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The assessment of time dependent flow of Williamson fluid with radiative blood flow against a wedge 被引量:1
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作者 K.Subbarayudu S.Suneetha P.Bala Anki Reddy 《Propulsion and Power Research》 SCIE 2020年第1期87-99,共13页
The present pagination reports both Brownian diffusion and thermophoresis aspects subject to magneto hydrodynamic Williamson fluid model.Assuming the flow is unsteady and blood is treated as Williamson fluid over a we... The present pagination reports both Brownian diffusion and thermophoresis aspects subject to magneto hydrodynamic Williamson fluid model.Assuming the flow is unsteady and blood is treated as Williamson fluid over a wedge with radiation.The governing equations are transformed into ordinary differential equations by using similarity variables.The analytical solutions of the transformed governing equations are obtained by using the RK 4th order method along with shooting technique solver.The effects of various physical parameters such as Hartmann number,local Weissenberg number,radiation parameter,unsteadiness parameter,Prandtl number,Lewis number,Brownian diffusion,thermophoresis,wedge angle parameter,moving wedge parameter,on velocity,temperature,concentration,skin friction,heat transfer rate and mass transfer rate have been discussed in detail.The velocity and temperature profile deprives for larger We and an opposite trend is observed for concentration.The radiation parameter is propositional to temperature and a counter behaviour is observed for Pr. 展开更多
关键词 The present pagination reports both Brownian diffusion and thermophoresis aspects subject to magneto hydrodynamic WILLIAMSON fluid model. Assuming the flow IS unsteady and blood IS treated as WILLIAMSON fluid over a WEDGE with radiation. The governing EQUATIONS are transformed into ordinary differential EQUATIONS by using similarity variables. The analytical solutions of the transformed governing EQUATIONS are obtained by using the RK 4th order method along with shooting technique solver. The effects of various physical parameters such as Hartmann NUMBER local Weissenberg NUMBER radiation PARAMETER unsteadiness PARAMETER Prandtl NUMBER Lewis NUMBER Brownian diffusion thermophoresis WEDGE angle PARAMETER moving WEDGE PARAMETER on velocity temperature concentration skin friction heat transfer rate and mass transfer rate have been discussed in detail. The velocity and temperature profile deprives for larger We and an opposite trend IS observed for concentration. The radiation PARAMETER IS propositional to temperature and a counter behaviour IS observed for Pr.
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Evaluation of berries of Phytolacca dodecandra for growth inhibition of Histoplasma capsulatum var.farciminosum and treatment of cases of epizootic lymphangitis in Ethiopia 被引量:2
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作者 Negesse Mekonnen Eyasu Makonnen +1 位作者 Nigatu Aklilu Gobena Ameni 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第7期505-510,共6页
Objective:To evaluate the berries of Phytolacca dodecundra(P.dodecandra) for its effect on Histoplasma cupsulatum var.farciminosum(HCF) and for the treatment of cases of epizootic lymphangitis(ELi.Methods:Samples were... Objective:To evaluate the berries of Phytolacca dodecundra(P.dodecandra) for its effect on Histoplasma cupsulatum var.farciminosum(HCF) and for the treatment of cases of epizootic lymphangitis(ELi.Methods:Samples were collected from un-ruptured nodules of cases of EL at Debre Zeit and Akaki(central Ethiopia).Mycologieal culture and isolation of HCF were performed at the Akliln Lemma Institute of Pathobiology.Phytochemical screening was done for n-butanol extract of P.dodecandra to delect alkaloids,saponins,phenolic compounds and flavonoids.The minimum inhibitory concentrations(MICs) and minimum fungicidal concentrations(MFCs) ol aqueous and n-butanol extracts of P.dodecandra against FICF were determined by agar dilution assay.For the in vivo trial.5%simple ointment was prepared from n-butanol extract and applied topically to 24(twelve early and twelve moderate) cases of F.L.Results:Phytochemical screening showed that n-butanol extract ol P.dodecandra was positive lor alkaloids.saponins and phenolic compounds but negative for flavonoids.The MFCs of n-butanol and aqueous extracts of P.dodecandra were(0.039%-0.078%) and(0.625%-1.250%),respectively.The MFCs of n-butanol and aqueous extracts of P.dodecandra were(0.078%t-0.156%)and(1.250%-2.500%),respectively.The MIC and MFC of ketoconazole(positive control) was(1.200×10^(-5)%-2.500×10^(-5)%) and(5.000× 10^(-5)%-1.000×10^(-4)%),respectively while growth was observed on free medium(negative control).From the total of 24 treated cases of EL,14(58.3%) responded lo treatment;however,10(41.7%) did not respond to treatment.There was no significant difference in the degree of response to treatment between early and moderate cases(χ~2=0.086:P=0.408.Conclusions:It can be concluded that n-butanol extract of P.dodecandra demonstrates antifungal effects while the aqueous extract shows no antifungal activity. 展开更多
