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The morphological properties and particle size characteristics of micro- and nanofibrillated cellulose (NFC) and lignin-containing NFC (LNFC) produced by a microfluidizer processor were investigated. The effects mechanism of lignin-containing on the adsorption of NFC and the stable properties of organic dyes suspension were also studied. The results showed that the preparation process and final performance of NFC were affected by the key factors including lignin, homogenization pressure, and number of homogenization cycles. The increase in the homogeneity of the fibrillated cellulose was minor for the NFC samples, while LNFC samples showed a larger increase in the homogeneity of the particle size distribution. The influence of lignin was reflected both in improved fibrillation efficiency and in the final organic dye dispersion properties achieved by LNFC addition, primarily observed as deceased particle sizes and fibril dimensions. This study indicated that pollution-free dispersion of organic dyes can be realized through the application of lignin-containing NFC.

Ginkgo shells as by-products from Ginkgo biloba L. industries with a remarkable annual output up to now are not fully analyzed and exploited. For the application of ginkgo shells beyond their current roles, structure and antioxidant activity of milled wood lignins successively extracted from two ginkgo shell species were investigated. Results showed lignin in ginkgo shells is abundant in guaiacyl units with the presence of ferulates and p-coumarates and demonstrates a high yield of vanillin (1.47–1.65 mmol/g-lignin) by nitrobenzene oxidation, much higher than general softwoods and hardwoods (0.6–0.9 mmol/g-lignin), which makes ginkgo shells good feedstocks for the production of food and beverage flavoring agent. By increasing the extent of ball-milling (4–8 h), the polydispersity of lignin molecular weight exhibits negligible change, but condensation and aldol interconversion occur to its Cβ/C5 structure and end-groups, respectively. Lignin in ginkgo shells also features outstanding antioxidant activity with the optimal radical scavenging index of 6.9, much higher than commercial butyl hydroxyanisole (3.85) and butylated hydroxytoluene (0.29), and the phenolic hydroxyl is demonstrated to dominate this contribution by the analysis of statistical product and service solutions. These results reveal lignin in ginkgo shells shows many unique structural and biological properties for materials.

Transient receptor potential ankyrin 1 (TRPA1), the non-selective cation channel, was found that can mediate the generation of multiple sclerosis, while the mechanism is still controversial. Lysophosphatidylcholine (LPC) is a critical trigger of multiple sclerosis which results from the syndrome of neuronal inflammation and demyelination. In this work, we suggested that TRPA1 can mediate the LPC-induced oxidative stress and cytotoxicity in OLN-93 oligodendrocyte. The expression of TRPA1 in OLN-93 was detected by using quantitative real-time PCR (qRT-PCR) and immunofluorescence. The calcium overload induced by LPC via TRPA1 was detected by calcium imaging. The mechanism of LPC-induced mitochondrial reactive oxygen species (mtROS) generation, mitochondria membrane depolarization, nitric oxide (NO) increase, and development of superoxide production via TRPA1 was verified by using confocal imaging. The cell injury elicited by LPC via TRPA1 was confirmed by both CCK-8 and LDH cytotoxicity detection. These results indicate that TRPA1 plays an important role of the LPC-induced oxidative stress and cell damage in OLN-93 oligodendrocyte. Therefore, inhibition of TRPA1 may protect the LPC-induced demyelination.

An oxygen-enhanced organosolv fractionation method to produce lignin from waste biomass was investigated. In this novel biorefinery process, mild conditions, i.e., temperature at 80 to 100 °C and pressure < 0.8 MPa, were employed to alleviate energy input and to retain the original lignin structure as much as possible. The results showed that the lignin yield was increased with increasing process temperature, ethanol concentration, and ratio of liquid to solid. Although little structural changes were observed, the normalized Infrared transmittance results revealed quantitative differences. Moreover, a basic kinetic study was conducted, and the results showed that there existed two stages with fast and slow rates during the delignification processes. Analysis of the fibers’ micro-structure also demonstrated the effectiveness of oxygen-enhanced organosolv fractionation. However, a phenol-based inducer could possibly further improve the efficiency based on the delignification mechanism of reactive oxygen species, which will be studied in future research.

Polyacene(PAS) /carbon and acetylene black(AB)/carbon coated lithium cobalt phosphate composites were synthesized via the solid state reaction method using co-precipitated Co 3 (PO 4 ) 2 ·8H 2 O and Li 3 PO 4 mixture as its precursor. X-ray powder diffraction (XRD) was performed to investigate the structure and phase of all the samples. The transmission electron microscopy (TEM) shows that the double carbon layers coated on the surface of LiCoPO 4 successfully. The LiCoPO 4 /C, LiCoPO 4 /PAS and LiCoPO 4 /AB delivered a capacity of T 120.92, 121.07 and 138.06 mAh × g -1 at 0.1C, respectively. The double carbon coated LiCoPO 4 electrode delivered an initial discharge capacity of 147.12, 143.51 mAh × g -1 after AB/glucose, PAS/glucose coating, which maintained at 59.5% and 61.7% after 15 cycles at the 0.1C rate, respectively. Citiation: Yu, Y., Zhao, H., Chen, Y., Feng, Z.-k., Liu, X., and Yang, H. (2020). Double Carbon Coated LiCoPO4 Nano Composite as High-Performance Cathode for Lithium Ion Batteries. Trends in Renewable Energy, 6, 1-11. DOI: 10.17737/tre.2020.6.1.00108

