bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental and Theoretical Investigation of the Plastic Deformation of Cantilever Beams Subjected to Impulsive Loading
Authors: Bodner S. R. , Symonds P. S.
Published: October 2011

The experimental techniques and the results obtained in a program to evaluate the assumptions of dynamic, rigid-plastic theory of beams are presented. The experiments used steel and aluminum-alloy cantilever beams subjected to either a rapid velocity change at the base or to an impulsive load at the tip. A rigid-plastic theory that includes the strain-rate dependence of the yield stress and geometry changes is outlined for the case of the tip impulsive loading. The predictions of this theory are in satisfactory agreement with the experimental results.
Dispersion of Axially Symmetric Waves in Elastic Rods
Authors: Onoe Morio , McNiven H. D. , Mindlin R. D.
Published: October 2011

The relation between frequency and propagation constant, for axially symmetric waves in an infinitely long, isotropic, circular rod, as given by Pochhammer’s equation, is explored. A spectrum, covering a large range of frequencies, is developed for real, imaginary, and complex propagation constants, and the influence of Poisson’s ratio is described.
Adiabatic Analysis of Elastic, Centrally Pivoted, Sector, Thrust-Bearing Pads
Authors: Sternlicht B. , Carter G. K. , Arwas E. B.
Published: October 2011

This paper emphasizes the importance of temperature in thrust-bearing analysis. The analysis presented consists of simultaneous solution of the momentum, energy, and elasticity equations for centrally pivoted, sector-shaped, thrust-bearing pads. Elastic deformations due to the pressure distribution and thermal gradients are considered. Laminar and adiabatic conditions are assumed in the fluid film, and the lubricant is incompressible.
Thermodynamic Analysis of the Darcy Law
Authors: Mokadam R. G.
Published: October 2011

The Darcy law is used extensively to describe the flow of fluids through porous media. According to this law the fluid flow is linearly dependent upon the pressure gradient and the gravitational force. The proportionality factor is generally known as the permeability of the porous medium. The Darcy law cannot be derived from the Navier-Stokes equation since this equation includes terms which characterize the fluid only. With the help of nonreversible thermodynamics it is possible to develop a general equation of motion of a fluid through a porous body, and obtain the Darcy law as a special case of such an equation.
Propagations of Elastic Waves Generated by Dynamical Loads on a Circular Cavity
Authors: Eringen A. C.
Published: October 2011

The Fourier-transform technique has been employed to solve the exterior elasto-dynamic problem concerning the region outside a circular cavity in a plane elastic body. The normal and tangential tractions acting at the surface of the circular cavity are prescribed as arbitrary functions of the polar angle θ, and the time t. The case of impact, blast, and moving loads are studied in detail.
Stress Distribution on the Boundary of a Circular Hole in a Large Plate During Passage of a Stress Pulse of Long Duration
Authors: Durelli A. J. , Riley W. F.
Published: October 2011

A partial solution to the problem of the stress distribution on the boundary of a circular hole in a large plate during passage of a stress pulse of relatively long duration is presented. The solution was obtained experimentally by using a low-modulus model material in a combined photoelasticity and grid analysis. The long-duration stress pulse was applied by loading a small region on an edge of the plate with a falling weight. The hole was placed at a location in the plate where both dilatational and distortional waves would be felt. It was also located in such a way that a symmetric point was available for making free-field stress determinations. The results of the investigation indicate that a variable biaxial state of stress was produced in the free field. The study also indicates that the maximum compressive stress on the hole boundary can be computed with a fair degree of accuracy by applying the Kirsch solution for a hole in an infinite plate and considering the free-field biaxial stress conditions. The maximum tensile stresses on the hole boundary were always found to be smaller than the values predicted by the Kirsch formula.
Investigation of Flat-Plate Hypersonic, Turbulent Boundary Layers With Heat Transfer
Authors: Winkler Eva M.
Published: October 2011

Naturally turbulent boundary layers on a cooled flat plate have been investigated at several distances from the leading edge of the plate at a Mach number of 5.2 for three rates of steady-state heat transfer to the surface. Measurements of Pitot and static pressures and of total and wall temperatures made it possible to compute velocity profiles, static-temperature profiles, and boundary-layer parameters without resorting to assumptions. The data demonstrate that the Reynolds analogy between skin friction and heat transfer is valid for all conditions of the present experiments. With increasing rate of heat transfer to the surface, the skin-friction coefficient was found to decrease, a phenomenon opposite to that predicted by theories and empirical relations. On the basis of the present data and other published results of compressible and incompressible turbulent boundary-layer skin friction, a simple relation was devised which describes closely the variation of the skin-friction coefficient with Mach number, heat-transfer rate, and momentum-thickness Reynolds number.
On the Parametric Excitation of Pendulum-Type Vibration Absorber
Authors: Sevin Eugene
Published: October 2011

The free motion of an undamped pendulum-type vibration absorber is studied on the basis of approximate nonlinear equations of motion. It is shown that this type of mechanical system exhibits the phenomenon of auto parametric excitation; a type of “instability” which cannot be accounted for on the basis of the linearized system. Complete energy transfer between modes is shown to occur when the beam frequency is twice the simple pendulum frequency. On the basis of a numerical solution, approximately 150 cycles of the beam oscillation take place during a single cycle of energy interchange.
Torsion of Sandwich Plates of Trapezoidal Cross Section
Authors: Cheng Shun
Published: October 2011

