查看更多>>摘要：? 2022 Elsevier B.V.Microemulsion fuels have involved oil, alcohol, surfactant, and cosurfactant/amphiphilic molecule. A system of chemical reactions takes place between phase boundaries. Palm oil as vegetable oil has been assessed as a renewable resource. So, before applying microemulsions, an immiscible mixture (palm oil and ethanol) needs to be evaluated for the chemical activity, such as suspected defects. This study aimed: to determine the presence of defect products that occurred at the phase boundary of the palm oil:ethanol mixture, and to determine the influence of amphiphilic chitosan/Zeolite LTA toward the palm oil:ethanol mixture. This research was carried out through: (1) preparation of zeolite LTA, (2) synthesis of amphiphilic chitosan/Zeolite LTA, (3) application of phase boundary reactions in an immiscible mixture of palm oil:ethanol. The results have shown that the synthesis of amphiphilic chitosan/Zeolite LTA was successful as confirmed by XRD, FTIR, and SEM. Furthermore, the application of the reaction between oil:ethanol has shown that there were defect products as a result of chemical mixtures and interactions that occurred. This study has proven that the defect activity can occur in the liquid phase.
查看更多>>摘要：? 2022 Elsevier B.V.Perennial herbaceous crops (PHC) diversity requires the proper selection of genotypes with high biomass production. These crops can be harvested at different stages of the vegetation period. The objective of the study was to determine the yield and biomass quality of seven PHC genotypes, including three dicotyledon plants (Helianthus tuberosus L., Helianthus salicifolius A. Dietr, Silphium perfoliatum L.) and four monocot plants (Miscanthus × giganteus J.M. Greef & M. Deuter, M. sinensis ((Thunb.) Andersson), M. sacchariflorus ((Maxim.) Hack.), Spartina pectinata Bosc ex Link) during double harvest (June and October) in three vegetation periods. The highest yield in the first harvest (June) was obtained from S. perfoliatum (7.7 Mg ha?1 y?1 d.m.). However, in the second harvest (October), the yield of this genotype was not so high, and the total yield from two harvests (June + October) was 11.6 Mg ha?1 y?1 d.m. The highest yield from two harvests was obtained from S. pectinata (13.5 Mg ha?1 y?1 d.m.). The yields of PHC harvested twice in one growing period, obtained in the third year of the study, were lower compared with the yields obtained in the first and second years. It was shown that the moisture and nitrogen contents in biomass obtained in the first harvest were higher in all genotypes compared with the second harvest. It was also found that dicotyledon plants contained more ash and lignin than grasses. However, the grasses had higher contents of cellulose and hemicelluloses. The above information is important to customers and end-users of PHC.
查看更多>>摘要：? 2022Eucommia ulmoides rubber (EUR) is a high-molecular polymer of trans-1,4-polyisoprene, conventionally synthesized by a sequential condensation of isopentenyl diphosphates to its isomer of dimethylallyl diphosphate in trans con?guration. The extraction methods for EUR generally include mechanical method, alkali extraction, solvent extraction, and microbial method. Compared with others, microbial method can obtain higher purity EUR and retain its original appearance furthest with less environmental pollution as well as less production cost, implying that it might become the primary extraction technology. EUR has dual characteristics of rubber and plastic. The utilization of EUR is highly dependent on the crystallinity and crosslinking degree which can be modified by physical or chemical methods, to help producing the EUR industrial products that can have multi-functionalities. The objective of this review is to investigate the recent insights of the biosynthesis, extraction, the structure and properties, the modi?cation as well as application of EUR to promote the research and utilization of EUR, to meet the requirements of various engineering applications. EUR is expected to partially substitute natural rubber with broad prospects for development and utilization.
