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Heterogeneous structures have attracted extensive attention in the area of microwave absorption because they can promote interfacial polarization and thus enhance microwave absorption. Many efforts...

In this study, we designed a new flame retardant to improve the fire safety performance of epoxy resin (EP). Graphitic carbon nitride (g-C3N4) was derived from melamine through a solid-phase reaction, after which nickel ammonium phosphate nanowires (NiNH4PO4·H2O) were grown on the g-C3N4 using a hydrothermal method. The resulting material (g-C3N4/NiNH4PO4·H2O) was a halogen-free flame retardant containing effective flame-retardant elements such as C, N, P, and Ni. Subsequently, g-C3N4/NiNH4PO4·H2O was added to EP to test its fire resistance and mechanical properties. When the amount of g-C3N4/NiNH4PO4·H2O was 5 phr (per hundred resin), the peak of smoke production rate and peak heat release rate of the EP composite were reduced by 35.42 and 70.4 %, respectively, compared to those of pure EP. Meanwhile, the limiting oxygen index of the EP composite was enhanced to 30.0 % from 24.5 % (pure EP). Finally, the flame-retardant mechanisms of the gas phase and condensed phase were explored.

In this paper, a kind of fluorescent anti-counter feiting acrylate pressure-sensitive adhesive (PSA) label was prepared using 7-hydroxycoumarin and acrylate monomer. First,7-hydroxycoumarin was rea...

In this study, a hybrid material with band‐shaped nickel ammonium phosphate monohydrate (NiNH4PO4.H2O) (ANP) and reduced graphene oxide (RGO) was devised by the one‐pot method. This material is a novel, efficient and non‐halogen flame retardant and smoke suppressant. Based on the characterization results, a crystal growth and thermal decomposition process of ANP is proposed, which proves that it has flame retardancy and smoke suppression in the gas phase and condensed phase. When the amount of ANP/RGO was 15 phr (per hundred parts of resin), the total smoke production, peak smoke production rate, total heat release and peak heat release rate of poly(vinyl chloride) (PVC) composite were 49.76%, 59.46%, 47.48% and 69.94% lower respectively than those of pure PVC. Meanwhile, the tensile strength of the PVC composite increased by 6.74%. The results show that ANP/RGO improves the fire safety performance, smoke suppression and mechanical properties of PVC composites. The significant improvement in fire safety performance is mainly attributed to the dilution of combustible gases with ammonia and water generated by the decomposition of ANP/RGO during combustion, and the phosphide in the condensed phase made the residual char crosslinked and denser to protect the substrate more effectively. © 2020 Society of Chemical Industry

The mango is one of the most valuable and appealing tropical fruits due to its color, aroma, tasteful remarkable flavor, and nutritive value, however, improving the yield and quality of mango is an urgent goal in order to combat global population growth. The application of amino acids and a micronutrient mixture might improve the yield and quality features but further research is still required in arid regions. To study the combined effect of a micronutrient mixture (MM) and amino acids (AA) at different rates, twenty-seven Fagri Kalan mango trees (15 years old) were carefully selected. The foliar application effect of MM and AA on vegetative growth, total chlorophyll, leaf chemical constituents, productivity, and the fruit quality of mango trees (cv. Fagri Kalan) was investigated. The findings revealed that the investigated growth measurements and leaf chemical contents, as well as the fruiting aspects and the fruit quality improved significantly due to the application of MM and AA. A higher application rate of the micronutrient mixture (2 g L−1) in combination with the highest amino acid concentration (2 mg L−1) was the most effective combination that increased the yield, total soluble solids (TSS), total sugars (TS), and total carbohydrates by 28.0%, 3.0%, 5.8% and 15.0%, respectively, relative to untreated plants. The relationship between such characteristics revealed a strong positive correlation (0.80–0.95), confirming the importance of these materials in increasing the yield and quality of mangoes. Thus, using doses of MM and AA as a foliar spray four times during each growing season is recommended under similar environmental conditions and horticulture practices used in the current experiment.

