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A bstract This paper investigates holographic torus correlators of generic operators at conformal infinity and a finite cutoff within AdS 3 gravity coupled with a free scalar field. Using a near-boundary analysis and solving the gravitational boundary value problem, we solve Einstein’s equation and calculate mixed correlators for massless and massive coupled scalar fields. The conformal Ward identity on the torus has been reproduced holographically, which can be regarded as a consistency check. Further, recurrence relations for a specific class of higher-point correlators are derived, validating AdS 3 /CFT 2 with non-trivial boundary topology. While the two-point scalar correlator is accurately computed on the thermal AdS 3 saddle, the higher-point correlators associated with scalar and stress tensor operators are explored.

A bstract In this work, we investigate holographic correlators of the stress tensor of a conformal field theory (CFT) on a torus within the context of AdS 3 / CFT 2 . To compute the correlators of the stress tensor, we employ the Einstein-Hilbert theory of gravity and perturbatively solve Einstein’s equation in the bulk. In addition, we present an explicit prescription for developing a recurrence relation that simplifies the computation of higher point correlators. Our results show that the correlators and recurrence relation are consistent with known results in CFTs. Additionally, in line with the proposed cutoff-AdS/ T T ¯ -CFT holography, we extend our computation program to investigate holographic torus correlators at a finite cutoff in the AdS 3 and derive a parallel recurrence relation associated with higher point correlators.

A bstract This work explores holographic correlators within the frameworks of two-dimensional Boundary Conformal Field Theory (BCFT) and Crosscap Conformal Field Theory (XCFT). Utilizing the AdS/CFT correspondence, we compute stress tensor correlators in BCFT, considering both tensionless and tensionful end-of-the-world (EOW) brane scenarios. We derive recurrence relations for two-point and three-point correlators and examine the impact of non-zero brane tension on correlators. Extending these results, we investigate the holographic duals of XCFTs, presenting explicit scalar and stress tensor correlator computations on projective geometries such as ℝℙ 2 . Additionally, we analyze stress tensor correlators at a finite cutoff, uncovering deformations to one-point and two-point functions induced by the cutoff. Our findings provide novel insights into the holographic structures of BCFT and XCFT while laying the groundwork for future research into higher-dimensional extensions.

A bstract In this work, we present a comprehensive study of holographic stress tensor correlators on general Riemann surfaces, extending beyond the previously well-studied torus cases to explore higher genus conformal field theories (CFTs) within the framework of the Anti-de Sitter/conformal field theory (AdS/CFT) correspondence. We develop a methodological approach to compute holographic stress tensor correlators, employing the Schottky uniformization technique to address the handlebody solutions for higher genus Riemann surfaces. Through rigorous calculations, we derive four-point stress tensor correlators, alongside recurrence relations for higher-point correlators, within the AdS 3 /CFT 2 context. Additionally, our research delves into the holography of cutoff AdS 3 spaces, offering novel insights into the lower-point correlators of the T T ¯ -deformed theories on higher genus Riemann surfaces up to the first deformation order.

Despite paramount applications of chiral trifluoromethylated compounds in medicinal chemistry and materials science, limited strategies have been developed for catalytic asymmetric synthesis of such valuable fluorinated structures. Here, we report a nickel catalyzed enantioselective dicarbofunctionalization of inexpensive industrial chemical 3,3,3-trifluoropropene (TFP) with readily available tertiary alkyl and aryl iodides. The reaction overcomes the β-F elimination side reaction of TFP, and proceeds efficiently under mild reaction conditions. The protocol possesses advantages, such as synthetic convenience, high enantioselectivity, and excellent functional group tolerance, providing rapid and straightforward access to chiral trifluoromethylated compounds of medicinal interest. Strategies for the catalytic asymmetric synthesis of trifluoromethylated compounds remain scarce. Here, the authors report the nickel-catalyzed enantioselective dicarbofunctionalization of 3,3,3-trifluoropropene.

With the advancement of industrialization, soil pollution has become a global environmental problem. In situ soil thermal remediation technology has attracted attention due to its wide application range, simultaneous removal of multiple pollutants and short time-consuming characteristics. In this study, using the principle of scale-down test, the law of temperature rise of the in situ thermal remediation of soil was experimentally studied; the heating construction period of the in situ soil remediation technology engineering application was predicted. The change law of temperature curve in different periods of soil heating is obtained. The results show that the soil temperature changes in three stages. Concentrated heating section: the temperature rises from the ambient temperature to the boiling point of water. Evaporation section: the water evaporates and the temperature maintains the boiling point temperature. Superheat section: the soil temperature continues to rise; the effect of heating power, water content and groundwater flow on heat transfer is studied. The results show that increasing the heating power, reducing the water content and preventing the seepage of surrounding water are all beneficial to the soil heating process. The research results provide favorable theoretical support for the laws of soil temperature rise, and the effect of heat transfer characteristics, simultaneously, provides a certain reference for actual soil remediation prediction, which is of great significance to the development of on-site soil thermal remediation technology.

