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Constant Increase (constant + increase)
Kinds of Constant Increase Selected AbstractsMechanical behavior of bovine periodontal ligament under tension-compression cyclic displacementsEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 1 2006Tatsuya Shibata In the present study, the mechanical response of bovine periodontal ligament (PDL) subjected to displacement-controlled tension,compression harmonic oscillations and subsequent rupture was examined. Specimens including dentine, cementum, PDL, and alveolar bone were extracted from different depths and locations of bovine first molars. They were immersed in a saline solution at room temperature and clamped on their bone and dentine extremities. The samples were tested at ±35% of the PDL's width, with a frequency of 1 Hz. The mechanical parameters evaluated were hysteresis, phase lag, and the modulus of the stress,stretch ratio curves in tension and compression. The tensile strength and the corresponding stretch ratio were also recorded. Stress,stretch ratio curves indicated a non-linear, time-dependent response with hysteresis and preconditioning effects. The hysteresis and phase lag in compression were much higher than in tension, suggesting that the dissipated energy was higher in compression than in tension. The root depth and location did not play essential roles for the tension or compression data, with the exception of limited statistical differences for tensile strength and corresponding stretch ratio. Thus, biological variability in the specimens, as a result of different bone contours, PDL width, and fiber orientation, did not affect the energy-absorbing capacity of the PDL. The evolution of the stress rate with stress demonstrated a constant increase of stiffness with stress. The stiffness values were twofold higher in tension than in compression. The data also showed that the stiffness of the PDL was comparable with data reported for other soft tissues. [source] Synthesis of Cyclic Peptides by Photochemical Decarboxylation of N -Phthaloyl Peptides in Aqueous SolutionHELVETICA CHIMICA ACTA, Issue 12 2002The synthesis of a variety of cyclic peptides from N -phthaloyl-protected di-, tri-, tetra-, and pentapeptides with different aminocarboxylic acid tethers by photodecarboxylation , initiated by intramolecular electron transfer , has been explored in aqueous media. The progress and the chemoselectivity of the follow-up processes after CO2 extrusion were traced by the respective pH/time-profiles, as well as by the overall change in pH after completion of the reaction. The competition between cyclization and simple oxidative decarboxylation depends on spacer length and geometry, H-bonding interaction between the electron accepting phthalimide CO groups and amide H-atoms, as well as the geometric reorganization coupled with the radical combination step and the formation of the lactam rings. With progressing reaction, hydrolysis of the phthalimide chromophore becomes an increasingly important side reaction due to the constant increase in pH. The use of phosphate-buffered aqueous media consequently improved the cyclization yields. The ground-state interactions between amide groups and the terminal COO, group with the imide CO groups were studied for the model system [N -(phthaloyl)glycyl]sarcosine (1) by NMR spectroscopy where the amide (E/Z)-equilibrium depends on the presence of carboxylate vs. free carboxylic acid, demonstrating the role of H-bonding and metal coordination. [source] Higher Education in Germany: a Case of ,Uneven' Expansion?HIGHER EDUCATION QUARTERLY, Issue 3 2005Hubert Ertl This paper investigates the expansion of student numbers in higher education (HE) in Germany. The quantitative sources indicate a constant increase in student numbers in the 1990s, but show that this growth was uneven and differentiated. The paper discusses a number of factors that influenced the increases in student numbers since the early 1990s, including the opening up and restructuring of HE in eastern Germany, and the strong increases in female participation and in the number of international students. Growth has been particularly significant in certain subject areas, as well as at Fachhochschulen and at private HE institutions. Current developments regarding the introduction of tuition fees and changing structures regarding access to HE are outlined, and their impact on the future expansion of HE is discussed. [source] Assessing spatial variation in browsing history by means of fraying scarsJOURNAL OF BIOGEOGRAPHY, Issue 6 2004Bruno Vila Abstract Aim, We used fraying scars to understand spatial variation in browsing history. Information on browsing history is an essential background in studies on the long-term effect of deer browsing on the flora and fauna and of its variation in space. Location, We focused on two small neighbouring islands of Haida Gwaii (British Columbia, Canada), Reef Island and South-Skedans Island, colonized by introduced black-tailed