A system of suitable stress-strain relations as well as equations of equilibrium are derived and solved for the torsion of sandwich plates of trapezoidal cross section. The facings are treated as isotropic solid membranes of equal thickness while the core is of such a nature that its stiffnesses associated with plane-stress components are negligibly small.
An Addition to the Theory of Whirling
Authors: Kane T. R.
Published: October 2011

Particular solutions of the equations of motion of a heavy disk attached at the center of a light, vertical, elastic shaft are used to describe a variety of forms of whirling. The stability of these motions is analyzed by a perturbation method.
An Approximate Analytical Solution for the Stepped Bearing
Authors: Kettleborough C. F.
Published: October 2011

Previously, solutions of the problem of the Rayleigh-type bearing with a step which is not straight have involved the use of the electrolytic tank or the use of relaxation methods, both of which are somewhat inconvenient as compared with the approximate analytical method described in this paper. The solution of the derived differential equation is in the form of a convergent infinite series, but for rapid computation it is shown that an economized series (the τ method for the solution of linear differential equations) yields results of high accuracy.
Theory of Stress Concentration for Shear-Strained Prismatical Bodies With Arbitrary Nonlinear Stress-Strain Law
Authors: Neuber H.
Published: October 2011

Knowledge of stress concentration is very important for engineers in many practical cases. But the stress-concentration factors for Hooke’s law often cannot be used because most technical materials have stress-strain laws deviating from Hooke’s law. In the second edition of his book “Kerbspannungslehre” the author gave a calculation method for a special nonlinear deformation law. In the present paper a general theory for arbitrary stress-strain laws is established which leads to a calculation method for the real values of the concentrated stresses in the material.
A Numerical Solution of the Nonlinear Equations for Axisymmetric Bending of Shallow Spherical Shells
Authors: Thurston G. A.
Published: October 2011

A numerical solution is obtained for the nonlinear equations for clamped, shallow spherical shells under external pressure. Results are presented in the postbuckling range which have not been computed previously. The upper and lower buckling pressures are compared with the experimental data of Kaplan and Fung.
The Effect of Rotatory Inertia and of Shear Deformation on the Frequency and Normal Mode Equations of Uniform Beams With Simple End Conditions
Authors: Huang T. C.
Published: October 2011

New frequency and normal mode equations for flexural vibrations of six common types of simple, finite beams are presented. The derivation includes the effect of rotatory inertia and transverse-shear deformation. A specific example is given.
The Effects of Boundary Design on the Efficiency of Large-Scale Hot Water Heat Stores
Authors: Panthalookaran Varghese , Heidemann Wolfgang , Müller-Steinhagen Hans
Published: October 2011

Boundary design of stratified hot water heat stores is important not only to minimize the thermal losses to the ambient but also to preserve the thermodynamic quality of the stored energy. A new method of characterization, which equivalently accounts for both these concerns, is applied in this paper to investigate into the boundary design of large-scale hot water heat stores. A variety of concepts related to general design of the containments, namely, the effects of the thermal conductivity and thickness of the container wall, are numerically analyzed. The design insights provided by the analysis are in good agreement with the corresponding experimental results for small-scale hot water heat stores found in the literature. Different ways of insulation application, differential application of the external insulation, and insulation of the top walls are further investigated to obtain ideas for the efficient use of the insulation material. The new characterization scheme proves to be an efficient tool to rank the performance of different boundary designs during storing process of large-scale stratified hot water heat stores and to provide valuable design insights.
Interfraction patient motion and implant displacement in prostate high dose rate brachytherapy
Authors: Fox C. D. , Kron T. , Leahy M. , Duchesne G. , Williams S. , Tai K. H. , Haworth A. , Herschtal A. , Foroudi F.
Published: October 2011

Purpose:

To quantify movement of prostate cancer patients undergoing treatment, using an in‐house developed motion sensor in order to determine a relationship between patient movement and high dose rate (HDR) brachytherapy implant displacement.

Methods:

An electronic motion sensor was developed based on a three axis accelerometer. HDR brachytherapy treatment for prostate is delivered at this institution in two fractions 24 h apart and 22 patients were monitored for movement over the interval between fractions. The motion sensors functioned as inclinometers, monitoring inclination of both thighs, and the inclination and roll of the abdomen. The implanted HDR brachytherapy catheter set was assessed for displacement relative to fiducial markers in the prostate. Angle measurements and angle differences over a 2 s time base were binned, and the standard deviations of the resulting frequency distributions used as a metric for patient motion in each monitored axis. These parameters were correlated to measured catheter displacement using regression modeling.

Results:

The mean implant displacement was 12.6 mm in the caudal direction. A mean of 19.95 h data was recorded for the patient cohort. Patients generally moved through a limited range of angles with a mean of the exception of two patients who spent in excess of 2 h lying on their side. When tested for a relationship between movement in any of the four monitored axes and the implant displacement, none was significant.

