电解液浓度及电流密度对混凝土上沉积Cu2O防护层效果的影响

使用脉冲电沉积法制备用于混凝土防护的Cu₂O沉积层,研究电解液浓度及电流密度对Cu₂O电沉积效果的影响。测定了电沉积处理后Cu₂O沉积层与试件的黏结强度、试件的渗透系数,采用XRD、SEM对Cu₂O沉积层的矿物组成及形貌进行了分析。结果表明:Cu₂O沉积层与试件的黏结强度随电解液浓度或电流密度的增大均呈现先增大后减小的规律,试件的渗透系数随电解液浓度或电流密度的增大均呈现先减小后增大的规律。电解液浓度、电流密度对沉积物矿物组成的影响较小,对沉积物形貌的影响较大。电解液浓度的增大,使Cu₂O以聚集模式生长;电流密度的增大,使Cu₂O形貌由无规则片状变为"金字塔"状。     

负载型PEG/水合盐复合相变储能材料的性能研究

随着社会的发展,能源与环境已成为了限制经济发展的重要因素。在现有的热能储存领域内,传统的无机水合盐相变材料,存在重复性差、相分离和过冷的缺点。基于此,以聚乙二醇6000(PEG6000)、七水硫酸镁(MgSO₄·7H₂O)为主体,以SiO₂为载体,通过凝胶-溶胶法制备负载型有机-无机复合相变储能材料,研究了PEG6000/MgSO₄·7H₂O的质量比以及烘焙温度对产品性能的影响。结果表明,PEG6000与MgSO₄·7H₂O对于储热性能具有一定的拮抗作用。若MgSO₄·7H₂O质量比过高导致复合材料难以形成凝胶,因加热过程中结晶水相变为水蒸气散失,从而对储热性能造成严重影响。但水合盐在一定程度上可缓解PEG相变漏液和水合盐相变过冷的问题。与纯PEG做主体相对比,复合材料相变焓普遍降低,且不同样品间的相变焓的差距较大,在13～121 J/g。研究进一步表明加入PEG6000后MgSO_...     

仿南宋官窑粉青釉配方组成的优化研究

探讨了影响仿南宋官窑青釉配方组成的主要影响因素,如SiO₂/Al₂O₃、K₂O/Na₂O摩尔比、Fe₂O₃等因素对其性能影响。试验结果表明：当SiO₂/Al₂O₃摩尔比为7.5,K₂O/Na₂O摩尔比为9,Fe₂O₃的摩尔含量在0.15mol～0.2mol时,获得了良好的粉青裂纹釉面效果。     

六水氯化钙用于新型建筑节能材料

建筑行业能源消耗持续走高,迫切需要对传统建筑材料进行改性。本文阐释相变材料储能原理,以CaCl₂·6H₂O为基体材料,SrCl₂·6H₂O与凹凸棒土分别作为成核剂与增稠剂,改善其过冷度与相分离的负面特性;与MgCl₂·6H₂O制备二元共晶复合材料,用于调节相变温度;膨胀珍珠岩作为包覆介质,吸附相变材料避免液漏,同时担当骨料,保证强度。利用DSC、XRD、步冷曲线对其热物性、物相结构、过冷度等进行表征测试,最终获得蓄热性能优异的新型建筑节能材料。     

用酶联免疫法测定虾蟹中残留的氯霉素

采用酶联免疫法测定了南美白对虾Penaeus vannam ei和中华绒螯蟹Eriocheir sinensis中残留的氯霉素。比较了用不同方法处理样品对检测结果的影响,通过对检测范围、精密度、回收率等项目的测定,验证了该方法的可靠性。结果表明:氯霉素标准液为50⁴050 ng/L时,具有良好的线性关系;板间变异系数小于16.4%,样品测定的变异系数为9.4%4050 ng/L时,具有良好的线性关系;板间变异系数小于16.4%,样品测定的变异系数为9.4%¹3.8%;用乙腈水溶液方法提取的回收率(84%13.8%;用乙腈水溶液方法提取的回收率(84%¹16%)比用乙酸乙酯提取的回收率(62%116%)比用乙酸乙酯提取的回收率(62%⁹2%)高。     

