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排序方式: 共有4133条查询结果,搜索用时 62 毫秒
941.
Linear copolymers from N-isopropylacrylamide(NIPA),acrylic acid(AA)and diacetone acrylamide(DAA)have been prepared. The effect of composition,ionic strength and pH on their lower critical solution temperature(LCST)has been investigated.  相似文献   
942.
943.
Chemistry of Natural Compounds - An endophytic strain F169 was isolated from the plant Huperzia serrata. It was identified as Colletotrichum sp. based on the sequence at the internal transcribed...  相似文献   
944.
Li  Jian  Yang  Yi Ni 《数学学报(英文版)》2021,37(12):1933-1946
Acta Mathematica Sinica, English Series - We study several stronger versions of sensitivity for minimal group actions, including n-sensitivity, thick n-sensitivity and blockily thick n-sensitivity,...  相似文献   
945.
Journal of Thermal Analysis and Calorimetry - In this investigation, a T-joint numerical welding simulation of thick steel plates is performed to estimate transient temperature distributions,...  相似文献   
946.
947.
In this paper, we consider the uniform estimates of strong solutions in the Mach number ? and t ∈ [0,) for the compressible nematic liquid crystal flows in a 3‐D bounded domain , provided the initial data are small enough and the density is close to the constant state. Here, we consider the case that the velocity field satisfies the Dirichlet boundary condition. Based on the uniform estimates, we obtain the global convergence of the compressible nematic liquid crystal system to the incompressible nematic liquid crystals system as the Mach number tends to zero.  相似文献   
948.
Liu  Shanshan  Liu  Xiujing  Wang  Qiang  Wang  Yingchao  Ji  Xingxiang  Yang  Guihua  Chen  Jiachuan  Ni  Yonghao 《Cellulose (London, England)》2022,29(3):1993-2003
Cellulose - Superhydrophobic and strong cellulosic paper was fabricated in a two-step process consisting of heavy refining and dip coating with PDMS (trimethylsiloxy-terminated poly...  相似文献   
949.
Fluorophores with emission in the second near-infrared window (NIR-II) have displayed salient advantages for biomedical applications. However, the common strategy of reducing the energy bandgap of fluorophores so as to achieve red-shifted wavelengths always leads to compromised fluorescent brightness. Herein, we propose a molecular design concept of “ring-fusion” to modify the acceptor of AIEgen that can extend the luminous wavelength from NIR-I to NIR-II. The fused-acceptor-containing fluorophore yielded, TTQP, has an enhanced absorption coefficient with a higher brightness in nanoparticle formation compared to its NIR-I emissive counterpart (TTQ-DP) with a non-fused acceptor. Theoretical calculation further confirms that the ring fusion can efficiently promote the rigidity and planarity of the electron-deficient core, leading to a lower reorganization energy and nonradiative decay. The TTQP NPs yielded thus allow sensitive NIR-II fluorescence imaging of vasculature and intestinal inflammation in mice models. Therefore, we anticipate that our work will provide a promising molecular-engineering strategy to enrich the library and broaden the application scope of NIR-II fluorophores.  相似文献   
950.
S-(Trifluoromethyl)benzothioate (TFBT) has been developed as an inexpensive, bench-stable, and user-friendly trifluoromethylthiolation reagent, which can be easily synthesized by using KF as the only fluorine source. By using TFBT, trifluoromethylthiolates with various counterions can be readily obtained. The synthetic application of TFBT was demonstrated by trifluoromethylthiolation-halogenation of arynes, bis(trifluoromethylthiolation)–halogenation of 1,2-benzdiynes, nucleophilic substitution of alkyl halides, deoxytrifluoromethylthiolation of alcohols, and cross-coupling with aryl and vinyl boronic acids.  相似文献   
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