ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Articles  (46)
  • Technology  (46)
Collection
  • Articles  (46)
Source
Keywords
Publisher
Years
Journal
Topic
  • 1
    Electronic Resource
    Electronic Resource
    Effect of Micro-Voids on Plasticity in NiTi-Alloys (2008)
    s.l. ; Stafa-Zurich, Switzerland
    Advances in science and technology Vol. 59 (Sept. 2008), p. 135-139 
    Details
    ISSN: 1662-0356
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Natural Sciences in General , Technology
    Notes: Recent experimental investigations have indicated that commercial NiTi superelasticalloys consist of particles and inclusions which can nucleate micro-voids. Almost no study on theeffect of micro-voids has been carried out in the literature. In this study the effect of micro-voidsand plasticity on the behaviour of a superelastic NiTi-alloy has been investigated. Axisymmetricunit cell models with different micro-void volume fractions have been analysed subjected to variousstress triaxiality states. It is shown that the onset of plasticity is located at the void edge as themaximum stress initially occurs at this position. The finite element results indicate that the existenceof micro-voids can reduce the re-centring capabilities in NiTi-alloys and that this effect should betaken into consideration of constitutive equations
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/01/42/transtech_doi~10.4028%252Fwww.scientific.net%252FAST.59.135.pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Development of soluble glasses for biomedical use Part II: The biological response of human osteoblast cell lines to phosphate-based soluble glasses (2000)
    Springer
    Journal of materials science 11 (2000), S. 615-620 
    Details
    ISSN: 1573-4838
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract Soluble glasses are considered to be of potential clinical value in orthopaedic and dental surgery. However, the biological response to these materials is not well understood. To determine the effects of these glasses, two human osteoblast cell lines, MG63 and HOS (TE85), were incubated in vitro in the presence of increasing concentrations of extracts of the glasses. The effects of the extracts on cell growth was measured using the MTT assay and an ELISA assay was used to measure the expression of bone sialoprotein (BSP), osteonectin (ON) and fibronectin (FN), antigens which play a fundamental part in the integrity and function of hard connective tissue. The results showed that the proliferation of the cells was adversely affected only by the more soluble glasses, which also down-regulated the expression of the bone-associated proteins. In contrast, the extract of the glass with the lowest dissolution rate, which contains relatively elevated levels of Ca2+, was found to enhance bone cell growth and antigen expression. These findings suggest that the compositions of these glasses at least partly determine the response of cells and thus, that the glasses could be modified to elicit a more optimal biological response and clinical efficacy.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008901612674
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Transmission electron microscopy study of a dental gallium alloy (1996)
    Springer
    Journal of materials science 7 (1996), S. 447-455 
    Details
    ISSN: 1573-4838
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract Analytical transmission electron microscopy (TEM) studies of a dental gallium alloy have been carried out. This commercial Ga alloy was made by triturating a Ag-Sn-Cu-rich alloy powder with a liquid Ga alloy containing Ga, In and Sn. Ga alloys are of increasing interest as an alternative to amalgam. The dental material studied in the present work was found to be a composite consisting of remaining, undissolved particles from the Ag-based alloy powder in a matrix of reaction products with the liquid Ga alloy. The phases in the matrix and the remaining Ag-based alloy particles have been identified by electron diffraction, high resolution electron microscopy and energy dispersive X-ray spectroscopy. the following phases were identified: orthorhombic Ag3Sn, cubic γ-Cu9Ga4, cubic Ag9In4, tetragonal β-Sn and hexagonal Ag2Ga. In addition to these well-known phases Ga-rich regions of Cu-Ga were observed consisting of an intergrowth of the tetragonal CuGa2 and one of the cubic γ-Cu9Ga4 phases.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00122015
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    A descriptive multi-attribute model for reconfigurable machining system selection examining buyer-supplier relationships (2000)
    Bingley : Emerald
    International journal of agile management systems 2 (2000), S. 33-48 
    Details
    ISSN: 1465-4652
    Source: Emerald Fulltext Archive Database 1994-2005
    Topics: Technology
    Notes: Presents a model of the machining system selection process that is focused on capital intensive, complex machining systems that are intended to provide service over a long time horizon. This model was developed based on interviews with both machine tool suppliers and buyers. The systems considered here increasingly face potentially conflicting demands such as: the ability to be quickly and inexpensively upgraded and reconfigured in order to have quick new product change-over and ramp-up time; and high product variety at close to mass production costs. This new "reconfigurability" capability increases the importance of the supplier-buyer relationship after the machining system has been selected. We also remark that the selection process can serve as the basis for internal consensus and team building within the buyer firm and for enhancing supplier base quality.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1108/14654650010312598
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Measurement and imaging of supersonic combustion in a model scramjet engine (1999)
    Springer
    Shock waves 9 (1999), S. 221-226 
    Details
    ISSN: 1432-2153
    Keywords: Key words:Supersonic combustion, Shock tunnel, Shadowgraph, Flow imaging, Numerical simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics , Technology
    Notes: Abstract. Results of tests performed in a free-piston shock tunnel on a model scramjet engine are presented. Two conditions which differed in Mach number were tested. Flow at the lower Mach number condition was achieved using a variable-angle diffuser. Shadowgraph images and floor static pressure measurements were obtained, the latter used as the basis of a finite-difference calculation of flow properties in the scramjet.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001930050159
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Venous return of an artificial heart designed to prevent right heart syndrome (1974)
    Springer
    Annals of biomedical engineering 2 (1974), S. 335-342 
    Details
    ISSN: 1573-9686
