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81.
Polymer Bulletin - Investigating the compatibility mechanism of hybrid composites based on two polymers and one mineral nanofiller is a challenge that needs to be better understood. This study...  相似文献   
82.
This paper uses narrative accounts of private gardens in Britain from the Mass-Observation Archive (MO) to explore ideas of landscape, privacy and attachment that emerge from daily practices and routines in these ordinary domestic spaces. We argue for the domestic garden as a vernacular or ordinary landscape that displays tensions between the private and the public nature of home within ambivalent emotional responses. Extended personal narratives offer privileged access to a site of intense engagement and carefully guarded privacy, yet with varying levels of attachment. The garden is a space well described in Britain in its public form but less well known as a private, everyday landscape. In this way a cultural landscape study becomes a contemporary critical geography of an ordinary space.  相似文献   
83.
Cold sintering process (CSP) is an extremely low‐temperature sintering process (room temperature to ~200°C) that uses aqueous‐based solutions as transient solvents to aid densification by a nonequilibrium dissolution‐precipitation process. In this work, CSP is introduced to fabricate microwave and packaging dielectric substrates, including ceramics (bulk monolithic substrates and multilayers) and ceramic‐polymer composites. Some dielectric materials, namely Li2MoO4, Na2Mo2O7, K2Mo2O7, and (LiBi)0.5MoO4 ceramics, and also (1?x)Li2MoO4?xPTFE and (1?x)(LiBi)0.5MoO4?xPTFE composites, are selected to demonstrate the feasibility of CSP in microwave and packaging substrate applications. Selected dielectric ceramics and composites with high densities (88%‐95%) and good microwave dielectric properties (permittivity, 5.6‐37.1; × f, 1700‐30 500 GHz) were obtained by CSP at 120°C. CSP can be also used to potentially develop a new co‐fired ceramic technology, namely CSCC. Li2MoO4?Ag multilayer co‐fired ceramic structures were successfully fabricated without obvious delamination, warping, or interdiffusion. Numerous materials with different dielectric properties can be densified by CSP, indicating that CSP provides a simple, effective, and energy‐saving strategy for the ceramic packaging and microwave device development.  相似文献   
84.
85.
Marama bean is a protein-rich, underutilised, drought-tolerant legume in sub-Saharan Africa. Its utilisation may be increased through value addition into protein-rich flours. Defatted flour from unheated and dry-heated (150 °C/20 min) whole marama beans (UMF and HMF) were analysed for physicochemical and protein-based functional properties. Heating significantly increased in vitro protein digestibility of marama bean flour. Of functional importance are the high levels of tyrosine present in marama bean flours. Heating significantly reduced protein solubility and emulsifying capacity of marama bean flours whilst water absorption capacity was improved. Foaming capacity was not affected by heating. UMF could be useful in food systems requiring high emulsifying capacity, but would not be suitable for applications requiring high water absorption and foaming capacity. Due to its high protein contents, marama bean flour could be used to increase the protein quality of cereal-based foods to help alleviate protein-energy nutrition in the region.  相似文献   
86.
The postsynaptic density (PSD) is a massive protein complex, critical for synaptic strength and plasticity in excitatory neurons. Here, the scaffolding protein PSD-95 plays a crucial role as it organizes key PSD components essential for synaptic signaling, development, and survival. Recently, variants in DLG4 encoding PSD-95 were found to cause a neurodevelopmental disorder with a variety of clinical features including intellectual disability, developmental delay, and epilepsy. Genetic variants in several of the interaction partners of PSD-95 are associated with similar phenotypes, suggesting that deficient PSD-95 may affect the interaction partners, explaining the overlapping symptoms. Here, we review the transmembrane interaction partners of PSD-95 and their association with neurodevelopmental disorders. We assess how the structural changes induced by DLG4 missense variants may disrupt or alter such protein–protein interactions, and we argue that the pathological effect of DLG4 variants is, at least partly, exerted indirectly through interaction partners of PSD-95. This review presents a direction for functional studies to elucidate the pathogenic mechanism of deficient PSD-95, providing clues for therapeutic strategies.  相似文献   
87.
南翼山构造三维地震资料解释是按下述步骤进行的:①首先根据已有钻井分层数据和各种测井曲线进行层位标定;②然后利用Apollo工作站的SEISTAR解释软件包具有垂直剖面和时间切片相关联的功能。进行层位拾取,生成时间构造图;③对工区内已有声测曲线进行各种校正建立三维速度数据体;④然后利用三维速度数据体与等t_0图得到解释层位的平均速度图;⑤利用Apollo的MAPSTAR绘图软件包的相应模块,把时间构造图和平均速度图的两个数据文件进行相应的运算,即可得到深度构造图。综合钻井和地震的各种信息分析认为,低频、低速、强能量是南翼山构造高产油气层的主要特征。据此,落实了渐新统顶高产油气层和中部上新统内一油层的分布范围。  相似文献   
88.
P—SV波和SH波的AVO分析   总被引:8,自引:1,他引:8  
地震反射振幅随炮检距变化的规律不仅纵波存在,横波同样也具有与物性参数有关的AVO特征。本文就P-SV波和SH波的AVO分析作了一些基础工作,其步骤与P波相仿,即从Zoeppritz方程出发,经过一系列可允许的简化,最后导出一些有地质地震属性的计算公式。研究结果发现:①利用P-SV波可以得到与SH波完全一样的地震属性;②从这些属性的数学模型可以发现,只要将现有P波的AVO分析软件稍作一些修改,便可用于横波AVO分析。本文一系列的模型演算结果说明,横波AVO是一项有潜力的技术。  相似文献   
89.
TiAl金属间化合物与42CrMo钢的真空扩散连接   总被引:5,自引:1,他引:4  
对TiAl金属间化合物与 4 2CrMo钢进行了真空扩散连接。采用扫描电镜对连接接头的显微组织和成分分布进行了初步地分析。研究发现 ,母材与中间层发生了扩散反应 ,采用加入中间层的真空扩散连接TiAl金属间化合物与 4 2CrMo钢具有良好的可焊性。  相似文献   
90.
穿甲弹从同口径到次口径、从钢质弹身材料到高密度钨、铀合金弹身材料的发展变化 ,使穿甲威力产生了两次飞跃。在长径比和弹身材料密度的进一步发展受到限制时 ,研究弹托材料 ,减少消极质量将是穿甲弹的又一次飞跃。本文介绍了几种新型弹托材料的发展和应用。  相似文献   
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