فهرس المقالات Electron beam

• حرية الوصول المقاله
  • صفحة الملخص
  • نص كامل
  
  1 - Investigation of the Poynting flux ratio in the helix traveling wave tube
  Shahrooz Saviz Mona Mehranfar Davoud Dorranian
  10.30495/jtap.162203
  The study deals with amplification of a propagating slow wave interacting with an annular hollow electron beam in a helix slow wave structure (SWS). The role of thermal plasma density in a ratio of the axial pointing flux in the plasma region is also investigated. This أکثر

  The study deals with amplification of a propagating slow wave interacting with an annular hollow electron beam in a helix slow wave structure (SWS). The role of thermal plasma density in a ratio of the axial pointing flux in the plasma region is also investigated. This ratio is small for lower plasma densities. The effects of the variations of the hollow electron beam velocity on the normalized growth rate and the poynting flux ratio at the hybrid mode frequency are presented. The maximum gain is obtained in the frequency of hybrid mode and the poynting flux ratio reaches its maximum value at the hybrid mode frequency. Also is analyzed the trend of changes for the normalized growth rate for a different beam velocities. The results show that for all beam velocities the maximum growth rate is for hybrid mode frequencies. The numerical method used in this paper is complex transcendental. تفاصيل المقالة
• حرية الوصول المقاله
  • صفحة الملخص
  • نص كامل
  
  2 - Dispersion characteristics of plasma-filled cylindrical waveguide
  Sh. M. Khalil N. M. Mousa
  10.1007/s40094-014-0111-2
  AbstractAn analytical and numerical study is made on the dispersion properties of a cylindrical waveguide filled with plasma. An electron beam and static external magnetic field are considered as the mechanisms for controlling the field attenuation and possible stabilit أکثر

  AbstractAn analytical and numerical study is made on the dispersion properties of a cylindrical waveguide filled with plasma. An electron beam and static external magnetic field are considered as the mechanisms for controlling the field attenuation and possible stability of the waveguide. The effects of plasma warmness and inhomogeneity are also considered. Dispersion relations in ω describing different physical situations that govern the mode propagation in the waveguide are obtained. The plasma dielectric tensors and the dispersion relations which describe E and H waves and, hence, the damping rate of these waves are calculated and studied. The necessary conditions for the field stability in the waveguide and amplification coefficients for these waves are also obtained. H-wave modes are always attenuated by collisional effect. The growth of the excited E wave is calculated in the resonance case, and the stability condition for the E wave is obtained. E waves are found to be more stable in warm plasma compared to cold plasma. The results obtained here are of great interest and may be used to analyze how the plasma affects the electromagnetic properties of the cavity of the 1–2 MW 140–170 GHz continuous-wave gyrotron (for W7-X stellarator and ITER), for MW gyrotron development for fusion plasma applications, and for second harmonic generation in a plasma-filled parallel plane waveguide. تفاصيل المقالة
• حرية الوصول المقاله
  • صفحة الملخص
  • نص كامل
  
  3 - Development of low-pressure high-current plasma cathode electron gun and use of associated techniques
  Udit Narayan Pal Niraj Kumar Deepak Kumar Verma Jitendra Prajapati Mahesh Kumar Vishnu Srivastava Harish Kumar Dwivedi Ram Prakash
  10.1186/2251-7235-6-36
  AbstractA plasma cathode electron (PCE) gun has capabilities for generating high-current, broad, and focused beams for plasma-assisted microwave sources. A pseudospark-based hollow cathode PCE gun has been designed and developed for microwave generation which is operate أکثر

