With the increasing demand for sustainable energy, advanced characterization methods are becoming more and more important in the field of energy materials research. With the help of X-ray imaging technology, we can obtain the morphology, structure and stress change information of energy materials in real time from two-dimensional and three-dimensional perspectives. In addition, with the help of high penetration X-ray and high brightness synchrotron radiation source, in-situ experiments are designed to obtain the qualitative and quantitative change information of samples during the charge and discharge process. In this paper, X-ray imaging technology based on synchrotron and its related applications are reviewed. The applications of several main X-ray imaging technologies in the field of energy materials, including X-ray projection imaging, transmission X-ray microscopy, scanning transmission X-ray microscopy, X-ray fluorescence microscopy and coherent diffraction imaging, are discussed. The application prospects and development directions of X-ray imaging in the future are prospected.

China’s economic structure has made subtle changes with the development of digital economy. Along with the marginal diminishing effect of Chinese monetary policies and the increase of the overall leverage ratio, the Chinese economic growth mode of relying on real estate, trade and infrastructure construction in the past will not be sustainable in the next decade. This paper makes a theoretical analysis on the reduction of the search cost in digital economy. Also, this paper used empirical methods to study the relationship between China’s economic growth and digital infrastructure construction. In conclusion, the digital economy has reduced the search cost for people, and big data will become a product factor participating in labor distribution. In addition, this paper proposes for the first time that digital economy can effectively restrain inflation. The Chinese government needs to attach importance to the issue that current internet enterprise oligarchs will probably monopolize the usage of big data in the development of digital economy in the future and become the obstacle to effective economic growth. In addition, close attention should be paid to the vulnerabilities of financial and taxation systems for digital economic entities to avoid continuous disguised tax subsidies to internet oligarchs, thus preventing industrial monopoly.

Using a newly-developed data set for Portugal, we analyze the industry-level effects of infrastructure investment. Focusing on the divide between traded and non-traded industries, we find that infrastructure investments have a non-traded bias, as these shift the industry mix towards private and public services. We also find that the industries that benefit the most in relative terms are all non-traded: construction, trade, and real estate, among the private services, and education and health, among the public services. Similarly, emerging trading sectors, such as hospitality and professional services, stand to gain. The positive impacts on traded industries are too small to make a difference. These results highlight that infrastructure-based strategies are not neutral in terms of the industry mix. Moreover, with most of the benefits accruing to non-traded industries, such a development model that is heavily based on domestic demand may be unsustainable in light of Portugal’s current foreign account position. 

BiVO₄ was hydrothermally synthesized under different preparing conditions and characterized by XRD, SEM, Raman spectrum and BET specific surface area. The influence of different pH value and annealing temperature and hydrothermal time on the morphologies and structures of the BiVO₄ samples was investigated systematically. It can be found that annealing would eliminate the effects caused by the pH of precursor, heating temperature and heating time, but preparing conditions still influenced the size and specific surface area of samples. Furthermore, the photocatalytic activities of the fabricated BiVO₄ were also evaluated by the degradation of methyl blue in aqueous solution under UV and visible light irradiation.

Helical deep hole drilling is a process frequently used in industrial applications to produce bores with a large length to diameter ratio. For better cooling and lubrication, the deep drilling oil is fed directly into the bore hole via two internal cooling channels. Due to the inaccessibility of the cutting area, experimental investigations that provide information on the actual machining and cooling behavior are difficult to carry out. In this paper, the distribution of the deep drilling oil is investigated both experimentally and simulatively and the results are evaluated. For the Computational Fluid Dynamics (CFD) simulation, two different turbulence models, i.e. the RANS k-ω-SST and hybrid SAS-SST model, are used and compared. Thereby, the actual used deep drilling oil is modelled instead of using fluid dynamic parameters of water, as is often the case. With the hybrid SAS-SST model, the flow could be analyzed much better than with the RANS k-ω-SST model and thus the processes that take place during helical deep drilling could be  simulated with realistic details. Both the experimental and the simulative results show that the deep drilling oil movement is almost exclusively generated by the tool rotation. At the tool’s cutting edges and in the flute, the flow velocity drops to zero for the most part, so that no efficient cooling and lubrication could take place there. In addition, cavitation bubbles form and implode, concluding in the assumption that the process heat is not adequately dissipated and the removal of chips is adversely affected, which in turn can affect the service life of the tool and the bore quality. The carried out investigations show that the application of CFD simulation is an important research instrument in machining technology and that there is still great potential in the area of tool and process optimization.