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Based on DFT calculations, the mechanisms of Li+ diffusion and desorption in adsorbent are revealed by preparing materials with different exposed crystal facets.

Contamination and waste heat are major issues in water pollution. Aiming at efficient synchronous recovery wastewater and waste heat, we designed a novel CaCO3-based phase-change microcapsule system with an n-docosane core and a CaCO3/Fe3O4 composite shell. The system was fabricated through an emulsion-templated in situ precipitation approach in a structure-directing mode, resulting in a controllable morphology for the resultant microcapsules, varying from a peanut hull through ellipsoid to dumbbell shapes. The system has a significantly enlarged specific surface area of approximately 55 m2·g−1 with the CaCO3 phase transition from vaterite to calcite. As a result, the microcapsule system exhibits improved adsorption capacities of 497.6 and 79.1 mg/g for Pb2+ and Rhodamine B removal, respectively, from wastewater. Moreover, increase in the specific surface area of the microcapsule system with a sufficient latent heat capacity of approximately 130 J·g−1 also resulted in an enhanced heat energy-storage capability and thermal conductance for waste-heat recovery. The microcapsule system also exhibits a good leakage-prevention capability and good multicycle reusability owing to the tight magnetic CaCO3/Fe3O4 composite shell. This study provides a promising approach for developing CaCO3-based phase-change microcapsules with enhanced thermal energy storage and adsorption capabilities for efficient synchronous recovery of wastewater and waste heat.

Modifying the structure of Li1.6Mn1.6O4 (LMO) to enhance its structural stability and adsorption capacity is an effective method to generate materials to recover Li+ ions from mixed solution.

Objectives This study aimed to explore whether icarrin (ICA) can protect cardiomyocytes from hypertension-induced damage by inhibiting endoplasmic reticulum stress (ERS). Methods Spontaneously hypertensive rats (SHRs) were orally administered water or ICA at 10, 20 and 40 mg/kg once daily for 12 weeks, and Wistar–Kyoto (WKY) rats were used as control. Changes in the growth and blood pressure of rats were assessed. Cardiac function was determined by ultrasound and the left ventricle mass was calculated. Myocardial tissue structure was assessed by haematoxylin and eosin staining, cardiomyocyte apoptosis was observed by TUNEL staining and the expression of ERS-related proteins was determined by western blotting. Results In the SHR group, blood pressure was significantly high, left ventricular function decreased and left ventricular mass index increased. Additionally, left ventricular cardiomyocyte hypertrophy, disordered myofilament arrangement and increased cardiomyocyte apoptosis were observed by histological staining. ERS-induced proteins associated with apoptosis, including GRP78, PERK, ATF-6, ATF-4, CHOP, DR5, Caspase 12, c-JUN and ASK-1 were found to be highly expressed. ICA treatment reduced blood pressure and regulated the expression of proteins induced by ERS. Cardiomyocyte apoptosis decreased and left ventricular function improved. Conclusions ICA can inhibit ERS-induced apoptosis of cardiomyocytes and protect ventricular function in SHR.

As a type of promising phase-change materials, sugar alcohols have a great potential for thermal energy storage due to their high energy-storage density. However, the intermolecular hydrogen bondin...

H2TiO3 (HTO) is considered to be one of the most promising adsorbents for lithium recovery from aqueous lithium resources duo to its highest theoretical adsorption capacity.

The adsorption method is a promising route to recover Li+ from waste lithium batteries and lithium-containing brines. To achieve this goal, it is vital to synthesize a stable and high adsorption capacity adsorbent. In this work, Li4Ti5O12 nanorods are prepared by two hydrothermal processes followed by a calcination process. Then the prepared Li4Ti5O12 nanorods are treated with different HCl concentrations to obtain a H4Ti5O12 adsorbent with 5 μm length along the [100] direction. The maximum amount of extracted lithium can reach 90% and the extracted titanium only 2.5%. The batch adsorption experiments indicate that the H4Ti5O12 nanorod maximum adsorption capacity can reach 23.20 mg g−1 in 24 mM LiCl solution. The adsorption isotherms and kinetics fit a Langmuir model and pseudo-second-order model, respectively. Meanwhile, the real adsorption selectivity experiments show that the maximum Li+ adsorption capacity reaches 1.99 mmol g−1, which is far higher than Mg2+ (0.03 mmol g−1) and Ca2+ (0.02 mmol g−1), implying these nanorods have higher adsorption selectivity for Li+ from Lagoco Salt Lake brine. The adsorption capacity for Li+ remains 91% after five cycles. With the help of XPS analyses, the adsorption mechanism of Li+ on the H4Ti5O12 nanorods is an ion exchange reaction. Therefore, this nanorod adsorbent has a potential application for Li+ recovery from aqueous lithium resources.

