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The incorporation of different types of buffer layers has demonstrated to improve the efficiency of Cu_2ZnSnS_4 (CZTS) thin film solar cells. The materials tested as buffer layers were Cadmium Sulphide (CdS), Zinc Sulphide (ZnS) a...
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The incorporation of different types of buffer layers has demonstrated to improve the efficiency of Cu_2ZnSnS_4 (CZTS) thin film solar cells. The materials tested as buffer layers were Cadmium Sulphide (CdS), Zinc Sulphide (ZnS) and Cadmium Zinc Sulphide (Cd_(7.23)Zn_(2.77)S_(10)). The effect of the buffer layer and the absorber layers on the structural, morphological and optical properties of the films was studied. As grown CZTS thin films made with SILAR method were annealed at 550 °C in the sulfur atmosphere for 60 min to improve the crystallinity of the material. X-ray diffraction (XRD) and Raman studies confirm the formation of kesterite structure in CZTS thin film. CdS, ZnS and Cd_(7.23)Zn_(2.77)S_(10) thin films also confirm crystalline nature with crystallite sizes being 9 nm, 13 nm and 14 nm respectively. Leaf, flower and petal−like morphologies of CdS, ZnS and Cd_(7.23)Zn_(2.77)S_(10) thin films respectively have been confirmed by Field Emission Scanning Electron Microscopy (FESEM). The electrical properties of the completed CZTS solar cells were also examined. From the obtained J-V characteristic curves upon illumination of the heterojunction solar cells, we calculated the power conversion efficiency to be 0.76%, 1.00% and 1.24% for the FTO/ZnO/ZnS/CZTS/Ag, FTO/ZnO/CdS/CZTS/Ag and FTO/ZnO/Cd_(7.23)Zn_(2.77)S_(10)/CZTS/Ag respectively.
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Background The unique ‘mandarin jacket’ leaf shape is the most famous trait of Liriodendron chinense and this characteristic gives L. chinense aesthetic and landscaping value. However, the underlying regulatory mechanism of gene...
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Background The unique ‘mandarin jacket’ leaf shape is the most famous trait of Liriodendron chinense and this characteristic gives L. chinense aesthetic and landscaping value. However, the underlying regulatory mechanism of genes involved in the leaf development of L. chinense has remained unclear. Methods Based on transcriptome data of leaves at different developmental stages from L. chinense, we identified differentially expression genes (DEGs) functioning in leaf development. A candidate gene named LcCUC2-like (LcCUC2L) had high similarity in sequence with Arabidopsis thaliana CUC2, and used for further research. We isolated the full-length LcCUC2L gene and its promoter from L. chinense. Subsequently, we analyzed the function of the LcCUC2L gene and its promoter activity via transformation into A. thaliana. Results In this study, we found that the LcCUC2L and AtCUC2 are homologous in sequence but not homologous in function. Unlike the role of AtCUC2 in leaf serration and SAM formation, the LcCUC2L mainly regulates cotyledon development and rosette leaf number. Histochemical β-glucuronidase (GUS) staining revealed that LcCUC2L was expressed in the cotyledons of A. thaliana seedlings, indicating that the LcCUC2L may play a role in cotyledon development. Ectopic expression of LcCUC2L resulted in long, narrow cotyledons without petioles, abnormal lamina epidermis cells and defective vascular tissue in cotyledons, and these results were consistent with the LcCUC2L expression pattern. Further analysis showed that overexpression of LcCUC2L also induced numerous rosette leaves. Also, LcCUC2L and other related genes showed a severe response in L. chinense by introducing exogenous auxin stimulation, partly revealed that LcCUC2L affects the leaf development by regulating the auxin content. Conclusions These results suggest that LcCUC2L may play a critical role in leaf development and morphogenesis in L. chinense, and our findings provide insight into the molecular mechanisms of leaf development in L. chinense.
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As an important agronomic trait, inclination of leaves is crucial for crop architecture and grain yields. To understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 (lc2, three alleles) mutant w...
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As an important agronomic trait, inclination of leaves is crucial for crop architecture and grain yields. To understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 (lc2, three alleles) mutant was identified and functionally characterized. Compared to wild-type plants, lc2 mutants have enlarged leaf angles due to increased cell division in the adaxial epidermis of lamina joint. The LC2 gene was isolated through positional cloning, and encodes a vernalization insensitive 3-like protein. Complementary expression of LC2 reversed the enlarged leaf angles of lc2 plants, confirming its role in controlling leaf inclination. LC2 is mainly expressed in the lamina joint during leaf development, and particularly, is induced by the phytohormones abscisic acid, gibberellic acid, auxin, and brassinosteroids. LC2 is localized in the nucleus and defects of LC2 result in altered expression of cell division and hormone-responsive genes, indicating an important role of LC2 in regulating leaf inclination and mediating hormone effects.
