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1.
Rehman Abdul Ma Hengyun Chishti Muhammad Zubair Ozturk Ilhan Irfan Muhammad Ahmad Munir 《Environmental science and pollution research international》2021,28(14):17319-17330
Environmental Science and Pollution Research - The accelerated urbanization in China was already coupled with a steadily increasing demand for energy usage. The present study major aim was to... 相似文献
2.
Ertan Alptekin Mustafa Canakci Huseyin Sanli 《Waste management (New York, N.Y.)》2014,34(11):2146-2154
In this study, corn oil as vegetable oil, chicken fat and fleshing oil as animal fats were used to produce methyl ester in a biodiesel pilot plant. The FFA level of the corn oil was below 1% while those of animal fats were too high to produce biodiesel via base catalyst. Therefore, it was needed to perform pretreatment reaction for the animal fats. For this aim, sulfuric acid was used as catalyst and methanol was used as alcohol in the pretreatment reactions. After reducing the FFA level of the animal fats to less than 1%, the transesterification reaction was completed with alkaline catalyst. Due to low FFA content of corn oil, it was directly subjected to transesterification. Potassium hydroxide was used as catalyst and methanol was used as alcohol for transesterification reactions. The fuel properties of methyl esters produced in the biodiesel pilot plant were characterized and compared to EN 14214 and ASTM D6751 biodiesel standards. According to the results, ester yield values of animal fat methyl esters were slightly lower than that of the corn oil methyl ester (COME). The production cost of COME was higher than those of animal fat methyl esters due to being high cost biodiesel feedstock. The fuel properties of produced methyl esters were close to each other. Especially, the sulfur content and cold flow properties of the COME were lower than those of animal fat methyl esters. The measured fuel properties of all produced methyl esters met ASTM D6751 (S500) biodiesel fuel standards. 相似文献
3.
Guleryuz G Gucel S Ozturk M 《Journal of environmental biology / Academy of Environmental Biology, India》2010,31(4):503-514
Interrelations exist in the terrestrial ecosystems between the plant type and characteristics of nutrient uptake. Annual net nitrogen mineralization in soils of different plant communities in the high altitude zone of Spil mountain located in the Mediterranean phytogeographical region of Turkey was investigated throughout one year by field incubation method. Seasonal fluctuations resulting from field incubation were markedly higher in autumn and spring than summer. These are mainly associated with the changes in soil moisture being at minimum in the Mediterranean summer. A significant correlation was developed between the net Nitrate (kg NO3(-)-N ha week(-1)) production and soil water content (p<0.05; r = 0.316 in soil of 0-5 cm; r = 0.312 in soil of 5-15 cm). The results showed that the annual productivity of nitrogen mineralization shows different values depending on communities. Annual net ammonium (NH4(+)-N) production in the soils of each community was negatively estimated. However annual net nitrate (NO3(-)-N) production (0-15 cm) was higher in grassland (27.8 kg ha y(-1)) and shrub (25.0 kg ha y(-1)) than forest (12.4 kg ha y(-1)) community. While annual net N(min) values were close to each other in grassland (14.5 kg ha y(-1)) and shrub (14.1 kg ha y(-1)), but negative in forest community (-3.6 kg ha y(-1)). The reasons for these differences are discussed. 相似文献
4.
Idil Arslan-Alaton Tugba Olmez-Hanci Tugce Ozturk 《Environmental science and pollution research international》2018,25(35):34938-34949
The effect of varying inorganic (chloride, nitrate, sulfate, and phosphate) and organic (represented by humic acid) solutes on the removal of aqueous micropollutant bisphenol A (BPA; 8.8 μM; 2 mg/L) with the oxidizing agents hydrogen peroxide (HP; 0.25 mM) and persulfate (PS; 0.25 mM) activated using zero-valent aluminum (ZVA) nanoparticles (1 g/L) was investigated at a pH of 3. In the absence of the solutes, the PS/ZVA treatment system was superior to the HP/ZVA system in terms of BPA removal rates and kinetics. Further, the HP/ZVA process was not affected by nitrate (50 mg/L) addition, whereas chloride (250 mg/L) exhibited no effect on the PS/ZVA process. The negative effect of inorganic anions on BPA removal generally speaking increased with increasing charge in the following order: NO3? (no inhibition)?<?Cl? (250 mg/L)?=?SO42??<?PO43? for HP/ZVA and Cl? (250 mg/L; no inhibition)?<?NO3??<?SO42??<?PO43? for PS/ZVA. Upon addition of 20 mg/L humic acid representing natural organic matter, BPA removals decreased from 72 and 100% in the absence of solutes to 24 and 57% for HP/ZVA and PS/ZVA treatments, respectively. The solute mixture containing all inorganic and organic solutes together partly suppressed the inhibitory effects of phosphate and humic acid on BPA removals decreasing to 46 and 43% after HP/ZVA and PS/ZVA treatments, respectively. Dissolved organic carbon removals were obtained in the range of 30 and 47% (the HP/ZVA process), as well as 47 and 57% (the PS/ZVA process) for the experiments in the presence of 20 mg/L humic acid and solute mixture, respectively. The relative Vibrio fischeri photoluminescence inhibition decreased particularly for the PS/ZVA treatment system, which exhibited a higher treatment performance than the HP/ZVA treatment system. 相似文献
5.
