Search results for: Trenton Hubbard
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 17

Search results for: Trenton Hubbard

17 Physical Properties of Uranium Dinitride UN2 by Using Density Functional Theory (DFT and DFT+U)

Authors: T. Zergoug, S. E. H. Abaidia, A. Nedjar, M. Y. Mokeddem

Abstract:

Physical properties of uranium di-nitride (UN2) were investigated in detail using first principles calculations based on density functional theory. To treat the strong correlation effects caused by 5f Uranium valence electrons, on-site Coulomb interaction correction via the Hubbard-like term, U (DFT+U) was employed. The UN2 structural, mechanical and thermodynamic properties were calculated within DFT and Various U of DFT+U approach. The Perdew–Burke–Ernzerhof (PBE.5.2) version of the generalized gradient approximation (GGA) is used to describe the exchange-correlation with the projector-augmented wave (PAW) pseudo potentials. A comparative study shows that results are improved by using the Hubbard formalism for a certain U value correction like the structural parameter. For some physical properties the variation versus Hubbard U is strong like Young modulus but for others it is weakly noticeable such as the density of state (DOS) or bulk modulus. We noticed also that up from U=7.5 eV, elastic results become not conform to the cubic cell elastic criteria since the C44 values turn out to be negative.

Keywords: uranium diNitride, UN2, DFT+U, elastic properties

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16 Physical Theory for One-Dimensional Correlated Electron Systems

Authors: Nelson Nenuwe

Abstract:

The behavior of interacting electrons in one dimension was studied by calculating correlation functions and critical exponents at zero and external magnetic fields for arbitrary band filling. The technique employed in this study is based on the conformal field theory (CFT). The charge and spin degrees of freedom are separated, and described by two independent conformal theories. A detailed comparison of the t-J model with the repulsive Hubbard model was then undertaken with emphasis on their Tomonaga-Luttinger (TL) liquid properties. Near half-filling the exponents of the t-J model take the values of the strong-correlation limit of the Hubbard model, and in the low-density limit the exponents are those of a non-interacting system. The critical exponents obtained in this study belong to the repulsive TL liquid (conducting phase) and attractive TL liquid (superconducting phase). The theoretical results from this study find applications in one-dimensional organic conductors (TTF-TCNQ), organic superconductors (Bechgaard salts) and carbon nanotubes (SWCNTs, DWCNTs and MWCNTs). For instance, the critical exponent at from this study is consistent with the experimental result from optical and photoemission evidence of TL liquid in one-dimensional metallic Bechgaard salt- (TMTSF)2PF6.

Keywords: critical exponents, conformal field theory, Hubbard model, t-J model

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15 Signs-Only Compressed Row Storage Format for Exact Diagonalization Study of Quantum Fermionic Models

Authors: Michael Danilov, Sergei Iskakov, Vladimir Mazurenko

Abstract:

The present paper describes a high-performance parallel realization of an exact diagonalization solver for quantum-electron models in a shared memory computing system. The proposed algorithm contains a storage format for efficient computing eigenvalues and eigenvectors of a quantum electron Hamiltonian matrix. The results of the test calculations carried out for 15 sites Hubbard model demonstrate reduction in the required memory and good multiprocessor scalability, while maintaining performance of the same order as compressed row storage.

Keywords: sparse matrix, compressed format, Hubbard model, Anderson model

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14 Efficacy of Single-Dose Azithromycin Therapy for the Treatment of Chlamydia trachomatis in Patients Evaluated for Child Sexual Abuse in an Urban Health Center 2006-16

Authors: Trenton Hubbard, Kenneth Soyemi, Emily Siffermann

Abstract:

