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A novel triazole fluorescent sensor was efficiently synthesized using binaphthol as the starting substrate with 85% total end product yield. This chiral fluorescence sensor was proved to have high specific enantioselectivity for lysine. The fluorescence intensity of R-1 was found to increase linearly when the equivalent amount of L-lysine (0–100 eq.) was gradually increased in the system. The fluorescence intensity of L-lysine to R-1 was significantly enhanced, accompanied by the red-shift of emission wavelength (389 nm to 411 nm), which was attributed to the enhanced electron transfer within the molecular structure, resulting in an ICT effect, while the fluorescence response of D-lysine showed a decreasing trend. The enantioselective fluorescence enhancement ratio for the maximum fluorescence intensity was 31.27 [ef = |(IL − I0)/(ID − I0)|, 20 eq. Lys], thus it can be seen that this fluorescent probe can be used to identify and distinguish between different configurations of lysine. [ABSTRACT FROM AUTHOR]

[Display omitted] • An ultra-long carbon-chain salamo-like probe DNS was synthesized. • The probe DNS molecule has efficient and specific recognition for CO 3 2−. • The minimum detection limit of the fluorescent probe DNS is superior to other reported methods. A novel extra-long carbon-chain salamo-like fluorescent chemical probe DNS (named as 2,2′-[1,10-(decanedioxy)bis(nitromethyldyne)]dinaphthol) containing ten methylene groups was synthesized based on the 2-hydroxy-1-naphthylaldehyde unit. Research has shown that the fluorescent probe DNS can achieve efficient and selective recognition of CO 3 2− anions, with a detection limit LOD=1.59 × 10−8 M. The binding constant Ka = 3.7 × 104 M−1 and quantification limit is as low as LOQ=4.31 × 10−8 M, respectively. The possible identification mechanism of the fluorescent chemosensor DNS was analyzed and studied through fluorescence titration and nuclear magnetic titration. The results showed that the fluorescence chemical sensor DNS is deprotonated by CO 3 2− anions, enhancing its fluorescence and producing a ICT effect. [ABSTRACT FROM AUTHOR]

• A salamo-type probe NJS was designed and synthesized. • The probe NJS was used to detect B 4 O 7 2− ions by colorimetric and fluorescence dual-channel. • The probe NJS can detect B 4 O 7 2− ions in real water samples. • The NJS probe can be mounted on a portable test strip as well as a swab for the actual testing of B 4 O 7 2− ions. A novel yet facile dual-channel salamo-type fluorescent probe NJS was synthesized successfully in this study. The probe NJS can efficiently detect B 4 O 7 2− ions through colorimetric and fluorescent dual channels. Under sunlight, when B 4 O 7 2− ionic solution was added to NJS solution, the mixed solution became a distinct yellow color, in sharp contrast to other anions. The fluorescence detection results showed that fluorescence strength of probe NJS is increased in a short time with the increasement of B 4 O 7 2− ion content. In addition, the detection limit LOD of probe NJS for B 4 O 7 2− ions was 2.81 × 10−8 M and the binding constant Ka was 2.20 × 104 M −1 by fluorescence titration. According to nuclear magnetic titration and relevant DFT calculations, it was speculated that after adding B 4 O 7 2− ions into the probe solution, the probe NJS is deprotonated, triggering ICT and FRET effect, resulting in an increase of fluorescence intensity accompanied by redshift, and achieving the specific recognition of B 4 O 7 2− ions by probe NJS. Finally, the practical application of probe NJS was studied. It was found that the probe can be used for qualitative and quantitative analysis of B 4 O 7 2− ions through swab, paper test and actual water sample experiments. [ABSTRACT FROM AUTHOR]

Information and communication technologies (ICTs) may have a significant impact on education in general and mathematics education in particular, with greater access to open learning sources, widespread interaction through online and social networking, and the availability of a variety of teaching and learning tools. However, these benefits of using ICTs in mathematics teaching and learning should be materialized both by teachers and students at the individual and institutional level with application skills. This study aimed to explore the interrelation between teachers ' perceptions of using ICTs in mathematics teaching-learning and the learners' performance in mathematics. An online survey was administered among mathematics teachers with an open invitation through social media, and 410 mathematics teachers from school to university level responded to the questionnaire. The Mann-Whitney, Kruskal Wallis, and structural equation modeling were the primary statistical techniques used in the research. The results showed six critical factors of JCT-related issues related to adjusting learning experiences, inspiration and motivational strategies for learners, learning support, sharing and communication, evaluation/self-assessment for learning, and collaboration which impacted students ' mathematics performance. The types of institutions and availability of smartboardslwhiteboards in the classrooms significantly contributed to students ' performance in mathematics. [ABSTRACT FROM AUTHOR]

In this contribution, a unique donor‐acceptor conjugated organic‐small‐molecule photothermal material, namely GDPA‐QCN, is presented. Bulky dendritic triphenylamine (GDPA) was grafted onto quinoxaline‐6,7‐dicarbonitrile (QCN) with a phenyl ring as a bridge to form an "umbrella" architecture. Benefited from the particular molecular structure, in solid state, GDPA‐QCN molecules adopted a loose packing mode due to the steric effect of "umbrella head" dendritic triphenylamine and flexible molecular structure feature, which allows efficient intramolecular motions and consequently elevates energy dissipation by taking the pathway of thermal deactivation within broad absorption range. The GDPA‐QCN solid has high solar‐thermal conversion efficiency with an absorption range from 300 to 1100 nm, which can promote superior water purification and electricity generation performance. [ABSTRACT FROM AUTHOR]