  AbstractA plasma cathode electron (PCE) gun has capabilities for generating high-current, broad, and focused beams for plasma-assisted microwave sources. A pseudospark-based hollow cathode PCE gun has been designed and developed for microwave generation which is operated in argon atmosphere. An analysis of the electron beam profile inside the drift space at different operating conditions has been carried out. This has been performed at several axial and radial locations inside the drift space which shows coherent phases of beam profiles in radial direction. The focusing and defocusing points in axial direction are also obtained. The beam current at different axial location for different applied voltages has been estimated. The obtained beam current is in close agreement with the beam current estimated by the particle-in-cell simulation code for the same geometry. تفاصيل المقالة
• حرية الوصول المقاله
  • صفحة الملخص
  • نص كامل
  
  4 - Theoretical analysis of a thermal plasma-loaded relativistic traveling wave tube having corrugated slow wave structure with solid electron beam
  Zahra Javadi Shahrooz Saviz
  10.1007/s40094-014-0160-6
  AbstractA relativistic traveling wave tube with thermal plasma-filled corrugated waveguide is driven by a finite solid electron beam with the entire system immersed in a strong longitudinal magnetic field that magnetized plasma and electron beam. The dispersion relation أکثر

  AbstractA relativistic traveling wave tube with thermal plasma-filled corrugated waveguide is driven by a finite solid electron beam with the entire system immersed in a strong longitudinal magnetic field that magnetized plasma and electron beam. The dispersion relation for the relativistic traveling wave tube is obtained by linear fluid theory. The numerical results show that the growth rate decreases by increasing plasma temperature, waveguide radius, plasma density and electron beam energy. As show in this paper the effect of electron beam density and corrugation period is to increase growth rate. تفاصيل المقالة
• حرية الوصول المقاله
  • صفحة الملخص
  • نص كامل
  
  5 - Dispersion relation and growth rate in thermal plasma-loaded traveling wave tube with corrugated waveguide hollow electron beam
  Samina Dehghanizadeh Shahrooz Saviz
  10.1007/s40094-015-0168-6
  Abstract A theory of relativistic traveling wave tube with magnetized thermal plasma-filled corrugated waveguide with annular electron beam is given. The dispersion relation is obtained by linear fluid theory. The characteristic of the dispersion relation is obtained by أکثر

  Abstract A theory of relativistic traveling wave tube with magnetized thermal plasma-filled corrugated waveguide with annular electron beam is given. The dispersion relation is obtained by linear fluid theory. The characteristic of the dispersion relation is obtained by numerical solutions. The effect of plasma density, corrugated period, waveguide radius and plasma thermal effect on the dispersion relation and growth rate are analyzed. Some useful results are given. تفاصيل المقالة
• حرية الوصول المقاله
  • صفحة الملخص
  • نص كامل
  
  6 - Nonlinear study of injection process types into the traveling wave tube with hollow electron beam
  H. Bayati S. Saviz A. H. Sari
  10.1007/s40094-019-0327-2
  AbstractIn this paper, examples of all types of signal injection such as different signal , harmonic signal and multiple signal injections in a TWT including hollow electron beam near frequency 1800 MHz and within input powers lower than TWT saturation power has been an أکثر

  AbstractIn this paper, examples of all types of signal injection such as different signal , harmonic signal and multiple signal injections in a TWT including hollow electron beam near frequency 1800 MHz and within input powers lower than TWT saturation power has been analyzed using approximate analytical solution of S-MUSE model. Later, the results obtained from approximate analytical solution with large signal code LATTE, that is a Lagrangian model, have been tested and simulated so that the effect of input phase difference between drive and injected wave and the effect of input powers on the amplification value of drive and generated second-order harmonic waves were investigated. The phase difference between drive and harmonic waves is a key parameter in harmonic injection for increasing the output power of drive and second-order harmonic frequencies. تفاصيل المقالة
• حرية الوصول المقاله
  • صفحة الملخص
  • نص كامل
  
  7 - Enhancement of charge breeding efficiency for rare isotope beam with the control of magnetic field profile and electron beam energy in EBIS
  J. W. Kim
  10.1007/s40094-020-00388-z
  AbstractThe magnetic field in the ion trap of electron beam ion source (EBIS) determines the current density of electron beam and thus the depth of trap potential, which affects the charge breeding efficiency to desired charge state. An EBIS charge breeder has been cons أکثر

