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101.
The solubility and diffusion of carbon dioxide into cooked meat products (cooked ham and meat sausage with different pH-levels) was determined at different starting pressures and gas to product volume ratios by monitoring pressure changes over time in a closed chamber at constant temperatures (0, 4, and 8 °C). Good correlation of the CO2 solubility between the packaging parameters (gas to product volume ratio and initial partial pressure) and the meat products water content was found. The solubility of CO2 followed Henry’s law and the initial partial pressure of CO2 influenced the solubility mostly. Only small variations in the diffusion constants and absorption rates were found within the experimental design. A pH difference of 0.5 in the two meat sausage types did not influence either solubility or diffusion significantly. 相似文献
102.
In this paper we describe the rational design, synthesis and pharmacological evaluation of two new stereoisomeric (S)‐glutamate (Glu) analogues. The rational design was based on hybrid structures of the natural product kainic acid, a synthetic analogue CPAA and the high‐affinity Glu analogue SYM2081. Pharmacological evaluation of the two stereoisomers revealed that one stereoisomer showed a subtype selectivity profile with low micromolar affinity for GluK1 and GluK3 and a 10‐ to 15‐fold lower affinity for GluK2. The other stereoisomer displayed full selectivity for the KA over AMPA and NMDA receptors (GluK1–3: 0.39, 0.51 and 0.099 µM , respectively). 相似文献
103.
Dmytro Korablov Jonas Ångström Morten B. Ley Martin Sahlberg Flemming Besenbacher Torben R. Jensen 《International Journal of Hydrogen Energy》2014
Scandium(II)hydride, ScH2, and scandium(III)chloride, ScCl3, are explored as additives to facilitate hydrogen release and uptake for magnesium hydride. These additives are expected to form more homogeneous composites with Mg/MgH2 as compared to metallic scandium. However, scandium(III)chloride, reacts with MgH2 during mechano-chemical treatment and form ScH2 and MgCl2 (that later crystallise during heat treatment). The composite MgH2−ScH2 was investigated using in-situ synchrotron radiation powder X-ray diffraction during up to five cycles of continuous release and uptake of hydrogen at isothermal conditions at 320, 400 and 450 °C and p(H2) = 100–150 or 10−2 bar. The data were analysed by Rietveld refinement and no reaction is observed between either MgH2/ScH2 or Mg/ScH2 during cycling. The extracted sigmoidal shaped curves for formation or decomposition of Mg/MgH2 suggest that a nucleation process is preceding the crystal growth. The reaction rate increases with increasing number of cycles of hydrogen release and uptake at isothermal conditions possibly due to activation effects. This kinetic enhancement is strongest between the first cycles and may be denoted an activation effect. 相似文献
104.
Meimei Li M. Eldrup T.S. Byun N. Hashimoto L.L. Snead S.J. Zinkle 《Journal of Nuclear Materials》2008,376(1):11-28
Polycrystalline molybdenum was irradiated in the hydraulic tube facility at the High Flux Isotope Reactor to doses ranging from 7.2 × 10−5 to 0.28 dpa at 80 °C. As-irradiated microstructure was characterized by room-temperature electrical resistivity measurements, transmission electron microscopy (TEM) and positron annihilation spectroscopy (PAS). Tensile tests were carried out between −50 and 100 °C over the strain rate range 1 × 10−5 to 1 × 10−2 s−1. Fractography was performed by scanning electron microscopy (SEM), and the deformation microstructure was examined by TEM after tensile testing. Irradiation-induced defects became visible by TEM at 0.001 dpa. Both their density and mean size increased with increasing dose. Submicroscopic three-dimensional cavities were detected by PAS even at 0.0001 dpa. The cavity density increased with increasing dose, while their mean size and size distribution was relatively insensitive to neutron dose. It is suggested that the formation of visible dislocation loops was predominantly a nucleation and growth process, while in-cascade vacancy clustering may be significant in Mo. Neutron irradiation reduced the temperature and strain rate dependence of the yield stress, leading to radiation softening in Mo at lower doses. Irradiation had practically no influence on the magnitude and the temperature and strain rate dependence of the plastic instability stress. 相似文献
105.
Morten E. Simonsen Camilla S?nderby Zheshen Li Erik G. S?gaard 《Journal of Materials Science》2009,44(8):2079-2088
This article presents the results of an investigation of the compositional and structural features of an inorganic polymer
synthesized from amorphous silica and KOH. The inorganic polymers were characterized using Fourier transformation infrared
spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and X-ray diffraction (XRD).