查看更多>>摘要：? 2022 The AuthorsDryness triggers soil degradation processes and land abandonment in the south Mediterranean environment. Becoming unsuitable for food crops, it can be usable by low-iLUC risk biomass crops able to withstand prolonged dry periods due to drought-resilience traits and high biomass yield. The present experiment ascertained the biomass dry matter yield (DMY), water use efficiency (WUE) and water footprint (WF) by modulating soil water availability of six warm-season perennial grasses in the semiarid Mediterranean for two consecutive growing seasons. Two ecotypes of giant reed (Arundo donax L., ARCT and ARMO, respectively), one ecotype of African fodder cane (Saccharum spontaneum L. subsp. aegyptiacum (Willd.) Hack., SAC) and three hybrids of Miscanthus (the commercial M. × giganteus J.M. Greef, Deuter ex Hodk., Renvoize - M×G, and two new seed-based hybrids, GNT9 and GNT10, respectively) were subjected to 100%, 50% and 0% of maximum crop evapotranspiration (ETm) restoration supplied during summer months. Crop water use (CWU) differed among crops, growing seasons and irrigation regimes, and significantly influenced DMY, WUE and WF. ARCT, ARMO and SAC had higher DMY and WUE, and lower WF than Miscanthus hybrids. Among Miscanthus, the new seed-based hybrids outperformed the M×G in all examined parameters. Genotypic response in DMY, WUE and WF by varying the CWU had different trends and rates of change. The relationship between WUE and WF combining data of all genotypes, growing seasons and irrigation regimes followed an exponential decay; it underlined the importance to select for crops with high resource use efficiencies to reduce the water required per ton of biomass.
查看更多>>摘要：? 2022 Elsevier B.V.The electro-physical properties of raw, alkali and oxidatively modified jute fabrics were investigated as complex phenomena of the interactions between the fabrics’ chemical composition, carboxyl group content, crystallinity, structural characteristics, moisture sorption, and frequency of the electric field. At 80% relative air humidity, chemically modified jute fabrics have 38–179% and 1.7–5.4 times higher dielectric loss tangent and effective relative dielectric permeability compared to unmodified. To further improve these properties, fabrics were treated with CuSO4 and Cu-based nanoparticles were in situ synthesized on their surfaces by reduction. A few smaller agglomerates of Cu-based nanoparticles were observed across the alkali modified fabric's surface, while smaller irregularly shaped and larger agglomerates were distributed over the oxidatively modified fabric's surface. Regardless of the type of synthesized nanostructures (metallic Cu, copper oxide (Cu2O or CuO) or their mixtures), excellent fabrics’ effective relative dielectric permeability is guaranteed. Precisely, exploitation in specific conditions that contribute to copper reduction will make jute fabrics able to store 21–163 times more energy from an external electric field than before the exploitation, which will extend their lifetime. On the other hand, with increasing the total content of Cu after the reduction and formation of agglomerates of Cu-based nanoparticles, the movements of cellulose, hemicelluloses, and lignin molecules become difficult resulting in lower energy dissipation within the chemically modified than within unmodified fabric. Applied chemical modification and coating with Cu-based nanoparticles enables designing fabrics with predictable electro-physical properties, which is very important from the application point of view.
查看更多>>摘要：? 2022 Elsevier B.V.Plant-based phytotoxins play an important role in plant-plant interaction and are of great promise for the development of bioherbicide. In this study, screening of essential oils from six different Curcuma rhizomes identified black turmeric (Curcuma caesia Roxb.) oil as an efficient growth inhibitor in wheatgrass coleoptile bioassay (IC50 57.1 μg/mL). The phytotoxic efficacy of this oil was further confirmed through the dose dependent (10.0–300.0 μg/mL) inhibition of germination, coleoptile and radicle growth of wheatgrass seeds in water medium (IC50 176.7, 90.6 and 93.0 μg/mL respectively) and the pre-germinated seeds in agar medium. Activity-guided fractionation and purification of the crude oil identified curzerenone, a major furanosesquiterpene in this oil as the most active phytotoxin (IC50 13.0 μg/mL in coleoptile bioassay; 188.3, 34.7 and 36.7 μg/mL respectively in water medium). Structure-activity relationship study indicated the importance of all the functional groups for its phytotoxicity. A significant contribution by the oxygenated monoterpenes towards oil phytotoxicity was also evidenced. Though inhibitory efficacy of the oil was comparatively weak in soil, a profound activity through aerial diffusion was observed against germination and/or growth of fresh and pre-germinated wheatgrass seeds (IC50 1.4–6.2 mg/L air). The study also confirmed the uptake of active phytotoxins with no detectable transformation by the seeds in water and their persistence in the soil for at least one and half months. Further, its applicability was demonstrated through an efficient post-emergence growth inhibition (IC50 37.0–81.4 μg/mL) of bermudagrass weed in water and agar medium.
