查看更多>>摘要：Chitosan/lignin-containing cellulose nanofibrils (CS/LCNF) biocomposites were prepared by a facile and green method that combined hydrothermal pretreatment, mechanical fibrillation, and dry casting. LCNFs were isolated from switchgrass with various lignin contents, and their effects on the transparency, micromorphology, mechanical properties, interfacial compatibility, thermal stability, surface wettability, and barrier properties of the CS/LCNF biocomposites were comprehensively investigated. Their transparency was affected by changing the lignin and cellulose contents, as well as the order degree of cellulose. The hydrophobic micro/nano-lignin particles with the optimum contents (33.8%) coated on CNFs or embedded their networks prompt the dispersion of LCNF in CS matrices and enhance interfacial interaction of CS and LCNF. This synergistically improved the mechanical properties and thermal stability of CS/LCNF biocomposites. CS/LCNF8 maintained a ductility of 503% and showed a tensile strength that was 46.7% higher than that of CS/CNF, as well as a T-max and WCA that were 2.6 degrees C and 11.06 higher, respectively. Furthermore, CS/LCNF8 displayed a more competitive OTR (0.20 cc/(m(2) day)) than those of pure chitosan, mechanically-fibrillated CNFs, carboxymethylated CNFs, and TEMPO oxidized CNF/CS films at the same ratio. This study provides promising environmentally-friendly biocomposite films with outstanding comprehensive performance for green food packaging.
Gongora, Benhurtde Souza, Samuel Nelson MelegariBassegio, DoglasSantos, Reginaldo Ferreira...
10页
查看更多>>摘要：Safflower oilseed needs to be studied in detail in relation to the production of biodiesel and its application in engines to be an alternative to commercial biodiesel used around the world. The aim of this study is to compare safflower biodiesel with commercial biodiesel in terms of emissions and performance of an engine using blends biodiesel (B11, B15, B30, and B100). Commercial biodiesel consists of soybean oil and fat. The tests were performed on a single-cylinder, four-stroke, naturally aspirated, and direct-injection diesel engine at four engine loads with a constant engine speed of 3000 rpm. The comparison shows that safflower biodiesel has relatively closer fuel properties to commercial biodiesel than those of diesel oil. The engine power was less affected by increasing engine loads and increasing safflower biodiesel blends compared to commercial biodiesel. Safflower B11 reduced the specific consumption by 2% in relation to diesel (D100) at a load of 3000 W. Safflower biodiesel B11 showed lower carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxide (NOx), and exhaust gas temperature (EGT) compared to commercial biodiesel at high engine loads. The use of safflower biodiesel and commercial biodiesel blend B11 reduced NOx emissions by 15% at a high load of 3000 W. Therefore, safflower biodiesel is a promising alternative to diesel, although it has a higher production cost.
查看更多>>摘要：Sorghum straw, as an organic solid-waste, has a high biomass yield and is rich for xylan and glucan, making it a promising candidate for the production of value-added xylooligosaccharides and glucose. To streamline the biorefinery processes, the edible gluconic acid was used for xylooligosaccharides production and sorghum straw material pretreatment in this study. Firstly, response surface methodology was employed to maximize the yield of xylooligosaccharides, achieving a maximum xylooligosaccharide yield of 50.3% with 7.5% gluconic acid at 168 degrees C for 35 min; furthermore, the XOS and calcium gluconate can be co-prepared as feed additives. Meanwhile, the lignocellulosic entanglement of sorghum straw can be effectively deconstructed by acidic hydrolysis of gluconic acid and an enzymatic hydrolysis yield of 90.8% was subsequently achieved using pretreated sorghum straw solids. These findings show that gluconic acid pretreatment is able to effectively enhance the value of hemicellulose and cellulose from sorghum straw.
