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91.
Thin films of NiO were deposited on Pt/Ta/glass sub-strates using a radio frequency (RF) sputtering method. The NiO thin films showed polycrystalline nature, indicating preferentially (111)-oriented structure. The resistive random access memory (RRAM) capacitor of a Pt/NiO/Pt structure exhibited unipolar switching characteristics and bistable resistivities for 200 repeated switching cycles. Furthermore, RRAM nanobits array was formed on the NiO thin films by applying a bias. The RRAM nanobits had a diameter of approximately 8 nm and were observed via a conducting atomic force microscope (CAFM). The density of the RRAM nanobits array was estimated to be approximately 0.64 Tbit/cm2.  相似文献   
92.
OBJECTIVE: To identify factors associated with the initiation of breast-feeding in a predominantly Puerto Rican population living in inner-city Hartford, Conn. DESIGN: Retrospective study of 144 Latino women (mean +/- standard deviation age = 26.3 +/- 5.7 years) with children at least 1 year old but younger than 6 years old (mean +/- standard deviation age = 3.0 +/- 1.2 years) at the time of the survey. Women were recruited from agencies sponsoring health programs for mothers and children. They were interviewed in their homes (69%) or at the Hispanic Health Council, Hartford, Conn (31%). SUBJECTS/SETTING: Low-income Latino women who had at least 1 preschooler at the time of the interview. The women lived in inner-city Hartford, and the overwhelming majority were Puerto Rican and received welfare assistance and food stamps. Seventy-eight percent of the women chose to be interviewed in Spanish; the other 22% were interviewed in English. STATISTICAL ANALYSES: Explanatory variables that related to breast-feeding initiation (P < or = .2) in bivariate chi 2 analyses were entered into a multivariate logistic regression model that was reduced using backward stepwise elimination procedures. RESULTS: Multivariate analyses indicated that breast-feeding the previous child, shorter length of maternal residence in the United States, not receiving prenatal bottle-feeding advice, more recent birth, and higher birth weight were positively associated with breast-feeding initiation. A major reason for choosing not to breast-feed was that women felt socially uncomfortable doing it. APPLICATIONS: Breast-feeding initiation was more likely in Latino women who received prenatal breast-feeding counselling and postpartum support. Mothers of low-birth-weight infants and women breast-feeding for the first time may need additional help. These findings can be used by programs like the Special Supplemental Nutrition Program for Women, Infants, and Children to increase breast-feeding initiation.  相似文献   
93.
Nanosize cobalt oxides as anode materials for lithium-ion batteries   总被引:5,自引:0,他引:5  
Nanosize cobalt oxides (Co3O4) were synthesised by chemical decomposition of cobalt octacarbonyl in toluene at low temperature. Electrochemical properties of as-prepared Co3O4 as anodes in Li-ion cells were tested. The nanosized Co3O4 electrode demonstrate a stable reversible lithium storage capacity of 360 mAh/g within 30 cycles. The reactivity of as-prepared Co3O4 in Li-ion cells could be attributed to nanosize particles of Co3O4 and its lithiation products.  相似文献   
94.
95.
Titanium carbide (TiC) particles have been coated with nickel (Ni) particles to increase compatibility between the TiC particles and the metal matrix based on Ni, leading to the improvement in the dispersion of TiC particles into a molten matrix, as functions of the potential hydrogen (pH) of TiC suspension, and the heat-treatment condition. The TiC particles were dispersed into the aqueous solution with various pH values, and then nickel nitrate (Ni(NO3)2) as a Ni precursor was added at the TiC suspension. As the pH is increased the content of Ni phase on the surface of TiC particle is increased, due to the increment of attractive force between the TiC particle and the Ni ion by the augmentation of negative value on the surface of TiC particle. The Ni-coated TiC particles heat treated at 500 °C under H2 atmosphere indicate the TiC and Ni phases only, whereas those heat treated at 1000 °C under Ar atmosphere show a titanium oxide (TiO2) with the TiC and Ni phases, which is resulted from the oxidation of TiC particle by oxygen contained in Ar gas. The dispersibility of TiC particles into a molten metal would be improved through the coating of Ni particles (or phase), inducing the improvement and reliability of mechanical properties.  相似文献   
96.