关键词 EPIZOOTIC lymphangitis Phytolacca dodecandra HISTOPLASMA capsulatum var.farciminosum Minimum inhibitory concentration Minimum FUNGICIDAL concentration Phytochemical screening Antifungal activity Agar dilution assay Mycological culture In vivo trial Contagious DISEASE Chronic DISEASE Lymphangitis
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Retrieval of PM10 Concentration from an AOT Passive Remote-Sensing Station between 2003 and 2007 over Northern France
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作者 Houda Yahi Alain Weill +2 位作者 Michel Crepon Antoni Ung Sylvie Thiria 《Open Journal of Air Pollution》 2013年第4期63-75,共13页
A method of retrieving PM10 particles concentrations at the ground level from AOT (Aerosol Optical Thickness) measurements is presented. It uses data obtained among five years during 2003 to 2007 summers in the Lille ... A method of retrieving PM10 particles concentrations at the ground level from AOT (Aerosol Optical Thickness) measurements is presented. It uses data obtained among five years during 2003 to 2007 summers in the Lille region (northern France). As PM10 concentration strongly depends on meteorological variables, we clustered the meteorological situations provided by the MM5 meteorological model forced at the lateral boundaries by the operational NCEP model in eight classes (local weather types) for which a robust statistical relationship between AOT and PM10 was found. The meteorological situations were defined by the hourly vertical profiles of temperature and (zonal and meridian) wind components. The clustering of the weather types were obtained by a self-organizing map (SOM) followed by a hierarchical ascending classification (HAC). We were then able to retrieve the PM10 at the surface from the AERONET AOT measurements for each weather type by doing non linear regressions with dedicated SOMs. The method is general and could be extended to other regions. We analyzed the strong pollution event that occurred during August 2003 heat wave. Comparison of the results from our method with the output of the CHIMERE chemical-transport model showed the interest to tentatively combine these two pieces of information to improve particle pollution alert. 展开更多
关键词 Mass concentration (PM10) Aerosol Optical Thickness (Sun Photometer) COMPETITIVE Neural Network SELF-ORGANIZING Map (SOM) Weather Types
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Radon Concentration Measurements in Gattar Uranium Prospect, Northern Eastern Desert, Egypt
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作者 Naglaa Fahmi 《Journal of Analytical Sciences, Methods and Instrumentation》 2019年第1期1-11,共11页
The concentration of Radon in mines varies tremendously according to the country rock, type of mineralization and area. Ventilation is also an important factor. The absence of ventilation in mines tends to allow a hig... The concentration of Radon in mines varies tremendously according to the country rock, type of mineralization and area. Ventilation is also an important factor. The absence of ventilation in mines tends to allow a higher concentration of Radon to build up. This is very dangerous for the miners work inside. In this present work, the radon gas concentration is practically measured in closed uranium prospect mine located at Gabal (G.) Gattar. CR-39 solid state nuclear track detector technique is used. It is found that the radon concentration is around 80 kBq m-3 and an effective ventilation rates should be applied if there will be further works in the future. 展开更多
关键词 RADON in MINE Health Effect of RADON RADON Gas concentration Gabal Gattar Hurghada Solid State Nuclear Track Detector Applied Effective Ventilation
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Transport of Phenol in BS-12 Modified Lou Soil in the Column Experiment: Effect of Concentrations, pH and Ionic Strength
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作者 Sambath Yek Lingkai Zhang +4 位作者 Zhaofu Meng Soklun Heng Shuaibin Bu Haoyuan Lu Mengfei Zhang 《Journal of Water Resource and Protection》 2019年第5期540-553,共14页