Introduction: According to the American Academy of Pediatrics (AAP) there are different weight-based recommendations for the treatment of Chlamydia trachomatis (CT) in patients who are being evaluated for sexual assault. Current AAP Red Book guidelines recommend that uncomplicated C. trachomatis anogenital infection in prepubertal patients weighing less than =<45 kg be treated with oral erythromycin 50 mg/kg/day QID for 14 days with no alternative therapies, and for patients whose weight => 45 kg are Azithromycin 1 gm PO once. Our study objective was to determine the efficacy of single-dose Azithromycin therapy for the treatment of Chlamydia trachomatis in patients weighing less than 50 kg who were evaluated for child sexual abuse in an urban setting. Methods: We conducted a retrospective chart review of historical medical records (paper and electronic) patients weighing less than 50 kg who were evaluated for child sexual abuse and subsequently treated for C. trachomatis infection with Azithromycin (20 mg/kg PO once up to a maximum 1 gm) and received a Test of Cure (TOC) from 2006-2016. Qualitative variables were expressed as percentages. Quantitative variables were expressed as mean values (+/- standard deviation [SD]) if they followed a normal distribution or as median values (interquartile range[IQR]) if they did not. Wilcoxson two-sample test was used to compare means of Azithromycin Dose, mg/kg, and TOC timing between treatment responders and non-responders. Results: We reviewed records of 34 patients, average age (SD) was 5.4 (2.0) years, 33 (97%) were treated for CT and 1(3%) for both GC and CT. 25 (74%) were females. Urine PCR was the most commonly used test at evaluation and as TOC with 13 (38%) patients completing both tests. The average (SD) dose of Azithromycin at treatment was 470 (136) mg and average (SD) mg/kg dose of 20 (1.9) mg/kg for all patients. Median (IQR) timing for TOC testing was 19 (14-26) days. Of the 33 with complete data 25 (74%) had a negative TOC. When compared with treatment non-responders (TOC failures), treatment responders received higher doses (average dose (SD) received 495 (139) vs 401(110), P 0.06)); similar average (SD) weight base dosing received (20.8(2.0) vs 19.7 (1.5), P 0.15)), and earlier average (SD)TOC test timing (18.8 (5.6) vs 32 (28.6) P 0.02)). Conclusion: Azithromycin dosing appears to be efficacious in the treatment of CT post sexual assault as majority of patients responded. Although treatment responders and non-responders received similar weight based doses, there is need for additional studies to understand variances and predictors of response.

Keywords: child sexual abuse, chlmaydia trachmotis infection, single-dose azithromycin, weight less than or equal to 45 kilograms

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13 Quantum Information Scrambling and Quantum Chaos in Silicon-Based Fermi-Hubbard Quantum Dot Arrays

Authors: Nikolaos Petropoulos, Elena Blokhina, Andrii Sokolov, Andrii Semenov, Panagiotis Giounanlis, Xutong Wu, Dmytro Mishagli, Eugene Koskin, Robert Bogdan Staszewski, Dirk Leipold

Abstract:

We investigate entanglement and quantum information scrambling (QIS) by the example of a many-body Extended and spinless effective Fermi-Hubbard Model (EFHM and e-FHM, respectively) that describes a special type of quantum dot array provided by Equal1 labs silicon-based quantum computer. The concept of QIS is used in the framework of quantum information processing by quantum circuits and quantum channels. In general, QIS is manifest as the de-localization of quantum information over the entire quantum system; more compactly, information about the input cannot be obtained by local measurements of the output of the quantum system. In our work, we will first make an introduction to the concept of quantum information scrambling and its connection with the 4-point out-of-time-order (OTO) correlators. In order to have a quantitative measure of QIS we use the tripartite mutual information, in similar lines to previous works, that measures the mutual information between 4 different spacetime partitions of the system and study the Transverse Field Ising (TFI) model; this is used to quantify the dynamical spreading of quantum entanglement and information in the system. Then, we investigate scrambling in the quantum many-body Extended Hubbard Model with external magnetic field Bz and spin-spin coupling J for both uniform and thermal quantum channel inputs and show that it scrambles for specific external tuning parameters (e.g., tunneling amplitudes, on-site potentials, magnetic field). In addition, we compare different Hilbert space sizes (different number of qubits) and show the qualitative and quantitative differences in quantum scrambling as we increase the number of quantum degrees of freedom in the system. Moreover, we find a "scrambling phase transition" for a threshold temperature in the thermal case, that is, the temperature of the model that the channel starts to scramble quantum information. Finally, we make comparisons to the TFI model and highlight the key physical differences between the two systems and mention some future directions of research.

