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51.
For several years the treatment of metals like cp titanium and 316L stainless steel with concentrated chromosulfuric acid at high temperatures (230‐240 °C) has formed the basis for preparing ultra‐hydrophilic priming coats on these metals (Jennissen et al. Materialwiss. Werkstofftech. 30, 838‐845, 1999). Metals treated in this way have been called surface‐enhanced, displaying a characteristic ultrastructure, and can be easily modified to carry a biocoat of recombinant human bone morphogenetic protein 2 (rhBMP‐2). The major oxide on surface enhanced titanium is TiO2. Thus this TiO2‐layer could be responsible for the ultra‐hydrophilic properties of the priming coat. Irradiation of TiO2 layers by ultraviolet light (Wang et al., Nature 388, 431‐432, 1997) has been shown to endow these layers with ultra‐hydrophilic properties (i.e. contact angles of ~ 0°). However the ultra‐hydrophilic TiO2‐layers produced by irradiation are unstable and revert to the original high contact angles of ~ 70° within several days. The question of whether the ultra‐hydrophilic surfaces prepared by the chromosulfuric acid method show long‐term stability was therefore important to answer. In addition the question if rhBMP‐2 immobilized on such a surface will retain its biological activity was of great interest. In this paper it will be shown that ultrahydrophilic titanium mini‐plates retain their ultra‐hydrophilicity with contact angles of 0‐8° unchanged for at least 50 days and support the immobilization of rhBMP‐2 in a biologically active form.  相似文献   
52.
第三代办公自动化系统安全设计与实现研究   总被引:2,自引:0,他引:2  
从办公自动化入手,介绍了LotusNotes这个优秀软件,分析了第三代OA系统实现研究的基本内容、关键技术和难点,最后着重研究了它的安全设计实现。  相似文献   
53.
A major feeding deterrent forCostelytra zealandica larvae was isolated from the root of the resistant pasture legumeLotus pedunculatus and was identified as 3R-(—)-vestitol. This compound was also identified in feeding deterrent-activeL. pedunculatus leaf extracts. (—)-Vestitol and a secondLotus isoflavan, sativan, have been reported to have phytoalexin activity, and the implications of this for the study and understanding of insect resistance are briefly discussed.  相似文献   
54.
采用工业化生产工艺,通过清洗、筛分、离心分离等工艺,将莲藕中的淀粉和纤维、蛋白质及其它杂质分离开,制取精制的藕粉。日产精制藕粉在10吨以上,淀粉的提取率大于85%,适合工业化生产。  相似文献   
55.
Carbonic anhydrase (CA) plays a vital role in photosynthetic tissues of higher plants, whereas its non-photosynthetic role in the symbiotic root nodule was rarely characterized. In this study, 13 CA genes were identified in the model legume Lotus japonicus by comparison with Arabidopsis CA genes. Using qPCR and promoter-reporter fusion methods, three previously identified nodule-enhanced CA genes (LjαCA2, LjαCA6, and LjβCA1) have been further characterized, which exhibit different spatiotemporal expression patterns during nodule development. LjαCA2 was expressed in the central infection zone of the mature nodule, including both infected and uninfected cells. LjαCA6 was restricted to the vascular bundle of the root and nodule. As for LjβCA1, it was expressed in most cell types of nodule primordia but only in peripheral cortical cells and uninfected cells of the mature nodule. Using CRISPR/Cas9 technology, the knockout of LjβCA1 or both LjαCA2 and its homolog, LjαCA1, did not result in abnormal symbiotic phenotype compared with the wild-type plants, suggesting that LjβCA1 or LjαCA1/2 are not essential for the nitrogen fixation under normal symbiotic conditions. Nevertheless, the nodule-enhanced expression patterns and the diverse distributions in different types of cells imply their potential functions during root nodule symbiosis, such as CO2 fixation, N assimilation, and pH regulation, which await further investigations.  相似文献   
56.
