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991.
介绍了Benninger公司开发的新型分条整经机Ergotee随着新一代分条整经机Ergotec的出现.分条整经机的生产顺序被成功地优化。作为分条整经机进一步发展的结果。整经质量可以随着生产率的提高而提高。更高的整经和倒轴速度,尤其是操作的真正优化使得生产时间大大减少. 相似文献
992.
Fuel cells for civil aircraft application: On-board production of power, water and inert gas 总被引:2,自引:0,他引:2
Gwénaëlle Renouard-Vallet Martin SaballusPeter Schumann Josef KalloK. Andreas Friedrich Hans Müller-Steinhagen 《Chemical Engineering Research and Design》2012,90(1):3-10
Fuel cell systems are regarded as a promising solution for future electrical energy generation on board of commercial aircraft. In addition to an improved efficiency such systems offer the opportunity of producing water usable for on-board purposes and provide additional functions such as inerting (providing a non-inflammable atmosphere) of the jet fuel tank. This paper presents an evaluation and assessment of different system architectures as well as experimental results demonstrating the feasibility of the multiple functions in a laboratory set-up. First, the conventional system requirements and the results reported by the Federal Aviation Administration (FAA) are discussed. A system design evaluation based on simulating cruise and ground operation of aircraft is performed demonstrating the benefits of systems with pressurized hydrogen tank storage and cabin air use. The requirements for a fuel cell system regarding aircraft inerting function are calculated based on the FAA analysis. Experimental results based on laboratory systems confirm the feasibility of the implementation of various functions with a single fuel cell system. Test platforms for further investigation of the systems are shortly described. 相似文献
993.
994.
Molzberger AF Vollmer G Hertrampf T Möller FJ Kulling S Diel P 《Molecular nutrition & food research》2012,56(3):399-409
Scope Exposure scenarios during different stages of development of an organism are discussed to trigger adverse and beneficial effects of isoflavones (ISO). The aim of this study was to investigate how in utero and postnatal ISO exposure modulates the estrogen sensitivity of the mammary gland and to identify the underlying molecular mechanisms. Methods and results Therefore, rats were exposed to either ISO‐free (IDD), ISO‐rich (IRD) or genistein‐rich diet (GRD), up to young adulthood. Proliferative activity (PCNA expression) in the mammary gland at different ages and the estrogen sensitivity of the mammary gland to estradiol (E2) or genistein (GEN) in adult ovariectomized animals was determined and compared with different treatments. Treatment with E2 resulted in a significant lower proliferative and estrogenic response of the mammary gland in IRD and GRD compared with IDD. This correlates to a change in the gene expression pattern and a decrease in the ratio of estrogen receptor alpha (ERα) beta (ERβ Conclusions Our results provide evidence that in utero and postnatal exposure to a diet rich in ISO but also to GEN reduces the sensitivity of the mammary gland toward estrogens and support the hypothesis that in utero and postnatal ISO exposure reduces the risk to develop breast cancer. 相似文献
995.
Particle shape is an important attribute in determining particle properties and behavior, but it is difficult to control and characterize. We present a new portable system that offers, for the first time, the ability to separate particles with different shapes and characterize their chemical and physical properties, including their dynamic shape factors (DSFs) in the transition and free-molecular regimes, with high precision, in situ, and in real-time. The system uses an aerosol particle mass analyzer (APM) to classify particles of one mass-to-charge ratio, transporting them to a differential mobility analyzer (DMA) that is tuned to select particles of one charge, mobility diameter, and for particles with one density, one shape. These uniform particles are then ready for use and/or characterization by any application or analytical tool. We combine the APM and DMA with our single-particle mass spectrometer, SPLAT II, to form the ADS and demonstrate its utility to measure individual particle compositions, vacuum aerodynamic diameters, and particle DSFs in two flow regimes for each selected shape. We applied the ADS to the characterization of aspherical ammonium sulfate and NaCl particles, demonstrating that both have a wide distribution of particle shapes with DSFs from approximately 1 to 1.5. 相似文献
996.
Samrana Kazim Shahzada Ahmad Jiri Pfleger Josef Plestil Yogesh M. Joshi 《Journal of Materials Science》2012,47(1):420-428
A simple and facile method was used to synthesize polyaniline (PANI) nanocomposites with sodium montmorillonite clay (Na+-MMT) using in situ intercalative oxidative polymerization. Aniline was admixed with Na+-MMT at various concentrations, keeping the aniline monomer in the reaction mixture constant. The intercalation of PANI into
the clay layers was confirmed by X-ray diffraction studies in conjugation with electron microscope techniques and FTIR spectra,
particularly by the narrowing of the Si–O stretching vibration band confirmed the interaction between PANI and the clay. The
employed route offers the possibility to improve the thermal properties with simultaneously controlled electrical conductivity.
