Fouling behavior of nanofiltration membrane during the refining treatment of morphlines-dominant reverse osmosis concentrate.

Nanofiltration (NF) has been proven to be with great potential for the separation of morpholines with molecular weight less than 200 Da in refining reverse osmosis concentrate (ROC), but its application is significantly restricted by the membrane fouling, which can reduce the rejection and service time. To enable the long-term operation stability of nanofiltration, this work focuses on the fouling behavior of each substance in the hydrosaline organic solution on nanofiltration membrane, aiming to give insight into the fouling mechanism. To this end, in this work, the effects of salts (i.e NaCl and Na2SO4), organic substances (including N-(2-hydroxypropyl)morpholine(NMH) and 4-morpholineacetate(MHA)) and representative divalent ions (Ca2+ and Mg2+) on the performance and physicochemical properties of DK membrane were systematically investigated. The results show that both salts and organics can induce DK membrane swelling, leading to an increase of the mean effective pore size. After the filtration of Na2SO4-NaCl-H2O, the mean pore size increased by 0.002 nm, resulting in the decrease of the removal ratio of NMH and MHA for 3.82% and 13.10%, respectively. With static adsorption of NMH and MHA, the mean pore size of DK membrane increased by 0.005 and 0.003 nm. The swelling slowed the entrance of more organic molecules into membrane pores. Among them, MHA led to the terrible irreversible pore blocking. As the concentration of Ca2+ increased, gypsum scaling was formed on the membrane surface. During this process, NMH and MHA played different roles, i.e. NMH accelerated the CaSO4 crystallization while MHA inhibited. As a conclusion, the fouling behavior of substances in the high saline organic wastewater on DK membrane were systematically revealed with the fouling mechanisms proposed, which could provide an insightful guidance for membrane fouling control and cleaning in the treatment of high salinity and organic wastewater.

Microwave-assisted DES fabrication of lignin-containing cellulose nanofibrils and its derived composite conductive hydrogel.

Deep eutectic solvents (DES) have been regarded as green solvents in the biorefinery of lignocellulosic biomass, but long duration time has severely limited efficiency. The microwave-assisted DES pretreatment along with enzymatic hydrolysis and high-pressure homogenization process was proposed to produce lignin-containing cellulose nanofibrils (LCNF) from corncob. Benefiting from microwave-assisted DES pretreatment, the duration time was greatly shortened; meanwhile the effects of different kinds of DES on the resultant LCNF were investigated. The results showed that, the microwave-assisted DES fabricated LCNF (M-LCNF) was successfully obtained, exhibiting good nano size, thermal stability, colloidal stability, and fluorescence. M-LCNF was further introduced into phytic acid (PA) enhanced poly(acrylamide-co-acrylic acid) (P(AM-co-AA)) network and constructed composite conductive hydrogels (PLP). The obtained hydrogels exhibited good mechanical strength, UV blocking ability, fluorescence, and conductivity. A simple battery assembled with the resultant PLP as electrolyte had an out voltage of 2.41 V. The composite conductive hydrogel showed good sensing performance towards different stimuli (e.g., stretching and compression) and human motions in real time. It is expected that this research would provide an alternative way for green fabrication of LCNF and potential application of LCNF in flexible sensors.

Triptolide promotes ferroptosis by suppressing Nrf2 to overcome leukemia cell resistance to doxorubicin.

Doxorubicin (DOX) is an extensively used chemotherapeutic drug to treat leukemia. However, there remains a pivotal clinical problem of resistance to DOX in patients with leukemia. Erythroid 2­related factor 2 (Nrf2) is a master regulator of antioxidation response which serves a critical role in maintaining cellular oxidative homeostasis. However, whether Nrf2 is involved in DOX resistance is not totally clear. It is well­documented that triptolide, a widely used drug to treat autoimmune disorders, possesses anti­cancer activities, yet whether triptolide affects leukemia cell sensitivity to DOX remains to be elucidated. The present study aimed to determine the role of triptolide­mediated downregulation of Nrf2 in regulating leukemia cell ferroptosis and resistance to DOX. For this purpose, low­dose DOX was used to establish DOX­resistant K562 cells and HL­60 cells. Nrf2 mRNA and protein expression were examined by quantitative PCR and western blotting assays. The effects of triptolide on leukemia cell viability, reactive oxygen species (ROS) levels, or lipid oxidation were determined by CCK8 assay, DCFH­DA assay, or BODIPY 581/591 C11 assay, respectively. The results show that Nrf2 expression was significantly upregulated in DOX­resistant leukemia cells and clinical leukemia samples. Silencing of Nrf2 significantly sensitized leukemia cells to DOX. Furthermore, it was demonstrated that triptolide inhibited Nrf2 expression and induced leukemia cell ferroptosis, as evidenced by increased ROS levels and lipid oxidation as well as decreased glutathione peroxidase 4 expression. Ectopic expression of Nrf2 significantly rescued triptolide­induced leukemia cell ferroptosis. Notably, the present study showed that triptolide re­sensitized DOX­resistant leukemia cells to DOX. In conclusion, the present study indicated that Nrf2 served a critical role in leukemia cell resistance to DOX and triptolide­induced ferroptosis and suggested a potential strategy of combination therapy using triptolide and DOX in leukemia treatment.

