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81.
Cells are highly organized objects containing millions of molecules. Each biomolecule has a specific shape in order to interact with others in the complex machinery. Spatial dynamics emerge in this system on length and time scales which can not yet be modeled with full atomic detail. This review gives an overview of methods which can be used to simulate the complete cell at least with molecular detail, especially Brownian dynamics simulations. Such simulations require correct implementation of the diffusion-controlled reaction scheme occurring on this level. Implementations and applications of spatial simulations are presented, and finally it is discussed how the atomic level can be included for instance in multi-scale simulation methods.  相似文献   
82.
通过在传统的短路过渡电弧和射流过渡电弧的基础上进行创新,发展新型的焊接电弧,可以显著地提高电弧焊接在金属连接中的优越性。两种新的焊接电弧,forceArc~杂志焊接电弧和coldArc~焊接电弧可以在一个焊接电源上实现,对焊接生产具有现实意义。了解和掌握这些新型电弧的工艺特点,可以有效地将其应用到生产中,以此提高焊接产品的质量和焊接生产的经济效益。新型焊接电弧的出现使现有的有关焊前焊接接头准备的标准和规定,特别是有关坡口角度和焊接位置,需要重新考虑。新型焊接电弧可以应用于各种金属加工工业中的焊接生产,是对弧焊工艺的一个创新。  相似文献   
83.
Production-integrated environmental protection – Utilization of residues . Chemical plants as well as coal-fired powerstations utilize chemical reactions in order to produce materials or energy. Most of these reactions additionally produce gaseous, liquid, or solid residues. It is the main objective of production-integrated environmental protection to use these residues as suitable feedstocks in order to reduce environmental pollution and lower the consumption of raw materials. Several examples from the BASF Group will show how, by crossing the borders of the respective plant, reasonable solutions for material, or at least energetic, utilization of residues can be achieved. As a result of permanent efforts in production-integrated environmental protection over many years and despite increasing outputs the emissions of the chemical industry have been continuously reduced.  相似文献   
84.
Direct stimulation of soluble guanylate cyclase (sGC) represents a promising therapeutic strategy for the treatment of a range of diseases, including the severely disabling pulmonary hypertension (PH). Optimization of the unfavorable DMPK profile of previous sGC stimulators provided riociguat, which is currently being investigated in phase III clinical trials for the oral treatment of PH.

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85.
We investigated the dependence of unipolar diffusion charging of nanoparticles on the dielectric constant of the particle material experimentally. The examined nanoparticles (10–200 nm) cover a wide range of dielectric constant but have almost the same spherical or compact morphology. Measurements of both intrinsic charged fraction and mean charge per particle show very small differences among different materials. The level of the small difference is consistent with the estimation by Fuchs’ [(1963). On the stationary charge distribution on aerosol particles in bipolar ionic atmosphere. Geofisica Pura e Applicata, 56, 185–193] theory.  相似文献   
86.
87.
Systemic blood stream infections are a major threat to human health and are dramatically increasing worldwide. Pseudomonas aeruginosa is a WHO-alerted multi-resistant pathogen of extreme importance as a cause of sepsis. Septicemia patients have significantly increased survival chances if sepsis is diagnosed in the early stages. Affinity materials can not only represent attractive tools for specific diagnostics of pathogens in the blood but can prospectively also serve as the technical foundation of therapeutic filtration devices. Based on the recently developed aptamers directed against P. aeruginosa, we here present aptamer-functionalized beads for specific binding of this pathogen in blood samples. These aptamer capture beads (ACBs) are manufactured by crosslinking bovine serum albumin (BSA) in an emulsion and subsequent functionalization with the amino-modified aptamers on the bead surface using the thiol- and amino-reactive bispecific crosslinker PEG4-SPDP. Specific and quantitative binding of P. aeruginosa as the dedicated target of the ACBs was demonstrated in serum and blood. These initial but promising results may open new routes for the development of ACBs as a platform technology for fast and reliable diagnosis of bloodstream infections and, in the long term, blood filtration techniques in the fight against sepsis.  相似文献   
88.
The sizing accuracies of two widely used yet hitherto unevaluated optical particle counters (OPCs—Grimm Model 1.109 and Palas Model WELAS 2100) as well as one high-resolution, non-commercial OPC were evaluated. The measured data were compared to scattering intensity calculations based on Mie theory. Additionally, the counting efficiency for all three counters was measured, as was the influence of coincidence effects for the OPC with the lowest (manufacturer specified) upper concentration limit.Beside the traditional polystyrene latex calibration, a little-known, very fast and precise “multimodal” calibration method was used, which is based on the simultaneous generation of up to eight sharp multiple-charge modes from polydisperse di-ethyl-hexyl-sebacate (DEHS) particles by electrical mobility classification.  相似文献   
89.
Within the paper a short overview is given regarding the application of advanced materials in the shipbuilding world. The trends for application of high‐strength structural steel, aluminium alloys and composites as well as their limits and restrictions are mentioned. Specific attention is paid to material and corrosion problems observed in shipbuilding and ships in service. As main topics the application of high‐tensile strength structural steel for ship structural members, for ballast water tanks and the involved corrosion problems, the fatigue resistance and “undermatch” situation of welded aluminium alloys compared to steel as well as the corrosion of composites, i.e. osmosis, are mentioned. New developments of ships, e.g. high‐speed crafts and wigs, are pointed out. Conclusions for further research and development in the material field are drawn. The importance of the inter‐relationships amongst the improved material properties, design and calculation aspects as well as the fabrication technologies are stated.  相似文献   
90.
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