Rational exploration of efficient, inexpensive, and robust electrocatalysts is critical for the efficient water splitting. Conjugated conductive metal–organic frameworks (cMOFs) with multicomponent ...layered double hydroxides (LDHs) to construct bifunctional heterostructure catalysts are considered as an efficient but complicated strategy. Here, the fabrication of a cMOF/LDH hetero‐nanotree array catalyst (CoNiRu‐NT) coupled with monodispersed ruthenium (Ru) sites via a controllable grafted‐growth strategy is reported. Rich‐amino hexaiminotriphenylene linkers coordinate with the LDH nanotrunk to form cMOF nanobranches, providing numerous anchoring sites to precisely confine and stabilize RuN4 sites. Moreover, monodispersed and reduced Ru moieties facilitate H2O adsorption and dissociation, and the heterointerface between the cMOF and the LDH further modifies the chemical and electronic structures. Optimized CoNiRu‐NT displays a significant increase in electrochemical water‐splitting properties in alkaline media, affording low overpotentials of 22 mV at 10 mA cm−2 and 255 mV at 20 mA cm−2 for the hydrogen evolution reaction and oxygen evolution reaction, respectively. In an actual electrochemical system, CoNiRu‐NT drives an overall water splitting at a low cell voltage of 1.47 V to reach 10 mA cm−2. This performance is comparable to that of pure noble‐metal‐based materials and superior to most reported MOF‐based catalysts.
A conductive metal–organic framework (cMOF)/layered double hydroxide (LDH) hetero‐nanotree structure coupled with monodisperse Ru sites is constructed via a controllable grafted‐growth strategy. Based on a competitive coordination process, RuN sites are precisely anchored by rich‐amino organic linkers. The chemical and electronic structure of the hetero‐nanotree catalysts are well modified and lead to a superior overall water‐splitting performance in alkaline media.
Under investigation in this paper is the coupled nonlinear Schrödinger system which describes the mode-locked fiber lasers. Based on the Hirota method and Kadomtsev–Petviashvili hierarchy reduction ...method, N-dark–dark soliton solutions are derived. Features and asymptotic behaviors of dark–dark solitons are analyzed in detail, and typical dynamics has been demonstrated. Both proportional and not proportional single dark–dark solitons in u and v components are studied. Interactions of two dark–dark solitons are demonstrated. We find that there is no energy transfer between the two solitons or between the u and v components before and after the interactions.
Highly efficient and stable catalysts for the hydrogen evolution reaction, especially in alkaline conditions are crucial for the practical demands of electrochemical water splitting. Here, the ...synthesis of a novel RuAu single‐atom alloy (SAA) by laser ablation in liquid is reported. The SAA exhibits a high stability and a low overpotential, 24 mV@10 mA cm−2, which is much lower than that of a Pt/C catalyst (46 mV) in alkaline media. Moreover, the turnover frequency of RuAu SAA is three times that of Pt/C catalyst. Density functional theory computation indicates the excellent catalytic activity of RuAu SAAs originates from the relay catalysis of Ru and Au active sites. This work opens a new avenue toward high‐performance SAAs via fast quenching of immiscible metals.
A RuAu single‐atom alloy (SAA) is achieved by laser ablation in liquid. RuAu SAA exhibits high performance in the hydrogen evolution reaction through the relay catalysis of the Ru host (for water dissociation) and the Au dopant (for hydrogen evolution).
