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排序方式: 共有586条查询结果,搜索用时 15 毫秒
111.
TiAl过渡层对电弧离子镀沉积TiAlN膜层的影响 总被引:6,自引:0,他引:6
利用电弧离子镀,在不锈钢和SiCP增强2024铝基复合材料基底上沉积TiAlN薄膜.结果表明:TiAlN膜层直接沉积在不锈钢基底上,膜层呈[111]择优取向;然而,TiAlN膜层沉积在不锈钢基底的TiAl过渡层上,膜层呈[220]方向择优取向;并且随着过渡层从零开始增厚,TiAlN膜层的织构系数T(111)逐渐减小,而T(200)逐渐增大,但膜层一直以[220]方向择优取向,内应力的存在可能是膜层产生[220]方向择优取向的原因.在复合材料基底TiAl过渡层上沉积,随着负脉冲偏压的增加,TiAlN膜层的择优取向由[111]向[200]转变.在不锈钢基底上,没有TiAl过渡层时,膜层表面相对光滑,大颗粒较少;有了TiAl过渡层,表面大颗粒较多;TiAl过渡层不同沉积时间对膜层表面影响不大,颗粒尺寸相差无几.没有TiAl过渡层时,膜层结合强度很差,有了TiAl过渡层,结合强度明显增加,但结合强度的大小随过渡层沉积时间(厚度)变化. 相似文献
112.
Luiza-Andreea Tnase Oana-Viorela Nistor Gabriel-Dnu Mocanu Doina-Georgeta Andronoiu Adrian Cîrciumaru Elisabeta Botez 《Molecules (Basel, Switzerland)》2022,27(22)
Galactagogue herbs, also known as natural lactation adjuvants, are frequently used to stimulate breast milk production. Due to their antioxidant activity and phenolic content, anise (Pimpinella anisum L.) and fennel (Foeniculum vulgare L.) were chosen to increase the added value of zucchini (Cucurbita pepo L.) purees. At the same time, this work aimed to determine the influence of heat treatment on various characteristics of the final product. The phytochemical content, color parameters, and rheological and textural parameters of zucchini purees enriched with herbal aqueous extracts were determined after processing and after one week of storage (4 °C). In the case of antioxidant activity, samples registered a variation between 6.62 ± 1.71 and 38.32 ± 3.85 µM Trolox/g DW for the samples processed by steam convection. The total difference color parameter (ΔE) increased seven times after one week of storage compared to samples at T0. Fennel and anise aqueous extracts helped improve the rheological behavior of zucchini samples both by steam and hot air convection. This study may serve as a springboard for future investigations and clinical trials into the scientific validity and safety of ready-to-eat foods with special destinations. 相似文献
113.
Ana Fernandes Sara Simes Isabel M. P. L. V. O. Ferreira Maria Joo Alegria Nuno Mateus Anabela Raymundo Victor de Freitas 《Molecules (Basel, Switzerland)》2023,28(1)
This work explores the potential of Rocha do Oeste pear pomace to be used as a sustainable and healthy food ingredient. Moreover, the enrichment with yeast protein extract (YPE) may be useful to design innovative food products. The main goals of this study were to assess pear pomace concerning: (i) chemical composition and antioxidant capacity; (ii) rheology, texture, and microstructure characterization (alone or enriched with YPE), before and after heating. The results showed that pear pomace was a rich source of dietary fibers (74.5% DW), with phenolic compounds (3.9 mg chlorogenic acid equivalents/g dry weight), also presenting antiradical activity (3.90 μmol Trolox equivalents/g DW). Pear pomace showed a shear thinning behavior and a typical soft-gel behavior, which was not affected by YPE enrichment, thus suggesting that YPE did not affect pear pomace technological properties. Thermal treatment also did not alter pear pomace rheological properties. YPE addition induced a decrease in the apparent viscosity and a destabilizing effect, compared to the samples that were subjected to thermal processing. These results highlight the importance of pear pomace and the use of YPE for protein enrichment, opening new opportunities for their exploitation. 相似文献
114.