Lou soil was modified by amphoteric surfactant in column experiment which was conducted. This study attempts to explore the transport of phenol to unmodified and modified soil and inquire into the effect of concentrat... Lou soil was modified by amphoteric surfactant in column experiment which was conducted. This study attempts to explore the transport of phenol to unmodified and modified soil and inquire into the effect of concentrations, pH, and ionic strength on phenol migration in the soil column. The parameters and breakthrough curves (BTCs) of transport were fitted by using the CXTFIT (version 2.1) model. The result of Cl?’s BTCs for non-reactive by determining the equilibrium model (EM) showed the retardation factor which was smaller than 1. The result of phenol’s BTCs by determining non-equilibrium model (NEM) was shown that the R-value increased while modification ratio increased, and the R was in order of CK (1.337) < 50BS-12 (4.085) < 100BS-12 (7.048). The lower to higher concentration of phenol didn’t affect to CK and 100BS-12 was able to block higher concentration. The effect of pH on transport to CK and 100BS-12 didn’t react and the average pore water velocity was decreased at pH = 4. The decreasing ionic strength of phenol migration on CK and 100BS-12 had effect and the average pore water velocity and retardation factor also decreased. The residual retention in soil was in order of CK < 50BS-12 < 100BS-12, and 100BS-12 could hold the amount of phenol than CK 7.21 times. Thus, amphoteric modified lou soil definitely blocks phenol migration and controls groundwater pollution. 展开更多
关键词 AMPHOTERIC MODIFIER (BS-12) MODIFIED Soil PHEnoL BTCs concentrationS PH Ionic Strength Residual Retention
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Study on the Concentration Inversion of NO &NO2 Gas from the Vehicle Exhaust Based on Weighted PLS
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作者 Kai Zhang Yujun Zhang +7 位作者 Kun You Yibing Lu Qixing Tang Ying He Guohua Liu Boqiang Fan Dongqi Yu Wenqing Liu 《Optics and Photonics Journal》 2017年第8期106-115,共10页
It becomes a key technology to measure the concentration of the vehicle exhaust components with the absorption spectra. But because of the overlap of gas absorption bands, how to separate the absorption information of... It becomes a key technology to measure the concentration of the vehicle exhaust components with the absorption spectra. But because of the overlap of gas absorption bands, how to separate the absorption information of each component gas from the mixed absorption spectra has become the key point to restrict the precision of the optical detection method. In this paper, the ex-perimental platform for the absorption spectrum of vehicle exhaust components has been established. Based on the ultraviolet absorption spectra measured with the platform of exhaust gas NO & NO2, the concentration regression model for the two components has been established with weighted partial least squares regression (WPLS). Finally the each spectral characteristic information of NO & NO2 gas has been separated and the concentration of each corresponding component has been reversed successfully. 展开更多
关键词 Absorption Spectra no & no2 GAS WEIGHTED Partial Least SQUARES Regression concentration INVERSION
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Photosynthetic Water Use Efficiency of Heritage and Modern Potatoes under Limited and Unlimited Water Environments
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作者 Isaac R. Fandika Peter D. Kemp +1 位作者 James P. Millner Dave Horne 《Agricultural Sciences》 2014年第14期1501-1512,共12页
Photosynthetic capacity for heritage (Taewa) and modern potato cultivars were compared at different water and nitrogenregimes in the glasshouse and field. The glasshouse was 2*2*4 factorial design with two irrigation:... Photosynthetic capacity for heritage (Taewa) and modern potato cultivars were compared at different water and nitrogenregimes in the glasshouse and field. The glasshouse was 2*2*4 factorial design with two irrigation: 100% ET and 60% ET;two applied N: 50 kg N ha-1 and 200 kg N ha-1, two Taewa (Moe Moe, Tutaekuri) and two modern potatoes (Moonlight, Agria). The 2009/2010 field experiment was a split-plot, with irrigation and rain-fed regimes as the main treatments: four potatoes above were sub-treatments. The 2010/2011 field experiment was a split-split-plot, with three water regimes as the main treatments: three cultivars (Moe Moe, Tutaekuri, and Agria) were subplots;two N rates were sub-sub-treatments. Gaseous exchange was measured by CIRAS-2 at different days from emergence. Leaf