FT-IR investigation of the inorganic polymers showed that an increase in the hydroxide concentration used in the synthesis
shifts the position of the maximum absorbance of Si–O bands toward lower wave numbers, indicating the transformation of Q4 units to Q3 and Q2 units. XPS investigation of the inorganic polymers showed that the total amount of oxygen and potassium present in the sample
increased when higher concentrations of hydroxide were used in the synthesis. The O/Si ratio of the inorganic polymers changed
from 2 to 2.6 when the KOH concentration was increased from 0.75 to 4 M. The increase in the O/Si ratio can be explained by
the greater dissolution of SiO2 particles leading to the formation of branched polymers and gelation. 相似文献
106.
A new business model for accelerating the introduction of electric vehicles into private transport systems involves the provision by an Electric Recharge Grid Operator (ERGO) of an intelligent rechargeable network in advance of the vehicles themselves. The ERGO business model creates a market for co-ordinated production and consumption of renewable energy. The innovative contribution of the model rests in its ability to combine two problems and thereby solve them in a fresh way. One problem derives from utilizing power grids with a substantial increase in renewable electric energy production (as witnessed in the Danish case with wind energy) and managing the resulting fluctuating supply efficiently. The other problem concerns finding ways to reduce CO2 emissions in the transport sector. The ERGO business model effectively solves both problems, by transforming EVs into distributed storage devices for electricity, thus enabling a fresh approach to evening out of fluctuating and unpredictable energy sources, while drastically reducing greenhouse gas emissions. This integrated solution carries many other associated benefits, amongst which are the possibility of introducing vehicle-to-grid (V2G) distributed power generation; introducing IT intelligence to the grid, and creating virtual power plants from distributed sources; and providing new applications for carbon credits in the decarbonisation of the economy. The countries and regions that have signed on to this model and are working to introduce it in 2009–2011 include Israel, Denmark, Australia, and in the US, the Bay Area cities and the state of Hawaii. 相似文献
107.
Farah Perveen Mughal Ann Christina Bergmann Ha Uyen Buu Huynh Sarah Hyllekvist Jrgensen Inaam Mansha Meliha Kesmez Patrick Mark Schürch Alexandre Pierre Andr Theocharides Paul Robert Hansen Tina Friis Morten Orebo Holmstrm Evaldas Ciplys Rimantas Slibinskas Peter Hjrup Gunnar Houen Nicole Hartwig Trier 《International journal of molecular sciences》2022,23(12)
Myeloproliferative Neoplasms (MPNs) constitute a group of rare blood cancers that are characterized by mutations in bone marrow stem cells leading to the overproduction of erythrocytes, leukocytes, and thrombocytes. Mutations in calreticulin (CRT) genes may initiate MPNs, causing a novel variable polybasic stretch terminating in a common C-terminal sequence in the frameshifted CRT (CRTfs) proteins. Peptide antibodies to the mutated C-terminal are important reagents for research in the molecular mechanisms of MPNs and for the development of new diagnostic assays and therapies. In this study, eight peptide antibodies targeting the C-terminal of CRTfs were produced and characterised by modified enzyme-linked immunosorbent assays using resin-bound peptides. The antibodies reacted to two epitopes: CREACLQGWTE for SSI-HYB 385-01, 385-02, 385-03, 385-04, 385-07, 385-08, and 385-09 and CLQGWT for SSI-HYB 385-06. For the majority of antibodies, the residues Cys1, Trp9, and Glu11 were essential for reactivity. SSI-HYB 385-06, with the highest affinity, recognised recombinant CRTfs produced in yeast and the MARIMO cell line expressing CRTfs when examined in Western immunoblotting. Moreover, SSI-HYB 385-06 occasionally reacted to CRTfs from MPN patients when analysed by flow cytometry. The characterized antibodies may be used to understand the role of CRTfs in the pathogenesis of MPNs and to design and develop new diagnostic assays and therapeutic targets. 相似文献
108.
S?ren?Emil?S?rensenEmail author Michael?R.?Hansen Morten?K.?Ebbesen Ole??.?Mouritsen 《Structural and Multidisciplinary Optimization》2012,45(6):907-916
Poor dynamics owing to polygon action is a known concern in mechanical applications of closed articulated chains. In this
paper a kinematic model of the polygon action in large chains of loop-sorting-systems is proposed. Through optimization techniques
the chain dynamics is improved by minimizing the polygon action using a parametric model of the track layout as design variables.
