共查询到20条相似文献,搜索用时 31 毫秒
1.
Becker S Maissen O Ponomarev I Stoll T Meury T Sprecher C Alini M Wilke I 《Journal of materials science. Materials in medicine》2008,19(2):659-665
We investigated the osteopromotive properties of plasmatransglutaminase (F XIII), bone marrow and venous blood on a resorbable
β-tricalcium phosphate (β-TCP) scaffold. A baseline binding and release study of F XIII from the scaffold showed a continuous
release of 18% of the total dose after 48 h. The main study consisted of 18 adult sheep with cylindrical defects in both tibiae.
The defects were filled with a β-TCP cylinder impregnated either with bone marrow, venous blood, F XIII or sheep were treated
with 1250 IU F XIII intravenously over 14 days (n = 4 in each group). The defects were left open in two sheep. QCT and histology was performed after 6 and 12 weeks. The best
bone ingrowth was seen after 6 weeks in the bone marrow group and after 12 weeks in the local F XIII group. The highest ingrowth
on the inside of the cylinder proving the osteopromoting potential of F XIII was found in the local F XIII group. In our opinion
F XIII is a good and readily available osteopromoting agent which can be used with β-TCP in cases of bone deficit to promote
bone regeneration. 相似文献
2.
J. Cuppens G. W. Ataklti W. Gillijns J. Van de Vondel V. V. Moshchalkov A. V. Silhanek 《Journal of Superconductivity and Novel Magnetism》2011,24(1-2):7-11
The vortex dynamics in a superconducting thin Al film with a periodic Honeycomb or Kagome array of antidots has been investigated by electrical transport measurements. The large values of the superconducting coherence length and penetration depth of the Al films guarantee a maximum of one flux quantum trapped per pinning site. This allows us to directly compare the experimental results with previous theoretical investigations based on molecular dynamics simulations. For the Kagome lattice, two submatching features not anticipated theoretically at H/H 1=1/3 and 2/3, where H 1 is the field at which the number of vortices coincides with the number of pinning sites, are observed. Possible corresponding stable vortex patterns are suggested. For the Honeycomb pinning landscape, the commensurability effects are in agreement with the theoretical expectations. A preliminary analysis of the vortex mobility in this lattice shows the presence of a weak vortex guidance. 相似文献
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ZHAOHong XIAYong LIANGXiao-guo 《国际设备工程与管理》2003,8(2):65-73
For the first fime,the diagnosis idea based on a correlation integral is proposed,which re-gards the correlation integral as a feature set.The correlation dimension is contained in the double-log curve of the correlation integral to scale,so extracting features directly from the correlation integral can avoid the bottleneck problem of determining the range of non-scale length.Several features extracted from the correlation integral are better than the single feature of the correlation dimension when descri-bing the signal.It is obvious that this method utilizes more information of the signal than does the cor-relation dimension.The diagnosis examples verify that this method is more accurate and more effective. 相似文献
4.
Andrew Lahy Ai Qiang Li Pauline Found Aris Syntetos Mike Wilson Nicole Ayiomamitou 《国际生产研究杂志》2018,56(6):2233-2249
A Product–Service System (PSS) is created by combing a tangible product and an intangible service into one integrated offering. Thus, a PSS can be achieved by a production company adding intangible services to a product using a servitisation strategy or by a service company adding a tangible product to a service by means of a productisation strategy. The focus of this paper is on the latter. Our work demonstrates a significant gap in the literature in this area. To address this, we adapt an existing PSS conceptual framework as a means to identify the driving and restraining forces considered by a service company as it explored the possibility of pursuing a PSS productisation strategy. The conceptual framework is applied in an exploratory case study with a 3PL service provider. Application of the framework reveals new driving and restraining forces not previously discussed in the literature. Furthermore, it allows a preliminary quantification of the driving and restraining forces using a force field analysis approach. Our work contributes towards the expansion of the empirical knowledge base in the area of PSS. 相似文献
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LUO You-xin CAI An-hui ZHANG Long-ting GUO Hui-xin Department of Mechanical Engineering Changde Normal College Changde P. R. China 《国际设备工程与管理》2001,6(2)
1 IntroductionReiability acted as an imPortant index that was aPPied to weigh the quality of a mechanicalProdct, and it has brOadiy been thought. Currently, an imPortant taSk of machine scope is to aimat the market's needs inside and outside the country and adust the strUcture of ProductS tooccuPy the Inarket in Products of high qualiy It is a key aspeCt of all tO sahsfy reiability needsof users in the new Products explored. The machine transAnssion system is an imPortantcomPosition of… 相似文献
7.
The objective of the present work was to systematically investigate the issue of minimum cement content requirements, by studying
the behavior of concretes with different water to cement ratios (
w/c) in the range of 0.45–0.70, in which the cement content was varied, by controlling the water content, using water reducing
admixtures. The effect of cement content was noted to be different for various properties: strength was a function of w/c and independent of cement content; total water absorption was proportional to the paste content at a given w/c, while capillary absorption and chloride ingress reduced with a reduction in the cement content for a given w/c, to an extent which was much greater than the reduction in total porosity. Carbonation and shrinkage were largely independent
of cement content for a given w/c. The trends observed were discussed in terms of the effect of paste content on concrete properties, and the influence of
admixtures on the paste properties. These results suggest that requirements for minimum cement content in standards should
be revisited. 相似文献
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Ganji MD 《Nanotechnology》2008,19(2):025709
Density functional theory (DFT) is used to investigate the adsorption properties of nitrogen on the pentagon at the tip of a capped (5, 5) single-walled carbon nanotube. The adsorption of N(2) outside the carbon nanotube with a parallel orientation with respect to the plane of the pentagon is found to be the most stable state of adsorption. Its binding energy of -0.318?eV is very small, with a large C-N equilibrium distance of 2.94??. We have also investigated the number and the position of adsorption sites in the pentagon for the parallel configuration. This knowledge can lead to the precise control of adsorption states, and consequently may bring about a novel multistate monomolecular device. We find two stable configurations of the molecule that have only a small difference in energy, while the other configurations are energetically unfavorable. Our results support previous experimental predictions that the nitrogen molecule transits between two states with a small current pulse. The predicted position sites for the transient states are in reasonable agreement with experimental observations. 相似文献
10.
