In order to improve the mechanical properties of the ultra‐high molecular weight polyethylene (UHMWPE) fiber‐reinforced high‐density polyethylene (HDPE) composite, carbon nanotube (CNT) was grafted ...on the UHMWPE fiber. The UHMWPE fiber/HDPE composite was prepared by injection molding process, and the effects of CNT contents on the mechanical properties of composite materials were studied. The results show that the mass fraction of CNT will significantly affect the mechanical properties of the composite. When the CNT content is 4 wt%, the tensile strength, tensile modulus, flexural strength, flexural modulus, and impact strength of the UHMWPE fiber/treated CNT/HDPE composite increased compared to the UHMWPE fiber/CNT/HDPE composite and UHMWPE fiber/HDPE composite. When the CNT content is 4 wt%, the above‐mentioned performance is the best. Pull‐out and fracture, bridging effect, and crack deflection effect are the main mechanisms of CNTs in UHMWPE fiber/HDPE composites. This study provides new insights into the interface design of UHMWPE fiber/HDPE composites and paves the way for their further development.
Ternary NiCoFe mixed-metal oxides (NCF-MMOs) with different Ni/Co/Fe ratios were successfully synthesized through a hydrotalcite-like precursor route by co-precipitation of appropriate amounts of ...metal salts from homogeneous solution, followed by calcination at 600 °C. X-ray diffraction (XRD) patterns revealed the formation of well crystalline layered double hydroxides (LDHs), particularly at the M
2+
/M
3+
ratio of 3 : 1. Brunauer-Emmett-Teller (BET) analysis revealed that the resulting NiCoFe LDHs possessed large specific surface areas (66.9-93.8 m
2
g
−1
). The NCF-MMO (1 : 2 : 1) samples were demonstrated to be formed by the aggregation of regular cubes with an edge length of about 2 μm, and each cube was accumulated with many fine particles with a size of ∼130 nm. UV-vis diffuse reflection spectroscopy (DRS) confirmed that the samples showed a broad absorption in the visible-light region (450-750 nm), with a low band gap of 2.33-2.77 eV. The calcined samples with a Ni/Co/Fe molar ratio of 1 : 2 : 1 possessed the best photocatalytic activity with 96.8% degradation of methylene blue (MB) dye under visible light irradiation for 4 h, which exceeded those of commercial P25 TiO
2
, binary NiFe mixed-metal oxides and pure Fe
2
O
3
, CoO and NiO particles under the same conditions. NCF-MMO (1 : 2 : 1) also had a strong degradation effect on the non-dye pollutant phenol as well. Kinetic studies suggested that the degradation of MB followed a pseudo-first-order kinetic behavior. The photodegradation mechanism of NCF-MMOs was also discussed.
Ternary NiCoFe mixed-metal oxides have demonstrated higher photoelectrocatalytic activity in degrading methylene blue (MB).
Milled wood lignin (MWL) was isolated from Dendrocalamus sinicus, an abundant bamboo variety in the earth, using Bjorkman method. Elucidation and quantification of the chemical structures for the ...isolated MWL have been facilitated by employing FT-IR and NMR techniques. The obtained results showed that the MWL consists of syringyl (S), guaiacyl (G), and p-hydroxyphenyl (H) units, indicating it as grass type (HGS) lignin. There is no significant change in structure (i.e. cleavage at α-O-4′ and β-O-4′ linkage) was observed. NMR techniques indicated that the isolated lignin was rich in β-O-4′ aryl ether substructures and syringyl (S) units. Furthermore, the sufficient understanding of the chemical structure of the lignin benefits their effective utilization towards the production of renewable biomass and biofuels.
The treatment, disposal, and resource utilization of waste mud are challenges for engineering construction. This study investigates the road performance of waste mud–solidified soil and explains how ...solidifying materials influence the strength and deformation characteristics of waste mud. Unconfined compressive strength tests, consolidated undrained triaxial shear tests, resonant column tests, and consolidation compression tests were conducted to evaluate the solidification effect. The test results show that with an increase in cement content from 5 to 9%, the unconfined compressive strength of the waste mud–solidified soil increased by over 100%, the curing time was extended from 3 to 28 days, and the unconfined compressive strength increased by approximately 70%. However, an increase in initial water content from 40 to 60% reduced the unconfined compressive strength by 50%. With the increase of cement content from 5 to 9%, the cohesion and friction angles increased by approximately 78% and 24%, respectively. The initial shear modulus under dynamic shear increased by approximately 38% and the shear strain corresponding to a damping ratio decay to 70% of the initial shear modulus decreased by nearly 11%. The compression coefficient decreased by approximately 55%. Scanning electron microscopy and X-ray diffraction tests showed that a higher cement content led to the formation of more hydration reaction products, especially an increase in the content of AlPO4, which can effectively fill the pores between soil particles, enhance the bonding between soil particles, and form a skeleton with soil particles to improve compactness. Consequently, the strength of the waste mud–solidified soil increased significantly while its compressibility decreased. This study can provide data support for dynamic characteristics of waste mud solidified soil subgrade.
