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The purpose of the study reported in this paper was to prepare modified C.I. Pigment Red (PR) 170 to reduce production cost and improve application performance. The structure of the modified pigment was characterised. The colour strength, thermal stability, mobility, aqueous dispersability and ultraviolet (UV) resistance of modified pigments were studied.

Silica fume was added into the diazonium salt solution under acidic condition, followed by the activation to generate new surface. Subsequently, coupling component was dropwise added to the system to form the modified pigments evenly on the surface of silica fume in situ. The structure and properties of the modified pigment were studied by fourier transform infrared spectoscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermal gravity analysis (TG-DTA), UV-visible diffuse reflectance spectra (UV-Vis DRS), and commission internationale de L‘Eclairage (CIE L*a*b*) colour measurements.

The morphology and particle size of the modified pigment were controlled by the modification of the silica fume, and the organic pigment and silica fume formed a core–shell structure. The properties of the modified pigment including colour strength, thermal stability, mobility, aqueous dispensability and UV resistance were improved significantly.

The effect of the amount of silica fume on the thickness of the organic pigment layer and the effect of the thickness of the organic pigment layer on the properties of the modified pigment need to be studied further.

This paper shows a feasible method of the modification of the PR170 with the silica fume, and the modification can improve the properties of the PR170. The use of silica fume to modify organic pigment can realise the reuse of solid waste and reduce the production cost of the organic pigment.

This modification method of the organic pigment is adaptive and it can be adjusted to the modification of other species of the organic pigment.

The modification of the PR170 with the silica fume was carried out in its preparation process, which synchronised the preparation and modification of the organic pigment. The properties of the modified pigment were improved, which were beneficial for their application in inks and coatings.

The authors aimed to develop environmentally stable NIR‐absorbing windows by blending a near‐infrared (NIR)‐absorbing dye and a photo‐crosslinkable polymer.

To prepare an environmentally stable NIR‐absorbing window, a NIR‐absorbing dye was mixed with crosslinkable poly(vinyl cinnamate) (PVCn). The crosslinking of PVCn was carried out by photo‐dimerisation reaction of cinnamate with UV‐exposure at a wavelength of 254 nm for 4 min.

The resistance of the photo‐crosslinked hybrid films against humidity, heat, and ultraviolet radiation damage was improved dramatically relative to the pristine NIR‐absorbing dye. These improvements result from the protection of NIR‐absorbing dye to moisture exposure in the presence of the polymer network.

The simple and practical method resulted in a dramatic improvement in the environmental stability of NIR‐absorbing window.

The purpose of this paper is to describe how to synthesise polyurethane resins by using different polyester polyols and HDI isocyanurate. The polyester polyols were prepared by reacting single diol with different diacids. The effects of these polyester polyols on the performance properties of the coating films are studied.

A series of hydroxyl‐terminated polyester polyols were synthesised by using 1,4‐cyclohexanedimethanol (1,4‐CHDM) with different diacids such as 1,3‐cyclohexanedicarboxylic acid (1,3‐CHDA), 1,4‐CHDA, adipic acid (AA), azelaic acid (AZA), and isophthalic acid (IPA). The general properties including acid number, hydroxyl number average molecular weight, polydispersity index, and viscosity of these polyester polyols were evaluated. Different coating formulations were developed by using polyester polyols and HDI isocyanurate. These coatings were applied on sand blasted mild steel panels and glass panels and were cured in hot air oven. Various mechanical, thermal and chemical resistance properties of the coating films were evaluated.

The paper shows that, the polyurethane coatings have good resistance to water and other chemicals and can be used safely in exterior applications. In polyester polyols for polyurethane coating, CHDA showed a good balance in mechanical properties, which may be attributed to its unique cycloaliphatic structure and 1,4‐substitution. The polyester polyol based on aromatic diacids provided polyurethane coatings with maximum hardness and high T_g.

The polyurethane resins were prepared from polyester polyol (made up of cyclohexanedimethanol (CHDM) and CHDA, IPA, AA, and AZA). Besides, this, it can be synthesised from some other polyester polyols (having different acids and alcohols) or polyether polyols. In addition to this, some other isocyanates such as TDI, MDI, HMDI, etc. can also be used.