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract A large number of calves maintained up to two weeks with the Kwan-Gett artificial heart have had elevated central venous pressure with associated ascites, edema, oliguria responding to diuretics, and increased body weight and weight of organs at autopsy. This has been described as right heart failure syndrome and has been a problem limiting survival with the artificial heart. The high venous pressure has been attributed to inadequate pumping characteristics of the heart as well as imperfect fit which obstructs venous return. A new design of an artificial heart was tested on the mock circulation and in one calf with encouraging results. Venous return remained unimpaired during the artificial heart test in the calf. The heart is designed with the following main characteristics. (1) Highly flexible ventricular diaphragm. (2) Low resistance to inflow. (3) Parallel disposition of artificial ventricles and artificial atria for a better anatomical relation to the natural ostia. (4) Artificial atria with air chambers vented to the atmosphere. The increased compliance of the atrial walls prevented reduction of venous return caused by vacuum applied to the ventricles during the filling period. Although the heart compromised lung space, it demonstrated the need for still another new design which will not obstruct venous return and will maintain normal venous pressures without compromising lung space.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02368093
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Microwave-induced chronotropic effects in the isolated rat heart (1977)
    Springer
    Annals of biomedical engineering 5 (1977), S. 395-409 
    Details
    ISSN: 1573-9686
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract Continuous wave (cw) microwave irradiation at 960 MHz has caused bradycardia in isolated, perfused rat hearts maintained at 20°C. The observed bradycardia occurred at microwave dose rates that should have caused mild tachycardia in the heart based on the thermogenic properties of the irradiation. The observed bradycardia, moreover, exhibited neurologic features because atropinized hearts showed strong tachycardia during irradiation and hearts treated with propranolol showed significantly stronger bradycardia during irradiation than that seen without drugs. Use of the liquid-crystal optical-fiber (LCOF) temperature probe has shown, by calorimetric methods, that the microwave-induced bradycardia occurred at dose rates of 1.3 and 2.1 mW/g. We hypothesize that microwave energy interacts with the remaining portion of the autonomic nervous system within the heart to produce the observed chronotropic effects.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02367318
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Renal cortical perfusion-Preliminary experience with the Dynamic Spatial Reconstructor (DSR) (1985)
    Springer
    Annals of biomedical engineering 13 (1985), S. 259-271 
    Details
    ISSN: 1573-9686
    Keywords: Renal cortex ; Perfusion ; X-ray ; Tomography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract The three-dimensional image data generated by the Dynamic Spatial Reconstructor (DSR) enables measurement of the three-dimensional distribution of blood supply in organs. We have applied this imaging technique to evaluate renal cortical blood flow distribution and compare it with distribution of radiolabeled microspheres. The DSR, a high temporal resolution volumetric roentgenographic computed tomographic scanner, was used to scan the volume containing a kidney in 0.13–0.26 s and repeating this scan 8–4 times per s for six s during a renal arteriogram. Five anesthetized dogs were studied in the prone position with the left kidney exteriorized through a flank incision. An electromagnetic flowmeter was placed around the renal artery and a needle placed retrograde into the artery for injection of a 2 cc bolus of contrast agent. During the scan the contrast agent was injected over a four s period during which radioactively labelled microspheres were injected into the left atrium. The tomographic images of approximately 10 parallel, 5 mm thick sagittal slices corresponding to the slices of the kidney used for counting microspheres in the cortical layers were displayed and analyzed. The time point chosen for analysis was the one in which peak brightness (i.e., concentration of contrast agent) was detected in the cortex. The spatial distribution of peak brightness values was compared to the number of microspheres at the same sampling locations. The microsphere-based value of regional cortical blood flow fell below the regression line for the juxtamedullary cortex and above for the outer cortex. This result is consistent with the preferential distribution of microspheres to the outer cortex whereas the contrast agent distributed more uniformly throughout the cortex.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00000005
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Computerized estimates of functional residual capacity in infants (1981)
    Springer
    Annals of biomedical engineering 9 (1981), S. 243-255 
    Details
    ISSN: 1573-9686
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract The methods presently available for measuring FRC of newborn infants are impractical and used primarily as research tools. This report describes a new device for estimating FRC which is accurate, reproducible, and practical for use on critically ill infants in the intensive care unit. Measurements are made using either [1] standard multiple breath N2 washout or [2] a new 4-breath N2 washout method of estimating FRC. Automating the measurements with a microcomputer reduced the time required for data reduction from 45 min to seconds. Utilizing the 4-breath method reduced measurement times (including time for reequilibration) from 15 min to less than a minute; thus, repeated measurements may be made even in critically ill infants suffering from RDS whose FRC may be relatively unstable. Breathing O2 for only 4 breaths also reduces possible damaging effects of O2 such as retinopathy and absorption atelectasis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02363458
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    A comprehensive elementary model of the mammalian circulatory system (1982)
    Springer
    Annals of biomedical engineering 10 (1982), S. 1-33 
    Details
    ISSN: 1573-9686
    Keywords: Circulatory ; Model ; Hydrodynamic ; Blood flow ; Mammalian
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract Beginning with a set of simplifying assumptions and the statements for the hydrodynamic and thermodynamic processes involved, a comprehensive mathematical model for the mammalian circulatory system is developed and evaluated. Analytical relationships are derived and examined for the circulatory component pressures, flow rates, blood volumes, flow resistances, pumping power and pumping rate. The essential circulatory model parameters are identified and inspected for their influence upon circulatory behavior. A complete and consistent set of circulatory model parameters is given for the adult human male and the model response is examined. In general, agreement of the model predictions for man with experimental data is good.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00000001
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...