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Mutual dependence and shared geographic distributions of ectomycorrhizal fungi and their hosts suggest that comigration has had an influential role in the evolution of the ectomycorrhizal symbiosis. To test the hypothesis of comigration of ectomycorrhizal symbionts we conducted a phylogeographic analysis of host specific ectomycorrhizal fungi in genus Rhizopogon sampled throughout the natural range of their Pseudotsuga (Douglas fir) hosts. Low coverage genome assemblies were sequenced for all Rhizopogon species-level clades and a novel data mining method, genome-scale sequence typing, was developed to produce a genome-scale phylogenetic dataset. Phylogenetic and phylogeographic analyses support a single evolutionary origin of the Rhizopogon-Pseudotsuga ectomycorrhizal symbiosis in coastal western North America with a single migration into Asia and two independent migrations east into the North American Intermountain West. Our results suggest that the Rhizopogon-Pseudotsuga ectomycorrhizal symbiosis predates species radiation in Pseudotsuga and that these genera have undergone processes of comigration and codiversification. • The Rhizopogon-Pseudotsuga ectomycorrhizal symbiosis evolved once in Rhizopogon. • Genome-scale sequence typing mines phylogenetic data from unannotated genomes. • We support the hypothesis of comigration between ectomycorrhizal symbionts. • The Rhizopogon - Pseudotsuga symbiosis first occurred in western North America. • There was a single migration of the Rhizopogon-Pseudotsuga symbiosis into Asia. [ABSTRACT FROM AUTHOR]

Abstract Mechanically-strong sodium alginate/clay aerogel were fabricated by addition of p-toluenesulfonic acid using a freeze-drying method. The adjusting of pH from 8 (the control) to 6, on the one hand lead to the crosslinking of alginate, on the other hand thickened the clay sol. The compressive modulus of A5C5 aerogel significantly increased from 6.0 ± 0.4 MPa (pH = 8) to 17 ± 3 MPa (pH = 6). The morphological structure characterization showed that the microstructure of aerogels changed from layered to network with decreasing pH value, with cell size ranging from 4 to 8 μm. The rheological behavior showed that the addition of p-toluenesulfonic acid would significantly improve the viscosity of the precursors at low frequency. The combustion tests indicated that all the alginate/clay aerogels possess excellent flame retardancy. The addition of p-toluenesulfonic acid further slightly increased the thermal stability and fire safety of the material. This facile preparation procedure of strengthened polymer/clay aerogel via adjusting pH is promising and can be spread. [ABSTRACT FROM AUTHOR]

To obtain a substitute for petroleum-based polyols and simultaneously solve the flammability problem of polyisocyanurate (PIR) foams, a novel phosphorus-containing soy-based polyol (PCSO) was firstly synthesized. Then, PCSO was used to fabricate biomass flame-retardant PIR foam (P-PIR) by fully replacing petroleum-based polyol. The morphology, compressive strength, thermal conductivity, thermal stability, flammability, and flame-retardant mechanism were studied for the developed PIR. The incorporation of PCSO results in a slight decrease in the compressive strength and an increase in the flame retardancy of PIR foam. To further improve the flame retardancy, a commercial phosphorus-containing polyol (BY30) and an expandable graphite (EG) were added in the P-PIR system. The test results show that the decompositon of PIR was hindered after 330 °C and the char residue was significantly improved. In addtion, the limiting oxygen index of PIR was significantly increased to 35%, and the peak of heat release rate and total heat release were dramatically decreased by 65% and 87%, respectively. A synergistic flame-retardant effect was achieved by combining the gas phase action of PCSO and BY30 with the condensed phase action of EG. [ABSTRACT FROM AUTHOR]

