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Cobalt phosphosulphide (CoPS) has recently been recognized as a potentially effective electrocatalyst for the hydrogen evolution reaction (HER). However, there have been no research on the design of CoPS‐based heterojunctions to boost their HER performance. Herein, CoPS/Co4S3 heterojunction was prepared by phosphating treatment based on defect‐rich flower‐like Co1‐xS precursors. The high specific surface area of nanopetals, together with the heterojunction structure with inhomogeneous strain, exposes more active sites in the catalyst. The electronic structure of the catalyst is reconfigured as a result of the interfacial interactions, which promote the catalyst's ability to adsorb hydrogen and conduct electricity. The synergistic effect of the Co and S dual‐site further enhance the catalytic activity. The catalyst has overpotentials of 61 and 70 mV to attain a current density of 10 mA cm−2 in acidic and alkaline media, respectively, which renders it competitive with previously reported analogous catalysts. This work proposes an effective technique for constructing transition metal phosphosulfide heterojunctions, as well as the development of an efficient HER electrocatalyst. [ABSTRACT FROM AUTHOR]

The rock's mechanical properties play an important role in the whole process of conventional and unconventional oil and gas exploration and progression. At present, there are two approaches to determining the mechanical parameters. One is to measure the rock sample in the laboratory (i.e., static elastic modulus Es). The other is to obtain parameters by geophysical logging data (i.e., dynamic elastic modulus Ed). In general, static parameters can more accurately reflect the mechanical properties of rock under actual geo-stresses. At the same time, their determinations are difficult. Therefore, one of the best methods is to establish the correlation between the dynamic and static parameters. This paper investigates the relation between the dynamic and static parameters using different methods for various rocks in the literature. Based on the relationship of  E s = a E d + b , a correction between a and b is proposed using the multinomial form  a = 0.67 + 0.101 b − 0.006 b 2 + 0.0001 b 3 . It is found that the Es can be derived from the Ed just when the parameter b is known. In terms of different types of rocks, for igneous and metamorphic rocks, the best correlation between Es and Ed obeys the power-law correlation; for sedimentary rocks, there are linear and logarithmic correlations. Theoretically, the difference between dynamic and static elastic moduli can be attributed to microcracks and pores within rocks. This study can provide guidance for engineers to predict the desired static parameters precisely using logging or seismic data. [ABSTRACT FROM AUTHOR]

The exploration of new heterojunction materials is of great significance in reducing the cost of existing noble metal catalysts and thus realizing the large-scale application of electrocatalytic hydrolysis technology. Herein, a novel CoP/CoMoP2 heterojunction was synthesized and served as a hydrogen evolution reaction (HER) electrocatalyst. The heterojunction has morphology of nanoporous structure, which is conducive to exposing more active sites and facilitating bubbles transport. The charge distribution is optimized by a strong interface interaction between CoP and CoMoP2. The catalyst's conductivity and the adsorption properties of the intermediates have both been enhanced. CoP/CoMoP2 demonstrates excellent HER activity with an overpotential of 93.6 mV at 10 mA·cm−2, which is competitive with the reported performance of analogous electrocatalysts. This work provides insights into the development of innovative phosphide-based heterojunction electrocatalysts. [ABSTRACT FROM AUTHOR]

The fabrication of heterojunctions is an intriguing approach to boost the reactivity of catalysts. However, facile preparation of desirable heterojunction materials remains a challenge. Here, novel CoPS3/CoS2 heterojunctions are created by an intuitive phosphatization process on the basis of structurally flexible cobalt sulfide precursors. Significant stress effect exists at these heterogeneous interfaces, resulting in lattice distortions and the exposure of more active sites. The interface interaction also modifies the catalyst's electronic structure to improve its electrical conductivity and hydrogen adsorption capabilities. Notably, the overpotential of the CoPS3/CoS2 heterojunction for electrocatalytic hydrogen evolution reaction is just 36.3 mV, which is far superior to those of single‐component catalysts and competitive with comparable catalysts reported. This work not only offers an innovative electrocatalyst but also a strategy that can be used to create heterojunctions based on related transition metal thiophosphates. [ABSTRACT FROM AUTHOR]