查看更多>>摘要：? 2022 Elsevier B.V.The special molecular structure and properties of cellulose restrict its resource utilization. In this work, two kinds of common inorganic salt hydrates (ZnBr2·RH2O and FeCl3·RH2O) were used to pretreat microcrystalline cellulose (MCC) by magnetic stirring method at temperatures below 80 °C. It was found that while high temperatures could shorten the dissolution time of MCC, while inorganic salt hydrates with either low water (ZnBr2·3.5H2O and FeCl3·5H2O) or high water (ZnBr2·5H2O and FeCl3·8H2O) content can prolong the dissolution time of MCC. The reactivity of regenerated cellulose (RC) after dissolution was evaluated by enzyme hydrolysis reaction. Moreover, ZnBr2·4H2O and FeCl3·6H2O have better pretreatment effect. The structure and surface morphology of MCC before and after pretreatment were investigated by XRD, FT-IR, SEM, AFM and TGA. The MCC was converted from cellulose Ⅰ to cellulose II through the pretreatment. With the extension of dissolution time, the strength of hydrogen bond and thermal stability of RC were both slightly weakened, Moreover, the crystallinity and degree of polymerization (DP) of RC decreased, and the surface morphology of RC was more rougher, more uneven and dispersed compared with the smooth and compact MCC. The adsorption rate curves showed that RC-ZnBr2·4H2O was more conducive to the adsorption of cellulase, thereby accelerating the rate of RC hydrolysis. Furthermore, ZnBr2·4H2O is a well reusable pretreatment solvent that can maintain a good pretreatment effect on cellulose after five cycles.
查看更多>>摘要：? 2022 Elsevier B.V.The objective of this study was to identify the flavonoid chemical compositions of Dalbergia odorifera heartwood extracts, to investigate their correlation with heartwood color, for establishing an evaluation method for quantifying the quality of the heartwood. The results showed that the heartwood color parameters, L* and b*, were significantly correlated with the total flavonoid contents of the extracts (correlation coefficients of ?0.93 and ?0.86, respectively). Furthermore, 50 flavonoid components in the extracts were identified by ultra-high-performance liquid chromatography–mass spectrometry (UHPLC–MS), and a method for determining the contents of 16 major components was established. Among the major components, liquiritigenin, dalbergin, calycosin, daidzein and fisetin had significant negative correlations with both L* or b*. This study provides a basis for the establishment of evaluation methods to determine the quality of Dalbergia odorifera heartwood.
查看更多>>摘要：? 2022 Elsevier B.V.Continual crop monitoring and harvesting at optimum time to ensure maximum economic returns is a huge challenge for farmers having small landholdings in Indo-Gangetic plains where Mentha arvensis is a popular cash crop. The present study evaluates different hyperspectral indices for phenotyping the canopy of M. arvensis winter crop (cv. CIM-Kranti) for detection of optimum harvest time using ground-based plant traits. Field experiments were conducted during mid-crop growth stage to late crop growth period for two consecutive years using hyperspectral camera (400–940 nm) to acquire images representing the spectral reflectance of crop canopies. Hyperspectral vegetation indices (HVIs) derived from these images were further evaluated with an aim to identify those hyperspectral indices showing a strong correlation to measured crop parameters. Out of the 18 HVIs, 4 HVI's i.e. photochemical reflectance index (PRI), carotenoids reflectance index (CRIr), hyperspectral normalized difference vegetation index (HNDVI) and plant senescence reflectance index (PSRI) were recognized as potential predictors for sucker traits (weight and length) and thereby indicators of optimum harvesting time for M. arvensis winter crop (cv. CIM-Kranti) cultivated primarily to produce suckers for crop propagation. Our results show promise for the development of non-destructive methods for the detection of optimum harvest time using crop reflectance. This study holds importance for the menthol mint farmers, who cultivate the crop for suckers during winter months for additional income generation.
查看更多>>摘要：? 2022 Elsevier B.V.Atratum and ruzi grasses have illustrated high potential for methane production through anaerobic digestion. To enhance the utilization of these grasses for the production of renewable biogas, liquid hot water pretreatment was applied to break down various lignocellulose matter, in particular, hemicellulose. After pretreatment under optimal conditions (200 °C for 15 min), more than 90% of hemicellulose was removed and solubilized in the form of a clear hydrolysate. Xylose was the primary sugar in the hydrolysate, appearing in several forms, and acting as the major substrate for methane production. Total xylose yields for the atratum and ruzi grasses were 58 and 74 mg/g TS respectively. The pretreated atratum and ruzi substrates were evaluated for methane production resulting in an increased methane yield of at least 14%, and more than 70% biodegradability. This work demonstrates the potential for atratum and ruzi grasses to be used as a viable alternative to other energy crops such as Napier grass.
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