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Asensitive and selective method employing chemiluminescence(CL) coupled with flow injection(FI) is reported for nalbuphine hydrochloride(NAL) assay in pharmaceutical formulations. The enhancement effect of NAL on the CL reaction between tris(2,2'-bipyridyl)ruthenium(II) chloride-diperiodatocuprate(III) {Ru[(bpy)3]2+-Cu(III) complex} in acidic medium is used as analytical measurement. The optimal conditions of the CL reaction were sulfuric acid 1.0×10-3 mol/L, Ru[(bpy)3]2+ 7.5×10-5 mol/L, Cu(III)/Ag(III) complexes 4.0×10-4/5.0×10-4 mol/L, sample loop volume of 120 μL and flow rate of 2.5 mL/min. The sensitivities of the method in terms of detection(S/N=3) and quantification(S/N=10) limits are 5×10-4 and 0.001 ppm(1 ppm=1 mg/L), respectively. The linear response of the instrument in the form of CL intensity with respect to NAL concentration is over the range 0.001-15.0 ppm(R2=0.9999) with relative standard deviation from 0.8% to 3.2% and injection throughput of 120 injection/h. The applications of the method include the quantitative analysis of NAL in pharmaceutical injection samples. Variations and the average results of the proposed method are not signi-ficantly different from the results of a reported method by applying F- and paired student t-test. The most likely CL reaction mechanism is written in accordance with spectrophotometric and CL studies.  相似文献   
2.
Within the framework of the radially constrained spherical Hartree–Fock (CSHF) approximation, the resonance effects of delta on the properties of neutron-rich double magic spherical nucleus 132Sn were studied. It was found that most of the increase in the nuclear energy generated under compression was used to create massive Δ particles. For 132Sn nucleus under compression at 3.19 times density of the normal nuclear density, the excited nucleons to Δs were increased sharply up to 16% of the total number of constituents. This result is consistent with the values extracted from relativistic heavy-ion collisions. The single particle energy levels were calculated and their behaviours under compression were examined. A meaningful agreement was obtained between the results with effective Hamiltonian and that with the phenomenological shell model for the low-lying single-particle spectra. The results suggest considerable reduction in compressibility for the nucleus, and softening of the equation of state with the inclusion of Δs in the nuclear dynamics.  相似文献   
3.
We consider a heat equation in one dimension with a boundaryinput and distributed output. An approximate inverse for theinput—output system described by this model is developed.The inverse is obtained by Galerkin approximation either (1)before or (2) after inversion. An estimate of the error dueto the approximation is established for the two cases. In addition,Fourier-series expansion is used to compare these inversionmethods.  相似文献   
4.
The decision to marry is one of the most critical decisions in young ladie' lives where wrong choices may have adverse effects. This study investigates this issue in developing countries using the small state of Kuwait as a manageable case study. This research utilizes the analytical hierarchy process (AHP) due to the multiplicity of objectives. Women from different ethnic, religious, and residential backgrounds were surveyed. The problem considers eight criteria and four alternatives (male candidates). It was found from the study that the most preferred criteria are personality, followed by marital status and religious status, respectively.  相似文献   
5.
MOHAMMED A MINSHED 《Pramana》2013,80(3):487-505
There is a strong need for the optimized management of the thermal problem in Nd:YAG laser rod and for a powerful, fast, and accurate modelling tool capable of treating the heat source distribution very close to what it actually is. In this paper, a new optimization algorithm called bacterial foraging optimization algorithm (BFOA) is proposed for simulation of the radial heat distribution. A BFOA discloses a simulation method which delivers the exact temperature distribution in a circularly cylindrical structure with a circularly symmetrical, longitudinally, and transversally non-uniform heat source distribution and circularly symmetrical cooling means. The output power is obtained and compared with previously published experimental measurements for different pump power and a good agreement has been found.  相似文献   
6.
A novel chemiluminescence(CL) method is proposed for cefixime trihydrate(CFX) determination based on its eiiliancement effect on diperiodatoargentate(III)(DPA)-rhodamine 6-G(Rh6-G) reaction in conjunction with flow injection analysis(FIA). A linear calibration curve was achieved over the range from 0.01 mg/L to 2.5 mg/L CFX(R^2=0.999,n=8) with relative standard deviation(RSD) of 1.4%-3.8%(n=4)), limit of detection(LOD) of 3.0×10^-3 mg/L(S/N=3),injection tliroughput of 180/h and regression equation of y=1113.2x-14.596[y=CL intensity (mV) and x=concentration of CFX(mg/L)]. The method was successfully applied to CFX determination in pharmaceutical formulations and the recoveries(%) for proposed FI-CL and a reported spectrophotometric method by applying the Student t-test [calculated t-test value: t=1.079215, and tabulated t-distributed(95%)=2.200985] were not significantly diflerent. The CFX was efficiently extracted and no significant effect of commonly found excipients in the pharmaceutical formulations was observed. The mechanism of CL reaction is discussed briefly.  相似文献   
7.
The main goal of this paper is to approximate the Kuramoto-Shivashinsky (K-S for short) equation on an unbounded domain near a change of bifurcation, where a band of dominant pattern is changing stability. This leads to a slow modulation of the dominant pattern. Here we consider PDEs with quadratic nonlinearities and derive rigorously the modulation equation, which is called the Ginzburg-Landau (G-L for short) equation, for the amplitudes of the dominating modes.  相似文献   
8.
We present here a mathematical explanation of how the Schr?dinger equation for a class of harmonic oscillators possesses exact solutions. Some of the extended potentials used here are not present in the literature.  相似文献   
9.
ABSTRACT. Murray Basin water resources are under increasing pressure to satisfy often conflicting environmental and economic objectives. Governments, as the “environmental steward,” have several management options including water trading and banking water until it can be used to greatest effect and occasionally selling water back to irrigators. This is sometimes known as counter‐cyclic trading. To examine the potential of the above options, a model of water trading and banking in a simple market is developed. The model combines a catchment hydrology model with economic information that drives land use practice and demand for water. Simulations are used to explore these options at a strategic level. The potential impacts of increased upland afforestation and climate change on catchment hydrology in the presence of a pro‐active environmental steward are considered. It is concluded that in a system where entitlements are capped it is likely that the most cost‐effective management system will involve counter‐cyclic trading.  相似文献   
10.
We study the Hopf *-algebra structures on the Hopf algebra H(1, q) over ?. It is shown that H(1, q) is a Hopf *-algebra if and only if |q| = 1 or q is a real number. Then the Hopf *-algebra structures on H(1, q) are classified up to the equivalence of Hopf *-algebra structures.  相似文献   
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