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The purpose of this paper is to elucidate the influences of the animal fat and fatty acid type on the formation of polycyclic aromatic hydrocarbons (PAHs) and to propose a formation mechanism of PAHs in fat during electric roasting, which is a method of non-direct-contact-flame heating.

The effects of animal fats and model fat on the formation of PAHs were valued on the basis of the ultra high-performance liquid chromatography data. The corresponding products of the FAME pyrolysis were detected by TG-FTIR. The proposal formation mechanism of PAHs was based on the summary of the literature.

Contrary to the International Agency for Research on Cancer, DF had higher risk with 280.53 ng/g of concentration after being roasted than the others animal fats of red meat in terms of PAHs formation. This research also ensured the importance of fat on PAHs formation, the concentration of PAHs in pure fats was higher after being electric roasted than that in meat patties and juice which made from corresponding animal fat. What is more, during pure animal fats and meat products being processed, less PAHs formed in the fat with lower extent of unsaturation and lower content of linolenate. In the same way, methyl linolenate demonstrated the significant increasement to PAHs formation compared to the other fatty acids. And, the number of carbon atom and the extent of unsaturation in fatty acid affects the formation of PAHs during roasting. The detection of alkene and alkane allows to propose a formation mechanism of PAHs during model fat being heated. Further study is required to elucidate the confirm moleculars during the formation of PAHs.

This work studied the effect of the carbon atom number and the unsaturation extent of fats and model fats on the formation of PAHs. This work also assure the important of alkene and alkane on the pyrolysis of model fats. This study also researched the formation and distribution of PAHs in pure fats and meat products after being heated.

The purpose of this paper is to evaluate the properties of several thiol-acrylate photosensitive systems and compare with corresponding acrylate free-radical systems. The potential stereolithography applications of thiol–ene photosensitive systems are also discussed.

In the both thiol–ene and acrylate free-radical photosensitive systems, various key performances were characterized. The function group conversions were characterized by real-time Fourier transform infrared spectroscopy. The tension strength was determined according to the standard ASTM D638-2003, the flexible strength was determined according to ASTM D790-07 and the hardness was measured according to ASTM D2240-05. The volume shrinkage was measured by dilatometer method. The glass transition temperature was analyzed by differential scanning calorimeter.

As adding mercapto propionates into acrylate system, the inhibition of polymerization by oxygen was controlled and the flexible performance was improved. In addition, the photosensitive resin showed better tension strength, higher elongation at break and lower volume shrinkage. Among the four mercapto propionates, rigid TEMPIC showed most obvious affect, followed hexa-functional DPMP, tetra-functional PETMP and tri-functional TMMP.

Although the thiol–ene photosensitive resin has unmatched advantages in performance, there are no reports on the thiol–ene photosensitive resin in the stereolithography application. In this study, thiol–ene photopolymerization material was first tentatively implemented in stereolithography area. Several critical performance parameters were compared between thiol–ene and acrylate free-radical photosensitive systems.

The commercial success of electro‐deposition of aqueous coating is mainly concerned with the development of water‐soluble film forming polymers. The field of these water‐soluble polymer systems for surface coating application is growing rapidly and expanding vigorously and they are destined to play a leading role in the near future. This may be mainly attributed to regulations on emissions, environment and ecology. In doing so, the electrodeposition technique offers a remarkable assistance to these systems at comparatively low cost, low energy requirement and high utilization efficiency. Research workers have done work on water‐soluble alkyds, epoxies and acrylics.

Because domestic heating appliances have the advantage of reducing emissions of greenhouse gas, their use is greatly increased and is largely recommended by European governments. However, some recent studies revealed that residential wood stoves and inserts are the source of many chemicals in the form of gases (CO₂, CO, SO₂, NO_x), volatile organic compounds (alkane, alkenes, benzene, etc. …) and tars (mainly constituting poly‐aromatic hydrocarbons). The most important of them in terms of the emission factor and impact on environment and human health are carbon monoxide and fine particles. The aim of this study is to test the activity of a Pd‐based catalyst on the reduction of gas and particles during wood combustion in a domestic fireplace.

