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Comparative sensing of aldehyde and ammonia vapours on synthetic polypyrrole-Sn(IV)arsenotungstate nanocomposite cation exchange material 合成聚吡咯-钨酸砷-锡纳米复合阳离子交换材料上醛、氨蒸气的比较传感
Pub Date : 2017-06-01 DOI: 10.1016/j.ancr.2017.02.003
Asif Ali Khan , Rais Ahmad , Mohd. Zeeshan

Polypyrrole-Sn(IV)arsenotungstate (PPy-SnAT) conductive nanocomposite cation exchange have been synthesized by in-situ chemical oxidative polymerization of polypyrrole with Sn(IV)arsenotungstate (SnAT). PPy-SnAT nanocomposite was characterized by Fourier transform infra-red spectroscopy (FTIR), X-Ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive x-ray (EDX) and thermogravimetric analysis (TGA). The ion exchange capacity (IEC) and DC electrical conductivity of nanocomposite was found to be 2.50 meq/g and 5.05 × 10−1 S/cm respectively. The nanocomposite showed appreciable isothermal stability in terms of DC electrical conductivity retention under ambient condition up to 130 °C. The nanocomposite cation exchange based sensor for detection of formaldehyde and ammonia vapours were fabricated at room temperature. It was revealed that the resistivity of the nanocomposite increases on exposure to higher percent concentration of ammonia and lower concentration of formaldehyde at room temperature (25 °C).

采用聚吡咯和钨酸锡(SnAT)原位化学氧化聚合的方法,合成了聚吡咯-锡(IV)钨酸砷(py -SnAT)导电阳离子交换纳米复合材料。采用傅里叶变换红外光谱(FTIR)、x射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、能量色散x射线(EDX)和热重分析(TGA)对PPy-SnAT纳米复合材料进行了表征。离子交换容量(IEC)和直流电导率分别为2.50 meq/g和5.05 × 10−1 S/cm。在高达130℃的环境条件下,纳米复合材料在直流电导电性方面表现出明显的等温稳定性。在室温条件下制备了用于甲醛和氨蒸汽检测的纳米复合阳离子交换传感器。结果表明,在室温(25℃)下,较高浓度的氨和较低浓度的甲醛对纳米复合材料的电阻率有较大的影响。
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引用次数: 5
Preparation and characterization of a novel Co(II) optode based on polymer inclusion membrane 基于聚合物包合膜的新型Co(II)光电器件的制备与表征
Pub Date : 2017-06-01 DOI: 10.1016/j.ancr.2017.02.001
Faiz Bukhari Mohd Suah

A greener analytical procedure based on automated flow through system with an optical sensor is proposed for determination of Co(II). The flow through system consisted of polymer inclusion membrane (PIM) containing potassium thiocyanate (KSCN) that was placed between the measuring cell and fixed with optical sensor probe as an optical sensor for monitoring of Co(II) at 625 nm. In the presence of Co(II) ions, the colourless membrane changes to blue. The sensing membrane was prepared by incorporating SCN into a non plasticized PIM. The prepared PIM were found to be homogenous, transparent and mechanically stable. The optode shows reversible optical response in the range of 1.00 × 10−6 – 1.00 × 10−3 mol L−1 with detection limit of 6.10 × 10−7 mol L−1. The optode can be regenerated by using 0.1 mol L−1 of ethylenediaminetetraacetic acid (EDTA). The main parameters of the computer controlled flow system incorporating the flow-through optode, a multi-port selection valve and peristaltic pump were optimized too. The calculated Relative Standard Deviation (R.S.D) of the repeatability and reproducibility of the method are 0.76% and 4.73%, respectively. This green system has been applied to the determination of Co(II) in wastewater samples with reduced reagents and samples consumption and minimum waste generation.

