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The foundation of the 2015 Paris climate agreement was to a large extent based on cooperation between the United States and China on clean energy and emissions reductions. With the United States now planning to withdraw from the agreement, who will replace them? Ahead of the United Nations climate conference in Bonn that begins next week, the spotlight is on Germany to fill the vacancy. Indeed, there is a strong common ground upon which Germany and China can collaborate to show the world a positive picture of a low-carbon transition. If they work together on renewable energy, a sustainable transport system, and effective policies, these two nations could change the course of the global low-carbon pathway.

Many countries have implemented national climate policies to accomplish pledged Nationally Determined Contributions and to contribute to the temperature objectives of the Paris Agreement on climate change. In 2023, the global stocktake will assess the combined effort of countries. Here, based on a public policy database and a multi-model scenario analysis, we show that implementation of current policies leaves a median emission gap of 22.4 to 28.2 GtCO 2 eq by 2030 with the optimal pathways to implement the well below 2 °C and 1.5 °C Paris goals. If Nationally Determined Contributions would be fully implemented, this gap would be reduced by a third. Interestingly, the countries evaluated were found to not achieve their pledged contributions with implemented policies (implementation gap), or to have an ambition gap with optimal pathways towards well below 2 °C. This shows that all countries would need to accelerate the implementation of policies for renewable technologies, while efficiency improvements are especially important in emerging countries and fossil-fuel-dependent countries. To evaluate the effectiveness of current national policies in achieving global temperature targets is important but a systematic multi-model evaluation is still lacking. Here the authors identified a reduction of 3.5 GtCO 2 eq of current national policies relative to a baseline scenario without climate policies by 2030 due to the increasing low carbon share of final energy and the improving final energy intensity.

Significant energy transition would be needed in China under the carbon neutrality target. Since it would have important impacts on water resource through increased usage, understanding the water demand under specific climate change targets could enable better policy-making for the energy transition. In order to quantitatively analyze the impacts, this study proposed a methodology that combines CO 2 emissions, energy transition, and water demand. An energy-water integrated assessment model was built, to simulate the future energy and CO 2 emissions pathways up to 2050 in China. The water demand of energy systems under both policy scenario (PS) and two mitigation scenarios (2C and 1.5C) are calculated. The key influencing factors of water demand are analysed in two low-water-demand mitigation scenarios (2C-LW and 1.5C-LW). The results showed that China's future energy system and CO 2 emissions pathways change significantly under mitigation scenarios. The timing of the CO 2 emissions peak advances from around 2030 under the PS scenario to between 2020 and 2025 in the mitigation scenarios. Near-zero emissions are achieved by 2050 under the 1.5C scenario. However, with no further water-saving measures, water consumption in energy sector would continue to increase under both the policy scenario and mitigation scenarios. This pressure is compounded by certain mitigation technologies, such as inland nuclear power, biomass energy, and CCS technologies. As such, the potential for water conservation in energy system under climate mitigation targets is studied. The results showed that water-saving measures can significantly reduce long-term water demand in the energy system.

X80 pipeline steel is a key material in the field of oil and gas transportation. Its damage behavior in a hydrogen-filled environment directly affects pipeline safety. In this study, through hydrogen permeation experiments and slow strain rate tensile tests, the electrochemical responses and hydrogen-induced cracking behaviors of X80 base metal and welded joints under hydrogen filling conditions in both AC and DC were systematically compared. The results show that when the base material is filled with hydrogen at 20 mA/cm AC, the hydrogen permeation flux is the largest, and the overall hydrogen permeation parameter of the welded joint is lower than that of the base material. High-frequency polarization promotes hydrogen permeation, but anodic corrosion products at high current densities can impede hydrogen entry. The slow strain rate tensile test further confirmed that the mechanical properties of the material declined more significantly under direct current hydrogen charging, and the sensitivity to stress corrosion cracking was higher. Under alternating hydrogen charging conditions, due to the alternating effects of hydrogen charging at the cathode and corrosion at the anode, a relatively low hydrogen embrittlement sensitivity is exhibited.

Emission reduction from the coal-dominated power sector is vital for achieving China's carbon mitigation targets. Although the coal expansion has been slowed down due to the cancellation of and delay in new construction, coal-based power was responsible for over one third of China's energy-related CO2 emissions by 2018. Moreover, with a technical lifetime of over 30 years, current investment in coal-based power could hinder CO2 mitigation until 2050. Therefore, it is important to examine whether the current coal-based power planning aligns with the long-term climate targets. This paper introduces China's Nationally Determined Contribution (NDC) goals and an ambitious carbon budget along with global pathways well-below 2 degrees that are divided into five integrated assessment models, which are two national and three global models. We compare the models' results with bottom-up data on current capacity additions and expansion plans to examine if the NDC targets are in line with 2-degree pathways. The key findings are: 1. NDC goals alone are unlikely to lead to significant reductions in coal-based power generation. On the contrary, more plants may be built before 2030; 2. this would require an average of 187-261 TWh of annual coal-based power capacity reduction between 2030 and 2050 to achieve a 2 °C compatible trajectory, which would lead to the stranding of large-scale coal-based power plants; 3. if the reduction in coal power can be brought forward to 2020, the average annual coal-based power reduction required would be 104-155 TWh from 2020 to 2050 and the emissions could peak earlier; 4. early regulations in coal-based power would require accelerated promotion of alternatives between 2020 and 2030, with nuclear, wind and solar power expected to be the most promising alternatives. By presenting the stranding risk and viability of alternatives, we suggest that both the government and enterprises should remain cautious about making new investment in coal-based power sector.