The fineness of reactants, degree of intermixing and interfacial contact area between fuel and oxidizer comprising of metastable intermolecular composite (MIC) particles are important factors to determine their overall kinetics of burning process. Here, we demonstrate a viable method for enhancing the explosive property of MICs by tailoring the nanostructures of oxidizer located in close proximity to fuel nanoparticles. The measured pressurization rate for a specific sample of solid Al nanoparticle (fuel)-porous CuO nanowire (oxidizer) MICs exploded in a closed vessel was found to be increased by a factor of ~ 10 compared with that for solid Al nanoparticle-solid CuO nanoparticle MICs. In addition, with the assistance of intensive sonication energy, the fabricated porous oxidizer nanowires were disintegrated into oxidizer nanoparticles, which considerably reduced the pressurization rate when they were ignited with fuel nanoparticles. This suggests that the morphology of oxidizer nanostructures from solid nanoparticles (i.e. 0-D) to porous nanowires (i.e. 1-D) play a key role in significantly changing the interfacial contact area with fuel nanoparticles so that nascent oxygen can be produced effectively for promoting the explosive property of the fuel nanoparticles.  相似文献   
97.
制备了一种水性丙烯酸改性环氧烤漆,用于五金家具的金属与玻璃底材上。考察了涂料的理化性能,并对其涂装方式作了探讨。  相似文献   
98.
Environment-friendly lime paints were prepared from 38 wt% slurries of hydrated lime (Ca(OH)2) and hydrated light burned dolomite (Ca(OH)2·Mg(OH)2). These materials and the resulting paints?? antibacterial and antimold properties were investigated. The hydrated lime used in this study contained 97 wt% Ca(OH)2, which implies a 71.85 wt% equivalence of CaO. This 71.85 wt% CaO content was responsible for the antibacterial and anti-mold characteristics. The antibacterial and anti-mold characteristics of the hydrated light burned dolomite were attributed to its 56 wt% CaO and 44 wt% MgO contents. The antibacterial-reducing activities of 38 wt% hydrated lime and hydrated light burned dolomite slurries were found to be 99%. Their anti-mold activities against mixed strains were outstanding. Lime paints produced from the slurries and various additives also showed 99% antibacterial activity and outstanding anti-mold activity. The paints?? low total volatile organic compounds (TVOCs) releases were graded as excellent. Their formaldehyde (HCHO) releases were classed as best through excellent, indicating their suitability as environment-friendly building materials.  相似文献   
99.
To effectively reduce CO2, CO2 mitigation technologies should be employed tactically. This paper focuses on carbon capture and storage (CCS) as the most promising CO2 reduction technology and investigates how to establish CCS strategy suitably. We confirm a major part of the optimal strategy for CCS infrastructure planning through a literature review according to mathematical optimization criteria associated with facility location models. In particular, the feasibility of large scale CCS infrastructure is evaluated through economic, environmental, and technical assessment. The current state-of-the-art optimization techniques for CCS infrastructure planning are also addressed while taking numerous factors into account. Finally, a list of issues for future research is highlighted.  相似文献   
100.
Zinc sulfide [ZnS] thin films were deposited on glass substrates using radio frequency magnetron sputtering. The substrate temperature was varied in the range of 100°C to 400°C. The structural and optical properties of ZnS thin films were characterized with X-ray diffraction [XRD], field emission scanning electron microscopy [FESEM], energy dispersive analysis of X-rays and UV-visible transmission spectra. The XRD analyses indicate that ZnS films have zinc blende structures with (111) preferential orientation, whereas the diffraction patterns sharpen with the increase in substrate temperatures. The FESEM data also reveal that the films have nano-size grains with a grain size of approximately 69 nm. The films grown at 350°C exhibit a relatively high transmittance of 80% in the visible region, with an energy band gap of 3.79 eV. These results show that ZnS films are suitable for use as the buffer layer of the Cu(In, Ga)Se2 solar cells.  相似文献   
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