The modified outflow funnel — A device to assess the flow characteristics of powders

Flow regulators are added to solid pharmaceutical formulations to improve the flow properties of powder mixtures. During the blending process the glidants adsorb successively at the surface of the host particles and thus lead to a reduction of attractive forces. A large variety of flow additives based on silicon dioxide is commercially available, but not all glidants are just as well suited for each technological problem or each cohesive bulk powder. To assess the improvement of the flowability parameters caused by a glidant a classification system and an adequate measuring device is needed. We would like to present a new measuring device to evaluate the flow enhancing potency of glidants. The modified outflow funnel features a stirrer that acts in the region of bulk arches obstructing the outflow process of a cohesive powder. By destruction of the bulk arches powder outflow is enabled and the time needed for emanation can be measured as a parameter of the flow properties. In addition other measuring parameters like the force needed to destroy the bulk arches are capable to evaluate the flowability of the powder mixture. Binary powder mixtures consisting of corn starch and flow regulator were blended in a Turbula® mixer for a defined period of time. The flow regulators were represented by fumed silica and a selection of various types of SIPERNAT^® precipitated silica provided by Evonik Degussa GmbH, Hanau, Germany. Flowability parameters of the mixtures were characterized with a modified outflow funnel, Hausner Ratio and a shear tester.     

Irradiation-Assisted Stress-Corrosion Cracking of Nitinol During eBeam Sterilization

Medical device fractures during gamma and electron beam (eBeam) sterilization have been reported. Two common factors in these device fractures were a constraining force and the presence of fluorinated ethylene propylene (FEP). This study investigated the effects of eBeam sterilization on constrained light-oxide nitinol wires in FEP. The goal was to recreate these fractures and determine their root cause. Superelastic nitinol wires were placed inside FEP tubes and constrained with nominal outer fiber strains of 10, 15, and 20%. These samples were then subjected to a range of eBeam sterilization doses up to 400 kGy and compared with unconstrained wires also subjected to sterilization. Fractures were observed at doses of >100 kGy. Analysis of the fracture surfaces indicated that the samples failed due to irradiation-assisted stress-corrosion cracking (IASCC). This same effect was also observed to occur with PTFE at 400 kGy. These results suggest that nitinol is susceptible to IASCC when in the presence of a constraining stress, fluorinated polymers, and irradiation.     

Dimensions of psychotherapy in private practice.

Categorical approaches to psychotherapy on 4 bipolar dimensions are presented, including emotional intensity, location of problem, location of therapy, and location of responsibility. By means of a questionnaire, 142 psychotherapists in private practice were surveyed regarding types of patients treated, techniques utilized, clinical specialty areas, and self-ratings on the 4 dimensions. Of the 142 Ss, 41% were psychologists; 32% were marriage, family, and child counselors; 14% were psychiatrists; 9% were social workers; and 4% were psychological assistants or other specialists. Therapists whose theoretical orientation suggested conceptual clarity produced more discriminating responses on the dimensions, whereas therapists with conflicting orientations made less discriminating responses. Practitioners appeared to differ most along those dimensions over which they had practical control. (1 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Glucosuria of pregnancy: frequency of diabetes mellitus and renal glucosuria (author's transl)

From 1974 to 1979 352 pregnant women were referred to our diabetic outpatient clinic because of glycosuria during pregnancy. In 118 women (34%) oral glucose tolerance tests revealed a pathologic glucose tolerance. In 234 pregnant women (66%) a "renal glycosuria of pregnancy" was found to be the cause for the observed glycosuria. A pathologic glucose tolerance was relatively more frequent in the 3rd trimenon, whereas renal glycosuria was observed to be more frequent in the second trimenon.     

Experimental Study of Strengthening an RC Bridge Deck by Adding a Concrete Overlay

The present contribution focuses on the experimental investigation of moisture distribution profiles of a reinforced concrete bridge deck determined before, during and after adding a concrete overlay. By means of a non‐destructive system, the mass water content distributions were measured in the existing bridge deck as well as in the concrete overlay. Furthermore, the in situ measurements were accompanied by a comprehensive laboratory test programme. Water desorption isotherms and ultimate drying shrinkage strain were determined on specimens made of both the substrate and overlay concrete. Moreover, moisture distributions and shrinkage strains were measured on concrete prisms stored under uniform climatic conditions. Comparison of in situ measurements with lab test results allows a better understanding of the impact of environmental influences on the bonded overlay behaviour. Comparison of in situ measurements with previous lab test results allows the assessment of the effectivity of surface preparation by high‐pressure water jetting and, hence, the examination of the significance of results from composite lab tests for real bridge decks strengthened by overlays. A comparison of an experimental and numerical study of restraint effects exerted from the substrate concrete on the overlay will be presented in an accompanying paper.     

