Effect of Nano TiO2 on Self-cleaning Property of Cross-linking Cotton Fabric with Succinic Acid Under UV Irradiation

Optimization of curing cotton textiles through self-cleaning property constructs the main goal of the present study. Cotton fabrics with 0.1, 0.3, 0.5, 1 and 1.5 on weight of bath percent were cured by nano titanium dioxide (P25 Degussa) with cross-link and non cross-link methods. In this study, succinic acid was used as a cross-link agent to attach TiO₂ to the cotton. The amount of loaded titania particles to cotton fabrics and the thermal behavior of cured samples were studied by the burning method and thermogravimetric analysis, respectively. Self-cleaning degree of cured samples, stained with natural and synthesized dyes under irradiation of 20 and 400 W UV lamps was investigated by a reflectance spectrophotometer. The structure and morphology of treated cotton fabrics were investigated using scanning electron microscopy and crystallinity of titania coatings by X-ray diffraction spectroscopy. The tearing strengths of titania-coated cotton fabrics before and after light irradiation were measured. Results showed that the stability of nano TiO₂ coating and self-cleaning degree of treated samples with cross-link method were much higher than those of non cross-link method, and cotton cellulosic chains were not decomposed by the photocatalytic activity of titania.     

Construction of stable multivariate calibration models using unsupervised segmented principal component regression

In multivariate spectral calibration by principal component regression (PCR), the principal components (PCs) are calculated from the response data measured at all employed instrument channels; however some channels are redundant and their responses do not possess useful information. Thus, the extracted PCs possess mixed information from both useful and redundant channels. In this work, we propose a segmentation approach based on unsupervised pattern recognition to identify the most informative spectral region and then to construct a stable multivariate calibration model by PCR. In this method, the instrument channels are clustered into different segments via Kohonen self‐organization map. The spectral data of each segment are then subjected to PCA and the derived PCs are used as input variables for an inverse least square (ILS) regression model employing stepwise selection of the informative PCs. The proposed method was evaluated by the analysis of four simulated and six experimental data sets. It was found that our proposed method can model the above data sets with prediction errors lower than conventional partial least squares (PLS) and PCR methods. In addition, the prediction ability of our method was better than the previously reported models for these data sets. Copyright © 2011 John Wiley & Sons, Ltd.     

A Comprehensive Review of Lithium-Ion Capacitor Technology: Theory,Development, Modeling,Thermal Management Systems,and Applications

This review paper aims to provide the background and literature review of a hybrid energy storage system (ESS) called a lithium-ion capacitor (LiC). Since the LiC structure is formed based on the anode of lithium-ion batteries (LiB) and cathode of electric double-layer capacitors (EDLCs), a short overview of LiBs and EDLCs is presented following the motivation of hybrid ESSs. Then, the used materials in LiC technology are elaborated. Later, a discussion regarding the current knowledge and recent development related to electro-thermal and lifetime modeling for the LiCs is given. As the performance and lifetime of LiCs highly depends on the operating temperature, heat transfer modeling and heat generation mechanisms of the LiC technology have been introduced, and the published papers considering the thermal management of LiCs have been listed and discussed. In the last section, the applications of LiCs have been elaborated.     

Live-cell imaging reveals impaired detoxification of lipid-derived electrophiles is a hallmark of ferroptosis

The central mechanism in ferroptosis linking lipid hydroperoxide accumulation with cell death remains poorly understood. Although lipid hydroperoxides are known to break down to reactive lipid-derived electrophiles (LDEs), the ability of cells to detoxify increasing LDE levels during ferroptosis has not been studied. Here, we developed an assay (ElectrophileQ) correlating the cellular retention vs. excretion of a fluorogenic lipophilic electrophile (AcroB) that enables live-cell assessment of the glutathione-mediated LDE conjugation and adduct export steps of the LDE detoxification pathway. This method revealed that during ferroptosis, LDE detoxification failure occurs through decreased conjugation or export impairment, amplifying cellular electrophile accumulation. Notably, ferroptosis susceptibility was increased following exacerbation of LDE-adduct export impairment through export channel inhibition. Our results expand understanding of the ferroptosis molecular cell death mechanism to position the LDE detoxification pathway as a ferroptosis-relevant therapeutic target. We envision the ElectrophileQ assay becoming an invaluable tool for studying ferroptosis and cellular health.

A link between altered lipid-derived electrophile (LDE) metabolism during ferroptosis and associated cell death was uncovered using a new imaging method developed to monitor cellular LDE detoxification that employs a fluorogenic LDE analogue.     

Vinyl Halide-Modified Unsaturated Cyclitols are Mechanism-Based Glycosidase Inhibitors

Suitably configured allyl ethers of unsaturated cyclitols act as substrates of β-glycosidases, reacting via allylic cation transition states. Incorporation of halogens at the vinylic position of these carbasugars, along with an activated leaving group, generates potent inactivators of β-glycosidases. Enzymatic turnover of these halogenated cyclitols (F, Cl, Br) displayed a counter-intuitive trend wherein the most electronegative substituents yielded the most labile pseudo-glycosidic linkages. Structures of complexes with the Sulfolobus β-glucosidase revealed similar enzyme-ligand interactions to those seen in complexes with a 2-fluorosugar inhibitor, the lone exception being displacement of tyrosine 322 from the active site by the halogen. Mutation of Y322 to Y322F largely abolished glycosidase activity, consistent with lost interactions at O5, but minimally affected (7-fold) rates of carbasugar hydrolysis, yielding a more selective enzyme for unsaturated cyclitol ether hydrolysis.