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Antioxidative effect of melatonin, ascorbic acid and N-acetylcysteine on caerulein-induced pancreatitis and associated liver injury in rats 被引量:31
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作者 Mukaddes E■refoglu Mehmet Gül +2 位作者 Burhan Ate■ Kadir Batoglu Mukadder Ay■e Selimoglu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第2期259-264,共6页
AIM: To investigate the role of oxidative injury in pancreatitis-induced hepatic damage and the effect of antioxidant agents such as melatonin, ascorbic acid and N-acetyl cysteine on caerulein-induced pancreatitis an... AIM: To investigate the role of oxidative injury in pancreatitis-induced hepatic damage and the effect of antioxidant agents such as melatonin, ascorbic acid and N-acetyl cysteine on caerulein-induced pancreatitis and associated liver injury in rats. METHODS: Thirty-eight female Wistar rats were used. Acute pancreatitis (AP) was induced by two i.p. injections of caerulein at 2-h intervals (at a total dose of 100 μg/kg b.wt). The other two groups received additional melatonin (20 mg/kg b.wt) or an antioxidant mixture containing L(+)-ascorbic acid (14.3 mg/kb.wt.) and N-acetyl cysteine (181 mg/kg b.wt.) i.p. shortly before each injection of caerulein. The rats were sacrificed by decapitation 12 h after the last injection of caerulein. Pancreatic and hepatic oxidative stress markers were evaluated by changes in the amount of lipid peroxides measured as malondialdehyde (MDA) and changes in tissue antioxidant enzyme levels, catalase (CAT) and glutathione peroxidase (GPx). Histopathological examination was performed using scoring systems. RESULTS: The degree of hepatic cell degeneration, intracellular vacuolization, vascular congestion, sinusoidal dilatation and inflammatory infiltration showed a significant difference between caerulein and caerulein+melatonin (P= 0.001), and careulein and caerulein + L(+)- ascorbic acid +N-acetyl cysteine groups (P= 0.002). The degree of aciner cell degeneration, pancreatic edema, intracellular vacuolization and inflammatory infiltration showed a significant difference between caerulein and caerulein + melatonin (P=0.004), and careulein and caerulein + L(+)-ascorbic acid +N-acetyl cysteine groups (P=0.002). Caerulein-induced pancreatic and liver damage was accompanied with a significant increase in tissue MDA levels (P= 0.01, P= 0.003, respectively) whereas a significant decrease in CAT (P= 0.002, P=0.003, respectively) and GPx activities (P= 0.002, P= 0.03, respectively). Melatonin and L(+)-ascorbic acid +N-acetyl cysteine administration significantly decreased MDA levels in pancreas (P= 0.03, P= 0.002, respectively) and liver (P= 0.007, P= 0.01, respectively). Administration of these agents increased pancreatic and hepatic CAT and GPx activities. Melatonin significantly increased pancreatic and hepatic CAT (P= 0.002, P= 0.001, respectively) and GPx activities (P=0.002, P=0.001). Additionally, L(+)-ascorbic acid+N-acetyl cysteine significantly increased pancreatic GPx (P= 0.002) and hepatic CAT and GPx activities (P= 0.001, P= 0.007, respectively) CONCLUSION: Oxidative injury plays an important role not only in the pathogenesis of AP but also in pancreatitis-induced hepatic damage. Antioxidant agents such as melatonin and ascorbic acid+N-acetyl cysteine, are capable of limiting pancreatic and hepatic damage produced during AP via restoring tissue antioxidant enzyme activities. 展开更多
关键词 CAERULEIN Liver MELATONIN Oxidative stress PANCREATITIS
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Adsorption Behavior and Inhibition Corrosion Effect of Sodium Carboxymethyl Cellulose on Mild Steel in Acidic Medium 被引量:7
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作者 BAYOL E. GüRTEN A.A. DURSUN M. KAYAKIRILMAZ K. 《物理化学学报》 SCIE CAS CSCD 北大核心 2008年第12期2236-2242,共7页