  AbstractThe magnetic field in the ion trap of electron beam ion source (EBIS) determines the current density of electron beam and thus the depth of trap potential, which affects the charge breeding efficiency to desired charge state. An EBIS charge breeder has been constructed to be used for the Rare Isotope Science Project in Korea. A 6 T superconducting solenoid is used for the trap, and uniform magnetic field is extended with correction coils at the ends. The effect of field uniformity on the electron current density is evaluated using TRAK, and it is shown sizable improvement in the charge breeding efficiency for rare isotope beams can be obtained by elaborate magnetic design. Furthermore, the electron beam energy affects the ionization efficiency. The electron energy is often reduced in the trap for optimal matching with charge striping cross section. However, virtual cathode formation can appear in the process of energy reduction. Maximum beam currents limited by electron energy are studied analytically and by TRAK simulation in the view of improving the charge breeding efficiency. تفاصيل المقالة
• حرية الوصول المقاله
  • صفحة الملخص
  • نص كامل
  
  8 - روش نوین تصفیه آب و فاضلاب با استفاده از باریکه های الکترونی
  سید محمد موسویان
  ورود فزاینده انواع آلاینده به محیط زیست و وضع استانداردهای زیست محیطی سخت گیرانه و عدم توانایی روش های معمول تصفیه برای حذف کامل و یا کاهش آلاینده ها به سطح مطلوب منجر به مطالعه و توسعه فرایندهای تصفیه جدید نظیر باریکه های الکترونی شده است. تاباندن باریکه های الکترونی ب أکثر

  ورود فزاینده انواع آلاینده به محیط زیست و وضع استانداردهای زیست محیطی سخت گیرانه و عدم توانایی روش های معمول تصفیه برای حذف کامل و یا کاهش آلاینده ها به سطح مطلوب منجر به مطالعه و توسعه فرایندهای تصفیه جدید نظیر باریکه های الکترونی شده است. تاباندن باریکه های الکترونی به آب و فاضلاب، باعث تولید هم زمان گونه های فعال احیاءکننده و اکسیدکننده (aq-e، H●، (OH● می شود که به سرعت و به صورت غیرانتخابی با ترکیبات آلاینده واکنش داده و آن ها را تجزیه نمایند. در این مقاله، سابقه استفاده از باریکه های الکترونی و کاربردهای آن در کنترل آلودگی زیست محیطی در مقیاس های مختلف و شتاب دهنده های الکترونی به عنوان تجهیزات تولیدکننده باریکه های الکترونی، راکتورهای مورد استفاده برای تابش باریکه های الکترونی، عوامل موثر در کارایی این روش و سیستم های باریکه های الکترونی ارایه شده است و با توجه به نقاط قوت این روش نسبت به روش های متداول تصفیه و همچنین هزینه کم تر و عملکرد بهتر آن به خصوص در زمینه گندزدایی فاضلاب و لجن و حذف رنگ از فاضلاب صنایع، دور از ذهن نیست که در آینده نزدیک به عنوان یکی از فناوریهای مهم در حفظ محیط زیست معرفی گردد. تفاصيل المقالة
• حرية الوصول المقاله
  • صفحة الملخص
  • نص كامل
  
  9 - هدایت باریکه الکترونی حاصل از شتابدهنده های الکترونی به داخل بافت جهت درمان توسط هدایتگرنانوتیوب های کربن
  محبوبه باقری پرویز زبده
  امروزه درمان با الکترون به دلیل مزایایی مانند همگنی دز در حجم هدف، کاهش دزدریافتی توسط بافت های سالم، بی تاثیر بودن حباب هوایی که بافت هدف را احاطه کرده بر دزانتقال یافته نسبت به درمان های فوتونی ، و توانایی کنترل و افزایش تعداد باریکه های به کاربرده شده برای درمان، مور أکثر

