Hydrogen has increasingly been an attractive energy in the context of carbon neutrality. The traditional coal-to-hydrogen process (C2H) is cost-effective, while has high CO2 emissions. In contrast, ...low-carbon hydrogen production technologies such as coal-to-hydrogen coupled CCS (C2HCCS) and renewable energy electrolysis of water for hydrogen production may be climate friendly, but of the economic feasibility needs to be evaluated. This study analyzed the production cost, cost structure and regional differences of C2H, C2HCCS, alkaline electrolysis (ALK), and proton exchange membrane electrolysis (PEM) in China via the levelized cost of hydrogen (LCOH) model. The main findings include: (1) The LCOH of the C2HCCS is 13.1–19.4RMB/kg, which is 57.6–128.3% higher than the coal-to-hydrogen process (7.2–10.1RMB/kg), and 20.5–61.0% lower than that of the hydrogen production via the water electrolysis powered by renewable energy (16.4–51.8RMB/kg). (2) The C2HCCS can be considered as a cost-effectiveness option in northwestern regions of China, especially in the provinces of Inner Mongolia, Xinjiang, and Gansu, for the future blue hydrogen energy industry. (3) Currently, hydrogen production via renewable energy-based water electrolysis has no cost advantage in most regions, but wind power-based electrolysis in Gansu and photovoltaic power-based electrolysis in Chongqing have the potential to compete with the C2HCCS process.
•The levelized costs of low-carbon hydrogen production technologies were evaluated.•High initial capital cost greatly limits the development of low-carbon hydrogen.•Coal-to-hydrogen with CCS is usually cost-effective in northern China.•Gansu and Chongqing have great potential for hydrogen production by renewable energy.•Regional advantages of various processes help reduce the cost of hydrogen production.
The oxygen evolution reaction (OER) is involved in various renewable energy systems, such as water‐splitting cells and metal–air batteries. Ni‐Fe layered double hydroxides (LDHs) have been reported ...as promising OER electrocatalysts in alkaline electrolytes. The rational design of advanced nanostructures for Ni‐Fe LDHs is highly desirable to optimize their electrocatalytic performance. Herein, we report a facile self‐templated strategy for the synthesis of novel hierarchical hollow nanoprisms composed of ultrathin Ni‐Fe LDH nanosheets. Tetragonal nanoprisms of nickel precursors were first synthesized as the self‐sacrificing template. Afterwards, these Ni precursors were consumed during the hydrolysis of iron(II) sulfate for the simultaneous growth of a layer of Ni‐Fe LDH nanosheets on the surface. The resultant Ni‐Fe LDH hollow prisms with large surface areas manifest high electrocatalytic activity towards the OER with low overpotential, small Tafel slope, and remarkable stability.
A self‐templated strategy enables the synthesis of hierarchical hollow nanoprisms composed of ultrathin Ni‐Fe layered double hydroxide (LDH) nanosheets. During the hydrolysis of iron(II) sulfate, prism‐like Ni precursors are dissolved and converted into a shell of Ni‐Fe LDH on their surface. Owing to structural and compositional advantages, these hollow nanoprisms display enhanced electrochemical activity in the oxygen evolution reaction.
•CCS technology lock-in risk of coal-fired power plants in China was considered.•The cost of CCS commercialization in different scenarios was evaluated.•CCS retrofit potential of coal-fired power ...plants in China was explored.•Suggestions on CCS promotion and avoiding CCS technology lock-in were put forward.
