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Detection and identification of chemical warfare agents and their precursors/reaction products in various environmental matrices are important tasks which are considered in chemical weapons convention (CWC). 2-[(2-chloroethyl)(alkyl)amino]ethyl alkyl methylphosphonates I and N-alkyl bis(2-(alkoxy-methylphosphoryloxy)amines II are covered under schedule 2.B.4 of CWC and have structures closely related to the nerve and blister agents. In fact, they are products of the reactions between these two different CWC scheduled compounds: nerve agents and nitrogen mustards. Ion fragmentations during mass spectrometry studies of these chemicals were investigated using electron ionization mass spectrometry. Structures of fragments were confirmed using EI-MS analysis of the deuterated analogs. Density functional theory was also used to show preferred fragmentation pathways. Mass spectrometric studies revealed some fragmentation pathways, such as, McLafferty-type and hydrogen rearrangements and elimination of chlorine, chloromethylene radical, alkene and HCl.

A new and one-pot synthesis of oxazolines has been accomplished by K5[PW11ZnO39].23H2O—catalyst acylation followed by C–N ring opening/C–O bond formation in NH ketoaziridines. This regio- and stereo-selective reaction presumably proceeds via a domino sequence resulting in the in situ generation of acyl aziridine which undergoes a ring expansion reaction via an initial C–N rupture of aziridine ring followed by ring closure to the oxazolines. The methodology provided novel one-pot procedure for the synthesis of trans-2,5-diaryl-4-aroyloxazolines.

It is known that metalation of (RMe2Si)3CH (R: a = Me, b = Ph) with MeLi in THF yields (RMe2Si)3CLi, which when reacted with allyl bromide, (RMe2Si)3C-CH2-CH=CH2 (1a, 1b) are produced. In this study, although (PhMe2Si)3CLi does not react with benzyl bromide, under the same conditions (Me3Si)3CLi does, giving the expected product. We found that the bromination of 1b was unsuccessful and the reaction of 1a occurs in low yield due to severe steric hindrance. This idea is supported by our results, which show that, when treated with dichlorocarbene and dibromocarbene, 1a and 1b yield the related dihalocyclopropanes. Furthermore, reduction of the obtained products gives the dehalogenated compounds.

By the self-assemble reaction of tri(2-carboxyethyl)isocyanurate (H3tci) and Ni(NO3)2·6H2O under solvothermal conditions, a new Ni(II) compound has been successfully prepared and structurally characterized, and its chemical formula is [Ni5(μ3-OH)2(NO3)2(tci)2(DMA)4]n (1). The optical band gap (Eg) of 1 is 3.4 eV, which makes it exhibit photocatalytic effect for the MB degradation under the irradiation of ultraviolet light with 88.41% MB successful removal within 120 min. Its application values on the acute ischemic myocardial infarction were assessed and its detailed mechanism was also investigated. Firstly, the inflammatory cytokines levels were released into the plasma during acute myocardial infarction after treated with the ELISA detection kit. Moreover, the real-time RT-PCR assay was carried out for the measurement of the lncRNA-ZFAS1 relative expression levels. Above all, we can get the conclusion that the compound possesses excellent application value on the ischemic myocardial infarction treatment through regulating expression level of lncRNA-ZFAS1.

Novel solid-phase microextraction coatings were prepared using cathodic and anodic plasma electrolytic deposition and used to measure the content of nerolidol in water and water distillate of bitter orange blossoms with GC-FID. The morphology of the prepared coatings was examined by field emission scanning electron microscopy. Effective parameters in the extraction and desorption were investigated. The optimal conditions include microextraction of 50 mL of an aqueous solution containing 35% (w/v) NaCl at 45 °C for 45 min using anodic coating, followed by desorption using 50 μL hexane in an ultrasonic bath for 5 min. The developed method has a linear dynamic range of 1–1000 ng mL−1 (R2 = 0.9980). The limit of detection (S/N = 3) and the limit of quantification (S/N = 10) of the developed method were 0.3 and 1 ng mL−1, respectively. The intra-, inter-day, and fiber-to-fiber relative standard deviations were 8–16, 9.2–16.7 and 10.1–13.0%, respectively. The concentration of the water distillate of bitter orange blossom was measured as 250 ng mL−1. The prepared adsorbent can be used many times due to its good mechanical stability. The developed method was used for the determination of nerolidol, as a product quality indicator, in the water distillate of bitter orange blossom. The developed method is simple, convenient, sensitive and with acceptable reproducibility that can be used for the microextraction of volatile organic compounds in various aqueous and food matrices.

A novel compound (1E,1′E)-N,N′-(ethane-1,2-diyl)bis(1-(5-nitrothiophen-2-yl)methanimine) [EDNM] was synthesized from thiophene derivative in view to get multidentate ligand with potential biological activity. EDNM is characterized by FT-IR, 1H and 13C NMR and UV–Vis spectroscopic techniques and confirmed by SCXRD. EDNM crystallizes in the monoclinic system with P21/c space group with Z value 4 and unit cell parameters a = 5.6540(3) Å, b = 17.9249(8) Å and c = 7.5077(5) Å. DFT was employed for theoretical evaluations using B3LYP with the basis set 6–311 +  + G (d,p). Geometry optimization, vibrational analysis, NMR, electronic absorption, MEP, FMO, Mulliken charges and NBO analysis were performed, thereby establishing the nature of reactive sites, band energy gap and atomic charges of EDNM. Theoretical values matched well with the experimental findings. NBO analysis revealed the donor acceptor interactions in molecule. Analysis of global reactivity descriptors along with Fukui indices outlines the elaborate scheme of reactive sites of the molecule, and Hirshfeld surface investigation revealed the intermolecular interactions in crystal packing.

