A critical factor for electronics based on inorganic layered crystals stems from the electrical contact mode between the semiconducting crystals and the metal counterparts in the electric circuit. Here, a materials tailoring strategy via nanocomposite decoration is carried out to reach metallic contact between MoS matrix and transition metal nanoparticles. Nickel nanoparticles (NiNPs) are successfully joined to the sides of a layered MoS crystal through gold nanobuffers, forming semiconducting and magnetic NiNPs@MoS complexes. The intrinsic semiconducting property of MoS remains unchanged, and it can be lowered to only few layers. Chemical bonding of the Ni to the MoS host is verified by synchrotron radiation based photoemission electron microscopy, and further proved by first-principles calculations. Following the system's band alignment, new electron migration channels between metal and the semiconducting side contribute to the metallic contact mechanism, while semiconductor-metal heterojunctions enhance the photocatalytic ability.

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Direct sunlight-induced water splitting for photocatalytic hydrogen evolution is the dream for an ultimate clean energy source.

Somatostatin (SST) and its receptors (SSTR1-5) appear to be important in central regulation of many metabolic systems that affect growth, adiposity and nutrient absorption. In this study, we investigated polymorphisms within the caprine SST and SSTR1 genes and determined their relationship with growth traits. As there were no sequence information of the caprine SST and SSTR1 genes, we explored their DNA sequence and genomic organizations. The caprine SST gene is organized in two exons and is transcribed into an mRNA containing 351 bp of sequence coding for a protein of 116 amino acids. Its protein sequences showed substantial similarity (97-99%) to its respective orthologs from cattle, human and mouse. We also cloned and sequenced a 1.2 kb DNA fragment which contained the major part of the coding region and 3' UTR of the caprine SSTR1 gene. We then detected the polymorphisms in these determined sequences by PCR-SSCP and DNA sequencing methods in 459 goats from four breeds. Four SNPs (GU014693:g.647T>C, GU014693:g.844A>C, GU014693:g.970T>C, GU014693:g.1039T>A), segregating as two haplotypes (T-A-T-T and C-C-C-A), were identified in intron 1 of the caprine SST gene and showed the associations to body length and body height (P < 0.05). Two SNPs (GU014695:g.801 C>T, GU014695:g.948 C>T) were identified in the caprine SSTR1 gene. Significant associations between the three genotypes of GU014695:801 C>T and body length, body height, and chest circumference was observed (P < 0.05). These results suggest that the caprine SST and SSTR1 genes are strong candidate genes that influence growth traits in goat.

Pioneering explorations of the two-dimensional (2D) inorganic layered crystals (ILCs) in electronics have boosted low-dimensional materials research beyond the prototypical but semi-metallic graphene. Thanks to species variety and compositional richness, ILCs are further activated as hosting matrices to reach intrinsic magnetism due to their semiconductive natures. Herein, we briefly review the latest progresses of manipulation strategies that introduce magnetism into the nonmagnetic 2D and quasi-2D ILCs from the first-principles computational perspectives. The matrices are concerned within naturally occurring species such as MoS 2 , MoSe 2 , WS 2 , BN, and synthetic monolayers such as ZnO and g-C 2 N. Greater attention is spent on nondestructive routes through magnetic dopant adsorption; defect engineering; and a combination of doping-absorbing methods. Along with structural stability and electric uniqueness from hosts, tailored magnetic properties are successfully introduced to low-dimensional ILCs. Different from the three-dimensional (3D) bulk or zero-dimensional (0D) cluster cases, origins of magnetism in the 2D space move past most conventional physical models. Besides magnetic interactions, geometric symmetry contributes a non-negligible impact on the magnetic properties of ILCs, and surprisingly leads to broken symmetry for magnetism. At the end of the review, we also propose possible combination routes to create 2D ILC magnetic semiconductors, tentative theoretical models based on topology for mechanical interpretations, and next-step first-principles research within the domain.

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In this work, we present laser coloration on 304 stainless steel using nanosecond laser. Surface modifications are tuned by adjusting laser parameters of scanning speed, repetition rate, and pulse width. A comprehensive study of the physical mechanism leading to the appearance is presented. Microscopic patterns are measured and employed as input to simulate light-matter interferences, while chemical states and crystal structures of composites to figure out intrinsic colors. Quantitative analysis clarifies the final colors and RGB values are the combinations of structural colors and intrinsic colors from the oxidized pigments, with the latter dominating. Therefore, the engineering and scientific insights of nanosecond laser coloration highlight large-scale utilization of the present route for colorful and resistant steels.

As an improvement over organic or inorganic layered crystals, the synthetic monolayer ZnO(M) inherits semiconductivity and hostability from its bulk, yet it acts as a promising host for dilute magnetic semiconductors. Here, we report the electronic and magnetic properties of ZnO(M) doped with one 3d transition metal ion and simultaneously adsorbed with another 3d transition metal ion. Two sequences are studied, one where the dopant is fixed to Mn and the adsorbate is varied from Sc to Zn and another where the dopant and adsorbate are reversed. First-principles results show that the stable adsorbed−doped systems possess a lower bandgap energy than that of the host. System magnetic moments can be tuned to |5 – x |μ B , where x refers to the magnetic moment of the individual 3d atom. An interplay between superexchange and direct exchange yields a ferromagnetic system dually adsorbed−doped with Mn. In addition to a novel material design route, the magnetic interaction mechanism is found beyond two dimensions, having been identified for its three-dimensional bulk and zero-dimensional cluster counterparts.