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The purpose of this paper is to study and minimize loss of vitamin B₉ in bread during warming protocol.

In this study, warming intensity, warming time, warming device, and bread storage method were selected as the most effective factors on B₉ loss in bread. The variation of B₉ in bread and its loss were studied with orthogonal array design (OAD) using the L₉ optimization matrix.

With a calculated per cent of contribution (P%) of error of 0.38 per cent and according to the analysis of variance, ANOVA, of the fluorescence data, 86 per cent of B₉ was saved by using toaster as the warming device, a bread warming temperature of <200^○F and a warming time of <10min. Fluorescence method evaluated warming intensity and warming device as the most powerful factors affecting the B₉ concentration in bread with corresponding P% of 42.28 per cent and 41.72 per cent, respectively.

In conclusion, heat destroyed significant portion of B₉ in bread during daily warming protocols, and the suggested optimized parameters obtained in this work significantly minimized this loss.

The OAD can be used to effectively evaluate effective parameters on food science investigations.

The purpose of this paper is a new thin-film based sensor proposed for sensitive and selective detection of mercury (Hg²⁺) ions in water. The thin-film platform is easy to use and quick for heavy metal ions (HMIs) detection in the picomolar range. Ion-selective self-assembled monolayer's (SAM) of thiol used for the detection of HMIs above the Au/Ti top surface.

A thin-film based platform is suitable for the on-field experiments and testing of water samples. HMIs (antigen) and thiol-based SAM (antibody) interaction results change in surface morphology and topography. In this study, the authors have used different characterization techniques to check the selectivity of the proposed method. This change in the morphology and topography of thin-film sensor checked with Fourier-transform infrared spectroscopy, surface-enhanced Raman scattering spectroscopy, atomic force microscopy and scanning electron microscopy with energy dispersive x-ray analysis used for high-resolution images.

This thin-film based platform is straightforward to use and suitable for real-time detection of HMIs at the picomolar range. This thin-film based sensor platform capable of achieving a lower limit of detection (LOD) 27.42 ng/mL (136.56 pM) using SAM of Homocysteine-Pyridinedicarboxylic acid to detect Hg²⁺ ions.

A thin-film based technology is perfect for real-time testing and removal of HMIs, but the LOD is higher as compared to microcantilever-based devices.

The excessive use and commercialization of nanoparticle (NPs) are quickly expanding their toxic impact on health and the environment. The proposed method used the combination of thin-film and NPs, to overcome the limitation of NPs-based technique and have picomolar (136.56 pM) range of HMIs detection. The proposed thin-film-based sensor shows excellent repeatability and the method is highly reliable for toxic Hg²⁺ ions detection. The main advantage of the proposed thin-film sensor is its ability to selectively remove the Hg²⁺ ions from water samples just like a filter and a sensor for detection at picomolar range makes this method best among the other current-state of the art techniques.

This paper aims to focus on the most popular technique nowadays, the use of microwave irradiation in organic synthesis; in a few years, most chemists will use microwave energy to heat chemical reactions on a laboratory scale. Also, many scientists use microwave technology in the industry. They have turned to microwave synthesis as a frontline methodology for their projects. Microwave and microwave-assisted organic synthesis (MAOS) has emerged as a new “lead” in organic synthesis.

Using microwave radiation for synthesis and design of fluorescent dyes is of great interest, as it decreases the time required for synthesis and the synthesized dyes can be applied to industrial scale.

The technique offers many advantages, as it is simple, clean, fast, efficient and economical for the synthesis of a large number of organic compounds. These advantages encourage many chemists to switch from the traditional heating method to microwave-assisted chemistry.

This review highlights applications of microwave chemistry in organic synthesis for fluorescent dyes. Fluorescents are a fairly new and very heavily used class of organics. These materials have many applications, as a penetrant liquid for crack detection, synthetic resins, plastics, printing inks, non-destructive testing and sports ball dyeing.

The aim value of this review is to define the scope and limitation of microwave synthesis procedures for the synthesis of novel fluorescent dyes via a simple and economic way.

The purpose of this research is as follows: DPP-BOH-PVA has been synthesized from 1,1′:3′,1″-terphenyl-5'-boronic acid (DPP-OH) and polyvinyl alcohol (PVA). The afterglow lifetime of DPP-BOH-PVA was studied by changing contents of DPP-OH (1, 2 and 4 Wt.%). These films were characterized with Fourier transform infrared, X-ray diffraction as structural analysis and DSC as thermal analysis. Afterglow lifetimes were evaluated as time-resolved emission decay profile analysis. Fiber films of DPP-BOH-PVA-2-E have been prepared by electrospinning method with the diameter of 5 μm and afterglow life time of 2.1 s (@ 535 nm) under ambient conditions. Stimulus responsive properties with afterglow emission for fiber film were investigated.

During the synthesis of the polymer, modification was carried out using DPP-OH/PVA with a molar ratio of 1/4, under an alkalinity medium with ammonium hydroxide and with a temperature of 80°C.

XRD results indicate that DPP-BOH-PVA film had high crystallinity, which is crucial for preparing organic room temperature phosphorescence (RTP) materials.

The reaction mixture must be stirred continuously. Temperature should be controlled to prevent the rapid evaporation of ammonium hydroxide.

This study provides technical information for the synthesis of multidimensional stimulation response RTP micron fiber thin film. The electrospinning technology may also promote the applications of the large areas of RTP films.

This resin will be used for the multidimensional stimulation response RTP fiber thin film.

The diameter of fiber film of PP-BOH-PVA-2-E by electrospinning method was in the range of 5 μm, and its afterglow lifetime decayed to be 2.1 s.

