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81.
82.
Planar Heterojunction Perovskite Solar Cells Incorporating Metal–Organic Framework Nanocrystals 下载免费PDF全文
83.
Ming-Jun Li Pei-Ching Kung Yuan-Wei Chang Nien-Ti Tsou 《International journal of molecular sciences》2020,21(23)
(1) Background: Our aim is to reveal the influence of the geometry designs on biophysical stimuli and healing patterns. The design guidelines for dental implants can then be provided. (2) Methods: A two-dimensional axisymmetric finite element model was developed based on mechano-regulatory algorithm. The history of tissue differentiation around eight selected implants can be predicted. The performance of the implants was evaluated by bone area (BA), bone-implant contact (BIC); (3) Results: The predicted healing patterns have very good agreement with the experimental observation. Many features observed in literature, such as soft tissues covering on the bone-implant interface; crestal bone loss; the location of bone resorption bumps, were reproduced by the model and explained by analyzing the solid and fluid biophysical stimuli and (4) Conclusions: The results suggested the suitable depth, the steeper slope of the upper flanks, and flat roots of healing chambers can improve the bone ingrowth and osseointegration. The mechanism related to solid and fluid biophysical stimuli were revealed. In addition, the model developed here is efficient, accurate and ready to extend to any geometry of dental implants. It has potential to be used as a clinical application for instant prediction/evaluation of the performance of dental implants. 相似文献
84.
John J. Petrovic Maria I. Pena Ivar E. Reimanis Michael S. Sandlin Samuel D. Conzone H. Harriet Kung Darryl P. Butt 《Journal of the American Ceramic Society》1997,80(12):3070-3076
The mechanical behavior of MoSi2 reinforced–Si3 N4 matrix composites was investigated as a function of MoSi2 phase content, MoSi2 phase size, and amount of MgO densification aid for the Si3 N4 phase. Coarse-phase MoSi2 -Si3 N4 composites exhibited higher room-temperature fracture toughness than fine-phase composites, reaching values >8 MP·am1/2 . Composite fracture toughness levels increased at elevated temperature. Fine-phase composites were stronger and more creep resistant than coarse phase composites. Room-temperature strengths >1000 MPa and impression creep rates of ∼10−8 s−1 at 1200°C were observed. Increased MgO levels generally were deleterious to MoSi2 -Si3 N4 mechanical properties. Internal stresses due to MoSi2 and Si3 N4 thermal expansion coefficient mismatch appeared to contribute to fracture toughening in MoSi2 -Si3 N4 composites. 相似文献
85.
Chien‐Hua Hsu Min‐Hsiang Hsu Kung‐Chin Chang Mei‐Chun Lai Pei‐Ju Liu Tsao‐Li Chuang Jui‐Ming Yeh Wei‐Ren Liu 《Polymer International》2014,63(10):1765-1770
In this study, the effects of different oxygen‐containing group contents in thermally reduced graphene oxides (TRGs) for enhancing the physical properties of epoxy nancomposites was examined. The epoxy/TRG nanocomposites (ETNs) were prepared by a room temperature curing method in the presence of TRGs containing different oxygen‐containing groups and were then characterized by Fourier transform infrared spectroscopy. TRG contents with higher oxygen‐containing group contents (ca 33%) were found to show better dispersion capability in the epoxy matrix than TRGs with lower oxygen‐containing group contents (ca 11%) based on morphological observations by transmission electron microscopy. The better dispersion capability of TRGs with higher oxygen‐containing group contents in ETN membranes was found to lead to significantly enhanced mechanical strength, thermal stability and thermal conductivity based on measurements of dynamic mechanical analysis, tensile tests, thermogravimetric analysis and by the transient plane source technique. © 2014 The Authors. Polymer International published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry 相似文献
86.
