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This study aims to present a design and investigation of novel vanillin-based thiol-ene photocurable systems as candidate materials for optical three-dimensional printing.

Two vanillin acrylates, vanillin dimethacrylate and vanillin diacrylate, were tested in thiol-ene photocurable systems with 1,3-benzenedithiol. The kinetics of photocross-linking was investigated by real-time photorheometry using two photoinitiators, diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide or ethyl (2,4,6-trimethylbenzoyl)phenylphosphinate in different quantities. The dependencies of rheological properties of resins on the used vanillin derivative, photoinitiator, and the presence of a solvent, as well as structure, thermal and mechanical properties of the selected polymers were investigated.

The most rigid polymers were obtained from vanillin diacrylate-based resins without any solvent. The vanillin diacrylate-based polymer possessed higher values of cross-linking density, the yield of insoluble fraction, thermal stability and better mechanical properties in comparison to the vanillin dimethacrylate-based polymer.

The kinetics of photocross-linking of vanillin-based thiol-ene systems was investigated by real-time photorheometry for the first time. The designed novel photocurable systems based on vanillin acrylates and 1,3-benzenedithiol are promising renewable photoresins for optical three-dimensional printing on demand.

The purpose of this paper is to encapsulate vanilla extract by using inclusion complex of ß-cyclodextrin and also to investigate the qualities of the encapsulated powder in terms of vanillin content, moisture content, and stability under accelerated condition.

A randomized block and factorial 3×3 experimental designs with three replications were used for the studies of solvent extraction, microencapsulation of natural vanilla extract and stability of microencapsulated vanilla powder.

Ethanol concentration and ratio of vanilla to ethanol had positive effects on vanillin content. The extraction with 55 percent ethanol and the ratio of vanilla pods to ethanol as 1:4 provided the highest vanillin content of 341.23 mg/100 mL of the extract. The amount of vanilla extract and kneading time gave significant (p<0.05) effect on the microencapsulation efficiency (ME). The greatest ME found was 94.50 percent when 9 percent vanilla extract and 10 min of kneading time were used. The interaction of temperature and water activity gave significant effect on the second-order kinetic reaction of encapsulated vanilla powder (p<0.05).The most suitable condition of storage was 35°C with a_w of 0.64, providing the kinetic constant (k) of 0.0024, and correlation coefficient (R²) of 0.92 with t_half-life of 4.54 weeks.

This study provides the most suitable condition for natural vanilla extraction and microencapsulation as well as storage stability for natural vanilla powder production using the third grade vanilla pods grown at Royal Project, Khun Wang Center, Chiang Mai, Thailand.

This study aims to synthesize two different benzoxazines (Bz) monomers using bio-based and petroleum-based primary amines, respectively, and they have been compared to study their thermal and mechanical performances.

A bio-based bisphenol, Divanillin (DiVa), was formed by reacting two moles of vanillin with one mole of ethylenediamine (EDA) which was then reacted firstly with paraformaldehyde and EDA to form the benzoxazine DiVa-EDA-Bz, and secondly with paraformaldehyde and furfuryl amine (FFA) to form the benzoxazine DiVa-FFA-Bz. The molecular structure and thermal properties of the benzoxazines were characterized by fourier transform infrared spectroscopy and nuclear magnetic resonance (1H,13C) spectroscopies, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. The benzoxazines were further coated on mild steel panels to evaluate their mechanical properties and chemical resistance.

The DSC results of DiVa-FFA-Bz showed two exothermic peaks related to crosslinking compared to the one in DiVa-EDA-Bz. The DiVa-FFA-Bz also showed a higher heat of polymerization than DiVa-EDA-Bz. The TGA results showed that DiVa-FFA-Bz exhibited higher thermal stability with a residual char of 54.10% than 43.24% for DiVa-EDA-Bz. The chemical resistance test results showed that DiVa-FFA-Bz showed better chemical resistance and mechanical properties due to its higher crosslinking density.

This study shows the use of bio-based materials, vanillin and FFA, for synthesizing a benzoxazine resin and its application at high temperatures.