Prussian blue analogs-based layered double hydroxides for highly efficient Cs+ removal from wastewater.

In this work, novel Prussian blue analogs-based layered double hydroxide (PBA@ZnTi-LDH) was in situ synthesized and used for radioactive Cs+ removal from wastewater. The results suggested that this PBA@ZnTi-LDH prepared using LDH as skeleton and transition metal source showed higher adsorption capacity (243.9 mg/g) and water stability than conventional PBAs, and promising application in scale-up Cs+ removal. Thus, it was granulated by calcium alginate and the PBA@ZnTi-LDH/CaALG exhibited favorable post-separation and fixed-bed adsorption ability at different Cs+ concentrations and flow rates, highlighting its application perspective on Cs+ removal from various kinds of wastewater. Moreover, the real-world Cs+ removal was preliminarily explored using natural complex Cs+-containing water. As a result, this stable and easily separated PBA@ZnTi-LDH/CaALG showed high removal efficiency, selectivity and good reusability, which was promising in scale-up Cs+ removal from the real-world wastewater.

Enhanced kinetics and super selectivity toward Cs+ in multicomponent aqueous solutions: A robust Prussian blue analogue/polyvinyl chloride composite membrane.

Developing effective adsorbents for 137Cs removal from complex wastewater systems has been a significant challenge. Although existing spheres adsorbents could improve the post-separation ability and practical operability, the adsorption kinetics are still significantly retarded due to the large intra-particle diffusion resistance. Here, we demonstrate the efficiency of a robust Prussian blue analogue/polyvinyl chloride composite membrane (PPM), which was easily prepared by a simple solvent evaporation method. In virtue of the less dense layer and ion-sieving functionality, it showed enhanced kinetics (5 h) and super selectivity (SF = 248.3-5388.6) towards Cs+. New PPM was robust within a wide pH range (2-10) and exhibited favorable removal capacity (152.8 mg/g), placing it at an outstanding material for Cs+ removal among other adsorbents. Moreover, PPM could be simply eluted and reused using a KCl solution as eluent. A study of the adsorption mechanism confirmed an ion-exchange action during the removal process. Thus, PPM is considered to be a promising candidate for the removal of Cs+ from multicomponent aqueous solutions.

The Small Molecule P7C3-A20 Exerts Neuroprotective Effects in a Hypoxic-ischemic Encephalopathy Model via Activation of PI3K/AKT/GSK3ß Signaling.

Hypoxic-ischemic encephalopathy (HIE) in neonates can lead to severe long-term disabilities including cerebral palsy and brain injury. The small molecule P7C3-A20 has been shown to exert neuroprotective effects in various disorders such as ischemic stroke and neurodegenerative diseases. However, it is unclear whether P7C3-A20 has therapeutic potential for the treatment of HIE, and the relationship between P7C3-A20 and neuronal apoptosis is unknown. To address these questions, the present study investigated whether P7C3-A20 reduces HI injury in vitro using a PC12 cell oxygen-glucose deprivation (OGD) model and in vivo in postnatal day 7 and 14 rats subjected to HI, along with the underlying mechanisms. We found that treatment with P7C3-A20 (40-100 µM) alleviated OGD-induced apoptosis in PC12 cells. In HI model rats, treatment with 5 or 10 mg/kg P7C3-A20 reduced infarct volume; reversed cell loss in the cortex and hippocampus and improved motor function without causing neurotoxicity. The neuroprotective effects were abrogated by treatment with the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002. These results demonstrate that P7C3-A20 exerts neuroprotection by activating PI3K/protein kinase B/glycogen synthase kinase 3ß signaling and can potentially be used to prevent brain injury in neonates following HIE.