提出了一种基于光学传感器的自动流动系统的绿色分析方法,用于测定Co(II)。流动系统由含有硫氰酸钾(KSCN)的聚合物包合膜(PIM)组成,该包合膜放置在测量池之间,并固定有光学传感器探头作为光学传感器,用于监测625 nm处的Co(II)。在Co(II)离子存在下,无色膜变成蓝色。将SCN掺入未增塑的PIM中制备传感膜。制备的PIM均匀、透明、机械稳定。该光电器件在1.00 × 10−6 ~ 1.00 × 10−3 mol L−1范围内表现出可逆的光响应,检出限为6.10 × 10−7 mol L−1。用0.1 mol L−1的乙二胺四乙酸(EDTA)再生光刻片。对由通流二极管、多通道选择阀和蠕动泵组成的微机控制流量系统的主要参数进行了优化。方法重复性和重现性的相对标准偏差(rsd)分别为0.76%和4.73%。该绿色系统已应用于废水样品中Co(II)的测定,试剂和样品消耗减少,废物产生最少。
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引用次数: 22
Nano clay Ni/NiO nanocomposite new sorbent for separation and preconcentration dibenzothiophene from crude prior to UV–vis spectrophotometery determination 纳米粘土Ni/NiO纳米复合吸附剂用于原油中二苯并噻吩的分离和预富集
Pub Date : 2017-06-01 DOI: 10.1016/j.ancr.2017.02.002
Amineh Mashkuri , Asma Saljooqi , Zeinab Tohidiyan

In this work, Ni/Ni nanoparticles were immobilized on modified nanoclay then, the resultant nanocomposite was used as a sorbent for separation of dibenzothiophene. The concentration of dibenzothiophene was determined with UV–vis spectrophotometry at 287 nm. Different parameters affecting the separation of dibenzothiophene such as: the ratio of Ni/NiO nanoparticles to nanoclay, amounts of Ni/NiO nanoparticles and nanoclay, stirring time of dibenzothiophene solution on the sorbent, type of eluent, eluent volume, elution time, stirring time for preparing the sorbent were optimized. The obtained results were shown quantitative desorption of dibenzothiophene performed using ethanol as eluent. A linear concentration range of 0.5–15 mg/L was obtained with a detection limit of 0.047 mg/mL. The sorbent capacity was found to be 32 mg/g. Relative standard deviation was ±1.4 for six replicated determination of 5 mg/g of dibenzothiophene. The optimized procedure was successfully used for a crude oil sample.

将Ni/Ni纳米颗粒固定在改性的纳米粘土上,制备的纳米复合材料作为吸附剂用于分离二苯并噻吩。采用紫外-可见分光光度法在287 nm处测定二苯并噻吩的浓度。考察了Ni/NiO纳米颗粒与纳米粘土的比例、Ni/NiO纳米颗粒与纳米粘土的用量、二苯并噻吩溶液在吸附剂上的搅拌时间、洗脱液类型、洗脱液体积、洗脱时间、制备吸附剂的搅拌时间等对二苯并噻吩分离效果的影响。结果表明,以乙醇为洗脱液对二苯并噻吩进行了定量解吸。在0.5 ~ 15mg /L的线性浓度范围内,检出限为0.047 mg/mL。吸附量为32 mg/g。5 mg/g二苯并噻吩6次重复测定的相对标准偏差为±1.4。该优化方法成功地应用于原油样品。
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引用次数: 7
Multivariate methods for analysis of environmental reference materials using laser-induced breakdown spectroscopy 用激光诱导击穿光谱分析环境标准物质的多变量方法
Pub Date : 2017-06-01 DOI: 10.1016/j.ancr.2017.01.001
Shikha Awasthi , Rohit Kumar , Alamelu Devanathan , R. Acharya , A.K. Rai

