Cellulose-citric acid-chitosan@metal sulfide nanocomposites: Methyl orange dye removal and antibacterial activity.

In this study, to develop efficient adsorbents in removing water pollution, new cellulose-citric acid-chitosan@metal sulfide nanocomposites (CL-CA-CS@NiS and CL-CA-CS@CuS) were synthesized by one-pot reaction at mild conditions and characterized using X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscope (SEM), Energy Dispersive X-ray (EDX) and Brunauer-Emmett-Teller (BET) isotherm. The results of characterization techniques confirm that the desired compounds have been successfully synthesized. The as-prepared composites were applied for the removal of methyl orange (MO) dye from aqueous solutions using a batch technique, and the effect of key factors such as initial pH, shaking time, MO concentration, temperature and adsorbent dose were investigated and discussed. Adsorption results exhibited positive impact of temperature, shaking time and adsorbent dose on the MO removal percent. The MO removal percent has been increased over a wide range of pH from 2 (27.6 %) to 6 (98.8 %). Also, almost being constant over a wide range of MO concentration (10-70 mg/L). The results demonstrated that the maximum removal percentage of MO dye (98.9 % and 93.4 % using CL-CA-CS@NiS and CL-CA-CS@CuS, respectively) was achieved under the conditions of pH 6, shaking time of 120 min, adsorbent dose of 0.02 g, MO concentration of 70 mg/L and temperature of 35 °C. The pseudo-second-order (PSO) and Langmuir models demonstrated the best fit to the kinetic and equilibrium data. Also, the thermodynamic results showed that the MO removal process is endothermic and spontaneous in nature. The MO adsorption can be happened by different electrostatic attraction, n-π and π-π stacking and also hydrogen bonding interaction. In addition, antibacterial activity of CL-CA-CS@NiS and CL-CA-CS@CuS nanocomposites exhibited a superior efficiency against S. aureus.

Chemically tailored molecular surface modification of bamboo pulp fibers for manipulating the electret performance of electret filter media.

The surface chemical composition of materials is essential for regulating their charge trapping and storage capabilities, which directly affect their electret performance. Although chemical modification of materials to alter electret performance has been investigated, the mechanism through which electret properties are regulated more systematically via chemical customization has not been elucidated in detail. Herein, p-phenylenediamine, benzidine and 4,4'-diaminotriphenyl, which have different conjugated strength functional groups, were selected to chemically tailor the surface of bamboo pulp fibers to regulate the electret properties and elucidate the regulatory mechanism more systematically. The results showed that the charge trapping and storage properties of materials could be regulated by introducing functional groups with different conjugated strengths to their surfaces, realizing the regulation of the electret properties. Moreover, the charge trapping and storage ability could be tailored more specifically by regulating the number of functional groups. By chemical customization to provide electrostatic effects to the materials, the purification time was reduced by approximately 45 %-52 %. More importantly, a relatively systematic mechanism was proposed to elucidate the effect of the conjugate group strength on the charge trapping and charge storage properties of the material. These findings will provide guidance for the investigation of chemical modifications to regulate the electret performance of materials.

Rheological and radioactive decontamination properties of ethyl cellulose sols in green solvents at a temperature below 0 °C.

Strippable film decontamination has been considered one of the best prospects for radioactive surface decontamination due to its high decontamination effect and less secondary pollution. However, research into strippable films has until now focused on radioactive decontamination at room temperature. Therefore, it is vital to seek a suitable degradable material for preparing strippable films in removing contaminants in an extremely cold region, as it will face the problem of the freezing of the detergent. Ethyl cellulose (EC) is a kind of degradable biopolymer which is easily dissolved in volatile green organic solvents to form a sol below 0 °C which is advantageous for forming a film. Therefore, it would be the best choice for preparing a strippable film detergent. In this study, EC sols were obtained by placing EC powder into the green solvents anhydrous ethanol and ethyl acetate. The steady and dynamic rheological behavior of EC sols was investigated with a rotary rheometer with the temperature ranging from -10 °C to 0 °C to disclose their spraying performance. Moreover, the radioactive decontamination effect of EC sols and the mechanism were also investigated. The results showed that the EC sols were pseudoplastic fluids which obeyed the Ostwald-de Waele power law below 0 °C. Furthermore, the viscosity of EC sols could be reduced by stirring, which is convenient for large-area spraying during decontamination below 0 °C. At -10 °C, the comprehensive decontamination rates of all plates were over 85%. Therefore, EC sols could be used as a basic material for strippable film decontamination below 0 °C.

