36 research outputs found
The Effects of Different Types of Fly Ash on the Compressive Strength Properties of Briquettes
The aim of this study is to evaluate the effect of the different types of fly ash on the compressive strength properties of sintered briquettes. Thermal gravimetric (TG) analysis was carried out. The chemical composition and physical properties of the materials used were determined. Particle size distribution and microstructure elemental analyses of the materials used were carried out by a particle size analyzer (Mastersizer) and a scanning electron microscope (SEM-EDS).
Following the characterization of the materials, briquettes were prepared by sintering at different temperatures. Compressive strength test results of the briquette samples indicated that briquettes with a compressive strength value of 47.45 N/mm2 can be produced. The results obtained exceed the Turkish standard (TS EN 771-1) requirements (9.8–23.54 N/mm2). SEM-EDS results showed that briquette samples made with Tunçbilek (T) fly ash had a higher percentage of the glassy phase than the other briquette samples. Due to this microstructure, it results in higher compressive strength value
Topakların yapı ve dinamiklerinin incelenmesi
Tez (Doktora) -- Kırıkkale Üniversitesi78648
Investigation of structure and dynamics of cluste
YÖK Tez ID: 196776ÖZETTOPAKLARIN YAPI ve D NAM KLER N N NCELENMESAT Ş, MuratKırıkkale ÜniversitesiFen Bilimleri EnstitüsüFizik Anabilim Dalı, Doktora TeziDanışman : Prof. Dr. Hüseyin AKTAŞOrtak Danışman : Prof. Dr. Ziya B. GÜVENÇHaziran 2005, 136 sayfaBu çalışmada AgN ( 2 â?¤ N â?¤ 56 ) topaklarının en düşük enerjili kararlıyapıları, toplam enerjileri, atom başına bağ enerjileri, birinci ve ikinci farkenerjileri, izomer oluşma olasılıkları, atom başına ortalama bağ uzunlukları veatom başına ortalama komşu sayıları Voter-Chen versiyon Embedded AtomPotansiyeli kullanılarak Moleküler Dinamik, Monte Carlo ve Genetik Algoritmayöntemleri ile incelendi. Ayrıca, AgN ( 5 â?¤ N â?¤ 56 ) topaklarının erimedinamikleri tüm sistem ve her bir atom için bağ uzunluklarının kare ortalamakareköklerinin değişimi, özısı, uzun ve kısa zaman ortalamalı komşuluksayıları ve kısa zaman ortalamalı sıcaklık grafikleri yardımıyla incelendi.Sonuçlar literatürdeki uygun çalışmalarla karşılaştırıldı.Anahtar Kelimeler : Topaklar, Gümüş, Ag, MD, MC, GA, Hamming'inPredictor Corrector Algoritması, Embedded Atom Potansiyeli, LBFGS,Termal Soğutma.IABSTRACTINVESTIGATION OF STRUCTURE AND DYNAMICS OF CLUSTERSAT Ş, MuratKırıkkale UniversityGraduate School Of Natural and Applied SciencesDeparment of Physics, Ph. D. ThesisSupervisor : Prof. Dr. Hüseyin AKTAŞCo-visor : Prof. Dr. Ziya B. GÜVENÇJUNE 2005, 136 pagesIn this study, the most stable structures, total energies, bindingenergies per atom, the first and the second energy differences, and isomerforming probability of AgN ( 2 â?¤ N â?¤ 56 ) clusters were investigated with usingMolecular Dynamics, Monte Carlo and Genetic Algorithm methods based onVoter-Chen version of Embedded Atom Potential. In addition, meltingdynamics of AgN ( 5 â?¤ N â?¤ 56 ) clusters were described in terms of atomresolved root-mean-square bond-length fluctuations, coordination numbers,specific heats and, short-time averaged temperatures. Some of thesediagnostic tools are also used for the whole clusters. Results are comparedto the relevant literatures.Key Words: Cluster, Silver, Ag, MD, MC, GA, Hamming?s PredictorCorrector Algorithm, Embedded Atom Potential, LBFGS, Thermal Quenching.I
The theoretical and experimental investigation of the vibrational spectra of 4-tolylboronic acid molecules
Bu çalışmamızda 4-Tolilboronik asit molekülünün yapısal ve titreşimsel özellikleri deneysel ve teorik olarak incelenmiştir. Molekülün FT-IR spektrumu 4000-650 cm-1 ; FT-Raman spektrumu 3500-5 cm-1 aralığında kaydedilmiştir. Teorik ve deneysel IR ve Raman spektrumlarının grafikleri çizildi. Gaussian 09 programıyla 6-311++G(d,p) temel setinde B3LYP teori düzeyinde molekülün bağ açıları, bağ uzunlukları, dihedral açıları ve titreşim frekansları hesaplandı ve deneysel değerlerle karşılaştırıldı. Titreşim modlarının işaretlenmesi için toplam enerji dağılımı (TED) VEDA programı kullanılarak hesaplandı. Bu çalışma sonucunda incelediğimiz molekülün geometrik, fiziksel ve kimyasal özelliklerinin anlaşılmasına kapı açılmıştır. Hesaplanan teorik