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The performance of polymer solar cells is known to be critically dependent on the characters of the charge extraction layers. In this work, an efficient electron extraction layer (EEL) is developed by doping saccharin into precursor of ZnO. It shows that the introduction of saccharin helps to passivate defects in ZnO EEL and polish the interfacial contact, which lead to efficient charge transport and collection processes, suppressed charge recombination loss, and increased light photon utilization. In poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b;4,5-b′]dithiophene-2,6-diyl-alt-(4-(2-ethylhexyl)-3-fluorothieno[3,4-b]thiophene-)-2-carboxylate-2–6-diyl)]:[6,6]-phenyl C71-butyric acid methyl ester (PTB7-Th:PC71BM) based cells, over 10% enhancement of power conversion efficiency (PCE) is obtained compared to that of the reference cell with pristine ZnO as EEL. This work proves that the strategy of precursor additive has potential to prepare highly efficient EEL for polymer solar cells.

A CuCeZr composite oxide (Cu-Ce0.8Zr0.2O2) was prepared via microwave-assisted co-precipitation method and employed in syngas production from dry reforming of renewable ethanol. Its physicochemical features were deeply investigated by a series of characterization technique (XRD, Raman, TPR, SEM and XPS etc). Indeed, the as-prepared composite oxide presented the flower-like morphology structure and exhibited the superior activity and stability even after 50 h on-stream tests for ethanol dry reforming. This attractive behavior was probably assigned to the uniform dispersion of active Cu species and the strong metal-support interaction which could not only efficiently stabilize Cu nanoparticles during the serious reaction conditions but suppress the deactivated coke formation over catalyst surface. The promising findings in this work might stimulate the development of value-added syngas production from renewable biomass-derived feedstocks.

The hole transporting layers (HTLs) between the electrode and light absorber play a vital role in charge extraction and transport processes in organic solar cells (OSCs). Herein, a bilayer structure HTL of CuSCN/TFB is formed by soluble copper(I) thiocyanate (CuSCN) and poly[(9,9-dioctylfluorenyl-2,7-diyl)-alt-(4,4'-(N-(4-butylphenyl)))] (TFB). The excellent charge extraction capability is proved in nonfullerene PM6:Y6 and fullerene PTB7-Th:PC71BM blend system-based cells. The introduction of TFB tunes the work function and polishes the interfacial contact between the HTL and light absorber, which favors the hole extraction process in cells. Meanwhile, lower recombination loss, higher exciton dissociation probability, and larger domain size are observed in CuSCN/TFB HTL-based cells compared to those of the reference cell with the pristine CuSCN HTL, which significantly improve the photovoltaic performance. As a result, a champion efficiency of 15.10% is obtained, which is >14% higher than the efficiency of 13.15% obtained in the reference cell. This study suggests that CuSCN/TFB is a promising HTL to achieve high efficiency for OSCs.

Cold stress restricts peanut (Arachis hypogaea L.) growth, development, and yield. However, the specific mechanism of cold tolerance in peanut remains unknown. Here, the comparative physiological, transcriptomic, and lipidomic analyses of cold tolerant variety NH5 and cold sensitive variety FH18 at different time points of cold stress were conducted to fill this gap. Transcriptomic analysis revealed lipid metabolism including membrane lipid and fatty acid metabolism may be a significant contributor in peanut cold tolerance, and 59 cold-tolerant genes involved in lipid metabolism were identified. Lipidomic data corroborated the importance of membrane lipid remodeling and fatty acid unsaturation. It indicated that photosynthetic damage, resulted from the alteration in fluidity and integrity of photosynthetic membranes under cold stress, were mainly caused by markedly decreased monogalactosyldiacylglycerol (MGDG) levels and could be relieved by increased digalactosyldiacylglycerol (DGDG) and sulfoquinovosyldiacylglycerol (SQDG) levels. The upregulation of phosphatidate phosphatase (PAP1) and phosphatidate cytidylyltransferase (CDS1) inhibited the excessive accumulation of PA, thus may prevent the peroxidation of membrane lipids. In addition, fatty acid elongation and fatty acid β-oxidation were also worth further studied in peanut cold tolerance. Finally, we constructed a metabolic model for the regulatory mechanism of peanut cold tolerance, in which the advanced lipid metabolism system plays a central role. This study lays the foundation for deeply analyzing the molecular mechanism and realizing the genetic improvement of peanut cold tolerance.