火焰原子吸收光谱法测定铜冶炼渣中镍

通过对铜冶炼渣化学组成和性质的研究,确定了测定镍的实验方法。铜冶炼渣中二氧化硅含量在20%⁴0%,硫含量10%40%,硫含量10%²0%,样品的分解具有一定的难度,必然影响镍的测定结果,因此需在样品分解过程中加入一定量的氟化氢铵、溴使二氧化硅生成四氟化硅、硫生成硫化氢挥发除去,溶液中其余共存元素主要有铜、银、铁、锌等元素不干扰测定结果,在硝酸(5%)介质中,用火焰原子吸收光谱法测定镍的含量,测定范围为0.01%20%,样品的分解具有一定的难度,必然影响镍的测定结果,因此需在样品分解过程中加入一定量的氟化氢铵、溴使二氧化硅生成四氟化硅、硫生成硫化氢挥发除去,溶液中其余共存元素主要有铜、银、铁、锌等元素不干扰测定结果,在硝酸(5%)介质中,用火焰原子吸收光谱法测定镍的含量,测定范围为0.01%¹%,加标回收率在99.5%1%,加标回收率在99.5%¹00.4%,测定结果的相对标准偏差(n=7)在0.61%100.4%,测定结果的相对标准偏差(n=7)在0.61%¹.18%,检出限为0.004μg/mL,方法快速,简捷,能够满足日常生产检测需要。     

不同碳源驯化聚糖菌反硝化及N2O释放特性

为了确定反硝化聚糖菌(DGAOs)的脱氮性能及N₂O释放特性,采用序批式生物反应器,分别以乙酸钠和葡萄糖为碳源(反应器分别记作SBRAc和SBRGl),考察其脱氮过程中的碳源变化以及N₂O释放特性。结果表明,SBRAc和SBRGl的总氮去除率分别为(80.2±2.8)%和(63.4±3.5)%,N₂O产率分别为(7.16±1.43)%和(13.35±2.46)%。以乙酸钠为碳源时,聚糖菌厌氧阶段吸收的有机物主要以胞内聚-β-羟基烷酸(PHA)形式储存;以葡萄糖为碳源时,部分有机物用于胞内糖原(Gly)的积累,PHA合成量减少。聚糖菌内源反硝化过程中,依次利用胞内PHA和Gly作为内碳源,且PHA提供电子的速率远大于Gly,导致SBRGl内NO₂^-大量积累、N₂O释放量增加。NO₂^-对氧化亚氮还原酶活性的抑制效应是导致聚糖菌内源反硝化过程释放N₂O的主要因素。与葡萄糖相比,乙酸钠更易被反硝化聚糖菌吸收为易利用的内碳源PHA,并降低反硝化过程中N₂O的释放量。     

冀东中部稀有金属花岗伟晶岩的发现及意义

冀东地区位于华北克拉通北缘东段马兰峪复式背斜,是中国北方重要的内生金属成矿区。最近,在冀东中部新发现了一系列LCT型和NYF型稀有金属花岗伟晶岩,同空间伴生绢英岩化蚀变岩和稀有金属石英脉,成矿元素包括Ag、Au、Rb、Li、Nb、Zr、HREE、Th等。LCT型花岗伟晶岩包括锂云母/白云母花岗伟晶岩和天河石花岗伟晶岩,Rb₂O含量最高可达0.43%,最低为0.06%;Li₂O分布不均,仅在锂云母花岗伟晶岩中富集,最高可达0.33%。NYF型电气石花岗伟晶岩主要富集Nb,局部富集电气石,Nb含量为0.05%～0.06%,Ta含量很低,ThO₂含量为0.02%～0.05%。同空间的绢英岩化蚀变岩Rb₂O含量为0.06%～0.15%,Li₂O含量为0.07%～0.22%,局部含金,最高品位可达1.57×10^-6;稀有金属石英脉,Nb₂O₅含量为0.06%～0.50%,富集Zr、重稀土、Th、U、Ag,其中Ag品位为18...     

甘肃狼娃山铁矿床火山岩地球化学特征及其对铁成矿的制约

狼娃山铁矿床位于中亚造山带西南缘的北山多金属成矿带中,为甘蒙北山地区主要的铁矿床之一。为探寻狼娃山铁矿床中火山岩对铁成矿的影响,本文通过系统的野外地质调查、全岩及单矿物主微量元素分析等方法,阐明了狼娃山矿床下石炭统火山岩的构造背景、成矿物质来源及火山活动对铁成矿的影响。研究结果表明,该矿床火山岩形成于晚古生代活动大陆边缘局部伸展作用环境;矿床下石炭统白山组火山岩与火山口相火山岩具有极为相似的岩相学特征,铁矿的产出受控于喷发—喷溢相岩层;火山岩具有高的SiO₂、Na₂O、K₂O、CaO/(Na₂O+K₂O)、A/CNK(0.85～1.89)值和低的P₂O₅、TiO₂含量,指示了矿体形成主要与喷发过程的岩浆分异作用有关。综合研究认为,狼娃山铁矿床的形成与下石炭统白山组中酸性火山岩具有密切成因联系,未来找矿方向应主要关注于熔结凝灰岩及部分凝灰岩岩层。     

