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31.
Syntheses,Structures, and Luminescent Properties of d10 Coordination Polymers with 2‐(4‐Carboxyphenyl)‐imidazo[4, 5‐f]‐1, 10‐phenanthroline and 1, 3‐Benzenedicarboxylate Derivatives 下载免费PDF全文
Jie‐Fang Fang Jing‐Xiang Cheng Shu‐Ting Huang Jing Zhang Chang‐Qiong Ni Yan‐Ju Xiong Qian Cheng Fei‐Fei Zhu Yun Li Shan‐Tang Yue 《无机化学与普通化学杂志》2015,641(15):2657-2663
Four ZnII/CdII coordination polymers (CPs) based on 2‐(4‐carboxy‐phenyl)imidazo[4, 5‐f]‐1, 10‐phenanthroline (HNCP) and different derivatives of 5‐R‐1, 3‐benzenedicarboxylate (5‐R‐1, 3‐BDC) (R = NO2, H, OH), [Zn(HNCP)(5‐NO2‐1, 3‐BDC)]n ( 1 ), [Cd(HNCP)(5‐NO2‐1, 3‐BDC)]n ( 2 ), [Zn(HNCP)(1, 3‐BDC)(H2O)2]n ( 3 ), and {[Zn(HNCP)(5‐OH‐1, 3‐BDC)(H2O) · H2O}n ( 4 ) were synthesized under hydrothermal conditions. Compounds 1 – 4 were determined by elemental analyses, IR spectroscopy, and single‐crystal and powder X‐ray diffraction. Compounds 1 and 2 are isomorphous, presenting a 4‐connected uninodal (4, 4)‐sql 2D framework with threefold interpenetration, which are further extended into the three‐dimensional (3D) supramolecular architecture through π ··· π stacking interactions between the aryl rings of 5‐NO2‐1, 3‐BDC. Compared to compound 1 , 3 is obtained by using different reaction temperatures and metal‐ligand ratios, generating a 3D framework with –ABAB– fashion via π ··· π stacking interactions. Compound 4 is a 1D chain, which is further extended into a 3D supramolecular net by hydrogen bonds and π ··· π stacking interactions. The thermogravimetric and fluorescence properties of 1 – 4 were also explored. 相似文献
32.
Runyan Ni Naoto Mitsuda Takeru Kashiwagi Kazunobu Igawa Katsuhiko Tomooka 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(4):1206-1210
A variety of medium‐sized cycloalkynes were efficiently synthesized by the double Nicholas reaction of cobalt complex and bis(hetero)substituted acyclic compound. The alkyne moiety within the ring has a unique bent structure and high reactivity toward cycloaddition reactions. Furthermore, preparation of multifunctionalized alkynes was achieved by embedding the cycloalkyne within a peptide chain. 相似文献
33.
Hiroki Hirai Kiichi Nakajima Soichiro Nakatsuka Kazushi Shiren Jingping Ni Shintaro Nomura Toshiaki Ikuta Takuji Hatakeyama 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(46):13785-13789
The development of a one‐step borylation of 1,3‐diaryloxybenzenes, yielding novel boron‐containing polycyclic aromatic compounds, is reported. The resulting boron‐containing compounds possess high singlet‐triplet excitation energies as a result of localized frontier molecular orbitals induced by boron and oxygen. Using these compounds as a host material, we successfully prepared phosphorescent organic light‐emitting diodes exhibiting high efficiency and adequate lifetimes. Moreover, using the present one‐step borylation, we succeeded in the synthesis of an efficient, thermally activated delayed fluorescence emitter and boron‐fused benzo[6]helicene. 相似文献
34.
A new fluorescent quenching method for the determination of phosphoproteins by using calconcarboxylic acid 下载免费PDF全文
Zhongxin Zhu Xinliang Zhu Jiayi Shen Ayi Zhou Maowei Ni Litai Jin Weitao Cong 《Electrophoresis》2015,36(6):924-929
A fluorescent quenching detection method for phosphoproteins in SDS‐PAGE by using calconcarboxylic acid (CCA) was described. In this method, the fluorescence intensity of CCA was greatly increased with the presence of Al3+ in the gel background, while in zones where phosphoproteins are located this intensity was absent because of fluorescence quenching phenomenon through the formation of CCA‐Al3+‐phosphoprotein appended complex. Approximately 4–8 ng of phosphoproteins can be selectively detected within 1 h (1D SDS‐PAGE), which is similar to that of the most commonly used Pro‐Q Diamond stain. The specificity of this novel technique for phosphoproteins was confirmed by dephosphorylation, Western blot, and LC‐MS/MS analysis, respectively. Furthermore, to better understand the newly developed method, the detection mechanism of CCA stain was explored by fluorescent spectrometry. According to the results, it is believed that CCA stain may provide a new choice for selective, economical, MS compatible, and convenient visualization of gel‐separated phosphoproteins. 相似文献
35.
