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Per- and polyfluoroalkyl substances (PFASs) are persistent and bio-accumulative substances that have many adverse effects on human bodies. This study investigated the PFASs distribution characteristics in urine samples of workers from an acrylic fiber plant and a chemical plant. It was found that perfluorobutanoic acid (PFBA) was the predominant PFASs both in urine samples from the chemical plant (detection frequency: 86.52%; median value: 39.01 ng/mL) and the acrylic fiber plant (detection frequency: 88.16%; median value: 44.36 ng/mL). Meanwhile, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) were detected with very low frequencies and low concentrations. Furthermore, the results showed that PFASs levels in urine samples of workers from different units of the plants were quite different. PFASs concentrations of urine samples in males were higher than those in females, especially for PFBA, PFHxA, and PFDoA. The age had limited effects on the PFASs distribution in urine samples in this study, as short-chain PFASs were the dominant compounds. The correlations between PFASs concentrations in urine and gender/ages of workers were finally analyzed by Person correlation. The overall results may indicate that short-chain PFASs (such as: PFBA and PFBS) were becoming dominant for human exposure, especially occupational workers.

As one of the extensively used feed additives in livestock and poultry breeding, p-arsanilic acid (p-ASA) has become an organoarsenic pollutant with great concern. For the efficient removal of p-ASA from water, the combination of chemical oxidation and adsorption is recognized as a promising process. Herein, hollow/porous Mn-Fe-mixed oxide (MnFeO) nanocubes were synthesized and used in coupling with peroxymonosulfate (PMS) to oxidize p-ASA and remove the total arsenic (As). Under acidic conditions, both p-ASA and total As could be completely removed in the PMS/MnFeO process and the overall performance was substantially better than that of the Mn/Fe monometallic system. More importantly, an interface-promoted direct oxidation mechanism was found in the p-ASA-involved PMS/MnFeO system. Rather than activate PMS to generate reactive oxygen species (i.e., SO4·-, ·OH, and 1O2), the MnFeO nanocubes first adsorbed p-ASA to form a ligand-oxide interface, which improved the oxidation of the adsorbed p-ASA by PMS and ultimately enhanced the removal of the total As. Such a direct oxidation process achieved selective oxidation of p-ASA and avoidance of severe interference from the commonly present constituents in real water samples. After facile elution with dilute alkali solution, the used MnFeO nanocubes exhibited superior recyclability in the repeated p-ASA removal experiments. Therefore, this work provides a promising approach for efficient abatement of phenylarsenical-caused water pollution based on the PMS/MnFeO oxidation process.

Pharmaceuticals, such as over-the-counter (OTC) medicines, may be an important source of human exposure to several endocrine disruptors, though unnoticed to date. In the present study, we investigated the presence of six parabens and nine bisphenol A (BPA) and its analogues in OTC medicines manufactured in China. Parabens and bisphenols were present in more than 90% of the samples. The total measured concentrations of parabens and bisphenols were in the range of non-detectable (ND) to 213 ng/g and ND to 415 ng/g, respectively. Regarding parabens, methyl paraben (MeP) was the predominant analog, accounting for 43 ± 36% of the total amount, followed by ethyl paraben (EtP) (39 ± 35%), and others (< 10%). Bisphenol F and BPA were the predominant bisphenols, accounting for 24 ± 28% and 22 ± 26% of the total amount, respectively. The median values of estimated daily intakes (EDIs) of parabens and bisphenols were the highest for infants (2.96 and 3.14 ng/kg_bw/day, respectively) and the lowest for adults (0.69 and 0.25 ng/kg_bw/day, respectively); moreover, the EDIs of parabens and bisphenols were higher in Chinese patent medicines than in western pediatric medicines. The hazard quotient (HQ) for sum of MeP and EtP (∑(MeP + EtP)) and BPA in three age groups were within the safe zone (HQ < 0.0004). Monte Carlo simulation was applied to predict the human exposure risk of parabens and bisphenols. The predicted ranges of EDIs of parabens and bisphenols were much wider, and the extreme predicted values were observed in all four age groups, which were higher than the acceptable daily intake. The extreme predicted values of ∑(MeP + EtP) and BPA were indicative of carcinogenic risk in toddlers. These results implied potential risks for the Chinese people existed. Considering the huge export of Chinese traditional medicines and western medicines worldwide, and easy access to OTC medicines for the general population, the presence of parabens, bisphenols, and other environmental contaminants in medicines still need to be monitored.

Transition metal (TM)-based bimetallic spinel oxides can efficiently activate peroxymonosulfate (PMS) presumably attributed to enhanced electron transfer between TMs, but the existing model cannot fully explain the efficient TM redox cycling. Here, we discover a critical role of TM-O covalency in governing the intrinsic catalytic activity of Co3-x Mnx O4 spinel oxides. Experimental and theoretical analysis reveals that the Co sites significantly raises the Mn valence and enlarges Mn-O covalency in octahedral configuration, thereby lowering the charge transfer energy to favor MnOh -PMS interaction. With appropriate MnIV /MnIII ratio to balance PMS adsorption and MnIV reduction, the Co1.1 Mn1.9 O4 exhibits remarkable catalytic activities for PMS activation and pollutant degradation, outperforming all the reported TM spinel oxides. The improved understandings on the origins of spinel oxides activity for PMS activation may inspire the development of more active and robust metal oxide catalysts.