Eculizumab, a monoclonal antibody (mAb) directed against complement protein C5, is considered to be the current standard of care for patients with paroxysmal nocturnal hemoglobinuria (PNH) and ...atypical hemolytic uremic syndrome. This study describes the generation and preclinical attributes of ALXN1210, a new long-acting anti-C5 mAb, obtained through select modifications to eculizumab to both largely abolish target-mediated drug disposition (TMDD) and increase recycling efficiency via the neonatal Fc receptor (FcRn). To attenuate the effect of TMDD on plasma terminal half-life (t1/2), histidine substitutions were engineered into the complementarity-determining regions of eculizumab to enhance the dissociation rate of the mAb:C5 complex in the acidic early endosome relative to the slightly basic pH of blood. Antibody variants with optimal pH-dependent binding to C5 exhibited little to no TMDD in mice in the presence of human C5. To further enhance the efficiency of FcRn-mediated recycling of the antibody, two additional substitutions were introduced to increase affinity for human FcRn. These substitutions yielded an additional doubling of the t½ of surrogate anti-mouse C5 antibodies with reduced TMDD in transgenic mice expressing the human FcRn. In conclusion, ALXN1210 is a promising new therapeutic candidate currently in clinical development for treatment of patients with PNH and atypical hemolytic uremic syndrome.
In crop plants, a high-density genetic linkage map is essential for both genetic and genomic researches. The complexity and the large size of wheat genome have hampered the acquisition of a ...high-resolution genetic map. In this study, we report a high-density genetic map based on an individual mapping population using the Affymetrix Wheat660K single-nucleotide polymorphism (SNP) array as a probe in hexaploid wheat. The resultant genetic map consisted of 119 566 loci spanning 4424.4 cM, and 119 001 of those loci were SNP markers. This genetic map showed good collinearity with the 90 K and 820 K consensus genetic maps and was also in accordance with the recently released wheat whole genome assembly. The high-density wheat genetic map will provide a major resource for future genetic and genomic research in wheat. Moreover, a comparative genomics analysis among gramineous plant genomes was conducted based on the high-density wheat genetic map, providing an overview of the structural relationships among theses gramineous plant genomes. A major stable quantitative trait locus (QTL) for kernel number per spike was characterized, providing a solid foundation for the future high-resolution mapping and map-based cloning of the targeted QTL.
Magnetoelectric materials with a large magnetoelectric response, a low operating magnetic (or electric) field, and a room‐temperature (or higher) operating temperature are of key importance for ...practical applications. However, such materials are extremely rare because a large magnetoelectric response often requires strong coupling between spins and electric dipoles. Herein, an example of a magnetoelectric composite is prepared by using a room‐temperature multiaxial molecular–ionic ferroelectric, tetramethylammonium tetrachlorogallate(III) (1). Investigation of the magnetoelectric effect of the magnetoelectric laminate composite indicates that its room‐temperature magnetoelectric voltage coefficient (αME) is as high as 186 mV cm−1 Oe−1 at HDC = 275 Oe and at the HAC frequency of ≈39 kHz, providing a valid approach for the preparation of magnetoelectric materials and adding a new member to the magnetoelectric material family.
A magnetoelectric composite is prepared by using a room‐temperature multiaxial molecular–ionic tetramethylammonium tetrachlorogallate(III) ferroelectric. The room‐temperature magnetoelectric voltage coefficient is up to 186 mV cm−1 Oe−1 at HDC = 275 Oe and the HAC frequency is ≈39 kHz. This work demonstrates that multiaxial molecular–ionic ferroelectrics are new excellent candidates for the preparation of magnetoelectric composites.
MicroRNAs (miRNAs) play important roles in rice response to Magnaporthe oryzae, the causative agent of rice blast disease. Studying the roles of rice miRNAs is of great significance for the disease ...control. Osa‐miR167d belongs to a conserved miRNA family targeting auxin responsive factor (ARF) genes that act in developmental and stress‐induced responses. Here, we show that Osa‐miR167d plays a negative role in rice immunity against M. oryzae by suppressing its target gene. The expression of Osa‐miR167d was significantly suppressed in a resistant accession at and after 24 h post inoculation (hpi), however, its expression was significantly increased at 24 hpi in the susceptible accession upon M. oryzae infection. Transgenic rice lines over‐expressing Osa‐miR167d were highly susceptible to multiple blast fungal strains. By contrast, transgenic lines expressing a target mimicry to block Osa‐miR167d enhanced resistance to rice blast disease. In addition, knocking out the target gene ARF12 led to hyper‐susceptibility to multiple blast fungal strains. Taken together, our results indicate that Osa‐miR167d negatively regulate rice immunity to facilitate the infection of M. oryzae by downregulating ARF12. Thus, Osa‐miR167d‐ARF12 regulatory module could be valuable in improvement of blast‐disease resistance.
