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排序方式: 共有414条查询结果,搜索用时 15 毫秒
21.
This paper investigates the forces correlated with environmental innovations (EIs) introduced by firms in local production systems (LPS). The role of inter-firm network relationships, agglomeration economies and internationalization strategies is jointly analysed for a sample of 555 firms in the Emilia–Romagna (ER) region (North-East Italy). Cooperating with a certain kind of local actors—i.e. suppliers and universities—is the most important EI driver for the investigated firms, along with their training coverage and their adoption of information and communication technologies. The role of agglomeration economies is instead less clear-cut. They spur EIs only in the presence of established LPS, with idiosyncratic sector specialization, while conversely they act as EI barriers. Networking effects and agglomeration economies are instead found to strongly promote the adoption of EIs by multinational firms, thus highlighting the importance of local–global interactions. Interesting specifications for these results are found for particular kinds of EIs, in such fields as CO2 abatement and ISO labelling, generally extending the analysis of EI drivers by joining local and international factors. In addition, the role of regulatory sector factors confirms the induced innovation hypothesis and provides a robustness check to our results. 相似文献
22.
This paper presents an electronic system for a fast DNA label-less detection. The sensitivity of the capacitive sensor in use is improved by depositing an insulating self-assembled monolayer (SAM) over the golden electrodes. The capacitance shift due to the hybridization effect is monitored by means of a charge-sensitive amplifier and digitalized by means of a comparator and a counter. The read-out solution demonstrates the ability to identify a 0.01% variation on the capacitive value of the sensor. Results from measurements with the optimized sensor show the reliability of the electronics. The investigated solution is suitable for monolithic systems or for a micro-fabricated array of sensors. An example of the integrated front-end is described and performances and noise evaluation are reported here. 相似文献
23.
Marcelo A. V. Souza Luiz Claudio de Santa Maria Marcos A. S. Costa Wang S. Hui Luciana C. Costa Hiram C. Araujo Filho Sandro C. Amico 《Polymer Bulletin》2011,67(2):237-249
Phosphinic-derivative poly(styrene-co-divinylbenzene)-based on PS–DVB copolymers with different porosity degrees have been
prepared by aromatic electrophilic substitution reaction using PCl3/AlCl3 followed by base-promoted hydrolysis. The phosphorylation reaction was analyzed by infra-red spectroscopy (FTIR), scanning
electron microscopy (SEM), and thermogravimetry (TG/DTG). In addition, the phosphorous content of the phosphorylated copolymers
was determined by spectrophotometry using the method based on sodium molybdate reactant so that the extension of that modification
could be assessed. The performance of the phosphorylated resins in the extraction of Pb2+ from aqueous solutions in a batch system was also evaluated. The Pb2+ content was determined by atomic absorption spectrometry (AAS). These materials presented excellent extraction capacity under
the contact time of 30 min and pH 6. 相似文献
24.
Rogério Fernandes Brito Solidônio Rodrigues de Carvalho Sandro Metrevelle Marcondes de Lima e Silva João Roberto Ferreira 《International Communications in Heat and Mass Transfer》2009
This work studies the heat influence in cutting tools considering the variation of the coating thickness and the heat flux. K10 and diamond tools substrate with TiN and Al2O3 coatings were used. The numerical methodology utilizes the ANSYS® CFX software. Boundary conditions and constant thermo physical properties of the solids involved in the numerical analysis are known. To validate the proposed methodology an experiment is used. The TiN and Al2O3 coatings did not show satisfying results during a continuous cutting process. It showed a slight reduction in the heat flux for the 10 (µm) TiN and Al2O3 coatings. 相似文献
25.
Sandro Zampieri 《Multidimensional Systems and Signal Processing》1991,2(2):101-126
In this paper an attempt is made to provide a proper formalization to the partial realization problem for discrete linear causal shift invariant 2-D systems. The approach falls into the class of 2-D Padé approximations; the results, however, are new, since the rational representation matches all the samples of a 2-D partial sequence. The realization algorithm, though characterized by a high complexity, exhibits a recursive structure and allows for a good computational economy. 相似文献
26.
