Search results for: molecular interfacial layer

Authors: A. Nazeri, R. Ziaie Moayed, H. Ghiasinejad

Abstract:

The present research has been performed to investigate the effect of base course application on load-settlement characteristics of sandy subgrade using plate load test. The main parameter investigated in this study was the subgrade reaction coefficient. The model tests were conducted in a 1.35 m long, 1 m wide, and 1 m deep steel test box of Imam Khomeini International University (IKIU Calibration Chamber). The base courses used in this research were in three different thicknesses of 15 cm, 20 cm, and 30 cm. The test results indicated that in the case of using base course over loose sandy subgrade, the values of subgrade reaction coefficient can be increased from 7  to 132 , 224 , and 396  in presence of 15 cm, 20 cm, and 30 cm base course, respectively.

Keywords: modulus of subgrade reaction, plate load test, base course, sandy subgrade

Procedia PDF Downloads 247

Authors: S. Ghammamy, M. Mirzaabdollahiha

Abstract:

Quantum mechanical calculations of energies, geometries, and vibrational wavenumbers of fluorous 1,3-dion compounds are carried out using density functional theory (DFT/B3LYP) method with LANL2DZ basis sets. The calculated HOMO and LUMO energies show that charge transfer occurs in the molecules. The thermodynamic functions of fluorous 1,3-dion compounds have been performed at B3LYP/LANL2DZ basis sets. The theoretical spectrograms for F NMR spectra of fluorous 1,3-dion compounds have also been constructed. The F NMR nuclear shieldings of fluoride ligands in fluorous 1,3-dion compounds have been studied quantum chemical.

Keywords: density function theory, natural bond orbital, HOMO, LOMO, fluorous

Procedia PDF Downloads 390

Authors: N. F. M. Mokhtar, N. Z. A. Hamid

Abstract:

This paper reports an analytical investigation of the stability and thermal convection in a horizontal anisotropic porous medium in the presence of Coriolis force and magnetic field. The Darcy model is used in the momentum equation and Boussinesq approximation is considered for the density variation of the porous medium. The upper and lower boundaries of the porous medium are assumed to be conducting to temperature perturbation and we used first order Chebyshev polynomial Tau method to solve the resulting eigenvalue problem. Analytical solution is obtained for the case of stationary convection. It is found that the porous layer system becomes unstable when the mechanical anisotropy parameter elevated and increasing the Coriolis force and magnetic field help to stabilize the anisotropy porous medium.

Keywords: anisotropic, Chebyshev tau method, Coriolis force, Magnetic field

Procedia PDF Downloads 214

Authors: Sina Ranjbar, Masakiyo Tsunoda, Mikihiko Oogane, Yasuo Ando

Abstract:

We systematically investigated the exchange anisotropy for ferromagnetic Co70Fe30 and antiferromagnetic PtMn bilayer films. We focused on the relevance between the exchange bias and the composition of the Ptₓ Mn₁₋ₓ (14 < x < 22 and 45 < x < 56 at %) films, and we successfully optimized the composition. The crystal structure of the Ptₓ Mn₁₋ₓ films was FCC for 14 < x < 22 at % and FCT for 45 < x < 56 at % after annealing at 370 ◦C for 6 hours. The unidirectional anisotropy constant (Jₖ) for fcc-Pt₁₅Mn₈₅ (20 nm) and fct-Pt₄₈Mn₅₂ (20 nm) prepared under optimum conditions in composition were 0.16 and 0.20 erg/cm², respectively. Both Pt₁₅Mn₈₅ and Pt₄₈Mn₅₂ films showed a larger unidirectional anisotropy constant (Jₖ) than in other reports. They also showed a flatter surface than that of other antiferromagnetic materials. The obtained PtMn films with a large exchange anisotropy and slight roughness are useful as an antiferromagnetic layer in spintronic applications.

Keywords: antiferromagnetic material, PtMn thin film, exchange anisotropy, composition dependence

Procedia PDF Downloads 261

Authors: Izza Hidaya, Korichi Mourad

Abstract:

Solvent extraction is an affective method for reduction of aromatic content of lube oil. Frequently with phenol, furfural, NMP(N-methyl pyrrolidone). The solvent power and selectivity can be further increased by using surfactant as additive which facilitate phase separation and to increase raffinate yield. The aromatics in lube oil were extracted at different temperatures (ranging from 333.15 to 343.15K) and different concentration of surfactant (ranging from 0.01 to 0.1% wt).The extraction temperature and the amount of sulfate lauryl éther de sodium In phenoll were investigated systematically in order to determine their optimum values. The amounts of aromatic, paraffinic and naphthenic compounds were determined using ASTM standards by measuring refractive index (RI), viscosity, molecular weight and sulfur content. It was found that using 0,01%wt. surfactant at 343.15K yields the optimum extraction conditions.