Analysis of emission from laser-induced plasma has a unique capability for quantifying the major and minor elements present in any type of samples under optimal analysis conditions. Chemometric techniques are very effective and reliable tools for quantification of multiple components in complex matrices. The feasibility of laser-induced breakdown spectroscopy (LIBS) in combination with multivariate analysis was investigated for the analysis of environmental reference materials (RMs). In the present work, different (Certified/Standard) Reference Materials of soil and plant origin were analyzed using LIBS and the presence of Al, Ca, Mg, Fe, K, Mn and Si were identified in the LIBS spectra of these materials. Multivariate statistical methods (Partial Least Square Regression and Partial Least Square Discriminant Analysis) were employed for quantitative analysis of the constituent elements using the LIBS spectral data. Calibration models were used to predict the concentrations of the different elements of test samples and subsequently, the concentrations were compared with certified concentrations to check the authenticity of models. The non-destructive analytical method namely Instrumental Neutron Activation Analysis (INAA) using high flux reactor neutrons and high resolution gamma-ray spectrometry was also used for intercomparison of results of two RMs by LIBS.

分析激光诱导等离子体的发射具有独特的能力,可以在最佳分析条件下定量任何类型样品中的主要和次要元素。化学计量学技术是一种非常有效和可靠的工具,可以定量分析复杂矩阵中的多种组分。探讨了激光诱导击穿光谱(LIBS)与多变量分析相结合用于环境标准物质(RMs)分析的可行性。本文利用LIBS分析了土壤和植物来源的不同(认证/标准)标准物质,并在这些物质的LIBS光谱中鉴定了Al, Ca, Mg, Fe, K, Mn和Si的存在。采用多元统计方法(偏最小二乘回归和偏最小二乘判别分析)对LIBS光谱数据进行定量分析。校准模型用于预测测试样品中不同元素的浓度,随后将浓度与认证浓度进行比较,以检查模型的真实性。利用高通量反应堆中子和高分辨率伽玛能谱的仪器中子活化分析(INAA)等非破坏性分析方法,对两种RMs的LIBS结果进行了比对。
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引用次数: 17
Characterization of methyl ester compound of biodiesel from industrial liquid waste of crude palm oil processing 棕榈油加工工业废液中生物柴油甲酯类化合物的表征
Pub Date : 2017-06-01 DOI: 10.1016/j.ancr.2017.01.002
Maulidiyah, Muhammad Nurdin, Fetty Fatma, Muh. Natsir, Dwiprayogo Wibowo

The second generation of Bioenergy: a study of CPO liquid waste-based biodiesel production technology has been conducted. The aims of this study were to obtain biodiesel from Industrial liquid waste of CPO processing and to identify the kind of methyl-ester compound of the biodiesel. The production of biodiesel was applied in two steps of reactions; esterification reaction using H2SO4 and transesterification using CaO catalyst at 60 °C for 2 h. GC-MS analysis result showed that methyl ester from liquid waste of CPO contains methyl hexadecanoate 12.87%, methyl 9-octadecanoate 19.98%, methyl octadecanoate 5.71%, and methyl 8,11-octadecadienoate 10.22%.

第二代生物能源:对CPO废液生物柴油生产技术进行了研究。本研究的目的是从CPO加工的工业废液中提取生物柴油,并对生物柴油的甲酯类化合物进行鉴定。采用两步反应制备生物柴油;用H2SO4进行酯化反应,用CaO催化剂在60℃下进行酯交换反应2 h。GC-MS分析结果表明,CPO废液的甲酯中十六酸甲酯含量为12.87%,9-十八酸甲酯含量为19.98%,十八酸甲酯含量为5.71%,8,11-十八酸甲酯含量为10.22%。
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引用次数: 54
A convenient colorimetric and ratiometric fluorescent probe for detection of cyanide based on BODIPY derivative in aqueous media 一种简便的基于BODIPY衍生物的比色和比例荧光探针,用于检测水介质中氰化物
Pub Date : 2017-06-01 DOI: 10.1016/j.ancr.2017.01.004
Yanhua Yu , Tingting Shu , Changzhi Dong

