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Ceolin René - - 2010
The pressure-temperature (P-T) melting curve of lidocaine was determined (dP/dT = 3.56 MPa K(-1)), and the lidocaine-water system was investigated as a function of temperature and pressure. The lidocaine-water system exhibits a monotectic equilibrium at 321 K (ordinary pressure) whose temperature increases as the pressure increases until the two liquids ...
Kawasaki S - - 2010
This paper reports the structural properties of the high-pressure and high-temperature (HPHT) treated double-walled carbon nanotubes (DWCNTs) based on Raman, XRD and TEM experiments. It was found that the DWCNTs are more stable toward HPHT treatment than the single-walled carbon nanotubes (SWCNTs). We propose that this is probably because the ...
Brooks Nicholas J - - 2010
A high pressure cell for small and wide-angle x-ray diffraction measurements of soft condensed matter samples has been developed, incorporating a fully automated pressure generating network. The system allows both static and pressure jump measurements in the range of 0.1-500 MPa. Pressure jumps can be performed as quickly as 5 ...
Mierzwa Michal - - 2010
We present a new technique to prepare insulated channels for the high pressure cell used in broadband dielectric spectroscopy. The cell resists corrosion or other chemical reactions from the reactive sample liquids. The cell maintains electrical insulation between electrode contacts better than 100 GOmega as well as good mechanical properties ...
Chen B - - 2010
The new peak (near 1850 cm(-1)) assigned to carbon linear chain included in the centre of very thin innermost multiwalled carbon nanotubes (MWNTs) has been verified by Raman spectroscopy. These MWNTs were produced by dc arc discharge of pure graphite rods in pure hydrogen gas and existed in the cathode ...
Gilles Sandra - - 2010
Soft nanoimprint lithography (soft NIL) relies on a mechanical deformation of a resist by a patterned polymer used as a mold. Here, we report on the investigation of the nanopattern fidelity of the high pressure imprint process based on a perfluorinated polyether (PFPE) soft mold material. The perfluorinated polyether material ...
Wlodarczyk P - - 2010
Dielectric spectroscopy has been recently used to monitor mutarotation in undercooled D-fructose. This method can be viewed as a universal method to study mutarotation phenomenon in the whole family of monosaccharides. In this paper, we studied kinetics of mutaration of anhydrous D-ribose at ambient pressure as well as pressure effect ...
Adrjanowicz K - - 2010
Dielectric spectroscopy (DS) was used to investigate the relaxation dynamics of supercooled and glassy ibuprofen at various isobaric and isothermal conditions (pressure up to 1750 MPa). The ambient pressure data are in good agreement with that reported previously in the literature. Our high pressure measurements revealed validity of temperature-pressure superpositioning ...
Bonetti Marco - - 2010
We investigate by fluorescence microscopy the bulk fluorescence photobleaching of coumarin 1 and fluorescein in different solvents as a function of pressure up to 3.5 kbar. We show that for coumarin 1, the decrease in the fluorescence intensity is well described by a single exponential function whose characteristic time decreases ...
Mehravaran Hossein - - 2010
Measurements of molecular and atomic fluorine laser emissions were done from 2?psi (absolute) to 5?atm to determine pressure-dependent spectral lines. While at low pressures, the atomic transitions are dominant; however, both atomic and molecular transitions are detected simultaneously at atmospheric pressures above approximately 2?atm, where a changeover occurs. The excitation ...
Girard Eric - - 2010
Structure-function relationships in the tetrameric enzyme urate oxidase were investigated using pressure perturbation. As the active sites are located at the interfaces between monomers, enzyme activity is directly related to the integrity of the tetramer. The effect of hydrostatic pressure on the enzyme was investigated by x-ray crystallography, small-angle x-ray ...
Gong Weijin - - 2010
Oxidation of landfill leachate wastewater was studied in a transpiring-wall SCWO reactor, operated under varied temperature and pressure 320-430 °C, 18-30 MPa. Effect of temperature and pressure on COD and BOD removal efficiency was investigated. COD and BOD removal efficiency being 99.23%, 98.06% were achieved at 430 °C, 30 MPa, ...
Jin Xilian - - 2010
High-pressure structures of disilane (Si(2)H(6)) are investigated extensively by means of first-principles density functional theory and a random structure-searching method. Three metallic structures with P-1, Pm-3m, and C2/c symmetries are found, which are more stable than those of XY(3)-type candidates under high pressure. Enthalpy calculations suggest a remarkably wide decomposition ...
