MXene Hollow Spheres Supported by a C–Co Exoskeleton Grow MWCNTs for Efficient Microwave Absorption

High-performance microwave absorption(MA) materials must be studied immediately since electromagnetic pollution has become a problem that cannot be disregarded. A straightforward composite material, comprising hollow MXene spheres loaded with C–Co frameworks, was prepared to develop multiwalled carbon nanotubes(MWCNTs). A high impedance and suitable morphology were guaranteed by the C–Co exoskeleton, the attenuation ability was provided by the MWCNTs endoskeleton, and the material performance was greatly enhanced by the layered core–shell structure. When the thickness was only 2.04 mm, the effective absorption bandwidth was 5.67 GHz, and the minimum reflection loss(RLmin) was-70.70 d B. At a thickness of 1.861 mm, the sample calcined at 700 ℃ had a RLmin of-63.25 d B. All samples performed well with a reduced filler ratio of 15 wt%. This paper provides a method for making lightweight core–shell composite MA materials with magnetoelectric synergy.

Strategies for Construction of Majors in Universities with Different Characteristic Based on Social Needs

We used the basic principles of game theory to investigate development strategies for standards of professional competence in universities in the same geographic area,under conditions of non-uniform distribution of social demand preference.The results revealed that,under various conditions in our model,different approaches for differential strategies were selected by university U2 compared with university U1.Specifically,in the competition between U1 and U2,there is a differential strategy compression point of U2 to U1;When U2 universities choose the biggest differentiation strategy,university U1 also have differentiated strategy control points.Arbitrary decision-making of university U1 in relation to university U2 was based on the requirements of professional competence standards,according to the change of the social demand for professional competency standard,universities U2 will adopt the strategy of"no difference","maximum differentiation"and"comprehensive intermediate strategy",respectively.The current results have theoretical implications for the selection of professional development and professional competence development strategies in asymmetric universities operating in the same geographic area.

Analysis of Green Technology Upgrading Strategy Based on Collaborative Incentive of Environmental Policy and Green Finance

With the continuous development of economy, the bottleneck problem of environmental resources has become increasingly prominent. Enterprise environmental governance technology innovation incentive has become an important issue for the development of government, society and enterprises. Under the control of enterprise's expected economic target, this paper discusses the synergistic incentive effect of environmental policy and green finance on enterprise's environmental governance technology innovation decision by using nonlinear programming model. The results show that when the funds for environmental governance technological innovation are insufficient, there is an optimal decision space to use green financial loans to implement technological innovation and upgrade, and then achieve the expected economic goals;Under a given level of environmental governance technology, environmental policies affect whether enterprises can make decisions on technological innovation and upgrading of environmental governance;Green financial mechanism will not. However, when the enterprise makes the decision of environmental governance technology upgrading, it will affect the enterprise's decision on green financial loan amount. The results of the study have guiding significance for the formulation of environmental policy and green financial policy, as well as the decision-making of enterprise environmental governance technology innovation and upgrading.