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2013

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Articles 9301 - 9330 of 11462

Full-Text Articles in Physical Sciences and Mathematics

Bio-Ink Properties And Printability For Extrusion Printing Living Cells, Johnson H. Y Chung, Sina Naficy, Zhilian Yue, Robert Kapsa, Anita Quigley, Simon E. Moulton, Gordon G. Wallace Jan 2013

Bio-Ink Properties And Printability For Extrusion Printing Living Cells, Johnson H. Y Chung, Sina Naficy, Zhilian Yue, Robert Kapsa, Anita Quigley, Simon E. Moulton, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Additive biofabrication (3D bioprinting) makes it possible to create scaffolds with precise geometries, control over pore interconnectivity and architectures that are not possible with conventional techniques. Inclusion of cells within the ink to form a “bio-ink” presents the potential to print 3D structures that can be implanted into damaged/diseased tissue to promote highly controlled cell-based regeneration and repair. The properties of an ‘ink’ are defined by its formulation and critically influence the delivery and integrity of structure formed. Importantly, the ink properties need to conform to biological requirements necessary for the cell system that they are intended to support and …

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Highly Uniform Tio2/Sno2/Carbon Hybrid Nanofibers With Greatly Enhanced Lithium Storage Performance, Zunxian Yang, Qing Meng, Zaiping Guo, Xuebin Yu, Tailiang Guo, Rong Zeng Jan 2013

Highly Uniform Tio2/Sno2/Carbon Hybrid Nanofibers With Greatly Enhanced Lithium Storage Performance, Zunxian Yang, Qing Meng, Zaiping Guo, Xuebin Yu, Tailiang Guo, Rong Zeng

Australian Institute for Innovative Materials - Papers

Highly uniform, relatively large area TiO2/SnO 2/carbon hybrid nanofibers were synthesized by a simple method based on thermal pyrolysis and oxidation of an as-spun titanium-tin/polyacrylonitrile nanoweb composite in an argon atmosphere. This novel composite features the uniform dispersion and encapsulation of highly uniform nanoscale TiO 2/SnO2 crystals in a porous carbon matrix. The high porosity of the nanofiber composite material, together with the conductive carbon matrix, enhanced the electrochemical performance of the TiO 2/SnO2/carbon nanofiber electrode. The TiO 2/SnO2/carbon nanofiber electrode displays a reversible capacity of 442.8 mA h g-1 for up to 100 cycles, and exhibits excellent rate capability. …

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Limiting Thermomagnetic Avalanches In Superconducting Films By Stop-Holes, F Colauto, J I. Vestgarden, A M H De Andrade, A A M Oliveira, Wilson Aires Ortiz, Tom H. Johansen Jan 2013

Limiting Thermomagnetic Avalanches In Superconducting Films By Stop-Holes, F Colauto, J I. Vestgarden, A M H De Andrade, A A M Oliveira, Wilson Aires Ortiz, Tom H. Johansen

Australian Institute for Innovative Materials - Papers

It is demonstrated that circular holes in superconducting films of Nb can arrest the propagation of thermomagnetic avalanches. The effect was found over a range of temperatures where the material is susceptible to this instability. For other hole shapes, like square and triangular, the sharp corners provoke secondary avalanches, thus extending the breakdown. Making use of circular stop-holes can become a practical way to limit thermomagnetic breakdown in superconducting films.

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One-Pot Green Synthesis Of Ag Nanoparticles-Decorated Reduced Graphene Oxide For Efficient Nonenzymatic H2o2 Biosensor, Mingyan Wang, Tao Shen, Meng Wang, Dongen Zhang, Jun Chen Jan 2013

One-Pot Green Synthesis Of Ag Nanoparticles-Decorated Reduced Graphene Oxide For Efficient Nonenzymatic H2o2 Biosensor, Mingyan Wang, Tao Shen, Meng Wang, Dongen Zhang, Jun Chen

Australian Institute for Innovative Materials - Papers

Ag nanoparticles (AgNP) with an average size of 12 nm are successfully decorated on the reduced graphene oxide (rGO) sheets through a simple one-pot hydrothermal method using gallic acid as the reducing agent. This AgNP/rGO hybrid has been successfully applied in the catalytic performance toward the reduction of H2O2. The nonenzymatic sensor demonstrates a linear relationship in a wide concentration range of 0.05-5 mM (R=0.999), and a high sensitivity of 255 μA cm-2 mM-1 to the detection of H2O2.