Abstract: Molecular dynamics simulations were carried out to investigate the adsorption mechanisms of tripeptide Arg-Gly-Asp (RGD) on the nanotopography and perfect rutile TiO2 (110) surfaces in aqueous solution. It is shown that the amino groups (NH2 and ) and carboxyl group (COO−) of RGD are the main groups bonding to hydrophilic TiO2 surface by electrostatic and van der Waals interactions. It is also demonstrated that RGD adsorbs much more rapidly and stably on the nanotopography surface than the perfect surface. On the hydrophilic TiO2 surface, the water molecules occupy the adsorption sites to form hydration layers, which have a significant influence on RGD adsorption. On the perfect surface, since the fivefold titanium atom is surrounded by surface bridging oxygen atoms above it and has a water molecule bonding to it, the amino group NH2 is the adsorption group. However, because the pit surface exposes more adsorption sites and has higher surface energy, RGD can adsorb rapidly on the surfaces by amino groups NH2 and , and the carboxyl group COO− may edge out the adsorbed water molecules and bond to the surface titanium atom. Moreover, the surface with higher surface energy has more adsorption energy of RGD. [Copyright &y& Elsevier]

Highlights • Self-cross-linked aerogel based on pectin and melamine-formaldehyde resin was fabricated. • MF-pectin aerogels have significantly increased compressive moduli. • MF-pectin aerogels possess excellent water resistance and low flammability. Abstract Self-cross-linked aerogel based on pectin and melamine-formaldehyde resin (MF) was fabricated via freeze-drying method using water as solvent, where pectin is structural material meanwhile acting as acid to catalyse the cross-linking of MF. The cross-linking reaction easily occurs without additional additives, which can be significantly accelerated at elevated temperatures, with a critical value of about 55 °C. The obtained aerogel shows network microstructures as observed with SEM. With increasing pectin content, the aerogel shows significantly increased compressive modulus. The compressive modulus of M10Pe5 arrives 23.2 MPa, the specific modulus of which arrives 188 MPa cm3/g, while pure MF aerogel are too fragile to keep intact after freeze-dried. The resulting aerogel has good thermal stability, excellent water resistance (can be second dried with limited strength loss) and low flammability. This partially bio-based novel aerogel with impressive properties is promising in many applications. [ABSTRACT FROM AUTHOR]

Biomass aerogels possessing both resilience and flame retardance exhibit great potential as alternatives to fossil-based thermal insulators. Nevertheless, the functional applications of elastic biomass aerogels are impeded by their poor resilience persistence, especially at low temperatures. Herein, a synergetic strategy was proposed for designing biomass aerogels with exceptional elasticity across a broad temperature range (from 150 °C to −78 °C), by strategically manipulating their microstructure and implementing a chemically cross-linked network. The resultant aerogels suffered from slight plastic deformation of only 6.1 % even after 1000 loading-unloading cycles at a strain of 60 %, manifesting super-elastic performance. Additionally, the structure and resilience of aerogel can be well maintained even under frigid temperatures (−78 °C). Because firmly cross-linked networks and loosely packed microstructures with elongated cell walls were constructed to minimize plastic deformation and bending stress, thereby suppressing structural destruction. Furthermore, the resulting biomass aerogel exhibited a remarkable combination of advantageous properties including lightweight, flame retardance (limiting oxygen index of 29 %), thermal insulation (32.8 mW m−1 K−1) and infrared stealth. This research offers new insights into the design of elastic biomass aerogels with exceptional overall performance. By strategically manipulating the microstructure and implementing a chemically cross-linked network, a biomass aerogel was fabricated with flame retardance, thermal insulation, and exceptional elasticity across a wide temperature range. [Display omitted] • Bomass aerogel was prepared with super-elasticity by manipulating microstructure and chemical cross-linked networks. • Cross-linked networks and loose microstructures with elongated walls minimize deformation and bending stress, suppressing destruction. • The resilient performance of aerogels can be maintained from 150 °C to −78 °C. • This aerogel exhibits lightweight, flame retardance, thermal insulation and infrared stealth. [ABSTRACT FROM AUTHOR]