The effect of sodium carboxymethyl cellulose (Na-CMC) on the corrosion behavior of mild steel in 1.0 mol·L-1 HCl solution has been investigated by using weight loss (WL) measurement, potentiodynamic polarization,... The effect of sodium carboxymethyl cellulose (Na-CMC) on the corrosion behavior of mild steel in 1.0 mol·L-1 HCl solution has been investigated by using weight loss (WL) measurement, potentiodynamic polarization, linear polarization resistance (LPR), and electrochemical impedance spectroscopy (EIS) methods. These results showed that the inhibition efficiency of Na-CMC increased with increasing the inhibitor concentration. Potentiodynamic polarization studies revealed that the Na-CMC was a mixed type inhibitor in 1.0 mol·L-1 HCl. The adsorption of the inhibitor on mild steel surface has been found to obey the Langmuir isotherm. The effect of temperature on the corrosion behavior of mild steel in 1.0 mol·L-1 HCl with addition of 0.04% of Na-CMC has been studied in the temperature range of 298-328 K. The associated apparent activation energy (E*a ) of corrosion reaction has been determined. Scanning electron microscopy (SEM) has been applied to investigate the surface morphology of mild steel in the absence and presence of the inhibitor molecules. 展开更多
关键词 吸附行为 抑制作用 腐蚀作用 羧甲基纤维素钠 低碳钢 酸性介质
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Biosorption of Cu^(2+) and Zn^(2+) by raw and autoclaved Rocella phycopsis 被引量:7
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作者 Emine Yalcln Kltigin avusoglu Kadir Klnalloglu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第3期367-373,共7页
The behavior of Cu2+ and Zn2+ biosorption onto raw and modified Roccella phycopsis from aqueous solutions was studied. Modification process was applied by autoclavation at 121°C for 30 min. The effcts of pH, in... The behavior of Cu2+ and Zn2+ biosorption onto raw and modified Roccella phycopsis from aqueous solutions was studied. Modification process was applied by autoclavation at 121°C for 30 min. The effcts of pH, initial metal concentration and biosorbent dosage were investigated. The maximum Cu2+ biosorption was achieved at pH 5.0 and the maximum biosorption capacities of 31.5 and 37.8 mg/g were recorded for raw and modified biosorbent, respectively. In the case of Zn2+ biosorption, maximum biosorption capacities were obtained at pH 4.0 as 29.1 and 35.3 mg/g for raw and modified biosorbent, respectively. Biosorption of Zn2+ and Cu2+ on all form of R. phycopsis increased much quickly with increasing initial metal concentrations from 10 to 100 mg/L. After modification process, probable changes in the surface polarity of raw and modified R. phycopsis were investigated by contact angle measurements. As expected, R. phycopsis has a polar surface and shows a highest contact angle with water, while after autoclavation water contact angle of R. phycopsis was significantly decreased from 47.5° to 34.4°. 展开更多
关键词 BIOSORPTION Roccella phycopsis polarity contact angle measurement
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Antimicrobial activity of latex silver nanoparticles using Calotropis procera 被引量:1
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作者 Nadia Hussein Mohamed Mady Ahmed Ismail +1 位作者 Wael Moustfa Abdel-Mageed Ahmed Abdelfattah Mohamed Shoreit 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2014年第11期876-883,共8页
Objective:To synthesize silver nanoparticles(AgNPs) by green methods using scrum latex of Calotropis procera at 80 ℃ and evaluate them against bacteria,dermatophytes and phytopathogenic fungi comparing with the activ... Objective:To synthesize silver nanoparticles(AgNPs) by green methods using scrum latex of Calotropis procera at 80 ℃ and evaluate them against bacteria,dermatophytes and phytopathogenic fungi comparing with the activity of untreated latex.Methods:The synthesis of AgNPs was performed by mixing 3%latex scrum extract with the same volume of silver nitrate(2 mmol/L) solution in round flask and heating in water bath at80 ℃.Characterization of silver particles were determined using UV-vis spectrophotometer,transmission electron microscopy(TEM),X-ray diffraction and Fourier transform infrared spectroscopy.The antimicrobial activity of the green synthesized AgNPs was determined against bacteria,dermatophytes and phytopathogenic fungi and compared to the crude untreated latex by agar-well diffusion methods.Results:Biosynthesis of latex silver nanoparticles was successfully obtained by green method.The formation of AgNPs has been confirmed by UV-vis,TEM microscopy.X-ray diffraction and Fourier