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Enhancing Superconducting Properties Of Mgb2 Pellets By Addition Of Amorphous Magnetic Ni-Co-B Nanoparticles, Mislav Mustapic, Josip Horvat, Md Shahriar Hossain, Zeljko Skoko, S X. Dou Jan 2013

Enhancing Superconducting Properties Of Mgb2 Pellets By Addition Of Amorphous Magnetic Ni-Co-B Nanoparticles, Mislav Mustapic, Josip Horvat, Md Shahriar Hossain, Zeljko Skoko, S X. Dou

Australian Institute for Innovative Materials - Papers

Amorphous magnetic Ni-Co-B nanoparticles with an average size of 5 nm were added to precursor powders of MgB2 superconductor. The preparation procedure for MgB2 pellets was optimized for obtaining the best critical current density (Jc) at elevated magnetic fields. Addition of Ni-Co-B decreases the Jc for heat treatment of precursor powders at 650 ° C. Heat treatments at 770 ° C and higher improve Jc at 20 and 5 K. This improvement occurs at both temperatures through the increase of the effective connectivity between MgB2 crystals. Vortex pinning was enhanced at 5 K, but not at 20 K. Ni-Co-B nanoparticles …

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Time-Of-Flight Polarized Neutron Reflectometry On Platypus: Status And Future Developments, T Saerbeck, D L. Cortie, S Bruck, J Bertinshaw, S A. Holt, A Nelson, M James, W T. Lee, F Klose Jan 2013

Time-Of-Flight Polarized Neutron Reflectometry On Platypus: Status And Future Developments, T Saerbeck, D L. Cortie, S Bruck, J Bertinshaw, S A. Holt, A Nelson, M James, W T. Lee, F Klose

Australian Institute for Innovative Materials - Papers

Time-of-flight (ToF) polarized neutron reflectometry enables the detailed investigation of depth-resolved magnetic structures in thin film and multilayer magnetic systems. The general advantage of the time-of-flight mode of operation over monochromatic instruments is a decoupling of spectral shape and polarization of the neutron beam with variable resolution. Thus, a wide Q-range can be investigated using a single angle of incidence, with resolution and flux well-adjusted to the experimental requirement. Our paper reviews the current status of the polarization equipment of the ToF reflectometer PLATYPUS and presents first results obtained on stratified Ni80Fe20/α-Fe2O3 films, revealing the distribution of magnetic moments in …

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Review On Shear Thickening Fluids And Applications, Jie Ding, Phillip J. Tracey, Weihua Li, Gangrou Peng, Philip G. Whitten, Gordon G. Wallace Jan 2013

Review On Shear Thickening Fluids And Applications, Jie Ding, Phillip J. Tracey, Weihua Li, Gangrou Peng, Philip G. Whitten, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Recently, research in the area of shear thickening fluids (STFs) has increased due to the potential for commercial application. They are considered possible candidate materials for liquid body armour and sporting protective clothing and other applications because of their unique properties. Here the state of the art of shear thickening mechanisms, ingredient materials, fabrication methods, rheological properties, and factors influencing shear thickening behaviour have been reviewed. Basic models used to describe shear thickening behavior are also discussed. Relevant patent applications, particularly in the area of body armour, as well as other industrial applications, such as smart structures, and devices with …

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Modulation Of The Properties Of Thin Ferromagnetic Films With An Externally Applied Electric Field In Ferromagnetic/Piezoelectric/Ferromagnetic Hybrids, D Stamopoulos, M Zeibekis, Shujun Zhang Jan 2013