Abstract: An efficient flame retardant polymeric synergist poly[N 4-bis(ethylenediamino)-phenyl phosphonic-N 2, N 6-bis(ethylenediamino)-1,3,5-triazine-N-phenyl phosphonate] (PTPA) was designed and synthesized from cyanuric chloride, ethylenediamine and phenylphosphonic dichloride. It was characterized by Fourier Transform Infrared (FTIR), 1H NMR and 31P NMR, Elemental Analysis (EA) and Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). Combined with ammonium polyphosphate (APP), a new intumescent flame retardant (IFR) was obtained. The flammability behaviors of polypropylene (PP)/IFR system were investigated by limiting oxygen index (LOI), vertical burning test (UL-94) and cone calorimetry. With 25 wt% of IFR (APP:PTPA = 2:1), the PP/IFR system could achieve a LOI value of 34.0% and UL-94 V-0 rating, and the heat release rate (HRR), peak heat release rate (PHRR), total heat release (THR) and smoke production rate (SPR) were considerably reduced, especially HRR and SPR were decreased by 85% and 79%, respectively. The results indicate that there is an excellent synergism between APP and PTPA, which endows PP with both good flame retardancy and good smoke suppression. Furthermore, the thermal degradation mechanism of IFR and the flame-retardant mechanism of PP/IFR system were investigated by thermogravimetric analysis (TGA), FT-IR, TG-FTIR and scanning electron microscope (SEM). The study on the flame-retardant mechanism of IFR indicated that a structure containing –CN was formed due to the reaction between APP and PTPA. [Copyright &y& Elsevier]

Abstract: The formula for surface energy was modified in accordance with the slab model of molecular dynamics (MDs) simulations, and MD simulations were performed to investigate the relaxed structure and surface energy of perfect and pit rutile TiO2(110). Simulation results indicate that the slab with a surface more than four layers away from the fixed layer expresses well the surface characteristics of rutile TiO2 (110) surface; and the surface energy of perfect rutile TiO2 (110) surface converges to Jm−2. The study on perfect and pit slab models proves the effectiveness of the modified formula for surface energy. Moreover, the surface energy of pit surface is higher than that of perfect surface and exhibits an upper-concave parabolic increase and a step-like increase with increasing the number of units deleted along [001] and [110], respectively. Therefore, in order to obtain a higher surface energy, the direction along which atoms are cut out should be chosen in accordance with the pit sizes: [] direction for a small pit size and [001] direction for a big pit size; or alternatively the odd units of atoms along [110] direction are removed. [Copyright &y& Elsevier]

Graphical abstract Waste coffee grounds were catalytically carbonized into functional carbon materials and used as high-efficient adsorbent for organic dyes. Highlights • Biowaste coffee grounds were converted into functional carbon materials. • The carbon yield was as high as 47.6 wt% via direct catalysis by 20 wt% FeCl 3. • The synthesized carbon achieved high surface area and mesoporous structure. • The functional carbon was effective for the removal of different dyes. • The obtained carbon can be magnetically separated and reused multiple times. Abstract Functional carbon materials have been fabricated through simple and effective catalytic carbonization with waste coffee grounds (CGs) as carbon precursor and FeCl 3 as catalyst. The effect of FeCl 3 loading and carbonization temperature on carbon yield was investigated. The morphology and structure of as-synthesized carbons was characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and nitrogen isothermal adsorption/desorption measurement, respectively. Furthermore, the carbon materials showed high efficiency for the removal of methylene blue (MB, 653.6 mg g−1), methyl orange (MO, 465.8 mg g−1) and rhodamine B (RB, 366.1 mg g−1). More importantly, the carbon was magnetic, so it can be easily separated by a magnet and reused multiple times. This work not only exploited a low–cost and large-scale preparation method to synthesize functional carbon materials from bioresources, but also provided an eco-friendly and effective adsorbent in water purification applications. [ABSTRACT FROM AUTHOR]

Inspired by the semi-quantum protocols, this paper defines the lightweight quantum security protocols, in which lightweight participants can only perform at most two out of four very lightweight quantum operations. Subsequently, this study proposes a Lightweight Mediated Quantum Key Distribution (LMQKD) protocol as an example to show the feasibility and advantage of the lightweight quantum protocol. In the proposed protocol, a dishonest third party (TP) with complete quantum capabilities helps two lightweight quantum users establish a secure key. The lightweight quantum users are allowed to perform only: (1) unitary operations and (2) reflecting qubits without disturbance. The proposed protocol has been showed to be robust under the collective attack. [ABSTRACT FROM AUTHOR]