Sandeep Gorantla Stanislav Avdoshenko Felix Börrnert Alicja Bachmatiuk Maria Dimitrakopoulou Franziska Schäffel Ronny Schönfelder Jürgen Thomas Thomas Gemming Jamie H. Warner Gianaurelio Cuniberti Jürgen Eckert Bernd Büchner Mark H. Rümmeli 《Nano Research》2010,3(2):92-97
In situ low-voltage aberration corrected transmission electron microscopy (TEM) observations of the dynamic entrapment of a C60 molecule in the saddle of a bent double-walled carbon nanotube is presented. The fullerene interaction is non-covalent, suggesting that enhanced π-π interactions (van der Waals forces) are responsible. Classical molecular dynamics calculations confirm that the increased interaction area associated with a buckle is sufficient to trap a fullerene. Moreover, they show hopping behavior in agreement with our experimental observations. Our findings further our understanding of carbon nanostructure interactions, which are important in the rapidly developing field of low-voltage aberration corrected TEM and nano-carbon device fabrication. 相似文献
11.
《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1988,265(3):419-434
Results from a test with a lead-copper calorimeter in liquid argon are presented. The electromagnetic energy resolution obtained is 10%/√E. For hadronic showers the software weighting technique is demonstrated to work. A hadronic energy resolution of 50%/√E is found. 相似文献
12.
By combining the artificial neural network with the rule reasoning expert system,an expert diagnosing system for a rotation mechanism was established.This expert system takes advantage of both a neural network and a rule reasoning expert system;it can also make use of all kinds of knowledge in the repository to diagnose the fault with the positive and negative mixing reasoning mode.The binary system was adopted to denote all kinds of fault in a rotation mechanism.The neural networks were trained with a random parallel algorithm (Alopex).The expert system overcomes the self-learning difficulty of the rule reasoning expert system and the shortcoming of poor system control of the neural network.The expert system developed in this paper has power ful diagnosing ability. 相似文献
13.
LUYong-zhong 《国际设备工程与管理》2004,9(1):11-19
A dynamic model of a flexible rotor-sliding bearing system (FRSBS) with a squeeze film damper (SFD) is established. Considered in the model are oil film inertia force, damping force,clearance excitation force, interference force of different frequencies and static load, as opposed to previous research. On the basis of this model, the optimal design of the system is deeply studied. Simulation shows that the system optimization design can effectively improve the system stability. 相似文献
14.
本文用MH81方程计算了R152a/R134a在243.15K ̄313.15K范围内的等温汽液相平衡。计算表明:R152a/R134a是共沸混合物,有一最低共沸点。 相似文献
15.
The behavior of dynamic emission of dislocations from the tip of a stationary crack under mode II or mode III loading is examined. A critical stress intensity factor, K
D is assumed for dislocation emission. After emission, the dislocation moves with a velocity which varies with the effective shear stress to the third power. The effective shear stress is due to the applied stress , modified by the presence of the crack and all other dislocations minus the lattice friction stress, F. The effects of K
D, , and F on the rate of emission, the plastic zone strain rate, the plastic zone size, the dislocation distribution, and the dislocation-free zone are reported.
Résumé On a examiné le comportement d'une émission dynamique de dislocations depuis l'extrémité d'une fissure stationnaire. On suppose que l'émission de dislocations est caractérisée par un facteur critique d'intensité de constrainte K D. Après son émission, la dislocation se meut avec une vitesse qui varie avec le cube de la constrainte effective de cisaillement. Celle-ci résulte de la constrainte appliquée , modifiée par la présence de la fissure et de toutes les autres dislocations, et sous déduction de la contrainte de friction du réseau, F.On étudie les effects de K D, et F sur la vitesse d'émission des dislocations, la vitesse de déformation plastique, la taille de la zone plastique, la distribution des dislocations, et sur la zone qui en est dépourvue.相似文献
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S. V. Fedorov A. V. Babkin S. V. Demidkov 《Journal of Engineering Physics and Thermophysics》2000,73(6):1226-1235
We consider the possibility of enhancement of a magnetic field created in a conducting medium on penetration into it of a highvelocity striker moving across the magneticinduction lines. For the case of a perfectly conducting target, an estimate is obtained for the rate of increase of the field intensity in the region of contact with the head part of the striker. A dimensionless parameter is introduced that characterizes the relationship between the rates of generation and diffusion of the field on penetration into a material of finite conductivity. Based on a model that takes into account the force action of a compressed field, the special features of the flow that arises on penetration of a highvelocity cumulative jet into a perfectly conducting target with a transverse magnetic field are analyzed. 相似文献
19.
I. T. Denisyuk 《Journal of Engineering Physics and Thermophysics》2003,76(6):1394-1395
Thermal conductivity of a threedimensional body with a rough inclusion is studied. The problem is reduced to the problem of conjugation of harmonic functions and its exact solution is constructed. Distributions of temperature and heatflux density near distinctions of the interface between media are found. Results are illustrated by a numerical example. 相似文献
20.
High Temperature - Based on previous experimental studies, we carried out a numerical simulation of the process of the critical outflow of a vapor–liquid flow in cylindrical channels filled... 相似文献