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951.
Alexander Hammerschmidt Nikolaos Boukis Elena Hauer Eckhard Dinjus Tommy Larsen 《Fuel》2011,90(2):555-562
The purpose of the work presented here is the production of liquid biofuels from wet organic waste matter in a continuous one-step catalytic process under hydrothermal conditions. The catalytic reaction of wet organic matter at near-critical water conditions (T > 300 °C, p > 22.1 MPa) is used to produce a mixture of combustible organics which can be used as liquid biofuel. In order to achieve a good product quality in a continuous one-step process, two catalysts were applied, a homogeneous potassium carbonate catalyst and a heterogeneous ZrO2 catalyst. In addition, the reaction mixture was recirculated. The continuous flow of concentrated waste biomass feed at low flow rates and recirculation of the hot reaction mixture were the most challenging obstacles to overcome. The scale of the plant (0.1 l reactor volume) allowed for a variation of the feed, reaction temperature, and recirculation rate in order to optimise the process conditions. Still, the product quantity obtained was sufficient to perform a analytical characterisation. The experimental results confirmed the feasibility of the process. Hydrothermal treatment of waste biomass, after dewatering, resulted in a biocrude oil of high calorific value. 相似文献
952.
Fatouros DG Power K Kadir O Dékány I Yannopoulos SN Bouropoulos N Bakandritsos A Antonijevic MD Zouganelis GD Roldo M 《Nanoscale》2011,3(3):1218-1224
We have previously demonstrated that chitosan derivative N-octyl-O-sulfate chitosan (NOSC), which presents important pharmacological properties, can suspend single walled carbon nanotubes (SWNTs) up to 20 times more effectively than other chitosan derivatives in an aqueous environment. In an attempt to further investigate the impact of different molecular weights of chitosan to the solubilization and anticoagulant properties of these hybrids an array of NOSC derivatives varying their molecular weight (low, medium and high respectively) was synthesised and characterised by means of FT-IR spectroscopy, NMR spectroscopy and thermal gravimetric analysis (TGA). Microwave and nitric acid purified SWNTs, characterised by FT-IR spectroscopy, transmission electron microscopy (TEM) and Raman spectroscopy, were colloidally stabilised by these polymers and their anticoagulant activity was assessed. The results revealed that the low molecular weight NOSC coated SWNTs exhibit the highest activity when 0.5 mg mL(-1) NOSC solutions are used, activity which is similar to that of the free polymer. Preliminary studies by exposure of these hybrids to Brine Shrimp (Artemia) cysts revealed no effect on the viability of sub-adult Artemia. Our findings suggest the possibility of tailoring these nanomaterials to bear the required properties for application as biocompatible building blocks for nanodevices including biosensors and biomaterials. 相似文献
953.
f-Value: measuring an article’s scientific impact 总被引:1,自引:0,他引:1
Eleni?FragkiadakiEmail author Georgios?Evangelidis Nikolaos?Samaras Dimitris?A.?Dervos 《Scientometrics》2011,86(3):671-686
The f-value is a new indicator that measures the importance of a research article by taking into account all citations received,
directly and indirectly, up to depth n. The f-value considers all information present in a Citation Graph in order to produce a ranking of the articles. Apart from
the mathematical equation that calculates the f-value, we also present the corresponding algorithm with its implementation,
plus an experimental comparison of f-value with two known indicators of an article’s scientific importance, namely, the number
of citations and the Page Rank for citation analysis. Finally, we discuss the similarities and differences among the indicators. 相似文献
954.