Keywords: extraction, lubricating oil, aromatics, hydrocarbons

Procedia PDF Downloads 521

Authors: Sofiane Bourchak, Sébastien Bridier

Abstract:

The objective of this study is to show how to calculate and map solar energy’s quantity (instantaneous and accumulated global solar radiation during the year) available on roofs in the city Aix-en-Provence which has a population of 140,000 inhabitants. The result is a geographic information system (GIS) layer, which represents hourly and monthly the production of solar energy on roofs throughout the year. Solar energy professionals can use it to optimize implementations and to size energy production systems. The results are presented as a set of maps, tables and histograms in order to determine the most effective costs in Aix-en-Provence in terms of photovoltaic power (electricity) and thermal power (hot water).

Keywords: geographic information system, photovoltaic, thermal, solar potential, solar radiation

Procedia PDF Downloads 436

Authors: H. Yousefnia, A. Golabi Dezfuli, S. Zolghadri, M. Hosntalab

Abstract:

Peptide receptor radionuclide therapy is nowadays used for the treatment of various abnormalities with somatostatin receptors. In this study, 166Ho-DOTATOC was prepared and the best conditions for its radiolabeling was obtained. For this purpose, a certain of DOTATOC was added to a vial containing 166Ho. various experiments by varying ligand concentration, pH, temperature and time were performed to determine the best conditions. Radiochemical purity of the complex was assessed by instant thin layer chromatography method utilizing 0.9% NaCl as the mobile phase. 166Ho-DOTATOC was prepared with radiochemical purity of higher than 95% at the optimized condition (pH=4, temperature: 95° C, time:30 min). In 0.9% NaCl, free Ho cation was developed at Rf of 0.8 while the complex was remained at the front of the paper.

Keywords: Ho-166, neuroendocrine, octreotide, quality control

Procedia PDF Downloads 386

Authors: Jackson Andreas Theo Pola, Leksono Mucharam, Hari Oetomo, Budi Susanto, Wisnu Nugraha

Abstract:

About half of the world oil reserves are located in carbonate reservoirs, where 65% of the total carbonate reservoirs are oil wet and 12% intermediate wet [1]. Oil recovery in oil wet or mixed wet carbonate reservoirs can be increased by dissolving surfactant to injected water to change the rock wettability from oil wet to more water wet. The Wakamuk Field operated by PetroChina International (Bermuda) Ltd. and PT. Pertamina EP in Papua, produces from main reservoir of Miocene Kais Limestone. First production commenced on August, 2004 and the peak field production of 1456 BOPD occurred in August, 2010. It was found that is a complex reservoir system and until 2014 cumulative oil production was 2.07 MMBO, less than 9% of OOIP. This performance is indicative of presence of secondary porosity, other than matrix porosity which is of low average porosity 13% and permeability less than 7 mD. Implementing chemical EOR in this case is the best way to increase oil production. However, the selected chemical must be able to lower the interfacial tension (IFT), reduce oil viscosity, and alter the wettability; thus a special chemical treatment named SeMAR has been proposed. Numerous laboratory tests such as phase behavior test, core compatibility test, mixture viscosity, contact angle measurement, IFT, imbibitions test and core flooding were conducted on Wakamuk field samples. Based on the spontaneous imbibitions results for Wakamuk field core, formulation of SeMAR with compositional S12A gave oil recovery 43.94% at 1wt% concentration and maximum percentage of oil recovery 87.3% at 3wt% concentration respectively. In addition, the results for first scenario of core flooding test gave oil recovery 60.32% at 1 wt% concentration S12A and the second scenario gave 96.78% of oil recovery at concentration 3 wt% respectively. The soaking time of chemicals has a significant effect on the recovery and higher chemical concentrations affect larger areas for wettability and therefore, higher oil recovery. The chemical that gives best overall results from laboratory tests study will also be a consideration for Huff and Puff injections trial (pilot project) for increasing oil recovery from Wakamuk Field

Keywords: Wakamuk field, chemical treatment, oil recovery, viscosity

Procedia PDF Downloads 693

Authors: Arabi Nour El Houda, Iratni Aicha, Talaighil Razika, Bruno Capoen, Mohamed Bouazaoui

Abstract:

TiO2 thin films have been prepared by the sol-gel dip-coating technique in order to elaborate antireflective thin films for monocrystalline silicon (mono-Si). The titanium isopropoxyde was chosen as a precursor with hydrochloric acid as a catalyser for preparing a stable solution. The optical properties have been tailored with varying the solution concentration, the withdrawn speed, and the heat-treatment. We showed that using a TiO2 single layer with 64.5 nm in thickness, heat-treated at 450°C or 300°C reduces the mono-Si reflection at a level lower than 3% over the broadband spectral do mains [669-834] nm and [786-1006] nm respectively. Those latter performances are similar to the ones obtained with double layers of low and high refractive index glasses respectively.

