四川蛇纹石猫眼的拉曼光谱及其颜色相关性

采用电子探针（EPMA）、激光拉曼（Raman）光谱、¹H-核磁共振谱（¹H-NMR）和电子顺磁共振吸收谱（EPR）对四川石棉县的蛇纹石猫眼进行了测试分析。结果表明：蛇纹石猫眼的主要平均化学组成（质量分数）为SiO₂ 43.56%,MgO 40.52%,FeO和Fe₂O₃混合物为2.14%,MnO 0.05%。其中,致色离子主要为顺磁离子Fe³⁺和Mn²⁺;蛇纹石猫眼Raman谱峰中3 700 cm^-1附近的-OH谱带分裂,并向低波数方向位移,主要与其不同颜色样品成分中Fe³⁺和Mn²⁺的含量、占位以及Fe³⁺和Mn²⁺对Mg²⁺类质同象替换的程度有关;Fe³⁺和Mn²⁺同时占位于蛇纹石Mg-O（OH）八面体位置,随样品的颜色由浅黄绿色向暗褐绿色转变,Fe³⁺和Mn²⁺类质同象替代Mg²⁺的程度增强,从而使Mg-O（OH）八面体部分分裂为（（Fe³⁺、Mn²⁺）,Mg²⁺）-O（OH）八面体。¹H-NMR的测试结果也证实了这一点。     

羟胺促进柠檬酸-Fe2+活化过碳酸钠降解三氯乙烯

研究了柠檬酸（CA）螯合Fe²⁺活化过碳酸盐体系中投加盐酸羟胺（HAH）对三氯乙烯（TCE）的去除效果。结果发现,HAH能有效将Fe³⁺还原为Fe²⁺,强化TCE的去除效果。当TCE初始浓度为0.15 mmol/L时,n_SPC：n_Fe²⁺：n_TCE=5：3：1时,在CA浓度为0.5 mmol/L条件下,HAH最佳投加浓度为1.5 mmol/L,此时TCE去除率为99.6%。·OH对TCE降解的贡献度为79.2%,O₂^-·的贡献度为21.9%。HAH可减轻HCO₃^-对TCE降解的抑制效应,中间产物为甲酸、NO₂^-和NO₃^-。HAH利于SPC/Fe²⁺/CA体系降解TCE,该结果可为实际TCE污染地下水修复提供技术支撑。     

中空纤维膜反应器结合芬顿试剂脱除燃煤烟气中的Hg0

将中空纤维膜反应器和芬顿试剂结合脱除烟气中的Hg⁰。研究了不同参数以及SO₂、NO和O₂等杂质气体对Hg⁰脱除的影响。结果表明：随着H₂O₂浓度、Fe²⁺浓度、溶液初始pH和温度的增加,Hg⁰脱除率先增加后降低,其最佳工作条件是H₂O₂浓度为6 mmol/L,Fe²⁺浓度为9 mmol/L,溶液初始pH为2.5,温度为20℃;增大液气比和通过减小气相流量增大停留时间均对Hg⁰脱除有增强作用,当液气比超过0.11时,Hg⁰的脱除率不再增加;当气相流量为0.6 L/min时,Hg⁰脱除率超过85%;SO₂、NO对Hg⁰的脱除有抑制作用,O₂对Hg⁰的脱除几乎没有影响;还测定出温度20℃下中空纤维膜反应器的比相界面积a=270.29 m^-1和传质动力学参数k_L=8.13×10^-4 m/s,k_G=0.786×10^-6 mol/（m²·s·Pa）。     

mSiO2-IDA对Cu2+、Cd2+金属离子的吸附

在介孔二氧化硅（mSiO₂）的表面接枝了亚氨基二乙酸官能团（IDA）合成了mSiO₂-IDA吸附剂,研究了mSiO₂-IDA对Cu²⁺、Cd²⁺两种金属离子的吸附效果。通过元素分析仪（EA）、傅里叶红外型光谱仪（FT-IR）等表征手段表明IDA成功地接枝到mSiO₂的表面,考察了溶液的pH、初始浓度和吸附时间对吸附Cu²⁺、Cd²⁺的影响。结果显示,当pH=5,t=30 min时,2 g/L mSiO₂-IDA对溶液中的Cu²⁺、Cd²⁺去除率分别达到97.9%和92.1%。通过吸附动力学数据可知,拟二级动力学方程能更好地描述mSiO₂-IDA对Cu²⁺、Cd²⁺的吸附过程,它属于Langmuir等温吸附模型;多功能光电子能谱仪（XPS）研究显示mSiO₂-IDA对Cu²⁺、Cd²⁺的吸附机制并不相同。     