Carbon capture and storage (CCS) has been discussed intensively in China; however, the CCS technology lock-in risk has been neglected for a long time and may have a negative impact on understanding the CCS application potential. Thus, from the perspective of avoiding a technology lock-in, a learning curve model and a cost-optimization model are employed in this study to explore the total cost of CCS commercialization and the national and provincial CCS retrofit potential of coal-fired power plants in China. The results show that if the second-generation CCS technologies are not commercially applied by 2040, coal-fired power plants in China may face a huge risk of being locked in by the first-generation technologies with a retrofit potential of only 0–143.63 GW (GW = 106 kW) and a cost of 13.39 billion USD. Advancing the CCS commercialization time to 2030 can reduce the technology lock-in risk greatly and increase the CCS retrofit potential to 431.01–499.90 GW, which would cost 54.3 billion USD. Considering the cost input, the technology lock-in risk, and the CCS retrofit demand, 2035 is regarded a suitable time for CCS commercialization in China with a retrofit potential of 143.63–431.04 GW and 31.46 billion USD cost input. Moreover, at the regional level, there is a great CCS retrofit potential of coal-fired power plants in Shaanxi, Hebei, and Inner Mongolia. Policymakers should provide greater support for the second-generation CCS technologies and promote them actively in 2030–2035, especially in Shaanxi, Hebei, and Inner Mongolia, to achieve CCS commercialization and control the CO2 emissions of coal-fired power plants in China.
China is a coal dominated country, where CCS has a great potential to be used in coal-fired power plants (CFPP) but it is limited by the high investment cost. The competitiveness of the CFPP that ...responsible for the entire chain of carbon capture, the transportation and storage (CPCCS) was compared with the natural gas combined cycle power plants (NGCC), the centralized solar photovoltaic power station (CPV), the on-shore wind farms (WF), and the agro-forestry biomass direct combustion power plants (BPP), through calculating the levelized cost of electricity (LCOE) at the same emission reduction level from the national and regional perspectives. The results showed that 1) the CPCCS had an advantage over other technologies when it had suitable storage sites within short distances and low coal prices. 2) The LCOE of the CPCCS was effectively affected by the CO2 transportation distance and the coal price. The initial investment cost of the CPV and WF, as well as the fuel price of the NGCC and the BPP were the decisive factors for their LCOE. 3) The LCOE of the CPCCS had the largest advantage in Shanxi, Tianjin, Gansu, and Xinjiang when compared to the NGCC, BPP, CPV, and WF.
•The competitiveness of CPCCS for NGCC, CPV, WF and BPP was clarified.•The LCOE’s structure of CPCCS in China was shown out.•The distance to storage sites and coal price were significant factors for CPCCS.•The LCOE advantage of CPCCS demonstrated due to different regional resources.
•A high precision CCUS source-sink matching model was proposed.•Deployment potential of CCUS in coal-fired power plants in China was evaluated.•Early opportunities for China to develop CCUS were ...identified.•Suggestions on CCUS deployment in China were put forward.
Carbon capture utilization and storage is regarded as an important option to achieve deep CO2 reduction in the power sector, especially in China. An optimization model was developed without considering the CCUS costs constraints to determine the CO2 reduction potential of existing coal-fired power plants with CCUS in China from the perspective of source-sink matching. Saline aquifers and oil fields located in major onshore sedimentary basins in China were considered as potential sinks. The results showed that: i) the storage potential of the saline aquifers and enhanced oil recovery are over 1 × 1012 t and 5 × 109 t, respectively; ii) 401 power plants could be matched with storage sites within 100 km without considering the CO2 injection capacity, and the annual CO2 sequestration amount was about 1204 Mt. If the maximum transport distance were increased to 250 km and 800 km, respectively, and the annual CO2 sequestration amount would more than 1620 Mt and 1017 Mt. iii) The CO2 sequestration amount would be cut by about 2% to 38% if the CO2 injection capacity was considered as a constraint; the sequestration amount was primarily affected by the transport distance. iv) Junggar Basin, Turpan-Hami Basin, Ordos Basin, Songliao Basin, and Bohai Bay Basin were considered priority areas to deploy carbon capture utilization and storage technology, including CO2 enhanced oil recovery.
