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Application of foam in enhanced oil recovery requires a production of foam that is strong and stable enough to withstand a long period. There are numerous factors that may affect the performance of foam, among which is temperature. Therefore, this study aims to observe the foam performance at different temperature by evaluating the foamability and the stability of the foam.

In this study, bulk foam test using FoamScan was conducted to examine the effect of temperature on foam in the presence of crude oil. Nitrogen gas was sparged through the mixture of crude oil, an in-house developed surfactant, and sodium chloride solution as the brine at different temperatures to produce foam at a certain height. The crude oil was extracted from an oilfield in East Malaysia and the in-house developed surfactant was a mixture of amphoteric and anionic surfactants. A camera continuously recorded the height of foam during the generation and the collapse of the foam. The foamability and foam stability properties of each sample were taken as the indicators for foam performance. Furthermore, the entering, spreading and bridging analysis was run to observe the effect of the presence of crude oil on foam performance.

In general, the higher the temperature, the less stable the foam is. As the stability of foam is associated with the rate of liquid drainage, it was observed that as temperature increases, the rate of liquid drainage also increases. On the other hand, the entering, spreading and bridging analysis shows that there is entering of oil droplet happening on the interface of foam film that may promote the rupture of the foam film even more.

It was found that the temperature has a small impact on foamability, whereas the foam stability was significantly affected by the temperature. Therefore, it can be concluded that foamability is not necessarily interrelated to foam stability, contradicting to the findings of few authors.

This article aims to consider the use of high pressure processing in order to gain functional advantages through proteins structure control. High pressure processing has been used to produce high-quality food with extended shelf life and could also be used to modify foods functionality.

The effect of high pressure on protein structure and functionality is looked at and comparisons are made with heat effect in places. β-lactoglobulin and whey proteins are mainly taken as examples.

A controlled partial protein unfolding through mild high pressure processing could lead to a range of intermediate molecular structures. These are distinct from the native and completely unfolded structure and have been referred to as molten globules. The partly unfolded molecular states, hence, are postulated to have increased functionality and could be interesting for the food industry.

The opportunity and challenges represented by these theoretical elements are discussed. In particular, the effect of protein concentration and aggregation is emphasised.

For a better understanding of the preferences and differences of young consumers in emerging wine markets, this study aims to propose a clustering method to segment the super-new generation wine consumers based on their sensitivity to wine brand, origin and price and then conduct user profiles for segmented consumer groups from the perspectives of demographic attributes, eating habits and wine sensory attribute preferences.

We first proposed a consumer clustering perspective based on their sensitivity to wine brand, origin and price and then conducted an adaptive density peak and label propagation layer-by-layer (ADPLP) clustering algorithm to segment consumers, which improved the issues of wrong centers' selection and inaccurate classification of remaining sample points for traditional DPC (DPeak clustering algorithm). Then, we built a consumer profile system from the perspectives of demographic attributes, eating habits and wine sensory attribute preferences for segmented consumer groups.

In this study, 10 typical public datasets and 6 basic test algorithms are used to evaluate the proposed method, and the results showed that the ADPLP algorithm was optimal or suboptimal on 10 datasets with accuracy above 0.78. The average improvement in accuracy over the base DPC algorithm is 0.184. As an outcome of the wine consumer profiles, sensitive consumers prefer wines with medium prices of 100–400 CNY and more personalized brands and origins, while casual consumers are fond of popular brands, popular origins and low prices within 50 CNY. The wine sensory attributes preferred by super-new generation consumers are red, semi-dry, semi-sweet, still, fresh tasting, fruity, floral and low acid.

Young Chinese consumers are the main driver of wine consumption in the future. This paper provides a tool for decision-makers and marketers to identify the preferences of young consumers quickly which is meaningful and helpful for wine marketing.

In this study, the ADPLP algorithm was introduced for the first time. Subsequently, the user profile label system was constructed for segmented consumers to highlight their characteristics and demand partiality from three aspects: demographic characteristics, consumers' eating habits and consumers' preferences for wine attributes. Moreover, the ADPLP algorithm can be considered for user profiles on other alcoholic products.

This paper aims to understand the effect of extrusion conditions on the degree of foaming of polylactic acid (PLA) during three-dimensional (3D) printing. It was also targeted to optimize the slicing parameters for 3D printing and to study how the properties of printed parts are influenced by the extrusion conditions.

This study used a commercially available PLA filament that undergoes chemical foaming. An extrusion 3D printer was used to produce individual extrudates and print samples that were characterized using an optical microscope, scanning electron microscope and custom in-house apparatuses.

The degree of foaming of the extrudates was found to strongly depend on the extrusion temperature and the material feed speed. Higher temperatures significantly increased the number of nucleation sites for the blowing agent as well as the growth rate of micropores. Also, as the material feed speed increased, the micropores were allowed to grow bigger which resulted in higher degrees of foaming. It was also found that, as the degree of foaming increased, the porous parts printed with optimized slicing parameters were lightweight and thermally less conductive.

This study fills the gap in literature where it examines the foaming behavior of individual extrudates as they are extruded. By doing so, this work distinguishes the effect of extrusion conditions from the effect of slicing parameters on the foaming behavior which enhances the understanding of extrusion of chemically foamed PLA.

This review provides an overview of the applications of Bambara groundnuts in various food products. The genetic diversity, physical properties and chemical compositions of the crop are also elucidated.

This paper critically reviewed the physicochemical properties and applications of Bambara groundnuts from recent literature.