Parallel factor analysis (PARAFAC) coupled with support-vector machine (SVM) was carried out to identify and discriminate between the fluorescence spectroscopies of coconut water brands.

PARAFAC was applied to reduce three-dimensional data of excitation emission matrix (EEM) to two-dimensional data. SVM was applied to discriminate between six commercial coconut water brands in this study. The three largest variation data from fluorescence spectroscopy were extracted using the PARAFAC method as the input data of SVM classifiers.

The discrimination results of the six commercial coconut water brands were achieved by three SVM methods (Ga-SVM, PSO-SVM and Grid-SVM). The best classification accuracies were 100.00%, 96.43% and 94.64% for the training set, test set and CV accuracy.

The above results indicate that fluorescence spectroscopy combined with PARAFAC and SVM methods proved to be a simple and rapid detection method for coconut water and perhaps other beverages.

The use of databases and microcomputers enables almost anyone to analyse a scientific field. Forecasting scientific production is a way of estimating trends in various countries, patents, thresholds of investment, etc. This analysis of trends can be used to determine research policy. Fundamental research and R&D must obviously be developed with full regard to results present in the international scientific literature. Moreover, it is important to view the various human and financial potentials involved in certain areas. The aim of this paper is to show how, with an information tool such as the Chemical Abstracts database, it is possible to carry out various analyses of scientific subjects. The authors present a real‐life case study developed at the laboratory of the Centre de Recherche Retrospective de Marseille; the work was closely related to the analytical work on various liquefaction products from the French coal liquefaction pilot plant. The database used was Chemical Abstracts. Two periods corresponding to two files have been considered: CA 77 (from 1977 to 1981) and CA 82 (from 1982 to date). The software used allows most types of search, and the mathematical analysis and trends were determined with an Apple II/e computer using the programs Vitrend, Visiplot and Appleplot.

The various electronic component parts and materials that are used in the construction of spacecraft electronic boxes have been chemically analysed. An elemental distribution is recorded for items that include paint, aluminium alloy structure, printed circuit boards and their soldered joints, attachment screws and ten different conventional leaded components. This data may be of use to future projects and to those involved in recycling electronic hardware.

This paper proposes to examine a simple and cost‐effective method of integrating a reflector surface with a silicon‐based microfluidic channel for enhanced biosensing through the method of fluorescence in a microfluidics and nanofluidics‐based lab‐on‐a‐chip device.

Herein, the reflector is integrated with silicon‐based microfluidic channels and fluorescence measurements were carried out using alexafluor 647 particles. Two types of microfluidic channel surfaces were used, with and without reflector integration, for the experiments.

The experimental results prove that the proposed technique of partial reflector integration within microfluidic or nanofluidic channel surfaces is highly suitable for fluorescence‐based detection of single molecules and low concentration fluorophore‐tagged receptors.

It is believed that this is a novel work of integrating a reflector with a microfluidic channel surface for fluorescence‐based biodetection. This method will be very useful for fluorescence‐based biosensors in detecting low concentration fluorophores and single molecules.

The purpose of this study aims to synthesize a novel donor–acceptor dye based on phenothiazine as a donor (D) and nonconjugated spacer was devised and synthesized by condensing of 2,2'-(1H-indene-1,3(2H)-diylidene) dimalononitrile with aldehyde and the practical synthesis methodology as given in Scheme 1.

The prepared phenothiazine dye was systematically experimentally and theoretically examined and characterized using nuclear magnetic resonance spectroscopy (1H,13C NMR), Fourier-transform infrared spectroscopy (IR) and high-resolution mass spectrometry. Density functional theory (DFT) and time-dependent density functional theory DT-DFT calculations were implemented to determine the electronic properties of the new dye

The UV-Vis absorption and fluorescence spectroscopy of the synthesized dye was investigated in a variety of solvents with varying polarities to demonstrate positive solvatochromism correlated with intramolecular charge transfer (ICT). The probe’s quantum yields (Фf) are experimentally measured in ethanol, and the Stokes shifts are found to be in the 4846–9430 cm⁻¹ range.

The findings depicted that the novel (D-π-A) chromophores may act as a significant factor in the organic optoelectronics.

The purpose of this paper is to enhance the limited fluorescence of mica titania (MT) effect pigments by coating them with peripherally substituted zinc phthalocyanines (ZnPc).

The effects of deposition medium, temperature, time, initial organic pigment/MT ratio on deposition behaviour and efficiencies were investigated separately for ZnPc, nitro (TNZnPc) and amino (TAZnPc) substituted ZnPc’s.

TNZnPc could be deposited in the form of well-defined crystals on MT with per cent 64 ± 5 efficiency in chloroform at 50°C within 5 h and the amount deposited was linearly dependent on the initial TNZnPc concentration. TNZnPc fluorescence emissions, which appear mainly at 460 and 685 nm in pure pigments, could be observed in combination with MT (MT-TNZnPc) as well. A spectral analysis on the non-overlapping region of the spectrum with two different excitations (385 and 630 nm) revealed that, respectively, up to threefold to sixfold increase is possible to attain, depending on the excitation wavelengths.

Efficiency of deposition could not be taken above per cent 11 ± 4 with TAZnPc. Although ZnPc could be deposited with per cent 57 ± 3 efficiency, the pigment was not effective in imposing its fluorescence characteristics over MT.

Combining inorganic effect pigments with organic dye molecules is an idea that has been elaborated mainly for producing different colour effects and stabilization of dye molecules against agglomeration. Here, for the first time, it is used to enhance the fluorescence of the effect pigments.