When the stoichiometric proportion of Cu in Ca4 − xCuxTi4O12 polycrystalline ceramics is decreased from 3 to 2 and then to 1, the room-temperature permittivity is reduced by one order of magnitude during each step. Ca/Cu atomic disorder is observed only in some grains of Ca3CuTi4O12 single-phase polycrystalline ceramics, and the disorder is not the origin of the giant permittivity in CaCu3Ti4O12. Quantitatively, the permittivity magnitude is related to the mole ratio of polaronlike 3d electrons from Cu ions.
Since the Industrial Revolution, the productivity of human society has been qualitatively enhanced. At the same time, with the development of the social economy, the excessive pursuit of economic interests of mankind neglects the protection of ecological environment, the hole in the ozone layer, the rise of temperature, sea level rise, and other ecological problems. At the same time, the atmospheric carbon dioxide content has risen sharply, the global carbon cycle has lost its balance. The greenhouse effect is the most urgent ecological problem facing mankind. Against this background, countries have to start studying countermeasures to deal with global warming. Forest carbon sinks are important for mitigating global warming and offsetting carbon dioxide emissions. Forest carbon sink has low cost, and is easy to realize. The study of the economic value and impact of forest carbon sink factors can help provide government agencies at all levels and forestry management departments with a scientific and reasonable management basis, so as to improve the utilization rate of carbon sink and China’s voice on global climate issues. How to quantify the asset value of carbon sink resources is a hot issue today, the follows will use the relevant knowledge theory of asset assessment to discuss the characteristics of forest carbon sink resources and value composition.
The relationship between ecological environment and human’s living habitat is becoming more and more close, which provides the necessary material conditions for human’s living. The progress and development of society cannot be separated from the supply of ecological resources’ raw materials. However, because of the characteristics of ecological asset value, it is difficult to express its value directly in the form of money. Therefore, human beings often ignore part of its actual hidden value, which leads to the failure to treasure and rationally use natural resource. Man’s influence on the ecological environment is increasing day by day. Taking the Yellow River Delta as an example, this paper analyzes and evaluates the value of its ecological resource asssets, calculates the value of various ecological resource assets by using the recovery cost method, the market method, and the results reference method, and finally obtains the total value of ecological assets. In the form of concrete data, it shows the actual value of the ecosystem and improves people’s understanding of the ecological value.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.