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61.
This paper presents an experimental and theoretical investigation of drying of moist slab, cylinder and spherical products
to study dimensionless moisture content distributions and their comparisons. Experimental study includes the measurement of
the moisture content distributions of slab and cylindrical carrot, slab and cylindrical pumpkin and spherical blueberry during
drying at various temperatures (e.g., 30, 40, 50 and 60°C) at specific constant velocity (U = 1 m/s) and the relative humidity φ = 30%. In theoretical analysis, two moisture transfer models are used to determine drying process parameters (e.g., drying
coefficient and lag factor) and moisture transfer parameters (e.g., moisture diffusivity and moisture transfer coefficient),
and to calculate the dimensionless moisture content distributions. The calculated results are then compared with the experimental
moisture data. A considerably high agreement is obtained between the calculations and experimental measurements for the cases
considered. The effective diffusivity values were evaluated between 0.741 × 10−5 and 5.981 × 10−5 m2/h for slab products, 0.818 × 10−5 and 6.287 × 10−5 m2/h for cylindrical products and 1.213 × 10−7 and 7.589 × 10−7 m2/h spherical products using the Model-I and 0.316 × 10−5–5.072 × 10−5 m2/h for slab products, 0.580 × 10−5–9.587 × 10−5 m2/h for cylindrical products and 1.408 × 10−7–13.913 × 10−7 m2/h spherical products using the Model-II. 相似文献
62.
Halime Güzin Aslan Senem Akkoç Zülbiye Kökbudak Lütfiye Aydın 《Journal of the Iranian Chemical Society》2017,14(11):2263-2273
We presented the synthesis of a new Schiff base and its complexes properties with some transition metal ions in this study. (1-amino-2-thioxo-4-p-tolyl-1,2-dihydropyrimidin-5-yl)(p-tolyl)methanone was synthesized as the starting material, and (1-((2-hydroxynaphthalen-1-yl)methyleneamino)-2-thioxo-4-p-tolyl-1,2-dihydropyrimidin-5-yl)(p-tolyl)methanone (Hnafmmp) (1) and its Ni(II) (2), Pd(II) (3), Pt(II) (4), Cu(II) (5), Co(II) (6) complexes were prepared using above-mentioned starting material. The structures of these new compounds (ligand and its complexes) were characterized with UV–Vis, FTIR, LC–MS, 1H NMR, 13C NMR, magnetic susceptibility, conductivity measurement, X-ray powder diffraction method, and thermal analyses techniques. The 1H NMR chemical shifts of all complexes were calculated by using the gauge-invariant atomic orbital HF (3.21G) method in DMSO phases. All measured results were compared with the experimental data. The ligand and its complexes were also evaluated as antimicrobial agents against representative strains bacteria. Furthermore, we studied the catalytic activity of these compounds in Suzuki–Miyaura cross-coupling reaction in aqueous media. 相似文献
63.
Elif Burcu Aydın Muhammet Aydın Mustafa Kemal Sezgintürk 《Macromolecular bioscience》2023,23(1):2200390
An early on time detection of breast cancer significantly affects the treatment process and outcome. Herein, a new label-free impedimetric biosensor is developed to determine the lowest change in the level of calreticulin (CALR), which is a new biomarker of breast carcinoma. The proposed immunosensor is fabricated by using reduced graphene oxide/amino substituted polypyrrole polymer (rGO-PPyNH2) nanocomposite modified disposable electrode. The anti-CALR antibodies are first attached on the rGO-PPyNH2 nanocomposite coated electrode through glutaraldehyde crosslinking; the CALR antigens are then immobilized with the addition of CALR antigens to form an immunocomplex on the sensing surface. This immunocomplex induces considerably larger interfacial electron transport resistance (Rct). The variation in the Rct has a linear relationship with CALR level in the detection range of 0.025 to 75 pg mL−1, with a detection limit of 10.4 fg mL−1. The suggested biosensor shows high selectivity to CALR, good storage stability (at least 5 weeks) and suitable reproducibility results as shown in quality control chart. The designed immunosensor is utilized to analyze CALR levels in human sera with satisfying results. This immunosensor provides a novel way for the clinical determination of CALR and other cancer biological markers. 相似文献
64.
A rapid, simple, selective and sensitive method for the spectrophotometric determination of nitrite in water has been developed and optimum reaction conditions along with other analytical parameters have been evaluated. Nitrite reacts with barbituric acid in acidic solution to give the nitroso derivative, violuric acid. At analytical wavelength of 310 nm, Beer's law is obeyed over the concentration range 0.00–3.22 ppm of nitrite. The molar absorptivity is 15330 ± 259.7 (95%) with pooled standard deviation of 355.57 and R.S.D. of 2.32%. As well as the method is sensitive (2.99 × 10−3 μg NO2 cm−2) and selective, it tolerates most of the potential interferents. It has been successfully applied to nitrite determination in natural waters by use of a calibration graph with determination limit of 1.66 μg NO2 in 100 mL working solution corresponding to minimum 9.5 ppb NO2–N in water samples. Lower concentrations of nitrite (3.0 μg NO2/L sample) is precisely analyzed by using the method of dilution with sample, with R.S.D. of lower than 0.5%. The results were compared with standard N-(1-naphtyl)ethylenediamine dihydrochloride method and very good agreement between the data was observed. The method can easily be applied in the field. 相似文献
65.