土壤质地分类的近红外光谱分析方法研究 总被引:13,自引:0,他引:13
依据所收集的25种土样,采用两种不同精度仪器、三种光谱方法以及3个不同谱区,在四种分类标准条件下进行土壤质地分类分析方法研究。结果表明:(1)土壤化学组成的信息主要体现在近红外光谱的谱峰特征,而质地等物理信息主要反映在光谱的斜率、截距参数上,且二者在不同谱区的相对强度不同;(2)近红外光谱方法对土壤质地的分辨能力较低,随着分类粗化而有所提高;(3)在4组分类标准中土壤质地最高预测准确度为72%,其中在砂粒<70%和粘粒<40%条件下,预测准确度达到85%;(4)样本顶部漫反射光谱方法与扩展谱区范围均可有效提高质地预测准确度,而高精度仪器并不具备明显优势。 相似文献
115.
用透射电子显微镜(TEM)和x射线衍射(XRD)方法对经300℃,2h退火的Ag和Cu自由膜和Si基体上的Ag和Cu附着膜的异常晶粒生长和织构变化进行了实验研究.XRD分析表明:Ag和Cu沉积膜均有(111)和(100)择优取向.但经退火处理后,Ag和Cu自由膜的(111)织构稍有加强.相反,Si基体上的Ag和Cu附着膜的(100)和(110)织构明显加强,同时用TEM在Cu附着膜中观察到了两个(110)和四个(211)取向的异常大晶粒.根据表面能和应变能的各向异性对实验结果进行了分析. 相似文献
116.
Neutrino-mass textures proposed at high scales are known to be unstable against radiative corrections especially for nearly
degenerate mass eigenvalues. We find a mechanism in a class of gauge models including 2HDM where the RG constraints can be
evaded. Consequently, a high-scale texture can match the low-energy data or be reproduced at low energies. 相似文献
117.
液晶等各向异性物体偏振光学图案的格栅计算方法和解析计算方法 总被引:2,自引:0,他引:2
本文推广获得了计算偏振光学图案的格栅方法,指出该方法可以处理具有任意指向矢排布的各向异性物体。进一步用色块显示法可获得层次丰富的理论图案。通过理论计算和安验观察,验证了运用偏光显微法可以鉴别液晶缺陷的强度与符号,这将有助于从微观水平上认识向列型液晶的纹影织构。等θ条件下,格栅方法可以过渡到解析方法,在单色光和多色光照射下的计算公式均已给出。 相似文献
118.
Kazuhiko Kandori Akemi Yasukawa Tatsuo Ishikawa 《Journal of colloid and interface science》1996,180(2):446
The structure and properties of hematite particles obtained by hydrolysis of ferric chloride solution doped with various kinds of amines were examined by TEM, XRD, TG-DTA, N2and H2O adsorption, and zeta potential measurements. The shape of precipitates was concentration dependent; they changed from large spheres (diameter: ca. 820 nm) to cubes (edge length: ca. 400 nm) via double-spheres (long axis length: ca. 600 nm) with increasing monoamine concentrations. This effect was enhanced by increasing their pKavalues. Much pronounced effects of di- and triamines on the particle formation were observed; cubic and double-spherical particles were obtained at a much lower concentration of di- and triamines and small spherical (diameter: ca. 100 nm) and diamond-like (long axis length: ca. 100 nm) particles were further produced at higher concentration. It was suggested that the acceleration of the rate of phase transformation from β-FeOOH to hematite induced by amines plays an important role for producing fairly uniform hematite particles with different shape and size. The hematite particles produced with amines contained small amounts of OH−ions in the lattice but were confirmed to be nearly single crystal. 相似文献
119.
水蒸气处理对HZSM-5分子筛催化剂的酸性及孔结构的影响 总被引:4,自引:2,他引:4
通过XRD,NH3-TPD,IR,比表面与孔结构测定等方法,研究了HZSM-5分子筛(硅铝比为38)在不同温度下进行水热处理时的酸性与孔结构。结果表明,随着水热处理温度的提高,HZSM-5分子筛的结晶度稍有增大;酸性明显减弱,弱酸位增多,强酸位相对减少;IR谱图上有一定的蓝移;比表面与微孔体积减小,介孔体积增大。 相似文献
120.
比较研究了几种改性煤焦油沥青的炭化性质,并从原料结构上给出了解释。结果表明:在同一热处理条件下形成的各种中间相沥青的光学显微结构区域的大小顺序为:S-LDOHF-MCTP>S-MCTP>MCTP-PS>MCTP共炭化沥青分子中含有较多的短烷基侧链和环烷结构,炭化时能形成可溶性较好的广域型中间相体;超临界抽提能调整沥青的族组成和分子量分布,使分子更易于均匀聚合和取向,超临界抽提沥青的炭化性能优于抽提 相似文献