Mr. LEVENSTEIN, the President of the Society of Chemical Industry, in his address delivered at Liverpool recently, dealt very fully with the question of the commercial position of Great Britain as compared with other countries, more especially Germany, and emphasised the fact that if this country is to compete successfully with her contemporaries she must, to use the words of the Prince of Wales at the Gúildhall, “wake up.” After reviewing the chief factors making for Germany's advance in industry and commerce Mr. LEVENSTEIN says: “How are we to defend ourselves? Shall we rest content as we are or bestir ourselves and awake to the irresistible fact that continued apathy and indifference mean ruin to our national position?” This is strong language but not stronger than the occasion demands, for the statistics by which these observations are backed clearly indicate a marked decadence in the national prosperity notwithstanding the years of apparent “record” trade, which, however, cannot be regarded so favourably when subjected to detailed analysis and comparison. Mr. LEVENSTEIN'S suggestions to meet this situation are as follows: (1) The appointment of a competent and expert Minister of Commerce. (2) The nationalisation and extension of our canals and waterways. (3) A measure for greatly extending and improving our secondary education. (4) A sensible reform of our patent laws.

As a result of the changes caused by the preparation of foods gradually passing out of the home into the hands of manufacturers, there has arisen an absolute need for a complete supervision of the public food supplies. A supervision which shall place some limit upon the substitution of cheaper and inferior methods and dangerous materials in place of the standard formerly used in our homes.

The purpose of this review is to address the consumer’s preferences that have varied greatly in the past decade appraising the use of flavor and aroma compounds in the development of functional foods rather than consuming artificial additives. A growing interest in natural flavoring agents and preservatives have made the researchers to explore the other bio-functional properties of natural flavors beyond their ability to give a remarkable flavor to the food.

In this review, five major flavoring agents used significantly in food industries have been discussed for their bioactive profile and promising health benefits. Vanilla, coffee, cardamom, saffron and cinnamon, despite being appreciated as natural flavors, have got impressive health benefits due to functional ingredients, which are being used for the development of nutraceuticals.

Flavoring and coloring compounds of these products have shown positive results in the prevention of several diseases including carcinoma and neurological diseases such as Alzheimer’s and Parkinson’s. Such effects are attributed to the presence of phenolic compounds, which possesses free radical scavenging, anti-inflammatory antiviral and antimicrobial properties. These properties not only show a preventive mechanism against diseases but also makes the food product shelf-stable by imparting antimicrobial effects.

This paper highlights the opportunities to increase the use of such natural flavoring agents over synthetic aroma compounds to develop novel functional foods. Phenols, carotenoids and flavonoids are the major health-promoting components of these highly valued aroma ingredients.

The purpose of the study reported in this paper is to synthesis curcumin, which was reported to possess broad pharmacological effects and excellent dyeing properties, via Claisen-Schmidt condensation reaction catalysed by an efficient and green solid base catalyst, KF/Al₂O₃.

A series of catalysts with different KF loadings and varying calcination temperatures had been prepared, characterised by Brunauer–Emmett–Taller surface area, temperature-programmed desorption with CO₂ using infrared spectroscopy, X-ray powder diffraction and X-ray photoelectron spectroscopy, and tested in the Claisen–Schmidt condensation reaction. The effects of different reaction parameters such as temperature, the amount of catalyst, reactant ratio and time on the synthesis of curcumin were examined. The possibility of recycling the catalyst was also investigated in detail. Moreover, the reaction mechanism and the role of KF/Al₂O₃ in the synthetic process were discussed.

The study provides an efficient and green solid base catalyst, KF/Al₂O₃, and 64.3 per cent yield of curcumin was obtained under the optimum reaction conditions. Experimental results indicate that the third reused catalyst could retain part of the catalytic activity, and the regenerated one could be reused with reasonable catalytic activity. Besides, K₃AlF₆ was proposed as the active site of the catalyst for the reaction by the analysis of the characterization results of KF/Al₂O₃.

KF/Al₂O₃ was found to be an efficient catalyst for catalytic synthesis of curcumin and could be easily recycled several times. This information may be useful for further research and practical applications of curcumin.

This paper aims to evaluate the inhibitive effect and adsorption behavior of the 2-amino-5-thiol-1,3,4-thiadiazole vanillin (A) on copper in 3 per cent NaCl solution.

A thiazole Schiff bases were synthesized, named, 2-amino-5-thiol-1,3,4-thiadiazole vanillin (A), which was fabricated respectively on copper surface by the molecular self-assembled. Evaluation was carried out by electrochemical measurement and surface analysis techniques. Measurement of static friction coefficient scanning electron microscopy and Contact angle analysis were applied, and it is finally confirmed the existence of the adsorbed film. The inhibitive mechanism of A was evaluated by means of quantitative calculation and molecular dynamics simulation.

