Wehrwissenschaftliche Institut für Schutztechnologien

Salts of 5,5′-azotetrazolate with alkali metal, alkaline earth metal and several trivalent cations were synthesized as potential initial explosives. The synthesis in water yields hydrates of these salts that were studied by NMR and vibrational spectroscopy as well as X-ray diffraction. Their thermal properties were studied by DSC and TG.

OBJECTIVES: Late-onset Crohn's disease (CD) may show a distinctive pattern of expression. The aim of our study was to describe the incidence or presentation of CD in the elderly and compare the outcomes in patients < 60 years or > or = 60 years at diagnosis. METHODS: The study included a population based inception cohort of all incident CD cases diagnosed in Brittany (France) between 1994 and 1997. Sixty-three patients were > or = 60 years and 201 were < 60 years at diagnosis. The physicians managing the patients used standardized questionnaires to collect the study data. The questionnaires on outcomes and treatments were completed in 2002. RESULTS: In patients > or = 60 years, the annual incidence was 2.5 per 10 persons and clinical features were similar to those in younger patients, except for a higher rate of colon involvement. Among older patients, those with diverticula (29/63, 46%) were more likely to have granulomas (58% vs 33% of patients without diverticula, P < 0.04), but the diagnosis of CD was confirmed by lesions remote from the diverticula in most cases (23/29). Early resection rates were not higher in older patients, who were less likely to require immunosuppressants or re-admission for CD flares, as compared to younger patients. Five year mortality in older patients was 16% but was unrelated to CD. CONCLUSIONS: In Brittany, the age specific incidence, clinical features, and prognosis of CD among the elderly are comparable to those in younger individuals. Colon involvement is more common. Concomitant diverticular disease is common and should prompt a search for CD lesions at other sites to confirm the diagnosis. Older patients are less likely to require immunosuppressants or admission for flares.

In contrast to vertebrates, the role of the neurotransmitter glutamate in learning and memory in insects has hardly been investigated. The reason is that a pharmacological characterization of insect glutamate receptors is still missing; furthermore, it is difficult to locally restrict pharmacological interventions. In this study, we overcome these problems by using locally and temporally defined photo-uncaging of glutamate to study its role in olfactory learning and memory formation in the honeybee, Apis mellifera. Uncaging glutamate in the mushroom bodies immediately after a weak training protocol induced a higher memory rate 2 d after training, mimicking the effect of a strong training protocol. Glutamate release before training does not facilitate memory formation, suggesting that glutamate mediates processes triggered by training and required for memory formation. Uncaging glutamate in the antennal lobes shows no effect on memory formation. These results provide the first direct evidence for a temporally and locally restricted function of glutamate in memory formation in honeybees and insects.

The aim of this study was to determine the efficacy of oral beta-carotene supplementation for the correction of an oxidant-antioxidant imbalance in cystic fibrosis (CF). We studied 24-patients with cystic fibrosis and 14 healthy controls. 13 CF-patients were allocated to a CF-supplementation group, which received 1 mg beta-carotene/kg BW/d up to a body weight (BW) of 50 kg, patients with a BW greater 50 kg received 50 mg beta-carotene/d for 12 weeks. For the following 12 weeks all patients of the CF-supplementation group were treated with 10 mg beta-carotene/d. Placebos with starch were applied to 11 CF-patients. Baseline plasma beta-carotene concentrations of CF patients (mean +/- SD, 0.08 +/- 0.04 mumol/l) were significantly lower than those of age-matched controls (o.3 +/- 0.1 mumol/l) (p < 0.001). beta-carotene concentrations of the CF-supplementation group increased rapidly and reached a value of 0.6 mumol/l after 12 weeks of supplementation. Normal values were measured for plasma ascorbate and alpha-tocopherol. Plasma retinol concentrations were in the lower normal range and did not increase during supplementation. Total antioxidative capacity in plasma of the CF-supplementation group increased after 12 weeks of supplementation at an extent of 12%. Positive influence was indicated by a decrease of plasma malondialdehyde. Thus oral beta-carotene supplementation is effective in normalizing status of beta-carotene and malondialdehyde in CF patients.

