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1.
The main drawback of bioglasses is their restricted use in load bearing applications and the consequent need to develop stronger glassy materials. This has led to the consideration of oxynitride glasses for numerous biomedical applications. This paper investigated two different types of glasses at a constant cationic ratio, with and without nitrogen (a N containing and a N-free glass composition) to better understand the effect of N on the biological properties of glasses. The results revealed that the addition of N increased the glass transition temperature, isoelectric point (IEP) and slightly increased wettability. Moreover, compared to N including glass, N-free glass exhibited better anti-bacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), two key bacteria that infect implants. In summary, these in vitro results indicated that amine functional groups existing in N containing glasses which are missing in N-free glasses, caused a slight difference in wetting behavior and a more obvious change in isoelectric point and in bacterial response. N-free glasses exhibited better inhibitory results both against E. coli and S. aureus compared to N including glass suggesting that oxygen rich glasses should be further studied for their novel antibacterial properties.  相似文献   
2.
A patient with B-cell prolymphocytic leukemia (PLL) who has had a prolonged survival is presented. The patient was diagnosed incidentally while asymptomatic, but later developed progressive disease. He was refractory to alkylating agents and fludarabine, but responded to treatment with cyclophosphamide, doxorubicin, vincristine, and prednisone. This patient's prolonged survival may be due partly to his diagnosis at an indolent phase, possibly representing the early phase of the natural course of the disease. Diagnosis, clinical course, and treatment options for PLL are discussed.  相似文献   
3.
Subsurface Characterization at Ground Failure Sites in Adapazari, Turkey   总被引:4,自引:0,他引:4  
Ground failure in Adapazari, Turkey during the 1999 Kocaeli earthquake was severe. Hundreds of structures settled, slid, tilted, and collapsed due in part to liquefaction and ground softening. Ground failure was more severe adjacent to and under buildings. The soils that led to severe building damage were generally low plasticity silts. In this paper, the results of a comprehensive investigation of the soils of Adapazari, which included cone penetration test (CPT) profiles followed by borings with standard penetration tests (SPTs) and soil index tests, are presented. The effects of subsurface conditions on the occurrence of ground failure and its resulting effect on building performance are explored through representative case histories. CPT- and SPT-based liquefaction triggering procedures adequately identified soils that liquefied if the clay-size criterion of the Chinese criteria was disregarded. The CPT was able to identify thin seams of loose liquefiable silt, and the SPT (with retrieved samples) allowed for reliable evaluation of the liquefaction susceptibility of fine-grained soils. A well-documented database of in situ and index testing is now available for incorporating in future CPT- and SPT-based liquefaction triggering correlations.  相似文献   
4.
YbBa2Cu3O7?x (YbBCO) thick films were grown on buffered, cube-textured Nickel tapes by sol–gel dip-coating method. Yb-123 films were prepared using solutions of Yb, Ba, and Cu organometallic compounds. A solution-based Gd2O3 buffer layer was deposited by dip-coating process with excellent texture and uniformity. The texture development and surface morphology of the buffer-layer films were examined by X-ray diffraction, pole figures, and ESEM analysis. Microstructure and characterization of Yb-123 films were done by ESEM, EDS, and XRD analysis. T c and J c were conducted by four-wire measurement method  相似文献   
5.
The maximization of the total surface area of Pt-SnO2/Al2O3 catalyst was studied by using the Taguchi method of experimental design. The catalysts were prepared by sol-gel method. The effects of HNO3, H2O and aluminum nitrate concentrations and the stirring rate on the total surface area were studied at three levels of each. L9 orthogonal array leading nine experiments was used in the experimental design. The parameter levels that give maximum total surface area were determined and experimentally verified. In the range of conditions studied it was found that, medium levels of HNO3 and H2O concentration and lower levels of aluminum nitrate concentration and stirring rate maximize the total surface area.  相似文献   
6.
