Encapsulation and thermal properties of composite phase change materials based on cobalt/nitrogen double-doped ZIF-67 derived carbon.

To solve the problems of easy leakage and weak thermal conductivity of single-phase change material, in this experiment, cobalt/nitrogen-doped ZIF-67 derived carbon (CoN-ZIF-Cx) was constructed as the carrier material, and paraffin was used as the phase change core material to construct thermally enhanced shaped composite phase change materials (P0.6@CoN-ZIF-Cx). The composite PCMs were characterized using scanning electron microscopy, isothermal nitrogen adsorption-desorption, X-ray diffraction, and Fourier infrared spectroscopy, and their performance was evaluated using transient planar heat source techniques, differential scanning calorimetry, and thermal cycling tests. The results indicated that the impurities of the acid-washed porous carbon material were reduced and the loading of the paraffin was 60%, and the prepared P0.6@CoN-ZIF-Cx had an excellent thermal performance. Among them, P0.6@CoN-ZIF-C3 has the melting and crystallization enthalpy of 71.03 J g-1 and 68.81 J g-1. The thermal conductivity is 0.4127 W m-1 K-1, a 46.19% thermal conductivity improvement compared with pure paraffin. It still has favourable thermal storage capacity after 50 cycles without paraffin leakage during the phase transition.

China's green data center development:Policies and carbon reduction technology path.

Data center is a very important infrastructure to support the development of information technology, and its development and increment are very remarkable. However, with the rapid and large-scale development of data centers, the problem of energy consumption turns to be also very prominent. Under the background of global carbon peak and carbon neutrality, developing green and low-carbon data centers has become an inevitable trend. This paper reviews and analyzes the policies and their roles in promoting China's green development of data centers in the past 10 years, summarizes the current situation of the implementation of green data center projects in China and gives the changes of PUE limits of data centers under the policy constraints. Application of green technologies is an important measure for energy-saving and low-carbon development of data centers, so encouraging innovation and application of green technologies in data center is also a priority task in relevant policies. This paper points out the green and low-carbon technology system of data centers, further summarizes energy-saving and carbon-reducing technologies in IT equipment, cooling system, power supply and distribution system, lighting, intelligent operation and maintenance, and provides an outlook on the future green development of data centers.