Keywords: thin film, dip-coating, mono-crystalline silicon, titanium oxide

Procedia PDF Downloads 438

Authors: Mounir Baccar, Imen Jmal

Abstract:

Because of the rise in energy costs, thermal storage systems designed for the heating and cooling of buildings are becoming increasingly important. Energy storage can not only reduce the time or rate mismatch between energy supply and demand but also plays an important role in energy conservation. One of the most preferable storage techniques is the Latent Heat Thermal Energy Storage (LHTES) by Phase Change Materials (PCM) due to its important energy storage density and isothermal storage process. This paper presents a numerical study of the solidification of a PCM (paraffin RT27) in a rectangular thermal storage exchanger for air conditioning systems taking into account the presence of natural convection. Resolution of continuity, momentum and thermal energy equations are treated by the finite volume method. The main objective of this numerical approach is to study the effect of natural convection on the PCM solidification time and the impact of fins number on heat transfer enhancement. It also aims at investigating the temporal evolution of PCM solidification, as well as the longitudinal profiles of the HTF circling in the duct. The present research undertakes the study of two cases: the first one treats the solidification of PCM in a PCM-air heat exchanger without fins, while the second focuses on the solidification of PCM in a heat exchanger of the same type with the addition of fins (3 fins, 5 fins, and 9 fins). Without fins, the stratification of the PCM from colder to hotter during the heat transfer process has been noted. This behavior prevents the formation of thermo-convective cells in PCM area and then makes transferring almost conductive. In the presence of fins, energy extraction from PCM to airflow occurs at a faster rate, which contributes to the reduction of the discharging time and the increase of the outlet air temperature (HTF). However, for a great number of fins (9 fins), the enhancement of the solidification process is not significant because of the effect of confinement of PCM liquid spaces for the development of thermo-convective flow. Hence, it can be concluded that the effect of natural convection is not very significant for a high number of fins. In the optimum case, using 3 fins, the increasing temperature of the HTF exceeds approximately 10°C during the first 30 minutes. When solidification progresses from the surfaces of the PCM-container and propagates to the central liquid phase, an insulating layer will be created in the vicinity of the container surfaces and the fins, causing a low heat exchange rate between PCM and air. As the solid PCM layer gets thicker, a progressive regression of the field of movements is induced in the liquid phase, thus leading to the inhibition of heat extraction process. After about 2 hours, 68% of the PCM became solid, and heat transfer was almost dominated by conduction mechanism.

Keywords: heat transfer enhancement, front solidification, PCM, natural convection

Procedia PDF Downloads 187

Authors: Anjali Roy, Mirza S. Baig

Abstract:

Atherosclerosis is a chronic inflammatory disease characterized by the formation of lipid rich plaque enriched with necrotic core, modified lipid accumulation, smooth muscle cells, endothelial cells, leucocytes and macrophages. Macrophage foam cells play a critical role in the occurrence and development of inflammatory atherosclerotic plaque. Foam cells are the fat-laden macrophages in the initial stage atherosclerotic lesion formation. Foam cells are an indication of plaque build-up, or atherosclerosis, which is commonly associated with increased risk of heart attack and stroke as a result of arterial narrowing and hardening. The mechanisms that drive atherosclerotic plaque progression remain largely unknown. Dissecting the molecular mechanism involved in process of macrophage foam cell formation will help to develop therapeutic interventions for atherosclerosis. To investigate the mechanism, we studied the role of nitric oxide synthase 1(NOS1)-mediated nitric oxide (NO) on low-density lipoprotein (LDL) uptake by bone marrow derived macrophages (BMDM). Using confocal microscopy, we found that incubation of macrophages with NOS1 inhibitor, TRIM (1-(2-Trifluoromethylphenyl) imidazole) or L-NAME (N omega-nitro-L-arginine methyl ester) prior to LDL treatment significantly reduces the LDL uptake by BMDM. Further, addition of NO donor (DEA NONOate) in NOS1 inhibitor treated macrophages recovers the LDL uptake. Our data strongly suggest that NOS1 derived NO regulates LDL uptake by macrophages and foam cell formation. Moreover, we also checked proinflammatory cytokine mRNA expression through real time PCR in BMDM treated with LDL and copper oxidized LDL (OxLDL) in presences and absences of inhibitor. Normal LDL does not evoke cytokine expression whereas OxLDL induced proinflammatory cytokine expression which significantly reduced in presences of NOS1 inhibitor. Rapid NOS-1-derived NO and its stable derivative formation act as signaling agents for inducible NOS-2 expression in endothelial cells, leading to endothelial vascular wall lining disruption and dysfunctioning. This study highlights the role of NOS1 as critical players of foam cell formation and would reveal much about the key molecular proteins involved in atherosclerosis. Thus, targeting NOS1 would be a useful strategy in reducing LDL uptake by macrophages at early stage of disease and hence dampening the atherosclerosis progression.