Effect of temperature on removal of heavy metals from contaminated river sediments via bioleaching 总被引:11,自引:0,他引:11
The aim of this study was to determine the effect of temperature on the solubilization of heavy metals from contaminated river sediment by sulfur oxidizing bacteria taken from Ell-Ren River sediment. Of three temperatures tested (25 degrees C, 37 degrees C and 55 degrees C), pH decrease was greatest at 37 degrees C, indicating that, after acclimation, bacterial oxidizing activity is greatest at this temperature. At 55 degrees C, pH change was similar to that which occurred with no inoculum added. The increase in sulfates and high pH at 55 degrees C indicate that the indirect mechanism was not initiated at this temperature. Solubilization efficiency of total extractable Ni, Zn, Cu and Cr was high (>90%) at 37 degrees C, whilst that of Pb was only 60.4%. Except for Pb, the optimal temperature for solubilization of total extractable heavy metal was 37 degrees C. The order of average solubilization efficiency of total extractable heavy metals was Ni, Zn, Cu>Cr>Co, Pb. The solubilization efficiency of Pb and Co was markedly less than that of other heavy metals. Transfer of heavy metals between binding fractions was most apparent at 55 degrees C before and after bioleaching. 相似文献
87.
Rates of degradation of DL-methionine and a number of methionine derivatives by rumen microorganisms were studied in vitro. Methionine hydroxy analog, the ammonium salt, and the amide derivative of methionine hydroxy analog were degraded more slowly than was methionine. Methyl and ethyl esters of methionine hydroxy analog were rapidly converted to methionine hydroxy analog, which was then degraded. Whole rumen contents were separated into protozoal and bacterial fractions, and rates of disappearance of [14C]carboxyl-labeled methionine and methionine hydroxy analog were determined. Disappearance of the label tended to be slower in the bacterial fraction; however, incorporation into cellular material tended to be higher for the bacterial than for the protozoal fraction. Disappearance of labeled methionine hydroxy analog was slower than labeled methionine in all fractions. Addition of unlabeled methionine inhibited disappearance of labeled methionine hydroxy analog, but unlabeled methionine hydroxy analog did not affect disappearance of labeled methionine. The effect of either Na2SO4, methionine, or methionine hydroxy analog on neutral detergent fiber digestion was related to amount of sulfur in the medium and not source of sulfur. 相似文献
88.
The effect of inoculating whole-plant corn at the time of harvest with Lactobacillus buchneri 40788 (4 × 105 cfu/g of fresh forage) combined with Pediococcus pentosaceus R1094 (1 × 105 cfu/g) on the fermentation and aerobic stability of corn silage (37% dry matter) through 361 d of ensiling was investigated. Dry matter recovery was similar between treatments throughout the study except at one early time point (14 d), when treated silage had a lower recovery than untreated silage. The concentration of lactic acid was unaffected by inoculation but inoculated silages had greater concentrations of 1,2-propanediol and acetic acid from 56 to 361 d of storage. In general, inoculation decreased the concentration of water-soluble carbohydrates but increased the concentration of ethanol. The numbers of yeasts was lower in inoculated silage at 42, 56, 70, and 282 d of ensiling. However, inoculation did not consistently improve the aerobic stability of silage, suggesting that microbes other than yeasts may have been responsible for aerobic instability in this study. Even after prolonged storage (361 d), silage treated with L. buchneri 40788 and P. pentosaceus R1094 had normal silage fermentation characteristics. 相似文献
89.
Because of the relative ease to modify, functionalize, and synthesize polysiloxanes, these compounds offer interesting possibilities to greatly influence the properties of a catalytic system. These potentials are illustrated with three catalytic systems. In the first system, siloxane nanocages are shown to exhibit confinement effects by strongly modifying the protonation affinity of internal amine groups and by changing the activity and product selectivity in a reaction catalyzed by these groups. In the second example, the length of the siloxane backbone of a bis(pyridyl)siloxane ligand is shown to be critical both in stabilizing a Pd acetate complex catalyst in selective oxidation of benzyl alcohol, and in determining the dependence of the reaction rate on the pyridyl concentration in the reaction mixture. In the third example, polysiloxanes are shown to be useful in the preparation of a supported Pd catalyst in which the metal loading and particle size can be independently controlled. 相似文献
90.
The impending doom of CMOS scaling has semiconductor mavericks scrambling for alternative solutions to continue increasing the device density per chip. One serious candidate is 3D integration in which the planar manufacturing technology extends skyward into the third dimension, much like skyscrapers. Similarities between chip architecture and building architecture are plentiful, and the author draws some parallels between the two. 相似文献