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A novel indicator system for catalytic spectrophotometric determination and speciation of inorganic selenium species (Se(Ⅳ), Se(Ⅵ)) at trace levels in natural lake and river water samples

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Rare Metals 2011年第5期30卷 477-487页

作者： Ramazan Gürkan Halil brahim Ulusoy Mehmet akay Pinar Bulut Department of Chemistry Faculty of Science University of Cumhuriyet

A novel catalytic kinetic method is proposed for the determination of Se（Ⅳ）, Se（Ⅵ）, and total inorganic selenium in water based on the catalytic effect of Se（Ⅳ） on the reduction of Celestine blue by sodium sulfide at pH 7.0 phosphate buffer. The fixed-time method was adopted for the determination and speciation of inorganic selenium. Under the optimum conditions, the two calibration graphs are linear with a good correlation coefficient in the range 2-20 and 20-200 μg·L-1 of Se（Ⅳ） for the fixed-time method at 30℃. The experimental and theo- retical detection limits of the developed kinetic method were found to be 0.21 and 2.50 μg·L-1 for the fixed-time method （3 min）. All of the variables that affect the sensitivity at 645 nm were investigated, and the optimum conditions were established. The interference effect of various cations and anions on the Se（Ⅳ） determination was also studied. The selectivity of the selenium determination was greatly improved with the use of the strongly cation exchange resin such as Amberlite IR120 plus as long as chelating agents of thiourea and thiosulphate. The proposed kinetic method was validated statistically and through recovery studies in natural water samples. The relative standard deviations （RSDs） for ten replicate measurements of 2, 10, and 20 μg·L-1 of Se（Ⅳ） change between 0.35% and 5.58%, while the RSDs for ten replicate measurements of 3, 6, and 12 μg·L-1 of Se（Ⅵ） change between 0.49% and 1.61%. Analyses of a certified standard reference material （NIST SRM 1643e） for selenium using the fixed-time method showed that the proposed kinetic method has good accuracy. The Se（Ⅳ）, Se（Ⅵ）, and total inorganic selenium in lake and river water samples have been successfully determined by this method after selective reduction of Se（Ⅵ） to Se（Ⅳ）.

关键词： selenium speciation Celestine blue catalytic effect kinetic spectrophotometry natural waters

Winner-takes-all decision-making in Fruit Fly Drosophila

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Winner-takes-all decision-making in Fruit Fly Drosophila

Airborne Pollen Grains of Burdur, Turkey

中国神经科学学会第十二届全国学术会议

作者： ak Guo Ke Zhang Haifeng SU Institute of Neuroscience State Key Laboratory of Neuroscience CAS Center for Excellence in Brain Science and Intelligence TechnologyShanghai Institutes for Biological Sciences Chinese Academy of Sciences Institute of Biophysics State Key Laboratory of Brain and Cognitive Science Chinese Academy of Sciences

"Nothing in neurobiology makes sense except in the light of behaviour"（***, 1994）. "Action selection is the main task of the brain"（***,2013）. How can we generate the right behavior at the right moment and the right place? Decision making is essential for the behaviorselection. We have designeda ‘color/position’ dilemma in the visual flight simulator to study the value–based decision-makingin Drosophila. Individual flies were conditioned to choose a flight path in accordance with the color（green and blue） and position（upper and lower） cues and then confronted with choice test with color and position cues reversed after *** results revealed that wild-type flies are able to resolve this paradoxical situation by evaluating the ‘relative value’ of the current information and making a nonlinear ‘winner-takes-all’ *** decision curve exhibited a clear-cut and sigmoid-like function（Tang and Guo, 2001）. We found that flies with defective dopamine system or MBs（mushroom bodies, a part of fly’s central brain, as a centerof free will or intelligent control） functionhave trouble in deciding between the two conflicting visual features（Zhang et al,2007）.Lastly we have found thata pair of APLneuron（the anterior paired lateral GABAergic inhibitory neuron）（Liu and Davis,2009）, which densely innervate the MB, is also involved in the salience-based decision-making that genetic silencing of APL neurons turns the nonlinear choice behavior into linear one（Su et al., in preparation）. This effect was mediated by ionotropic GABAA receptors, RDL, which is highly expressed in all lobes of the MB（Liu et al., 2009）.Together, we suggest a Gain-Gating Mechanism of decision making that during decision making process the one option（"winner"）will be inflated by the Dopamine Gain Mechanism, while the alternative one（"loser"） will be rejected by GABA Inhibition Gating resulting in "Winner takes all".We believe that our Gain-Gating framework may provide a template for

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Acta Botanica Sinica 2000年第8期42卷 864-867页

作者： Adem BIC Ahmet ak Depsrtment of Biology Faculty

The pollen grains in the atmosphere of Burdur have been studied for a two_year period (1996 through 1997) with a Durham sampler. A total of 11?881 pollen grains belonging to 39 taxa have been identified and recorded with some unidentified ones. Of them, 5?726 were identified in 1996 and 6?155 in 1997. Of the total pollen grains, 76.51% were arboreal, 21.62% non_arboreal and 1.87% unidentified. The majority of the investigated pollen grains were from Pinus L., Cupressaceae, Gramineae, Quercus L., Platanus L., Chenopodiaceae/Amaranthaceae, Salix L., Cedrus L., Compositae, Juglans L. and Urticaceae respectively. The highest level of pollen concentration was in May.

