Ramp facies in an intracratonic basin: A case study from the Upper Devonian and Lower Carboniferous in central Hunan, southern China

AbstractDetailed studies on Late Devonian to Early Carboniferous carbonate rocks in central Hunan, southern China have led to the recognition of 25 lithofacies which can be grouped into: (1) inner ramp peritidal platform, (2) inner ramp organic bank and mound, (3) mid ramp, (4) outer ramp, and (5) shelf basin facies associations. The peritidal platform facies association dominates the Zimenqiao Formation (Namurian A or late Datangian) and is characterized by gypsum and dolostone-containing sequences, indicating a peritidal platform environment. The other four facies associations dominate the Menggongao Formation (late Famennian), Liujiatang Formation (Tournaisian or Yangruanian), Shidengzi Formations (early Visean or early Datangian). Five upward-shallowing cycles were distinguished in these three Formations. The predominant facies associations developed in each Formation demonstrate an overall transgression–regression cycle in the Late Devonian to Early Carboniferous in central Hunan. The overall transgressive sequence was preserved in the Shaodong, Menggongao, and Liujiatang Formations, and the overall regressive sequence was preserved in the Liujiatang, Shidengzi, Ceshui and Zimenqiao Formations

Retinexformer: One-stage Retinex-based Transformer for Low-light Image Enhancement

When enhancing low-light images, many deep learning algorithms are based on the Retinex theory. However, the Retinex model does not consider the corruptions hidden in the dark or introduced by the light-up process. Besides, these methods usually require a tedious multi-stage training pipeline and rely on convolutional neural networks, showing limitations in capturing long-range dependencies. In this paper, we formulate a simple yet principled One-stage Retinex-based Framework (ORF). ORF first estimates the illumination information to light up the low-light image and then restores the corruption to produce the enhanced image. We design an Illumination-Guided Transformer (IGT) that utilizes illumination representations to direct the modeling of non-local interactions of regions with different lighting conditions. By plugging IGT into ORF, we obtain our algorithm, Retinexformer. Comprehensive quantitative and qualitative experiments demonstrate that our Retinexformer significantly outperforms state-of-the-art methods on thirteen benchmarks. The user study and application on low-light object detection also reveal the latent practical values of our method. Code, models, and results are available at https://github.com/caiyuanhao1998/RetinexformerComment: ICCV 2023; The first Transformer-based method for low-light image enhancemen

Femtosecond laser-heating effect on the magnetization dynamics in perpendicularly magnetized Ta/CoFeB/MgO film

We have studied the effect of ultrafast laser-heating on the magnetization dynamics of perpendicularly magnetized CoFeB film by means of the time-resolved magneto-optical Kerr rotation effect. The effective perpendicular magnetic anisotropy field HK is significantly decreased with enhancing the pump laser-fluence in a moderate range of 5-12 mJ cm-2. The Gilbert damping, however, is found to be independent of the pump fluence. These findings provide a new method of separately manipulating the Gilbert damping and perpendicular magnetic anisotropy

Entrepreneurial founder's social ties, institutions, and firm's productivity: Evidences from China's newly listed firms

Social ties, as informal institutions, contribute to firms' performance in emerging economies. Formal market-supporting institutions in emerging economies are in general less developed, social ties cultivated by entrepreneurs thus serve as substitutes for formal institutional support. However, the role of social ties as informal institutions and interactions between social ties and market-supporting institutions are yet to be fully explored. Using the sample of 428 newly listed firms on the Growth Enterprise Market of Shenzhen Stock Exchange of China between 2009 and 2016, this paper examines the interplays among the entrepreneurial founder's political ties and managerial ties, marketization, and firm's productivity, measured by firm-level total factor productivity. Our findings indicate that the entrepreneurial founder's managerial ties enhance firm productivity whilst political ties reduce productivity. We also find that marketization positively moderates the effects of the entrepreneurial founder's political and managerial ties on productivity. Our findings demonstrate the strategic importance of the informal institutions and contribute to an improved understanding of the complementary effects between social ties and marketization in an important emerging economy

12-Nitro­methyl-14-deoxy­andro­graph­olide

In the mol­ecule of the title compound {systematic name: 3-[2-(6-hydr­oxy-5-hydroxy­methyl-5,8a-dimethyl-2-methyl­ene­per­hydro-1-napth­yl)-1-(nitro­meth­yl)eth­yl]-2(4H)-furan­one}, C21H31NO6, the cyclo­hexane rings have chair conformations. Intra­molecular O—H⋯O hydrogen bonding results in the formation of a six-membered non-planar ring with a twist conformation. In the crystal structure, inter­molecular O—H⋯O hydrogen bonds link the mol­ecules into infinite chains along the c axis

Multi-functional anodes boost the transient power and durability of proton exchange membrane fuel cells.

Proton exchange membrane fuel cells have been regarded as the most promising candidate for fuel cell vehicles and tools. Their broader adaption, however, has been impeded by cost and lifetime. By integrating a thin layer of tungsten oxide within the anode, which serves as a rapid-response hydrogen reservoir, oxygen scavenger, sensor for power demand, and regulator for hydrogen-disassociation reaction, we herein report proton exchange membrane fuel cells with significantly enhanced power performance for transient operation and low humidified conditions, as well as improved durability against adverse operating conditions. Meanwhile, the enhanced power performance minimizes the use of auxiliary energy-storage systems and reduces costs. Scale fabrication of such devices can be readily achieved based on the current fabrication techniques with negligible extra expense. This work provides proton exchange membrane fuel cells with enhanced power performance, improved durability, prolonged lifetime, and reduced cost for automotive and other applications