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In this work, the low-power-loss Mn–Zn ferrite was prepared by the traditional ceramic sintering process. This sample shows the good wide-temperature stability of power loss (P cv). In the whole measurement temperature range of 25 - 120 °C, P cv s maintain less than 100, 682, and 1455 kW/m3 at 100 kHz/100 mT, 500 kHz/100 mT and 800 kHz/100 mT, respectively. The effect of uniaxial compressive stress on power loss at 100, 500 and 800 kHz was investigated. Stress has greater impact on P cv at high frequencies and P cv increases remarkably. To clarify the mechanism of stress on power loss, P cv was divided into three parts including hysteresis loss (P hv), eddy current loss (P ev) and residual loss (P rv), and the effect of stress on each part of loss was discussed. At the low frequency of 100 kHz, P cv is mainly contributed by P hv. The applied stress leads the local anisotropic stress and makes domain wall displacement more difficult, which is the reason of the increase of P hv. When frequency increases to 500 and 800 kHz, P ev and P rv become more important. The compressive stress is in favour of electron transfer between Fe3+ and Fe2+ in grains and electron tunnelling effect at grain boundaries, which leads to the decrease of resistivity. This is the origin of enhanced P ev under the compressive stress. The enhanced P rv is related to the enhanced electronic diffusion under the compressive stress. The clarification of the mechanism of stress on power loss is beneficial to develop new soft ferrite materials with low stress sensitivity for high-frequency applications. [ABSTRACT FROM AUTHOR]

• Extended urban travel time significantly promotes population outflow. • The individual tolerance differences in urban travel time extension are studied. • The city's tolerance differences in urban travel time extension are studied. • The concept of "transportation accessibility wage bargaining" is proposed. The rapid growth of urban transportation has led to increased pressure on transportation infrastructure in many urban areas. In this paper, we examine the relationship between urban travel time and decision-making on the spatial mobility of the labor force to optimize the labor space distribution pattern. Using Gaode map traffic congestion delay data, China Migrants Dynamic Survey (CMDS) data, and a conditional logit model, we conduct the first study to examine the relationship between travel time and residential location choice in 100 major cities in China, specifically from the perspective of traffic congestion. Our research finds that extended urban travel time significantly promotes population outflow, particularly among individuals with light family burdens, low job loyalty, and more choices. The population outflow effect formed by the extension of travel time shows the law of decreasing in line with the size of cities, with medium-sized cities experiencing the most serious inhibition effect. We also propose the concept of transportation accessibility wage bargaining and estimate the monetary compensation value to be ¥22.50 ($3.33) per day. This finding provides a quantitative reference for the design of a corresponding compensation mechanism to improve residents' willingness to stay in cities. [ABSTRACT FROM AUTHOR]

To meet the challenge of varied working temperatures of inductance components in new energy vehicle and 5G communication, the high- T C high-permeability MnZn ferrite with excellent temperature stability was developed by the addition of SnO 2. In this series of samples, initial permeability μ i maintains large values in a wide temperature range. With increasing the SnO 2 content, the temperature of the second permeability peak T sp decreases and meanwhile Curie temperature T C maintains as high as 160 °C. For the best sample with 6000 ppm SnO 2 , μ i at 25 °C is 7244 and exhibits the excellent temperature stability with the low specific temperature coefficient of 0.35 × 10−6 °C−1 between 25 and 130 °C. The addition of SnO 2 generates Fe2+ and adjusts the magneto-crystalline anisotropy constant K 1 = 0 point, which is responsible for the wide-temperature high permeability. The effect of SnO 2 addition on magnetization process has also been clarified. [ABSTRACT FROM AUTHOR]

The aim of this study was to identify the key provinces and sectors for energy conservation in China. First, this study extended the traditional multi-regional input–output (MRIO) table and established an energy consumption MRIO (EMRIO) model. The energy consumption linkages of 30 provinces in China were quantitatively analyzed by combining EMRIO model and modified hypothetical extraction method. Then, a new method is proposed to identify key provinces and sectors for energy consumptions. Finally, the key provinces and sectors of energy conservation and development encouraged in China were identified. The results of the total selection indices of key provinces showed that the key development-encouraged provinces were mostly developed provinces, such as Beijing (0.4), Shanghai (0.49), and Guangdong (0.54). The key energy conservation provinces were mostly less-developed provinces, such as Ningxia (2.56), Qinghai (2.14), and Xinjiang (1.88). According to the total selection indices of key sectors, the key energy conservation sectors in key energy conservation provinces were mostly Industry, Transportation, and Construction. The key development-encouraged sectors in key development-encouraged provinces were mostly Agriculture, Retail and Catering, and Others. • The traditional multi-regional input–output table was extended. • A new energy consumption multi-regional input–output model was established. • A new method was proposed to identify key provinces and sectors for energy consumption. • The energy consumption linkages of 30 provinces in China was quantitatively analyzed. • Key provinces and sectors for energy conservation in China were identified. [ABSTRACT FROM AUTHOR]

Highlights: [•] Large-diameter tube-like mesoporous TiO2 was synthesized using CTAB and urea. [•] A possible mechanism for the formation of tube-like mesoporous TiO2 was proposed. [•] Tube-like TiO2 was suitable for photodegradation of papermaking wastewater. [•] Tube-like TiO2 showed much higher photocatalytic activities than Degussa P25. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive system for assessing contaminant emissions, including the dominant contaminant reduction effects, recessive contaminant reduction effects, and contaminant reduction efficiency indexes. The system is used to evaluate the linkage changes in contaminant emissions reduction across different sectors, the ease of regulation, and the returns on emissions reduction efforts. The study's results demonstrate that firstly, COVID-19 initially reduced contaminant emissions across almost all sectors, although this effect waned over time. Secondly, applying conventional regulatory measures to sectors with high reductions in contaminant emissions may not yield the expected results. Thirdly, while some sectors may be more difficult to regulate, they may offer a higher return on investment in terms of emissions reduction. Based on the above results, the paper advocates for timely measures to consolidate environmental gains, prevent rebounding of contaminant emissions, prioritize supervision and management of easily regulated sectors, prioritize upgrading of cleaner production in sectors with high reduction efficiency indices, and increase investment in environmental technology. • Created a new comprehensive system for assessing contaminant emission changes. • Quantified the unique linkage changes of contaminant emissions during COVID-19. • Developed new models to reveal contaminants' regulatory difficulty and return. • The innovative reduction effects of four key contaminant indicators were measured. • Applied WHEM firstly in research across multiple areas of contaminant emissions. [ABSTRACT FROM AUTHOR]