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71.
The rates of CO and CO/CO2 hydrogenation at 4.2 MPa and 523 K are reported for a series of Cu/SiO2 catalysts containing 2 to 88 wt.% Cu. These catalysts were prepared on a variety of silica sources using several different Cu deposition techniques. In CO/CO2 hydrogenation, the rate of methanol formation is proportional to the exposed Cu surface area of the reduced catalyst precursor, as determined by N2O frontal chromatography. The observed rate, 4.2×10–3 mole CH3OH/Cu site-sec, is within a factor of three of the rates reported by others over Cu/ZnO and Cu/ZnO/Al2O3 catalysts under comparable conditions. These results suggest that the ZnO component is only a moderate promoter in methanol synthesis. Hydrogenation of CO over these catalysts also gives methanol with high selectivity, but the synthesis rate is not proportional to the Cu surface area. This implies that another type of site, either alone or in cooperation with Cu, is involved in the synthesis of methanol from CO. 相似文献
72.
73.
Sylwia Nowakowska Aneliia Wäckerlin Ignacio Piquero‐Zulaica Jan Nowakowski Shigeki Kawai Christian Wäckerlin Manfred Matena Thomas Nijs Shadi Fatayer Olha Popova Aisha Ahsan S. Fatemeh Mousavi Toni Ivas Ernst Meyer Meike Stöhr J. Enrique Ortega Jonas Björk Lutz H. Gade Jorge Lobo‐Checa Thomas A. Jung 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(28):3757-3763
74.
Breast Cancer Therapy: Defined Host–Guest Chemistry on Nanocarbon for Sustained Inhibition of Cancer (Small 42/2016) 下载免费PDF全文
75.
lvaro Hernez Albert Sanllorente Olga Castaer Miguel . Martínez‐Gonzlez Emilio Ros Xavier Pint Ramn Estruch Jordi Salas‐Salvad Dolores Corella ngel M. Alonso‐Gmez Lluis Serra‐Majem Miquel Fiol Jos Lapetra Enrique Gmez‐Gracia Rafael de la Torre Rosa‐María Lamuela‐Ravents Montserrat Fit 《Molecular nutrition & food research》2019,63(6)
76.
Consequence analysis to determine the damage to humans from vapour cloud explosions using characteristic curves 总被引:1,自引:0,他引:1
Alonso FD Ferradás EG Sánchez Tde J Aznar AM Gimeno JR Alonso JM 《Journal of hazardous materials》2008,150(1):146-152
The aim of this paper is to provide a methodology to facilitate consequence analysis for vapour cloud explosions (VCE). Firstly, the main PROBIT equations to evaluate direct damage on humans from those accidents (eardrum rupture, death due to skull fracture, death due to whole body impact and lung damage) are discussed and the most suitable ones are selected. Secondly, a new methodology is developed to relate characteristic overpressure-impulse-distance curves for VCE, obtained in a previous paper (F. Diaz Alonso et al., Characteristic overpressure-impulse-distance curves for vapour cloud explosions using the TNO Multi-Energy model, J. Hazard. Mater. A137 (2006) 734-741) with the selected PROBIT equations. This methodology allows the determination of damage as a function of distance to the accident's origin in only one step, using explosion energy and VCE Multi-Energy charge strength as input parameters. 相似文献
77.
Javier Montero-de-Paz Ion Oprea Vitaly Rymanov Sebastian Babiel Luis Enrique García-Muñoz Alvydas Lisauskas Matthias Hoefle Álvaro Jimenez Oleg Cojocari Daniel Segovia-Vargas Merih Palandöken Tolga Tekin Andreas Stöhr Guillermo Carpintero 《Journal of Infrared, Millimeter and Terahertz Waves》2013,34(3-4):251-266
The millimeter-wave spectrum above 70 GHz provides a cost-effective solution to increase the wireless communications data rates by increasing the carrier wave frequencies. We report on the development of two key components of a wireless transmission system, a high-speed photodiode (HS-PD) and a Schottky Barrier Diode (SBD). Both components operate uncooled, a key issue in the development of compact modules. On the transmitter side, an improved design of the HS-PD allows it to deliver an output RF power exceeding 0 dBm (1 mW). On the receiver side, we present the design process and achieved results on the development of a compact direct envelope detection receiver based on a quasi-optical SDB module. Different resonant (meander dipole) and broadband (Log-Spiral and Log-Periodic) planar antenna solutions are designed, matching the antenna and Schottky diode impedances at high frequency. Impedance matching at baseband is also provided by means of an impedance transition to a 50 Ohm output. From this comparison, we demonstrate the excellent performance of the broadband antennas over the entire E-band by setting up a short-range wireless link transmitting a 1 Gbps data signal. 相似文献
78.
