Development of Ambient Nanogibbsite Synthesis and Incorporation of the Method To Embed Ultrafine Nano-Al(OH)₃ into Channels and Partial Alumination of MCM-41

An ultrafine aluminum hydroxide nanoparticle suspension was prepared via the controlled titration of [Al­(H₂O)₆]³⁺ with l-arginine to pH 4.6. The prepared material, predominantly 10–30 nm in diameter, was purified by GPC and subsequently identified as the gibbsite (or hydrargillite) polymorph via FTIR, powder XRD, and elemental analysis. The material’s chemical environment and morphology were probed using ²⁷Al/¹H NMR, FTIR, ICP-OES, TEM-EDS, XPS, XRD, and N₂ adsorption experiments. Furthermore, by incorporating the newly developed synthetic route, Al­(OH)₃ was partially loaded inside the mesopores (2.7 nm) of MCM-41. EDS and NMR analysis indicated that both tetrahedral and octahedral Al (O_h/T_d = 1.4) are incorporated at 11% w/w total Al and that the Si/Al ratio is 2.9, indicating that part of the Al is embedded in the Si framework. In addition, differences in elemental composition between surface XPS and bulk EDS analysis provided insight into the distribution of Al within the material. A higher Si/Al ratio was observed on the external surface (3.6) of MCM-41 compared to that of the internal (2.9) cavities. Estimated O/Al ratios suggest predominantly Al­(O)₃ and Al­(O)₄ motifs present near the core and external surface, respectively. This novel methodology produces Al-MCM-41 with relatively high Al content while preserving the ordered SiO₂ framework and can be used in lateral applications where incorporating hydrated or anhydrous Al₂O₃ is desired

Concentration series for four <i>Gingko biloba</i> secondary metabolites.

<p>Concentration series for four <i>Gingko biloba</i> secondary metabolites.</p

Repellent rate of medicament with <i>Gingko biloba</i> secondary metabolites to <i>Hyphantria cunea</i> larvae.

<p>EGB: extract of ginkgo biloba; GF: gingko flavonoids; GL: ginkgolide; BB: bilobalide; CG: control group.</p

Classification of tree health based on the extent of pest feeding and the degree of damage to Ginkgo biloba.

<p>Classification of tree health based on the extent of pest feeding and the degree of damage to Ginkgo biloba.</p

Antifeedant rate of leaf discs soaked by treated with <i>Gingko biloba</i> secondary materials.

<p>EGB: extract of ginkgo biloba; GF: gingko flavonoids; GL: ginkgolide; BB: bilobalide.</p

Instars of <i>Hyphantria cunea</i> larvae infesting branches treated with <i>Ginkgo biloba</i> secondary metabolites.

<p>Instars of <i>Hyphantria cunea</i> larvae infesting branches treated with <i>Ginkgo biloba</i> secondary metabolites.</p

Analysis of artificial diet choice by <i>Hyphantria cunea</i> larvae using diets containing different types of <i>Gingko biloba</i> secondary materials.

<p>A: 4% extract of ginkgo biloba; B: 8% extract of ginkgo biloba; C: 16% extract of ginkgo biloba; D: 2% gingko flavonoids; E: 0.4% ginkgolide; F: 0.2% bilobalide.</p

Analysis of the enzyme activities of four detoxifying enzymes of <i>Hyphantria cunea</i> larvae fed artificial diets with <i>Gingko biloba</i> secondary metabolites.

<p>(A)The enzymatic activity of GSTs were measured in different feeding time. (B)The enzymatic activity of GSTs were measured in different larvae instar. (C)The enzymatic activity of CarE were measured in different feeding time. (D)The enzymatic activity of CarE were measured in different larvae instar. (E)The enzymatic activity of AChE were measured in different feeding time. (F)The enzymatic activity of AChE were measured in different larvae instar. (G)The enzymatic activity of MFO were measured in different feeding time. (H)The enzymatic activity of MFO were measured in different larvae instar. EGB: extract of ginkgo biloba; GF: gingko flavonoids; GL: ginkgolide; BB: bilobalide; CG: contral group. Different letters above bars indicate significant differences (P<0.05).</p

A Water-Soluble Cationic Zinc Lysine Precursor for Coating ZnO on Biomaterial Surfaces

A novel water-soluble cationic zinc lysine coordination compound, [Zn­[(C₆H₁₄N₂O₂)]₂Cl]­Cl·2H₂O (<b>1</b>), has been designed and synthesized and its crystal structure determined. The aqueous solution of this coordination compound is not only transparent and stable at room temperature but it is also nearly neutral (pH ∼ 7). It is worth noting that zinc oxide (ZnO) forms in situ upon dilution of a solution of the compound. The bioactivity of ZnO has been confirmed using an Alarma Blue assay. These unique properties allow the coordination compound to gently grow ZnO coating with excellent antibacterial benefits onto biomaterial surfaces in a facile and safe manner

Solid-State ²⁷Al NMR Spectroscopy of the γ‑Al₁₃ Keggin Containing Al Coordinated by a Terminal Hydroxyl Ligand

We report solid-state ²⁷Al NMR spectroscopic results for the sulfate salt of the γ-Al₁₃ Keggin cluster, γ-[AlO₄Al₁₂(OH)₂₅(OH₂)₁₁]­[SO₄]₃·[H₂O]₁₄, that provide a spectroscopic signature for partial hydrolysis of this Keggin-type cluster. In ²⁷Al multiple-quantum magic-angle spinning NMR spectra, all 13 Al positions of the cluster are at least partially resolved and assigned with the aid of density functional theory (DFT) calculations of the ²⁷Al electric field gradients. The isotropic chemical shift of the single tetrahedral site, 75.7 ppm, is nearly identical to that reported for solutions from which the cluster crystallizes. Reflecting broadly similar coordination environments, the octahedral Al show mostly small variations in isotropic chemical shift (+7 to +11 ppm) and quadrupolar coupling constant (<i>C</i>_Q; 6–7.5 MHz), except for one resonance that exhibits a much smaller <i>C</i>_Q and another site with a larger value. DFT calculations show that deprotonation of a terminal water ligand, to form an η-OH group, causes a large reduction in the ²⁷Al <i>C</i>_Q, allowing assignment of a distinct, narrow peak for octahedral Al to this hydroxyl-terminated site. This result suggests a relationship between octahedral ²⁷Al NMR line width and hydrolysis for solids prepared from Keggin-type clusters