Lysophosphatidylcholine (LPC) is a major atherogenic lipid that stimulates an increase in mitochondrial reactive oxygen species (mtROS) and the release of cytokines under inflammasome activation. However, the potential receptors of LPC in macrophages are poorly understood. Members of the transient receptor potential (TRP) channel superfamily, which is crucially involved in transducing environmental irritant stimuli into nociceptor activity, are potential receptors of LPC. In this study, we investigated whether LPC can induce the activation of transient receptor potential ankyrin 1 (TRPA1), a member of the TRP superfamily. The functional expression of TRPA1 was first detected by quantitative real-time polymerase chain reaction (qRT-PCR), western blotting and calcium imaging in human acute monocytic leukemia cell line (THP-1)-derived macrophages. The mechanism by which LPC induces the activation of macrophages through TRPA1 was verified by cytoplasmic and mitochondrial calcium imaging, mtROS detection, a JC-1 assay, enzyme-linked immunosorbent assay, the CCK-8 assay and the lactate dehydrogenase (LDH) cytotoxic assay. LPC induced the activation of THP-1-derived macrophages via calcium influx, and this activation was suppressed by potent and selective inhibitors of TRPA1. These results indicated that TRPA1 can mediate mtROS generation, mitochondrial membrane depolarization, the secretion of IL-1β and cytotoxicity through cellular and mitochondrial Ca2+ influx in LPC-treated THP-1-derived macrophages. Therefore, the inhibition of TRPA1 may protect THP-1-derived macrophages against LPC-induced injury.

Many indica-japonica rice hybrids with great yield heterosis have been successfully developed and widely planted in China. However, these inter-subspecies rice hybrids are inferior to japonica rice in eating and cooking quality (ECQ). In this study, the cooked texture and starch properties of six indica-japonica rice hybrids with the similar amylose content (AC) were analyzed to reveal the relationship between these parameters and ECQ. The fine structure of amylopectin was analyzed using fluorophore-assisted carbohydrate electrophoresis (FACE). AC of the six hybrids ranged from 12.06% (YY17) to 14.39% (YY9), and granule size (GS) of starch was a main factor determining the texture of cooked rice. Rice starch containing more B1 chains and fewer A chains in amylopectin had higher gelatinization temperatures. Better eating quality for YY17 relative to other five hybrids was related to its softer and more sticky texture, higher breakdown viscosity, and lower setback viscosity, while inferior cooking quality is attributed to higher gelatinization temperatures. These results suggested that the cultivars with low AC, small starch granule, and less B1 chains in amylopectin should be concerned in improving ECQ of inter-subspecies rice hybrids.

We have investigated the chemistry and Hg isotope fractionation during the aqueous reduction of HgII by oxalic acid, p-quinone, quinol, and anthraquinone-2,6-disulfonate (AQDS), a derivate of anthraquinone (AQ) that is found in secondary organic aerosols (SOA) and building blocks of natural organic matter (NOM). Each reaction was examined for the effects of light, pH, and dissolved O2. Using an excess of ligand, UVB photolysis of HgII was seen to follow pseudo-first-order kinetics, with the highest rate of ∼10-3 s-1 observed for AQDS and oxalic acid. Mass-dependent fractionation (MDF) occurs by the normal kinetic isotope effect (KIE). Only the oxalate ion, rather than oxalic acid, is photoreactive when present in HgC2O4, which decomposes via two separate pathways distinguishable by isotope anomalies. Upon UVB photolysis, only the reduction mediated by AQDS results in a large odd number mass-independent fractionation (odd-MIF) signified by enrichment of odd isotopes in the reactant. Consistent with the rate, MDF, and odd-MIF reported for fulvic acid, our AQDS result confirms previous assumptions that quinones control HgII reduction in NOM-rich waters. Given the magnitude of odd-MIF triggered via a radical pair mechanism and the significant rate in the presence of air, reduction of HgII by photoproducts of AQDS may help explain the positive odd-MIF observed in ambient aerosols depleted of HgII.

Rechargeable lithium-sulfur battery with a high theoretical energy density attracts intense attention, but it still often suffers from poor cyclability. Herein, a hierarchical porous carbon/graphene hybrid is designed to host sulfur for Li–S battery. The batteries exhibit good performances including a specific capacity of 1178 mA h g−1 after 70 cycles at 0.2C, a stable reversible capacity of 400 mA h g−1 after 600 cycles at 1.0C (80% retention). Extensive characterizations including adsorption-desorption isotherms, XRD, Raman spectroscopy, HAADF-STEM combining with soft XAS study the relationship between the structure and the performance of as-synthesized cathode material. The synergistic effect of graphene and hierarchical porous carbon provides the pathway of the electron and Li+ ingress/egress to react with the confined sulfur clusters, retard the loss of the polysulfide anions from the cathode and suppress the shuttle effect during long-term cycling process.

Electron transfer (ET) and Auger recombination (AR) processes in quantum dots (QDs) are key mechanisms for the advance of QD-based devices. However, it still remains a challenge to promote ET and suppress AR simultaneously. Here, we use in situ high-pressure ultrafast transient absorption spectroscopy to explore the impact of pressure on the ET between CdSe/ZnS and anthraquinone (AQ) and AR dissolved in cyclohexane. Remarkably, under compression, ET lifetimes are shorten, while suppression of AR lifetimes is present. The promotion of ET is attributed to the shortened distance between CdSe/ZnS and AQ induced by pressure. We rationalize that for the AR suppression, pressure may enhance the formation of an alloy layer at the core/shell interface. These findings indicate that compression is an effective approach to promote ET and suppress AR simultaneously. This study highlights a brand-new approach for modulating ET and AR and provides new routes toward QD-based applications.