参麦注射液抗氧化活性体外实验研究

[目的] 系统研究参麦注射液体外抗氧化性能。[方法] 采用铁还原抗氧化能力 （FRAP）法、1,1-二苯基-2-三硝基苯肼（DPPH）自由基清除法、一氧化氮（NO）自由基清除法、过氧化氢（H₂O₂）清除法、亚铁（Fe²⁺）离子螯合法分别测试不同稀释倍率参麦注射液的总抗氧化能力、DPPH·清除活性、NO·清除活性、H₂O₂清除活性和Fe²⁺离子螯合活性,并将结果与0.1mg/mL 2,6-二叔丁基对甲酚（BHT）、10 mmol/L水溶性维生素E（Trolox）和10%柠檬酸的结果进行比较。[结果] 参麦注射液具有一定的体外抗氧化能力,总抗氧化能力和对自由基清除活性均呈浓度正依赖性;10倍稀释参麦注射液总抗氧化能力显著低于BHT和Trolox （P<0.01）,但高于柠檬酸（P<0.01）;参麦注射液对不同自由基清除能力存在差异,其强弱顺序为：NO·[（54.4±6.6）%] > Fe²⁺离子螯[（42.6±3.2）%] > DPPH·[（36.2±2.8）%] > H₂O₂[（23.5±1.2）%]。[结论] 参麦注射液体外抗氧化活性研究将为其抗氧化药理学机制提供了实验依据。     

不同来源葡萄糖氧化酶的分离纯化及其生物催化特性

采用离子交换层析法对4种不同来源的葡萄糖氧化酶（Glucose oxidase, GOD,EC 1.1.3.4）进行分离纯化,纯化后酶的相对分子质量约为130 kDu,为双亚基酶。纯化后的4种酶的酶学性质相对稳定,对pH有较宽的响应范围。温度为20～50℃时,随着温度的升高酶活降低且稳定性较好;温度为55℃时稳定性较差;而在60℃时则失活。金属离子如Fe²⁺、Co²⁺、Mg²⁺和Cu²⁺对4种酶都有较强的抑制作用,Fe²⁺的抑制尤其明显,而螯合剂EDTA可以激活酶的活性。在30℃、pH为7.0的条件下,以不同浓度（20～100 mmol/L）的葡萄糖为底物分别测定4种酶的米氏常数（K_m）和催化常数（K_cat）。通过光谱和色谱对4种葡萄糖氧化酶进行检测,虽然氨基酸组成有明显不同,但二维结构基本一致,而GOD前体goxC和修饰蛋白如过氧化氢酶、过氧化氢酶前体和Pc16g04630等可能是提高GOD催化效率和工业应用的分子基础。     

原位合成四氧化三锰处理模拟核电厂含Co2+放射性废水

在硼酸体系中,以⁵⁹Co作为模拟非放射性同位素研究了原位合成四氧化三锰处理模拟核电厂放射性废水中Co²⁺的工艺条件。考察了反应时间、n(Mn²⁺):n(Co²⁺)、空气流量、反应温度以及pH对出水Co²⁺质量浓度的影响,并由正交试验L₉(4³)优化工艺条件。研究表明:在废水Co²⁺初始质量浓度10mg/L,硼酸质量浓度(以B计)1000mg/L条件下,最佳工艺条件为反应时间105min、n(Mn²⁺):n(Co²⁺)=25:1、空气流量0.7L/min、反应温度65℃以及pH10.5,在此条件下出水Co²⁺质量浓度约为5.68ng/L,去除效率大于99.99%,产物经XRD分析证明沉渣为Mn₃O₄和CoMn₂O₄混合物。     