Despite the fact that d‐band center theory links the d electron structure of transition metals to their catalytic activity, it is yet unknown how the synergistic effect of multi‐d electrons impacts catalytic performance. Herein, novel LaNi1‐xCoxRu intermetallics containing 5d, 4d, and 3d electrons were prepared. In these compounds, the 5d orbital of La transfers electrons to the 4d orbital of Ru, which provides adsorption sites for H*. The 3d orbitals of Ni and Co interact with the 5d and 4d orbitals to generate an anisotropic electron distribution, which facilitates the adsorption and desorption of OH*. The synergistic effect of multi‐d electrons ensures efficient catalytic activity. The optimized LaNi0.5Co0.5Ru has an overpotential of 43mV at 10 mA cm−2 for alkaline electrocatalytic hydrogen evolution reaction. Beyond offering a variety of new electrocatalysts, this work reveals the multi‐d electron synergy in promoting catalytic reaction. [ABSTRACT FROM AUTHOR]

The hydrogen spillover effect has garnered considerable attention as a promising avenue to enhance the activity of the hydrogen evolution reaction (HER) in metal‐support compound materials. Herein, Pt atom dimers on the NiOOH support are successfully synthesized with a reversed hydrogen spillover effect, demonstrating much better alkaline HER activity than Pt single atoms and Pt clusters. Atomic and electronic structure characterizations unequivocally verify the anchoring of Pt atom dimers on NiOOH through Pt─O bonds, thus obtaining a reversed and enhanced hydrogen spillover effect. Theoretical and experimental results indicate that NiOOH exhibits pronounced water dissociation capability, while the Pt atom dimers, in comparison to Pt single atoms and Pt clusters, demonstrate superior hydrogen desorption ability. The reversed spillover with Pt atom dimers leads to remarkable HER activity in alkaline solutions, as evidenced by an ultra‐small overpotential of 13 mV at 10 mA cm−2. These findings not only provide insights into the potential use of atom dimers for HER, but also shed light on reversed spillover in designing high‐performance catalysts. [ABSTRACT FROM AUTHOR]

The electrocatalytic hydrogen evolution activity of transition metal sulfide heterojunctions are significantly increased when compared with that of a single component, but the mechanism behind the performance enhancement and the preparation of catalysts with specific morphologies still need to be explored. Here, we prepared a Co9S8/MoS2 heterojunction with microsphere morphology consisting of thin nanosheets using a facile two-step method. There is electron transfer between the Co9S8 and MoS2 of the heterojunction, thus realizing the redistribution of charge. After the formation of the heterojunction, the density of states near the Fermi surface increases, the d-band center of the transition metal moves downward, and the adsorption of both water molecules and hydrogen by the catalyst are optimized. As a result, the overpotential of Co9S8/MoS2 is superior to that of most relevant electrocatalysts reported in the literature. This work provides insight into the synergistic mechanisms of heterojunctions and their morphological regulation. [ABSTRACT FROM AUTHOR]

Molybdenum diselenide and cobalt diselenide have been commonly implemented in electrocatalytic hydrogen evolution reaction (HER). However, there have been few research on the creation of their three‐phase heterojunctions and the associated HER process. Herein, we constructed a three‐phase heterostructure sample consisting of orthorhombic CoSe2, cubic CoSe2 and MoSe2 and we investigated its HER performance. The sample shows microsphere morphology composed of nanosheets with interfacial interactions between the components. It possesses an overpotential of −136 mV at −10 mA cm−2 in acid medium, which is superior to that of single component and most two‐phase heterostructures. Especially, the overpotential at −200 mA cm−2 is smaller than that of Pt/C. The excellent performance can be attributed to the d‐orbital upshift of the Co active sites due to charge redistribution between the three‐phase heterojunction and the optimization of the hydrogen free energy. This work provides inspiration for exploring the application of other multi‐component heterojunctions in electrocatalytic hydrogen evolution. [ABSTRACT FROM AUTHOR]

High temperature is a major stress in rice production. Although considerable progress has been made in investigating heat tolerance (HT) in rice, the genetic basis of HT at the heading stage remains largely unknown. In this study, a novel set of chromosome segment substitution lines (CSSLs) consisting of 113 lines derived from a heat-resistant indica variety N22 and a heat-sensitive indica variety 9311 was developed and used for the analysis of the genetic basis of HT. The heat sensitivity index (HSI) calculated based on seed-setting rates under natural and high-temperature environments was used to evaluate the influence of HT at the rice heading stage. In total, five quantitative trait loci (QTLs) associated with HT were detected based on seed-setting rate (SSR) evaluation; these were named qSSR6-1, qSSR7-1, qSSR8-1, qSSR9-1 and qSSR11-1 located on chromosomes 6, 7, 8, 9 and 11, respectively. Heat-tolerant alleles of the QTLs were all derived from N22. Among them, qSSR9-1 overlapped with QTLs identified previously, while the remaining QTLs were found novel. In particular, qSSR7-1 explained a high phenotypic variation of 26.35% with a LOD score of 10.75, thus deserved to be further validated. These findings will increase our understanding of the genetic mechanism underlying HT and facilitate the breeding of heat-tolerant rice varieties. [ABSTRACT FROM AUTHOR]

