novel spectrofluorimetric flow injection analysis (FIA) method was developed for the selective quantification of ascorbic acid via fluorescence quenching of serotonin hydrochloride. The system employs a custom-designed photometric array comprising 16 irradiation sources arranged in a dual-axis matrix—eight aligned horizontally and eight orthogonally, enabling multi-angle excitation and enhanced spectral resolution. Fluorescence signals were captured using a twin-pair solar cell detector, offering high sensitivity and minimal optical interference. The method exhibited a linear calibration range of 0.1–30 limit of detection (LOD) of 0.025 μ μ g/mL with a correlation coefficient (r mol /L, equivalent to 4.403 * 10 4 μ 2 ) of 0.9966, a g/mL per sample (0.1 mL (and limit of quantitative (LOQ) of 99.381 * 10 3 μ g/ml. Precision and accuracy were confirmed through intra- and inter-day validation, yielding relative standard deviations (RSD) below 2% and recovery rates exceeding 99%. Statistical comparison with conventional fluorometric techniques using a paired t-test revealed no significant difference at the 95% confidence level (p > 0.05), affirming the method's reliability. The proposed system supports high- throughput analysis of up to 50 samples per hour, with reduced reagent consumption and minimal environmental impact. Its robustness, cost-efficiency, and analytical performance render it a promising tool for routine pharmaceutical quality control and environmental monitoring
The present work is devoted to investigate the performance of a homemade Y-shape catalytic microreactor for degradation of dibenzothiophene (DBT), as a model of sulphur compounds including in gas oil, utilizing solar incident energy. The microchannel was coated with TiO2 nanoparticles which were used as a photocatalyst. Performance of the microreactor was investigated using different conditions (e.g., DBT concentration, LHSV, operating temperature, and (H2O2/DBT) ratio). Our experiments show that, in the absence of UV light, no reaction takes place. The results revealed that outlet concentration of DBT decreases as the mean residence time in the microreactor increases. Also, it was noted that operating temperature s
... Show MoreThis paper is concerned with the oscillation of all solutions of the n-th order delay differential equation . The necessary and sufficient conditions for oscillatory solutions are obtained and other conditions for nonoscillatory solution to converge to zero are established.
Metoclopramide (MCP) ion selective electrodes based on metoclopramide-phosphotungstic acid (MCP-PT) ion pair complex in PVC matrix membrane were constructed. The plasticizers used were tri-butyl phosphate (TBP), di-octyl phenyl phosphonate (DOPP), di-butyl phthalate (DBPH), di-octyl phthalate (DOP), di-butyl phosphate (DBP), bis 2-ethyl hexyl phosphate (BEHP). The sensors based on TBP, DOPP, DBPH and DOP display a fast, stable and linear response with slopes 59.9, 57.7, 57.4, 55.3 mV/decade respectively at pH ranged 2-6. The linear concentration range between 1.0×10-5 – 1.0×10-2 M with detection limit 3.0×10-6 and 4.0×10-6 M for electrodes using TBP, DOPP and DBPH while e
... Show MoreDicephalus parapagus twinning (DPT) is the rarest conjoined twinning entity of all conjoined twins. The presence of DPT is always associated with mortality before or after delivery. Antenatal diagnosis is crucial for planning labor, assembling a team, and providing counseling. Case presentation: A 23-year-old patient (G2P1A0) at 21 weeks of pregnancy attended the ultrasound clinic for routine care. A monoamniotic-monochorionic pregnancy was observed; the twin fetuses had two heads but one body, which corresponded to dicephalus parapagus twinning. A detailed ultrasound and fetal echocardiography reveal one heart without congenital anomalies. The liver, kidneys, and bladder appeared to be normally developed. Fetal MRI and karyotyping wer
... Show MoreZnIn2(Se1-xTex)4 (ZIST) chalcopyrite semiconductor thin films at various contents (x = 0.0, 0.2, and 0.4) are deposited on glass and p type silicon (111) substrate to produce heterojunction solar cell by using the thermal evaporation technique at RT where the thickness of 500 nm with a vacuum of 1×10-5 mbar and a deposited rates of 5.1 nm/s. This study focuses on how differing x content effect on the factors affecting the solar cell characteristics of ZIST thin film and n-ZIST/p-Si heterojunction. X-ray diffraction XRD investigation shows that this structure of ZIST film is polycrystalline and tetragonal, with (112) preferred orientation at 2θ ≈ 27.01. Moreover, atomic force microscopy AFM is studying the external morphology of
... Show MoreThe present work investigates the effect of magneto – hydrodynamic (MHD) laminar natural convection flow on a vertical cylinder in presence of heat generation and radiation. The governing equations which used are Continuity, Momentum and Energy equations. These equations are transformed to dimensionless equations using Vorticity-Stream Function method and the resulting nonlinear system
of partial differential equations are then solved numerically using finite difference approximation. A thermal boundary condition of a constant wall temperature is considered. A computer program (Fortran 90) was built to calculate the rate of heat transfer in terms of local Nusselt number, total mean Nusselt number, velocity distribution as well as te
To asses methylene blue as a cell marker, the cells of the buffy coat were labelled by incubating them in a medium containing a lable [Methylene blue] which is prepared in a concentration of 1%[1, 2, 3, 4, 5, 6] drops were tried at different periods of incubation [+/-,+/-, 1+/-, 1+/-] at 37 C degree. The results showed that monocytes and polymorphs are the main cells involved in the phagocytosis of this dye