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991.
A supramolecular polymer was constructed from a light‐driven overcrowded alkene switch modified with two alkylated gallic acid amide pendants ( MSP‐1 ). Upon UV irradiation, stable MSP‐1 isomerized into unstable MSP‐2 , which induced the effective collapse of well‐defined cross‐linked supramolecular polymers, and the reassembly can be realized by aging at low temperature. 相似文献
992.
In contrast to the conventional wisdom that mechanics is a relatively mature subject, the new manifestation of mechanics in an extended or crossed form is unfolding. Mechanics is now powering all subjects, from physical sciences, life sciences to social sciences. We name this new phase for the development of mechanics X-Mechanics. The present article outlines the contents of X-Mechanics from four aspects: cross media, cross scales, cross compliances, and cross cyber/physical spaces. X-Mechanics constitutes an endless frontier of science and technology. 相似文献
993.
Journal of Applied Spectroscopy - Mislabeling and adulteration are problems in the food industry. Considering the frequent occurrence of safety affairs in agricultural products, it is necessary to... 相似文献
994.
Linewidth narrowing and other quantum coherent effects based on three-photon coherent population trapping (CPT) in Ca+ ions are investigated. If the propagation directions of the three lasers obey the phase matching condition, the dark linewidth resulting from the CPT can be very narrow, and it can be controlled by adjusting the parameters of the lasers. 相似文献
995.
Applied Mathematics and Mechanics - The flow around a square cylinder with a synthetic jet positioned at the rear surface is numerically investigated with the unsteady Reynolds-averaged... 相似文献
996.
Zhibo Qu Xiaolan Chen Jinwei Yuan Yunliang Bai Tong Chen Lingbo Qu Fujun Wang Xu Li Yufen Zhao 《Tetrahedron》2012,68(15):3156-3159
A convenient one-pot three-component approach leading to synthesis of a series of novel heterocyclic α-aminophosphonates starting either from 2-hydroxyacetophenones or 2-hydroxybenzaldehyes was developed. 相似文献
997.
998.
Optical windows with external surfaces shaped to satisfy operational environment needs are known as special windows. A novel special window, a sphere-cone-polynomial (SCP) window, is proposed. The formulas of this window shape are given. An SCP MgF2 window with a fineness ratio of 1.33 is designed as an example. The field-of-regard (FOR) angle is ±75°. From the window system simulation results obtained with the calculated fluid dynamics (CFD) and optical design software, we find that compared to the conventional window forms, the SCP shape can not only introduce relatively less drag in the airflow, but also have the minimal effect on imaging. So the SCP window optical system can achieve a high image quality across a super wide FOR without adding extra aberration correctors. The tolerance analysis results show that the optical performance can be maintained with a reasonable fabricating tolerance to manufacturing errors. 相似文献
999.
Oligomeric and fibrillar amyloid-β (Aβ) are principally internalized via receptor-mediated endocytosis (RME) by microglia, the main scavenger of Aβ in the brain. Nevertheless, the inflammatory cascade will be evoked after vast Aβ aggregate binding to pattern recognition receptors on the cell membrane, which then significantly decreases the expression of these receptors and further deteriorate Aβ deposition. This vicious circle will weaken the ability of microglia for Aβ elimination. Herein, a combination of metabolic glycoengineering and self-triggered click chemistry is utilized to engineer microglial membranes with ThS as artificial Aβ receptors to promote microglia to phagocytose Aβ aggregates. Additionally, to circumvent the undesirable immune response during the process of the bioorthogonal chemistry reaction and Aβ-microglial interaction, Mn-porphyrin metal–organic frameworks (Mn-MOFs) with superoxide dismutase (SOD) and catalase (CAT) mimic activity are employed to carry N-azidoacetylmannosamine (AcManNAz) and eradicate over-expressed reactive oxygen species (ROSs). The artificial Aβ receptors independent of a signal pathway involved in immunomodulation as well as Mn-MOFs with antioxidant properties can synergistically promote the phagocytosis and clearance of Aβ with significantly enhanced activity and negligible adverse effects. The present study will not only provide valuable insight into the rational design of the microglial surface engineering strategy via bioorthogonal chemistry, but also hold great potential for other disease intervention associated with receptor starvation.A combination of metabolic glycoengineering and self-triggered click chemistry is utilized to engineer a microglial membrane with ThS as artificial Aβ receptors to promote microglia to phagocytose Aβ aggregates. 相似文献
1000.