transform infrared spectroscopy.TEM analysis showed that synthesized AgNPs are highly stable spherical shaped particles,well dispersed with a diameter ranged from 4 nm up to 25 nm and an average size of 12.33 nm.AgNPs showed strong antibacterial activity against Gram-negative bacteria(Escherichia coli,Pseudomonas aeruginosa and Serratia sp.) and antifungal activity against Trichophyton rubrum,Candida albicans and Aspergillus terreus.Conclusions:It can be concluded that serum latex of Calotropis pmcera was found to display strong potential for the synthesis of AgNPs as antimicrobial agents through rapid reduction of silver ions(Ag^+ to Ag^0).The green synthesized AgNPs were found to show higher antimicrobial efficacy than crude latex. 展开更多
关键词 Green synthesis Calotropis procera LATEX SILVER NANOPARTICLES ANTIMICROBIAL ACTIVITY
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Recovery of Copper and Cobalt from Copper Slags as Selective 被引量:2
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作者 Uyan Yuksel Ibrahim Tegin Recep Ziyadanogullari 《Journal of Environmental Science and Engineering(A)》 2017年第8期388-394,共7页
This study focuses on the recovery of copper and cobalt from copper slags obtained from Kure district of Kastamonu city, which is in the north of Turkey, and removal of Se, Te, Sb and As from mixture of copper slag an... This study focuses on the recovery of copper and cobalt from copper slags obtained from Kure district of Kastamonu city, which is in the north of Turkey, and removal of Se, Te, Sb and As from mixture of copper slag and copper concentrate has been conducted. Homogeneous mixtures of slag/pyrite/copper concentrate rate were subjected to roasting at high temperatures in a closed medium and then it was processed roasting at air atmosphere at 600 ℃. In the leaching experiments, the effects of roasting time, rate of slag/pyrite/copper concentrate and the effect of the added iron powder to leaching on the metals dissolution were investigated. Under optimum conditions, 99.6% of copper and 98.4% of cobalt were extracted in roasting at high temperatures in a closed medium 3:6:6 of slag/pyrite/copper concentrate rate then roasting at 600 ℃ at 5 hours. Besides, it was determined that all of Se, Te, Sb and As can be removed from the mixture of slag/pyrite/copper concentrate rate. 展开更多
关键词 COPPER COBALT SLAG ROASTING PYRITE copper concentrate.
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Recovery of Copper and Cobalt from Converter Slag with a New Flotation Method Using H_(2)S 被引量:1
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作者 Ibrahim Tegin Recep Ziyadanogullar 《Journal of Environmental Science and Engineering(A)》 2018年第2期69-75,共7页
In this study,two different samples were obtained from Küre Copper factory.It was determined that the samples contain:the sample of K.C.F.(Küre Copper Factory),0.70%Cu and 0.5%Co.This sample was firstly grou... In this study,two different samples were obtained from Küre Copper factory.It was determined that the samples contain:the sample of K.C.F.(Küre Copper Factory),0.70%Cu and 0.5%Co.This sample was firstly grounded at-100 mesh dimension.Flotation was done according to previously obtained optimum flotation conditions.The flotation yield of Cu and Co in concentrate phase was found to be low by collective flotation.Even when the samples were grounded at-160 mesh,no change was observed in the flotation result.Especially,Co could not float under the flotation conditions of the non-sulfurized samples.There,a new flotation method was applied which was not applied until now.For this aim,the samples were firstly sulphurised under the steam of H2S+H2O.By this method,the amount of Cu and Co in the samples get rich.According to the obtained results,the optimum reactions for flotation and sulphurization were determined.In the first sulphurization conditions for the sample of K.C.F.,the yield of flotation for the Co and Co were found to be 98.27%and 68.07%,respectively.The results indicate that Cu can be floated at low yield in the original samples.On the other hand,Co cannot float under these conditions. 展开更多
关键词 Converter slag flotation copper COBALT sulphurization
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Fuzzy Soft Expert Set and Its Application 被引量:1
