CRISPR-Cas12a System for Biosensing and Gene Regulation

Clustered regularly interspaced short palindromic repeats (CRISPR) is a promising technology in the biological world. As one of the CRISPR-associated (Cas) proteins, Cas12a is an RNA-guided nuclease in the type V CRISPR-Cas system, which has been a robust tool for gene editing. In addition, due to the discovery of target-binding-induced indiscriminate single-stranded DNase activity of Cas12a, CRISPR-Cas12a also exhibits great promise in biosensing. This minireview not only gives a brief introduction to the mechanism of CRISPR-Cas12a but also highlights the recent developments and applications in biosensing and gene regulation. Finally, future prospects of the CRISPR-Cas12a system are also discussed. We expect this minireview will inspire innovative work on the CRISPR-Cas12a system by making full use of its features and advantages.     

Syntheses,Characterization, and Luminescence Properties of Three Coordination Complexes with Sulfonate-Phenol Anions and Trivalent Metal Ions

Russian Journal of General Chemistry - A dinuclear Tb complex, Tb2(H2L)3(phen)2 (1), and two similar N-donor coordination complexes, Fe(phen)3·HL (2), Fe(bipy)3·HL·5H2O (3) (Na2H2L =...     

Quantum Windowed Fourier Transform and its Application to Quantum Signal Processing

International Journal of Theoretical Physics - In classical information processing, the windowed Fourier transform (WFT), or short-time Fourier transform, which is a variant of the Fourier...     

基于吸收互补有机半导体本体复合薄膜的高性能柔性光突触晶体管

采用光吸收互补的聚(3-己基噻吩)(P3HT)和引达省并二噻吩-苯并噻二唑共聚物(PIDT-BT), 通过溶液法制备了两者的本体复合异质结构有机半导体薄膜, 并研究了薄膜的表面结构和光电性质. 将PIDT-BT:P3HT复合薄膜作为一类新型光敏沟道层, 与聚电解质介电材料相结合, 制备了高性能柔性低电压光突触晶体管. 考察了不同光刺激条件对光突触晶体管性能的影响及半导体机制, 发现PIDT-BT:P3HT器件具有明显光突触特性, 并且相较于单纯PIDT-BT或P3HT器件具有更高响应的兴奋性突触后电流. 基于PIDT-BT:P3HT薄膜的光突触器件, 在绿红双色光刺激下的响应大于两种单色光分别刺激的响应之和, 表明附加光刺激可调控器件的记忆效率. 该研究为发展高性能光响应半导体薄膜及柔性低功耗光突触器件提供了新策略.     

A simple and rapid route for synthesizing the nanosized g-C3N4 materials with narrow bandgap and their photocatalytic activity

The graphitic carbon nitride (g-C₃N₄) materials with many intriguing properties have attracted much attention in photocatalysis. The photocatalytic activity of g-C₃N₄ is hindered by serious aggregation and limited exposed active sites. Herein is shown that nanosized g-C₃N₄ can be simply obtained by a superfast high-pressure homogenization approach. The high-pressure homogenization treatment can provide strong force to cut and/or to exfoliate the bulk g-C₃N₄ into nanosized g-C₃N₄ with good dispersion. Moreover, choosing different solvents during treatment can cause a different surface structure of as-prepared nanosized g-C₃N₄. In addition, the narrow bandgap properties, the high photogenerated charge carrier separation, and the transport abilities are achieved in as-prepared nanosized g-C₃N₄ because of the retaining conjugated C₃N₄ system. Specifically, the photocatalytic activities of as-prepared nanosized g-C₃N₄ have been significantly enhanced in terms of degradation of organic dye Rhodamine B (RhB) under visible light irradiation (10 times higher than that of bulk g-C₃N₄). These findings can provide a promising and simple approach to the exfoliation, nanonization, and surface functionalization of 2D layered materials.     

