Produktionsintegrierter Umweltschutz — Verminderung von Reststoffen,gezeigt anhand ausgeführter Beispiele

Practical examples of production-related environmental protection and volume reduction in residual substances . Minimizing the volume of residual substances produced in chemical production processes is a matter of growing significance. One example is the production of toluylene diisocyanate where HCl gases generated as by-products are reclaimed by a special HCl electrolysis process and subsequently used in the production of precursors for toluylene diisocyanate. Another example is a combined disposal system for sewage sludge and for a particular chlorine-laden residue (a chlorinated hydrocarbon). Once this plant had gone on stream it was possible both to reduce considerably the volume of waste to be dumped in the landfill and to discontinue the incineration of the chlorinated hydrocarbon at sea.     

Functional properties of protein preparations from amaranth seeds in model system

The gross chemical composition and functional properties (solubility, emulsifying and foaming properties) of different amaranth protein preparations were studied in model systems and were compared to those of casein and soy protein isolates. Preparations of alkaline-soluble total protein, albumin, globulin, and glutelin-like alkaline-soluble residual protein were produced from two different types of defatted amaranth meals by extraction and fractionation. Although similarity can be shown between protein patterns of legumes (including soy) and amaranth, the emulsifying and foaming properties of amaranth protein preparations are relatively poor in comparison to the reference proteins, except foaming properties of albumin preparations. Nevertheless, taking in mind that these properties depend on interactions with other food components and textural requirements of individual food products, the amaranth protein preparations may be treated as potential protein sources and food ingredients.     

Which fluid space is affected by ultrafiltration during hemodiafiltration?

Ultrafiltration (UF) is a common procedure performed during almost all dialysis sessions. During UF, several liters of fluid are removed; however, what proportion of this fluid is removed from which fluid space could not be clinically measured easily until now; we designed this study to evaluate the fluid spaces most affected by UF. This is a prospective cohort study of 40 prevalent chronic hemodialysis patients receiving thrice weekly hemodiafiltration (HDF). We measured the patients' fluid spaces using a whole‐body bioimpedance apparatus to evaluate the changes of fluid spaces before and immediately after the HDF sessions. We recorded the data on fluid spaces, UF volume, and blood pressures. The cohort consisted of 40 prevalent HDF patients, aged 60.0 ± 5.2 years (37.5% men; 27.5% people with diabetes), and body weight 71.03 ± 15.48 kg. Achieved UF was 2.38 ± 0.98 L on HDF (measured fluid overload: 2.35 ± 1.44 L). The extracellular fluid (EC) volume decreased from 16.84 ± 3.52 to 14.89 ± 3.06 L (P < 0.0001) and intracellular fluid (IC) volume from 16.88 ± 4.40 to 16.55 ± 4.48 L (P = 0.45). Although urea volume of distribution remained effectively unchanged (31.38 ± 7.28 vs. 30.70 ± 7.32 L; P = 0.45), the degree of EC volume overload decreased from 13.60% ± 7.30% to 3.83% ± 8.32% (P < 0.0001). The mean arterial pressure also decreased from 122.95 ± 19.02 to 108.50 ± 13.91 mmHg (P < 0.0001). We conclude that source of net fluid loss by ultrafiltration is almost exclusively the EC fluid space. The intracellular fluid space is not significantly affected immediately after HDF.     

CFD models in the development of electrical waste recycling technologies

Nowadays electrical waste (EW) recycling has become a practical way to provide raw material for new devices. Computer parts such as memory, motherboard or other parts contain large amount of metals from which the recovery of precious metals and copper represents the highest economical potential. With a proper chemical treatment these metals can be efficiently extracted and separated from the actual waste. For this task a specially designed leaching reactor, equipped with a perforated rotating drum, was used. This work is aimed at investigating if computational fluid dynamics (CFD) tools can be efficiently applied to model the chemical reactor used to dissolve the metals from the EW. First a hybrid CFD-compartment approach was developed to describe the dissolution process in the leaching reactor while the CFD models were used to model the hydrodynamics of the process. Based on the detailed model containing momentum and component mass balance the developed simulator could be used to enhance the performance of the existing reactor system. For the modelling studies COMSOL Multiphysics was used as CFD software.     