Characterization of Transformation Temperatures with the Bend and Free Recovery Technique: Parameters and Effects

This study was conducted to investigate factors such as the deformation strain, straining temperature, and the number of testing cycles on the measurement of transformation temperatures using the bend and free recovery (BFR) technique. Ti-56.0%Ni wire with approximately 40% cold work and a 2 mm diameter was heat treated in an air furnace for 10 min at 490 °C to obtain an A _f of approximately 21 °C. Wire specimens were deformed with one of two mandrels to apply an outer fiber strain of 2.4 or 5.8%. Deformation was performed at one of four straining temperatures: 0, ?30, ?50, or ?65 °C. Specimens were tested ten times to investigate the effect of repeated testing. The resulting BFR curves were analyzed to determine the trends in the R-phase start ( $ R_{{\text{s}}}^{\prime} $ ) and austenite finish (A _f) temperatures. For specimens strained at both 2.4 and 5.8% there was no detectable change in A _f resulting from changes in the deformation temperature. Increasing the deformation strain from 2.4 to 5.8% tended to increase the measured A _f by approximately 1 °C independent of deformation temperature. Repeat testing seemed to result in a slight increase in A _f but the intrinsic scatter of the BFR data made it impossible to conclusively identify a trend.     

Comprehensive study of concrete creep,shrinkage, and water content evolution under sealed and drying conditions

A comprehensive study of the time‐dependent behaviour of concrete, enhanced by measuring the evolution of the respective mass water content, is presented. Compressive creep as well as shrinkage are investigated on sealed and unsealed specimens in terms of the concrete age at loading of 2, 7, and 28 days, respectively, at a loading level of 30% of the compressive strength at loading. In addition, on the basis of the collected measurement data, the impact of load application on the moisture content is studied and the Pickett effect is re‐examined. The obtained set of material data consists of basic and drying creep strains for different concrete ages at loading, autogenous shrinkage strains as well as combined autogenous and drying shrinkage strains, the evolution of the mass water content, the water desorption isotherm, and the time‐dependent evolution of Young's modulus and the compressive strength. It provides a consistent set of material data for a particular concrete grade and will be available for calibrating and validating concrete models.     

Mercury(II) sorption to two Florida Everglades peats: evidence for strong and weak binding and competition by dissolved organic matter released from the peat

The binding of mercury(II) to two peats from Florida Everglades sites with different rates of mercury methylation was measured at pH 6.0 and 0.01 M ionic strength. The mercury(II) sorption isotherms, measured over a total mercury(II) range of 10(-7.4) to 10(-3.7) M, showed the competition for mercury(II) between the peat and dissolved organic matter released from the peat and the existence of strong and weak binding sites for mercury(II). Binding was portrayed by a model accounting for strong and weak sites on both the peat and the released DOM. The conditional binding constants (for which the ligand concentration was set as the concentration of reduced sulfur in the organic matter as measured by X-ray absorption near-edge structure spectroscopy) determined for the strong sites on the two peats were similar (Kpeat,s = 10(21.8 +/- 0.1) and 10(22.0 +/- 0.1) M-1), but less than those determined for the DOM strong sites (Kdom,s = 10(22.8 +/- 0.1) and 10(23.2 +/- 0.1) M-1), resulting in mercury(II) binding by the DOM at low mercury(II) concentrations. The magnitude of the strong site binding constant is indicative of mercury(II) interaction with organic thiol functional groups. The conditional binding constants determined for the weak peat sites (Kpeat,w = 10(11.5 +/- 0.1) and 10(11.8 +/- 0.1) M-1) and weak DOM sites (Kdom,w = 10(8.7 +/- 3.0) and 10(7.3 +/- 4.5) M-1) were indicative of mercury(II) interaction with carboxyl and phenol functional groups.     

Neutron lifetime measured by monitored storing of ultra-cold neutrons

The method of measuring the neutron β-decay lifetime τ_β by storage of ultra-cold neutrons (UCN) with simultaneous recording of inelastically scattered neutrons is presented. The result of the measurement is τ_β [s]=885.4±0.9_stat±0.4_syst.     

Exploring MARS: developing indoor and outdoor user interfaces to a mobile augmented reality system

We describe an experimental mobile augmented reality system (MARS) testbed that employs different user interfaces to allow outdoor and indoor users to access and manage information that is spatially registered with the real world. Outdoor users can experience spatialized multimedia presentations that are presented on a head-tracked, see-through, head-worn display used in conjunction with a hand-held pen-based computer. Indoor users can get an overview of the outdoor scene and communicate with outdoor users through a desktop user interface or a head- and hand-tracked immersive augmented reality user interface.