Bilal Alatas  Erhan Akin   《Knowledge》2009,22(6):455-460
In this paper, classification rule mining which is one of the most studied tasks in data mining community has been modeled as a multi-objective optimization problem with predictive accuracy and comprehensibility objectives. A multi-objective chaotic particle swarm optimization (PSO) method has been introduced as a search strategy to mine classification rules within datasets. The used extension to PSO uses similarity measure for neighborhood and far-neighborhood search to store the global best particles found in multi-objective manner. For the bi-objective problem of rule mining of high accuracy/comprehensibility, the multi-objective approach is intended to allow the PSO algorithm to return an approximation to the upper accuracy/comprehensibility border, containing solutions that are spread across the border. The experimental results show the efficiency of the algorithm.  相似文献   
7.
CO2 injection into deep saline aquifers is a preferred method for mitigating CO2 emission. Although deep saline aquifers are found in many sedimentary basins and provide very large storage capacities, several numerical simulations are needed before injection to determine the storage capacity of an aquifer. Since numerical simulations are expensive and time-consuming, using a predictive model enables quick estimation of CO2 storage capacity of a deep saline aquifer. In order to create a predictive model, the ranges of variables that affect the CO2 storage capacity were determined from published literature data. Correlations found in literature were used for other important parameters such as pore volume compressibility and density of brine. Latin hypercube space filling design was used to construct 100 simulation cases prepared using CMG STARS. The simulation period covered a total of 300 years of CO2 storage. By using a least-squares method, linear and nonlinear predictive models were developed to estimate CO2 storage capacity of deep saline carbonate aquifers. Numerical dispersion effects were considered by decreasing the grid dimensions. It was observed that a dimensionless linear predictive model is better than the nonlinear. The sensitivity analyses showed that the most important parameter that affects CO2 storage capacity is depth. Most of the (up to 90%) injected gas dissolved into the formation water and a negligible amount of CO2 reacted with carbonate.  相似文献   
8.
This paper discusses the implementation of a low-cost 128 times 128 uncooled infrared microbolometer detector array together with its integrated readout circuit (ROC) using a standard 0.35 mum n-well CMOS and post-CMOS MEMS processes. The detector array can be created with simple bulk-micromachining processes after the CMOS fabrication, without the need for any complicated lithography or deposition steps. The array detectors are based on suspended p+-active/n-well diode microbolometers with a pixel size of 40 mum times 40 mum and a fill factor of 44%. The p+-active/n-well diode detector has a measured dc responsivity (R) of 4970 V/W and a thermal time constant of 36 ms at 50 mtorr vacuum level. The total measured rms noise of the diode type detector is 0.69 muV for an 8 kHz bandwidth, resulting in a detectivity (D*) of 9.7 times 108 cm ldr Hz1/2/W. The array is scanned by an integrated 32-channel parallel ROC including low-noise differential preamplifiers with an electrical bandwidth of 8 kHz. The 128 times 128 focal plane array (FPA) has one row of infrared-blind reference detectors that reduces the effect of FPA fixed pattern noise and variations in the operating temperature relaxing the requirements for the temperature stabilization. Including the noise of the reference and array detectors together with the ROC noise, the fabricated 128 times 128 FPA has an expected noise equivalent temperature difference (NETD) value of 1 K for f/1 optics at 30 frames/s (fps) scanning rate. This NETD value can be decreased to 350 mK by improving the post-CMOS fabrication steps and increasing the number of readout channels.  相似文献   
9.
Four different types of high-density polyethylenes were blended with expanded perlite at different compositions. -aminopropyltriethoxysilane was applied to perlite (2 wt%) from ether and water solutions to enhance the interfacial adhesion between the polymer and the filler. It was shown that silane treatment advances the yield stress with improving dispersion and increasing the interfacial adhesion of the filler with the polymer matrix. The experimental results were then checked with the expression of Turcsanyiet al.'s.  相似文献   
10.
Protection of Metals and Physical Chemistry of Surfaces - Corrosion inhibition effects of water-soluble peripheral substituted cobalt, copper and zinc metallophthalocyanines (CoPc (1), CuPc (2) and...  相似文献   
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