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1.
İsmail Hilali 《International Journal of Green Energy》2016,13(9):911-917
This study presents a comparative analysis of sizing of metal hydride tank filled with different alloys. Alloys include solid solutions and intermetallic compounds of the generic families AB5, AB2, AB, A2B. The effects of the different alloys on the sizing of metal hydride hydrogen storage tanks are complicated and depend on many factors. In this paper, a thermoeconomic optimization analysis with a simple algebraic formula was presented for the estimation of optimum metal hydride tank surface area for heat transfer enhancement. The optimum area of the metal hydride tank filled with commercially available different alloys (LaN5, Ti0,98Zr0,02V0,43Fe0,09Cr0,05Mn1,5, TiFe, Mg2NiH4) was evaluated and compared by the developed method. The optimum net savings and the value of payback were determined for four alloys. It is found that mathematical model can be employed for the determination of optimum metal hydride tank design and increasing net savings according to alloy types. The optimum areas of the tanks filled with four alloys (LaN5, Ti0,98Zr0,02V0,43Fe0,09Cr0,05Mn1,5, TiFe, Mg2NiH4) were calculated as 0.136, 0.130, 0.133, and 0.173 m2, respectively. The optimum net savings for tanks filled with four alloys (LaN5, Ti0,98Zr0,02V0,43Fe0,09Cr0,05Mn1,5, TiFe, Mg2NiH4) are about 461.0, 409.3, 419.6, and 979.6 $ and the values of payback are about 1.98, 2.1, 2.17, and 1.37 years, respectively. Excessive area of the metal hydride tank would not be as economical as the optimum tank area. Thermal management of metal hydride tank must be designed for optimum points calculated at which maximum savings occur. 相似文献
2.
Air pollution forecasting in Ankara, Turkey using air pollution index and its relation to assimilative capacity of the atmosphere 总被引:1,自引:0,他引:1
D. Deniz Genc Canan Yesilyurt Gurdal Tuncel 《Environmental monitoring and assessment》2010,161(1-4):11-27
A conditional time-averaged gradient (COTAG) system has been developed to provide direct long-term (weekly to monthly) average flux gradient measurements for a range of trace gases, between land and atmosphere. Over daily periods, atmospheric conditions can range from high stability, where the vertical gradients of ambient concentration are enhanced due to very small diffusivity, to highly unstable conditions, in which concentration gradients are small due to the intense turbulent activity of the surface layer. The large vertical gradients generated by high stability would bias the estimate of the actual flux: to avoid this, the COTAG system samples conditionally, within a carefully refined range of stability. A comparison with a continuous flux gradient system suggested that the removal of stable conditions from the sampling period does not substantially modify the evaluation of the long-term fluxes. 相似文献
3.
Zafer Ziya Öztürk Cihat Tasaltin Güleda Önkal Engin Ayşe Gül Gürek Devrim Atilla Vefa Ahsen Mahir İnce 《Environmental monitoring and assessment》2009,151(1-4):369-375
Sewage treatment works are one of the major sources that cause atmospheric odour pollution. The increase in the number of complaints about odour nuisance is due to the increase in environmental concerns. Unfortunately, the legislation on odour nuisance from sewage treatment works is very limited. In order to determine suitable thresholds on which to base legal standards, reliable and efficient odour measurement methods need to be defined. A chemical sensor array was developed for the purpose of measuring wastewater odour. This paper describes the development of the chemical sensor system which is specifically tuned to odours of wastewater origin and which can give an electronic measure of the wastewater odours. Odour emissions from a wastewater treatment facility were detected by using a quartz crystal microbalance (QCM) sensor array. The array consists of nine sensor elements, which were coated with different materials. In this paper, the usage of these novel instruments in the water industry was shown. 相似文献
4.