Modulation Of The Properties Of Thin Ferromagnetic Films With An Externally Applied Electric Field In Ferromagnetic/Piezoelectric/Ferromagnetic Hybrids, D Stamopoulos, M Zeibekis, Shujun Zhang

Australian Institute for Innovative Materials - Papers

In many cases, technological advances are based on artificial low-dimensional structures of heterogeneous constituents, thus called hybrids, that when come together they provide stand-alone entities that exhibit entirely different properties. Such hybrids are nowadays intensively studied since they are attractive for both basic research and oncoming practical applications. Here, we studied hybrids constituted of piezoelectric (PE) and ferromagnetic (FM) components in the form FM/PE/FM, ultimately aiming to provide means for the controlled modulation of the properties of the FM electrodes, originating from the strain imposed to them by the PE mediator when an electric field is applied. The PE component …

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Crystal Growth, Structure And Thermal Properties Of Noncentrosymmetric Single Crystals Prca4o(Bo3)3+, Fapeng Yu, Shujun Zhang, Xiufeng Cheng, Xiulan Duan, Tingfeng Ma, Xian Zhao Jan 2013

Crystal Growth, Structure And Thermal Properties Of Noncentrosymmetric Single Crystals Prca4o(Bo3)3+, Fapeng Yu, Shujun Zhang, Xiufeng Cheng, Xiulan Duan, Tingfeng Ma, Xian Zhao

Australian Institute for Innovative Materials - Papers

Noncentrosymmetric praseodymium calcium oxyborate single crystals, PrCa4O(BO3)3 (PrCOB), were grown by the Czochralski technique. The monoclinic unit cell parameters were found to be a = 8.177 Å, b = 16.157 Å, c = 3.629 Å and Z = 2 with space group Cm. Crystal density was measured using the Archimedes method, being on the order of 3.47 g cm-3. Thermal properties of PrCOB were investigated, where the specific heat was found to be 0.63 J g-1 °C-1 at room temperature, increasing to 0.85 J g-1°C-1 at 700°C. The thermal expansion coefficients were measured to be α11 = 7.99, α22 = …

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Applications Of Voltammetric Ion Selective Electrodes To Complex Matrices, Alexander R. Harris, Jie Zhang, Robert W. Cattrall, Alan M. Bond Jan 2013

Applications Of Voltammetric Ion Selective Electrodes To Complex Matrices, Alexander R. Harris, Jie Zhang, Robert W. Cattrall, Alan M. Bond

Australian Institute for Innovative Materials - Papers

The practical application of two different voltammetric ion selective electrodes (VISE) to measure ion activity in complex solutions has been explored. 7,7,8,8-tetracyanoquinodimethane (TCNQ) and tetrathiafulvalene (TTF) microcrystals adhered to an electrode surface act as a low selectivity voltammetric ion sensor. Resistance drop effects and pH artifacts were minimised by the addition of an "innocent" supporting electrolyte (buffer) to the analyte solution. In this format, addition of an ionophore to improve selectivity resulted in a reduction in current magnitude, due to competition for the ion. In contrast, voltammetry of a thin film containing a redox active species, electrolyte, ionophore and membrane …

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Levetiracetam-Loaded Biodegradable Polymer Implants In The Tetanus Toxin Model Of Temporal Lobe Epilepsy In Rats, Amy J. Halliday, Toni E. Campbell, Timothy S. Nelson, Karen J. Mclean, Gordon G. Wallace, Mark J. Cook Jan 2013

Levetiracetam-Loaded Biodegradable Polymer Implants In The Tetanus Toxin Model Of Temporal Lobe Epilepsy In Rats, Amy J. Halliday, Toni E. Campbell, Timothy S. Nelson, Karen J. Mclean, Gordon G. Wallace, Mark J. Cook

