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排序方式: 共有858条查询结果,搜索用时 15 毫秒
1.
Roberto C. Dante Pablo Martín-Ramos Pedro Chamorro-Posada Dario Rutto José Vázquez-Cabo Denisse G. Dante 《Fullerenes, Nanotubes and Carbon Nanostructures》2020,28(7):533-540
AbstractIn this work, a new g-C3N4-based Z-scheme with γ-Fe2O3 and β-Ag2Se both n-type semiconductors, and graphite to favor electron exchange is presented. The composite material was studied by XRD, FTIR, UV-Vis, TEM, XPS, TGA, DSC and TOF-SIMS, and the ability of this photocatalytic system to act as a photo-reductant was assessed using crystal violet (CV+) dye. Solar light driven photo-reduction of CV+ in the presence of tri-sodium citrate evidenced a synergistic enhancement of the activity of the composite toward reduction, with ~20 times higher conversion rates per unit of surface area than those of g-C3N4. Photo-oxidation experiments under Xe lamp irradiation in the presence of H2O2 also showed that the AgFeCN composite featured a higher activity (~8×) than g-C3N4. This Z-scheme may deserve further study as a photo-reductant to obtain hydrogen or hydrogenated compounds. Moreover, the use of CV+ may represent a facile procedure that can aid in the selection of new photocatalysts to be used in hydrogen production. 相似文献
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3.
Summary In this study, new hydrogels in rod shape were prepared from N-acryloyl-TRIS(hydroxymethyl)aminomethane (NAT) using ethylene glycol dimethacrylate (EGDMA) or N,N’methylenebisacrylamide (BIS) as crosslinking agent, dimethylformamide (DMF) as solvent and benzoyl peroxide (BPO) as initiator. In most cases, 2-hydroxyethyl methacrylate (HEMA), acrylamide (Aam) or acrylic acid (Aac) were used as co-monomers. The polymeric matrices obtained by free radical polymerization exhibited different properties by changing crosslinker, crosslinker concentration, co-monomer and initial NAT/co-monomer mole ratio. Besides, hydrogels from HEMA, Aam and Aac with BIS in absence of NAT were prepared under the same experimental reaction conditions in order to compare the properties of these products with those synthesized from NAT and the respective co-monomers. Some of the final products were selected to perform urea release assays, conducted through swelling-controlled release. Urea was chosen as “model” plant fertilizer agent. 相似文献
4.
Anthony Hendrikus Overmars Dario John Toncich 《International Journal of Flexible Manufacturing Systems》1994,6(4):311-331
This paper presents a critical evaluation of existing FMS architectures and the academic and industrial design and development strategies used during their formulation. The paper seeks to address the need for, and value of, existing architectures within the industrial arena. More importantly however, this paper puts forward a new two-tier distributed control architecture for FMS based upon new (real-time) networkable DSP servo control methodologies developed by one of the authors for Softronics in Australia. The ramifications of these methodologies are substantial, not only in terms of FMS control, but in the overall simplification of such systems and the development of flexible fixturing devices over the coming decade. This paper also postulates on how new FMS architectures can be developed from such technologies and details why such architectures could be more appropriate to industry needs than those that are currently in existence. 相似文献
5.
Dario Pasini Luigi Garlaschelli Elza Bontempi Laura E. Depero 《Fullerenes, Nanotubes and Carbon Nanostructures》2007,15(5):367-378
The synthesis of a series of polymers and cyclopolymers bearing crown ethers of differing structure and affinities towards primary ammonium ions is discussed. These polymers have been tested in their efficiency to form structurally homogeneous thin films when blended with an amphiphilic C60 compound containing a primary ammonium ion functional group. The X-ray reflectivity characterization of the films revealed that the polymer bearing the crown ether with the least affinity for primary ammonium ions, but having the highest degree of polymerization, is the most effective in forming structurally homogeneous thin films. 相似文献
6.
From "macro" to "micro" manipulation: models and experiments 总被引:1,自引:0,他引:1
A. Menciassi A. Eisinberg I. Izzo P. Dario 《Mechatronics, IEEE/ASME Transactions on》2004,9(2):311-320
This paper addresses various problems related to manipulation in the micro domain, a field which is increasingly important for research and application. Grasping and manipulating parts with size ranging between a few micrometers and about 1 millimeter (defined in this paper as "micro parts") are required for an increasing number of applications: the assembly of micro systems and micro machines; and the operation in tiny and unpredictable environments, such as for inspection and interventions in pipes and for micro surgery. The aim of this work is to find out similarities and differences between traditional manipulation and micro manipulation, by investigating which requirements are still valid and which must be redefined when the object size scales down. The similarities between the two application domains "macro" and "micro" are pointed out along with the differences, and both are taken into account for the evaluation of different grasping typologies. Dedicated models for the adhesion forces arising at the micro level are presented, preliminarily tested, and discussed. 相似文献
7.
The energy balance is discussed for the complex case of bronze or marble statuary horses and particularly the four horses of San Marco in Venice. Having computed the coefficient of exchange between bronze and the atmosphere, the daytime overheating is evaluated for different seasons and orientations of the statues. The equations can be solved with reasonable approximation and both the past and future overheatings can be evaluated as a function of the growing surface weathering and blackening. Therefore, the present analysis points out the chief characteristics of both the diurnal cycle and the variation over the centuries of the response of the bronzes to atmospheric variables. 相似文献
8.
Genovese V. Guglielmelli E. Mantuano A. Ratti G. Sabatini A.M. Dario P. 《Electronics letters》1995,31(8):632-633
The authors describe their approach to the design of redundant proximity sensor systems that are capable of extracting geometrical information about the surrounding environment and perceiving other relevant features of the reflecting objects, e.g. colour. Potential applications of the proposed sensorial systems are in the field of robotics and autonomous mobility 相似文献
9.
Ivan Rodero Hariharasudhan Viswanathan Eun Kyung Lee Marc Gamell Dario Pompili Manish Parashar 《Journal of Grid Computing》2012,10(3):447-473
Virtualized datacenters and clouds are being increasingly considered for traditional High-Performance Computing (HPC) workloads that have typically targeted Grids and conventional HPC platforms. However, maximizing energy efficiency and utilization of datacenter resources, and minimizing undesired thermal behavior while ensuring application performance and other Quality of Service (QoS) guarantees for HPC applications requires careful consideration of important and extremely challenging tradeoffs. Virtual Machine (VM) migration is one of the most common techniques used to alleviate thermal anomalies (i.e., hotspots) in cloud datacenter servers as it reduces load and, hence, the server utilization. In this article, the benefits of using other techniques such as voltage scaling and pinning (traditionally used for reducing energy consumption) for thermal management over VM migrations are studied in detail. As no single technique is the most efficient to meet temperature/performance optimization goals in all situations, an autonomic approach that performs energy-efficient thermal management while ensuring the QoS delivered to the users is proposed. To address the problem of VM allocation that arises during VM migrations, an innovative application-centric energy-aware strategy for Virtual Machine (VM) allocation is proposed. The proposed strategy ensures high resource utilization and energy efficiency through VM consolidation while satisfying application QoS by exploiting knowledge obtained through application profiling along multiple dimensions (CPU, memory, and network bandwidth utilization). To support our arguments, we present the results obtained from an experimental evaluation on real hardware using HPC workloads under different scenarios. 相似文献
10.