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301.
Graphene liquid cells (GLCs) for transmission electron microscopy (TEM) enable high‐resolution, real‐time imaging of dynamic processes in water. Large‐scale implementation, however, is prevented by major difficulties in reproducing GLC fabrication. Here, a high‐yield method is presented to fabricate GLCs under millimeter areas of continuous graphene, facilitating efficient GLC formation on a TEM grid. Additionally, GLCs are located on the grid using correlated light‐electron microscopy (CLEM), which reduces beam damage by limiting electron exposure time. CLEM allows the acquisition of reliable statistics and the investigation of the most common shapes of GLCs. In particular, a novel type of liquid cell is found, formed from only a single graphene sheet, greatly simplifying the fabrication process. The methods presented in this work—particularly the reproducibility and simplicity of fabrication—will enable future application of GLCs for high‐resolution dynamic imaging of biomolecular systems.  相似文献   
302.
Engineering with Computers - An iterative algorithm is a mathematical procedure that uses an initial value to generate a sequence of improving approximate solutions for a class of problems, in...  相似文献   
303.
Multimedia Tools and Applications - The adoption of the paradigm shift from push-based media broadcasting to pull-based media streaming has seen a significant growth in the recent decade. IPTV is...  相似文献   
304.
Up to now, the aluminide coatings used to protect industrial components at high temperature and corrosive environments have been modified by Pt, Cr, Si and Ni. In this investigation, aluminide coatings were modified by titanium and the microstructural feature and formation mechanism were evaluated. The coatings were formed on a Ni-based superalloy(IN738LC) by a two stage process including titanizing at first and aluminizing thereafter. Pack cementation titanizing performed at temperatures 950℃ and 1050℃ in several mixtures of Ti, Al2O3 and NH4Cl. At the second stage,aluminum diffused into surface of the specimens by an industrial aluminizing process known as Elcoatl01(4 hrs at 1050℃C). The modified coatings were characterized by means of standard optical microscopy, scanning electron microscopy,energy dispersive spectroscopy and X-Ray diffraction methods. The results show that Ti in the coatings is mainly present in the form of TiNi and Al67CrsTi25. Titanium modified coatings grew with a mechanism similar to simple aluminizing; this includes inward diffusion of Al from the pack to the substrate and then outward diffusion of Ni from the substrate to the coating. The advantages and characteristics of this two-stage modified coating is discussed and the process parameters are proposed to obtain a coating of optimum microstructure.  相似文献   
305.
A novel and clean one-pot synthesis of spiro[chromeno[2,3-c]pyrazole-4,3′-indoline]-2′,5(6H)-diones via cyclocondensation reaction of isatins, 1,3-cyclohexadiones, and pyrazolone in aqueous media using SBA-Pr-SO3H (sulfonic acid-functionalized mesoporous silica) as an efficient heterogeneous solid acid catalyst was reported. The antimicrobial activities of synthesized compounds have been tested.  相似文献   
306.
In the present study, the interpenetrated polymer networks (IPN) foams of polyurethane (PU) and poly(methyl methacrylate) (PMMA) with different ratio of PU/PMMA (i.e. 85/15, 75/25 and 65/35) were prepared using the polymerisation process. The acoustical, damping and thermal properties of synthesised IPN foams with regard to different compositions were studied. As indicators of effective damping capability, viscoelastic parameters including loss factor (tan δ), glass transition temperature (Tg) and effective damping interval (tan δ?>?0.3) were also determined. The results show that the Tg shifted to higher temperature ranges, and the damping temperature range (tan δ?>?0.3) increased when the IPN was formed. The sound absorption coefficient results show that because of the formation of IPN, the sound-absorbing capacity of prepared samples increased at a certain frequency, and the resonance frequency shifted to lower frequencies by increasing the PMMA content in IPN foams.  相似文献   
307.
Fabrication of Ge-based thermocouple on polyethylene-terephthalate (PET) plastic substrates is reported. The amorphous Ge film, deposited using electron beam evaporation, is post treated to form a polycrystalline film. The annealing process has been performed at temperatures ranging from 120/spl deg/C to 175/spl deg/C and study of physical characteristics of Ge films using XRD and SEM confirms its crystallinity. A value of 100 /spl mu/V//spl deg/C is extracted for the Ge-Al junctions. The thermocouple fabrication and its response to flow are reported. A novel approach is described to perform the micromachining of PET substrates for the formation of craters and membranes. Di-methyl-formamide (DMF) is used as the solvent of the PET substrate, masked with a Ge/Cu multilayer. An average chemical etch rate of 12 /spl mu/m/h is achieved in the presence of 6.5 mW/cm/sup 2/ of 360-nm UV at ambient temperature.  相似文献   
308.
309.
Posthaemorrhagic ventricular dilation following intraventricular haemorrhage is a serious problem with high morbidity in preterm babies. No consensus exists as to the treatment of intraventricular haemorrhage and as to the treatment or prophylaxis of posthaemorrhagic ventricular dilation. Serial lumbar tapping was already in use to treat existing or being in the offing ventricular dilation. In the present study we evaluated the incidence of posthaemorrhagic hydrocephalus when lumbar tapping was initiated early, i. e. immediately before ventricular dilation had started. Between January 1989 and December 1996 37 preterm infants suffering from intraventricular haemorrhage grade III or grade III plus periventricular haemorrhage were enrolled in this study. Lumbar tapping was started as soon as possible: median (25. percentile-75. percentile) two (0-4) days after onset of haemorrhage. A median of 11 (8-17) punctures was performed in each patient. The outcome was as follows: 6 patients (16.2%) showed complete remission, 24 (64.9%) developed ventriculomegaly and 7 (18.9%) developed posthaemorrhagic hydrocephalus with subsequent need of shunt implantation. With the low incidence of shunt implantations in our study we suggest to reconsider the effectiveness of SLP performed immediately after onset of haemorrhage.  相似文献   
310.
With data from 255 college women and men, this study examined the relative strength of relations of right-wing authoritarianism (RWA), social dominance orientation (SDO), and traditional gender role attitudes (TGRA) with anti-lesbian and gay (LG) attitudes. This study also tested the mediating role of anti-LG attitudes in the relations of RWA, SDO, and TGRA with LG-rejecting and -affirming behaviors. Results pointed to the importance of the relations of TGRA and RWA, but not SDO, with anti-LG attitudes and LG-rejecting behaviors. Furthermore, anti-LG attitudes mediated the links of RWA and TGRA with LG-rejecting behaviors. With regard to LG-affirming behaviors, TGRA was the only unique correlate, and anti-LG attitudes did not serve as a mediator. Implications for future research and practice are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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