A multicriteria satisfaction analysis approach in the assessment of operational programmes 总被引:1,自引:0,他引:1
Pandelis G. Ipsilandis George Samaras Nikolaos Mplanas 《International Journal of Project Management》2008,26(6):601-611
Ex-post evaluation European Operational Programmes could provide useful information and knowledge that can be used as a guide in future planning.The different concerns of the operational programme stakeholders along with the operating constraints make programme evaluation a difficult and fuzzy task. This paper presents the application of concepts and methodologies of multicriteria data analysis to identify critical success and risk factors in achieving the strategic objectives of a programme. The MUSA (multicriteria satisfaction analysis) method was used for analyzing the satisfaction of project managers with respect to satisfaction criteria associated with four dimensions: the project’s results, the operations of the programme organization, the support of the project organization and the performance of the project team.The specific case study refers to a sample of projects in the Operational Programme for Education and Initial Training in Greece which was funded by the 3rd Common Support Framework. The results show that the proposed methodology can be a valuable tool for programme organizations, especially in the case of “soft” action projects where the deliverables are intangible and project management at beneficiary organizations is provided at an ad-hoc basis. 相似文献
955.
Tombros N Buit L Arfaoui I Tsoufis T Gournis D Trikalitis PN van der Molen SJ Rudolf P van Wees BJ 《Nano letters》2008,8(9):3060-3064
The charge transport properties of single superconducting tin nanowires encapsulated by multiwalled carbon nanotubes have been investigated by multiprobe measurements. The multiwalled carbon nanotube protects the tin nanowire from oxidation and shape fragmentation and therefore allows us to investigate the electronic properties of stable wires with diameters as small as 25 nm. The transparency of the contact between the Ti/Au electrode and nanowire can be tuned by argon ion etching the multiwalled nanotube. Application of a large electrical current results in local heating at the contact which in turn suppresses superconductivity. 相似文献
956.
957.
Nikolaos Stamatis John S Arkoudelos 《Journal of the science of food and agriculture》2007,87(6):1164-1171
The self‐life, quality and safety of refrigerated sardine fillets (Sardina pilchardus) were determined at 3 °C in atmospheric air, vacuum and modified atmosphere (50% CO2/50% N2) packaging conditions. Microbiological, physico‐chemical and sensory parameters were utilised as quality indicators. The microbial flora of sardine comprised—according to order of occurrence—Shewanella putrefaciens, pseudomonads, Brochothrix thermosphacta, lactic acid bacteria and, finally, Enterobacteriaceae. Bacteria grew most quickly in sardines stored in air, followed by those in vacuum packaging, and the lowest counts were found in modified atmosphere packaging. The concentrations of moisture, ash, protein, fat and polyunsaturated fatty acids were not affected during the storage period compared to the pH values and the concentrations of lactate and ammonia that showed significant differences. Copyright © 2007 Society of Chemical Industry 相似文献
958.
Bone J Archer M Barraclough D Eggleton P Flight D Head M Jones DT Scheib C Voulvoulis N 《Environmental science & technology》2012,46(7):3687-3696
In many countries there are policies in place that impact on soils, but very few legislative or policy tools specifically for the protection of soil. Recent EU legislative proposals on soil protection have been met with opposition on the grounds of excessive cost and resource demands. With the need for evidence based policy, and recognition that involving the public in environmental monitoring is an effective way of increasing understanding and commitment, there has been growing interest in soil surveys. In addition, it is accepted that the success of environmental policies depends greatly on how effectively scientists, regulators, stakeholders, and society communicate. This paper presents the Open Air Laboratories (OPAL) Soil and Earthworm Survey as an example of public participation in soil surveys that aims to integrate the above. It is demonstrated how such surveys generate data that can be used to prioritise soil assessment, in order to address some of the concerns and objections to soil protection policies. Lessons from this pilot study in England highlight that with strategic planning of civic participation activities, this approach can deliver improvements in the quality of the evidence collected and allow for effective public involvement in policymaking and implementation, on top of direct educational benefits. 相似文献
959.
