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مرکز اطلاعات علمی SID1
مرکز اطلاعات علمی SID
اسکوپوس
مرکز اطلاعات علمی SID
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نویسندگان: 

SAFARI REZA | SABZYAN HASSAN

اطلاعات دوره: 
  • سال: 

    2014
  • دوره: 

    11
  • شماره: 

    6
  • صفحات: 

    1513-1532
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    19655
  • دانلود: 

    9450
چکیده: 

The electronic and vibrational atomic responses to external electric field (EF) are computed to detail intramolecular energy transfer in a proposed molecular nanoelectronic field-effect system. The parallel and perpendicular electronic and vibrational contributions to intramolecular energy transfer are computed using, respectively, quantum theory of atoms-in-molecule and an energy partitioning scheme based on normal modes vibrational analysis. The symmetrical and asymmetrical intramolecular energy transfers are interpreted, respectively, as Peltier-like and Joule-like effects and quantified in terms of appropriate coefficients. Dependencies of these coefficients on EF are investigated. In addition, a semiclassical temperature model is introduced to describe symmetrical and asymmetrical temperature distributions which are attributed, respectively, to the Joule-like and Peltier-like heatings. This procedure can be used to map out intramolecular energy distribution in molecular nanoelectronic systems.

آمار یکساله:  

بازدید 19655

دانلود 9450 استناد 0 مرجع 0
اطلاعات دوره: 
  • سال: 

    2013
  • دوره: 

    0
  • شماره: 

    16
تعامل: 
  • بازدید: 

    2310
  • دانلود: 

    0
کلیدواژه: 
چکیده: 

INTRODUCTION: THE CRUCIAL IMPORTANCE OF PROTON transfer REACTIONS BETWEEN PROTON DONORS AND ACCEPTORS IN THE BIOLOGICAL energy CONVERSION PROCESS IS WIDELY KNOWN. SOME OF THE PROTON transfer REACTIONS OCCUR IN THE PRESENCE OF OTHER PROCEDURES SUCH AS ELECTRON transfer. THE PROCESSES OF OXYGEN EVOLUTION IN PHOTOSYNTHESIS AND OXIDATION PROCESSES IN MITOCHONDRIA ARE THE EXAMPLES IN WHICH THE PROTON ALONG WITH ELECTRON transfer REACTIONS OCCUR ADDITIONALLY HYDROGEN BONDED SYSTEMS HAVE THE HIGHEST IMPORTANCE IN BIOLOGY, SOLUTION CHEMISTRY AND ACID-BASE SYSTEMS. FOR A NOTABLE EXAMPLE, THE PRESENCE OF HYDROGEN BONDS IN AMINO ACIDS IS IMPORTANT FOR THE FINAL THREE DIMENSIONAL STRUCTURES OF PROTEINS SUCH AS TERTIARY AND QUATERNARY STRUCTURES. THIS SIGNIFICANCE OF PROTON transfer REACTION AND HYDROGEN BONDED SYSTEMS CREATES A CENTER OF ATTENTION FOR SCIENTISTS AND MANY STUDIES HAVE BEEN DONE TO UNDERSTAND THE CHEMISTRY OF PROTON transfer REACTION. IN THIS RESEARCH, THERMODYNAMICS OF intramolecular HYDROGEN transfer BETWEEN ENOLE AND KETONES WERE CHOSEN TO STUDY THEIR THERMODYNAMICS AND KINETICS.

