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101.
102.
Sauleh Siddiqui Steven A Gabriel Shapour Azarm 《The Journal of the Operational Research Society》2015,66(4):664-673
Uncertainty and integer variables often exist together in economics and engineering design problems. The goal of robust optimization problems is to find an optimal solution that has acceptable sensitivity with respect to uncertain factors. Including integer variables with or without uncertainty can lead to formulations that are computationally expensive to solve. Previous approaches for robust optimization problems under interval uncertainty involve nested optimization or are not applicable to mixed-integer problems where the objective or constraint functions are neither quadratic, nor linear. The overall objective in this paper is to present an efficient robust optimization method that does not contain nested optimization and is applicable to mixed-integer problems with quasiconvex constraints (? type) and convex objective funtion. The proposed method is applied to a variety of numerical examples to test its applicability and numerical evidence is provided for convergence in general as well as some theoretical results for problems with linear constraints. 相似文献
103.
Siddiqui Madiha M. Nagargoje Amol A. Akolkar Satish V. Sangshetti Jaiprakash N. Khedkar Vijay M. Pisal Parshuram M. Shingate Bapurao B. 《Research on Chemical Intermediates》2022,48(3):1199-1225
Research on Chemical Intermediates - A simple and efficient protocol has been developed for the synthesis of new1,2,3-triazole-2,3-dihydroquinazolin-4[1H]-one (DHQ) conjugates(6a?j) via... 相似文献
104.
Amna Jabbar Siddiqui Caroline Le Snchal Sbastien Vilain Corinne Bur 《Journal of mass spectrometry : JMS》2020,55(10)
Lipid A is a major compound of the outer membrane of gram‐negative bacteria and is a key factor of bacterial virulence. As lipid A's structure differs among bacterial species and varies between strains of the same species, knowing its modifications is essential to understand its implications in the infectious process. To analyze these lipids, matrix‐assisted laser desorption ionization‐mass spectrometry (MALDI‐MS) is a well‐suited method that is fast and efficient. However, there are limitations with the matrix and additives used, such as the suppression of signal or prompt fragmentations that could give a false overview of lipid A composition in biological samples. For a comprehensive analysis of the entire lipid A species present in a sample, we tested 16 matrices and 11 additives on two commercial lipids A. The first commercial one contains single phosphorylation group, and the second contains two phosphorylation and two ketodeoxyoctonic acid (KDO) groups. The lipid A containing KDO groups was essentially detected by the 3‐hydroxypicolinic acid (3‐HPA) matrix, whereas the monophosphorylated lipid A could be detected by 13 matrices out of the 16. We also demonstrated that the signal of diphosphorylated lipid A can be enhanced with the use of additives in the matrix. Our study indicated that the best conditions to obtain a clear signal of both lipids A without prompt fragmentation was the use of 3‐HPA with 10mM trifluoroacetic acid (TFA). 相似文献
105.
Siddiqui Abuzar Abid Chamkha Ali J. 《Journal of Thermal Analysis and Calorimetry》2020,142(3):1345-1360
Journal of Thermal Analysis and Calorimetry - The steady flow of a nanofluid (mixture of titanium dioxide and water) in a rectangular channel under the influence of an inclined magnetic field is... 相似文献
106.
Qamar Uddin Ahmed Abdul Hasib Mohd Ali Sayeed Mukhtar Meshari A. Alsharif Humaira Parveen Awis Sukarni Mohmad Sabere Mohamed Sufian Mohd. Nawi Alfi Khatib Mohammad Jamshed Siddiqui Abdulrashid Umar Alhassan Muhammad Alhassan 《Molecules (Basel, Switzerland)》2020,25(23)
In recent years, there is emerging evidence that isoflavonoids, either dietary or obtained from traditional medicinal plants, could play an important role as a supplementary drug in the management of type 2 diabetes mellitus (T2DM) due to their reported pronounced biological effects in relation to multiple metabolic factors associated with diabetes. Hence, in this regard, we have comprehensively reviewed the potential biological effects of isoflavonoids, particularly biochanin A, genistein, daidzein, glycitein, and formononetin on metabolic disorders and long-term complications induced by T2DM in order to understand whether they can be future candidates as a safe antidiabetic agent. Based on in-depth in vitro and in vivo studies evaluations, isoflavonoids have been found to activate gene expression through the stimulation of peroxisome proliferator-activated receptors (PPARs) (α, γ), modulate carbohydrate metabolism, regulate hyperglycemia, induce dyslipidemia, lessen insulin resistance, and modify adipocyte differentiation and tissue metabolism. Moreover, these natural compounds have also been found to attenuate oxidative stress through the oxidative signaling process and inflammatory mechanism. Hence, isoflavonoids have been envisioned to be able to prevent and slow down the progression of long-term diabetes complications including cardiovascular disease, nephropathy, neuropathy, and retinopathy. Further thoroughgoing investigations in human clinical studies are strongly recommended to obtain the optimum and specific dose and regimen required for supplementation with isoflavonoids and derivatives in diabetic patients. 相似文献
107.
