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991.
Definition of the problem Medical confidentiality, which is one of the main pillars of medical ethics, has taken a decisive role in the latest discussions about the improvement of child protection laws. Inexplicit and plurivalent arrangements and procedures of how to legally handle child abuse cases when persons with legal custody refuse to take further support are seen as an obstacle for effective child protection. Arguments Non-specific legal regulations lead to task uncertainty and hesitation on the side of health care professionals, which can result in the delay or even prevention of necessary actions. Therefore, new laws on the federal level have been passed in order to establish certainty with regard to professional secrecy and in order to foster networking among the actors in the field of child protection. Conclusion The paper analyses and discusses these legal attempts at strengthening child protection. Although some of the federal laws have the potential of clarification, the great number of laws and their explication restricts their impact.  相似文献   
992.
The transport of positively charged redox active species through spiropyran-modified nanopores in silica colloidal films was controlled using light. The silica colloidal films were comprised of 18 layers of face centered cubic (fcc)-packed 170 nm silica spheres. The surface of the films was first modified with amines, which were then used to attach the spiropyran moiety to the surface. The limiting current of a positively charged redox active species through the spiropyran-modified nanopore decreased after irradiation with UV light at pH 6.6. When the silica colloidal film was subsequently irradiated with visible light the initial limiting current was restored.  相似文献   
993.
994.
Large Eddy Simulation (LES) is used to model two lake sidearms subject to heating from solar radiation and cooling from a surface flux. The sidearms are part of Lake Audrey, NJ, USA and Lake Alexandrina, SA, Australia. The simulation domains are created using bathymetry data and the boundary is modelled with an Immersed Boundary Method. We investigate the cooling and heating phases with separate quasi-steady state simulations.  相似文献   
995.
In this work we analyzed the cathodic reactions of an important ionic liquid (IL) based electrolyte solution, namely lithium bis(trifluoromethylsulfonyl)imide (LiTFSI)/N-methyl-N-methylpyrrolidinium (BMP) TFSI. In situ FTIR spectroscopy was used for the analysis of gaseous products of the electrochemical decomposition of this IL solution during cathodic polarization of lithium metal and graphite electrodes. The main volatile product of the reductive decomposition of the anion in these BMPTFSI solutions is trifluoromethane. BMP cations decompose to mixtures of tertiary amines and hydrocarbons. The composition of the products is influenced by the nature of the anode material. Graphite possesses a catalytic activity in the electroreduction process of BMP cations which occurs along with their intercalation into the graphite structure. The liquid phase after cathodic polarization of graphite electrodes was analyzed by multinuclear NMR spectroscopy coupled with FTIR spectroscopy. 15N NMR and FTIR spectra revealed an increase in the Li cations content in the electrolyte solution, as a result of BMP cations decomposition during repeated cycling of graphite electrodes.  相似文献   
996.
This paper describes the deposition of zinc(II) with anodic stripping voltammetry on the boron-doped diamond electrode. We illustrate the dependency of several parameters on the magnitude of the oxidation peak and try to optimize the method. The supporting electrolyte was found to influence the oxidation peak magnitude. Compared with acetic acid, the most frequently used supporting electrolyte, ammonia buffer solution leads to a four times higher signal. We assume that the formation of zinc complexes, primarily tetraaminezinc(II), are responsible for the better response. Further factors studied and assessed include buffer pH, buffer concentration, deposition potential, deposition time and scan rate. With the improved conditions, a final detection limit of 5 ppb was accomplished.  相似文献   
997.
Scanning electron photomicrography, x-ray energy dispersion spectroscopy and metallographic sectioning techniques were combined to determine some topographical and tribological characteristics of a high temperature, self-lubricating composite. This bearing material consists of a porous nichrome alloy matrix, vacuum impregnated with a CaF2-BaF2 eutectic. The results indicate that a specific, multistep post-machining treatment of a composite part may be advantageous for effective high temperature service. Unique topographical and compositional changes of the sliding surfaces of the composite were observed after short term, low load use at a 1,200 F temperature in a helium environment. The data, as represented by high magnification photomicrographs and x-ray spectra, can be used as inspection tools (visual standards) for examining parts machined from the subject bearing material.  相似文献   
998.
Effect of combined processing by the equal-channel angular hydroextrusion (ECAH), direct hydroextrusion (HE) and drawing (D) on properties of copper wire is discussed in the paper. The technique has been for the first time employed for hardening lengthy copper rods and wire and reaching the ultimate tensile strength σ = 686 MPa and the elongation to failure δ = 2% in the 0.5 mm diameter copper wire. These contrast with σ = 556 MPa and δ = 1.4% resulted from processing without ECAH. Electrical conductivity of the highest strength wire produced with ECAH and conductivity of a hardened wire produced without ECAH differ negligibly.  相似文献   
999.
The effect of a plant extract (prepared from olive, garlic, onion and citrus with sodium acetate as a carrier) on the viability of yogurt starter cultures was studied. Nonfat yogurt was prepared with various levels of supplements: plant extract (0, 0.5 or 1.0%, w/v) or l-cysteine HCl (0.014 or 0.028%, w/w). Microbial and physicochemical analyses were conducted weekly for 50 days. Fermentation time increased for supplemented yogurts compared with the non-supplemented yogurt. Lactobacillus bulgaricus counts in supplemented yogurts were >6 log cfu mL?1 for a longer time (7–21 days) compared with the non-supplemented yogurt. Streptococcus thermophilus counts in all yogurts were > 6 log cfu mL?1 throughout the storage. Overall, redox potential and titratable acidity of yogurts on day 50 were greater compared with day 1, but pH and syneresis were less. Plant extract at 0.5% enhanced L. bulgaricus viability in nonfat yogurt while least affecting the physicochemical characteristics.  相似文献   
1000.
百欧仕EGSB厌氧处理PTA废水工程实例分析   总被引:1,自引:0,他引:1  
Biothane(荷兰百欧仕)公司是一家国际性污水处理公司,其在全世界已拥有500多项污水处理业绩。本工程实例是采用百欧仕的EGSB厌氧技术处理对苯二甲酸(PTA)污水,经过一年的实际运行,容积负荷率逐步提升到约10-15kgCOD/m3.d,SCOD的去除率保持在45-65%,苯甲酸去除率达约90%。经2个月时间的启动驯化期后,当进水PTA浓度低于800mg/L时,去除率可稳定在90%以上。偏苯三酸则需1年的滞后期后去除率稳定在80-90%。  相似文献   
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