Keywords: condensed matter physics, quantum computing, quantum information theory, quantum physics

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12 DFT Study of Secondary Phase of Cu2ZnSnS4 in Solar Cell: Cu2SnS3

Authors: Mouna Mesbahi, M. Loutfi Benkhedir

Abstract:

In CZTS films solar cell, the preferable reaction between Cu and sulfur vapor was likely to be induced by out diffusion of the bottom Cu component to the surface; this would lead to inhomogeneous distribution of the Cu component to form the Cu2SnS3 secondary phase and formation of many voids and crevices in the resulting CZTS film; which is also the cause of the decline in performance. In this work we study the electronic and optical properties of Cu2SnS3. For this purpose we used the Wien2k code based on the theory of density functional theory (DFT) with the modified Becke-Johnson exchange potential mBJ and the Hubbard potential individually or combined. We have found an energy gap 0.92 eV. The results are in good agreement with experimental results.

Keywords: Cu2SnS3, DFT, electronic and optical properties, mBJ+U, WIEN2K

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11 First Principle Calculations of Magnetic and Electronic Properties of Double Perovskite Ba2MnMoO6

Authors: B. Bouadjemi, S. Bentata, W. Benstaali, A. Souidi, A. Abbad, T. Lantri, Z. Aziz, A. Zitouni

Abstract:

The electronic and magnetic structures of double perovskite Ba2MnMoO6 are systematically investigated using the first principle method of the Full Potential Linear Augmented Plane Waves Plus the Local Orbitals (FP-LAPW+LO) within the Local Spin Density Approximation (LSDA) and the Generalized Gradient Approximation (GGA). In order to take into account the strong on-site Coulomb interaction, we included the Hubbard correlation terms: LSDA+U and GGA+U approaches. Whereas half-metallic ferromagnetic character is observed due to dominant Mn spin-up and Mo spin-down contributions insulating ground state is obtained. The LSDA+U and GGA+U calculations yield better agreement with the theoretical and the experimental results than LSDA and GGA do.

Keywords: electronic structure, double perovskite, first principles, Ba2MnMoO6, half-metallic

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10 An Ab Initio Study of Delafossite Transparent Conductive Oxides Cu(In, Ga)O2 and Absorbers Films Cu(In, Ga)S2 in Solar-Cell

Authors: Mokdad Sakhri, Youcef Bouhadda

Abstract:

Thin film chalcopyrite technology is thus nowadays a solid candidate for photovoltaic cells. The currently used window layer for the solar cell Cu(In,Ga)S2 is our interest point in this work. For this purpose, we have performed a first-principles study of structural, electronic and optical properties for both delafossite transparent conductive oxides Cu (In, Ga)O2 and absorbers films Cu(In,Ga)S2. The calculations have been carried out within the local density functional (LDA) and generalized gradient approximations (GGA) combined with the hubbard potential using norm-conserving pseudopotentials and a plane-wave basis with ABINIT code. We have found the energy gap is :1.6, 2.53, 3.6, 3.8 eV for CuInS2, CuGaS2, CuInO2 and CuGaO2 respectively. The results are in good agreement with experimental results.

Keywords: ABINIT code, DFT, electronic and optical properties, solar-cell absorbers, delafossite transparent conductive oxides

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9 The Implementation of Self-Determination Theory on the Opportunities and Challenges for Blended E-Learning in Motivating Egyptian Logistics Learners

Authors: Aisha Noour, Nick Hubbard

Abstract:

Learner motivation is considered an important premise for the Blended e-Learning (BL) method. BL is an effective learning method in multiple domains, which opens several opportunities for its participants to engage in the learning environment. This research explores the learners’ perspective of BL according to the Self-Determination Theory (SDT). It identifies the opportunities and challenges for using the BL in Logistics Education (LE) in Egyptian Higher Education (HE). SDT is approached from different perspectives within the relationship between Intrinsic Motivation (IM), Extrinsic Motivation (EM) and Amotivation (AM). A self-administered face-to-face questionnaire was used to collect data from learners who were geographically widely spread around three colleges of International Transport and Logistics (CILTs) at the Arab Academy for Science, Technology and Maritime Transport (AAST&MT) in Egypt. Six hundred and sixteen undergraduates responded to a questionnaire survey. Respondents were drawn from three branches in Greater Cairo, Alexandria, and Port Said. The data analysis used was SPSS 22 and AMOS 18.

