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Objectives: Calcifying nanoparticles (CNPs), referred to as nanobacteria (NB), are recognized to be associated with ectopic calcification. This study aims to isolate and culture CNPs from the dental plaque of patients with periodontal disease and investigate their possible role in unravelling the aetiology of periodontal disease., Material and Methods: Supragingival and subgingival plaques were sampled from 30 periodontitis patients for CNPs isolation and culture. Alkaline phosphatase (ALP) content changes were tracked over time. Positive samples underwent thorough morphological identification via hematoxylin and eosin (HE) staining, Alizarin red S (ARS), and transmission electron microscopy (TEM). The chemical composition of CNPs analysis involved calcium (Ca) and phosphorus (P) content determination, Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD)., Results: The subgingival plaque dental group exhibited a higher CNPs isolation rate at 36.67% (11/30) compared to the supragingival dental plaque group at 66.67% (20/30). ALP activity varied among the positive, negative and control groups. Morphological observation characterized the CNPs as round, oval, and ellipsoid particles with Ca deposits. Chemical analysis revealed the Ca/P ratio was 0.6753. Hydroxyl, methyl, carbonate, phosphate, hydrogen phosphate, and dihydrogen phosphate were detected by FTIR; the main chemical components detected by XRD were hydroxyapatite and tricalcium phosphate., Conclusion: CNPs were found in periodontitis-related dental plaque and exhibited the potential to develop calcified structures resembling dental calculus. However, the potential involvement of ALP in CNPs formation requires deeper exploration, as does the precise nature of its role and the interrelation with periodontitis demand a further comprehensive investigation., (© 2024 The Authors. Clinical and Experimental Dental Research published by John Wiley & Sons Ltd.)

1,3,5-Triazine derivatives have a wide range of biological and pharmaceutical activities. According to the extensive application of this compounds, 3-(4-chloro-6-(4-morpholinophenyl)amino)-1,3,5-triazin-2-yl)amino)-N-methylthiophene-2-formamide was synthesized and characterized by 1H-NMR, 13C-NMR, HRMS, FT-IR, and single crystal X-ray diffraction. Moreover, density functional theory (DFT) calculations of this compound were carried out at B3LYP/6-311 level. The result indicated that the crystal structure was orthorhombic crystal system. Moreover, the biological activity of this compound was evaluated as novel FAK inhibitor. [ABSTRACT FROM AUTHOR]

Abstract Layered double hydroxides (LDHs), also known as brucite (Mg(OH) 2)-like anionic clay compounds, are very convenient precursors with a unique flexibility of tuning component type and molar ratio toward composite nanomaterials in energy storage, such as lithium-ion batteries (LIBs). Conventional binary LDH precursors are typically converted to active/non-active transition-metal oxide composites as anode nanomaterials for LIBs, but either with the aid of additionally introducing highly conductive carbonaceous matrix, or possessing relatively high-content non-active components that greatly lower the reversible specific capacity. Herein, we demonstrate a rational design of a novel single-source precursor of dodecyl sulfonate-intercalated Co2+Co3+Al3+-layered double hydroxide (Co2+Co3+Al3+-LDH) and its conversion to high-Co 9 S 8 -content composite (Co 9 S 8 /S-doped carbon/Al 2 O 3) as high-efficiency anode nanomaterials for LIBs. In-situ X-ray diffraction (XRD) reveals the controllable topotactic transformation via tuning calcination temperature and time. Electrochemical test shows that the composite electrode delivers a reversible capacity of 970 mA h g−1 after 200 cycles at 100 mA g−1, and in particular, a long-term cycling stability of 780 mA h g−1 after 500 cycles at 1 A g−1, manifesting highly enhanced electrochemical performances compared with the counterpart derived from a conventional binary LDH precursor. Monitoring the discharged/charged states by in-situ XRD and ex-situ Raman spectra provides a direct support to the enhancement. Our results show that the LDH precursor-based approach provides an alternative to prepare diverse transition metal sulfides for energy storage. Graphical abstract Image 1 Highlights • High-Co 9 S 8 -content composite is derived from a novel LDH precursor. • In-situ XRD reveals the topotactic transformation. • Enhanced lithium storage is supported by in-situ XRD and ex-situ Raman results. [ABSTRACT FROM AUTHOR]

