Investigating soil and groundwater quality at different scales in a forested catchment: the Waldstein case study

The impact of anthropogenic depositions on soil and groundwater quality has been the subject of numerous studies in the last two decades. However, the problem of linking results and models at different scales remains to be solved. A case study has been performed in the Fichtelgebirge region in South-East Germany. Data from this case study has been used to analyse scale dependences of spatial variance, autocorrelation lengths, and the interdependence of soil hydrological and soil chemical parameters. For soil suction, spatial variability increases stepwise with scale. Three different sources of variation could be identified, predominating at different ranges of scale, making a deterministic mapping feasible. Local SO₄ deposition explained much of the spatial pattern of SO₄ concentration in soil solution and in catchment runoff observed at different scales. This is mainly due to the fact that the sorption capacity of the soils in this region has been exceeded. Decreasing SO₄ deposition in the long term run is likely to enhance the influence of the soil, and reduces the correlation between deposition and soil solution concentration. NO₃ showed minimum variation at the county scale. This seems to be a reasonable representative elementary area for mapping regional NO₃ concentration patterns. For protons and Cl, neither observed spatial patterns nor the scale dependence of spatial heterogeneity could be explained adequately.     

Tissue Sampling and Homogenization in the Sub-Microliter Scale with a Nanosecond Infrared Laser (NIRL) for Mass Spectrometric Proteomics

It was recently shown that ultrashort pulse infrared (IR) lasers, operating at the wavelength of the OH vibration stretching band of water, are highly efficient for sampling and homogenizing biological tissue. In this study we utilized a tunable nanosecond infrared laser (NIRL) for tissue sampling and homogenization with subsequent liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis for mass spectrometric proteomics. For the first time, laser sampling was performed with murine spleen and colon tissue. An ablation volume of 1.1 × 1.1 × 0.4 mm³ (approximately 0.5 µL) was determined with optical coherence tomography (OCT). The results of bottom-up proteomics revealed proteins with significant abundance differences for both tissue types, which are in accordance with the corresponding data of the Human Protein Atlas. The results demonstrate that tissue sampling and homogenization of small tissue volumes less than 1 µL for subsequent mass spectrometric proteomics is feasible with a NIRL.     

Increased Reactor Performance versus Reactor Safety Aspects in Acrylate Copolymerization

The aim of reducing cycle times of semibatch‐polymerization processes requires systematic investigations of the kinetics, careful adjustment of the desired polymer properties, proper thermal reactor design and reliable reactor safety assessment [1]. As a concrete example, a semibatch‐copolymerization was carefully examined with respect to four different aspects. Thermo‐kinetics of the reaction were investigated with isoperibolic reaction calorimetry and GC. In order to obtain reliable values for the overall heat transfer coefficient of the production scale reactor, cooling experiments were carried out with solvent and final copolymer solution as reactor content. For consistent reactor safety assessment additional investigations are necessary including case studies of breakdown incidences. These simulations were performed with a mathematical model based on the GC data and experimental vapor pressure curves. As a result of these calculations, a reduction of reaction time from 10 to 6 hours was possible. To convert into practice, it must be ensured that even in this shortened time a product of the same quality is produced.     

Heterogen katalysierte Reaktivdestillation: Design und Scale‐up am Beispiel von Methylacetat

Reactive Distillation by Heterogeneous Catalysis: Design and Scale‐up Using Methyl Acetate as an Example Methyl acetate synthesis and hydrolysis is used to exemplify the design and scale‐up of heterogeneously catalyzed reactive distillations using Katapak‐S/‐SP. Different equilibrium and non‐equilibrium stage models and a rate‐based model are compared in order to clarify the level of complexity needed to predict the process behavior. An equilibrium stage model accounting for reaction kinetics is the best choice for methyl acetate reactive distillation. Reliable information on fluid dynamics of the used reactive distillation packing is needed for the fluid dynamic design in order to assure a wide operation range of the reactive distillation column. To verify the process model, experiments on the synthesis of methyl acetate have been performed in columns with different diameters. As a case study, the model‐based scale‐up is described for an industrial methyl acetate hydrolysis process.     

ON BROADWAY

On Broadway represents life in the 21st century city through a compilation of images and data collected along the 13 miles of Broadway that span Manhattan. The result is a new type of city view, created from the activities and media shared by hundreds of thousands of people. The project uses approximately 40 million data points and images and includes an application and an interactive installation.     

Model function to calculate the refractive index of native hemoglobin in the wavelength range of 250-1100 nm dependent on concentration

The real part of the complex refractive index of oxygenated native hemoglobin solutions dependent on concentration was determined in the wavelength range 250 to 1100 nm by Fresnel reflectance measurements. The hemoglobin solution was produced by physical hemolysis of human erythrocytes followed by ultracentrifugation and filtration. A model function is presented for calculating the refractive index of hemoglobin solutions depending on concentration in the wavelength range 250 to 1100 nm.     

Influence of α-dicarbonyl compounds to the molecular weight distribution of melanoidins in sucrose solutions: part 1

The correlations between formation of melanoidins and the content of α-dicarbonyl compounds and colour formation were studied in Maillard reaction model sucrose solutions at high treating temperatures (130 °C) corresponding to the industrial sucrose processing. Molecular weight distribution was determined by gel permeation chromatography (GPC) and α-dicarbonyls as high reactive intermediates of the Maillard reaction were detected by RP-HPLC and GC/MS. Referring to formation of melanoidins, new knowledge could be gained. The investigations clearly point out, that individual α-dicarbonyls are involved in formation of specific molecular weight fractions. 3-Deoxyhexosulose (3-DH) and methylglyoxal are the important α-dicarbonyl compounds in thermal-treated sucrose solutions. A low molecular weight fraction with a molecular weight range of <5,800 g/mol preferably occurs when 3-DH is formed in high concentrations. The high increase in intensity of a low molecular weight fraction is combined with a strong colour formation. In contrast to 3-DH, methylglyoxal promotes the formation of high molecular weight fractions between 6,600 g/mol and approximately 17,000 g/mol. Furthermore, model solutions with a high intensity of high molecular weight fractions show an early colour formation during the starting period of the reaction. Indeed, this early browning is not as intensive as the colour formation caused by the low molecular weight fraction during the later stage of the browning reaction. Out of this, 3-DH can be regarded as the most important intermediate for an intensive colour formation in sucrose solutions.     

Interrelation between crystal packing and small-molecule organic solar cell performance

X-ray investigations on single crystals of a series of terminally dicyanovinyl-substituted quaterthiophenes and co-evaporated blend layers with C(60) give insight into molecular packing behavior and morphology, which are crucial parameters in the field of organic electronics. Structural characteristics on various levels and length scales are correlated with the photovoltaic performance of bulk heterojunction small-molecule organic solar cells.     

pH-sensitive capsules as intracellular optical reporters for monitoring lysosomal pH changes upon stimulation

The concept of a long-term sensor for ion changes in the lysosome is presented. The sensor is made by layer-by-layer assembly of oppositely charged polyelectrolytes around ion-sensitive fluorophores, in this case for protons. The sensor is spontaneously incorporated by cells and resides over days in the lysosome. Intracellular changes of the concentration of protons upon cellular stimulation with pH-active agents are monitored by read-out of the sensor fluorescence at real time. With help of this sensor concept it is demonstrated that the different agents used (Monensin, Chloroquine, Bafilomycin A1, Amiloride) possessed different kinetics and mechanisms of action in affecting the intracellular pH values.