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61.
NaSICON-type lithium conductor Li1.3Al0.3Ti1.7(PO4)3 (LATP) is synthesized with controlled grain size and composition using solution chemistry. After thermal treatment at 850 °C, sub-micronic crystallized powders with high purity are obtained. They are converted into ceramic through Spark Plasma Sintering at 850–1000 °C. By varying the processing parameters, pellet with conductivities up to 1.6 × 10?4 S/cm with density of 97% of the theoretical density have been obtained. XRD, FEG-SEM, ac-impedance and Vickers indentation were used to characterize the products. The influence of sintering parameters on pellet composition, microstructure and conductivity is discussed in addition to the analysis of the mechanical behavior of the grains interfaces.  相似文献   
62.
Polymethyl methacrylate (PMMA)/Fe(IO3)3 nanocomposite thin films are obtained by in situ particle generation in microemulsions and subsequent photopolymerization of a mixture containing methyl methacrylate, trimethylolpropane triacrylate, and crystallized iron iodate (Fe(IO3)3) nanorods. Hyper‐Rayleigh scattering measurements combined with X‐ray diffraction, transmission electron microscopy, and dynamic light scattering are first used to probe in situ the crystallization kinetics of iron iodate nanorods in water‐in‐oil microemulsions prepared with methyl methacrylate as the oil phase and marlophen NP12 as a surfactant. Trimethylolpropane triacrylate is then added as a crosslinker before spin‐coating. Films are deposited on glass substrates for the nonlinear optical characterizations and on silicon wafers for the piezoelectric and mechanical measurements. Nanocomposite films treated by corona discharge are finally characterized through optical microscopy, laser Doppler vibrometry, and Brillouin spectroscopy. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1203‐1211, 2013  相似文献   
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Rock matrix stimulation is a method of enhancing well production or injection within a broad range of challenging environments, varying from naturally fractured limestones to sandstones with complex mineralogy. A common and often successful stimulation option, matrix acidizing, utilizes acids that react and remove mineral phases restricting fluid flow. Reviewed is the technology of chemical treatments available for oil, gas and geothermal wells and the key elements and results of the chemical reservoir stimulation program at the Soultz-sous-Forêts, France, Enhanced Geothermal System Project.  相似文献   
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High-dose chemotherapy followed by autologous peripheral blood progenitor cell transplantation (PBPCT) is increasingly applied in patients with relapsed, poor risk malignant lymphomas. Different strategies for progenitor cell mobilization using cytoreductive chemotherapy, hematopoietic growth factors, or both have been described. We studied the safety and efficacy of a modified DexaBEAM regimen (dexamethasone, BCNU [carmustine], etoposide, ara-C, melphalan) followed by granulocyte-colony stimulating factor (G-CSF) that was administered in order to minimize any residual disease and to obtain a sufficient amount of progenitor cells in the autografts. Until now, 16 patients at poor risk (8 with Hodgkin's disease, 8 with non-Hodgkin's lymphoma) entered the study. All the 12 patients with measurable disease at study entry responded to DexaBEAM. Median time of subsequent leukopenia (leukocytes < 1.000/microL) was 6 days (range 5-8 days). Peak numbers of CD34+ hematopoietic progenitor cells appeared in the peripheral blood after a median of 20 days (range 18-22 days) after onset of therapy. At that time, peripheral mononuclear cells were collected for autografting. Thereafter, the leukapheresis products were frozen until the day of transplantation, either unpurged in the case of Hodgkin's disease or purged with the ether lipid edelfosine in cases of non-Hodgkin's lymphoma. After high-dose chemotherapy with the CBV regimen (cyclophosphamide, BCNU, etoposide) the patients received their autografts, followed again by G-CSF treatment. A stable hematopoietic recovery was reached with granulocytes > 2.000/muL within 11 days (range 8-17 days), and platelets > 50.000/microL within 15 days (range 10-31 days), respectively, without significant differences between the purged and unpurged transplants. After a median follow-up of 28 months (range 1-40 months) 7 patients are alive without signs of recurrent disease, while 1 patient has died due to acute treatment related toxicity. Three patients had refractory disease, and 5 have relapsed of whom 4 have died. In summary, the DexaBEAM/G-CSF/CBV strategy appears to be safe and effective for salvage treatment in patients with poor risk malignant lymphomas.  相似文献   
67.
The thermoreversible gelation of poly[hexyl isocyanate] (PHIC), a rather stiff polymer, has been studied in two closely-related solvents of the alcane series, namely heptane and octane. Temperature-concentrations phase diagrams have been established for both systems. The occurrence of polymer-solvent compound is suggested in heptane but not in octane. This conclusion receives further support from neutron diffraction investigations through the use of the isotopic labelling technique. Finally, it is observed that the morphology is also affected by the solvent type although still displaying a fibrillar network structure.  相似文献   
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69.
Plasma Levels and Apparent Digestibility of α-Tocopherol as Related to Vitamin E Supplementation in Early-Weaned Piglets Piglets weaned at 21 d of age were fed a complete ration containing 16 I.U. vitamin E/kg (treatment I) according to NRC (1988) or supplemented with 45 mg or 225 mg α-tocopheryl acetate/kg (treatments II and III). Concentrations of α-tocopherol (AT) in plasma were measured until day 14. In weeks 5 and 7, the apparent digestibility of AT, total lipids and organic matter was analysed using chromic oxide as a marker. In treatment I, plasma AT concentration decreased with a mean half-life of 11.4 d. In week 5, the apparent digestibility of AT was 17.3%, 23.6% and 17.1% in treatments I to III, respectively. In week 7, it was unchanged in treatment I, while it was significantly higher (p<0.05) in treatments II and III (46.6% and 55.4%). No age-dependent differences were found in the apparent digestibility of total lipids and organic matter.  相似文献   
70.
Monitoring the evolution of an early age set of parameters on concrete is necessary to predict the early age behaviour of structures. The difficulty lies in the fact that this monitoring must be automatic because the concrete hardening process takes place over a long period after the casting. This paper presents a new methodology and an apparatus, specifically designed at IFSTTAR, to monitor the hardening process of a concrete. Mainly, the Young’s modulus can be monitored in compression. Measurements start soon after having cast the concrete and the sample temperature is completely controlled so that the concrete maturity is well mastered. The performances of this apparatus, obtained on an ordinary concrete, are compared to more classical measurements using an extensometer mounted on the sample just after the setting time and to ultrasonic measurements. In these cases, the temperatures were not controlled and results have to be expressed in equivalent time. A comparison with another method developed and used at ULB by using the same concrete, in the frame of a joined cooperation between our two laboratories is achieved. This test set up is based on the so called Temperature Stress Testing Machine (TSTM). This device has been specifically designed with a control of the concrete maturity by the use of a dummy specimen only submitted to free deformations (thermal, shrinkage). The TSTM allows compressive and tensile testing starting just after the setting time. In addition, concrete properties, such as compressive and tensile strength, have been characterized at early age. These values have been used for the design of the loading histories applied in the automatic tests. The heat released by the cement hydration has also been measured in order to express the results on a maturity scale.  相似文献   
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