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Limiting climate change to 1.5°C and achieving net-zero emissions would entail substantial carbon dioxide removal (CDR) from the atmosphere by the mid-century, but how much CDR is needed at country level over time is unclear. The purpose of this paper is to provide a detailed description of when and how much CDR is required at country level in order to achieve 1.5°C and how much CDR countries can carry out domestically. We allocate global CDR pathways among 170 countries according to 6 equity principles and assess these allocations with respect to countries biophysical and geophysical capacity to deploy CDR. Allocating global CDR to countries based on these principles suggests that CDR will, on average, represent ∼4% of nations total emissions in 2030, rising to ∼17% in 2040. Moreover, equitable allocations of CDR, in many cases, exceed implied land and carbon storage capacities. We estimate ∼15% of countries (25) would have insufficient land to contribute an equitable share of global CDR, and ∼40% of countries (71) would have insufficient geological storage capacity. Unless more diverse CDR technologies are developed, the mismatch between CDR liabilities and land-based CDR capacities will lead to global demand for six GtCO2 carbon credits from 2020 to 2050. This demonstrates an imperative demand for international carbon trading of CDR.

Confined fluids and electrolyte solutions in nanopores exhibit rich and surprising physics and chemistry that impact the mass transport and energy efficiency in many important natural systems and industrial applications. Existing theories often fail to predict the exotic effects observed in the narrowest of such pores, called single-digit nanopores (SDNs), which have diameters or conduit widths of less than 10 nm, and have only recently become accessible for experimental measurements. What SDNs reveal has been surprising, including a rapidly increasing number of examples such as extraordinarily fast water transport, distorted fluid-phase boundaries, strong ion-correlation and quantum effects, and dielectric anomalies that are not observed in larger pores. Exploiting these effects presents myriad opportunities in both basic and applied research that stand to impact a host of new technologies at the water-energy nexus, from new membranes for precise separations and water purification to new gas permeable materials for water electrolyzers and energy-storage devices. SDNs also present unique opportunities to achieve ultrasensitive and selective chemical sensing at the single-ion and single-molecule limit. In this review article, we summarize the progress on nanofluidics of SDNs, with a focus on the confinement effects that arise in these extremely narrow nanopores. The recent development of precision model systems, transformative experimental tools, and multiscale theories that have played enabling roles in advancing this frontier are reviewed. We also identify new knowledge gaps in our understanding of nanofluidic transport and provide an outlook for the future challenges and opportunities at this rapidly advancing frontier.

Abstract Background Trigger finger is a common condition in the hand, and ultrasound-guided acupotomy for trigger finger has been widely used in recent years. Purpose This study aims to investigate the efficacy and safety of ultrasound-guided acupotomy for trigger finger. Methods We searched for relevant studies in the Cochrane Library, China National Knowledge Infrastructure (CNKI), Embase, PubMed, Chinese Biomedical Literature Database (CBM), Wanfang Data, and other resources from their inception to January 2023. Randomized controlled trials of ultrasound-guided acupotomy for trigger finger were included. The meta-analysis was carried out using Review Manager 5.4 and Stata 15.1. Results Overall, 15 studies with 988 patients were included. The experimental group was treated with ultrasound-guided acupotomy, and the Control group received traditional acupotomy, traditional operation or injection of medication. Meta-analysis showed that the overall clinical effectiveness (OR = 4.83; 95% CI 2.49–9.37; I 2 = 73.1%; P

Drug delivery mitigates toxic side effects and poor pharmacokinetics of life-saving therapeutics and enhances treatment efficacy. However, direct cytoplasmic delivery of drugs and vaccines into cells has remained out of reach. We find that liposomes studded with 0.8-nm-wide carbon nanotube porins (CNTPs) function as efficient vehicles for direct cytoplasmic drug delivery by facilitating fusion of lipid membranes and complete mixing of the membrane material and vesicle interior content. Fusion kinetics data and coarse-grained molecular dynamics simulations reveal an unusual mechanism where CNTP dimers tether the vesicles, pull the membranes into proximity, and then fuse their outer and inner leaflets. Liposomes containing CNTPs in their membranes and loaded with an anticancer drug, doxorubicin, were effective in delivering the drug to cancer cells, killing up to 90% of them. Our results open an avenue for designing efficient drug delivery carriers compatible with a wide range of therapeutics.