查看更多>>摘要：Arsenic (As) is toxic to living organisms at high concentrations. Utilization of an industrial non-edible oilseed crop like Ricinus communis L. (castor) for revegetation and phytoremediation of As-contaminated land can be highly beneficial. Although a lot of research has been conducted on castor, little is known about As toxicity and tolerance mechanisms in this bioenergy crop. In the present study, genome-wide transcriptional analysis was performed using RNA sequencing (RNA-Seq) to identify differentially expressed genes in As-tolerant and As sensitive castor genotypes in response to As(V) treatment. RNA-Seq data showed a differential expression pattern for stress-related genes between WM (tolerant) and GCH 2 (sensitive) genotype in response to 200 mu M As (V) treatment. A total of 19 DEGs (13 up and 6 downregulated) and 7157 DEGs (4093 up and 3064 down regulated) were identified in leaves of 200 mu M As(V)-treated WM and GCH 2 genotypes, respectively. Expression of genes associated with metal transport such as ZIP1, ZIP4, ZIP5, NRAMP3, metal chelators (MT-2, MT-3, PCS, NAS), photosynthesis responsive genes corresponding to Chl a-b binding proteins, RuBisCO small subunit and protein low PSII accumulation 3 were downregulated in GCH 2 whereas expression of these genes were either maintained or upregulated in WM in response to 200 mu M toxicity. Expression level of genes involved in As uptake and transport such as phosphate transporters, aquaporins, and mitochondrial dicarboxylate transporter (DIT1, DIT2.1) were upregulated in 200 mu M As(V)-treated sensitive genotype GCH 2 but maintaind in WM.
查看更多>>摘要：In this research paper, we endeavor to publish our work on non-acrylamide based flocculant which, does not threaten any acrylamide release and thus is inherently safer. A novel cationic graft copolymer Poly-diallyldimethylammoniumchloride grafted Gum Ghatti [GGt-g-P(DADMAC)] was synthesized using a 'micro-wave assisted' technique. Both GGt and DADMAC are biodegradable and non toxic in nature. The intended grafting was confirmed through standard physicochemical techniques. The synthesized graft copolymer was studied as a flocculant in various minerals and nanoparticle suspensions through standard 'Jar test' and 'settling test' protocols in various pH and temperature ranges. The simple proposition used to conceive this work was that the GGt-g-P(DADMAC) being positively charged due to the grafted chains aids the flocculation of the negatively charged nano-suspensions. This proposition has been experimentally verified by flocculation studies, with strong interrelation among grafting parameters. The results indicated that this novel graft copolymer is a superior flocculant to Gum ghatti and the commercially available ALUM and can be further studied towards commercial use.
查看更多>>摘要：Fine roots distribution and dynamics (production, mortality, and longevity) significantly impact the crop soil ecosystems. However, the spatial distribution and dynamics of cotton (Gossypium hirsutum L.) fine roots under film-mulched drip irrigation are poorly understood. The present study aims to characterize these distributions and dynamics measured using a minirhizotron technique and the influence of soil conditions. The non-uniform distribution of soil moisture and salinity may lead to the differences of root length density (RLD) distribution. A clear decreased trend for the average RLD was observed in the shallow soil layer due to high localized salinity accumulated after brackish water irrigation. There existed a clear high soil moisture content strip at depth which may lead to a high RLD peak in the 95-100 cm soil layer. Average live root production was characterized by a very high rate during the initial growth stage followed by a decline after budding, which in turn was followed by a slight increase during boll opening. The average number of new roots was highest during the initial growth stages, decreasing after the budding stage. Thinner roots in the deep soil had shorter lifespans than those in shallow soil. Our study indicated that the minirhizotron technique can be used reliably as an in situ, nondestructive method for estimating cotton fine roots distribution and dynamics under film-mulched drip irrigation. To evaluate cotton fine root distribution and dynamics under film-mulched drip irrigation more accurately, a cotton root system architecture model could be parameterized in space and time based on the minirhizotron observations.
查看更多>>摘要：Porous carbon spheres have drawn extensive attention owing to their excellent chemical stability and high surface area. However, the lack of mesopores and the high cost and complex preparation process limit their application. Herein, the interconnected hierarchical porous carbon spheres (HPCS-X-Y) from sodium lignosulfonate are synthesized by simple spray drying and carbonization-activation without template agents and crosslinking agents. The as-prepared HPCS-X-Y exhibits ultrahigh specific surface area (3402 m(2).g(-1)), large pore volume (2.46 cm(3).g(-1)), and well-developed macro-meso-microporous structure. When used as adsorbent for VOC removal and electrode material for supercapacitors, HPCS-X-Y shows excellent dichloromethane adsorption capacity (181 mg.g(-1)) and satisfactory specific capacitance (236.2 F.g(-1) at 0.2 A.g(-1)), respectively. Furthermore, it has been found that adsorption and electrochemistry performance of HPCS-X-Y are closely related to porous structure. Namely, micropores provide abundant adsorption sites for adsorbate molecule/electrolyte ion, resulting in high adsorption capacity/specific capacitance, while the mesopores together with the macropores offer fast transport channels for adsorbate molecule/electrolyte ion, which plays an important role in high adsorption efficiency, outstanding capacitance retention and low internal resistance. The outcomes of this work supply foundational references for the design of hierarchical porous carbon spheres and the high-value utilization of industrial lignin.
