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With the aim of “carbon peaking” and “carbon neutrality” in China, hydrogen energy will play a crucial role of in the future. The third-generation nuclear power (GEN-Ⅲ) features a relatively low reactor outlet temperature, with the primary application of its generated electric energy to direct electrolysis of water to produce hydrogen. In contrast, the fourth-generation nuclear power (GEN-Ⅳ) has higher thermal efficiency and reactor outlet temperature. Considering the matching of reactor outlet temperature with the hydrogen production process, cogeneration can be employed to effectively reduce the cost of hydrogen production. Sodium-cooled fast reactor (SFR) is one of the GEN-Ⅳ reactors, which has the advantage of high reactor outlet temperature, high efficiency and high-tech maturity, and can provide the thermal power and electrical energy for the hydrogen production process. SFR also have advantages of proliferation of nuclear fuel and burn long-lived radioactive nuclides. The closed fuel cycle formed by the development of fast reactors and pressurized water reactors can effectively achieve the sustainable development of nuclear energy. Hydrogen production could be considered in the design of the next generation million kilowatts-level fast reactor (CFR1000), making the hydrogen production process more economical and reduction of carbon emissions, simultaneously. Considering the reactor outlet temperature and the aim of zero-carbon emission during the hydrogen production process, the results reveal that the most suitable hydrogen production methods for SFR are the thermo-chemical cycle (copper-chlorine cycle) and conventional electrolysis. For conventional electrolysis, hydrogen production efficiency is relatively low, but the technology maturity is much higher compared with the other methods. For the thermo-chemical cycle (copper-chlorine cycle), technology maturity is relatively low but has higher hydrogen production efficiency, which could make the hydrogen production process more economical in the future. Based on the hydrogen economic evaluation program HEEP (V2021) which was developed by the IAEA, an economic study on the hydrogen production cost per kilograms of CFR1000 was conducted, which was verified by the fourth-generation reactor economic evaluation software G4-ECONS V3.0 developed by GIF. The cost of the hydrogen production by conventional electrolysis coupled with the CFR1000 is 3.05 / � � , � � � � ℎ � � � � � � � ℎ � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � ℎ � ℎ � � ℎ � � � � − � ℎ � � � � � � � � � � � � � 4.83 /kg. However, with the investment ratio reduction of SFR, and the potential impact of carbon sinks in the future, the cost of hydrogen production will be further explored. HEEP calculation results show that a decrease in the overnight investment of CFR1000 could significantly reduce the cost of hydrogen production. Overall, SFR shows great promise in the field of hydrogen production in the future.

Due to the directional nature of sp3-hybridized orbitals and the absence of π-orbitals, the oxidative cleavage of the kinetically and thermodynamically stable C(sp3)–C(sp3) bond is extremely difficult and remains scarcely explored. In this work, under the double argument of quantum mechanics (QM) computations and meticulous experiments on our well-designed C–C single bond cleavage mechanism, we discovered a means of photoinduced selective oxidative C(sp3)–C(sp3) bond cleavage in arylamines, easily achieved by simple visible light irradiation using O2 as a benign oxidant under very mild conditions. The utility of our methodology was demonstrated by the C(sp3)–C(sp3) bond cleavage in morpholine/piperazine arylamines with excellent functional group tolerance. Importantly, our methodology is noteworthy, not only in that it does not require any catalysts, but also in that it provides valuable possibilities for the scalable functionalization of clinical drugs and natural products. [ABSTRACT FROM AUTHOR]

Due to the particularity of the thiocarbonyl group (C＝S bond), only limited C(sp3)–H thiocarbonylation methods, especially efficient and convenient methods, have been developed for the synthesis of thioamides. Inspired by the "solvent-specificity-based" design strategy, we discovered a simple, practical and environmentally friendly C(sp3)–H thiocarbonylation of benzylamine substrates for facile thioamide synthesis under catalyst-free conditions. A diverse array of benzylamine derivatives were tolerated by this catalyst-free thiocarbonylation. Furthermore, the (QM) computations and well-designed experiments on the reaction mechanism revealed that this thiocarbonylation depends on the specific solvent that initially drives this reaction through the intermolecular hydrogen atom transfer (HAT). And the following single electron transfer (SET) induces the electron-catalyzed C–S bond formation and intramolecular HAT realizing the final establishment of the C＝S bond. [ABSTRACT FROM AUTHOR]

Objective: Esophageal fistula is a critical and fatal complication of esophageal cancer. The aim of this meta-analysis was to explore the risk factors for esophageal perforation in esophageal cancer patients treated with radiotherapy. Methods: Data from the PubMed and Embase databases were retrieved for clinical research published between 1990 and 2018. The Newcastle-Ottawa Scale was used to evaluate the quality of the articles. A meta-analysis was performed using the RevMan 5.3 software provided by the Cochrane Collaboration Network. Results: Seventeen articles were eligible for the meta-analysis. In these articles, over 35 risk factors for esophageal fistula formation were described and 17 risk factors were analyzed. Significant differences in the odds of developing an esophageal perforation were found with regard to age (OR 2.34, 95% CI 1.08–5.03, p = 0.001), ulcerative type (OR 2.72, 95% CI 1.43–5.16, p = 0.002), histology (OR 4.16, 95% CI 1.14–15.12, p = 0.03), T stage (OR 2.66, 95% CI 1.44–4.91, p = 0.002), short-term response (OR 2.21, 95% CI 1.06–4.62, p = 0.03), chemotherapy regimen (OR 2.80, 95% CI 1.38–5.68, p = 0.005), and stenosis (OR 2.00, 95% CI 1.03–3.89, p = 0.04). Conclusions: An age of <60–65 years, ulcerative type, squamous cell cancer, T4 stage, incomplete response, fluorouracil-based regimen, and stenosis were associated with an increased risk of esophageal fistula during or after radiotherapy. However, further, large-scale prospective studies are needed to establish the validity of this associ-ation. [ABSTRACT FROM AUTHOR]