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• WO 3 /MoO 3 /g-C 3 N 4 and Serratia marcescens catalyze the production of acetate in photo-assisted MES. • Appreciable high production of acetate and coulombic efficiency are achieved. • WO 3 /MoO 3 and g-C 3 N 4 interact in a Z-scheme mechanism to enhanced electrons-holes separation. • Photo-induced electrons on the conduction band of semiconductor enhance H 2 production. • Photo-generated holes favor higher current and thus higher acetate production. The efficient production of acetate from HCO 3 − is demonstrated in a photo-assisted microbial electrosynthesis system (MES) incorporating a WO 3 /MoO 3 /g-C 3 N 4 heterojunction photo-assisted biocathode supporting Serratia marcescens Q1 electrotroph. The WO 3 /MoO 3 /g-C 3 N 4 structured electrode consisting of a layer of g-C 3 N 4 coated on graphite felt decorated with W/Mo oxides nanoparticles exhibited stable photocurrents, 4.8 times higher than the g-C 3 N 4 electrode and acetate production of 3.12 ± 0.20 mM/d with a CE acetate of 73 ± 4 % and current of 2.5 ± 0.3 A/m2. Photo-induced electrons on the conduction bands of WO 3 /MoO 3 /g-C 3 N 4 favoured hydrogen evolution, which was metabolized by S. marcescens with HCO 3 − to acetate, while the holes were refilled by the electrons travelling from the anode. Such mechanism reduced the interfacial resistances creating a supplementary driving force leading to higher acetate production. The biocompatible components of WO 3 /MoO 3 /g-C 3 N 4 synergistically couple light-harvesting and further catalyze S. marcescens to acetate from HCO 3 −, providing a feasible strategy for achieving sustainable high rates of acetate production. [ABSTRACT FROM AUTHOR]

• Intensified mineralization of metronidazole in photo-assisted MFCs with Mo/W cathodes. • Optimal Mo/W loadings and ratios for metronidazole degradation and mineralization. • Anaerobic conditions favors the reductive degradation of metronidazole. • Aerobic conditions favors the mineralization of metronidazole in Fenton-MFCs. • Combined photo and Fenton processes accelerate the mineralization of metronidazole in MFCs. A novel strategy to intensify the degradation and mineralization of the antibiotic drug metronidazole (MNZ) in water with simultaneous production of renewable electrical energy was achieved in photo-assisted microbial fuel cells (MFCs). In this system Mo and W catalytic species immobilized onto a graphite felt cathode intensified the cathodic reduction of MNZ under anaerobic conditions and the oxidation of MNZ under aerobic conditions. The aerobic oxidation process was further accelerated in the presence of Fe(III), realizing a combined photo-assisted MFCs and Fenton-MFCs process. The highest rates of MNZ degradation (94.5 ± 1.4%; 75.6 ± 1.1 mg/L/h) and mineralization (89.5 ± 1.1%; 71.6 ± 0.9 mg/L/h), and power production (251 mW/m2; 0.015 kWh/m3; 0.22 kWh/kg COD) were achieved at a Mo/W loading of 0.18 mg/cm2 with a Mo/W ratio of 0.17:1.0, in the presence of 10 mg/L of Fe(III) and at an incident photon flux of 23.3 mW/cm2. Photo-generated holes were directly involved into the oxidation of MNZ under anaerobic conditions. Conversely, under aerobic conditions, the photo-generated electrons favored the production of O 2 − over OH, while in the presence of Fe(III), OH was predominant over O 2 −, explaining the intensification of the MNZ mineralization observed. This study demonstrates an alternative and environmentally benign approach for the intensification of the removal of the antibiotic MNZ in water and possibly other contaminants of emerging concern by combining photo-assisted MFCs and Fenton-MFCs in a single process with simultaneous production of renewable electrical energy. [ABSTRACT FROM AUTHOR]

Abstract: Luminescent lanthanide complexes (Eu3+ and Tb3+) of a new tripod polyaromatic acid ligand, H3TCM 2,4,6-tris[(2′-carboxyphenoxy)methyl]-1,3,5-trimethylbenzene, have been prepared. The complex of Eu3+ was self-assembled in DMF and a novel binuclear box-like structure was obtained. [Copyright &y& Elsevier]

