Synthesis of cyanine dyes derived from benzotellurazo‐15‐crown‐5

A series of crown ether cyanine dyes including crown ether styryl cyanine dyes, crown ether merocyanine dyes and crown ether squarylium cyanine dyes (unsymmetric and symmetric) derived from key intermediate 2‐methyl‐5,6(15‐crown‐5)benzotellurazole ( 1 ) were prepared.     

Multiphoton Ionization Spectra of Yb Atom in Electric Fields

1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　　Ｔｈｅｔｒａｎｓｉｔｉｏｎｐｒｏｐｅｒｔｉｅｓｏｆｈｉｇｈｌｙ ｅｘｃｉｔｅｄｓｔａｔｅｓｏｆＹｂａｔｏｍｈａｖｅｂｅｅｎｏｎｅｏｆｔｈｅｍｏｓｔｅｘｔｅｎｓｉｖｅｌｙｓｔｕｄｉｅｄｓｕｂｊｅｃｔｓｆｏｒｔｈｅｌａｓｔｄｅｃａｄｅｓ[1～ 6 ] .Ｉｎｐａｒｔｉｃｕｌａｒ,ｓｏｍｅａｓｐｅｃｔｓｏｆｔｈｉｓｓｕｂｊｅｃｔ,ｓｕｃｈａｓｐｏｓｉｔｉｏｎｓａｎｄｓｔｒｕｃｔｕｒｅｓｏｆｔｈｅｈｉｇｈｌｙ ｅｘｃｉｔｅｄｓｔａｔｅｓ,ａｒｅｓｔｕｄｉｅｄｓｙｓｔｅｍａｔｉｃａｌｌｙ…     

Solvable line-transitive automorphism groups of finite linear spaces

Let S be a finite linear space, and letG be a group of automorphisms of S. IfG is soluble and line-transitive, then for a givenk but a finite number of pairs of (S, G),S hasv= p ⁿ points andG ⩽AΓL(1,p ⁿ ).     

1.31μm附近水汽分子的自加宽系数、氮气加宽系数的测量

采用窄线宽二极管激光器与1 km的怀特池相结合来提高光谱探测灵敏度,最小可探测谱线吸收强度为10-27cm-1/(molecule.cm-2)。根据记录的光谱数据精确计算出7599~7616 cm-1波段内水汽分子的谱线强度、自加宽系数和氮气加宽系数,实验结果与HITRAN96和HITRAN2004数据库进行了比较,存在一些差异。测量的谱线参量与HITRAN96相接近,与HITRAN2004相差较大,有7条HITRAN96中没有的新谱线被观测,有5条在HITRAN2004数据库中被证实,另外观测到2条谱线在HITRAN96中被列出,而在HITRAN2004没有给出。     

Single-Atom Nanozymes: Fabrication,Characterization, Surface Modification and Applications of ROS Scavenging and Antibacterial

Nanozymes are nanomaterials with intrinsic natural enzyme-like catalytic properties. They have received extensive attention and have the potential to be an alternative to natural enzymes. Increasing the atom utilization rate of active centers in nanozymes has gradually become a concern of scientists. As the limit of designing nanozymes at the atomic level, single-atom nanozymes (SAzymes) have become the research frontier of the biomedical field recently because of their high atom utilization, well-defined active centers, and good natural enzyme mimicry. In this review, we first introduce the preparation of SAzymes through pyrolysis and defect engineering with regulated activity, then the characterization and surface modification methods of SAzymes are introduced. The possible influences of surface modification on the activity of SAzymes are discussed. Furthermore, we summarize the applications of SAzymes in the biomedical fields, especially in those of reactive oxygen species (ROS) scavenging and antibacterial. Finally, the challenges and opportunities of SAzymes are summarized and prospected.     

CO2分子的近红外二极管激光吸收光谱灵敏探测

利用近红外二极管激光波长调制技术与二次谐波探测结合初步观测了CO2 分子在波长 1.5 7μm附近的吸收 ,获得了最小可探测吸收为 8.6× 10 -5(信噪比为 2 ) ,对应 5 0 0× 10 -6m-1的探测灵敏度。     

有限光束相位共轭实时大气湍流补偿实验

报道了在距地面４ｍ高的１０００ｍ水平传输通道上,通过改变光束的尺寸研究取样孔径对相位共轭补偿特性的影响。研究结果表明,补偿效果及峰值光强与取样孔径有关,并且存在最佳取样孔径。     

基于外差法的光纤激光器相干合成

采用波长1064 nm,功率为1 W的种子激光实现了两路光纤激光的相干合成,采用了两只保偏光纤准直器接收两路光干涉信号,与利用透镜直接把干涉信号会聚在探测器上相比,这种耦合方式得到的光干涉信号的条纹对比度更高。对相位噪声以及相位噪声的带宽进行了研究,结果表明,相位噪声由电信号串扰以及环境扰动产生。通过人为拨动光纤来增加相位噪声带宽,当相位噪声带宽增加时,相位控制精度下降。提出了提高相位控制精度的方法,实验获得了桶中功率为21.3%、斯特列尔比为79%、相位控制精度为0.008的相干合成效果。     

Maslinic Acid: A New Compound for the Treatment of Multiple Organ Diseases

Maslinic acid (MA) is a pentacyclic triterpene acid, which exists in many plants, including olive, and is highly safe for human beings. In recent years, it has been reported that MA has anti-inflammatory, antioxidant, anti-tumor, hypoglycemic, neuroprotective and other biological activities. More and more experimental data has shown that MA has a good therapeutic effect on multiple organ diseases, indicating that it has great clinical application potential. In this paper, the extraction, purification, identification and analysis, biological activity, pharmacokinetics in vivo and molecular mechanism of MA in treating various organ diseases are reviewed. It is hoped to provide a new idea for MA to treat various organ diseases.     

Engineering molecular self-assembly of theranostic nanoprobes for dual-modal imaging-guided precise chemotherapy

Science China Chemistry - Uniting dual-modality of fluorescence and photoacoustic (PA) imaging into theranostic nanoprobes is imperative for spatio-temporally tracking of drug delivery,...