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The purpose of this study is to understand how printing parameters and subsequent annealing impacts porosity and crystallinity of 3D printed polylactic acid (PLA) and how these structural characteristics impact the printed material’s tensile strength in various build directions.

Two experimental studies were used, and samples with a flat vs upright print orientation were compared. The first experiment investigates a scan of printing parameters and annealing times and temperatures above the cold crystallization temperature (T_cc) for PLA. The second experiment investigates annealing above and below T_cc at multiple points over 12 h.

Annealing above T_cc does not significantly impact the porosity but it does increase crystallinity. The increase in crystallinity does not contribute to an increase in strength, suggesting that co-crystallization across the weld does not occur. Atomic force microscopy (AFM) images show that weld interfaces between printed fibers are still visible after annealing above T_cc, confirming the lack of co-crystallization. Annealing below T_cc does not significantly impact porosity or crystallinity. However, there is an increase in tensile strength. AFM images show that annealing below T_cc reduces thermal stresses that form at the interfaces during printing and slightly “heals” the as-printed interface resulting in an increase in tensile strength.

While annealing has been explored in the literature, it is unclear how it affects porosity, crystallinity and thermal stresses in fused filament fabrication PLA and how those factors contribute to mechanical properties. This study explains how co-crystallization across weld interfaces is necessary for crystallinity to increase strength and uses AFM as a technique to observe morphology at the weld.

This paper aims to evaluate diethylenetriamine (DETA) as an inhibitor on Q235 (Gr. D) steel in ammonia flue gas desulfurization (AFGD) system.

This research was carried out by weight loss, electrochemical measurements, scanning electron microscopy and X-ray photoelectron spectrometry. The effects of DETA on crystallization of ammonium sulfate and its co-crystallization were also investigated by X-ray diffraction and infrared spectroscopy.

The inhibition efficiency of DETA reached a maximum value of 98.96 per cent. DETA is postulated to adsorb on Q235 steel surface, resulting in the formation of a protective film by the accumulation of many flat particles, and the thickness of protective film is 8 μm. DETA had no effect on the crystallization of ammonium sulfate product.

DETA can be used in AFGD system as an inhibitor to protect the equipment well.

To prepare surfactants and use as pour point depressants for a waxy gas oil.

Some anionic surfactants (Calcium O, P.dioctyl benzene sulphonate and calcium hexadecyl benzene sulphonate) were prepared in the laboratory. The physicochemical characteristics were investigated. The adsorption behavior of these surfactants at air/solution and oil/solution interfaces were investigated by measuring the surface tension and interfacial tension as functions of concentration.

The surface parameters and free energies of micellization and adsorption confirm the decreasing and improving of pour point by prepared surfactants. It is found that there is a good relation between surface properties especially interfacial tension of the prepared surfactants and their efficiency in depressing the pour point. Also, the results indicating that anionic surfactants can be improved pour point of waxy gas oil.

Addresses long‐standing problem in the petroleum industry.

OVER the years lithium soap greases have earned a reputation of providing excellent service under a wide variety of operating conditions. Since their introduction in the early 1950s, lithium soap greases have served the market well, being especially suitable for both automotive and industrial multipurpose applications. Their performance has enabled them to grow in commercial importance to the point where they now account for over half the grease volume manufactured in the United States.

The purpose of this study is to address consumer’s preference of natural pigments over synthetic ones and their use in various product developments rather than using synthetic colours. A budding interest of using natural pigments has made researchers to explore several techniques for their stabilization and application in different food products.

In this review, four major natural pigments with potential health benefits have been studied. Betalins, carotenoids, anthocyanins and chlorophylls, in spite of having excellent bio-functional and therapeutic profile, are found to be unstable. Therefore, various nanoencapsulation techniques are used to increase their stability along with their therapeutic properties.

Nanoencapsulation of natural pigments improves their stability, their effect on therapeutic properties and their application in different food products. These findings could be attributed to the encapsulating material as it acts as a barrier and ushers changes in the matrix of natural pigments. Also, nanoencapsulation not only increases stability but also provides several health benefits such as anti-inflammation, anti-cancer, anti-allergic and anti-thrombotic properties.

This paper highlights the openings for the use of nanoencapsulation of natural pigments to stabilize them and use them as a potential colourant and functional ingredient in different food products. Phenols, carotenoids and antioxidant activity are the major factors that are responsible for promoting several health benefits.