Bimetallic sulfide ((Ni0.3Co0.7)9S8) nanoparticles confined by dual-carbon nanostructures are prepared by pyrolyzing a mixture of surfactant-intercalated layered double hydroxide and melamine, and deliver a highly reversible capacity and decent rate capability as anode nanomaterials for lithium- and sodium-ion batteries. [ABSTRACT FROM AUTHOR]

In the present work, a La-doped Mg–Al mixed metal oxide supported copper catalyst (Cu/La–MgAlO) was synthesized through a layered double hydroxide precursor route. The materials were characterized by powder X-ray diffraction, transmission electron microscopy, CO2-temperature programmed desorption, Fourier transform infrared spectra of CO2 absorption, and X-ray photoelectron spectroscopy. The results revealed that the introduction of a trace amount of La could significantly improve the surface basicity of the Cu/La–MgAlO catalyst, especially strong Lewis basicity. Compared with the undoped supported Cu catalyst, Cu/La–MgAlO exhibited much higher activity and selectivity in the liquid-phase transfer dehydrogenation of 1-decanol with a 1-decanal yield up to 89%. The excellent catalytic efficiency was mainly ascribed to the surface cooperation between the Lewis basic sites and the adjacent Cu0/Cu+ species. That is, basic sites, especially strong-strength basic sites, held the key to the abstraction of protons from the hydroxyl group in 1-decanol, while the adjacent Cu0 and Cu+ species were responsible for the hydrogen transfer and the adsorption of styrene in the transfer dehydrogenation and hydrogenation reactions, respectively. This study provides a new method for designing cost-effective supported copper-based catalysts highly efficient for the transfer dehydrogenation of primary aliphatic alcohols by modifying the surface basicity of metal oxide supports. [ABSTRACT FROM AUTHOR]

NaGd(WO4)2:Eu3+ nanotubes have been successfully synthesized by the hydrothermal method using carbon nanotubes (CNTs) as removable templates. X-ray diffraction, thermogravimetric and differential thermal analysis, transmission electron microscopy, and photoluminescence were used to characterize the product. It is demonstrated that CNTs are fully coated with an amorphous NaGd(WO4)2:Eu3+ layer, which is about 7 nm thick and almost continuous and uniform. After the NaGd(WO4)2:Eu3+/CNTs composites have been calcined at 500 or 600 °C, NaGd(WO4)2:Eu3+ nanotubes are obtained by removing the CNTs templates, and the outer diameter of that is about 40 nm. The luminescence properties of the NaGd(WO4)2:Eu3+ nanotubes calcined at various temperatures have been investigated. The results indicate that the products exhibit a characteristic red emission peak of Eu3+ ions at 615 nm. The emission intensity decreases with the increasing of annealing temperature, which is probably because a few residual carbons doped in NaGd(WO4)2:Eu3+ nanotubes and many oxygen vacancies could promote the intensity of red emission of Eu3+. [ABSTRACT FROM PUBLISHER]

Abstract: Hexagonal GdBO3:Eu3+ with different morphologies, such as nanofibres, microspheres, microflowers and novel lotus leaf-like microstructures, have been successfully synthesized by complexing-agent-assisted hydrothermal process for the first time. X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected-area electron diffraction (SAED), energy-dispersive spectra (EDS), and photoluminescence (PL) spectroscopy were employed to characterize the as-obtained products. It was found that the reaction temperature and the pH value have crucial influences on the formation and morphology of the resulting structures and morphologies. The possible formation mechanisms for different structures were put forward. A detailed investigation on the photoluminescence of GdBO3:Eu3+ different samples indicate that the luminescence properties of as-obtained GdBO3:Eu3+ phosphors are strongly dependent on the morphology, size and crystallinity. The microflower structure exhibits the strongest red emission. [Copyright &y& Elsevier]

