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Experiments on impact craters and impact ionization of dust particles have been performed using iron microparticles from a 2‐Mv Van de Graaff accelerator. The particle velocity υ ranged from 0.2 to 40 km/sec and the mass m ranged from 1 × 10−15 g to 5 × 10−10 g. The analysis and mass determination of iron microspheres on smooth targets and of iron layers of the projectile in the middle of impact craters have been done with an electron microprobe. The Kα radiation emitted by the iron layer in the crater has been measured as a function of mass and velocity of the projectile. The radiation measurement gives, in combination with the crater diameter D, a means for the determination of the projectile parameters m and υ. The targets used were Ag, Al, Cu, Cd, and W. Within an error of approximately 20% the total mass of the iron projectile has been found inside the craters in W, Cu, and Al targets at velocities of ≤13 km/sec. The impact ionization has been studied for impact velocities of up to 40 km/sec and projectile masses of down to 10−15g. The yield of either ions or electrons, normalized to the incident mass m, can be described by an empirical relation of the form Q = const ƒ(θ, υ) · mα · υβ, where θ is the angle of incidence. Analysis of impact ionization has been applied to extremely sensitive detectors of cosmic dust particles. The impact cratering and ionization are discussed in terms of shock effects by applying the Rankine‐Hugoniot theory. The energy partition in the form of kinetic energy and internal energy (e.g., elastic compression and irreversible heating) is discussed as a function of the velocity of iron particles impacting the targets Al, Cu, W, and Au. As a result, W and Au are targets that transform a greater fraction of the primary energy into heating and ionization of projectile material.

Background: A new pneumatic tube system to transport red blood cell concentrates (RBCC) and fresh frozen plasma (FFP) was to be evaluated, followed by integration into the quality management system. Material and Methods: First, with the pneumatic tube system we transported 12 RBCC on day 35 after production. We estimated hemoglobin, hemolysis rate, ATP, potassium, LDH and lactate of the RBCC before and after transportation. In a second experiment, we transported 12 RBCC on day 10 after production. We tested these 12 RBCC for hemolysis rate, potassium and ATP, and compared them to 12 RBCC of the control group on days 10, 20, 30, and 35 after production. At the end of storage, all were tested for bacterial contamination. 36 FFP units were transported in frozen state over the same distance. Upon thawing, the samples were tested for factor VIII, antithrombin activity, and sterility. Results: The pneumatic tube transport of RBCC at the end of their usability and on day 10 after production including storage did not lead to any significant differences with regard to the tested parameters before and after transport. Factor VIII and antithrombin activities in all FFP units were between 70–100%. All 36 FFP were sterile and not damaged by the transportation. Conclusion: Transport of RBCC and FFP in a pneumatic tube did not have any negative effect on the quality and storage stability of the products. By using this pneumatic tube system, blood products can be transported safely, fast and efficiently within a clinical center.