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51.
采用原子吸收分光光度计测定了新疆岩蜥(Laudakia stoliczkana Blanford)和塔里木岩蜥(Laudakia tarimensis Zugmayer)全体、肌肉与皮肤中的K、Ca、Na、Mg、Fe、Zn、Mn、Sr、Cu、Mo、Cr、Ba、Co、V、Pb、Cd、Ni及Be18种元素的含量。结果表明,这两种岩蜥的常量元素和微量元素含量都比较丰富,其中K、Ca、Na、Mg、Fe、Zn、Sr、Mn、Cr、Br、Cu、Co、Mo含量比较高,而有毒元素Al、Pb、Ni和Cd的含量甚低。在这两种岩蜥全体、肌肉与皮肤三种样品中全体样品元素含量最高,但各元素含量的差异不明显。对两种岩蜥体内人体必需而具有抗癌作用的Fe、Zn、Sr、Mn等微量元素含量进行比较发现,新疆岩蜥分别为168.36、94.14、78.12、44.28μg/g,塔里木岩蜥分别为338.22、183.16、88.44、32.46μg/g。塔里木岩蜥中的Fe、Zn、Sr含量高于新疆岩蜥,而新疆岩蜥的Mn含量高于塔里木岩蜥。新疆岩蜥和塔里木岩蜥作为中药及维吾尔医药具有较高的药用价值及应用前景,并讨论了这些元素与其药用机理的关系,为这两种药用岩蜥的进一步研究及其开发利用提供科学依据。  相似文献   
52.
Decoding the relationship between crime and place has been the focus of researchers in both design and social fields for a few decades. Space syntax theory offers the possibility of examining the configuration characteristics of the environment and their potential influences on people’s activities and crime patterns; however, its implementation in landscape architecture has been limited. This study responds to such a gap by exploring the effectiveness of applying space syntax theory to predict safety levels in a park in Cairo, Egypt. depthmapX was used to analyze the spatial configuration of the park. Crime records from 2019 were collected through site observation and staff interviews, and analyzed using ArcGIS 10.3 software. Results indicated a strong correlation between space depth / integration / connectivity and crime pattern distribution. The park visibility graphs indicated the different impacts of vegetation (evergreen tree / deciduous trees) in summer and winter on visual connectivity and crime types. The research concluded that applying space syntax theory to landscape architecture is challenging; nevertheless, it represents a promising approach to predict committing crimes in urban parks, and the findings can be adopted to enhance park conceptual designs to achieve higher safety level.  相似文献   
53.
There were 18 electric vehicles, in average, per quick charger (QC), in Japan as of 2012, and this value may increase by a factor of several dozen by 2020. It is, therefore, necessary to model and analyze QC service, identify the causes of wait time, and provide countermeasures to avoid significant QC congestion and to encourage the spread of QC stations. This research analyzed usage data of a QC installed at an existing service area on expressway, and showed the characteristics of QC demand as distribution functions. QC service was modeled as a queuing problem, and simulations were carried out using derived distribution functions. The results showed that the QC station needs additional charger in the case of daily charging times over 10 times.  相似文献   
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Mg-based alloys received significant attention for temporary implant applications while, their applications have been limited by high degradation rate. Therefore, silver–zeolite doped hydroxyapatite (Ag-Zeo-HAp) coating was synthesized on TiO2-coated Mg alloy by physical vapour deposition (PVD) assisted electrodeposition technique to decrease the degradation rate of Mg alloy. X-ray diffraction (XRD) analysis and field emission scanning electron microscopy (FE-SEM) images showed the formation of a uniform and compact layer of Ag-Zeo-HAp with a thickness of 15 μm on the TiO2 film with a thickness of 1 μm. The potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) tests indicated that corrosion resistance of Mg-Ca alloy was considerably increased by the Ag-Zeo-HAp coating. The bioactivity test in the simulated body fluid (SBF) solution showed that a dense and homogeneous bonelike apatite layer was formed on the Ag-Zeo-HAp surface after 14 d. Investigation of antibacterial activity via disk diffusion and spread plate methods showed that the Ag-Zeo-HAp coating had a significantly larger inhibition zone (3.86 mm) towards Escherichia coli (E. coli) compared with the TiO2-coated Mg alloy (2.61 mm). The Ag-Zeo-HAp coating showed high antibacterial performance, good bioactivity, and high corrosion resistance which make it a perfect coating material for biomedical applications.  相似文献   
56.
