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21.
Peyman Yousefvand Yousef Sohrabi Gholamreza Heidari Weria Weisany Andrea Mastinu 《Molecules (Basel, Switzerland)》2022,27(10)
Nowadays, the use of the growth regulator salicylic acid for improving a plant’s resistance to environmental stresses such as drought is increasing. The present study investigated the effect of salicylic acid on the physiological traits, antioxidant enzymes, yield, and quality of Allium hirtifolium (shallots) under drought conditions for three years (2016–2017, 2017–2018, and 2018–2019). The experiment was conducted as a split-plot based on a randomized complete block design with four repeats. Irrigation as the main factor in four levels of 100% (full irrigation), 75% and 50% of the plant water requirements with non-irrigation (dryland), and salicylic acid as the sub-factor in four levels of 0, 0.75, and 1 mmol, were the studied factors in this research. The combined analysis of three-year data showed that drought reduced leaf relative water content (RWC), membrane stability index (MSI), chlorophyll content, onion yield, and increased activity of antioxidant enzymes, proline content, tang, and allicin of shallots. Shallot spraying with salicylic acid improved leaf RWC, MSI, chlorophyll content, and onion yield. The highest yield of onion (1427 gr m−2) belonged to full irrigation and foliar application of 1 mmol salicylic acid. The lowest yield (419.8 gr m−2) belonged to plats with non-irrigation and non-application of salicylic acid. By improving the effective physiological traits in resistance to water deficit, salicylic acid adjusted the effects of water deficit on the yield of shallots. Foliar application of 1 mmol salicylic acid in dryland and irrigation of 50% of the plant water requirement increased onion yield by 15.12% and 29.39%, respectively, compared to the control treatment without salicylic acid. 相似文献
22.
In the petroleum production industry wells are mostly cased and perforated in the producing formation. Perforation characteristics
such as size, length, number of perforation tunnels and their arrangements as well as fluid and rock properties determine
fluid flow behaviour in the wellbore region, hence, well productivity. Flow of gas and condensate around a perforation tunnel
(including the damaged zone) has been studied by performing steady-state core experiments and simulating the results numerically,
using a finite element modelling approach. The model allows for the changes in fluid properties and accounts for the coupling
of the two phases and the inertial effect using a fractional flow based correlation. The results indicated that different
sets of thickness-permeability (h−k) values obtained from matching single-phase flow performance could be assigned to the damaged zone around perforation to
represent the two-phase flow performance. The status of the tip of the perforation for two extreme cases of totally closed
and fully open was investigated and found to have a minimal effect on the performance of the system. 相似文献
23.
Emrarian Moona Sohrabi Mahmoud Reza Goudarzi Nasser Tadayon Fariba 《Structural chemistry》2021,32(1):49-61
Structural Chemistry - In this study, a quantitative structure–property relationship (QSPR) was proposed using the random forests (RF) and artificial neural network (ANN) for determining the... 相似文献
24.
S. Sohrabi 《Applicable analysis》2013,92(4):690-702
In this article, we present the uniform convergence analysis and accuracy estimation of hybrid functions (HFs) method for finding the solution of nonlinear Volterra and Fredholm integral equations. The properties of HFs which consist of block-pulse functions (BPFs) and Legendre polynomials are used to reduce the solution of nonlinear integral equations to the solution of algebraic equations. The superiority and accuracy of the HFs method to BPF and Legendre polynomial methods are illustrated through some numerical examples. 相似文献
25.
A new versatile electrochemical etching ECE chamber (VECE) system is introduced in which the effective electrochemically etched area can have variable sizes and/or shapes required using templet etching. The flat rubber washers act as templets and holders of the etchant, and control the size and shape of the effective etched area of the detector which can be of various shapes and sizes desired. The system was operated in two operation modes A and B in which the both sides and one side of the detector were etched respectively. Detectors with etched areas having diameters from 1 to 18 cm can have also been successfully etched by this system. Multi-chambers have been also designed using this principle for larger-scale multi-detector processing. The effects of etching area and time on the current through the detector have also been studied. 相似文献
26.
We use a method based on the conservation of energy, the mean-energy error criterion, to approximately locate the place of a cantorus by locating the series of its convergents. The mean-energy error curve has nearly stationary parts in the vicinity of elliptic (minimax) orbits, the so-called magnetic islands. Stable minimax orbits converge to orbits homoclinic to a cantorus. By tracing the island series, we limit the cantorus to a narrow region. A near-critical perturbation parameter is used so that, while the cantorus may be destabilized, its high-order minimax orbits remain intact. As illustrations, we consider two symplectic maps, systematically derived from the Hamilton–Jacobi equation and Jacobi’s theorem, in the context of the magnetically confined plasmas in a tokamak: a symmetric tokamap realistically reproduces the main features of a tokamak, and a symmetric ergodic magnetic limiter (EML) map is defined to describe the action of EML rings on the magnetic field lines in the tokamak. 相似文献
27.