Rice blast caused by Magnaporthe oryzae is one of the most destructive diseases. Here we demonstrated that rice Osa‐miR167d facilitates the infection of M. oryzae by suppressing ARF12, and ARF12 is required for resistance to the blast disease. Our findings suggest that the Osa‐miR167d‐ARF12 regulatory module is valuable in blast‐disease breeding programs.
The electrochemical method of combining N2 and H2O to produce ammonia (i.e., the electrochemical nitrogen reduction reaction E‐NRR) continues to draw attention as it is both environmentally friendly ...and well suited for a progressively distributed farm economy. Despite the multitude of recent works on the E‐NRR, further progress in this field faces a bottleneck. On the one hand, despite the extensive exploration and trial‐and‐error evaluation of E‐NRR catalysts, no study has stood out to become the stage protagonist. On the other hand, the current level of ammonia production (microgram‐scale) is an almost insurmountable obstacle for its qualitative and quantitative determination, hindering the discrimination between true activity and contamination. Herein i) the popular theory and mechanism of the NRR are introduced; ii) a comprehensive summary of the recent progress in the field of the E‐NRR and related catalysts is provided; iii) the operational procedures of the E‐NRR are addressed, including the acquisition of key metrics, the challenges faced, and the most suitable solutions; iv) the guiding principles and standardized recommendations for the E‐NRR are emphasized and future research directions and prospects are provided.
Ammonia represents the blood of industry; and agriculture, crop growth, green energy fuels, and industry production are inseparable from it. The electrochemical synthesis of ammonia is expected to replace the harsh and environmentally unfriendly Harber–Bosch process. A timely and comprehensive review of the booming ambient electrochemical ammonia synthesis is presented to promote its rapid and healthy development.
Rationally optimizing the photoluminescence performance via accurate structural modulation is one of most important and challenging issues for hybrid halides. Herein, a viable crystal dimensional ...reduction strategy is proposed to reasonably enhance the photoluminescence quantum yield (PLQY) of hybrid antimony halide. Specifically, a synthetic technique is developed and new 1D DMPZSbCl5 ∙ H2O (DP‐SbCl5) is sliced to 0D DMPZ2SbCl6 ∙ Cl ∙ (H2O)2 (DP‐SbCl6) with crystal dimensional reduction from infinite SbCl52− chain to discrete SbCl63− octahedron. Comparing with nonluminescent 1D DP‐SbCl5, 0D DP‐SbCl6 displays highly efficient broadband yellow light emission with enhanced PLQY up to 75.94%. First‐principles calculation demonstrates that 0D DP‐SbCl6 features more flat and narrow band structure, which promotes the photoelectron localization and increases the quantum confinement, and finally boosts the luminescence efficiency. Together highly efficient and ultra‐stable luminescence performance enable DP‐SbCl6 as excellent down‐conversion broadband yellow phosphor to successfully fabricate white light emitting diodes with a high color rendering index of 92. This work provides a novel structural modulation strategy of crystal dimensional reduction to rationally optimize the PL performance of hybrid metal halides.
With controllable structural evolution from 1D to 0D hybrid antimony halides, the photoluminescence quantum yield (PLQY) realizes a notable enhancement from <1% to 75.94% in yellow spectral region benefitting from more localized photoelectrons and increased quantum confinement. This work provides a structural platform to verify the feasibility of crystal dimensionality reduction strategy to rationally improve the PLQY of metal halides.
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