A convenient colorimetric and ratiometric fluorescent probe based on BODIPY derivative for cyanide detection has been synthesized, whose structural contains a dicyanovinyl group used as a sensing unit. Among the tested analytes, such as CN, F, Cl, Br, I, ClO4, AcO, NO3, H2PO4 HSO4, S2 and N3, only CN could react with dicyanovinyl moiety by nucleophilic addition, which disrupted the π-conjugation of the probe and hindered the intramolecular charge transfer (ICT), leading a blue shift of absorption and fluorescence spectrum and a concomitant color change from yellow to light pink. The detection limit of this probe was calculated to be 0.98 μM, which is lower than the maximum concentration in drinking water (1.9 μM) permitted by the World Health Organization (WHO). Moreover, the probe showed excellent selectivity and anti-interference ability towards CN over other anions. The reaction mechanism was fully supported by 1H NMR and MS spectrum.

合成了一种基于BODIPY衍生物的简便比色比比荧光探针,该探针结构中含有一个双氰乙烯基作为传感单元。在CN−、F−、Cl−、Br−、I−、ClO4−、AcO−、NO3−、H2PO4−、HSO4−、S2−和N3−等分析物中,只有CN−能够通过亲核加成与双氰乙烯基部分反应,破坏探针的π共轭,阻碍分子内电荷转移(ICT),导致吸收光谱和荧光光谱发生蓝移,颜色由黄色变为浅粉色。该探针的检出限为0.98 μM,低于世界卫生组织(WHO)规定的饮用水中最大浓度(1.9 μM)。此外,该探针对CN−的选择性和抗干扰能力优于其他阴离子。反应机理得到了1H NMR和MS谱的充分支持。
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引用次数: 9
Chemically modified carbon paste ion-selective electrodes for determination of atorvastatin calcium in pharmaceutical preparations 化学修饰碳糊离子选择电极测定药物制剂中阿托伐他汀钙
Pub Date : 2017-06-01 DOI: 10.1016/j.ancr.2017.06.001
Salwa Fares Rassi

A simple, rapid and sensitive method for the determination of atorvastatin calcium in pharmaceutical preparations using two modified carbon paste electrodes was developed. One electrode (sensor A) is based on ion-pair of atorvastatin with 5,6-diaminouracil hydrochloride (ATS-DAUH) and the other (sensor B) is based on atorvastatin with picric acid (ATS-PC). Among three different solvent mediators tested, dioctylphthalate (DOPH) exhibited a proper behavior including Nernstian slopes of the calibration curve at 58.76 ± 0.8 and 57.48±1 mV per decade for sensors A and B. The response times were 10 and 12 s, detection limits 1.3 × 10−6 and 2.2 × 10−6 M; the concentration range 2.5 × 10−6-7.9 × 10−2 M and 3.0 × 10−6 to 7.9 × 10−2 M respectively. The present electrodes show good discrimination of atorvastatin calcium from several inorganic, organic ions, sugars and some common excipients. The sensors were applied for the determination of atorvastatin calcium in pharmaceutical preparations using standard addition and the calibration curve methods. The results obtained were satisfactory with excellent percentage recovery comparable and sometimes better than those obtained by other routine methods for the assay. The proposed potentiometric methods offer the advantages of simplicity, accuracy, automation feasibility and applicability to turbid and colored sample solutions.

建立了一种简单、快速、灵敏的双改性碳糊电极测定药物制剂中阿托伐他汀钙的方法。一个电极(传感器A)基于阿托伐他汀- 5,6-二氨基尿嘧啶盐酸盐离子对(ATS-DAUH),另一个电极(传感器B)基于阿托伐他汀-苦味酸(ATS-PC)。在三种不同的溶剂介质中,苯二甲酸二辛酯(DOPH)对传感器a和b的校准曲线的Nernstian斜率分别为58.76±0.8和57.48±1 mV / decade,响应时间分别为10和12 s,检出限分别为1.3 × 10−6和2.2 × 10−6 M;浓度范围分别为2.5 × 10−6 ~ 7.9 × 10−2 M和3.0 × 10−6 ~ 7.9 × 10−2 M。该电极对阿托伐他汀钙与几种无机离子、有机离子、糖和一些常见赋形剂具有良好的分辨能力。采用标准添加法和校准曲线法,将传感器应用于药物制剂中阿托伐他汀钙的测定。所得结果令人满意,回收率极好,可与其他常规方法相媲美,有时甚至更好。所提出的电位法具有简单、准确、自动化可行性和适用于混浊和有色样品溶液的优点。
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引用次数: 8
Structural identification and estimation of Rosuvastatin calcium related impurities in Rosuvastatin calcium tablet dosage form 瑞舒伐他汀钙片剂型中瑞舒伐他汀钙相关杂质的结构鉴定与评价
Pub Date : 2017-06-01 DOI: 10.1016/j.ancr.2016.11.002
Chamarthi R.P. Kishore, G.V. Krishna Mohan