NiFe-based electrode materials have been reported as a promising candidate for the oxygen evolution reaction (OER). However, fabrication of such electrode materials with both high catalytic activity and long-term stability remains challenging. Herein, we developed an in situ self-corrosion photodeposition method to synthesize a self-standing hollow Fe–NiOHx catalyst on photoactive ZnO nanorods. The stable phase of the catalyst and the excellent adhesion interaction with the substrate brings excellent electrochemical stability. The synergetic effect between Ni and Fe atoms significantly enhances the adsorption of the OH group and facilitates the removal of the surface H atom, leading to lower overpotential. As a result, the as-fabricated catalyst exhibits excellent OER activity and remarkable stability at a high current density, which only requires an overpotential of 210 mV at a current density of 10 mA cm−2 and shows no significant degradation after a 240-h durability test at a high current density of 100 mA cm−2. This research work provides an alternative approach for the rational design of desirable electrocatalysts with high activity and long-term stability. [ABSTRACT FROM AUTHOR]

The construction of heterostructures is a versatile tactic to enhance catalytic activity. However, it is still elusive to realize the modulation of the interlayer spacing in this way to further improve the performance. Here, strong interfacial coupling between CoSe2 and MoSe2 by constructing CoSe2/MoSe2 heterostructures is achieved. The interlayer spacing of MoSe2 is compressed by 0.3 Å. The enhanced charge transfer is validated by X‐ray absorption spectroscopy and X‐ray photoelectron spectroscopy. Coupled with the morphology of hollow microtubes, which can facilitate the exposure of active sites, CoSe2/MoSe2 heterostructures reported here exhibit high activity (119 mV at 10 mA cm−2) and excellent stability with small degradation after 50 h operation, surpassing other analogous powdered electrocatalysts. This work sheds light on the importance of tuning the interlayer spacing to improve electrocatalytic activity. [ABSTRACT FROM AUTHOR]

The discovery and identification of novel active sites are paramount for deepening the understanding of the catalytic mechanism and driving the development of remarkable electrocatalysts. Here, we reveal that the genuine active sites for the hydrogen evolution reaction (HER) in LaRuSi are Si sites, not the usually assumed Ru sites. Ru in LaRuSi has a peculiar negative valence state, which leads to strong hydrogen binding to Ru sites. Surprisingly, the Si sites have a Gibbs free energy of hydrogen adsorption that is near zero (0.063 eV). The moderate adsorption of hydrogen on Si sites during the HER process is also validated by in situ Raman analysis. Based on it, LaRuSi exhibits an overpotential of 72 mV at 10 mA cm−2 in alkaline media, which is close to the benchmark of Pt/C. This work sheds light on the recognition of real active sites and the exploration of innovative silicide HER electrocatalysts. [ABSTRACT FROM AUTHOR]

Sluggish electron kinetics in the oxygen evolution reaction (OER) is one of the main factors restricting the development of hydrogen production technology from electrical water splitting, while the key to breaking through the bottleneck is to develop low-cost and efficient OER electrocatalysts. Here, a scheme for regulating the phase of electrocatalysts using carbon nanotubes is proposed, which significantly boosts the OER activity of transition metal complexes, exhibiting comparable electrocatalytic performance to noble metals. In this process, an organic complex of cobalt was combined with carbon nanotubes that prevent the catalyst from crystallizing during vulcanization, with sulfur atoms replacing some of oxygen atoms to further modify the active center. The as-fabricated amorphous CoOxSy complex showed excellent OER activity with a unique electronic structure, resulting in overpotentials of 290 mV and 330 mV at current densities of 10 mA cm−2 and 100 mA cm−2, respectively, and a Tafel slope of 50.8 mV dec−1. Moreover, the participation of carbon nanotubes further enhanced the electrochemical stability of the catalyst, which exhibited consistent performance in stability tests up to 60 hours. The results demonstrate the potential of carbon-based amorphous transition metal complexes as highly active electrocatalysts and provide a new possibility to design efficient catalysts by phase engineering. [ABSTRACT FROM AUTHOR]