N2O分子特殊结构形成机制的定性理论研究

直线型N₂O分子的最稳定构象为N-N-O结构,而非N-O-N结构。为了解释N-N-O这一特殊结构的合理性和稳定性,本文利用分子点群的方法,构建了直线型N₂O的σ和π分子轨道:并依据分子轨道的电子划分规则得出直线型N₂O分子中两端位置电子分布多于中间位置。由于O的电负性大于N,所以O原子会优先占据分布较多电子的两端位置,因此,N-N-0结构比N-O-N结构更为合理。     

硼化合物对WF-PVC热解和燃烧的影响

采用热重分析法和锥形量热仪测试方法研究硼化合物Na2B8O13.4H2O和2ZnO.3B2O3.3.5H2O对PVC木塑复合材料(WF-PVC)热解和燃烧过程的影响。结果表明:Na2B8O13.4H2O对WF-PVC热解过程影响较小,2ZnO.3B2O3.3.5H2O使WF-PVC热解过程的残炭量从18.04%提高到27.57%。与未经处理的WF-PVC相比,加入硼化合物均使燃烧过程的总热释放量(THR)和总烟释放量(TSP)降低,其中,2ZnO.3B2O3.3.5H2O使THR和TSP分别降低36.3%和55.8%,阻燃和抑烟效果显著。2ZnO.3B2O3.3.5H2O在WF-PVC中阻燃作用以凝聚相为主,同时伴随气相中的化学作用;Na2B8O13.4H2O在WF-PVC中为凝聚相作用机理。     

等离子光谱法测定城市污泥中总镉、总铬的方法改进

目前检测城市污泥中总镉、总铬的标准方法为<城市污水处理厂污泥检验方法>(CJ/T 221-2005),该方法样品消解时间长、酸用量大,为此改进了样品消解方法,分别采用HNO3-H2O2常压消解、HNO3-H2O2微波消解法处理污泥样品,然后采用等离子光谱法检测污泥中的总镉、总铬.与标准方法的对比试验结果表明,两种方法的相对偏差为0.8%～7.2%.改进的常压消解法的加标回收率:总镉为98.5%～105%,总铬为94.2%～95.6%;微波消解的加标回收率:总镉为104%～106%,总铬为98.5%～102%;改进方法的检出限:总镉为0.000 75 mg/L,总铬为0.002 3 mg/L.     

R_2O、SO_3对回转窑煅烧和熟料质量的影响

论述了R2 O、SO3 微组分对回转窑煅烧结皮、结圈和熟料质量的影响。分析了R2 O、SO3 对水泥熟料强度、凝结时间、安定性和水化热等的不利影响 ,提出了相关解决办法和控制措施。介绍了低碱水泥熟料的生产控制方法     

O3/H2O2联合氧化法预处理制药废水的初步探讨

针对制药废水的特点和目前制药废水预处理技术现状,介绍了O3/H2O2在制药废水处理中的应用,阐述了O3/H2O2氧化工艺机理,分析了O3/H2O2联合氧化法在工程实际中的应用情况,并通过与其他方法对比,得出该工艺是最好的制药废水预处理工艺。     

UF膜组件的有机污染及清洗

近年来,超滤（UF）膜组件的污染问题主要集中在有机物污染的范围。利用几种化学药剂对聚砜超滤膜有机污染造成的堵塞的清洗方式进行了试验研究,研究了UF件的有机污染行为及膜组件污染物的去除。实验证明NaClO,H2O2和NaOH对于UF膜的有机污染去除都有一定的效果,其中H2O2的去除效果最好。控制原水的PH值有利于减轻膜污染。同时,以NaOH／NaClO及NaOH／H2O2水溶液相结合的方式对于膜的蛋白质污染的去除也有很好的效果,能够使超滤膜的渗透水通量恢复到初始值。同时还对UF膜的有机污染形成基理进行了分析。     

Comparison between real time and flask measurements of atmospheric O2 and CO2 performed at the High Altitude Research Station Jungfraujoch, Switzerland

First real time CO2 and O2 measurements on the High Altitude Research Station Jungfraujoch (Switzerland) are compared with corresponding flasks samples. Whereas CO2 measurements show a good agreement, O2 compares only moderately. Real time O2 measurements are performed using two different methods, i.e. by paramagnetic and fuel cells. Fuel cell values exhibit significantly higher scatter, but they compare acceptably well with the paramagnetic values when averaging over 228 min (20 point running mean). Continuous measurements are powerful in many respects in contrast to spot-like flask sampling. They help to set up data selection criteria and to improve the robustness of trend calculations. Further, real time measurements help to partition the anthropogenic CO2 increase into ocean and terrestrial biosphere for short-time variations of minutes, hours, days, which are not covered by flask sampling.     

