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With the development of the diagnosis and treatment for rare diseases and the promotion of the construction of ′Double First-Class′ Universities in China, the libraries of medical schools have to make full use of their strengths to better face new challenges in discipline construction proactively. This article refers to resource and information service practices related to the rare disease carried out by medical libraries in China and in other countries; explores the possibilities of building up the resource and information in the future, aiming at improving the awareness of rare diseases among medical students, researchers, and the general public. The article also focuses on the need for strengthening the support for teaching and research into rare diseases, hoping to contribute to the overall improvement of the diagnosis, treatment, and educational research in rare diseases in China.

The urgent need for next-generation concentrated solar power drives the pursuit of highly efficient, thermally stable, and scalable solar selective absorbing coatings (SSACs). So far, the commercially available nanocermet-based SSACs (such as Mo–SiO2, Mo–Al2O3, and W–Al2O3 coatings) suffer from optical performance degradation due to structural collapse under a high-temperature and weak oxidizing atmosphere. To address this challenge, the SiZrO dielectric and WZr–SiZrO nanocermet are developed and employed to construct SSACs. In order to obtain excellent optical performance [using the photothermal conversion efficiency (η) as the criterion], we first utilize theoretical simulations to determine the structural parameters of the target coatings. With this guidance, the WZr–SiZrO nanocermet-based SSACs are experimentally prepared, demonstrating high solar absorptance (96.8%), low emittance (14.0%@500 °C), and incident light angle insensitivity (0–56°). Benefiting from the improved thermal stability and oxidation resistance of the component materials, the prepared SSACs have enhanced high-temperature durability, maintaining η = 84.3% even after annealing at 650 °C in 0.2 Pa for 635 h. These results suggest that the well-designed WZr–SiZrO nanocermet-based SSAC is promising for use in high-temperature photothermal conversion. [ABSTRACT FROM AUTHOR]

The northern South China Sea, including the Zhujiangkou Basin and the Beibuwan Basin, developed high-quality lacustrine source rocks during the Eocene rifting period. These source rocks are vital for hydrocarbon generation in the northern South China Sea. The Zhu I depression in the Zhujiangkou Basin and the Beibuwan Basin typically exhibit high abundance of C30 4-methyl steranes. However, shales in the Eocene Wenchang Formation in the Zhu III depression of the Zhujiangkou Basin contains lower quantities of high-quality lacustrine source rocks with 4-methyl steranes, which often co-elute with some pentacyclic triterpanes in gas chromatography-mass spectrometry (GC-MS). Therefore, the single 4-methylsterane parameter based on GC-MS cannot accurately distinguish organic source in the deep to semi-deep water lacustrine source rocks of the Wenchang Formation from other source rocks, thus impeding the recognition of their contributions to petroleum reservoirs. In this study, GC-MS of aliphatic hydrocarbons, palynofacies and algal identification, as well as stable carbon isotope data of organic matter were used to identify the algal species and construct the paleoclimate during deposition of the Wenchang Formation source rocks in the Zhu III depression of the Zhujiangkou Basin. It is suggested that during the Wenchang Formation period, freshwater green algae prevailed in the lake, which is likely account for the relatively low content of 4-methyl steranes in the high-quality lacustrine source rocks. Controlled by the algal species, it is proposed that the content of C30 tetracyclic polyprenoids (TPP) can better indicate the quality of the Wenchang source rocks than C30 4-methyl steranes. Consequently, a relationship between the TPP index and the quality of the lacustrine source rocks in the Wenchang Formation of the Zhu III depression was established. A higher TPP index indicates higher organic matter abundance and hydrogen index of the lacustrine source rocks. When applied to the origin analysis of oils in the Zhu III depression, it is believed that the organic-rich deep lacustrine source rocks in the Wenchang Formation made great contribution to the transitional zone crude oils in the Wenchang A and Wenchang B depressions. [ABSTRACT FROM AUTHOR]

Continuous phase transitions exhibit richer critical phenomena on the surface than in the bulk, because distinct surface universality classes can be realized at the same bulk critical point by tuning the surface interactions. The exploration of surface critical behavior provides a window looking into higher-dimensional boundary conformal field theories. In this work, we study the surface critical behavior of a two-dimensional (2D) quantum critical Heisenberg model by tuning the surface coupling strength, and discover a direct special transition on the surface from the ordinary phase into an extraordinary phase. The extraordinary phase has a long-range antiferromagnetic order on the surface, in sharp contrast to the logarithmic decaying spin correlations in the 3D classical O(3) model. The special transition point has a new set of critical exponents, $y_{s}=0.86(4)$ and $\eta_{\parallel}=-0.33(1)$, which are distinct from the special transition of the classical O(3) model and indicate a new surface universality class of the 3D O(3) Wilson-Fisher theory.

In liquid hydrogen (LH2) delivery, submersible centrifugal pump is an important device. Its reliability and efficiency rely on the stability of the bearings. In a high‐speed range, cavitation occurs due to the hydrodynamic effect induced pressure undulation. Compared with other cryogenic fluids, cavitation in LH2 is prone to happen due to its special properties. In this paper, a cavitation model considering thermal properties of LH2 is proposed based on Rayleigh–Plesset equation. Cavitation characteristics are studied in spiral grooved thrust bearing (SGTB) lubricated by LH2. The effect of cavitation on load capacity and friction torque are investigated. The most severely‐eroded location is predicted by the distribution of mass transfer rate. The influence of bearing structure parameters is studied in respect of cavitation, load capacity and friction torque. The analysis of variance (ANOVA) and range analysis results may provide a reference for optimising LH2 lubricated SGTB. [ABSTRACT FROM AUTHOR]