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Number of results: 7
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Abstract

The results of investigations in the field of CO2 storage in water-bearing horizons in the area of the Upper Silesian Coal Basin were presented. It has been stated that the CO2 injection process will appear in the area of the storage site and beyond its boundaries. The determination of protective zones for underground CO2 storage and other structural elements, e.g. big tectonic zones, was proposed. These zones will constitute a safety buffer between the underground storage site and utilitarian undertakings conducted in its neighbourhood. In the work the proposal of CO2 injection intensification through controlled fracturing of formations of the future storage site was presented. This action should increase the CO2 injection effectiveness, especially in rock series characterised by average values of reservoir parameters.
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Authors and Affiliations

Eleonora Solik-Heliasz
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Abstract

The aim of this acoustic study is to analyse the phoneme [t] produced by school children surgically operated on for the cleft palate or cleft lip, in order to examine their vocal characteristics, to provide speech therapists with numerous concrete analyses of voice and speech, to effectively support them and to prevent some serious outcomes on their psychological and academic development. The motivation for this study was mainly stemming from the difficulties that Algerian schoolchildren with clefts encounter in the pronunciation of this phoneme. To carry out the study, several acoustic parameters were investigated in terms of the fundamental frequency F0, the first three formants F 1, F 2, and F 3, the energy E 0, the Voice Onset Time (VOT), the durations [CV] and [V] of the subsequent vowel [a]. For the analysis, further important parameters in the field of pathological speech were deployed, namely the degree of disturbance of F 0 (jitter), the degree of disturbance of intensity (shimmer) and the HNR (Harmonics to Noise Ratio). Results revealed disturbance in the values of F 1, F 2, and F 3 and stability in the values of F 0. Another important reported aspect is the increase in the value of the VOT due to the difficulties in controlling the plosives’ successive closure and release.
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Authors and Affiliations

Khaled Baazi
1 2
Mhania Guerti
1

  1. Signal and Communications Laboratory, National Polytechnic School (ENP), 1El-Harrach Algiers, 16200 Algeria
  2. Scientific and Technical Research Centre for the Development of the Arabic Language (STRCDAL), BP 225 Rostomia Algiers, 16011 Algeria
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Abstract

Strawberry plants showing symptoms of leaf spots and petiole lesions were collected from El Qalubya governorate, which is one of the most famous areas that extensively grows strawberry in Egypt. The objectives of this study were to isolate and characterize the causal pathogen of the disease. The isolated pathogen was identified as Paramyrothecium roridum (formerly known as Myrothecium roridum) based on its morphological characteristics and sequencing the partial rDNA internal transcribed spacer (ITS). A pathogenicity test using detached leaf assay revealed that P. roridum is a potential pathogen of strawberry. Symptoms started as small necrotic areas which expanded rapidly to macerate whole leaflets and petioles. In advanced stages of infection, dark olive green sporodochia were clearly distinguished on the infected tissues. Six strawberry cultivars showed different levels of susceptibility to P. roridum. Florida was the most resistant cultivar while Beauty, Camarosa, Fortuna and Sweet Charlie were susceptible. Festival showed a moderate level of susceptibility. An in vitro assay on the effect of the liquid culture filtrate of P. roridum on strawberry leaves showed that the filtrate caused damage to tissues and clear necrotic symptoms were developed. High performance liquid chromatograph (HPLC) analysis on the filtrate of 10 day old P. roridum culture revealed the presence of various mycotoxins. The two major toxins detected were 8-alpha-hydroxyroridin H and myrothecin A in addition to other trichothecenes. Data also revealed the capability of P. roridum to produce polygalacturonase (PG) and cellulase (Cx) enzymes in liquid cultures. The activity of PG was found to be significantly correlated with the age of the growth culture. This is the first record of P. roridum on strawberry in Egypt.

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Authors and Affiliations

Maali Shaker Soliman
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Abstract

In order to enhance bioactive properties of titanium 99.2 used in implantology and various biomedical applications, numerous methods to form tight oxide coatings are being investigated. Some of these interesting techniques for generating TiO2 coatings include: electrochemical methods with anodizing, electric discharge treatment, plasma methods (PVD) and diffusive methods (i.e. oxidation in a fluidized bed). Each method aims to create a thin homogenous oxide coating characterized with thermal stability and repassivation ability in the presence of body fluid environment. However, new methods are still sought for increasing the biocompatibility of the substrate following a change in the intensity of depositing on the oxide coating compounds with high biocompatibility with body tissues, including hydroxyapatite, which constitutes the basis for subsequent osseointegration processes. The article presents investigation of HAp formation on titanium substrate surface after hybrid oxidation process. Hybrid surface treatments combine methods of fluidized bed atmospheric diffusive treatment FADT with the PVD surface treatment realized with different parameters (FADT – 640°C / 8h and PVD – magnetron sputtering with TiO2 target). In order to investigate the effects of hybrid oxidation and the formation of HAp molecules, SEM-EDS, SEM-EBSD, STEM-EDS, RS, nanoindentation and Kokubo bioactivity tests (c-SBF2) were carried out. The hybrid method of titanium oxidation, proposed by the Author, presents a new outlook on the modification and development of the properties of oxide coatings in the area of biomedical applications. Combining the ways of Ti Grade 2 oxidation in the hybrid method highly improves the formation of hydroxyapatite compounds and shows the potential of applying such a technique in implantology, where the intensive growth of bone tissues is crucial.