Rice samples were collected at 560 sites in 15 provinces across China in areas without known point mercury (Hg) sources. Total mercury (THg) and methylmercury (MeHg) concentrations were analyzed in these rice samples for risk assessment. Relatively low THg and MeHg concentrations were found in the majority of the white rice samples with an overall mean of 4.74 (1.06–22.7) μg kg−1 and 0.682 (0.03–8.71) μg kg−1, respectively. The means (range of) THg concentration of rice in each geographical region were 5.23 (1.07–19.5) μg kg−1, 5.14 (1.06–17.2) μg kg−1, 4.45 (1.41–17.2) μg kg−1, 4.20 (1.48–19.4) μg kg−1, 3.49 (1.49–10.7) μg kg−1, and 4.53 (1.30–19.4) μg kg−1 in east, centre, south, southwest, northwest and northeast, China, respectively, and the corresponding values for MeHg concentrations were 0.898 (0.127–8.35) μg kg−1, 0.603 (0.207–2.48) μg kg−1, 0.516 (0.032–1.50) μg kg−1, 0.615 (0.050–5.03) μg kg−1, 0.704 (0.148–2.41) μg kg−1 and 0.565 (0.035–8.71) μg kg−1, respectively. Hg contents in rice across China were found to be at background levels. Both the probable daily intakes (PDIs) of inorganic Hg (IHg) and MeHg from rice consumption showed low risks for general population in the investigated regions. Keywords: Rice, Mercury, Methylmercury, Probable daily intake, Health risk

Background Blackberry postharvest diseases are caused by fungal pathogens, and treatment of fruits with edible, natural products could reduce the postharvest losses and contribute to food sustainability. Based on the hypothesis that inhibition of fungal pathogens will significantly extend the shelf-life of food products, the effects of natural antifungal agents on fungal pathogens were tested. Results Two pathogenic fungal isolates, Aspergillus japonicus and Gilbertella persicaria, from infected blackberry fruits were identified morphologically using scanning electron microscopy and confirmed by DNA sequence analysis. The inhibitory effects and synergistic action of natural antifungal agents against the two fungal isolates were investigated. The results obtained demonstrated that the natamycin, chitosan and ferulic acid exhibited significant antifungal activities against the tested strains based on the calculated minimum inhibitory concentration. The best antifungal activity was obtained using a combination of ferulic acid and natamycin, which generated a total synergistic effect on both tested strains with a fractional inhibitory concentration index of 0.281. Application of the selected agents on postharvest blackberry fruits reduced the rot ratio and weight loss and also increased fruit firmness. In addition, the shelf-life of fresh blackberry fruits was extended up to 12-15 days at 4 °C and 90 ± 5% relative humidity. Conclusion The combined utilization of ferulic acid and natamycin showed synergistic antifungal activity against two pathogenic fungal isolates, and extended the shelf life of fresh blackberry fruits up to 12-15 days. © 2018 Society of Chemical Industry.

Among cellulose-based materials, carboxymethyl cellulose (CMC) can be used as an alternative eco-friendly packaging material. However, the conservation of high stiffness and strength against hydration-induced decay of mechanical properties at a high humidity remains a fundamental challenge in such water-borne materials. Inspired by mussel adhesive proteins (adhesive) and nacre (brick-and-mortar structure), in this work, a bio-inspired multifunctional CMC composite was conjugated to dopamine (DA) and subsequently assembled with montmorillonite (MTM) to generate bio-inspired and layered nanocomposite films using a simple vacuum filtration-assisted assembly method. The modified CMC and composite films were comprehensively characterized, particularly with XPS and NMR. The conjugation of DA on CMC resulted in nanocomposites with an improved stability in the wet state and increased tensile strength (162.0 MPa) and elastic modulus (8.7 GPa) at a relative humidity of up to 90%. Thermogravimetric analysis and a horizontal flame test also showed that the nanocomposites possessed a high thermal stability and were able to self-extinguish immediately after removal of the flame. Therefore, the facile strategy developed in this work provides a promising approach to prepare biomimetic materials with excellent moisture resistance and flame retardancy, which have great potential for various applications.

Hetero-layered iron–nitrogen coordination between g-C3N4 and graphene nanomeshes was developed for superior electrocatalytic activity in the oxygen reduction reaction. Compared with the performance of g-C3N4 or atomic Fe embedded in g-C3N4 in the oxygen reduction reaction, the current density at −0.5 V of the two-dimensional hetero-hybrid of atomic Fe, g-C3N4 and graphene was enhanced 13 times, and the half-wave potential of the hybrid positively shifted to 0.278 V. The hybrid exhibited superior electrocatalytic activity with a 20 mV more positive half-wave potential, higher current density, better methanol tolerance and longer-term stability compared to commercial Pt–C. This enhancement originated from mesh-on-mesh exposed inter-layer bridged Fe–N4.1 coordination active sites between g-C3N4 and graphene, which favored a four-electron pathway accompanied by the improvement of the conductivity and mass transport. Superior performance, including a low charge–discharge voltage gap over 20 h of cyling, of the hybrid-based Zn–air battery was achieved. This strategy of the hetero-layered interfacial metal–nitrogen coordination between different 2D materials is a general approach to develop advanced electrocatalysts for sustainable energy applications.

Indica-japonica hybrid rice cultivars show great yield potential but poor eating quality and require more nitrogen (N) input relative to japonica rice. However, the effect of N levels on the eating quality of indica-japonica hybrid rice is little known. A field experiment was carried out to investigate the effects of four N levels on two indica-japonica hybrid rice cultivars (Yongyou12 and Yongyou17) differing in eating quality. The results showed that the contents of amylose chains and water-insoluble storage proteins, especially prolamin, increased largely under a high N level, leading to deterioration of the rice-eating quality, although a low N level (100 N kg/ha) had a less negative effect on the eating quality. Moreover, both of the indica-japonica hybrids had high ratios of inferior grains (IG), and the ratio of IG increased with the N level. Grain weight and the immature ratio of IG were reduced and increased with the N level, respectively, which are also factors for deterioration of the eating quality. The two cultivars differed greatly in the responses of eating quality to the N level, with Yongyou17 being more sensitive than Yongyou12. The current results indicated that a high N level deteriorates the eating quality of indica-japonica hybrid rice mainly due to a large increase of IG.