Flavin-containing monooxygenase 3 (FMO3) plays a critical role in catalyzing the conversion of trimethylamine (TMA) to trimethylamine- N -oxide (TMAO) in vivo . Despite the well-documented association between FMO3 mutations and a ‘fishy’ off-flavor eggs in chicken and quail, little information is available regarding the molecular characteristic of goose ( Anser cygnoides ) FMO3 and its relationship with the yolk TMA content. To fill these gaps, we cloned the full-length cDNA sequence of goose FMO3 , which comprised 1851 bp encoding 531 amino acids. FMO3 mRNA was dramatically expressed in liver than in other tissues in the geese. Eight single nucleotide polymorphisms (SNPs) were detected in the entire coding region. The CC genotype at the T669C site, GG at the A723G site, and AA at the G734A site of FMO3 were highly significantly associated with elevated TMA content in goose egg yolk ( P < 0.001). Carriers of the A allele of G734A or C allele of T885C had yolk TMA content that had a high probability of being elevated after feeding with additional choline chloride ( P = 0.0429, OR = 4.1300, 95%CI = 1.0390–16.4270, and P = 0.0251, OR = 4.6060, 95%CI = 1.1620–18.2620, respectively). This work lays a foundation for studying the function of FMO3 and yolk TMA content in goose. However, studies using larger sample sizes and more goose breeds are required to determine whether the fishy off-flavor trait exists in goose. [ABSTRACT FROM AUTHOR]

The intumescence, compactness, and strength of char are the key points to the intumescent flame retardant system. However, the char residues of flame retardant polymers rarely exhibit all three characteristics, especially strength. Herein, a novel Cu2+-doped intumescent flame retardant (Cu–CHP) was prepared without producing any waste. When Cu–CHP was exposed at a high temperature (∼1400 °C), it can rapidly expand and carbonize to form dense char. Surprisingly, the intumescent char residue of Cu–CHP can hold up more than 2000 times its own weight. Benefitting from the excellent intumescent charring capacity of Cu–CHP, the resultant EP/Cu–CHP 18% composite can withstand around 600 s penetrating of butane flame (∼1400 °C) because of strong dense char protection, and only 0.9 wt% Cu2+ content resulted in the limiting oxygen index (LOI) of EP/Cu–CHP 18% increases to 31% and the vertical burning (UL-94) reaches V-0 rating. Additionally, its peak heat release rate, total smoke production, and fire growth rate are significantly reduced by 70%, 53%, and 75%, respectively, compared with neat epoxy resin. Especially, the smoke density of EP/Cu–CHP 18% was dramatically dropped by more than 68%. Because a Cu2+-doped intumescent, compact, and strong char residue was produced during burning. This work provides a new strategy to impart excellent flame retardancy and smoke suppression to highly flammable polymers by building metal-doped strong intumescent char residues. [Display omitted] • Cu2+-doped flame retardant was prepared without producing any wastes. • Cu2+-doped intumescent, compact, and strong char residue was produced. • Excellent flame retardancy and smoke suppression were imparted to epoxy resin. • The intumescent flame retardant mechanism was proposed. [ABSTRACT FROM AUTHOR]

Abstract: Ammonium polyphosphate (form I APP) was modified via ion exchange reaction with ethylenediamine, and the resulting modified ammonium polyphosphate (MAPP) was used alone to prepare intumescent flame-retardant (IFR) polypropylene (PP) via melt blending. The flame retardancy of PP containing MAPP was investigated by limiting oxygen index (LOI), vertical burning test (UL-94) and cone calorimeter (CC). The LOI value of PP containing 40 wt% of MAPP reached 32.5%, which increased by 56.9% compared with that of PP with the same content of APP, and the UL-94 rating was V-0 in the case of specimen thickness of 1.6 mm, while the latter had no rating. CC test results showed that the heat release rate (HRR), the mass loss rate (MLR) and the smoke production rate (SPR）of PP/MAPP system decreased significantly compared with neat PP and PP/APP systems. Especially the fire growth rate (FGR) and SPR peak of PP containing 35 wt% MAPP decreased by 89.1% and 63.2% respectively compared with those of PP containing 35 wt% APP. These results demonstrated that only by incorporating the MAPP without additional charring agents, could PP be successfully flame retarded. Fourier transform infrared spectroscopy (FTIR) etc. were used to investigate the flame retardant mechanism of MAPP, and it was found that both the generation of carbon–carbon double bonds after the scission of C–N bonds and the residue consisting of some stable structures such as P–N–C and C–N etc. caused the charring ability to increase dramatically, which must be the principal reason for the much better flame retardancy of PP/MAPP system without any additional charring agent compared with APP. [Copyright &y& Elsevier]

