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1 – 10 of 574
Article
Publication date: 1 March 2023

Yuzhen Zhao, Mingxu Zhao, Huimin Zhang, Xiangrong Zhao, Yang Zhao, Zhun Guo, Jianjing Gao, Cheng Ma and Yongming Zhang

This paper aims to prepare third-order nonlinear optical (NLO) organic materials with large nonlinear optimization value, high damage threshold and ultrafast response time.

Abstract

Purpose

This paper aims to prepare third-order nonlinear optical (NLO) organic materials with large nonlinear optimization value, high damage threshold and ultrafast response time.

Design/methodology/approach

A series of novel symmetric and asymmetric compounds possessing third-order NLO properties were synthesized using 1,3,5-tribromobenzene as the basis. The photophysical and electrochemical properties, as well as the click reactions, were characterized by means of UV–VIS–NIR absorption spectroscopy and cyclic voltammetry.

Findings

The donor–acceptor chromophores were inserted into compound, making the molecule to have a broader absorption in the near-infrared regions and a narrower optical and electrochemical band gap. It also formed an electron-delocalized organic system, which has larger effects on achieving a third-order NLO response. The third-order NLO phenomenon of benzene ring complexes was experimentally studied at 532 nm using Z-scan technology, and some compounds showed the expected NLO properties.

Originality/value

The click products exhibit more NLO phenomena by performing different click combinations to the side groups, opening new perspectives on using the system in a variety of photoelectric applications.

Details

Pigment & Resin Technology, vol. 53 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 9 April 2020

Hao Zhou, Kai Zhang, Lin Zhang, Jiamin Lu, Jin Li, Daquan Zhang and Lixin Gao

The authors have prepared the triazole film on copper surface by click reaction and explored its inhibition mechanism.

Abstract

Purpose

The authors have prepared the triazole film on copper surface by click reaction and explored its inhibition mechanism.

Design/methodology/approach

The protective film is assembled by immersing bronze in solution containing p-toluenesulfonyl azide (TA) and propiolic acid (PA).

Findings

Fourier transform infrared spectroscopy (FT-IR) indicates that triazole (TTP) film was formed on bronze surface via click chemistry reaction between TA and PA. It shows TTP film has a good protection for bronze in the atmospheric environment simulation solution. Quantum chemical calculation (QC) and molecule dynamics simulation suggests TTP molecule adsorbs on bronze surface via N and O.

Originality/value

This is beneficial to develop the corrosion inhibitors for the corroded copper alloys.

Details

Anti-Corrosion Methods and Materials, vol. 67 no. 3
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 22 April 2020

Libin Yang, Dong Wang, Hong Gao, Hui Cao, Yuzhen Zhao, Zongcheng Miao, Zhou Yang and Wanli He

This study aims to develop a new kind of functional low molecular weight organic dyes, which is highly efficient, meanwhile inexpensive and easily prepared and modified and can be…

Abstract

Purpose

This study aims to develop a new kind of functional low molecular weight organic dyes, which is highly efficient, meanwhile inexpensive and easily prepared and modified and can be used in photoacoustic (PA) imaging and photothermal therapy (PTT). To further realize the release of molecules under the biomedical condition, the releasing efficiency of micellar nanoparticles under different stimuli were represented.

Design/methodology/approach

A class of azo and Schiff base derivatives with different click reagents were characterized by PA imaging and photothermal (PT) experiments. The molecule with best PT effect was loaded into a temperature-stimuli-sensitive amphiphilic block copolymer which demonstrated the capability of releasing the polymers under the near-infrared (NIR) light of 650 nm.

Findings

The PA and PT effects of a series of azo and Schiff base derivatives with different click reagents were characterized. Introducing the click reagent F4-TCNQ can result in red shift of peaks of PA intensity. Stimulated with 650 nm laser irradiation, the polymer processed higher release rate than being stimulated by temperature stimuli.

Practical implications

This paper not only guides the design of NIR dyes with good PA intensity but also provides a method which has great potential for the application of NIR photothermal dyes in the field of biotechnology for controlled release.

Originality/value

This paper uses click reagents to modify azo and Schiff derivatives and an amphiphilic block copolymer under NIR light to realize controlled release.

Details

Pigment & Resin Technology, vol. 49 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 18 October 2021

Shuchen Tian, Hui Cao, Zhou Yang, Yuzhen Zhao, Wanli He and Hong Gao

Currently, conjugated nonlinear optical (NLO) materials suffer from the drawbacks of complex manufacturing process and high cost. To further study the NLO materials with…

Abstract

Purpose

Currently, conjugated nonlinear optical (NLO) materials suffer from the drawbacks of complex manufacturing process and high cost. To further study the NLO materials with cost-effective, it is necessary to prepare new NLO materials with satisfactory performance.

Design/methodology/approach

Pyrene derivatives with good third-order NLO properties were synthesized by combining pyrene compounds with TCNE, TCNQ, F4-TCNQ and other molecular systems by clicking chemical method.

