Surface Modification of Polyethylene Terephthalate(PET) Fiber by Roll-to-Roll Treatment in Atmospheric Ar/O_2 Dielectric Barrier Discharge(DBD) Plasma

In this work,polyethylene terephthalate(PET) fibers were continuously treated by atmospheric dielectric barrier discharge(DBD) in Ar mixed O2 plasma,and the discharge was characterized by electrical function and optical diagnostics.It is found that the interfacial adhesion strength between treated PET fiber and resorcinol formaldehyde latex(RFL)(little)-rubber was improved(about 50%) by the measurement of interfacial shear strength(IFSS) and peel test.The wettability was improved rapidly in the initial treatment time.It is considered that oxidation chemical reaction as the major role of PET fiber surface modification is ahead of the physical etching effect.The high density of atomic oxygen in the plasma by optical emission spectroscopy supports the purpose.According to the scanning electron micrograph(SEM) image in the work,the longer treatment time obviously caused physical etching effect,which shall be less responsible for the improvement of the wettability.

A Re-examination of Density Effects in Eddy Covariance Measurements of CO_2 Fluxes

Corrections of density effects resulting from air-parcel expansion/compression are important in interpreting eddy covariance fluxes of water vapor and CO2 when open-path systems are used. To account for these effects, mean vertical velocity and perturbation of the density of dry air are two critical parameters in treating those physical processes responsible for density variations. Based on various underlying assumptions, different studies have obtained different formulas for the mean vertical velocity and perturbation of the density of dry air, leading to a number of approaches to correct density effects. In this study, we re-examine physical processes related to different assumptions that are made to formulate the density effects. Specifically, we re-examine the assumptions of a zero dry air flux and a zero moist air flux in the surface layer, used for treating density variations, and their implications for correcting density effects. It is found that physical processes in relation to the assumption of a zero dry air flux account for the influence of dry air expansion/compression on density variations. Meanwhile, physical processes in relation to the assumption of a zero moist air flux account for the influence of moist air expansion/compression on density variations. In this study, we also re-examine mixing ratio issues. Our results indicate that the assumption of a zero dry air flux favors the use of the mixing ratio relative to dry air, while the assumption of a zero moist air flux favors the use of the mixing ratio relative to the total moist air. Additionally, we compare different formula for the mean vertical velocity, generated by air-parcel expansion/compression, and for density effect corrections using eddy covariance data measured over three boreal ecosystems.

Correlation between GEM Premier 3000 and Vitros5.1+5600, SYSMEX XN-9000 in Detecting Electrolytes and Red Blood Cell Volume

Objective: To explore the consistency and relevance of the results of the bedside rapid blood gas analyzer GEM premier 3000, the Vitros5.1+5600 biochemical immunoassay analyzer and the SYSMEX XN-9000 automatic blood cell analyzer in the central laboratory detecting serum potassium (K+), serumsodium (Na+), blood glucose (Glu), hemoglobin (Hb) and red blood cell volume (Hct). And to provide a reference for the accurate interpretation of the bedside blood gas analysis report. Method: Usually, ICU patients will be taken arterial blood gas, biochemical and blood samples through the arterial indwelling needle;at the same time patients’ potassium, serum sodium, blood glucose, hemoglobin and red blood cell volume will be detected. This study implemented paired t-test and correlation regression analysis on each group of data, and used the analysis quality requirements (allowable total error) of CLIA’88 proficiency testing program as the criteria for clinical acceptance. Results: The paired t-test showed that the serum potassium, serum sodium and blood glucose detected by GEM premier 3000 and Vitros5.1+5600 were significantly different;and the hemoglobin and red blood cell volume detected by GEM premier 3000 and SYSMEX XN-9000 were significantly different (P < 0.05). The Pearson correlation coefficients (r) of hemoglobin, red blood cell volume and red blood cell volume were 0.860, 0.886, 0.924, 0.841 and 0.856, respectively, and the above test items all had good correlations (P < 0.05). The average (SE) of the paired differences of K+, Na+, Glu, Hb and Hct detected by the two sets of instruments is less than the allowable error of CLIA’88, and the SE of blood Na+ and Hb is less than half of the allowable error of CLIA’88. Conclusion: The test results of GEM premier 3000, the central laboratory Vitros5.1+5600 and SYSMEX XN-9000 have good correlation, but the consistency is not good. The test results of GEM premier 3000 cannot replace the central laboratory.

A new method to measure the concentration of argon-xenon gas mixture

RGAs are widely used in molec Background RGAs are widely used in molecular component examination,impurity analysis,leak detection and test of vacuum system performance.However,RGAs have different sensitivities to different gases,and the sensitivities can change quickly and depend on so many parameters,which make its ability severely limited.Methods In thiswork we established a newpractical method to precisely measure noble gas ratio of argon-xenon gasmixture.Gaseous argon and xenon were controlled,respectively,by two mass flow controller(MFC).A variable leak valve(VLV)was used to introduce the gas mixture sample into the RGA measurement chamber.Gas mixtures with xenon concentration from 200ppm to 20000ppm(by mass)were introduced and tested by RGA.Results The time stability of RGA-measurement system was optimized to 2.1%.A good linearity of MFC-RGA response was achieved,verifying the reliability of RGA in measuring noble gas mixture with component concentration down to several hundred ppm level.Conclusions Since the approach we used in our experiment is gas-species independent,we believe that it can be popularized to other gas species when properly applied.