In recent years soil contamination has become a global problem because of industrial development. In situ thermal remediation has been proposed recently to not only lower costs, but also reduce the environmental impact compared to other soil remediation technologies such as chemical remediation. During the soil thermal remediation process, factors such as soil type and water content affecting the heat transfer pose challenges. In this study, a simple mathematical model is presented and the heat transfer performance during the soil heating process is researched via COMSOL Multiphysics 5.3 software (COMSOL Inc., Stockholm, Sweden). The temperature distribution and heating period under different operating conditions are evaluated. The simulation results show that the average soil temperature exhibits three stages during the heating process. First, soil is heated from the ambient temperature to the water boiling temperature (100 °C). Then, the soil stays at the water boiling temperature for a while before reaching the target temperature. Simultaneously, the effects of initial water content and groundwater flow on heat transfer are also studied. In addition, the results of a simulation can provide a reference for in situ heating remediation technology.

The ability to maintain the microenvironment and life-support systems of an extravehicular spacesuit is an important factor in determining the duration of extravehicular activity (EVA). This paper introduces a joint human-spacesuit microenvironment dynamic model. The paper presents novel simplified human body models and analyzes expendable substances. These models can reasonably predict spacesuit safety performance, correctly respond to changes in loads, and aid in the optimization of the intensity of EVAs. According to the simulations, an 8-h EVA consumes approximately 1 kg of LiOH and 2.7 kg of water under the designed working conditions. Liquid cooling systems are the primary thermal management devices in microenvironments. Activity intensity and liquid cooling system flow rate are two important factors that influence the spacesuit microenvironment and life support material consumption. Activity intensity has a significant impact on LiOH consumption, with a threefold increase in metabolic heat increases LiOH consumption by about 2.5 times. Activity intensity plays an important role in the life-support performance of a spacesuit, and proper scheduling is critical to the efficiency and safety of EVAs. The material consumption model can estimate material consumption during the mission scheduling phase, resulting in efficient and dependable operation of the life support system.

With the development of aircraft electrification, the problem of thermal management has become increasingly prominent. It is necessary to propose a new aircraft energy management method to satisfy the needs of aircraft thermal management while maintaining high efficiency. This study addresses a compressed carbon dioxide energy storage system applied in aircraft energy management. Especially, this is the first time carbon dioxide has been used for aircraft energy storage. In this system, carbon dioxide can be used as a cold source to dissipate heat for the equipment. The system can also provide electrical energy for avionics, achieving combined cooling and power generation with a compact structure. Moreover, the energy storage unit increases the flexibility of the system. In this paper, the novel system is modeled and simulated. Results indicate that the system can operate stably to satisfy energy demand. The energy utilization efficiency of the system is 69% under design conditions. When the energy is stored first and then released, the exergy efficiency of the system can reach 81.66%, which has good economic benefits. The system is efficient, compact and flexible. It realizes the cascade utilization of energy while working, and simultaneously meets the energy requirements of cold, heat and electricity.

Curcumin, a principle bioactive component of Curcuma longa L, is well known for its anti-hyperlipidemia effect. However, no holistic metabolic information of curcumin on hyperlipidemia models has been revealed, which may provide us an insight into the underlying mechanism. In the present work, NMR and MS based metabolomics was conducted to investigate the intervention effect of curcumin on hyperlipidemia mice induced by high-fat diet (HFD) feeding for 12 weeks. The HFD induced animals were orally administered with curcumin (40, 80 mg/kg) or lovastatin (30 mg/kg, positive control) once a day during the inducing period. Serum biochemistry assay of TC, TG, LDL-c, and HDL-c was conducted and proved that treatment of curcumin or lovastatin can significantly improve the lipid profiles. Subsequently, metabolomics analysis was carried out for urine samples. Orthogonal Partial Least Squares-Discriminant analysis (OPLS-DA) was employed to investigate the anti-hyperlipidemia effect of curcumin and to detect related potential biomarkers. Totally, 35 biomarkers were identified, including 31 by NMR and nine by MS (five by both). It turned out that curcumin treatment can partially recover the metabolism disorders induced by HFD, with the following metabolic pathways involved: TCA cycle, glycolysis and gluconeogenesis, synthesis of ketone bodies and cholesterol, ketogenesis of branched chain amino acid, choline metabolism, and fatty acid metabolism. Besides, NMR and MS based metabolomics proved to be powerful tools in investigating pharmacodynamics effect of natural products and underlying mechanisms.