Bambara groundnut (Vigna subterranea) is a drought-tolerant crop from West Africa that contains not only carbohydrates and fats but is also high in protein. The cultivars of Bambara groundnut can be distinguished by the colours of seeds, which range from red, blue-eye, brown and black-eye. Bambara groundnuts contain carbohydrate (57–67%), protein (15–25%), fat (4–8%), fibre (1.4–1.5%) and ash (2.9–4%). As a percentage of protein, the essential amino acids, lysine, methionine and cysteine are relatively high in Bambara groundnuts. Meanwhile, linoleic, palmitic and linolenic acids are the fatty acids present in this crop.

Several studies have shown that Bambara groundnuts can be used as fat substitutes, emulsifiers, water binders, bulking agents and thickeners due to its water and oil absorption properties, gelling, pasting, emulsifying and foaming abilities. Bambara groundnuts are used in the development of many intermediate or final products like flour blend, cookies, bread and fermented milk. It has a positive impact on the overall proximate, functional, mineral and amino acid profiles of the food products.

Despite its high nutrient density, Bambara groundnuts are an underutilised legume due to unavailability and lack of knowledge among consumers on its benefits. There is a need to promote the use of Bambara groundnuts as a future food.

This paper aims to use this method to explore a new approach and possible technical optimal design for lubricant formulation.

The component of the developed oil was determined based on the physical and chemical properties of the base oil and the tribological properties. The analytic hierarchy process (ANP) method and SuperDecisions software were used for hydraulic oil modeling and calculation while taking performance index, work circumstance and economy into consideration.

The hydraulic oil formulation can be optimized using the ANP method, where the technical performance, economy and working circumstances of the hydraulic oils were taken into consideration in the evaluation system. The experiment analyzed and scored and screened the hydraulic oil formula in an objective and comprehensive manner.

The experiments showed that the newly developed hydraulic oils could meet the performance requirements for new energy vehicles equipped with hybrid hydraulic engines.

A series of sulfate-based Gemini anionic surfactants were synthesized via etherification, ring opening and sulfation reactions using epichlorohydrin, fatty alcohol, ethylene glycol and chlorosulfonic acid as the main raw materials. Orthogonal experiments for 1,8-bisalkoxymethylene-3,6-dioxin-1,8-octane disulfate were performed on the sulfation reaction to determine the optimal reaction conditions.

A series of sulfate-based Gemini anionic surfactants were synthesized via etherification, ring opening and sulfation reactions using epichlorohydrin, fatty alcohol, ethylene glycol and chlorosulfonic acid as the main raw materials. Orthogonal experiments for 1,8-bisalkoxymethylene-3,6-dioxin-1,8-octane disulfate were performed on the sulfation reaction to determine the optimal reaction conditions. The structures of the intermediate and final products were characterized by FT-IR (Fourier transform infrared spectroscopy analysis), ¹H-NMR (proton nuclear magnetic resonance spectroscopy) methods. The thermal performance of surfactants was analyzed using thermogravimetric analysis (TGA). The thermogravimetric results showed that the sulfate-based Gemini surfactants had good heat resistance (the thermal decomposition temperature of which was in the range of 140∼170?). The Krafft point, surface tension, foaming, Hydrophile–Lipophile Balance Number (HLB), emulsifying, wetting, and lime-soap dispersing performance were measured by visual observation, hanging drop method, aqueous surfactant solution method and Borghetti–Bergman method, respectively. The results have shown that all the sulfate-based Gemini surfactants had good water solubility and lime-soap dispersing ability. When spacer group was -(CH2)2-, with the increase of the carbon chain length from C12 to C14, the micellar concentration critical micelle concentration and surface tension (CMC) gradually increased from 8.25 × 10^–4 mol/L to 8.75 × 10^–4 mol/L and 27.5 mN/m to 30.9 mN/m, respectively. Also, the sulfate-based Gemini surfactants with the different length of the spacer group had a different effect on their performance on foaming properties and foam properties, HLB and emulsifying ability and wetting ability.

In view of the important role of the spacer group and the general use of anionic surfactants in oil fields, this article considers the preparation of a series of sulfate-based Gemini surfactants by changing the spacer group and the chain length of the hydrophobic group and evaluating their surface activity, and finally its Kraffi, on the foam properties, HLB value, emulsifying performance, lime soap dispersing ability etc.

Sulfate-based Gemini surfactants have broad application prospects in the fields of oil and gas exploitation, environmental protection, chemistry and daily chemical industry and so on.

The purpose of this paper is to study methods of reacting the surface of the particles of silica sols with silanes, primarily gamma‐glycidoxypropyltrimethoxysilane (GPTMS) and study some basic properties of the modified sols and the nature and structure of the silane groups attached to the particle surface.

The surface of the silica particles was modified by reacting the silica sols with aqueous solutions of silanes, chiefly GPTMS. The presence and structure of silane groups on the particle surface were established by Si‐NMR and C‐NMR, respectively.

Several silanes were studied but silica sols could be readily modified only with GPTMS and glycidoxypropylmethoxydiethoxysilane (GPMDES), most readily if the silanes were pre‐hydrolysed in water. Higher degrees of silylation were preferably done by continuous addition of silane. Lower degrees of modification can be achieved at room temperature by the stepwise addition of the silane solution. The silylation of the silica surface with GPTMS significantly reduces the number of charged surface groups and silanol groups. GPTMS binds covalently to the silica surface and the epoxy ring opens and transforms into a diol. Silica sols modified with GPTMS and GPMDES are stable toward aggregation.

Only organo‐reactive silanes were studied.

This is the first work to study the modification by silanes of silica aquasols with high concentrations of silica. The silane modification can extend the use of silica to areas of applications previously inaccessible to silica sols.