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4848

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مرکز اطلاعات علمی SID1
مرکز اطلاعات علمی SID
اسکوپوس
مرکز اطلاعات علمی SID
ریسرچگیت
strs
اطلاعات دوره: 
  • سال: 

    2014
  • دوره: 

    0
  • شماره: 

    22
تعامل: 
  • بازدید: 

    2205
  • دانلود: 

    0
چکیده: 

HEXAGONAL STRUCTURED MESOPOROUS SILICA OR ALUMINA SILICA (E.G.MCM-41 AND sba-15) HAVE BEEN EXTENSIVELY STUDIED. [1] THEIR HIGH SPECIFIC SURFACE AREA, POROUS VOLUME AND ADJUSTABLE PORE SIZE MAKE THEN IDEAL SUPPORTS FOR THE PREPARATION OF HIGHLY DISPERSED HETEROGENEOUS CATALYSTS. [2, 3] THESE MATERIALS HAVE ATTRACTED SIGNIFICANT ATTENTION IN ACADEMIC RESEARCH AND THEY HAVE FOUND NOTABLE APPLICATIONS IN INDUSTRY LIKE PETROCHEMICAL INDUSTRY.CONSIDERING THE ABOVE POINTS, WE STUDIED A SIMPLE METHOD TO PREPARE SILVER SUPPORTED MESOPOROUS sba-15 AND COPPER SUPPORTED MESOPOROUS sba-15 BY VARIOUS AG AND CU INORGANIC SALTS. THE RESULTS WE OBTAINED ARE INTERESTING AND COMPARABLE.IN THE NEXT PART OF THIS RESEARCH THE EFFECTS OF NEWLY SYNTHESIZED AG-sba-15 AND CU-sba-15 ON THE SYNTHESIS OF COMPOUNDS 4 ARE INVESTIGATED.BENZALDEHYDE1, MALONONITRILE 2 AND 3-METHYL-1H-PYRAZOL-5-ONE3 ARE CONDENSED IN THE PRESENCE OF AG-sba-15 OR CU-sba-15 IN HIGH YIELDS. THE NANO CATALYSTS ARE EASILY RECOVERED AND CAN BE SUCCESSFULLY REUSED FOR SEVERAL TIMES WITHOUT LOSING REACTIVITY. THE NEW ASPECTS AND RESULTS OF THESE PROCEDURES WILL BE PRESENTED AND DISCUSSED.

آمار یکساله:  

بازدید 2205

دانلود 0
اطلاعات دوره: 
  • سال: 

    2014
  • دوره: 

    0
  • شماره: 

    22
تعامل: 
  • بازدید: 

    1155
  • دانلود: 

    0
چکیده: 

RECENTLY USING MESOPOROUS CATALYSTS HAVE BEEN SHOWN INCREASING ATTRACTION IN ORGANIC SYNTHESIS [1]. ON THE OTHER HAND IMINOCOUMARIN DERIVATIVES ARE AN IMPORTANT GROUP OF FLUORESCENT ORGANIC COMPOUNDS RECENTLY CONSIDERABLE EFFORTS HAS BEEN ATTENDED TO THE DEVELOPMENT OF COLORIMETRIC AND FLUORESCENT CHEMOSENSORS BASED ON IMINOCOUMARIN [2, 3]. WE HAVE ALREADY REPORTED THE PROCEDURES FOR SYNTHESIS OF A LIBRARY OF FLUORESCENT COMPOUNDS [4]. HERE WE WISH TO REPORT A HIGHLY EFFICIENT SYNTHESIS OF NOVEL DYES CONSISTING AZO IMINOCOUMARIN USING sba-15. AZO DYES1 IN THE PRESENCE OF AG-sba-15 OR ZR-sba-15 CONDENSED WITH MALONONITRILE TO PRODUCE THE 2 AND 3, WHICH CAN BE USED FOR FURTHER RESEARCH. STRUCTURES 2 AND 3 ARE ELUCIDATED FROM THEIR IR, UV-VISIBLE, 1HNMR, 13CNMR SPECTRA AS WELL AS MASS SPECTRAL DATA. NEW ASPECTS OF THIS PROCEDURE AND FURTHER RESULTS ON PHOTOELECTRONIC PROPERTIES OF THE NEW COMPOUNDS WILL BE PRESENTED AND DISCUSSED.