The electrochemical measurement indicated that the self-assembled molecular film can effectively inhibit the corrosion of copper sheet, when the concentration was 15 mmol⋅L⁻¹ and the assembly time was 6 h, the corrosion inhibition effect was the best, reaching as high as 97.5 per cent. Scanning electron microscopy results showed that the Schiff base compound forms a protective film on the surface of the copper, which effectively blocks the transfer of corrosion particles to the metal substrate, thereby inhibiting the occurrence of corrosion. Adsorption behavior of A followed the Langmuir’s adsorption isotherm and attributed to mixed-type adsorption. The results of Quantitative calculation and molecular dynamics simulation showed that A was adsorbed on Cu (111) surface in parallel.

In this study, the corrosion inhibition properties of Schiff base film were investigated by combining theory with experiment. Theoretical calculation is helpful to guide the synthesis of efficient and environmentally friendly corrosion inhibitors.

The damage caused by metal corrosion is great. The self-assembled Schiff base membrane synthesized in this paper is simple and compact, and the corrosion inhibition efficiency of copper in 3 per cent NaCl solution is 97.5 per cent.

Inhibition of metal corrosion can better save energy and reduce economic losses.

The synthesized Schiff base was prepared on the copper surface by the molecular self-assembled. The Schiff base membrane has a good corrosion inhibition effect on copper in 3 per cent NaCl solution, and the corrosion inhibition efficiency is up to 97.5 per cent.

The purpose of this paper is to test for gender-specific effects on odor-induced taste enhancement and subsequent food consumption in olfactory food marketing.

Lab experiments conducted among female and male participants using vanillin as a stimulus and ratings of sweetness, taste pleasantness and eating of sugar-free food as measures.

Odor-induced taste enhancement is gender-specific. Female consumers outperform male consumers in olfactory reaction and sweetness perception. While men outperform women in food consumption.

Odor intensity was set to the concentration level of 0.00005per cent according to the findings from (Fujimaru and Lim, 2013). The authors believe that this intensity level is appropriate for both men and women. Still, there may be some gender effects on intensity levels, which are not explored here. The author’s test for the effects of one personal factor, gender and odor-induced taste enhancement of sugar-free food. The authors think that investigating the combined effects of more personal factors such as age, culture and so on adds to the accuracy of the results.

It seems that the stronger sensory capacities of women in terms of odor detection and recognition already confirmed in the literature extends to the cross-modal effects of this sensory detection and recognition on taste enhancement. It seems appropriate to tailor olfactory food advertising according to the gender of the target audience.

Odor-induced taste enhancement is still a novel subject in marketing. While most of the research has investigated the effects of smelling congruent odors on taste perception and food consumption among mixed groups of men and women, the value of this paper lies in the investigation of the potential moderating effects of gender on this relationship.

This study aims to describe the design and synthesis of two novel azo and imine chromophores-based dyes derived from two different aldehydes with intramolecular colour matching that are pH sensitive.

The visible absorption wavelength (λ_max) was extended when azo chromophore was included in imine-based systems. The dyed patterns created sophisticated colour-changing paper packaging sensors with pH-sensitive chromophores using alum as a mediator or mordant. Due to the tight adhesive bonding, the dyes on paper’s cellulose fibres could not be removed by ordinary water even at extremely high or low pH, which was confirmed by scanning electron microscopy analysis. The dyed patterns demonstrated an evident, sensitive and fast colour-changing mechanism with varying pH, from pale yellow to red for Dye-I and from pale yellow to brown-violet for Dye-II.

The λ_max for colour changing was recorded from 400 to 490 nm for Dye-I, whereas from 400 to 520 for Dye-II. The freshness judgement of food was checked using actual experiments with cooked crab spoilage, where the cooked crab was incubated at 37 ^oC for 6 h to see the noticeable colour change from yellow to brown-violet with Dye-II. The colour-changing mechanism was studied with Fourier transform infrared (FTIR) spectra at different pH, and thin layer chromatography, nuclear magnetic resonance and FTIR spectroscopy studied the desired structure formation of the dyes. Potential uses for smart packaging sensors include quickly detecting food freshness during transportation or right before consumption.

1. Two novel azo-imine dyes have been synthesized with a pH-responsive effect. 2. The pH-responsive mechanism was studied. 3. The study was supported by computational chemistry using density functional theory. 4. The obtained dyes were used to make pH-responsive sensors for seafood packaging to judge the freshness.