A catalytic system, placed at the exit of the fireplace, was developed to reduce pollutants. Pollutant characterization of a domestic fireplace from FONDIS SA, according to two paces of functioning (nominal and low‐charge), was performed with and without the presence of the catalyst. Fine and ultrafine particle distributions were characterized using an Electrical Low Pressure Impactor.

The presence of a catalyst drastically decreases the emission factors of CO. Though performing efficiently with respect to the total suspended particles emission factor, it does not significantly affect the emission factors of aerosols. Nevertheless, in the presence of the catalyst, air supply conditions slightly modify size distributions of PM0.1 to PM10.

A purification assembly, having catalysts for gases and combustion fumes from solid fuel heating apparatus, was patented and fireplaces are now commercially available from FONDIS SA.

This work was an adaptation of the catalytic system present in the automotive Diesel exhaust engines. It was not necessary to consult previous laboratory experiments in order to perform its activity because it was directly tested at the duct fireplace.

This paper aims to investigate the feasibility of potassium permanganate (KMnO₄) as an efficient discharging agent for indigo-dyed denim fabrics and identification of key variables for its cost-efficient implication.

Response surface methodology, which is a statistical technique for the optimization of process variables, was used to study the effect of three key variables, i.e. KMnO₄ concentration, printing paste pH and reaction time on whiteness and strength of discharged printed fabric. Regression models were developed to predict response variables, i.e whiteness, tensile strength and tear strength of discharge printed denim.

It was found that some captivating discharge printing effects could be produced using appropriate KMnO₄ concentration, printing paste pH and reaction time without any significant loss in the fabric strength.

This study highlights the practical implication of KMnO₄ to be used as a safe and effective discharging agent under different conditions and to optimize the parameters using statistical analysis to ensure minimum loss in textile properties. The use of denim has evolved over the decades from a rough and tough workwear to highly fashionable apparel. Various dry and wet processing techniques have been introduced in recent years for the value-addition of denim – discharge printing is one of them. As lab to bulk reproducibility requires some sort of experience and adjustments in main parameters, the practical feasibility on the bulk scale should be adjusted in advance by means of the lab scale experimentation.

The KMnO₄ oxidation process is considered eco-friendly because manganese dioxide, which is formed when permanganate is reduced, can be recycled. Thus, the use of KMnO₄ can be considered as an eco-friendly safe process for the discharging of indigo dyes.

The purpose of this study is to explore the feasibility of utilizing agricultural (almond shell, rice husk and wood) waste biochars for partial cement replacement by evaluating the relationships between the physiochemical properties of biochars and the early-age characteristics of cement pastes.

Biochars are prepared through the thermal decomposition of biomass in an inert atmosphere. Using varying percentages, biochars are used to replace ordinary Portland cement (OPC) in cement pastes at a water/binder ratio of 0.35. Characterization methods include XPS, FTIR, SEM, TGA, BET, Raman, loss-on-ignition, setting, compression and water absorption tests.

Accelerated setting in biochar-modified cement pastes is attributed to chemical interactions between surface functional groups of biochars and calcium cations from OPC, leading to the early development of metal carboxylate and alkyne salts, alongside the typical calcium-silicate-hydrate (C-S-H). Also, metal chlorides such as calcium chlorides in biochars contribute to the accelerate setting in pastes. Lower compression strength and higher water absorption result from weakened microstructure due to poor C-S-H development as the high carbon content in biochars reduces water available for optimum C-S-H hydration. Amorphous silica contributes to strength development in pastes through pozzolanic interactions. With its optimal physiochemical properties, rice-husk biochars are best suited for cement replacement.

While biochar parent material properties have an impact on biochar properties, these are not investigated in this study. Additional investigations will be conducted in the future.

Carbon/silicon ratio, oxygen/carbon ratio, alkali and alkaline metal content, chlorine content, carboxylic and alkyne surface functional groups and surface areas of biochars may be used to estimate biochar suitability for cement replacement. Biochars with chlorides and reactive functional groups such as C=C and COOH demonstrate potential for concrete accelerator applications. Such applications will speed up the construction of concrete structures and reduce overall construction time and related costs.

Reductions in OPC production and agricultural waste deterioration will slow down the progression of negative environmental and human health impacts. Also, agricultural, manufacturing and construction employment opportunities will improve the quality of life in agricultural communities.