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Aluminum-based materials are widely used, but they are easily corroded and contaminated in some harsh conditions. Now, fabricating anti-wetting coatings on aluminum-base materials is a promising way to solve the above problems. In...
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Aluminum-based materials are widely used, but they are easily corroded and contaminated in some harsh conditions. Now, fabricating anti-wetting coatings on aluminum-base materials is a promising way to solve the above problems. In this work, a two-step method is developed to fabricate a hierarchical leaf-like superamphiphobic PTFE/CuO coating on 6061Al substrate, and it is simple, economical and environmentally friendly. The resultant coating is repellent to many liquids, such as tap water, ink, tea water, milk, H2SO4 solution (pH 3), NaOH solution (pH 10), ethylene glycol and glycerol. All contact angles of these liquids on the PTFE/CuO coating are more than 150 degrees, and water sliding angles are less than 10 degrees. Importantly, the results of the selfcleaning, adhesion, chemical stability and corrosion resistance tests indicate that the PTFE/CuO coating could protect the 6061Al substrate from corrosion and pollution. Furthermore, after the UV, thermal stability and mechanical stability tests, the PTFE/CuO samples are still be superhydrophobic, which suggests that 6061Al substrate with the PTFE/CuO coating could be applied in harsh conditions. In sum, the method is especially suitable to large-scale industry production and promising for corrosion protection and functional applications of aluminum-based materials.
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Uniform and monodisperse boehmite (y-AlOOH) nanosheets with a thickness of less than 20 nm have been prepared by the hydrothermal treatment of amorphous boehmite. XRD and FTIR analysis showed that boehmite nanosheets have uniform ...
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Uniform and monodisperse boehmite (y-AlOOH) nanosheets with a thickness of less than 20 nm have been prepared by the hydrothermal treatment of amorphous boehmite. XRD and FTIR analysis showed that boehmite nanosheets have uniform and high degree of crystallinity. SEM micrographs indicated that boehmite has a leaf-like morphology with high anisotropy (with a length of 0.25- 1 nm and a width of 50-100 nm).
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Copper oxide is widely used to obtain superhydrophobic surfaces due to its special micro/nano-structures and properties. However, there are few studies on a leaf-like CuO superhydrophobic coating by direct thermal oxidation of Cu ...
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Copper oxide is widely used to obtain superhydrophobic surfaces due to its special micro/nano-structures and properties. However, there are few studies on a leaf-like CuO superhydrophobic coating by direct thermal oxidation of Cu on 6061Al substrate. In this work, there is a simple and low-cost method including chemical replacement, thermal oxidation and low-energy-modification with stearic acid. The resultant coating is super-hydrophobic and oleophilic with water contact and sliding angles of 157. 3 degrees +/- 0. 5 degrees and 3. 6 degrees +/- 1, respectively. Additionally, it has low adhesion and excellent self-cleaning performances, whose corresponding mechanical analyses are conducted to theoretically discuss that stable micro/nano-structures and trapped air pockets could effectively influence the interfacial adhesion. Importantly, after tape-peeling, sandpaper-abrasion, and chemical stability tests, the coating still keeps superhydrophobic. Especially, in 3.5 wt% NaCl aqueous solution, compared with the corrosion current density of bare 6061Al substrate (7.18 x 10(-7)A/cm(2)), that of the SHP CuO coating (0.77 x 10(-7)A/cm(2)) decreases obviously. In sum, the method is especially suitable for large-scale industrial production of a stable superhydrophobic coating on Al alloys.
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Epimedium L. (Berberidaceae, Ranales), a perennial traditional Chinese medicinal herb, has become a new popular landscape plant for ground cover and pot culture in many countries based on its excellent ornamental characteristics a...
