Noble-Metal-Free Iron Phosphide Cocatalyst Loaded Graphitic Carbon Nitride as an Efficient and Robust Photocatalyst for Hydrogen Evolution under Visible Light Irradiation

Photocatalytic hydrogen (H₂) evolution from water is a promising and sustainable approach for solar-to chemical energy conversion. However, the development of an efficient, robust, and low-cost visible-light-driven photocatalyst for H₂ evolution is still one of the great challenges. Graphitic carbon nitride (g-C₃N₄) is an attractive candidate, but the activity of pristine g-C₃N₄ is largely limited. Herein, for the first time, we report the noble-metal-free iron phosphide cocatalyst decorated graphitic carbon nitride (g-C₃N₄/Fe_<i>x</i>P) as a photocatalyst for the highly efficient and stable H₂ evolution from water splitting irradiated by visible light. The peak H₂ evolution rate of g-C₃N₄/Fe_<i>x</i>P is ca. 277 times higher than that of pristine g-C₃N₄ and is almost comparable with the g-C₃N₄ modified by noble metal Pt cocatalyst. Additionally, g-C₃N₄/Fe_<i>x</i>P demonstrates almost negligible photocatalytic degradation capability after five repeated cycles. Based on the detail analyses of photoluminescence and surface photovoltage spectra, we find the presence of Fe_<i>x</i>P cocatalyst significantly accelerates the separation and transfer of photogenerated electrons of g-C₃N₄, hence resulting in the high photocatalytic efficiency of g-C₃N₄/Fe_<i>x</i>P for H₂ production. In addition, the adjacent Fe and P atoms in Fe_<i>x</i>P act as dual proton adsorption sites to synergistically facilitate the fast H₂ generation from water

Additional file 1 of Evaluation of physical fitness and health of young children aged between 3 and 6 based on cluster and factor analyses

Additional file 1

Replacing the 238th aspartic acid with an arginine impaired the oligomerization activity and inflammation-inducing property of pyolysin

<p><i>Trueperella pyogenes</i> (<i>T. pyogenes</i>) is an important opportunistic pathogen. Pyolysin (PLO) importantly contributes to the pathogenicity of <i>T. pyogenes</i>. However, the relationship between the structure and function and the virulence of PLO is not well documented. In the current study, recombinant PLO (rPLO) and three rPLO mutants were prepared. rPLO D238R, a mutant with the 238th aspartic acid replaced with an arginine, showed impairment in oligomerization activity on cholesterol-containing liposome and pore-forming activity on sheep red blood cell membrane. Further study employing the prepared mutants confirmed that the pore-forming activity of PLO is essential for inducing excessive inflammation responses in mice by upregulating the expression levels of IL-1β, TNF-α, and IL-6. By contrast, rPLO P499F, another mutant with impaired cell membrane binding capacity, elicited an inflammation response that was dependent on pathogen-associated molecular pattern (PAMP) activity, given that the mutant significantly upregulated the expression of IL-10 in macrophages and in mice, whereas rPLO did not. Results indicated that domain 1 of the PLO molecule plays an important role in maintaining pore-forming activity. Moreover, the PLO pore-forming activity and not PAMP activity is responsible for the inflammation-inducing effect of PLO. The results of this study provided new information for research field on the structure, function, and virulence of PLO.</p> <p><b>Abbreviations</b>: <i>T. pyogenes: Trueperella pyogenes</i>; PLO: Pyolysin; rPLO: recombinant PLO; PAMP: pathogen-associated molecular pattern; CDCs: cholesterol-dependent cytolysins; PLY: pneumolysin; NLRP3: NLR family pyrin domain containing protein 3; PRRs: pattern recognition receptors; Asp: aspartic acid; TLR4: Toll-like receptor 4; Arg: arginine; Asn: asparagine; IPTG: Isopropyl-β-d-thiogalactoside; PBS: phosphate-buffered saline; sRBCs: sheep red blood cells; TEM: Transmission electron microscopy; RBCM: red blood cell membrane; SDS-PAGE: sodium dodecyl sulfate–polyacrylamide gel electrophoresis; NC membrane: nitrocellulose membrane; SDS-AGE: dodecyl sulfate agarose gel electrophoresis; MDBK cells: Madin–Darby bovine kidney cells; RPMI-1640 medium: Roswell Park Memorial Institute-1640 medium; FBS: fetal bovine serum; BMDMs: bone marrow-derived macrophages; TNF-α: tumor necrosis factor α; IL-1β: interleukin-1β; IFN-γ: interferon-γ; TGF-β: transforming growth factor-β; ELISA: enzyme-linked immunosorbent assay</p

Fabrication of Flexible Thermoplastic Polyurethane/Coal Hydrogasification Semi-coke Composites with Low rGO Content for High-Performance Microwave Absorption

Semi-coke (SC), a residue of coal hydrogasification, is recycled and incorporated into thermoplastic polyurethane (TPU) to create composites for microwave absorption (MA). Herein, we developed porous reduced SC (rSC)–reduced graphene oxide (rGO) hybrids (SGHs) via in situ reduction of a preoxidized SC (oSC) and graphene oxide (GO) mixture. Low-content GO was introduced to considerably improve the dielectric properties of SGHs while decreasing the production cost. Then, a solution blending technique was applied to develop microwave absorbers using TPU as the matrix. The obtained TPU/SGH5 composite with a feed ratio of 5:1 (oSC:GO) showed an optimum reflection loss of −48.81 dB at a thickness of 2.5 mm and an effective absorption bandwidth of 4.30 GHz (7.74–12.04 GHz) in 2–18 GHz. However, the MA property of the obtained composites with the same amount of rSC or rGO alone was not comparable to that of the TPU/SGH5 composite. The inherent magnetism, heteroatoms, and abundance of heterogeneous surfaces of rSC and the considerable dielectric loss of rGO worked together to improve the MA performance of TPU/SGH composites. This study offers an easy and effective technical method for producing high-performance microwave absorbers with a low rGO content, illuminating the path toward achieving sustainable development by converting waste into wealth

