Developing low‐cost and high‐activity pH‐universal hydrogen evolution reaction (HER) catalysts is very crucial to the industrialization of water electrolysis. However, the high price, low yield, and ...poor stability of current HER catalysts make them difficult to meet practical requirements. Herein, a plasma spraying technique is employed to prepare self‐supported Cu catalysts with tensile strain for the first time. The tensile strain upshifts the d‐band of Cu, improves the water dissociation and H* adsorption, eventually improves the intrinsic HER catalytic activity. As such, Cu electrode achieves overpotentials of 182 mV in 0.5 m H2SO4, 261 mV in 1 M PBS, and 121 mV in 1 M KOH at 10 mA cm–2. In addition, Cu electrode also performs well at high current densities, the overpotentials at 1 A cm–2 are much lower than those of Pt foil in acid, neutral, and alkaline solutions.
The Cu electrode prepared by plasma spraying exhibits an excellent pH‐universal HER catalytic activity, superb long‐term stability, and marvelous corrosion resistance. The superb HER activity is attributed to self‐supported porous structure, abundant active sites, tensile strain enhanced intrinsic catalytic activity, and small charge transfer resistance.
As a metal-free photocatalyst, graphitic carbon nitride (g-CN) shows great potential for photocatalytic water splitting, although its performance is significantly limited by structural defects due to ...incomplete polymerization. In the present work, we successfully synthesize highly conjugated g-CN nanofoam through an iodide substitution technique. The product possesses a high polymerization degree, low defect density, and large specific surface area; as a result, it achieves a hydrogen evolution rate of 9.06 mmol h–1 g–1 under visible light irradiation, with an apparent quantum efficiency (AQE) of 18.9% at 420 nm. Experimental analysis and theoretical calculations demonstrate that the recombination of photogenerated carriers at C–NH x defects was effectively depressed in the nanofoam, giving rise to the high photocatalytic activity.
Developing highly active and low-cost catalysts for the oxygen reduction reaction (ORR) is critical for renewable energy devices such as metal–air cells and fuel cells. In this work, we report an ...active ORR catalyst, Ag clusters with adatoms, which can be facilely produced by a pulse electrolysis method. The silver adatom on the silver cluster can reduce the coordination number, upshift the Ag d-band center, lower the ORR reaction barrier, and eventually transform the inactive Ag into a highly active catalyst. As a result, the catalyst exhibits high activity and stability, which are superior to ever-reported silver-based catalysts and even the commercial Pt/C catalyst.
The development of low-cost, high-activity, and pH universal catalysts is essential in hydrogen evolution reaction (HER) via industrial electrolysis of water. Here, we report the rapid and scalable ...preparation of defect-rich copper catalysts as electrocatalysts for all-pH HER by electric discharge in liquid (EDL) technology. The defects upshift the d-band center of copper, improve water dissociation and hydrogen adsorption, and ultimately improve the intrinsic catalytic activity. Thus, the overpotentials of Cu catalysts reach 180 mV in 0.5 M H2SO4, 269 mV in 1 M PBS, and 152 mV at 10 m A cm–2 in 1 M KOH. In addition, the Cu catalysts also exhibit lower overpotentials at high current density (1 A cm–2), superior to commercial Pt/C in neutral and alkaline solutions. Our work demonstrates that the EDL is a powerful technique for preparing metallic catalyst, and introducing defects into copper nanoparticles provides a versatile and friendly strategy for improving intrinsic catalytic performance.
Bismuth porous nanosheets (Bi PNSs) were synthesized via a three-step process in the absence of any surfactants and templates. As a catalyst for electrochemical CO2 electroreduction, Bi PNSs show ...high selectivity to formic acid with the maximum Faraday efficiency of 95.31% and maintain more than 80% Faraday efficiency over a wide voltage range of 1100 mV. The excellent performance of Bi PNSs was found to originate from the abundant kink sites on the pore walls, which have appropriate affinity to intermediates and reduce the energy barriers for CO2 electroreduction. Our work demonstrates that a clean synthetic route is advantageous to the growth of a unique nanostructure that possesses high catalytic activity.