含溴矿泉水臭氧化过程中溴酸盐的生成及控制

在阐述含溴矿泉水臭氧化过程中溴酸盐生成机理及检测方法的基础上,总结了Br-浓度、臭氧投加量、臭氧投加方式、温度、反应时间等因素对溴酸盐生成的影响,分别从降低pH、加氨、加过氧化氢、改善反应器、投加活性炭、优化臭氧投加方式等方面探讨了控制溴酸盐生成的可能措施.     

Mineralization of salicylic acid in acidic aqueous medium by electrochemical advanced oxidation processes using platinum and boron-doped diamond as anode and cathodically generated hydrogen peroxide

Solutions containing 164 mg L(-1) salicylic acid of pH 3.0 have been degraded by electrochemical advanced oxidation processes such as anodic oxidation, anodic oxidation with electrogenerated H(2)O(2), electro-Fenton, photoelectro-Fenton and solar photoelectro-Fenton at constant current density. Their oxidation power has been comparatively studied in a one-compartment cell with a Pt or boron-doped diamond (BDD) anode and a graphite or O(2)-diffusion cathode. In the three latter procedures, 0.5mM Fe(2+) is added to the solution to form hydroxyl radical (()OH) from Fenton's reaction between Fe(2+) and H(2)O(2) generated at the O(2)-diffusion cathode. Total mineralization is attained for all methods with BDD and for photoelectro-Fenton and solar photoelectro-Fenton with Pt. The poor decontamination achieved in anodic oxidation and electro-Fenton with Pt is explained by the slow removal of most pollutants by ()OH formed from water oxidation at the Pt anode in comparison to their quick destruction with ()OH produced at BDD. ()OH generated from Fenton's reaction oxidizes rapidly all aromatic pollutants, but it cannot destroy final Fe(III)-oxalate complexes. Solar photoelectro-Fenton treatments always yield quicker degradation rate due to the very fast photodecarboxylation of these complexes by UVA irradiation supplied by solar light. The effect of current density on the degradation rate, efficiency and energy cost of all methods is examined. The salicylic acid decay always follows a pseudo-first-order kinetics. 2,3-Dihydroxybenzoic, 2,5-dihydroxybenzoic, 2,6-dihydroxybenzoic, alpha-ketoglutaric, glycolic, glyoxylic, maleic, fumaric, malic, tartronic and oxalic acids are detected as oxidation products. A general reaction sequence for salicylic acid mineralization considering all these intermediates is proposed.     

Removal of the surfactant sodium dodecylbenzenesulphonate from water by simultaneous use of ozone and powdered activated carbon: comparison with systems based on O3 and O3/H2O2

A study was conducted on the efficacy of the system based on the simultaneous use of ozone and powdered activated carbon (PAC) in removing sodium dodecylbenzenesulphonate (SDBS) from drinking waters and on the influence of operational parameters (PAC dose, ozone dose and presence of radical scavengers [HCO3-]) on this process. Results obtained showed that low doses of PAC during SDBS ozonation markedly increased the rate of SDBS removal from the medium. These results are due to the combined effect of two processes: (i) SDBS adsorption on the activated carbon surface and (ii) transformation of the dissolved ozone into .OH radicals. At higher ozone and PAC doses, there was a higher rate of SDBS removal from the medium. The presence of HCO3- in the medium reduced the SDBS removal rate of the O3/PAC system. This finding confirms that the presence of PAC during SDBS ozonation favours ozone transformation into .OH radicals. Comparison of the O3/PAC system with systems based on the use of O3 or O3/H2O2 showed that the efficacy of the O3/PAC system to remove SDBS is much greater than that of the traditional oxidation methods. Thus, in the first 5 min of treatment (usual hydraulic retention time), the percentage of SDBS removed was 18% and 30% for the O3 and O3/H2O2 systems, respectively, compared with 70% for the O3/PAC system. SDBS ozonation in surface waters intended for human consumption demonstrated that the O3/PAC approach is the most efficacious of the studied systems, considerably increasing the SDBS removal rate and also reducing the concentration of dissolved organic carbon. Therefore, the results of this study show that the system based on O3/PAC is a highly attractive option for the treatment of drinking water.     

A^2O工艺的优化

通过分析A^2O工艺存在的问题,提出多点进水倒置A^2O工艺,并对该工艺进行了试验,其试验结果表明,NH3-N只能达到二级排放标准,通过对各方面原因的分析,提出了解决问题的办法。