A novel triazole fluorescent sensor was efficiently synthesized using binaphthol as the starting substrate with 85% total end product yield. This chiral fluorescence sensor was proved to have high specific enantioselectivity for lysine. The fluorescence intensity of R-1 was found to increase linearly when the equivalent amount of L-lysine (0–100 eq.) was gradually increased in the system. The fluorescence intensity of L-lysine to R-1 was significantly enhanced, accompanied by the red-shift of emission wavelength (389 nm to 411 nm), which was attributed to the enhanced electron transfer within the molecular structure, resulting in an ICT effect, while the fluorescence response of D-lysine showed a decreasing trend. The enantioselective fluorescence enhancement ratio for the maximum fluorescence intensity was 31.27 [ef = |(IL − I0)/(ID − I0)|, 20 eq. Lys], thus it can be seen that this fluorescent probe can be used to identify and distinguish between different configurations of lysine.

Two novel coumarin derivatives and the corresponding europium complexes were prepared using a simple procedure. The pH response of the ligand and the aggregation‐induced emission (AIE) properties of the target europium complex were studied. The ligand had an intramolecular charge transfer (ICT) effect and was linearly and sharply responsive under acidic conditions. The goal europium complexes exhibited excellent AIE performance when subjected to increasing concentrations of target europium complex or proportion of poor solvent. The effect of substituents on fluorescence strength or thermogravimetric and electrochemical properties was further investigated. The target complexes displayed the typical fluorescence of europium. The fluorescence amplitude of the target europium complexes was enhanced by the addition of electron‐donating groups to ligands. Thermogravimetric research findings indicated that the target complexes possessed extreme thermal stability. Electrochemistry discovery findings indicated that the highest occupied molecular orbit energy level of EuL1 was greater than EuL2, but the lowest unoccupied molecular orbit energy level was smaller than that of EuL2. These complexes could be applied in medicinal chemistry, substance chemistry, and fluorescence labelling areas. [ABSTRACT FROM AUTHOR]

The aim of this article is to investigate the potential influence of the use of Information and Communication Technologies (ICTs) on the organizational structures of entities in contemporary collective action space. In order to do so, the article adopts the collective action space model offered by Bimber, Flanagin and Stohl to analyse the relationship between communicational activities and the organizational characteristics of four different organizations that were actively involved in the Gezi Movement (2013) in Turkey. Specifically, using data collected through in-depth interviews and participant observations, the article focuses on the engagement structures and interaction forms of these four organizations. The findings from this study suggest not only that ICTs allow organizations to become more structurally complex and dynamic but also that the manner in which ICTs are used for interactions and governance plays a critical role in the transformation of the structure of organizations in collective action space. [ABSTRACT FROM AUTHOR]

In order to explore the application of D-π-A molecules in bio-imaging, two novel D-π-A and ICT type molecules (SE and PE) are designed and synthesized by the adjustment of the π conjugation bridge. Because of strong intramolecular charge transfer (ICT) effect between the carbazole and pyrimidine unit, SE and PE exhibit weak fluorescence emission in the aqueous solution system. Interestingly, SE shows the enhanced fluorescence detection performance for hypochlorite due to "D-π-A" structure and suitable ICT effect after the oxidative cleavage of alkene unit by hypochlorite. Importantly, the cell membrane permeable SE can be used for the exogenous and endogenous ClO− in living cells and zebrafishes without apparent toxicity before and after treating with ClO−. Our study indicates that regulating "D-π-A" structure and suitable ICT effect of the organic fluorescence probes is a powerful method to enhance their detection performance for the target analyte. • D-π-A and ICT fluorescent probe (SE) was designed and prepared. • SE showed significant fluorescence changes from weak to strong green in the presence of ClO− due to the ICT effect. • SE was applied to detect exogenous and endogenous ClO− in living cells and zebrafish. [ABSTRACT FROM AUTHOR]

Two novel coumarin derivatives and the corresponding europium complexes were prepared using a simple procedure. The pH response of the ligand and the aggregation-induced emission (AIE) properties of the target europium complex were studied. The ligand had an intramolecular charge transfer (ICT) effect and was linearly and sharply responsive under acidic conditions. The goal europium complexes exhibited excellent AIE performance when subjected to increasing concentrations of target europium complex or proportion of poor solvent. The effect of substituents on fluorescence strength or thermogravimetric and electrochemical properties was further investigated. The target complexes displayed the typical fluorescence of europium. The fluorescence amplitude of the target europium complexes was enhanced by the addition of electron-donating groups to ligands. Thermogravimetric research findings indicated that the target complexes possessed extreme thermal stability. Electrochemistry discovery findings indicated that the highest occupied molecular orbit energy level of EuL 1 was greater than EuL 2 , but the lowest unoccupied molecular orbit energy level was smaller than that of EuL 2 . These complexes could be applied in medicinal chemistry, substance chemistry, and fluorescence labelling areas., (© 2020 John Wiley & Sons, Ltd.)