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91.
A flow injection spectrophotometric method is proposed for the determination of bromoxynil herbicide. Bromoxynil was hydrolyzed with HCl and the resulting product, 3,5-dibromo-4-hydroxyaniline, was diazotized with nitrite and coupled with aniline. The absorbance of the azo dye was measured at 500 nm. The conditions were optimized for diazotization using FIA. The range of linearity was found to be 0.01 to 5 ppm with a molar absorptivity of 1.27 x 10(5) L mol(-1) cm(-1). The % recovery for the determination of bromoxynil was found to be 91%. The sampling frequency was 80 samples per hour for FIA. The method is simple, fast, and has been successfully applied to the determination of bromoxynil in commercial formulations and food samples. 相似文献
92.
I. O. Abugassa S. O. Abugassa Y. S. Khrbish A. T. Bashir K. Doubali N. Ben Faid 《Journal of Radioanalytical and Nuclear Chemistry》2006,269(3):643-646
Summary The trace elements composition of gallbladder stones samples of the types cholesterol, pigment and mixed stones in addition
to bile have been investigated by k0-instrumental neutron activation analysis (k0-INAA). The samples were obtained from several individuals of adult subjects of the Libyan population who undergone open surgery
of gallbladder (cholecystectomy) at Al-khadra University Hospital in Tripoli. The samples were lyophilized, irradiated together
with Au wire and Zr foil, which serve as flux ratio monitor and a parameter at TNRC. Concentrations of 24 elements in gallstone
and 23 elements in bile were determined. The levels of the trace elements in the various samples investigated are measured
and discussed. The reliability of the analysis was checked with several biological standard reference materials. 相似文献
93.
Fiona Byrne Adriele Prina-Mello Bashir M. Mohamed Yurii K. Gun’ko Yuri Volkov 《Journal of magnetism and magnetic materials》2009,321(10):1341-1345
Nickel nanowires, 20 μm long and 200 nm in diameter, were fabricated by electrodeposition into alumina templates, and characterised by superconducting quantum interference device (SQUID) magnetometer, X-ray diffraction and scanning electron microscopy. Biocompatibility studies of nickel nanowires with differentiated THP-1 cell line-derived macrophages were carried out. From a multiparametric assay, using high content analysis (HCA), the critical time points and concentrations of nickel nanowires on THP-1 cellular response were identified. The nanowires displayed little or no toxic effects on THP-1 cells over short incubation times (10 h), and at low concentrations (<100 nanowires per cell). Our findings indicate the potential suitability of these wires for biological and clinical applications. 相似文献
94.
95.
96.
S. Bashir R. W. McCabe C. Boxall M. S. Leaver D. Mobbs 《Journal of nanoparticle research》2009,11(3):701-706
Forced hydrolysis of Fe(III) ions in acidic media was performed under controlled synthetic conditions to produce α- and β-FeOOH
iron oxides. The forced hydrolysis synthesis was carried out, separately, in an aqueous medium and the lamellar lyotropic
liquid crystalline phase of a commercial non-ionic surfactant/water system. The FT-IR analyses confirmed formation of α- and
β-FeOOH iron oxides in the aqueous and the surfactant media with slight formation of ferrihydrite and haematite. TEM micrographs
have shown that particles formed in the lamellar lyotropic phase are smaller than those produced in the aqueous medium with
their smallest size dimension being constrained in the nanometre scale with a size ranging between 5 and 100 nm. Particles
produced in the nanoscale size appeared to have different optical properties compared to their counterparts produced in the
microscale size. 相似文献
97.
98.
In this paper, we study the dynamics of a stochastic Susceptible-Infective-Removed-Infective (SIRI) epidemic model with relapse. By constructing a suitable stochastic Lyapunov function, we establish sufficient conditions for the existence of an ergodic stationary distribution to the model. Moreover, sufficient conditions for extinction of the disease are also obtained. 相似文献
99.
Abstract A class of non-mesogenic molecules, which as mixtures exhibit monotropic nematic phases, is described. 相似文献
100.
A new homologous series of thermotropic liquid crystalline poly (azomethine‐ether)s based on dibenzylidene derivatives were synthesized by solution polycondensation of various diformyl‐α,ω-diphenoxyalkanes, I–VIII with 2,6‐bis(m‐aminobenzylidene)‐4‐phenylcyclohexanone X, and characterized by 1H‐NMR, IR and elemental analyses. The inherent viscosities of the polymers were in the range 0.29–0.58 dI/g. All the poly (azomethine‐ether)s were insoluble in common organic solvents but dissolved completely in concentrated H2SO4 and methanesulphonic acid. The mesomorphic properties were studied as a function of the diphenoxyalkane space length. Analysis by DSC and optical polarized microscopy demonstrated that the poly (azomethine‐ether)s from nematic mesophases over wide temperature ranges. 相似文献