ve deneysel verilerin birbiri ile uyum içerisinde olduğu gözlendi.Molecular structure and vibration frequency analysis of 4-Tolylboronic acid were investigated in our study. The molecule was worked an experimentally and theoretically. The FT-IR spectrum of molecule was saved between 4000 cm-1 and 650 cm-1, the FT-Raman spectrum was saved between 3500 cm-1 and 5 cm-1. Theoretical and experimental IR and Raman spectra were drawed. Bond lenghts, bond angles, dihedral angles and vibration frequencies were calculated on the 6-311++G(d,p) basic set, density function theory and B3LYP theory by Gaussian 09 program and their values were compared with experimental values. Total energy distributions (TED) were calculated to find the vibration modes by using VEDA program. In the end of the study, we gain informations about the geometric, physical and chemical properties of the molecule. The calculated theorical results are agreed with the experimental datas
The theoretical and experimental investigation of the vibrational spectra of 1h-benzi?mi?dazole-2-carboxylic acid molecule
Bu çalışmamızda 1H-Benzimidazole-2-Karboksilik Asit molekülünün yapısal ve titreşimsel özellikleri deneysel ve teorik olarak incelenmiştir. Moleküllerin FT-IR ve FT-Raman spektrumları ayrı ayrı 4000-650 ve 3500-50 cm-1 aralığında kaydedildi. Teorik ve deneysel IR ve Raman spektrumları çizildi. Gaussian 03 programıyla 6-31++G(2d,2p) temel setinde B3LYP teori düzeyinde molekülün bağ açıları, bağ uzunlukları, dihedral açıları ve titreşim frekansları hesaplandı ve deneysel değerlerle karşılaştırıldı. Titreşim modlarının işaretlenmesi için toplam enerji dağılımı (TED) SQM programı kullanılarak hesaplandı. Bu çalışma sonucunda incelediğimiz molekülün geometrik, fiziksel ve kimyasal özelliklerinin anlaşılmasına kapı açılmıştır. Hesaplanan teorik ve deneysel verilerin birbiri ile uyum içerisinde olduğu gözlenmiştir.Molecular structure and vibration frequency analysis of 1H-Benzimidazole-2-carboxylic acid were investigated in our study. The molecule was worked as theoretically and experimentally. The FT-IR and FT-Raman spectrums of molecule were recorded in the 4000 - 650 and 3500 - 50 cm-1 range, respectively. Theoretical and experimental IR and Raman spectra were illustrated. Bond lenghts, bond angles dihedral angles and vibration frequencies were calculated with density function theory and B3LYP method using the 6-31++G(2d,2p) basis set, by Gaussian 03 program and their values were compared with experimental values. The assignments of the normal vibrational modes were obtained using the total energy distribution (TED) by SQM program. We concluded that the calculated and observed results on the geometric, physical and chemical properties were consistent with each other. The calculated theorical results are agreed with the experimental datas
The theoretical and experimental investigation of the vibrational spectra of 2-phenylbenzimidazole acid molecule
Bu çalışmamızda 2-Fenilbenzimidazol asit molekülünün yapısal ve titreşimsel özellikleri deneysel ve teorik olarak incelenmiştir. Moleküllerin FT-IR spektrumları 4000-650 cm-1; FT-Raman spektrumları 3500-5 cm-1 aralığında kaydedildi. Teorik ve deneysel IR ve Raman spektrumları çizildi. Gaussian 09 programıyla 6-311++G(d,p) temel setinde B3LYP teori düzeyinde molekülün bağ açıları, bağ uzunlukları, dihedral açıları ve titreşim frekansları hesaplandı ve deneysel değerlerle karşılaştırıldı. Titreşim modlarının işaretlenmesi için toplam enerji dağılımı (TED) VEDA programı kullanılarak hesaplandı. Bu çalışma sonucunda incelediğimiz molekülün geometrik, fiziksel ve kimyasal özelliklerinin anlaşılmasına kapı açılmıştır. Hesaplanan teorik ve deneysel verilerin birbiri ile uyum içerisinde olduğu gözlenmiştir.Molecular structure and vibration frequency analysis of 2-phenylbenzimidazole acid were investigated in our study. The molecule was worked as theoretically and experimentally. The FT-IR spectrum of molecule was saved between 4000 cm-1 and 650 cm-1, the FT-Raman spectrum was saved between 3500 cm-1 and 5 cm-1. Theoretical and experimental IR and Raman spectra were drawed. Bond lenghts, bond angles dihedral angles and vibration frequencies were calculated on the 6-311++G(d,p) basic set, density function theory and B3LYP theory by Gaussian 09 program and their values were compared with experimental values. Total energy distribution (TED) were calculated to find the vibration modes by using VEDA program. In the end of the study, we gain informations about the geometric, physical and chemical properties of the molecule. The calculated theorical results are agreed with the experimental datas