Conclusions:

It is not likely that patient movement influences HDR prostate implant displacement. There may be benefits to patient comfort if nursing protocols were relaxed to allow patients greater freedom to move while the implant isin situ.
Phosphorylation of Mad Controls Competition Between Wingless and BMP Signaling
Authors: Eivers Edward , Demagny Hadrien , Choi Renee H. , De Robertis Edward M.
Published: October 2011

The transcription factor Mad participates in two different developmentally important signaling pathways depending on its phosphorylation status.
A Raft to Insulin Resistance?
Authors: Adler Elizabeth M.
Published: October 2011

Saturated fatty acids promote redistribution of c-Src into detergent-resistant membrane fractions, thereby stimulating JNK activation.
Elevated Cell Wall Chitin in Candida albicans Confers Echinocandin Resistance
In Vivo
Authors: Lee Keunsook K. , MacCallum Donna M. , Jacobsen Mette D. , Walker Louise A. , Odds Frank C. , Gow Neil A. R. , Munro Carol A.
Published: October 2011

Candida albicans
cells with increased cell wall chitin have reduced echinocandin susceptibility
in vitro
. The aim of this study was to investigate whether
C. albicans
cells with elevated chitin levels have reduced echinocandin susceptibility
in vivo
. BALB/c mice were infected with
C. albicans
cells with normal chitin levels and compared to mice infected with high-chitin cells. Caspofungin therapy was initiated at 24 h postinfection. Mice infected with chitin-normal cells were successfully treated with caspofungin, as indicated by reduced kidney fungal burdens, reduced weight loss, and decreased
C. albicans
density in kidney lesions. In contrast, mice infected with high-chitin
C. albicans
cells were less susceptible to caspofungin, as they had higher kidney fungal burdens and greater weight loss during early infection. Cells recovered from mouse kidneys at 24 h postinfection with high-chitin cells had 1.6-fold higher chitin levels than cells from mice infected with chitin-normal cells and maintained a significantly reduced susceptibility to caspofungin when tested
in vitro
. At 48 h postinfection, caspofungin treatment induced a further increase in chitin content of
C. albicans
cells harvested from kidneys compared to saline treatment. Some of the recovered clones had acquired, at a low frequency, a point mutation in
FKS1
resulting in a S645Y amino acid substitution, a mutation known to confer echinocandin resistance. This occurred even in cells that had not been exposed to caspofungin. Our results suggest that the efficacy of caspofungin against
C. albicans
was reduced
in vivo
due to either elevation of chitin levels in the cell wall or acquisition of
FKS1
point mutations.
Interplay between the Gastric Bacterial Microbiota and Candida albicans during Postantibiotic Recolonization and Gastritis
Authors: Mason Katie L. , Erb Downward John R. , Falkowski Nicole R. , Young Vincent B. , Kao John Y. , Huffnagle Gary B.
Published: October 2011

The indigenous bacterial microbiome of the stomach, including lactobacilli, is vital in promoting colonization resistance against
Candida albicans
. However, there are gaps in our understanding about
C. albicans
gastric colonization versus disease, especially during the postantibiotic recovery phase. This study compared the gastric responses to
C. albicans
strains CHN1 and SC5314 in microbiome-disturbed and germfree mice to elucidate the contribution of the indigenous microbiota in
C. albicans
colonization versus disease and yeast-bacterium antagonism during the post-cefoperazone recolonization period.
C. albicans
can prevent the regrowth of
Lactobacillus
spp. in the stomach after cefoperazone and promote increased colonization by
Enterococcus
spp. Using a culture-independent analysis, the effects of oral cefoperazone on the gastric bacterial microbiota were observed to last at least 3 weeks after the cessation of the antibiotic. Disturbance of the gastric bacterial community by cefoperazone alone was not sufficient to cause gastritis,
C. albicans
colonization was also needed. Gastritis was not evident until after day 7 in cefoperazone-treated infected mice. In contrast, in germfree mice which lack a gastric microbiota,
C. albicans
induced gastric inflammation within 1 week of inoculation. Therefore, the gastric bacterial community in cefoperazone-treated mice during the first week of postantibiotic recolonization was sufficient to prevent the development of gastritis, despite being ineffective at conferring colonization resistance against
C. albicans
. Altogether, these data implicate a dichotomy between
C. albicans
colonization and gastric disease that is bacterial microbiome dependent.
The Staphylococcus aureus Two-Component Regulatory System, GraRS, Senses and Confers Resistance to Selected Cationic Antimicrobial Peptides
Authors: Yang Soo-Jin , Bayer Arnold S. , Mishra Nagendra N. , Meehl Michael , Ledala Nagender , Yeaman Michael R. , Xiong Yan Q. , Cheung Ambrose L.
Published: October 2011

The two-component regulatory system, GraRS, appears to be involved in staphylococcal responses to cationic antimicrobial peptides (CAPs). However, the mechanism(s) by which GraRS is induced, regulated, and modulated remain undefined. In this study, we used two well-characterized MRSA strains (Mu50 and COL) and their respective mutants of
graR
and
vraG
(encoding the ABC transporter-dependent efflux pump immediately downstream of
graRS
), and show that (i) the expression of two key determinants of net positive surface charge (
mprF
and
dlt
) is dependent on the cotranscription of both
graR
and
vraG
, (ii) reduced expression of
mprF
and
dlt
in
graR
mutants was phenotypically associated with reduced surface-positive charge, (iii) this net reduction in surface-positive charge in
graR
and
vraG
mutants, in turn, correlated with enhanced killing by a range of CAPs of diverse structure and origin, including those from mammalian platelets (tPMPs) and neutrophils (hNP-1) and from bacteria (polymyxin B), and (iv) the synthesis and translocation of membrane lysyl-phosphatidylglycerol (an
mprF
-dependent function) was substantially lower in
graR
and
vraG
mutants than in parental strains. Importantly, the inducibility of
mprF
and
dlt
transcription via the
graRS-vraFG
pathway was selective, with induction by sublethal exposure to the CAPs, RP-1 (platelets), and polymyxin B, but not by other cationic molecules (hNP-1, vancomycin, gentamicin, or calcium-daptomycin). Although
graR
regulates expression of
vraG
, the expression of
graR
was codependent on an intact downstream
vraG
locus. Collectively, these data support an important role of the
graRS
and
vraFG
loci in the sensing of and response to specific CAPs involved in innate host defenses.
Temporal trends in bird abundance in response to thinning of lodgepole pine (Pinus contorta)
Authors: Bayne Erin , Nielsen Bruce
Published: October 2011