Carbon nanotube (CNT) pores, which mimic the structure of the aquaporin channels, support extremely high water transport rates that make them strong candidates for building artificial water channels and high-performance membranes. Here, we measure water and ion permeation through 0.8-nm-diameter CNT porins (CNTPs)-short CNT segments embedded in lipid membranes-under optimized experimental conditions. Measured activation energy of water transport through the CNTPs agrees with the barrier values typical for single-file water transport. Well-tempered metadynamics simulations of water transport in CNTPs also report similar activation energy values and provide molecular-scale details of the mechanism for water entry into these channels. CNTPs strongly reject chloride ions and show water-salt permselectivity values comparable to those of commercial desalination membranes.

Rainfall-induced landslides are the most common geological hazard in the world, and the effect of preferential flow infiltration has been neglected for a long time regarding the slope reliability analysis under rainfall infiltration. The preferential infiltration under rainfall conditions is solved numerically by Comsol Multiphysics, and the slope factor of safety is calculated using an infinite slope model. An improved Cholesky decomposition method is applied to generate spatially correlated random fields, and the slope reliability during rainfall is analyzed using the Monte Carlo method. Combining the deterministic and reliability results to compare the variation of slope factor of safety between the homogeneous infiltration and the preferential infiltration during rainfall, it can be found that: (1) the preferential infiltration model is safer when the rainfall intensity is low, while the homogeneous infiltration is more stable at higher rainfall intensity; (2) the spatial variability of infiltration parameters is the crucial factor of slope failure in homogeneous infiltration, while the slope instability of preferential infiltration is mainly caused by the rapid advance of the wetting front; (3) for the study of preferential infiltration model, the slope has a higher probability of failure when the hydraulic exchange intensity between the matrix domain and the preferential domain, while smaller hydraulic exchange intensity may affect the slope failure at the bottom.

Uranium is an indispensable element for the development of nuclear energy. Uranium extraction from seawater can effectively solve the problem of the shortage in land uranium mines. Amidoxime(AO)-based adsorbents exhibit excellent adsorption performance for uranyl ions. This article reviews the research progress of AO-based fiber since it has been reported, analyzes the preparation method and adsorption performance of AO-based fibrous adsorbent, and studies the development process and trend of this type of materials. Furthermore, the existing issues of the current industrialization of AO-based fibrous materials is discussed. Finally, the development of uranium extraction from seawater in the future is prospected.

The goaf formed by mining and other activities is prone to safety hazards. Preparing high-quality and low-cost solidified iron tailings powder (SITP) is an important way to ensure backfill quality and eliminate safety hazards. Using iron tailings powder near the goaf of in Shanxi, comparative experiments were conducted to evaluate the the flowability, stone rate, strength, and water stability of newly mixed SITP under different types and dosages of curing agent, and mixing methods. The results show that under the premise of keeping the fluidity constant, the strength of the ITP slurry increases with the increase of the curing agent content; At the same strength, the water consumption significantly affects the fluidity; When using 8%~16% different curing agent dosage, the expansion degree is 280 mm ~ 600 mm, the wet density is 1.9 g/cm3 ~ 2.1 g/cm3, the 28d strength after curing is 1.4 MPa ~ 3.7 MPa, and the stone rate is greater than 92%; The ITP slurry prepared by vibration mixing with a mixing time of 120 s and the amount of curing agent at 8% meets the engineering application requirements of 7d strength of 0.6 MPa and expansion of 250 mm. The research shows that the iron tailings powder slurry prepared by vibration mixing has high strength after solidification, and it is a new way of resource utilization of iron tailings powder with large consumption and good economy to be used for goaf backfilling. [ABSTRACT FROM AUTHOR]

Flue gas recirculation technology and air-staged combustion technology are both effective methods for reducing the production of NOX in coal-fired boilers. However, the synergistic effect of air-staged combustion technology and flue gas recirculation technology on NOX generation characteristics in S-CO2 boilers needs further study. The formation characteristics of NOX in the main combustion zone of coal combustion were studied experimentally when flue gas recirculation and air-staged combustion were combined. The results indicate that as the recirculation flue gas is injected at deeper levels, there is a gradual decrease in the concentration of NOX along the path, And the concentration of O2 also decreases gradually. The concentration of NOX decreases as the excess air coefficient decreases. The concentration of O2 increases as the excess air coefficient increases. Additionally, the NOX concentration at the furnace outlet increases with the increase of the excess air coefficient. Along the axial direction of the one-dimensional flame combustion furnace, the NOX production along the way and the NOX concentration at the outlet decrease with the increase of the flue gas recirculation position. Flue gas recirculation in air-staged combustion is an effective method for reducing NOX emissions. The positioning of flue gas recirculation significantly impacts NOX emissions. The NOx concentration is lowest when the flue gas recirculation rate is 27% and the mixing position of the recirculated flue gas is 300 mm with an excess air coefficient of 0.8. [ABSTRACT FROM AUTHOR]