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Division 5 of the ASME code section Ⅲ (referred to as ASME-Ⅲ-5) provides design-by-analysis methods and evaluation criteria for Class 1 nuclear components working at high temperatures. It has a long history and is the main international design code for high temperature nuclear equipment. It took the lead in adopting the idea of stress classification and first introduced the concepts of primary stress, secondary stress and peak stress, which had a far-reaching impact on the development of subsequent other high temperature design codes. However, with the rapid development of computational methods, high-performance computer technology, commercial finite element software and high temperature inelastic analysis methods, the results derived from elastic analysis and the evaluation of stress classification used by ASME as a mainstream method exist the limitation of overly conservatism and thus insufficient design economy. This paper first introduced the definition of high temperature condition and the insignificant creep temperature, as well as the design loads, failure mechanisms, design-by-analysis methods, and evaluation criteria of ASME code for nuclear Class 1 components at high temperature. Then, by comparing the analysis methods and criteria of primary load limit and deformation control limit of ASME with other high temperature codes, such as R5, RCC-MRx and MONJU (with or without consideration of the time dependence of creep), the advantages and limitations of ASME analysis methods and criteria were explored. Each code has its distinct characteristic. British R5 code focuses on the reference stress method and the application of limit analysis. French RCC-MRx code is in the same lineage with ASME, but distinguishes between significant/insignificant creep and significant/insignificant irradiation effects. Japanese MONJU code distinguishes the long-term load from short-term load, such as seismic load. Long-term loads and short-term loads adopt different limits to avoid overly conservatism. It is concluded that the elastic analysis based on the stress classification traditionally adopted by the ASME code is excellent, but it cannot perfectly cope with the all the code-considered failure mechanisms due to its inherent characteristics. Therefore, several methods are proposed as alternative methods for the ASME-Ⅲ-5 improvement. The pointed-out directing improvement aspects of ASME-Ⅲ-5 enable to enhance the advancement, economy and safety of the development and use of ASME, with the scientific integration of the traditional design of pressure vessels and the new era of computational analysis technology. At the same time, this study also has important guiding value for the development and construction of Chinese independent design code in nuclear Class 1 high temperature pressure-bearing components.

We propose and demonstrate a chiral metasurface with capability for high Q-factor, near-unity (0.999) circular dichroism (CD) via utilization of bound states in the continuum. The CD response can be reversed with the value ranging from −0.7 to 0.82 by increasing structural perturbations to induce chiral magnetic quadrupole modes and the accompanied phase jump. In addition, more than 100-fold enhancement of C/CCPL in the superchiral near field is achieved while maintaining a high Q-factor of 105. The findings hold broad application prospects in chiral sensing, valley electronics, and ultrasensitive chiral spectroscopy detection. [ABSTRACT FROM AUTHOR]

The advancements in chiroptics have propelled applications beyond traditional optics, expanding its reach into domains such as heat and fluid mechanics. The current research predominantly focused on utilizing plasmonic materials in the photothermal and photofluidic systems. However, these systems face limitations in circular dichroism due to inherent Ohmic loss associated with plasmonic materials. Herein, we introduce the concept of topological polarization singularity in an all-dielectric structure, which supports chiral bound states in the continuum. The introduction of topological polarization singularity gives the structure an impressive chiral light absorption response. The BICs resonant mode achieves a 147-fold field enhancement, significantly improving the photothermal conversion efficiency of dielectric material. Moreover, the g factors of photothermal and optical fluids reach 1.9, approaching the theoretical limit value. Consequently, an exceptionally high degree of circular dichroism is realized in multiple systems including light absorption, photothermal, and photofluidic systems. Our proposed structures can potentially be used in chiral photothermal and chiral nanoparticle capture, as well as photofluidic applications related to biochemistry and clinical biology. [ABSTRACT FROM AUTHOR]