A nanohybrid of Pt nanoparticles and reduced graphene oxide (Pt/rGO) is prepared and exploited for hydrogen evolution reaction (HER) in acidic medium. At first, glassy carbon electrode (GCE) is modified by graphene oxide (GO) nanosheets. Then, during the electrochemical reduction, GO film is converted to rGO. Finally, rGO/GCE is immersed in acidic solution of mM K2PtCl6 for 20 min and then with scanning the potential of electrode from 0.00 to − 0.20 V vs. NHE, Pt (IV) ions are reduced to Pt. Characterization of Pt/rGO nanohybrid is achieved by field emission scanning electron microscopy (FESEM) and energy dispersive spectroscopy. FESEM images confirm that on the surface of rGO film, Pt nanoparticles with size in the range of 5–15 nm are formed. Electrochemical experiments reveal that Pt/RGO/GCE exhibits a small onset potential of − 0.03 V vs. NHE and Tafel slope of about 33 mV dec− 1 for HER. Pt/rGO/GCE has higher electrocatalytic activity for HER than rGO/GCE and Pt/GCE. In addition, the nanohybrid presents an enhanced catalytic activity towards HER than bare Pt electrode. It is observed that the current density of HER at the Pt/rGO nanohybrid shows a little decrease after 1000 continuous potential cycles which means the good stability of the catalyst. In addition, chronoamperometric studies show that Pt/rGO/GCE exhibits a noticeable stability for HER. The obtained results allege that Pt/rGO nanohybrid can surmount the overvoltage of HER and can be used as promising electrocatalyst in HER in acidic medium.

This work concerns the development of a novel and rapid in situ dispersive liquid–liquid microextraction method for magnetic retrieval of ionic liquid as a new approach for the separation of benzophenone type (BP-type) UV filters via quantification using UPLC with PDA detection. The analytes determined in this study were a group of three benzophenones: 2,4-dihydroxybenzophenone (BP1), 2,2′,4,4′-tetrahydroxybenzophenone (BP2) and 2-hydroxy-4-metoxybenzophenone (BP3). The hydrophilic ionic liquid found suitable for use as an extraction solvent of the targeted analytes was didecyldimethylammonium chlorate (DDAC). An anion exchanger, NaClO4 was added to promote a metathesis reaction and in situ formed the IL, [DDA][ClO4]. The experimental parameters such as the concentration of IL, the molar ratio of DDAC to NaClO4, amount of iron oxide added and volume of water sample were investigated and optimised using a step-by-step optimisation process. The optimum experimental parameters were as follows: 30 mL of sample volume, 1% concentration of DDAC, the molar ratio of DDAC to NaClO4—1:2, and 5 mg of Fe3O4 magnetic nanoparticles. The proposed extraction method is simple and requires no more than 5 min. The detection limit (LOD) obtained for target analytes ranged from 12.320.0 ng L−1, while the correlation coefficient (r2) was from 0.9995 to 0.9999. Finally, the developed method was successfully applied to the determination of BP-type UV filters in environmental water samples, and satisfactory results were obtained.

A simple and rapid method was developed for clinical naked-eye and quantitative detection of paraquat (PQ) in human plasma and urine samples using built-in-house analytical devices followed by visual colorimetric method and UV–Vis spectrophotometry. A quantitative spectrophotometric method for PQ was also developed based on device built in-house. Different factors influencing the recovery efficiency of PQ such as the pH of the sample solution, the amount of adsorbent, the type and volume of eluent, the extraction and desorption time, the adsorption capacity and sample volume were studied and optimized in detail. Under optimal conditions, the whole analysis time of the naked-eye method was less than 5 min and it provided the detection limit observed with naked eye of 0.2 μg/mL with the detection range between 0.5 and 5.0 μg/mL for paraquat determination. PQ could be detected as low as 6.21 × 10−3 μg/mL in urine and 0.119 μg/mL in plasma with this proposed quantitative spectrophotometric method, respectively. The method was applied in monitoring PQ levels in plasma and urine at different hemoperfusion numbers in local hospitals for patients exposed to PQ poisoning. The detection result could not only enable immediate medical intervention but also benefit patients’ survival.

In this regard, a new sensitive electrochemical sensor has been introduced for direct detection of cholesterol (CHL). The proposed sensor was manufactured by modifying the pencil graphite electrode (PGE) with copper nanoparticles (CuNPs) and indole (IND). The chemical modifiers of CuNPs and IND were easily deposited on PGE via electrodeposition procedure. The designed sensor exhibited a desired catalytic response to CHL with the archived parameters of α = 0.62, log Ks = 3.42 and Γ = 2. 74 × 10–8 in the optimized pH of 7. The morphology of the constructed films was characterized by scanning electron microscopy technique. For this sensor, a linear calibration curve is plotted within the range of 15–195 nmolL−1, and the limit of detection was achieved 4.98 nmolL−1. Furthermore, the offered sensor was employed to direct measuring of CHL in human serums, and the acceptable accuracies were acquired for this method without any side interferences.