A Viologen-bearing Coordination Polymer with Multi-stimuli Responsive Behaviors

A viologen-bearing Zn（Ⅱ） coordination polymer, [Zn（Bpybc）SO₄]·H₂O, has been successfully synthesized and structurally characterized. The title compound exhibits sunlight and UV-induced photochromism, thermoschromism, and amine-selective chemochromism.     

多孔氮化硼掺杂聚吡咯-2,3,3-三甲基吲哚固相微萃取涂层的制备及多环芳烃的检测

多环芳烃(PAHs)是持久性有机污染物中的一种，大部分具有较强的致癌、致畸和致突变性，对生态环境和人类健康易造成严重威胁。由于环境样品基质复杂且其中PAHs含量低，因此在仪器分析之前需要对环境样品进行必要的前处理。萃取材料的特性是决定大部分前处理技术萃取效率的关键。基于此，本文以低成本且富含较多官能团的吡咯(py)、2,3,3-三甲基吲哚(2,3,3-TMe@In)为单体，多孔氮化硼为掺杂物，采用电化学循环伏安法制备出多孔氮化硼掺杂聚吡咯-2,3,3-三甲基吲哚(Ppy/P2,3,3-TMe@In/BN)复合涂层，通过扫描电子显微镜、热稳定性分析、傅里叶红外光谱等手段对Ppy/P2,3,3-TMe@In/BN进行表征，结果表明：该涂层呈现出多孔、多褶皱的枝状结构，该结构有利于增加涂层的比表面积，从而实现对PAHs的大量富集；在320℃解吸温度下，涂层材料的色谱基线基本稳定，表明该涂层具有良好的热稳定性。将其修饰在不锈钢丝表面制成固相微萃取涂层，结合气相色谱-氢火焰离子化检测器，对影响萃取和分离萘(NAP)、苊(ANY)、芴(FLU)3种PAHs的条件进行优化，建立了用于以上3种PAHs...     

Forthrightly monitoring ferroptosis induced by endoplasmic reticulum stresses through fluorescence lifetime imaging of microviscosity increases with a specific rotor

To test the hypothesis that the microviscosity changes of Endoplasmic Reticulum(ER) can be a useful indicator of ferroptosis promoted by ER Stresses(ERS), a new ER targeting viscosity rotor, L-Vis-1 was developed and applied in the quantitation of viscosity by FLIM imaging in live cells. The FLIM imaging exhibited an excellent resolution almost as good as the corresponding confocal imaging, more significantly, during ferroptosis processes promoted by different types of ERS, the viscosity increas...     

Numerical study of dynamic zigzag patterns in migrating epithelial tissue

Collective cell migration plays a crucial role in embryonic development, metastasis, and wound healing. Nevertheless, to the best of our knowledge, how the coordination between the cell motility and deformations affects the collective motion of epithelial cells is not fully understood. In this work, we propose a modified self-propelled Voronoi model for epithelial cell migration incorporating the coupling between the self-propulsion of cells and the polarization of the cell elongation. At a high coupling strength,we observe the emergence of backward traveling band structures formed by highly aligned cells, which can be regulated by cell elongations or shape anisotropy. Increasing the cell shape anisotropy, we find that large bands split into multiple small microbands. The latter essentially forms a dynamic zigzag pattern, in which the angle between the polarization direction of the bands and the migration direction switches alternatively between π/4 and-π/4 because the cells are forced to move preferentially in the anterior direction. We also analyzed the disclinations in the cell monolayer, force distribution near the domain boundaries and the shape alignment of the epithelial monolayer during the formation of this dynamic pattern. The present findings may further our understanding of stripe pattern formations in living systems and inspire potential designs for cell sorting.     

Cleavage/cross-coupling strategy for converting β-O-4 linkage lignin model compounds into high valued benzyl amines via dual C–O bond cleavage

Lignin is the most recalcitrant of the three components of lignocellulosic biomass. The strength and stability of the linkages have long been a great challenge for the degradation and valorization of lignin biomass to obtain bio-fuels and commercial chemicals. Up to now, the selective cleavage of C–O linkages of lignin to afford chemicals contains only C, H and O atoms. Our group has developed a cleavage/crosscoupling strategy for converting 4-O-5 linkage lignin model compounds into high value-a...     

基于MOF (Cu)@biochar气凝胶的制备及其在缓释氮肥上的应用

以羧甲基纤维素(CMC)、明胶和MOF(Cu)@biochar为原料,采用简单有效的冷冻干燥方法制备了(CMC/Gelatin/MOF(Cu)@biochar)杂化气凝胶,并用傅里叶变换红外光谱(FT-IR)、热重分析(TG)、X射线粉末衍射(XRD)、扫描电镜(SEM)和X射线光电子能谱(XPS)技术对其进行了表征;研究了MOF(Cu)@biochar含量、pH和不同的盐水溶液对杂化气凝胶溶胀行为的影响;以该气凝胶负载氯化铵,制备了一种新型缓释肥料(SRF),并研究了含2%(wt)SRF的沙性土壤的保水能力;SRF在土壤中第30天的累积释放率为79.4%;肥料在土壤中释放符合非Fickian扩散和阳离子交换的协同作用机理。     

Special John-Nirenberg-Campanato spaces via congruent cubes

Let p ∈ [1, ∞), q ∈ [1, ∞), α∈ R, and s be a non-negative integer. Inspired by the space JNp introduced by John and Nirenberg(1961) and the space B introduced by Bourgain et al.(2015), we introduce a special John-Nirenberg-Campanato space JN^con_(p,q,s) over Rⁿ or a given cube of R;with finite side length via congruent subcubes, which are of some amalgam features. The limit space of such spaces as p →∞ is just the Campanato space which coincides with the space BMO(the space of functions with bounded mean oscillations)when α = 0. Moreover, a vanishing subspace of this new space is introduced, and its equivalent characterization is established as well, which is a counterpart of the known characterization for the classical space VMO(the space of functions with vanishing mean oscillations) over Rⁿ or a given cube of Rⁿ with finite side length.Furthermore, some VMO-H¹-BMO-type results for this new space are also obtained, which are based on the aforementioned vanishing subspaces and the Hardy-type space defined via congruent cubes in this article. The geometrical properties of both the Euclidean space via its dyadic system and congruent cubes play a key role in the proofs of all these results.