water potential was measured using pressure chamber method. Taewa achieved high photosynthetic WUE in glasshouse and 2010/2011 experiment by maintaining high An, low gs and low Ci compared to modern cultivars (p The An, gs and T increased with irrigation and N increase while decreasing Ci (p < 0.01). Water stress significantly increased VPD resulting in low An and photosynthetic WUE in Moonlight in the glasshouse. The leaf water potential for Taewa was very tolerant while modern potatoes were weakened by water stress. The study indicated that Taewa can be scheduled at partial irrigation without more detrimental effects on photosynthetic capacity while modern potatoes need full irrigation to avoid detrimental effects on photosynthetic capacity. 展开更多
关键词 Taewa Photosynthesis STOMATAL Conductance (gs) Transpiration (T) Irrigation Internal Carbon concentration (Ci) Vapour Pressure Deficit (VPD) Leaf WATER Potential and PHOTOSYNTHETIC WATER Use Efficiency (Photosynthetic WUE) SOLANUM TUBEROSUM SOLANUM andigena
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Effect of Non-Uniform Basic Concentration Gradient on the Onset of Double-Diffusive Convection in Micropolar Fluid 被引量:1
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作者 Subbarama Pranesh Arun Kumar Narayanappa 《Applied Mathematics》 2012年第5期417-424,共8页
The effect of non-uniform basic concentration gradient on the onset of double diffusive convection in a micropolar fluid layer heated and saluted from below and cooled from above has been studied. The linear stability... The effect of non-uniform basic concentration gradient on the onset of double diffusive convection in a micropolar fluid layer heated and saluted from below and cooled from above has been studied. The linear stability analysis is performed. The eigen value of the problem is obtained using Galerkian method. The eigen values are obtained for 1) free-free 2) rigid-free 3) rigid-rigid velocity boundary combination with isothermal temperature condition on spin-vanishing permeable boundaries. The influence of various micropolar parameters on the onset of convection has been analyzed. One linear and five non linear concentration profiles are considered and their comparative influence on onset is discussed and results are depicted graphically. It is observed that fluid layer with suspended particles heated and soluted from below is more stable compare to the classical fluid without suspended particles. 展开更多
关键词 Double Diffusive CONVECTION MICROPOLAR Fluid RAYLEIGH Benard CONVECTION and non UNIFORM concentration Gradients
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Individualized Design of the Ventilator Mask based on the Residual Concentration of CO2 被引量:4
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作者 Zhiguo Zhang Zhenxiao Li +2 位作者 Yifei Zhang Zhenze Wang Minzhou Luo 《Computer Modeling in Engineering & Sciences》 SCIE EI 2018年第11期157-167,共11页
OSAHS(Obstructive Sleep Apnea Hypopnea Syndrome)is a respiratory disease mainly characterized by limited and repeated pauses of breathing in sleep.Currently,the optimal treatment is to apply CPAP(Continuous Positive A... OSAHS(Obstructive Sleep Apnea Hypopnea Syndrome)is a respiratory disease mainly characterized by limited and repeated pauses of breathing in sleep.Currently,the optimal treatment is to apply CPAP(Continuous Positive Airway Pressure)ventilation on the upper airway of the patient through a household respiratory machine.However,if the ventilator mask is designed improperly,it might cause the residue and repeated inhalation of CO2,which will exert an adverse impact on the therapeutic effect.Present research numerically analyzed the CO2 transportation inside a commercial ventilator mask(Mirage SoftGel,ResMed,Australia)based on the reconstructed 3D numerical model of a volunteer's face and performed the improved design of the ventilator mask in terms of the CO2 residual concentration below the nostrils.The fluid dynamic analyses showed that at the end time of expiratory,the CO2 residual concentration below the nostrils is close to 4%.To improve the therapeutic effect,we changed the position of the exhaust holes and found that by moving the exhaust holes to the bottom of the ventilator mask,the CO2 residual concentration below the nostrils would be reduced to no more than 1%.This study established a near physiological computational model and provided a new method for the individualized design of the commercial ventilator mask. 展开更多
关键词 Obstructive sleep apnea HYPOPNEA syndrome continuous positive airway pressure VENTILATOR MASK CO2 RESIDUAL concentration 3D numerical reconstruction.