Graptolite-rich shale is the main layer of shale gas resources in the southern marine sedimentary basin. Recently, shale gas resources were discovered in the Ordovician marine graptolite-rich strata in the Ordos Basin. The graptolite shale in the study area is different from the marine graptolite shale in the Yangtze plate in southern China, and further exploration is needed. This paper presents core samples of the graptolite-rich shale of the Pingliang Formation in the southwest Ordos Basin as research objects. The graptolite genus and graptolite shale characteristics were studied using core observation, electron microscopy, scanning electron microscopy, and geochemical analysis. We determined the role of the sedimentary environment and thermal maturation of graptolite shale in hydrocarbon formation and explored the possibility of hydrocarbon generation. Many graptolite epidermises provide buried organic matter. The quiet sea and low-energy marine environment create favorable conditions for preserving organic matter. The tectonic process resulted in the evolution stage in the oil generation window. Different types of pores formed the spaces of hydrocarbons. Therefore, the shale of the Pingliang Formation has shale oil exploration potential, which complements the shale gas in the northwestern margin of the basin, and provides new venues for shale oil and gas exploration in northern China. [ABSTRACT FROM AUTHOR]

A new bipod polyaromatic acid ligand H 2bcm (H 2bcm = {2, 4-bis [(2′-carboxyphenoxy) methyl]-1,3,5-trimethylbenzene}) is prepared and its two novel binuclear coordination compounds, [Cu 2(bcm) 2(CH 3OH) 2]·2CH 3OH ( 1) and [Cu 2(bcm) 2(CH 3CH 2OH) 2]·2CH 3CH 2OH ( 2), have been synthesized with copper acetate and H 2bcm ligand in methanol solvent and ethanol solvent respectively, and characterized by the element analysis, IR, TGA and single crystal X-ray diffraction. The results of structural analysis indicate that 1 crystallizes in the triclinic system with space group P1, while 2 crystallizes in the monoclinic system with space group P2 1/c. Furthermore, 1 adopts μ2-COO − and syn– syn coordination mode with Cu (II)···Cu (II) separation of 2.5868(11) Å and forms 1D zigzag chain structure by O···O interactions. The coordination of 2 is similar to that of 1 except that ethanol molecules are coordinated instead of methanol molecules with Cu (II)···Cu (II) separation of 2.5973(13) Å. Two-dimensional network structures of 1 and 2 are formed through π–π interactions. Graphical Abstract: A new bipod polyaromatic acid ligand H 2bcm (H 2bcm= {2, 4-bis [(2′-carboxyphenoxy)methyl]-1,3,5-trimethylbenzene}) is prepared and its two novel binuclear coordination compounds, [Cu 2(bcm) 2(CH 3OH) 2]·2CH 3OH ( 1) and [Cu 2(bcm) 2(CH 3CH 2OH) 2]·2CH 3CH 2OH ( 2), have been synthesized with copper acetate and H 2bcm ligand in methanol solvent and ethanol solvent respectively, and characterized through single-crystal X-ray diffraction. Compound 1 crystallized in the space group P1, while 2 crystallizes in the monoclinic system with space group P2 1/c. Since the only difference in the synthetic condition between complexes 1 and 2 is that of the reaction solvent, resulting in the structure of complex 1 being significantly distinct from that of complex 2. It is clear that reaction solvent plays a key role in controlling the structure of the complexes.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

• WO 3 /MoO 3 /g-C 3 N 4 and Serratia marcescens catalyze Cr(VI) removal and acetate production. • Photo-generated electrons increase the rates of HCO 3 − and Cr(VI) reductions. • Photo-generated holes increase the circuital current. • Higher circuital currents improve Cr(VI) removal and acetate production. The removal of the hazardous heavy metal Cr(VI) in water and the simultaneous production of acetate from the reduction of inorganic carbon (HCO 3 −) is demonstrated in a photo-assisted microbial electrosynthesis (MES) system incorporating WO 3 /MoO 3 /g-C 3 N 4 Z-scheme heterojunctions and Serratia marcescens Q1 electrotroph cathode. The rates of acetate production (6.1 ± 0.3 mg/L/h) and Cr(VI) removal (4.5 ± 0.1 mg/L/h) recorded at a circuital current of 2.8 ± 0.1 A/m2 were 2.4-fold (acetate production), 1.7-time (Cr(VI) removal) and 1.6-fold (circuital current) of those in the controls recorded in the absence of WO 3 /MoO 3 /g-C 3 N 4 , and 1.6-fold (acetate production) and 1.8-time (circuital current) of those in the absence of both Cr(VI) and WO 3 /MoO 3 /g-C 3 N 4. Photogenerated WO 3 /MoO 3 /g-C 3 N 4 conduction bands electrons favored both direct or indirect (via S. marcescens) reductions of Cr(VI) and H+, with the latter producing H 2 which was further metabolized by S. marcescens with HCO 3 − to yield acetate. The higher circuital current drawn under photoirradiation conditions refilled the photo-generated valence band holes in the semiconductor and provided the driving force for the reduction reactions. This study provides an alternative and feasible approach for achieving complete removal of toxic heavy metal from water and industrial waters with simultaneous conversion of inorganic carbon to key block chemicals. [ABSTRACT FROM AUTHOR]

