Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

Journal Issue Information

Archive

Year

Volume(Issue)

Issues

Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
Author(s): 

MORADI M. | SHAHRI H.

Issue Info: 
  • Year: 

    2003
  • Volume: 

    3
  • Issue: 

    4
  • Pages: 

    275-280
Measures: 
  • Citations: 

    0
  • Views: 

    274
  • Downloads: 

    0
Abstract: 

The Helmholtz free energy and equation of the state of an fcc crystal are calculated, where the interaction between the molecules is hard sphere-Yukawa potential. Here the perturbational density functional method is used. This method is introduced by Ebner and co-workers. In this method the density functional Taylor expansion is applied for the crystal configuration up to second order. And for the uniform parts an exact expression is used. The results are compared with those obtained by Monte Carlo computer simulation. The agreement is good.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

View 274

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesDownload 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesCitation 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesRefrence 0
Issue Info: 
  • Year: 

    2003
  • Volume: 

    3
  • Issue: 

    4
  • Pages: 

    281-288
Measures: 
  • Citations: 

    0
  • Views: 

    257
  • Downloads: 

    0
Abstract: 

We present the QCD models based on the hadronization of final states of e+e- annihilations, in 60 GeV centre of mass energy in the AMY detector at the KEK collider TRISTAN to achieve this, we first find the jet axis by using the momentum tensor and diagonilizing it for each event. The models under consideration are the Webber, the Matrix Elements and the Parton Shower. In most cases our results are consistent with the models. Our results are also consistent with those obtained from other experiments.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

View 257

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesDownload 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesCitation 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesRefrence 0
Issue Info: 
  • Year: 

    2003
  • Volume: 

    3
  • Issue: 

    4
  • Pages: 

    295-300
Measures: 
  • Citations: 

    0
  • Views: 

    267
  • Downloads: 

    0
Abstract: 

Large Hadron Collider (LHC) at CERN will provide excellent opportunity to study the production and decay of heavy mesons and baryons with high statistics. We aim at the heavy mesons in this work and calculate their fragmentation functions consistent with this machine and present their total fragmentation probabilities and average fragmentation parameters.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

View 267

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesDownload 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesCitation 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesRefrence 0
Author(s): 

NASIRI S. | ABEDINI A.

Issue Info: 
  • Year: 

    2003
  • Volume: 

    3
  • Issue: 

    4
  • Pages: 

    309-316
Measures: 
  • Citations: 

    0
  • Views: 

    274
  • Downloads: 

    0
Abstract: 

The site selection procedure for optical observatories housing a telescope with a sizeable aperture is described. The theory of seeing is briefly introduced and a special type of seeing monitor that is widely used for seeing measurements is discussed. The results of the meteorological studies mainly based on the wind-rose diagrams are presented. These are done for 31 preliminary selected candidate sites using the data obtained from meteorological synoptic stations during the last 20 years.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

View 274

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesDownload 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesCitation 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesRefrence 0
Issue Info: 
  • Year: 

    2003
  • Volume: 

    3
  • Issue: 

    4
  • Pages: 

    97-100
Measures: 
  • Citations: 

    0
  • Views: 

    1954
  • Downloads: 

    0
Abstract: 

Two continuous-wave (cw) single mode diode-lasers (Toshiba TOLD 9150 and Sharp LT024MDO) are applied as pump and signal sources to obtain difference-frequency generation (DFG) in the mid-infrared (MIR) region by using an AgGaS2 crystal with a length of 30 mm for 90° type I phase-matching. Tunable MIR laser radiation around 5µm is obtained with an output power in the order of hundred nW while the diode lasers are operated at 20 and 30 n W around their center wavelengths 789 and 681 nun, respectively. To demonstrate the applicability of this MIR-DFG laser spectrometer we recorded the absorption spectrum of CO for the P (21) rotational line at 2055.4 cm-1 in a 10 cm long cell and in the flame of a McKenna burner in order to estimate the self-broadening coefficient of CO, the collisional-broadening of CO with CO2, and the CO concentration distribution in the flame.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

View 1954

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesDownload 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesCitation 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesRefrence 0
Author(s): 

DELDAR S.