Yusa Hitoshi - - 2010
In situ X-ray diffraction experiments and ab initio calculations elucidated the high-pressure phase transition properties of yttrium sesquioxides. The C-, B-, and A-type sesquioxides structure sequence observed in the room-temperature compression does not coincide with the high-pressure phase sequence of yttrium sesquioxides at high temperature. A reconstructive-type transformation taking place ...
Winship Lawrence J - - 2010
Significant controversy still swirls around the regulation of extension by tip-growing cells, particularly during stable, oscillatory growth of pollen tubes. One explanation proposes that turgor pressure is both the controlling and driving force. We refute this hypothesis on theoretical and evidentiary grounds. Direct measurement of intracellular pressure reveals constant turgor ...
Mao Wendy L - - 2010
Ca-III, the first superconducting calcium phase under pressure, was identified as simple-cubic (sc) by previous X-ray diffraction (XRD) experiments. In contrast, all previous theoretical calculations showed that sc had a higher enthalpy than many proposed structures and had an imaginary (unstable) phonon branch. By using our newly developed submicrometer high-pressure ...
Friedrich Alexandra - - 2010
The crystal structure of the high-pressure phase of bismuth gallium oxide, Bi(2)Ga(4)O(9), was determined up to 30.5 (5) GPa from in situ single-crystal in-house and synchrotron X-ray diffraction. Structures were refined at ambient conditions and at pressures of 3.3 (2), 6.2 (3), 8.9 (1) and 14.9 (3) GPa for the ...
Sarupria Sapna - - 2010
Many globular proteins unfold when subjected to several kilobars of hydrostatic pressure. This "unfolding-up-on-squeezing" is counter-intuitive in that one expects mechanical compression of proteins with increasing pressure. Molecular simulations have the potential to provide fundamental understanding of pressure effects on proteins. However, the slow kinetics of unfolding, especially at high ...
Maier Bernd J - - 2010
We have employed a combination of powder neutron diffraction and single-crystal synchrotron X-ray diffraction to characterize the pressure-induced phase transitions that occur in the perovskite-type relaxor ferroelectric PbSc(0.5)Ta(0.5)O(3) (PST) and Pb(0.78)Ba(0.22)Sc(0.5)Ta(0.5)O(3) (PST-Ba). At ambient pressure the symmetry of the average structure for both compounds is Fm3m as a result of ...
McArdle R - - 2010
The combined effects of high pressure processing (HPP) and temperature on meat quality attributes were assessed in bovine M. pectoralis profundus, with particular focus on lipid oxidation and fatty acid composition. Beef samples were pressurised at 200, 300 and 400 MPa at two different temperatures 20°C and 40°C. Both pressure ...
Karki Bijaya B - - 2010
Understanding the chemical and thermal evolution of Earth requires knowledge of transport properties of silicate melts at high pressure and high temperature. Here, first-principles molecular dynamics simulations show that the viscosity of MgSiO3 liquid varies by two orders of magnitude over the mantle pressure regime. Addition of water systematically lowers ...
Emmons Erik D - - 2010
High-pressure Raman spectroscopy has been used to study tris(hydroxymethyl)aminomethane (C(CH(2)OH)(3)NH(2), Tris). Molecules with globular shapes such as Tris have been studied thoroughly as a function of temperature and are of fundamental interest because of the presence of thermal transitions from orientational order to disorder. In contrast, relatively little is known ...
Schindler Sabrina - - 2010
Chicken breast and beef muscle were treated at 400 and 600 MPa for 15 min at 5 degrees C and compared to raw meat and a heated sample (100 degrees C for 15 min). Vacuum-packed beef meat with a smaller fraction of unsaturated fatty acids showed better oxidative stability during ...
Chung Hyun-Jung - - 2010
The purpose of this study was to evaluate combinations of high pressure processing (HPP) and Lactobacillus casei antimicrobial activity against Listeria monocytogenes strains with variation in pressure resistance in culture and in a food model. In culture, combination of HPP (350 MPa, for 1-20 min) and Lb. casei cell extract ...
Eisenmenger Michael J - - 2010
Lipase-catalyzed synthesis of isoamyl acetate in hexane at 10-250 MPa at 80 degrees C and 1-100 MPa at 40 degrees C resulted in activation volumes of -12.9 +/- 1.7 and -21.6 +/- 2.9 cm(3) mol(-1), respectively. Increasing pressure from 10 to 200 MPa resulted in approximately 10-fold increase in V(max) ...