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Authors and Affiliations

J.J. Jasinski
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Abstract

Scanning electron microscopy (SEM) is a perfect technique for micro-/nano-object imaging [1] and movement measurement [2, 3] both in high and environmental vacuum conditions and at various temperatures ranging from elevated to low temperatures. In our view, the magnetic field expanding from the pole-piece makes it possible to characterize the behaviour of electromagnetic micro- and nano electromechanical systems (MEMS/NEMS) in which the deflection of the movable part is controlled by the electromagnetic force. What must be determined, however, is the magnetic field expanding from the e-beam column, which is a function of many factors, like working distance (WD), magnification and position of the device in relation to the e-beam column. There are only a few experimental methods for determination of the magnetic field in a scanning electron microscope. In this paper we present a method of the magnetic field determination under the scanning electron column by application of a silicon cantilever magnetometer. The micro-cantilever magnetometer is a silicon micro-fabricated MEMS electromagnetic device integrating a current loop of lithographically defined dimensions. Its stiffness can be calibrated with a precision of 5% by the method described by Majstrzyk et al. [4]. The deflection of the magnetometer cantilever is measured with a scanning electron microscope and thus, through knowing the bias current, it is possible to determine the magnetic field generated by the e-beam column in a defined position and at a defined magnification.

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Authors and Affiliations

Karolina Orłowska
Maria E. Mognaschi
Krzysztof Kwoka
Tomasz Piasecki
Piotr Kunicki
Andrzej Sierakowski
Wojciech Majstrzyk
Arkadiusz Podgórni
Bartosz Pruchnik
Paolo di Barba
Teodor Gotszalk
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Abstract

The production of biofuels using wastewater as a microalgae culture medium is a little explored technology, but with potential for success. In order to contribute to the knowledge of these technologies and their technical feasibility for microalgae growth, in this work the Chlorella sp. strain was cultivated in two types of effluents generated in an experimental farm located in eastern Colombia, before and after a biological treatment process. The consumption of the main nutrients that regulate growth and lipid production was evaluated, in order to extract, quantify, characterize and convert them into biodiesel. The results showed that Chlorella sp. growth and lipid production is more favourable in R2 medium of treated water than in R1 medium of raw water, mainly due to phosphorus limitation and higher N-NO3 concentration in R2 compared to R1. In the R2 medium culture, a percentage of 42.54% of long-chain fatty acids was found, which is necessary to obtain a high quality biodiesel. Finally, the best transesterification experiment allowed reaching a fatty acid methyl esters (FAME) percentage of 90.1 ± 2.7%. In general, the results demonstrated the potential viability of using the wastewater generated in the San Pablo farm to produce biomass with lipid content to obtain biodiesel, finding that where the concentration of nutrients, mainly nitrogen, has a great influence on the microalgal metabolism for lipid accumulation.
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Authors and Affiliations

Nestor Andres Urbina-Suarez
1
ORCID: ORCID
Andres Fernando Barajas-Solano
1
ORCID: ORCID
Janet Bibiana Garcia-Martinez
1
ORCID: ORCID
German Luciano Lopez-Barrera
1
ORCID: ORCID
Angel Dario Gonzalez-Delgado
2
ORCID: ORCID

  1. Francisco de Paula Santander University, Cúcuta, Colombia
  2. University of Cartagena, Avenida del Consulado Calle 30 No. 48-152, Cartagena, Bolívar, Colombia
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Abstract

The author of the article sets out the view of Jan Łopuski, who considers that the duty imposed by the captain of a ship to provide help to people in danger at sea can be seen to be connected with Christian values and the love of one's neighbour. He does not, however, agree with this view, and rather holds to what Stanisław Matysik said on the subject. He maintained that the duty of saving life at sea is a result of"general human solidarity." The axiology of maritime law gives rise to many questions. Maritime legislation can draw on the achievements of general axiology and oflegal studies in general. The study ofmaritime law has not assembled a language of ethical or ethical-moral norms. The community of seafarers does not exist as a type of social entity. By the same token, there do not exist ethical or moral norms that could derive from it and be realised in maritime law. It is necessary to introduce conceptual and linguistic order into the area of maritime law. Ethics can create laws, but the implementation of everything that is an ethical norm cannot be the task of the maritime legal order.
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Authors and Affiliations

Zbigniew Godecki

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