This paper demonstrates a rational protocol for the synthesis of ultrasmall bimetallic alloy nanoparticles (FeCo, FeNi, and NiCo

Pitaya (Hylocereus genus) is a popular plant with exotic and nutritious fruit, which has widespread uses as a source of nutrients and raw materials in the pharmaceutical industry. However, the potential of pitaya peel as a natural source of bioactive compounds has not yet fully been explored. Recent advances in metabolomics have paved the way for understanding and evaluating the presence of diverse sets of metabolites in different plant parts. This study is aimed at exploring the diversity of primary and secondary metabolites in two commercial varieties of pitaya, i.e., green pitaya (Hylocereus undatus) and red pitaya (Hylocereus polyrhizus). A total of 433 metabolites were identified using a widely targeted metabolomic approach and classified into nine known diverse classes of metabolites, including flavonoids, amino acids and its derivatives, alkaloids, tannins, phenolic acids, organic acids, nucleotides and derivatives, lipids, and lignans. Red pitaya peel and pulp showed relatively high accumulation of metabolites viz. alkaloids, amino acids and its derivatives, and lipids. Differential metabolite landscape of pitaya fruit indicated the presence of key bioactive compounds, i.e., L-tyrosine, L-valine, DL-norvaline, tryptophan, γ-linolenic acid, and isorhamnetin 3-O-neohesperidoside. The findings in this study provide new insight into the broad spectrum of bioactive compounds of red and green pitaya, emphasizing the valorization of the biowaste pitaya peel as raw material for the pharmaceutical and food industries.

With the development of flexible electronic devices, various requirements for flexible conductive materials have been put forward to. However, the self-healing, mechanical and conductive properties of the flexible materials are poor. Therefore, it is important to prepare self-healing materials with good mechanical and conductive properties. In this paper, room temperature self-healing and conductive composites based on imine reversible covalent bond were prepare by introducing of the carbon nanotube and carbon black. The self-healing, mechanical and conductive properties of the composites were studied. And the structure of the composites was also characterized. The experimental results showed that the mechanical strength and the electrical resistivity of composites were 6.6 MPa and 108 Ω·m, respectively. The composites have excellent room temperature self-healing properties through the reversible exchange of imine bond, and the healing efficiency of mechanical properties and the electrical properties can reach 96% and 93%, respectively. At the same time, the self-healing mechanism was put forward to. In addition, the composites can be recovered by solution recovery and hot pressing.

Background Elucidating the candidate genes and key metabolites responsible for pulp and peel coloration is essential for breeding pitaya fruit with new and improved appeal and high nutritional value. Here, we used transcriptome (RNA-Seq) and metabolome analysis (UPLC-MS/MS) to identify structural and regulatory genes and key metabolites associated with peel and pulp colors in three pitaya fruit types belonging to two different Hylocereus species. Result Our combined transcriptome and metabolome analyses suggest that the main strategy for obtaining red color is to increase tyrosine content for downstream steps in the betalain pathway. The upregulation of CYP76ADs is proposed as the color-breaking step leading to red or colorless pulp under the regulation by WRKY44 transcription factor. Supported by the differential accumulation of anthocyanin metabolites in red pulped pitaya fruit, our results showed the regulation of anthocyanin biosynthesis pathway in addition to betalain biosynthesis. However, no color-breaking step for the development of anthocyanins in red pulp was observed and no biosynthesis of anthocyanins in white pulp was found. Together, we propose that red pitaya pulp color is under the strict regulation of CYP76ADs by WRKYs and the anthocyanin coexistence with betalains is unneglectable. We ruled out the possibility of yellow peel color formation due to anthocyanins because of no differential regulation of chalcone synthase genes between yellow and green and no detection of naringenin chalcone in the metabolome. Similarly, the no differential regulation of key genes in the carotenoid pathway controlling yellow pigments proposed that the carotenoid pathway is not involved in yellow peel color formation. Conclusions Together, our results propose several candidate genes and metabolites controlling a single horticultural attribute i.e. color formation for further functional characterization. This study presents useful genomic resources and information for breeding pitaya fruit with commercially attractive peel and pulp colors. These findings will greatly complement the existing knowledge on the biosynthesis of natural pigments for their applications in food and health industry.

Soil degradation due to global warming, water scarcity and diminishing natural resources negatively impacts food security. Soil fertility deterioration, particularly phosphorus (P) deficiency, remains a challenge in the arid and semi-arid regions. In this study, field experiments were conducted in different geographical locations to investigate the effects of organic amendments coupled with P fertilization and irrigation on soil physical-chemical properties, and the growth, yield and quality of wheat. Application of P fertilizers combined with organic amendments mitigated soil salinity, increased organic matter content, available water, hydraulic conductivity and available macronutrients, but decreased soil bulk density. Application of organic amendments slightly increased total Cd, Ni and Pb in soil, but Cd and Ni concentration was below allowable limits whilst Pb reached a hazardous level. Soil P fractions were significantly increased with the combined application of mineral P and organic amendments irrespective of salinity and irrigation. Crop growth yield and quality of wheat improved significantly in response to the integrated application of mineral P and organic amendments. In conclusion, the combination of mineral P sources with organic amendments could be successfully used as a cost-effective management practice to enhance soil fertility and crop production in the arid and semi-arid regions stressed with water scarcity and natural resource constraints.