Keywords: atherosclerosis, NOS1, inflammation, oxidized LDL

Procedia PDF Downloads 127

Authors: Elabed Saud

Abstract:

This paper introduces the new ability of Artificial Neural Networks (ANNs) in estimating speed and controlling the separately excited DC motor. The neural control scheme consists of two parts. One is the neural estimator which is used to estimate the motor speed. The other is the neural controller which is used to generate a control signal for a converter. These two neutrals are training by Levenberg-Marquardt back-propagation algorithm. ANNs are the standard three layers feed-forward neural network with sigmoid activation functions in the input and hidden layers and purelin in the output layer. Simulation results are presented to demonstrate the effectiveness of this neural and advantage of the control system DC motor with ANNs in comparison with the conventional scheme without ANNs.

Keywords: Artificial Neural Network (ANNs), excited DC motor, convenional controller, speed Controller

Procedia PDF Downloads 726

Authors: Hsiang-Ru Lin

Abstract:

Cholesterol plays an essential role in the regulation of the progression of numerous important diseases including atherosclerosis and Alzheimer disease so the generation of suitable cholesterol-lowering reagents is urgent to develop. Liver X receptor (LXR) is a ligand-activated transcription factor whose natural ligands are cholesterols, oxysterols and glucose. Once being activated, LXR can transactivate the transcription action of various genes including CYP7A1, ABCA1, and SREBP1c, involved in the lipid metabolism, glucose metabolism and inflammatory pathway. Essentially, the upregulation of ABCA1 facilitates cholesterol efflux from the cells and attenuates the production of beta-amyloid (ABeta) 42 in brain so LXR is a promising target to develop the cholesterol-lowering reagents and preventative treatment of Alzheimer disease. Engelhardia roxburghiana is a deciduous tree growing in India, China, and Taiwan. However, its chemical composition is only reported to exhibit antitubercular and anti-inflammatory effects. In this study, four compounds, engelheptanoxides A, C, engelhardiol A, and B isolated from the root of Engelhardia roxburghiana were evaluated for their agonistic activity against LXR by the transient transfection reporter assays in the HepG2 cells. Furthermore, their interactive modes with LXR ligand binding pocket were generated by molecular modeling programs. By using the cell-based biological assays, engelheptanoxides A, C, engelhardiol A, and B showing no cytotoxic effect against the proliferation of HepG2 cells, exerted obvious LXR agonistic effects with similar activity as T0901317, a novel synthetic LXR agonist. Further modeling studies including docking and SAR (structure-activity relationship) showed that these compounds can locate in LXR ligand binding pocket in the similar manner as T0901317. Thus, LXR is one of nuclear receptors targeted by pharmaceutical industry for developing treatments of Alzheimer and atherosclerosis diseases. Importantly, the cell-based assays, together with molecular modeling studies suggesting a plausible binding mode, demonstrate that engelheptanoxides A, C, engelhardiol A, and B function as LXR agonists. This is the first report to demonstrate that the extract of Engelhardia roxburghiana contains LXR agonists. As such, these active components of Engelhardia roxburghiana or subsequent analogs may show important therapeutic effects through selective modulation of the LXR pathway.