Adem Asan Rukiye Aydin Deniz Karsli Semiz Vildan Erci Ibrahim Isildak 《Environmental monitoring and assessment》2013,185(3):2115-2121
In this study, an ultra-sensitive and highly selective, rapid flow-injection spectrophotometric method for the determination of iron (II) and total iron has been proposed. The method was based on the reaction between iron (II) and 2′, 3, 4′, 5, 7-pentahydroxyflavone in slightly acidic solution with a strong absorption at 415 nm. The carrier solution used was 1?×?10?5 M 2′, 3, 4′, 5, 7-pentahydroxyflavone in 0.1 M HAc/Ac? buffer solution at pH 4.5. Parameters that affect simultaneously the determination of iron (II) and interfering ions were tested. The relative standard deviation for the determination of 50 μg L?1 iron (II) was 0.85 % (n?=?10), and the limit of detection (blank signal plus three times the standard deviation of the blank) was 3 μg L?1, both based on injection volumes of 20 μL. The method has been successfully applied to the determination of iron (II) and total iron in water samples and ore samples. The method was verified by analysing a certified reference material Zn/Al/Cu 43XZ3F. 相似文献
5.
Sorption of alpha and beta hydrophobic endosulfan in a Vertisol from southeast region of Turkey 总被引:1,自引:0,他引:1
Aye Dilek Atasoy Ahmet Ruhi Mermut Halil Kumbur Faruk nce Hüdaverdi Arslan Emel Deniz Avc 《Chemosphere》2009,74(11):1450-1456
Endosulfan has been applied to control numerous insects in a variety of food and non-food crops. Limited information is available on dynamics of this pesticide in the soil. The objective of this research was to determine the adsorption–desorption behavior of the alpha (α) and beta (β) endosulfan in a Vertisol from the southeast region of Turkey, where cotton is the main crop in the large irrigated lowlands. The α and β endosulfan were adsorbed considerably and Freundlich adsorption–desorption isotherms fitted the α and β endosulfan data (R2 > 0.98). Freundlich adsorption coefficients (Kf) for the α endosulfan ranged between 21.63 and 16.33 while for the β endosulfan they were between 14.01 and 17.98 for the Ap and Bw2 horizons. The difference of Kf values of α and β endosulfan for two horizons were explained with the slight difference in the amount of organic matter and clay, but considerable difference in Fe contents of the two horizons. Alpha and β endosulfan Kfd values were 118.03 and 45.81 for the Ap and 48.08 and 68.71 for the Bw2 horizons. Higher adsorption and desorption behavior of the endosulfan isomers for the same horizon was attributed to poor physical bonding between the endosulfan molecule and the surfaces of fundamental soil particles. This fact is thought to increase the effective use of endosulfan in agriculture with a possibility of its movement to the surface and groundwater in the Vertisol studied. 相似文献
6.
Buse Tuğba Zaman Emine Gülhan Bakırdere Nursu Aylin Kasa Serenay Deniz Sabriye Sel Dotse Selali Chormey Sezgin Bakırdere 《Environmental monitoring and assessment》2018,190(7):437
This study describes the determination of trace levels of copper by slotted quartz tube atomic absorption spectrometry after dispersive liquid-liquid microextraction. A ligand synthesized from the reaction of salicylaldehyde and 1-naphthylamine was used to form coordinate copper complex prior to extraction. All parameters that influence the output of complex formation, extraction, and instrumental measurement were optimized to enhance the absorbance signal of copper. Under the optimum conditions, about 104-fold enhancement in sensitivity was recorded over the conventional flame atomic absorption spectrometer, corresponding to a 0.51 ng/mL detection limit. The percent relative standard deviation calculated for the lowest concentration (4.8%) indicated high precision for the experimental procedure. Accuracy and applicability of the optimum method were determined by performing spiked recovery tests on urine, lake water, and mineral water samples. Satisfactory recovery results were obtained between 82.2 and 106.3% at four different concentrations. Matrix matching method was also performed to increase the accuracy of quantification, and the percent recovery calculated for 175 ng/mL was 105.14%. 相似文献
7.