Abstract Additive Manufacturing (AM) becomes more and more focus of studies in the scientific community. Nevertheless, elastomers in 3D printing are still a relatively understudied topic despite their extensive use in machine components. The further understanding of the technologies and knowledge acquirement are fundamental steps towards the improvement of the printing process and the broadening of feasible applications of 3D printed elastomers. This work focused on thermoplastic polyurethanes printed with Fused Filament Fabrication (FFF) and investigated the effect of infill deposition angle and contour lines on the tensile and the stress relaxation behaviour. Samples were printed in alternating as well as unidirectional infill orientations, the latter without and with outlines. Tensile tests revealed that alternating orientations of 0°–90° and 45°–135° have a similar behaviour and benefit the integrity of the part. The fully unidirectional orientation at 90° hindered the tensile strength due to the absence of outlines and consequent delamination. All comparative analyses displayed a low influence of the raster angle at lower strains. Stress relaxation results showed similar behaviour for samples with outlines, without a clear effect of the infill orientations. In summary, contour lines are essential and an alternating orientation is recommended for better part integrity.

Abstract Glycidyl azide‐r‐(3,3‐bis(azidomethyl)oxetane) copolymers were synthesized by cationic copolymerization of epichlorohydrin and 3,3‐bis(bromomethyl)oxetane, using butane‐1,4‐diol as an initiator and boron trifluoride etherate as a catalyst, followed by azidation of the halogenated copolymer. The main objective of this work is the preparation of an OH‐terminated amorphous polymer with energetic content higher than that of the well‐known glycidyl azide homopolymer. The effect of experimental conditions, i.e., the rate of monomer feeding, on the final molecular weight and functionality of the copolymer has also been investigated. The obtained copolymers were extensively characterized to determine their composition and thermal stability. The heat of reaction for the polymerization of the halogenated key precursors has also been measured. It was found that even though both the operating conditions and the catalytic system were chosen in order to favor a living character of the polymerization, the final product seems to be the result of a combined living and active chain end mechanism. In particular, the latter is responsible for the formation of oligomers and not hydroxyl‐terminated chains. Nevertheless, the average number of OH groups is high enough to allow a cross‐linking of the polymeric chains, by addition of polyisocyanates and subsequent formation of inter‐chain urethanic bonds.

The title compound (systematic name: 4,10-dinitro-2,6,8,12-tetraoxa-4,10-diazatetracyclo[5.5.0.0(3,11).0(5,9)]dodecane), C(6)H(6)N(4)O(8), exhibits the highest density among known N-nitramines, due to its close-packed crystal structure. It may be regarded as consisting of a distorted hexagonal close-packed lattice formed by the isowurtzitane cages, with the nitro groups occupying the free space between the cages.

Abstract In the present work we describe synthesis and properties of 1,4‐diformyl‐2,3,5,6‐tetranitratopiperazine. The 1,4‐diformyl‐2,3,5,6‐tetranitratopiperazine turned out to be a powerful highly energetic compound. Its physical and chemical properties were investigated by theoretical as well as experimental methods. The detonation energy of 1,4‐diformyl‐2,3,5,6‐tetranitratopiperazine was determined to 5376 kJ/kg or 93% compared to HMX. Molecular and crystal structure of 1,4‐diformyl‐2,3,5,6‐tetranitratopiperazine was elucidated by single crystal X‐ray diffraction analysis. An interesting feature of the title substance, its rotamer equilibrium, was investigated by 2D NMR methods.

What we believe to be a new optical approach for the identification of mines and explosives by analyzing the surface materials and not only bulk is developed. A conventional manually operated mine prodder is upgraded by laser-induced breakdown spectroscopy (LIBS). In situ and real-time information of materials that are in front of the prodder are obtained during the demining process in order to optimize the security aspects and the speed of demining. A Cr4+:Nd3+:YAG microchip laser is used as a seed laser for an ytterbium-fiber amplifier to generate high-power laser pulses at 1064 nm with pulse powers up to E(p) = 1 mJ, a repetition rate of f(rep.) = 2-20 kHz and a pulse duration of t(p) = 620 ps. The recorded LIBS signals are analyzed by applying neural networks for the data analysis.

Abstract Als Calixarene werden cyclische Kondensationsprodukte aus para‐substituierten Phenolen und Formaldehyd bezeichnet. Vor allem wegen ihrer Rezeptoreigenschaften für Ionen und neutrale Moleküle nimmt das Interesse an ihnen immer noch zu. Einsatzmöglichkeiten zeichnen sich in den unterschiedlichsten Bereichen ab: Ob als neuartige Katalysatoren oder als Antioxidantien, ob als stationäre Phasen in der Chromatographie oder als Additive in Klebstoffen, die Palette der Möglichkeiten ist so groß wie die Variationsbreite in der chemischen Struktur von Calixarenen.

