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991.
Coulter–Matthews (CM) bent functions are from to defined by , where and (α,2n)=1. It is not known if these bent functions are weakly regular in general. In this paper, we show that when n is even and α=n+1 (or n−1), the CM bent function is weakly regular. Moreover, we explicitly determine the dual of the CM bent function in this case. The dual is a bent function not reported previously. 相似文献
992.
Lijiao Ma Prof. Shaoqing Zhang Junzhen Ren Guanlin Wang Jiayao Li Zhihao Chen Huifeng Yao Prof. Jianhui Hou 《Angewandte Chemie (International ed. in English)》2023,62(5):e202214088
To modulate the miscibility between donor and acceptor materials both possessing fully non-fused ring structures, a series of electron acceptors (A4T-16, A4T-31 and A4T-32) with different polar functional substituents were synthesized and investigated. The three acceptors show good planarity, high conformational stability, complementary absorption and energy levels with the non-fused polymer donor (PTVT-BT). Among them, A4T-32 possesses the strongest polar functional group and shows the highest surface energy, which facilitates morphological modulation in the bulk heterojunction (BHJ) blend. Benefiting from the proper morphology control method, an impressive power conversion efficiency (PCE) of approaching 16.0 % and a superior fill factor over 0.795 are achieved in the PTVT-BT : A4T-32-based organic photovoltaic cells with superior photoactive materials price advantage, which represent the highest value for the cells based on the non-fused blend films. Notably, this cell maintains ≈84 % of its initial PCE after nearly 2000 h under the continuous simulated 1-sun-illumination. In addition, the flexible PTVT-BT : A4T-32-based cells were fabricated and delivered a decent PCE of 14.6 %. This work provides an effective molecular design strategy for the non-fused non-fullerene acceptors (NFAs) from the aspect of bulk morphology control in fully non-fused BHJ layers, which is crucial for their practical applications. 相似文献
993.
Dr. Ying-Jie Sun Wen-Da Chen Dr. Ji Liu Jun-Jin Li Yu Zhang Wei-Qi Cai Prof. Li Liu Xin-Jing Tang Jian Hou Prof. Ming Wang Prof. Liang Cheng 《Angewandte Chemie (International ed. in English)》2023,62(5):e202212413
The CRISPR/Cas system is one of the most powerful tools for gene editing. However, approaches for precise control of genome editing and regulatory events are still desirable. Here, we report the spatiotemporal and efficient control of CRISPR/Cas9- and Cas12a-mediated editing with conformationally restricted guide RNAs (gRNAs). This approach relied on only two or three pre-installed photo-labile substituents followed by an intramolecular cyclization, representing a robust synthetic method in comparison to the heavily modified linear gRNAs that often require extensive screening and time-consuming optimization. This tactic could direct the precise cleavage of the genes encoding green fluorescent protein (GFP) and the vascular endothelial growth factor A (VEGFA) protein within a predefined cutting region without notable editing leakage in live cells. We also achieved light-mediated myostatin (MSTN) gene editing in embryos, wherein a new bow-knot-type gRNA was constructed with excellent OFF/ON switch efficiency. Overall, our work provides a significant new strategy in CRISPR/Cas editing with modified circular gRNAs to precisely manipulate where and when genes are edited. 相似文献
994.
Dr. Jia-Hao Xie Yi-Ming Hou Zuolijun Feng Prof. Dr. Shu-Li You 《Angewandte Chemie (International ed. in English)》2023,62(10):e202216396
Herein, we report a synthesis of cyclohexanones bearing multi-continuous stereocenters by combining copper-catalyzed asymmetric conjugate addition of dialkylzinc reagents to cyclic enones with iridium-catalyzed asymmetric allylic substitution reaction. Good to excellent yields, diastereoselectivity and enantioselectivity can be obtained. Unlike the stereodivergent construction of adjacent stereocenters (1,2-position) reported in the literature, the current reaction can achieve the stereodivergent construction of nonadjacent stereocenters (1,3-position) by a proper combination of two chiral catalysts with different enantiomers. 相似文献
995.
Ni-Yuan Zhang Da-Yong Hou Xing-Jie Hu Jian-Xiao Liang Man-Di Wang Zhang-Zhi Song Li Yi Zhi-Jia Wang Prof. Hong-Wei An Prof. Wanhai Xu Prof. Hao Wang 《Angewandte Chemie (International ed. in English)》2023,62(37):e202308049
Proteolysis targeting chimera (PROTAC) is an emerging pharmacological modality with innovated post-translational protein degradation capabilities. However, off-target induced unintended tissue effects and intrinsic “hook effect” hinder PROTAC biotechnology to be maturely developed. Herein, an intracellular fabricated nano proteolysis targeting chimeras (Nano-PROTACs) modality with a center-spoke degradation network for achieving efficient dose-dependent protein degradation in tumor is reported. The PROTAC precursors are triggered by higher GSH concentrations inside tumor cells, which subsequently in situ self-assemble into Nano-PROTACs through intermolecular hydrogen bond interactions. The fibrous Nano-PROTACs can form effective polynary complexes and E3 ligases degradation network with multi-binding sites, achieving dose-dependent protein degradation with “anti-hook effect”. The generality and efficacy of Nano-PROTACs are validated by degrading variable protein of interest (POI) such as epidermal growth factor receptor (EGFR) and androgen receptor (AR) in a wide-range dose-dependent manner with a 95 % degradation rate and long-lasting potency up to 72 h in vitro. Significantly, Nano-PROTACs achieve in vivo dose-dependent protein degradation up to 79 % and tumor growth inhibition in A549 and LNCap xenograft mice models, respectively. Taking advantages of in situ self-assembly strategy, the Nano-PROTACs provide a generalizable platform to promote precise clinical translational application of PROTAC. 相似文献
996.
