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In this work, underground brine (UGB) with high salinity was concentrated using a thin-film composite (TFC) hollow fiber forward osmosis (FO) membrane. The TFC hollow fiber FO membrane has an active polyamide separation layer at the inner surface; the membrane showed a water permeability coefficient of 1.8 L m−2 h−1 bar−1, a salt rejection of 93%, a structural parameter of 335 μm and a water flux of 15.1 L m−2 h−1 (active layer facing feed solution, AL-FS). Using saturated NaCl solution as the draw solution at the shell side, the increase of the flow rate of the UGB at the hollow fiber from 10 mL min−1 to 280 mL min−1 resulted in an increase in the flux from 0.8 L m−2 h−1 to 12.2 L m−2 h−1. Osmotic backwashing and chemical cleaning were adopted to mitigate membrane scaling and their effects were evaluated. Chemical cleaning using Na2EDTA was found to be more efficient in mitigating membrane scaling than osmotic backwashing, but at the expense of negative influence on the active surface separation performance.

Chinese salt-lake brine is mainly of the magnesium sulfate subtype with a high Mg/Li ratio. Mining lithium from Chinese salt-lake brine has been a decades-long technical challenge. The pros and cons of various technologies are briefly discussed. Chemical extraction has been the most important technology for the recovery of lithium from Chinese salt-lake brine with a high Mg/Li ratio. Several other innovative technologies, including lithium ion sieves, membrane separation, and electro–electrodialysis, have also emerged as potential options.

Multifunctional high-performance La1−xSrxMnO3@Au core–shell nanoparticles were successfully synthesized by a modified nanoemulsion method with the assistance of poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (PEO-PPO-PEO). X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses confirm the structure and morphology of the nanoparticles. The measurements obtained using ultraviolet-visible light absorbance spectrometry (UV-vis), vibrating sample magnetometry (VSM), and a physical property measurement system (PPMS) demonstrate that the nanoparticles exhibit a surface plasmon resonance (SPR) absorption band around 561 nm from nanostructured Au and a unique magnetic nature at room temperature. Particularly, a sharp, tight phase transition from ferromagnetic to superparamagnetic states is observed in a free-standing La1−xSrxMnO3 nanoparticle system for the first time with a Curie temperature around room temperature. The cytotoxicity of the nanoparticles was studied for safe biomedical applications using an MTT assay. The results show that the La1−xSrxMnO3@Au core–shell nanoparticles with lower cytotoxicity, well-defined magnetic and optical properties are promising for optical, magnetic, and biomedical application.

Considering the complex etiology of Alzheimer’s disease (AD), multifunctional agents may exhibit important properties against this disease. A series of 6-substituted 3-arylcoumarins (5a–t) were designed, synthesized and evaluated as cholinesterase (ChE) and monoamino oxidase (MAO) inhibitors. Among them, compounds 5o [IC50, 195 nM for human acetylcholinesterase (hAChE), selectivity index, SI (human butyrylcholinesterase, hBuChE/hAChE) = 145; IC50, 63.5 nM for human monoamine oxidase-B (hMAO-B), SI (human monoamine oxidase-A, hMAO-A/hMAO-B) = 25] and 5p [IC50, 185 nM for hAChE, SI (hBuChE/hAChE) = 182; IC50, 196 nM for hMAO-B, SI (hMAO-A/hMAO-B) > 510] were found to selectively inhibit both hAChE and hMAO-B with IC50 values in the nanomolar range. The abilities of 5o and 5p to bind to hAChE and hMAO-B were confirmed by molecular docking and kinetic studies. Moreover, 5o and 5p were found to exhibit significant inhibition of self-induced Aβ42 aggregation (61% and 52%, at 20 μM), have antioxidant properties (0.81 and 1.17 trolox equivalent by ABTS assay), provide neuroprotection against Aβ42-induced cytotoxicity and blood–brain barrier (BBB) penetration capacity (PAMPA-BBB+), and are thus potential anti-Alzheimer agents with balanced activities. Overall, the study provided meaningful information for further development of multifunctional drugs for AD therapy.