Keywords: Liver X receptor (LXR), Engelhardia roxburghiana, CYP7A1, ABCA1, SREBP1c, HepG2 cells

Procedia PDF Downloads 420

Authors: Edina Koch, Károly Gombás, Márton Maller

Abstract:

The Little Plain is located along the Danube river, and this area is a “hotbed” of sand boil formation. This is due to the combination of a 100-250 m thick gravel layer beneath the Little Plain with a relatively thin blanket of poor soil spreading the gravel with variable thickness. Sand boils have a tradition and history in this area. It was possible to know which sand boil started and stopped working at what water level, and some of them even have names. The authors present a 2D finite element model of groundwater flow through a selected cross-section of the Danube river, which observed activation of piping phenomena during the 2013 flood event. Soil parametrization is based on a complex site investigation program conducted along the Danube River in the Little Plain.

Keywords: site characterization, groundwater flow, numerical modeling, sand boil

Procedia PDF Downloads 95

Authors: Latef M. Ali, Farah A. Abed

Abstract:

In this paper, the effect of the Barium fluoride (BaF2) layer on the absorption efficiency of GaAs/InAs nanowire solar cells was investigated using the finite difference time domain (FDTD) method. By inserting the BaF2 as antireflection with the dominant size of 10 nm to fill the space between the shells of wires on the Si (111) substrate. The absorption is significantly improved due to the strong reabsorption of light reflected at the shells and compared with the reference cells. The present simulation leads to a higher absorption efficiency (Qabs) and reaches a value of 97%, and the external quantum efficiencies (EQEs) above 92% are observed. The current density (Jsc) increases by 0.22 mA/cm2 and the open-circuit voltage (Voc) is enhanced by 0.11 mV.

Keywords: nanowire solar cells, absorption efficiency, photovoltaic, band structures, fdtd simulation

Procedia PDF Downloads 72

Authors: Arundhathi S., Poongodi R.

Abstract:

Tumor-infiltrating lymphocytes (TILs) are indicative of the local immune response against tumor proliferation and metastasis. Emerging as a significant marker of immune reactivity, TILs are utilized to evaluate prognostic outcomes across various malignancies, including colon, ovarian, lung, bladder, and breast cancers. In breast cancer (BC), TILs are particularly relevant for assessing tumor response to therapy in both adjuvant and neoadjuvant settings, with a prominent role in triple-negative breast cancer (TNBC), where they have been associated with improved outcomes. As such, TILs are recognized as an independent marker of favorable prognosis in several tumor types, underscoring their potential as a tool in personalized cancer therapy.

Keywords: breast cancer, intratumoral TIL, stromal TIL, tumor infiltrating lymphocytes

Procedia PDF Downloads 8

Authors: Daseul Lee, Jeong Jun Lee, Ok-Sang Jung

Abstract:

Self-assembly of a series of ZnX2 (X- = Cl-, Br-, and I-) with 2,3-bis(4’-nicotinamidephenoxy)naphthalene (L) as a new bidentate pyridyl-donor ligand yields systematic metallacyclodimeric unit, [ZnX2L]2. The supramolecule constitutes a characteristically stacked forming both 1D suprachannels and cages. Weak C-H⋯π and inter-digitated π⋯π interactions are main driving forces in the formation of both suprachannels and cages. The slightly different features between the suprachannel and cage have been investigated by 1H NMR and TG analysis, which solvent quantitatively exchange within only suprachannels. Photo-unstable CH2I2 molecules are stabilized via capturing within suprachannels, which is monitored by UV-Vis spectroscopy. Furthermore, the photoluminescence intensity, from the chromophore naphthyl moiety of [ZnCl2L]2, gradually decreases with the addition of CH2I2. And washing off the CH2I2 by dichloromethane returned the PL intensity back to its approximately original signal.

Keywords: metallacyclodimer, suprachannel, π⋯π interaction, molecular recognition

Procedia PDF Downloads 322

Authors: M. Gowri, E. K. Girija, V. Ganesh

Abstract:

Background and Significance: Among the dental infections, inflammation and infection of the root canal are common among all age groups. Currently, the management of root canal infections involves cleaning the canal with powerful irrigants followed by intracanal medicament application. Though these treatments have been in vogue for a long time, root canal failures do occur. Treatment for root canal infections is limited due to the anatomical complexity in terms of small micrometer volumes and poor penetration of drugs. Thus, infections of the root canal seem to be a challenge that demands development of new agents that can eradicate C. albicans. Methodology: In the present study, we synthesized and screened silver-curcumin nanoparticle against Candida albicans. Detailed molecular studies were carried out with silver-curcumin nanoparticle on C. albicans pathogenicity. Morphological cell damage and antibiofilm activity of silver-curcumin nanoparticle on C. albicans was studied using scanning electron microscopy (SEM). Biochemical evidence for membrane damage was studied using flow cytometry. Further, the antifungal activity of silver-curcumin nanoparticle was evaluated in an ex vivo dentinal tubule infection model. Results: Screening data showed that silver-curcumin nanoparticle was active against C. albicans. Silver-curcumin nanoparticle exerted time kill effect and post antifungal effect. When used in combination with fluconazole or nystatin, silver-curcumin nanoparticle revealed a minimum inhibitory concentration (MIC) decrease for both drugs used. In-depth molecular studies with silver-curcumin nanoparticle on C. albicans showed that silver-curcumin nanoparticle inhibited yeast to hyphae (Y-H) conversion. Further, SEM images of C. albicans showed that silver-curcumin nanoparticle caused membrane damage and inhibited biofilm formation. Biochemical evidence for membrane damage was confirmed by increased propidium iodide (PI) uptake in flow cytometry. Further, the antifungal activity of silver-curcumin nanoparticle was evaluated in an ex vivo dentinal tubule infection model, which mimics human tooth root canal infection. Confocal laser scanning microscopy studies showed eradication of C. albicans and reduction in colony forming unit (CFU) after 24 h treatment in the infected tooth samples in this model. Conclusion: The results of this study can pave the way for developing new antifungal agents with well deciphered mechanisms of action and can be a promising antifungal agent or medicament against root canal infection.

Keywords: C. albicans, ex vivo dentine model, inhibition of biofilm formation, root canal infection, yeast to hyphae conversion inhibition

Procedia PDF Downloads 208

Authors: Amir Razmjou, Elika Karbassi Yazdi

Abstract:

Several direct lithium extraction (DLE) technologies have been developed for Li extraction from different brines. Although laboratory studies showed that they can technically recover Li to 90%, challenges still remain in developing a sustainable process that can serve as a foundation for the lithium dependent low-carbon economy. There is a continuing quest for DLE technologies that do not need extensive pre-treatments, fewer materials, and have simplified extraction processes with high Li selectivity. Here, an overview of DLE technologies will be provided with an emphasis on the basic principles of the materials’ design for the development of membranes with nanochannels and nanopores with Li ion selectivity. We have used a variety of building blocks such as nano-clay, organic frameworks, Graphene/oxide, MXene, etc., to fabricate the membranes. Molecular dynamic simulation (MD) and density functional theory (DFT) were used to reveal new mechanisms by which high Li selectivity was obtained.

Keywords: lithium recovery, membrane, lithium selectivity, decarbonization

Procedia PDF Downloads 112

Authors: Bandar Ali Al-Asbahi, Mohammad Hafizuddin Haji Jumali

Abstract:

Forster energy transfer between poly (9,9'-di-n-octylfluorenyl-2,7-diyl) (PFO)/TiO2 nanoparticles (NPs) as a donor and Fluorol 7GA as an acceptor has been studied. The energy transfer parameters were calculated by using mathematical models. The dominant mechanism responsible for the energy transfer between the donor and acceptor molecules was Forster-type, as evidenced by large values of quenching rate constant, energy transfer rate constant and critical distance of energy transfer. Moreover, these composites which were used as an emissive layer in organic light emitting diodes, were investigated in terms of current density–voltage and electroluminescence spectra.

Keywords: energy transfer parameters, forster-type, electroluminescence, organic light emitting diodes

Procedia PDF Downloads 426

Authors: O. Hanita, S. A. Ainnul Hamidah, A. H. Yang Zalila, M. R. Siti Nadiah, M. H. Najihah, M. A. Hapipah

Abstract:

The crude extract of the leaves of Actinodaphne sesquipedalis Hook. F. Var. Glabra (Kochummen), was taken under phytochemical investigation. The crude methanolic extract was partitioned with a different solvent system by increasing their polarities (n-hexane, dichloromethane, and methanol). The compounds were fractionated and isolated from n-hexane partition by using column chromatography with silica gel 60 or Sephadex LH-20 as a stationary phase and preparative thin layer chromatographic technique. Isolates were characterized using TLC, FTIR, UV spectrophotometer and NMR spectroscopy. The n-hexane fractionates yielded a total of four compounds namely N-methyllaurotetanine (1), dicentrine (2), β-sitosterol (3), and stigmasterol (4). The result indicates that the leaves of Actinodaphne sesquipedalis may provide a rich source of alkaloids and triterpenoids.

