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1.

Romanian policy makers have to perceive that human intervention on river basins land cover is influencing rainfall-runoff relation and the used methodology cannot accurately estimate watershed surface flow transformations. Global water cycles and energy fluxes understanding is leading to better predictions of land atmosphere interaction and local hydro-climates evolution. The water transfer time determination from rainfall to runoff needs accurate measurements of river basins hydrological parameters. Here, we analyzed and compared the lag time value results of two different methodologies (curve number and rational methodology) used for 54 Romanian small catchment areas study. The focus of this paper is the lag time evaluation and interpretation for an effective implementation of the best methodology approach in the Romanian geographical space. Our research in small river basins was developed using remote sensing technology maps, GIS and environmental datasets in combination with field work on every drainage basin in order to assess the specific morphological features and validate the land cover typology. We found that Soil Conservation Service - Curve Number (SCS-CN) method is widely used according to USA landscape features classification, but not necessarily applicable to Romanian river basins characteristics. Our results show how the official Romanian rational methodology national standard (RNS) can be improved and the limits of SCS-CN method.

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2.
Ozonation is an innovative way to preserve high quality of seed during storage and it is an alternative to harmful organophosphorus agents. Disclosure of changes in the rapeseed oil under the influence of oxidative action of ozone on the seeds was the aim of the work and is presented for the first time. Two ozone concentrations and different length of ozonation were applied. The changes in tocopherols, phenolics, flavonoids contents, antiradical activity and oxidative stability were examined. The average vitamin E concentration was 33 mg per 100 g of oil before and 31.7 after ozonation of seeds. The average content of phenolic compounds was 14.3 mg of sinapic acid g−1 and 16.9 after the ozone treatment. Changes in the flavonoids content and antioxidant activity were observed too. Ozonation caused a decrease in the vitamin E concentration which resulted also in reducing the quenching of free radicals and reduction of oil induction time.  相似文献   
3.
A review of isolates of Neisseria meningitidis and other laboratory evidence of meningococcal infection was carried out for the period 1990-1995. Thirty-three patients with evidence of meningococcal disease were identified over the six year period. Group B organisms were the most commonly identified, but an increase in Group C has occurred and is almost equal in number. Data from clinical, laboratory and public health sources should be centralized in a National Surveillance Centre.  相似文献   
4.
5.
In this study, two techniques, namely electrospinning and needle-punching processes, were used to fabricate bioactive polycaprolactone/hydroxyapatite scaffolds with a final bilayer nano-/micro-fibrous porous structure. A hybrid scaffold was fabricated to combine the beneficial properties of nanofibers and microfibers and to create a three-dimensional porous structure (which is usually very difficult to produce using electrospinning technology only). The first part of this work focused on determining the conditions necessary to fabricate nano- and micro-fibrous components of scaffold layers. A characterization of scaffold components, with respect to their morphology, fiber diameter, pore size, wettability, chemical composition and mechanical properties, was performed. Then, the same process parameters were applied to produce a hybrid bilayer scaffold by electrospinning the nanofibers directly onto the micro-fibrous nonwovens obtained in a traditional mechanical needle-punching process. In the second part, the bioactive character of a hybrid nano-/micro-fibrous scaffold in simulated body fluid (SBF) was assessed. Spherical calcium phosphate was precipitated onto the nano-/micro-fibrous scaffold surface proving its bioactivity.  相似文献   
6.
The aim of study is the elaboration of semi‐biodegradable, multilayered tubular structures as substitutes for the reconstruction of small diameter vascular prostheses (<6 mm). The inert external layer of the prostheses will be fabricated via the melt electrospinning of poly (l ‐lactide‐co‐glycolide) (PLGA). The middle layer will be constructed from polypropylene (PP); the first prototype will be produced via melt electrospinning and the second using the melt blowing technique. The general aim of this stage of the research is the selection of a sterilisation technique that is appropriate for semi‐biodegradable, multilayered tubular structures. For this purpose, single tubular structures created via the melt electrospinning of PLGA or PP and melt blown tubular structures of PP were elaborated. The influence of steam, ethylene‐oxide (EO), and radiation sterilisation techniques on the elaborated microstructure of tubular structures was analyzed during this study. The effect of each sterilisation technique was evaluated using differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy/energy‐dispersive X‐ray spectroscopy analysis (SEM/EDS). The changes in average molecular weight (Mw) and crystallinity index (CI) of the PLGA tubular structures after EO and steam sterilisation were evaluated. The EO and steam sterilisation resulted in the complete destruction of PLGA tubular structures. Only the radiation sterilisation (accelerated electrons) did not influence on PLGA tubular structures morphology as well as thermal and chemical properties. FTIR and SEM/EDS analysis indicated that no changes in the chemical properties of PP tubular structures after each sterilisation occurred. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40812.  相似文献   
7.
