Browse

81 - 90 of 1,729 items :

  • Chemical Engineering x
Clear All

Abstract

Herein, the photocatalytic degradation of the Congo Red (CR) and Crystal Violet (CV) dyes in an aqueous solution were discussed in the presence of an indium(III) oxide (In2O3) as optical catalyst efficiency. The caproate bidentate indium(III) precursor complex has been synthesized and well interpreted by elemental analysis, molar conductivity, Fourier transform infrared (FT-IR), UV-Vis, and thermogravimetric (TGA) with its differential thermogravimetric (DTG) studies. The microanalytical and spectroscopic assignments suggested that the associated of mononuclear complex with 1:3 molar ratio (M3+:ligand). Octahedral structure is speculated for this parent complex of the caproate anion, CH3(CH2)4COO ligand. The In2O3 NPs with nanoscale range within 10–20 nm was synthesized by a simple, low cost and eco-friendly method using indium(III) caproate complex. Indium oxide nanoparticles were formed after calcination of precursor in static air at 600°C for 3 hrs. The structural, grain size, morphological and decolorization efficiency of the synthesized NPs were characterized using the FT-IR, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and transmission electron microscopy (TEM) analyses. It was worthy mentioned that the prepared In2O3 NPs showed a good photodegradation properties against CR and CV organic dyes during 90 min.

Abstract

False flax (Camelina sativa L.) is currently under-exploited but highly promising oilseed crop. Combining Camelina’s attractive agronomic traits with its unprecedented ease for genetic engineering makes it an ideal plant chassis for biotechnology applications, in particular synthetic biology strategies. For targeted expression of transgene particularly to seeds requires identification and application of seed specific promoters. In the present study two cultivars of Camelina, namely Zuzana and Smilowska, were used for transformation at early flowering stage using the floral dip method. The plants were inoculated with Agrobacterium bearing a construct for expression of red fluorescent protein (RFP) under the control of the seed specific cruciferin promoter CRUC from Arabidopsis. Transgenic seeds and plants were identified on the basis of red fluorescence (RFP) and kanamycin resistance. Relatively high transformation efficiency of 8 % was achieved particularly for the cultivar Zuzana. However, many of regenerants exerted developmental deformations such as lack of shoot apical meristem, deformed or absent cotyledons, etc. Furthermore, the activity of the CRUC promoter was still active also in true leaves rendering this promoter as inappropriate for seed targeting of the transgene. Nevertheless, genetic transformation remains a tool for direct modulation of pathways for oil synthesis in oilseed crops.

Abstract

Nature and the environment are affected by various human industrial and/or urban discharges. Remediation for this problem requires first and foremost an in-depth analysis and an overall characterization of the intrinsic properties of the pollution-receiving environments. Secondly it is necessary to predict in these environments the behavior of dangerous chemical species (here particularly heavy metals) in the long term. This study focuses mainly on a detailed characterization of 4 soil samples sampled in vicinity of wild dump-BOULIMAT located 15 km west of the city of Bejaia-Algeria. The samples were characterised by atomic absorption spectrometry, X-ray diffraction, Fluorescence X and Infrared spectroscopy. The data showed high concentrations of metallic elements especially Zn (2,651.8 mg.kg−1) and Ni (163.44 mg.kg−1) in the soil samples. For their remediation, the stabilization/solidification (S/S) process with hydraulic binders appeared promising in reducing the polluting power of metal. This approach has considerably reduced the content of pollutants; 98 % removal was obtained for Ni and 99 % for Zn. The XRD analysis technique revealed the occurrence or absence of metallic elements in the crystallized phases.

Abstract

In this present work, vinasse, a by-product of sugarcane industry, was examined using combined treatment methods to purify it. Electrocoagulation/flocculation, ultrafiltration were applied as pre-treatment and post-treatment, respectively. The effectiveness of combined process was evaluated based on colour, turbidity and chemical oxygen demand (COD) removal. The efficiency of electrochemical reactor was investigated according to process variables such as retention time, electrode distance and electrolyte dose. From the results, the price to treat unit vinasse is found to be 2.5 US$/m3 under optimum conditions. FT-IR analysis of sludge obtained shows the results of electro-coagulation process. Ultrafiltration as post treatment experiments showed the enhanced removal efficiency of colour (91%), turbidity (88%) and COD (85%). The results showed that electrocoagulation followed by ultrafiltration is a suitable combined technique to reduce the colour, turbidity and COD from vinasse liquid.