Venezuelan equine encephalitis virus (VEEV) belongs to the Alphavirus genus and several species of this family are pathogenic to humans. The viruses are classified as potential agents of biological warfare and terrorism and sensitive detection as well as effective prophylaxis and antiviral therapies are required.In this work, we describe the isolation of the anti-VEEV single chain Fragment variable (scFv), ToR67-3B4, from a non-human primate (NHP) antibody gene library. We report its recloning into the bivalent scFv-Fc format and further immunological and biochemical characterisation.The scFv-Fc ToR67-3B4 recognised viable as well as formalin and ß-propionolactone (ß-Pl) inactivated virus particles and could be applied for immunoblot analysis of VEEV proteins and immuno-histochemistry of VEEV infected cells. It detected specifically the viral E1 envelope protein of VEEV but did not react with reduced viral glycoprotein preparations suggesting that recognition depends upon conformational epitopes. The recombinant antibody was able to detect multiple VEEV subtypes and displayed only marginal cross-reactivity to other Alphavirus species except for EEEV. In addition, the scFv-Fc fusion described here might be of therapeutic use since it successfully inactivated VEEV in a murine disease model. When the recombinant antibody was administered 6 hours post challenge, 80% to 100% of mice survived lethal VEEV IA/B or IE infection. Forty to sixty percent of mice survived when scFv-Fc ToR67-3B4 was applied 6 hours post challenge with VEEV subtypes II and former IIIA. In combination with E2-neutralising antibodies the NHP antibody isolated here could significantly improve passive protection as well as generic therapy of VEE.

Abstract Salts of the 5,5′-azotetrazolate dianion with several different hydrazinium cations were pre­ pared. The compounds were characterized by elemental analysis, vibrational spectroscopy (IR, Raman) and multinuclear NMR spectroscopy ( 1 H, 13 C, 14 N). The crystal structures of the di-tert-butylhydrazinium, the ethylenedihydrazinium, the diguanidinium and the bis-triamino-guanidinium azotetrazolate were determined. The thermal, shock and friction sensitivities of all compounds were investigated and their explosion products were analysed. For the 5,5′-azotetr-azolate dianion the structure was calculated with density functional theory (B3-LYP). An NBO analysis was performed for the 5,5′-azotetrazolate dianion in order to understand the charge distribution of the dianion.

Abstract Solutions of N, N′ ‐azobistetrazolate salts in anhydrous hydrazine were reduced to salts of N, N′ ‐bistetrazolatohydrazine. Several salts of this highly energetic, nitrogen rich anion were prepared this way and characterized by elemental analysis, vibrational (IR, Raman) and multinuclear NMR spectroscopy ( 1 H, 13 C, 14 N). The crystal structure of the barium and hydrazinium salt were determined.

Die Rede von der Parallelgesellschaft speist sich aus zwei sehr unterschiedlichen Quellen, nämlich einerseits aus der Stadtforschung und andererseits aus einem migrationspolitischen Alarmismus der Medien. Allerdings geben beide Quellen einzeln nicht viel her, nur verknüpft scheint daraus überhaupt eine Debatte entstanden zu sein. Dennoch bleibt es erstaunlich, dass sie sich entfalten konnte und seit nunmehr gut acht Jahren sogar eine beträchtliche Wirkung zeigt. Bis heute gibt es fast keine systematische Auseinandersetzung mit Parallelgesellschaften und so etwas ist wohl auch kaum zu erwarten, weil institutionell geschlossene Gesellschaften in einer globalisierten Weltgesellschaft kaum vorstellbar sind. Doch gehen wir lieber langsam vor und kreisen die Thematik schrittweise ein. Dann wird auch deutlich, an welcher Stelle die Beiträge dieses Sammelbandes einhaken.