● A WECA model evaluates water withdrawal and WEQ of typical EVRs' transition. ● Synergetic pathways of water-energy-carbon to carbon neutrality are proposed. ● Electricity production can escalate WEQ due to industrial transition. ● Limited effects from zero-carbon transition on improving water environment quality. Synergetic energy-water-carbon pathways are key issues to be tackled under carbon-neutral target and high-quality development worldwide, especially in ecologically vulnerable regions (EVRs). In this study, to explore the synergistic pathways in an EVR, a water-energy-carbon assessment (WECA) model was built, and the synergistic effects of water-energy-carbon were comprehensively and quantitatively analyzed under various scenarios of regional transition. Shaanxi Province was chosen as the representative EVR, and Lower challenge (LEC) and Greater challenge (GER) scenarios of zero-carbon transition were set considering the technological maturity and regional energy characteristics. The results showed that there were limited effects under the zero-carbon transition of the entire region on reducing water withdrawals and improving the water quality. In the LEC scenario, the energy demand and CO 2 emissions of Shaanxi in 2060 will decrease by 70.9% and 99.4%, respectively, whereas the water withdrawal and freshwater aquatic ecotoxicity potential (FAETP) will only decrease by 8.9% and 1.6%, respectively. This could be attributed to the stronger demand for electricity in the energy demand sector caused by industrial transition measures. The GER scenario showed significant growth in water withdrawals (16.0%) and FAETP (36.0%) because of additional biomass demand. To promote the synergetic development of regional transition, EVRs should urgently promote zero-carbon technologies (especially solar and wind power technologies) between 2020 and 2060 and dry cooling technology for power generation before 2030. In particular, a cautious attitude toward the biomass energy with carbon capture and storage technology in EVRs is strongly recommended.

In China, Energy transition was proposed in the “12th Five-Year Plan” and gained resilient support by “Energy Revolution” announced by President Xi Jinping in 2014. In Paris Agreement, there are targets set up for 2100 to be well below 2 °C, with ambitious target on 1.5 °C. China signed the agreement and will support the global target. In the meantime, large-scale actions were initiated in 2013 by the national action plan on air pollution control for the period from 2013 to 2017. None of these strategies has clear long-term target. In our studies, energy transition will be decided by the long-term target of CO2 emission reduction, air pollutant reduction, and energy security. This paper will present the analysis from IPAC model, by setting up reduction target for CO2 emission under the global 2 °C and 1.5 °C target. Energy transition, CO2 emission, and air pollutant reduction will be discussed based on these targets. For air pollutants, SO2, NOx, PM2.5, black carbon, and mercury will be included. From the results, there will be a significant energy transition by large-scale use of renewable energy, nuclear and the share of coal will be reduced to less than 20% in 2050 from 66% in 2015. Energy transition will also contribute to a drastic reduction in air pollutants.

Glioma, one of the most common brain tumors, remains a challenge worldwide. Due to the specific biological barriers such as blood-brain barrier (BBB), cancer stem cells (CSCs), tumor associated macrophages (TAMs), and vasculogenic mimicry channels (VMs), a novel versatile targeting delivery for anti-glioma is in urgent need. Here, we designed a hyaluronic acid (HA) ion-pairing nanoparticle. Then, these nanoparticles were encapsulated in liposomes, termed as DOX-HA-LPs, which showed near-spherical morphology with an average size of 155.8 nm and uniform distribution (PDI = 0.155). HA was proven to specifically bind to CD44 receptor, which is over-expressed on the surface of tumor cells, other associated cells (such as CSCs and TAMs) and VMs. We systematically investigated anti-glioma efficacy and mechanisms in vivo and in vitro. The strong anti-glioma efficacy could attribute to the accumulation in glioma site and the regulation of tumor microenvironment with depletion of TAMs, inhibition of VMs, and elimination of CSCs.

This paper proposes to the analysis of Russia’s energy strategy, with respect to the interconnection of governmental strategy concerning energy extraction, reproduction and distribution and corporate energy strategies. The current trends in Russian energy strategy have been studied on the back ongoing processes in Russian corporate energy strategy formulation, with the use of statistical analysis of total volume of energy generated over the period from each source. The conclusions on areas for development and key drivers of corporate energy strategy have been made.

Biomass has been widely recognized as an important energy source with high potential to reduce greenhouse gas emissions while minimizing environmental pollution. In this study, we employ the Global Change Assessment Model to estimate the potential of agricultural and forestry residue biomass for energy production in China. Potential availability of residue biomass as an energy source was analyzed for the 21st century under different climate policy scenarios. Currently, the amount of total annual residue biomass, averaged over 2003–2007, is around 15 519 PJ in China, consisting of 10 818 PJ from agriculture residues (70%) and 4701 PJ forestry residues (30%). We estimate that 12 693 PJ of the total biomass is available for energy production, with 66% derived from agricultural residue and 34% from forestry residue. Most of the available residue is from south central China (3347 PJ), east China (2862 PJ) and south‐west China (2229 PJ), which combined exceeds 66% of the total national biomass. Under the reference scenario without carbon tax, the potential availability of residue biomass for energy production is projected to be 3380 PJ by 2050 and 4108 PJ by 2095, respectively. When carbon tax is imposed, biomass availability increases substantially. For the CCS 450 ppm scenario, availability of biomass increases to 9002 PJ (2050) and 11 524 PJ (2095), respectively. For the 450 ppm scenario without CCS, 9183 (2050) and 11 150 PJ (2095) residue biomass, respectively, is projected to be available. Moreover, the implementation of CCS will have a little impact on the supply of residue biomass after 2035. Our results suggest that residue biomass has the potential to be an important component in China's sustainable energy production portfolio. As a low carbon emission energy source, climate change policies that involve carbon tariff and CCS technology promote the use of residue biomass for energy production in a low carbon‐constrained world.