javad khalilzadeh

Due to the limitations of conventional biological identification methods, spectroscopic methods, including laser induced breakdown spectroscopy, have been used to characterize the genus, species and strains of different bacteria in the static phase of growth. Due to the increading importance of biological problems, the characterization, detection and classification of bacterial specimens has been considered by researchers in the military, industrial and medical fields. In this paper, in order to monitor the changes in the elemental structure of bacteria in the growth process, the constituent elements of the two phases of exponential and static growth of Escherichia coli were studied and compared based on this spectroscopic method. In this experiment, Nd: YAG laser with 100 mJ pulse energy, spectrometer and CCD detector were used. The industrial strain of gram-negative Escherichia coli BL21 bacteria was selected. Bacteria were selected at three different times (2.5, 4 and 6 hours after inoculation) during the growth process in broth, at optical density of 0.4 and 0.8 (exponential growth phase) and optical density of 1.2 (Static growth phase), respectively, and after dry freezing, under pressure has been pressed into tablets. Considering the chemical structure of Escherichia coli, the elements of phosphorus, carbon, calcium, sodium, magnesium, potassium, oxygen, nitrogen and hydrogen were considered in the sample. The results showed that Escherichia coli bacteria in the growth process have different patterns of recognizable elemental composition in its structure in the growth process. It is predicted that due to the change in the composition of structural elements of bacteria in growth phases, the use of this spectroscopic method to identify bacteria will be dependent on the growth phase. The results of this study showed that this method can play an effective role in the development of polyphasic methods to indentify bacteria, determine the composition of the culture medium as well as optimizing and evaluating the production conditions in this industrial strain.

In this paper, the performance of a high-sensitivity, low-cost, low-dimensional Fabry-Perot based fiber-optic sensor for measuring argon gas pressure is reported. A Fabry-Perot sensor probe with an air cavity, length of 1.25 mm and suitable diaphragm with different thicknesses has been investigated in order to achieve the optimal thickness. The ultimate goal is to achieve a diaphragm that detects and measures gas pressures below 80 millibars. A PVC layer was used as second Fabry-Perot plate of the sensor,The sensing experimental arrangement for measuring gas pressure was provided in the laboratory. The effect of gas pressure as well as diaphragm thickness as an important parameter on the sensitivity of gas pressure sensor was investigated. Diaphragm thicknesses of 42, 56 and 70 μm and cavities with a length of 1.25 mm were investigated at different pressures of argon gas. The results showed that the best sensitivity with a value of 0.035 nm / mbar is related to the sensor with a diaphragm thickness of 42 μm.

The most important and effective part of any light detector is the photocathode. In this research, in order to improve the efficiency of the photocathode optical response, the plasmonic phenomenon is used and a new photocathode is designed and simulated based on the finite difference time domain (FDTD) method. By designing a periodic nano-grating on the surface, a structure is presented that makes it possible to couple the incoming light to an electron density wave on the surface. Plasmonic resonance is created in the desired wavelength range and the field strength is greatly increased. In this way, the metal-semiconductor becomes an excellent absorber. For this purpose, photocathodes with planar and non-planar (nano- grating) structures consisting of GaAs and Au are simulated separately. Then, the plasmonic nano- grating structure consisting of Au-GaAs composite materials is simulated and compared with the plasmonic nano- grating structure of gold, so that the absorption rate of the structure is increased by 16.1%. The plasmonic nano- grating structure consisting of Au-GaAs in the visible spectrum shows better performance in increasing the photocathode efficiency due to higher absorption. The structure provided for the photocathode has the advantage of filtering the incoming light with excellent accuracy and quality. Another important feature is the creation of multiple resonant frequencies simultaneously with the formation of repetitive geometry.

In this paper, a novel biosensor based on the photonic crystal for refractive index measurements is proposed and investigated. Three designs, known as single-cavity structure, duble and triple-cavities structures, are designed and studies. All the structures were composed of a main hole as a ring resonator localized between the input and output waveguides. Two-dimensional finite-difference time domain and plane-wave expansion methods are employed to study the output power spectrum of the structures. By absorbing DNA molecules in the PBS solution, the refractive index of the sensing holes differ which results to the output transmission spectrum of the structure shift and hence, the sensing process occure. We study the impact of different parameters on the sensing of the structures. Results show that the sensitivity of the sensor depends mainly on the geometrical properties of the defect region of the photonic crystal structure. Results shows that the single cavity and triplet structures have the best sensitivity equal to 345nm/RIU and 531compared to the other proposed sensors, respectivelly.

