仿古铸铁的局部腐蚀和相转移研究

The corrosion behaviors of simulated archaeological iron in solution （0.06 mol·L^-1 NaCl＋0.03 mol·L^-1 Na2SO4＋0.01 mol·L^-1 NaHCO3） simulating soil water composition was investigated by potentialdynamic polarization, constant potential polarization, and simulated occluded cell （O.C.） galvanostatic tests. X-ray diffraction （XRD）, energy dispersive spectrometry （EDS）, and scanning electron microscope （SEM） were used to study the corrosion morphology and the evolution of corrosion product. The objective was to discover the transformation process of archaeological iron, and determine the distribution of chlorinated corrosion products. The results showed that the presence of crevice, cavities, and channels facilitates the localized corrosion under rusts; the autocatalytic effect increases the concentration of Fe^2＋, Cl^-, and SO4^2- , and promotes local acidification within the crevices and cavities. Meanwhile, the phase transformation of corrosion products is concluded to proceed by means of two ways. One is that the ferrous ions are transformed into different kinds of FeOOH via the intermediate Fe（Ⅱ）-Fe（Ⅲ） hydroxyl-salt （i.e. Green Rusts）; the other is that the Fe^2＋ ions are transformed into FeCl2, FeCl3, and orange powders akaganeite at the crevices and cavities.     

潮湿大气中NO-3和HSO-3对模拟铸铁文物的腐蚀研究

NO3^- and HSO3^- induced corrosion of simulated archaeological iron in humid-acid atmosphere was studied by using periodic wet-dry tests. Surface tension tests, electrochemical impedance measurement, stereoscopic microscopy and energy dispersive atomic X-ray analysis （EDAX） were used to investigate the corrosion processes and products. The results of mass loss measurement showed that the corrosion kinetics can be approximately described by △W = At^B. With the addition of NO3^-, the value of B increases. NO3^- acts as an inhibitor in the HSO3^- bearing pollutant during the corrosion process. Both the electrochemical impedance measurement and surface tension test confirmed the result of mass loss measurement. In addition, we found that the attack of anions to the metal at the initial corrosion stage was in good agreement with their surface activity.     

6.0mol•L－1KOH溶液中锌单晶（002）和（100）晶面的电化学行为

In this article, the electrochemical performance of the electrodes of zinc polycrystal, Zn（002） and Zn（100） single crystals were studied by the Tafel line extrapolation of the potentio-dynamic polarization curves, the cyclic voltammetry and the charge/discharge experiment. The results shows that in 6.0 mol·L^-1 KOH solution the corrosion rate of Zn polycrystal, Zn（100） and Zn（002） single crystals decreases in turn; and the reversibility and the charge/discharge performance of Zn single crystal was superior to Zn polycrystal. The dendrite growth of the surface of Zn polycrvstal was easier than Zn single crystal during the stages of charge/discharge.     

使用纤维素-钛白粉复合扩张床阴离子吸附剂提取D-2-氯丙酸脱卤酶

The TiO2-densified cellulose composite beads were activated by epichlorohydrin and coupled with diethylamine, to function as an anion exchanger for expanded bed chromatography. The adsorbent exhibited a favorable performance of expanded bed adsorption for proteins, and therefore was applied to the expanded bed recovery of D-2-chloropropionic acid dehalogenase directly from the unclarified homogenate of Pseudomonas sp. NT21. The binding capacity of the dehalogenase was found to be 8.54U·ml^-1 adsorbent, and two active peaks were eluted respectively at 0.15mol·L^-1 and 0.3mol·L^-1 （NH4）2SO4. The result indicated that the overall enzyme yield was 68%, with a purification factor of 22. In comparison to other recovery processes, the yield of the expanded bed process rises at least 70%, simultaneously saving a great deal of operation time and costs.     