Due to its significant physiological effects, a sulfated polysaccharide has been considered an important nutrient of sea cucumber, but its metabolism in vivo is still unclear. The present study investigated the metabolism of a sea cucumber sulfated polysaccharide (SCSP) in rats and its influence on the metabolite profiles. The quantification by HPLC-MS/MS revealed that the blood level of SCSP achieved a maximum of 54.0 ± 4.8 μg/mL at 2 h after gavage, almost no SCSP was excreted through urine, and 55.4 ± 29.8% of SCSP was eliminated through feces within 24 h. These results prove the utilization of SCSP by gut microbiota, and a further microbiota sequencing analysis indicated that the SCSP utilization in the gut was positively correlated with Muribaculaceae and Clostridia_UCG-014. In addition, the non-targeted metabolomic analysis demonstrated the significant effects of SCSP administration on the metabolite profiles of blood, urine, and feces. It is worth noting that the SCSP supplement decreased palmitic acid, stearic acid, and oleic acid in blood and urine while increasing stearic acid, linoleic acid, and γ-linolenic acid in feces, suggesting the inhibition of fat absorption and the enhancement of fat excretion by SCSP, respectively. The present study shed light on the metabolism in vivo and the influence on the fat metabolism of SCSP. [ABSTRACT FROM AUTHOR]

We present a feasible way to strongly enhance Raman signals via introducing an ultra-thin dielectric film in the dual-layer plasmonic hotspots structure, which forms a quasi-three-dimensional structure. The Raman intensity was obtained with an enhancement factor of 735% for the dual-layer metal structure buffered with an ultra-thin silicon film. Moreover, the silicon layer based surface-enhanced Raman scattering (SERS) substrate provided a Raman signal two to five times larger than that of the silica buffered substrate. These distinct responses confirm that the ultra-thin high-index semiconductor film has the capability of additionally enhancing Raman scattering. Otherwise, the upper and lower metal clusters can support multiple kinds of plasmonic resonances, which produce a remarkable physical enhancement of the Raman signals. Besides these impressive optical properties, the substrates have prominent advantages on structural features, since the fabrication process can be fulfilled simply, suggesting a feasible way for a large-area and low-cost SERS platform. The findings may pave an avenue to achieve insights on the dielectric enhanced Raman scattering and hold potential applications in optoelectronics, such as environmental and health sensors.

In this work, we propose a titanium nitride (TiN)-based ultra-broadband perfect absorber from the ultraviolet to near-infrared wavelength ranges with the average absorptivity up to 96.7%. The weighted absorption efficiency of the solar radiation energy reaches 95.6%. In addition, photothermal therapy is conducted on such absorber, showing the effectively confined local high-temperature in the vicinity of the device. The steady-state temperature reaches 327 K at a depth of 3 mm beneath the tissue surface, leading to the efficient optical damage exceeding 90% for the surrounding diseased tissue only by a 3-min illumination. Such moderate photothermal therapy adequately meets the requirements for inactivating tumor cells and hold wide applications in the photo-biomedical science and technology. [ABSTRACT FROM AUTHOR]

In this study, a Gracilaria lemaneiformis slurry (GLS) was prepared using low-energy mechanical shearing. The resulting GLS, which was rich in polysaccharides, was utilized as an effective stabilizer for oil-in-water emulsions. The microstructures and stability of the resulting emulsions were controlled by adjusting the emulsion formulations, including Gracilaria lemaneiformis (GL) mass concentration and oil volume fraction (φ). The optimized GL mass concentration and φ conditions yielded high internal phase emulsions (HIPEs) with gel-like textures. Moreover, the presence of exogenous Ca2+ resulted in bridging structures in the emulsions, enhancing their viscoelasticity and forming a robust physical barrier against droplet coalescence. Our findings highlight the effectiveness of the GLS as an emulsifier for stabilizing HIPEs. Notably, this method relies solely on physical processes, aligning with the desirability of avoiding chemical additives, particularly in the food industry. [ABSTRACT FROM AUTHOR]