A series of 3-Schiff base-4-hydroxycoumarin derivatives (1–20) have been designed, synthesized and evaluated as multifunctional agents against Alzheimer's disease. In vitro studies indicated that most of the derivatives exhibited significant abilities to inhibit monoamine oxidase (MAO), self-induced and Cu2+-induced β-amyloid (Aβ1–42) aggregati006Fn, as well acting as potential biometal chelators and antioxidants. Moreover, these derivatives were capable of decreasing reactive oxygen species (ROS) and showed good neuroprotective effects in PC12 cells and could penetrate the central nervous system (CNS). In particular, compound 4 exhibited high potency to monoamine oxidase (IC50, 0.673 μM for hMAO-A, 0.711 μM for hMAO-B), good antioxidant activity (1.34 trolox equivalents by ABTS method, 45.8 μM of IC50 by DPPH method), and it also displayed a significant ability to inhibit self-induced and Cu2+-induced Aβ1–42 aggregation (60.1%, 20 μM and 45.7%, 50 μM). Taken together, these results suggested that compound 4 might be a promising lead compound with balanced properties for AD treatment.

Two series of acetophenone derivatives have been designed, synthesized and evaluated for human monoamine oxidase A and B inhibitory activity in vitro. Most of the tested compounds acted preferentially on MAO-B with IC50 values in the nanomolar range and weak or no inhibition of MAO-A. In particular, compounds 1j (IC50 = 12.9 nM) and 2e (IC50 = 11.7 nM) were the most potent MAO-B inhibitors being 2.76- and 2.99-fold more active than selegiline. In addition, the structure–activity relationships for MAO-B inhibition indicated that substituents at C3 and C4 of the acetophenone moiety, particularly with the halogen substituted benzyloxy, were more favorable for MAO-B inhibition. Molecular docking and kinetic studies have been carried out to explain the binding modes of MAO-B with the acetophenone derivatives. Furthermore, the representative compounds 1j and 2e showed low neurotoxicity in SH-SY5Y cells. It may be concluded that the acetophenone derivatives could be used to develop promising lead compounds for treating neurodegenerative diseases.

A new composite hollow fiber nanofiltration (NF) membrane with a thin sulfonated poly(ether ether ketone) (SPEEK) active layer was prepared and used for arsenic removal. The effects of the feed concentration, pH and transmembrane pressure on arsenic removal were systematically examined. The obtained SPEEK hollow fiber NF membrane could achieve an As(V) rejection of over 95% and water permeability of 11 L m−2 h−1 bar−1. These excellent As(V) rejection and high water permeability were attributed to the highly negatively charged surface of the SPEEK membrane, which could enhance the As(V) rejection through the Donnan exclusion mechanism or electrostatic repulsion between the negatively charged arsenate species and the negatively charged SPEEK membrane surface. A preliminary techno-economic assessment of a 1000 m3 h−1 plant suggests that using the proposed SPEEK hollow fiber membrane, the treatment cost was 0.15 US$ per m3, which thus could be economically viable for arsenic removal applications in China.

The polymer-coated AgZnO nanoparticles were synthesized via a one-pot process with the assistance of the triblock copolymer, poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (PEO-PPO-PEO). The nanoparticles were characterized by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) including the mode of high resolution (HRTEM) and by energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible light absorbance spectrometry (UV-vis) and photoluminescence spectrophotometry (PL). It is found that the nanoparticles reveal high crystallinity, good dispersibility, and excellent optical performance both in organic and aqueous solvents. The photocatalytic behavior of the AgZnO nanoparticles was scrutinized using rhodamine B (RhB) as probe molecule. The results show that the degradation efficiency of the AgZnO nanoparticles is higher than that of the ZnO nanoparticles under both UV and sunlight irradiation, 89.5% and 66.9% for the former and 52.7% and 37.5% for the latter after 90 minute exposure, respectively. Moreover, the AgZnO nanoparticles were found to have the photocatalytic efficiency unaltered after 5 cycles of use as tested. Our results demonstrate that the nanostructured AgZnO nanoparticles exhibit enhanced photocatalytic performance and high stability. Consequently, the AgZnO nanoparticles are favorable candidates for potential application as a promising photocatalyst.