利用高温二维液相色谱对功能化聚烯烃进行表征

二维液相色谱（2D-LC）提供了合成聚合物和生物聚合物分子异质性的不同方面的信息。聚烯烃材料的2D-LC分析需要高温,但聚烯烃的高温二维液相色谱（HT-2D-LC）分析条件却未见报道。通过高温相互作用液相色谱系统（根据分析物分子化学成分的差异进行分离）和体积排阻色谱（SEC）（根据分析物分子摩尔质量的不同进行分离）的联用,乙烯-乙酸乙烯酯共聚物的完整HT-2D-LC分离第一次得以实现。     

Geography- and infrastructure-aware topology design methodology for broadband access networks (FTTx)

We present a topology design methodology for broadband (FTTx) access networks. The calculations are based on real geographic data (digital maps) and infrastructural information of the targeted area, using detailed and realistic cost models in order to provide results of practical interest. The developed heuristics offer low time consumption and nearly optimal solutions for the highly complex problem of minimal cost network deployment, due to the properly chosen and customized heuristic algorithms for the various network technologies. We review the specific properties of the FTTx network technologies, present a formal representation of the problem including a detailed cost function and network model and discuss complexity issues. The various solution techniques are presented along with case studies of real-life scenarios in order to show the potential of the methodology. The developed heuristic algorithms offer an approximation of the optimum within 10–15%, while time consumption remains in the range of a few minutes, even for large-scale scenarios with 10,000s of customers. Beyond topology design, the results provided by these methods are useful for a preliminary CAPEX estimation and techno-economic comparison.     

Compound-specific chlorine isotope analysis: a comparison of gas chromatography/isotope ratio mass spectrometry and gas chromatography/quadrupole mass spectrometry methods in an interlaboratory study

Chlorine isotope analysis of chlorinated hydrocarbons like trichloroethylene (TCE) is of emerging demand because these species are important environmental pollutants. Continuous flow analysis of noncombusted TCE molecules, either by gas chromatography/isotope ratio mass spectrometry (GC/IRMS) or by GC/quadrupole mass spectrometry (GC/qMS), was recently brought forward as innovative analytical solution. Despite early implementations, a benchmark for routine applications has been missing. This study systematically compared the performance of GC/qMS versus GC/IRMS in six laboratories involving eight different instruments (GC/IRMS, Isoprime and Thermo MAT-253; GC/qMS, Agilent 5973N, two Agilent 5975C, two Thermo DSQII, and one Thermo DSQI). Calibrations of (37)Cl/(35)Cl instrument data against the international SMOC scale (Standard Mean Ocean Chloride) deviated between instruments and over time. Therefore, at least two calibration standards are required to obtain true differences between samples. Amount dependency of δ(37)Cl was pronounced for some instruments, but could be eliminated by corrections, or by adjusting amplitudes of standards and samples. Precision decreased in the order GC/IRMS (1σ ≈ 0.1‰), to GC/qMS (1σ ≈ 0.2-0.5‰ for Agilent GC/qMS and 1σ ≈ 0.2-0.9‰ for Thermo GC/qMS). Nonetheless, δ(37)Cl values between laboratories showed good agreement when the same external standards were used. These results lend confidence to the methods and may serve as a benchmark for future applications.     

Building a multimedia ISDN PC

A personal-computer-based architecture that uses graphics methods to improve cooperative multimedia work over integrated services digital networks (ISDNs) is discussed. The system supports cooperative multimedia work by providing real-time video, graphics, and speech. The system requirements, components, and general architecture are considered, as is the implementation of the system     

High performance liquid chromatographic detection of a strongly retained pigment fraction in Capsicum annuum

A new colour pigment fraction was detected in Capsicum annuum by high performance liquid chromatography. Surprisingly the pigment was strongly bound both to silica and octadecylsilica surfaces indicating that its molecular mass is probably high. Peak purity tests proved that the fraction is not homogeneous and the degree of inhomogeneity depends on the wavelength used for the peak purity test. The spectra taken at one minute intervals of the peak were strikingly different supporting the above conclusions. It is possible that this highly lipophilic pigment is a secondary product of the ripening and processing procedures and is a mixture of individual pigments covalently bound to each other.