Keywords: intrinsic motivation, extrinsic motivation, amotivation, blended e-learning, Self Determination Theory

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8 Effect of Microencapsulated Butyric Acid Supplementation on Growth Performance, Ileal Digestibility of Protein, Gut Health and Immunity in Broilers

Authors: Saeed Ahmed, Muhammad Imran, Yasir Allah Ditta, Shahid Mehmood, Zahid Rasool

Abstract:

A study was conducted to investigate the effect of different levels of microencapsulated butyric (MEB) on growth performance, gut health and immunity in commercial broiler chickens. In total, 336 day-old Hubbard classic broilers chicks were randomly assigned to 4 dietary treatments (Control, 0.25, 0.35 and 0.45g/kg of butyric acid) under completely randomized design. Each treatment was replicated 3 times with 28 birds in each replicate. Feed intake, body weight gain, feed conversion ratio, intestinal morphology, apparent ileal digestibility of protein and immunity parameters were evaluated. At the end of the experiment (35-d) 3 birds/replicate in each group were randomly selected and slaughtered to collect blood, duodenal samples and ileal digesta. The data were analyzed by using ANOVA technique. The results indicated improved body weight gain (P = 0.0222), feed conversion ratio (P = 0.0056), duodenal villus height (P = 0.0512), AID (P = 0.0098) antibody titer against Newcastle disease improved (P = 0.0326). Treatments remained unresponsive with respect to feed intake (P = 0.9685).

Keywords: butyric acid, broilers, gut health, ileal digestibility

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7 The Use of Self-Determination Theory to Assess the Opportunities and Challenges for Blended E-Learning in Egypt: An Analysis of the Motivations of Logistics Lecturers

Authors: Aisha Tarek Noour, Nick Hubbard

Abstract:

Blended e-Learning (BL) is proving to be an effective pedagogical tool in many areas of business and management education, but there remains a number of barriers to overcome before its implementation. This paper seeks to analyse the views of lecturers towards BL according to Self-Determination Theory (SDT), and identifies the opportunities and challenges for using BL in Logistics Education in an Egyptian higher education establishment. SDT is approached from a different perspective and the relationship between intrinsic motivation (IM), extrinsic motivation (EM), and amotivation (AM) is analysed and related to the opportunities and challenges of the BL method. The case study methodology comprises of a series of interviews with lecturers employed at three Colleges of International Transport and Logistics (CITLs) at the Arab Academy for Science, Technology, Maritime and Transport (AAST&MT) in Egypt. A structured face-to-face interview was undertaken with 61 interviewees across all faculty positions: Deans, Associate Professors, Assistant Professor, Department Heads, Part-time instructors, Teaching Assistants, and Graduate Teaching Assistants. The findings were based on "content analysis" of the interview transcripts and use of the NVivo10 software program. The research contributes to the application of SDT within the field of BL through an analysis of the views of lecturers towards the opportunities and challenges that BL offers to logistics educators in Egypt.

Keywords: intrinsic motivation, extrinsic motivation, amotivation, autonomy, competence, relatedness, self-determination theory and blended e-learning

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6 Effect of Supplemental Bacterial Phytase at Different Dietary Levels of Phosphorus on Tibial Bone Characteristics and Body Weight Gain in Broilers

Authors: Saqib Saleem Abdullah, Saima Masood, Hafsa Zaneb, Shela Gul Bokhari, Muti Ur Rehman, Jamil Akbar