آمار یکساله:  

بازدید 2310

دانلود 0
عنوان: 
اطلاعات دوره: 
  • سال: 

    1383
  • دوره: 

    0
  • شماره: 

    7
تعامل: 
  • بازدید: 

    30
  • دانلود: 

    11
چکیده: 

پیشرفت روزافزون کامپیوترها و متعاقب آن توسعه نرم افزارهای طراحی صنعتی پروسه طاقت فرسای طراحی و ساخت ادوات و ماشین آلات حتی پیچیده را سهل و آسان نموده و با ایجاد فضائی قرین با واقعیت به مهندسین طراح امکان نگرش جامع بر ساخت و عملکرد ماشین آلات را پیش از آنکه عمل شکل دهی، ساخت و بهره برداری آنها به واقع آغاز گردد، فراهم می نماید.انتقال مواد در مراکز صنعتی بخش قابل ملاحظه ای از فعالیتهای روزمره را در بر می گیرد. طراحی و ساخت یک نمونه ماشین انتقال بار transfer car با قابلیت جابجائی بر روی ریل در پروسه ساخت یک واحد صنعتی مد نظر بوده است. این عمل با تهیه مدل کامپیوتری و با استفاده از نرم افزارهای Solid Works، Cosmos Works و Design Star انجام شده است. انتخاب مواد و پروفیل فلزات مورد نیاز منطبق با محصولات موجود در بازارهای داخلی انجام پذیرفته و نتایج بر اساس استاندارد طراحی DIN تنظیم شده اند. همچنین معیارهای متداول در طراحی برای کنترل پروژه و حصول ضرایب اطمینان مناسب مورد استفاده قرار گرفته اند. طرح نهائی پس از گذراندن آزمونهای ضروری، تحت پروسه های لازم برای ساخت قرار گرفته است.

آمار یکساله:  

بازدید 30

دانلود 11
گارگاه ها آموزشی
نویسنده: 

NEKOEI A. REZA | KEYHANIAN MASOOMEH

اطلاعات دوره: 
  • سال: 

    2015
  • دوره: 

    0
  • شماره: 

    18
تعامل: 
  • بازدید: 

    1680
  • دانلود: 

    0
چکیده: 

BACKGROUND: ENOL FORMS OF B-DIKETONE COMPOUNDS HAVE CAPABILITY OF FORMATION A RELATIVELY STRONG intramolecular HYDROGEN BOND (IHB). BECAUSE OF CONSEQUENTIAL ROLE OF THESE COMPOUNDS IN INDUSTRY [1-2], INVESTIGATION OF THEIR IHB STRENGTH IS OF SIGNIFICANT IMPORTANCE. …

آمار یکساله:  

بازدید 1680

دانلود 0
اطلاعات دوره: 
  • سال: 

    2014
  • دوره: 

    0
  • شماره: 

    17
تعامل: 
  • بازدید: 

    2310
  • دانلود: 

    0
چکیده: 

BACKGROUND: GLUTATHIONE (GSH) IS A PHYSIOLOGICALLY IMPORTANT TRIPEPTIDE (CONSISTING OF GLUTAMATE, CYSTEINE AND GLYCINE) [1]. ABERRANT LEVELS OF GSH HAVE BEEN ASSOCIATED WITH A NUMBER OF DISEASES, INCLUDING CANCER, AIDS, ALZHEIMER‟S AND CARDIOVAS [2]. A SIMPLE AND EFFICIENT COLORIMETRIC METHOD FOR THE NAKED-EYE DETECTION AND QUANTIFICATION OF GSH IN BIOLOGICAL FLUIDS WAS DEVELOPED [3]. THIS ABSTRACT FOCUSES ON THE COLORIMETRIC SENSORS FOR GSH ACCORDING TO intramolecular CHARGE transfer (ICT) MECHANISMS BETWEEN SENSORS AND GSH. WE USED SOLOCHOROM DARK BLUE (CALCON) FOR THIS SENSOR AS AN ELECTRON DONOR–ACCEPTOR COMPOUND. THIS COMPOUND WITH STRONG ICT CHARACTER WAS DESIGNED AS A COLORIMETRIC SENSOR FOR DETECTION GSH.METHODS: IN THIS RESEARCH, CATIONIC DYE CALCON WAS ADDED TO BORATE BUFFER IN OPTIMAL CONDITIONS (PH=9, CONCENTRATION DYE= 0.001).THEN DIFFERENT AMINO ACID SOLUTIONS WITH CONCENTRATION OF 0.001M ADDED. ABSORPTION SPECTRUM OF SOLUTIONS WAS MEASURED. CHANGING IN ABSORPTION SPECTRUM WITH ADDED GSH SOLUTION CHANGES SOLUTION COLOR FROM BLUE TO VIOLET.RESULTS: COLOR OF CHEMOSENSOR CHANGES FROM BLUE TO VIOLET WITHIN ABSORPTION SPECTRUM WAVELENGTH FROM 576 NM TO 650 NM. LINEAR RANGE AND LOW DETECTION LIMIT WERE CALCULATED FOR THIS CHEMOSENSOR WHICH RESPECTIVELY ARE 4.62×10-6- 4.867×10-5 M AND 3.591×10-7 M.CONCLUSION: IN THIS INVESTIGATION, WE HAVE DEVELOPED A COLORIMETRIC CHEMOSENSOR CALCON WITH AMINO ACID GSH IN AQUEOUS ENVIRONMENT. WE REPORTED A SIMPLE AND EASY WAY TO MAKE RECEPTOR (CALCON) THAT RESPOND EFFICIENTLY IN THE ICT MECHANISM FOR NACKED-EYE DETECTION OF GSH AMONG OTHER KIND OF AMINO ACIDS.