Abstract. Continuous measurements of surface mixed layer (SML), decoupled residual/convective layer (DRCL) and aerosol backscatter coefficient were performed within the Barcelona (Spain) boundary layer from September to October 2010 (30 days) in the framework of the SAPUSS (Solving Aerosol Problems by Using Synergistic Strategies) field campaign. Two near-infrared ceilometers (Jenoptik CHM15K), vertically and horizontally probing (only vertical profiles are herein discussed), were deployed. Ceilometer-based DRCLs (1761 ± 363 m a.g.l.) averaged over the campaign duration were twice as high as the mean SML (904 ± 273 m a.g.l.). Both DRCL and SML showed a marked SML diurnal cycle. Ceilometer data were compared with potential temperature profiles measured by daily radiosounding (twice a day, midnight and midday) to interpret the boundary layer structure in the coastal urban area of Barcelona. The overall agreement (R2 = 0.80) between the ceilometer-retrieved and radiosounding-based SML heights (h) revealed overestimation of the SML by the ceilometer (Δh=145 ± 145 m). After separating the data in accordance with different atmospheric scenarios, the lowest SML (736 ± 183 m) and DRCL (1573 ± 428 m) were recorded during warm North African (NAF) advected air mass. By contrast, higher SML and DRCL were observed during stagnant Regional (REG) (911 ± 234 m and 1769 ± 314 m, respectively) and cold Atlantic (ATL) (965 ± 222 m and 1878 ± 290 m, respectively) air masses. In addition to being the lowest, the SML during the NAF scenario frequently showed a flat upper boundary throughout the day possibly because of the strong winds from the Mediterranean Sea limiting the midday SML convective growth. The mean backscatter coefficients were calculated at two selected heights representative of middle and top SML portions, i.e. β500 = 0.59 ± 0.45 Mm−1 sr−1 and β800 = 0.87 ± 0.68 Mm−1 sr−1 at 500 m and 800 m a.g.l., respectively. The highest backscatter coefficients were observed during NAF (β500 = 0.77 ± 0.57 Mm−1 sr−1) when compared with ATL (β500 = 0.51 ± 0.44 Mm−1 sr−1) and REG (β500 = 0.64 ± 0.39 Mm−1 sr−1). The relationship between the vertical change in backscatter coefficient and atmospheric stability (∂θ/∂z) was investigated in the first 3000 m a.g.l., aiming to study how the unstable, stable or neutral atmospheric conditions of the atmosphere alter the distribution of aerosol backscatter with height over Barcelona. A positive correlation between unstable conditions and enhanced backscatter and vice versa was found.

This study shows the influence of RDX, Al and AP on the performance and reaction behavior of underwater explosives. The studied explosives varied in formulation, aluminium particle size and aluminium arrangement in the matrix. The different explosives were characterized by analyses of the detonation products after blasting in a closed vessel. The performance was measured by underwater explosions of charges with weights of 70 g, 250 g, 500 g and 1000 g. Einfluá von Aluminium und Ammoniumperchlorat auf die Leistung von Unterwassersprengstoffen Die vorliegende Arbeit beschreibt den Einfluß von RDX, Al und AP auf die Leistung und das Umsetzungsverhalten von Unterwassersprengstoffen. Die untersuchten Sprengstoffe unterschieden sich in ihren Formulierungen, den verwendeten Aluminiumsorten mit unterschiedlichen Korngrößen sowie der räumlichen Anordnung des Aluminiums in den Ladungen. Die Sprengstoffe wurden in einem Sprengkessel detonativ umgesetzt und die Detonationsprodukte analysiert. Außerdem wurden die Leistungsdaten durch Unterwassersprengungen mit Ladungen von 70 g, 250 g, 500 g und 1000 g ermittelt. Influence de l'aluminium et du perchlorate d'ammonium sur les performances des explosifs sous-marins La présente étude décrit l'influence du RDX, de l'Al et de l'AP sur les performances et le comportement de réaction d'explosifs sous-marins. Les explosifs étudiés se distinguent par leurs formulations, les types d'aluminium de granulométrie différente utilisés ainsi que la disposition spatiale de l'aluminium dans les charges. On a fait détoner les explosifs dans une cuve de détonation, puis analysé les produits de détonation. Par ailleurs, on a mesuré les performances en procédant à des explosions sous-marines avec des charges de 70 g, 250 g, 500 g et 1000 g.

