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991.
In this work, a sensitive, practical and reliable acetylthiocholine (ATCh) biosensor based on poly(allylamine hydrochloride) functionalized multiwalled carbon nanotube (PAH/MWCNT) was fabricated and used for pesticide detection. As far as we know, this is the first work that constitutes the usage of PAH and MWCNT for ATCh biosensor. The developed system was characterized by using scanning electron microscopy, electrochemical impedance spectroscopy and cyclic voltammetry. The influence of parameters such as enzyme amount and pH were examined and a linearity between 5×10?5 M?2.0×10?3 M for ATCh was obtained. The proposed biosensor was applied for a model pesticide, monocrotophos, detection. The analytical curve showed an excellent linearity in the monocrotophos concentration range of 1–25 pg/mL with an incubation time of 5 min. Limit of detection and limit of quantification values were calculated as 0.88 and 2.9 pg/mL, respectively. The system was also applied for detection of monocrotophos in grape, tomatoe, tap and mineralized water samples and promising recovery values were obtained. 相似文献
992.
M. El-borai M. F. Abdel-megeed 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):165-173
Abstract The mass spectral fragmentation of thiophenotropone, thiophenotropilidene derivatives and their iron and chromium tricarbonyl complexes are fully reported and discussed. The fragmentation patterns of the complexes are characterised by successive loss of three carbonyl groups. In general, the resulting ions after elimination of the metal behave in the same manner as the organic ligand. The iron complexes behave differently from their corresponding chromium complexes. The thiopheno[b]tropilidene iron tricarbonyl complex and its isomer thiopheno[c]tropilidene iron tricarbonyl complex could not be differentiated by mass spectrometry, such differentiation was achieved by proton magnetic resonance. 相似文献
993.
Il'yas S. Nizamov Alexey E. Popovich Elvira S. Batyeva Nail M. Azancheev Vladimir A. Al'fonsov 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):167-178
Abstract The reactions of tetraphosphorus decasulfide and Lawesson's reagent with tetra-, tri- and dialkoxysilanes were studied. On the basis of these reactions, new S-silyl esters of phosphorus(V) thioacids have been prepared. The prepared compounds were identified by IR, 1H, and 31P NMR and mass spectra as well as elemental analyses. 相似文献
994.
H. Dhaouadi H. Marouani M. Rzaigui A. Madani 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1801-1814
Chemical preparation, crystal structure, thermogravimetric and differential analysis, solid state 31P MAS NMR characterization, and IR spectroscopic investigations are given for a new organic cation dihydrogenmonophosphate, (2-CH3OC6H4CH2NH3)H2PO4. This compound is monoclinic C2/c, with unit cell parameters a = 27.740(8), b = 4.827(2), c = 16.435(3) Å, β = 93.79(2)°, V = 2196 (1) Å3, Z = 8, and ρ = 1.422 g · cm?3. The crystal structure has been determined and refined to R = 0.046 (Rw = 0.056), using 1,746 independent reflections with I > 3σ (I). Its atomic arrangement can be described by infinite polyanions [H2PO4] n n ?, organized in ribbons alternating with organic cations. Strong hydrogen bonds connect the different components. Electrical conductivity measurements show that the [2-CH3OC6H4CH2NH3]H2PO4 has a low ionic conductivity value at 403 K. 相似文献
995.
Evgenyi V. Gryshkun Natalia V. Andrushko Oleg I. Kolodiazhnyi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1027-1046
Racemic chlorophosphines react stereoselectively with chiral l-phenylethylamines or amino acid esters to give diastereomerically enriched aminophosphines 3, which were isolated as diastereomerically pure crystalline borane complexes. Oxidation, thionation, the reaction with methyl iodide provide optically active derivatives of aminophosphines. (R,S)- and (S,S)-stereomers of phosphinic acid amides were separated by crystallization and a flash-chromatography. The stereochemical properties of phosphorus acid amides were investigated. The mechanism of asymmetric induction at the trivalent phosphorus atom was rationalized. 相似文献
996.
Il'yas S. Nizamov Elvira S. Batyeva Vladimir A. Al'fonsov Rashid Z. Musin Arkady N. Pudovik 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):229-237
Abstract The reactions of tetraphosphorus trisulfide with thioacetals, aminals, sulfenamides and disulfides were studied. The reactions were found to give organothiophosphorus compounds and to be facilitated by organic amines and benzoyl peroxide. 相似文献
997.
Werner Uhl 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4-5):743-748
Organogallium or-indium subhalides are easily available by the halogenation of the corresponding tetrahedral clusters E 4 [C(SiMe 3 ) 3 ] 4 . Three types of compounds are formed that retain the tetrahedral arrangement of In atoms or give chains with two or three Ga or In atoms connected by E─E bonds. These subhalides are suitable starting compounds for the synthesis of secondary products containing the elements in low oxidation states. Carboxylato derivatives or transition metal complexes were obtained on such a route. A persistent radical anion was formed on electron transfer to Ga 9 (CMe 3 ) 9 . 相似文献
998.
Anastasia O. Kolodiazhna Irina V. Guliaiko Oleg I. Kolodiazhnyi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2335-2346
Abstract The addition of silylphosphines to chiral aldehydes proceeds with high diastereoselectivity to give optically pure tertiary α -trimethylsiloxyalkylphosphines. The diastereomeric excesses of the addition products were achieved to 90–100%. The reaction of bis(trimethylsilyl)phenylphosphine with the acetonide of (R)-glyceraldehyde provides diastereomerically enriched tertiary bis(glyceryl)phosphines. 相似文献
999.
Sedat Ture Rafig Gurbanov Murat Tuna 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):600-610
AbstractThe reactions of hexachlorocyclotriphosphazatriene, N3P3Cl6 (1) with 2-mercaptoethanol, 2-HS-CH2-CH2-OH (2), in (1:1, 1:2 and 1:3) mole ratios, in excess of NaH, in THF and diethylether solutions yield a total of 6 novel products: one mono spiro, N3P3Cl4[O-CH2-CH2-S] (3); one mono-substituted open chain, N3P3Cl5[S-CH2-CH2-OH] (4); one dispiro, N3P3Cl2[O-CH2-CH2-S]2 (5); one tri-substituted open chain, N3P3Cl3[S-CH2-CH2-OH]3 (6); one tris-spiro, N3P3[O-CH2-CH2-S]3 (7) and one disubstituted open chain, N3P3Cl4[S-CH2-CH2-OH]2 (8) derivatives. The spiro products (3, 5 and 7) are formed as the major products in this system and all of the synthesized compounds are found to be stable at room temperature. The structures of the derived compounds were elucidated by elemental analysis, TLC-MS, 31P and 1H NMR spectral data. For evaluation of melting behavior of derivatives (6) and (7), thermal transition peaks and their corresponding enthalpies were determined via DSC technique. 相似文献
1000.