Plants will meet various abiotic stresses during their growth and development. One of the important strategies for plants to deal with the stress is involved in metabolic regulation, causing the dramatic changes of metabolite profiles. Metabolomic studies have been intensively conducted to reveal the responses of plants to abiotic stress, but most of them were limited to one or at most two abiotic stresses in a single experiment. In this study, we compared the metabolite profiles of barley seedlings exposed to seven abiotic stresses, including drought, salt stress, aluminum (Al), cadmium (Cd), deficiency of nitrogen (N), phosphorus (P) and potassium (K). The results showed that metabolite profiles of barley under these stresses could be classified into three groups: osmotic stresses (drought and salt); metal stresses (Al and Cd) and nutrient deficiencies (N, P and K deficiencies). Compared with the control, some metabolites (including polyamines, raffinose and pipecolic acid) in plants exposed to all abiotic stresses changed significantly, while some other metabolites showed the specific change only under a certain abiotic stress, such as proline being largely increased by osmotic stress (drought and salinity), the P-containing metabolites being largely decreased under P deficiency, some amino acids (lysine, tyrosine, threonine, ornithine, glutamine and so on) showing the dramatic reduction in the plants exposed to N deficiencies, respectively. The current meta-analysis obtained a comprehensive view on the metabolic responses to various abiotic stress, and improved the understanding of the mechanisms for tolerance of barley to abiotic stress.

Alkali‑oxygen cooking of lignocellulose offers lignin many structural properties and bioactivities for biorefinery. In this work, milled wood lignin (MWL) and alkali‑oxygen lignin (AOL) were isolated from rice straw and alkali‑oxygen black liquor, respectively. The lignin structure was characterized by spectroscopy and wet chemistry. Antioxidant activity of lignins was assessed by DPPH·and ABTS scavenging ability assay. Results showed the oxidization and condensation of lignin occurred during alkali‑oxygen cooking. The p-hydroxyphenyl was more easily removed from rice straw than guaiacyl and syringyl units. The ester or ether linkages derived from hydroxycynnamic acids, and the main interunit linkages, i.e. β–O–4′ bonds, were mostly cleaved. Lignin-xylan complex had high reactivity under alkali‑oxygen condition. Tricin, incorporated into lignin, was detected in MWL but was absent in AOL. Nitrobenzene oxidation showed MWL can well represent the protolignin of rice straw, and the products yield decreased dramatically after alkali‑oxygen cooking. AOL had higher radical scavenging ability than MWL indicating alkali‑oxygen cooking was an effective pathway for the enhancement of antioxidant activity of lignin.

In this work, the fluorescent CAU-1-(OH)2 was successfully exploited as a fluorescent probe for bismuth ion (Bi3+) in aqueous solutions, which is the first MOF-based fluorescent sensor for Bi3+ up to date. The MOF can exhibit bright green fluorescence in H2O for the intramolecular proton transfer process between the ligand and H2O molecule. In addition, the carboxylate and hydroxyl groups in the MOF can strongly coordinate with Bi3+. Accordingly, CAU-1-(OH)2 can selectively detect Bi3+ in water in 24 s. In addition, the limit of detection of this MOF was calculated to be 2.16 μM, superior to those of some traditional methods such as spectrophotometry and flow injection potentiometry.

In this work, a fundamental understanding of oxygen delignification distracted by dissolved lignin was investigated. In the new biorefinery model of shortening kraft pulping integrated with extended oxygen delignification process, increasing content of residual lignin in the original pulp could result in enhanced delignification efficiency, higher pulp viscosity and less carbonyl groups. However, the invalid oxygen consumption by dissolved lignin could be increased with the increase of process temperature and alkali dosage. The normalized ultraviolet absorbance (divided by absorbance at 280 nm) also showed that the content of chromophoric group in dissolved lignin decreased with oxygen delignification proceeded, both of which indicated that dissolved lignin could enhance the invalid oxygen consumption. Therefore, a conclusion that replacement of the liquor at the initial phase of oxygen delignification process would balance the enhancement of delignification efficiency and invalid oxygen consumption was achieved.

Large-scale synthesis of either single-metal atom catalyst or graphene from graphite direct exfoliation at high yield is quite challenging. Here we demonstrated a scalable electrochemical approach to synthesize few-layer graphene flakes and isolated Fe atoms at the same time. It was found that graphite could be expanded in FeCl4--based ionic liquid at a low potential of 2 V. Fe isolated onto graphene resulted from electrochemical reactions of FeCl4--based intercalates. After annealing at the presence of nitrogen source, atomic Fe isolation was kept and coordinated with nitrogen. The paintable atomic layer material exhibited superior oxygen reduction reaction performance to Pt/C. The catalytic activity could be enhanced 30 times per gram and 100 times per metal atom, if Fe-Nx/graphene was compared with Pt/C (20 wt.% Pt) on the basis of metal content.

The excited-state double proton transfer (ESDPT) process of dipyrido[2,3-a:3',2'-i]carbazole (DPC) in ethanol (EtOH) solvent is investigated using density functional theory (DFT) and time-dependent density functional theory (TDDFT). The computational results provide convincing evidence that proton transfer did not occur spontaneously for the DPC monomer due to the lack of hydrogen bonds. Interestingly, after adding EtOH to DPC, two intermolecular hydrogen bonds were formed in the ground-state, and the intermolecular hydrogen bonds were strengthened in the excited-state, as confirmed by comparing the changes in the primary bond parameters. In addition, the charge transfer was observed in the DPC-EtOH complex compared with the DPC monomer. In particular, a reliable ESDPT process occurs within the system upon photoexcitation, which was monitored by the formation and disappearance of characteristic peaks in the IR spectrum. All results adequately proved that the participation of EtOH exerts a remarkable effect on the ESDPT process. Overall, our work not only comprehensively elaborated the simultaneous mechanism of ESDPT but can also pave the way towards the design and synthesis of novel molecules.

