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In this study, the effects of adding mixtures of mono- and di-fatty acid glycerides and Tween 80 with different hydrophilic-lipophilic balance (HLB) values on the stability and whipping characteristics of cream were studied, and the hardness, whipping rate, apparent viscosity, stability, and microstructure of the cream samples were detected. The results showed that with the increase in HLB value, the apparent viscosity of the emulsion decreased, and shear thinning occurred in all cream samples. The centrifugal creaming rate and turbiscan stability index (TSI) decreased first and then increased, and so did the absolute value of zeta potential. The results of whipping characteristics analysis showed that with the increase in HLB value, the whipping time and whipping rate of cream decreased, and the hardness after whipping increased first and then decreased, reaching a maximum of 1 150.1 g when the HLB value was 9. At HLB values in the range of 9–11, cream exhibited a shorter whipping time, higher whipping hardness, appropriate whipping rate, and good mounting performance with no collapse or deformation. Meanwhile, the microstructure showed that the size of the cream bubbles was relatively uniform after whipping, and the fat globules around the bubbles were dense and close to each other, thus forming a better network structure to protect the bubbles and make the foam more stable. Therefore, the HLB value of mixed emulsifiers should be controlled in the range of 9–11 to obtain cream with good stability and whipping characteristics.

Since the use of additives supplies the different properties required to develop better-performing roadways, modification with additives has been used as one of the attractive alternatives when the base asphalt does not satisfy the requirements for traffic load, climate variations, and paving structure. This study evaluates the effect of additive materials of improving the ability of the surface layer to withstand permanent deformation. In addition, it discusses to what extent using waste materials as additive materials affects permanent deformation resistance and the extent of using waste materials as alternative modifiers to commercial polymers to enhance permanent deformation resistance. In this study, the simulation using the ABAQUS program under the conditions of using different percentages of the additives, changes in the thickness of the surface layer, and increasing the temperature on permanent deformation of the asphalt layer was investigated. The simulation results showed that using modified mixtures improved the Hot Mix Asphalt HMA's properties and decreased the mixtures' temperature susceptibility, which manifested as a decrease in permanent deformation (lower rutting depth) when compared to an unmodified mixture. Furthermore, using waste materials led to the greatest decrease in permanent deformation among all models.

[Objective] Cultivated land resources are the main material basis for food production. Analyzing the characteristics of the spatial and temporal changes of cultivated land resources in the typical black soil region has important reference value for optimizing the allocation of cultivated land resources. [Methods] Based on the land use data of four periods from 1986 to 2020 in the typical black soil region of Northeast China, the quantitative change of cultivated land resources characterized by the increase and decrease of cultivated land area were revealed. Taking the change of cultivated land spatial pattern as the breakthrough point, the characteristics of cultivated land resource quality change represented by site conditions were analyzed. On this basis, the driving factors of spatial and temporal changes of cultivated land resources were analyzed. [Results] (1) From 1986 to 2020, the area of cultivated land in the typical black soil region in Northeast China had been increasing, with a net increase of 2.51 × 104 km2, of which the largest increase occurred from 1986 to 2000, and the areas with more dramatic changes in cultivated land were concentrated in the southern foot of the Greater Xing’an Mountains, the Sanjiang Plain, and the areas surrounding the three provincial capital cities of the region; (2) For more than 30 years, due to the continuous movement of the center of gravity of the cultivated land to the northeast, the average temperature of the cultivated land area in the typical black soil region decreased by 0.20℃, the average humidity increased by 0.12%, and the average slope showed the change characteristics of first increasing and then decreasing; Compared with the transferred-out farmland, the temperature condition of the farmland that was transferred in was always poor, the humidity condition was generally superior, the slope condition was poor at the beginning, and better than the transferred-out farmland at a later stage; (3) In areas with low temperature (-1℃-2℃), high humidity (67%-71%), and high slope (15°-79°), cultivated land was frequently transferred in and out, with dramatic changes. [Conclusion] From 1986 to 2020, the area of cultivated land in the black soil region continued to increase, and the center of gravity continued to move northward and eastward, making the overall temperature conditions of cultivated land area worse, the humidity conditions better, and the terrain conditions basically stable. This result provides a reference for accurately judging the grain production capacity of the black soil area and scientifically utilizing and protecting the black soil.

[Objective] The conservation of black soil is an important measure for ensuring national food security and promoting ecological civilization construction. The understanding, attention, and efforts in black soil protection urgently need to be improved. [Methods] Using a literature analysis method, this study comprehensively summarized the natural, productive, and ecological characteristics of black soil, and systematically and structurally reviewed the situation faced by black soil conservation and proposed strategies to address these issues. [Results] The study revealed that: (1) Black soil has unique soil formation conditions, strong productivity, and fragile ecological characteristics; (2) The situation of black soil protection is complex, which can be seen in the micro-scale element structure, meso-scale human-land relationship, and macro-scale regional development. Four main issues were identified: excessive land use, frequent soil degradation, severe population problems, and lagging economic development. (3) Black soil protection strategies should also start from the micro-scale technical system, meso-scale agricultural system, and macro-scale policy system, adopt interdisciplinary methods that combine natural and social sciences, as well as integrate technical, economic, and institutional means to ensure the effectiveness, strength, and sustainability of black soil protection work. [Conclusion] Black soil has both natural and cultural characteristics, and the protection work should take into account the requirements of both the natural ecosystems and the human-land systems, and being carried out comprehensively.