查看更多>>摘要：As more and more bamboo materials have been used for buildings, the bamboo creep property deserves more explorations because it is important to structural design and plays a critical role in serviceability of structure. In this study, the creep mechanism of bamboo over a wide range of scales from microstructure and bending flexural property to creep behavior were investigated. Firstly, the gradient functions of different vascular bundle distribution directions were obtained. The average value of gradient index n was respectively 2.16 and 0.29 when x axis ranged from different directions. Secondly, the flexural property test under different loading directions were analyzed. There were two groups, one group (O-T) was the fiber-rich outer culm wall in tension side, the other group (O-c) was the fiber-rich outer culm wall in compression side. It was concluded that Group O-T showed larger MOR and smaller MOE than Group O-C. In addition, the total energy consumed of Group O-T was larger than Group O-C, while the elastic energy was smaller. Thirdly, the creep property under different loading directions and humidity were examined, which is unique because no research about the bamboo creep performance under different humidity conditions has been completed according to the literature review. The creep deflection of Group O-T was larger than Group O-C whatever constant humidity or variable humidity was used. The relative creep of Group O-T was smaller than Group O-C under high humidity (90% RH) and variable humidity (30% RH-90% RH-30% RH), while larger under low humidity (30% RH). Compared to bamboo-based products, the stress level was more sensitive on the creep property of bamboo, and the anti-creep property of bamboo was lower than bamboo-based products.
查看更多>>摘要：Plastics are versatile and cost-effective materials with a variety of functionalities. Their non-biodegradability, accumulation in landfills and natural habitats, physical problems for wildlife resulting from ingestion or entanglement in debris, leaching of chemicals and transfer to humans are concerns of greater magnitude, however. In this regard, plastic replacing materials are warranted. A possible respite is seen in agriculture that feeds the world but a significant portion of crops exists as biomass or the parts that can't be used as food by humans. Agriculture biomass such as corn stalk, wheat straw, rice straw and soy stalk offers a viable source of cellulose that has excellent potential to replace plastics. Herein, the benefits of agriculture biomass and its prospects for cellulose-based biodegradable products are highlighted. The use of agriculture biomass further offers a unique value-added proposition to the agriculture industry and farmers to capitalize on their byproducts to increase the profitability of their operations. The Earth, and its current and future generations, will benefit immensely with this cost-effective and environmentally sustainable solution to curb the ills associated with plastics.
Sahoo, KamalakantaKhatri, PoonamKanwar, AkankshaSingh, Hari P....
12页
查看更多>>摘要：Energy crops grown on marginal lands offer an alternative supply of renewable resources while avoiding competition with food crops and supporting feed crops. To sustainably grow energy crops, the economic and environmental impacts of various crop management practices such as the adoption of cover crops, fertilization rates, harvesting methods and its end use applications for animal feed or biofuels should be investigated. In this study, we investigated the life cycle analysis (LCA) and economic evaluation of growing two energy crops (energy cane, and napier grass) on the marginal lands with three fertilizer treatments (0, 100, and 200 kg N ha (-1)), and with a cover crop (clover, Trifolium incarnatum L) in the southeastern United States (US). Energy crop was harvested once a year in the late fall for biofuel applications, while the Napier grass was harvested twice a year: first harvested early in spring for animal feed and later harvested in the fall for biofuel application. Experimental field data such as biomass yield, crop management practices, farm inputs, and carbon stored in the soil, were determined to assess the global warming potential and the delivered cost of each energy crop. Napier grass had lower global warming (GW) impacts and biomass delivery costs, 34-153 kg CO2 eq. per oven-dry metric ton (ODMT) and $51-$57 perODMT, respectively than that of energy cane. However, both the energy crops provided carbon sequestrations (-17 and -232 kg CO2 eq. ODMT-1) and thus net GW impact varied between 51 and (-14) kg CO2 eq. ODMT-1 based on the treatments. When the napier grass was harvested for both biofuel and fodder applications, the overall GW impacts and the delivered costs were reduced. Therefore, energy crops can be grown in marginal lands for increased carbon sequestration while reducing the GW impacts of energy crops for biofuel production. The integrated environmental and economic analyzes further demonstrated that the energy crop delivered costs and GW impacts could be further reduced, if the energy crops can be utilized for both biofuel and feed applications.
NSTL
Elsevier