A precise, accurate, specific, linear, rugged and robust analytical method was developed and validated for estimation of process and degradant impurities of Rosuvastatin calcium (RSC) in Rosuvastatin calcium tablets. 150 mm length column, 4.6 mm diameter and 3.5μ particle size with C18 stationary phase and pH3.0 phosphate buffer as mobile phase. Column was maintained at 30 °C.All impurities are monitored at 248 nm.Impurities are separated in gradient elution mode. All degradant impurities of RSC (Anti-isomer, 5-ketoacid, lactone and meglumine adduct), process impurity (Imp-A) are well separated. Unknown impurity (Meglumine adduct) formed during stability studies was isolated using preparative HPLC and structure was characterized by NMR and Mass spectrometry (LC-MS and HRMS) studies. Method is capable of separating and estimating all the degradant and process impurities.

建立了瑞舒伐他汀钙片中瑞舒伐他汀钙(RSC)的工艺及降解杂质的定量分析方法,并进行了验证。柱长150mm,柱径4.6 mm,粒径3.5μ,以C18固定相和pH3.0磷酸盐缓冲液为流动相。柱保持在30°C。所有杂质都在248纳米处监测。以梯度洗脱的方式分离杂质。RSC的所有降解杂质(抗异构体、5-酮酸、内酯和三聚氰胺加合物)和工艺杂质(Imp-A)都得到了很好的分离。稳定性研究过程中形成的未知杂质(Meglumine加合物)采用制备型高效液相色谱(HPLC)分离,结构采用NMR和质谱(LC-MS和HRMS)研究。该方法能够分离和估计所有降解和工艺杂质。
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引用次数: 13
Sensors based on Ag-loaded hematite (α-Fe2O3) nanoparticles for methyl mercaptan detection at room temperature 基于载银赤铁矿(α-Fe2O3)纳米颗粒的室温甲基硫醇检测传感器
Pub Date : 2017-06-01 DOI: 10.1016/j.ancr.2016.12.001
Daniel Garcia , Gino Picasso , Pilar Hidalgo , Henrique E.M. Peres , Rosario Sun Kou , Josué M. Gonçalves

Sensors based on Ag/α-Fe2O3 nanoparticles have been prepared by the coprecipitation method for sensing methyl mercaptan at room temperature. X-ray diffraction patterns of samples matched perfectly with characteristic peaks of hematite with no peaks assigned to Ag even at the highest concentration. STEM images and EDX analysis revealed the presence of Ag nanoparticles (from 2 to 5 nm) which were highly dispersed onto α-Fe2O3 surface with an Ag/Fe ratio from 0.014 to 0.099. The Ag nanoparticles were deposited on the hematite surface. Sensing tests of Ag-loaded hematite nanoparticles showed much higher response signal than the unmodified sensor. Hematite loaded with 3%(Wt) Ag showed the highest response with a linear dependence from 20 to 80 ppm. The sensor also depicted a good selectivity and stability during 4 days with short recovery time. The high dispersion of reduced Ag evaluated by XPS analysis played an important chemical role in the sensing mechanism that favored the contact of CH3SH with oxygen.

