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Cobalt is an essential material for the development of the new energy industry. Based on the latest data regarding the cobalt resource industry of China and worldwide, this study analyzes the challenges faced by the development of China’s cobalt resource industry from the aspects of cobalt resource endowment, supply-demand situation of cobalt concentrate and refined cobalt, and industry policy. China is the world’s largest producer of refined cobalt and largest consumer of cobalt; however, its cobalt resources are extremely scarce and its ultra-high dependence on foreign countries and single source of imports have put China’s cobalt resource security at risk. In response to the above problems, we propose the following countermeasures: (1) adopting effective measures to increase China’s cobalt reserves; (2) diversifying cobalt import channels to ensure a stable access to overseas cobalt resources; (3) implementing supportive policies to help China-invested overseas enterprises stabilize their production; (4) establishing a cobalt reserve system to improve the cobalt resource guarantee capacity of China; (5) strengthening the comprehensive utilization technologies to increase the amount of available cobalt resources; and (6) emphasizing research of potential cobalt resources, such as sea-floor cobalt resources in ferromanganese nodules and crusts.

Nickel resources are vital for national economic development. As the largest consumer of nickel metal worldwide, China faces a scarcity of nickel metal raw materials which depend highly on imports. Therefore, it is necessary to achieve breakthroughs in nickel resource exploration, promote the comprehensive development and utilization of nickel resources, and broaden import channels, to ensure a secure and stable supply of nickel resources. Based on the analysis of the latest data of the nickel industry, this study reviews the nickel resource endowments and the status of nickel supply and demand in China and abroad, and summarizes the genetic types, spatiotemporal distribution, and prospecting potentials of nickel ore deposits. It also analyzes the issues facing the development and supply security of China’s nickel resource industry, and proposes key technologies for nickel exploration as well as development paths for the comprehensive utilization of nickel resources. To ensure the stable supply and safe development of nickel resources in China, countermeasures are proposed from both international and domestic aspects. Internationally, it is necessary to stabilize the important nickel resource import markets represented by Indonesia and the Philippines, increase investment in mining projects overseas to enhance the international competitiveness of Chinese enterprises, and strengthen international cooperation to diversify the channels for nickel resource imports. Domestically, the following suggestions are proposed: (1) increasing nickel resource exploration, (2) promoting the comprehensive utilization of nickel resources to increase the utilization rate of recycled nickel resources, (3) optimizing traditional technical processes and adjusting the industrial structure, (4) strengthening nickel reserve bases to ensure effective increase in reserves; and (5) encouraging research on mining technologies of potential nickel ores such as ferromanganese nodules on the ocean floor.

With the popularization of transplantation technology, an increasing number of end-stage organ failure patients are undergoing transplantation surgery, and most of these patients need further monitoring and treatment in the department of critical care medicine. Due to immune suppression in transplant patients, the risk of hospital acquired infection is significantly increased. Therefore, for these patients, it is necessary to implement more stringent bundled management measures for the prevention of ventilator-associated pneumonia, catheter-related bloodstream infections, catheter-related urinary tract infections, and surgical site infections. At the same time, stricter institutional and personnel management is needed. This article, taking into account the guideline recommendations and the experience of our center, focuses on the prevention of hospital acquired infection in organ transplant patients, in order to provide reference for clinical practice of critical care medicine.

To explore the temperature distribution in width and depth of asphalt pavements with three different subgrade types, a numerical model is established. Based on actual meteorological data, the lateral temperature differences (LTDs) along the depth direction of pavement layers were analyzed under diurnal periodic thermal boundary conditions. Results reveal that the maximum LTD on the surface of a part-cut part-fill subgrade roadbed structure, as represented by a mountainous road, can reach 6.3 °C and 10.8 °C during winter and summer, respectively. The LTDs vary periodically with the boundary conditions. The LTDs on the road surface with high solar radiation in summer are 2.6–7.6 °C higher than those in winter. The influence ranges of the LTDs along the width direction of the road in winter and summer are 0–300 mm and 0–350 mm, respectively. This study provides a more precise method for studying the temperature field of road structures, which is helpful in analysing the pavement damage caused by thermal stress, etc. It also provides the necessary reference for the practical implementation of new technologies in the fields of asphalt pavement thermal energy storage systems and asphalt pavement temperature difference power generation.

The wear resistance of titanium alloy is poor, the preparation of amorphous alloy coating on the surface of titanium alloy moving parts is a choice to maintain the advantages of titanium alloy and improve its wear resistance. The microstructure and tribological behaviour of Ti-based bulk amorphous alloy before and after cryogenic-thermal cycling treatment were studied by XRD diffractometer, differential scanning calorimeter, SEM, friction and wear tester. The results show that after cryogenic-thermal cycling treatment, the titanium-based bulk amorphous alloy remains completely amorphous, and the relaxation enthalpy increases by 11%. After cryogenic-thermal cycling treatment, the average hardness of Ti-based amorphous alloy decreases from 6.84 GPa to 6.59 GPa and the average elastic modulus decreases from 118.70 GPa to 103.43 GPa, but the ratio of hardness to elastic modulus increases. The wear rate of titanium-based bulk amorphous alloy after cryogenic-thermal cycling treatment is reduced by about 10% under the load of 5 N and 10 N. Compared with TC4 alloy, the wear rate is reduced by 20% under 5 N load and 50% under 10 N load, respectively.TC4 alloy shows serious adhesive wear due to its low hardness. After cryogenic-thermal cycling treatment, the wear mechanism of titanium-based amorphous alloy is changed from abrasive wear of as-cast Ti-based amorphous alloy to the complex mechanism with abrasive, adhesive and oxidation wear. With the increase of load, adhesive wear decreases and abrasive wear is dominant.Generally, cryogenic-thermal cycling treatment is an effective way to improve the tribological properties of Ti-based bulk amorphous alloy.