The aim of research was to elaborate the non‐biodegradable (made of polypropylene (PP)) and resorbable (made of polylactide (PLA)) tubular fibrous structures for the reconstruction of the vascular vessels. For the mentioned structures design, nonconventional manufacturing techniques such as melt blown, melt electrospinning, and melt electroblowing were used. Three techniques were chosen as methods allowing on the fibrous structures manufacture containing fibers in nano‐ or submicro‐size diameter. Other advantages of free‐solvent technique use is the reduction in the clinical adverse events associated with solvent resided in the fibrous structure during the fabrication. The tubular fibrous structures of PP and PLA using above‐mentioned techniques were designed. In first stage, the analysis of the processing parameters influence on the nonbiodegradable and biodegradable tubular structures fiber diameter was performed. Subsequently, the validation step was the analysis of the influence of processing parameters on PP and PLA structural properties for each manufacturing techniques was investigated. The research results confirmed the ability of the tubular structures manufacture with various fiber diameter depending on the applied technique and processing parameters. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40147.  相似文献   
8.
Concern over the ever more rapid and widespread losses of biodiversity has instigated various remedial actions: whether in situ conservation, such as the establishment of protected areas, or ex situ, such as the conservation of germplasm in gene banks. In the past, such activities were funded and managed by the public sector; however, in recent years, public support has declined and this has spawned a growing interest in conservation opportunities that might arise from 'free-market' approaches to sustainable land use and management. The UN Convention on Biological Diversity (CBD) is the key framework for articulating policies and actions on biodiversity; however, progress in developing suitable economic and market incentives for biodiversity conservation and its sustainable use has been slow, with activities such as bioprospecting and ecotourism making some, albeit limited, headway. Given the United Nations Framework for Climate Change or United Nations Framework Convention on Climate Change's (UNFCCC's) high profile within the public and private sectors, there is some potential for using it to help advance CBD objectives and provide the much-needed economic incentives for conservation, through some of the market-based mechanisms presented under the Kyoto Protocol. Significant potential lies in the fact that many 'natural' forests and certain other ecosystems are both major stores of carbon and areas of valuable biodiversity. Thus, any attempt at conserving these areas has the potential to yield both carbon and biodiversity benefits. So far, however, the conservation of natural forests is not included in the Kyoto Protocol's definition of sinks. Instead the creation of sinks - through the establishment of fast-growing monocultures - may well lead to biodiversity losses, especially if partly degraded lands are cleared for this purpose. If real progress is to be made, our understanding of the relationship between land use and biodiversity benefits needs to be improved, and more appropriate proxies for biodiversity need to be developed. At the same time, we need to have a clear understanding of the precise nature of the potential synergies and be more able to identify possible jointaction opportunities that exist between the UNFCCC, the CBD and the Convention on Combating Desertification and other international trade and economic agreements.  相似文献   
9.
The present in vivo study determined the microbiological counts of the gingival crevicular fluid (GCF) among patients with fixed dental prostheses fabricated using three different techniques. A total of 129 subjects were divided into three study groups: first, cobalt-chrome-based, metal-ceramic prostheses fabricated by the conventional method (MC, n = 35); the second group consisted of cobalt-chrome-based, metal-ceramic prostheses fabricated by the computer-aided design and computer-aided manufacturing (CAD/CAM) technique (CC-MC, n = 35); the third group comprised zirconia-based ceramic prostheses fabricated using the CAD/CAM technique (CC-Zr, n = 35). The control consisted of 24 patients using prostheses fabricated with either MC, CC-MC, or CC-Zr. The GCF was obtained from the subjects before treatment, and 6 and 12 months after the prosthetic treatment. Bacteriological and bacterioscopic analysis of the GCF was performed to analyze the patients’ GCF. The data were analyzed using SPSS V20 (IBM Company, Chicago, IL, USA). The number of microorganisms of the gingival crevicular fluid in all groups at 12 months of prosthetic treatment reduced dramatically compared with the data obtained before prosthetic treatment. Inflammatory processes in the periodontium occurred slowly in the case of zirconium oxide-based ceramic constructions due to their biocompatibility with the mucous membranes and tissues of the oral cavity as well as a reduced risk of dental biofilm formation. This should be considered by dentists and prosthodontists when choosing restoration materials for subjects with periodontal pathology.  相似文献   
10.
Vermesi  Izabella  Richter  Franz  Chaos  Marcos  Rein  Guillermo 《Fire Technology》2021,57(3):1095-1113
Fire Technology - Natural materials like wood are increasingly used in the construction industry, making the understanding of their ignition and burning behaviour in fires crucial. The state of the...  相似文献   
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