Three formulations of the kinematic polygon action are tested on an average sized planer tracks layout to find a superior
model. Verification of the proposed optimization method is performed using a state-of-the-art multi-body simulation model
of the chain dynamics. 相似文献
109.
Xue Yan Cui Benedicte Stavik Bernd Thiede Per Morten Sandset Sandip M. Kanse 《International journal of molecular sciences》2022,23(22)
Factor-VII-activating protease (FSAP) is involved in the regulation of hemostasis and inflammation. Extracellular histones play a role in inflammation and the conversion of latent pro-FSAP into active FSAP. FSAP has been shown to regulate endothelial permeability, but the mechanisms are not clear. Here, we have investigated the effects of FSAP on endothelial permeability in vitro. A mixture of histones from calf thymus stimulated permeability, and the wild-type (WT) serine protease domain (SPD) of FSAP blocked this effect. WT–SPD–FSAP did not influence permeability on its own, nor that stimulated by thrombin or vascular endothelial growth factor (VEGF)-A165. Histones induced a large-scale rearrangement of the junction proteins VE-cadherin and zona occludens-1 from a clear junctional distribution to a diffuse pattern. The presence of WT–SPD–FSAP inhibited these changes. Permeability changes by histones were blocked by both TLR-2 and TLR4 blocking antibodies. Histones upregulated the expression of TLR-2, but not TLR-4, in HUVEC cells, and WT–SPD–FSAP abolished the upregulation of TLR-2 expression. An inactive variant, Marburg I (MI)–SPD–FSAP, did not have any of these effects. The inhibition of histone-mediated permeability may be an important function of FSAP with relevance to sepsis, trauma, and stroke and the need to be investigated further in in vivo experiments. 相似文献
110.
Vinni Kragbæk Damborg Søren Krogh Jensen Marianne Johansen Morten Ambye-Jensen Martin Riis Weisbjerg 《Journal of dairy science》2019,102(10):8883-8897
The objective of the current study was to examine the effect of fibrous pulp and partial substitution of soybean meal with green protein concentrate from biorefining of grass–clover on dry matter intake, milk production, digestibility, and eating behavior in dairy cows compared with untreated grass–clover silage and soybean meal. Biorefining of grass–clover occurred right after harvest in a production-scale twin-screw press. The twin-screw pressing separated the grass–clover into a pulp and a green juice. The green juice was fermented using lactic acid bacteria for protein precipitation and then decanted, and the precipitate was heat dried to constitute the green protein concentrate. From the same field, grass–clover was harvested 6 d later due to rainy weather and was prewilted before ensiling. The pulp and the grass–clover were ensiled in bales without additives. The production trial consisted of an incomplete 6 × 4 Latin square trial (3-wk periods; 12 wk total) including 36 lactating Holstein cows. The trial had 6 treatments in a 2 × 3 factorial design with 2 forage types (grass–clover silage and pulp silage) and 3 protein treatments (low protein, high protein with soybean meal, and high protein with a mixture of soybean meal and green protein). The trial was designed to test silage type, protein type, protein level, and the interaction between protein level and silage type. The forage:concentrate ratio was 55:45 in low protein total mixed rations (TMR) and 51:49 in high protein TMR. Low protein and high protein TMR were composed of 372 and 342 g/kg of DM of experimental silages, respectively, and green protein supplemented TMR was composed of 28.5 g/kg of DM of green protein. Silage type did not affect dry matter intake of cows. The average energy-corrected milk yield was 37.0 and 33.4 kg/d for cows fed pulp silage and grass–clover silage, respectively, resulting in an improved feed efficiency in the cows receiving pulp silage. Milk fat concentration was greater in milk from cows fed pulp silage, and milk protein concentration was lower compared with milk from cows fed grass–clover silage. The in vivo digestibility of crude protein and neutral detergent fiber was greater for pulp silage diets compared with grass–clover silage diets. Eating rate was greater, whereas daily eating duration was lower, for pulp silage diets compared with grass–clover silage diets. The partial substitution of soybean meal with green protein did not affect dry matter intake, milk yield, or eating behavior. The in vivo digestibility of crude protein in green protein supplemented diets was lower compared with soybean meal diets. The results imply that extraction of protein from grassland plants can increase the value of the fiber part of grassland plants. 相似文献