Removal of Cd（II） by Nanometer AIO（OH） Loaded on Fiberglass with Activated Carbon Fiber Felt as Carrier

A new nanometer material, nanometer AlO（OH） loaded on the fiberglass with activated carbon fibers felt（ACF） as the carrier, was prepared by hydrolytic reaction for the removal of Cd（II） from aqueous solution using column adsorption experiment. As was confirmed by XRD determination, the hydrolysis production loaded on fiberglass was similar to the orthorhombic phase AlO（OH）. SEM images showed that AlO（OH） particles were in the form of small aggregated clusters. The Thomas model was applied for estimating the kinetic parameters and the saturated adsorption ability of Cd（II） adsorption on the new adsorbent. The results showed that the maximum adsorption capacity of Cd（II） was 128.50 mg·g^-1 and 117.86 mg·g^-1 for the adsorbent mass of 0.3289 g and the adsorbent mass of 0.2867 g, respectively. The elution experiment result indicated that the adsorbed Cd ions was easily desorbed from the material with 0.1 mol·L^-1 HCl solution. Adsorption-desorption cycles showed the feasibility of repealed uses of the composited material. The adsorption capacities were influenced by pH and the initial Cd（II） concentration. The amount adsorbed was greatest at pH 6.5 and the initial Cd（II） concentration of 0.07 mg·L^-1, respectively. Nanometer AlO（OH） played a major role in the adsorption process, whereas the fiberglass and ACF were assistants in the process of removing Cd（II）. In addition, the adsorption capacities for Cd（II） were obviously reduced from 128.50 mg·L^-1 to 64.28 mg·L^-1 when Pb ions were present because Pb ions took up more adsorption sites.     

氯离子在含硫氮污染物的环境中对模拟铁器文物的大气腐蚀的影响

The effect of chloride on the atmospheric corrosion of cast iron in sulphur or nitrogen-bearing pollutant was investigated by using periodic wet-dry test, electrochemical experiment and surface tension test. Scanning electron microscopy coupled with energy dispersive atomic （EDAX） and stereoscopic microscopy was used to identify the corrosion processes and products. Cl^- and NO3^- were shown accelerating effects during the whole corrosion process but depression effects were observed in Cl^- and HSO3^- bearing pollutant at the initial corrosion stage. However, with the corrosion going on, the depression effects was less obviously and the initial corrosion process was investigated from the viewpoint of surface activity. At the initial corrosion stage, the corrosion rate was proportional to the adsorptivity of anions, but as corrosion went on, the penetration effect of anions and different characteristics of the corrosion products began to dominate the corrosion process, which led to changes on the corrosion rate.     

NO_3~-and HSO_3~-Induced Corrosion of Simulated Archaeological Iron in Humid-Acid Atmosphere

NO_3~-and HSO_3~-induced corrosion of simulated archaeological iron in humid-acid atmosphere was studied by using periodic wet-dry tests.Surface tension tests,electrochemical impedance measurement,stereoscopic microscopy and energy dispersive atomic X-ray analysis(EDAX)were used to investigate the corrosion processes and products.The results of mass loss measurement showed that the corrosion kinetics can be approximately described by △W=At~B.With the addition of NO_3~-,the value of B increases.NO_3~-acts as an inhibitor in the HSO_3~-bearing pollutant during the corrosion process.Both the electrochemical impedance measurement and surface tension test confirmed the result of mass loss measurement.In addition,we found that the attack of anions to the metal at the initial corrosion stage was in good agreement with their surface activity.     

PVC membrane selective electrode for determination of cadmium(II) ion in chocolate samples

Benzil bis（carbohydrazone） （BBC） is prepared and explored as new NN Schiff’s base, which plays the role of an excellent ion carrier in the construction of a Cd（II） ion membrane sensor. The tris（2-ethylhexyl） phosphate best performance corresponds to a membrane composition of 30%poly （vinyl chloride）, 65%（TEHP）, 3.5%BBC and 1.5%tetradodecyl-ammoniumtetrakis（4-chlorophenyl） borate （ETH 500）. This sensor shows very good selectivity and sensitivity towards cadmium ion over a wide variety of cations, including alkali, alkaline earth, transition and heavy metal ions. The effect of membrane composition, selectivity, pH and influence of additive on the response properties of electrode were investigated. The response mechanism was discussed in the view of UV-spectroscopy. The electrode exhibits a Nernstian behavior （with slope of 29.7 mV per decade） over a very wide concentration range from 1.0×10^-1 to 1.0×10^-8 mol·L^-1 with a detection limit of 3.2×10^-8 mol·L^-1. It shows rela-tively fast response time in whole concentration range （〈8 s） and can be used for at least 10 weeks in the pH range of 2.0-9.0. The proposed sensor is successfully used for the determination of cadmium in different chocolate sam-ples and as indicator electrode in titration with ethylene diamine tetraacetate （EDTA）.     