The paper has provided a better solution for developing high solid polyurethane coatings for exterior applications due to presence of cycloaliphatic compounds.

In this paper, cyclohexyl dibasic acids have been used as the replacement for the aromatic dibasic acids. In aromatic dibasic acids, the phenyl ring readily absorbs UV‐light limiting the photo‐oxidative stability of the polyesters. So, these studies will help to develop high‐solid polyurethane coatings which could find numerous industrial applications in surface coatings.

Use of highly dye doped nano composite for organic pollutant degradation.

One-pot synthesis of titanium nano-particles were carried out in the presence of N719 dye.

High dye doping and exceptional dye degradation efficiency was observed. Within 25 min, 99 per cent of methylene blue was removed from waste water.

A novel one-pot synthesis of the composite was introduced.

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.

The study aims to find potential method to enhance the stability and antioxidant activity of vitamins.

Vitamin E (VE) and β-cyclodextrin (CD) were used to prepare the VE-β-CD inclusion complex via a solution method. The yielded VE-β-CD obtained from optimal experimental conditions was characterized. The mechanism of complex formation and the properties of the complex was investigated by steady-state and time-resolved fluorescence techniques. The antioxidant activity of VE-β-CD was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and compared with pure VE.

Three experimental factors – reaction temperature (T), molar ratio of VE to β-CD (rm) and inclusion time (t) – were studied for the preparation of VE-β-CD. At experimental conditions of T = 60°C, rm = 1:3 and t = 3 h, a maximum inclusion rate of VE (78.62%) was obtained. The Fourier-transform infrared spectroscopy (FTIR) shows that VE molecule was physically encapsulated by β-CD in the yielded product. Subsequentially, the steady-state fluorescence intensity of VE was found to increase upon encapsulation by β-CD due to the hindrance of fluorescence quenching of VE molecules inside the hydrophobic cavity of β-CD, and an inclusion constant K was determined to equal 3.58 × 103 L/mol from the fluorescence results. The fluorescent observation was confirmed by time-resolved fluorescence experiment as the lifetime of VE increased with an increase in β-CD concentration.

The ability of removing radicals by VE was significantly enhanced after the formation of inclusion complex with β-CD.

The purpose of this paper is to test absorption characteristics of some newly synthesised 4‐hidroxycoumarins, containing phenyl‐prop‐2‐enoyl group at the 3‐position. Change in spectral characteristics in solvents of different polarity (chloroform and acetonitrile) was followed in regard to the influence of the substitution at the phenyl ring and influence of concentration H⁺ ions. Effectiveness of tested substances was compared with well‐known UV absorbers such as benzophenone‐3 and butyl methoxydibenzoylmethane (BMDM).

All the tested substances were dissolved in chloroform and acetonitrile, with 10‐3 mmol concentration range. The pH was adjusted using 0.1 mol/l HCl, glacial acetic acid, 0.1 mol/l NaOH (aqueous solution) and 0.1 mol/l NaOH (methanolic solution). Spectrophotometric measurement was recorded in the range of 200‐800 nm, using 1‐cm quartz cells.

The tested 4‐hydroxycoumarin derivatives showed good UV absorption properties in the range 280‐380 nm. Substitution on the phenyl ring changes the shape of the absorption maxima. The changes depend on the properties of the substituent as well as the acidity of the solution.

Introducing an electron‐donating substituent on the phenyl‐prop‐2‐enoyl group can shift absorption maximums to longer wavelength. In addition, the variation in substituents on the synthesised substances and pH of the solution could also be studied.

The new compounds showed good UV absorption, making them potential candidates for many applications. The practical importance of the tested substances are derived from their stability, relatively easy synthesis and good UV absorption properties.

The paper shows that the tested coumarins derivatives were new compounds with good UV absorption properties, making them good UV absorbers of commercial potential. The tested coumarins showed good UV absorption properties in the range 280‐380 nm, making them potential candidates for many applications.

This paper aims to provide a flexible polyurethane (PU) film with visible light trapping ability, photothermal conversion and energy storage performance by covalently bonded a visible light absorbing dye into the polymer through copolymerization.

