Physikalische und mechanische Eigenschaften von Polyester-Polyamid-bikonstituenten Fasern

In a pilot plant biconstitusent fibres with poly(ethylene terephthalate) as main component and poly(caproamid) as second component were produced. Their microstructure, their behaviour during melting and crystallization, some dynamic-mechanic and mechano-textile properties as well as some electrostatic, hygroscopic and dyeing properties were determined. The biconstituent fibres have a low capability for electrifying and tend to show a “pilling”-effect. Their dyeing abilities open possibilities for interesting dyeing effects. An aim of the investigation was to clear some changes in the physical and mechanical properties of the biconstituent fibres from the view of their fibrille-matrix-structure and from the mutual effect between the two components at the interphase.     

The SHARC framework for data quality in Web archiving

Web archives preserve the history of born-digital content and offer great potential for sociologists, business analysts, and legal experts on intellectual property and compliance issues. Data quality is crucial for these purposes. Ideally, crawlers should gather coherent captures of entire Web sites, but the politeness etiquette and completeness requirement mandate very slow, long-duration crawling while Web sites undergo changes. This paper presents the SHARC framework for assessing the data quality in Web archives and for tuning capturing strategies toward better quality with given resources. We define data quality measures, characterize their properties, and develop a suite of quality-conscious scheduling strategies for archive crawling. Our framework includes single-visit and visit?Crevisit crawls. Single-visit crawls download every page of a site exactly once in an order that aims to minimize the ??blur?? in capturing the site. Visit?Crevisit strategies revisit pages after their initial downloads to check for intermediate changes. The revisiting order aims to maximize the ??coherence?? of the site capture(number pages that did not change during the capture). The quality notions of blur and coherence are formalized in the paper. Blur is a stochastic notion that reflects the expected number of page changes that a time-travel access to a site capture would accidentally see, instead of the ideal view of a instantaneously captured, ??sharp?? site. Coherence is a deterministic quality measure that counts the number of unchanged and thus coherently captured pages in a site snapshot. Strategies that aim to either minimize blur or maximize coherence are based on prior knowledge of or predictions for the change rates of individual pages. Our framework includes fairly accurate classifiers for change predictions. All strategies are fully implemented in a testbed and shown to be effective by experiments with both synthetically generated sites and a periodic crawl series for different Web sites.     

On some weight functions admitting (0, 2) quadrature formulae with a high algebraic degree of precision

The purpose of this paper is to find a class of weight functions μ for which there exist quadrature formulae of the form (1) $$\int_{ - 1}^1 {\mu (x) f(x) dx \approx \sum\limits_{k = 1}^n {(a_k f(x_k ) + b_k f''(x_k ))} }$$ , which are precise for every polynomial of degree 2n.     

Synthesis and structure of large single crystalline silver hexagonal microplates suitable for micromachining

We report a simple one-step synthesis method of large single crystalline Ag (111) hexagonal microplates with sharp edges and a size of up to tens of microns. Single silver crystals were produced by reduction silver nitrate aqueous solution with 4-(methylamino)phenol sulfate. Scanning and transmission electron microscopy, energy-dispersive X-ray spectroscopy, selected area electron diffraction and optical microscopy techniques were combined to characterize the crystals. It is shown that the microplates can be easily dispersed and transferred as single objects onto different substrates and subsequently used as a high quality plasmonic starting material for micromachining of future nanocomponents, using modern top-down techniques like focused-ion beam milling and gas injection deposition.     

Evaluation of surface/interface quality,microstructure and mechanical properties of hybrid additive-subtractive aluminium parts

A disadvantage of selective laser melting (SLM) processes for the manufacture of large parts is their slow build time per unit volume. A hybrid route is to generate core simple shapes traditionally, for example by machining, followed by adding final features by SLM. Here the mechanical integrity of such hybrid parts is studied, choosing the building of AlSi10Mg by SLM on a machined AA6082 base, in the shape of a tensile test piece, as a simple example. These materials are chosen for their relevance to lightweight parts. As-built parts fail at the SLM/machined interface but standard heat treatments transfer failures to the machined material. Optimised SLM processing conditions and microstructures of the SLM and interfacial regions are reported.     

Heat Inputs to Sub-mK Temperature Cryostats and Experiments from γ-Radiation and Cosmic Ray Muons

We measured the spectrum of energies deposited by -radiation, emanating from radioactive materials in the laboratory that houses our mK cryostat, and by cosmic ray muons. This allows us to quantify the heat input that adversely affects the lowest temperature accessible in sub-mK experiments. We use our nuclear stage, stage plate and experimental cell as a prototype model system, and calculate the power deposited due to low energy (below 2.65 MeV) background radiation quanta (~20 pW). This is significantly less than the power (~120 pW) deposited in the nuclear and experimental stages by muons. Installation of a 5 cm thick lead wall around the cryostat reduced the energy due to the flux of quanta by a factor of ~10 to ~2 pW, and the number of quanta by a factor of ~20. The lower energy, soft cosmic ray component was also affected by introducing the same thickness of lead, reducing the overall count of cosmic ray derived particles by ~15% and the heat leak to ~100 pW.     

The 1.5-GeV electron synchrotron in tomsk polytechnic institute

A 1.5-Gev electron synchrotron is described. The synchrotron is of the weakfocusing type with a magnetic-field fall-off index of n= 0 58 The machine operates under pulse conditions, with a repetition frequency of 1 cps. The injector is a 5.5-MeV mierotron. A voltage of 240 kV is required to accelerate electrons to 1.5 GeV, and this is designed to be supplied by two resonators. An energy of 1.1 GeV and an acceleratedbeam intensity of 1.2·10¹⁰ particles per pulse was obtained in 1965 on a synchrotron with one resonator.Translated from Atomnaya Énergiya, Vol. 21, No. 6, pp. 435–439, December, 1966.     

Tandem Accelerator with Vacuum Insulation for Boron-Neutron-Capture Therapy and Detection of Explosives by Resonance Absorption of γ-Rays

The status of the design work on an electrostatic tandem-accelerator with vacuum insulation for 2.5 MeV protons and up to 40 mA constant current is reported. This machine is to be used for solving problems of neutron therapy and the detection of explosives by nuclear-resonance absorption of -rays.     

绿色能源与绿色工业(英文)

<正>A New AUsing the Modified Four Point Probe (Mo4PP) as a Tool for Monitoring Processing of Solar Cell Wafers 1 Modified Four Point Probe The aim of this report is to present and justify a new tool (Mo4PP) for Monitoring processing of solar cells.