Modifying the structure of Li

H

We aimed to investigate the effects of bone marrow mesenchymal stem cell conditioned medium (BMSC-CM) in preventing 2,5-hexanedione (HD)-induced damage to motoneurons, and examined the molecular mechanisms that mediate these effects. VSC4.1 cells were exposed to 25 mM HD for 24 h followed by incubation with DMEM for 24 h. HD-treated cells were incubated with BMSC-CM at varied concentrations. Incubation with BMSC-CM ameliorated the decreased cell viability and reduced LDH release from cells exposed to HD. BMSC-CM suppressed the elevated number of autophagic vacuoles, cells with LC3 puncta, increased LC3-II/LC3-I ratio, and decreased p62 caused by HD exposure. BMSC-CM elevated NGF and p-TrkA expressions in HD-treated cells. Administration of NGF inhibited autophagy, an effect that was similar to that observed after BMSC-CM treatment; this effect was abolished by the addition of NGF-neutralizing antibodies. BMSC-CM or NGF elevated p-protein kinase B (Akt) and p-mammalian target of rapamycin (mTOR) in HD-exposed cells, which was interrupted by TrkA inhibitor, K252a and mTOR inhibitor, rapamycin. BMSC-CM prevented HD-induced autophagic cell damage in VSC4.1 cells. The neuroprotective effect of BMSC-CM appeared to be at least partly associated with its ability to trigger the NGF-phosphatidylinositol-3-kinase (PI3K)/Akt/mTOR signaling pathway.

The H1.6Mn1.6O4 (HMO) derived from Li1.6Mn1.6O4 (LMO) has been aroused enormously attention due to high adsorption capacity. Through surface trace doping of F and S (LMO-R, R = F, S), the cycling stabilities and adsorption abilities of Li1.6Mn1.6O4 are improved. The adsorption uptakes are increased from 26.1 mg/g (before doping) to 33.4 and 27.9 mg/g at Li+ concentration of 12 mmol/L, respectively. In addition, first-principles calculations further confirm that F and S substitutes for O at 32e sites, leading to an improvement of the Li+ uptake rate. The Li+ adsorption capacities in the cycling process are enhanced by F and S doped, which may result from improving the charge density and offering more charge carriers that can participate in the ad/desorption reaction. The effect of the F and S substitution on adsorption capacity is discussed.

The adsorption method is a promising route to recover Li

A spraying method has been employed to prepare silica-based superhydrophobic coatings on AZ31B Mg alloy surfaces. Both nanometer and micrometer silica particles were used to construct the micrometer and nanometer scale binary structures, and 1H, 1H, 2H, 2H-Perfluorooctyltriethoxysilane (PFOTES) was used as the fluorine silane coupling agent. The coatings were characterized using the techniques of Field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), and Fourier transform infrared (FTIR) spectra. The corrosion resistance properties of the prepared superhydrophobic surfaces were checked based on polarization curves. And their wetting properties were studied for aqueous solutions of HCl, NaOH, NaCl, MgCl2, NaI, CH3COONa, C2H5OH, C17H33COONa, and sodium dodecylbenzene sulfonate, respectively, with contact angle and sliding angle as the parameters. In contrast with the bare magnesium alloy AZ31B, after coating, the corrosion current density shows a more than three-order of magnitude smaller value, and the water contact angle increases from ∼32° to over 155°. Solution pH and coexisted NaCl, MgCl2, NaI, and CH3COONa salts have little effect on the wetting properties of the prepared superhydrophobic surfaces. On the contrary, coexisted C2H5OH, C17H33COONa, or sodium dodecylbenzene sulfonate has an obvious effect on the wetting properties. The differences in the wetting properties were explained by considering the interactions between the superhydrophobic surfaces and the surfaces of the solution droplets. In addition, the superhydrophobicity coating also exhibited good mechanical, chemical and environment stability in the abrasion test, immersion test, salt spray test, etc.