This study discussed the role of oil revenues and banking sector credits with an emphasis on monetary policy in Iranchr('39')s economy in the form of a dynamic dynamic equilibrium model. In this study was used real seasonal per capita data for the period of 1996 to 2017 and the seasonal adjustment utilized by the Hadrik-Proskat filter and Calibration method to extract the parameters of the general equilibrium model.For this purpose, first, the model of justification and the equations of each section were explained based on theoretical foundations and some previous studies. Then optimization of each section was done by solving its equations and the model was simulated based on the economic realities of Iran and subsequently, the simulated model was fitted with the help of variables moments that the results confirm the relative success of the simulated model with the realities of Iranchr('39')s economy. Also, the immediate response to the governmentchr('39')s oil revenue shock on variables was examined, The results showed that any positive shocks to government oil revenues would lead to an expansionary fiscal policy by the government that This increases household incomes and, while stimulating the demand side, increases household consumption by increasing household consumption. An increase in the volume of household deposits also means more funds available to banks, which will result in lower interest rates and an increase in the supply of bank loans to increase investment in enterprises and increase production that the results are in line with the theoretical expectations and economic realities of the country.

This paper proposes a novel plasmonic sensor for biological applications such as single-stranded DNA detection that it is simulated and analyzed using the FDTD method. The sensor detects the adsorption of DNA molecules in the sensing solution (PBS) by changes in the reflectance of the structure. The mechanism of this sensor is based on the variation of refractive index with the absorption of different concentrations of molecules. The proposed structure consists of metal (gold/silver)-indium tin oxide (ITO)-graphene and an assay medium. The results showed that the ITO metal oxide layer plays an important role in the sensor parameters. By optimizing the thicknesses of metals (gold and silver), the metal oxide, and graphene, we obtained the maximum sensitivity of 75 deg/RIU for the gold-graphene-analyte structure and the maximum detection limit of 58.33 for the silver-ITO-analyte structure. The structures proposed in this paper outperform those presented in previous works. Thus, the proposed biosensor is able to open a new window for biomolecule detection.

In this paper, the effect of government expenditures with the volume of bank credits on economic growth in Iran, considering the role of monetary policy in the form of a dynamic stochastic genral equilibrium model is studied. for this purpose, we first defined a model consisting of households, production sector, government and oil, banks and intermediary financial institutions and the monetary status for the Iranian economy. Then, the model of the study was specified and the equations of each section were explained. After specifying the assumptions, characteristics and relationship of different parts of the model with each other, each section was optimized. After simulating the model, the model was fitted with real and simulated ratios and also using the torque variables and finally, the effects of the impuls response to the shock of government expenditures on the variables of production, consumption, investment, facilities and bank deposits were investigated that in many cases, the results have been consistent with the theoretical expectations and economic realities of the country.

In this paper, we report simulation and fabrication of a gas sensor based on tapered fiber by measuring the output power in the presence of different hydrogen concentrations. The fibers were tapered to 15.5 μm and 26.6 μm by using oxy-butane torch and the output spectrum is obtained using a 1550nm laser source and an optical spectrum analyzer (OSA) and the sensitivities of the tapered fiber sensors were determined. It is shown that by increasing the percentage of the hydrogen in the surrounding environment, the output power is changed by 7% and 2.3% in the presence of 4% hydrogen for tapered fibers of diameter 15.5μm and 26.6 μm respectively. The response time of the aforementioned sensors were 13 and 17.6 seconds respectively. In addition, the repeatability tests of the fabricated sensors demonstrates acceptable results. Simulation of the tapered fiber sensors demonstrates good agreement with experimental results. The obtained sensitivity makes hydrogen detection below 4% easy and accurate.

This study has investigated the challenges of financing of Iranian manufacturing institutions, considering the function of monetary policy and banking sector's credits in the form of a DSGE model. For this, the real per-capita of seasonal data of 1995 to 2014 that have been deterending by Hodrick-Prescott Filtering and the calibration method were used to extract the parameters. After modeling and explaining the equations of each section, in relation to optimization and simulation of the model using variable moments were performed. The results obtained confirmed the relative success of the simulated model with the realities of Iran's economy. Afterwards, the functions of the instant reaction to productivity shock and the shock of growth in money volumes were reviewed. The results showed that the positive shock of productivity and the growth of the volume of money increased the production via the channel of increasing investment and lowering interest rates respectively. That the results were consistent with the theoretical expectations and economic realities of Iran.

