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931.
近年来, 低维过渡金属硫族化合物Ta2NiSe7 因其独特的电荷密度波和特殊的拓扑能带结构而引起广泛关注. 本文利用拉曼光谱技术对准一维电荷密度波材料Ta2NiSe7 的声子模式进行了系统研究. 角度依赖的偏振拉曼光谱实验表明室温下可以观测到19 个拉曼峰, 且所有观察到的拉曼模式强度随样品旋转呈周期性变化, 这意味着Ta2NiSe7 具有较高的面内各向异性. 通过群论分析, 我们确定了拉曼峰的具体模式为Ag 和Bg 两种原子振动模式. 在温度依赖的偏振拉曼光谱测量中, 我们在低温下还观察到了新的声子峰, 推测与电荷密度波结构调制引起的晶格畸变有关. 本研究提供了对Ta2NiSe7 声子振动的全面理解, 这可能为进一步研究电荷密度波与声子振动之间的关联提供参考意义. 相似文献
932.
Dongjoon Lee Jong-Chan Park Keum Sim Jung Jiyeong Kim Ji Sung Jang Sunghoon Kwon Min Soo Byun Dahyun Yi Gihwan Byeon Gijung Jung Yu Kyeong Kim Dong Young Lee Sun-Ho Han Inhee Mook-Jung 《Experimental & molecular medicine》2022,54(1):61
The deposition of beta-amyloid (Aβ) in the brain precedes the onset of symptoms such as cognitive impairment in Alzheimer’s disease (AD); therefore, the early detection of Aβ accumulation is crucial. We previously reported the applicability of the QPLEXTM Alz plus assay kit for the prescreening of Aβ accumulation. Here, we tested the specific application of the kit in a large cohort of cognitively normal (CN) individuals of varying ages for the early detection of Aβ accumulation. We included a total of 221 CN participants with or without brain Aβ. The QPLEXTM biomarkers were characterized based on age groups (1st–3rd tertile) and across various brain regions with cerebral amyloid deposition. The 3rd tertile group (>65 years) was found to be the most suitable age group for the application of our assay kit. Receiver operating characteristic curve analysis showed that the area under the curve (AUC, discrimination power) was 0.878 with 69.7% sensitivity and 98.4% specificity in the 3rd tertile group. Additionally, specific correlations between biomarkers and cerebral amyloid deposition in four different brain regions revealed an overall correlation with general amyloid deposition, consistent with previous findings. Furthermore, the combinational panel with plasma Aβ1–42 levels maximized the discrimination efficiency and achieved an AUC of 0.921 with 95.7% sensitivity and 67.3% specificity. Thus, we suggest that the QPLEXTM Alz plus assay is useful for prescreening brain Aβ levels in CN individuals, especially those aged >65 years, to prevent disease progression via the early detection of disease initiation.Subject terms: Alzheimer''s disease, Neural ageing, ELISA 相似文献
933.
934.
935.
Lijia An Rongtang Ma Xichun Kou Xinyi Tang Bingzheng Jiang 《Macromolecular theory and simulations》1993,2(2):263-268
A statistical thermodynamics theory of polydisperse polymer mixtures with strong interaction between dissimilar components based on a lattice fluid model is formulated. Expressions for the free energy, equation of state, phase stability and spinodal for a polydisperse, binary polymer mixture with strong interaction are derived. 相似文献
936.
Zengqing Sun Qingyu Tang Xiaohui Fan Min Gan Xuling Chen Zhiyun Ji Xiaoxian Huang 《Molecules (Basel, Switzerland)》2022,27(1)
Alkali-activated materials (AAMs) are considered to be alternative cementitious materials for civil infrastructures. Nowadays, efforts have been made in developing AAMs with self-compacting ability. The obtained self-compacting AAMs (SCAAMs) accomplish superior passing and filling properties as well as excellent mechanical and environmental advantages. This work critically revisits recent progresses in SCAAMs including mixture proportions, fresh properties, mechanical strength, microstructure, acid and sulfate resistance, high temperature behaviors, impact resistance and interface shear strength. To facilitate direct comparison and interpretation of data from different publications, mixture proportions were normalized in terms of the content of key reactive components from precursors and activators, and correlation with mechanical behaviors was made. Moreover, special attention was paid to current research challenges and perspectives to promote further investigation and field application of SCAAMs as advanced construction material. 相似文献
937.
Wei Yang Anqianyi Tu Yuchen Ma Zhanming Li Jie Xu Min Lin Kailong Zhang Linzhi Jing Caili Fu Yang Jiao Lingyi Huang 《Molecules (Basel, Switzerland)》2022,27(1)
The application of chitosan (CS) and whey protein (WP) alone or in combination in 3D/4D printing has been well considered in previous studies. Although several excellent reviews on additive manufacturing discussed the properties and biomedical applications of CS and WP, there is a lack of a systemic review about CS and WP bio-inks for 3D/4D printing applications. Easily modified bio-ink with optimal printability is a key for additive manufacturing. CS, WP, and WP–CS complex hydrogel possess great potential in making bio-ink that can be broadly used for future 3D/4D printing, because CS is a functional polysaccharide with good biodegradability, biocompatibility, non-immunogenicity, and non-carcinogenicity, while CS–WP complex hydrogel has better printability and drug-delivery effectivity than WP hydrogel. The review summarizes the current advances of bio-ink preparation employing CS and/or WP to satisfy the requirements of 3D/4D printing and post-treatment of materials. The applications of CS/WP bio-ink mainly focus on 3D food printing with a few applications in cosmetics. The review also highlights the trends of CS/WP bio-inks as potential candidates in 4D printing. Some promising strategies for developing novel bio-inks based on CS and/or WP are introduced, aiming to provide new insights into the value-added development and commercial CS and WP utilization. 相似文献
938.
Laine研究小组直接用二氧化硅和乙二醇在无机碱的作用下,合成了五配位硅化合物:Laine研究的意义在于他开创了低温合成配位有机硅化合物的先河,这种方法有四个优点,(1)能耗小;(2)原料来源丰富,价格低廉,二氧化硅占地壳的1/4,乙二醇也很便宜;(3)污染小;(4)制得的五配位硅化合物反应活性非常高。但Laine在聚合物方面做的工作较少,过去只是把这个方法应用于高性能陶瓷玻璃的制备以及离子导电聚合物的研究中J,主要是解决不了五配位硅钾化合物的水解可逆性问题。 相似文献
939.
We study the Leibniz n-algebra Un(∑),whose multiplication is defined viathe bracket of a Leibniz algebra ∑ as[x1,...,xn]=[x1,[...,[xn-2,[xn-1,xn]]...]].Weshow that Un(∑) is simple if and only if ∑ is a simple Lie algebra.An analog of Levi'stheorem for Leibniz algebras in Un(Lb) is established and it is proven that the Leibnizn-kernel of Un(Σ) for any semisimple Leibniz algebra Σ is the n-algebra Un(Σ). 相似文献