Li2SiO3:Eu3+红色荧光粉的制备与发光性能

以LiOH·H₂O、Si（OC₂H₅）₄和Eu（NO₃）₃·6 H₂O为主要原料,采用简单的机械球磨法,在室温下合成了Li₂SiO₃：Eu³⁺荧光粉前驱体,再经高温灼烧,得到一系列Li₂SiO₃：x% Eu³⁺红色荧光粉。研究了灼烧温度、保温时间及Eu³⁺的物质的量浓度对产物的结构和发光性能的影响。结果表明,当x在1.5~15这个较宽的范围内,随着Eu³⁺物质的量的增加,Li₂SiO₃：x% Eu³⁺荧光粉的物相组成保持不变,且直到x值达到12之后,才出现了浓度淬灭现象;当灼烧温度为1 173 K、保温时间为2 h时,荧光材料的发光强度达到最大值。在467 nm激发下,基于Eu³⁺的⁵D₀→⁷F₂（615 nm）跃迁,Li₂SiO₃：Eu³⁺荧光粉发射出强烈的红光。     

丁腈橡胶/硫酸铁配位交联复合材料的制备与表征

采用溶液球磨法制备了丁腈橡胶（NBR）/硫酸铁（Fe₂（SO₄）₃）复合材料,Fe₂（SO₄）₃颗粒的平均粒径由10.23 μm降低到1.13 μm,粒径大小分布变窄。电子顺磁共振谱（ESR）以及X射线光电子能谱分析（XPS）证明了丁腈橡胶中的-CN与Fe₂（SO₄）₃中的Fe³⁺发生了配位反应。随着Fe₂（SO₄）₃添加量的增加,复合材料的玻璃化转变温度（T_g）与交联密度逐渐增加。当Fe₂（SO₄）₃添加量为15 phr （每100份基体中的填料份数）时,NBR/Fe₂（SO₄）₃复合材料综合力学性能最好,复合材料的拉伸强度比纯NBR的拉伸强度提高了约12.8倍。采用溶液球磨法制备出的NBR/Fe₂（SO₄）₃复合材料的交联密度、拉伸强度、硬度、回弹性、伸张疲劳系数以及耐老化性能均高于干法制备的NBR/Fe₂（SO₄）₃复合材料的相应值。     

不同金属离子对竹黄液体发酵的影响

目的 研究不同质量分数的Cu²⁺、Fe³⁺、Cr³⁺和Ca²⁺对竹黄菌液体发酵产竹红菌素量和菌丝体生物量的影响。方法 向培养基中添加不同质量分数的金属离子,在27 ℃、130 r/min下培养96 h。结果 Cr³⁺的质量分数为0.005%时竹红菌素及菌丝体生物量最大;Fe³⁺的质量分数为0.003%时菌丝体生物量最高,0.005%时竹红菌素量最高;Ca²⁺的质量分数为0.03%时最有利于菌丝体生长,0.05%时最能促进竹红菌素的分泌;Cu²⁺的质量分数为0.03%时生物量及竹红菌素量均达到最大值。结论 添加金属离子后,菌丝体干质量最高达15.28 g/L,竹红菌素量最高达8.12 mg/g。     

基于化学动力学的异绿原酸A在水溶液中的降解规律研究

[目的]研究异绿原酸A在水溶液中,于不同pH值、温度、光照、初始药物浓度等条件下的降解动力学特征。[方法]采用超高液相色谱(UPLC)法考察不同环境下异绿原酸A含量随时间的变化情况,以化学反应动力学方法计算不同条件下的降解半衰期(t1/2)等反应动力学参数,利用Arrhenius方程计算降解反应的活化能。[结果]异绿原酸A在多种条件下的降解均符合一级动力学模型,降解速率呈现pH和温度依赖性;金属离子Fe~(3+)、Fe~(2+)的引入以及紫外光均会使异绿原酸A的降解反应速率加快,而初始药物浓度及氧化的变化对其降解速率影响不明显。在25℃,中性条件下异绿原酸A的降解活化能为96.71 kJ/mol,t_1/2为1 381.9 h。[结论]异绿原酸A在酸性,低温环境中较为稳定,高温、强碱、活波金属离子及紫外光均可加速其降解。异绿原酸A在中药材及中成药中广泛存在,此类药物在生产、储存和使用过程中应避免含铁容器,应选择在低温、避光环境下保存。     

Pre-concentration and determination of amitriptyline residues in waste water by ionic liquid based immersed droplet microextraction and HPLC

This paper describes a new approach for the determination of amitriptyline in wastewater by ionic liquid based immersed droplet microextraction (IL-IDME) prior to high-performance liquid chromatography with ultraviolet detection. 1-Hexyl-3-methylimidazolium hexafluorophosphate ([C₆MIM][PF₆]) was used as an ionic liquid. Various factors that affect extraction, such as volume of ionic liquid, stirring rate, extraction time, pH of the aqueous solution and salting effect, were optimized. The optimal conditions were as follows: microextraction time, 10 min; stirring rate, 720 rpm; pH, 11; ionic drop volume, 100 μL; and no sodium chloride addition. In quantitative experiments the method showed linearity in a range from 0.01 to 10 μg/mL, a limit of detection of 0.004 μg/mL and an excellent pre-concentration factor (PF) of 1100. Finally, the method was successfully applied to the determination of amitriptyline in the hospital wastewater samples.     