Screening of drugs of abuse and toxic compounds in human whole blood using online solid‐phase extraction and high‐performance liquid chromatography with time‐of‐flight mass spectrometry 下载免费PDF全文
Xiaomei Teng Chen Liang Rong Wang Tao Sun Yulan Rao Chunfang Ni Libo Zeng Lingjuan Xiong Yuan Li Yurong Zhang 《Journal of separation science》2015,38(1):50-59
A novel method for the screening of 151 drugs of abuse and toxic compounds in human whole blood has been developed and validated by online solid‐phase extraction with liquid chromatography coupled to time‐of‐flight mass spectrometry. Analytes were extracted and separated by using a fully automated online solid‐phase extraction liquid chromatography system with total chromatographic run time of 26 min. Time‐of‐flight mass spectrometry screening of 151 drugs of abuse and toxic compounds was performed in a full‐scan (m/z 50–800) mode using an MSE acquisition of molecular ions and fragment ions data at two collision energies (one was 6 eV and another one was in the range of 5–45 eV). The compounds were identified based on retention times and exact mass of molecular ions and fragment ions. The limit of detection ranged from 1 to 100 ng/mL and the recovery of the method ranged from 6.3 to 163.5%. This method is proved to be a valuable screening method allowing fast and specific identification of drugs in human whole blood. 相似文献
36.
Automated headspace solid‐phase microextraction and on‐fiber derivatization for the determination of clenbuterol in meat products by gas chromatography coupled to mass spectrometry 下载免费PDF全文
A method was developed for the determination of clenbuterol in meat using stable‐isotope‐dilution gas chromatography with mass spectrometry coupled with solid‐phase microextraction and on‐fiber derivatization. The samples were first homogenized with hydrochloric acid followed by protein deposition. After headspace solid‐phase microextraction and on‐fiber derivatization, the content of clenbuterol was measured with the aid of stable‐isotope dilution. The condition of solid‐phase microextraction was optimized by central composite design. The relative standard deviations, limit of detection, and recoveries for clenbuterol were 4.2–9.2%, 0.48 μg/kg, and 96–104%, respectively. The proposed method was satisfactory for analysis of real samples as compared with the Chinese standard method. 相似文献
37.
心血管疾病(CVD)是全球最主要的死亡原因,急性心肌梗死(AMI)是心血管疾病致死的主要病因,安全快速地诊断AMI对于降低患者的死亡率至关重要。因常用的检测方法如心电图(ECG)缺乏足够的敏感性,寻找并针对AMI生物标志物开展高灵敏检测已成为早期检测AMI重要手段。心肌肌钙蛋白I(cTnI)、肌酸激酶同工酶(CK-MB)和肌红蛋白(Myo)是目前公认的检测AMI的重要心肌生物标志物。在过去的几十年里,许多生物传感器被开发出来用于检测心肌生物标志物,其中基于表面增强拉曼光谱(SERS)的心肌生物标志物检测技术迅速发展,并表现出独特的技术优势和广阔的应用前景。本文首先介绍了多种心肌生物标志物及其与AMI的关联,在此基础上概述主要的心肌生物标志物检测方法的原理、优势及局限性,重点介绍近年来新兴的SERS技术及其在心肌生物标志物传感方面的最新研究进展,并对该技术在AMI诊断方面的应用前景以及有待突破的瓶颈进行了讨论和展望。 相似文献
38.
Efficient,robust and cost-effective electrocatalysts that catalyze hydrogen evolution/oxidation reaction(HER/HOR)in alkaline media are highly demanded.Recently,single-atom catalysts(SACs)have emerged as new promising candidates;however,the rational design of supports and the optimization of coordination environment between supports and metal atoms are challenging.In this work,we successfully fabricate atomically dispersed ruthenium(Ru)species,which are strongly coordinated by N and S dual heteroatoms on holey graphene(RuSA/NSG),as an excellent bifunctional catalyst for HER/HOR.In alkaline media,the developed catalyst exhibits high catalytic performance with a low overpotential of 57.3 mV to drive a current density of 10 mA cm-1 for HER,and its mass activity is about 5.8 times higher than that of commercial Pt/C and Ru/C catalysts at an overpotential of 100 mV.Similarly,considerable HOR performance of Ru SA/NSG is verified to be superior to Pt/C and Ru/C.Furthermore,X-ray-based spectroscopy measurements and density-functional theory calculations have confirmed that,compared with Ru–N4,the tailored Ru–N4–S2 with nearby S dopants can act as more active centers to greatly accelerate the sluggish HER/HOR kinetics in alkaline media.The present work provides a new atomic-level engineering strategy to modulate catalytic activities of SACs via the coordination design using dual heteroatoms on the carbon support. 相似文献
39.
Alam Nur Tong Li He Zhibin Tang Ruihua Ahsan Laboni Ni Yonghao 《Cellulose (London, England)》2021,28(13):8641-8651
Cellulose - Lateral flow assay (LFA) is an important point-of-care (POC) test platform due to the associated portability, on-site testing, and low cost for diagnosis of pathogen infections and... 相似文献
40.