Forest managers are continually seeking methods of extracting more timber from the land base while maintaining appropriate wildlife habitat. A 7-year before–after control–impact (BACI) experiment was conducted in 60-year-old lodgepole pine (Pinus contorta Douglas ex Loudon) to determine the effects of thinning on forest birds. One year of pretreatment data was compared with 6 years of posttreatment data. Using linear trend analysis corrected for detection error, we found that Chipping Sparrow (Spizella passerina (Bechstein, 1798)), Dark-eyed Junco (Junco hyemalis (Linnaeus, 1758)), and Red-eyed Vireo (Vireo olivaceus (Linnaeus, 1766)) increased over time in thinned stands and declined in control stands. Alder Flycatcher (Empidonax alnorum Brewster, 1895), Hermit Thrush (Catharus guttatus (Pallas, 1811)), Rose-breasted Grosbeak (Pheucticus ludovicianus (Linnaeus, 1766)), and Blue-headed Vireo (Vireo solitarius (Wilson, 1810)) decreased in control and thinned stands but declined more in controls. Varied Thrush (Ixoreus naevius (J. F. Gemlin, 1789)) and White-winged Crossbill (Loxia leucoptera Gemlin, 1789) increased in control stands relative to thinned areas, where they were stable or declined. A significant interaction between treatment and year was observed for 24 species when year was categorical. Of these, species more likely found in control stands were Boreal Chickadee (Poecile hudsonicus (J.R. Forster, 1772)), Golden-crowned Kinglet (Regulus satrapa Lichtenstein, 1823), and Least Flycatcher (Empidonax minimus (W.M. Baird & S.F. Baird, 1843)), whereas Ruffed Grouse (Bonasa umbellus (Linnaeus, 1766)), Tennessee Warbler (Vermivora peregrina (A. Wilson, 1811)), and Warbling Vireo (Vireo gilvus (Vieillot, 1808)) were more likely in thinned stands. Total bird abundance was higher in thinned stands, which is consistent with 83% of thinning studies in western coniferous forests. Thinning can be a useful tool for achieving wildlife management goals and increasing timber yields.
Understanding soil nutrients and characteristics in the Pacific Northwest through parent material origin and soil nutrient regimes
Authors: Littke K.M. , Harrison R.B. , Briggs D.G. , Grider A.R.
Published: October 2011

A convenient method is necessary for assessing the availability of soil nitrogen in plantation Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stands in the Pacific Northwest. The objective of this research was to use soil parent materials (SPMs) and soil nutrient regimes (SNRs) to determine the most efficient method to characterize soil nitrogen availability in Douglas-fir stands. It was hypothesized that SPMs and SNRs would effectively separate stands with distinctive climate, site, and soil characteristics and forest floor and soil carbon and nitrogen reserves. At 60 Douglas-fir stands, SPMs and SNRs were determined, and soil particle percentages, soil depth, and forest floor and soil nitrogen and carbon contents were measured to a depth of 1 m. Soils of sedimentary origin and very rich and rich SNRs contained greater nitrogen and carbon contents than those from glacial and igneous origins and medium SNRs. Sedimentary SPMs and very rich SNRs were developed from older parent materials and had significantly greater soil depths and finer textures than those from glacial SPMs and medium SNRs. SNRs and SPMs are recommended as good estimators of soil nutrient pools and soil characteristics in Douglas-fir plantation forests of the Pacific Northwest.
Photosynthetic production of ground vegetation in different-aged Scots pine (Pinus sylvestris) forests
Authors: Kulmala L. , Pumpanen J. , Kolari P. , Muukkonen P. , Hari P. , Vesala T.
Published: October 2011

The photosynthesis of ground vegetation is dependent on species composition and environmental factors that are extremely diverse during forest succession. However, present in situ measurements over the gross primary production (GPP) of ground vegetation are unable to cover this variability. The primary objective of the present study was to estimate the GPP of ground vegetation in five differently aged Scots pine (Pinus sylvestris L.) forests in southern Finland during the growing season of 2006 by using temperature, soil moisture, photosynthetically active radiation, and biomass of the ground vegetation to run a known process-based model. The GPP of ground vegetation was ~350 g·m–2 at the 6- and 12-year-old sites and 168, 146, and 41 g·m–2 thereafter at the 20-, 45-, and 120-year-old sites, respectively. The values decreased with stand age, because as the stand ages, light availability decreases, the dominant species below the canopy show lower rates of photosynthesis than species in open areas, and the biomass of the ground vegetation decreases. Grasses and herbs took up nearly half of the value at the youngest site but their role decreased thereafter, whereas low shrubs were responsible for most of the GPP of ground vegetation below closed canopies.
Ranking of four contributions to error in stand-level Douglas-fir log supply and value recovery estimation
Authors: Murphy Glen E. , Acuna Mauricio A.
Published: October 2011

