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Introduction: The management of an adequate donor pool is a constant and challenging task for blood centers in order to provide blood supply. New methods are required to streamline processes and attract (new) donors on a sustained basis. We present a digitalization method without media disruption and show the impact on our donors and their behavior. Methods: We designed and created a blood donation app that is fully compliant to all regulations and conforms to donor expectations. The presented digitalization serves the donor from preparation before the donation (health questionnaire) until completion of laboratory testing (medical report). Many other features are included and continuously attract donors to engage with the blood donation topic. Results: Eighteen months after the launch of our app, there are already 45,000 users. The digital questionnaire reduced the number of deferrals by 31.9% compared to the conventional paper questionnaire. Digital adopters show a significantly shorter donation interval (193 days compared to 316 days). In-app incentives include identification card, rapid laboratory testing results (time-to-results are two business days for 95%), and collection of badges among others. Conclusion: The presented method has changed our donor pool. Besides that, medical staff benefits from the automated process that allows focusing on the donor and their admission. On the other hand, the app has become a valid tool to manage our donor pool and attract first-time and young donors. [ABSTRACT FROM AUTHOR]

The uptake of hydrochloric acid (HCl), ethanol (C2H5OH), 1-butanol (1-C4H9OH), formic acid HC(O)OH and tri-fluoro acetic (CF3C(O)OH) acid to growing ice surfaces was investigated at temperatures between 194 and 228 K. HCl displayed extensive, continuous uptake during ice growth, which was strongly dependent on the ice growth velocity, the temperature of the ice surface and the gas phase concentration of HCl. Tri-fluoro acetic acid was also observed to be trapped in growing ice, albeit approximately an order of magnitude less efficiently than HCl, whereas the adsorption and desorption kinetics of ethanol, 1-butanol, formic acid on ice was not measurably different to that for non-growing ice, even at very large ice-growth rates. We present a parameterisation of the uptake coefficient for HCl on growing ice films (gamma_trap) and compare the results to an existing framework that describes the non-equilibrium trapping of trace gases on ice. The trapping of HCl in growing ice crystals in the atmosphere is assessed and compared to the gas- and ice-phase partitioning resulting from equilibrium surface adsorption and solubility. [ABSTRACT FROM AUTHOR]

We present a Chemical Ionisation Quadrupole Mass Spectrometer (CI-QMS) with radio-frequency (RF) discharge ion source through N2/CH3I as source of primary ions. In addition to the expected detection of PAN, peracetic acid and ClNO2 through well-established ion-molecule-reactions with I- and its water cluster, the instrument is also sensitive to SO2, HCl and acetic acid (CH3C(O)OH) through additional ion chemistry unique for our ion source. We present ionisation schemes for detection of SO2, HCl and acetic acid along with illustrative data sets from three different field campaigns underlining the potential of the CI-QMS with an RF discharge ion source as an alternative to 210Po. The additional sensitivity to SO2 and HCl makes the CI-QMS suitable for investigating the role of sulphur and chlorine chemistry in the polluted marine and coastal boundary layer. [ABSTRACT FROM AUTHOR]

GANDALF (Gas Analyzer for Nitrogen Dioxide Applying Laser-induced Fluorescence), a new instrument for the detection of nitrogen dioxide based on the laser-induced fluorescence (LIF) technique, is presented in this paper. GANDALF is designed for ground based and air-borne deployment with a robust calibration system. In the current setup, it uses a multi-mode diode laser (447-450nm) and performs in situ, continuous, and autonomous measurements with a laser pulse repetition rate of 5MHz. The performance of GANDALF was tested during the field experiment at a forested location with urban influence where NOx levels were between 0.12 and 22 parts per billion by volume (ppbv). Based on the field results, the limit of detection is estimated at 5-10 parts per trillion by volume (pptv) in 60s at a signal to noise ratio (SNR) of 2. The overall accuracy and precision of the instrument are better than 5% (1σ) and 0.5%+3pptv (1σmin-1), respectively. A comparison of nitrogen dioxide measurements based on several techniques during the field campaign is presented to explore methodic differences. [ABSTRACT FROM AUTHOR]

We describe the first instrument for measurement of the rate constant (s-1) for reactive loss (i.e. the total reactivity) of NO3 in ambient air. Cavity-ring-down spectroscopy is used to monitor the mixing ratio of synthetically generated NO3 (≈ 30-50 pptv) after passing through a flow-tube reactor with variable residence time (generally 10.5 s). The change in concentration of NO3 upon modulation of the bath gas between zero-air and ambient air is used to derive its loss rate constant, which is then corrected for formation and decomposition of N2O5 via numerical simulation. The instrument is calibrated and characterized using known amounts of NO and NO2 and tested in the laboratory with an isoprene standard. The lowest reactivity that can be detected (defined by the stability of the NO3 source, instrumental parameters and NO2 mixing ratios) is 0.005 s-1. An automated dilution procedure enables measurement of NO3 reactivities up to 45 s-1, this upper limit being defined mainly by the dilution accuracy. The typical total uncertainty associated with the reactivity measurement at the centre of its dynamic range is 16%, though this is dependent on ambient NO2 levels. Results from the first successful deployment of the instrument at a forested mountain site with urban influence are shown and future developments outlined. [ABSTRACT FROM AUTHOR]

We present an estimation of the uptake coefficient (γ) and yield of nitryl chloride (ClNO2) (f) for the heterogeneous processing of dinitrogen pentoxide (N2O5) using simultaneous measurements of particle and trace gas composition at a semi-rural, non-coastal, mountain site in the summer of 2011. The yield of ClNO2 varied between (0.035±0.027) and (1.38±0.60) with a campaign average of (0.49±0.35). The large variability in f reflects the highly variable chloride content of particles at the site. Uptake coefficients were also highly variable with minimum, maximum and average γ values of 0.004, 0.11 and 0.028±0.029, respectively, with no significant correlation with particle composition, but a weak dependence on relative humidity. The uptake coefficients obtained are compared to existing parameterizations based on laboratory datasets and with other values obtained by analysis of field data. [ABSTRACT FROM AUTHOR]

We report the characteristics and performance of a newly developed five-channel cavity ring-down spectrometer to detect NO3, N2O5, NO2, total peroxy nitrates (6PNs) and total alkyl nitrates (6ANs). NO3 and NO2 are detected directly at 662 and 405 nm, respectively. N2O5 is measured as NO3 after thermal decomposition at 383 K. PNs and ANs are detected as NO2 after thermal decomposition at 448 and 648 K. We describe details of the instrument construction and operation as well as the results of extensive laboratory experiments that quantify the chemical and optical interferences that lead to biases in the measured mixing ratios, in particular involving the reactions of organic radical fragments following thermal dissociation of PNs and ANs. Finally, we present data obtained during the first field deployment of the instrument in July 2015. [ABSTRACT FROM AUTHOR]