Abstract: Three-dimensional flowerlike YBO3:Tb3+ phosphors have been successfully prepared by an efficient surfactant-free hydrothermal process directly without further sintering treatment. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDS) spectrometry, selected area electron diffraction (SAED), photoluminescence (PL) spectra were used to characterize the samples. The as-obtained samples present flowerlike agglomerates composed of nanoflakes with thickness of 20nm and high crystallinity in spite of the moderate reaction temperature of 180°C. The reaction mechanism has been considered as a dissolution/precipitation mechanism; the self-assembly evolution process has been proposed on homocentric layer-by-layer growth style. The different luminescent intensity with different molar ratio of Y–Tb [Y:Tb=8:2; 7:3; 6:4; 5:5; 4:6], YBO3:Tb3+ phosphors exhibit different light (white, red, green) under ultraviolet excitation, which might find potential applications in the fields such as light display systems and optoelectronic devices. [Copyright &y& Elsevier]

Abstract: Eu(BO2)3 nanowires with diameters of 10–20nm were fabricated through direct sintering Eu(NO3)3·6H2O and H3BO3 with Ag as catalyst. The result of X-ray diffraction (XRD) indicated that the nanowire was single-crystalline with body-centered monoclinic structure. Based on the fact that Ag nanoparticles attached to the tips and middles of nanowires, a vapor–liquid–solid (VLS) growth mechanism of the Eu(BO2)3 nanowires is proposed. Three well-defined stages have been clearly identified during the process: Ag–Eu–B–O cluster process, crystal nucleation, and axial growth. The photoluminescence characteristics under UV excitation were investigated. The dominated Eu3+ orange–red emission corresponding to the magnetic dipole transition 5D0 → 7F1 is centered at 591nm, indicating that Eu3+ is located at high symmetry crystal field with inversion center. [ABSTRACT FROM AUTHOR]

Abstract: Large-scale GdBO3:Eu3+ nanofibres with uniform diameter were controllably synthesized by a glycine-assisted hydrothermal method at 170°C using Gd(NO3)3, Eu(NO3)3 and Na2B4O7·10H2O as the precursors. X-ray diffraction (XRD) results show that the luminescent nanofibres are pure hexagonal structure and no other impurity phase appeared. Transmission electron microscopy (TEM) studies indicate that GdBO3:Eu3+ has a nanofibre structure. Photoluminescence (PL) spectra results demonstrate that the GdBO3:Eu3+ nanofibres have three strong 5D0 → 7F1 (595nm) and 5D0 → 7F2 (613 and 627nm) transition peaks corresponding to orange-red and red colors, respectively. [ABSTRACT FROM AUTHOR]

Ten undescribed highly oxidized sesquiterpenes and six known sesquiterpenes were isolated from H 2 O-soluble part of the fruits of Illicium lanceolatum A. C. Smith. The structures of undescribed compounds were elucidated by interpretation of spectroscopic data, and the absolute configurations of 2 α -hydroxyneoanisatinic acid, (1 R ,5 R ,6 S ,7 R ,9 R ,10 R)-3,4-dehydro-12-hydroxy-floridanolide, and (1 R ,4 S ,5 R ,6 S ,7 S ,9 S)-1-deoxy-13-hydroxymerrilactone B were determined by the single-crystal X-ray diffraction analysis. Illilanceolatin A was the first example of a seco -prezizaane type sesquiterpene with a hemiacetal moiety located at C-10. 2 α -Hydroxyneoanisatinic acid and anisatinic acid were two naturally occurring undescribed seco -prezizaane type sesquiterpenes with a 5/5/6 tricyclic carbon skeleton. Plausible biosynthetic pathways of the isolated polycyclic and highly oxidized sesquiterpenes derived from the intermediate allo -cedrane were proposed. (1 R ,5 R ,6 S ,7 R ,9 R ,10 R)-3,4-dehydro-12-hydroxy-floridanolide, 1,3-dihydroxyneoanisatin, and 2 α -hydroxyneoanisatin displayed neuroprotective effects with protection rates of 19.9, 22.7 and 24.3% at 10 μ M, respectively. Additionally, the preliminary acute toxicity of anisatinic acid was also evaluated. Ten undescribed highly oxidized sesquiterpenes, along with six known analogues were isolated from the fruits of Illicium lanceolatum. Their neuroprotective, cytotoxic, anti-inflammatory, and antiviral activities were evaluated. Image 1 • Ten undescribed highly oxidized sesquiterpenes were isolated from the fruits of Illicium lanceolatum A. C. Smith. • Illilanceolatin A was the first example of a seco -prezizaane type sesquiterpene with a hemiketal moiety located at C-10. • Plausible biosynthetic pathways of sesquiterpenes derived from the intermediate allo -cedrane were proposed. [ABSTRACT FROM AUTHOR]