آمار یکساله:  

بازدید 1155

دانلود 0
نشریه: 

آب و فاضلاب

اطلاعات دوره: 
  • سال: 

    1395
  • دوره: 

    27
  • شماره: 

    1 (مسلسل 101)
  • صفحات: 

    19-28
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    911
  • دانلود: 

    235
چکیده: 

بسیاری از رنگ های آلی مانند رنگ کاتیونی متیلن بلو به دلیل ساختار پیچیده آروماتیک و حلالیت بالا در آب، سمی، سرطانزا و غیر قابل تجزیه زیستی می باشند، لذا حذف آنها از پساب ضروری است. در این تحقیق، سیلیس نانوحفره sba-15 به روش هیدروترمال سنتز و سپس به روش پساسنتزی با گروه تک شاخه آمینی (NH2-sba-15) و دندریمرآمینی (MDA-sba-15) عامل دار شد. اثر اصلاح سطح بر روی کارایی جذب رنگ متیلن بلو در سیستم ناپیوسته بررسی شد. ویژگی نانو جاذب های سنتز شده با استفاده از آنالیزهای XRD، FT-IR، SEM و BET انجام شد. نتایج نشان داد که در شرایط یکسان، کارایی حذف متیلن بلو با استفاده از نانو جاذب MDA-sba-15، 37 میلی گرم بر گرم است که به ترتیب 2.6 و 3.3 برابر بیشتر از این کارایی برای جاذب های NH2-sba-15 و sba-15 است. فرایند جذب با استفاده از چهار مدل ایزوترمی لانگمیر، فروندلیچ، تمکین و دوبینین-رادکوویچ مدل سازی شد. همبستگی زیاد داده ها با مدل جذب لانگمیر بیانگر جذب تک لایه ای متیلن بلو بر روی MDA-sba-15 است. پارامترهای حاصل از ایزوترم تمکین نشان داد که روند جذب با MDA-sba-15 گرمازا است. کارایی بیش از 90 درصدی MDA-sba-15 نسبت به دو نانو جاذب دیگر در حذف رنگ متیلن بلو از محیط آبی نشان داد که می توان از آن به عنوان یک جاذب موثر در فرایند تصفیه استفاده نمود.

آمار یکساله:  

بازدید 911

دانلود 235 استناد 0 مرجع 0
گارگاه ها آموزشی
نویسندگان: 

اطلاعات دوره: 
  • سال: 

    2017
  • دوره: 

    35
  • شماره: 

    3
  • صفحات: 

    131-150
تعامل: 
  • استنادات: 

    315
  • بازدید: 

    7442
  • دانلود: 

    9195
کلیدواژه: 
چکیده: 

آمار یکساله:  

بازدید 7442

دانلود 9195 استناد 315 مرجع 0
اطلاعات دوره: 
  • سال: 

    2014
  • دوره: 

    0
  • شماره: 

    22
تعامل: 
  • بازدید: 

    1050
  • دانلود: 

    0
چکیده: 

IT IS WELL DOCUMENTED THAT COUMARINS ARE NOWADAYS AN IMPORTANT GROUP OF FLUORESCENT ORGANIC COMPOUNDS.THEY ARE USED AS OPTICAL BRIGHTENING AGENTS AND LASER DYES. THERE ARE SOME COUMARINS THAT MARKET FOR DYEING POLYESTER FIBRES, ALSO AS SUN PROTECTING AGENTS. LITERATURE SHOWS VARIOUS REPORTS ON SYNTHESIS AND BIOLOGICAL ACTIVITIES OF COUMARIN DERIVATIVES SUCH AS ANTI-TUMOUR, ANTI-CANCER, ANTI HIV, ALZIMER AND CARDIO PROTECTIVE AGENTS. [1] IN OUR RECENT INVESTIGATION HIGHLY FLUORESCENT COMPOUNDS WERE SYNTHESIZED BY AN EFFICIENT PROCEDURES [2, 3]. HERE IN, WE WISH TO REPORT NEWLY PREPARED AG-sba-15 AS CATALYST FOR THE SYNTHESIS OF SOME NEW AZO COUMARIN DYES.AZO SALICYLALDEHYDES1 CAN BE CONDENSED WITH CH-ACID COMPOUNDS SUCH AS ETHYLACETOACETATE 2 IN THE PRESENCE OF AG-sba-15 TO AFFORDED AZO COUMARIN DYES 3 IN HIGH YIELDS. THE PROCEDURE IS VERY SIMPLE AND NANO-CATALYST CAN BE EASILY RECOVERED FROM DYES AND USED FOR SEVERAL TIMES WITHOUT LOSING CATALYTIC ACTIVITY. NEW ASPECTS OF THIS PROCEDURE WILL BE PRESENTED AND DISCUSSED.

