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91.
Versatile optimization of the synthesis method and composition of Yb3+ and Tm3+ co-doped CaF2 nanoparticles as well as a novel biofunctionalization method were developed and evaluated.Through multistep synthesis,the luminescence intensity of the Tm3+ activator was enhanced by more than 10-fold compared to standard one-step synthesis.The proposed methods were used to homogenously distribute the doping ions within the nanoparticle's volume and thus reduce luminescence quenching.Optimization of dopant ions concentration led to the selection of the most efficient visible and near-infrared up-converting nanoparticles,which were CaF2 doped with 10% Yb3+ 0.05% Tm3+ and 20% Yb3+ 0.5% Tm3+,respectively.To illustrate the suitability of the synthesized nanoparticles as bio-labels,a dedicated biofunctionalization method was used,and the nanoparticles were applied for labeling and imaging of Candida albicans cells.This method shows great promise because of extremely low background and high specificity because of the presence of the attached molecules.  相似文献   
92.
Sobieski  W  Grygo  D  Lipiński  S 《Sadhana》2016,41(11):1333-1347
Sādhanā - This paper presents the results of experimental research of the phenomena occurring in water ram during a single cycle of its operation. Apart from a brief introduction and...  相似文献   
93.
The fatigue property of an asphalt mix is an important issue in pavement design. This property is often determined with the aid of a four-point bending (4PB) test in controlled deflection mode. The fatigue property is related to the decrease in the calculated complex stiffness modulus, however, due to the non- homogenous stress and strain field in the beam, the measured response does not represent the stiffness modulus of the material but a weighted stiffness value. For a correct interpretation, a fatigue damage material model like the Asphalt Concrete Pavement-Fatigue model is needed. After integration, the calculated and measured responses are compared. By varying the model parameters, an excellent comparison between the two responses is obtained up to a certain number of cycles. This number of cycles is denoted as the fatigue life N PH . The accumulated dissipated energy at the surface of the beam in the midsection can be expressed as a constant times the fatigue life N PH to the power z and also as a constant times the product of the fatigue life N PH and the initial dissipated energy in the first cycle. Using these two findings, a Wöhler curve was established similar to the one directly based on the strain amplitudes and fatigue life data.  相似文献   
94.
Textile Reinforced Mortar (TRM), also known as Fabric Reinforced Mortar or Fabric Reinforced Cementitious Matrix, composites are an emerging technology for the external repair and strengthening of existing structures. For most applications, the effectiveness of the TRM reinforcement relies on its bond performance. This recommendation identifies the best practice to characterize the bond behaviour of TRM. A shear bond test method is proposed to determine the peak axial stress (associated with the maximum load that can be transferred from the structural member to the externally bonded TRM reinforcement), the stress–slip relationship and the failure mode that controls the TRM-to-substrate load transfer capacity. Guidelines on specimen manufacturing, experimental setup, test execution, and determination of test results are provided.  相似文献   
95.
In metastatic breast cancer the goal to reach must be the best possible palliation with minimum discomfort for the patient. We reviewed our experience with radiotherapy (20 or 30 Gy), systemic therapy and brace. Among 2200 breast cancer patients, we extracted 28 potential candidates for resection. All of them developed new metastases outside the treated field within one year. Local control was achieved in 68%, and 80% of them had stable or better performance status at 3 months. From our analysis, even patients with a so called "solitary lesion" do not seem to have a better prognosis than others. We conclude that radiotherapy (with systemic therapy and a brace) is still first-choice treatment for vertebral metastases; CT-guided percutaneous biopsy can avoid worthless major operations. The role of surgery should be limited to neurological compression, severe mechanical instability and to salvage the failures of conservative treatment.  相似文献   
96.
97.
Cellular decomposition in three Fe-26Ni-(2-3)Ti-Nb type steels was investigated. One of these steels was alloyed with molybdenum while the two others, differing in grain size, contained an addition of aluminium. In Ni26AITi3Nb and Ni26MoTi2Nb steels quenched from 1223 K in water, the first colonies of decomposition were observed after holding for 4 h at 923 K. A longer holding at this temperature resulted in growth of decomposition cells in the steel with molybdenum while in the steels with aluminium, a halting of the decomposition and the appearance of isolated plates of the phase was observed. In Ni26MoTi2Nb and Ni26Al2Ti3Nb steels, quenched in water and subsequently cold treated in liquid nitrogen, repeated heating in the temperature range 293–999.9 K at a rate of 2.5,10 and 40 Kmin–1 and cooling at a rate 320 Kmin–1 favoured the cellular decomposition more markedly in the steel with molybdenum. On cooling to room temperature, austenite within the decomposition cells transformed into martensite. The tendency to cellular decomposition depended to a higher degree on the factors which stabilize austenite as well as on the presence of precipitates in grain boundaries, than on the grain size.  相似文献   
98.
The orbito-frontal cortex and postcommissural MFB lesions evoked two major effects. The first one consisted in an increased need for light stimulation while the second one concerned changes in anxiety level with different results depending on the lesion location (cortical ot subcortical). The second effect is in agreement with P. Simonov's hypothesis concerning the different configurations of the CNS structures. Upon destruction of the orbito-frontal area, the dominant role in behaviour regulation is taken over by the "emotional part" of the brain, whereas the destruction of the postcommissural MFB (reduction of the amygdalar influence on the hypothalamus) creates conditions for functional prevalence of the "informational brain".  相似文献   
99.
The problem of computing the chromatic number of a P 5-free graph (a graph which contains no path on 5 vertices as an induced subgraph) is known to be NP-hard. However, we show that for every fixed integer k, there exists a polynomial-time algorithm determining whether or not a P 5-free graph admits a k-coloring, and finding one, if it does.  相似文献   
100.
In this paper we present a new parallel multi-frontal direct solver, dedicated for the hp Finite Element Method (hp-FEM). The self-adaptive hp-FEM generates in a fully automatic mode, a sequence of hp-meshes delivering exponential convergence of the error with respect to the number of degrees of freedom (d.o.f.) as well as the CPU time, by performing a sequence of hp refinements starting from an arbitrary initial mesh. The solver constructs an initial elimination tree for an arbitrary initial mesh, and expands the elimination tree each time the mesh is refined. This allows us to keep track of the order of elimination for the solver. The solver also minimizes the memory usage, by de-allocating partial LU factorizations computed during the elimination stage of the solver, and recomputes them for the backward substitution stage, by utilizing only about 10% of the computational time necessary for the original computations. The solver has been tested on 3D Direct Current (DC) borehole resistivity measurement simulations problems. We measure the execution time and memory usage of the solver over a large regular mesh with 1.5 million degrees of freedom as well as on the highly non-regular mesh, generated by the self-adaptive hphp-FEM, with finite elements of various sizes and polynomial orders of approximation varying from p=1p=1 to p=9p=9. From the presented experiments it follows that the parallel solver scales well up to the maximum number of utilized processors. The limit for the solver scalability is the maximum sequential part of the algorithm: the computations of the partial LU factorizations over the longest path, coming from the root of the elimination tree down to the deepest leaf.  相似文献   
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