Five phenylethyne( p -alkoxyphenyl isocyanide)gold(I) complexes with different alkyl chains (OR) in the para -position of the phenyl isocyanide have been successfully synthesized [where R = CH 3 ( 5a ), C 2 H 5 ( 5b ), C 4 H 9 ( 5c ), C 6 H 13 ( 5d ), and C 10 H 21 ( 5e )] and structurally characterized by 1 H NMR, 13 C NMR, and HRMS. To our surprise, the as-prepared powders of these complexes exhibited different emission colors. The diversity of their mechanochromic luminescence properties has been investigated with photoluminescence spectroscopy, powder X-ray diffraction (XRD) analysis, and single-crystal XRD analysis. The results indicated the presence of weak intermolecular interactions in their crystal structures, and different alkyl chains had obvious impacts on their stacking arrangements and optical behavior. The luminescence quantum yield of 5c was as high as 49.3% in the solid state. Complexes 5a – 5e each showed luminescence quenching after grinding. [ABSTRACT FROM AUTHOR]

A dithieno[3,2- b :2′,3′- d ]pyrrole-based luminogen 1 has been synthesized by appending two twisted triphenylamine units to the rigid conjugated dithieno[3,2- b :2′,3′- d ]pyrrole core. This compound exhibits reversible mechanochromic luminescence in the solid state and near-infrared electrochromic switching behavior in solution. A reversible switching in fluorescence color between yellow-green and green can be observed through mechanical grinding and vapor fuming of solid powdered 1 , which involves an interconversion between a crystalline form and an amorphous phase according to X-ray diffraction analysis. The associated oxidized species of 1 show intense redox-switchable near-infrared absorption and different fluorescence colors in solution in spectroelectrochemical and luminescence measurements. Density functional theory calculations have confirmed that there is considerable electron delocalization between the dithieno[3,2- b :2′,3′- d ]pyrrole linker and two triphenylamine redox-active termini during the oxidation process. [ABSTRACT FROM AUTHOR]

Twonew grayanoids, mollanol A (1) and rhodomollein XXV (2), were isolated from the fruits of Rhododendronmolle. Their structures were elucidated by spectroscopicmethods and X-ray diffraction analyses. Mollanol A (1) possesses a new C-nor-D-homograyanane carbon skeleton, whilerhodomollein XXV (2) is the first example of an 11,16-epoxygrayananeand features a caged oxa-tricyclo[3.3.1.03.7]nonane ringsystem. Plausible biogenetic pathways for 1were proposed.Compound 1exhibited transcriptional activation effectson the xbp1upstream promoter in IEC-6, 293T, andRAW264.7 cells. [ABSTRACT FROM AUTHOR]

Abstract: Self-assembled 3D flower-like NaY(MoO4)2:Eu3+ microarchitectures were successfully synthesized by a glycine-assisted hydrothermal method at 180°C. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM) were employed to characterize the as-obtained products. It was found that morphology modulation could be easily realized by changing the time of hydrothermal reaction system. 3D flower-like NaY(MoO4)2:Eu3+ microarchitectures were formed with 72h reaction time. The formation mechanism for flower-like architecture was proposed on the basis of a series of time-dependent experiments. The NaY(MoO4)2:Eu3+ powders obtained can be effectively excited by 396nm light, and exhibit strong red emission around 615nm, attributed to the Eu3+ 5D0 → 7F2 transition. An investigation on the photoluminescence (PL) properties of NaY(MoO4)2:Eu3+ obtained revealed that the luminescence properties were correlated with the morphology and size. [Copyright &y& Elsevier]

