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Electrocatalytic Oxidation of Calcium Folinate on Carboxyl Graphene Modified CuxO/Cu Electrode 被引量:2
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作者 Li-wen Wang Shou-guo Wu +2 位作者 Tian-yang Shi Wei Wei Pan Pan 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第6期729-734,I0002,共7页
Carboxyl graphene modified CuxO/Cu electrode was fabricated. The bare copper electrode was firstly anodic polarized in 1.0 mol/L NaOH solution in order to get CuxO nanoparticles, then the carboxyl graphene (CG) was ... Carboxyl graphene modified CuxO/Cu electrode was fabricated. The bare copper electrode was firstly anodic polarized in 1.0 mol/L NaOH solution in order to get CuxO nanoparticles, then the carboxyl graphene (CG) was electrodeposited on the CuxO/Cu electrode by cyclic potential sweeping. The electrocatalytic oxidation behaviors of calcium folinate (CF) at the graphene modified CuxO/Cu electrode were investigated by cyclic voltammetry. A positive scan polarization reverse catalytic voltammetry was used to obtain the pure catalytic oxidation current. The graphene modified CuxO/Cu electrode was served as the electrochemical sensor of CF, a highly sensitivity of 22.0μA.(μmol/μL)^-1cm^-2 was achieved, and the current response was linear with increasing CF concentration in the range of 2.0×10^-7 mol/L to 2.0×10^-5 mol/L, which crossed three orders of magnitude, and the detection limit was found 7.6×10^-5 mol/L (S/N=3). In addition, the proposed sensor was successfully applied in determination of CF in drug sample. 展开更多
关键词 Calcium folinate Carboxyl graphene CuxO/Cu electrode Chemically modi-fied electrode Positive scan polarization reverse catalytic voltammetry
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IGS polar motion measurement accuracy 被引量:2
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作者 Jim Ray Paul Rebischung Jake Griffiths 《Geodesy and Geodynamics》 2017年第6期413-420,共8页
We elaborate an error budget for the long-term accuracy of IGS(International Global Navigation Satellite System Service) polar motion estimates, concluding that it is probably about 25-30 μas(1-sigma)overall, alt... We elaborate an error budget for the long-term accuracy of IGS(International Global Navigation Satellite System Service) polar motion estimates, concluding that it is probably about 25-30 μas(1-sigma)overall, although it is not possible to quantify possible contributions(mainly annual) that might transfer directly from aliases of subdaily rotational tide errors. The leading sources are biases arising from the need to align daily, observed terrestrial frames, within which the pole coordinates are expressed and which are continuously deforming, to the secular, linear international reference frame. Such biases are largest over spans longer than about a year. Thanks to the very large number of IGS tracking stations, the formal covariance errors are much smaller,around 5 to 10 μas. Large networks also permit the systematic frame-related errors to be more effectively minimized but not eliminated. A number of periodic errors probably also influence polar motion results, mainly at annual, GPS(Global Positioning System) draconitic, and fortnightly periods, but their impact on the overall error budget is unlikely to be significant except possibly for annual tidal aliases. Nevertheless, caution should be exercised in interpreting geophysical excitations near any of the suspect periods. 展开更多
关键词 PM(Polar motion) GPS(Global positioning System) EOPs(Earth orientation parameters) Accuracy IGS(International GNSS Service)
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An Opinion Mining Task in Turkish Language: A Model for Assigning Opinions in Turkish Blogs to the Polarities
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作者 Cigdem Aytekin 《Journalism and Mass Communication》 2013年第3期179-198,共20页
Global changes took place at a neck-breaking speed in lots of fields along with the Web 2.0 era, which can be stated as the new Internet trend. Web pages which once were a statical structure that can be said to become... Global changes took place at a neck-breaking speed in lots of fields along with the Web 2.0 era, which can be stated as the new Internet trend. Web pages which once were a statical structure that can be said to become dynamic pages created by users, and in this regard they can be said to have been democratized by evolving. Social media, which were structured alongside with this era, by providing a large data flow for businesses, present new and improvable opportunities in the field of creating effective strategies. There are lots of blogs in today's Internet environment which includes customer ideas regarding the products/services that they possess. This environment, which in a way globalizes the customer ideas, is a new medium suitable for examination in terms of its increasing the business-customer interaction and due to its transporter nature; it provides the text data that may be analyzed in the field of Customer Relationship Management to businesses. Thus, businesses should follow blog environments to see how the product/service they provide is greeted in terms of the customer focus and it should be seen as an important job on which they can conduct effective analyses. For this purpose, a model proposal that will assign the ideas to the Turkish blogs was given in the study. Opinion mining methods were used in the model, and so to perceive a general look-on about products/services, a methodology was devised, which will assign the text based opinion data on the Turkish blogs to the poles. Success of the pole assignment of the model is evaluated with the precision measure. 展开更多
关键词 opinion mining text classification sentiment classification semantic orientation positive/negative polarity
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