آمار یکساله:  

بازدید 2310

دانلود 0
اطلاعات دوره: 
  • سال: 

    2015
  • دوره: 

    3
  • شماره: 

    1
  • صفحات: 

    54-61
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    18062
  • دانلود: 

    12488
چکیده: 

Nanofluid is a new class of heat transfer fluids engineered by dispersing metallic or non-metallic nanoparticles with a typical size of less than 100 nm in the conventional heat transfer fluids. This article aims to investigate the overall and convection heat transfer coefficient and Nusselt number of Al2o3-water nanofluid flowing in a horizontal double pipe heat exchanger under turbulent flow (14000 £Re£ 26500) conditions. Al2o3 nanoparticles with diameter of 20 nm dispersed in Deionized water with volume concentrations of 0.1% £ j £ 0.3% vol. are used as the test fluid. The results show that the overall and convection heat transfer coefficient and Nusselt number of nanofluid were approximately 15% -21% greater than that of pure fluid. Additionally, the heat transfer coefficient and Nusselt number increase with an increase in flow rate, Reynolds number, nanoparticle concentration and nanofluid temperature. Finally, the new correlations were proposed for predicting the Nusselt number of the nanofluids, especially. Employing particles of nanometer dimension suspended in solution as nanofluid shows considerable increase in the nanofluid thermal conductivity and heat transfer coefficient which result in increasing heat transfer and decreasing operational cost.

آمار یکساله:  

بازدید 18062

دانلود 12488 استناد 0 مرجع 0
strs
اطلاعات دوره: 
  • سال: 

    2016
  • دوره: 

    0
  • شماره: 

    19
تعامل: 
  • بازدید: 

    1365
  • دانلود: 

    0
کلیدواژه: 
چکیده: 

IN THIS WORK, intramolecular PHOTO-INDUCED PROTON transferS IN 6-HYDROXY-7H-BENZO[C]FLUOREN-7- ONE (HBFO) AND ITS SUBSTITUTED COMPOUND IN GAS PHASE ARE INVESTIGATED USING TD-DFT METHOD AT M06-2X/6- 311++G(D,P) LEVEL OF THEORY.. ..

آمار یکساله:  

بازدید 1365

دانلود 0
نویسنده: 

RAMEZANI T.

اطلاعات دوره: 
  • سال: 

    2016
  • دوره: 

    0
  • شماره: 

    19
تعامل: 
  • بازدید: 

    1365
  • دانلود: 

    0
کلیدواژه: 
چکیده: 

IN THIS EXPLORE, THE CALCULATION OF GROUND STATE intramolecular PROTON transfer (GSIPT) AND EXCITED STATE intramolecular PROTON transfer (ESIPT) ON 2-(3H-INDOL-2-YL) PHENOL DERIVATIVES WAS CARRIED OUT AT THE PBE1PBE/6-311++G(2D,2P) LEVEL OF THEORY. THE POTENTIAL energy SURFACES WERE CALCULATED FOR GROUND AND EXCITED STATES. ...

