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951.
Ali Asghar Aslaminejad Mohammad Reza Nassiry Hadi Farajollahi Mohammad Hadi Sekhavati Ali Javadmanesh 《Food Biotechnology》2013,27(3):248-257
This study focused on the development and evaluation of a quantitative competitive polymerase chain reaction (QC-PCR) for detection and quantification of poultry DNA in sausage. PCR is well known to be quantitative if internal DNA standards are co-amplified together with the target DNA. A DNA competitor differing by 83 bp in length from the poultry target sequence was constructed and used for PCR together with the target DNA. Specificity of the new primers was evaluated with DNA from cattle and sheep. The results of QC-PCR showed that the percentage of contamination was in the range of 23.87–52.06%. 相似文献
952.
Mohammad Hojjati Ángel Calín‐Sánchez Seyed Hadi Razavi Ángel A. Carbonell‐Barrachina 《International Journal of Food Science & Technology》2013,48(2):437-443
Pistachios have been roasted following the Iranian traditional method (soaking in salty water, drying and roasting at 135 °C). Three Iranian pistachio cultivars (Ahmad Aghaei, Akbari and Kaleghouchi) were compared for their volatile compositions, colour and odour intensity. Lightness decreased in the course of roasting, which resulted from Maillard reaction. Raw pistachios had lower concentrations of most volatiles than roasted. A total of twenty‐six compounds were detected in roasted pistachios; these included aldehydes, terpenes, alcohols and only two pyrazines and one furan. These mixtures of volatiles implied that the Iranian roasting system is very soft, and samples retained most of the vegetable notes from fresh pistachios and some roasted notes were generated as well (from 2‐ethyl‐5‐methylpyrazine and 2,6‐dimethyl‐3‐ethylpyrazine). Sample from cultivar Akbari presented higher odour intensity than those by the other two cultivars, due mainly to higher concentrations of pyrazines developed during the roasting step. 相似文献
953.
Mohammad Reza Farzanegan 《Energy Economics》2011,33(6):1055-1069
Oil revenues play an important role in the political economy of Iran. On average, 60% of the Iranian government revenues and 90% of export revenues originate from oil and gas resources. Current international sanctions on Iran have mainly targeted the oil production capacity of Iran and its exports to the global markets. In this study, we analyze the dynamic effects of oil shocks on different categories of the Iranian government expenditures from 1959 to 2007, using impulse response functions (IRF) and variance decomposition analysis (VDC) techniques. The main results show that Iran's military and security expenditures significantly respond to a shock in oil revenues (or oil prices), while social spending components do not show significant reactions to such shocks. 相似文献
954.
Gholamreza Roohollahi Mohammad Kazemeini Alireza Mohammadrezaee Reza Golhosseini 《Journal of Industrial and Engineering Chemistry》2013,19(3):915-919
The effects of i-butane addition to methanol in MTP reaction were investigated over an in-house prepared HZSM-5 catalyst. It was observed that, propylene yield would be enhanced when i-butane fed to the reactor along with methanol. The rising growth of the propylene yield continued to peak on till the balance in thermal condition established. Similar trends have been observed when water was added to the mixture. The effect of WHSV with fixed water composition on product distribution was also studied. The optimum point where the highest amount of propylene yielded was shown to be high depended upon the temperature and residence time. 相似文献
955.
Davood Iranshahi Ali Mohammad BahmanpourEhsan Pourazadi Mohammad Reza Rahimpour 《International Journal of Hydrogen Energy》2010
In this study, a novel thermally coupled reactor containing the naphtha reforming process in the endothermic side and the hydrogenation of nitrobenzene to aniline in the exothermic side has been investigated. Considering the higher thermal efficiency as well as the smaller size of the reactor, utilizing the recuperative coupled reactor is given priority. In this novel configuration, the first and the second reactor of the conventional naphtha reforming process have been substituted by the recuperative coupled reactors which contain the naphtha reforming reactions in the shell side, and the hydrogenation reaction in the tube side. The achieved results of this simulation have been compared with the results of the conventional fixed-bed naphtha reforming reactors. Acceptable enhancement can be noticed in the performance of the reactors. The production rate of the high octane aromatics and the consumption rate of the paraffins have improved 17% and 72%, respectively. The conversion of the nitrobenzene is acceptable and the effect of the number of the tubes also has been taken into account. However, the performance of the new configuration needs to be tested experimentally over a range of parameters under practical operating conditions. 相似文献
956.