Australian Institute for Innovative Materials - Papers

Approximately one-third of people with epilepsy receive insufficient benefit from currently available anticonvulsant medication, and some evidence suggests that this may be due to a lack of effective penetration into brain parenchyma. The current study investigated the ability of biodegradable polymer implants loaded with levetiracetam to ameliorate seizures following implantation above the motor cortex in the tetanus toxin model of temporal lobe epilepsy in rats. The implants led to significantly shorter seizures and a trend towards fewer seizures for up to 1 week. The results of this study indicate that drug-eluting polymer implants represent a promising evolving treatment option for …

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Structurally Homogeneous Mgb2 Superconducting Wires Through Economical Wet Mixing Process, Md Shahriar A. Hossain, Ashkan Motaman, Xun Xu, Khay Way See, Ozlem Cicek, Hasan Agil, Ercan Ertekin, Ali Gencer, Kookchae Cheong, Minoru Maeda, S X. Dou Jan 2013

Structurally Homogeneous Mgb2 Superconducting Wires Through Economical Wet Mixing Process, Md Shahriar A. Hossain, Ashkan Motaman, Xun Xu, Khay Way See, Ozlem Cicek, Hasan Agil, Ercan Ertekin, Ali Gencer, Kookchae Cheong, Minoru Maeda, S X. Dou

Australian Institute for Innovative Materials - Papers

We evaluate the effects of the mixing process between the starting materials on the structural and superconducting properties of carbon-doped MgB2 wires. The critical current density, n-value, amount of MgO, and critical temperature are obviously dependent on the mixing process, while the microstructure, i.e., grain size, is not sensitive. In our study, the wet-mixing process in toluene enables more homogenous mixing between the starting materials, resulting in superior J(c) and n-value.

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Raman Scattering Studies Of Strain Effects In (100) And (311)B Gaas 1-Xbix Epitaxial Layers, J A. Steele, Roger A. Lewis, M Henini, O M. Lemine, A Alkaoud Jan 2013

Raman Scattering Studies Of Strain Effects In (100) And (311)B Gaas 1-Xbix Epitaxial Layers, J A. Steele, Roger A. Lewis, M Henini, O M. Lemine, A Alkaoud

Australian Institute for Innovative Materials - Papers

We report room-temperature Raman studies of strained (100) and (311)B GaAs1-xBix epitaxial layers for x ≤ 0.039. The Raman spectra exhibit a two-mode behavior, as well as disorder-activated GaAs-like phonons. The experimental results show that the GaAs-like LO(Γ) mode experiences a strong composition-dependent redshift as a result of alloying. The peak frequency decreases linearly from the value for pure GaAs (∼293 cm-1) with the alloyed Bi fraction x and the introduced in-plane lattice strain ε, by Δ ω LO = Δ ω alloy-Δ ω strain. X-ray diffraction measurements are used to determine x and ε allowing Δ ω alloy to …

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Studying Inhomogeneity Of Organic Coatings Using Wire Beam Multielectrode And Physicomechanical Testing, Sina S. Jamali, D J. Mills Jan 2013

Studying Inhomogeneity Of Organic Coatings Using Wire Beam Multielectrode And Physicomechanical Testing, Sina S. Jamali, D J. Mills

Australian Institute for Innovative Materials - Papers

The effect of thickness, curing temperature and solvent on the structural inhomogeneity of several types of organic coatings has been investigated. The local distribution of electrochemical resistance was studied using a wire beam multielectrode array, while the inhomogeneity at a larger scale was examined using ∼3 cm2 area detached coatings. Physicomechanical tests were also employed to address the structural changes occurring because of variation in curing temperature and the type (or absence) of solvent. Results acquired by wire beam electrode and from the detached coatings showed that increasing the thickness and curing temperature improves the homogeneity of the coating as …

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Signature Of Aromatic Carbons In The Terahertz Spectroscopy Of Bio-Chars, L M. Lepodise, J Horvat, Roger A. Lewis Jan 2013

Signature Of Aromatic Carbons In The Terahertz Spectroscopy Of Bio-Chars, L M. Lepodise, J Horvat, Roger A. Lewis