Abstract: Eu(III) titanate nanotubes and nanowires have been successfully synthesized by solvothermal method using carbon nanotubes (CNTs) as removable templates. The products were characterized by X-ray diffraction spectroscopy, transmission electron microscopy, energy-dispersive X-ray spectrometry, thermogravimetric and differential thermal analysis. It is demonstrated that CNTs are fully coated with an amorphous Eu2(TiO3)3 layer, which is about 10nm thick and almost continuous and uniform. After the Eu2(TiO3)3/CNTs composites have been calcined at various temperatures, Eu2(TiO3)3 nanotubes and nanowires are obtained by removing the CNTs templates. The diameter of the Eu2(TiO3)3 nanotubes is 40–60nm, which is consistent with that of CNTs. Both nanotubes and nanowires have a narrow distribution of diameters. The fluorescence properties of the Eu2(TiO3)3 nanotubes and nanowires calcined at various temperatures have been investigated. The results indicate that when the Eu2(TiO3)3/CNTs composites were calcined at 700°C for 5h, the Eu2(TiO3)3 nanotubes obtained can be effectively excited by 395nm light, and exhibit strong red emission around 616nm. It is very interesting to discover that a few residual carbons doped in Eu2(TiO3)3 nanotubes and many oxygen vacancies could promote the intensity of red emission peak of Eu3+ ions. In addition, Eu2(TiO3)3 nanowires calcined at 900°C for 5h also have a strong red emission peak due to many oxygen vacancies and defects formed on the surface of the nanowires and inside them. [Copyright &y& Elsevier]

Abstract: Nanocrystalline zinc ferrite (ZnFe2O4) photocatalysts with different crystallite sizes prepared using the colloid mill and hydrothermal technique are reported. This synthetic approach involves a very rapid mixing of Fe3+ cations with reducing agent and reduction process in a colloid mill reactor, followed by a slow oxidation of iron nuclei and structural transformation in a separate hydrothermal process. Material characterization has been presented by powder X-ray diffraction (XRD), chemical element analysis, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM) and UV–vis diffuse reflectance spectra. The results indicate that ZnFe2O4 nanocrystals with the uniform crystallite sizes have been obtained using in situ forming iron nuclei as the source of Fe. A possible formation mechanism of ZnFe2O4 nanocrystals was proposed. Furthermore, through photocatalytic investigation, these ZnFe2O4 nanocrystals displayed better abilities to photodecompose acid orange II azodye molecule under UV irradiation due to quantum confinement effect and high surface area structure, as compared to bulk ZnFe2O4 sample prepared by the conventional solid-state method. Since as-synthesized ZnFe2O4 nanocrystals have excellent chemical and thermal stabilities and exhibit good photocatalytic activities, it can be expected that they may have potential application in the field of industrial photo-degradation of organic azodye pollutants. [Copyright &y& Elsevier]

