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91.
A new simple sensitive differential pulse polarographic (DPP) method was investigated for the determination of acrylamide (AA) directly in a neutral aqueous solution. The AA showed a well-defined and well-resolved peak in pure aqueous LiCl at −1.84 V in the potential range from −1.6 V to −1.97 V at nitrogen pressure of 0.5 kg cm−2. Among the various electrolytes studied, the AA showed good DPP response in the presence of LiCl and tetra methyl ammonium iodide, while it showed poor response in the presence of tetra butyl ammonium hydroxide and tetra butyl ammonium bromide due to their strong adsorption on the surface of electrode which hindered its reduction. The effect of LiCl concentration, the cyclic voltammetric response and the drop time study showed that AA exhibited an irreversible adsorptive electrochemical behavior. The good electrochemical response in pure aqueous medium suggested that hydrogen bonding might be involved which may favor the electrode reaction. Under optimized conditions, the peak current was linear in the entire concentration range from 0.2 mg L−1 to 20 mg L−1 with the correlation coefficient of R2 = 0.9998. The method showed good reproducible results with R.S.D. of 0.3% (n = 16). The detection limit (LOD) was 27 μg L−1. The influence of various interfering agents was also studied. The method was applied successfully for the quantification of AA in water samples without any interference effect from alkali metals. 相似文献
92.
XU Liang-zhong XU Zhong-jie ZHANG Gong-sheng ZHOU Kai ZHAI Zhi-wei College of Chemistry Molecule Engineering Qingdao University of Science Technology Qingdao P. R. China 《高等学校化学研究》2008,24(5):575-578
With dimethomorph and flumorph as the leading compounds, four novel acrylamide compounds with two types of structure were designed and synthesized by means of the method of "me too chemistry". The target compounds were characterized by 1H NMR, IR, MS, and elemental analysis. The influences of solvent and raw material on the yield were investigated and optimum processing conditions were determined. The results of preliminary biological tests show that all those compounds exhibit certain antifungal activities. 相似文献
93.
《印度化学会志》2023,100(1):100850
Molecular imprinted polymers (MIPs) are polymers that possess recognition sites specific for a predetermined target molecule (Template). Inspired by the idea of biological natural receptors, they behave like synthetic molecular recognition elements. They have been developed into a promising tool in several crucial applications, including analytical methods, drug delivery, and catalysis. The non-covalent imprinting is more commonly used approach in the preparation of MIPs because of its simplicity. In this approach, intermolecular interactions between the template molecule (T) and the functional monomer (FM) are the forces that govern the performance of the resulting MIP. Hence, studying these interactions is very important to elucidate and understand the imprinting mechanism. This paper focuses on preparation of two MIPs for a Clidinium Bromide (CB), using two different types of FMs. These MIPs are characterized by using IR and SEM techniques. Adsorption isotherm properties to CB are assayed for them. Then the structures of the pre-polymerization complexes of prepared MIPs were investigated using Density Functional Theory (DFT) calculations at B3LYP/6-31G level in a vacuum and other media. Finally, Bader's Quantum Theory of Atoms in Molecules (QTAIM) was used to prove the existence and nature of intermolecular interactions between CB and FM. The theoretical results were in complete agreement with experiments and indicated that the use of AM as FM is preferred over MA in the MIP preparation for CB. 相似文献
94.
《Journal of Saudi Chemical Society》2023,27(1):101587
Deterioration of water quality has become an ecological threat in many industrial areas worldwide due to unmanaged anthropogenic activities. Contaminants therein find out their ways to drinking water-pipes via broken or leak old- pipes. The current study aims at evaluating the suitability of tap water, collected from the main-ten-industrial cities of Egypt, for drinking purposes. Shallow and deep ground waters were also sampled from the same locations. This is one of the few research projects that are interested in quantifying the acrylamide in drinking water. The obtained results indicate that concentrations of COD, BOD, Fe, Mn, Ni, Pb, Cd, Zn and Hg were within the permissible levels in tap water while surpassed these levels in both shallow and deep ground waters. Acrylamide levels did not exceed the acceptable levels in all water samples (drinking, surface and deep ground waters). Overall, no potential risks were associated with the oral ingestion of tap water in all studied locations for both adults and children (all hazard quotient (HQ) values, defined as exposure intake dose of contaminants relative to the maximum permissible daily intake dose were below “1″). However, inorganic pollutants that exist in ground waters may cause undesirable dermal impacts when used for irrigating the green areas in these cities (used for picnics and as playgrounds). In this context, most HQ values associated with ground water dermal contact were above “1”. Specifically, Mn, Ni, Pb and Cd hazards exist for children (HQ > 1) while Ni, Pb and Cd toxicity detected for adults. This result; therefore, highlights the indirect negative impacts of industrialization on human health. 相似文献
95.