Jewart Charles M - - 2010
We present fiber Bragg grating pressure sensors in air-hole microstructured fibers for high-temperature operation above 800 degrees C. An ultrafast laser was used to inscribe Type II grating in two-hole optical fibers. The fiber Bragg grating resonance wavelength shift and peak splits were studied as a function of external hydrostatic ...
Vass Hugh - - 2010
We have developed a modular system for high-resolution microscopy at high hydrostatic pressure. The system consists of a pressurized cell of volume approximately 100 microl, a temperature controlled holder, a ram, and a piston. We have made each of these components in several versions which can be interchanged to allow ...
Velazquez Gonzalo - - 2010
The Mexican fruit fly Anastrepha ludens Loew (Diptera: Tephritidae) is one of the most important insects infesting mangoes, citrus, and other fruits in Mexico and other Latin-American countries. Quarantine methods approved to destroy this insect decrease the shelf life of commodities. The objective of this study was to determine the ...
Berheide Marco - - 2010
Benzoylformate decarboxylase (BFD) from Pseudomonas putida is a thiamine diphosphate-dependent (ThDP) enzyme that catalyzes the asymmetric C--C bond formation to (S)-2-hydroxypropiophenone [(S)-HPP] starting from benzaldehyde and acetaldehyde. The enantioselectivity of BFD was shown to be a function of temperature and substrate concentration. It can additionally be changed by site-directed mutagenesis ...
Zimmermann U - - 2010
Turgor pressure provides a sensitive indicator for irrigation scheduling. Leaf turgor pressure of Musa acuminate was measured by using the so-called leaf patch clamp pressure probe, i.e. by application of an external, magnetically generated and constantly retained clamp pressure to a leaf patch and determination of the attenuated output pressure ...
Vevers William F - - 2010
The effect of high hydrostatic pressures on the ecotoxicological profile of pollutants is an unexplored research area. Using Pomatoceros lamarcki as a surrogate organism for this eco-barotoxicological study, it was found that in a 48 h larval bioassay with water accommodated fractions (WAF) of crude oil of up to 15.1 ...
Friedrich Frank - - 2010
Over the last decades infrared spectroscopy has become a frequently used method to investigate the structure and bonding properties of clay minerals. Along with classic transmission techniques, attenuated total reflection (ATR) spectroscopy has been applied as a very fast and easy method. In this study we compared transmission spectra of ...
Kim S A - - 2010
The objective of this study was to develop a viable new method for inactivation of Cronobacter spp. that could be applied directly to dehydrated powdered infant formula (PIF) using supercritical carbon dioxide (SC-CO(2)). Samples inoculated with Cronobacter spp. were subjected to SC-CO(2) treatment under various conditions (temperature: 63, 68, and ...
Yoon Sung-Ran - - 2010
The puffing process was evaluated as an alternative to the steaming process for producing a biologically more active ginseng product, like red ginseng, from raw ginseng. A puffing treatment of dried raw ginseng roots induced an overall increase in crude saponin content. As puffing pressure increased, the content of ginsenoside ...
Xie Yu - - 2010
Using evolutionary methodology for crystal structure prediction, we explore high-pressure phases of CaLi2, a compound made of two elements that show anomalies upon compression. In addition to the known low-pressure Laves phases, we find two novel structures with space groups C2/c and P2{1}/c, stable at pressure ranges of 35-54 GPa ...
Kamerlin Shina Caroline Lynn - - 2010
The idea that tunneling is enhanced by the compression of the donor-acceptor distance has attracted significant interest. In particular, recent studies argued that this proposal is consistent with pressure effects on enzymatic reactions, and that the observed pressure effects support the idea of vibrationally enhanced catalysis. However, a careful analysis ...
Sumi Tomonari - - 2010
A thermodynamic analysis of high-temperature and low-pressure unfolding of proteins using a coarse-grained multiscale simulation combined with a liquid-state density-functional theory is presented. In this study, a hydrophobic polymer chain is employed as a probe molecule for investigating qualitative changes in a hydration free energy surface acting on proteins with ...
Larios Edgar - - 2010
We record proton NMR spectra of the protein ubiquitin at 1 atmosphere pressure and at negative pressures (under tension), under conditions where the native and denatured states are nearly equally populated. Analysis of the unique histidine aromatic resonance of ubiquitin shows that negative pressure destabilizes the protein, in accord with ...