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A 5- weeks feeding trial was carried out to determine the effectiveness of Bacterial Phytase (Phyzyme®) in broilers, at different dietary levels of Phosphorous. 140 d-old broilers (Hubbard) were randomly divided into 4 groups (n=4). Birds were fed corn-based basal diet or the same diet supplemented with 3 different levels of non Phytate Phosphorous (NPP) (0.45 %, 0.30 % and 0.15 %). Furthermore, the diets were supplemented with bacterial Phytase. Birds were fed ad libitum and kept under thermo neutral conditions. The parameters studied were; body weight gain (BWG), tibial bone characteristics (TBC), serum Calcium (Ca), Phosphorus (P) and Alkaline Phosphatase (AP) levels and tibia ash percentage (TAP). BWG of the broilers was calculated at weekly interval and remaining parameters were calculated after slaughtering the birds at 35thday. Results suggested that Phytase supplementation at 0.30% NPP (Non Phytate Phosphorus + Bacterial Phytase) increased (P < 0.05) the BWG, bone length, bone weight, tibiotarsal index, medullary canal diameter and diaphysis diameter however, rubosticity index was reduced to minimum (P < 0.05) at this dietary level of phosphorous when compared with other groups. Maximum (P < 0.05) rubosticity index was observed in control group with 0% Phytase. Furthermore, Phytase addition at 0.30 % NPP also improved (P < 0.05) Ca, P and AP levels in the blood. Phytase supplementation at lower phosphorus level (0.30%NPP) improved BWG and TBC including bone density and bone quality in broilers hence it can be concluded that addition of Phytase at 0.30% NPP may prove beneficial for bone and overall performance in broilers.

Keywords: diaphysis diameter, phytase, rubosticity index, tibia

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5 Effect of Multi-Enzyme Supplementation on Growth Performance of Broiler

Authors: Abdur Rahman, Saima, T. N. Pasha, Muhammad Younus, Yassar Abbas, Shahid Jaleel

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Non-starch polysaccharides (NSPs) are not completely digested by broiler endogenous enzymes and consequently the soluble NSPs in feed results in high digesta viscosity and poor retention of nutrients. Supplementation of NSPs digesting enzymes may release the nutrients from feed and reduce the anti-nutritional effects of NSP’s. The present study was conducted to determine the effects of NSPs digesting enzymes (Zympex) in broiler chicks. A total of 120 day old broiler chicks (Hubbard) were categorized into 3 treatments and each treatment was having four replicates with 10 birds in each. Dietary treatments comprised of Basal diet (2740 KCal/Kg) as control-1 (T1), low energy diet (2630 KCal/kg) control-2 (T2) and low energy diet with 0.5 gm/Kg enzyme as T3. Multi-enzymes supplementation showed significant (P < 0.05) positive effect on weight gain (last three weeks), feed intake (last two weeks), FCR (1st, 2nd, 4th and 5th) and nutrient retention in T3 when compared with control-2. Weight gain was lower (P < 0.05) in low caloric feed group C when compared with control-1 in all weeks except last week (P > 0.05), feed consumption was significantly lower (P < 0.05) in 5th week and results showed significantly poor FCR (P < 0.05) in 2nd, 3rd and 4th week but non-significant effect in 1st and 5th week when compared with control-1 group, which revealed the positive effect of enzyme supplementation in low energy diet. These results revealed that enzyme supplementation releases more energy from low energy diets and results in equal performance to normal diet.

Keywords: body weight, FCR, feed intake, enzyme, non-starch polysaccharides

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4 Full Fat Soybean Meal as a Substitute for Soybean Meal in Broiler Rations

Authors: R. M. K. S. Chandana, A. P. D. G. Pathirana, N. Priyankarage, W. A. D. Nayananjalie, S. S. P. Silva

Abstract:

