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The purpose of this paper is to study the effective procedure for blocking and deblocking isocyanate by sodium bisulphite with special cosolvent and dropwise method.

A number of analytical techniques, including Fourier transform infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC) and Thermo gravimetric analyser (TGA) were employed to assess the reactions between isocyanates and sodium bisulphite, water, cosolvent, also the deblocking temperature of blocked isocyanates.

The blocked isocyanates reacted with sodium bisulphite, water and cosolvent via a special procedure. It was found that the − NCO functional groups of the isocyanates were completely blocked by sodium bisulphite and a new method for determining the lowest deblocking temperature of the blocked isocyanates was described. It was revealed that the deblocking temperature of blocked isocyanates by sodium bisulphite was lower than others.

The paper provides some useful information about the blocking and deblocking of isocyanate, which would be helpful for the preparation of blocking and deblocking isocyanate, and guiding the practical applications of blocked isocyanate.

The investigation found that the sodium bisulphite was a very efficient blocking agent for isocyanates at the room temperature via the special procedure developed. On the basis of emulsion polymerisation theory, polymer isocyanates were blocked by sodium bisulphite, which realised the new breakthrough effectively by means of controlled temperature, stirring speed and optimum dropwise speed in the whole reaction system. Meanwhile, the special cosolvent could improve the intermiscibility of isocyanate in sodium bisulphite aqueous solution, reduce the side reaction of isocyanate with water and accelerate reaction rate of isocyanate with sodium bisulphite. If no cosolvent was present, the blocked system would not be homogeneous.

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.

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.

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.

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.

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

This paper aims to evaluate the efficiency and mechanism of three kinds of expired nitroimidazole antibiotics as corrosion inhibitor for mild steel in 1M HCl.

Evaluation was carried out by weight loss and electrochemical techniques. The surface morphology and the composition of the elements of adsorption layer are studied by scanning electron microscopy and energy dispersive spectrometer.

The experimental results reveal that the maximum value of inhibition efficiency appear at an extreme point of concentration with the increase of concentration of the inhibitors. Ornidazole has better corrosion inhibition than metronidazole but not as tinidazole. The inhibitors all act as cathodic type corrosion inhibitor. The adsorption of ornidazole, metronidazole and tinidazole on mild steel obeys Langmuir adsorption isotherm and belongs to chemisorption of electron donating. Combined with the molecular structure of the corrosion inhibitor and the experimental structure, the authors propose a detailed mechanism analysis.

The expired nitroimidazole antibiotics as corrosion inhibitor for mild steel in hydrochloric acid solution is first studied. It provides a way to deal with expired drugs, thereby reducing environmental pollution. The study explored the inhibition mechanism affecting by comparison different structure of three kinds of expired nitroimidazole antibiotics molecular, providing theoretical support for the preparation of the new inhibitor.

This paper aims to present an image-based visual servoing algorithm for a multiple pin-in-hole assembly. This paper also aims to avoid the matching and tracking of image features and the remaining robust against image defects.

The authors derive a novel model in the set space and design three image errors to control the 3 degrees of freedom (DOF) of a single-lug workpiece in the alignment task. Analytic computations of the interaction matrix that link the time variations of the image errors to the single-lug workpiece motions are performed. The authors introduce two approximate hypotheses so that the interaction matrix has a decoupled form, and an auto-adaptive algorithm is designed to estimate the interaction matrix.

Image-based visual servoing in the set space avoids the matching and tracking of image features, and these methods are not sensitive to image effects. The control law using the auto-adaptive algorithm is more efficient than that using a static interaction matrix. Simulations and real-world experiments are performed to demonstrate the effectiveness of the proposed algorithm.

This paper proposes a new visual servoing method to achieve pin-in-hole assembly tasks. The main advantage of this new approach is that it does not require tracking or matching of the image features, and its supplementary advantage is that it is not sensitive to image defects.

In view of the defects of glued wood beams, a new composite member – reconstituted bamboo board reinforced glued wood beams is proposed to improve the bearing capacity of glued wood beams.

The bending test studied the ordinary glulam beams and the reinforced glulam beams with different layer numbers and different layer thicknesses by comparing with six kinds of glulam beams strengthened with bamboo scrimber and one kind of ordinary glulam beams and used the method of third-point stepwise loading on the glulam beams strengthened with bamboo scrimber.

The bamboo scrimber improved the bending behavior of the ordinary glulam beams. The 10 mm bamboo scrimber layer can meet the requirements of the maximum ultimate bending capacity and minimize the defects. So 10 mm bamboo scrimber layer was the optimal thickness. During the loading process, the strain change of the normal section of the reconstituted bamboo board reinforced glued wood beam basically conforms to the plane section assumption.

The bending rigidities of the glulam beams strengthened with bamboo scrimber increased up to 28.25%, 8.53% and 76.67%, and the ultimate bending capacity increased from 83.44% to 99.34% with the increase of the bamboo scrimber plate layers (the replacement rate). The ultimate bending capacities and the bending rigidities of the glulam beams strengthened with bamboo scrimber increased to 52.32%∼60.18% and 90.07%∼99.34% with the changing of the bamboo scrimber thicknesses from 7.1 mm to 25 mm.

This paper aims to analyze the relationships between human resource supply chain management (HRSCM), corporate culture (CC) and the code of business ethics (CBE) in the MENA region.