Issue Info: 
  • Year: 

    2003
  • Volume: 

    3
  • Issue: 

    4
  • Pages: 

    101-104
Measures: 
  • Citations: 

    0
  • Views: 

    637
  • Downloads: 

    0
Abstract: 

The potentials between static sources in various representations in SU(3) are calculated on the basis of the fat-centre-vortices model of Faber, Greensite and Olejník. At intermediate distances, potentials are in qualitative agreement with "Casimir scaling", which says that the string tension is proportional to the quadratic operator of the representation. At large distances, screening occurs for zero-triality representations; for the representations with non-zero triality the sting tension equals that of the fundamental representation.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

View 637

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesDownload 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesCitation 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesRefrence 0
Author(s): 

GHOMINEZHAD M. | AKHAVAN M.

Issue Info: 
  • Year: 

    2003
  • Volume: 

    3
  • Issue: 

    4
  • Pages: 

    257-274
Measures: 
  • Citations: 

    0
  • Views: 

    1094
  • Downloads: 

    0
Abstract: 

We have successfully synthesised and studied the bilayer ferrofluids with sodium oleate C18H33O2-Na+as the first layer and sodium dodecyle sulfate C12H25Na+SO-4 (SDS) as the second layer surfactants. The solid phase of the ferromagnetic colloidal system was formed based on quick chemical growth. The adsorption of oleate molecule on the surface of the solid solution has been investigated by IR spectroscopy. The XRD analysis of the oxides and titration by KMnO4 show that the closest stoichiometry of Fe3O4 is achieved by the increase of Fe3+/Fe2+ molar ratio up to 2/3 with extra acidifying for prevention of uncontrolled Fe2+ excitation. The X-ray diffraction and magnetic measurements by VSM were employed for determining the particle magnetic and crystal sizes. The particle size was determined to be 9-13 run. The magnetisation measurement of the ferrofluid indicate a saturation magnetisation of about 1.5 emu/g and reduced initial susceptibility of 6×10-3 Oe-1, which are the proper values for a superparamagnet. However, the saturation magnetisation shows a local maxima at SDS concentration about 0.07M, which is different from the behaviour presented by the mono-layer ferrofuids.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

View 1094

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesDownload 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesCitation 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesRefrence 0
Issue Info: 
  • Year: 

    1382
  • Volume: 

    4
  • Issue: 

    4
  • Pages: 

    275-279
Measures: 
  • Citations: 

    0
  • Views: 

    1141
  • Downloads: 

    0
Abstract: 

در این مقاله انرژی آزاد و معادله حالت بلور fcc به روش نظریه چگالی مورد بررسی قرار گرفته است. برهمکنش بین مولکولها از نوع پتانسیل کره سخت-یوکاوا می باشد. در این محاسبات روش اختلال پیشنهاد شده توسط ابنر مورد استفاده قرار است و بسط انرژی آزاد برحسب چگالی تا مرتبه دوم با در نظر گرفتن آرایش بلوری می باشد که جمله مرتبه صفرم مربوط به انرژی یکنواخت به صورت عبارت دقیق انرژی مایع یکنواخت در چگالی کپه ای جامد در نظر گرفته شده است. نتایج به دست آمده با نتایج شبیه سازی کامپیوتری تطابق خوبی دارد.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

View 1141

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesDownload 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesCitation 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesRefrence 0
Issue Info: 
  • Year: 

    1382
  • Volume: 

    4
  • Issue: 

    4
  • Pages: 

    281-287
Measures: 
  • Citations: 

    0
  • Views: 

    796
  • Downloads: 

    0
Abstract: 

در این مقاله مدلهای گوناگون مبنی بر هادرونی شدن ذرات را مورد بررسی قرار می دهیم. برای این منظور ابتدا محور جت را با استفاده از تانسور تکانه و قطری کردن آن برای هر رویداد به دست می آوریم. این تحلیل را با بهره گیری از آشکارساز AMY در حلقه انباشت e+e- در انرژی مرکز جرم 60Gev  در شتابدهنده TRISTAN واقع در KEK ژاپن انجام داده ایم. مدلهای مورد مطالعه عبارتند از: مدل وبر، مدل عناصر ماتریسی و مدل بارش پارتون. در اکثر موارد این مدلها پیشگویی های صحیحی از الگوی هادرونی شدن ارائه می دهند. نتایج حاصل از داده های AMY نیز با این مدلها سازگاری دارند.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

View 796

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesDownload 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesCitation 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesRefrence 0
Author(s): 

SADEGHI E.