Australian Institute for Innovative Materials - Papers

The potential of terahertz spectroscopy in distinguishing aromatic carbon compounds in bio-chars is The potential of terahertz spectroscopy in distinguishing aromatic carbon compounds in bio-chars is demonstrated. Several types of biochar samples were measured and compared with the THz spectra of pure aromatic compounds. Infrared spectra were modeled with B3LYP and mP2PLYP methods. Modeling could not identify accurately each of the absorption lines. However modeling shows that one of the lines close to 500 cm-1 is due to vibrations of carbon rings, which can be used for identification of aromatic carbons in biochars. and compared with the THz spectra of …

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Electrochemically Synthesized Stretchable Polypyrrole/Fabric Electrodes For Supercapacitor, Binbin Yue, Caiyun Wang, Xin Ding, Gordon G. Wallace Jan 2013

Electrochemically Synthesized Stretchable Polypyrrole/Fabric Electrodes For Supercapacitor, Binbin Yue, Caiyun Wang, Xin Ding, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Wearable electronics offer the combined advantages of both electronics and fabrics. Being an indispensable part of these electronics, lightweight, stretchable and wearable power sources are strongly demanded. Here we describe a daily-used cotton fabric coated with polypyrrole as electrode for stretchable supercapacitors. Polypyrrole was synthesized on the Au coated fabric via an electrochemical polymerization process with p-toluenesulfonic acid (p-TS) as dopant from acetonitrile solution. This material was characterized with FESEM, tensile stress, and studied as a supercapacitor electrode in 1.0 M NaCl. This conductive textile electrode can sustain up to 140% strain without electric failure. It delivers a high specific …

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Eigenvalue Pairing In The Response Matrix For A Class Of Network Models With Circular Symmetry, Miriam Farber, Charles R. Johnson, Wei Zhen Jan 2013

Eigenvalue Pairing In The Response Matrix For A Class Of Network Models With Circular Symmetry, Miriam Farber, Charles R. Johnson, Wei Zhen

Arts & Sciences Articles

We consider the response matrices in certain weighted networks that display a circular symmetry. It had been observed empirically that these exhibit several paired (multiplicity two) eigenvalues. Here, this pairing is explained analytically for a version of the model more general than the original. The exact number of necessarily paired eigenvalues is given in terms of the structure of the model, and the special structure of the eigenvectors is also described. Examples are provided.

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Commutants And Hyper-Reflexivity Of Multiplication Operators, Masoumeh Faghih Ahmadi, Karim Hedayatian Jan 2013

Commutants And Hyper-Reflexivity Of Multiplication Operators, Masoumeh Faghih Ahmadi, Karim Hedayatian

Turkish Journal of Mathematics

We characterize the commutants of some multiplication operators on a Banach space of analytic functions defined on a bounded domain in the plane. Under certain conditions on the symbol of a multiplication operator, we show that its commutant is a set of multiplication operators. This partially answers a question of Axler, Cuckovic and Rao. Next, the hyper-reflexivity of these multiplication operators are proved. The paper is concluded by proving the hyper-reflexivity of the multiplication operators with symbols \varphi (z) = z^k, k=1, 2,... .

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Cartan Equivalence Problem For Third-Order Differential Operators, Mehdi Nadjafikhah, Rohollah Bakhshandeh Chamazkoti Jan 2013

Cartan Equivalence Problem For Third-Order Differential Operators, Mehdi Nadjafikhah, Rohollah Bakhshandeh Chamazkoti

Turkish Journal of Mathematics

This article is dedicated to solving the equivalence problem for a pair of third-order differential operators on the line under general fiber-preserving transformation using the Cartan method of equivalence. We will treat 2 versions of equivalence problems: first, the direct equivalence problem, and second, an equivalence problem to determine conditions on 2 differential operators such that there exists a fiber-preserving transformation mapping one to the other according to gauge equivalence.