آمار یکساله:  

بازدید 1050

دانلود 0
نویسنده: 

BAHRAMI Z. | BADIEI A. | ATYABI F.

اطلاعات دوره: 
  • سال: 

    2013
  • دوره: 

    0
  • شماره: 

    16
تعامل: 
  • بازدید: 

    1470
  • دانلود: 

    0
کلیدواژه: 
چکیده: 

sba-15 NANORODS WITH HIGH SURFACE AREA (1010 M2G-1) WERE FUNCTIONALIZED BY POST GRAFTING METHOD WITH 3-AMINOPROPYLTRIETHOXYSILANE (APTES). THE PREPARED MATERIALS WERE USED AS NANOCARRIERS FOR ANTICANCER DRUG DELIVERY. GEMCITABINE WAS USED AS A REPRESENTATIVE ANTICANCER DRUG. THE ADSORPTION AND RELEASE PROPERTIES OF NON MODIFIED AND ORGANIC FUNCTIONALIZED MESOPOROUSSILICAS WERE INVESTIGATED. THESE MESOPOROUS MATERIALS WERE CHARACTERIZED BY SMALL ANGLE X RAY SCATTERING (SAXS), FOURIER TRANSFORM INFRARED SPECTROSCOPY (FTIR), SCANNING ELECTRON MICROSCOPY (SEM), TRANSMISSION ELECTRON MICROSCOPY (TEM), N2 ADSORPTION/DESORPTION ANALYSIS AND ULTRA VIOLET SPECTROSCOPY (UV).OUR STUDY REVEALED THAT THE SURFACE FUNCTIONALIZATION OF sba-15 NANORODS INCREASE THE INTERACTION OF THE SURFACE AND GEMCITABINE AND RESULTS IN THE LOADING ENHANCEMENT OF THE DRUG. IN ADDITION, THE DRUG RELEASE RATE OF MODIFIED SAMPLE IS PH DEPENDENT.

آمار یکساله:  

بازدید 1470

دانلود 0
strs
نویسندگان: 

SRINIVAS D. | SAIKIA L.

اطلاعات دوره: 
  • سال: 

    2008
  • دوره: 

    12
  • شماره: 

    -
  • صفحات: 

    0-0
تعامل: 
  • استنادات: 

    315
  • بازدید: 

    5883
  • دانلود: 

    9195
کلیدواژه: 
چکیده: 

آمار یکساله:  

بازدید 5883

دانلود 9195 استناد 315 مرجع 0
نویسنده: 

ABOLGHASEMI MIR MAHDI | SAVARE GHOLZAR

اطلاعات دوره: 
  • سال: 

    2015
  • دوره: 

    0
  • شماره: 

    21
تعامل: 
  • بازدید: 

    1260
  • دانلود: 

    0
کلیدواژه: 
چکیده: 

WE REPORT ON AN INORGANIC–ORGANIC HYBRID NANO-COMPOSITE THAT REPRESENTS A NOVEL KIND OF COATING FOR INSIDE NEEDLE CAPILLARY ADSORPTION TRAP (INCAT) OF POLYCYCLIC AROMATIC HYDROCARBONS (PAHS). POLYANILINE/sba-15 NANOCOMPOSITE WAS SYNTHESIZED VIA CHEMICAL POLYMERIZATION TECHNIQUE.....