Empirical findings advance research and practice toward optimum utilization of biomass in cement-based materials.

Soybean is potentially a rich source of protein and lipids along with isoflavone. However, the use of soybean is limited due to presence of anti-nutritional factors such as trypsin inhibitor, phytic acid, etc. The present study aimed at evaluation of Harit soya seeds of different treatments such as soaking, dehulling, germination, soaking+roasting and roasting in order to enhance its quality.

Harit soya seeds were utilized were soaked overnight and subjected for dehulling, germination for 3 days as well as roasting followed by drying to obtain fine powder for quality evaluation.

Dehulling and germination produce significant (p < 0.01) increase in protein, crude fiber, total chlorophyll, ascorbic acid, total phenolics, flavonoids and isoflavones while fat was decreased non-significantly. The highest value of 12.4 mg/100g, 5.3 mgGAE/g and 6.6 mg/g for ascorbic acid, total phenolics and isoflavones was found in germinated seeds. Also, the effect of soaking, roasting and their combination lead to significant decrease in the functional properties of the seeds. Anti-nutritional factors were significantly (p < 0.01) reduced in all forms of treated seeds while pepsin and trysin digestibility was enhanced during soaking, dehulling and germination with maximum value of 72.6 and 25.8%, respectively in germinated seeds.

Improvement in quality of evergreen variety of soybean using cost effective traditional methods

Studies different forms of lac resin, viz. sticklac, seedlac and shellac by FT‐IR spectroscopy. Also compares the FT‐IR and DRIFT spectra of lac obtained from different host trees in an attempt to explain the differences in their physico‐chemical properties. Concludes that all lacs are a structurally similar class of compounds but differ in physico‐chemical behaviour due to minor compositional differences, especially with reference to hydroxylic content, long chain fatty acid content and unsaturation.

The purpose of this paper is to investigate the wettability and intermetallic (IMC) layer formation of Sn-3.0Ag-0.5Cu (SAC305)/CNT/Cu solder joint according to the formulation of solder paste because of different types of fluxes.

Solder pastes were prepared by mixing SAC305 solder powder with different flux and different wt.% of carbon nanotube (CNT). Fourier transform infrared spectroscopy was used to identify functional groups from different fluxes of as-formulated solder paste. The solder pastes were then subjected to stencil printing and reflow process. Solderability was investigated via contact angle analysis and the thickness of cross-sectionally intermetallic layer.

It was found that different functional groups from different fluxes showed different physical behaviour, indicated by contact angle value and IMC layer thickness. “Aromatic contain” functional group lowering the contact angle while non-aromatic contain functional group lowering the thickness of IMC layer. The higher the CNT wt.%, the lower the contact angle and IMC layer thickness, regardless of different fluxes. Relationship between contact angle and IMC layer thickness is found to have distinguished region because of different fluxes. Thus it may be used as guidance in flux selection for solder paste formulation.

However, detail composition of the fluxes was not further explored for the scope of this paper.

The quality of solder joint of SAC305/CNT/Cu system, as indicated by contact angle and the thickness of IMC layer formation, depends on existence of functional group of the fluxes.

The purpose of this paper is to discuss the chemical characterization of failures and process materials for microelectronics assembly.

The analytical techniques used for chemical structures and compositions including Fourier transform infrared spectrometer (FTIR), scanning electron microscopy, and energy‐dispersive X‐ray spectroscopy are conducted.

The residues on the golden finger are identified to be the flux used in the assembly processes. Besides, the contaminants on the processed and incoming connector pins are verified to be polyamides (–CONH functional groups) from housing material's residue. Three liquid fluxes used in wave soldering are analyzed by their chemical structure. One flux showing the OH groups at 3430 cm⁻¹ indicates higher acid contents. This consists with the acidic values specified by the supplier. Also, the solder mask under study has ever appeared peeled‐off issue. The FTIR spectra results indicated 62.2 percent degree of curing while vendor's spec is above 70 percent.

The establishment of the Infrared spectra database for fluxes and process materials help determine the root cause of the contaminants to reduce re‐occurrence of similar problems and thus enhance the manufacturing capability. The infrared spectrophotometry technique can be used by professional original design manufacturing and/or electronics manufacturing service, providers to investigate board/component defects during product pilot run stage and volume production.