Timur Deniz Ozer Cinar Ana C Marques C P Leslie Grady 《Water environment research》2006,78(4):340-352
The response of a mixed microbial culture to cyclic aerobic and anoxic (denitrifying) conditions was studied in a chemostat with a 48-hour hydraulic residence time receiving a feed containing benzoate and pyruvate. When the cyclic conditions were 3-hour aerobic and 9-hour anoxic, the bacteria-degraded benzoate aerobically via the catechol 2,3-dioxygenase (C23DO) pathway. The quantity of C23DO remained constant throughout the anoxic period but decreased during the initial portion of the aerobic period before returning to the level present in the anoxic period. Anoxic biodegradation of benzoate was via benzoyl-CoA reductase, which remained constant regardless of the redox condition. The aerobic benzoate uptake capability (AeBUC) of the culture increased during the aerobic period but decreased during the anoxic period. The anoxic benzoate uptake capability (AnBUC) exhibited the opposite response. When the cycle was 6-hour aerobic and 6-hour anoxic, aerobic biodegradation of benzoate proceeded via the protocatechuate 4,5-dioxygenase (P45DO) pathway. The P45DO activity decreased early in the aerobic period, but then increased to the level present during the anoxic period. The level of benzoyl-CoA reductase was constant throughout the cycle. Furthermore, AeBUC and AnBUC responded in much the same way as in the 3/9-hour chemostat. During a 9-hour aerobic and 3-hour anoxic cycle, the culture synthesized both P45DO and C23DO, with the former having significantly higher activity. Unlike the other two cycles, AeBUC changed little during the aerobic period, although AnBUC decreased. The culture was well-adapted to the cyclic conditions as evidenced by the lack of accumulation of either substrate during any cycle tested. This suggests that cyclic aerobic-anoxic processes can be used in industrial wastewater-treatment facilities receiving significant quantities of simple aromatic compounds like benzoate. However, the results showed that the kinetics of benzoate degradation were different under aerobic and anoxic conditions, a situation that must be considered when modeling cyclic bioreactors receiving aromatic compounds. 相似文献
8.
Enver Guler Deniz Ozakdag Muserref Arda Mithat Yuksel Nalan Kabay 《Environmental geochemistry and health》2010,32(4):335-339
The effect of feed seawater temperature on the quality of product water in a reverse osmosis process was investigated using
typical seawater at Urla Bay, Izmir region, Turkey. The tests were carried out at different feed seawater temperatures (11–23°C)
using two RO modules with one membrane element each. A number of variables, including pH, conductivity, total dissolved solids,
salinity, rejection percentage of a number of ions (Na+, K+, Ca2+, Mg2+, Cl−, HCO3
−, and SO4
2−), and the levels of boron and turbidities in collected permeates, were measured. The suitability of these permeates as irrigation
and drinking water was checked by comparison with water quality standards. 相似文献
9.
Colby J. Tanner Gül Deniz Salalι Andrew L. Jackson 《Behavioral ecology and sociobiology》2011,65(2):249-256
Human activity can have a large impact on surrounding ecosystems. For example, humans alter resource distributions for other
species, potentially modifying these species competitive dynamics. These changes in local competitive processes are frequently
associated with species invasions. Here, we investigate how differences in resource distribution affect competitive behaviour
using the highly invasive European shore crab (Carcinus maenas). Using a controlled laboratory experiment in combination with behaviour assays and social network analysis, we show that
individuals feeding in habitats with clumped food distributions are more aggressive than individuals feeding in habitats where
food is evenly dispersed, and this aggression is present even on days where crabs are not feeding. Additionally, this persistent
aggression can be induced, suggesting that individuals of this invasive species possess the flexibility to modify their competitive
behaviours in response to differences in food distributions. Furthermore, we show how these individual responses can lead
to changes in overall organisation of aggressive interactions within a population. We discuss these results in relation to
how human impacts can have long-term effects on competitive behavioural strategies, and how behavioural flexibility can allow
invasive species to colonise and persist in highly impacted sites such as urban ecosystems. 相似文献
10.
Hanedar Asude Çifçi Deniz İzlen Zafer Nur Görgün Erdem 《Journal of Material Cycles and Waste Management》2022,24(5):1760-1767
Journal of Material Cycles and Waste Management - In this study, the amount of medical waste generated in a high-populated city in Turkey between January 2018 and August 2021 was evaluated, and the... 相似文献