Industrial grinding processes always involve multiple sequential passes, such as rough, semi-rough, semi-finish, finish, and spark-out, for the surface and geometrical accuracy generation. The design of multi-pass grinding process parameters usually requires in-depth heuristic knowledge or complex process modeling. However, when multiple process output objectives must be achieved, either heuristic knowledge or analytical modeling is incapable in dealing with the large number of process parameters or decoupling the dependency of individual pass with its neighboring passes. In this paper, a hybrid Non-dominated Sorting Firefly Algorithm (NSFA) is proposed by incorporating the non-dominated sorting algorithm with the firefly algorithm. The developed NSFA is capable in searching the optimal whole set of grinding process parameters at improved convergence speed and with less iterations, which is proved by comparing with Non-dominated Genetic Algorithm (NSGA-II) and Non-dominated Particle Swarm Optimization (NSPSO). Finally, a variable-pass internal grinding for engineering ceramics is carried out to verify the efficacy of the proposed NSFA. With the process output objectives of minimal grinding time and geometric error, the optimized process by the NSFA can realize the achievement of all process quality objectives simultaneously with the grinding efficiency increased by 32.4%.

A simple and practical spray method is employed to prepare a PVDF/PFOTES-SiO2 superhydrophobic composite coating on the AZ31B Mg alloy substrate. The morphology, composition, and water contact angle (CA) were measured by Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscope (FESEM) and contact angle measuring instrument. Hydrophilic nano-SiO2 is modified by PFOTES to obtain hydrophobicity. The influence of the mass of PFOTES-SiO2 to PVDF on the hydrophobic properties was studied. The wear resistance and stability of the composite coating have been investigated by immersion test, cross-cut adhesion test and friction test. Additionally, the corrosion resistance was measured by electrochemical workstation and salt spray corrosion test. The CA of PVDF/PFOTES-SiO2 coating is 161.3° and the sliding angle (SAs) is less than 2°. After 10× the sandpaper friction test, the superhydrophobic contact angle of the coating remained above 155°, and the sliding angle was less than 5°, which indicated that the prepared coating is a strong superhydrophobic coating with good wear resistance. The results of the electrochemical tests show that the superhydrophobic coating improved the anti-corrosion performance of Mg alloy, and the water contact angle is greater than 150° after 168 h salt spray corrosion test. Due to its excellent superhydrophobicity, wear resistance and anti-corrosion properties, the robust PVDF/PFOTES-SiO2 coating is considered to have great potential for future applications in the automotive and marine industries.

Inorganic salt hydrates have a great potential for solar photothermal energy storage due to their high energy-storage density and low cost. However, there are some major drawbacks such as high supercooling degree, shape/form instability, phase segregation, and poor long-term durability found in salt hydrates. These greatly limit their practical applications. Herein, we designed and fabricated a type of eco-friendly and cost-efficient phase-change system based on sodium acetate trihydrate (SAT) as an inorganic phase change material and biomass-derived carbonaceous sheets (BDCSs) as a supporting material for high-efficient solar photothermal energy storage and shape stabilization. Derived from a biomass waste of watermelon rind, the BDCSs show some unique characteristics such as a stacking lamellar structure and a compact surface with some corrugations and ripples as well as the presence of abundant oxygen-rich groups. These can lead to a significant enhancement in photothermal conversion efficiency of solar energy when used as a supporting material for a SAT-based phase-change composite system. This type of composite system not only presents a high thermal energy capacity of 212.2 J/g and a very low supercooling degree of 0.9 °C, but also has a high photothermal conversion efficiency of up to 80.18% for solar energy. Moreover, the composite system exhibits high thermal conductance, good shape stability without phase segregation, and excellent thermal cycle stability for long-term solar photothermal energy storage and release. This study provides a simple and facile methodology for the development of bio-based phase-change composites for high-efficient solar energy utilization.