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作者 Shawkat Alkhazaleh Abdul Razak Salleh 《Applied Mathematics》 2014年第9期1349-1368,共20页
In 1999, Molodtsov introduced the concept of soft set theory as a general mathematical tool for dealing with uncertainty. Alkhazaleh and Salleh (2011) define the concept of soft expert sets where the user can know the... In 1999, Molodtsov introduced the concept of soft set theory as a general mathematical tool for dealing with uncertainty. Alkhazaleh and Salleh (2011) define the concept of soft expert sets where the user can know the opinion of all experts in one model and give an application of this concept in decision making problem. So in this paper, we generalize the concept of a soft expert set to fuzzy soft expert set, which will be more effective and useful. We also define its basic operations, namely complement, union, intersection, AND and OR. We give an application of this concept in decision making problem. Finally, we study a mapping on fuzzy soft expert classes and its properties. 展开更多
关键词 SOFT SET SOFT EXPERT SET FUZZY SOFT EXPERT SET
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Sorption of uranium(Ⅵ) from aqueous solutions by DEEA organovolcanic: isotherms, kinetic and thermodynamic studies
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作者 ümit H.Kaynar ümran Hicsonmez +1 位作者 Sermin CamKaynar Süleyman Kocak 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第2期125-135,共11页
The sorption of the uranium(VI) ions from aqueous solutions by diethylethanolammonium organovolcanics(Kula-TURKEY) was investigated under different experimental conditions. DEEA was used to modify the surface of basal... The sorption of the uranium(VI) ions from aqueous solutions by diethylethanolammonium organovolcanics(Kula-TURKEY) was investigated under different experimental conditions. DEEA was used to modify the surface of basaltic volcanics. The characteristic of basaltic volcanic was analyzed by XRF, SEM–EDS, FTIR, and XRD. The BET surface areas of unmodified volcanics and DEEA-modified volcanics were found as 2.265 and3.689 m^2/g, respectively. The volcanic samples were treated by using different concentrations of DEEA. The adsorption of U(VI) on natural and modified volcanics was examined as a function of the contact time, initial p H of the solution, initial U(VI) concentration, and temperature.Langmuir, Freundlich, and D–R adsorption isotherms were used to describe the adsorption. While examining the adsorption percentage and distribution coefficient, these values for unmodified volcanics were found to be25% ± 0.76 and 10.08 m L/g, while the values for the DEEA-modified volcanics were 88% ± 1.04 and 220 m L/g, respectively. The pseudo-first-order and pseudo-secondorder kinetic models were used to describe the kinetic data.In this study, it can be seen that the adsorption process is suitable for the pseudo-second-order kinetic model. Various thermodynamic parameters(ΔG°, ΔH°, and ΔS°) were calculated with the thermodynamic distribution coefficients obtained at different temperatures. The sorption process was a chemical adsorption process. The results indicated that the processes are spontaneous and endothermic. 展开更多
关键词 DEEA Kula VOLCANICS URANIUM Adsorption ISOTHERM
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Antimicrobial activities of three seaweeds extract against some human viral and bacterial pathogens
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作者 JELAN MOFEED MOHAMED DEYAB +3 位作者 ABDELNASER MOHAMED MAHMOUD MOUSTAFA SALLY NEGM EMAD EL-BILAWY 《BIOCELL》 SCIE 2022年第1期247-261,共15页
