基于钴(Ⅱ)-酪氨酸络合作用的酪氨酸极谱法分析研究

在0.02mol/L硼酸盐缓冲溶液(pH8.7)中,钴(Ⅱ)与酪氨酸生成的络合物在-0.82V(vs.SCE)有一阴极极谱还原峰。基于该极谱行为建立了酪氨酸的分析体系并进行实验条件优化,其浓度在8.0×10-5至4.0×10-4mol/L之间与极谱峰电流呈良好线性关系,检出限为2.8×10-6mol/L。     

微机极谱法测定啤酒中微量铁

铁的极谱催化波已有许多报导．但铁的催化波的峰电位较负,大都在-1．5V以上。根据文献报导,铁与4-(2-吡啶偶氮)问苯二酚(商品名:PAR)的络合物催化波电位较低,而且它的最大的优点是与锰的催化波完全分离从而排除锰的重叠波干扰。我们应用此催化波测定了啤酒中微量铁,具有灵敏、重现、峰半宽小等优点,检测下限5／ug／L,线性范围10-250ug／L,相对标准偏差为4．8％．结果令人满意。目前,尚未见类似的报导。     

电镀液中Cr(Ⅵ)含量的方波伏安法测定

为了建立镀铬液Cr(Ⅵ)含量的快速测定方法,研究了Cr(Ⅵ)的电化学行为.在0.1 mol/L的氨水缓冲溶液(pH=10.0)中,Cr(Ⅵ)于-1.45 V(vs SCE)出现一灵敏的方波伏安峰,峰电流ip的高低与Cr(Ⅵ)的浓度在(0.1～2.0)×103mg/L范围内呈现良好的线性关系,由此建立了快速测定环境中Cr(Ⅵ)含量的方波伏安法.结果表明,此方法具有较高的分析测试准确性和灵敏度,方法的回归方程为ip(μA)=0.287 0 0.642 4C(mg/L),相关系数为0.988 6,检出限为0.05 mg/L Cr(Ⅵ),标准偏差为2.8%.该方法应用于实际样品电镀铬液及其废液中Cr(Ⅵ)含量的测定,结果满意.     

感光化学试剂中痕量铅极谱吸附波测定

本文研究了感光化学试剂中痕量铅的极谱催化波测定方法。在0.2M NH_4AC 0.5％三乙醇胺介质中,铅与铜铁试剂络合,出现清晰的极谱催化波。铅含量在10~(-6)～10~(-8)克/毫升范围与催化波峰电流有良好的线性关系。操作简单快速、选择性好、波形稳定。     

乙二胺-亚硝酸钠络合催化波测定天然水样中的Cr（Ⅵ）

在NH4Cl-NH4OH缓冲溶液中,Cr（Ⅵ）-乙二胺-亚硝酸钠络合体系在单扫描示波极谱仪上产生灵敏的催化波,峰电位为-1780mV,Cr（Ⅵ）的浓度为0．03—30．1μg/L范围内与峰电流有良好的线性关系,检测限为0．01μg/L。该方法已成功地应用于天然水样中Cr（Ⅵ）的测定。     

金橙G为电化学探针测定DNA的研究

在pH5.0的Britton-Robinson(B-R)缓冲溶液中,用电化学方法研究了金橙G(OG)与脱氧核糖核酸(DNA)的结合反应。OG在-0.62V处有一个灵敏的示差脉冲伏安还原峰;当在溶液中加入DNA后,随着DNA浓度的增大,OG的峰电流减小而峰电位不发生变化。峰电流的减小主要是由于溶液中DNA与OG相互结合生成了生物超分子复合物。在最佳条件下,峰电流的降低与DNA的浓度在1.0-15.0mg/L范围内呈良好的线性关系,检出限为0.35mg/L。该方法用于合成样品中DNA的测定,具有较好的回收率和选择性。     

酶催化诱导制备多孔石墨烯的研究

采用Hummers法,以石墨为原料制备氧化石墨烯(GO)。再以辣根过氧化物酶(HRP)和过氧化氢(H_2O_2)的酶催化反应,诱导制备了多孔石墨烯(PGR)。采用傅里叶红外光谱、扫描电子显微镜和电化学分析法对其结构、形貌和性能表征。结果表明:10mg/mL GO溶液加入80μL 5mg/mL HRP后,再每日加入20μL(1×10~(-3))mol/L H_2O_2反应10d可以获得最佳的多孔结构。基于此构置的生物催化诱导型葡萄糖传感器,反应25min时,可在电位为0.98V处呈现Au氧化峰,使其可用于葡萄糖的高灵敏检测。     

