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Managing the stability of today's electric power systems is based on decades of experience with the physical properties and control responses of large synchronous generators. Today's electric power systems are rapidly transitioning toward having an increasing proportion of generation from nontraditional sources, such as wind and solar (among others), as well as energy storage devices, such as batteries. In addition to the variable nature of many renewable generation sources (because of the weather-driven nature of their fuel supply), these newer sources vary in size - from residential-scale rooftop systems to utility-scale power plants - and they are interconnected throughout the electric grid, both from within the distribution system and directly to the high-voltage transmission system. Most important for our purposes, many of these new resources are connected to the power system through power electronic inverters. Collectively, we refer to these sources as inverter-based resources.

Natural graphite is a new-technology mineral resource led by new mineral preparation and application technologies and an important raw material that supports the development of China’s strategic emerging industries. This paper analyzes the demand for high-quality development of graphite resources and the graphite material industry, summarizes the development status, unveiled development potentials and major challenges, and puts forward goals for next stage development. Furthermore, this paper proposes the following measures: (1) establishing a technology innovation system that focuses on the deep processing of graphite; (2) optimizing the allocation of resources and boosting the development of green graphite plants and mines; (3) strengthening the capacities of platforms to consolidate the technological innovation foundation for industrial and supply chains; and (4) focusing on breakthroughs in the xclusive application of graphene’s uniqu physical properties and avoiding excessive marketing. Additionally, it is necessary to set up a sophisticate database that covers the entire industrial and supply chains of graphite, establish a long-term policy mechanism that supports the high-quality development of China’s graphite industry, accelerate resource integration to construct an international graphite valley, and improve innovation platforms to enhance talent trainning.

Many major diseases can cause changes in the morphology of blood vessels, and the segmentation of retinal blood vessels is of great significance for preventing these diseases. Obtaining complete, continuous, and high-resolution segmentation results is very challenging due to the diverse structures of retinal tissues, the complex spatial structures of blood vessels, and the presence of many small ships. In recent years, deep learning networks like UNet have been widely used in medical image processing. However, the continuous down-sampling operations in UNet can result in the loss of a significant amount of information. Although skip connections between the encoder and decoder can help address this issue, the encoder features still contain a large amount of irrelevant information that cannot be efficiently utilized by the decoder. To alleviate the irrelevant information, this paper proposes a feature selection module between the decoder and encoder that utilizes the self-attention mechanism of transformers to accurately and efficiently select the relevant encoder features for the decoder. Additionally, a lightweight Residual Global Context module is proposed to obtain dense global contextual information and establish dependencies between pixels, which can effectively preserve vascular details and segment small vessels accurately and continuously. Experimental results on three publicly available color fundus image datasets (DRIVE, CHASE, and STARE) demonstrate that the proposed algorithm outperforms existing methods in terms of both performance metrics and visual quality. [ABSTRACT FROM AUTHOR]

BACKGROUND: Polymeric microcapsules (MCs) have become an important issue and have attracted increasing attention because of their tunable physical and chemical properties. Diverse shell structures can confer multiple properties on MCs. RESULTS: Different polyols (1,4‐butanediol and glycerin) and polyamines (triethylenetetramine and isophorondiamine) were selected as crosslinkers to obtain emamectin benzoate (EB)‐loaded poly(urethane–urea) MCs (PU‐MCs) by interfacial polymerization. The four obtained PU‐MCs showed sphericity with different degrees of smoothness on their surfaces, and displayed a uniform size distribution ranging from 500 to 700 nm. Moreover, transmission electron microscopy showed that the shell thickness was roughly uniform, and was greatly influenced by the type and structure of the crosslinker. GI‐MCs, prepared using glycerin and isophorondiamine, had the largest shell thickness. GT‐MCs, obtained using glycerin and triethylenetetramine, had the highest encapsulation efficiency and drug‐loading content, and BT‐MCs, obtained using mixtures of 1,4‐butanediol and triethylenetetramine, had the fastest release behavior. Thermogravimetric analysis revealed that the greater the degree of shell crosslinking, the higher decomposition temperature and the greater the thermal stability. A BT‐MC suspension had the lowest viscosity and contact angle with the best wettability. Bioassay experiments showed that BT‐MCs exhibited good insecticidal activity against Plutella xylostella larvae with a half‐maximal lethal concentration of 4.19 mg/L. Furthermore, a BT‐MC suspension showed good thermal and light stability, with potential applications in minimizing the toxicity of EB through sustained release. CONCLUSION: Various properties of EB‐loaded PU‐MCs were modulated through simple selection of different polyols and polyamines during fabrication, which might have an important role in constructing the pesticide delivery system and improving pesticide utilization. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

For engineering waste soils with a large proportion of sand resources, an effective technique for sand extraction from waste soils still needs to be developed. This study investigates the degree and efficiency of sand resource extraction based on a hydro-cyclone separation principle via a series of experiments. The soil samples in the experiments contained a sand content ranging from 12.56% to 52.75% and a water content ranging from 155.96% to 597.04%. The results show that the water contents of test samples should reach a certain threshold to perform hydro-cyclone separation, and appropriately increasing the water content will have a positive effect on the separation degree, which can achieve a maximum value of 73.26%. However, the separation degree reaches an upper limit value when the water content is greater than approximately 400%, which is revealed by the characteristics of soil viscosity varying with water content, and high-water content for the separation efficiency is not beneficial. To balance the separation degree and efficiency, optimum sample water contents for sand extraction and an evaluation approach for different sand content samples are proposed. Through application of the proposed approach, an average sand extraction efficiency of 135.88 g/s can be achieved. [ABSTRACT FROM AUTHOR]