Collective-owned construction land (CCL) marketization is an important driving force for the rapid development of China’s rural economy and society. Recognizing the trends and logic of its ...institutional changes is important for better understanding the central-local interrelation and the new-round CCL reform. Throughout the process of rural land reform since China’s reform and opening up, together with the unified policy guidance from the central government, the diversity of local practices and the trend of convergence in the development process deserve attention. Based on the institutional isomorphism theory, this paper analyzes the evolution of the CCL system in Shunde, Guangdong Province, and Wujiang, Jiangsu Province, since the 1990s, empirically demonstrating the trend of convergence based on diversity and exploring the underlying influencing mechanisms. The study finds that the evolutionary practice is characterized by the trend of ephemeral convergence represented by the shared cooperative and the land reservation reform and that of coeval convergence represented by the construction land nationalization. Top-down coercive pressure, horizontal imitative learning pressure, and governance-embedded normative pressure jointly shape the evolutionary convergence. This paper argues that the diversity of local experiments should be allowed and encouraged based on local characteristics. Policy flexibility should be further considered by the central government when formulating uniform policies for local adaptability.
The study of geography is centered on the regional system of the human-land relationship, and the core of the study of the geographical system of the human-land relationship is land use change. Land ...use is the most direct manifestation of human activities, accompanied by changes in land cover. This is the most appropriate entry point to reveal the evolution of human-land relationships. The past 300 years have been the most intense period of social change in China and the United States. In this study, we investigated the differences and evolution of human-land relations between China and the United States from the perspective of land cover change. We found: (1) Cultivated land, forest land, and grassland areas in China and the United States have changed significantly in the past 300 years. The cultivated land area has generally increased, and the extent of forest land and grassland has declined. According to the speed of land cover change, it can be roughly divided into three different stages. The change in cultivated land in China is mainly based on the enhancement of cultivation intensity. The change in cultivated land in the United States is mainly based on expansion of cultivated land. (2) The difference in land cover change between China and the United States in the past 300 years is mainly caused by the difference in social development, interpreting human-land relationships with honest feedback and social feedback. In general, with the continuous development of land, environmental issues have become increasingly prominent, and people’s awareness of environmental protection has also increased. (3) The evolution of human-land relations in China and the United States has been influenced by natural and social factors for nearly 300 years. China is dominated by population, whereas the United States is dominated by technology. The relationship between humans and land differs between the two countries in some respects, with similarities in other areas. In both countries, this relationship can be characterized by the stages of relying on the environment, understanding the environment, transforming the environment, and protecting the environment. This evolution is in line with the law of social development, according to which human beings constantly recognize, utilize, and adapt to nature.
Alongside the proceeding of rural land system reform in China, it becomes more and more critical to conduct policy performance evaluations on collective-owned construction land for profitable use to ...reflect the achievements and deficiencies of the reform. Traditionally, land policy performance evaluation is based on the theory of “policy-performance”, which fails to explain the mechanism of transaction costs. From the perspective of spatial planning, land use and the spatial form shaped by land development management and control are a representation of land property rights, as well as an expression of land policy performance. Thus, a correct understanding of the role of spatial form in the relationship between land policy and land performance is of great significance in accurately evaluating land policy performance and further improving land policies. Focusing on the interrelation among the three factors, this article highlights and elaborates on the intermediary role of spatial form between land property rights and land policy performance and puts forward the analytical framework of “land property right–spatial form–land policy performance”. It then takes the case of Wujiang District of Suzhou in southern Jiangsu Province to prove the effectiveness of this analytical framework. The outcome of this study can serve as a supplement to “policy-performance” theory, which refines and deepens the analysis of transaction costs from the perspective of spatial planning. It may also help deepen the recognition of land policy performance through visualized presentations, providing a new perspective for performance evaluation in quantitative and qualitative ways.
•Rabies deaths were 13,743.44 (95% uncertainty interval: 6019.13-17,938.53) in 2019.•The global disease burden of rabies had declined over the past 30 years.•The disease burden of rabies was closely ...related to the sociodemographic index level.
Rabies is an acute lethal infectious disease caused by a lyssavirus infection. In 2018, the World Health Organization proposed a global strategic plan to end human rabies deaths by 2030. However, systematic studies on the global rabies disease burden and epidemiological trends are scarce.
We extracted the disease burden and epidemiological data of rabies worldwide in the preceding 30 years from the Global Burden of Disease Study 2019 and performed a comprehensive analysis.
In 2019, the incident cases of rabies worldwide were 14,075.51 (95% uncertainty interval: 6124.33-21,618.11), and the number of deaths was 13,743.44 (95% uncertainty interval: 6019.13-17,938.53), both of which were lower than that in 1990. With the improvement of the sociodemographic index, the incident cases, the number of deaths, age-standardized incidence rate, age-standardized incidence death rate, and disability-adjusted life years of rabies all showed downward trends. Adolescents and adults aged <50 years represented the majority of rabies cases worldwide.
The global disease burden of rabies has declined over the past 30 years. Furthermore, the disease burden of rabies was closely related to the sociodemographic index level.
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