Manganese based ion-sieves, particularly Li1.6Mn1.6O4, can be used to recover Li+ from salt lakes due to their excellent adsorption and anti-dissolution properties. Generally, the element doping can only improve the adsorbent capacity or enhance the structural stabilities. In this work, the adsorption capacity of Li1.6Mn1.6O4 is improved from 33.4 to 40.9 mg/g (c(LiCl) = 24 mmol/L) via trace surface doping of Al (LMO-Al), likely owing to the partial substitution of Mn’s 16d sites by Al3+. Furthermore, the dissolution of Mn in Li1.6Mn1.6O4 is reduced from 5.4% (before doping) to 2.1%, which may due to stronger Al3+ and O2− chemical bond and improving the amounts of Mn4+. In addition, Al doping allowed for the reduction of the dissolution loss rate of Mn during cycling, which greatly increases the possibility in practical application.

The improved adsorption capacities by increasing specific surface area methods are merely reached about 50% of H4Ti5O12’s theoretical adsorption capacity, and the adsorption behavior and mechanism of lithium on special facets of H4Ti5O12 remain unclear. In this study, a flower-shaped Li4Ti5O12 and an octahedral Li4Ti5O12 were prepared with the specific surface areas of 176.23 and 83.02 m2/g, and the corresponding adsorption behaviors of the obtained adsorbents exposed with (1 1 0) and (1 1 1) facets were investigated by using experimental and computational methods. The maximum Li+ uptake values on H4Ti5O12 (1 1 0) and H4Ti5O12 (1 1 1) are 26.85 mg/g and 33.56 mg/g at 45 °C in 24 mM LiCl solutions, respectively. The fifth reuse ability of H4Ti5O12 (1 1 1) still remains 88.9% of the original’s, which is higher than H4Ti5O12 (1 1 0) (76.3%). Although with lower specific surface area, the octahedral H4Ti5O12 have higher ions selectivity, greater adsorption capacity, and better reuse ability than flower-shaped H4Ti5O12, which may due to the special (1 1 1) facet exposed. Firstly, H4Ti5O12 (1 1 1) owned small hole sizes can inhibit other ions diffusing into H4Ti5O12 and improve the ion selectivity. Secondly, the immigration paths by the First-principles calculations revealed that the Li+ migrate onto the Li4Ti5O12 (1 1 1) is easier to than Li4Ti5O12 (1 1 0) through 8a-16c-8a-16c sites. At last, [Li(H2O)4]+ can form the stable complexes and its adsorption energies on (1 1 1) are higher than on (1 1 0) facets, which may lead to larger adsorption capacity and better reuse ability. This work will help to understand the [Li(H2O)4]+ adsorption behavior and mechanism on different crystal facets by experiments and computations.

2,5-hexanedione (HD) is the ultimate neurotoxic metabolite of hexane, causing the progression of nerve diseases in human. It was reported that HD induced apoptosis and oxidative stress. Taurine has been shown to be a potent antioxidant. In the present study, we investigated the protection of taurine against HD-induced apoptosis in PC12 cells and the underlying mechanism. Our results showed the decreased viability and increased apoptosis in HD-exposed PC12 cells. HD also induced the disturbance of Bax and Bcl-2 expression, the loss of MMP, the release of mitochondrial cytochrome c and caspase-3 activation in PC12 cells. Moreover, HD resulted in an increase in reactive oxygen species (ROS) level and a decline in the activities of superoxidedismutase and catalase in PC12 cells. However, taurine pretreatment ameliorated the increased apoptosis and the alterations in key regulators of mitochondria-dependent pathway in PC12 exposed to HD. The increased ROS level and the decreased activities of the antioxidant enzymes in HD group were attenuated by taurine. These results indicate that pretreatment of taurine may, at least partly, prevent HD-induced apoptosis via inhibiting mitochondria-dependent pathway. It is also suggested that the potential of taurine against HD-induced apoptosis may benefit from its anti-oxidative property.

2,5-Hexanedione (HD) is an important bioactive metabolite of n-hexane, which mediates the neurotoxicity of the parent compound. Increasing evidence suggests that over-activated autophagy can lead to autophagic neuronal death; however, whether the excessive autophagy is involved in HD-induced neurotoxicity remains unknown. To investigate the effect of HD on autophagy and to find its underlying mechanism, we respectively treated VSC4.1 cells with 5, 15 and 25 mM HD for 24 h. Our results show that HD induced excessive autophagy of VSC4.1 cells in a dose-dependent manner, also, the over-activated autophagy was significantly mitigated in the presence of PI3K activator or Akt activator or mTOR activator. These results indicate that HD induces excessive autophagy of VSC4.1 cells by repressing the PI3K/Akt/mTOR signaling pathway. LDH assay showed that HD contributed to a concentration dependent increase in VSC4.1 cell death, which was significantly reduced by the administration of PIK-III, an autophagy inhibitor. These results also indicate that HD induces autophagic death of VSC4.1 cells via the signaling pathway.