An ionic liquid supported CeO2 nanoparticles–carbon nanotubes composite-enhanced electrochemical DNA-based sensor for the detection of Pb2+

An electrochemical sensor incorporating a signal enhancement for the determination of lead (II) ions (Pb²⁺) was designed on the basis of the thrombin-binding aptamer (TBA) as a molecular recognition element and ionic liquid supported cerium oxide (CeO₂) nanoparticles–carbon nanotubes composite modification. The composite comprises nanoparticles CeO₂, multi-wall carbon nanotubes (MWNTs) and hydrophobic room temperature ionic liquid (RTIL) 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF₄). The electrochemical sensors were fabricated by immersing the CeO₂–MWNTs–EMIMBF₄ modified glassy carbon electrode (GCE) into the solution of TBA probe. In the presence of Pb²⁺, the TBA probe could form stable G-quartet structure by the specific binding interactions between Pb²⁺ and TBA. The TBA-bound Pb²⁺ can be electrochemically reduced, which provides a readout signal for quantitative detection of Pb²⁺. The reduction peak current is linearly related to the concentration of Pb²⁺ from 1.0×10^–8 M to 1.0×10^–5 M with a detection limit of 5×10^–9 M. This work demonstrates that the CeO₂–MWNTs–EMIMBF₄ nanocomposite modified GCE provides a promising platform for immobilizing the TBA probe and enhancing the sensitivity of the DNA-based sensors.     

Dispersive liquid-liquid microextraction combined with high-performance liquid chromatography for the determination of clozapine and chlorpromazine in urine

A simple method has been proposed for the determination of clozapine (CLZ) and chlorpromazine (CPZ) in human urine by dispersive liquid-liquid microextraction (DLLME) in combination with high-performance liquid chromatography-ultraviolet detector (HPLC-UV). All important variables influencing the extraction efficiency, such as pH, types of the extraction solvent and the disperser solvent and their volume, ionic strength and centrifugation time were investigated and optimized. Under the optimal conditions, the limit of detection (LODs) and quantification (LOQs) of the method were 13 and 39 ng/mL for CLZ, and 2 and 6 ng/mL for CPZ, respectively. The relative standard deviations (RSDs) of the targets were less than 5.1% (C=0.100 μg/mL, n=9). Good linear behaviors over the tested concentration ranges were obtained with the values of R2>0.999 for the targets. The absolute extraction efficiencies of CLZ and CPZ from the spiked blank urine samples were 98.3% and 97.8%, respectively. The applicability of the technique was validated by analyzing urine samples and the mean recoveries for spiked urine samples ranged from 93.3% to 105.0%. The method was successfully applied for the determination of CLZ and CPZ in real human urine.     

明胶-环氧聚醚胺交联膜的合成及其对重金属离子的吸附性能

首先利用聚乙二醇二缩水甘油醚(PEO-DE)、聚二甲基硅氧烷二缩水甘油醚(PDMS-DE)与无水哌嗪以1:1:1的物质的量之比反应合成环氧封端的聚醚胺(ePEA),然后将ePEA分散在水相中与明胶混合,浇铸固化成膜。利用红外光谱(FT-IR)、X射线衍射(XRD)、示差扫描量热法(DSC)和原子吸收光谱(AAS)等手段研究了明胶-环氧聚醚胺交联膜的结构和离子吸附性能。结果表明,与纯明胶膜相比,交联膜中的环氧聚醚胺与明胶之间出现了新的化学交联结构,在水溶液中的稳定性提高;交联膜对Cu²⁺、Pb²⁺、Cd²⁺均有一定的吸附作用,并且吸附能力随着ePEA含量的增加而增加;吸附过程符合二级动力学模型和Langmuir等温模型。     

Extraction and determination of trace amounts of chlorpromazine in biological fluids using magnetic solid phase extraction followed by HPLC