A catalyst consisting of atomic iron embedded in a new hierarchical carbon matrix was synthesised, and this catalyst exhibited superior performance in CO2 electroreduction. Bamboo-like carbon nanotubes were catalytically grown by Fe3C nanocrystals on graphene co-doped with atomic iron and nitrogen by a new approach of electrochemical oxidation of graphene films in an FeCl4−-based ionic liquid followed by annealing. The highly selective generation of CO from CO2 was achieved at a low overpotential of 0.55 V with a maximum CO faradaic efficiency of ∼95% for over 12 h.

The effects of atomic electronegativity (O, S and Se atoms) on the excited-state intramolecular proton transfer (ESIPT) properties of three compounds (3-HF, 3-HTF and 3-HSeF) were systematically studied using the density functional theory (DFT) and time-dependent DFT (TD-DFT) methods. Furthermore, the antioxidant activities of the three compounds were evaluated using different parameters from the perspective of biological activities. The calculated results indicate that the generation of ESIPT is attributed to the excited-state intramolecular charge transfer owing to the change in electron density distribution on the frontier molecular orbitals and natural bond orbital (NBO) charge distribution of the O1 and O2 atoms at the S0 and S1 states. Moreover, 3-HTF shows the greatest red shift of the O1–H1 stretching peak and the lowest energy barrier at the S1 state among the three compounds, implying that 3-HTF would have the strongest intramolecular hydrogen bond at the S1 state, which is most beneficial for the occurrence of ESIPT. In addition, the decreased ionization potentials and energy gaps from 3-HF to 3-HTF and 3-HSeF means that the antioxidant activity of the compound would be enhanced along with the lowered atomic electronegativity. Interestingly, the lower ionization potentials and energy gaps of the compounds in keto forms suggest that the compound (3-HTF) easy to carry out ESIPT reaction would exhibit efficient antioxidant activity, which would establish the relationship between ESIPT reaction and antioxidant activity of the compound and provide a new notion for synthesizing more efficient antioxidants in experiments.

The T296V mutant of amorpha-4, 11-diene synthase catalyzes the abortive conversion of the natural substrate (E,E)-farnesyl diphosphate mainly into the acyclic product (E)-β-farnesene (88%) instead of the natural bicyclic sesquiterpene amorphadiene (7%). Incubation of the T296V mutant with (3R,6E)-nerolidyl diphosphate resulted in cyclization to amorphadiene. Analysis of additional mutants of amino acid residue 296 and in vitro assays with the intermediate analogue (2Z,6E)-farnesyl diphosphate as well as (3S,6E)-nerolidyl diphosphate demonstrated that the T296V mutant can no longer catalyze the allylic rearrangement of farnesyl diphosphate to the normal intermediate (3R,6E)-nerolidyl diphosphate, while retaining the ability to cyclize (3R,6E)-nerolidyl diphosphate to amorphadiene. The T296A mutant predominantly retained amorphadiene synthase activity, indicating that neither the hydroxyl nor the methyl group of the Thr296 side chain is required for cyclase activity.

Lignin, as a natural antioxidant, has a great potential to replace the chemosynthetic ones due to this material benefits of being biodegradable, eco-friendly, abundant and low-cost. However, the commonly-used lignins, such as acid, kraft and alkali lignins, have the poor antioxidant ability, and their antioxidative mechanism and kinetics remain poorly understood. Moreover, the understanding of the effect of polysaccharides in lignin-carbohydrate complex (LCC) on lignin antioxidant activity is also extremely insufficient. Herein, we isolated lignin and LCC from rice straw and its alkali-oxygen spent liquor to investigate their structure-antioxidant activity relationship and antioxidative mechanism. Experimental results illustrated that the alkali-oxygen treatment can significantly enhance the antioxidant activity of lignin. Demethoxylation, ring-opening and the cleavage of aryl ether bonds occur to lignin structure leading to the decrease of molecular weight, while the more stable condensed β-1', 5-5' and β-5' linkages maintain the thermostability of this antioxidant. The synergistic effect of adjacent methoxyl with phenolic hydroxyl is the key factor that endows lignin with the outstanding antioxidant activity. In contrast, oligosaccharides formed by alkali-oxygen treatment have a negative influence on the antioxidant activity of lignin. This work demonstrates that alkali-oxygen lignin is a promising antioxidant to replace chemosynthetic ones for polymeric materials.

In mercury (Hg) contaminated areas of Asia, human exposure to toxic methyl-Hg (MeHg) through a rice-based diet of locally produced crop may pose a health threat. Alternative cropping system to rice in such areas would be most desirable. In this study, corn, the leading cereal source in the world with large biomass, was demonstrated to accumulate an insignificant amount of MeHg from the soil in its edible portion compared to that in rice, suggesting corn being a very competitive alternative crop. By examining Hg stable isotope composition, Hg in the aerial parts of corn was found to be mostly from the atmosphere. Maize cropping worldwide is estimated to be a discemible sink of atmospheric Hg with approximately 44 Mg Hg accumulated in each growing season on a yearly basis, most of which is from foliar uptake of atmospheric Hg and this amount is comparable to litterfall Hg observed in North America and Europe. It is thus recommended to use corn as a replacement of rice in highly Hg-contaminated areas for remediation of Hg pollution in the food supply.

In this study, three donor-π-acceptor (D-π-A) type unsymmetrical porphyrin-based dyes have been designed and synthesized for dye-sensitized solar cells (DSSCs). The photophysical, electrochemical and photovoltaic properties of the dyes were successfully adjusted by using functionalized arylamines (triphenylamine or N, N-dimethyl-4-(acetylene)-aniline) as donor, porphyrin derivatives as conjugated π bridge, ethynyl-thiophene or ethynyl-thiophthene as π spacer and carboxylic acid as anchor group. Compared with the dye containing ethynyl-thiophene as π spacer, the dyes containing 2-ethynyl-6-methylthieno[3,2-b]thiophene as π spacer between the porphyrin macrocycle and the carboxylic acid anchoring group show broadened absorption spectra on TiO2 films and red-shifted absorption spectra in solution. The dye based on triphenylamine and 2-ethynyl-6-methylthieno[3,2-b]thiophene exhibited a power conversion efficiency (PCE) of 4.53% under simulated air mass 1.5 global sunlight. These results indicate that the introduction of 2-ethynyl-6-methylthieno[3,2-b]thiophene in the meso-positions of porphyrin dyes is an effective approach to improve the photovoltaic performance.

