Core Viewpoint - The article discusses the VAT policy for resource comprehensive utilization, specifically the immediate refund of VAT for general taxpayers selling self-produced resource utilization products and providing related services [3][4]. Group 1: Policy Overview - The VAT immediate refund policy aims to promote the sustainable development of the resource comprehensive utilization industry [3]. - Eligible entities include general taxpayers who sell self-produced resource utilization products and provide related services [4]. Group 2: Eligibility Criteria - Taxpayers must obtain VAT invoices from sellers for recycled resources purchased domestically, and if applicable, must acquire regular VAT invoices [5]. - A record-keeping system for recycled resource purchases must be established by the taxpayer [5]. - The products and services sold must not fall under the categories of eliminated or restricted projects as per the National Development and Reform Commission's guidelines [5]. - The products and services must not be classified as "high pollution, high environmental risk" by the Ministry of Ecology and Environment [5]. - If the utilized resources are classified as hazardous waste, a permit from the provincial or municipal ecological environment department is required [5]. - Taxpayers must not have a tax credit rating of C or D [5]. - Taxpayers must not have violated environmental protection laws or tax regulations in the six months prior to applying for the refund [6]. Group 3: Example Calculation - An example illustrates that if a company meets the criteria, it can apply for a VAT refund based on its sales and input tax amounts. For instance, if the sales amount is 10 million yuan with an output tax of 1.3 million yuan and an input tax of 400,000 yuan, the refundable amount would be calculated as (1,300,000 - 400,000) × 70% = 630,000 yuan [8].

Core Viewpoint - The innovative technology for high-value recycling of waste concrete developed by Nanjing University of Technology addresses the challenge of achieving carbon neutrality by enhancing the performance of recycled concrete materials in structural engineering [1][2]. Group 1: Technological Innovations - The research team led by Associate Professor Xu Jinjun has created an automated washing and screening equipment for recycled aggregates, significantly improving the physical properties of recycled coarse aggregates [1]. - The new pre-treatment process for recycled fine aggregates involves a combination of calcium hydroxide soaking and carbon dioxide curing, resulting in an increase in apparent density by 1.8% to 4.8% and a reduction in crushing rate by 20.2% to 23.5% compared to traditional methods [1]. Group 2: Performance Optimization - The team has optimized the mix design of recycled concrete to address the challenges of achieving the right consistency, utilizing methods such as the equivalent mortar volume method and the equivalent total water method to enhance mechanical strength while reducing water usage [1][2]. - A database has been established to record the performance of recycled concrete under various environmental conditions, allowing for precise calculations of the optimal mix ratios of cement, water, sand, and recycled aggregates [2]. Group 3: Structural Enhancements - The team has innovatively integrated internal steel and external steel casing into the structure of recycled concrete, enhancing its stability and safety [2].