2-Hydroxy-2,2-diphenylacetohydrazide (2), cyclic ketones, and mercaptoalkanoic acids were converted into 2-hydroxy-N-(3-oxo-1-thia-4-azaspiro[4.4]non/[4.5]dec-4-yl)-2,2-diphenylacetamide derivatives (3, 4) in a one pot procedure. Compounds 3 and 4 were tested for in vitro antimycobacterial activity against M. tuberculosis H37Rv. The compounds were found to provide 0–86% inhibition of mycobacterial growth in the primary screen conducted at 6.25 μg/cm3. 相似文献
66.
67.
We consider the Galerkin finite element method (FEM) for the incompressible magnetohydrodynamic (MHD) equations in two dimension. The domain is discretized into a set of regular triangular elements and the finite‐dimensional spaces employed consist of piecewise continuous linear interpolants enriched with the residual‐free bubble functions. To find the bubble part of the solution, a two‐level FEM with a stabilizing subgrid of a single node is described and its application to the MHD equations is displayed. Numerical approximations employing the proposed algorithm are presented for three benchmark problems including the MHD cavity flow and the MHD flow over a step. The results show that the proper choice of the subgrid node is crucial to get stable and accurate numerical approximations consistent with the physical configuration of the problem at a cheap computational cost. Furthermore, the approximate solutions obtained show the well‐known characteristics of the MHD flow. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
68.
Ali Aydın Selçuk 《Journal of Cryptology》2008,21(1):131-147
Despite their widespread usage in block cipher security, linear and differential cryptanalysis still lack a robust treatment
of their success probability, and the success chances of these attacks have commonly been estimated in a rather ad hoc fashion.
In this paper, we present an analytical calculation of the success probability of linear and differential cryptanalytic attacks.
The results apply to an extended sense of the term “success” where the correct key is found not necessarily as the highest-ranking
candidate but within a set of high-ranking candidates. Experimental results show that the analysis provides accurate results
in most cases, especially in linear cryptanalysis. In cases where the results are less accurate, as in certain cases of differential
cryptanalysis, the results are useful to provide approximate estimates of the success probability and the necessary plaintext
requirement. The analysis also reveals that the attacked key length in differential cryptanalysis is one of the factors that
affect the success probability directly besides the signal-to-noise ratio and the available plaintext amount. 相似文献
69.
Percentages of crude oil, protein, fibre and ash of grape seeds obtained from Turkish cultivars were of the ranges 5.40-10.79, 5.24-7.54, 17.6-27.1, and 1.2-2.6, respectively. The highest crude oil, crude protein and crude fibre were determined in Siyah pekmezlik, Karadimrit and Antep grape seeds. The energy values of seeds were established to be between 102.28 and 148.07?kcal?g(-1). Potassium and calcium contents of seed samples were found to be at high levels compared to sodium. The seeds contained 686-967?ppm of Na, 2468-3618?ppm of K and 2373-4127?ppm of Ca. The refractive index, relative density, acidity, saponification value, unsaponifiable matter and iodine value of seed oils were determined to be in the ranges 1.474-1.477 [Formula: see text], 0.909-0.934 25/25°C, 0.74-1.24%, 181-197, 0.91-1.66%, and 126-135, respectively. The main fatty acids were of the ranges 60.7-68.5% linoleic, 16.1-23.4% oleic and 8.0-10.2% palmitic. The highest percentages of linoleic acid (68.5%) was determined in Siyah pekmezlik seed oil. 相似文献
70.
Poly-2-[4-(diethylaminophenyl)imino]-5-nitro-phenol (PEAPINP) and 2-[4-(diethylaminophenyl)imino]-5-nitro-phenol (EAPINP)
were prepared as new pH sensors. Spectrophotometric and spectrofluorometric response of the novel sensors in various pH values were investigated. EAPINP has the ability to respond linearly at alkaline PH values, 8 to 9, and can be utilized in absorption and wavelength radiometric methods. PEAPINP has the ability to respond
linearly at lower pH values, 6 to 7, and can be used as an alternative pH sensor in this range. The new sensors are yellow-colored
in acidic and neutral media and red-colored in alkaline PHs. With their colorimetric responses at different pH ranges EAPINP and PEAPINP can be used to develop color-tunable PH sensors. 相似文献