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The most recent and prestigious scientific research shows that nitrogen leaching caused by over-used nitrogen fertilizer rapidly acidifies all soil types in China, revolutionizing the basic understanding of the mechanism of soil acidification. The purpose of this paper is to study the impact of nitrogen on soil acidity over the long run, which is the shadow price of nitrogen.

In a discrete dynamic programming model, this paper compares the nitrogen application and soil pH between optimal nitrogen control that takes the shadow price of nitrogen into consideration and myopic nitrogen control that ignores that shadow price. Using a five-year panel experimental data on a rapeseed-rice rotation, this paper simulates and numerically solves the dynamic model.

Both theoretically and empirically, this paper shows that the over-use of nitrogen and the decline in soil pH are explained by ignorance of the shadow price of nitrogen. Compared with optimal nitrogen control, myopic nitrogen control applies more nitrogen in total, resulting in lower soil pH. In addition, over-use in the first season contributes to soil acidification and the carry-over effects mitigate that problem.

This paper enriches the literature by extending the study of the environmental impact of nitrogen leaching to its impact on the long-term loss in agricultural production, providing a new theoretical framework in which to study soil acidification rather than conventionally treating soil acidification as a secondary consequence of acid rain, and showing the possibility of using nitrogen control to mitigate soil acidification when lime applications are not feasible due to socio-economic constraints.

The purpose of this paper is to clarify the influence of bicarbonate, chloride and outer electrode potential on crevice corrosion occurrence and development of X70 steel.

The crevice corrosion behavior in NaHCO₃ and NaCl solutions was investigated through modeling and experiments. The electrode potential and current density distribution were simulated, and the acidification of crevice solution was monitored in situ.

The bicarbonate concentration and outer electrode potential remarkably influenced the occurrence of crevice corrosion. The former changes the passivation curves, and the latter alters the initial potential. Moreover, chloride concentration exerted minimal influence. The location of acidification and pitting occurrences depended on the potential difference between the outer electrode and electrode at the active dissolution current peak.

This study provides a better understanding of the crevice corrosion behavior and mechanism under natural conditions.

A novel compound was synthesized by cyclohexylamine, acetophenone and cinnamaldehyde through Mannich reaction in laboratory to use as corrosion inhibitor for steel in acidification process.

The corrosion and inhibition of 13Cr stainless steel in conventional acidification solution were investigated by electrochemical measurements and soaking experiments. The corrosion appearance was observed with scanning electron microscope on the whole surface of 13Cr stainless steel in 20% HCl solution, and the protection film was confirmed on the surface in presence with inhibitor.

Results manifested that the inhibitor C23H27NO can effectively inhibit the corrosion reaction by forming an adsorption layer function as a barrier. Polarization curves indicated that the mixed inhibitor can reduce anodic dissolution and cathodic hydrogen evolution reactions simultaneously. The results of impedance measurements indicated that this inhibitor cannot change the corrosion mechanism of 13Cr stainless steel in 20% HCl solution. The results of the study can provide a theoretical basis for the application of 13Cr stainless steel in conventional acidification solutions during oil well acidification construction process.

A novel compound was synthesized by cyclohexylamine, acetophenone and cinnamaldehyde through Mannich reaction in laboratory to use as corrosion inhibitor for steel in acidification process. The corrosion and anti-corrosion mechanism of 13Cr steel in acid solution was proposed.

This paper aims to analyze the corrosion and corrosion inhibition of N80 in 10 per cent HCl + 8 per cent fluoroboric acid (HBF₄) solution for acidizing operation.

The corrosion rate, kinetic parameters (Ea, A) and thermodynamic parameters (ΔH, ΔS) of N80 steel in fresh acid and spent acid, 10 per cent HCl + 8 per cent HBF₄, 10 per cent HCl and 8 per cent HBF₄ solutions were calculated through immersion tests. The corrosion and inhibition properties were studied through X-ray diffraction and electrochemical measurements. The corrosion morphology of the corrosion product was examined by scanning electron microscopy (SEM).

The results demonstrated that the spent acid was the main cause of acidification corrosion, and the HBF₄ would cause serious corrosion to N80 steel. The results showed that the N80 steel was more seriously corroded in the spent acid than in fresh acid, and the hydrolysis of HBF₄ accelerates the dissolution process of N80 steel anode to control the corrosion reaction. The results showed that the acidification will definitely cause serious corrosion to the oil tube; therefore, necessary anti-corrosion measures must be taken in the acidification process.

The results showed that acidizing the formation with 10 per cent HCl + 8 per cent HBF₄ will definitely cause serious corrosion to the oil tube, especially when the spent acid flows back. Therefore, necessary anti-corrosion measures must be taken in the acidification process, especially in the spent acid flowback stage.

Operational energy use in buildings accounts for 28% of global energy demand. One method to reduce operational energy is upgrading old appliances to more efficient ones. In Australia, the most common residential heating type is reverse-cycle heating, followed by gas heating. This article aims to determine the energy balance resulting from a gas heating upgrade through a life cycle assessment (LCA).

Extensive primary data were collected for operational energy performance of 61 ducted gas heating upgrades. To address the scarcity of data on material composition, one ducted gas heater was deconstructed and assessed in terms of material composition (types and weights). The comparison between embodied energy and operational energy savings allows us to establish whether operational energy savings offset the embodied energy incurred with the upgrade. The end of life stage of the old appliance, as well as the production, construction and use stage of the new appliance were assessed.

The results show that the operational energy savings offset the following impact categories: global warming, ozone layer depletion, aquatic acidification, nonrenewable energy and carcinogens. Only the mineral extraction is not offset by the operational energy savings. The results clearly demonstrate that operational energy savings outweigh the embodied energy and therefore contribute positively to the environment.