In this work, we report a solution processed hole extraction layer (HEL) for highly efficient organic solar cells (OSCs), which is formed by CuSCN and perylene. It shows that the introduction of perylene helps to polish the interface between HEL and active layers, leading to efficient charge transport and collection, diminished recombination loss, and thereby improving the photovoltaic performance. In poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b; 4,5-b′]dithiophene-2,6-diyl-alt-(4-(2-ethylhexyl)-3-fluorothieno[3,4-b]thiophene-)-2-carboxylate-2-6-diyl)]:[6,6]-phenyl C71-butyric acid methyl ester (PTB7-Th:PC71BM) based OSCs, over 9% enhancement of power conversion efficiency (PCE) is obtained in the cells using bilayer CuSCN/perylene as HEL compared with that of the reference cell using pure CuSCN as HEL. The advantage of bilayer CuSCN/perylene HEL is also confirmed in nonfullerene system. An improved PCE is also obtained after application of perylene in nonfullerene system based cell. Furthermore, superior air stability has been observed in CuSCN and CuSCN/perylene HEL based cells. The use of a bilayer CuSCN/perylene HEL proves a potential approach to obtain efficient and stable OSCs.

The olfactory system is responsible for the discrimination and identification of myriad odorant molecules at very low concentrations. On the basis of the gene super family encoding olfactory receptors, it has led to the rapid development of cell based olfactory biosensors. Attempts are currently made not only to imitate the mechanism of the biological nose but also to utilize some of its sensor molecules as functional unities in olfactory biosensors. Recently, the development of olfactory biosensors has achieved rapid advances by using protein molecules and cells, even biological organs as functional elements, that is, odorant binding proteins (OBPs) and olfactory receptors (ORs) at the molecular level, cell based gene engineered cells or olfactory receptor neurons (ORNs), and mammalian olfactory organs. With using the living cells expressing olfactory signal proteins as sensing elements, the cell based biosensors have a naturally evolved selectivity to odorant molecules. Furthermore, the biosensors also ...

Artificial tongue systems are multisensory devices which are highly desirable for the analysis and recognition of complicated composition samples. Herein, a low-cost and simple colorimetric sensor array for identification and quantification of proteins were reported. Using prophyrin, porphyrin derivatives (mainly metalloporphyrins) and chemically responsive dyes as the sensing elements, the developed sensor array of artificial tongue showed a unique pattern of colorific change upon its exposure to proteins. The composite pattern for each sample was subjected to principal component analysis (PCA), thus providing a clustering map for more practical visualization. All the pure and mixed proteins, as well as denatured proteins, gave distinct patterns, thus resulting in their unambiguous identification. The PCA analysis also suggested that the unique pattern of colorific change may be due to the change of protein conformation and local environmental pH. These results demonstrate that the developed colorimetric artificial tongue system is an excellent sensing platform for identification and quantitative analysis of protein samples.

Recent advances in optical detection methods and techniques applied in cell-based microfluidic systems are reviewed, and these methods mainly focused on microsystems that integrate on-chip cell culture, real-time detection, and recent advances in correlated detection methods and techniques. The comparison of six optical detection methods and techniques are summarized, and their research applicability for cell study is proposed. The trend and the development perspective of each technique applied for label-free, real-time detection and sensing of living cell are discussed. Finally, an assessment of future directions for lab chip-based cell research and sensing microsystem is concluded.

The development of colorimetric sensor array for the detection of natural amino acids is reported. Using a cross-responsive array containing a diverse family of chemically responsive dyes, the colorimetric sensor array provides enormous discriminatory power among different analytes. Digital imaging of the dye array before and after immersion provides a color change profile as a unique fingerprint for each specific analyte. The 6×6 array used in this research has 36 dyes that were sensitive to amino acids. A functional portable type apparatus was developed for data acquisition and data processing. Using colorimetric sensor arrays, 10 natural amino acids have been analyzed within 5 min of exposure at concentrations of 375 μM. The digital data library generated was analyzed with statistical and chemometric methods, including principal component analysis (PCA) and linear discriminant analysis (LDA). Facile identification of all the amino acids was readily achieved using comparison of the color change profiles or a PCA score plot. Using LDA analysis, the classification accuracy of identification was 97%. These results suggest that colorimetric sensor arrays may prove to be useful for the identification of natural amino acids, and they also represent a potential application in the field of cell recognition, food quality assurance, and microbial identification.

Tungsten trioxide is an n-type semiconductor, which has been extensively used for the development of metal oxide semiconductor gas sensors. The hydrogen gas sensing performance of platinum (Pt) catalyst activated WO3 thin films were investigated here. All of the Pt/WO3 films membranes are sensitive to hydrogen gas and the sample by sol-gel and DC reactive magnetron sputtering methods. X-ray diffraction results indicate that the tungsten trioxide is cubic crystal, and the AFM analysis shows molecular structures of the samples are tetrahedron. It means the four consecutive quadrilateral forms we observed in the 9nmx9nm molecular structure are scattergram of tungsten-ions and oxide-ions on 106 sides in WO2.9 structure cell, and the lost one oxide-ion resulted in the transition of WO3 to WO2.9 . With anneal temperature rising, the membranous poriness decreasing. The higher crystal degree is, the lower gasochromic efficiency is. The change of combining environment and content of O−2 ions in colorized / decolorized state WOx films was observed in XPS analysis of Pt/WO3 film, the peak shape had changed greatly. As a result, the explanation to this phenomenon is available here according to XPS chemical shift of electric potential model theory.Copyright © 2008 by ASME