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991.
A novel route was introduced to synthesize dense polyacrylamide (PAM) onto the glass slide surface. To investigate the surface chemistry of the PAM on the glass slides, X-ray photoelectron spectroscopy (XPS) was utilized to obtain detailed chemical state information on the PAM layer constituents. The XPS peak data were consistent with the presented model of the PAM on the glass slide surface. Scanning electron microscopy and atomic force microscope data indicated the presence of PAM on the glass slides, which consist of nodules. The results showed that PAM was successfully immobilized onto glass slides with a two-tier structure under aqueous condition and a monolayer structure under anhydrous condition. Compared with those under aqueous condition, the controllability of the molecular layer on glass slides and the reproducibility under anhydrous condition were much better, which makes anhydrous condition an advisable condition for the study of the reaction mechanisms of glass slides modified by PAM.  相似文献   
992.
Controlled release formulation of pesticides is highly desirable for attaining the most effective utilization of the pesticide as well as reducing environmental pollution. Nano-sized controlled release formulations can provide better penetration through cuticle and deliver the active ingredients efficiently to the targeted tissue. In this study, a novel strategy for the preparation of a nanoconjugate derived from kasugamycin with amino-modified silica was developed. The kasugamycin was connected with amino-modified silica matrix by an amide bond, which could avoid the initial burst release effectively and prolong the duration remarkably. The results showed the kasuga-silica can protect kasugamycin against photo-degradation effectively and the release rate of the active ingredient of nanoconjugate was related to the temperature, pH value, and the particle size (52.5–315.4 nm). With reduced particle size as well as increased temperature and acidity, the release of the active ingredient was faster. This amide linkage of kasuga-silica could be degraded by amidase effectively. This nanoconjugate displayed a better and a sustained bactericidal efficacy against E. coli than kasugamycin technical, which makes it a potential candidate as a controlled release conjugate for kasugamycin in the future.  相似文献   
993.
994.
The corrosion inhibition of ammonium heltamolybdate (AH) and calcium gluconate (CG) for AA6061 alloy in 3% NaCl solution was investigated by the electrochemical measurements. It indicates that AH inhibits the corrosion of AA6061 alloy and acts as an anodic inhibitor. Maximum inhibition efficiency reaches 74.3% at the concentration of 1 × 10?4 mol.l?1 AH. The results of the electrochemical studies reveal AH is physically adsorbed on the AA6061 alloy surface and the adsorption follows Langmuir isotherm. The combination of AH and CG enhances the inhibition efficiency to 95.9%. The enhanced inhibition is attributed to the promotion of AH adsorption by CG. The mixture of AH and CG is a mixed‐type inhibitor and renders the corrosion potential to more positive values. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
995.
A simple technique for patterning organic materials using a surfactant assisted lift-off method is proposed. Thin films of various organic materials are prepared, and areas in contact with a surfactant coated poly(dimethylsiloxane) (PDMS) stamp are selectively removed. The general applicability of this technique is shown for materials containing nitrate, amine, and carboxylic acid functional groups. This technique provides a new methodology for fabricating patterns with vertical dimensions ranging from 30 nm up to 3 μm on organic thin films with specific functional groups.  相似文献   
996.
997.
Small RNA has recently drawn more and more attention. In this paper, we concentrate on the influence of noises on gene network regulated by small RNA using chemical Langevin equation. It shows that the noise can cause oscillation when the oscillate does not occur in the corresponding deterministic system. The coherence of the noise induced oscillation reaches a maximum for an optimal intensity of noise, and the coherence resonance appears accordingly. The findings imply probably omnipresent importance of noise in the functioning process of living organism.  相似文献   
998.
999.
This paper summarizes the main achievements about the structure–activity relationships of anthocyanidin glycosylation. Anthocyanidin glycosylation is the essential step of anthocyanin biosynthesis and also the prerequisite of the further modifications of anthocyanins, which is jointly characterized by the glycosylation site, the type and number of the glycosyl as well as the glycosidic bond type. It generally enhances the stability, results in the hypsochromic effect and blueing, decreases the bioavailability and anticancer activity, and decreases, increases, or does not change the antioxidant activity of the anthocyanidins or anthocyanins, which is synergetically determined by the glycosylation site and the type and number of the glycosyl. Thereinto, in nature, the blue hues caused by the glycosylation may also be reinforced by the formation of the anthocyanic vacuolar inclusions. This review could provide a reference for the research of the structure-optimizing and function-exploiting of anthocyanins.  相似文献   
1000.
Small scale models representing key vehicle structural elements, including both floorboards and bottom-mounted, downward V-shape hulls in various configurations, have been manufactured and subjected to a range of buried blast loading conditions. By varying surface stand-off distance and depth of burial for several hull and structure configurations, the input-scaled response of aluminum full-scale vehicle floorboards has been quantified using high speed stereo-vision. Specifically, the maximum vertical acceleration on the floorboard and the corresponding Head Injury Criterion (HIC15) are quantified as metrics to assess the severity of the blast event. Results show standard V-shaped hulls provide essential blast mitigation, with reductions in floorboard measurements up to 47X in maximum acceleration and HIC15. Though variations in protective hull geometry provide modest reductions in the severity of a floorboard blast event, results also show that personnel on typical floorboard structures during blast loading events will incur unacceptable shock loading conditions, resulting in either serious or fatal injury. A more appropriate design scenario would be to consider situations that employ frame-mounted passenger seating to reduce the potential for injury. A second set of experiments will be presented in Part II that focuses on frame motions and accelerations when steel frames and steel structures are employed with various frame connections and coatings for frame blast mitigation.  相似文献   
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