Organoboron-Based Photochromic Copolymers for Erasable Writing and Patterning

We report herein the first examples of organoboron-based photochromic polymers. The synthesis of a series of blue fluorescent random copolymers bearing photochromic boron repeating units, poly­[(6-B­(ppy)­Mes₂)­oxyhexyl methacrylate)_<i>m</i>-<i>r</i>-(<i>tert</i>-butyl methacrylate)_<i>n</i>], ppy = 2-phenylpyridyl and Mes = mesityl, via atom transfer free radical polymerization (ATRP) has been accomplished. These new polymers display thermally reversible photochromism, switching color from colorless to deep blue, and fluorescence from bright sky blue to deep blue. By controlling the monomer ratio, the photoisomerization quantum efficiencies of the polymers can be tuned effectively. In addition, the number of boron units in the polymer has been found to have a significant impact on fluorescence quenching efficiency. The new organoboron-based polymers can be used effectively as a switchable/erasable ink on glass or paper substrate or for creating switchable/erasable patterns as neat polymer films

Lanthanide Complexes with Photochromic Organoboron Ligand: Synthesis and Luminescence Study

A novel, photochromic N^C-chelate organoboron functionalized dipicolinic acid (<b>H₂L</b>) has been designed and synthesized. Lanthanide­(III) complexes based on this ligand (<b>L</b>) with the general formula [NBu₄]₃­[LnL₃] (Ln = Eu or Tb) were prepared. The new ligand was found to be effective in both sensitizing and photomodulating the emission of a Eu­(III) ion. The photoisomerization conversion of the boryl chromophore attached to the ligand of the lanthanide complex was determined to be quantitative by NMR analysis of the La­(III) analogue

One-Pot Synthesis of 3‑Hydroxy­quinolin-2(1<i>H</i>)‑ones from <i>N-</i>Phenyl­aceto­acetamide via PhI(OCOCF₃)₂‑Mediated α‑Hydroxylation and H₂SO₄‑Promoted Intramolecular Cyclization

A clean, one-pot synthesis of the biologically important 3-hydroxyquinolin-2­(1<i>H</i>)-one compounds has been realized from the readily available <i>N</i>-phenylacetoacetamide derivatives through a PhI­(OCOCF₃)₂-mediated α-hydroxylation and a H₂SO₄-promoted intramolecular condensation. The hydroxyl group in the generated α-hydroxylated intermediate can be well tolerated in the second H₂SO₄-promoted cyclization step

Phenyliodine Bis(trifluoroacetate)-Mediated Oxidative C–C Bond Formation: Synthesis of 3-Hydroxy-2-oxindoles and Spirooxindoles from Anilides

The reaction of phenyliodine bis(trifluoroacetate) (PIFA) with a series of anilides <b>1</b> (E = CO₂Et) in CF₃CH₂OH was found to give 3-hydroxy-2-oxindole derivatives <b>2</b>, while that with various anilides <b>1</b>′ (E = CON(R⁴)Ar) afforded the <i>C</i>₂-symmetric or unsymmetric spirooxindoles <b>3</b>. These processes feature a metal-free oxidative C(<i>sp</i>²)–C(<i>sp</i>³) bond formation, followed by oxidative hydroxylation or spirocyclization

Phenyliodine Bis(trifluoroacetate)-Mediated Oxidative C–C Bond Formation: Synthesis of 3-Hydroxy-2-oxindoles and Spirooxindoles from Anilides

The reaction of phenyliodine bis(trifluoroacetate) (PIFA) with a series of anilides <b>1</b> (E = CO₂Et) in CF₃CH₂OH was found to give 3-hydroxy-2-oxindole derivatives <b>2</b>, while that with various anilides <b>1</b>′ (E = CON(R⁴)Ar) afforded the <i>C</i>₂-symmetric or unsymmetric spirooxindoles <b>3</b>. These processes feature a metal-free oxidative C(<i>sp</i>²)–C(<i>sp</i>³) bond formation, followed by oxidative hydroxylation or spirocyclization

Abnormal Development of Tapetum and Microspores Induced by Chemical Hybridization Agent SQ-1 in Wheat

<div><p>Chemical hybridization agent (CHA)-induced male sterility is an important tool in crop heterosis. To demonstrate that CHA-SQ-1-induced male sterility is associated with abnormal tapetal and microspore development, the cytology of CHA-SQ-1-treated plant anthers at various developmental stages was studied by light microscopy, scanning and transmission electron microscopy, in situ terminal deoxynucleotidyl transferasemediated dUTP nick end-labelling (TUNEL) assay and DAPI staining. The results indicated that the SQ-1-treated plants underwent premature tapetal programmed cell death (PCD), which was initiated at the early-uninucleate stage of microspore development and continued until the tapetal cells were completely degraded; the process of microspore development was then blocked. Microspores with low-viability (fluorescein diacetate staining) were aborted. The study suggests that premature tapetal PCD is the main cause of pollen abortion. Furthermore, it determines the starting period and a key factor in CHA-SQ-1-induced male sterility at the cell level, and provides cytological evidence to further study the mechanism between PCD and male sterility.</p></div