TAR—Ni的配合物吸附极谱催化波的研究

本文研究了在0.030M NaOH—0.040M Na_3C_6H_5O_7—0.6％NaAc介质中、TAR试剂[4—(2—噻唑偶氮)间苯二酚]与Ni生成的配合物的极谱催化波。此催化波具有很高的灵敏度。峰电位在—0.78V(相对大面积银丝醮录电极)检测限为0.1ppb镍浓度与峰电流关系在0.5ppb—200ppb范围内呈良好的线性关系。本文进行了水样中镍的含量的测定。方法简便、快速、结果较为满意。     

金属—PAN—S配合物的极谱研究——Ⅱ:Fe~(3+)—PAN—S—TEA—NH_3·H_2O—NH_4Cl体系配合吸附波

在NH_3·H_2O—NH_4Cl—三乙醇胺底液中Fe(Ⅲ)与PAN—S产生一灵敏的配合吸附波,峰电位在—0.50伏(vs.SCE)。峰电位与铁离子浓度在2.8×10~8～3.4×10~(-6)mol/L范围内线性良好,检出下限可达2.8×10~(-8)mol/L。该法用于乳粉、头发、血清等样品的测定,结果满意。     

香豆素添加剂对低温碱性化学镀镍-磷的影响

为了进一步将低温碱性化学镀镍-磷应用于工业生产,在已开发的低温碱性化学镀镍工艺基础上,重点研究了香豆素添加剂对镀速和镀层的影响。结果表明:少量香豆素能使镀速增大,但浓度大于10 mg/L后镀速反会降低;香豆素为10 mg/L时镀层平滑、致密,由球形颗粒组成,大小均匀,约为5～6μm,晶粒间无孔隙;香豆素对镍-磷镀层的组成基本无影响;香豆素为10 mg/L时镀层的XRD谱由Ni主衍射峰及Ni5P4次衍射峰组成;香豆素对Ni沉积峰电位无显著影响,但会使其阴极峰电流密度增大,且随香豆素浓度的增加先增大后减小;香豆素与磺酸类添加剂的协同作用使阴极峰电位显著负移,过电位增大。     

Electrochemically reduced graphene modified carbon ionic liquid electrode for the sensitive sensing of rutin

In this paper a graphene (GR) modified carbon ionic liquid electrode that was obtained by one-step potentiostatic electroreduction of a graphene oxide solution was described. The resulting electrode displayed excellent electrochemical performance due to the formation of highly conductive GR film on the electrode surface. Electrochemistry of rutin was carefully studied with a pair of well-defined redox peaks appeared in pH 2.5 buffer solution. Rutin exhibited a diffusion-controlled two-electron and two-proton transfer reaction on the modified electrode with the electrochemical parameters calculated. The reduction peak currents are linearly related to rutin concentration in the concentration range from 0.070 to 100.0 μmol/L with a detection limit as low as 24.0 nmol/L (3σ). The modified electrode displayed excellent selectivity with good stability, and was applied to the determination of rutin content in tablet, human serum and urine samples with satisfactory results.     

Single-walled carbon nanotubes modified carbon ionic liquid electrode for sensitive electrochemical detection of rutin

The single-walled carbon nanotubes (SWCNTs) modified carbon ionic liquid electrode (CILE) was designed and further used for the voltammetric detection of rutin in this paper. CILE was prepared by mixing graphite powder with ionic liquid (IL) 1-butyl-3-methylimidazolium tetrafluoroborate and liquid paraffin together. Based on the interaction of SWCNTs with IL present on the electrode surface, a stable SWCNTs film was formed on the CILE to get a modified electrode denoted as SWCNTs/CILE. The characteristics of SWCNTs/CILE were recorded by different methods including cyclic voltammetry, electrochemical impedance spectroscopy and scanning electron microscopy. The electrochemical behaviors of rutin on the SWCNTs/CILE were investigated by cyclic voltammetry and differential pulse voltammetry. Due to the specific interface provided by the SWCNTs-IL film, the electrochemical response of rutin was greatly enhanced with a pair of well-defined redox peaks appeared in pH 2.5 phosphate buffer solution. The oxidation peak currents showed good linear relationship with the rutin concentration in the range from 1.0 × 10^− 7 to 8.0 × 10^− 4 mol/L with the detection limit as 7.0 × 10^− 8 mol/L (3σ). The SWCNTs/CILE showed the advantages such as excellent selectivity, improved performance, good stability and it was further applied to the rutin tablets sample detection with satisfactory results.     