Electricity sector is sensitive to climate change. In this study, a fixed-effect regression feedback model is used to estimate the impacts of climatic factors on electricity demand in China by using ...panel data of 30 provinces from 1995 to 2016. We also forecast the potential impacts of climate change on future electricity demand under three climate change scenarios. The results show that (1) there is a positive effect of the heating degree day (HDD) and cooling degree day (CDD) on the per capita electricity demand. A 1% increase in the CDD will result in a 0.094% increase in per capita electricity demand, while the same rise of HDD will increase per capita electricity demand by 0.061%. In addition, the per capita electricity demand will decrease by 0.017% if the sunshine duration increases 1%, while the effect of rainfall is not significant. (2) The total changes in electricity demand caused by climatic factors by 2100 under the RCP2.6, RCP4.5, and RCP8.5 scenarios will be 69.52 billion kWh, 222.74 billion kWh, and 518.58 billion kWh, representing 1.0%, 3.53%, and 8.53% of the total electricity consumption in China in 2017, respectively. The effect of climate warming on China's electricity demand is apparent.
•A climate change feedback model on electricity demand in China is presented.•Temperature is the main climatic factor driving electricity demand.•Significant impacts of the macroeconomic variables on the electricity demand are found.•Significant growth in cooling electricity demand are predicted in China.
We consider a scheduling problem where a set of jobs are first processed on a machine with an unavailability interval and, then, delivered to the customer directly. We focus on an integrated schedule ...of production and distribution such that the sum of the maximum delivery time and total delivery cost is optimized. We study two classes of processing machines in the production part. In the first class, the serial-batch machine, the processing time of a batch is the sum of the processing times of its jobs. In the second class, the parallel-batch machine, the processing time of a batch is the maximum processing time of the jobs contained in the batch. The machine has a fixed capacity, and the jobs are processed in batches under the condition that the total size of the jobs in a batch cannot exceed the machine capacity. Two patterns of job’s processing, i.e., resumable and non-resumable, are considered if it is interrupted by the unavailability interval on the machine. In the distribution part, there are sufficient vehicles with a fixed capacity to deliver the completed jobs. The total size of the completed jobs in one delivery cannot exceed the vehicle capacity. We show that these four problems are NP-hard in the strong sense in which the jobs have the same processing times and arbitrary sizes, and we propose an approximation algorithm for solving these four problems. Moreover, we show that the performance ratio of the algorithm is 2 for the serial-batch machine setting, and the error bound is 71/99 for the parallel-batch machine setting. We also evaluate the performance of the approximation algorithm by the computational results.
The cleaning of cement warehouse is a labor-intensive and high-risk operation. The applicability and cleaning effect of traditional work tools are poor. Therefore, most of the methods are manual ...cleaning, which is inefficient and prone to accidents. It is of great social significance and practical value to develop an intelligent flexible warehouse cleaning robot that replaces the manual cleaning of cement. When the top of the cement warehouse is small and the volume of the cement warehouse is very large, how to ensure that the working range of the cleaning system can cover the entire area, and effectively and quickly complete the cleaning operation, and the automatic control of the cleaning robot has become an automatic control. Key issues to be addressed. Although the human–machine interface configuration technology has been widely used in automated monitoring systems, its graphical and componentized interface construction methods and the flexibility and scalability of the configuration interface have been widely recognized, but the human–machine interface, the coding method is still used in the construction, the development efficiency is low, and the interface is not open and flexible enough. At the same time, there are few research attempts on interface configuration. Interface configuration mostly only stays in the graphical phase of interface construction. Data and interactive control cannot meet the configuration requirements, and there is no complete implementation plan for configuration. Therefore, it has become an urgent need to change the traditional interface development mode and realize the configuration of man–machine interface. Based on the above background, the research content of this article is the research on the automatic control system of intelligent flexible clearing robot. Based on the understanding of the relevant properties of cement powder, this article discusses its flow state in the cement storehouse theoretically and provides a basis for subsequent structural design and stability research. A modularized and component-based configuration method for the numerical control interface is proposed. The interface is divided into three modules: data, graphics, and interactive control. The functional modules are assembled and the components are combined to implement the interface configuration. The experimental simulation results in this article show that compared to the traditional method, the amount of code editing of the configured human–machine interface is reduced by 46.34%, the development cycle is shortened by 43.72%, and the development efficiency of the configured human–machine interface has been greatly improved. It is confirmed that the configuration technology studied in this article can meet the requirements of automatic control systems.