The time-dependent performance of grinding is expressed as the change of process output measures as a function of time during grinding. Although the wheel capability will be restored by dressing, the time-dependent performance of grinding during one dressing skip is the determinant on the grinding quality variation in terms of surface integrity and workpiece geometric accuracy. Therefore, understanding of grinding time-dependent performance in relation with the wheel–workpiece microscopic interaction is critical for wheel and process development to achieve stable grinding processes. In this article, the grinding of superalloy with cubic boron nitride (cBN) grinding wheels is performed. The time-dependent performance is recorded to represent the characteristic features, and the microscopic wheel topography is measured under scanning electron microscope (SEM) throughout the grinding process, so as to reveal the root cause for the time-dependent performance and its impact on the workpiece quality var...

As a manganese-based Li+ ion sieve, H1.6Mn1.6O4 has the highest theoretical adsorption capacity drive from Li1.6Mn1.6O4. However, its industrial application is limited by large dissolution of Mn in the pickling process. In this work, we improved the Li+ adsorption and anti-dissolution properties by doping Li1.6Mn1.6O4 with different transition metal ions (Fe3+, Co2+). The characterization results of the materials indicated that no new impurities were introduced during the doping process (XRD) and a few Mn3+ was exist in the doped Li1.6Mn1.6O4 (XPS). The adsorption results shown that the adsorption capacities are 35.3 mg/g and 35.4 mg/g after doping with Fe3+ and Co2+ individually. Compared with undoped adsorbent (32.3 mg/g), these adsorption capacities of doping adsorbents are increased (CLi+ = 12 mmol/L; pH 12 t = 48 h). In the same time, the dissolution of Mn was 3.95% and 4.42% (CHCl = 0.6 mmol/L t = 24 h), which are improved the structure stability compared to undoped adsorbents (5.43%). The anti-dissoultion property of Ni doped Li1.6Mn1.6O4 does not improved maybe due to the severe cell expansion.

Chronic exposure to n-hexane, a widely used organic solvent in industry, induces central-peripheral neuropathy, which is mediated by its active metabolite, 2,5-hexanedione (HD). We recently reported that transplantation of bone marrow-mesenchymal stem cells (BMSC) significantly ameliorated HD-induced neuronal damage and motor deficits in rats. However, the mechanisms remain unclear. Here, we reported that inhibition of HD-induced autophagy contributed to BMSC-afforded protection. BMSC transplantation significantly reduced the levels of microtubule-associated protein 1 light chain 3-II (LC3-II) and the degradation of sequestosome-1 (p62) in the spinal cord and sciatic nerve of HD-intoxicated rats. Downregulation of autophagy by BMSC was also confirmed in VSC4.1 cells exposed to HD. Moreover, inhibition of autophagy by PIK III mitigated the neurotoxic effects of HD and, meanwhile, abolished BMSC-afforded neuroprotection. Furthermore, we found that BMSC failed to interfere with Beclin 1, but promoted activation of mammalian target of rapamycin (mTOR). Unc-like kinse 1 (ULK1) was further recognized as the downstream target of mTOR responsible for BMSC-mediated inhibition of autophagy. Altogether, BMSC transplantation potently ameliorated HD-induced autophagy through beclin 1-independent activation of mTOR pathway, providing a novel insight for the therapeutic effects of BMSC against n-hexane and other environmental toxicants-induced neurotoxicity.

In this work, new aliphatic polyetheresteramide copolymers based on e-caprolactone, 11-aminoundecanoic acid, and poly(ethylene glycol) (PEG) were synthesized by the melt polycondensation method. The copolymers obtained were characterized by 1H NMR, differential scanning calorimetry, thermogravimetric analysis/differential thermogravimetry, and wide-angle X-ray diffraction. Water absorption and hydrolytic degradation behavior was also studied. With the increase in PEG content, water absorption and the hydrolytic degradation rate increased accordingly.