食品包装用功能性添加剂灯心草黄酮含量测定的研究

研究了紫外光分光光度法测定食品包装用功能性添加剂--灯心草黄酮苷含量的方法,以芦丁为参照品,测量波长为359 nm,平均回收率为100.01%,精密度为1.72%,说明紫外分光光度法是一种较理想的测定方法.     

Influence of urea, isopropanol, and propylene glycol on rutin in vitro release from cosmetic semisolid systems estimated by factorial design

Rutin, one of the major flavonoids found in an assortment of plants, was reported to act as a sun protection factor booster with high anti-UVA defense, antioxidant, antiaging, and anticellulite, by improvement of the cutaneous microcirculation. This research work aimed at evaluating the rutin in vitro release from semisolid systems, in vertical diffusion cells, containing urea, isopropanol and propylene glycol, associated or not, according to the factorial design with two levels with center point. Urea (alone and in association with isopropanol and propylene glycol) and isopropanol (alone and in association with propylene glycol) influenced significant and negatively rutin liberation in diverse parameters: flux (microg/cm(2).h); apparent permeability coefficient (cm/h); rutin amount released (microg/cm(2)); and liberation enhancement factor. In accordance with the results, the presence of propylene glycol 5.0% (wt/wt) presented statistically favorable to promote rutin release from this semisolid system with flux = 105.12 +/- 8.59 microg/cm(2).h; apparent permeability coefficient = 7.01 +/- 0.572 cm/h; rutin amount released = 648.80 +/- 53.01 microg/cm(2); and liberation enhancement factor = 1.21 +/- 0.07.     

Influence of Urea,Isopropanol, and Propylene Glycol on Rutin In Vitro Release from Cosmetic Semisolid Systems Estimated by Factorial Design

Rutin, one of the major flavonoids found in an assortment of plants, was reported to act as a sun protection factor booster with high anti-UVA defense, antioxidant, antiaging, and anticellulite, by improvement of the cutaneous microcirculation. This research work aimed at evaluating the rutin in vitro release from semisolid systems, in vertical diffusion cells, containing urea, isopropanol and propylene glycol, associated or not, according to the factorial design with two levels with center point. Urea (alone and in association with isopropanol and propylene glycol) and isopropanol (alone and in association with propylene glycol) influenced significant and negatively rutin liberation in diverse parameters: flux (μg/cm².h); apparent permeability coefficient (cm/h); rutin amount released (μg/cm²); and liberation enhancement factor. In accordance with the results, the presence of propylene glycol 5.0% (wt/wt) presented statistically favorable to promote rutin release from this semisolid system with flux?=?105.12?±?8.59 μg/cm².h; apparent permeability coefficient?=?7.01?±?0.572 cm/h; rutin amount released?=?648.80?±?53.01 μg/cm²; and liberation enhancement factor?=?1.21?±?0.07.     

水溶性环烷基咪唑啉甜菜碱的合成及其对碳钢的缓蚀性能

目前,对水溶性环烷基咪唑啉甜菜碱的合成和应用研究不够,用环烷酸、三乙烯四胺、氯乙酸钠等原料合成后作碳钢缓蚀剂,用静态挂片失重法和电化学方法,研究了其在HCl,HCl-H2S水相体系中的缓蚀性能。结果表明：水溶性环烷基咪唑啉甜菜碱在1000mg／LHCl腐蚀体系中为以抑制阳极过程为主的阴阳极混合型缓蚀剂,在HCl,HCl...     

新型射流曝气外置式MBR处理乳品废水

利用外置MBR用间歇射流曝气代替鼓风曝气;射流器安装在循环加压泵吸水管上.结果表明,经优化的射流器安装方式与普通安装方式相比能耗更低,充氧效率更高.进水CODcr 平均为l 987 mg/L,NH3-N、TN(总氮)平均为100 mg/L和114 mg/L时,TP(总磷)平均为16.33 mg/L;出水CODcr,平均为24mg./L,去除率为98.67％;出水NH3- N、TN平均为15.8mg/L和20 mg/L,去除率分别为84.33％和82％;出水TP平均为2.72 mg/L,去除率83.37％.     