This study is the first to focus on the LCA of building services through extensive primary data collection and a focus on a high number of appliances. This supports ongoing energy efficient upgrades in Australia and paves the way for further, similar studies to confirm or disprove these findings in other parts of the world.

The purpose of this paper is to evaluate effects of simultaneous supplementation of milk protein concentrate (MPC) as texture modifier and microencapsulated Lactobacillus paracasei (L. paracasei) (entrapped in gellan–caseinate) on physico-chemical, sensorial and microbial characteristics of yogurt during storage time.

L. paracasei cells were encapsulated through unique pH triggered gelation technique using combination of sodium caseinate-gellan gum as protective shell material. MPC was also used to improve physico-chemical indices of probiotic yogurt at different levels (0–3 percent).

The results showed that yogurt samples containing encapsulated L. paracasei showed lower post-acidification and higher viability. Samples containing encapsulated L. paracasei showed less syneresis amount, due to possible hydration of shell material, also application of MPC could reduce this attribute during storage time. The numbers of probiotic bacteria were remained above the recommended therapeutic minimum throughout the samples.

The findings suggest a practical ingredient in probiotic dairy product. Simultaneous usage of this kind of encapsulation via MPC enhanced sensorial and physical properties of probiotic yogurt while of no reduction in viable counts survival.

This study revealed usage of microcapsules of L. paracasei prepared by the gelation of sodium caseinate-gellan gum could be a suitable manner for delivery of probiotics in fermented dairy products like yogurt.

The purpose of this paper is to present a framework to assess the feasibility of fuel cells in both monetary and non‐monetary terms. It aims to develop an index is to compare different sources of energy in the residential market of the rural Appalachian region of the USA.

An index is developed to measure sustainable criteria and the factors that influence the user's decision‐making process of adopting an alternative energy. The sustainable criteria are obtained through a literature review, and the factors that influenced the decision‐making process are found through surveys to individuals who may potentially adopt alternative energies. After the index is developed, it is used to compare fuel cells and the conventional grid system using the specific case of a typical rural house.

The most relevant sustainable criteria found in literature are environmental impact, energy consumption, and cost. The factors that influenced the user's decision to adopt an alternative energy are cost, environmental impact, space, reliability, and safety. Those factors are combined in an index used to compare fuel cells and the coal‐fired grid system. According to the index, fuel cells have a slightly better rating than the grid system powered by a coal‐fired power plant; however, further development of fuel cells will be needed in order to be fully competitive.

The index developed is based on the rural Appalachian region of the USA. If the index is used in other locations, factors, and weights should be adjusted accordingly.

The framework discussed in the paper includes both the sustainable performance of the system, and the factors that influenced the user's decision to adopt an alternative energy. The latter has previously not been taken into consideration in the assessment of these types of technologies.

The factors considered in the paper will make a significant difference if alternative energies are to be considered as a viable alternative to traditional energy forms. The framework took a holistic approach, and considered factors such as cost, environment, energy consumption, reliability, maintenance, space and safety, that are deemed important by the final user.

Probiotics are known to extend health benefits and therefore may be included during yoghurt manufacture to enhance its prophylactic properties. Different probiotic strains may exhibit diverse biotechnological behaviour in association with yoghurt cultures, therefore interactive behaviour amongst probiotic and yoghurt cultures must be evaluated prior to their commercial application. This paper aims to assess the effect of inclusion of different probiotic cultures on various biotechnological (technological, dietetic and prophylactic) characteristics of yoghurt cultures.

Yoghurt was assessed for technological characteristics based on acidification and flavour production, dietetic characteristics based on proteolytic activity, vitamin synthesis and L (+) lactic acid production and prophylactic characteristics based on β‐galactosidase activity, antibacterial spectrum, viability in product as well as during gastro‐intestinal transit, intestinal colonization, immunomodulation, anti‐carcinogenicity and hypocholesterolemic effect.

Different probiotic cultures exhibited diverse technological, dietetic and prophylactic behaviour in association with yoghurt cultures. Functional properties of traditional yoghurt could be enhanced with the combined introduction of probiotic cultures such as Bifidobacterium bifidum, Bifidobacterium infantis and Lactobacillus acidophilus and the resultant product may be recommended for consumption as a dietary adjunct.

The paper shows that combined introduction of probiotic cultures such as B. bifidum, B. infantis and L. acidophilus, as microbial additives during the manufacture of yoghurt would result in a product with enhanced functional properties.

The quality of probiotic yogurt which is remarked as a healthy, therapeutic and nutritious food product strongly depends on starter types and their compositions; however, the choice of starter culture affects the taste, aroma and quality of the final product. Through this study, to obtain favorable quality attributes of probiotic yogurt, a mixture of two thermophilic/mesophilic starter cultures (YC- 350/YC- X16) was applied for fermentation.

The effects of starter mixture, probiotic Lactobacillus paracasei and storage time on quality indices, such as apparent viscosity, water holding capacity, syneresis, post acidification rate and probiotic viability (L. paracasei), were assessed through using a combined (mixture-process) statistical design.

The results revealed that changes in viscosity and syneresis depend on the amount of YC- X16. Acidification rate was more pronounced at higher levels of YC- 350 (1.22 per cent) in comparison to that in YC-X16 (1.08 per cent) during storage time. With respect to probiotic viability, L. paracasei count was more than 107 cfu/mL during refrigerated storage time. Moreover, a promotive effect of YC- 350 on L. paracasei proliferation was observed in this study.

The favorable yogurt, from qualitative aspects, was manufactured at 75:25 per cent ratio of YC- X16:YC- 350 in probiotic type yogurts. Therefore, the use of mixed starter cultures developed textural properties of probiotic yogurt beside L. paracasei survival.