deer (Odocoileus hemionus sitkensis). Methods, We searched for sites where trees with fraying scars were clustered. We studied the trees that deer selected (species, size) and the characteristics of scars (number, position, size). Using a cross-dating procedure, we dated fraying scars with dendrochronology, obtaining an accurate estimate of the year the scar was formed. Results, On Reef Island, Thuja plicata was the tree species chosen for fraying. On South-Skedans Island, where Thuja plicata is missing, deer chose Salix sp. and Alnus rubra. Deer chose only trees with a circumference of less than 50 cm. About two to three fraying scars were recorded per tree. All of them extended between 30,40 and 70,80 cm from the ground and were between 5 and 6 cm in width. On Reef Island, 95% of the scars were formed during the last 50 years. On South-Skedans Island, 95% were formed over the last 10 years. Age distribution of scars showed a constant increase of the number of scars over time. It indicated that deer had colonized Reef Island 53 years prior to this study but were absent or rare on South-Skedans Island until 13 years prior to this study. Main conclusions, These results indicate different colonization dates and thus different length of browsing histories for the islands studied and provide the historical background necessary to analyse the involvement of deer in the current differences in the flora and fauna observed between islands. [source] Malaria Epidemiological Situation in Italy and Evaluation of Malaria Incidence in Italian TravelersJOURNAL OF TRAVEL MEDICINE, Issue 1 2001Roberto Romi Background: Malaria was endemic throughout the country until it was eradicated nearly 50 years ago. Since then, mainly imported malaria cases have been reported to the National Health Service, with an increasing trend. The aim of this study was to present a detailed analysis of the current epidemiological situation of malaria in Italy, and to make a first attempt to calculate the incidence of malaria in Italian international travelers. Methods: An archive of confirmed malaria cases is available at the Istituto Superiore di Sanitį (ISS), the National Institute of Health of Italy, based on the mandatory report system. Data from each case report reported to the ISS from 1989 to 1997 have been analyzed. An evaluation of malaria incidence in Italian travelers has been also performed for the same period, based on the statistics provided by the Ministry of Transport. Results: From 1989 to 1997, a total of 5,898 microscopically confirmed malaria cases have been reported. Of these, 5,773 (97.9%) were imported cases, 106 cases (1.8%) were relapses of Plasmodium vivax or Plasmodium ovale infections, and 19 cases (0.3%) occurred in subjects who had never been out of Italy. During the period of study, 55 deaths due to Plasmodium falciparum malaria were reported, with a mean fatality rate of 1.2%. Malaria incidence in Italians who traveled to Africa was estimated to be 1.5/1000. These figures appeared to be 10,20 and 30,40 times greater than that recorded in travelers to Asia (0.11/1000) and Central-South America (0.04/1000) respectively. Conclusions: From 1989 to 1997, there has been a remarkable increase in the total number of imported malaria cases in Italy, which reached a peak of more than 800 cases/year in 1997. A constant increase in the number of cases affecting foreigners has been reported, while the cases among Italians have remained stable. From 1989 to 1997 the number of Italian intercontinental travelers has nearly doubled, but malaria incidence has remained quite stable. [source] Evaluation of a family-oriented continuing medical education course for general practitionersMEDICAL EDUCATION, Issue 3 2002Anja Taanila Objective To explore the long-term effects of a 2-year Family Systems Medicine course. Fifteen experienced GPs participated in the training programme. Setting Continuing Education Centre, University of Tampere, Department of Public Health Science and General Practice, University of Oulu, Finland. Methods The participants assessed the development of their professional skills on the Doherty-Baird scale and filled in 2 questionnaires. The material obtained from the application form and 2 questionnaires was analysed using the grounded theory method. Results The reasons for taking part in the course seemed to be the constant increase in the workload, problems caused by the demands for change and adaptation, stress and exhaustion. Furthermore, 10 health centres out of 15 had adopted the population-based practice, which requires different working methods compared to the old routines. Some trainees reported that their family-centred working methods improved during the course. A year after the end of the training, all of the GPs who had participated were using such methods in their daily practice. Half of the participants felt that they had also improved the functioning of their working group by making it more family-oriented. The significance of multiprofessional collaboration