آمار یکساله:  

بازدید 1260

دانلود 0
نویسنده: 

TAVAKOLI AMIR RASOUL | BADIEI ALIREZA

اطلاعات دوره: 
  • سال: 

    2014
  • دوره: 

    0
  • شماره: 

    16
تعامل: 
  • بازدید: 

    1260
  • دانلود: 

    0
کلیدواژه: 
چکیده: 

THE SENSITIVE AND SELECTIVE DETECTION OF ANIONS IS ESSENTIAL, CONSIDERING THEIR GROWING HAZARDS TO ENVIRONMENT AND HUMAN HEALTH. DURING THE PAST DECADE CONSIDERABLE EFFORTS HAS BEEN DEVOTED TO FLUORESCENCE SENSING OF ANIONS ON ACCOUNT OF EXCELLENT DETECTION ACCURACY AND FAST RESPONSE [1]. MESOPOROUS NANOSTRUCTURE WITH LARGE SURFACE AREA, PORE VOLUME, HYDROPHOBICITY, AND EASY RECYCLABILITY WOULD ALLOW THEM TO BE FAVORABLY USED AS A HETEROGENEOUS OPTICAL SENSORS FOR HIGHLY SENSITIVE DETECTION OF SPECIFIC GUESTS [2-4].IN THIS WORK WE DESIGNED AND SYNTHESIZED A NOVEL MESOPOROUS SYSTEM. AT FIRST, BENZOTHIAZOLE BASED LIGAND GRAFTED TO THE SILICA SURFACE BY POST SYNTHESIS METHOD, THE FINAL PRODUCT WAS OBTAINED VIA COMPLEXATION REACTION BETWEEN BENZOTHIAZOLE BASED LIGAND FUNCTIONALIZED sba-15,ZN2+ IONS AND ADDITIONAL 8-HYDOROXYQUINOLINE LIGAND THAT NAMED sba-BT-ZN-Q, CHARACTERIZATION OF THESE NANOSTRUCTURE WAS PERFORMED BY FT-IR, LOW ANGLE XRD, TEM, BET, TGA AND PL.THE FLUORESCENCE SPECTRUM OF THE sba-BT-ZN-Q SUSPENDED IN AQUEOUS MEDIUM SHOWED A SELECTIVE QUENCHING RESPONSES TOWARD DICHROMATE AND PERIODATE IONS IN COMPARISON OTHER ANIONS.

آمار یکساله:  

بازدید 1260

دانلود 0
نویسنده: 

SHAFIABADI M. | DASHTI A. | TAYEBI H.A.

اطلاعات دوره: 
  • سال: 

    2014
  • دوره: 

    0
  • شماره: 

    8
تعامل: 
  • بازدید: 

    1575
  • دانلود: 

    0
چکیده: 

SANTA BARBARA AMORPHOUS (sba-15) IS SIGNIFICANT MESOPOROUS SILICA WITH EXCLUSIVE AND IMPORTANT PROPERTIES OF HIGHLY ORDERED MESOPORES, HYDROTHERMALLY STABLE AND THICK WALL, PROFUSELY LARGE SURFACE AREA AND HUGE PORE VOLUME WHICH RENDER IT AS SORBENT FOR WIDE APPLICATIONS SUCH AS HEAVY METALS REMOVAL. IN THIS STUDY, SYNTHESIS AND PREPARATION OF sba-15 AND ITS NANOCOMPOSITE CONTAINING POLYPYRROLE (PPY) WAS DISCUSSED, AND THEIR CAPABILITY TO REMOVAL OF MERCURY (HG) FROM AQUEOUS SOLUTION WAS STUDIED. POLYPYRROLE WAS PREPARED BY CHEMICAL OXIDATIVE POLYMERIZATION OF PYRROLE USING FECL3 AS AN OXIDANT AND COATED ON sba-15 (PREPARED WITH SOL-GEL METHOD). THE REMOVAL OF HG WAS INVESTIGATED USING PPY, AND PPY/sba-15 NANOCOMPOSITE, RESPECTIVELY. THE PRODUCTS WERE INVESTIGATED IN TERMS OF MORPHOLOGY AND CHEMICAL STRUCTURE WITH TRANSMISSION ELECTRON MICROSCOPY (TEM) AND BET TEST, RESPECTIVELY. BATCH STUDIES WERE PERFORMED TO EVALUATE THE INFLUENCE OF VARIOUS EXPERIMENTAL PARAMETERS LIKE PH, ADSORBENT DOSAGE AND CONTACT TIME. OPTIMUM CONDITIONS FOR HG REMOVAL WERE FOUND TO BE PH=8, ADSORBENT DOSAGE OF 1 G/L AND EQUILIBRIUM TIME 60 MIN.

آمار یکساله:  

بازدید 1575

دانلود 0
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