  امروزه درمان با الکترون به دلیل مزایایی مانند همگنی دز در حجم هدف، کاهش دزدریافتی توسط بافت های سالم، بی تاثیر بودن حباب هوایی که بافت هدف را احاطه کرده بر دزانتقال یافته نسبت به درمان های فوتونی ، و توانایی کنترل و افزایش تعداد باریکه های به کاربرده شده برای درمان، مورد توجه بوده و در اکثرمراکز درمانی جایگزینی ندارد. باریکه الکترونی توانایی درمان در زمینه تومورهای سطحی (تا عمق حدود 20 سانتی متر) را دارد . در این مطالعه برای اولین بار، با ارائه طرح یک هدایت گر انعطاف پذیر الکترونی در هنگام خروج باریکه الکترونی از شتابدهنده های الکترونی، افزایش موثرکارایی درمان های الکترونی بیان شده است، از مزایای عمده آن عدم محدودیت به عمق درمان یا به عبارتی عدم محدودیت درمان های سطحی، و توانایی درمان تومورهای داخلی تر توسط باریکه الکترون و عدم آسیب به بافت سالم، می باشد. از مزایای عمده آن عدم محدودیت به عمق درمان یا به عبارتی عدم محدودیت درمان های سطحی، و توانایی درمان تومورهای داخلی تر توسط باریکه الکترون و عدم آسیب به بافت سالم، می باشد. تفاصيل المقالة
• حرية الوصول المقاله
  • صفحة الملخص
  • نص كامل
  
  10 - تحلیل و ارائه یک سیکل عملیات حرارتی بهینه پس از جوش جهت کاهش حداکثری تنش‌های پسماند جوشکاری پرتو الکترونی
  حسین رجبی علی حیدری
  در این تحقیق، فرآیند جوشکاری پرتو الکترونی لب به لب دو ورق فولادی P91 در دو‌بعد و در مدت زمان کوتاه با دقت قابل قبول در دو مرحلة تحلیل غیر کوپله حرارتی و مکانیکی به انجام رسیده است. نتایج تنش‌های پسماند با نتایج آزمایشگاهی و عددی محققان دیگر اعتبارسنجی شده است که تطابق أکثر

  در این تحقیق، فرآیند جوشکاری پرتو الکترونی لب به لب دو ورق فولادی P91 در دو‌بعد و در مدت زمان کوتاه با دقت قابل قبول در دو مرحلة تحلیل غیر کوپله حرارتی و مکانیکی به انجام رسیده است. نتایج تنش‌های پسماند با نتایج آزمایشگاهی و عددی محققان دیگر اعتبارسنجی شده است که تطابق خوبی را نشان می‌دهد. در ادامه تحقیق با اعمال عملیات حرارتی بعد از جوشکاری سعی شده است تنش‌های پسماند کاهش پیدا کند. سپس تأثیر پارامترهای سیکل عملیات حرارتی مانند میزان توان حرارت ورودی، زمان حرارت‌دهی، زمان نگه داشتن دما و ضریب انتقال حرارت جابجایی در بازه سرد شدن بر روی میزان کاهش تنش پسماند بررسی شده است. با بررسی نتایج تأثیرات پارامترها، یک سیکل عملیات حرارتی بهینه جهت کاهش حداکثری تنش پسماند ارائه شده است که با اعمال این سیکل بهینه تنش پسماند ماکزیمم به میزان 55 درصد کاهش یافته است. تفاصيل المقالة
• حرية الوصول المقاله
  • صفحة الملخص
  • نص كامل
  
  11 - Band-Gap Tuning Of Electron Beam Evaporated Cds Thin Films
  Mohamad Javad Eshraghi Nima Naderi
  The effect of evaporation rate on structural, morphological and optical properties of electron beam evaporated CdS thin films have been investigated. CdS thin film deposited by electron beam evaporation method in 12nm/min and 60nm/min evaporation rates on glass substrat أکثر