Alloying noble metals with non‐noble metals is a promising method to fabricate catalysts, with the advantages of reduced noble metal usage and excellent activity. In this work, electron‐abundant Ir/Rh sites, as highly active centers for the hydrogen evolution reaction (HER), are realized by fabricating Ir1−xRhxSb alloys through the arc‐melting method. The electron transfer from Sb to Ir/Rh makes the latter negatively charged, leading to considerably optimized adsorption for active H species during HER. As a result, the Ir1−xRhxSb alloy exhibits outstanding activity for HER, with an optimized overpotential of 22 mV at 10 mA cm–2 and a Tafel slope of 47.6 mV dec–1. This work provides insights into highly active alloys and sheds light on the utilization of electron‐abundant metal atoms. [ABSTRACT FROM AUTHOR]

The separate modulation of the adsorption of *O and *OOH is challenging in oxygen evolution reaction (OER), which results in a large overpotential and slow kinetics. To balance the adsorption of the two active species, here, a way to regulate the local spin state and band structure simultaneously in Ni3S2 nanosheets is reported. The adequate doping of W heteroatoms causes the electron depletion from the Ni active site, which modulates the spin state of eg electrons, weakening the adsorption of *O. Additionally, the introduction of S vacancies contributes to the upshift of the d band center, which strengthens the adsorption of *OOH. In this manner, the adsorption of Ni3S2 for the active intermediates is optimized, resulting in a considerably improved overpotential of 246 mV at 100 mA cm−2 and a Tafel slope of 66 mV dec−1. This work provides insights into the exploration of OER catalysts through synergistic modulation of the spin state and the band structure. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) is the world's most prevalently infectious disease. Molecular mechanisms behind tuberculosis remain unknown. microRNA (miRNA) is involved in a wide variety of diseases. To validate the significant genes and miRNAs in the current sample, two messenger RNA (mRNA) expression profile datasets and three miRNA expression profile datasets were downloaded from the Gene Expression Omnibus (GEO) database. The differentially expressed (DE) genes (DEGs) and miRNAs (DE miRNAs) between healthy and TB patients were filtered out. Enrichment analysis was executed, and a protein-protein interaction (PPI) network was developed to understand the enrich pathways and hub genes of TB. Additionally, the target genes of miRNA were predicted and overlapping target genes were identified. We studied a total of 181 DEGs (135 downregulated and 46 upregulated genes) and two DE miRNAs (2 downregulated miRNAs) from two gene profile datasets and three miRNA profile datasets, respectively. 10 hub genes were defined based on high degree of connectivity. A PPI network's top module was constructed. The 23 DEGs identified have a significant relationship with miRNAs. 25 critically significant Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were discovered. The detailed study revealed that, in tuberculosis, the DE miRNA and DEGs form an interaction network. The identification of novel target genes and main pathways would aid with our understanding of miRNA's function in tuberculosis progression. [ABSTRACT FROM AUTHOR]

The coordination environment is crucial for the activity of an electrocatalyst, which defines the interaction between the central and adjacent atoms. In traditional 2D MX2 (M = Mo, W, etc., X = S, Se), M is usually coordinated with 6 X atoms in either trigonal prismatic (2H) or octahedral (1T) polyhedrons. With such a coordination configuration, only the edge X sites exhibit activity for hydrogen evolution reaction (HER). Here, a planar‐coordination transition metal chalcogenide, PdSe2 is reported, as an efficient electrocatalyst for the HER in an alkaline electrolyte. By reducing the spatial polyhedron coordination to planar polygon coordination, the M sites in PdSe2 can be efficiently activated to interact with the adsorptive intermediates. As a result, both Pd and Se atoms act as active sites for hydrogen evolution with neutral adsorption ability. With an overpotential of 138 mV at 10 mA cm−2, this work advances the exploration of planar‐coordination HER electrocatalysts. [ABSTRACT FROM AUTHOR]

Comprehensive characterization of traditional Chinese medicine prescriptions has long been a hurdle due to the chemical complexity and the lack of analytical tools. Mahuang decoction is a well‐known traditional Chinese medicine prescription widely used for sweating and relieving the exterior, relieving cough and asthma, but it was insufficiently chemically scrutinized. In this study, the chemical component information of Mahuang decoction was investigated by ultrahigh‐performance liquid chromatography tandem linear ion trap‐Orbitrap mass spectrometry. A new data processing tool, feature‐based molecular networking, was introduced for grouping and elucidating the compounds. In this way, 156 chemical components were identified or tentatively characterized, including alkaloids, triterpenoid saponins, flavanone‐O‐glycosides, flavone‐C‐glycosides, and procyanidins. Thus, this research provides a solid foundation for further development of Mahuang decoction, and the adopted method is expected to be applied to other traditional Chinese medicine prescriptions. [ABSTRACT FROM AUTHOR]