Rechargeable batteries are promising platforms for sustainable development of energy conversion and storage technologies. Highly efficient multifunctional electrodes based on bimetallic sulfides for rechargeable batteries are extremely desirable but still challenging to tailor with controllable phase and structure. Here, we report a colloidal strategy to fabricate FeCo-based bimetallic sulfides on reduced graphene oxide (rGO), which are expected to display highly efficient oxygen electrocatalysis and sodium storage performances. Specifically, as-screened FeCo8S8 nanosheets (NSs) on rGO originating from suitable tailoring of the Co9S8 matrix with Fe at the atomic level exhibited a very low potential difference (0.77 V) at 10 mA cm-2 and negligible voltage loss after 200 cycles as an air electrode for Zn-air batteries. For Na-ion batteries, FeCo8S8 NS/rGO demonstrated a superior high-rate capability (188 mAh g-1 at 20 A g-1) with long-term cycling stability. The bifunctional electrocatalytic property and sodium storage performance are attributed to not only the synergistic effect of Fe/Co but also the optimized catalytic activity and ion transport ability by the in situ rGO hybrid. This work demonstrates the potential applications of FeCo-based bimetallic sulfides as efficient electrode materials for both rechargeable Zn-air and Na-ion batteries.

Phthalates are plasticizers in various products and regarded as endocrine disruptors due to their anti-androgen effects. Environmental occurrence and toxicities of parent phthalates have been widely reported, while the current state of knowledge on their metabolites is rarely summarized. Based on the available literature, the present review mainly aims to 1) characterize the potential metabolites of phthalates (mPAEs) using the pharmacokinetics evidences acquired via animal or human models; 2) examine the molecular and cellular mechanism involved in toxicity for mPAEs; 3) investigate the exposure levels of mPAEs in different human specimens (e.g., urine, blood, seminal fluid, breast milk, amniotic fluid and others) across the globe; 4) discuss the models and related parameters for phthalate exposure assessment. We suggest there is subtle difference in toxic mechanisms for mPAEs compared to their parent phthalates due to their alternative chemical structures. Human monitoring studies performed in Asia, America and Europe have provided the population exposure baseline levels for typical phthalates in different regions. Urine is the preferred matrix than other specimens for phthalate exposure study. Among ten urinary mPAEs, the largest proportions of di-(2-ethylhexyl) phthalate (DEHP) metabolites (40%), monoethyl phthalate (mEP) (43%) and DEHP metabolites/mEP (both 29%) were observed in Asia, America and Europe respectively, and mono-5-carboxy-2-ethypentyl phthalate was the most abundant compounds among DEHP metabolites. Daily intakes of phthalates can be accurately calculated via urinary mPAEs if the proper exposure parameters were determined. Further work should focus on combining epidemiological and biological evidences to establish links between phthalates exposure and biological phenotypes. More accurate molar fractions (FUE) of the urinary excreted monoester related to the ingested diesters should be collected in epidemiological or pharmacokinetic studies for different population.

We spend more than half of our daily time in indoor environments, and the contributions of phthalates present in it to total exposure are important. Here, we determined phthalate concentrations in paired indoor settled dust/air and their metabolites in human urine from 100 general families in south China to explore such kind of effect. The total concentrations of phthalates/metabolites were 48.7-2850 μg/g, 279-5080 ng/m3 and 10.7-2840 ng/mL in the indoor dust, air and urine samples, respectively. Among all targets, di-n-butyl phthalate, di-isobutyl phthalate and di-(2-ethylhexyl) phthalate and their metabolites were the predominant compounds. The daily intakes (DIs) of phthalates via dust or air decreased with age, except for infant, and the values of dust ingestion, air inhalation and air dermal uptake were 2720 ± 2460, 1300 ± 973 and 3590 ± 2890 ng/kg/day for toddlers and 236 ± 194, 360 ± 179 and 1120 ± 586 ng/kg/day for adults, respectively. The ratios of DIs from air to dust were greater than 1.0 for people in all age groups, and the ratio was the highest for adults. Furthermore, the contributions of phthalates from indoor dust and air to total DIs from all sources (estimated from urinary phthalate metabolites) were 0.60%-5.23% and 2.65%-12.2% for different ages, respectively. Our results indicated that indoor air was a quite important source for human exposure to phthalates in indoor environment in south China.

Bismuth oxychloride (BiOCl) is a typical UV-light-sensitive photocatalyst with a unique layered structure, but exhibits no response towards visible light. This is a main limitation for its practical applications in photocatalytic degradation of pollutants. Among various methods to expand the light absorption region, doping modification is an efficient approach because it can tailor the band structure by forming a doping energy level without changing the layered structure substantially. In this case, the static electric field in the BiOCl crystal can be retained. Since cobalt (Co) exhibits good electrochemical properties, it is an ideal element for doping modification to expand the light absorption region and enhance the charge separation efficiency of BiOCl. In this work, Co-doped BiOCl nanosheets were prepared using a simple hydrothermal route. The doped Co expanded the light absorption region and enhanced the charge separation efficiency by forming a doping energy level in the band gap of BiOCl. As a result, the Co-BiOCl nanosheets exhibited an outstanding photocatalytic performance in degrading bisphenol A (BPA) under visible light irradiation with a degradation rate of 3.5 times higher than that of BiOCl. On the basis of the experimental results and density functional theory calculations, the mechanism of visible-light-driven catalytic BPA degradation by the Co-BiOCl nanosheets was elucidated. Therefore, the feasibility of Co-doping modification for BiOCl was confirmed, and a novel and efficient strategy was provided for the design and synthesis of high-performance photocatalysts.

From the roots of Aconitum brachypodum Diels., twelve diterpenoid alkaloids, such as bullatine H (1), 16, 17-dihydroxylepenine (2), N-ethyl-1α-hydroxydictizine (3), bullatine A (4), lepenine (5), 12-epi-napelline (6), songoramine (7), aconine (8), N-deethyldeoxyaconitine (9), aconitine (10), N-deethyl-3-acetylaconitine (11) and N-deethylaconitine (12) were isolated and identified. Structure elucidation of these compounds was performed on the basis of NMR spectroscopic data. Compounds 2, 3, 6, 7, 9 and 12 were obtained from this species for the first time. Chemotaxonomic significance of these compounds is described herein.