首先研究了高分子阳离子乳化剂的合成,其中以苯乙烯(St)和丙烯酰胺(AM)为主单体,十六烷基三甲基溴化铵(CTAB)为相转移乳化助剂,环氧氯丙烷(ECH)、三甲胺为季铵化试剂。最终确定当CTAB用量为1g,AM用量为5g,ECH用量为5.2g时,所得到的乳化剂的乳化性能最优良。对不同功能性单体对阳离子乳液涂膜吸水率与粒径的影响做了研究,结果表明:当加入交联体系双丙酮丙烯酰胺-己二酰肼基丙烯酸酯(DAAM-ADH)为1.0g时,吸水率达到最低值5.39%。最后通过加入三氧化二铝分散液制得核壳结构乳液,结果表明:当加入三氧化二铝分散液20g时,所得到的乳液包裹性能最好,乳液较稳定。 相似文献
96.
A method has been developed to determine acrylamide in aqueous matrices by using direct immersion solid-phase microextraction (SPME) coupled to gas chromatography-positive chemical ionization tandem mass spectrometry (GC-PCI-MS-MS) in the selected reaction monitoring (SRM) mode. The optimized SPME experimental procedures to extract acrylamide in water solutions were: use of a carbowax/divinylbenzene (CW/DVB)-coated fiber at pH 7, extraction time of 20 min and analyte desorption at 210 °C for 3 min. A detection limit of 0.1 μg L−1 was obtained. The linear range was 1-1000 μg L−1. The relative standard deviation was 10.64% (n = 7). The proposed analytical method was successfully used for the quantification of trace acrylamide in foodstuffs such as French fries (1.2 μg g−1) and potato crisps (2.2 μg g−1). 相似文献
97.
98.
Nattawut Limparyoon Nispa Seetapan Suda Kiatkamjornwong 《Polymer Degradation and Stability》2011,96(6):1054-1063
Acrylamide (AM) and 2-acrylamido-2-methylpropane sulfonic acid (AMPS-H+) or its sodium salt (AMPS-Na+) were copolymerised by free-radical crosslinking polymerization to obtain poly(AM-co-AMPS-H+) and poly(AM-co-AMPS-Na+) superabsorbent polymers (SAPs). A maximum water absorbency in deionised water of 1200 g g−1 was achieved for poly(AM-co-AMPS-Na+) at a 85% mol of AMPS-Na+. The inclusion of mica at 5-30% (w w−1) into the preparation of poly(AM-co-AMPS-Na+) SAP leads to an intercalated structure, as detected by XRD and TEM analyses. Poly(AM-co-AMPS-Na+)/30% (w w−1) mica SAP nanocomposite showed a tap water absorbency of 593 g g−1 with a better thermal stability, compared to the pure SAP. Cone calorimetric analyses revealed that the wood specimens coated with the prepared poly(AM-co-AMPS-Na+) SAP or its 30% (w w−1) mica nanocomposite provided excellent protection in delaying the ignition time after exposure to an open flame when compared to that observed with the uncoated specimen. The maximum reduction in the peak heat release rate and the greatest extension of time at peak heat release rate were observed with the nanocomposite-coated surface, but the total heat release rate was increased. The delayed burning mechanism is brought by the intercalating structure of mica in the SAP nanocomposites, which provided a better shielding effect against external heat sources, and the capability of the SAP nanocomposite in holding a large amount of water. 相似文献
99.
12%acrylamide(AM) was grafted onto the surface of nanocellulose whiskers(NCW),which was self-assembled to be the chiral nematic suspension at 3%content.The acrylamide grafted NCW(AM-g-NCW) was characterized with Fourier Transform Infrared Spectroscopy(FTIR).The grafting ratio was measured by elemental analysis.The degrees of crystallinity of the AM-g-NCW were measured by X-ray diffraction(XRD).The liquid crystalline properties of the AM-g-NCW were investigated by the polarizing optical microscopy(POM).The AM-g-NCW was found to self-assembly to be a lyotropic state. 相似文献
100.
《Analytical letters》2012,45(10):1407-1417
Abstract Square-wave voltammetry is a fast technique used for determination of trace amounts of acrylamide. When cobalt(II) ions were added to the acrylamide solution, a catalytic peak at about ?1.35 V vs. Ag/AgCl was observed, which was proportional to acrylamide concentration. The calibration curve showed good linearity in the range of 200–800 ng mL?1 of acrylamide with a regression coefficient of 0.9989. The limit of detection of the method was 3.52 ng mL?1, and the relative standard deviations for concentrations of 300 ng mL?1 and 700 ng mL?1 were 99.8% × 10?2 and 79.7% × 10?2, respectively. 相似文献