Facile Synthesis of Porous Polymer Using Biomass Polyphenol Source for Highly Efficient Separation of Cs+ from Aqueous Solution.

In this work, a series of polyphenol porous polymers were derived from biomass polyphenols via a facile azo-coupling method. The structure and morphologies of the polymer were characterized by BET, TEM, SEM, XRD, TGA and FT-IR techniques. Batch experiments demonstrated their potentialities for adsorptive separation of Cs+ from aqueous solution. Among them, porous polymers prepared with gallic acid as starting material (GAPP) could adsorb Cs+ at wide pH value range effectively, and the optimal adsorption capacity was up to 163.6 mg/g, placing it at top material for Cs+ adsorption. GAPP exhibited significantly high adsorption performance toward Cs+ compared to Na+ and K+, making it possible in selective removal of Cs+ from ground water in presence of co-existing competitive ions. Moreover, the Cs-laden GAPP could be facilely eluted and reused in consecutive adsorption-desorption processes. As a result, we hope this work could provide ideas about the potential utilization of biomass polyphenol in environmental remediation.

Robust and recyclable sodium carboxymethyl cellulose-ammonium phosphomolybdate composites for cesium removal from wastewater.

A novel, facilely prepared, recyclable sodium carboxymethyl cellulose-ammonium phosphomolybdate composite (CMC-AMP) was synthesized by chemical cross-linking and used for Cs+ removal. The effects of adsorbent dosage, pH value, initial Cs+ concentration, contact time, temperature and competitive ions on adsorption were investigated. The results showed that CMC-AMP with good mechanical properties could effectively adsorb Cs+ in a wide pH range. In addition, the adsorption process of CMC-AMP was better fitted with the Lagergren first-second model and Langmuir isotherm model. Furthermore, CMC-AMP can be reused five times using ammonium chloride as the eluent without an obvious decrease in absorption activity. The results reveal that CMC-AMP can be used as a low cost and recyclable Cs+ adsorbent.

Composite hydrogel particles encapsulated ammonium molybdophosphate for efficiently cesium selective removal and enrichment from wastewater.

A novel ammonium molybdophosphate (AMP)/ polyvinyl alcohol (PVA)/ sodium alginate (SA) composite hydrogel (APS) was prepared for Cs+ removal and enrichment from radioactive wastewater. Batch experiments with the subject of AMP concentration, pH value, initial Cs+ concentration, contact time, temperature, competing ions were investigated. The results showed this APS hydrogel with high permeability and stability could effectively adsorb Cs+ at widely broad pH value range and low Cs+ concentration within a short time. Adsorption thermodynamic parameters indicated the endothermic and spontaneous nature of the adsorption process, and the Lagergren pseudo-second order model was found to exhibit the best correlation with the adsorption results. Equilibrium data was better described by the Langmuir isotherm equation, and the maximum adsorption capacity of APS hydrogel calculated was in consistent with the experimental results. Furthermore, the APS hydrogel could be easily reused at least five times without obvious decrease in absorption activity and selectivity using ammonia nitrate as the eluent, and what's more, the Cs+ concentration in eluent was approximately concentrated for 2 times after single cycle. All the results suggest that the environmental friendly and low-cost APS hydrogel could be used as effective and selective material for Cs+ removal and enrichment from wastewater.

Basic Salt-Lake Brine: An Efficient Catalyst for the Transformation of CO2 into Quinazoline-2,4(1 H,3 H)-diones.

The efficient transformation of CO2 into value-added chemicals with green, abundant, and cheap catalysts is an interesting and challenging topic in both green and sustainable chemistry. In this study, a series of salt-lake brines were used for the first time to catalyze the reaction of CO2 and a broad range of 2-aminobenzonitriles to form the corresponding quinazoline-2,4(1 H,3 H)-diones. It was found that the abundant, available, and inexpensive Zhabuye basic salt-lake brine could efficiently promote the reaction of 2-aminobenzonitriles under low pressure of CO2 . Very high yields of value-added products were obtained. Further studies indicated that the basic carbonate and borate ions in the brine play key roles in accelerating the reactions.