  The effect of evaporation rate on structural, morphological and optical properties of electron beam evaporated CdS thin films have been investigated. CdS thin film deposited by electron beam evaporation method in 12nm/min and 60nm/min evaporation rates on glass substrates. X-ray diffraction, scanning electron microscopy, UV-Vis-NIR spectroscopy and Atomic Force Microscopy were used to characterize thin films. The x-ray diffraction analysis confirms that films have polycrystalline hexagonal phase and exhibited preferred orientation along the (002) plane. The crystallite size were calculated and found to be increased from 23 nm to 30 nm by increasing deposition rate. Results of Atomic Force Microscopy revealed that the RMS roughness values of the CdS films decreased as deposition rate increased. The relation between deposition rates and optical properties of deposited films was investigated. It was found that stoichiometric properties and band gap values of the deposited films are correlated to deposition rates. These dependencies are associated to the Cd/S ratio variation by deposition rate. The optical band gap values of CdS films increased slightly in a range of 2.32–2.34 eV for deposition rate varied from 12nm/min and 60nm/min . تفاصيل المقالة
• حرية الوصول المقاله
  • صفحة الملخص
  • نص كامل
  
  12 - Improving the Nutritional Value of Sunflower Meal by Electron Beam and Gamma Ray Irradiations
  F. Ghanbari T. Ghoorchi P. Shawrang H. Mansouri N.M. Torbati-Nejad
  This research was performed to compare electron beam (EB) and gamma ray (GR) treatments at doses of 25, 50 and 75 kilo Gray (kGy) on ruminal degradation kinetics and in vitro digestibility of sunflower meal (SFM). Ionizing radiations of EB and GR had significant effects أکثر

  This research was performed to compare electron beam (EB) and gamma ray (GR) treatments at doses of 25, 50 and 75 kilo Gray (kGy) on ruminal degradation kinetics and in vitro digestibility of sunflower meal (SFM). Ionizing radiations of EB and GR had significant effects )P<0.05( on dry matter (DM), crude protein (CP) and amino acid (AA) degradability parameters of SFM. Effective ruminal degradability (ERD) of DM was lower in EB and GR irradiated SFM than in unirradiated SFM) P<0.05(. GR treatment at a dose of 75 kGy decreased ERD of CP compared to control )P<0.05(. ERD of CP was not affected by EB )P>0.05(. Irradiation processing caused a decrease in AA degradation after 16 h of ruminal incubation significantly )P<0.05(. GR irradiation was more effective than EB irradiation in lessening the ruminal degradability of AA.In vitro CP digestibility of EB and GR irradiated SFM was improved )P<0.05(. This study, based on in situ andin vitro measures, showed that EB and GR processing can be used as an efficient method in improving nutritional value of SFM. تفاصيل المقالة
• حرية الوصول المقاله
  • صفحة الملخص
  • نص كامل
  
  13 - Chemical cross linking versus high energy electron beam cross linking of HDPE: electrical properties study
  Nooredin Goodarzian Mohammad Amin Shamekhi
  Cross linking of high density polyethylene (HDPE) was first performed via high energy10 Mev electron beam (EB) irradiation. HDPE was also cross linked withDicumyle peroxide (DCP).The gel content of samples was determined by solvent extraction.Degree of cross linking was أکثر

  Cross linking of high density polyethylene (HDPE) was first performed via high energy10 Mev electron beam (EB) irradiation. HDPE was also cross linked withDicumyle peroxide (DCP).The gel content of samples was determined by solvent extraction.Degree of cross linking was evaluated by hot set apparatus; as well .In order to clarify the effectof nature of cross linking, correlation of electrical properties such as volume resistively,dielectric constant, dielectric strength with the type of cross linking system was made. It wasfound that, in the same amount of gel content, electrical properties of samples cross linked by thetwo methods, differed. تفاصيل المقالة