Minghui Liu Prof. Guigang Zhang Xiaocong Liang Dr. Zhiming Pan Dr. Dandan Zheng Prof. Sibo Wang Prof. Zhiyang Yu Yidong Hou Prof. Xinchen Wang 《Angewandte Chemie (International ed. in English)》2023,62(37):e202304694
In situ photo-deposition of both Pt and CoOx cocatalysts on the facets of poly (triazine imide) (PTI) crystals has been developed for photocatalytic overall water splitting. However, the undesired backward reaction (i.e., water formation) on the noble Pt surface is a spontaneously down-hill process, which restricts their efficiency to run the overall water splitting reaction. Herein, we demonstrate that the efficiency for photocatalytic overall water splitting could be largely promoted by the decoration of Rh/Cr2O3 and CoOx as H2 and O2 evolution cocatalysts, respectively. Results reveal that the dual cocatalysts greatly extract charges from bulk to surface, while the Rh/Cr2O3 cocatalyst dramatically restrains the backward reaction, achieving an apparent quantum efficiency (AQE) of 20.2 % for the photocatalytic overall water splitting reaction. 相似文献
997.
Tong Shen Dr. Ya Zou Dr. Xudong Hou Dr. Haipeng Wei Dr. Longbin Ren Liuying Jiao Prof. Jishan Wu 《Angewandte Chemie (International ed. in English)》2023,62(45):e202311928
Polycyclic aromatic hydrocarbons (PAHs) with a one-dimensional (1D), ribbon-like structure have the potential to serve as both model compounds for corresponding graphene nanoribbons (GNRs) and as materials for optoelectronics applications. However, synthesizing molecules of this type with extended π-conjugation presents a significant challenge. In this study, we present a straightforward synthetic method for a series of bis-peri-dinaphtho-rylene molecules, wherein the peri-positions of perylene, quaterrylene, and hexarylene are fused with naphtho-units. These molecules were efficiently synthesized primarily through intramolecular or intermolecular radical coupling of in situ generated organic radical species. Their structures were confirmed using X-ray crystallographic analysis, which also revealed a slightly bent geometry due to the incorporation of a cyclopentadiene ring at the bay regions of the rylene backbones. Bond lengh analysis and theoretical calculations indicate that their electronic structures resemble pyrenacenes more than quinoidal rylenes. That is, the aromatic sextets are predominantly localized along the long axis of the skeletones. As the chain length increases, these molecules exhibit enhanced electronic absorption with a bathochromic shift, and multiple amphoteric redox waves. This study introduces a novel synthetic approach for generating 1D extended PAHs and GNRs, along with their structure-dependent electronic properties. 相似文献
998.
Yong Hou Jiarong Zhou Xiaoping Liu Linliang Yu Chunlin Ni 《Transition Metal Chemistry》2008,33(4):411-416
Two new salts, [oClBzTPP]2+[Ni(mnt)2]2−(1) and [oClBzTPP]+[Ni(mnt)2]−(2) ([oClBzTPP]+ = 1-(2′-chlorobenzyl)triphenylphosphonium and mnt2− = maleonitriledithiolate) have been prepared and characterized by elemental analyses, UV, IR, MS spectra, single crystal
X-ray diffraction, and magnetic susceptibility. The Ni ions of the Ni(mnt)2 anions for 1 and 2 exhibit the square-planar coordination geometry. The Ni(III) ions of 2 form a 1D zigzag alternating magnetic chain within a Ni(mnt)2− column through Ni···S, S···S, or Ni···Ni interactions. The C–H···N, C–H···S, C–H···π hydrogen bonds or π···π stacking interactions
play important roles in the molecular stabilizing and stacking of 1 and 2. Magnetic susceptibility measurements in the temperature range 1.8−300 K show that 2 exhibits diamagnetic behavior. 相似文献
999.
1000.
Qian S Joo SW Hou WS Zhao X 《Langmuir : the ACS journal of surfaces and colloids》2008,24(10):5332-5340
The electrophoretic motion of a spherical nanoparticle, subject to an axial electric field in a nanotube filled with an electrolyte solution, has been investigated using a continuum theory, which consists of the Nernst-Planck equations for the ionic concentrations, the Poisson equation for the electric potential in the solution, and the Stokes equation for the hydrodynamic field. In particular, the effects of nonuniform surface charge distributions around the nanoparticle on its axial electrophoretic motion are examined with changes in the bulk electrolyte concentration and the surface charge of the tube's wall. A particle with a nonuniform charge distribution is shown to induce a corresponding complex ionic concentration field, which in turn influences the electric field and the fluid motion surrounding the particle and thus its electrophoretic velocity. As a result, contrary to the relatively simple dynamics of a particle with a uniform surface charge, dominated by the irradiating electrostatic force, that with a nonuniform surface charge distribution shows various intriguing behaviors due to the additional interplay of the nonuniform electro-osmotic effects. 相似文献