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1.
S. G. Mamedov D. M. Kuli-Zade Z. F. Alieva M. M. Musaev F. R. Mustafa 《Astronomy Reports》2016,60(9):848-852
A critical review of determinations of the number of spicules is presented, and the role of both classical and Type 2 spicules in heating and mass balance in the corona is considered. The total number of Type 2 spicules is determined, together with the upward fluxes of energy and mass to which they give rise. The total number of Type 2 spicules on the solar surface is found to be ~105, close to values obtained in other studies. The associated particle flux toward the corona is 2.5 × 1014 cm?2 s?1, an order of magnitude lower than the corresponding flux for classical spicules. The associated energy flux is 104 erg cm?2 s?1, an order of magnaitude lower than estimates obtained in other studies. The results indicate that Type 2 spicules can supply the mass lost from the corona, but are not able to fully explain coronal energy losses. 相似文献
2.
Mustafa Evren Ersahin Recep Kaan Dereli Hale Ozgun Berivan Gunes Donmez Ismail Koyuncu Mahmut Altinbas Izzet Ozturk 《洁净——土壤、空气、水》2011,39(6):543-548
Baker's yeast industry has significant effects on environment due to significant water consumption and high strength wastewater production. Effluents from baker's yeast industry are characterized by high concentrations of biological oxygen demand (BOD5), chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN), total dissolved solids (TDS), sulfate, and dark brown color. The aim of this study is to provide a detailed quantitative and qualitative identification and characterization of the wastewater sources from different processes of a baker's yeast industry. It is identified that the most polluted wastewater components of the facility are coming from rotary drum filter and evaporation process. However, the highest pollution loads is identified as tank and equipment cleaning effluent due to very high flow rate from this source. The efforts should be on the way to minimize the water usage for the tank and equipment cleaning process, and to recycle less polluted waste streams back to the process. 相似文献
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Dig-limit optimization is an operational decision making problem that significantly affects the value of open-pit mining operations. Traditionally, dig-limits have been drawn by hand and can be defined as classifying practical ore and waste boundaries suiting equipment sizes in a bench. In this paper, an optimization approach based on a genetic algorithm (GA) was developed to approximate optimal dig-limits on a bench, given grade control data, equipment constraints, processing, and mining costs. A case study was conducted on a sample disseminated nickel bench, in a two destination and single ore-type deposit. The results from using the GA are compared to hand-drawn results. The study shows that GA-based approach can be effectively used for dig-limit optimization. 相似文献
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This article contributes to a small but growing body of multi-sited and multi-scalar research on the Belt and Road Initiative.We focus on relations at the national,regional and international scales,and present original research from China and Turkey,to show how the Istanbul-Ankara high-speed railway has served as a testing ground for China's Belt and Road Initiative(BRI).Its construction was initially funded by the European Investment Bank,but it is now part of the backbone of the Turkish Government's Middle Corridor plan which enhances west-east connectivity and integration with the Caucasus and Central Asia.We show that in contrast to multinational corporations from the OECD that seek to remain footloose,Chinese state-owned enterprises(SOEs)seek to adapt to,apprehend and ultimately shape local in-stitutions.In the case of Turkey this proved difficult given its institutional alignment with the European Union.Thus,while the railway project was completed successfully by a consortium led by a Chinese SOE,Turkey's dynamic and complex regulatory environment discourages Chinese SOEs in the infrastructure sector.We conclude that the Turkish and Chinese gov-ernments are currently pursuing complementary territorial visions yet their cooperation is project-based and pragmatic. 相似文献
9.
Trace Metal Solid State Speciation in Aerosols of the Northern Levantine Basin,East Mediterranean 总被引:3,自引:0,他引:3
Mustafa Koçak Nilgun Kubilay Barak Herut Malcolm Nimmo 《Journal of Atmospheric Chemistry》2007,56(3):239-257
An established three stage sequential leach scheme was applied to a series of selected high volume aerosol samples (n = 35) collected from the Turkish Eastern Mediterranean coastline (Erdemli). Samples were selected according to their air
mass back trajectory history to reflect the contrasting mixtures of aerosol material present in the Eastern Mediterranean
marine aerosol. Two populations were adopted, those samples which were classed as “anthropogenic” and those which were “Saharan”
dominated aerosol populations. Applying the three stage leach it was possible to define the proportion for each of the considered
metals (Al, Fe, Cu, Pb, Cd, Zn and Mn) present in the (a) “exchangeable” (b) “carbonate / oxide” and (c) “refractory” phases,
representing novel solid state aerosol speciation data for this marine system. Clear trends were established, conforming with
data from previous studies with mainly crustal derived metals (Al and Fe) being present in the refractory phases (Al > 88%;
Fe > 84%) and those influenced by anthropogenic sources being dominating in the exchangeable phase, although for these metals
the variability was comparatively high (12–64%; 19–85%; 40–100% for Zn, Pb and Cd, respectively). For the majority, greater
exchangeable fractions were present the lower the crustal source contribution to the aerosol population, whereas the “refractory”
fraction exhibited contrasting behaviour. This was illustrated by the novel application of the mixing diagram, presenting
each of the three speciation stages against the corresponding percent anthropogenic contribution to each collected sample.
Zn, Pb and Cd all illustrated progressive decrease in the percent exchangeable with increasing crustal contribution to the
aerosol population. The percent exchangeable was discussed in terms of its use to represent the upper limit of the bioavailable
fraction of metal associated with the aerosol, post deposition. The mixing diagram approach enabled the prediction of the
residual fractions for Cd, Pb and Zn (41 ± 4%; 62 ± 4% and 82 ± 5%, respectively,) in Saharan end-member material. 相似文献
10.
The AMS study has been performed on various types of the basement – Variscan granitic and surrounding – Mesozoic sedimentary rocks in the Velká Fatra Mountains, Tatric Superunit of the Central Western Carpathians. The Velká Fatra Mts. provides good opportunity for AMS study because of composite S-type and I-type granite character of pluton and clear relations to Mesozoic sedimentary rocks in the cover and nappe positions. The granitic massif consists of the three types of weakly magnetic peraluminous granites (350 – 340 Ma in age), ranging from two-mica granites to biotite granodiorites in composition and carrying accessory monazite and ilmenite; whereby they resemble common S-type and/or Ilmenite Series granite. This pre-existing granitic body was intruded by relatively young (304 Ma old) metaluminous to subaluminous, strongly magnetic (due to magnetite) tonalitic intrusion of the I-type and/or Magnetite Series granite. In all S-types investigated as well as in the I-type tonalite body, the magnetic fabrics are not uniform, but slightly variable within a body and differing from body to body. The magnetic fabrics in all granitic rocks can be classified as mostly magmatic in origin, only subordinately affected by ductile deformation. The Alpine overprint of the magnetic fabric of the Variscan granite frequent in the central areas of the Central Western Carpathians was only weak in the Velká Fatra Mts. and the magnetic fabrics of these granites thus mostly comprise the original Variscan magmatic fabrics. On the other hand, in the marginal parts of the Velká Fatra Mts. the magnetic fabrics in granites are locally conformable to the deformational magnetic fabrics in surrounding sedimentary rocks (Mesozoic in age) thus indicating at least local effects of the Alpine deformation. The magnetic fabrics in Mesozoic sedimentary rocks covering the crystalline basement are partially (Cover Formation) to entirely (Nappe Units) deformational in origin. 相似文献