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991.
992.
Andrea Aleixandre Mauro Gisbert Jorge Sineiro Ramón Moreira Cristina M. Rosell 《Journal of food science》2022,87(6):2405-2416
993.
Mauro Bianco Gianfranco Bilardi Francesco Pesavento Geppino Pucci Bernhard A. Schrefler 《International journal for numerical methods in engineering》2003,57(13):1801-1818
Solving fully coupled non‐linear hygro‐thermo‐mechanical problems relative to the behaviour of concrete at high temperatures using monolithic models is nowadays a very interesting and challenging computational problem. These models require an extensive use of computational resources, such as main memory and computational time, due to the great number of variables and the numerical characteristics of the coefficients of the linear systems involved. In this paper, a number of different variants of a frontal solver used within HITECOSP, an application developed within the BRITE Euram III ‘HITECO’ EU project, to solve multiphase porous media problems, are presented and evaluated with respect to their numerical accuracy and performance. When developing the variants, several optimization techniques have been adopted, such as data structure, cache and branches optimizations. Specifically, numerical accuracy has been evaluated using a modified componentwise backward error analysis. The main result of this work is a new solver which is both much faster and more accurate than the original one. Specifically, the code runs over five times faster and numerical errors are reduced by up to three orders of magnitude. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
994.
The fully matrix-inversion-free artificial compressibility (AC), characteristic based split (CBS) algorithm is used to produce a stable and accurate solution for high Rayleigh number natural convection in rectangular cavities. Two benchmark problems are solved using the AC-CBS scheme: the classical differentially heated (DH) cavity, and a cavity subject to temperature boundary conditions on its sides, which is proposed here as a new benchmark. For the DH cavity problem, the dependence of the solution on the computational grid is highlighted, and it is shown how the horizontal velocity is more sensitive than the other calculated quantities. For the newly proposed benchmark, the numerical results are compared to experimental data that has recently appeared in the open literature. 相似文献
995.
Diana De Santis Mauro Moresi Anna Maria Gallo Maurizio Petruccioli 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(9):1072-1079
Monascus purpureus C322 was cultivated on well‐established production media to yield prevailingly red or orange pigment‐rich ethanolic extracts. Once these extracts had been diluted by an overall factor of 50, they were used as such to dye raw wool standard specimens differently premordanted using alum or stannic chloride. Independently of the mordant used, the specimens dyed with the red pigment‐rich extracts showed a pale red colour tending to pink, whereas the specimens dyed with the orange pigment‐rich extracts exhibited a more definite orange colour. By carrying out a few colourfastness standard tests (manual washing at 40 °C, acid and basic perspiration and hot pressing), stannic chloride‐premordanted wool specimens dyed with the red pigment‐rich extracts were found to be less resistant to acid and basic perspiration than their orange counterparts. Since the production of the orange pigment‐rich ethanolic extracts appeared to be more cost‐effective than that of their red counterparts, the former might support the present demand for colorants of natural origin in the textile sector. Copyright © 2005 Society of Chemical Industry 相似文献
996.
E.T. de Almeida A.E. Mauro A.M. Santana S.R. Ananias A.V.G. Netto J.G. Ferreira R.H.A. Santos 《Inorganic chemistry communications》2007,10(12):1394-1398
Two binuclear cyclometallated compounds [Pd(C2,N-dmba)(μ-N3)]2 (1) and [Pd2(C2,N-dmba)2(μ-N3)(μ-Cl)] (2) (dmba = N,N-dimethylbenzylamine) have been synthesized and characterized by elemental analysis, IR and NMR spectroscopies and single crystal X-ray diffraction crystallography. The ability of CH3 groups to form C(sp3)Hπ hydrogen bonds with phenyl rings is responsible for the molecular self-assembly within the crystals of 1 and 2. Compound 1 crystallizes as one-dimensional supramolecular chains whereas the crystal packing of 2 consists of a herringbone of sandwiches composed by two inversely related [Pd2(C2,N-dmba)2(μ-N3)(μ-Cl)] molecules. 相似文献
997.
Maurizio Benaglia Giuseppe Celentano Mauro Cinquini Alessandra Puglisi Franco Cozzi 《Advanced Synthesis u0026amp; Catalysis》2002,344(2):149-152
A tyrosine‐derived imidazolidin‐4‐one was immobilized on a modified poly(ethylene glycol) and converted in situ into a soluble polymer‐supported catalyst for the enantioselective Diels–Alder cycloaddition of acrolein to 1,3‐cyclohexadiene (up to 92% ee) and 2,3‐dimethyl‐1,3‐butadiene (73% ee). Catalyst recycling (up to four cycles) was accompanied by some loss of the chemical efficiency and marginal erosion of the enantioselectivity. 相似文献
998.
Mechanical behaviour of shape memory alloys for seismic applications 2. Austenite NiTi wires subjected to tension 总被引：1，自引：0，他引：1
The results of cyclic tensile tests on superelastic NiTi shape memory alloy (SMA) wires are presented and discussed. The tests were carried out within a large experimental test programme for the MANSIDE Project, with the scope of verifying the suitability of SMA superelastic wires as kernel components for seismic protection devices.The mechanical behaviour is described by means of four fundamental quantities, namely: secant stiffness, energy loss per cycle, equivalent damping and residual strain. The sensitivity to temperature and strain rate, as well as the influence of strain amplitude and the effects due to repeated cyclic deformation, are analysed in detail.The experimental results show that the characteristics of the superelastic wires are well suited for seismic applications, as both the recentring and the energy dissipating features of the devices can be easily obtained. Moreover, the influence of the investigated parameters, within their usual range of variation in seismic protection devices, is compatible with the use of superelastic wires for practical applications. 相似文献
999.
High-energy x-ray diffraction studies of metallic liquids provide valuable information about structural evolution on the atomic length scale, leading to insights into the origin of the nucleation barrier and the processes of supercooling and glass formation. The containerless processing of the beamline electrostatic levitation (BESL) facility allows coordinated thermophysical and structural studies of equilibrium and supercooled liquids to be made in a contamination-free, high-vacuum (～10(-8) Torr) environment. To date, the incorporation of electrostatic levitation facilities into synchrotron beamlines has been difficult due to the large footprint of the apparatus and the difficulties associated with its transportation and implementation. Here, we describe a modular levitation facility that is optimized for diffraction studies of high-temperature liquids at high-energy synchrotron beamlines. The modular approach used in the apparatus design allows it to be easily transported and quickly setup. Unlike most previous electrostatic levitation facilities, BESL can be operated by a single user instead of a user team. 相似文献
1000.
Over the past several decades, a lot of emerging contaminants have been detected in water and wastewater effluents. Their release should be minimized since their presence in the environment can result in toxic effects for water and human life. Many different technologies have been used to remove contaminants from drinking water; among them, filtration is one of the most commonly used methods. This study investigated the antibacterial capability of silver water filters and their potential application in the reduction of bacterial fouling and proliferation in water treatment. Poly(ether sulfone) membranes commonly used in water filtration were coated with silver nanoparticles synthesized via the in situ photoreduction method. The morphology of the coating and the distribution of silver clusters were studied by scanning electron microscopy. The amount of silver on the surface was quantified by thermogravimetric analysis, and the silver released from the substrate was analyzed through inductively coupled plasma mass spectrometry. The antibacterial capability of the silver‐treated filters was demonstrated through microbiological tests defined for the specific application on Escherichia coli, as the representative coliform bacterium and pathogenic microorganism commonly associated with contaminated drinking water. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43848. 相似文献