Laxative effect of Wenyang Yiqi Decoction on loperamide-induced astriction model mice.

Background: Although a common disease, astriction is difficult to treat and severely affects quality of life. Wenyang Yiqi Decoction (WYD) is a kind of traditional Chinese medicine (TCM) that is used to treat astriction; however, the mechanism remains unclear. Therefore, this work assessed the laxative effect of WYD on loperamide-induced astriction (LIA) model mice. Methods: We replicated a constipation model in mice and detected changes in fecal parameters such as feces quantity and water content, intestinal transit function, and histopathological changes in the constipated mice. After five days of WYD intervention, mouse tissues were taken out for detection. We also measured the levels of gastrin (Gas), substance P (SP), acetylcholinesterase (AChE), and vasoactive intestinal peptide (VIP) in the mice's serum. Additionally, we used quantitative real-time polymerase chain reaction (qRT-PCR) and Western Blot to detect c-Kit and stem cell factor (SCF), and examined the effects of WYD on the tight junction (TJ) proteins occludin (Ocln), zonula occludens-1 (ZO-1), and claudin-1 (Cldn-1) in the mice's intestines. Results: Through histopathological changes, we observed less destruction of epithelial cells and greater integrity of goblet and epithelial cells in WYD-treated mice than in mice in the loperamide group. qRT-PCR and western blot analysis of c-Kit and SCF showed that WYD could boost the levels of c-Kit and SCF. The qRT-PCR and immunohistochemical (IHC) analyses of enteral tight occludin (Ocln), occludenas-1 (ZO-1), and cldin-1 (Cldn-1) showed that WYD could boost the level of ZO-1 and decrease the level of Cldn-1. The study also investigated the effect of WYD treatment on the enteral barrier function of astriction model mice and found that the TJ proteins (ZO-1, Cldn-1) in the colon of the astriction model mice had significant changes compared to the normal group, and WYD intervention was found to increase the expression of ZO-1, and decrease the expression of Cldn-1. Conclusions: WYD alleviates LIA by regulating enteral hormones, boosting the number of interstitial cells of Cajal (ICCs), or adjusting enteral block action.

Ameliorative effect of sevoflurane on endoplasmic reticulum stress mediates cardioprotection against ischemia-reperfusion injury 1.

We aimed to investigate whether the cardioprotection of sevoflurane against ischemia-reperfusion (IR) injury is via inhibiting endoplasmic reticulum stress. The rat in vivo model of myocardial IR injury was induced by ligation of the left anterior descending coronary artery. Sevoflurane significantly ameliorated the reduced cardiac function, increased infarct size, and elevated troponin I level and lactate dehydrogenase activity in plasma induced by IR injury. Sevoflurane suppressed the IR-induced myocardial apoptosis. The increased protein levels of glucose-regulated protein 78 and C/EBP homologous protein (CHOP) after myocardial IR were significantly reduced by sevoflurane. The protein levels of phosphorylated protein kinase RNA-like endoplasmic reticulum kinase (PERK), phosphorylated eukaryotic initiation factor 2 (eIF2α), and activating transcription factor 4 (ATF4) were significantly increased in rats with IR and attenuated by sevoflurane treatment. The phosphorylation of Akt was further activated by sevoflurane. The cardioprotection of sevoflurane could be blocked by wortmannin, a PI3K/Akt inhibitor. Our results suggest that the cardioprotection of sevoflurane against IR injury might be mediated by suppressing PERK/eIF2a/ATF4/CHOP signaling via activating the Akt pathway, which helps in understanding the novel mechanism of the cardioprotection of sevoflurane.