The theoretical and experimental investigation of the vibrational spectra of 4-(Methylsulfanyl)phenylboronic acid molecule
Bu çalışmada 4-(metilsülfanil)fenilboronik asit molekülünün yapı ve titreşim frekansları analizi yapıldı. En düşük enerjili konformasyon tespit edildi. Bu yapının geometrik parametreleri ve titreşim frekansları Gaussian 09 programı ile hesaplandı. FT-IR spektrumları 4000-650 cm-1; FT-Raman spektrumları 3500-5 cm-1 aralığında deneysel ve teorik olarak kaydedildi. Teorik ve deneysel IR ve Raman spektrumları çizildi. Gaussian 09 programıyla 6-311++G(d,p) temel setinde yoğunluk fonksiyon teorisi içerisinde B3LYP teori düzeylerinde molekülün bağ açıları, bağ uzunlukları, dihedral açıları ve titreşim frekansları hesaplandı ve deneysel değerlerle karşılaştırıldı. Titreşim modlarının işaretlenmesi için toplam enerji dağılımı (TED) VEDA programı kullanılarak hesaplandı. Çalışma sonucunda incelediğimiz molekülün, fiziksel ve kimyasal özelliklerinin anlaşılmasına katkıda bulunulmaya çalışılmıştır. Aynı zamanda hesaplanan teorik ve deneysel verilerin birbiri ile uyum içerisinde olduğu gözlenmiştir.In this study, molecular structure and vibration frequency analysis of 4-(methylsulfanyl)phenylboronic acid were investigated. The lowest energy conformer was defined. The geometrical parameters and vibrational frequencies of this conformer were calculated by using Gaussian 09 software. The FT-IR spectrum of molecule was saved between 4000 cm-1and 650 cm-1, the FT-Raman spectrum was saved between 3500 cm-1 and 5 cm-1. Theoretical and experimental IR and Raman spectra were drawed. Bond lenghts, bond angles, dihedral angles and vibration frequencies were calculated on the 6-311++G(d,p) basic set, density function theory and B3LYP theory by Gaussian 09 program and their values were compared with experimental values. Total energy distributions (TED) were calculated to find the vibration modes by using VEDA program. In the end of the study, we gain in formations about the geometric, physical and chemical properties of the molecule. The calculated theorical results are agreed with the experimental datas
Structure and dynamical properties of Au-N, N=12-14 clusters: Molecular dynamics simulation
ATIS, Murat/0000-0003-4429-6897WOS: 000229549400007Using molecular dynamics and thermal quenching methods on the basis of Voter-Chen version of the embedded-atom method, we have studied the melting behavior of Au-N (N = 12, 13, 14) clusters. This behavior is described in terms of overall and atom resolved root-mean-square bond-length fluctuations, specific-heat, short- and long-time average coordination numbers of each atom and short-time average temperatures of the clusters. The isomer sampling probabilities are obtained from the thermal quenching of the molten clusters, and their energy-spectrum widths are investigated. Phase change of a cluster takes place with the collective and simultaneous motion of all the atoms
Density Functional Study of Physical and Chemical Properties of Nano Size Boron Clusters: B-n (n=13-20)
Molecular dynamics simulation of melting behaviour of small gold clusters: Au-N (N=12-14)
We have investigated the melting behaviour of AuN (N = 12 - 14) clusters by means of molecular dynamics simulation on the basis of the Voter - Chen version of the embedded-atom method. The melting behaviour of the clusters is described in terms of short-time average temperatures and atomic coordination numbers of the clusters. Results have shown that during the melting process, the phase changes occur as a collective and simultaneous motion of all the atoms in a very short-time interval. Furthermore the Au-14 cluster presents a two-stage melting behaviour which is different from those of the Au-12 and Au-13 clusters. The isomer sampling probabilities are obtained from the thermal quenching of the molten clusters, and their energy-spectrum widths are investigated. The results of the isomer forming probabilities showed that the global minimum structures of these clusters are not always the most probable ones to be formed in the experiments.</p