Mitochondria and cell membrane play important roles in maintaining cellular activity and stability. Here, a single-agent self-delivery chimeric peptide based nanoparticle (designated as M-ChiP) was ...developed for mitochondria and plasma membrane dual-targeted photodynamic tumor therapy. Without additional carrier, M-ChiP possessed high drug loading efficacy as well as the excellent ability of producing reactive oxygen species (ROS). Moreover, the dual-targeting property facilitated the effective subcellular localization of photosensitizer protoporphyrin IX (PpIX) to generate ROS in situ for enhanced photodynamic therapy (PDT). Notably, plasma membrane-targeted PDT would enhance the membrane permeability to improve the cellular delivery of M-ChiP, and even directly disrupt the cell membrane to induce cell necrosis. Additionally, mitochondria-targeted PDT would decrease mitochondrial membrane potential and significantly promote the cell apoptosis. Both in vitro and in vivo investigations indicated that this combinatorial PDT in mitochondria and plasma membrane could achieve the therapeutic effect maximization with reduced side effects. The single-agent self-delivery system with dual-targeting strategy was demonstrated to be a promising nanoplatform for synergistic tumor therapy.
Recycling of molybdenum isotopes in continental subduction zones remains debated. In this contribution, we re‐visit the Mo isotope compositions of the Sailipu post‐collisional ultrapotassic rocks in ...the Himalaya‐southern Tibet orogen. These ultrapotassic rocks have very varying δ98/95Mo values of −0.66 to −0.07‰ and Mo/Ce ratios of 0.0008–0.005, which are lower than those of mid‐ocean ridge basalts (MORB; δ98/95Mo = −0.20 ± 0.06‰, and Mo/Ce = 0.03) and oceanic subduction‐related (i.e., mantle source involving fluids, residual slab, or oceanic sediments) magmatic rocks (e.g., modern arc lavas, Cenozoic OIB‐type basalts in eastern China and the central Mariana Trough basalts in the back‐arc basin, syn‐collisional andesitic rocks in southern Tibet). Combined with the light Mo isotopes of the Himalayan schists and gneisses, we suggest that the light Mo isotopic signature of the Sailipu ultrapotassic rocks is derived from subducted Indian continental crust. This is consistent with the extremely low δ11B (−17.4 to −9.7‰) and B/Nb (0.16–1) values and enriched Sr‐Nd‐Pb isotopes of the Sailipu ultrapotassic rocks. Thus, this study reveals the recycling of light Mo‐B isotopes during continental subduction and demonstrates that Mo‐B isotopes can effectively distinguish between continental and oceanic subduction.
Plain Language Summary
Mo isotope systematics have been widely applied in the study of tracing recycled crustal materials, and abundant researches have proposed that heavy Mo isotopic compositions of arc‐mafic magma can be ascribed to slab‐dehydrated fluids. However, in continental subduction zones, the origin of the light Mo isotopes of post‐collisional mafic rocks (oceanic sediments during prior oceanic subduction vs. subducted continental crust) remains controversial, hindering our understanding of the recycling of continental crustal materials. In this study, we report new Mo isotope data of post‐collisional ultrapotassic rocks in the Lhasa block of the southern Tibetan plateau. We have used Mo isotope data along with B‐Sr‐Nd‐Pb isotopes of these ultrapotassic rocks, in combination with Mo‐B‐Sr‐Nd‐Pb isotopes of the Himalayan crustal rocks (e.g., gneisses and schists) to trace the crustal components in the post‐collisional mantle beneath southern Tibet. We concluded that the light Mo and B isotope compositions in southern Tibet were derived from subducted Indian continental crust rather than Neo‐Tethyan oceanic sediments. Thus, this study not only reveals the recycling of light Mo‐B isotopes in this typical collision orogen (i.e., Himalaya‐Tibet orogen) but also shows the potential in discriminating between oceanic subduction metasomatism and continental subduction metasomatism.
Key Points
Post‐collisional ultrapotassic rocks in southern Tibet have extremely light Mo and B isotope compositions
These light Mo‐B isotope features are derived from subducted Indian continental crust
Mo‐B isotopes have the potential to discriminate between oceanic and continental subduction
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