Abstract The applicability of Additive Manufacturing for operational parts expands with the availability of new materials with specific properties. For elastomeric components produced with Fused Filament Fabrication, challenges associated with the printing process due to the nature of the material are faced. This paper investigates the effect of under-extrusion in this process regarding the feeding system and, predominantly, the moisture for thermoplastic polyurethanes with 3D printing experiments and thermomechanical testing. In particular, the filament flow control with a Bowden extruder provides a challenge. A microscopic analysis reveals the signs of under-extrusion, along with the influence of material drying to reduce the moisture content. The drying may depend not only on time and temperature, but also on mass and surface effects. Water uptake measurements exhibit absorptions up to 1.89% in weight, most of which take place during the first 24 h of the experiments. Tensile tests performed on samples with different moisture contents show their influence in the ultimate stresses. The moisture in the material causes under-extrusion induced failures. Those failures are less likely to happen at lower moisture levels, resulting in occasional higher tensile strengths. Overall, the importance of proper storage of the material throughout printing is verified, even under moderate humidity conditions due to its hygroscopic nature.

Abstract Salts of the 5,5′-azotetrazolate dianion with methylated ammonium and hydrazinium cations were prepared. The compounds were characterized by elemental analysis, vibrational (IR, Raman) and multinuclear NMR spectroscopy ( 1 H, 13 C, 14 N). The crystal structures of the di[ammonium], the bis[dimethylammonium] and the bis[trimethylhydrazinium] 5,5′-azo­ tetrazolate salts were determined. The thermal, shock and friction sensitivities of these com­ pounds were investigated and their explosion products were analysed.

Abstract Pyrolysis‐atmospheric pressure chemical ionization was used to study the thermal decomposition of the energetic material cyclotrimethylenetrinitramine (RDX) and characterization of the individual molecular ion products was accomplished by tandem mass spectrometry. The analysis was aided with pyrolysis mass spectra of the ( 15 N)‐ and perdeuterated RDX isotopes, and molecular formulae were derived for the m / z 46, 60, 74, 75, 85 and 98 molecular ions in the RDX pyrolysis mass spectrum. Equivalent fragments between the daughter ion mass spectra of the unlabeled and labeled RDX were determined in order to define a structure for each pyrolysis feature. Daughter ion mass spectra of pure reference compounds confirmed the identity of five of the six molecular ions. Perdeuterated RDX analyses provided evidence that m / z 74 and 75 are N , N ‐dimethylformamide and N ‐nitrosodimethylamine, respectively; m / z 46, 60 and 85 were identified as the protonated forms of formamide, N ‐methylformamide and dimethylaminoacetonitrile, respectively.

Abstract. This paper presents the summary of the key objectives, instrumentation and logistic details, goals, and initial scientific findings of the European Marie Curie Action SAPUSS project carried out in the western Mediterranean Basin (WMB) during September–October in autumn 2010. The key SAPUSS objective is to deduce aerosol source characteristics and to understand the atmospheric processes responsible for their generations and transformations – both horizontally and vertically in the Mediterranean urban environment. In order to achieve so, the unique approach of SAPUSS is the concurrent measurements of aerosols with multiple techniques occurring simultaneously in six monitoring sites around the city of Barcelona (NE Spain): a main road traffic site, two urban background sites, a regional background site and two urban tower sites (150 m and 545 m above sea level, 150 m and 80 m above ground, respectively). SAPUSS allows us to advance our knowledge sensibly of the atmospheric chemistry and physics of the urban Mediterranean environment. This is well achieved only because of both the three dimensional spatial scale and the high sampling time resolution used. During SAPUSS different meteorological regimes were encountered, including warm Saharan, cold Atlantic, wet European and stagnant regional ones. The different meteorology of such regimes is herein described. Additionally, we report the trends of the parameters regulated by air quality purposes (both gaseous and aerosol mass concentrations); and we also compare the six monitoring sites. High levels of traffic-related gaseous pollutants were measured at the urban ground level monitoring sites, whereas layers of tropospheric ozone were recorded at tower levels. Particularly, tower level night-time average ozone concentrations (80 ± 25 μg m−3) were up to double compared to ground level ones. The examination of the vertical profiles clearly shows the predominant influence of NOx on ozone concentrations, and a source of ozone aloft. Analysis of the particulate matter (PM) mass concentrations shows an enhancement of coarse particles (PM2.5–10) at the urban ground level (+64%, average 11.7 μg m−3) but of fine ones (PM1) at urban tower level (+28%, average 14.4 μg m−3). These results show complex dynamics of the size-resolved PM mass at both horizontal and vertical levels of the study area. Preliminary modelling findings reveal an underestimation of the fine accumulation aerosols. In summary, this paper lays the foundation of SAPUSS, an integrated study of relevance to many other similar urban Mediterranean coastal environment sites.