What predicts psychological resilience after disaster? The role of demographics, resources, and life stress. 总被引:1,自引:0,他引:1
Bonanno George A.; Galea Sandro; Bucciarelli Angela; Vlahov David 《Canadian Metallurgical Quarterly》2007,75(5):671
A growing body of evidence suggests that most adults exposed to potentially traumatic events are resilient. However, research on the factors that may promote or deter adult resilience has been limited. This study examined patterns of association between resilience and various sociocontextual factors. The authors used data from a random-digit-dial phone survey (N = 2,752) conducted in the New York City area after the September 11, 2001, terrorist attack. Resilience was defined as having 1 or 0 posttraumatic stress disorder symptoms and as being associated with low levels of depression and substance use. Multivariate analyses indicated that the prevalence of resilience was uniquely predicted by participant gender, age, race/ethnicity, education, level of trauma exposure, income change, social support, frequency of chronic disease, and recent and past life stressors. Implications for future research and intervention are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
27.
Semantic web services are gaining more attention as an important element of the emerging semantic web. Therefore, testing semantic web services is becoming a key concern as an essential quality assurance measure. The objective of this systematic literature review is to summarize the current state of the art of functional testing of semantic web services by providing answers to a set of research questions. The review follows a predefined procedure that involves automatically searching 5 well-known digital libraries. After applying the selection criteria to the results, a total of 34 studies were identified as relevant. Required information was extracted from the studies and summarized. Our systematic literature review identified some approaches available for deriving test cases from the specifications of semantic web services. However, many of the approaches are either not validated or the validation done lacks credibility. We believe that a substantial amount of work remains to be done to improve the current state of research in the area of testing semantic web services. 相似文献
28.
Sandro Matosevic Nicolas Szita Frank Baganz 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(3):325-334
OVERVIEW: Over the last decade, the utility of immobilized microfluidic enzyme reactors (IMERs) has been demonstrated in a wide variety of fields, including medical diagnostics and therapy, biosensors, organic synthesis, drug discovery and many other applications. Of particular interest to the pharmaceutical industry is the potential for high throughput experimentation afforded by these systems, with a view to combinatorial synthesis for drug discovery applications. This article will focus on the current state of IMER systems, including immobilization techniques and microchannel flow generation, with a particular emphasis on applications and future prospects in view of likely directions and market potential of this field. IMPACT: The numerous advantages of attaching enzymes to a solid support, such as reuse of a single batch of enzyme, improved stability and durability, the ability to stop the reaction rapidly by removing the product from the reaction solution and the absence of enzyme contamination of the product are some of the attractive features of such systems. There are, however, a number of issues requiring careful consideration when developing such microsystems, including, but not limited to, surface modifications and exact control of fluid behaviour in microchannels, detection limitations, increased integration, and the reusability of the chips. APPLICATIONS: IMERs have received wide, including commercial, application as diagnostic tools for point‐of‐care applications, and, increasingly, as analytical tools in early drug development. Furthermore, peptide mapping and proteomics have employed IMER systems extensively over the past decade and growth in these areas continues. Copyright © 2011 Society of Chemical Industry 相似文献
29.
Fábio J.B. Brum Sandro C. Amico Ivo Vedana Jaime A. Spim 《Journal of Materials Processing Technology》2009,209(7):3166-3171
Autoclave processing is commonly used nowadays for dewaxing in the investment casting process. However, since the use of microwave is steadily growing in industrial processes and the wax interacts with the electromagnetic energy of the microwaves, the present work studies the possibility of carrying out dewaxing via microwave. The wax (mineral wax, vegetable resin, low molecular-weight polymer and anti-oxidant) used in this work was prepared by melting in an oven equipped with a mineral oil bath. The chemical and structural stability of the wax were monitored throughout 12 simulated dewaxing cycles, via various analyses, namely, volumetric expansion, hardness, Fourier transform infrared spectroscopy, ultraviolet–visible spectrophotometry, differential scanning calorimetry and viscosity. The results showed that microwave dewaxing is viable, significantly decreasing the incorporation of dirt and water, which is inevitable in the autoclave dewaxing process. 相似文献
30.
Tom Bocchino Sandro D‘Angelo 《电子产品世界》2001,(22):23-24,27
引言
ST最新推出的M50FW040固件集线器,采用了被称作‘低引脚数接口规范’或LPC的新主板互连协议。LPC总线是主板芯片组和单板外设功能之间的高速接口。…… 相似文献