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Time Course of Elevations in Plasma Olprinone Concentration during Pediatric Cardiac Surgery
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作者 Satoshi Kurokawa Minoru Nomura 《Open Journal of Anesthesiology》 2013年第2期80-83,共4页
Purpose: Little research has been reported to date on the usefulness of olprinone in pediatric cardiac surgery, and no standard pediatric infusion protocol is currently established. Our study sought to confirm that th... Purpose: Little research has been reported to date on the usefulness of olprinone in pediatric cardiac surgery, and no standard pediatric infusion protocol is currently established. Our study sought to confirm that the regimen described herein rapidly achieves the requisite plasma olprinone concentrations. Methods: For the purposes of our study, we enrolled 13 patients: 7 biventricular repair candidates and 6 Fontan-type operation candidates. We administered a continuous infusion of olprinone to our study subjects at 0.3 μg/kg/min with no loading dose starting approximately 30 minutes (min) before weaning from cardiopulmonary bypass (CPB). We performed blood sampling at 15, 30, 45, 60, 90, and 120 min after the start of infusion and at the same elapsed intervals after separation from CPB. We measured plasma olprinone concentrations using ultra-fast liquid chromatography. Results: We observed effective plasma olpri-none concentrations (>20 ng/ml) at 30 min after weaning from CPB, or at 60 min after the start of infusion. Conclusion: We conclude that continuous olprinone infusion at 0.3 μg/kg/min without a loading dose initiated immediately after the release of aortic cross-clamping or immediately after the completion of all surgical procedures quickly and reliably achieves effective plasma concentrations. 展开更多
关键词 OLPRInoNE Phosphodiesterase-3 Inhibitor PLASMA concentration Pediatric Cardiac Surgery WEANING from Cardio-Pulmonary Bypass
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Equilibrium bed—concentration of nonuniform sediment 被引量:5
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作者 孙志林 孙志锋 DONAHUEJohn 《Journal of Zhejiang University Science》 EI CSCD 2003年第2期186-194,共9页
Knowledge of the equilibrium bed-concentration is vital to mathematic a l modeling of the river-bed deformation associated with suspended load but prev i ous investigations only dealt with the reference concentration ... Knowledge of the equilibrium bed-concentration is vital to mathematic a l modeling of the river-bed deformation associated with suspended load but prev i ous investigations only dealt with the reference concentration of uniform sedime nt because of difficulties in observation of the bed-concentration. This work i s a first attempt to develop a theoretical formula for the equilibrium bed-conce n tration of any fraction of nonuniform sediment defined at the bed-surface. The f ormula is based on a stochastic-mechanistic model for the exchange of nonunifor m sediment near the bed, and described as a function of incipient motion probabil ity, non-ceasing probability, pick-up probability, and the ratio of the averag e single-step continuous motion time to static time. Comparison of bed-concentra ti on calculated from the proposed formula with the measured data showed satisfacto ry agreement, indicating the present formula can be used for solving the differe ntial equation governing the motion of suspended load. 展开更多
关键词 Equilibrium bed concentration Suspended load Stoc hastic-mechanistic model nonuniform sediment.
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Is analysis of lower esophageal sphincter vector volumes of value in diagnosing gastroesophageal reflux disease? 被引量:3
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作者 Robert E.Marsh Christopher L.Perdue +4 位作者 Ziad T.Awad Patrice Watson Mohamed Selima Richard E.Davis Charles J.Filipi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2003年第1期174-178,共5页
AIM:With successful surgical treatment of gastroesophageal reflux disease(GERD),there is interest in understanding the anti-reflux barrier and its mechanisms of failure.To date, the potential use of vector volumes to ... AIM:With successful surgical treatment of gastroesophageal reflux disease(GERD),there is interest in understanding the anti-reflux barrier and its mechanisms of failure.To date, the potential use of vector volumes to predict the DeMeester score has not been adequately explored. METHODS:627 patients in the referral database received esophageal manometry and ambulatory 24-hour pH monitoring.Study data included LES resting pressure(LESP), overall LES length(OL)and abdominal length(AL),total vector volume(TVV)and intrabdominal vector volume(IVV). RESULTS:In cases where LESP,TVV or IVV were all below normal,there was an 81.4%probability of a positive DeMeester score.In cases where all three were normal, there was an 86.9%probability that the DeMeester score would be negative.Receiver-operating characteristics(ROC) for LESP,TVV and IVV were nearly identical and indicated no useful cut-off values.Logistic regression demonstrated that LESP and IVV had the strongest association with a positive DeMeester score;however,the regression formula was only 76.1%accurate. CONCLUSION:While the indices based on TVV,IVV and LESP are more sensitive and specific,respectively,than any single measurement,the measurement of vector volumes does not add significantly to the diagnosis of GERD. 展开更多