The sluggish oxygen reduction kinetics and insufficient durability of cathode catalysts restrict the practical application of proton exchange membrane fuel cells. This study focuses on the structural transformation of carbon-supported Pt3Cr from a disordered to an ordered phase and on the effect of such structural transformation on oxygen reduction reaction (ORR) activity and durability. X-ray diffraction and transmission electron microscopy results confirm the formation of carbon-supported Pt3Cr intermetallic nanoparticles with a mean particle size of ca. 7.2 nm. Line scanning EDX reveals that the practical Pt–Cr atomic ratio is approximately 3 : 1. X-ray photoelectron spectroscopy results indicate that the proportion of metallic Pt increases while the binding energy of Pt 4f decreases with such structural transformation. The Pt3Cr/C intermetallic nanoparticles exhibit enhanced mass and specific activities toward the ORR compared with commercial Pt/C but slightly lower mass activity than the disordered Pt3Cr/C alloy nanoparticles. After the accelerated durability test for 5000 cycles, the Pt3Cr intermetallic nanoparticles displayed negligible decay in ORR mass activity; however the ORR mass activity on the isordered Pt3Cr alloy decreases to ca. 50%. Much enhanced durability of the Pt3Cr/C intermetallic nanoparticles toward the ORR is definitely caused by the much higher structural and compositional stabilities of the Pt3Cr/C intermetallic nanoparticles than that of the disordered Pt3Cr/C alloy nanoparticles, suggesting that the Pt3Cr intermetallic nanoparticles may serve as highly active and durable ORR electrocatalysts for practical application.

Mn–Ru binary oxides have been synthesized via a hydrothermal approach and their performance as bifunctional catalysts for the air electrode is evaluated in non-aqueous Li–O2 secondary batteries. Characterization of the catalysts by X-ray diffractometry and transmission electron microscopy confirms that the as-prepared oxides contain γ-MnO2 and hydrous RuO2 with the morphology of fusiform nanorods and nanoparticles, respectively. Linear scanning voltammetric measurements reveal that the binary oxides exhibit remarkable electrocatalytic activities towards both the oxygen reduction and oxygen evolution reactions. Li–O2 batteries with Mn–Ru oxides as cathode catalysts show a higher discharge voltage plateau and a higher specific capacity of 6500 mA h gcarbon−1 than those with Ketjen black (KB) alone, and the subsequent charge voltage is ca. 500 mV lower than that with KB. Moreover, much enhanced cyclability of Li–O2 batteries is achieved with a capacity retention ratio of 73.2% after 5 cycles. The cyclability is maintained for 50 cycles without sharp decay under a limited discharge depth of 1100 mA h gcarbon−1, suggesting that such a bifunctional electrocatalyst is a promising candidate for the air electrode in Li–air batteries.

A sensitive DNA biosensor based on dual-amplification of thrombin and thiocyanuric acid-gold nanoparticle (TCA-AuNP) network is developed. First, the sandwich hybridization is formed by the capture probe immobilized on the surface of magnetic beads (MBs), the target DNA and the reporter probe loaded on PbS nanoparticles (PbS NPs). The PbS NPs contain two kinds of DNA sequences, one is the reporter probe complementary to the target DNA, and the other is the thrombin aptamer I. Through the specific recognition for thrombin, thrombin aptamer II labeled gold nanoparticles are linked to the sandwich complex, and further fabricate a network with TCA. AuNPs are released and dissolved into Au(3+), which catalyzes luminol chemiluminescence (CL) reaction. Due to the dual-amplification effects of thrombin-labeled PbS NPs and the TCA-AuNP network, a significant sensitivity enhancement of this DNA biosensor could be obtained, in the range of 2.0 x 10(-16) M to 3.5 x 10(-14) M, with a limit of detection (LOD) as low as 1.0 x 10(-16) M.

A multifunctional electrochemical strategy based on a dual-aptamer for the detection of adenosine and thrombin in one-pot was developed, by coupling the enhancement of bio-bar-code technology and anodic stripping voltammetry (ASV).

Hummer's method is one of most frequently used methods to prepare graphite oxide (GO), an intermediate of graphene nanosheets. The treatment of wastewater containing a large amount of Mn ion and acid produced in this method is very important to protect the environment and use resources efficiently. In this report, facile treatment of wastewater produced in Hummer's method was proposed to remove strong acid and transform Mn ion into Mn3O4 nanoparticles. The as-prepared Mn3O4 nanoparticles have been characterized with X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectrum (FTIR). Their electrochemical performance as cathode material in an asymmetric supercapacitor was also investigated. The primary electrochemical experiment has shown that as-prepared Mn3O4 exhibited good electrochemical performance.