Introducing reductive species into heterogeneous catalysts can improve their catalytic efficiency in Fenton-like processes. Iodide ions (I−), a typical reductive species with good reducibility, might enhance the catalytic performance of H2O2 activation when doped in heterogeneous catalysts. In this study, the iodine-doped Bi2WO6 (IX-Bi2WO6) nanosheets were synthesized with a facile hydrothermal method and used to activate H2O2 to degrade bisphenol A (BPA). Compared with Bi2WO6, which was almost inactive, the IX-Bi2WO6 exhibited great improvement for BPA degradation. Among the fabricated catalysts, the I0.50-Bi2WO6 with an iodine content of 0.50 mmol was found to be most effective and could work efficiently in a wide pH range from 4.0 to 10.0. Moreover, with a low consumption of H2O2 (H2O2 : pollutant molar ratio = 10:1), 78% BPA was degraded within 10 min at initial pH 7.0. Unlike the conventional H2O2 activation mechanism, the direct electron transfer was verified to be the main mechanism for the BPA degradation based on the results of electron paramagnetic resonance (EPR) analysis, radical quenching, and electrochemical experiments in this work. Furthermore, the activation of H2O2 by iodine-doped BiVO4 and Bi2MoO6 was also conducted to validate the applicability of such an iodine doping approach. These results indicate that the introduction of reductive species I− is a promising and effective method to develop highly efficient Bi-based catalysts for H2O2 activation.

Iron-nickel-based electrocatalysts are a group of noble-metal-free and high-performance candidate for oxygen evolution reaction (OER), and autoxidation always occurs in their OER process. Autoxidation is a double-edged sword: it could in-situ generate high-catalytic activity sites to accelerate OER, but it also results in the attenuation of conductivity and the dissolution of active components. In this work, we propose a new strategy to relieve the negative impacts of autoxidation on OER through designing three-dimensional (3D) iron-nickel sulfide nanosheets/reduced graphene oxide (FeNiS2 NS/rGO) nanohybrids via a one-pot colloidal method, which enabled the well dispersion and strong coupling of FeNiS2 NS on the rGO. Such an interconnected 3D architecture could facilitate excellent electron transport, provide large amounts of active sites and prevent the dissolution of active components. The FeNiS2 NS/rGO delivered extremely low overpotentials of 270 mV and 200 mV to reach a current density of 10 mA cm−2, and rapid kinetics with Tafe slope of 38 mV dec−1 and 40 mV dec−1 for OER in 0.1 and 1.0 M KOH, respectively. Moreover, they could retain a great stability without activity loss over long-term continuous electrolysis and long-ageing time under air conditions. This work provides an efficient approach to resolve the autoxidation problem of FeNiS2 NS in the OER process and develops a promising earth-abundant OER electrocatalyst towards practical applications.

Visible-light-responsive photocatalysis offers exciting opportunities for sustainable environmental pollution control, but the unsatisfactory photoactivity of the existing photocatalysts impedes their practical application. Here, we fabricated a high-activity mesoporous carbon nitride nanosphere (MCNS) photocatalyst by a hard template synthesis method through incomplete polycondensation of the cyanamide precursors during thermal polymerization. The MCNS showed a unique nanosphere structure with a larger specific surface area and possessed more abundant cyano groups than two other graphitic carbon nitride (g-C3N4) materials (i.e., nanosheet and bulk g-C3N4). Experimental results and theoretical calculations indicate important roles of the cyano groups in narrowing the catalyst band gap to favor visible light absorption and accelerating the separation of the electron–hole pairs. With such superior surface properties and improved charge separation efficiency, the MCNS exhibited 14.7 times higher photocatalytic activity for bisphenol A (BPA) degradation than the bulk g-C3N4. The MCNS also showed good stability during repeated use. Therefore, the as-prepared MCNS has great potential for visible-light-responsive photocatalysis in environmental remediation and other photocatalytic applications.

Currently the dewatering of activated sludge from wastewater treatment plants is a problem not well solved. Extracellular polymeric substances (EPS), including loosely bound EPS (LB-EPS) and tightly bound EPS (TB-EPS), are highly hydrated biopolymers and play important roles in sludge dewatering. In the present work, two types of treatments, i.e., salt addition and pH modification, were proposed to evaluate the effects of bound water content and its distribution on the dewatering performance of activated sludge. Results show that the bound water content in activated sludge was deeply related to the floc structures and EPS compositions. Both salt addition and acid treatment altered the flocculated matrix and increased the contents of LB-EPS, resulting in the release of trapped water and reduction in sludge volume. In addition, the chemical treatments also affected the distribution of bound water. The internal water content increased upon the dose of NaCl, leading to a decreased water content trapped in EPS. Hence, salt addition caused a slower filtration rate, but did not effectively decrease the total water content, although the EPS were decomposed. Under acidic conditions, cell lysis helped to release the intracellular water and further enhance the sludge dewatering performance. In contrast, conditioning with low-dosage alkali increased the bound water content and deteriorated the sludge dewaterability. Therefore, an in-depth investigation into the mechanisms is useful to optimize the activated sludge dewatering process.

Due to the large number of ionic liquids (ILs) and their potential environmental risk, assessing the toxicity of ILs by ecotoxicological experiment only is insufficient. Quantitative structure-activity relationship (QSAR) has been proven to be a quick and effective method to estimate the viscosity, melting points, and even toxicity of ILs. In this work, the LC50 values of 30 imidazolium-based ILs were determined with Caenorhabditis elegans as a model animal. Four suitable molecular descriptors were selected on the basis of genetic function approximation algorithm to construct a QSAR model with an R2 value of 0.938. The predicted lgLC50 in this work are in agreement with the experimental values, indicating that the model has good stability and predictive ability. Our study provides a valuable model to predict the potential toxicity of ILs with different sub-structures to the environment and human health.