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Colombeau Solutions Of A Nonlinear Stochastic Predator--Prey Equation, Uluğ Çapar Jan 2013

Colombeau Solutions Of A Nonlinear Stochastic Predator--Prey Equation, Uluğ Çapar

Turkish Journal of Mathematics

The solution of a random semilinear hyperbolic system with singular initial data is sought as a random Colombeau distribution. The product of 2 additive white noises is well tackled within the theory of random Colombeau distributions. In the special case of a random predator--prey system, the exact Colombeau solution is obtained under some assumptions when the process is driven by doubly reflected Brownian motions.

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Simple, Complete, And Novel Quantitative Model Of Holography For Students Of Science And Science Education, Dale Olson Jan 2013

Simple, Complete, And Novel Quantitative Model Of Holography For Students Of Science And Science Education, Dale Olson

Faculty Publications

A Moiré graphical method for predicting the directions of all permitted image waves for thin and volume holograms is described. This method has been developed in connection with a holography centred optics course for students in science, technology and science education that has evolved over several decades. A somewhat unique view of the holographic process underlies this novel method of predicting the behaviour of diffraction gratings.

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Applications Of Leggett Williams Type Fixed Point Theorems To A Second Order Difference Equation, Charley Lockhart Seelbach Jan 2013

Applications Of Leggett Williams Type Fixed Point Theorems To A Second Order Difference Equation, Charley Lockhart Seelbach

Online Theses and Dissertations

Using extensions of the Leggett-Williams fixed-point theorem, we prove the existence of solutions for a class of second-order difference equations with Dirichlet boundary conditions. We present these fixed point theorems and then show what conditions have to be met in order to satisfy the theorem. Finally, we provide specific examples to show the hypotheses of the theorems do not contradict one another.

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Increasing Automaticity, Sara Burns Jan 2013

Increasing Automaticity, Sara Burns

Online Theses and Dissertations

Automaticity is defined as the process of developing fluency in mathematics and the ability to answer a basic math problem routinely. Automaticity is one of the most important skills that a student can possess in mathematics. While there are many ways that an educator can implement strategies to increase automaticity in the classroom, the purpose of this study was to determine which of these methods of implementation is more effective: requiring students to practice automaticity three times per week or requiring students to practice automaticity five times per week.

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Gaussian Amicable Pairs, Ranthony Ashley Clark Jan 2013

Gaussian Amicable Pairs, Ranthony Ashley Clark

Online Theses and Dissertations

Amicable pairs are two integers where the sum of the proper divisors of one is the other and vice versa. Since the Gaussian integers have many of the properties of the regular integers, we sought to discover whether there exist any pairs of Gaussian integers with the same property. It turns out that they do exist. In fact, some of the normal amicable pairs carry over as Gaussian amicable pairs. Also discovered are pairs that have a complex part.

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Positive Solutions, Existence Of Smallest Eigenvalues, And Comparison Of Smallest Eigenvalues Of A Fourth Order Three Point Boundary Value Problem, Sarah Schulz King` Jan 2013

Positive Solutions, Existence Of Smallest Eigenvalues, And Comparison Of Smallest Eigenvalues Of A Fourth Order Three Point Boundary Value Problem, Sarah Schulz King`

Online Theses and Dissertations

The existence of smallest positive eigenvalues is established for the linear differential equations $u^{(4)}+\lambda_{1} q(t)u=0$ and $u^{(4)}+\lambda_{2} r(t)u=0$, $0\leq t \leq 1$, with each satisfying the boundary conditions $u(0)=u'(p)=u''(1)=u'''(1)=0$ where $1-\frac{\sqrt{3}}{3}\le p < 1$. A comparison theorem for smallest positive eigenvalues is then obtained. Using the same theorems, we will extend the problem to the fifth order via the Green's Function and again via Substitution. Applying the comparison theorems and the properties of $u_0$-positive operators to determine the existence of smallest eigenvalues. The existence of these smallest eigenvalues is then applied to characterize extremal points of the differential equation $u^{(4)} + q(t)u = 0$ satisfying boundary conditions $u(0) = u'(p) = u''(b) = u'''(b)= 0$ where $1-\frac{

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Remarks On The Paper ``On Some New Inequalities For Convex Functions\\" By M. Tunç, Alfred Witkowski Jan 2013

Remarks On The Paper ``On Some New Inequalities For Convex Functions\\" By M. Tunç, Alfred Witkowski

Turkish Journal of Mathematics

In this note, we slightly generalize Theorem 2 in the paper by M. Tunç and point out that the assumption of Theorem 3 is not sufficient. A misuse of the term 'mean' is also discussed.