A sensitive and fast method for the simultaneous determination of trace amounts of nickel and cadmium in real samples has been described using differential pulse adsorptive stripping voltammetry (DPASV) by adsorptive accumulation of the N,N′‐bis(salicylaldehydo)4‐carboxyphenylenediamine (BSCPDA)–complex on the hanging mercury drop electrode (HMDE). As supporting electrolyte 0.02 mol L?1 ammonia buffers containing ligand has been used. Optimal analytical conditions were found to be: BSCPDA concentration of 42 μM, pH 9.6 and adsorption potential at ?50 mV versus Ag/AgCl. With an accumulation time of 20 s, the peaks current are proportional to the concentration of nickel and cadmium over the 1–180, and 0.5–200 ng mL?1 with detection limits of 0.06 and 0.03 ng mL?1 respectively. The sensitivity of method for determination of nickel and cadmium were obtained 0.54 and 0.98 nA mL ng?1, respectively. The procedure was applied to simultaneous determination of nickel and cadmium in some real and synthetic artificial samples with satisfactory results. 相似文献
28.
Hamidreza Shahverdi Mehran Sohrabi Mahmoud Jamiolahmady 《Transport in Porous Media》2011,90(3):911-926
We present a new history matching method based on a Genetic Algorithm to estimate three-phase k
r (relative permeability) from unsteady-state coreflood experiments. In this method, relative permeabilities (k
r) are represented by quadratic B-Spline functions. Adjustable coefficients in k
r functions are changed in an iterative process to minimize an objective function. The objective function is defined as the
difference between the measures and simulated values of the pressure drop across the core and fluids recovery during the experiment.
One of the main features of this approach is that water and gas relative permeabilities (k
rw and k
rg) are assumed to be functions of two independent saturations as opposed to most of the existing empirical k
r models in which k
rw and k
rg are assumed to be only dependent of their own saturations. Another important aspect of this algorithm is that it considers
inequality constrains to ensure that physically acceptable k
r curves are maintained throughout the iterative optimization process. A three-phase coreflood simulator has been developed
based on this methodology that generates best k
r values by matching experimental data. The integrity of the developed software was first successfully verified by using two
sets of experimental three-phase k
r data published in the literature. Then, the results of some three-phase coreflood experiments carried out in our laboratory
were used to obtain three-phase k
r curves by this approach. 相似文献
29.
Mohammad Reza Rezaie Ali Negarestani Mehdi Sohrabi Saeed Mohammadi Dariush Afzali 《Journal of Radioanalytical and Nuclear Chemistry》2012,293(1):39-44
A new method is introduced in this paper for calculating alpha particle energy versus traveled distance (APETD) in air as emitted from 241Am and 230Th sources as well as the alpha range versus its energy and its energy versus distance. This method is to derive the stated relevant equations and in particular to speed up the calculation of E(x) by a Monte-Carlo simulation. By a fitting procedure, an analytical formula E(x) was determined in terms of a series of powers of distance x. Then a randomly sampled x can be quickly transformed into a corresponding energy E. The APETD calculations were run on a Microsoft Windows 7 32?bit operating system with a maximum usable memory of 3?GB. The results of calculations for alphas of the above two radionuclides in air compared to those of others using a different method are in good agreement. The above stated equations as derived in this paper are presented and the process time for applying the new method has been greatly improved. 相似文献
30.
Core-scale experiments and analyses would often lead to estimation of saturation functions (relative permeability and capillary pressure). However, despite previous attempts on developing analytical and numerical methods, the estimated flow functions may not be representative of coreflood experiments when it comes to predicting similar experiments due to non-uniqueness issues of inverse problems. In this work, a novel approach was developed for estimation of relative permeability and capillary pressure simultaneously using the results of “multiple” corefloods together, which is called “co-history matching.” To examine this methodology, a synthetic (numerical) model was considered using core properties obtained from pore network model. The outcome was satisfactorily similar to original saturation functions. Also, two real coreflood experiments were performed where water at high and low rates were injected under reservoir conditions (live fluid systems) using a carbonate reservoir core. The results indicated that the profiles of oil recovery and differential pressure (dP) would be significantly affected by injection rate scenarios in non-water wet systems. The outcome of co-history matching could indicate that, one set of relative permeability and capillary pressure curves can reproduce the experimental data for all corefloods. 相似文献