Soluble amyloid beta (Aβ) is believed to contribute to cognitive deficits in the early stages of Alzheimer's disease (AD). Increased soluble Aβ1-42 in the hippocampus is closely correlated with spatial learning and memory deficits in AD. Riluzole (RLZ), an FDA-approved drug for amyotrophic lateral sclerosis (ALS), has beneficial effects for AD. However, the mechanism underlying the effects remains unclear. In this study, its neuroprotective effect against soluble Aβ1-42-induced spatial cognitive deficits in rats was assessed. We found that intrahippocampal injection of soluble Aβ1-42 impaired spatial cognitive function and suppressed long-term potentiation (LTP) of the DG region, which was relevant to soluble Aβ1-42-induced shift of the hippocampal excitation/inhibition balance toward excitation. Interestingly, RLZ ameliorated Aβ1-42-induced behavioral and LTP impairments through rescuing the soluble Aβ1-42-induced excitation/inhibition imbalance. RLZ attenuated Aβ1-42-mediated facilitation of excitatory synaptic transmission by facilitating glutamate reuptake and decreasing presynaptic glutamate release. Meanwhile, RLZ attenuated the suppression of inhibitory synaptic transmission caused by Aβ1-42 by potentiating postsynaptic GABA receptor function. These results suggest that RLZ exerts a neuroprotective effect against soluble Aβ1-42-related spatial cognitive deficits through rescuing the excitation/inhibition imbalance, and it could be a potential therapy for AD.

A comparative study of internal and external exposure is a good method to comprehensively understand human exposure to environmental contaminants that may trigger oxidative stress in human body. Information is limited regarding the influences of reactive oxygen species (ROS) on human health from the environment. In addition, data on the contribution of polycyclic aromatic hydrocarbons (PAHs) from indoor environments, especially air, to total human exposure are still insufficient. The present study measured PAHs in paired indoor dust (n = 101), gas (polyurethane foams, n = 100), and particle samples (quartz fiber filters, n = 100) and their hydroxy metabolites (OH-PAHs) in 205 urine samples from 101 families in Guangzhou, South China. The oxidative potential (OP) in dust samples was quantified with a dithiothreitol (DTT) assay to reflect the oxidizability of ROSs, and explore the relationship between environmental ROSs and oxidative stress in humans (using urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG) as a biomarker). The estimated daily intakes (EDIs) of Σ16PAH via air inhalation were much higher than those from gas dermal contact, dust dermal contact, and dust ingestion (mean: 19.5 > 4.27 > 3.75 > 1.60 ng/kg_bw/day). Generally, approximately 16% of naphthalene, 28% of fluorene, 9% of phenanthrene, and 3% of pyrene were derived from indoor environments for all residents when compared with the total PAH exposure amount from all sources. Significantly positive relationships were found between OH-PAHs and 8-OHdG (coefficients β: 0.129–0.366, p

Peroxymonosulfate (PMS)-based advanced oxidation processes (AOPs) for wastewater treatment have recently attracted widespread interests. However, the degradation of organic pollutants via traditional radical-dominated pathway is severely limited by the side reactions between radicals and the co-existing inorganic anions, especially under high salinity conditions. Herein, an efficient Fe/O co-doped g-C3N4nanosheet catalyst was synthesized to dominantly activate PMS through a dual non-radical pathway with the singlet oxygen and high-valent iron-oxo species (Fe(V)=O). The rapid degradation of model pollutant bisphenol A (BPA) was achieved by dosing PMS (1 mM), catalyst (0.1 g/L) in a simulated high-salt wastewater (≥200 mM) of the developed Fe/O-doped g-C3N4+PMS system with a reaction rate constant of 1204-fold higher than that in g-C3N4+PMS system. The O and Fe co-dopants could reconfigurate the electronic structure of pristine g-C3N4 to produce more non-radical active species. The formed Fe(V)=O played a main role in the BPA degradation by promoting electron transfer from BPA molecule to the "metastable PMS/catalyst complex", which was verified by electrochemical tests and density functional theory calculations. The auxiliary transient productions of ·OH+SO4·- species were also favorable for the pollutant degradation. Excellent reusability in a wide pH range confirmed the practical application prospects of the Fe/O-doped g-C3N4+PMS system. The successive addition of PMS with a low dosage into the system rich in pollutants was confirmed to favor the PMS utilization. Our work unveils the potential applications of a non-radical dominated process for the decontamination of organic pollutants in saline water.

FeNi-based nanomaterials with bimetallic alloying effect deliver a great promise as an efficient electrocatalyst for oxygen evolution reaction (OER). However, the reconstruction to generate in-situ catalytically FeNi-based oxides or hydroxides during OER process and high electrical conductivity demand foster the great pursuit of the rational design of FeNi-based OER electrocatalyst a big challenge. Herein, we design and fabricate a nanostructured metallic FeNi2S4 as a highly efficient OER electrocatalyst. This catalyst exhibits an overpotential of (250 mV) and a Tafel slope (62 mV dec−1), that outperforms the benchmark of commercial RuO2. The experimental results demonstrate that the alloying effect and the superior electrical conductivity, endow it a great electrocatalytic performance. Such a nanostructured metallic OER electrocatalyst shows a great promise in water splitting.

A novel zinc metal organic frameworks, named ZnL(2,2′-bpy), has been successfully synthesized, serving 3,6-dicarboxylic-9-ethylcarbazole acid (H2L) as ligand. This kind of ZnMOFs was characterized by FI-IR, elemental analysis, SEM, powder X-ray diffraction and single crystal X-ray diffraction to illustrate the structures. TG analysis was applied to investigate the thermostability. Structural analysis demonstrates that ZnMOFs possess triclinic crystal structure which is a 1D chain that occurs distorted-octahedral coordination geometry. Furthermore, the luminescent performance of ZnMOFs is performed and discussed in detail. The results show that ZnMOFs can emit blue luminescence originating, which is assigned to the ligand-to-metal charge transfer (LMCT).