Lignin and lignin-carbohydrate complexes are important polymers for lignocellulosic biorefinery and functional materials, but those in ginkgo shells are not effectively analyzed and exploited. Based on this background, milled wood lignins (MWLML and MWLFZ) and lignin-carbohydrate complexes (LCCML and LCCFZ) were isolated from the shells of Ginkgo biloba L. cv. Damaling (ML) and Ginkgo biloba L. cv. Dafozhi (FZ) correspondingly, and were structurally characterized by comprehensive NMR spectroscopy. The results showed that ginkgo shells exhibited higher lignin (42%) and xylan (20%) content than general softwood species. Isolated MWLs were rich in guaiacyl units with the presence of ferulates and p-coumarates, and the molecular formula was C9H7.93O2.73(OCH3)0.81 and C9H7.87O2.76(OCH3)0.88 for MWLML and MWLFZ, respectively. Phenolic hydroxyl of MWLML (1.38 mmol/g) and MWLFZ (1.23 mmol/g) in ginkgo shells was much less than that in general softwoods, suggesting a higher etherification and condensation degree of ginkgo shells lignin, and &beta, 5&prime, &alpha, O-4&prime, and 4-O-5&prime, bonds were the main condensed structures. O-acetylated &beta, d-xylopyranoside and &beta, d-mannopyranoside were the main polysaccharides associated with lignin, and the acetyl groups frequently acylate the C2 and C3 positions. LCCML had more phenyl glycoside (0.035/Ar) and less &gamma, ester (0.026/Ar) linkages than LCCFZ.

The effects of lignin-combined manganese ion, iron ion, and lignin-combined iron and manganese on the decomposition of hydrogen peroxide were investigated. Elemental analysis and inductively coupled plasma-atomic emission spectrometry were used to analyze the chemical features of the lignin composites and the amount of metal ions present in the solution or adsorbed on lignin, respectively. The results showed that the main transition metal elements remaining in the precipitated lignin were Fe, Mn, and Cu. The hydrogen peroxide decomposition in the presence of lignin-combined transition metal was represented by pseudo-first-order kinetics, and the pseudo-first-order rate constant (kobs) of peroxide decomposition with lignin-combined iron was 0.0068 min-1, while it was 0.0063 min-1 in the presence of lignin-combined manganese. A synergistic effect of manganese and iron combined with lignin on peroxide decomposition was demonstrated, and a kobs value of 0.0053 min-1 was obtained. The mixed addition of magnesium sulfate (MgSO4), sodium silicate (Na2SiO3), and ethylene diamine tetraacetic acid disodium salt (Na2EDTA) resulted in an optimal reduction in peroxide decomposition when single lignin-combined metal ion existed. However, adding Na2EDTA alone had an optimal effect on the reduction of peroxide decomposition in the presence of lignin-combined iron and manganese, with a kobs value of 0.0004 min-1.

Graphitic carbon nitride (g-C3 N4 ) is traditionally obtained by thermal polycondensation of nitrogen-rich organic nonionic precursors. Herein, we provide a new and simple strategy for the synthesis of g-C3 N4 through direct thermal condensation of single protic guanidine salts with various anions. The thermal condensation process, and the structure and photophysical properties (optical properties, thermal stabilities, morphology and porosity, and photocatalytic activity) of the obtained g-C3 N4 materials are investigated intensively through thermogravimetric analysis, powder X-ray diffraction, X-ray photoelectron spectroscopy, UV/Vis diffuse reflectance spectroscopy, nitrogen adsorption isotherms, and photodegradation of Rhodamine B. The results reveal that during thermal condensation, the nitrogen-rich basic core in the guanidine salts serves as a carbon and nitrogen source to form the skeleton of g-C3 N4 , and the counter anions mediate the thermal condensation in situ and modify slightly the structure and properties of g-C3 N4 , even though they are not incorporated into the final structure. Among all g-C3 N4 materials, including the pristine g-C3 N4 from melamine, the g-C3 N4 derived from guanidine thiocyanate exhibits a high activity toward the photocatalytic degradation of Rhodamine B dye because of its relatively high surface area, enhanced absorption, small bandgap, and low photoluminescence intensity.

Ammonium polyphosphate–diatomite composite filler (APP-diatomite composite filler) was modified with silane coupling agent KH550 to improve the flame retardancy of filled paper. Cone calorimeter was used to analyze the heat and smoke releasing rates, as well as smoke toxicity of the filled paper. The distribution of the composite filler particles in paper and the morphology of the charred residues after combustion were investigated by scanning electron microscope (SEM), and the chemical structure of the charred residues was studied with fourier transform infrared spectroscopy (FTIR). Results show that the peak heat releasing rate (PHRR), total heat release (THR) and peak mass loss rate (PMLR) of the filled paper with the modified APP-diatomite decreased markedly, compared with those for the control paper, while the charred residue after combustion increased. In addition, the filled paper had an increased peak rate of smoke release (RSR) and increased total smoke release (TSR) and peak CO production rates, but a decreased peak CO 2 production rate. It was also found that part of the carbon element in the charred residue of the paper loaded with the modified APP-diatomite was in the forms of C=C=C, C≡C and C≡N, and the charred residue had a relatively more intact structure without apparent fiber breakage and longitudinal cracks.