Findings

The pyrene derivatives were characterized by ultraviolet spectrum and Z-scan. The charge-transfer of the D-p-A structures plays a key role in the absorption peak shifts. And the third-order nonlinear absorption of the products revealed good third-order NLO susceptibilities.

Research limitations/implications

The synthesis technology of pyrene derivatives is not mature enough and is in the preliminary exploration stage. So, the authors produced a relatively small number of samples and did not conduct a very comprehensive test.

Practical implications

This novel pyrene derivative is suggestive and can promote the exploration and development of the third-order nonlinear materials.

Originality/value

Four new pyrene derivatives were synthesized by selecting new molecular systems. Because of its good chemical properties and stable properties, it can be a reference for the development of third-order nonlinear materials in the future.

Article
Publication date: 2 September 2019

Aziz Boutouil, My Rachid Laamari, Ilham Elazhary, Hafid Anane, Abdeslem Ben Tama and Salah-Eddine Stiriba

This study aims to investigate the inhibition effect of a newly synthesized1,2,3-triazole containing a carbohydrate and imidazole substituents, namely…

110

Abstract

Purpose

This study aims to investigate the inhibition effect of a newly synthesized1,2,3-triazole containing a carbohydrate and imidazole substituents, namely, 1-((1-((2,2,7,7-tetramethyltetrahydro-5H-bis([1,3]dioxolo)[4,5-b:4′,5′-d]pyran-5-yl)methyl)-1H-1,2,3-triazol-4-yl)methyl)-1H-benzo[d]imidazole (TTB) on the corrosion of mild steel in aerated 1 M H2SO4.

Design/methodology/approach

The authors have used weight loss measurement, potentiodynamic polarization, electrochemical impedance spectroscopy, FT-IR studies, scanning electron microscopy analysis and energy dispersive X-ray (EDX) spectroscopy techniques.

Findings

It is found that, in the working range of 298-328 K, the inhibition efficiency of TTB increases with increasing concentration to attain the highest value (92 per cent) at 2.5 × 10−3 M. Both chemisorption and physisorption of TTB take place on the mild steel, resulting in the formation of an inhibiting film. Computational methods point to the imidazole and phenyl ring as the main structural parts responsible of adsorption by electron-donating to the steel surface, while the triazol ring is responsible for the electron accepting. Such strong donating–accepting interactions lead to higher inhibition efficiency of TTB in the aqueous working system.

Originality/value

This work is original with the aim of finding new acid corrosion inhibitors.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 6
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 16 October 2017

Yvette Taminiau and Stefan Heusinkveld

Tenders are generally considered important in auditing research and practice, and are associated with significant difficulties for the auditing profession, as well as for…

1621

Abstract

Purpose

Tenders are generally considered important in auditing research and practice, and are associated with significant difficulties for the auditing profession, as well as for individual auditors in the context of client relationships. The purpose of this paper is to explore the way auditors respond to complex client expectations related to the audit tendering process.

Design/methodology/approach

Using a role-theory perspective, the authors analyzed 75 client evaluations of auditors, along with in-depth interviews with high-level auditors.

Findings

The authors present a theoretical framework of audit tenders that identifies different formal and informal practices auditors may employ in response to evolving client expectations that arise throughout different phases of the tendering process, and elucidate relevant conditions that may enable or impede these practices.

Research limitations/implications

First, the study reveals that, in the context of auditor-client relationships, expectations cannot be considered stable, but may vary significantly throughout the tendering process. Second, the study indicates that auditors are not only determined by the formal tendering procedures, but are also influenced by their level of agency.

Practical implications

The framework has practical value by providing individual auditors guidance in managing their client relationships and, further, top management guidance for creating favorable conditions for auditors to meet client needs.

Originality/value

The findings provide a deeper and more nuanced understanding of the autonomy auditors have in responding to the contemporary pressures exerted on them.

Details

Accounting, Auditing & Accountability Journal, vol. 30 no. 8
Type: Research Article
ISSN: 0951-3574

Keywords

Article
Publication date: 26 October 2018

Greta Miezinyte, Jolita Ostrauskaite, Egidija Rainosalo, Edvinas Skliutas and Mangirdas Malinauskas

The purpose of this paper is the design and investigation of novel acrylated epoxidized soybean oil-based photocurable systems as candidate materials for optical 3D printing.

Abstract

Purpose

The purpose of this paper is the design and investigation of novel acrylated epoxidized soybean oil-based photocurable systems as candidate materials for optical 3D printing.

Design/methodology/approach

Aromatic dithiols, benzene-1,3-dithiol or benzene-1,4-dithiol, were used as cross-linking agents of acrylated epoxidized soybean oil in these systems. Kinetics of photocross-linking was investigated by real-time photorheometry using two different photoinitiators, 2, 2-dimethoxy-2-phenylacetophenone or 2-hydroxy-2-methylpropiophenone, in different quantities. The effect of the initial composition on the rate of photocross-linking, mechanical, thermal properties and swelling of obtained polymers was investigated.