Organochlorine pesticide contamination in three bird species of the Embalse La Florida water reservoir in the semiarid midwest of Argentina 总被引:3,自引:0,他引:3
Organochlorine pesticides (OCs) have a variety of acute and chronic pathological effects on animals, are persistent in the environment and are accumulated in adipose tissue of animals. In Argentina there are few studies reporting the OC contamination in the fauna. Moreover, no data are available for an ecologically relevant region, the arid-semiarid midwest region of Argentina. Recently, it was reported OC contamination in the water of an important artificial water reservoir of this area, the Embalse La Florida in the San Luis province. The present study aims to provide OC baseline data for birds of Embalse La Florida and to evaluate the potential risk of OC contamination for the local avifauna. We selected two fish-eating species, Podiceps major (great grebe) and Phalacrocorax brasilianus (neotropic cormorant) and one omnivore species, Pitangus sulphuratus (great kiskadee) to evaluate OC contamination. Alpha-, beta-, delta- and gamma-hexachlorocyclohexane (SigmaHCH), p,p'-DDT, p,p'-DDD, p,p'-DDE and methoxychlor (SigmaDDT), aldrin, dieldrin, endrin and endosulfan (SigmaALD) and, cis-chlordane, trans-chlordane, heptachlor, heptachlor epoxide(SigmaCHL) were measured in adipose tissue of two male great grebes, six neotropic cormorant (3 of each sex) and four great kiskadees (2 of each sex). We detected all OC pesticides assayed [SigmaHCH range: ND to 3168.41 ng/g fat, SigmaCHL range: ND to 4961.66 ng/g fat, SigmaALD range: 287.07 to 9161.70 ng/g fat, SigmaDDT range: 1068.98 to 6479.84 ng/g fat], with the exception of p,p'-DDT. Summed OC concentration in all bird species ranged from 2684.91 to 19231.91 ng/g fat. The omnivore had significantly greater concentrations of SigmaCHLs than fish-eating species. Females of the neotropic cormorant had significantly higher amounts of SigmaHCH and SigmaCHL than males. The OC concentrations detected in birds were lower than those reported in the literature that are associated with deleterious effects on survival or reproduction in others species of birds. This study is the first report of OC contamination in birds of the midwest region of Argentina and constitutes a starting point for future studies that evaluate temporal changes of OCs in birds in this region. 相似文献
79.
Romário Mauricio Urbanetto Nogueira Carlos Enrique Niño Bohórquez Igor Giacomelli Zanella 《Welding International》2017,31(3):161-172
Despite their similarity, the MIG/MAG and Tubular Electrode processes display particular features with regard to arc stability and variability in the characteristics of the beads. Thus, selection of one of these processes for a specific application will have to consider how these particular features affect the quality of the welds. To support this choice, the present study aimed to investigate how changing the average current affects the stability and regularity of metal transfer in welds carried out with constant voltage and pulsed current and compare the variability in the geometry and dilution of these welds. To achieve these aims, automatic welding was carried out, with steel ABNT 1020 as base metal and wire AWS ER70S-6 and AWS E71T-1 as filler metals. Besides the welds with variation in the average current, the tests involved determination of the parameters for occurrence of stable short circuiting, drop and pulsed transfer. The results showed that the voltage that gives the highest stability in short circuiting transfer is independent of the welding speed and increases with the wire speed, and also showed that welds made with hollow wire displayed greater variability compared to solid wire. 相似文献
80.
Rodrigo Pascual Matías Siña Gabriel Santelices Milton Román Enrique López Droguett 《国际生产研究杂志》2017,55(23):6946-6956
Nowadays, service economy efficiencies are key to keep competitiveness and increase market advantages. The development of Product-Service Systems (PSS) can be an interesting strategy as they seek to improve the business performance of all the participants in the value chain. This paper proposes a novel reliability-based reward scheme for use-oriented PSS contracts. In a PSS instead of paying for the product, the client pays a fee for its performance. The contribution of this work to the existing literature is to provide a quantitative tool for the development of a use-oriented PSS contract based on non-repairable component reliability and risk sharing. It can be extended to other performance metrics such as availability and reliability. A well designed PSS achieves a mutual growth agreement for the client and the supplier if it aligns their interests through channel coordination. This is achieved by balancing the improvement in the expected cost and profit for the client and the supplier, respectively. The improvement is measured with respect to a baseline scenario where no PSS contract exists. The methodology is tested using a case study that analyses mining haul truck tires. The results show a significant overall improvement in the main key performance indicators and environmental impact of the value chain. 相似文献