Abstract

One of the key reasons behind the urban sprawl process is the desire to increase the quality of life by living in “better” conditions. “Smart growth” is an alternative concept for the extensive development of the city, integrating different ways of land development in a compact manner. The main current of the work is to reflect on the quality of life in the urban areas. The aim of research is to determine ways to “heal” the spatial development of urban and suburban areas under the existing conditions of increasing urban chaos. The interpretation of living conditions for particular social groups is needed to find solutions that increase the quality of life. The background to the research is an analysis of literature on the subject, the consideration of good examples and own observations.

Abstract

The results of research into two city gates, Kłodzka and Wodna (Water), and into the Rycerska (Knight’s) Tower in Bystrzyca Kłodzka are discussed in this paper. The research into the architecture of the three structures helped review the chronology of transformations they were subjected to between the beginning of the fourteenth century and the second half of the twentieth century. The city walls, together with the two gates and the tower, were probably erected by Alderman Jakub Rücker in the first half of the fourteenth century. All the towers were probably raised and converted in the fifteenth century and in around 1568, they were topped with masonry pyramid cupolas. The work performed in the nineteenth century was aimed at restoring the damaged elements and at introducing bells to the Rycerska (Knight’s) Tower. The conservation work conducted in the years 2013–2017 resulted in the restoration of the damaged details and in the enhancement of all of the structures’ features of historical value.

Abstract

The aim of this study was to document spatial changes in the size of the Spa Park in Inowrocław from the 19th century onwards based on archival maps as well as field research and observations of the current status. Towns providing a highly specialised health resort and spa services, such as Inowrocław, need large expanses of green areas as public spaces for outdoor therapy for spa town visitors and patients. In Inowrocław, this may not be limited only to the surroundings of the greatest asset of this spa town - its graduation towers. The fascinating history of the area and planning decisions concerning green areas over the years have brought many benefits to the town, which also extend outside the scope of health resort services. This article presents the multi-faceted changes and transformations of this area along with the plans and intended uses.

Abstract

This paper focuses on architectural transformations of some post-industrial objects into sacral functions. The discussed works mainly relate to churches, chapels and parish houses of various Christian denominations, mainly Protestant. Such transformations provoke questions about the limits of acceptance for adaptation works in the context of objects associated with a religious cult. The doubts that arise are connected primarily with the theological-liturgical dimension, that means the interpretation of the sacrum space. As far as conservation work is concerned, the analysed examples confirm the thesis of high architectural potential inherent in post-industrial objects. They also show a wide spectrum of possible interferences in a given structure during the conversion process.

Abstract

Ethanol produced from renewable resources is considered as an ecological substitute for a fossil gasoline. Ethanol blended with the fossil gasoline is able to significantly change the properties of the blended fuel as polarity, conductivity, ability to absorb air humidity and ability to dissolve a high percentage of water etc. All these properties are growing with an increasing content of ethanol and all of them can cause higher corrosivity of blended fuel. Material compatibility of metalic construction materials of the vehicle fuel system is also decreased in the environment of ethanol – gasoline blends (EGB’s). Furthermore, components of production, transport and storage equipment may be at risk of corrosion. EGB’s with an ethanol content of about 60% vol. show high corrosive aggressivness, especially if they are contaminated with water and trace amounts of ion, which may occur if proper storage, transport and production conditions are violated. Losses caused by corrosion of equipment may be prevented by using of suitable additive. Diethylenetriamine (DETA) can be used as such additive for the mild steel which is one of the most commonly used construction material. When DETA is used, it shows very high efficiency.

Abstract

The study of the deformation behavior of the pipeline material in conditions of loads and influences simulating the operation allows better estimation of the residual life of the pipelines and more accurate forecasting of the operating costs. The kinetics of deformation in 6 model environments simulating soil electrolytes was studied. Corrosion-mechanical tests were performed and the impact of the soil electrolyte chemical composition and the applied mechanical stresses on the corrosion behavior of the pipeline steel was studied. Significant increase in the corrosion activity of the soil electrolyte due to the synergistic effect of the corrosion-active components was found in the specified ratios of the ionic molar concentrations of sulphate and chloride ions (0.05 M: 0.1 M).