Full fat soybean meal (FFSBM) has been used in many parts of the world together with solvent-extracted soybean meal (SBM) in livestock feeds. Although some local FFSBM is available, their use has not been assessed experimentally. This study was carried out to evaluate the use of local extruded FFSBM in broiler rations. Four treatment diets were formulated by incorporating locally produced FFSBM (0, 10, 20, and 30%) as a replacement for soybean meal (SBM) in a two-phase (starter and finisher) feeding program. Two hundred Hubbard F 15 day old broiler chicks were randomly assigned into four treatments with five replicates per each. Bodyweight gain (BWG), feed intakes (FI), and feed conversion ratio (FCR) were calculated for a period of 42 days. Nutrient utilization in the form of dry matter (DM), energy, nitrogen, and fat retention were estimated by the total collection method in three weeks old broilers. At the end of the experiment, carcass weight was measured, and the dressing percentage was calculated. Data were analyzed using one way analysis of variance (ANOVA) in SAS. There was no significant effect of FFSBM on feed intakes of chicks fed different diets (p > 0.05). Birds fed the control diet, and FF10 (10% FFSBM diet) gained significantly more than that of birds fed FF20 or FF30 diets (p > 0.05). In the finisher period, control birds gained more than all the other treatment birds. FCR was poorer in bird fed higher levels of FFSBM compared to the control or FF10 birds during their early life, but that was not evident in the latter part of the experiment. Treatments did not alter (p > 0.05) the retention of DM and nitrogen, but energy utilization was lowest (p < 0.05) in birds fed with 0% FFSBM, and the highest fat digestibility was observed in birds fed with 30% FFSBM diets. Thus, it can be concluded that FFSBM can be used as a substitute for SBM in broiler rations and could be incorporated up to 10% of the diet safely with no adverse effects on broiler performances.

Keywords: body weight, broiler, digestibility, full fat soybean meal, soybean meal

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3 Impact of Two Herbal Seeds Supplementation on Growth Performance and Some Biochemical Blood and Tissue Parameters of Broiler Chickens

Authors: Hamada A. Ahmed, Kadry M. Sadek, Ayman E. Taha

Abstract:

The effects of basil and/or chamomile seed supplementation on the growth of Hubbard broiler chicks were evaluated. The antioxidant effects of these supplements were also assessed. One hundred and twenty 1-day-old broiler chicks were randomly divided into four equal groups. The control group (group 1) was fed a basal diet (BD) without supplementation. Groups 2, 3, and 4 were fed the BD supplemented with 10g basil, 10g chamomile, and 5g basil plus 5g chamomile per kg of food, respectively. Basil supplementation alone or in combination with chamomile non-significantly (P≥0.05) increased final body weight (3.2% and 0.3%, respectively) and weight gain (3.5% and 3.6%, respectively) over the experimental period. Chamomile supplementation alone non-significantly (P≥0.05) reduced final body weight and weight gain over the experimental period by 1.7% and 1.7%, respectively. In comparison to the control group, herbal seed supplementation reduced feed intake and improved the feed conversion and protein efficiency ratios. In general, basil seed supplementation stimulated chicken growth and improved the feed efficiency more effectively than chamomile seed supplementation. The antioxidant activities of basil and/or chamomile supplementation were examined in the thymus, bursa, and spleen. In chickens that received supplements, the level of malondialdehyde was significantly decreased, whereas the activities of glutathione, superoxide dismutase, and catalase were significantly increased (P<0.05). Supplementation of basil and/or chamomile did not affect blood protein levels, but had lipid-lowering effects as evidenced by reduced serum levels of total lipids, triglycerides, and cholesterol. In conclusion, supplementation of basil and/or chamomile improved growth parameters in broiler chicks and had antioxidant and blood lipid-lowering effects. These beneficial effects of basil and/or chamomile supplementation resulted in economically viable production of high-quality white meat containing no harmful residues.