复合生物反应器亚硝酸型同步硝化反硝化脱氮

Sequence hybrid biological reactor （SHBR） was proposed, and some key control parameters were investigated for nitrogen removal from wastewater by simultaneous nitrification and denitrification （SND） via nitrite. SND via nitrite was achieved in SHBR by controlling demand oxygen （DO） concentration. There was a programmed decrease of the DO from 2.50 mg·L^-1 to 0.30 mg·L^-1, and the average nitrite accumulation rate （NAR） was increased from 16.5% to 95.5% in 3 weeks. Subsequently, further increase in DO concentration to 1.50 mg·L^-1 did not destroy the partial nitrification to nitrite. The results showed that limited air flow rate to cause oxygen deficiency in the reactor would eventually induce only nitrification to nitrite and not further to nitrate. Nitrogen removal efficiency was increased with the increase in NAR, that is, NAR was increased from 60% to 90%, and total nitrogen removal efficiency was increased from 68% to 85%. The SHBR could tolerate high organic loading rate （OLR）, COD and ammonia-nitrogen removal efficiency were greater than 92% and 93.5%, respectively,, and it even operated under low DO concentration （0.5 mg·L^-1） and maintained high OLR （4.0 kg COD·m^-3·d^-1）. The presence of biofilm positively affected the activated sludge settling capability, and sludge volume index （SVI） of activated sludge in SHBR never hit more than 90 ml·L^-1 throughout the experiments.     

柴油微乳酸体系的制备及其性能研究

The microemulsified acid system composed by diesel oil, hydrochloric acid and emulsifier was investi- gated in this paper. The stability of microemulsified acid and the phase behavior of the microemulsified system Were studied. The size distribution and the corrosion inhibition performance were also observed. The results showed that the diesel oil microemulsified acid system possessed small size and good stability under different temperature.The tolerance to CaCl2 reached 80 g·L^-1. Compared with the same concentration hydrochloric acid solution, the corrosion inhibition performance of the diesel oil microemulsified acid system was remarkable.     

盐类浓度对油酸咪唑啉季铵盐缓蚀率的影响

针对油田污水富含钙、镁、钠等盐类的现状,合成了油酸咪唑啉季铵盐,采用电化学极化法和静态失重法测试了其缓蚀性能,并采用电化学极化法考察了强酸腐蚀介质中氯化钙、氯化镁及氯化钠3种盐的浓度对该缓蚀剂缓蚀率的影响。结果表明:该缓蚀剂是一种以阳极抑制为主的混合型缓蚀剂;在1mol·L-1 HCl溶液中,当缓蚀剂浓度为5mg·L-1时,N80钢片的腐蚀速率和缓蚀剂的缓蚀率趋于稳定;随着介质中盐类浓度的增大,缓蚀剂的缓蚀率逐渐减小。分析认为,缓蚀率减小的原因可能是由于介质的电导率增大,导致腐蚀速率加快。     

X70管线钢在CO2-3/HCO-3体系中表面膜性能研究

The electrochemical behavior of X70 pipeline steel in (0.5 mol· L-1 Na2CO3+1 mol· L-1 NaHCO3)solution was studied by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) were used to analyze the composition and microstructure of the surface film. The results showed that there were two anodic peaks at -600 mV and -350 mV.The surface film formed at -600 mV mainly consisted of ferrous carbonates and ferrous hydroxycarbonates. It had a small reaction resistance. It was metastable and possessed poor protective property. Numerous pits and microcracks existed on the film, which could be the active paths for the initiation of stress corrosion cracking. The surface film formed at -350 mV, mainly consisted of ferric oxides. It has high reaction resistance and offered good protection for the substrate.     

四元水盐体系KCl-NaCl-CaCl2-H2O蒸气压测定

钢铁企业富钾烧结电除尘灰水浸液经脱除重金属杂质后可看作四元水盐体系KCl-NaCl-CaCl2-H2O,从该体系分离出氯化钾,需要首先通过蒸发浓缩及蒸发结晶。为了合理有效的控制蒸发操作过程,今采用静态法实验测定了四元水盐体系KCl-NaCl-CaCl2-H2O在KCl浓度为0～3 mol L 1,NaCl浓度为0～2 mol L 1,CaCl2浓度为0～1 mol L 1,温度为303.15～373.15 K的蒸气压,并通过数学线性回归得出了该体系的蒸气压与温度和体系组成的关系式,该关系式的获得有望为实际蒸发操作过程控制提供理论依据。     

A study on simultaneous removal of NO and SO2 by using sodium persulfate aqueous scrubbing