The aggregation and plasticizing of most 9,10-dihydro-9-oxa-10-phosphaphenanthrene −10-oxide (DOPO) derived additives often result in deteriorating the glass transition temperature and mechanical properties of epoxy resins (EP). To address this issue, an imide-DOPO derivative (BMP) with bulky aromatic structure was successfully synthesized. Benefitting from the space hindering and intermolecular interaction (π-π stacking) of BMP, it does not lead to the loss of glass transition temperature, and only a minor damage of tensile and impact strengths is caused. Additionally, with only 0.78 wt% loading of phosphorus (10 wt% BMP), the EP/BMP 10% achieves UL-94 V-0 and high LOI value of 35%. Simultaneously, both the heat release rate and total smoke production are markedly reduced. More excitingly, BMP exhibits aggregation-induced emission enhancement of fluorescence in the N, N -dimethylformamide/water mixed solution as well as epoxy resin. This work provides a new insight in simultaneously imparting flame retardancy and fluorescence to epoxy resins without losing glass transition temperature. [Display omitted] • Imide-DOPO derivative exhibits aggregation-induced emission enhancement. • Imide-DOPO derivative endows epoxy resin with excellent flame retardancy. • No loss of T g while the improvement of flame retardancy. • Fluorescence is imparted to the flame retardant epoxy resin. [ABSTRACT FROM AUTHOR]

Aerogel composites based on melamine-formaldehyde (MF) and alginate (A) was fabricated with ice-templated method. The preparation process involves two cross-linking processes, in aerogel precursor at room temperature and in dried aerogel at 80 °C (100% humidity), respectively. Cross-linking was demonstrated to be very efficient for improving the mechanical property and water resistance of MF-A aerogels. The obtained aerogels have compressive moduli ranging from 1.2 MPa to 24.1 MPa. All the cross-linked aerogels display good dimensional stability when soaked in water. The morphological study of MF-A aerogels show a layered or network microstructure, with a homogeneous distribution of MF spheres. Due to low density and porous structure, MF-A aerogels have low thermal conductivity from 0.035 to 0.047 W/m K. MF-A aerogels have good thermal stability and extremely low flammability, with LOI value up to 41%. This novel aerogel from partially bio-based raw material would have promising application prospects. Image 10735 • Fully organic aerogel based on melamine-formaldehyde and alginate was fabricated. • The resulting flame retardant aerogels possess low thermal conductivity. • The obtained aerogels are insoluble in water even fabricated from water solution. [ABSTRACT FROM AUTHOR]

To explore the synergism and mechnism of diverse forms of copper-decorated graphene on improving the fireproof efficiency of ammonium polyphosphate (APP) based polyamide-cured epoxy resin (EP), Cu(0) and Cu(II) decorated graphene hybrids (Cu2+-GO, Cu-rGO and CuO-GNS) were prepared through facile methods and used as synergists in EP/APP system. Cu2+-GO exhibits better synergistic effect with APP than Cu-rGO and CuO-GNS on reducing heat release of EP. Because Cu2+ is easier than Cu and CuO to go through various oxidation states and intermediates, which catalyze EP/APP system rapid formation of protective char layer containing crosslinked junctions of P (V) organic phosphates and Cu (II) salts. CuO-GNS exhibits better smoke suppression and harmful gases reduction in EP/APP matrix, such as aliphatic hydrocarbons, aromatic compounds and CO, due to its better conversion of CO to CO 2 through a redox cycle. This work provides a promising strategy for preparation of EP with excellent flame retardancy and smoke suppression at low addition. Image 1 • Cu2+-GO, Cu-rGO, CuO-rGO were successfully prepared • Cu2+-GO exhibits better synergistic effect on enhancing flame retardancy • CuO-rGO exhibits better synergistic effect on smoke and toxic gases reduction • Cu2+-GO and CuO-rGO are better than Cu-rGO on fixing carbon • Junction of crosslinking chars consist of P(V) organic phosphates and Cu(II) salts [ABSTRACT FROM AUTHOR]