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Abstract

The present study thoroughly evaluated the effect of hydroxypropyl-β-cyclodextrin (HP-β-CD) on eluting of Aroclor1242 (one kind of PCBs (polychlorinated biphenyls)) from contaminated soil. The factors that might affect eluting efficiency including HP-β-CD concentration, contact time, eluting cycles, temperature, pH, salt content, humic acid, and ultrasonic were all tested to evaluate the PCBs eluting efficiency by HP-β-CD. Results indicated that Aroclor1242 can be eluted effectively from soil by HP-β-CD solution, 81% of Aroclor1242 was eluted from soil by 50 g/L of HP-β-CD solution after three cycles eluting, and the eluting efficiency was improved by increasing temperature and with ultrasonic. Furthermore, it was shown that the humic acid and extreme acidic/alkaline condition both decreased the eluting efficiency. In addition, column eluting experiment was conducted to simulate the practical HP-β-CD eluting of Aroclor1242 from contaminated soil, 18% of the PCBs was eluted from the soil column by 10 g/L of HP-β-CD. Overall, the results indicated the high extract power of HP-β-CD toward PCBs polluted soil and potential use of HP-β-CD for in situ remediation of PCBs contaminated soils.
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Authors and Affiliations

Xun Liu
1
Ning Ding
2
Hong Liu
1
Houwang Chen
1

  1. Suzhou University of Science and Technology, China
  2. Beijing Technology and Business University, China
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Abstract

Satellite-based irrigation performance is a valuable tool for improving yields in irrigated areas across the world and requires adequate land for long-term development. This study aimed to increase irrigation performance and yield gap variation of rainfed crops using the database of FAO’s Water Productivity Open Access Portal (WaPOR) and the Global Yield Gap Atlas. The evapotranspiration ( ET) performance of irrigation is expressed in equity ( CV of ET), reliability, adequacy ( CV of ET), and water productivity (kg∙m<sup>-3</sup></p>). The rainfed crops are interpreted in terms of metric tonnes/ha. Specifically, 20,325 km<sup>2</sup></p> of suitable pastoral land across eight sub-classes was converted to rainfed rice, sugarcane, maize, and vegetable crops. Results showed that the R<sup>2</sup></p> value was 0.97 at Baro Itang and –0.99 at Sor Metu, with the Baro Gambella sub-catchment having the largest yield gap of 4.435.2, 8.870.4, and 10.080∙106 kg when the yield increased by 1/3, 2/3, and 3/4. On the other hand, Gumero Gore had the smallest yield gap of 10,690, 29,700, and 33,750 kg, respectively. The management regime was 2.87, 0.87, and 0.35 kg∙m<sup>-3</sup></p> for growers in the estate, farmer association, and individual, respectively. The study concludes that no single irrigation technique can be considered the best, and a thorough analysis of spatiotemporal variation of the irrigation performance indicators and the yield gap in the water-scarce lower Baro watershed is required.

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Authors and Affiliations

Fiseha Befikadu Deneke
1
ORCID: ORCID
Amba Shetty
2
ORCID: ORCID
Fekadu Fufa
3
ORCID: ORCID

  1. National Institute of Technology Karnataka, Department of Water Resources and Ocean Engineering, 575025, Surathkal, India
  2. National Institute of Technology Karnataka, Surathkal, India
  3. Jimma Institute of Technology, Faculty of Civil and Environmental Engineering, Jimma University, Jimma, Ethiopia
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Abstract

Nowadays, the best castings’ manufacturers have to meet very demanding requirements and specifications applicable to mechanical properties and other characteristics. To fulfill those requirements, more and more sophisticated methods are being used to analyze the internal quality of castings. In many cases, the commonly used Non-Destructive Methods, like X-ray or ultrasonic testing, are not enough to ensure precise and unequivocal evaluation. Especially, when the properties of the casting only slightly fail the specification and the reasons for such failures are very subtle, thus difficult to find without the modern techniques. The paper presents some aspects of such an approach with the use of Scanning Electron Microscopy (SEM) to analyze internal defects that can critically decrease the performance of castings. The paper presents the so-called bifilm defects in ductile and chromium cast iron, near-surface corrosion caused by sulfur, micro-shrinkage located under the risers, lustrous carbon precipitates, and other microstructure features. The method used to find them, the results of their analysis, and the possible causes of the defects are presented. The conclusions prove the SEM is now a powerful tool not only for scientists but it is more and more often present in the R&D departments of the foundries.
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Authors and Affiliations

J. Jezierski
1
ORCID: ORCID
M. Dojka
1
M. Stawarz
1
ORCID: ORCID
R. Dojka
2

  1. Department of Foundry Engineering, Silesian University of Technology, 7 Towarowa, 44-100 Gliwice, Poland
  2. ODLEWNIA RAFAMET Sp. z o.o., 1 Staszica, 47-420 Kuźnia Raciborska, Poland
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Abstract

CFD technique was used to determine the effect of a stent-graft spatial configuration and hematocrit value on blood flow hemodynamic and the risk of a stent-graft occlusion. Spatial configurations of an endovascular prosthesis placed in Abdominal Aortic Aneurysm (AAA) for numerical simulations were developed on the basis of AngioCT data for 10 patients. The results of calculations showed that narrows or angular bends in the prosthesis as well as increased hematocrit affects blood flow reducing velocity and WSS which might result in thrombus development.

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Authors and Affiliations

Andrzej Polańczyk
Marek Podyma
Ludomir Stefańczyk
Ireneusz Zbiciński
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Abstract

Dans la tradition sémitologique le problème du «bilitèrisme ou «trilitérisme» de la racine consonantique est traité d’habitude avec la réconstruction linguistique des unités parentes. Ici on propose de traiter le processus de la «triconsonantisation» de la racine consonantique comme un résultat de l’action des facteurs morphologiques: le paradigme verbal et le paradigme de la flexion «interne».

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Authors and Affiliations

Anna Belova

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