A new diterpenoid alkaloid, named bullatine H (1), along with 10 known diterpenoid alkaloids were isolated from the roots of Aconitum brachypodum Diels (Ranunculaceae). The structure of 1 was elucidated by analysis of its spectroscopic data. It should be noted that compound 1 is the first example with 11, 13-dioxygenated denudatine-type diterpenoid alkaloid isolated from Aconitum brachypodum.

The influence of sintering temperature, carbon content and dispersive agent in ball-milling was investigated on the properties of LiFePO 4 /C prepared using Fe 2 O 3 , NH 4 H 2 PO 4 , Li 2 CO 3 and glucose via solid state reaction. X-ray powder diffraction, scanning electron microscopy and charge–discharge test were applied to the characterization of the LiFePO 4 /C samples synthesized under different conditions. Sintering temperature affects the crystallite/particle size and degree of crystallinity of LiFePO 4 , formation of Fe 2 P and maintenance of carbon in LiFePO 4 /C. Carbon maintenance is favored by low sintering temperature, and 700 °C is optimum for synthesis of LiFePO 4 /C with superior electrochemical performance. A higher carbon content in the range of 4.48%–11.03% results in a better rate capability for LiFePO 4 /C. The dispersive agent used in ball-milling impacts the existent state of carbon in the final product which subsequently determines its charge–discharge behavior. The sample prepared at 700 °C by using acetone as the dispersive agent in ball-milling exhibits an excellent rate capability and capacity retention without any fade at 0.1 C , 1 C and 2 C , with corresponding average discharge capacities of 153.8, 128.3 and 121.0 mA·h·g − 1 , respectively, in the first 50 cycles.

The anoxic decomposition and influence of carbon precursors on the properties of LiFePO4/C prepared by using Fe2O3 were investigated. X-ray powder diffractometry, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and carbon content and charge–discharge tests were applied to the characterization of the as-synthesized cathodes. Partial carbon is lost in the anaerobic decomposition of organic precursors and a high hydrogen content leads to a high residual carbon rate. Pyromellitic anhydride and citric acid participate in reactions before and in ball-milling. All the chosen carbon precursors are capable of producing LiFePO4 with high degree of crystallinity and purity. The carbon derived from α-D-glucose, pyromellitic anhydride, soluble starch, citric acid and polyacrylamide has a loose and porous texture in LiFePO4/C which forms conduction on and between LiFePO4 particles. LiFePO4/C prepared by using α-D-glucose, pyromellitic anhydride, citric acid and sucrose exhibits appreciable electrochemical performance. Graphite alone is able to enhance the electrochemical performance of LiFePO4 to a limited extent but incapable of preparing practical cathode.

LiFePO4/C was prepared via solid state reaction and characterized with X-ray powder diffraction and charge–discharge test. As-prepared LiFePO4/C has a triphylite structure and exhibits an excellent rate capability and capacity retention. Electrochemical impedance spectroscopy (EIS) was applied to investigate Li x FePO4/C (0

LiNi 0.8 Co 0.1 Mn 0.1 O 2 cathode was synthesized using transition metal acetates under different synthesis conditions. Simultaneous thermogravimetric–differential scanning calorimetry–derivative thermogravimetric analysis was applied to investigating the mixture of transition metal acetates. X-ray powder diffraction and charge–discharge test were adopted to characterize the as-prepared LiNi 0.8 Co 0.1 Mn 0.1 O 2 . The mixture of transition metal acetates undergoes dehydration and decomposition during heating. All the examined LiNi 0.8 Co 0.1 Mn 0.1 O 2 samples have a layered structure with space group. LiNi 0.8 Co 0.1 Mn 0.1 O 2 samples prepared with different lithium sources under different synthesis conditions exhibit very different charge–discharge performances. The sample synthesized via the procedure of sintering at 800 °C after heating lithium carbonate and transition metal acetates at 550 °C achieves a highest capacity of 200.8 mA·h/g and an average capacity of 188.1 mA·h/g in the first 20 cycles at 0.2 C .

Fenton reaction is widely used for hazardous pollutant degradation. Reducing agents (RAs) have been proven to be efficient in promoting the generation of HO• in Fenton reaction by accelerating the redox cycle of Fe3+/Fe2+. However, the roles of different RAs in Fenton reaction remain unrevealed. In this work, the catalytic activity of three RAs, i.e., hydroxylamine (NH2OH), ascorbic acid (AA) and cysteine (Cys), on the degradation of benzoic acid (BA) and the hydroxyl radical formation in the Fenton-RAs system were investigated. Results show the catalytic performance of RAs in BA degradation by Fenton reaction followed an order of NH2OH > AA > Cys. Compared with the conventional Fenton system, the effective pH range in the Fenton-NH2OH system extended from 3.0 to 5.0, while the optimal pH in the Fenton-AA and Fenton-Cys systems ranged from 3.0 to 4.0. The Fenton-AA system exhibited a two-stage reaction toward BA degradation, which was different from the Fenton-NH2OH and Fenton-Cys systems. Furthermore, the dosing manner of AA was found to be a key factor governing its role in the Fenton-AA system. This observation suggests the different mechanisms behind the enhancement of the three RAs in Fenton system. Different from NH2OH and Cys, AA would inhibit the generation of HO•, especially at the fast stage of degradation process, where Fe3+ has not accumulated yet. In addition, the economic analysis using the electrical energy per order indicates Fenton-NH2OH system was economically feasible with the lowest energy input, compared to Fenton-AA and Fenton-Cys systems. These results are useful to better understand the roles of RAs in Fenton system, and also provide guidance about the selection and dosing manner of suitable RAs in the advanced oxidation processes.