关键词：土耳其空气花粉浓度花粉过敏周变化月变化

Approximate solutions of Schrdinger equation for Eckart potential with centrifugal term

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Chinese Physics B 2010年第9期19卷 155-160页

作者： F. Taskin G. Koak Department of Physics Erciyes University

The approximate analytical solutions of the Schrodinger equation for the Eckart potential are presented for the arbitrary angular momentum by using a new approximation of the centrifugal term. The energy eigenvalues and the corresponding wavefunctions are obtained for different values of screening parameter. The numerical examples are presented and the results are in good agreement with the values in the literature. Three special cases, i.e., s-wave, ξ= λ=1, and β=0, are investigated.

关键词： Schrodinger equation Eckart potential bound state

Protein adsorption, cell viability and corrosion properties of Ti6Al4V alloy treated by plasma oxidation and anodic oxidation

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International Journal of Minerals,Metallurgy and Materials 2020年第9期27卷 1269-1280页

作者： ÖzgüBayrak Hojjat Ghahramanzadeh Asl Ayşe ak Department of Mechanical Engineering Erzincan Binali Yıldırım UniversityErzincan 24100Turkey Department of Mechanical Engineering Karadeniz Technical UniversityTrabzon 61080Turkey Vocational School of Health Services Medical Imaging Techniques ProgrammeKocaeli UniversityKocaeli 41001Turkey

The hardness,wettability,and electrochemical properties of Ti6Al4V alloy surfaces treated with anodic oxidation and plasma oxidation as well as the viabilities of the different cell lines on the obtained surfaces were *** anodic oxidation was performed for 10 min under 100 V potential,and it resulted in a 0.95μm thick nanoporous anatase-TiO2 *** the other hand,plasma oxidation was carried out at 650℃ for 1 h and resulted in a dense rutile-TiO2 structure with a thickness of 1.2μ*** a hardness of HV0.025823 and roughness of^220 nm were obtained by plasma oxidation,those obtained by anodic oxidation were HV0.025512 and^130 nm,*** anodic oxidation process created a more hydrophilic surface with a contact angle of 87.2°.Both oxidation processes produced similar properties in terms of corrosion behavior and showed better resistance than the as-received state in a certain range of ***,the surface treatments led to no significant change in the protein adsorption levels,which indicates that the difference in viability between the osteoblast and fibroblast cells was not due to the difference in surface protein *** all the factors,the surfaces obtained by anodic oxidation treatment revealed higher cell viability than those obtained by plasma oxidation(p=0.05).

关键词： Ti6Al4V oxidation corrosion cell viability protein adsorption

A neural network based methodology to predict site-specific spectral acceleration values

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Earthquake Engineering and Engineering Vibration 2010年第4期9卷 459-472页

作者： Kamatchi P Rajasankar J Ramana GV Nagpal ak CSIR-Structural Engineering Research Centre CSIR Campus Dept. Civil. Eng. IIT Delhi New Delhi 110 016 India

A general neural network based methodology that has the potential to replace the computationally-intensive site-specific seismic analysis of structures is proposed in this paper. The basic framework of the methodology consists of a feed forward back propagation neural network algorithm with one hidden layer to represent the seismic potential of a region and soil amplification effects. The methodology is implemented and verified with parameters corresponding to Delhi city in India. For this purpose, strong ground motions are generated at bedrock level for a chosen site in Delhi due to earthquakes considered to originate from the central seismic gap of the Himalayan belt using necessary geological as well as geotechnical data. Surface level ground motions and corresponding site-specific response spectra are obtained by using a one-dimensional equivalent linear wave propagation model. Spectral acceleration values are considered as a target parameter to verify the performance of the methodology. Numerical studies carried out to validate the proposed methodology show that the errors in predicted spectral acceleration values are within acceptable limits for design purposes. The methodology is general in the sense that it can be applied to other seismically vulnerable regions and also can be updated by including more parameters depending on the state-of-the-art in the subject.