关键词 ADOLESCENT ADULT Aged Aged 80 and over CHILD Child Preschool Esophagogastric Junction Female Gastroesophageal Reflux Humans Hydrogen-Ion concentration Male MAnoMETRY Middle Aged ROC Curve Regression Analysis
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Novel application of PEG/SDS interaction as a wettability modifier of hydrophobic carbonate surfaces 被引量:1
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作者 Nasim Heydari Mahdi Asgari +1 位作者 Narjes Shojai Kaveh Zahra Fakhroueian 《Petroleum Science》 SCIE CAS CSCD 2019年第2期318-327,共10页
Wettability alteration of carbonate reservoirs from oil-wet to water-wet is an important method to increase the efficiency of oil recovery. Interaction between surfactants and polymers can enhance the effectiveness of... Wettability alteration of carbonate reservoirs from oil-wet to water-wet is an important method to increase the efficiency of oil recovery. Interaction between surfactants and polymers can enhance the effectiveness of surfactants in EOR applications. In this study, the interaction of polyethylene glycol(PEG) with an ionic surfactant, sodium dodecyl sulphate(SDS),is evaluated on an oil-wet carbonate rock surface by using contact angle measurements. The results reveal that wettability alteration of carbonate rocks is achieved through PEG/SDS interaction on the rock surface above a critical aggregation concentration(CAC). The behaviour of PEG/SDS aqueous solutions is evaluated using surface and interfacial tension measurements. Furthermore, the effect of PEG and SDS concentrations and impact of electrolyte addition on PEG/SDS interaction are investigated. It is shown that electrolyte(NaCl) can effectively decrease the CAC values and accordingly initiate the wettability alteration of rocks. Moreover, in a constant SDS concentration, the addition of NaCl leads to a reduction in the contact angle, which can also be obtained by increasing the aging time, temperature and pre-adsorption of PEG on the rock surface. 展开更多
关键词 Sodium dodecyl sulphate (SDS)- Polyethylene GLYCOL (PEG)- WETTABILITY alteration Contact angle Critical aggregation concentration CARBONATE surface
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A Resolution of the Black Hole Information Paradox via Transfinite Set Theory
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作者 Mohamed S. El Naschie 《World Journal of Condensed Matter Physics》 2015年第4期249-260,共12页
A black hole is essentially a relativistic as well as a quantum object. Therefore the information paradox of black holes is a consequence of the clash between these two most fundamental theories of modern physics. It ... A black hole is essentially a relativistic as well as a quantum object. Therefore the information paradox of black holes is a consequence of the clash between these two most fundamental theories of modern physics. It is logical to conclude that a resolution of the problem requires some form of a quantum gravity theory. The present work proposes such a resolution using set theory and pointless spacetime geometry. 展开更多
关键词 Information PARADOX Black HOLES S. Hawking G. 't Hooft L. Susskind Transfinite Set Theory noNCOMMUTATIVE Geometry Measure concentration Dvoretzkys Theorem DARK Energy CASIMIR Effect Nano CASIMIR Reactor
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The Relationship between Nigerian Bonnylight Crude Oil-Induced Hypoglycaemia and Endogenous Serum Insulin Concentration in Male Wistar Rats: The Role of Antioxidant Vitamins C and E
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作者 S. O. Ita E. O. Aluko +3 位作者 T. H. Olubobokun U. A. Okon A. B. Antai E. E. Osim 《American Journal of Molecular Biology》 2014年第2期81-88,共8页
The relationship between Nigerian Bonny Light crude oil (NBLCO) induced hypoglycaemia and endogenous serum insulin concentration;the role of antioxidant vitamin C or E supplementation was the focus of this study. Fort... The relationship between Nigerian Bonny Light crude oil (NBLCO) induced hypoglycaemia and endogenous serum insulin concentration;the role of antioxidant vitamin C or E supplementation was the focus of this study. Forty adult male Wistar rats were randomly divided into group I, which served as the control, group II, which was oral gavaged 6 ml/kg of NBLCO, groups III and IV, which were in addition to 6 ml/kg of NBLCO supplemented with 9 ml/kg and 1 mg/kg of vitamin E or C, respectively for 28 days. Results showed that NBLCO significantly (p < 0.05) lower body weight and food intake compared with control. These effects exerted by NBLCO were however significantly (p < 0.05) reversed by vitamin E or C supplementation. The NBLCO significantly (p < 0.05) reduced fasting blood glucose (FBG) when compared with control, the antioxidant vitamins supplementation significantly (p < 0.05) reversed the crude oil effect. The mean serum insulin level in NBLCO, vitamin E or C supplemented groups is not significantly different from the control. There was no significant correlation between FBG and fasting serum insulin concentrations in all the groups on day 28. It has been demonstrated in this study that direct oral ingestion of crude oil (NBLCO) could reduce food intake, body weight and cause hypoglycemia;the hypoglycemia may not be a function of serum insulin concentration. Interestingly, the hazardous effects of NBLCO could be ameliorated with antioxidant vitamin C or E supplementation. 展开更多