Xu Zhenzhen - - 2010
The extraction kinetics of anthocyanins from red cabbage using high pressure CO(2) (HPCD) against conventional acidified water (CAW) was investigated. The HPCD time, temperature, pressure and volume ratio of solid-liquid mixture vs. pressurized CO(2) (R((S+L)/G)) exhibited important roles on the extraction kinetics of anthocyanins. The extraction kinetics showed two phases, ...
Su Lei - - 2010
To develop a new practical method of purifying and recycling ionic liquids, we performed direct microscopic observations and in situ crystallization of low-melting ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF(6)]), in detail by high pressure Raman spectroscopy. Compression of [BMIM][PF(6)] was measured under pressures up to about 2.0 GPa at temperatures 293-353 ...
Grigera J Raúl - - 2010
It is well known that proteins denature under high pressure. The mechanism that underlies such a process is still not clearly understood, however, giving way to controversial interpretations. Using molecular dynamics simulation on systems that may be regarded experimentally as limiting examples of the effect of high pressure on globular ...
Cobos C J - - 2010
Limiting low- and high-pressure rate coefficients as well as full falloff curves have been modeled by unimolecular rate theory for the recombination reaction 2CF(3) (+ M) --> C(2)F(6) (+ M) and the reverse dissociation of C(2)F(6). The results are compared with experimental data from the literature. Although there are considerable ...
Rivalain Nolwennig - - 2010
Compared to temperature, the development of pressure as a tool in the research field has emerged only recently (at the end of the XIXth century). Following several developments in Physics and Chemistry during the first half of the XXth century (in particular the synthesis of diamond in 1953-1954), high pressures ...
Fragiadakis D - - 2010
The dielectric spectra of most simple liquids are characterized by two relaxation processes: (i) the alpha-process, an intense, broad non-Debye relaxation with a non-Arrhenius temperature dependence and (ii) a beta process, evident mainly below the glass transition and having nearly Arrhenius temperature behavior. However, the dielectric spectra of monoalcohols show ...
Iseki Sachiko - - 2010
A promising, environmentally safe method for inactivating fungal spores of Penicillium digitatum, a difficult-to-inactivate food spoilage microorganism, was developed using a high-density nonequilibrium atmospheric pressure plasma (NEAPP). The NEAPP employing Ar gas had a high electron density on the order of 10(15) cm(-3). The spores were successfully and rapidly inactivated ...
Oganov Artem R - - 2010
Experimental studies established that calcium undergoes several counterintuitive transitions under pressure: fcc --> bcc --> simple cubic --> Ca-IV --> Ca-V, and becomes a good superconductor in the simple cubic and higher-pressure phases. Here, using ab initio evolutionary simulations, we explore the behavior of Ca under pressure and find a ...
Morandi Brunella - - 2010
The kiwifruit berry is characterized by an early stage of rapid growth, followed by a relatively long stage of slow increase in size. Vascular and transpiration flows are the main processes through which water and carbon enter/exit the fruit, determining the daily and seasonal changes in fruit size. This work ...
Paudel K - - 2010
Polyfluorenes (PFs) represent a unique class of poly-para-phenylene-based blue-emitting polymers with intriguing structure-property relationships. Slight variations in the choice of functionalizing side chains result in dramatic differences in the inter- and intrachain structures in PFs. Dioctyl-substituted PF (PF8) is characterized by different backbone conformations that depend upon the torsion angle ...
Roche Yann - - 2010
We monitored the behavior of plasma membrane (PM) isolated from tobacco cells (BY-2) under hydrostatic pressures up to 3.5kbar at 30 degrees C, by steady-state fluorescence spectroscopy using the newly introduced environment-sensitive probe F2N12S and also Laurdan and di-4-ANEPPDHQ. The consequences of sterol depletion by methyl-beta-cyclodextrin were also studied. We ...
Grossi Vincent - - 2010
A new piezotolerant alkane-degrading bacterium (Marinobacter hydrocarbonoclasticus strain #5) was isolated from deep (3475 m) Mediterranean seawater and grown at atmospheric pressure (0.1 MPa) and at 35 MPa with hexadecane as sole source of carbon and energy. Modification of the hydrostatic pressure influenced neither the growth rate nor the amount ...
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