Linda Nebiolo Mehmet Ozturk Bruno Brambati Susan Miller Jack Wands Aubrey Milunsky MD 《黑龙江环境通报》1990,10(9):575-581
The aim of this study was to determine the efficacy of combined maternal serum alpha-fetoprotein (MSAFP) and maternal serum human chorionic gonadotropin (MShCG) screening in detecting chromosome defects in the first trimester of pregnancy. Sera of 492 women (previously assayed for MSAFP) were analysed for MShCG under code without knowledge of cytogenetic results. Overall, 48 of 492 patients (9·8 per cent) had either an MSAFP multiple of the median ⩽0·5 or an MShCG β/a z ratio multiple of the median ⩽ 0·25, eight of whom had a fetus with a serious chromosome defect. A third of fetuses with Down' s syndrome and 83 per cent with trisomy 18 were detected at a potential‘cost’ of providing chorionic villus sampling or amniocentesis in 8·6 percent of women screened. 相似文献
6.
Jayant V. Deshpande Jesse Frey Omer Ozturk 《Environmental and Ecological Statistics》2006,13(1):25-40
Ranked-set sampling from a finite population is considered in this paper. Three sampling protocols are described, and procedures
for constructing nonparametric confidence intervals for a population quantile are developed. Algorithms for computing coverage
probabilities for these confidence intervals are presented, and the use of interpolated confidence intervals is recommended
as a means to approximately achieve coverage probabilities that cannot be achieved exactly. A simulation study based on finite
populations of sizes 20, 30, 40, and 50 shows that the three sampling protocols follow a strict ordering in terms of the average
lengths of the confidence intervals they produce. This study also shows that all three ranked-set sampling protocols tend
to produce confidence intervals shorter than those produced by simple random sampling, with the difference being substantial
for two of the protocols. The interpolated confidence intervals are shown to achieve coverage probabilities quite close to
their nominal levels. Rankings done according to a highly correlated concomitant variable are shown to reduce the level of
the confidence intervals only minimally. An example to illustrate the construction of confidence intervals according to this
methodology is provided. 相似文献
7.
Evaluation of PCDD/F levels in ambient air and soils and estimation of deposition rates in Kocaeli, Turkey 总被引:1,自引:0,他引:1
PCDD/F analyses were made in soil and ambient air samples taken from Kocaeli, an industrialized area of Turkey. Results showed that the levels of PCDD/F pollution are comparable to the levels observed in the various urban areas in the world. PCDD/F concentrations in surface soils ranged between 0.4 and 4.27 pg I-TEQ kg(-1) with a geometric mean of 0.76 pg I-TEQ kg(-1), while those in ambient air were between 23 and 563 f gm(-3), with geometric mean of 82.0 f gm(-3). Ambient air PCDD/F concentration in the city center was about 10 times higher than those in the rural area. Combustion activities present in the area were assessed to be the most significant source of the PCDD/F pollution based on the congener and homologue profiles and statistical analysis of the data. The deposition rate modeling of USEPA was applied and the deposition rates were determined in the range between 7.6 and 66.3 ng I-TEQ m(-2)year(-1) with a geometric mean of 15.9 ng I-TEQ m(-2)year(-1). The rates were higher than the recommended deposition rates in relation to the tolerable daily intake (TDI) range of PCDD/Fs for humans. The deposition velocities computed were also found to be high in both low and highly chlorinated PCDD/Fs, and this was attributed to the vapor phase deposition of volatile PCDD/Fs, and the scavenging effect of the precipitation on the particle-bound PCDD/Fs. 相似文献
8.
S. Gucel A. Guvensen M. Ozturk A. Celik 《Environmental monitoring and assessment》2013,185(1):157-169
Airborne pollen distribution in the city of Nicosia (Cyprus) was measured volumetrically during two consecutive years 2007–2008 on weekly basis using Lanzoni trap (Lanzoni VPPS 2000). A total of 7,880 pollen grains/m3 belonging to 44 taxa, in 2007 were 3,593 pollen grains/m3 and in 2008 it was 4,287 pollen grains/m3, were determined. Out of these, 25 belonged to the arboreal and 19 to the non-arboreal taxa. At the end of 2 years, total pollen counts were 78.76% arboreal, 19.32% non-arboreal, and 1.92% unidentified taxa. The number of pollen in the arboreal plants followed the trend as Pinaceae (29.96%), Cupressaceae/Taxaceae (18.33%), Olea europaea L. (6.92%), and Quercus spp. (4.92%), and for non-arboreal representatives, these were Poaceae (8.46%), Chenopodiaceae/Amaranthaceae (2.61%), Plantago spp. (1.69%), and Parietaria spp. (1.51%). The distribution of pollen in the atmosphere of Nicosia followed the trend as March, April, May, and June. 相似文献
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10.
Rehman Abdul Ma Hengyun Ahmad Munir Ozturk Ilhan Chishti Muhammad Zubair 《Environmental science and pollution research international》2021,28(24):30702-30713
Environmental Science and Pollution Research - Carbon dioxide emission and climatic variation have a detrimental influence on the atmosphere as well as on agriculture production. The key aim of the... 相似文献