Starch-based fixatives (SBF), specifically low molecular weight, highly-cationic starches (LHCS), have been reported to efficiently control dissolved and colloidal substances (DCS) in pulp suspensions, and to enhance paper strengths. However, as their degree of substitution (DS) was as high as 0.65, their preparation cost was very high. In this study, two products with lower DSs of just 0.08 (LHCS 0.08) and 0.22 (LHCS 0.22) were prepared and compared to a traditional polyamine (PA) fixative. It was found that the novel LHCSs interacted more readily with the anionic pulp fibers while the PA interacted more readily with the anionic DCS. Consequently, both LHCS 0.08 and LHCS 0.22 increased the paper strength more than the PA. Moreover, it was found that the LHCS 0.22 was most efficient in fixing the colloidal substances onto fibers, while the PA was most efficient in neutralizing the dissolved substances. We conclude that LHCS with DS as low as 0.22 can be used as a good fixative, however, starch with DS of only 0.08 is not efficient enough.

The data presented in this article are related to the research article entitled “Structure-antioxidant activity relationship of active oxygen catalytic lignin and lignin-carbohydrate complex” (Jiang et al.). It supplements the article with thermostability of milled wood lignin (MWL) and alkali-oxygen lignin (AOL), main substructures of lignin in rice straw, main products and yield of nitrobenzene oxidation of lignin-carbohydrate complexes (LCCs), Fourier transform infrared spectroscopy of LCCs, radical (ABTS·) scavenging ability of lignins and signal assignment of lignins and LCCs in nuclear magnetic resonance spectra (1H, 13C, 2D HSQC NMR). The dataset is made publicly available and can be useful for extending the structural and bioactive research and critical analyses of lignin and LCC. Keywords: Rice straw, Lignin, Lignin-carbohydrate complex, Structure, Antioxidant activity

Graft-versus-host disease (GVHD) of central nervous system (CNS) is a rare complication after allogeneic hematopoietic cell transplantation (allo-HSCT), which is easily misdiagnosed and has limited treatment and poor efficacy. In this study, we reported two children(1 case of severe aplastic anemia and 1 case of acute myeloid leukemia) who were subjected to the secondary haploid hematopoietic stem cell transplantation of another door after the first implantation failure. Two patients developed epileptic seizures during hematopoietic recovery. Peripheral blood and cerebrospinal fluid cytokines were detected and diagnosed as acute GVHD in the central nervous system. The cytokine elevation is mainly IL-6(IL-6 level in peripheral blood was 2276.25 pg/ml, and in cerebrospinal fluid was 2353.89pg/ml of case 1). We administered multiply consecutive plasmapheresis, intravenous infusion of tocilizumab combined with intrathecal injection of tocilizumab and dexamethasone. The epileptic symptoms of 2 cases are effectively controlled after the first dose. The IL-6 levels in peripheral blood and cerebrospinal fluid of both patients decreased significantly after 4(IL-6 level in peripheral blood was 6.74 pg/ml, and in cerebrospinal fluid was 195.72pg/ml of case 1) and 5 doses, respectively. Central nervous system aGVHD is prone to hematopoietic recovery after secondary transplantation; intrathecal injection of tocilizumab is safe and effective in the treatment of central nervous system aGVHD with elevated IL-6 mainly, which is worth further exploring. Figure. Figure. Disclosures No relevant conflicts of interest to declare.

Li3PO4 and Co3(PO[Formula: see text]8H2O precursors, precipitated within a micro reactor using ethyl alcohol as anti-solvent, are sintered to form nanosphere-like LiCoPO4. Even without carbon coating, the resulting sample with 2.1[Formula: see text]wt.% Li3PO4 existence presents surprisingly high initial discharge capacity (up to 164[Formula: see text]mAh/g and 787[Formula: see text]Wh/kg at 0.1C) and superior high rate performance (117[Formula: see text]mAh/g and 561[Formula: see text]Wh/kg at 5C).

Silk mask paper with different adsorbability was prepared by changing the beating degree of silk pulp and the basis weight of silk paper, and photocatalytic silk mask paper was prepared by loading nanometer titanium dioxide (nano-TiO2) on the silk mask paper, then degradation of formaldehyde by silk mask paper loading nano-TiO2 under daylight lamps and ultraviolet lamps were investigated, respectively. Results showed that silk mask paper could adsorb formaldehyde and had higher adsorption efficiency in the initial stage, and the adsorption/desorption equilibrium could be basically achieved in 60 minutes. The adsorption capacity of silk mask paper made from silk pulp with beating degree of 45 oSR was relatively low, and it increased with the increase of beating degree, but there was little change in adsorption when the beating degree of silk pulp exceeded 65 oSR. Under daylight lamps, 26.61 %, 31.42 % and 38.21 % of formaldehyde could be degraded in 180 minutes by silk mask paper loading 1 wt%, 3 wt% and 5 wt% nano-TiO2, respectively. However, under ultraviolet (UV) lamps, 46.23 %, 55.47 % and 66.38 % of formaldehyde could be degraded within the same time, respectively. More formaldehyde could be degraded by photocatalytic silk mask paper under UV lamps than under daylight lamps, and the more the load of nano-TiO2 on the silk mask paper, the higher the degradation rate of formaldehyde within the same time.

Two new soluble unsymmetrical zinc-phthalocyanine derivatives (PC-HY1, PC-HY2) with D-π-A structure bearing three tert-butylphenyl or tert-butylthienyl groups and cyanoacrylic acid groups were synthesized through a low-cost “anhydride” method. The photophysical, electrochemical and photovoltaic properties of the phthalocyanine derivatives were studied. The two phthalocyanine derivatives showed strong and broad absorption in the UV and red/near-infrared (IR) region, especially for PC-HY2. The electrochemical properties indicated that the two phthalocyanine derivatives are latent materials for dye-sensitized solar cells. Under the illumination of AM 1.5, 100 mW cm−2, dye-sensitized solar cells based on PC-HY1 and PC-HY2 showed power conversion efficiency (PCE) of 0.79% and 1.09%, respectively.