Sustainability and globally competitive forest product supply markets are two of the pressures that forest managers face today. Both require that managers have good metrics of the quantity, quality, and location of timber resources within their forests. The value of this information must be weighed against the cost of obtaining it and losses associated with not having access to it. A cost-plus-loss procedure for assessing the relative contributions to error in estimating stand-level value recovery and log product yields was developed and tested on two Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco) stands in Oregon. The sources of error were those associated with (i) market complexity, (ii) sampling intensity, (iii) stem quality assessment methods, and (iv) bucking optimization algorithms. Two performance measures were used as part of the assessment procedure: market fulfilment and the difference in total net value recovery between having complete and less than complete information. Average market fulfilment ranged between 60% and 100%. The difference in total net value recovery ranged from –21.2% to +0.8%. Stem quality assessment followed by bucking optimization algorithms and sampling intensity had the greatest effects on these performance measures. Market complexity had a negligible effect on these performance measures but affected net value recovery.
CSCORE: A SIMPLE YET EFFECTIVE SCORING FUNCTION FOR PROTEIN–LIGAND BINDING AFFINITY PREDICTION USING MODIFIED CMAC LEARNING ARCHITECTURE
Authors: OUYANG XUCHANG , HANDOKO STEPHANUS DANIEL , KWOH CHEE KEONG
Published: October 2011

Protein–ligand docking is a computational method to identify the binding mode of a ligand and a target protein, and predict the corresponding binding affinity using a scoring function. This method has great value in drug design. After decades of development, scoring functions nowadays typically can identify the true binding mode, but the prediction of binding affinity still remains a major problem. Here we present CScore, a data-driven scoring function using a modified Cerebellar Model Articulation Controller (CMAC) learning architecture, for accurate binding affinity prediction. The performance of CScore in terms of correlation between predicted and experimental binding affinities is benchmarked under different validation approaches. CScore achieves a prediction with R = 0.7668 and RMSE = 1.4540 when tested on an independent dataset. To the best of our knowledge, this result outperforms other scoring functions tested on the same dataset. The performance of CScore varies on different clusters under the leave-cluster-out validation approach, but still achieves competitive result. Lastly, the target-specified CScore achieves an even better result with R = 0.8237 and RMSE = 1.0872, trained on a much smaller but more relevant dataset for each target. The large dataset of protein–ligand complexes structural information and advances of machine learning techniques enable the data-driven approach in binding affinity prediction. CScore is capable of accurate binding affinity prediction. It is also shown that CScore will perform better if sufficient and relevant data is presented. As there is growth of publicly available structural data, further improvement of this scoring scheme can be expected.
FIXED POINT THEOREMS FOR GENERAL CLASSES OF MAPS ACTING ON TOPOLOGICAL VECTOR SPACES
Authors: Agarwal Ravi P. , O'Regan Donal , Taoudi Mohamed-Aziz
Published: October 2011

We present new fixed point theorems for multivalued [Formula: see text]-admissible maps acting on locally convex topological vector spaces. The considered multivalued maps need not be compact. We merely assume that they are weakly compact and map weakly compact sets into relatively compact sets. Our fixed point results are obtained under Schauder, Leray–Schauder and Furi-Pera type conditions. These results are useful in applications and extend earlier works.
Radial basis function neural network based approach to test oracle
Authors: Sangwan Om Prakash , Bhatia Pradeep Kumar , Singh Yogesh
Published: October 2011

Software testing is an important discipline, and consumes significant amount of effort. A proper strategy is required to design and generate test cases systematically and effectively. In this paper automated software test case generation with Radial Basis Function Neural Network (RBFNN) has been proposed and empirically validated with the help of a case study and compared with other techniques of soft computing. Experimental results show that RBFNN is one of the best technique for automated test case generation.
The 7% rule
Authors: Yaffe Philip
Published: October 2011

In 1971, Albert Mehrabian published a book
Silent Messages
, in which he discussed his research on non-verbal communication. He concluded that prospects based their assessments of credibility on factors other than the words the salesperson spoke---the prospects studied assigned 55 percent of their weight to the speaker's body language and another 38 percent to the tone and music of their voice. They assigned only 7 percent of their credibility assessment to the salesperson's actual words. Over the years, this limited experiment evolved to a belief that movement and voice coaches would be more valuable to teaching successful communication than speechwriters. In fact, in 2007 Allen Weiner published
So Smart But…
discussing how to put this principle to work in organizations.
Competitive Nanotechnology for Deposition of Films and Fabrication of Powder-Like Particles
Authors: Khoperia Teimuraz , Mamniashvili Grigor , Nadareishvili Malkhaz , Zedginidze Tinatin
Published: October 2011

The competitive method of fabrication of thermo-absorbing meso- and nanosized magnetic particles was developed. Applications of high-dispersive magnetic particles could include information storage systems, biomedical fields, targeted delivery of drugs for cancer treatment, sensors, etc. By means of electroless deposition of nanoclusters on high-dispersive powder-like semiconductor TiO2 (anatase), some problems of fabrication of visible light-responsive photocatalysts are overcome or mitigated. A new method of size selection of pure TiO2 particles and micro-, meso- and nanocrystal-coated powder-like semiconductor photocatalysts with aim obtain of a uniform size distribution was developed. Catalysts Pd/γ-Al2O3, reduced in hydrogen flow, compare well with platinum catalysts by the activity in relation to breaking of bonds between carbons.
The α-Si/SiGe Core/Shell Nano-Wire as Highly Sensitive Bio-Sensor
Authors: Chang Kow-Ming , Chen Chu-Feng , Lai Chiung-Hui , Liu Chung-Hsien , Wang Yu-Bin , Wu Chin-Ning , Hsieh Cheng-Ting
Published: October 2011