Optimizing the hydrogen adsorption Gibbs free energy (ΔGH) of active sites is essential to improve the overpotential of the electrocatalytic hydrogen evolution reaction (HER). We doped graphene‐like Co0.85Se with sulfur and found that the active sites are reversed (from cationic Co sites to anionic S sites), which contributed to an enhancement in electrocatalytic HER performance. The optimal S‐doped Co0.85Se composite has an overpotential of 108 mV (at 10 mA cm−2) and a Tafel slope of 59 mV dec−1, which exceeds other reported Co0.85Se‐based electrocatalysts. The doped S sites have much higher activity than the Co sites, with a hydrogen adsorption Gibbs free energy (ΔGH) close to zero (0.067 eV), which reduces the reaction barrier for hydrogen production. This work provides inspiration for optimizing the intrinsic HER activity of other related transition metal chalcogenides. [ABSTRACT FROM AUTHOR]

Significant efforts have been dedicated to boosting the electrocatalytic activity of Co9S8 for the oxygen evolution reaction (OER); however, with limited improvement in its intrinsic activity, which relies on careful band engineering. Fe possesses one less 3d electron and lower electronegativity than Co, suggesting a higher d‐band center when forming polyhedron with S anions. Here, to improve the intrinsic activity by elevating the d‐band center, the six‐coordinated octahedrons in Co9S8 are redesigned utilizing an Fe‐incorporated topochemical deintercalation method. Through substituting partial Co octahedrons by Fe octahedrons with higher d‐band, the overall d‐band center is regulated to achieve optimized adsorption and thus superior OER activity. With a reduction of 95 mV on the overpotential (at 10 mA cm−2), this work sheds lights on the design of OER catalysts through polyhedron engineering using topochemical deintercalation. [ABSTRACT FROM AUTHOR]

A new porous material, alveolate Cu2−xSe microsheets, was synthesized through a simple one-step solvothermal process. The surface morphology and microstructure of the as-prepared Cu2−xSe were characterized by various techniques. It was found that the as-synthesized Cu2−xSe has hierarchical porosity composed of mesopores and macropores, and rich active surfaces of {111} facets. A noteworthy visible-light-responsive photocatalytic discoloration of Rhodamine B was observed for the as-developed alveolate Cu2−xSe microsheets. The superior photocatalytic properties demonstrated by the as-synthesized Cu2−xSe are mainly attributed to the highly accessible active surfaces of the {111} facets and the wider light absorption range resulting from its narrower band gap. [ABSTRACT FROM AUTHOR]

We report the structure and physical properties of two quasi-two-dimensional triangular antiferromagnetic materials, Co0.66Al2Se3.53 and Ni0.61Al2Se3.55, which show highly magnetically frustrated characters. Powder X-ray diffractions demonstrate that Co0.66Al2Se3.53 and Ni0.61Al2Se3.55 possess identical space group of P -3 m 1 with lattice parameters a = 3.8089(1) Å, c = 12.676(1) Å and a = 3.7880(1) Å, c = 12.650(1) Å, respectively. Analyzing the susceptibility data of Co0.66Al2Se3.53 reveal a Curie Weiss temperature of −216 K, and a spin-freezing transition temperature of 4.5 K, giving a frustration index f = − θ cw/ T f ≈ 48. Ni0.61Al2Se3.55 possesses an effective moment of 2.38 µ B, a Curie–Weiss temperature of −62 K with no sign of spin-freezing transition down to 2 K. The AC susceptibility data of Co0.66Al2Se3.53 suggest a spin glass-like transition, but no intersite mixing between Co2+ and Al3+ was observed from the X-ray photoelectron spectroscopy measurements. [ABSTRACT FROM AUTHOR]

Recently, stripe antiferromagnetic spin fluctuations have been observed in SrCo2As2, which are similar to those found in AFe2As2 superconductors. It is interesting to tune the magnetic properties of this compound to induce superconductivity by chemical doping or applied pressure. Here we present careful chemical doping studies on SrCo2As2 by doping the element La on the Sr sites. We found that a dramatic alteration of the magnetic behavior (from paramagnetism to ferromagnetism) was induced by the incorporation of traces of La (2.5%). The results show that ferromagnetic order is preferred over A-type AFM or stripe-type AFM order when SrCo2As2 is electron-doped. On this basis, in order to regulate its magnetic ground state with the aim of inducing superconductivity, hole-doping may be superior to electron-doping. Furthermore, an unusual magnetic phase diagram between SrCo2As2 and LaCo2As2 is also presented in this work. [ABSTRACT FROM AUTHOR]