In this research, laser listening countermeasure using absorbing layers deposited on surface of glass, which is located infront of the sound source was investigated experimentally. To do this, samples with one, two and three-layers of Al2O3, TiO2, MgF2, have made and used. Deposition performed by evaporation technique on BK7 glass substrate using electron gune beam. During the deposition, the optical thickness was controlled by the thickness monitoring system.Reflectance of gayers and relative intensity of the reflected beam from the coated glass surface were measured due to investigation of the effect of anti-reflective layers. Using the TFD Scope simulation software the sound graph was evaluated too.The results showed that at 632.8 nm laser wavelength, the sample coated by three layers of Al2O3 and TiO2, MgF2 significantly reduces the reflection of the laser beam to less than one percent.

Gold and silver nanoparticles have antibacterial and antimicrobial properties and microbes do not grow on their surfaces. These materials can be used in cosmetics, medical and textile industries in forms of antibacterial gel and antibacterial cloths. In the present work has been Al2O3 nanoparticles doped by Ag in vitro and production of these materials according to their antibacterials properties has biological and medical applications is enormous. Subjects and Al(NO3)3•9H2O, NH4HCO3, AgNO3, Deionized water, Ethanol.Production of Nanoparticles by precipitaton. In this experiment, alumina nanoparticles doped with silver is synthesized and for confirmation of results we have used XRD technique and Sherrer formula. Finally, it is found that alpha phase of nanoparticles has been formed. Al2O3 doped with Ag composite activate by silver oxygen to produce active oxygen and beside SiO2 or TiO2 semiconductor acts as an electrochemicall cell. By oxidizing oxygen atom it produces oxygen ion and by hydrolysis of water, produced. The produced ions are very strong antibiological agents.

Despite the benefits of world trade organization (WTO) membership on the economy, it may also have undesirable effects. So the countries that have done sufficient studies about effects of WTO membership on their economies before entering WTO, can change its threats into opportunity and use its advantages. Therefore we have tried to study the effects of WTO membership on a small part of the Iran economy. To this aim an economic model was designed and has been estimated. This model consists of agriculture sector inflation as dependent variable and liquidity or bank credits to agriculture sector, agriculture sector GDP, globalization or integration index, and weighted average of input prices in agriculture sector as independent variables. In order to study and analyze the relationship among variables, we used Microfit software and Johansen co-integration method with annual time series data of 1981-2013. Our results of "Johanson-Juselius" approach confirmed long term co-integration relation among the variables of the model, so the existence of two co-integrated vectors is confirmed. Also in order to study structural break and the stability of estimated coefficients of model we used "accumulation sum of recursive residuals" test, the results of this test showed the stability of estimated coefficients. Finally by estimation variance decomposition, it was cleared that trade liberalization index has positive effect on dependent variable of the model.

The main objective of this study is to investigate the impact of oil price shocks on value-added of industrial sector، within the theoretical framework of the Dutch disease. Co-integration method is applied to evaluate and test hypothesis، using data during 1978-2010. We have first introduced a VAR model of value-added of industry using previous studies. Then، after investigating the stationary status of the variables and determining optimal lag length، the effect of shocks on the co-integration vector and the test of cumulative recursive sum of residuals were carried out to verify the presence of structural breaks. Finally، we investigated the long-run equilibrium relationship among variables. The results show that there is no long-run equilibrium relationship among the variables. Analysis of the results shows that rise in oil revenues has a direct impact on the real exchange rate and domestic inflation and، it also has an indirect negative effect on the value-added of industry. The results indicate that the best way to deal with this phenomenon in the country is proper management of foreign exchange fund to prevent excess liquidity in the economy.

In this paper, the effect of discharge region temperature on the yield of singlet oxygen (O2 (a 1∆g)) in an electric discharge oxygen iodine laser is theoretically studied to analyze optimum discharge conditions. This study, was done by considering the saturation of O2 (a 1∆g) due to super-elastic electron collisions and O2 (a 1∆g) dissociation by electron impact. Rate equations were solved using two terms approximation of Boltzmann equation. The results show that when the electron temperature was in the Te= 1.9-2.1 eV range, it causes removing the main part of the atomic oxygen O (3P) from the discharge region, and the maximum yield of O2 (a 1∆g) was obtained to be about 45%.