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Anchored Sheet Pile Wall Design In Expansive Soils, Ömer Bilgin, Eman Mansour Jan 2013

Anchored Sheet Pile Wall Design In Expansive Soils, Ömer Bilgin, Eman Mansour

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

Expansive soils cause damage to civil engineering structures in various parts of the world, because they swell when absorb water and shrink when dry out. Due to swelling pressures, retaining walls can be subjected to additional lateral pressures causing increased wall deformations and bending moments. Anchor forces can also increase, if the walls are anchored. When expansive soils are present behind retaining walls, swell pressures should also be considered during design in addition to the traditional lateral earth pressures. This study proposes a method to predict potential swell pressures acting on retaining walls for use in design of these walls. …

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Assessing Total Nitrogen In Surface-Water Samples: Precision And Bias Of Analytical And Computational Methods, David L. Rus, Charles J. Patton, David K. Mueller, Charles G. Crawford Jan 2013

Assessing Total Nitrogen In Surface-Water Samples: Precision And Bias Of Analytical And Computational Methods, David L. Rus, Charles J. Patton, David K. Mueller, Charles G. Crawford

United States Geological Survey: Water Reports and Publications

The characterization of total-nitrogen (TN) concentrations is an important component of many surface-water-quality programs. However, three widely used methods for the determination of total nitrogen—(1) derived from the alkaline-persulfate digestion of whole-water samples (TN-A); (2) calculated as the sum of total Kjeldahl nitrogen and dissolved nitrate plus nitrite (TN-K); and (3) calculated as the sum of dissolved nitrogen and particulate nitrogen (TN-C)—all include inherent limitations. A digestion process is intended to convert multiple species of nitrogen that are present in the sample into one measureable species, but this process may introduce bias. TN-A results can be negatively biased in the …

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Hydrographic Surveys Of The Missouri And Yellowstone Rivers At Selected Bridges And Through Bismarck, North Dakota, During The 2011 Flood, Brenda K. Densmore, Kellan R. Strauch, Benjamin J. Dietsch Jan 2013

Hydrographic Surveys Of The Missouri And Yellowstone Rivers At Selected Bridges And Through Bismarck, North Dakota, During The 2011 Flood, Brenda K. Densmore, Kellan R. Strauch, Benjamin J. Dietsch

United States Geological Survey: Water Reports and Publications

The United States Geological Survey (USGS), in cooperation with the North Dakota Department of Transportation and the North Dakota State Water Commission, completed hydrographic surveys at six Missouri River bridges and one Yellowstone River bridge during the 2011 flood of the Missouri River system. Bridges surveyed are located near the cities of Cartwright, Buford, Williston, Washburn, and Bismarck, N. Dak. The river in the vicinity of the bridges and the channel through the city of Bismarck, N. Dak., were surveyed. The hydrographic surveys were conducted using a high-resolution multibeam echosounder (MBES), the RESON SeaBatTM 7125, during June 6–9 and June …

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Calcium Concentration Fluctuations And Subspace Volume Influence Calcium-Regulated Calcium Channel Gating And Subspace Dynamics, Seth H. Weinberg, Gregory D. Smith Jan 2013

Calcium Concentration Fluctuations And Subspace Volume Influence Calcium-Regulated Calcium Channel Gating And Subspace Dynamics, Seth H. Weinberg, Gregory D. Smith

Arts & Sciences Articles

No abstract provided.

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