Abstract Two series of pure nanosized ZSM-22 zeolites (Z-22 (x D) and Z-22 (x S)) with different SiO 2 /Al 2 O 3 molar ratios are synthesized with 1,6-diaminohexane (DAH) template by the hydrothermal method under dynamic and static crystallization conditions, respectively. The effects of crystallization conditions on the characteristic properties of ZSM-22 zeolites are investigated by XRD, SEM, HR-TEM, N 2 adsorption, 29Si and 27Al MAS NMR, NH 3 -TPD, Py-IR and H 2 chemisorption measurements. The results show that Z-22 (x D) samples reveal smaller crystal size, larger mesoporosity, weaker Brønsted acid strength and lower Brønsted acid density compared with Z-22 (x S) samples. The Pd/Z-22 (x D) and Pd/Z-22 (x S) bifunctional catalysts are prepared by loading 0.5 wt% Pd on the corresponding zeolite samples, respectively, and the catalytic performance over all bifunctional catalysts is tested in the hydroisomerization of n- decane. The catalytic test results indicate that the Pd/Z-22 (x D) catalysts show higher selectivity for both mono-branched and multi-branched iso -decanes than those of Pd/Z-22 (x S) catalysts, because of the smaller crystal size and lower Brønsted acidity. Therefore, the dynamic hydrothermal crystallization is an effective way to synthesize ZSM-22 zeolites with improved catalytic behaviors for the n-alkane hydroisomerization. Graphical abstract Image 1 Highlights • Pure Z-22(x D) samples with improved textural properties are synthesized by dynamic crystallization method. • Z-22(x D) samples reveal smaller crystal size and weaker Brønsted acidity than those of Z-22(xS) samples. • Pd/Z-22(x D) catalysts show higher catalytic behaviors in n -decane hydroisomerization compared with Pd/Z-22(x S) catalysts. • Due to the balance between the mesoporosity and Brønsted acidity, Pd/Z-22(90D) catalyst shows the highest i -decane yield. [ABSTRACT FROM AUTHOR]

A series of leaching experiments were carried out for evaluation of release behavior of Cl in Chinese coal gangue from Yangquan Coal Mine in Shanxi province under different pH conditions (pH = 2.6, 4.2, 6.5, 8.1, respectively) and different leaching durations (up to 105 h). The modes of occurrence of Cl in the coal gangue and its post-leached residues were extracted with sequential chemical extractions; chlorine in solution was determined using IC (ion chromatography); chemical and mineralogical compositions in coal gangue and the post-leached residues were determined by XRD (X-ray diffraction), XRF (X-ray fluorescence spectrum) and FT-IR (Fourier infrared spectrum). The results indicated that kaolinite, quartz, calcite, pyrite and illite were the predominant minerals in coal gangue with a certain amount of organic matter and a little mica. Chlorine in coal gangue occurred in a descending order of significance, as forms of organic matter (P5), Fe-Mn oxides (P4), water-soluble (P1), residue (P6), carbonate (P3), and exchangeable (P2), which accounted for 41.56%, 37.87%, 14.65%, 3.26%, 1.33% and 1.31%, respectively. With the rise of acidity of leaching solution, the reaction rates of most of matrix compositions in coal gangue increased, and more Cl was leached out in a shorter time. Under the condition of pH 2.6, 4.2, 6.5 and 8.1 and leaching duration up to 105 h, the leaching rate of Cl were respectively 57.21% (11.98%, 1.31%, 1.33%, 23.03% and 20.06% for P1, P2, P3, P4 and P5, respectively), 35.97% (8.18%, 1.31%, 0.78%, 14.77% and 10.91% for P1, P2, P3, P4 and P5, respectively), 26.65% (7.52%, 1.31%, 0.42%, 9.87% and 7.53% for P1, P2, P3, P4 and P5, respectively) and 18.98% (5.32%, 0.60%, 1.33%, 7.61% and 5.45% for P1, P2, P3, P4 and P5, respectively). Chlorine in coal gangue may pose an environmental risk with the increase of acidity of environmental aqueous solution. [ABSTRACT FROM AUTHOR]

Abstract: NiFe2O4/NiO nanocomposite thin films have been successfully prepared through a facile route using nickel iron layered double hydroxide (NiFe–LDH) as a single-source precursor. This synthetic approach mainly involves the formation of NiFe–LDH film by casting the slurry of NiFe–LDH precursor on the α-Al2O3 substrate, followed by high-temperature calcination. The composition, microstructure and properties of the films were characterized in detail by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX) and vibrating sample magnetometer (VSM). The results indicate that NiFe2O4/NiO composite film was composed of granules with diameter less than 100nm, and the thickness of the film was in the range 1–2μm. The magnetization of the film can be tuned by alternating the Ni/Fe molar ratio of LDH precursor. In addition, the method developed should be easily extended to fabricate other MFe2O4/MO composite film systems with specific applications just by an appropriate combination of divalent/trivalent composition in the precursor of LDHs. [Copyright &y& Elsevier]