Electrolytic treatment of Standard Malaysian Rubber process wastewater

A new method of Standard Malaysian Rubber (SMR) process wastewater treatment was developed based on in situ hypochlorous acid generation. The hypochlorous acid was generated in an undivided electrolytic cell consisting of two sets of graphite as anode and stainless sheets as cathode. The generated hypochlorous acid served as an oxidizing agent to destroy the organic matter present in the SMR wastewater. For an influent COD concentration of 2960 mg/L at an initial pH 4.5+/-0.1, current density 74.5 mA/cm(2), sodium chloride content 3% and electrolysis period of 75 min, resulted in the following residual values pH 7.5, COD 87 mg/L, BOD(5) 60 mg/L, TOC 65 mg/L, total chlorine 146 mg/L, turbidity 7 NTU and temperature 48 degrees C, respectively. In the case of 2% sodium chloride as an electrolyte for the above said operating condition resulted in the following values namely: pH 7.2, COD 165 mg/L, BOD(5) 105 mg/L, TOC 120 mg/L, total chlorine 120 mg/L, turbidity 27 NTU and temperature 53 degrees C, respectively. The energy requirement were found to be 30 and 46 Wh/L, while treating 24 L of SMR wastewater at 2 and 3% sodium chloride concentration at a current density 74.5 mA/cm(2). The observed energy difference was due to the improved conductivity at high sodium chloride content.     

Application of biosurfactants, rhamnolipid, and surfactin, for enhanced biodegradation of diesel-contaminated water and soil

This study investigated potential application of two biosurfactants, surfactin (SF) and rhamnolipid (RL), for enhanced biodegradation of diesel-contaminated water and soil with a series of bench-scale experiments. The rhamnolipid used in this study, a commonly isolated glycolipid biosurfactant, was produced by Pseudomonas aeruginosa J4, while the surfactin, a lipoprotein type biosurfactant, was produced by Bacillus subtilis ATCC 21332. Both biosurfactants were able to reduce surface tension to less than 30 dynes/cm from 72 dynes/cm with critical micelle concentration (CMC) values of 45 and 50 mg/L for surfactin and rhamnolipid, respectively. In addition, the results of diesel dissolution experiments also demonstrated their ability in increasing diesel solubility with increased biosurfactant addition. In diesel/water batch experiments, an addition of 40 mg/L of surfactin significantly enhanced biomass growth (2500 mg VSS/L) as well as increased diesel biodegradation percentage (94%), compared to batch experiments with no surfactin addition (1000 mg VSS/L and 40% biodegradation percentage). Addition of surfactin more than 40 mg/L, however, decreased both biomass growth and diesel biodegradation efficiency, with a worse diesel biodegradation percentage (0%) at 400 mg/L of SF addition. Similar trends were also observed for both specific rate constants of biomass growth and diesel degradation, as surfactin addition increased from 0 to 400 mg/L. Addition of rhamnolipid to diesel/water systems from 0 to 80 mg/L substantially increased biomass growth and diesel biodegradation percentage from 1000 to 2500 mg VSS/L and 40 to 100%, respectively. Rhamnolipid addition at a concentration of 160 mg/L provided similar results to those of an 80 mg/L addition. Finally, potential application of surfactin and rhamnolipid in stimulating indigenous microorganisms for enhanced bioremediation of diesel-contaminated soil was also examined. The results confirmed their enhancing capability on both efficiency and rate of diesel biodegradation in diesel/soil systems.     

聚天冬氨酸对铜、碳钢缓蚀性能的影响

采用失重法研究了pH=7.5的自来水中聚天冬氨酸和苯骈三唑、钼酸钠、硅酸钠复配时对铜和碳钢-铜复合体系的缓蚀效果,试验表明:单一聚天冬氨酸和钼酸钠的缓蚀效果随其浓度的增加而增加;单一苯骈三唑的缓蚀效果随其浓度的增加其缓蚀性也增加,当浓度达3 mg/L时,缓蚀效果最佳;单一硅酸钠的缓蚀效果随其浓度的增加其缓蚀性也增加,当浓度达200 mg/L时,缓蚀效果最佳;在缓蚀剂总浓度为50.5 mg/L时4种药剂复配,显示出较好的协同效应,其最佳配比为10 mg/L聚天冬氨酸 0.5 mg/L苯骈三唑 10 mg/L钼酸钠 30 mg/L硅酸钠.电化学动电位极化曲线测试结果表明复合水处理剂对阳极、阴极均有缓蚀作用.