Jojoba（Simmondsia chinensis） is mainly distributed in desert,and the molecular mechanisms of jojoba in response to abiotic stress still remain elusive.In this paper,we cloned and characterized a SOD ...gene from jojoba named as ScMnSOD,and introduced into Arabidopsis to investigate its functions of responding to drought stress.The transgenic Arabidopsis showed an improvement in drought tolerance.Moreover,under a water deficit condition,the accumulation of reactive oxygen species（ROS） was remarkably decreased in the transgenic lines compared to the WT.Furthermore,the ScMnSOD promoter was cloned to the 5′-upstream of GUS coding region in a binary vector,and introduced into Arabidopsis.And results showed that ScMnSOD expression can be induced by drought,salt,ABA,and low temperature.In conclusion,ScMnSOD plays an important role in drought tolerance which is,at least partially,attributed to its role in ROS detoxification.
The long-term goal of artificial intelligence （AI） is to make machines learn and think like human beings. Due to the high levels of uncertainty and vulnerability in human life and the open-ended ...nature of problems that humans are facing, no matter how intelligent machines are, they are unable to completely replace humans. Therefore, it is necessary to introduce human cognitive capabilities or human-like cognitive models into AI systems to develop a new form of AI, that is, hybrid-augmented intelligence. This form of AI or machine intelligence is a feasible and important developing model. Hybrid-augmented intelligence can be divided into two basic models： one is human-in-the-loop augmented intelligence with human-computer collaboration, and the other is cognitive computing based augmented intelligence, in which a cognitive model is embedded in the machine learning system. This survey describes a basic framework for human-computer collaborative hybrid-augmented intelligence, and the basic elements of hybrid-augmented intelligence based on cognitive computing. These elements include intuitive reasoning, causal models, evolution of memory and knowledge, especially the role and basic principles of intuitive reasoning for complex problem solving, and the cognitive learning framework for visual scene understanding based on memory and reasoning. Several typical applications of hybrid-augmented intelligence in related fields are given.
Background There are no data on more tolerable capecitabine doses in elderly patients in Chinese population. The aim of this study was to evaluate the activity and safety of capecitabine combined ...with weekly docetaxel for the treatment of anthracycline-resistant metastatic breast cancer （MBC） in older Chinese patients. Methods MBC patients aged 〉65 years pretreated with 1-5 prior chemotherapy regimens, including an anthracycline, received oral capecitabine 825 mg/m^2 twice daily, days 1-14, plus docetaxel 30 mg/m^2 on days 1 and 8 every 21 days. All 41 enrolled patients received at least 1 dose of treatment and were evaluable for safety; 38 received at least 2 cycles （median 4, range 2-8） and were evaluable for efficacy. Results The overall objective response rate was 47%, including complete responses in 8% of patients. Median time to progression was 8.9 months. Median overall survival was 17.6 months. The most common side effects were haematological and gastrointestinal toxicities and hand-foot syndrome. The only grade 3/4 adverse events were neutropenia （12%）, alopecia （7%）, grade 3 nausea and vomiting （2%） and grade 3 nail toxicity （2%）. Conclusions Capecitabine 825 mg/m^2 twice daily plus weekly docetaxel is active with an acceptable safety profile in Chinese women 〉65 years with anthracycline-resistant MBC. Efficacy and tolerability compare favourably with previously reported trials evaluating higher capecitabine doses in combination with 3-weekly or weekly docetaxel.
C-C motif ligand 2 (CCL2), also known as monocytic chemotactic protein 1 (MCP-1), is an integral chemotactic factor which recruits macrophages for the immune response. Together with its receptors ...(e.g., CCR2, ACKR1, and ACKR2), they exert noticeable influences on various diseases of different systems. At the maternal-fetal interface, CCL2 is detected to be expressed in trophoblasts, decidual tissue, the myometrium, and others. Meanwhile, existing reports have determined a series of physiological regulators of CCL2, which functions in maintaining normal recruitment of immunocytes, tissue remodeling, and angiogenesis. However, abnormal levels of CCL2 have also been reported to be associated with adverse pregnancy outcomes such as spontaneous abortion, preeclampsia and preterm labor. In this review, we concentrate on CCL2 expression at the maternal-fetal interface, as well as its precise regulatory mechanisms and classic signaling pathways, to reveal the multidimensional aspects of CCL2 in pregnancy.
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