Mg-based alloys received significant attention for temporary implant applications while, their applications have been limited by high degradation rate. Therefore, silver-zeolite doped hydroxyapatite(Ag-Zeo-HAp) coating was synthesized on Ti O_2-coated Mg alloy by physical vapour deposition(PVD) assisted electrodeposition technique to decrease the degradation rate of Mg alloy. X-ray diffraction(XRD) analysis and field emission scanning electron microscopy(FE-SEM) images showed the formation of a uniform and compact layer of Ag-Zeo-HAp with a thickness of 15 μm on the Ti O_2 film with a thickness of 1 μm. The potentiodynamic polarization(PDP) and electrochemical impedance spectroscopy(EIS) tests indicated that corrosion resistance of Mg-Ca alloy was considerably increased by the Ag-Zeo-HAp coating. The bioactivity test in the simulated body fluid(SBF) solution showed that a dense and homogeneous bonelike apatite layer was formed on the Ag-Zeo-HAp surface after 14 d. Investigation of antibacterial activity via disk diffusion and spread plate methods showed that the Ag-Zeo-HAp coating had a significantly larger inhibition zone(3.86 mm) towards Escherichia coli(E. coli) compared with the Ti O_2-coated Mg alloy(2.61 mm). The Ag-Zeo-HAp coating showed high antibacterial performance, good bioactivity, and high corrosion resistance which make it a perfect coating material for biomedical applications.镁基合金作为临时植入材料的应用受到了越来越多的关注,然而,由于其降解速率高,因此应用受到了限制。为了降低镁合金的降解速率,本文作者采用物理气相沉积(PVD)辅助电沉积技术在镀氧化钛(Ti O_2)的镁合金上涂覆掺银-沸石羟基磷灰石(Ag-Zeo-HAp)涂层。X射线衍射(XRD)分析和场发射扫描电镜(FESEM)图片显示,在厚度约为1μm的二氧化钛薄膜上形成了均匀且致密的Ag-Zeo-HAp涂层,厚度约为15μm。动电位极化(PDP)和电化学阻抗谱(EIS)测试表明,通过Ag-Zeo-HAp涂层,Mg-Ca合金的耐腐蚀性大大提高。模拟体液(SBF)浸泡测试生物活性试验结果表明,在14 d后的Ag-Zeo-HAp表面上形成了一层致密且均匀的类骨磷灰石层。采用琼脂扩散法和平板涂布法对抗菌活性进行研究。结果表明,与Ti O_2涂层的镁合金(2.61 mm)相比,Ag-Zeo-HAp涂层对大肠杆菌(E.coli)的抑制区(3.86 mm)明显增大。Ag-Zeo-HAp涂层具有良好的抗菌性能、良好的生物活性和耐腐蚀性,是生物医学应用的理想涂层材料。  相似文献   
57.
Porous silicon (PS) was fabricated by laser-induced etching (LIE) process. The objective of this study is to investigate the selected LIE parameters to control size and shape of nanostructures,which are considered important factors in semiconductor device applications. Photoluminescence output intensity becomes stronger due to the increase in the number of emitted photons on the porous surface. There is a dramatic increase in photoluminescence intensity due to the increase of porosity as a function of laser...  相似文献   
58.
The objective of this study was to establish suitable combinations of selected probiotics and nutraceuticals. Interactions among 24 probiotic strains were investigated, and the effect of a blend of isoflavones and phytosterols on viability of single and mixed probiotic strains under incubation and refrigeration storage in milk was assessed. Upon incubation, counts of single strains increased by 7–15 times, while mixed strains showed slight insignificant decrease. Both single and mixed probiotic strains retained high counts (>log 8) throughout refrigeration storage. Eight probiotic strains showed nil or very weak interactions. Results revealed the possibility of developing novel multibenefits synbiotic products using combinations of these probiotic strains and nutraceuticals.  相似文献   
59.
Reduced-fat stirred yoghurts were prepared by using ropy and nonropy exopolysaccharide (EPS)-producing strains or nonexopolysaccharide-producing strains. Yoghurts were evaluated for pH, titrable acidity, acetaldehyde, whey separation, viscosity, EPS concentration, sensory and microbiological analyses. Determinations of these parameters were made at 1, 7, 14 and 21 days of storage. Reduced-fat yoghurts made with EPS+ strains exhibited lower syneresis and acetaldehyde contents, but higher viscosity than those made with the EPS strain. Physico-chemical results correlated with the sensory results in that panellists scored the EPS+ yoghurts as having an overall better mouthfeel, but a worse flavour than EPS yoghurt.  相似文献   
60.
A range of French acid-type fresh cheeses of various commercial brands was tested by a trained sensory panel which detected significant differences in thickness, smoothness and slipperiness. The cheeses exhibited thixotropic behaviour. The perceived thickness of the samples was highly correlated with the shear stress values obtained for a limited range of shear rates (30–80 S−1). The area of the hysteresis loop formed during the first shearing cycle of the samples over a wide range of shear rates (4.5–450 S−1) was negatively correlated to slipperiness. The correlation matrix showed that the sensory attributes were independent of the chemical composition of the products. Principal components analysis indicated the way the three sensory attributes were related to each other and to the rheological parameters.  相似文献   
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