Thermal studies show an improved thermal stability of the nanocomposites relative to the pure PANI. Depending on the loading
of the clay, the room temperature conductivity values of these nanocomposites varied between 2.0 × 10−4 and 7.4 × 10−4 S cm−1, with the maximum at 44 wt% PANI concentration. The decrease of electrical conductivity at high PANI concentration was ascribed
to the decrease of the structural ordering of PANI in the nanocomposite. 相似文献
997.
The Jacobi-Porstend?rfer room model, describing the dynamical behaviour of radon and radon progeny in indoor air, has been successfully used for decades. The inversion of the model-the determination of the five parameters from measured results which provide better information on the room environment than mere ratios of unattached and attached radon progeny-is treated as an algebraic task. The linear interdependence of the used equations strongly limits the algebraic invertibility of experimental results. For a unique solution, the fulfilment of two invariants of the room model for the measured results is required. Non-fulfilment of these model invariants by the measured results leads to a set of non-identical solutions and indicates the violation of the conditions required by the room model or the incorrectness or excessive uncertainties of the measured results. The limited and non-unique algebraic invertibility of the room model is analysed numerically using our own data for the radon progeny. 相似文献
998.
Cordt Zollfrank Kai GutbrodPeter Wechsler Josef Peter Guggenbichler 《Materials science & engineering. C, Materials for biological applications》2012,32(1):47-54
Serious infectious complications of patients in healthcare settings are often transmitted by materials and devices colonised by microorganisms (nosocomial infections). Current strategies to generate material surfaces with an antimicrobial activity suffer from the consumption of the antimicrobial agent and emerging multidrug-resistant pathogens amongst others. Consequently, materials surfaces exhibiting a permanent antimicrobial activity without the risk of generating resistant microorganisms are desirable. This publication reports on the extraordinary efficient antimicrobial properties of transition metal acids such as molybdic acid (H2MoO4), which is based on molybdenum trioxide (MoO3). The modification of various materials (e.g. polymers, metals) with MoO3 particles or sol-gel derived coatings showed that the modified materials surfaces were practically free of microorganisms six hours after contamination with infectious agents. The antimicrobial activity is based on the formation of an acidic surface deteriorating cell growth and proliferation. The application of transition metal acids as antimicrobial surface agents is an innovative approach to prevent the dissemination of microorganisms in healthcare units and public environments. 相似文献
999.
Carbon nanotube/graphene nanocomposite as efficient counter electrodes in dye-sensitized solar cells
We demonstrated the replacement of the Pt catalyst normally used in the counter electrode of a dye-sensitized solar cell (DSSC) by a nanocomposite of dry spun carbon multi-walled nanotube (MWNT) sheets with graphene flakes (Gr-F). The effectiveness of this counter electrode on the reduction of the triiodide in the iodide/triiodide redox (I(-)/I(3)(-)) redox reaction was studied in parallel with the use of the dry spun carbon MWNT sheets alone and graphene flakes used independent of each other. This nanocomposite deposited onto fluorinated tin-oxide-coated glass showed improved catalytic behavior and power conversion efficiency (7.55%) beyond the use of the MWNTs alone (6.62%) or graphene alone (4.65%) for the triiodide reduction reaction in DSSC. We also compare the use of the carbon MWNT/Gr-F composite counter electrode with a DSSC using the standard Pt counter electrode (8.8%). The details of increased performance of graphene/MWNT composite electrodes as studied are discussed in terms of increased catalytic activity permitted by sharp atomic edges that arise from the structure of graphene flakes or the defect sites in the carbon MWNT and increased electrical conductivity between the carbon MWNT bundles by the graphene flakes. 相似文献
1000.
Der Arbeitskreis Geotechnik der Deponiebauwerke hat in fünf Themengruppen bisher 76 Empfehlungen zur Planung, zum Bau und zur Qualitätsüberwachung von Abfalldeponien veröffentlicht. In diesem Bericht werden zwei überarbeitungen vorgestellt, eine grundsätzliche Neubarbeitung der E 2‐4, Oberflächenabdichtungssysteme und die an neuere Erfahrungen angepasste E 2‐33, Kapillarsperren in Oberflächenabdichtungen. Recommendations of the DGGT Committee “Geotechnics of Landfill Structures”. The Technical Committee ”Geotechnics of Landfill Structures” of the German Geotechnical Society published up to now 76 recommendations (GDA‐Geotechnical Landfill Recommendations) structured in 5 main issues. This paper introduces two new editions of currently important recommendations, the fundamentally reviewed E 2‐4, Capping Systems, and a new edition of E 2‐33, Capillary Barriers in Landfill Capping Systems. 相似文献