Efficientdelivery of therapeutic agents with nanocarriers intothe nucleus to achieve high therapeutic efficiency is still a majorchallenge for cancer therapy due to mucosal barriers, nonspecificuptake, and intracellular drug resistance. In this study, we developa dual-responsive polymer micelle system with sheddable polyethylenimine(PEI) shells for actively targeted drug delivery. This system exhibitsan ultrasensitive negative-to-positive charge reversal in responseto the extracellular pH value, resulting in greatly enhanced uptakeby cancer cells via electrostatic interaction. Moreover, the activetargeting ability can further promote the selective uptake of thenanocarriers in the cancer cell. Once the micelles escape from thelysosomes, the disulfide linkages can be cleaved by GSH in the cytoplasm,and in turn the hydrophilic PEI shell is deshielded, leading to therapid release of the encapsulated agent into the nuclei. The antitumoractivity in 4T1 tumor-bearing mice reveals that this novel systempossesses a long blood circulation due to the originally negativelycharged surface and can significantly promote the cell internalizationand intracellular drug release, thus leading to a high therapeuticefficacy against resistant tumors and fewer side effects to normaltissues. [ABSTRACT FROM AUTHOR]

The total organic carbon of carbonate sediments includes a 5%–45% contribution from acid-soluble organic matter, particularly carboxylic acid salts. However, there is little information available on hydrocarbon generation from carboxylic acid salts. The objectives of this study were to investigate the extent and timing of hydrocarbon generation from calcium stearate. Thus, gold-tube nonhydrous pyrolysis experiments of calcium stearate were conducted from 250 to 600 °C at 50 MPa. Infrared spectroscopy and δ13C testing were also performed on solid pyrolysate and gaseous products, respectively, to trace changes of functional groups and stable carbon isotopes. Pyrolysis of calcium stearate produced hydrocarbons, CO 2 , CaO, CaCO 3 , coke, and other inorganic compounds of low molecular weight. A Van Krevelen diagram indicated that calcium stearate falls in the same region as hydrogen-rich type I kerogen. The maximum yield of methane generated from calcium stearate was as high as that from North Sea oil. Hydrocarbon generation from calcium stearate was related to cracking of the alkyl moiety and similar to that occurring in pyrolysis of n- C 18. As a consequence of kinetic carbon isotope fractionation, with increasing temperature CO 2 becomes enriched in 13C and CaCO 3 becomes enriched in 12C. Notably, CaCO 3 with very low δ13C values is probably an effective proxy indicating hydrocarbon generation from carboxylic acid salts, if no other CaCO 3 is produced via thermochemical sulphate reduction processes. The optimized kinetic parameters demonstrate that calcium stearate had higher methane generation activation energies than those of n -C 18 and type I kerogen. Hence, methane generation from calcium stearate is delayed when extrapolated to geological conditions. This retarded methane generation illustrates the vital role of carboxylic acid salts in the generation of deep oil and gas. Future research should concern the abundance of carboxylic acid salts in carbonate formations and the depositional environments that facilitate the formation of carboxylic acid salts. • Closed gold-tube pyrolysis of calcium stearate was conducted. • Calcium stearate had gas potential as high as crude oil. • Negative δ13C CaCO3 may indicate hydrocarbon generation from carboxylic acid salts. • Methane generation from calcium stearate was behind that of n- C 18. [ABSTRACT FROM AUTHOR]