Keywords: herbal additives, basil, chamomile, broiler, growth performance, antioxidant

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2 A Study on ZnO Nanoparticles Properties: An Integration of Rietveld Method and First-Principles Calculation

Authors: Kausar Harun, Ahmad Azmin Mohamad

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Zinc oxide (ZnO) has been extensively used in optoelectronic devices, with recent interest as photoanode material in dye-sensitize solar cell. Numerous methods employed to experimentally synthesized ZnO, while some are theoretically-modeled. Both approaches provide information on ZnO properties, but theoretical calculation proved to be more accurate and timely effective. Thus, integration between these two methods is essential to intimately resemble the properties of synthesized ZnO. In this study, experimentally-grown ZnO nanoparticles were prepared by sol-gel storage method with zinc acetate dihydrate and methanol as precursor and solvent. A 1 M sodium hydroxide (NaOH) solution was used as stabilizer. The optimum time to produce ZnO nanoparticles were recorded as 12 hours. Phase and structural analysis showed that single phase ZnO produced with wurtzite hexagonal structure. Further work on quantitative analysis was done via Rietveld-refinement method to obtain structural and crystallite parameter such as lattice dimensions, space group, and atomic coordination. The lattice dimensions were a=b=3.2498Å and c=5.2068Å which were later used as main input in first-principles calculations. By applying density-functional theory (DFT) embedded in CASTEP computer code, the structure of synthesized ZnO was built and optimized using several exchange-correlation functionals. The generalized-gradient approximation functional with Perdew-Burke-Ernzerhof and Hubbard U corrections (GGA-PBE+U) showed the structure with lowest energy and lattice deviations. In this study, emphasize also given to the modification of valence electron energy level to overcome the underestimation in DFT calculation. Both Zn and O valance energy were fixed at Ud=8.3 eV and Up=7.3 eV, respectively. Hence, the following electronic and optical properties of synthesized ZnO were calculated based on GGA-PBE+U functional within ultrasoft-pseudopotential method. In conclusion, the incorporation of Rietveld analysis into first-principles calculation was valid as the resulting properties were comparable with those reported in literature. The time taken to evaluate certain properties via physical testing was then eliminated as the simulation could be done through computational method.

Keywords: density functional theory, first-principles, Rietveld-refinement, ZnO nanoparticles

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1 Governance of Social Media Using the Principles of Community Radio

Authors: Ken Zakreski

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Regulating Canadian Facebook Groups, of a size and type, when they reach a threshold of audio video content. Consider the evolution of the Streaming Act, Parl GC Bill C-11 (44-1) and the regulations that will certainly follow. The Canadian Heritage Minister's office stipulates, "the Broadcasting Act only applies to audio and audiovisual content, not written journalism.” Governance— After 10 years, a community radio station for Gabriola Island, BC – Canadian Radio-television and Telecommunications Commission (“CRTC”) was approved but never started – became a Facebook Group “Community Bulletin Board - Life on Gabriola“ referred to as CBBlog. After CBBlog started and began to gather real traction, a member of the Group cloned the membership and ran their competing Facebook group under the banner of "free speech”. Here we see an inflection point [change of cultural stewardship] with two different mathematical results [engagement and membership growth]. Canada's telecommunication history of “portability” and “interoperability” made that Facebook Group CBBlog the better option, over broadcast FM radio for a community pandemic information sharing service for Gabriola Island, BC. A culture of ignorance flourishes in social media. Often people do not understand their own experience, or the experience of others because they do not have the concepts needed for understanding. It is thus important they are not denied concepts required for their full understanding. For example, Legislators need to know something about gay culture before they can make any decisions about it. Community Media policies and CRTC regulations are known and regulators can use that history to forge forward with regulations for internet platforms of a size and content type that reach a threshold of audio / video content. Mostly volunteer run media services, provide order of magnitude lower costs over commercial media. (Treating) Facebook Groups as new media.? Cathy Edwards, executive director of the Canadian Association of Community Television Users and Stations (“CACTUS”), calls it new media in that the distribution platform is not the issue. What does make community groups community media? Cathy responded, "... it's bylaws, articles of incorporation that state they are community media, they have accessibility, commitments to skills training, any member of the community can be a member, and there is accountability to a board of directors". Eligibility for funding through CACTUS requires these same commitments. It is risky for a community to invest into a platform as ownership has not been litigated. Is a FaceBook Group an asset of a not for profit society? The memo, from law student, Jared Hubbard summarizes, “Rights and interests in a Facebook group could, in theory, be transferred as property... This theory is currently unconfirmed by Canadian courts. “

Keywords: social media, governance, community media, Canadian radio

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