For this target solution copolymerization of diphenyl-methane-diisocyanate (MDI), poly(1,4-butylene adipate) (PBA2000), polyethylene glycol (PEG) of different molecular weight, self-made dye, 1,4-butanediol (BuOH) was carried out in a flame-dried flask under an inert nitrogen (N₂) atmosphere. First, an isocyanate-terminated prepolymer of dried PEG, MDI and PBA2000 was prepared in dimethylformamide and stirred for 1 h at 35°C. Then, self-made dye and 1, 4-butanediol (BuOH) were added and heated at 85°C for 3 h to get photothermal conversion polyurethane (PTPU) solution. Allowed the solution to dry at room temperature for seven days and then at 65°C for 12 h to get PTPU films.

The flexible PU films with photothermal conversion and energy storage performances were successfully synthesized and the functional films presented both excellent energy storage and mechanical property when the molecular weight of PEG was in the range of 6,000∼10,000.

The materials that were used in this research paper had a reasonably low cost. Also, the procedures for the synthesis of dye and polymers were extremely easy because there was no need for high pressure or temperature and no dangerous solvents were used.

The photothermal conversion property and mechanical performance of the synthesized flexible PU films were characterized. The results have proved that these films were soft and elastic, and have certain photothermal conversion and energy storage ability, thus can be used in the surface finishing of special fabric and leather.

Visible light trapping photothermal conversion PU flexible film with energy storage capability was prepared for the first time.

At first, the organic/inorganic and hybrid PV materials by their electrical model are described. Then the proposed converter topology, circuit analysis and various operating modes of converter according to on/off timing of switches are investigated. The current and voltage in the converter components are illustrated and the voltage gain and switching stress of proposed converter are presented. Finally, to show the effectiveness of the proposed converter, the power loss analysis is provided and the simulation is done in PSIM software. In the last section, the advantages of the proposed topology of higher efficiency by lower number of components in compare with other conventional topologies are presented.

In this paper, an improved topology of DC-DC converter based on VL technique is proposed for Perovskite Solar cells (PeSCs). The PeSCs attracted a lot of interest due to their potential in combining the advantages of both organic and inorganic components. The proposed converter by using fewer components and higher output voltage generation in compare with conventional ones could be a good candidate for PeSCs due to lower efficiency of this cells. The performance of converter is expressed in continuous conduction mode (CCM) and discontinuous conduction mode (DCM), and the boundary conditions for the proposed converter is presented.

By using VL technique, this converter is used to boost the lower output voltage levels of PeSCs for grid connection. The PV cell output voltage is increased from 24.5 V to 106 V by proposed converter topology. The step-by-step voltage increasing by charging and discharging of inductor and capacitor is used for boosting the input voltage. By comparing other converters, there is no design complexity in the proposed converter structure, and the power loss is much reduced which increases the converter efficiency. On the other hand, due to using lower number of elements of energy storage elements such as inductors and capacitors, the converter cost is also diminished. Therefore, the design topology simplicity which result simple control algorithm and lower number of components which diminish the system cost by appropriate voltage boosting capability are the main advantages of this proposed topology for new PeSCs which don’t have enough efficiency in compare with old Si PV cells.

In this paper, by using the lower number of components a new structure of DC-DC converter based on the VL technique is proposed. The advantages of this converter such as the simplicity, easier control and high voltage gain by lower power loss, could make this converter a good candidate for new PeSCs where the system whole efficiency will be a critical point to have the unique properties of this new materials in lower loss.

Now formed for almost two years, the Brazilian Printed Circuit Association, ABRACI (Associação Brasileira de Circuitos Impressos), held on 17–18 September 1987 at Curitiba its first seminar on printed circuit technology. The association, with 150 members, is going from strength to strength and the 1987 Seminar was attended by 250 persons from several states. Participants included representatives from well known international companies (Du Pont, Degussa, IBM, Unisys, etc.), Government, Universities and local companies. The programme of 16 papers was divided into four sessions: Market, Quality, Manufacturing and SMT. The two‐day event proved too short for the enthusiasm of participants.