108.
T. Hayat Y. Wang A. M. Siddiqui S. Asghar 《Mathematical Methods in the Applied Sciences》2004,27(12):1447-1468
This paper is concerned with a mathematical hydrodynamical model of motility involving an undulating cell surface. The cell surface transmits stresses through a layer of exuded slime to the substratum. The slime is considered as a Johnson–Segalman fluid. A perturbation approach is used to find the analytic solution. Analytical expressions for the stream function, velocity, pressure gradient and pressure rise over a wavelength as well as the corresponding computational results are presented. The propulsive and lift forces and the power required for gliding propulsion have also been determined. The presented mechanism is found to generate a force for the propulsion of glider at a realistic speed and requires an output of power that is much less than the organism's metabolic rate of energy production. It is observed that unlike the Newtonian case of slime, the lift force is generated due to the Weissenberg number for non‐Newtonian slime, represented by the model of Johnson–Segalman fluid. It is also found that power required for translation in Johnson–Segalman fluid is reduced. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
109.
Hydrotreating of light cycle oil over CoMo/Al2O3, NiMo/Al2O3 and NiW/Al2O3 catalysts has shown that the type of catalyst has a critical influence on the composition and properties of the product.
Divergent effects of aromatics content and molecular weight on the cetane index by these catalysts occurred. Data show that
it was not possible to obtain a diesel product that meets stringent specifications using one type of catalyst in a single-stage
reactor even under severe operating conditions. 相似文献
110.
Thermal analysis of crude oils and comparison with SIMDIST and TBP distillation data 总被引:1,自引:0,他引:1
M. A. Ali M. A. B. Siddiqui S. M. J. Zaidi 《Journal of Thermal Analysis and Calorimetry》1998,51(1):307-319
Four commercial Saudi Arabian crude oils were characterized by thermogravimetry (TG) and differential thermal analysis (DTA).
These crude oils, Arab Berri (AB), Arab Light (AL), Arab Medium (AM) and Arab Heavy (AH), were also subjected to the traditionally
employed true boiling point (TBP) distillation and simulated distillation (SIMDIST). The TG/DTA data show that the hydrocarbons
present in these crude oils fall into four groups: the volatiles, the low molecular weight, the medium molecular weight and
the high molecular weight compounds. These four types of hydrocarbons were observed to display certain trends, such that the
volatile and low molecular weight hydrocarbons increased, while the medium and high molecular weight hydrocarbons decreased
with the lightness of the crude. The volatile contents of AB, AL, AM and AH crude oils up to 280°C were 50.1, 42.2, 42.3 and
38.5 mass percent, respectively. This confirms that AB is the lightest of these crude oils with maximum volatile content.
The mass percentage loss from the TG results is in good agreement with the percentage distilled from TBP (ASTM D 2892) and
SIMDIST. During evaporation, the TG mass loss follows a similar trend to those of the TBP and SIMDIST results and thus behaves
like distillation. During the oxidative degradation, the TG curve shows a higher mass loss as compared to the distillation
data. The higher deviation of the TG mass loss and percentage distilled at the higher-temperature end of the curve may be
attributed to the higher content of asphaltenes and carbonaceous material present in AH as compared to the AB crude oil. At
around 200°C, the TG mass loss curve intersects the TBP and SIMDIST curves and shows a derivation from distillation behaviour.
This intersection temperature of the TG and distillation curves is observed to decrease with the heaviness of the crude and
can be an indication of the onset of thermal degradation of hydrocarbons present in the crude oil. On the whole, the TG data
closely resemble the distillation results. 相似文献