反应300min时PS的活化率可分别达到74%和67%,苯胺去除率分别高达91%和97%,均高于初始pH为酸性条件下的结果;苯胺降解率随初始PS浓度增加而增大,当PS浓度大于10 mmol·L~(-1)时,苯胺降解过程由二级反应变为准一级反应,但此时过量的PS因与SO·-4发生反应而显著降低PS用于氧化降解苯胺的利用率.