Microbial infections cause complicated health influences along with bad economic impacts.In the present investigation,three dominant seaweeds namely,Amphiroa anceps,Corallina officinalis and Sargassum filipendula were... Microbial infections cause complicated health influences along with bad economic impacts.In the present investigation,three dominant seaweeds namely,Amphiroa anceps,Corallina officinalis and Sargassum filipendula were collected from different Egyptian sites at the Red Sea and Mediterranean Sea during autumn 2019.Organic extracts of the three algae were screened for their antibacterial activity against three pathogenic bacteria Salmonella typhiimurium,Staphylococcus aureus and Escherichia coli,in addition to in vitro antiviral activity against Rotavirus(RV),and Coxsackie virus B3(CVB3)that cause severe diseases in human.Organic extract of A.anceps,C.officinalis and S.filipendula inhibit E.coli cells by 57.1%,85.7%,and 91.4%,respectively.The highest level of concentration of the C.officinalis extract(100μg/mL)inhibits 100%of Staphylococcus aureus cells followed by S.filipendula and A.anceps extract which inhibit 82.5%and 75%of S.aureus.Similarly,the highest concentration of C.officinalis extract inhibits S.typhiimurium by 80%.The extract of A.anceps exhibited a high antiviral effect against RV infection with TI=22 and virus titers lessened by 2.75 log TCID_(50) followed by extractions of C.officinalis with TI=18.3 and virus titers reduced by 2.5 log TCID_(50).Against CVB3 infection,the extract of A.anceps causes the highest antiviral activity with TI=15 and reduce the viral titers by 2.5 log TCID_(50),followed by extractions of C.officinalis with TI=8.8 and inhibition of virus titers by 1.75 log TCID_(50).Extract of S.filipendula displayed the lowest antiviral effects against RV and CVB3 infection with TI=2.4 and 1.4,respectively.The obtained results clarified that the extract of three marine seaweeds maintains a potent antimicrobial activity,making them a future promising source of new antimicrobial drugs. 展开更多
关键词 Seaweeds ANTIMICROBIAL ANTIBACTERIAL CYTOTOXICITY ANTIVIRAL
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Abugomry Induction Heater Design to Study the Thermal Properties of Magnetic Nanoparticles
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作者 Eltayeb Ibrahim Ahmed Elbeshir 《Journal of Physical Science and Application》 2016年第4期44-47,共4页
In this project a new simple induction heater design (Abugomry) operated at low power and low frequency 100w/100kHz was made. The thermal properties of three different MNPs (magnetic nano particles) were studied b... In this project a new simple induction heater design (Abugomry) operated at low power and low frequency 100w/100kHz was made. The thermal properties of three different MNPs (magnetic nano particles) were studied by Abugomry induction heater. The high temperatures of MNPs (47, 46 and 50) ℃, the heating rate (0.030, 0.025 and 0.028) ℃/min and the specific absorption rate (126, 115 and 105) W/g for the (α-Fe2O3, Fe3O4 and CoFe2O4) MNPs respectively, these results were suitable to use these MNPs in MHT (magnetic hyperthermia treatment). The results accrue from Abugomry of these MNPs that it's agree with the published results of the same MNPs, which were studied by induction heater operated at high/medium power and frequency. 展开更多
关键词 Induction heater thermal properties magnetic nanoparticles hyperthermia.
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Synthesis and Characterization of SnO<SUB>2</SUB>Flower-Shaped by Hydrothermal Route for Formaldehyde Sensing Properties
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作者 Abeer Alhadi Shuyi Ma +10 位作者 Shitu Pei Tingting Yang Pengdou Yun Qianqian Zhang Hamouda Adam Hamouda Li Wang Omer Almamoun Altayeb Alshiply Pengfei Cao Manahil H. Balal Khalid Ahmed Abbakar 《Advances in Materials Physics and Chemistry》 2021年第4期67-77,共11页
In this work, we’ve made SnO<sub>2</sub> flower formed with the aid of using easy test steps, and without cost, which is the hydrothermal approach and without a template. We have used a variety of techniq... In this work, we’ve made SnO<sub>2</sub> flower formed with the aid of using easy test steps, and without cost, which is the hydrothermal approach and without a template. We have used a variety of techniques to characterize SnO<sub>2</sub> flower-shaped by (SEM, TEM, XRD, BET and XPS) instruments. Confirmatory tests carried out have proven that the surface of the tetragonal structure of SnO<sub>2</sub> has a rough surface which makes it excellent for its gas-sensing properties. The gas detection test of SnO<sub>2</sub> flower-shaped proved that it possesses the selectivity of formaldehyde gas (about 30), the optimum operating temperature of the sensor is 220<span style="white-space:nowrap;"><span style="white-space:nowrap;">&#176;</span></span>C, and also the sensor has a high response time and recovery time is (5 s and 22 s) to 100 ppm, respectively. Particularly, the sensor has an obvious response value (2) when exposed to 5 ppm formaldehyde. As well, the mechanism of gas-sensing was also discussed. 展开更多