Avocado (Persea americana Mill.) is an economically important crop because of its high nutritional value. However, the absence of a sequenced avocado reference genome has hindered investigations of secondary metabolism. For next-generation high-throughput transcriptome sequencing, we obtained 365,615,152 and 348,623,402 clean reads as well as 109.13 and 104.10 Gb of sequencing data for avocado mesocarp and seed, respectively, during five developmental stages. High-quality reads were assembled into 100,837 unigenes with an average length of 847.40 bp (N50 = 1725 bp). Additionally, 16,903 differentially expressed genes (DEGs) were detected, 17 of which were related to carotenoid biosynthesis. The expression levels of most of these 17 DEGs were higher in the mesocarp than in the seed during five developmental stages. In this study, the avocado mesocarp and seed transcriptome were also sequenced using single-molecule long-read sequencing to acquired 25.79 and 17.67 Gb clean data, respectively. We identified 233,014 and 238,219 consensus isoforms in avocado mesocarp and seed, respectively. Furthermore, 104 and 59 isoforms were found to correspond to the putative 11 carotenoid biosynthetic-related genes in the avocado mesocarp and seed, respectively. The isoform numbers of 10 out of the putative 11 genes involved in the carotenoid biosynthetic pathway were higher in the mesocarp than those in the seed. Besides, alpha- and beta-carotene contents in the avocado mesocarp and seed during five developmental stages were also measured, and they were higher in the mesocarp than in the seed, which validated the results of transcriptome profiling. Gene expression changes and the associated variations in gene dosage could influence carotenoid biosynthesis. These results will help to further elucidate carotenoid biosynthesis in avocado.

Chitosan-modified zinc hydroxystannate (ZHS-CS) was synthesized using the cations of the biomaterial chitosan (CS) and ion replacement strategy. A ZHS-CS and reduced graphene oxide (rGO) hybrid flame retardant (ZHS-CS/rGO) was synthesized for use in flexible poly (vinyl chloride) (PVC). Scanning electron microscopy images indicated that ZHS-CS and rGO were evenly dispersed in ZHS-CS/rGO without agglomeration. Fourier transform infrared spectroscopy results showed that rGO was fully reduced. The flame-retardant and mechanical properties of PVC composites were investigated using the limiting oxygen index (LOI), a cone calorimeter, and mechanical equipment. By replacing one-fifth of the zinc ions in ZHS by chitosan cations to obtain Sn-4Zn-1CS/rGO, the ZHS-CS/rGO was found to improve PVC composite performance. The total heat release and total smoke release of PVC/Sn-4Zn-1CS/rGO were reduced by 24.2 and 40.0 %, respectively, from those of pure PVC.

This work investigates the application of polyphosphazene (PZN) modified magnesium hydroxide (MH) crosslinked by boric acid (BA) (MH-PZPI-BA) for simultaneous flame retardant, smoke suppression and mechanical properties enhancement of ethylene-vinyl acetate (EVA) nanocomposites. The MH-PZPI-BA was prepared by a PZN nano-coating made from hexachlorocyclotriphosphazene and branched polyethyleneimine (bPEI) was deposited onto the MH followed by BA cross-linking bPEI. Then MH-PZPI-BA was incorporated into EVA, and the properties were examined. Compared with pure EVA, the peak heat release rate and total heat released decreased by 82.7% and 44.2%, respectively. The MH-PZPI-BA has an excellent performance in reducing the smoke, CO, and CO2 production rates. The "tortuous path" effect of the boron nitride of in-situ growth hindered the transfer of volatile products, and led to the formation of a compact and robust char layer in condensed phase during combustion, in the combustion process of EVA/MH-PZPI-BA. The tensile strength and elongation at break are improved by 26.1% and 33.5%, respectively.

Land degradation due to soil salinity and sodicity is a serious concern in arid ecosystems. Despite the importance of conservation tillage in carbon sequestration and improving soil properties, its effect on saline-sodic soils under amendment application remains unknown. Therefore, the present study aimed to explore the combined effects of inorganic (sulfuric acid and gypsum) and organic (vermicompost) soil amendments and tillage systems (zero, reduced and deep tillage) on saline-sodic soil properties and wheat productivity. Deep tillage with vermicompost application significantly improved soil physical and chemical properties compared with control. Interestingly, integration between deep tillage and vermicompost decreased soil salinity and sodicity by 37% and 34%, respectively, compared with zero tillage and unamended soils. The application of vermicompost surpassed chemical amendments in the improvement of saline-sodic soils and consequently increased the growth and yield of wheat, provided that deep tillage was used as a suitable tillage system. Although deep tillage reduced soil organic carbon, application of vermicompost not only compensated this reduction, but also significantly increased soil organic carbon. This confirms the potential of combined deep tillage and vermicompost as a method for environmentally reclaiming saline-sodic soils.