指纹物质中毒品检测的研究进展

指纹作为案件现场中最常见的物证之一,不仅包含了可用于人身识别的形态特征,还蕴含了丰富的反映遗留人人身特点的化学信息。通过对指纹中毒品物质的检测及分析,可提供指纹遗留者毒品的吸食、接触情况,将其与特定案件相联系,反映个人生活方式信息,为涉毒人员的发现提供新思路。该文利用文献计量学方法总结了该领域的发展脉络以及研究现状与热点,主要总结了目前已建立的指纹物质中毒品分析检测的各种技术方法和特点,并对未来研究方向及难点进行评述,以期为实际案件指纹中的毒品检测提供参考。     

Highly Active Hydrogen-rich Photothermal Reverse Water Gas Shift Reaction on Ni/LaInO3 Perovskite Catalysts with Near-unity Selectivity

Photo-assisted reverse water gas shift (RWGS) reaction is regarded green and promising in controlling the reaction gas ratio in Fischer Tropsch synthesis. But it is inclined to produce more byproducts in high H₂ concentration condition. Herein, LaInO₃ loaded with Ni-nanoparticles (Ni NPs) was designed to obtain an efficient photothermal RWGS reaction rate, where LaInO₃ was enriched with oxygen vacancies to roundly adsorbing CO₂ and the strong interaction with Ni NPs endowed the catalysts with powerful H₂ activity. The optimized catalyst performed a large CO yield rate (1314 mmol g_Ni⁻¹ h⁻¹) and ≈100 % selectivity. In situ characterizations demonstrated a COOH* pathway of the reaction and photoinduced charge transfer process for reducing the RWGS reaction active energy. Our work provides valuable insights on the construction of catalysts concerning products selectivity and photoelectronic activating mechanism on CO₂ hydrogenation.     

In Situ Polymerized 1,3-Dioxolane Electrolyte for Integrated Solid-State Lithium Batteries

Solid-state lithium batteries are promising and safe energy storage devices for mobile electronics and electric vehicles. In this work, we report a facile in situ polymerization of 1,3-dioxolane electrolytes to fabricate integrated solid-state lithium batteries. The in situ polymerization and formation of solid-state dioxolane electrolytes on interconnected carbon nanotubes (CNTs) and active materials is the key to realizing a high-performance battery with excellent interfacial contact among CNTs, active materials and electrolytes. Therefore, the electrodes could be tightly integrated into batteries through the CNTs and electrolyte. Electrons/ions enable full access to active materials in the whole electrode. Electrodes with a low resistance of 4.5 Ω □⁻¹ and high lithium-ion diffusion efficiency of 2.5×10⁻¹¹ cm² s⁻¹ can significantly improve the electrochemical kinetics. Subsequently, the batteries demonstrated high energy density, amazing charge/discharge rate and long cycle life.     

Hybrid Double Perovskite Derived Halides Based on Bi and Alkali Metals (K,Rb): Diverse Structures,Tunable Optical Properties and Second Harmonic Generation Responses

Double perovskites (DP) have attracted extensive attention due to their rich structures and wide application prospects in the field of optoelectronics. Here, we report 15 new Bi-based double perovskite derived halides with the general formula of A₂BBiX₆ (A=organic cationic ligand, B=K or Rb, X=Br or I). These materials are synthesized using organic ligands to coordinate with metal ions with a sp³ oxygen, and diverse structure types have been obtained with distinct dimensionalities and connectivity modes. The optical band gaps of these phases can be tuned by changing the halide, the organic ligand and the alkali metal, varying from 2.0 to 2.9 eV. The bromide phases exhibit increasing photoluminescence (PL) intensity with decreasing temperature, while the PL intensity of iodide phases changes nonmonotonically with temperature. Because the majority of these phases are non-centrosymmetric, second harmonic generation (SHG) responses are also measured for selected non-centrosymmetric materials, showing different particle-size-dependent trends. Our findings give rise to a series of new structural types to the DP family, and provide a powerful synthetic handle for symmetry breaking.