A LiFePO4/C sample was prepared via solid state reaction and characterized with X-ray powder diffraction, scanning electron microscopy and charge–discharge test. Conductive carbon and highly crystallized LiFePO4 were embedded in each other to form the as-prepared LiFePO4/C, which exhibited an excellent rate capability and capacity retention. The LiFePO4/C electrode reaction was investigated by the method of medium scan rate cyclic voltammetry (CV) under temperature variation. The limit values for the CV redox peak potentials of the LiFePO4/C electrode scanned at different rates were obtained by curve fitting. The reversibility of the LiFePO4/C electrode was studied and found to be both scan rate and temperature dependent. A higher temperature led to a higher critical CV scan rate for a reversible LiFePO4/C electrode. In the electrode process, a higher temperature resulted in a smoother Fe3+/Fe2+ redox reaction, better reversibility, lower R cv, smaller charge transfer resistance and higher Li+ ion diffusion coefficient at the cathode of the LiFePO4/C.

The reactions of [Ir(5-NO2-ppy)2(PPh3)Cl] (5-NO2-ppy = 2-phenyl-5-nitropyridyl, PPh3 = triphenylphosphine, 1) with pseudohalides, replacing the weak π donor Cl− with strong σ donors and π acceptors, lead to three new iridium(III) cyclometalated complexes [Ir(5-NO2-ppy)2(PPh3)(L)] (L = NCO−, 2; NCS−, 3; N3−, 4) based on 2-phenylpyridyl (ppy) derivative, PPh3 and different pseudohalogen strong-field ancillary ligands. 2–4 are unambiguously characterized and their crystal structures are also determined by X-ray crystallography. The HOMO–LUMO electronic energy gaps of 1–4 estimated from the cyclic voltammetry measurements are comparable with those calculated from the UV–Vis absorption spectra, which are both in the order of 3 > 1 > 2 > 4. Furthermore, the electrochemical and photophysical properties of 1–4 show that the introduction of the electron-withdrawing nitro group to the pyridyl ring of the ppy backbone narrows the HOMO–LUMO electronic energy gaps, compared with those of corresponding ppy-containing iridium(III) complexes.

Star copolymers of ε-caprolactone and L-lactide (ε-CL/L-LA) were synthesized with different compositions in the presence of pentaerythritol and using stannous octoate as catalyst. The copolymers were characterized by1H NMR spectra analysis and then blown into films in a single-screw extruder. The mechanical properties study show that the copolymers differed widely in their elongation at break and tensile strength according to the ratio of monomers and pentaerythritol in the copolymerization. The tensile strength of the films deriving from extrusion is much higher than that obtained through solvent volatilization.

The poly (lactide-co-trimethylene carbonate) copolymers are prepared by ring opening polymerization and catalyzed by SnOct and their films are prepared by blow molding. The 1HNMR study demonstrates that PLA-PTMC copolymers were successfully obtained and the graft way is A-B model. The water vapor permeability (WVP) of the films decreases with the increasing TMC content due to the formation of denser structure. The mechanical measurement reveals that the tensile strength of blown films has been declined with the increasing TMC content, but the elongation at break is improved and the tensile strength can be satisfied for the requirement of film product. Therefore, the copolymer film will be great prospect in the application of food and beverage packing.

The polyvinylidene fluoride (PVDF)/Fe3+/Cu2+ hollow fiber membranes were prepared via dry-jet wet phase-inversion method to investigate the effects of pore-forming additives on structures and properties of the membranes in this study. Using polyethylene glycol (PEG) (molecular weight: 400, 6,000, and 20,000 Da), polyvinyl pyrrolidone (PVP) K30, and glyceryl alcohol as pore-forming additives respectively, the membranes were fabricated with the dope solutions of PVDF/additive/Fe3+/Cu2+ when the temperatures of bore liquid/water bath were 60/40°C. The structures and properties of the membranes were characterized by microscope, measurement of pure water permeability (PWP), bovine serum albumin (BSA) rejection ratios, dry strength test and measurement of porosity. The results suggested that these membranes were single skinned external-pressure membranes. The resultant membranes with different organic additives were born with large and long finger-like macrovoids from inner surface. PVP K30 and glycery...

A new kind of Fe3+/polyvinylidene fluoride membrane (PVDF)-poly methyl methacrylate (PMMA) asymmetric catalytic membrane was prepared by the blending method. The hydrophilicity and antifouling properties of Fe3+/PVDF catalytic membrane was increased significantly after blended with PMMA. The influence of some factors such as polymer blending ratio, polymer concentration, additives, temperature of coagulation bath on the pure water flux, and BSA retention were discussed. The catalytic activity of Fe3+/PVDF-PMMA catalytic membrane was evaluated by the degradation of refractory dye Orange IV in the presence of H2O2. The results showed that the addition of appropriate PMMA in the preparation of Fe3+/PVDF membrane has greatly decreased the contact angle of the membrane. Fe3+/PVDF-PMMA membrane had better anti-fouling than Fe3+/PVDF membrane. The Fe3+/PVDF-PMMA catalytic membrane’s retention rate decreased and pure water flux increased with the increase of PMMA. When the mass ratio of (PVDF)/(PMMA) was...

The technology of the acidification is adopted to prepare arsenic trioxide (As2O3). With a concentration of 98% of concentrated sulfuric acid and Orpiment made into a certain ratio of the slurry suspension. Arsenic trioxide’s content is 99.94%, extraction yield can reach to 98.92%. The optimal conditions is reaction temperature at 120°Cand the reaction time in 2.5 h; the slurry ratio is less than 1/6 and particle size is less than 0.080 mm.

With the development of industrial production and the improvement people's living standards, all kinds of discharged wastewater cause serious pollution for nitrogen and phosphorus.In this study, the water of Dianchi lake was treated by Ultrasonic – flocculation. The results show ultrasound-flocculation sedimentation is better than only flocculation sedimentation in removing the total phosphorus, total nitrogen and reducing COD, BOD and turbidity respectively increased 16.19%, 12.71%, 9.1%, 20%, 18.3%.