Mohammad S. S. Tavakolian Florina A. Silaghi Angelo Fabbri Giovanni Molari Alessandro Giunchi Adriano Guarnieri 《International Journal of Food Science & Technology》2013,48(6):1282-1288
The world production of dates has more than doubled over the last two decades. Presently, the industrial sorting of dates is a difficult operation, affected by a high level of losses. As a consequence, the objective of this article is to study the variety discrimination capabilities of Fourier Transform‐Near Infrared (FT‐NIR) reflectance spectroscopy for post‐harvest sorting purposes. The same methodology was tested on six commercial date varieties named Estamaran, Kabkab, Mazafati, Piarom, Deglet nour and Zahedi. For each cultivar, 100 fruits were analysed using the FT‐NIR spectrometer, subsequently characterised by destructive measurements. A multivariate analysis of the FT‐NIR spectra appears a feasible tool for cultivar discrimination and even to estimate the soluble solid content (SSC) and dry matter (DM) of dates at their optimal harvesting conditions. FT‐NIR, as a non‐destructive techniques, could be a suitable way for on‐line screening of different dates varieties. 相似文献
957.
Mohammad Reza Akbari Jokar Ali Shoja Sangchooli 《The International Journal of Advanced Manufacturing Technology》2011,54(5-8):801-809
Solving the facility layout problems by graph theory consists of two stages. In the first stage, a planar graph that specifies desired adjacencies is obtained and in the second stage, a block layout is achieved from the planar graph. In this paper, we introduce face area as a new concept for constructing a block layout. Based on this idea, we present a new algorithm for constructing block layout from a maximal planar graph (MPG). This MPG must be generated from deltahedron heuristic. Constructed block layout by this algorithm satisfies all of adjacency and area requirements. 相似文献
958.
Mohammad Izadi Author Vitae Author Vitae 《Pattern recognition》2009,42(7):1361-1634
In this paper, an improved active contour model based on the time-adaptive self-organizing map with a high convergence speed and low computational complexity is proposed. For this purpose, the active contour model based on the original time-adaptive self-organizing map is modified in two ways: adaptation of the speed parameter and reduction of the number of neurons. By adapting the speed parameter, the neuron motion speed is determined based on the distance of each neuron from the shape boundary which results in an increase in the speed of convergence of the contour. Using a smaller number of neurons, the computational complexity is reduced. To achieve this, the number of neurons used in the contour is determined based on the boundary curvature. The proposed model is studied and compared with the original time-adaptive self-organizing map. Both models are used in several experiments including a tracking application. Results reveal the higher speed and very good performance of the proposed model for real-time applications. 相似文献
959.
Mohammad G. Mohammad Masoud Hassanpour Vicky W. W. Tsai Hui Li Marc J. Ruitenberg David R. Booth Jordi Serrats Prue H. Hart Geoffrey P. Symonds Paul E. Sawchenko Samuel N. Breit David A. Brown 《International journal of molecular sciences》2013,14(1):547-562
Multiple sclerosis (MS) is a devastating neurological disease that predominantly affects young adults resulting in severe personal and economic impact. The majority of therapies for this disease were developed in, or are beneficial in experimental autoimmune encephalomyelitis (EAE), the animal model of MS. While known to target adaptive anti-CNS immune responses, they also target, the innate immune arm. This mini-review focuses on the role of dendritic cells (DCs), the professional antigen presenting cells of the innate immune system. The evidence for a role for DCs in the appropriate regulation of anti-CNS autoimmune responses and their role in MS disease susceptibility and possible therapeutic utility are discussed. Additionally, the current controversy regarding the evidence for the presence of functional DCs in the normal CNS is reviewed. Furthermore, the role of CNS DCs and potential routes of their intercourse between the CNS and cervical lymph nodes are considered. Finally, the future role that this nexus between the CNS and the cervical lymph nodes might play in site directed molecular and cellular therapy for MS is outlined. 相似文献
960.
Saeed Olyaee Mohammad Shams Esfand Abadi Samaneh Hamedi Fatemeh Finizadeh 《International Journal of Hydrogen Energy》2011,36(20):13255-13265
In this paper, we present an interferometry method for refractive index determination in membranes of fuel cells. This technique is based on the use of an improved laser heterodyne interferometer. The photocurrents of the avalanche photodiodes, resulting from reflected beams of the optical head, are led to the signal conditioner and digital signal processing sections. The optical path difference between the target and reference paths is fixed, and as a result, the phase shift is calculated in terms of the refractive index shift. In addition, nonlinearity of this system is analyzed and modeled with different neural networks and adaptive filter algorithms. For neural networks, the radial basis function (RBF), the multi-layer perceptron (MLP), and the stacked generalization method are simulated. In adaptive filter algorithms, the least mean square (LMS), the normalized least mean square (NLMS), the recursive least squares (RLS), and the affine projection algorithm (APA) are applied. The simulation results indicate that the RLS method is faster and contains minimum mean square error (MSE) compared to the other approaches. Also, comparison between two main approaches shows that the nonlinearity of refractive index determination can be effectively modeled with adaptive filter algorithms. 相似文献