Zacharias Papanikolaou Magdalini Hatzikamari Panayiotis Georgakopoulos Minas Yiangou Evanthia Litopoulou‐Tzanetaki Nikolaos Tzanetakis 《Journal of food science》2012,77(5):M298-M306
Abstract: Isolates (47) of lactobacilli from 5 different productions of Melichloro cheese were examined for potential use as adjunct cultures. The sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE) of whole‐cell proteins classified 29 isolates as L. paraplantarum and 18 as L. paracasei subsp. paracasei. Randomly amplified polymorphic DNA‐polymerase chain reaction (RAPD‐PCR) analysis differentiated the L. paraplantarum and L. paracasei subsp. paracasei isolates at strain level and both, RAPD analysis and whole‐cell protein profiling provided useful information about the diversity of nonstarter lactic acid bacteria (NSLAB) in the different cheese productions. The isolates were slow acidifiers and about 70% of them degraded, preferentially αs‐casein. The amounts of amino acids accumulated in the milk increased with the incubation time. A similar enzyme profile was exhibited by strains of both species, except for α‐mannosidase and α‐fucosidase, which were not detected in the L. paracasei subsp. paracasei strains. All strains grew in the presence of bile at 0.3% and the majority was able to withstand pH 2.5 and pancreatin at 0.1%. Moreover, all strains reduced cholesterol in vitro, with higher removal ability recorded for strains of L. paraplantarum. A narrow spectrum of antibacterial activity was recorded for 88% of the strains. Selected isolates with appropriate technological and interesting in vitro intestinal challenges could be used as adjuncts and deserve further studies. Practical Application: Strains selected by this study could be used as adjuncts to make the Melichloro cheese. Their contribution to cheese flavor is then going to be studied to select the most appropriate. Of course these strains have to be also studied for their probiotic potential, to say that we have a probiotic food. 相似文献
960.
I Geornaras H Yang S Manios N Andritsos KE Belk KK Nightingale DR Woerner GC Smith JN Sofos 《Journal of food science》2012,77(9):M539-M544
Abstract: The decontamination efficacy of 6 chemical treatments for beef trimmings were evaluated against Escherichia coli O157:H7 and 6 non‐O157 Shiga toxin‐producing E. coli (nSTEC) serogroups. Rifampicin‐resistant 4‐strain mixtures of E. coli O157:H7 and nSTEC serogroups O26, O45, O103, O111, O121, and O145 were separately inoculated (3 to 4 log CFU/cm2) onto trimmings (10 × 5 × 1 cm; approximately 100 g) fabricated from beef chuck rolls, and were immersed for 30 s in solutions of acidified sodium chlorite (0.1%, pH 2.5), peroxyacetic acid (0.02%, pH 3.8), sodium metasilicate (4%, pH 12.5), Bromitize® Plus (0.0225% active bromine, pH 6.6), or AFTEC 3000 (pH 1.2), or for 5 s in SYNTRx 3300 (pH 1.0). Each antimicrobial was tested independently together with an untreated control. Results showed that all tested decontamination treatments were similarly effective against the 6 nSTEC serogroups as they were against E. coli O157:H7. Irrespective of pathogen inoculum, treatment of beef trimmings with acidified sodium chlorite, peroxyacetic acid, or sodium metasilicate effectively (P < 0.05) reduced initial pathogen counts (3.4 to 3.9 log CFU/cm2) by 0.7 to 1.0, 0.6 to 1.0, and 1.3 to 1.5 log CFU/cm2, respectively. Reductions of pathogen counts (3.1 to 3.2 log CFU/cm2) by Bromitize Plus, AFTEC 3000, and SYNTRx 3300 were 0.1 to 0.4 log CFU/cm2, depending on treatment. Findings of this study should be useful to regulatory authorities and the meat industry as they consider nSTEC contamination in beef trimmings. Practical Applications: Findings of this study should be useful to: (i) meat processors as they design and conduct studies to validate the efficacy of antimicrobial treatments to control pathogen contamination on fresh beef products; and (ii) regulatory agencies as they consider approaches for better control of the studied pathogens. 相似文献