Phosphogypsum is the gypsum as a byproduct of the processing of phosphate ore into fertilizer with sulfuric acid. It’s main components is CaSO4. Circulating fluidized bed(CFB) is the best reactor. In this paper the characteristics of phosphogypsum decomposition were analyzed via CFB reaction in cold test. And applied quantity of wind and bed material influenced bed pressure and the quantity of solides and solids concentration.

LiMn2O4 cathode materials were successfully prepared by solid-state combustion synthesis with the lithium carbonate and the manganese carbonate as raw materials and the citric acid as fuel. The effect of citric acid on composition, microstructure and electrochemical properties of LiMn2O4 cathode materials was investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), cyclic voltammetry (CV) and galvanostatic charge-discharge test. The results indicated that a pure phase of LiMn2O4 was prepared at the product with 5 wt% citric acid. However, an impure phase of Mn3O4 was found at other products. The crystal size distribution was more uniform at the higher content of citric acid. The products with 5 wt% and 10 wt% citric acid, the cubic structure morphologies of which were more prominent, and the capacities of which were higher than that of bare LiMn2O4 product. Their initial discharge specific capacities were 119.6 mAh•g-1 and 114.0 mAh•g-1, and their capacity retention ratios after 40 cycles were 85.0% and 87.7%, respectively.

The zinc coating was immersed into a rare-earth conversion coating treatment liquid, with Ce(NO3)3•6H2O as the main salt and 30% H2O2 as the oxidizing agent. A Ce-H2O series potential-pH diagram and a Zn-H2O series potential-pH diagram were then established by calculating the maximum pH value obtainable on the interface. Therefore, the cerium conversion coating was deduced to be composed of ZnO, CeO2, Ce2O3, Ce(OH)3, and Ce(OH)4, In addition, XPS and XRD was used to analyze the appearance and phase of the cerium-based conversion coating in terms of the rare-earth conversion coating obtained in the experiment. The results reveal that the cerium-based conversion coating is the compound coating mainly consists of ZnO, CeO2, Ce2O3, Ce(OH)3 and Ce(OH)4, which is in line with the theoretical analysis.

This paper aims to study the impact of cerium on the corrosion resistance of zinc coating in 5% NaCl solution. Based on the immersing experiment, electrochemistry was used to measure the electrochemical parameters when comparing the zinc coating’s corrosion resistance with that of zinc coating with an additional cerium conversion coating. SEM and XRD were adopted to analyze the appearance and phases of corrosion products of this cerium conversion coating, and to probe the impact of cerium on the corrosion behavior of zinc coating in Cl- environment. The results showed that cerium conversion coating formed on the zinc coating effectively increased the zinc’s corrosion resistance. By contrast, models of conversion coating with lower cerium content poorly protected the substrate, resulting in easy erosion of the zinc coating in Cl- environment.

Immersion precipitation is one of the commonly used methods in preparing polyvinylidene fluoride membrane (PVDF) membrane. Using this method, the membrane structure is easily controlled and the operation is very simple. This paper summarized the mechanism and preparation methods of PVDF as well as researching the effects of membrane-forming factors such as ingredient of solvents and non-solvents, temperature and additives etc. on the structure and function of PVDF membrane. Applying modification on PVDF membrane can improve its hydrophilicity and anti-fouling properties, of which blending modification is expected to be a hotspot of study in future. Adding catalytic agent into PVDF can generate catalytic membrane, which offers a researching direction for preparing multi-functional PVDF membrane. Finally, brief comments are made on the improvement of membrane pore structure and problem of singleness of blending materials.

A new heterogeneous catalyst Fe-Mn/GAC (iron and manganese were loaded into activated carbon particles) was prepared, which had a better catalytic reactivity to decompose H2O2 compared with Fe/GAC and Mn/GAC. The removal rate of Orange IV increased more than 10% with this catalyst compared with Fe/GAC and Mn/GAC. The effect of the initial concentration of H2O2, the initial dye concentration, the initial catalyst concentration, the initial pH and temperature on the reaction rate constant were also studied. The activated energy for Fe-Mn/GAC catalyzed oxidation of the dye was determined to be 66.16KJ/mol. Reuse of catalyst did not decrease the removal rate of Orange IV. The tert-butanol experiment indicated that there were not only hydroxyl radicals but also other active species in the system.

A new heterogeneous Fenton-like catalyst of Fe/S/GAC was prepared by granular activated carbon (GAC) soaked in solution of (NH4)2S2O8 and Fe(NO3)3. The effect of the concentration of (NH4)2S2O8 , Fe(NO3)3, drying temperature and different catalysts on the catalytic reactivity of catalyst was discussed. The removal rate of Orange IV was used to express the catalytic reactivity of the catalyst. The prepared catalysts were characterized by X-ray diffraction (XRD), specific surface area (BET) and scanning electron microscopy (SEM). The removal rate of Orange IV followed second-order kinetics. The catalyst of Fe/S/GAC has higher catalytic activity than that of Fe/GAC.

Effect of calcination temperature on spinel LiMn2O4 by molten-salt flameless combustion synthesis using the lithium acetate (lithium nitrate), manganese acetate (manganese nitrate) as raw materials was studied. The structural characterization and morphology of the powder were measured by X-ray diffraction and Scanning electron microscopy. The results indicated that the main phase was LiMn2O4, which could be obtained at 400-700 °C. The product crystallinity and particle size increased with increasing calcination temperature, but the capacity and cyclic stability decreased. When LiMn2O4 was calcinated at 400 °C and 500°C, the initial specific capacity at 0.1C rate was 104.2 and 101.5 mAh·g-1, respectively. After 30 cycles, the discharge capacity retention rate was 80.4 % and 83.5 %, respectively. The performance was the worst when LiMn2O4 was calcinated at 700°C, when the initial specific capacity was only 81.9 mAh·g-1.