Keywords: actinodaphne sesquipedalis, alkaloids, phytochemical investigation, triterpenoids

Procedia PDF Downloads 397

Authors: Jun Young Moon, Hyeonggeon Lee, Jong Tae Kim

Abstract:

In this paper, we present Cortex-M3 based virtual platform which can virtualize wearable hardware platform and evaluate hardware performance. Cortex-M3 is very popular microcontroller in wearable devices, hardware sensors and display devices. This platform can be used to implement software layer for specific hardware architecture. By using the proposed platform the software development process can be parallelized with hardware development process. We present internal mechanism to implement the proposed virtual platform and describe how to use the proposed platform to develop software by using case study which is low cost wearable device that uses Cortex-M3.

Keywords: electronic system level design, software development, virtual platform, wearable device

Procedia PDF Downloads 375

Authors: H. Yazdani, K. Ghorbanian

Abstract:

This paper deals with modeling and simulation of the plasma actuator with OpenFOAM. Plasma actuator is one of the newest devices in flow control techniques which can delay separation by inducing external momentum to the boundary layer of the flow. The effects of the plasma actuators on the external flow are incorporated into Navier-Stokes computations as a body force vector which is obtained as a product of the net charge density and the electric field. In order to compute this body force vector, the model solves two equations: One for the electric field due to the applied AC voltage at the electrodes and the other for the charge density representing the ionized air. The simulation result is compared to the experimental and typical values which confirms the validity of the modeling.

Keywords: active flow control, flow-field, OpenFOAM, plasma actuator

Procedia PDF Downloads 306

Authors: Arezou Ghadi, Nasrollah Vahedi, Azam Sinkakarimi

Abstract:

For determination of antibiotic residues in slaughtered cow carcasses of Amol city in Iran, sampling has done from 100 heads of cow. For this purpose, the microbiological F.P.T (Four-Plate Test) method was used. Basis of this method, a clear zone is creating around the leachate on the plate that already has cultured a uniform layer of under test bacteria on agar plate. In this study from 100 heads of cow carcasses, at least 75 cases (75%) in one of the tested organs (muscle-liver-kidney) have been antibiotic residues. Also, it has been found that kidney have the most positive cases (60%) than other organs (liver and muscle), then the liver (58%) and finally are muscles (51%).

Keywords: antibiotic residues, agar plate test, cow carcass

Procedia PDF Downloads 455

Authors: Kerekoppa Puttaiah Bhatta Ramesha, Uday Kannegundla, Praseeda Mol, Lathika Gopalakrishnan, Jagish Kour Reen, Gourav Dey, Manish Kumar, Sakthivel Jeyakumar, Arumugam Kumaresan, Kiran Kumar M., Thottethodi Subrahmanya Keshava Prasad

Abstract:

Spermatozoa are the highly specialized transcriptionally and translationally inactive haploid male gamete. The understanding of proteome of sperm is indispensable to explore the mechanism of sperm motility and fertility. Though there is a large number of human sperm proteomic studies, in-depth proteomic information on Bos indicus spermatozoa is not well established yet. Therefore, we illustrated the profile of sperm proteome in indigenous cattle, Malnad gidda (Bos Indicus), using high-resolution mass spectrometry. In the current study, two semen ejaculates from 3 breeding bulls were collected employing the artificial vaginal method. Using 45% percoll purification, spermatozoa cells were isolated. Protein was extracted using lysis buffer containing 2% Sodium Dodecyl Sulphate (SDS) and protein concentration was estimated. Fifty micrograms of protein from each individual were pooled for further downstream processing. Pooled sample was fractionated using SDS-Poly Acrylamide Gel Electrophoresis, which is followed by in-gel digestion. The peptides were subjected to C18 Stage Tip clean-up and analyzed in Orbitrap Fusion Tribrid mass spectrometer interfaced with Proxeon Easy-nano LC II system (Thermo Scientific, Bremen, Germany). We identified a total of 6773 peptides with 28426 peptide spectral matches, which belonged to 1081 proteins. Gene ontology analysis has been carried out to determine the biological processes, molecular functions and cellular components associated with sperm protein. The biological process chiefly represented our data is an oxidation-reduction process (5%), spermatogenesis (2.5%) and spermatid development (1.4%). The highlighted molecular functions are ATP, and GTP binding (14%) and the prominent cellular components most observed in our data were nuclear membrane (1.5%), acrosomal vesicle (1.4%), and motile cilium (1.3%). Seventeen percent of sperm proteins identified in this study were involved in metabolic pathways. To the best of our knowledge, this data represents the first total sperm proteome from indigenous cattle, Malnad Gidda. We believe that our preliminary findings could provide a strong base for the future understanding of bovine sperm proteomics.