关键词 SnO2 Flower-Shaped Hydrothermal Method FORMALDEHYDE Semiconductor Gas Sensor
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Applying the New Extended Direct Algebraic Method to Solve the Equation of Obliquely Interacting Waves in Shallow Waters 被引量:1
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作者 KURT Ali TOZAR Ali TASBOZAN Orkun 《Journal of Ocean University of China》 SCIE CAS CSCD 2020年第4期772-780,共9页
In this study,the potential Kadomtsev-Petviashvili(pKP)equation,which describes the oblique interaction of surface waves in shallow waters,is solved by the new extended direct algebraic method.The results of the study... In this study,the potential Kadomtsev-Petviashvili(pKP)equation,which describes the oblique interaction of surface waves in shallow waters,is solved by the new extended direct algebraic method.The results of the study show that by applying the new direct algebraic method to the pKP equation,the behavior of the obliquely interacting surface waves in two dimensions can be analyzed.This article fairly clarifies the behaviors of surface waves in shallow waters.In the literature,several mathematical models have been developed in attempt to study these behaviors,with nonlinear mathematics being one of the most important steps;however,the investigations are still at a level that can be called‘baby steps’.Therefore,every study to be carried out in this context is of great importance.Thus,this study will serve as a reference to guide scientists working in this field. 展开更多
关键词 conformable fractional derivative new extended direct algebraic method interacting wave equation shallow water waves
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Effect of environmental factors on species diversity of the Yenice Hot Spot Forests in Turkey 被引量:1
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作者 Sevda Turkis Emire Elmas 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第6期1719-1730,共12页
We quantified the diversity of vascular plant species and described soil properties and topographical and climatic conditions of the Citdere and Kavakli Nature Reserves in the Yenice Forest of Turkey. We used the Shan... We quantified the diversity of vascular plant species and described soil properties and topographical and climatic conditions of the Citdere and Kavakli Nature Reserves in the Yenice Forest of Turkey. We used the Shannon-Weiner and Simpson's indices of diversity,Margalef's index of species richness and Pielou's evenness index to quantify the structure of vascular plant assemblages. We measured soil parameters(NO_3^-, NH_4^+,available P, Mg^(++), K^+, Na^+, Ca^(++), organic matter, pH,soil moisture), elevation, slope gradient and aspect and their correlations with plant community parameters. In total, we recorded and identified 207 species and subspecies in the study area. Species cover, richness and diversity indices varied significantly by vegetation type(P < 0.01). Available NO_3^- and Ca++ in the soil were important factors for the area and species representation in the species-environment correlations estimated for the Kavakli area. Available NO_3^-,pH, organic matter, Ca^(++) and K^+ in the soil were important factors for the area and species representation in the species-environment correlations analysed for the Citdere area. 展开更多
关键词 DIVERSITY Forest ecosystems Yenice hotspot Species richness
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Neutrosophic Soft Expert Sets 被引量:1
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作者 Mehmet Sahin Shawkat Alkhazaleh Vakkas Ulucay 《Applied Mathematics》 2015年第1期116-127,共12页
In this paper we introduce the concept of neutrosophic soft expert set (NSES). We also define its basic operations, namely complement, union, intersection, AND and OR, and study some of their properties. We give examp... In this paper we introduce the concept of neutrosophic soft expert set (NSES). We also define its basic operations, namely complement, union, intersection, AND and OR, and study some of their properties. We give examples for these concepts. We give an application of this concept in a decision-making problem. 展开更多