Findings

The rate of photocross-linking was higher, more cross-links and shorter polymer chains between cross-linking points of the network were formed when benzene-1,4-dithiol and 2, 2-dimethoxy-2-phenylacetophenone were used in compositions. The higher yield of insoluble fraction, glass transition temperatures and values of compressive modulus were obtained when benzene-1,3-dithiol and 2, 2-dimethoxy-2-phenylacetophenone were used in compositions.

Originality/value

This is the first study of acrylated epoxidized soybean oil-based thiol-ene system by real-time photorheometry. The designed novel photocurable systems based on acrylated epoxidized soybean oil and benzenedithiols are promising renewable photoresins for rapid optical 3D printing on demand.

Details

Rapid Prototyping Journal, vol. 25 no. 2
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 1 April 1995

Susan Gilbert Beck

While one's route on the World Wide Web (WWW) may not be “straight on 'til morning,” it can be nearly as exciting. Sometimes the promise of a WWW file is not fulfilled, or…

Abstract

While one's route on the World Wide Web (WWW) may not be “straight on 'til morning,” it can be nearly as exciting. Sometimes the promise of a WWW file is not fulfilled, or different titles yield the same file, or one receives a message claiming that a server is not accessible; however, there are many good resources for the deaf that are under construction on the Web. Creative, responsible people are trying to arrange information to make it accessible for everyone. In spite of current limitations, the World Wide Web is an excellent platform on which everyone can share information and compare almost instantly the information and knowledge found.

Details

Library Hi Tech, vol. 13 no. 4
Type: Research Article
ISSN: 0737-8831

Article
Publication date: 1 January 2024

Xingxing Li, Shixi You, Zengchang Fan, Guangjun Li and Li Fu

This review provides an overview of recent advances in electrochemical sensors for analyte detection in saliva, highlighting their potential applications in diagnostics and health…

Abstract

Purpose

This review provides an overview of recent advances in electrochemical sensors for analyte detection in saliva, highlighting their potential applications in diagnostics and health care. The purpose of this paper is to summarize the current state of the field, identify challenges and limitations and discuss future prospects for the development of saliva-based electrochemical sensors.

Design/methodology/approach

The paper reviews relevant literature and research articles to examine the latest developments in electrochemical sensing technologies for saliva analysis. It explores the use of various electrode materials, including carbon nanomaterial, metal nanoparticles and conducting polymers, as well as the integration of microfluidics, lab-on-a-chip (LOC) devices and wearable/implantable technologies. The design and fabrication methodologies used in these sensors are discussed, along with sample preparation techniques and biorecognition elements for enhancing sensor performance.

Findings

Electrochemical sensors for salivary analyte detection have demonstrated excellent potential for noninvasive, rapid and cost-effective diagnostics. Recent advancements have resulted in improved sensor selectivity, stability, sensitivity and compatibility with complex saliva samples. Integration with microfluidics and LOC technologies has shown promise in enhancing sensor efficiency and accuracy. In addition, wearable and implantable sensors enable continuous, real-time monitoring of salivary analytes, opening new avenues for personalized health care and disease management.

Originality/value

This review presents an up-to-date overview of electrochemical sensors for analyte detection in saliva, offering insights into their design, fabrication and performance. It highlights the originality and value of integrating electrochemical sensing with microfluidics, wearable/implantable technologies and point-of-care testing platforms. The review also identifies challenges and limitations, such as interference from other saliva components and the need for improved stability and reproducibility. Future prospects include the development of novel microfluidic devices, advanced materials and user-friendly diagnostic devices to unlock the full potential of saliva-based electrochemical sensing in clinical practice.

Details

Sensor Review, vol. 44 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 1 February 1994

Larry Levine

Listening with spirit is the key skill which teams need to attain andsustain creative dialogue. This is especially true for organizationallearning. Building on the distinction…

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Abstract

Listening with spirit is the key skill which teams need to attain and sustain creative dialogue. This is especially true for organizational learning. Building on the distinction between dialogue and discussion, poses the question: “What makes dialogue dialogue?” and also offers tools for dialogue. The core of team dialogue is collectively listening with spirit, that is: in a group, people listen (individually) with selfless receptivity to each others′ ideas, thereby emptying themselves to create a common vessel which – shaped by and sustained by the power of the group′s collective listening – receives and contains a collective spirit. Draws on multiple disciplines including ethnography and the spiritual science of Austrian philosopher and founder of Waldorf Education, Rudolph Steiner. Provides examples of how this approach has improved the creativity of work teams. Also offers an explanation of how future search conferences work using the idea of creating a container via collective listening.

Details

Journal of Organizational Change Management, vol. 7 no. 1
Type: Research Article
ISSN: 0953-4814

Keywords

1 – 10 of 574