آمار یکساله:  

بازدید 1365

دانلود 0
نویسنده: 

ROOHI H. | MOTAMEDIFAR N.

اطلاعات دوره: 
  • سال: 

    2013
  • دوره: 

    0
  • شماره: 

    16
تعامل: 
  • بازدید: 

    945
  • دانلود: 

    0
کلیدواژه: 
چکیده: 

PHOTOINDUCED ELECTRON transfer AND PROTON transfer ARE THE FUNDAMENTAL PROCESSES IN THE REALM OF PHOTOCHEMISTRY. EXTENSIVE INTEREST HAS BEEN SHOWN BY THE PHOTOSCIENTISTS IN STUDYING EXCITED STATE INTER AND intramolecular PROTON transfer (ESPT AND ESIPT, RESPECTIVELY) REACTIONS OWING TO, IN PARTICULAR, THEIR SIMPLICITY AND DIVERSE APPLICATIONS [1].PROTON transfer IS ONE OF THE MOST FUNDAMENTAL REACTIONS, AND IT IS FOUND UBIQUITOUSLY IN CHEMICAL AND BIOLOGICAL PROCESSES. VARIOUS TYPES OF PROTON transfer HAVE BEEN REPORTED IN BOTH THE GROUND AND EXCITED STATES. EXCITED STATE intramolecular PROTON transfer (ESIPT) HAS RECEIVED MUCH ATTENTION BECAUSE OF THE SIMPLICITY OF ITS REACTION PATTERN. THE ESIPT SYSTEM GENERALLY REQUIRES HYDROGEN BONDING FORMATION BETWEEN VICINAL PROTON DONOR AND PROTON ACCEPTOR GROUPS [2]. IN THIS WORK, WE REPORTED OUR INVESTIGATION ON ESIPT, BASED ON THE EFFECT OF ATOMS SUBSTITUTIONS S, O AND N ON THE DERIVATIVES OF COMPOUND A. THE intramolecular PROTON transfer (IPT) IN THE GROUND (GSIPT) AND EXCITED (ESIPT) STATES OF A DERIVATIVES WERE STUDIED USING DFT-PBE1PBE/6-311++G (2D, 2P) AND TDDFTPBE1PBE/ 6-311++G (2D, 2P) LEVELS OF THEORY, RESPECTIVELY.POTENTIAL energy CURVES, DIPOLE MOMENT, REACTION COORDINATE AND OTHER GEOMETRIC PARAMETERS HAVE BEEN INVESTIGATED. THE RESULTS REVEALTHAT THE IPT PROCESS DOES NOT OCCUR IN THE GROUND STATE BUT IT IS FEASIBLE IN THE S1 STATE.

آمار یکساله:  

بازدید 945

دانلود 0
نویسنده: 

NAZARNEZHAD N.

اطلاعات دوره: 
  • سال: 

    2016
  • دوره: 

    0
  • شماره: 

    18
تعامل: 
  • بازدید: 

    1470
  • دانلود: 

    0
کلیدواژه: 
چکیده: 

THE EXCITED-STATE intramolecular PROTON transfer PROCESS (ESIPT) HAS BEEN INVESTIGATED IN THE S1 AND T1 STATES OF [2, 2′-BIPYRIDYL] -3, 3′-DIOL USING THE CIS METHOD. STATIC INVESTIGATION OF STATIONARY POINTS HAS BEEN PERFORMED BY DFT METHOD. THESE CALCULATIONS SHOW THAT THE CONCERTED DIPROTON transfer IN T1 PROCEEDS AND DIKETO (DK) FORM IS STABLE FORM IN THIS STATE....

آمار یکساله:  

بازدید 1470

دانلود 0
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