关键词 Soft Expert Set Neutrosophic Soft Set Neutrosophic Soft Expert Set
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Global investigation of the ionospheric irregularities during the severe geomagnetic storm on September 7-8, 2017
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作者 Ramazan Atıcı Selçuk Sagır 《Geodesy and Geodynamics》 2020年第3期211-221,共11页
In this study,the global effects of the severe geomagnetic storm on the Earth’s ionosphere on September5 e9,2017 with Coronal Mass Ejections(CMEs)associated with X-9.3 flares on September 6,2017 were investigated by ... In this study,the global effects of the severe geomagnetic storm on the Earth’s ionosphere on September5 e9,2017 with Coronal Mass Ejections(CMEs)associated with X-9.3 flares on September 6,2017 were investigated by the Rate of Total Electron Content(TEC)Index(ROTI).ROTI was used as a criterion of ionospheric irregularities that took place during the storm.This study was conducted with TEC values obtained from fifty stations connected to the International GNSS System(IGS)-GPS network for five different latitude regions.As a result,it was observed that the irregularities in the high latitude regions of the southern hemisphere were greater in number in comparison with those at the high latitude regions of the northern hemisphere during the storm.It was observed that these irregularities generally occurred during the main and recovery phases of the storm at all latitudes.The weak and moderate ionospheric irregularities that developed at high latitudes during the storm were more in the southern hemisphere.Especially,moderate ionospheric irregularities in high latitudes of both hemispheres took place in eastern longitudes(18 oE-160 oE).However,ionospheric irregularities in the mid-latitude regions were observed in more stations at the northern hemisphere than at the southern hemisphere.Generally,ionospheric irregularities during the storm developed at eastern longitudes in all sectors. 展开更多
关键词 Earth's ionosphere Geomagnetic storm Ionospheric irregularities ROTI
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On the Solutions of Difference Equation Systems with Padovan Numbers
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作者 Yasin Yazlik D. Turgut Tollu Necati Taskara 《Applied Mathematics》 2013年第12期15-20,共6页
In this study, we investigate the form of the solutions of the following rational difference equation systems? , , such that their solutions are associated with Padovan numbers.
关键词 RATIONAL DIFFERENCE EQUATION System Padovan NUMBERS PLASTIC Number
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Glycaspis brimblecombei Moore (Hemiptera: Aphalaridae), the New Exotic Pest of Eucalyptus in Northern Cyprus
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作者 Ismail Karaca Mustafa Avci Ozlem Guven 《Journal of Agricultural Science and Technology(A)》 2017年第8期552-556,共5页
Eucalypt-feeding psyllids, Glycaspis brimblecombei Moore (Hemiptera: Psylloidea: Aphalaridae), native to the Australian region, has emerged as an aggressive pest on Eucalyptus in many countries as it was described... Eucalypt-feeding psyllids, Glycaspis brimblecombei Moore (Hemiptera: Psylloidea: Aphalaridae), native to the Australian region, has emerged as an aggressive pest on Eucalyptus in many countries as it was described recently in Greece and Turkey. This study aimed to report this invasive species and its parasitoids on Eucalyptus growing area in Northern Cyprus. G. brimblecombei infested leaves were collected and brought to the laboratory for identification and collection of parasitoids emerged from the pest. In this paper, presence of G. brimblecombei and the parasitoid of the red gum lerp psyllid Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae) were reported for the first time in Northern Cyprus. Detailed information about the pest and its parasitoids were discussed. 展开更多
关键词 Glycaspis brimblecombei Northern Cyprus Psyllaephagus bliteus red gumlerp psyllid.