A simple, rapid and sensitive method termed as magnetic solid phase extraction (MSPE) combined with high-performance liquid chromatography-ultraviolet detector (HPLC-UV) has been proposed for the determination of trace amounts of chlorpromazine (CPZ) in water, urine and plasma samples. The separation and determination was performed on a C18 column under the optimal chromatographic conditions. Several factors influencing the extraction efficiency of CPZ, such as pH, surfactant and adsorbent amounts, ionic strength, extraction time, sample volume and desorption conditions, were studied and optimized. Under the optimal MSPE conditions, the extraction percentage of CPZ was 74%, 27% and 16% in water, urine and plasma samples, respectively. The limits of detection (LODs) of the proposed approach were 0.1, 5.0 and 10 ng/mL in water, urine and plasma samples, respectively. The relative standard deviations (RSDs) based on five replicate determinations at 10 ng/mL level of CPZ was 1.2%. Good linear behaviors over the investigated concentration ranges (0.25–300 ng/mL) with good coefficient of determination, R²>0.9998, were obtained. Good spike recoveries with relative errors less than 9.0% were obtained when applying the proposed method to water, urine and plasma samples.     

荧光分析法测定元宝枫叶中总黄酮含量的研究

目的 采用荧光分析方法,对元宝枫叶总黄酮含量进行测定研究.方法 以芦丁为标准对照品,利用黄酮与Al3＋形成稳定荧光络合物的性质,选择激发波长λex=470 nm,发射波长λem=547 nm,研究乙醇的体积分数、5%Al（NO3）3的加入量、pH、放置时间以及绿原酸对荧光强度的影响.结果最佳测定条件是以60%乙醇溶液作为溶剂,在10 mL的容量瓶中加入1 mL 5% Al（NO3）3,并使测定溶液pH=5.该方法测定芦丁质量浓度在6.55×10-6mol/L～3.20×10-5mol/L与荧光强度具有良好的线性关系,且回归方程为y=1.147 7x ＋ 0.430 4,R2=0.999 1.结论 采用荧光分析法,通过改变激发光的波长,能够减小绿原酸对黄酮测定的干扰,可作为元宝枫叶总黄酮含量测定的参考方法.     

Alteration of chemical behavior of L-ascorbic acid in combination with nickel sulfate at different pH solutions in vitro

Objective

To evaluate the alteration of chemical behavior of L-ascorbic acid (vitamin C) with metal ion (nickel) at different pH solutions in vitro.

Methods

Spectra of pure aqueous solution of L-ascorbic acid (E mark) compound and NiSO₄ (H₂O) (sigma USA) were evaluated by UV visible spectrophotometer. Spectral analysis of L-ascorbic acid and nickel at various pH (2.0, 7.0, 7.4 and 8.6) at room temperature of 29 °C was recorded. In this special analysis, combined solution of L-ascorbic acid and nickel sulfate at different pH was also recorded.

Results

The result revealed that λ_max (peak wavelength of spectra) of L-ascorbic acid at pH 2.0 was 289.0 nm whereas at neutral pH 7.0, λ_max was 295.4 nm. In alkaline pH 8.6, λ_max was 295.4 nm and at pH 7.4 the λ_max of L-ascorbic acid remained the same as 295.4 nm. Nickel solution at acidic pH 2.0 was 394.5 nm, whereas at neutral pH 7.0 and pH 7.4 were the same as 394.5 nm. But at alkaline pH 8.6, λ_max value of nickel sulfate became 392.0 nm. The combined solution of L-ascorbic acid and nickel sulfate (6 mg/mL each) at pH 2.0 showed 292.5 nm and 392.5 nm, respectively whereas at pH 7.0, L-ascorbic acid showed 296.5 nm and nickel sulfate showed 391.5 nm. At pH 7.4, L-ascorbic acid showed 297.0 nm and nickel sulfate showed 394.0 nm in the combined solution whereas at pH 8.6 (alkaline) L-ascorbic acid and nickel sulfate were showing 297.0 and 393.5 nm, respectively.

Conclusions

Results clearly indicate an altered chemical behavior of L-ascorbic acid either alone or in combination with nickel sulfate in vitro at different pH. Perhaps oxidation of L-ascorbic acid to L-dehydro ascorbic acid via the free radical (HSc*) generation from the reaction of H₂ASc + Ni (II) is the cause of such alteration of λ_max value of L-ascorbic acid in the presence of metal nickel.