Sweet basil (Ocimum basilicum var. Genovese) is an important medicinal herb and is considered to be a moderately salt-tolerant plant. However, little is known about the effect of biochar on enhancing its salinity tolerance. The response of basil plant to water salinity (8 dS m−1, NaCl salinity) and three levels of biochar i. e., C, BC1, and BC2 (0, 1, and 2 % by weight) was investigated, as was the effect of biochar on NH3 volatilization kinetics. Irrigation of basil plants with saline water reduced the plant height, fresh weight, and dry weight by 27 %, 18 %, and 17 % in comparison to tap water. The application of biochar to saline irrigated basil caused remarkable increases in all the recorded growth parameters. Water salinity reduced N, P, and K availability and shoot concentrations. When applied, BC1 and BC2 under saline conditions increased shoot concentrations of N by 42 % and 67 %; P by 40 % and 70 % and K by 15 % and 50 %. Water salinity increased the concentrations of proline and phenolic compounds by 15 and 70 %, respectively; moreover, it reduced the total chlorophyll by 10 %. Water salinity reduced the oil yield by 15 %. The overall oil yield was increased by 18 and 38 % as a result of BC1 and BC2 application. The salinity of irrigation water increased the NH3 volatilization and reduced its half-life by 34 %. On the other hand, biochar reduced NH3 volatilization and increased its half-life. Biochar improved the growth and yield of basil plants by improving the efficiency of photosynthesis and the absorption of essential nutrients. It also had a role in reducing the concentrations of biochemical substances produced under salt stress. Therefore, using biochar is a good strategy for reducing NH3 volatilization and enhancing soil quality and plant productivity under saline irrigation.

Fatty acids are important components of the avocado mesocarp, so a better understanding of how their change during fruit development will contribute to improving the quality of avocado fruits and their nutritional value. The changes in fatty acids, lipid droplets, and expression of some key genes and regulators participating in late glycolysis and fatty acid biosynthesis were analyzed at different stages of the development of avocado mesocarp. The total fatty acid contents of the avocado mesocarp increased during fruit development, with an increase by a factor of seven (from 1,628.04 to 11,116.30 mg/100 g dry weight) in the late stage of fruit maturation, this was confirmed by the changes observed in the lipid droplets. The composition of the main fatty acids varied at four developmental stages of fruit development. Palmitic, palmitoleic, oleic, and linoleic acid contents generally increased during fruit development, reaching maxima at Harvest, with percentages of total fatty acids of 50%, 9%, 31%, and 8%, respectively. Meanwhile, the amount of PaWRI1, PaACP4-2, and PapPK-β1 expressed consistently increased by up to 4-fold during fruit development. This comprehensive analysis has indicated that the changes in the expressions of PaWRI1, PaACP4-2, and PapPK-β1 were consistent with those in the total fatty acid contents, so they might have key roles in the accumulation of oil in the avocado mesocarp.

We studied the morphological characteristics, nutritional quality, and the bioactive compounds in fruits of two avocado accessions, RN-7 and RN-8, produced in Hainan province, China. Edible and non-edible parts of the fruit (pulp and seed) were compared to evaluate their possible contribution to improve the sustainability of the food and pharmaceutical industries. The basic characteristics evaluated were moisture, ash, total lipid, fatty acid composition, soluble sugars, titratable acid, soluble protein, and minerals. We also measured the concentrations of six types of bioactive compounds; total phenolics, flavonoids, tannin, ascorbic acid, tocopheryl acetate, and carotenoids. Our analyses of the nutritional compositions demonstrated that the pulp of the RN-7 and RN-8 proved to be rich in moisture, total lipid, and soluble protein. The seed, in turn, had higher soluble sugar, titratable acidity, sodium, potassium, calcium, iron, copper, and zinc contents. Other nutritional compositions (ash, magnesium, and manganese) had little differences between the pulp and seed of avocado fruit. With regard to the contents of bioactive compounds, the seed was superior to the pulp in the contents of total phenolics, flavonoids, and tannin. Regarding the concentrations of ascorbic acid, tocopheryl acetate, and total carotenoids, the highest values were found in the pulp. The results of fatty acid compositions displayed that the palmitic, palmitoleic, stearic, oleic, and linoleic acid contents of the pulp were higher than those of the seed, while myristic and arachic acid had higher contents in the seed.