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Pure SnO<sub>2</sub>Gas Sensor with High Sensitivity and Selectivity towards C<sub>2</sub>H<sub>5</sub>OH
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作者 Abeer Alhadi Shuyi Ma +8 位作者 Tingting Yang Shitu Pei Pengdou Yun Khalid Ahmed Abbakar Qianqian Zhang Nina Ma Manahil H. Balal Hamouda Adam Hamouda Khalid Mohammed Adam 《Advances in Nanoparticles》 2021年第2期66-74,共9页
To observation, poisonous gases in the environment, Sensors with high selectivity, high response and low operating temperature are required. In this work, pure SnO<sub>2</sub> nanoparticles w<span>&l... To observation, poisonous gases in the environment, Sensors with high selectivity, high response and low operating temperature are required. In this work, pure SnO<sub>2</sub> nanoparticles w<span><span><span style="font-family:;" "="">as</span></span></span><span><span><span style="font-family:;" "=""> prepared by using a simple and inexpensive technique </span></span></span><span><span><span style="font-family:;" "="">(</span></span></span><span><span><span style="font-family:;" "="">hydrothermal method</span></span></span><span><span><span style="font-family:;" "="">)</span></span></span><span><span><span style="font-family:;" "=""> without a template. Various confirmatory tests were performed to characterize SnO<sub>2</sub> nanoparticles such as energy</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Scan<span>ning Electron Microscopy (SEM) and Transition Electron Microscopy</span> (TEM), during the detection of the gas, we found that p</span></span></span><span style="font-family:Verdana;"></span><span><span><span style="font-family:;" "="">ure SnO<sub>2</sub> nanoparticles ha</span></span></span><span><span><span style="font-family:;" "="">s</span></span></span><span><span><span style="font-family:;" "=""> a high selectivity for ethanol to 100 ppm at a low temperature (180</span></span></span><span><span><span style="font-family:;" "="">°C<span>) and a high response (about 27</span></span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">s) and a low detection limit of 5 ppm, also it<span style="color:red;"> </span>h</span></span></span><span><span><span style="font-family:;" "="">ave</span></span></span><span><span><span style="font-family:" color:red;"=""> </span></span></span><span><span><span style="font-family:;" "="">response/recovery times about (4</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">s, 2</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">s) respectively. The distinctive sensing properties of SnO<sub>2</sub> sensor make it a promising candidate for ethanol detection. Furthermore, the gas-sensing mechanism have been examined.</span></span></span> 展开更多
关键词 Hydrothermal Method Nanoparticles ETHANOL SnO2 Gas Sensor
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Effective Mass Model Reduced to Ordinary Mass Using Newton’s, Quantum and Generalized Special Relativity
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作者 Nagwa Idriss Ali Ahmed Mohamed Idriss Ahmed Mubarak Dirar Abd-Alla 《Natural Science》 2021年第9期398-406,共9页
The concept of the effective mass in crystals shows that the electron mass is affected by the crystal field and was experimentally verified. A useful expression for effective mass was obtained. Unfortunately this expr... The concept of the effective mass in crystals shows that the electron mass is affected by the crystal field and was experimentally verified. A useful expression for effective mass was obtained. Unfortunately this expression showed that the effective mass vanishes in the ab-sence of the external field. This is in conflict with observations which show that it reduces to the ordinary mass. To cure this defect a new model is developed assuming the existence of vacuum force as verified experimentally as shown by Casimir effect. Using Newton’s second law and the quantum expression of momentum, useful expressions were found. The same expression was found using generalized special relativity. Strikingly the three models reduced to the conventional one in the absence of vacuum, they also reduced to the ordinary electron mass in the absence of all forces. 展开更多
关键词 Effective Mass Newton’s Second Quantum Momentum Generalized Special Relativity
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On Period of Fibonacci Sequence in Finite Rings with Identity of Order P^2
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作者 Yasemin Tasvurdu Inci Gultekin 《Journal of Mathematics and System Science》 2013年第7期349-352,共4页
In this paper, we obtain the period of generalized Fibonacci sequence in finite rings with identity of order p2 by using equality recursively defined by Fn+2 = A1Fn+1 + A0Fn, for n ≥ 0, where F0 = 0 ( the zero of... In this paper, we obtain the period of generalized Fibonacci sequence in finite rings with identity of order p2 by using equality recursively defined by Fn+2 = A1Fn+1 + A0Fn, for n ≥ 0, where F0 = 0 ( the zero of the ring), F1 = 1 (the identity of the ring) and A0 , A1 are generators elements of finite rings with identity of order p2. Also, we get some results between the period of generalized Fibonacci sequence in the finite rings oforderp2 and characteristic of these rings. 展开更多
关键词 Fibonacci sequence PERIOD finite rings
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