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Epimedium L. (Berberidaceae, Ranales), a perennial traditional Chinese medicinal herb, has become a new popular landscape plant for ground cover and pot culture in many countries based on its excellent ornamental characteristics and, distinctive and diverse floral morphology. However, little is known about the molecular genetics of flower development in Epimedium sagittatum . Here, we describe the characterization of EsSVP that encodes a protein sharing 68, 54, and 35% similarity with SVP, AGAMOUS-like 24 (AGL24) and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1) in Arabidopsis , respectively. Quantitative RT-PCR (qRT-PCR) indicated that EsSVP transcripts were principally found in petiole and leaf tissues, with little expression in roots and flowers and no in fruits. The highest EsSVP expression was observed in leaves. The flowering time of 35S::EsSVP in most Arabidopsis thaliana and in all petunia plants was not affected in both photoperiod conditions, but 35S::EsSVP 5# and 35S::EsSVP 1# Arabidopsis lines induced late and early flowering under long day (LD, 14 h light/10 h dark) and short day (SD, 10 h light/14 h dark) conditions, respectively. The 35S::EsSVP Arabidopsis produced extra secondary inflorescence or floral meristems in the axils of the leaf-like sepals with excrescent trichomes, and leaf-like sepals not able to enclose the inner three whorls completely. Moreover, almost all transgenic Arabidopsis plants showed persistent sepals around the completely matured fruits. Upon ectopic expression of 35S::EsSVP in Petunia W115, sepals were enlarged, sometimes to the size of leaves; corollas were greenish and did not fully open. These results suggest that EsSVP is involved in inflorescence meristem identity and flowering time regulation in some conditions. Although, the SVP homologs might have suffered functional diversification among diverse species between core and basal eudicots, the protein functions are conserved between Arabidopsis / Petunia and Epimedium .
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In rapeseed (Brassica napus L.), leaf margins are variable and can be entire, serrate, or lobed. In our previous study, the lobed-leaf gene (LOBED-LEAF 1, BnLL1) was mapped to a 32.1 kb section of B. napus A10. Two LMI1-like genes...
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In rapeseed (Brassica napus L.), leaf margins are variable and can be entire, serrate, or lobed. In our previous study, the lobed-leaf gene (LOBED-LEAF 1, BnLL1) was mapped to a 32.1 kb section of B. napus A10. Two LMI1-like genes, BnaA10g26320D and BnaA10g26330D, were considered the potential genes that controlled the lobed-leaf trait in rapeseed. In the present study, these two genes and another homologous gene (BnaC04g00850D) were transformed into Arabidopsis thaliana (L.) Heynh. plants to identify their functions. All three LMI1-like genes of B. napus produced serrate leaf margins. The expression analysis indicated that the expression level of BnaA10g26320D determined the difference between lobed- and entire-leaved lines in rapeseed. Therefore, it is likely that BnaA10g26320D corresponds to BnLL1.
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The effect of the use of sandwich-like polyaniline (S-PANI) nanocomposites in CO2 gas-separation membranes was investigated. S-PANI nanocomposites were synthesized via a two-step dispersion polymerization method. The first step wa...
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The effect of the use of sandwich-like polyaniline (S-PANI) nanocomposites in CO2 gas-separation membranes was investigated. S-PANI nanocomposites were synthesized via a two-step dispersion polymerization method. The first step was to manufacture a leaf-like polyaniline (L-PANI), which was used in the next step as a 2D template to synthesize the S-PANI. SEM images show that a three-layer sandwich-like structure of the S-PANI was successfully synthesized. ATR-FTIR measurements revealed that the S-PANI has a structure with conductive PANI layers on both sides of the L-PANI template. Furthermore, the N-2 and CO2 adsorption isotherms illustrate that S-PANI is much more attractive to CO2 than N-2 because of the amine functional groups of S-PANI. Hence, the CO2/N-2 separation performance of the ethylene vinyl acetate (EVA) copolymer membrane was successfully enhanced by the addition of the S-PANI nanocomposite. The CO2/N-2 selectivity of the membrane increased from 6.8 to 32.5 with a 3-wt% loading of S-PANI within the EVA matrix. The results show that 2D S-PANI could feasibly be used for CO2 gas membrane separation. (C) 2021 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.
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Inspired by natural branching systems such as tree canopy, leaves, plant root, river basins, mammalian circulatory and respiratory systems, branching networks have been suggested for electronic component cooling. However, previous...
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Inspired by natural branching systems such as tree canopy, leaves, plant root, river basins, mammalian circulatory and respiratory systems, branching networks have been suggested for electronic component cooling. However, previous studies of tree-like branching networks have focused on symmetric structures although most natural tree-like branching systems are asymmetric. Furthermore, leaf-like branching networks have been rarely used and discussed. A three-dimensional model was formulated to compare the flow and heat transfer characteristics of symmetric/asymmetric tree-like branching networks and symmetric/asymmetric (offset) leaf-like branching networks. Results show that the influence of the asymmetry is very small for tree-like branching network at low branching number. Offset in leaf-like branching networks can reduce pressure drop significantly while maintaining maximum temperature difference between the inlet and outlet of the flowing fluid.
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