清水气举反循环钻探工艺在深水井施工中的应用

清水气举反循环钻探工艺是解决含水层裂隙在钻探过程中被堵塞问题的一种有效方法，尤其是对层压较低、裂隙稀少的含少层段，含水裂隙一旦发生堵塞则不易清洗干净，严重影响水井出水量，甚至造成水井报废。该方法的引入，对提高北京地热井水量有积极作用。     

世界高科技园区建设和发展的趋势

本文在资料分析和历史回顾的基础上，论述了世界高科技园区的发展趋势。     

中国国家自然地图集电子版的设计和研制

本文阐述中国国家自然地图集电子版的设计与研制过程中的若干理论、方法、技术问题及实例。文章首先分析了研制中国国家自然地图集电子版的背景和科研、政府部门、大众等用户对它的需求,以及中国科学院知识创新工程对它的项目和经费支持。其次,文章阐述了该电子版的设计原则和若干理论、方法问题,包括在内容上的再创作,在技术上的创新,在功能上的突破,以及在屏幕界面感知效果上的要求和原则。再次,本文介绍了本电子版的体系结构和关键技术。其中体系结构和技术系统包括数据、软件、辅助资料、模型与方法,以及它的四方面的功能,即图集阅览功能、表达—模拟功能、查询—检索功能、量测分析功能。关键技术则涉及到开发平台的选择、三维和动态数据模型的建立、多源多类数据的集成３个方面。第四,文章分析了中国国家自然地图集电子版的主要特色,包括独特的交互界面结构、别致的动态交互工具、各种形式的动态地图、丰富的三维地图浏览、生动形象的三维地形虚拟飞行、新颖的多种表达方法的联合、适当的分析和查询功能。最后,文章阐明了该电子版的未来发展方向和版本更新计划。     

三维扫描仪协同GNSS-RTK在复杂地形测量中的应用研究

建设工程进行过程中施工现场地形复杂且呈现动态变化,施工过程中工程实体形度和施工操作对周围环境造成的影响都需要进行监控测量,建设工程施工测量是复杂地形测量的代表。本文讨论复杂地形监控测量过程中利用三维激光扫描测量的快速获取数据,获取到的据利用专业的处理软件处理后获得监控测量物体的立体成像结果,再利用全球导航卫星系统实时动态载波相位差分技术(GNSS-RTK)辅助测量监控点的空间坐标变化以及高程差。两者协同应用可以既快速又准确的进行复杂地形的监控测量。     

非开挖技术在矿难事故中的可能应用

时至今日中国的改革开放已经取得了举世瞩目的成就,现代化建设日益欣欣向荣。但是近年来煤矿行业不断地发生重大恶性事故,伤亡严重,给社会带来了极大的负面影响。因而,矿难后的援救工作更是在整个矿难事故中起着关键的作用,很多时候因为救援工作方法的不当,时间的不及时而最终酿成重大的安全事故。因此,本文主要介绍结合红外探测技术的非开挖技术在处理矿难事故中的可能应用,旨在阐述该技术的可行性。     

非开挖水平定向钻机钻头的类型及适应性分析

非开挖水平钻机是非开挖铺管技术的核心机械,直接关系到铺设工程的成败;钻头作为钻机的一个部件,主要起到导向成孔、扩孔和清孔的作用。钻头的选择直接关系到后续拖管的难易程度,因此,根据不同的地质和施工要求应选择相应的钻头。本文就非开挖钻机扩孔钻头的类型及适应性作了详细地分析。     

Understanding the latest progress in mitigating climate change and facilitating carbon neutrality北大核心CSCD

The Intergovernmental Panel on Climate Change (IPCC) released the report of Working Group III of the Sixth Assessment Report "climate change 2022: mitigating climate change". The report accessed and summarized the latest research progress on climate change mitigation since the release of the Fifth Assessment Report, which will provide an important reference for the international community to further understand climate change mitigation actions, system transformation, and the pursuit of sustainable development. The report pointed out that human activities had cumulatively emitted about 2.4 trillion tons of CO2 from 1850 to 2019, of which 58% was emitted before 1990. In order to control the level of global temperature rise in the future, deep and immediate mitigation actions are required. In both low and minimum emission scenarios, fossil energy needs to be greatly reduced; renewable energy will be the mainstay of future energy supply; achieving carbon neutrality requires relying on negative emission technologies and increasing carbon sinks. Technological progress is one of the key conditions for helping the world combat climate change. Accelerated and equitable climate action is critical to sustainable development. The report's conclusions once again show that China's carbon neutrality target is in line with the mitigation path of the Paris Agreement's temperature rise target of less than 2 °C and striving to achieve 1.5°C. In the future, China should strengthen special research programs on the national concerns and key contents covered in the report. While strengthening scientific interpretation and effective use of the report's conclusions, it is also necessary to actively participate in the IPCC scientific assessment process, actively contribute Chinese wisdom, and contribute to the international dissemination of Chinese climate governance concepts. © 2022 Chinese Journal of Digestive Endoscopy All rights reserved.     