采用共沉淀法制备了Ag/α-Fe2O3纳米颗粒的室温甲基硫醇传感器。样品的x射线衍射图与赤铁矿的特征峰完全匹配,即使在最高浓度下也没有银峰。STEM图像和EDX分析显示,α-Fe2O3表面存在2 ~ 5 nm的Ag纳米颗粒,Ag/Fe比值为0.014 ~ 0.099。银纳米颗粒沉积在赤铁矿表面。负载银纳米赤铁矿的传感实验表明,传感器的响应信号明显高于未修饰的传感器。负载3%(Wt) Ag的赤铁矿表现出最高的响应,在20到80 ppm之间呈线性相关。该传感器在4天内具有良好的选择性和稳定性,恢复时间短。XPS分析表明,还原银的高度分散在有利于CH3SH与氧接触的传感机制中发挥了重要的化学作用。
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引用次数: 36
An assessment of different extraction and quantification methods of penta- and hexa-chlorobenzene from SRF fly-ash SRF粉煤灰中五氯苯和六氯苯不同提取和定量方法的评价
Pub Date : 2017-06-01 DOI: 10.1016/j.ancr.2017.01.003
Dimitris E. Balampanis, Frédéric Coulon, Nigel Simms, Philip Longhurst, Simon J.T. Pollard, Cecilia Fenech, Raffaella Villa

Highly chlorinated benzenes, produced in the presence of organic matter and chlorine, are considered PCDD/Fs precursors, and are used as cost and time convenient substitute indicators for the indirect measurement of the latter. In this study penta- and hexa-chlorobenzene are quantified for the determination of the organochloride load of fly ash from solid recovered fuel incineration. Some of the chlorobenzenes are formed under ‘de novo’ conditions, through heterogeneous (ash particles/flue gases) reactions and are therefore deeply incorporated within fly ash. Accelerated solvent extraction (ASE) and ultrasonic solvent extraction (USE), along with the equivalent clean-up methods suggested by literature were compared to traditional Soxhlet. The extraction efficiencies achieved were 83 ± 7.5% for Soxhlet, 111 ± 19% for PFE, and 67 ± 17% for ultrasonication. Soxhlet extraction and clean-up through a multilayer silica gel column gave more precise results compared to the other sample preparation methods. Furthermore, performance comparison of gas chromatography fitted with either a mass spectrometer operated in single ion monitoring mode (GC-MS-SIM), or electron capture detector (GC- ECD) highlighted that ECD can be used for measuring chlorobenzenes traces down to 0.21 ng g−1, when the equivalent LOQ for MS-SIM was 3.26 ng g−1. The results further suggest that ECD can provide better peak integration than MS-SIM in the detection of chlorobenzenes in fly ash extracts, due to the detector's sensitivity to halogenated compounds.

在存在有机物和氯的情况下产生的高氯化苯被认为是PCDD/Fs前体,并被用作间接测量后者的成本和时间方便的替代指标。在本研究中,五氯苯和六氯苯的定量用于测定固体回收燃料焚烧飞灰的有机氯负荷。有些氯苯是在“从头”条件下通过非均相(灰颗粒/烟道气)反应形成的,因此深深融入飞灰中。将加速溶剂萃取法(ASE)和超声溶剂萃取法(USE)以及文献中提出的等效清洗方法与传统索氏法进行了比较。索氏法提取率为83±7.5%,PFE法为111±19%,超声法为67±17%。与其他样品制备方法相比,通过多层硅胶柱进行索氏提取和清理的结果更为精确。此外,将单离子监测模式下的质谱仪(GC-MS-SIM)和电子捕获检测器(GC- ECD)的气相色谱性能进行比较,发现当MS-SIM的等效LOQ为3.26 ng g - 1时,ECD可用于测量低至0.21 ng g - 1的氯苯痕量。结果进一步表明,由于检测器对卤化化合物的敏感性,ECD比MS-SIM在检测粉煤灰提取物中氯苯方面可以提供更好的峰积分。
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引用次数: 4
期刊
Analytical Chemistry Research
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