This research was performed in order to compare the water and acetone extracts of raw and boiled for 10, 20, 40 and 60 min Korean lotus roots (KLR) and Polish white onion (PWO) in the contents of their bioactive compounds, antioxidant activity and thermostability.It was found that polyphenols (mg GAE/g), flavanols (μg GAE/g), flavonoids (mg CE/g), anthocyanins (mg CGE/kg) and tannins (mg CE/g) in water extract of raw lotus roots were 14.18 ± 0.7, 8.41 ± 0.5, 1.09 ± 0.06, 21.3 ± 1.2 and 7.29 ± 0.4, and of white onion - 11.11 ± 0.6, 6.78 ± 0.3, 0.71 ± 0.03, 17.00 ± 0.9 and 1.64 ± 0.08, respectively, and significantly higher in KLR (P < 0.05). The antioxidant activity of raw KLR water extract (139.4 ± 6.1, 53.1 ± 3.6 and 89.3 ± 4.6 μmol TE/g for DPPH, CUPRAC and ABTS, respectively) was significantly higher than in white onion (23.84 ± 1.8, 31.9 ± 2.1 and 38.14 ± 2.6 for DPPH, CUPRAC and ABTS, respectively, P < 0.05).The thermostability of the water KLR extract’s of polyphenols, flavanols, flavonoids, anthocyanins and tannins was high and even after 60 min of boiling remains as 40.0, 42.3, 50.5, 41.4 and 41.0%, respectively. After 60 min of boiling the most thermostable compounds were flavonoids - remaining at 50.5% in water extract of KLR. Also after 60 min of boiling the thermostability of the antioxidant activity of water extracts of KLR remained significantly high: 40.6, 42.3, 46.3 and 43.6%, according to DPPH, FRAP, ABTS and CUPRAC assays, respectively.Similar relationship was obtained with acetone extracts, but the value was lower than with the water ones. In conclusion, the contents of some bioactive compounds, the antioxidant activity and the thermostability in water and acetone extracts of KLR are significantly higher than the same indices in PWO. FTIR and fluorimetry can be used as additional markers for the characterization of bioactive compounds in vegetables.  相似文献   
57.
The antimicrobial equipment of materials is of great importance in medicine but also in daily life. A challenge is the antimicrobial modification of hydrophobic surfaces without increasing their low surface energy. This is particularly important for silicone‐based materials. Because most antimicrobial surface modifications render the materials more hydrophilic, methods are needed to achieve antimicrobial activity without changing the high water‐contact‐angle. This is achieved in the present work, where SiO2 nanoparticles are prepared and functionalized with 3‐(trimethoxysilyl)‐propyldimethyloctadecyl ammonium chloride (QAS) in a one‐pot synthesis. The modified nanoparticles are applied onto a silicone surface from suspension with no need of elaborate pretreatment. The resulting surface exhibits a Lotus‐Effect combined with contact‐active antimicrobial properties. The particle surfaces show self‐organizing micro‐ and nanostructures that afford a water‐contact angle of 144° and a hysteresis below 10°. The particles are self‐adhering on the silicone after solvent evaporation and resistant against immersion into and washing with water for at least 5 d. Thereby, the adhesion of the bacterial strain Staphylococcus aureus to these surfaces is reduced and the remaining bacterial cells are killed within 16 h. This is the first example of a Lotus‐Effect surface with intrinsic contact‐active antimicrobial properties.  相似文献   
58.
目的 探究不同采收期不同品种莲藕的营养成分和活性成分的变化规律。方法 选取5个采收期的4个品种莲藕,测定蛋白质、淀粉等指标。采用主成分分析和聚类分析进行综合评价,并建立莲藕品质评价模型。结果 在采收期内,莲藕淀粉含量呈现先上升后下降再上升的趋势,可溶性糖的变化趋势与其相反;总酚含量整体呈现先上升后下降的趋势;蛋白质、膳食纤维等指标呈现不同的变化规律。主成分分析法提取出PC1、PC2、PC3 3个主成分因子,特征值依次为2.274、1.933、1.023,累积方差贡献率达87.170%。不溶性膳食纤维、可溶性膳食纤维、可溶性总糖、淀粉、总酚和总黄酮6个指标可以用来综合评价莲藕营养品质。综合评价发现, 9月采收的八月粉,10月的鄂莲6号,2月的鄂莲10号和鄂莲11号,营养品质较好,优于其他采收期。3月采收的4个品种莲藕的综合营养品质较低。结论 在采收期内, 4个品种莲藕的营养物质动态规律存在一定差异。基于主成分分析和聚类分析的分析方法能够科学评价不同采收期莲藕的综合营养品质,为莲藕育种、加工等提供支撑。  相似文献   
59.
群件与Lotus Notes   总被引:2,自引:0,他引:2  
介绍了群件这一新概念的定义,分类及技术支持,并结合Llotus Notes这一具体产品,剖析了群件产品的基本构成要素。  相似文献   
60.
荷叶中抑菌成分的提取及其抑菌活性的研究   总被引:38,自引:4,他引:34  
纪丽莲 《食品科学》1999,20(8):64-66
以乙醇溶液对荷叶进行抽提试验,得到了荷叶提取物;用荷叶提取物对几种常见的食品微生物进行抑菌活性测定,结果表明,荷叶的抑菌作用显著,且对大多数供试菌的MIC(最低抑菌浓度)值小于或等于8%。[实验结果同时表明了荷叶提取物在中、弱碱性条件下抑菌活性最强,并能耐受高温短时及超高温瞬时的热处理。  相似文献   
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