Effect of nitric acid and the burning time on the liquid combustion synthesis of spinel LiMn2O4 has been studied, using lithium nitrite and Manganese acetate as raw a material. The results show that the main phases are all LiMn2O4, which can be obtained at 400-600 oC. Before modified, the impurity is Mn3O4 or Mn2O3. After modified, the impurity is only Mn3O4. The aggregation obviously reduced after adding nitric acid, it is indicated that the crystalline increased. With the increasing temperatures, the modified particle size was increased and the aggregation reduced. The initial discharge capacity and cycle stability improved at some extent too. Its first discharge capacity was 104.6, 112.8 and 117.7mAh/g synthesized at 400, 500, 600 oC, respectively, and the 30th capacity retention rate were 84.89%, 80.67% and 73.24%.

The influences of space velocity, temperature and copper content in Cu-MCM41 catalysts with high copper content up to 26.1wt.% on the catalytic activity in NO reduction by CO were investigated. Results indicated 1) the prepared materials exhibited excellent activity for NO+CO reaction, 2) the catalytic activities increased with the copper contents and NO can be fully converted to N2 for the catalyst containing 26.1wt.% Cu with the space velocity of 30,000ml•g-1•h-1 at 673K to 823K, 3) catalytic activities of the original catalysts with the temperature were volcano-type curves, however, it increased straightly with temperature over the catalysts after reacting at 723K for 1h, which might be attributed to the different active sites and different catalytic mechanisms of the catalysts at lower and higher temperature, 4) the catalytic activity did not decline after reacting at 723K for 20 h in a reactant gas mixture of 33,000 ppm NO and 66,000 ppm CO.

Solid super acid (S2O82-/FexOy-CuOx) was prepared and used as a heterogeneous Fenton-like catalyst to decompose H2O2for the degradation of refractory dye Orange IV in water. The factors that affected the degradation of Orange IV were discussed in this heterogeneous Fenton-like system. The catalytic activity of S2O82-/FexOy-CuOxwas evaluated by the degradation of Orange IV and the decomposition of H2O2. The results show that the catalyst S2O82-/FexOy-CuOxhas a good catalytic activity. The reaction follows pseudo-first-order kinetics; the reaction rate constant has a good relationship with the concentration of H2O2. The degradation rate of Orange IV and the decomposition rate of H2O2increase with the increase of temperature and the dosage of catalyst whereas it decreases with the increase of the initial concentration of Orange IV and the initial pH.

A new Fenton-like catalyst was prepared to degrade Orange IV in water by catalytic decomposition of H2O2. The optimal preparation conditions were discussed. The catalytic activity of catalyst was evaluated by the degradation of Orange IV and the decomposition of H2O2. The results show that solid super acid (S2O82-/FexOy) soaked in (NH4)2S2O8 is the most effective catalyst among the synthesized iron oxides soaked in other oxidants. The optimal conditions for solid super acid preparation are calcined at 500 for 2 h in the air.

A new kind of PVDF/Fe3+/Cu2+ catalytic membrane was prepared and used as a heterogeneous Fenton-like catalyst to degrade Orange IV in the presence of H2O2. The effect of initial concentration of H2O2 and Orange IV, initial pH, reaction temperature and catalyst dosage on the reaction rate was studied. The results show that the higher the concentration of H2O2, the faster the reaction rate is. The reaction rate increased with the increase of temperature with the activation energy 30.18KJ•mol-1. The PVDF/Fe3+/Cu2+ catalytic membrane can effectively decolorize Orange IV in the pH range of 3.1-5.3. The decolorization rate of Orange IV decreased with the increase of initial concentration of Orange IV. The decolorization rate of Orange IV increased with the increase of dosage of catalyst. The reactive intermediates for this reaction is HO• based on t-butanol experiments.

Solid super acid(S2O82-/FexOy-CuOx)was prepared and used as a Fenton-like catalyst to decompose H2O2 for the removal of orgnanic pollutants in water. The catalytic activity of S2O82-/FexOy-CuOx was evaluated by the degradation of organic pollutants and the decomposition of H2O2. The results show that the catalytic activity of S2O82-/FexOy-CuOx to decompose H2O2 is higher than that of S2O82-/FexOy. The reason for this may be due to the dissolved of Fe2+ from the S2O82-/FexOy-CuOx, and the concentration of dissolved of Fe2+ is proportional to the concentration of organic pollutants in water. The degradation rate of phenol by the catalyst of S2O82-/FexOy-CuOx is obviously higher than that by the catalyst of Fe2+ ion under the same conditions. BET measurements show that the surface area of S2O82-/FexOy-CuOx is larger than that of S2O82-/FexOy.

A new heterogeneous PVDF/Fe3+-TiO2 catalytic membrane is prepared by sol-gel method, which had a well catalytic activity to decompose H2O2. The effect of initial pH, e initial concentration of H2O2 and Orange IV, temperature, and membrane area on the reaction rate is discussed. The PVDF/Fe3+-TiO2 catalytic membrane can effectively decolorize Orange IV in the pH range of 3.0-5.0. The optimal concentration of H2O2 is 15mmol/L. The reaction rate constant is proportional to the initial concentrations of Orange IV. The higher the temperature, the faster the reaction rate is, this reaction follows pseudo-first-order kinetics with activation energy of 1.54kJ/mol. Reuse of catalyst did not decrease the removal rate of Orange IV. The experiments of t-butanol, EDTA and XPS measurement showed that •OH, the electron hole and the ferryl are all the reactive species in the degradation of Orange IV.

Electrodeposited Zn and Zn-Fe alloy have been applied widely to protect steel from corrosion, but the property of coating still needs to be improved. In this paper, Zn-Fe-SiO2 composite coatings are electrodeposited from Zn-Fe alloy electrolyte containing SiO2 particles. Zinc based coatings with Fe% >1%(mass) are deposited from sulfate bath, and coatings with Fe%