Reducing the width of a nano-wire increases its surface to volume ratio, increasing the sensitivity of its conductivity to charges on its surface. Our previous studies have shown that increasing the Ge fraction in Si1-xGex nano-wires improves their sensitivity as bio-sensing. In this work, an α-Si/SiGe core/shell nano-wire is successfully fabricated using side-wall spacer method. The maximum sensitivity of a nano-wire bio-sensor with an optimizedα-Si/SiGe thickness ratio is investigated.
Electrochemical Stabilization of Prussian Blue Films in NH4Cl Aqueous Medium
Authors: Agrisuelas Jerónimo , Delgado Carla , Gabrielli Claude , García-Jareño José Juan , Perrot Hubert , Vicente Francisco
Published: October 2011

Derivative voltabsommetric scans in near-UV/visible-NIR electromagnetic range together with nano-electrogravimetric measurements during the stabilization process of Prussian Blue in NH4Cl aqueous solution yields information about the localization of the into the crystalline structure of this material. It is proposed that the ammonium ion is placed into the vacancies of the framework that affect to the motional resistance. The simultaneous measure of current, mass, motional resistance, and near-UV-vi-N IR spectra allows to explain the differences observed between the Prussian Blue films placed in a solution of NH4Cl salt regarding the behaviour showed in KCl aqueous solution.
Recession and Characterization of Patterned Nanowires Grown by Electroless Etching of Silicon
Authors: Mertens Robert G. , Sundaram Kalpathy B.
Published: October 2011

Abstract-Silicon nanowires (SiNWs) were grown by the electroless etching technique using silver nitrate (AgNO3)/hydrofluoric acid (HF) solution on a patterned p-type Silicon (Si) substrate with varying etching times. The various etch times produced different recession depths wherever the pattern allowed the etching solution to contact the Silicon substrate. At the bottom of each recession, SiNWs were produced of varying length and size, according to the depth of the recession. In this type of growth procedure, SiNWs are grown but the tips are etched away. SiNWs grown by this method tend to agglomerate or bunch at their tips.
Corrosion Behavior of Cr(Si)N/301 Stainless Steel System
Authors: Azzi Marwan , Klemberg-Sapieha Jolanta-Ewa , Martinu Ludvik
Published: October 2011

In this paper, the electrochemical behavior of Cr(Si)N coatings deposited on AISI 301 stainless steel (SS) substrate is investigated. Cr(Si)N films with different Si contents were prepared by dual magnetron sputtering. Potentiodynamic polarization measurements were carried out in NaCl 1% solution to evaluate resistance to localized and general corrosion. These measurements were performed on Cr(Si)N coatings deposited on SS and glass substrates, using a customized electrochemical cell, with the purpose to determine the contribution of SS to the electrochemical response of the coating/SS system. The morphology, composition and microstructure of the surface layers were examined by complementary characterization techniques including XRD, ERD, and SEM. It has been shown that the Cr(Si)N coatings improved significantly the pitting resistance of SS with not pits observed up to 1000 mV anodic polarization as compared to bare SS where the pitting potential was 330 mV. Moreover, the polarization curves of the coated SS exhibited passive-transpassive behavior with slight improvement in the corrosion properties as Si content is increased. This response is the result of electrochemical reactions at the Cr(Si)N/electrolyte interface as demonstrated by the polarization measurements on the coating/glass system.
Replacement of Au and Ag with the Ni-P and Ni-B Alloys in Electronics
Authors: Khoperia Teimuraz
Published: October 2011

A new method of production of precise piezoelectric quartz resonators and filters, and monolithic piezoquartz filters with electrodes, made of electroless nickel-phosphorous alloy, for spacecraft, hydroacoustics and communication devices was developed. Electrical characteristics of quartz resonators with the deposited Ni-P coating are better than when gold and silver were used as electrode layers. A method of electroless deposition on polished quartz, glass and other nonmetallic polished materials was developed. Bulk and miniature resonators of piezoquartz and lithium niobate manufactured on the basis of the developed technology of electroless deposition of a nickel-phosphorus alloy, instead of gold and silver plating, were successfully used in industry. The technology was developed for the production of piezoceramic and ceramic devices by electroless deposition of electrode layers made of Ni-P or Cu.
Conductometric Analysis for the Formation of Poly(Vinylidene Fluoride)-Based Ion Track Membranes
Authors: Yamaki Tetsuya , Nuryanthi Nunung , Koshikawa Hiroshi , Asano Masaharu , Sawada Shin-ichi , Hasegawa Shin , Maekawa Yasunari , Voss Kay-Obbe , Trautmann Christina , Neumann Reinhard
Published: October 2011

Poly(vinylidene fluoride) (PVDF) films were irradiated with 450 MeV 129Xe and 2.2 GeV 197Au ion beams and then the resulting latent tracks were etched in a 9 mol dm-1 aqueous KOH solution at 80ºC poured into an conductometry cell. At the same time, the evolution of cylindrical nanopores was monitored by measuring the conductance through the membrane. This in-situ measurement enabled us to examine how etching kinetics were affected by various experimental conditions, e.g., the parameters (mass and velocity) of the bombarded ions and cell potentials applied between the electrodes. The track etch rate, VT, radial rate, VR, and pore radius reaching the final plateau strongly depended on the deposited energy within each track, which is represented by the linear energy transfer (LET). Interestingly, applying a higher voltage to the cell promoted track etching up to breakthrough probably because electrophoretic migration of dissolved products occurred out of each pore.
Theoretical Study on Chemical Degradation Mechanism of Nafion Side Chain by the Attack of OH Radical in Polymer Electrolyte Fuel Cell
Authors: Ishimoto Takayoshi , Ogura Teppei , Koyama Michihisa
Published: October 2011