was one of the most important insights during the course. Conclusion The 2-year family-oriented training programme provided GPs with systemic thinking and with new skills, including the ability to work with families. The programme raised awareness of the need for multiprofessional collaboration in the primary care sittings. [source] Changes in the impact factor of anesthesia/critical care journals within the past 10 yearsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 7 2000J. Boldt Background: The impact factor (IF) is published by the Institute for Scientific Information (ISI). There is a tendency to assess quality of scientific journals with the help of the IF. An analysis of the changes in the IF over time in the different specialities may help to further enlighten the worth and problems of the IF. Methods: The IFs listed under the subheadings Anesthesiology and Emergency Medicine & Critical Care in the Science Citation Index , Journal Citation Report were descriptively analysed over the past 10 years. Additionally, IFs of some other important journals (subheadings Surgery, Cardiovascular, General Medicine) were analysed. Results: The IF of most of the journals showed a constant increase over the years (average in Anesthesiology: +65%; average in Emergency Medicine & Critical Care: +145%). IFs of the highest ranked journals of other specialities showed a similar increase over the years (average in surgical journals: +56%; average in cardiac journals: +59%; average in general journals: +40%). More Anesthesiology and Emergency Medicine & Critical Care journals originated from the USA show an IF >2.0 over the past 10 years than do European journals. Conclusion: Although the value of the IF is highly controversial, it is a frequently used tool to assess rating of a medical journal. Anesthesiology and Emergency Medicine & Critical Care journals showed a continuous increase in the IF over the past 10 years. [source] Colpo-wrap: a new continence procedureBJU INTERNATIONAL, Issue 7 2005Thomas M. Boemers OBJECTIVE To present a new surgical method to increase bladder outlet resistance for the treatment of urinary incontinence in girls and women. PATIENTS AND METHODS Six patients (mean age 9.6 years), with urinary incontinence were operated using the new technique within the last 3 years. The principle of the procedure is tightening of the bladder neck by mobilizing the anterior vaginal wall and wrapping it around the bladder neck and proximal urethra, in the sense of a vaginoplication (colpoplication). The underlying conditions and causes for urinary incontinence was neurogenic bladder-sphincter dysfunction caused by myelodysplasia in three girls and anorectal malformation combined with a tethered spinal cord in one. In one case incontinence was caused by a cloacal anomaly and one girl had intrinsic sphincter insufficiency after repetitive Otis urethrotomies. The colpo- wrap was combined with a bladder augmentation and Mitrofanoff in three patients, the three other girls undergoing isolated procedures. RESULTS The result of the method is a constant increase in outlet resistance and coaptation of the urethra, comparable with the effect of a vaginal sling procedure. Five patients are completely dry after surgery, one girl with cloaca needed an additional bladder neck injection with hyaluranon/dextranomer copolymer. Transurethral catheterization was possible after surgery with no problems in all patients who required intermittent catheterization. CONCLUSION Considering the feasibility of this technique the colpo-wrap is a reasonable alternative for treating urinary incontinence in females. [source] Enlargement of calcium oxalate stones to clinically significant size in an in-vitro stone generatorBJU INTERNATIONAL, Issue 9 2002K. Ananth Objective ,To develop and validate an in vitro method suitable for the quantitative investigation of the growth of calcium oxalate stones through to a clinically significant size. Materials and methods ,Small fragments of calcium oxalate calculi were suspended in a mixed suspension/mixed product removal crystalliser supplied with artificial urine supersaturated with calcium oxalate. The fragments were weighed at regular intervals until they reached ,,500 mg. The results were plotted as weight against time and fitted to equations corresponding to constant increase in diameter, surface area-controlled and constant-deposition growth patterns. The choice of the most appropriate model was based on the squared regression coefficient (r2). Results ,Eight fragments (2,6 mm in diameter) were grown to ,,10 mm in diameter over periods from 137 to 369 h. Seven of the growth curves were best-fitted (r2 , 0.988) by the equation w = kt(3/2) + c, where w is the weight, k is a growth constant, t is the time and c is a constant approximating to the initial weight. This corresponds to a surface area-dependent mechanism. Conclusions ,The growth of these small fragments to a clinically significant size accelerated throughout the experimental period