A reactive compatibilization with the compound containing four epoxy groups for polylactic acid/poly(butylene adipate-co-terephthalate)/thermoplastic starch ternary bio-composites.

How to effectively improve the poor interfacial adhesion between polylactic acid/poly(butylene adipate-co-terephthalate) (PLA/PBAT) matrix and thermoplastic starch (TPS) is still a challenge. Therefore, this work aims to introduce a convenient method to enhance the performance of PLA/PBAT/TPS blend by melt reactive extrusion. Here, using 4,4'-methylene-bis(N,N-diglycidyl-aniline) (MBDG) containing four epoxy groups as a reactive compatibilizer, and respectively using 1-methylimidazole (MI) or triethylenediamine (TD) as a catalyzer, serial PLA/PBAT/TPS ternary bio-composites are successfully prepared via melt reactive extrusion. The results showed that, under the catalysis of organic base, especially MI, the epoxy groups of MBDG can effectively react with hydroxyl and carboxyl groups of PLA/PBAT and hydroxyl groups in TPS to form chain-expanded and cross-linked structures. The tensile strength of the composites is increased by 20.0 % from 21.1 MPa, and the elongation at break is increased by 182.4 % from 17.6 % owing to the chain extension and the forming of cross-linked structures. The molecular weight, thermal stability, crystallinity, and surface hydrophobicity of the materials are gradually improved with the increase of MBDG content. The melt fluidity of the composites is also improved due to the enhancement of compatibility. The obtained PLA/PBAT/TPS materials have the potential to be green plastic products with good properties.

Research on industrial structure adjustment and spillover effect in resource-based regions in the post-pandemic era.

Resource-based regions support national economic development and are essential sources of basic energy and raw materials. In the post-pandemic era, however, there are practical situations to deal with, such as a fractured industrial chain, a weaker industrial structure, and a sharp reduction in economic benefits. Based on data collected from 68 cities in China, from 2010 to 2021, with 816 observations, this paper explores the industrial development process of resource-based regions in China and the change in the toughness of the industrial structure under the impact of COVID-19. The paper studies and analyzes industrial development trends, industrial structure toughness, and spatial spillover effects. The methods used are the Markov chain model and the Industrial Structure Advancement Index. By building the spatial Dubin model, the paper analyzes the spatial spillover effect of regional industrial development. It decomposes the spillover effect using the partial differential model based on regression. The results show that, during the study period, the comprehensive development level of industries in resource-based regions in China was slowly improving and tended to stabilize after entering the post-pandemic era. The evolution of an advanced industrial structure is significantly heterogeneous among regions, and each region has different toughness. The impact of COVID-19 has reduced the toughness of China's resource-based regions' industrial structure. The spatial spillover effect of regional industrial development is significant. Labor force, technology input, and industrial-structure optimization have different impacts on the industrial development of neighboring regions. In the post-pandemic era, China has used new management methods for more innovation. In order to achieve low-carbon, environmental protection, and sustainable development of resources, realize the rapid recovery of the toughness of industrial structure in China's resource-based cities, and reduce the impact of the COVID-19 pandemic, China proposes to expand the supply of resources, improve the allocation of resources, optimize the direction, promote the rational flow and efficient aggregation of various factors, and enhance the impetus for innovation and development.

Impact of environmental effect on industrial structure of resource-based cities in western China.

Improving the environment and optimizing industrial structure are the primary tasks of resource-based cities in western China. This paper analyzes the impact mechanism and path of environmental effect on the industrial structure using the panel data of 37 prefecture-level resource-based cities in western China from 2008 to 2019. The results show that the environmental effect is beneficial for optimizing the industrial structure of resource-based cities in western China. The economic development and resource endowment amplify the positive impact of the environmental effect on industrial structure upgrades. In resource-based cities with different growth cycles, environmental effect has different impact on industrial structure upgrades. Technological innovation of enterprises and public awareness of environmental protection are effective paths for environmental effect to promote industrial structure upgrading. Therefore, it is really crucial to promote environmental protection, identify regional characteristics, and enhance departmental cooperation for resource-based cities in western China, realizing industrial structure upgrades and sustainable economic development.

Interfacial Reaction-Induced Defect Engineering: Enhanced Visible and Near-Infrared Absorption of Wide Band Gap Metal Oxides with Abundant Oxygen Vacancies.

Modified metal oxides with narrow band gaps have attracted great interest in photothermal applications because of their wide optical absorption range. To tune wide band gap metal oxides into visible and near-infrared responsive materials, we deploy a unique interfacial reaction-induced defect engineering approach, which enables us to effectively modify the electronic structure of metal oxides by introducing oxygen vacancy defects. This approach reduced the band gap of zirconia from 5.47 to 1.38 eV, accompanied by a color change to black. More importantly, it is not limited by the size of the metal oxides, and bulk black zirconia was successfully obtained for the first time. It has been demonstrated that the prepared black zirconia can be applied as an effective photothermal therapy agent in vitro. Additionally, the interfacial reaction-induced defect engineering approach has been successfully extended to enhance the optical absorption of other metal oxides.

Effect of indium doping on motions of 〈a〉-prismatic edge dislocations in wurtzite gallium nitride.

The influences of indium doping on dynamics of 〈a〉-prismatic edge dislocation along [Formula: see text] shuffle plane in wurtzite GaN have been investigated employing classical molecular dynamics (MD) simulations. The dependence of dislocation motion mode and dislocation velocity on indium doping concentration, temperature, and applied shear stress was clarified. Moreover, the simulation results were further analyzed using elastic theory of dislocation and thermal activation theory of dislocation motion, showing excellent agreement with the simulation. Our findings help gain deep insights into modifying dynamic behaviors of TDs through the alloying doping and offer generic tools to the study of other wurtzite materials of promising application prospects, such as AlGaN and ZnO.