Issue Info: 
  • Year: 

    2003
  • Volume: 

    3
  • Issue: 

    4
  • Pages: 

    289-294
Measures: 
  • Citations: 

    0
  • Views: 

    1081
  • Downloads: 

    0
Abstract: 

Energy eigenvalues of carriers have been calculated for rectangular quantum wires with finite barrier potentials using the effective mass approximation. Ga0.47In0.53As/InP and GaAs/ Ga0.63Al0.37  As systems are considered, and a spatially dependent effective mass is included in effective mass approximation. Calculated values are compared with those obtained earlier by other methods. Experimental values of the energy shift of Ga0.47In0.53As/InP wires are also compared with the calculations.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

View 1081

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesDownload 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesCitation 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesRefrence 0
Issue Info: 
  • Year: 

    1382
  • Volume: 

    4
  • Issue: 

    4
  • Pages: 

    295-299
Measures: 
  • Citations: 

    0
  • Views: 

    536
  • Downloads: 

    0
Abstract: 

با راه اندازی برخورد دهنده LHC در مرکز CERN امکان بررسی تولید و واپاشی مزونها و باریونهای سنگین با آمار بالا فراهم خواهد شد. در کار حاضر مزونهای سنگین را مورد توجه قرار داده و با محاسبه توابع ترکش آنها در شدایط  LHC، احتمال کل ترکش و مقدار متوسط پارامتر ترکش را برای آنها ارائه می دهیم.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

View 536

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesDownload 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesCitation 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesRefrence 0
Author(s): 

NASR ESFAHANI B.

Issue Info: 
  • Year: 

    2003
  • Volume: 

    3
  • Issue: 

    4
  • Pages: 

    301-308
Measures: 
  • Citations: 

    0
  • Views: 

    907
  • Downloads: 

    0
Abstract: 

Regarding the static form of Maxwell's equations in wormhole background geometry, we obtain a generalised form of Laplace's equation. Because of peculiar geometry of the throat, lines of force that enter the wormhole at one mouth and emerge from the other, initially converge and then diverge. So, for a remote observer the wormhole can act as a charge distribution that modifies the potential, mainly around the throat. Here, the exact solutions for the potential are obtained and by considering an equivalent dielectric media and finding polarisation charge distributions the effect of the wormhole geometry on the potential is justified. It is assumed that real sources of the potential are distributed far from the throat and do not contribute to the stress-energy tensor of the wormhole.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

View 907

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesDownload 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesCitation 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesRefrence 0
Issue Info: 
  • Year: 

    1382
  • Volume: 

    4
  • Issue: 

    4
  • Pages: 

    309-315
Measures: 
  • Citations: 

    0
  • Views: 

    480
  • Downloads: 

    0
Abstract: 

در این مقاله به بررسی گلبادهای مناطق کاندید کشور برای تاسیس رصدخانه ملی ایران می پردازیم. تلاطم حاصل از باد و تاثیر مستقیم آن بر وضعیت دید نجومی به عنوان مهمترین پارامتر مکانیابی توضیح داده می شود. سپس نتایج بررسی گلبادها، نمودارهای سرعت متوسط و درصد بادهای آرام مربوط به مناطق کانید بر اساس داده های 31 ایستگاه سینوپتیک هواشناسی در 20 سال اخیر گزارش می گردد.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

View 480

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesDownload 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesCitation 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesRefrence 0
Author(s): 

JAAFARI E.

Issue Info: 
  • Year: 

    2003
  • Volume: 

    3
  • Issue: 

    4
  • Pages: 

    317-322
Measures: 
  • Citations: 

    0
  • Views: 

    810
  • Downloads: 

    0
Abstract: 

Here we study the rotational structure of CF4 molecule for ground state v4 mode, fine structure step by using J. Moret-Bailly theory. First the calculated spectra are normalized to the experimentally measured spectra, for calculating the centrifugal and coriolis constants up to the third approximation, D0 =-3.18× 10-3 cm-1, (4)ξ0=1.33×10-1 cm-1. Then the rotational energies are calculated for J≤6.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

View 810

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesDownload 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesCitation 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic ResourcesRefrence 0
telegram sharing button
whatsapp sharing button
linkedin sharing button
twitter sharing button
email sharing button
email sharing button
email sharing button
sharethis sharing button