China’s pathway to carbon neutrality for the iron and steel industry

As a hard-to-abate sector, the iron and steel industry is responsible for 22% of China’s total carbon emissions and therefore plays a crucial role in achieving China’s carbon peaking and neutrality target. Nearly 90% of China’s iron and steel output is produced with coal-based blast furnaces, which results in high carbon emission intensity. To peak China’s carbon emissions and achieve the carbon neutrality target, it is essential to accelerate the application of breakthrough technologies such as carbon capture and storage (CCS) and hydrogen-based steel-making. This paper estimates the future CO₂ emissions from China’s iron and steel industry in pathways that consider the influence of different technology portfolios, technology maturity, decarbonization of power systems, and future steel production output. The results show that using currently available technology, China’s iron and steel industry can reduce CO₂ emissions by more than 50%. However, it cannot achieve the neutrality target without using innovative technologies. By combining conventional strategies with net-zero emission technologies such as CCS and hydrogen metallurgy, approximately 80–90% emission reduction can be achieved, thus leading to a carbon neutrality pathway, which can meet the 1.5°C targets of the carbon budget limit either. In the future, carbon emissions' reduction potential will be influenced by the decarbonization of power systems and the diffusion rate of innovative technologies. To achieve carbon neutrality, it is essential to act sooner and faster.     

Mapping public appraisals of carbon dioxide removal

Efforts to deliver on net zero emissions targets are set to rely on carbon dioxide removal (CDR) methods. Democratic, trustworthy and socially intelligent research, development, demonstration and deployment of CDR methods in aid of net zero will be highly dependent on how different publics evaluate them, and ultimately which groups support or oppose them. This paper develops a novel, nationally representative method for the multi-criteria appraisal of five policy relevant CDR methods – plus an option not to pursue CDR at all – by members of the British public (n = 2,111). The results show that the public supports the inclusion of CDR in UK climate policy. CDR methods often characterised as ‘natural’ or ‘nature-based’ are appraised more highly than ‘technological’ ones, in the descending order: habitat restoration, afforestation, wood in construction, bioenergy with carbon capture and storage, and direct air carbon capture and storage. Yet, there is no significant disagreement in the appraisal of technological methods and they therefore may be less polarizing, suggesting that popular preconceptions of what is natural – and therefore more attractive – may be holding them back. CDR methods being mainly developed by public sector and non-governmental organisations are also appraised more highly than those being developed by private interests. Regional differences in option appraisal reveal where particular CDR methods are more or less likely to be supported or opposed; stressing the importance of matching physical requirements for CDR with appropriate social contexts. Demographic and socio-economic analyses show that people who appraise CDR methods most highly tend to be older respondents, male, or of a higher social grade. Finally, those with hierarchical worldviews and who voted ‘leave’ in the UK’s referendum on EU membership are less supportive of CDR than those with egalitarian worldviews and who voted ‘remain’.     

Forty‐Nine Major and Trace Element Concentrations Measured in Soil Reference Materials NIST SRM 2586, 2587, 2709a, 2710a and 2711a Using ICP‐MS and Wavelength Dispersive‐XRF

Excellent agreement was noted in the concentration of major and trace elements in five NIST (National Institute for Science and Technology) soil reference materials (NIST SRM 2586, 2587, 2709a, 2710a and 2711a) between measurement results from wavelength dispersive‐XRF and ICP‐MS from two independent laboratories, and NIST certificate of analysis and literature data. We describe the variability in concentrations of up to forty‐nine elements (plus loss on ignition) and provide values for up to twenty‐one elements previously uncharacterised by NIST in these soil RMs. The additional characterisation provided in this investigation can be utilised to reduce the measurement bias of custom calibration routines and improve the quality of control checks developed using these NIST RMs.