Experimental Investigation on Pore Structure Characterization of Concrete Exposed to Water and Chlorides.

In this paper, the pore structure characterization of concrete exposed to deionised water and 5% NaCl solution was evaluated using mercury intrusion porosity (MIP), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The effects of calcium leaching, fly ash incorporation, and chloride ions on the evolution of pore structure characteristics were investigated. The results demonstrate that: (i) in ordinary concrete without any fly ash, the leaching effect of the cement products is more evident than the cement hydration effect. From the experimental data, Ca(OH)2 is leached considerably with the increase in immersion time. The pore structure of concrete can also be affected by the formation of an oriented structure of water in concrete materials; (ii) incorporation of fly ash makes a difference for the performance of concrete submersed in solutions as the total porosity and the pore connectivity can be lower. Especially when the dosage of fly ash is up to 30%, the pores with the diameter of larger than 100 nm show significant decrease. It demonstrates that the pore properties are improved by fly ash, which enhances the resistance against the calcium leaching; (iii) chlorides have a significant impact on microstructure of concrete materials because of the chemical interactions between the chlorides and cement hydrates.

Study on the Carbonation Behavior of Cement Mortar by Electrochemical Impedance Spectroscopy.

A new electrochemical model has been carefully established to explain the carbonation behavior of cement mortar, and the model has been validated by the experimental results. In fact, it is shown by this study that the electrochemical impedance behavior of mortars varies in the process of carbonation. With the cement/sand ratio reduced, the carbonation rate reveals more remarkable. The carbonation process can be quantitatively accessed by a parameter, which can be obtained by means of the electrochemical impedance spectroscopy (EIS)-based electrochemical model. It has been found that the parameter is a function of carbonation depth and of carbonation time. Thereby, prediction of carbonation depth can be achieved.

Permeation Properties and Pore Structure of Surface Layer of Fly Ash Concrete.

This paper presents an experimental study on the nature of permeation properties and pore structure of concrete surface layers containing fly ash. Concretes containing different dosages of fly ash as a replacement for cement (15% and 30% by weight of total cement materials, respectively) were investigated. Concrete without any fly ash added was also employed as the reference specimen. Laboratory tests were conducted to determine the surface layer properties of concrete including chloride transport, apparent water permeability and pore structure. The results demonstrate that incorporation of fly ash, for the early test period, promotes the chloride ingress at the surface layer of concrete but substituting proportions of fly ash may have little impact on it. With the process of chloride immersion, the chloride concentration at the surface layer of concrete with or without fly ash was found to be nearly the same. In addition, it is suggested that the water permeability at the concrete surface area is closely related to the fly ash contents as well as the chloride exposure time. Pore structure was characterized by means of mercury intrusion porosimetry (MIP) test and the scanning electron microscopy (SEM) images. The modification of pore structure of concrete submersed in distilled water is determined by the pozzolanic reaction of fly ash and the calcium leaching effect. The pozzolanic reaction was more dominant at the immersion time of 180 days while the calcium leaching effect became more evident after 270 days.

[A 10-year-review (1998 - 2007) on 3449 cases of osteoporotic hip fractures: trend of hospitalization and inpatient costs].

OBJECTIVE: The purpose of this retrospective research was to analyze the trend of hospitalized prevalence in the past 10 years (1998 - 2007) and to estimate resource utilization associated with osteoporotic hip fractures, including hospital length of stay and inpatient costs in Guangzhou, China. METHODS: 3449 patients aged 50 years and older, hospitalized for primary diagnose of hip fractures in both hospitals in the past ten years were included in our study. Completed data was obtained retrospectively from the hospital medical records. Clinical parameters such as sex-specifics, hospital length of stay, inpatient costs, and the constitutions of the inpatient costs were analyzed with multiple statistics methods and regressions. RESULTS: Over the 10-year study period, the number of hospitalizations for hip fractures increased with a curve model. Male and female ratio was 1:1.95 with an average age of the patients as 76.32 +/- 9.52 years old. Average hospital length of stay was 23.59 +/- 13.48 days with no significant difference between males and females, years of admission and the different diagnoses. The number of hospitalization went to the top at the age of 70 to 79 years old (38.45%), followed by 80-89 years old (33.08%). Femoral neck fractures was significantly more than that of inter-trochanteric fractures in those patients aged 50 to 79 years (P < 0.01) but less than those intertrochanteric fractures aged 90 years and older (P < 0.05). Average inpatient costs is about 23.52 +/- 17.00 thousand Yuan (RMB) (femoral neck fractures is about 25.09 +/- 17.62 thousand Yuan and intertrochanteric fracture is 21.44 +/- 15.92 thousand Yuan) of which treatment costs (included implants, materials used in the theatre and routinely care of the wound) contributed 52%, pharmacy intervention 25%, operation 6%, ward expenditure 5%, radiology and physical investigation 5%, and chemistry test 4%. The inpatient cost went to a peak at the age of 60 - 69 years old and were significantly correlated with the hospital length of stay. The cost increased every year in the past 10 years by 6.18%. CONCLUSION: These results emphasized that the growing economic impact arising from the inpatient treatment of osteoporotic hip fractures and most of which related to treatment cost (include implants, materials used in the theatre and routinely care of the wound), and drugs and always correlated to length of hospital stay. Cost control should be paid more attention to the implants and drugs.