in a way which was consistent with a surface area-dependent mechanism. We have developed a resilient model suitable for studying the kinetics of calcium oxalate stone growth in vitro. [source] Body mass index references for Turkish childrenACTA PAEDIATRICA, Issue 2 2006Ruveyde Bundak Abstract Aim: To construct the body mass index reference curves for Turkish children aged 6 to 18 y, and to determine the prevalence of overweight and obesity. Subjects and methods: Height and weight measurements of healthy schoolchildren (1100 boys, 1019 girls) were obtained biannually. Body mass index was calculated from 11,648 height and weight measurements. Centile curves were constructed using the LMS method. Results: The smoothed percentile values and curves for body mass index in Turkish children show that there is a constant increase in body mass index values towards adulthood, especially during the pubertal years, in both sexes. The prevalence of overweight is 25% and obesity 4% in boys at age 18 y. The percentage of overweight and obesity in girls at age 14 was 15% and 1%, respectively. The sample size was too small to come to any conclusion regarding these rates at 18 y of age. Conclusion: This study presents data and curves for body mass index values in healthy Turkish children aged 6 to 18 y. The values are in compliance with those of Western countries. [source] The Effect of Surface Area and Crystal Structure on the Catalytic Efficiency of Iron(III) Oxide Nanoparticles in Hydrogen Peroxide DecompositionEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 16 2010Cenek Gregor Abstract Iron(II) oxalate dihydrate has been used as a readily decomposable substance for the controlled synthesis of nanosized iron(III) oxides. The polymorphous composition, particle size and surface area of these iron oxide nanoparticles were controlled by varying the reaction temperature between 185 and 500 °C. As-prepared samples were characterized by XRD, low-temperature and in-field Mössbauer spectroscopy, BET surface area and the TEM technique. They were also tested as heterogeneous catalysts in hydrogen peroxide decomposition. At the selected temperatures, the formed nanomaterials did not contain any traces of amorphous phase, which is known to considerably reduce the catalytic efficiency of iron(III) oxide catalysts. As the thickness of the sample (, 2 mm) was above the critical value, a temporary temperature increase ("exo effect") was observed during all quasi-isothermal decompositions studied, irrespective of the reaction temperature. Increasing the reaction temperature resulted in a shift of the exo effect towards shorter times and an increased content of maghemite phase. The maghemite content decreases above 350 °C as a result of a thermally induced polymorphous transition into hematite. The catalytic data demonstrate that the crystal structure of iron(III) oxide (i.e. the relative contents of maghemite and hematite) does not influence the rate of hydrogen peroxide decomposition. However, the rate constant increases monotonously with increasing sample surface area (and decreasing thermolysis temperature), reaching a maximum of 27,×,10,3 min,1(g/L),1 for the sample with a surface area of 285 m2,g,1. This rate constant is currently the highest reported value of all known iron oxide catalytic systems and is even slightly higher than that observed for the most efficient catalyst reported to date, which has a significantly larger surface area of 337 m2,g,1. This surprisingly high catalytic activity at relatively low surface area can be ascribed to the absence of a amorphous phase in the samples prepared in this study. Taking into account these new findings, the contributions of the key factors highlighted above (surface area, particle size, crystal structure, crystallinity) to the overall activity of iron oxides forhydrogen peroxide decomposition are discussed. [source] The effects of physiologically important nonmetallic ligands in the reactivity of metallothionein towards 5,5,-dithiobis(2-nitrobenzoic acid)FEBS JOURNAL, Issue 18 2001A new method for the determination of ligand interactions with metallothionein The reaction of Cd5Zn2 -metallothionein (MT) with 5,5,-dithiobis(2-nitrobenzoic acid) (Nbs2) has been studied at different reagent stoichiometries, pH and temperature conditions and in the presence of several ligands. At stoichiometries of Nbs2 to MT from 0.5 to 5, the reaction followed first order kinetics. The first order rate constants obtained were independent from the concentration of Nbs2 but were linearly dependent on the concentration of MT. At higher Nbs2/MT stoichiometries, the reaction deviates from first order kinetics and the observed rate constant increases. The reactivity of MT towards Nbs2 has been probed at 4 µm concentration of both reagents where the reaction is monophasic and is characterized by a linear Arrhenius plot (Ea = 45.8 ± 2.7 kJ·mol,1). It has been demonstrated that metal release at low pH or subtraction from MT by EDTA substantially increases