关键词 NIGERIAN Bonny Light CRUDE Oil HYPOGLYCAEMIA Serum Insulin concentration ANTIOXIDANT VITAMINS
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Spatial Variations in Particle Size,Heavy Mineral Assemblage and Magnetic Concentration of Dark-reddish Sands on Cedar Beach,Western Lake Erie,Ontario,Canada
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作者 Maria T.Cioppa 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期124-124,共1页
Environmental magnetic research on beaches and shoreline processes is limited.Therefore,we carried out environmental magnetic studies on the heavy mineral-enriched,dark-reddish sands on Cedar Beach of western Lake Eri... Environmental magnetic research on beaches and shoreline processes is limited.Therefore,we carried out environmental magnetic studies on the heavy mineral-enriched,dark-reddish sands on Cedar Beach of western Lake Erie(41.68°N,82.40°W).Magnetite has been identified as the dominant magnetic mineral of these sands.This study reveals a spatial variation in concentration of magnetite particles,distribution of 展开更多
关键词 heavy mineral MAGNETIC concentration grain size dark-reddish SANDS cross-shore and lonshore variation Cedar BEACH Lake Erie
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Prospectivity modeling of porphyry copper deposits: recognition of efficient mono-and multi-element geochemical signatures in the Varzaghan district, NW Iran 被引量:1
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作者 Reza Ghezelbash Abbas Maghsoudi Mehrdad Daviran 《Acta Geochimica》 EI CAS CSCD 2019年第1期131-144,共14页
The Varzaghan district at the northwestern margin of the Urumieh–Dokhtar magmatic arc, is considered a promising area for the exploration of porphyry Cu deposits in Iran. In this study we identified mono-and multi-el... The Varzaghan district at the northwestern margin of the Urumieh–Dokhtar magmatic arc, is considered a promising area for the exploration of porphyry Cu deposits in Iran. In this study we identified mono-and multi-element geochemical anomalies associated with Cu–Au–Mo–Bi mineralization in the central parts of the Varzaghan district by applying the concentration–area fractal method. After mono-element geochemical investigations, principal component analysis was applied to ten selected elements in order to acquire a multi-element geochemical signature based on the mineralization-related component. Quantitative comparisons of the obtained fractal-based populations were carried out in accordance with known Cu occurrences using Student's t-values. Then,significant mono-and multi-element geochemical layers were separately combined with related geologic and structural layers to generate prospectivity models, using the fuzzy GAMMA approach. For quantitative evaluation of the effectiveness of different geochemical signatures in final prospectivity models, a prediction-area plot was adapted. The results show that the multi-element geochemical signature of principal component one(PC1) is more effective than mono-element layers in delimiting exploration targets related to porphyry Cu deposits. 展开更多
关键词 GEOCHEMICAL signature concentration–area(C–A) fractal Principal component analysis(PCA) Students t-value Fuzzy mineral prospectivity modeling(MPM) Predictionarea(PA) PLOT
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Geophysical criterion of pre-outburst coal outsqueezing from the face space into the working 被引量:1
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作者 Alexander Shadrin Yuliya Diyuk 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第3期499-506,共8页
The initial process of coal and gas sudden outburst is studied in the article when under the influence of rock and gas pressure the part of a coal seam layer(a coal section)is squeezed out from the mouth of the future... The initial process of coal and gas sudden outburst is studied in the article when under the influence of rock and gas pressure the part of a coal seam layer(a coal section)is squeezed out from the mouth of the future outburst cavity in a jump-like manner into the working.Geo-mechanical criterion for a part of a coal seam layer outsqueezing in the form of the relation of active(squeezing out)and passive(preventing the outsqueezing)forces is defined in the article.Based on it,the geophysical criterion is defined by expressing basic physical parameters through geo-physical ones:the current stress is defined by spectral-acoustic method through the ratio of high frequency and low-frequency components of an acoustic signal,which is generated into a face working space by the mining equipment operating in the face;in-situ gas pressure is defined by gas analytical method by the concentration of methane in the atmosphere of the working;the strength of the most broken coal layer is defined by a strength measuring device(a device for measuring the depth of a steal cone punched into the coal by a spring mechanism).This paper studies the influence of acoustic,strength and filtrating and collecting properties of a face working space on the limit value of an obtained geophysical criterion of pre-outburst squeezing of a coal‘‘plug”out of the mouth of the future outburst cavity into the working. 展开更多