Flexible counter electrodes (CEs) are designed and fabricated by depositing the composite film of carbon materials (carbon aerogel, carbon black, and active carbon) and poly(tetrafluoroethylene) on...

A developmentally stunted mutant (dsm1) of Arabidopsis, isolated from an EMS mutant screen, had a pleiotropic phenotype, including repressed germination, retarded growth, delayed flowering, and impaired fertility. Additionally, dsm1 had a lifespan of approximately 160 days, which was more than twice the lifespan of the wild type (Col-0). Fine morphological and anatomical characters, such as the shoot apical meristem, root apical meristem, seed shape, and seed surface, were obviously altered in dsm1. We found that both abscisic acid and zeatin riboside levels were significantly greater in dsm1 than in Col-0 at all stages of development, while the levels of indole-3-acetic acid and gibberellins varied by age. The expressions of some abscisic acid-related genes were higher in dsm1 than in Col-0. These data indicate that DSM1 may play a general role in plant growth and development.

A simultaneous self-Q-switched and mode-locked diode-pumped 946 nm laser by using a Cr,Nd:YAG crystal as gain medium as well as saturable absorber is demonstrated for the first time as we know. The maximum average output power of 751 mW with a slope efficiency of 18.38% is obtained at an intra-cavity average peak power intensity of 4.83 x 10(6) W/cm(2). Under this circumstance, the repetition rate of Q-switched envelopes is 9.63 kHz and the pulse width is about 460 ns. Almost 100% mode-locked modulation depth is obtained at all time in the experiment process whether the incident pump power is low or high. The repetition rate of mode-locked pulses within a Q-switched envelope is 135.13 MHz and the mode-locked pulse width is within 600 ps. The laser produces high-quality pulses in TEM00-mode in the simultaneous self-Q-switched and mode-locked experiment. (C) 2007 Elsevier B.V. All rights reserved.

By a facile reaction route, we synthesized five technologically important transition metal carbide nanoparticles including cubic NbC, TaC, VC, hexagonal WC and MoC at relatively low temperatures. Here, in this rapid reaction process, we choose an organic reagent melamine and transition metal oxides as reaction precursors. The experimental results indicate that melamine is a highly efficient carburization reagent, and the metal oxides are completely converted into the corresponding carbides at relatively low temperatures. It is found that NbC, TaC, VC and WC are composed of fine nanoparticles having average size of 7, 13, 5 and 18 nm with a fairly narrow size distribution, respectively. The potential reaction mechanism between melamine and transition metal oxides and some new characteristics involved in this route are presented and discussed.

A dramatic increase of chlorophyll (Chl) degradation occurs during senescence of vegetative plant organs and fruit ripening. Although the biochemical pathway of Chl degradation has long been proposed, little is known about its regulatory mechanism. Identification of Chl degradation-disturbed mutants and subsequently isolation of responsible genes would greatly facilitate the elucidation of the regulation of Chl degradation. Here, we describe a nonyellowing mutant of Arabidopsis (Arabidopsis thaliana), nye1-1, in which 50% Chl was retained, compared to less than 10% in the wild type (Columbia-0), at the end of a 6-d dark incubation. Nevertheless, neither photosynthesis- nor senescence-associated process was significantly affected in nye1-1. Characteristically, a significant reduction in pheophorbide a oxygenase activity was detected in nye1-1. However, no detectable accumulation of either chlorophyllide a or pheophorbide a was observed. Reciprocal crossings revealed that the mutant phenotype was caused by a monogenic semidominant nuclear mutation. We have identified AtNYE1 by positional cloning. Dozens of its putative orthologs, predominantly appearing in higher plant species, were identified, some of which have been associated with Chl degradation in a few crop species. Quantitative polymerase chain reaction analysis showed that AtNYE1 was drastically induced by senescence signals. Constitutive overexpression of AtNYE1 could result in either pale-yellow true leaves or even albino seedlings. These results collectively indicate that NYE1 plays an important regulatory role in Chl degradation during senescence by modulating pheophorbide a oxygenase activity.

Brassinosteroids (BRs) play an essential role in plant growth and development, and have been implicated in many physiological responses. However, little is known about the role of BRs in the plant response to oxidative stress. In this study, we identified a novel insertion allele (det2-9) of the DET2 gene in Arabidopsis based on molecular, physiological and genetic approaches. We found that the det2 mutant exhibited an enhanced resistance to oxidative stress. The enhanced oxidative stress resistance in det2 plants was correlated with a constitutive increase in superoxide dismutase (SOD) activity and increased transcript levels of the defence gene catalase (CAT). To our knowledge, these results demonstrate, for the first time, that loss-of-function mutations in the DET2 gene lead to an enhanced oxidative stress resistance in Arabidopsis. A general explanation is that the long-term BR deficiency in the det2 mutant results in a constant in vivo physiological stress that, in turn, activates the constitutive expression of some defence genes and, consequently, the activities of related enzymes.

We report here a new sort of partially-crystallized carbon materials obtained from the reducing reactions between alkalis carbonate (M2CO3 M=Li, K, Na) and active metals such as Li, Mg, Al and Ga. The chemical reactions are carried out at the temperature range of 600-900 degrees C and under the argon ambience. The typical reaction can be represented as follows:K2CO3 +4Li=2Li(2)O+K2O+C. X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and energy-dispersive X-ray fluorescence (EDAX) characterizations reveal evidently that the obtained final black powder products are carbon materials with partially-crystallized structure. In addition, we also investigate the electric performance of the obtained carbon materials, the initial discharge capacity and initial charge capacity have been measured respectively as high as 1267 mAh/g and 736 mAh/g. (c) 2007 Elsevier B.V. All rights reserved.