Privatization for reduction of government tenure and increase of its performance from several decades ago on in most countries such as Iran has been implemented which "Iran's police force" as well following this act has assigned some of its services such as "second grade drivers license" training and test to private sectors. In this paper which is the result of a research as the same title, has been tried to analyze the implementation effects of this project on three components 1 reduction of trainees expenses, 2 - rate of success in learning driving rules by trainees and 3 - trainees satisfaction ( second grade drivers license applicants).The population which is studied is two groups of " trainees" and "private driving schools staffs in Julfa, and Marand that sample is classified and selected by using systematic sampling . After two groups proportion determination (trainees and staff), questionnaire distributed to mentioned groups. For analysis of data deductive statistics has been employed in which results show the positive effect of this project on three mentioned component. Also, two groups views were compared which shows same mean and no considerable different between views.

Institutions of higher education were previously thought to be the centre of knowledge production and dissemination, but now they are expected to have a more active role in the development of national and regional economies, as well. Responding to the new expectation has currently led them to internal changes and evolution in how they interact with the social and economic environments. This change has created a new generation of entrepreneurial universities. The leading indicator activity of such universities is the creation of university‘s Spin-off. According to the laws and directives of our country, these companies are supposed to be Knowledge-based, founded by the outcomes of the university researches and acted in the field of high tech. But some universities, in our country, exceed the expectations and establish manufacturing and service-companies of their own. In other words, they’re, little by little, becoming manufacturing firms. Since the traditional mission of universities is teaching and research, some conflicts arose between the main mission of the universities (research and teaching) and the new task of entrepreneuring. This paper examines these conflicts and finally provides suggestions to resolve these conflicts. This paper is a descriptive - analytical study and data is collected by using library resources, electronic research databases, author’s experience and In-depth interview with a technology-park authorities and managers of the company established in above mentioned incubator.

Institutions of higher education were previously thought to be the centre of knowledge production and dissemination, but now they are expected to have a more active role in the development of national and regional economies, as well. Responding to the new expectation has currently led them to internal changes and evolution in how they interact with the social and economic environments. This change has created a new generation of entrepreneurial universities. The leading indicator activity of such universities is the creation of university‘s Spin-off. According to the laws and directives of our country, these companies are supposed to be Knowledge-based, founded by the outcomes of the university researches and acted in the field of high tech. But some universities, in our country, exceed the expectations and establish manufacturing and service-companies of their own. In other words, they’re, little by little, becoming manufacturing firms. Since the traditional mission of universities is teaching and research, some conflicts arose between the main mission of the universities (research and teaching) and the new task of entrepreneuring. This paper examines these conflicts and finally provides suggestions to resolve these conflicts. This paper is a descriptive - analytical study and data is collected by using library resources, electronic research databases, author’s experience and In-depth interview with a technology-park authorities and managers of the company established in above mentioned incubator.

Purpose active material is one of the important components of solid state laser. Solid state laser were called base on active material. That emit in specific wavelength. Target of this work is fabrication of laser glass as new host laser active material for achieving visible laser. Fabrication These glasses with composition in mol% of 42.5P2O5, 12Na2HPO4, 25CaF2, 15NaF, 5SiO2, 0.5Nd2O3 were prepared. These glasses were fabricated by heat melting method. Thermal properties of the glasses were investigated by thermal analysis. Absorption in infrared and visible range by Eclipse varion set were took. Up conversion luminescence measurement in the 1064 nm were performed with Nd:YAG laser and S100 spectrometer. Glass transition temperature 640oC and glass crystallization temperature 700oC were obtained. Absorption spectra indicate wavelength picks in 426, 496, 510, 525, 582, 746, 802 and 874 nm that are in agreement with those found in previous reports. According to the up conversion emission, the emission bands were achieved at 560, 620, 640nm. In the research work, fabrication of Nd3+ doped oxyfluorophosphate glasses was sucsesfull. In which observed upcoversion properties of infrared to visible range.

In this computational research, a photonic crystal filter has been designed to protect passive defense sensors in α- band of IR radiation and its performance at 2.8 µm Hydrogen-Fluoride laser has been studied. The photonic crystal assumed to be a silicon elliptical bars at air background with trigonal geometry was designed. Optimum geometry for 2.5 µm wave was found and its filteration performance for considered laser wavelength was examined. Such a filter with considered large and small diameters show desired performance.

One of the important aspects of stealth technology in advanced warships design has been discussed In this paper. In warships, infrared suppression is vital to mitigate threats against infrared guided missiles. Infrared radiation is introduced and then definition of the physical concepts of spectral emission and radiance and introduction of theoretical expression are represented. Ships infrared emission sources and methods of their suppression were studied and infrared suppression systems common in advanced military ships are listed.