关键词 Block-like structure CRITERION of a COAL section outsqueezing Spectral-acoustic method Stress condition COAL strength property In-situ GAS pressure Aero and GAS control equipment METHANE concentration
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Challenging the Expiry Dates of Two Mycotoxins Standards: Afla and Ochra A
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作者 A. Aridi L. Baydoun C. M. S. T. Sukhn 《Journal of Materials Science and Chemical Engineering》 2017年第8期59-68,共10页
Objectives: To challenge the expiry dates of low concentration high purity mycotoxins standards. Literature Review: Aflatoxins (AFs) and Ochratoxin A (OTA) are persistent mycotoxins with adverse effects on humans. Myc... Objectives: To challenge the expiry dates of low concentration high purity mycotoxins standards. Literature Review: Aflatoxins (AFs) and Ochratoxin A (OTA) are persistent mycotoxins with adverse effects on humans. Mycotoxins standards are purchased to determine mycotoxin concentrations in food and may be stocked in some laboratories beyond expiry dates causing laboratories financial losses. Methods: Certified mycotoxins standards were purchased over the years from the same supplier at times and at other times from two different suppliers for quality control purposes. For AFs, six chromatographic runs for each of the mycotoxins standards were done to compare the difference among these standards having the following expiry dates (2008, 2012, 2013 and 2018). AFs standards purchased/obtained from two different suppliers in 2016 and expiring in 2018 were also compared. For OTA, the difference of concentration obtained between two years (2010 and 2018) was tested. All samples were run on a HPLC equipped with a fluorescence detector. Linearity of calibration curves and the points of lowest detection were determined for AFs components and for OTA from the unexpired mycotoxins standards. Results: At a 0.05 significance level and using non parametric tests, the statistical test revealed a p of 0.166, 0.153, 0.358 and 0.03 for B1, G1, B2 and G2 respectively among years for standards from same supplier and 0.037, 0.109, 0.182 and 0.182 for B1, G1, B2 and G2 respectively for unexpired standards from two different suppliers. For OTA, a p of 0.109 was obtained for standards of different expiry dates purchased from different suppliers. Conclusion: High purity low concentration mycotoxin standards purchased a decade ago (i.e. expired) did not differ from those purchased this current year (still valid). Hence, the expiry date can be renewed reducing the laboratories expenses. Manufacturers are urged to reconsider the expiry dates. 展开更多
关键词 Mycotoxins AFLATOXINS OCHRATOXIN A G1 G2 B1 B2 OTA Persistent Ther-mostable STANDARDS Certified Low concentration High PURITY Challenge Expiry Date Years HPLC MANUFACTURER SUPPLIERS
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Assessment of duodenogastric reflux by combined continuous intragastric pH and bilirubin monitoring 被引量:30
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作者 Fei Dai Jun Gong Ru Zhang Jin-Yan Luo You-Ling Zhu Xue-Qin Wang,Department of Gastroenterology,Second Hospital of Xi’ an Jiaotong University,Xi’an 710004,Shaanxi Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第2期382-384,共3页
AIM: To assess the diagnostic value of a combination of continuous intragastric pH and bilirubin monitoring in the detection of duodenogastric reflux (DGR), and the effects of diet on the bilirubin absorbance. METHODS... AIM: To assess the diagnostic value of a combination of continuous intragastric pH and bilirubin monitoring in the detection of duodenogastric reflux (DGR), and the effects of diet on the bilirubin absorbance. METHODS: 30 healthy volunteers were divided into two groups: standard diet group (Group 1) 18 cases, free diet group (Group 2)12 cases. Each subjects were subjected to simultaneous 24-hour intragastric pH and spectrophotometric bilirubin concentration monitoring (Bilitec 2000). RESULTS: There was no difference of preprandial phase bilirubin absorbance between two groups. The absorbance of postprandial phase was significantly increased in group 2 than group 1. There was no difference between preprandial phase and postprandial phase absorbance in group 1. Postprandial phase absorbance was significantly higher in group 2. In a comparison of bile reflux with intragastric pH during night time, there were 4 types of reflux: Simultaneous increase in absorbance and pH in only 19.6%, increase in bilirubin with unchanged pH 33.3%, pH increase with unchanged absorbance 36.3%, and both unchanged in 10.8%. Linear regression analysis showed no correlation between percentage total time of pH【4 and percentage total time of absorbance】0.14, r=0.068 P【0.05. CONCLUSION: Because of the dietary effect, high absorbance fluids or foods should be avoided in detection. Intragastric pH and bilirubin monitoring separately predict the presence of duodenal (and/or pancreatic) reflux and bile reflux. They can not substitute for each other. The detection of DGR is improved if the two parameters are combined simultaneously. 展开更多
关键词 ADULT Aged BILIRUBIN DIET Duodenogastric Reflux FEMALE Fiber Optics Humans Hydrogen-Ion concentration Male Middle Aged Postprandial Period Random Allocation Research Support non-U.S. Gov't
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