We theoretically analyzed the chemical degradation mechanism of Nafion side chain by OH radical on the basis of density functional theory calculations. We found the C-O bond cleavage in the ether group by the OH radical induces the degradation of Nafion from side chain under well-hydrated condition. The ether group, which is located near sulfo group, is vulnerable to OH radical attack rather than the other ether group connecting the side chain with the main chain.
Beyond Oil and Gas: The Methanol Economy
Authors: Prakash G. K. Surya , Olah George , Goeppert Alain
Published: October 2011

Nature's photosynthesis uses the sun's energy with chlorophyll in plants as a catalyst to recycle carbon dioxide and water into new plant life. Only given sufficient geological time can new fossil fuels be formed naturally. Today, anthropogenic CO2 emissions, mainly from the burning of fossil fuels, also far outpace nature's CO2 recycling capabilities, contributing significantly to the current global warming problem. To supplement and dramatically accelerate the natural CO2 recycling process, chemical recycling of carbon dioxide from natural and industrial sources as well as varied human activities or even from the air itself to methanol or dimethyl ether (DME) and their varied products including hydrocarbons can be achieved via its capture and subsequent reductive conversion in the framework of the Methanol Economy.
The Regularities of Electrolytic Dissociation of 1,2-Cyclopropanedicarboxylic Acids
Authors: Kvaratskhelia Elene , Kvaratskhelia Ramaz
Published: October 2011

The dissociation parameters for the dilute (0.0001-0.01M) solutions of cis and trans-1,2-cyclopropanedicarboxylic acids were calculated with the aid of the new original method for analysis the regularities of electrolytic dissociation of weak multibasic organic acids with the effect of "overlapping" equilibria. The equations for determination the regions of predominance of various charged and uncharged forms of these acids were also described.
Evaluation and Modeling of a Photo-Electrochemical Reactor for Hydrogen Production Operating under High Photon Flux
Authors: Ong Chin Kin , Dennison Stephen , Hellgardt Klaus , Kelsall Geoff
Published: October 2011

A photo-electrochemical reactor for water splitting with a Si(IV)-doped Fe2O3 photoanode was designed to investigate the effects on photocurrent densities of electrode potential, photon flux and 'front' and 'back' illumination of the photoanode. As a design tool to optimize the reactor performance, a 1-D kinetic model incorporating photogeneration, diffusion, migration, recombination and surface reaction terms, was developed to predict minority carrier concentration profiles and hence photocurrent densities. Model predictions were in good agreement with experimental photocurrent densities, which increased linearly with increased light intensity. Photocurrent densities decreased by 90 % when the direction of illumination was switched from hν -> electrolyte | semiconductor to hν -> glass | fluorinated tin oxide | semiconductor | electrolyte, due to the resulting decrease in hole concentrations at the semiconductor | liquid junction.
The Evaluation of Triphenyl Phosphate as A Flame Retardant Additive to Improve The Safety of Lithium-Ion Battery Electrolytes
Authors: Smart Marshall C. , Krause Frederick C. , Hwang Constanza , West William C. , Soler Jessica , Prakash G. K. Surya , Ratnakumar Bugga V.
Published: October 2011

With the intent of improving the safety characteristics of lithium-ion cells, electrolytes containing flame retardant additives have been investigated. A number of triphenyl phosphate (TPP)-containing electrolytes were evaluated in both coin cells and experimental three electrode lithium-ion cells (containing reference electrodes). A number of chemistries were investigated, including MCMB carbon/LiNi0.8Co0.2O2 (NCO), graphite/ LiNi0.8Co0.15Al0.05O2 (NCA), Li/Li(Li0.17Ni0.25Mn0.58)O2, Li/LiNiMnCoO2 (NMC) and graphite/LiNiMnCoO2 (NMC), to study the effect that different electrolyte compositions have upon performance. A wide range of TPP-containing electrolytes were demonstrated to have good compatibility with the C/NCO, C/NCA, and Li/NMC systems, however, poor performance was initially observed with the high voltage C/NMC system. This necessitated the development of improved electrolytes with stabilizing additives, leading to formulations containing lithium bis(oxalato)borate (LiBOB) that displayed substantially improved performance
Electrochemical Oxidation of NADH in L-Cysteine Monolayer on Palladium Surface
Authors: Feliciano-Ramos Ileana , Cabrera Carlos R.
Published: October 2011

The electrochemical oxidation of NADH has been evaluated using palladium surface modified with self assembled monolayer of L-cysteine. The alcohol dehydrogenase (ADH) enzyme was immobilized onto L-cysteine monolayer using different routes; adsorption physical or entrapment of the enzyme using Nafion as polymer. These modifications were analyzed with Fourier transform infrared (FT-IR) spectroscopy and electrochemical techniques. The FT-IR was used to characterize the immobilization process of ADH in L-cysteine monolayer. In cyclic voltammetry we use a redox probe as Fe(CN)63-/4- in KNO3 for study the kinetic of the system. Also, we studied the electrochemical oxidation of NADH in bare palladium and Pd modified with L-cysteine monolayer. The results show that L-cysteine monolayer assembly on the electrode surface facilitates the NADH oxidation, allowing the oxidation at a less positive potential. Finally, we studied the electrocatalytic activity toward the oxidation of ethanol in presence of ADH immobilized at L-cysteine monolayer and NAD+ in solution for the detection NADH on the palladium surface.
General Feature Profile Simulator FPS-3D
Authors: Moroz Paul
Published: October 2011