In this study, the author adopted a quantitative approach through an online Google Form survey for the data-gathering process. All questionnaires were distributed to the manufacturing and service firms that are listed in the Chambers of the Industries of Jordan, Saudi Arabia, Morocco and Egypt in the MENA region using a simple random sampling method. About 567 usable and valid responses were retrieved out of 2,077 for analysis, representing a 27.3% response rate. The sample unit for analysis included all middle- and senior-level managers and employees within manufacturing and service firms. The conceptual model was tested using a hypothesis-testing deductive approach. The findings are based on covariance-based analysis and structural equation modeling (SEM) using PLS-SEM software. The author performed convergent validity and discriminant validity tests, and bootstrapping was also applied.

The empirical results display a significant and positive association between HRSCM and the CBE. The CC and the CBE tend to be positively and significantly related. Therefore, HRSCM can play a key role in boosting and applying the CBE in firms. For achieving the firm purposes, more attention to the HR personnel should be paid to implement the CBE. The high importance of the CBE becomes necessary for both the department and the firm.

Such results can provide insightful information for HR personnel, managers and leaders to encourage them to develop and maintain an effective corporate code of conduct within their organizations.

This paper tries to explore the linkages between HRSCM, CC and CBE in the Middle East region due to the lack of research available that analyzes the relationship between them. Not only that, but it also offers great implications for Middle Eastern businesses.

The purpose of this paper is to study the functionality of additively manufactured (AM) parts, mainly depending on their dimensional accuracy and surface finish. However, the products manufactured using AM usually suffer from defects like roughness or uneven surfaces. This paper discusses the various surface quality improvement techniques, including how to reduce surface defects, surface roughness and dimensional accuracy of AM parts.

There are many different types of popular AM methods. Unfortunately, these AM methods are susceptible to different kinds of surface defects in the product. As a result, pre- and postprocessing efforts and control of various AM process parameters are needed to improve the surface quality and reduce surface roughness.

In this paper, the various surface quality improvement methods are categorized based on the type of materials, working principles of AM and types of finishing processes. They have been divided into chemical, thermal, mechanical and hybrid-based categories.

The review has evaluated the possibility of various surface finishing methods for enhancing the surface quality of AM parts. It has also discussed the research perspective of these methods for surface finishing of AM parts at micro- to nanolevel surface roughness and better dimensional accuracy.

This paper represents a comprehensive review of surface quality improvement methods for both metals and polymer-based AM parts.

In recent years, China has shifted its competitive strategy from competing on low cost to producing higher value added products and services, and the country has made the promotion of business excellence a national strategic priority. As a consequence, Chinese organizations need to know the factors that will make them world-class companies. Until recently, not much research has been done into these factors in the Chinese context. The few studies available unfortunately were mainly done only into specific elements of excellence and specific improvement techniques; a holistic and scientifically validated framework for creating high performance organizations (HPOs) cannot be found. The purpose of this study is to evaluate such a framework, which was quite recently developed, for the Chinese context.

A possible way forward is to use the HPO framework which was validated in earlier studies for the Asian context. In this paper, this research question is answered: Can the HPO framework be used to help Chinese organization to evaluate and improve the factors for excellence in the Chinese context? The study used a questionnaire which was distributed to respondents of a Chinese state-owned manufacturing enterprise. The results were discussed during a workshop to arrive at the main attention points for the organization.

The HPO framework was validated for the Chinese context and yielded valuable recommendations for improvement for the case company.

This study fills the gap which currently exists in empirical research about organization performance practices in Chinese. The study also has practical implications as management of Chinese state-owned enterprises, and possibly other Chinese companies, are now able to undertake focused improvement actions.

The purpose of this paper is to perform a systematic review on the application of different multi-criteria decision-making (MCDM) methods in solving the site selection problem across multiple problem domains. The domains are energy generation, logistics, public services and retail facilities. This study aims to answer the following research questions: Which evaluating criteria were used for each site selection problem domain? Which MCDM methods were frequently applied in a particular site selection problem domain?

The goals of the systematic review were to identify the evaluating criteria as well as the MCDM method used for each problem domain. A total of 81 recent papers (2014–2018) including 32 papers published in conference proceedings and 49 journal articles from various databases including IEEE Xplore, PubMed, Springer, Taylor and Francis as well as ScienceDirect were evaluated.

This study has shown that site selection for energy generation facilities is the most active site selection problem domain, and that the analytic hierarchy process (AHP) method is the most commonly used MCDM method for site selection. For energy generation, the criteria which were most used were geographical elements, land use, cost and environmental impact. For logistics, frequently used criteria were geographical elements and distance, while for public services population density, supply and demand, geographical layout and cost were the criteria most used. Criteria useful for retail facilities were the size (space) of the store, demographics of the site, the site characteristics and rental of the site (cost).

This study is limited to reviewing papers which were published in the years 2014–2018 only, and only covers the domains of energy generation, logistics, public services and retail facilities.

MCDM is a viable tool to be used for solving the site selection problem across the domains of energy generation, logistics, public services and retail facilities. The usage of MCDM continues to be relevant as a complement to machine learning, even as data originating from embedded IoT devices in built environments becomes increasingly Big Data like.

Previous systematic review studies for MDCM and built environments have either focused on studying the MCDM techniques itself, or have focused on the application of MCDM for site selection in a single problem domain. In this study, a critical review of MCDM techniques used for site selection as well as the critical criteria used during the MCDM process of site selection was performed on four different built environment domains.