Nitric oxide(NO) removal and sulfur dioxide(SO_2) removal by sodium persulfate(Na_2S_2O_8) were studied in a Bubble Column Reactor. The proposed reaction pathways of NO and SO_2 removal are discussed. The effects of temperatures(35–90 °C), Na_2S_2O_8(0.05–0.5 mol·L~(-1)), Fe SO4(0.5–5.0 m mol·L~(-1)) and H_2O_2(0.25 mol·L~(-1))on NO and SO_2 removal were investigated. The results indicated that increased persulfate concentration led to increase in NO removal at various temperatures. SO_2 was almost completely removed in the temperature range of 55–85 °C. Fe~(2+)accelerated persulfate activation and enhanced NO removal efficiency. At 0.2 mol·L~(-1) Na_2S_2O_8 and 0.5–1.0 mmol·L~(-1) Fe~(2+), NO removal of 93.5%–99% was obtained at 75–90 °C, SO_2 removal was higher than 99% at all temperatures. The addition of 0.25 mol·L~(-1) H_2O_2 into 0.2 mol·L~(-1) Na_2S_2O_8 solution promoted NO removal efficiency apparently until utterly decomposition of H2 O2, the SO_2 removal was as high as98.4% separately at 35 °C and 80 °C.     

4-甲基咪唑在不锈钢腐蚀液中缓蚀作用的研究

本文介绍了奥氏不锈钢在Cl-浓度为1.5mol.L-1的缓蚀液中的电化学行为,分析不锈钢在不同温度和不同浓度中缓蚀液的腐蚀电位、腐蚀电流的变化规律,探索缓蚀液对不锈钢腐蚀速率的影响。结果表明:4-甲基咪唑缓蚀液对不锈钢的缓蚀效率在研究范围内随着温度和缓蚀液浓度的增加而增大,4-甲基咪唑是一种较好的高温吸附型缓蚀剂。     

毛细管电泳法测定动物肝脏中的谷胱甘肽

建立了以0.07 mol·L-1Na2HPO4-0.07 mol·L-1 KH2PO4的混合体系(pH7.38)为运行缓冲液,在230 nm紫外检测波长下,用毛细管电泳法测定鸡和猪肝脏中谷胱甘肽(GSH)的含量.结果表明:在最佳电泳条件下, GSH在5.0×10-6~1.0×10-3mol·L-1的范围内有良好的线性关系,r=0.9997,最低检出限为1.6×10-6 mol·L-1;加标回收率在94.81%~99.02%之间,RSD在1.56%~3.25%之间;该方法操作简便,快速,可靠性高,可用于动物肝脏中的谷胱甘肽含量的测定.     

多胺改性壳聚糖在盐酸介质中的缓蚀作用研究

制备了一种由四乙烯五胺(TEPA)多胺改性壳聚糖衍生物(TEPA-Ch),采用动电位极化曲线法研究了TEPA-Ch在1molL-1HCl介质中对碳钢的缓蚀作用。结果表明,TEPA-Ch为混合型缓蚀剂,在酸性介质中自发地吸附在碳钢表面,其吸附方式遵循Langmuir吸附等温式。     

草酸络合除石英砂中铁的研究

本试验通过草酸络合的方法研究了用草酸降低石英砂中铁含量的最佳试验条件。试验研究了草酸浓度、浸泡温度、浸泡时间、添加还原剂及洗涤次数对除铁效率的影响;试验结果表明:当草酸浓度0.25 mol.L-1、浸泡温度80℃、浸泡时间3 h、溶液pH值为9时有较好的除铁效果。洗涤次数和外加还原剂对本试验结果也有影响。在最优实验条件下,石英砂中的铁含量从132.0μg.g-1降低到8.5μg.g-1,除铁效率达到93.6%。     

环丙沙星、诺氟沙星、氧氟沙星在1 mol·L~(-1) HCl中对碳钢的缓蚀性能及机理研究(英文)

The inhibiting effect of ciprofloxacin,norfloxacin and ofloxacin on the corrosion of mild steel in 1 mol·L-1 HCl and the mechanism were studied at different temperatures using mass loss measurement,electrochemical method,and X-ray photoelectron spectroscopy(XPS) .Effective inhibition was shown by mass loss,potentiodynamic polarization and impedance spectroscopy measurement.The corrosion rate of the metal in the mass loss measurement,and the corrosion reaction on cathode and anode in the electrochemical measurement were accelerated when temperature was increased.XPS results showed that the inhibitors adsorbed effectively on the metal surface.