the reactivity of MT towards Nbs2. At the same time, a number of nonmetallic ligands moderately accelerate the reaction of MT with Nbs2 and hyperbolic dose,response curves were obtained. The data have been interpreted with the binding of ligands to MT and following MT. Ligand binding constants were calculated as follows: ATP, K = 0.31 ± 0.06 mm; ADP, K = 0.26 ± 0.07 mm. Several compounds such as AMP, S -methylglutathione, and phosphate had no effect on the reaction, but Zn2+ ions showed an inhibitory effect at micromolar concentrations. [source] Solvent effects on kinetics of an aromatic nucleophilic substitution reaction in mixtures of an ionic liquid with molecular solvents and prediction using artificial neural networksINTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 3 2009Aziz Habibi-Yangjeh Kinetics of the reaction between 1-chloro-2,4-dinitrobenzene and aniline was studied in mixtures of 1-ethyl-3-methylimidazolium ethylsulfate ([EMIM][EtSO4]) with methanol, chloroform, and dimethylsulfoxide at 25°C. Single-parameter correlations of log kA versus normalized polarity parameter (ENT), hydrogen-bond acceptor basicity (,), hydrogen-bond donor acidity (,), and dipolarity/polarizability (,*) of media do not give acceptable results. Multiparameter linear regression (MLR) of log kA versus the solvatochromic parameters demonstrates that the reaction rate constant increases with ENT, ,*, and , and decreases with , parameter. To predict accurately solvent effects on the rate constant, optimized artificial neural network with three inputs (including ,, ,*, and , parameters) was applied for prediction of the log kA values in the prediction set. It was found that properly selected and trained neural network could fairly represent the dependence of the reaction rate constant on solvatochromic parameters. Mean percent deviation of 5.023 for the prediction set by the MLR model should be compared with the value of 0.343 by the artificial neural network model. These improvements are due to the fact that the reaction rate constant shows nonlinear correlations with the solvatochromic parameters. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 41: 153,159, 2009 [source] Hydrogen response in liquid propylene polymerization: Towards a generalized modelAICHE JOURNAL, Issue 5 2006M. Al-haj Ali Abstract Liquid propylene batch experiments in the absence of a gas phase have been carried out using a highly-active MgCl2/TiCl4/phthalate/silane/AlR3 catalyst at varying temperatures (60-80°C) and molar hydrogen-monomer ratios of 0-10 mmol/mol. With increasing hydrogen concentration the polymerization rate increases rapidly, reaching a constant value at concentrations above 1.4 mmol/mol; pseudo-first-order catalyst deactivation constant increases; molecular weight decreases; polydispersity decreases slightly; but average molecular weight and polydispersity increase with increasing temperature. Polymerization rate, deactivation constant, and average molecular weight can be modeled based on a consistent dormant site mechanism assuming an (averaged) quasi-single-site model. © 2006 American Institute of Chemical Engineers AIChE J,2006 [source] Non-aqueous reverse micelles media for the SNAr reaction between 1-fluoro-2,4-dinitrobenzene and piperidine,JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 12 2006N. Mariano Correa Abstract The kinetics of the nucleophilic aromatic substitution (SNAr) reaction between 1-fluoro-2,4- dinitrobenzene (FDNB) and piperidine (PIP) in ethylene glycol (EG)/ sodium bis (2-ethyl-1-hexyl) sulfosuccinate (AOT)/n -heptane and dimethylformamide (DMF)/AOT/n -heptane non-aqueous reverse micelle systems is reported. EG and DMF were used as models for hydrogen bond donor (HBD) and non-hydrogen bond donor (non-HBD) polar solvents, respectively. The reaction was found not to be base catalyzed in these media. A mechanism to rationalize the kinetic results is proposed in which both reactants may be distributed between the two environments. The distribution constants of FDNB between the organic and each micellar pseudophases were determined by an independent fluorescence method. These results were used to evaluate the amine distribution constant and the intrinsic second-order rate coefficient of the SNAr reaction in the interface. The reaction was also studied in the pure solvents EG and DMF for comparison. The results in EG/AOT/n -heptane at Ws,=,2 give similar kinetic profiles than in water/AOT/n -hexane at W,=,10. With these HBD solvents, the interface saturation by the substrate is reached at around the same value of [AOT] and the intrinsic second-order rate coefficient in the interface, k,b, has comparable values. On the other hand, when DMF is used as a polar non-HBD solvent, the intrinsic second-order rate constant increases by a factor of about 200 as compared to the values obtained using HBD solvents as a polar core. It is concluded that higher catalytic power is obtained when non-HBD solvents are used as polar solvent in the micelle interior. Copyright © 2006 John Wiley & Sons, Ltd. [source] Dielectric Properties of Electrophoretically Deposited and Isothermally Pressed BaTiO3 Thick FilmsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 6 2008Ling Zhang Thick BaTiO3 films were prepared on platinum metallic foils by the electrophoretic deposition (EPD) technique using BaTiO3 nanoparticles. In order to increase the density of the thick film, the green film was pressed under an isostatic pressure of 200 MPa before high-temperature sintering. The microstructures of deposited films were examined using X-ray diffraction and scanning electron microscopy techniques. Dielectric properties of the thick films were investigated. As the films grow thicker, the dielectric constant increases gradually and the dielectric loss decreases slightly. The experimental results indicate that isostatic pressing is an effective method to process thick films with dense microstructure and better dielectric properties. [source] Ferroelectric and Piezoelectric Properties of Na1,xBaxNb1,xTixO3 CeramicsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 9 2006J. T. Zeng Piezoelectric ceramics Na1,xBaxNb1,xTixO3 with low BaTiO3 concentrations x have been prepared by the solid-state reaction method, and their ferroelectric and piezoelectric properties have been studied. The ceramics are classic ferroelectrics when x,0.10, and the ferroelectric,paraelectric phase transition becomes diffusive when x,0.15. A low doping level of BaTiO3 changes the NaNbO3 ceramics from antiferroelectric to ferroelectric. With the increase in BaTiO3 doping level, the Curie temperature of ceramics decreases linearly and the remnant polarization and coercive field also decrease, while their dielectric constant increases. Na0.9Ba0.1Nb0.9Ti0.1O3 ceramics show the largest piezoelectric constant d33 (147 pC/N) and good sinterability, suggesting that it is a good candidate for lead-free piezoelectric ceramics. [source] Maxwell Fluid Model for Generation of Stress,Strain Curves of Viscoelastic Solid Rocket PropellantsPROPELLANTS, EXPLOSIVES, PYROTECHNICS, Issue 4 2010Himanshu Shekhar Abstract Solid rocket propellants are modeled as Maxwell Fluid with single spring and single dashpot in series. Complete stress,strain curve is generated for case-bonded composite propellant formulations by taking suitable values of spring constant and damping coefficient. Propellants from same lot are tested at different strain rate. It is observed that change in spring constant, representing elastic part is very small with strain rate but damping constant varies significantly with variation in strain rate. For a typical propellant formulation, when strain rate is varied from 0.00037 to 0.185 per second, spring constant (K) changed from 5.5 to 7.9,MPa, but damping coefficient (D) varied from 1400 to 4,MPas. For all strain rates, stress,strain curve is generated using developed Maxwell model and close matching with actual test curve is observed. This indicates validity of Maxwell fluid model for case-bonded solid propellant formulations. It is observed that with increases in strain rate, spring constant increases but damping coefficient decreases representing solid rocket propellant as a true viscoelastic material. It is also established that at higher strain rate, damping coefficient becomes negligible as compared to spring constant. It is also observed that variation of spring constant is logarithmic with strain rate and that of damping coefficient follows a power law. The correlation coefficients are introduced to ascertain spring constants and damping coefficients at any strain rate from that at a reference strain rate. Correlation for spring constant needs a coefficient "H," which is function of propellant formulation alone and not of test conditions and the equation developed is K2=(K1 - H)×{ln(d,2/dt)/ln(d,1/dt)}+H. Similarly for damping coefficient (D) also another constant "S" is introduced and prediction formula is given by D2=D1×{(d,2/dt)/(d,1/dt)}S. Evaluating constants "H" and "S" at different strain rates validate this mathematical formulation for different propellant formulations. Close matching of test and predicted stress,strain curve indicates propellant behavior as viscoelastic Maxwell Fluid. Uniqueness of approach is to predict complete stress,strain curves, which are not attempted by any other researchers. [source] Kinetic and DFT Studies on the Photoinduced Desorption of Sulfur from Gold Nanoparticles Loaded on Titanium DioxideCHEMPHYSCHEM, Issue 12 2005Tomokazu Kiyonaga Cleaning poisoned gold catalysts: Kinetic analysis of the photoinduced desorption of sulfur from gold nanoparticles loaded on TiO2 particles in water revealed that the rate constant increases with increasing pH. Photoelectrochemical measurements and DFT calculations led to the conclusion that this reaction results from an upward shift in the Fermi energy of gold nanoparticles by irradiation. The picture shows a high-resolution TEM image of an Au nanoparticle on TiO2. [source] | |||||||||||||