FPS-3D is a Monte Carlo code designed for simulation of 2D and 3D feature profile evolution. The Monte Carlo particles, launched in correspondence with specified fluxes, interact with solid materials of the target. Each particle typically consists of many gas molecules, or ions, or electrons. A cellular model is used for presenting solid materials. FPS-3D is a general code in a sense that it can be applied to any geometry, any materials, any fluxes, and any set of reactions. All properties of materials and all reactions are specified separately in the chemistry file, while geometry, fluxes, and other parameters are specified in the input file and, if necessary, in the flux file. Predictive capability of FPS-3D comes from its ability to produce results in agreement with experiments for a wide range of conditions while using the same chemistry file. A case of Si and SiO2 etching in Cl/Ar-plasma is used for the demonstration.
Effect of Chain Length Compatibility between Surfactants and Co-Surfactants on Corrosion Inhibition of Steel
Authors: Asefi Dourna , Arami Mokhtar , Mahmoodi Niyaz Mohammad
Published: October 2011

Corrosion inhibition effect of cationic surfactants, DTAB (Dodecyl Three methyl Ammonium Bromide) and TTAB (Tetradecyl Three methyl Ammonium Bromide) on low carbon steel was studied using weight loss, Open circuit potentional (OCP) and Electrochemical Impedance Spectroscopy (EIS) measurements. The effect of chain length compatibility on corrosion inhabitancy of surfactant and co-surfactant was investigated by C7OH (1-heptanol), C12OH (1-dodecanol) and C15OH (1-pentadecanol) as nonionic co-surfactants in acidic media at different concentrations of DTAB and TTAB. Data represented that the corrosion rate decreased by increasing concentration of DTAB and TTAB, independently. The effect of chain length compatibility on surfactant behavior was discussed. Decreasing of corrosion rate for DTAB+C12OH was more pronounced than other mixtures.
Electropolymerized Ultrathin Chromophore Films for VOC Sensing
Authors: Paske Amanda C. , Gunsch Matthew J. , O'Donnell Jodi L.
Published: October 2011

Porphyrin containing thin film colorimetric sensors for volatile organic compounds (VOCs) have been synthesized and characterized. Electropolymerization has been employed to synthesize robust poly-tetrakis(4-aminophenyl)porphyrin films. Production of films by this method allows for fine control over thickness allowing for rapid responses to analytes. While many techniques used to produce thin films rely on electrostatics, these films are covalently linked, yielding excellent structural integrity upon repeated exposure to organic solvents. Several transition metals have been inserted into the porphyrin films to modulate the sensory response based upon the affinity of particular transition metals to organic analytes.
Effect of Annealing on the Optical Characteristics of Electrodeposited <002>-Oriented CuO Thin Films
Authors: Nagai Miho , Mizushima Yuya , Binti Mohamad Fariza , Sasano Junji , Izaki Masanobu
Published: October 2011

The p-type semiconductor CuO has attracted increasing attention as the light-absorbing layer in photovoltaic devices, due to the bandgap energy appropriate to the application. This paper reports the preparation of the (002)-oriented and excellent photoactive CuO films prepared by electrodeposition in a basic aqueous solution followed by annealing. The annealing under optimized condition gave the improvement of both the crystallinity and photoactivity including the response and photocurrent density. The annealed CuO film is a potential candidate as the light absorbing layer of next generation thin film photovoltaic devices.
Confinement Effects on the Thermal and Conductivity Properties of LiPF6-Dimethyl Carbonate Solutions Relevant to Lithium Rechargeable Batteries
Authors: Butson Eric D. , Atchley Justin , Burba Christopher
Published: October 2011

Solutions of lithium hexafluorophosphate dissolved in dimethyl carbonate (DMC) are confined within a nano-porous silica matrix (MCM-41). Thermal measurements indicate that the melting points of pure DMC and a 1.0 m LiPF6 DMC solution are significantly reduced when confined within the nanopores compared to bulk samples; an observation that is consistent with the Gibbs-Thompson equation. Temperature-dependent conductivity measurements of the confined solution show a sharp decrease in solution conductivity between 0 and -10oC. The measured conductivity values below -10oC are not sufficient to operate a lithium ion battery at sub-zero temperatures.
Light Emitting Diodes Formed Using Mist Deposition of Colloidal Solution of CdSe Nanocrystalline Quantum Dots
Authors: Kshirsagar Aditya , Pickering Shawn , Xu Jian , Ruzyllo Jerzy
Published: October 2011

This study is concerned with the fabrication of multi-color Light-Emitting Diodes (LEDs) using colloidal solutions of CdSe Nanocrystalline Quantum Dots (NQDs) by the process of mist deposition. CdSe/ZnS core/shell NQDs with red (620 nm), yellow (587 nm) and green (558nm) emissions were deposited to form a patterned tri-color array of quantum dot LEDs. Results obtained from simulation studies show the correlation between the drop size of mist deposition process and the thickness of the resulting NQD films as well as extent of area coverage with mist deposited quantum dots.