关键词： neural network response spectra local soil conditions amplification factor

GAJA:3D CAD methodology for developing a parametric system for the automatic(re)modeling of the cutting components of compound washer dies

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第5期14卷 327-340页

作者： David POTONIK Bojan DOLak Miran ULBIN Emo-orodjarna d.o.o. Bezigrajska 10SI-3000CeljeSlovenia Faculty of Mechanical Engineering University of MariborSmetanova 17SI-2000MariborSlovenia

For the designing of cutting-dies is a complex and experience-based process,it is poorly supported by conventional 3D CAD ***,the majority of design activities,including the(re)modeling of those cutting die-components that are directly responsible for performing shaping operations on a sheet-metal stamping part,traditionally still need to be carried-out repetitively,separately,and manually by the *** eliminate some of these drawbacks and upgrade the capabilities of conventional 3D CAD software,this paper proposes a new methodology for the development of a parametric system capable of automatically performing a(re)modeling process of compound washer dies' *** presented methodology integrates CATIA V5 built-in modules,including Part Design,Assembly Design and Knowledge Advisor,publication mechanism,and compound cutting die-design *** system developed by this methodology represents an 'intelligent' assembly template composed of two modules GAJA1 and GAJA2,***1 is responsible for the direct input of the die-design problem regarding the shape,dimensions and material of the stamping part,its extraction in the form of geometric features,and the transferring of relevant design parameters and features to the module ***2 interprets the current values for the input parameters and automatically performs the modeling process of cutting die-components,using die-design knowledge and the company's internal design and manufacturing *** results show that this system significantly shortens the modeling-time for cutting the die-components,improves the modeling-quality,and enables the training of inexperienced designers.

关键词： Parametric modeling Cutting dies Computer-aided systems Knowledge-based design

Effect of common salt on laboratory reared immature stages of Aedes aegypti(L)

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Asian Pacific Journal of Tropical Medicine 2010年第3期3卷 173-175页

作者： Mukhopadhyay ak Tamizharasu W Satya Babu P Goutam Chandra Hati ak National Institute of Communicable Diseases Regional Filaria Training & Research Center Department of Zoology The University of Burdwan School of Tropical Medicine

Objective:To observe the effect of common salt(NaCl) on immature stages of laboratory reared Aedes aegypti(L).Methods:A laboratory colony of Aedes aegypti mosquitoes of Rajahmundry strain was established in the laboratory of National Institute for Communicable Disease(NICD), Rajahmundry unit at(26±2)℃with relative humidity of(70±10)%.1.00%,1.25%and 1.50% solutions of common salt(NaCl) were selected to observe the susceptibility status of immature stages of Aedes aegypti in ***:Fifty percent larvae of Aedes aegypti died within 19,31 and 48 hours when exposed to 1.50%,1.25%and 1.00%common salt solution, *** percent of the larvae died within 29,57 and 108 hours when exposed to the same salt solutions,*** high pupal mortality was observed varying from 81.8% to 40.0%.Formation of pupae was found inversely proportional in the presence of concentration of common salt in breeding ***:With easy availability,less toxicity and long lasting nature,common salt may be applied in unused containers,especially in junkyards where surveillance mechanism is poor along with other conventional vector control methods in order to control breeding of Aedes aegypti,the vector of dengue/ dengue hemorrhagic fever and chikungunya.

关键词： Common salt Immature stages Aedes aegypti(L) Control

An Investigation on the Formation of Submerged Bar Under Surges in Sandy Coastal Region

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China Ocean Engineering 2012年第3期26卷 535-546页

作者： Mustafa DEMIRCI M.Sami akZ Civil Engineering Department Engineering FacultyMustafa Kemal UniversityskenderunHatay 31040Turkey Civil Engineering Department Engineering and Architecture Facultyukurova UniversityAdana 01100Turkey

Cross-shore sediment transport rate exposed to waves is very important for coastal morphology, the design of marine structures such as seawalls, jetties, breakwaters etc, and the prevention of coastal erosion and accretion due to onoff shore sediment transportation. In the present study, the experiments on cross-shore sediment transport are carried out in a laboratory wave channel with initial beach slopes of 1/8, 1/10 and 1/15. By using the regular waves with different deep-water wave steepnesses generated by a pedal-type wave generator, the geometrical characteristics of beach profiles under storm conditions and the parameters affecting on-off shore sediment transport are investigated for the beach materials with medium diameters of d50=0.25, 0.32, 0.45, 0.62 and 0.80 mm. The offshore bar geometric characteristics are the horizontal distances from the shoreline to the bar beginning （Xb）, crest （Xt）, and ending （Xs） points, the depth from the bar crest to the still water level （ht）, and the bar volume （Vbar）. The experimental results have indicated that when the deep-water steepness （Ha/L0） increased, the net movement to seaside increased. With the increasing wave steepness, the bars moved to widen herewith the vertical distances from still water level to the bar beginning （Xb）, crest （Xt） and ending （Xs） points and the horizontal distances from the coast line to the bar beginning, crest and ending points increased. It was also shown from experimental results that the horizontal distances from the bar beginning and ending points to the coast line increased with the decrease of the beach slope. The experimental results obtained from this study are compared with previous experimental work and found to be of the same magnitude as the experimental measurements and followed the expected basic trend.

关键词： cross-shore sediment transport beach profiles bar parameters experimental study