Keywords: Bos indicus, Malnad Gidda, mass spectrometry, spermatozoa

Procedia PDF Downloads 196

Authors: Matthew J. Glanville, Christian J. Rohr

Abstract:

Coastal waterspout activity is known to occur globally over a wide climatic range. This study has focussed on recent tornadic waterspout activity along the temperate New South Wales coastline of Australia. Recent tornadic waterspout impacts were surveyed at Kurnell, Kiama, and Lennox Head in coastal New South Wales and are thought to have formed either wholly or partly offshore. It is proposed that a warm, moist layer of air at the sea surface creates more unstable atmospheric conditions than would an approaching supercell path over land, and hence a greater propensity to generate a tornadic event. Measured and observed wind velocities in the vicinity of 60 ms-1 associated with the observed tornadic waterspouts are considerably higher in magnitude than the basic wind speed presented in AS1170.2 for an estimated return period of 2000 years in Region A.

Keywords: coastal, survey, tornadic, waterspout

Procedia PDF Downloads 225

Authors: B. M. Patil

Abstract:

Calcium Zirconate (CaZrO3) has high protonic conductivities at elevated temperature in water or hydrogen atmosphere. Undoped calcium zirconate acts as a p-type semiconductor in air. In this paper, we reported synthesis of CaZrO3 nanoparticles via modified molecular precursor method. The precursor calcium zirconium oxalate (CZO) was synthesized by exchange reaction between freshly generated aqueous solution of sodium zirconyl oxalate and calcium acetate at room temperature. The controlled pyrolysis of CZO in air at 700°C for one hour resulted in the formation nanocrystalline CaZrO3 powder. CaZrO3 obtained by the present method was characterized by Simultaneous thermogravimetry and differential thermogravimetry (TG-DTA), X-ray diffraction (XRD), infra-red spectroscopy and transmission electron microscopy (TEM). The pellets of synthesized CaZrO3 fabricated, sintered at 1000°C for 5 hr and tested as sensors for NO2 and NH3 gases.

Keywords: CaZrO3, CZO, NO2, NH3

Procedia PDF Downloads 167

Authors: Mads H. Clausen

Abstract:

Plant cell walls are structurally complex and contain a larger number of diverse carbohydrate polymers. These plant fibers are a highly valuable bio-resource and the focus of food, energy and health research. We are interested in studying the interplay of plant cell wall carbohydrates with proteins such as enzymes, cell surface lectins and antibodies. However, detailed molecular level investigations of such interactions are hampered by the heterogeneity and diversity of the polymers of interest. To circumvent this, we target well-defined oligosaccharides with representative structures that can be used for characterizing protein-carbohydrate binding. The presentation will highlight chemical syntheses of plant cell wall oligosaccharides from our group and provide examples from studies of their interactions with proteins.

Keywords: oligosaccharides, carbohydrate chemistry, plant cell walls, carbohydrate-acting enzymes

Procedia PDF Downloads 310

Authors: Hyeong-Jin Kim, Jong Kook Lee

Abstract:

Zirconia has biological, mechanical and optical properties, so, it used as a dental implant material in human body. But, it is difficult to form directly bonding with living tissues after the procedure and induces the falling away from implanted parts of the body. To improve this phenomenon, it is essential to increase the surface roughness of zirconia implants and induce a forming-ability of strong bonds. In this study, we performed a room temperature spray coating on zirconia specimen to obtain a highly roughened zirconia surface. To get optimal surface roughness, we controlled the distance between the nozzle and the substrate, coating times and powder condition. Bonding microstructure, surface roughness, and chemical composition of the coating layer were observed by SEM, XRD and roughness tester.

Keywords: implant, aerosoldeposition, zirconia, dental

Procedia PDF Downloads 212

Authors: B. Noruziaan, A. Shvarzman, R. Leahy

Abstract:

An innovative flooring underlayment was produced and tested. The composite system is made of common OSB boards and a layer of eco-friendly non-cement gypsum based material (GeoGypTM). It was found that the shear bond between the two materials is sufficient to secure the composite interaction between the two. The very high compressive strength and relatively high tensile strength of the non-cement based component together with its high modulus of elasticity provides enough strength and stiffness for the composite product to cover wider spacing between the joists. The initial findings of this study indicate that with joist spacing as wide as 800 mm, the flooring system provides enough strength without compromising the serviceability requirements of the building codes.

Keywords: Composite, floor deck, gypsum based, lumber joist, non-cement, oriented strandboard, shear bond

Procedia PDF Downloads 420