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[Display omitted] The photocatalytic performance of ceria-based materials can be tuned by adjusting the surface structures with decorating the transition-metal, which are considered as the important active sites. Herein, cuprous oxide-metallic copper composite - doped ceria nanorods were assembled through a simple hydrothermal reduction method. The photocatalytic ammonia synthesis rates exhibit an inverted "V-shaped" trend with increasing Cu0/Cu x O mole ratio. The best ammonia production rate, approximately 900 or 521 µmol·g cal −1·h−1 under full-spectra or visible light, can be achieved when the Cu0/Cu x O ratio is approximately 0.16, and this value is 8 times greater than that of the original sample. The absorption edge of the as-prepared samples shifted towards visible wavelengths, and they also had appropriate ammonia synthesis levels. This research provides a strategy for designing noble metal-free photocatalysts through introducing the metal/metallic oxide composites to the catalysts. [ABSTRACT FROM AUTHOR]

Mitochondrial DNA is typically passed to offspring through maternal inheritance. However, in mussels, two kinds of mitochondrial DNA exist: F and M type, which are referred to as doubly uniparental inheritance (DUI). Studies have shown that DUI may be related to gender determination. In this study, we obtained the first complete F-type mitochondrial genome of Lamprotula scripta and Lamprotula caveata which were 16,250 bp and 16,641 bp in length, respectively, and had 13 protein coding genes (PCGs), 22 transfer RNAs, 2 ribosomal RNAs and 27 non-coding (NC) regions. The largest NC region of L. scripta was 639 bp and located between ND5 and tRNA Gln . The largest NC of L. caveata was 1046 bp and also located between ND5 and tRNA Gln . The overall AT content of L. scripta and L. caveata was 58.95% and 58.66%, respectively, which were lower than Lamprotula leai , Lamprotula gottschei and Lamprotula tortuosa. We next compared F and M mitochondrial genomic data on freshwater mussels and established a phylogenetic tree based on amino acid sequences of 13 PCGs and COII gene. Our results showed that F- and M-type mitochondria were significantly separated into two branches, and the basic structure of phylogenetic trees were divided into four distinct groups: Unioninae, Anodontini, Gonideinae and Ambleminae. Relatives of Gonideinae and Ambleminae were more closely related than Unioninae and Anodontini, indicating significant differences in mtDNA between the two mitogenome types. Moreover, we revealed that L. scripta and L. caveata are closely relatives, suggesting that they are both subordinates of the Gonideinae subfamily. Consequently, we speculate that the formation of DUI hinders their disappearance, which provides a basis for further studies into the mechanisms and genetic diversities of DUI formation. • We obtained the first complete F-type mitochondrial genome of Lamprotula scripta and Lamprotula caveata. • Phylogenetic trees showed significant differences in mtDNA between F-type and M-type mitogenome. • L. scripta and L. caveata were closely relatives. • Results provided a basis for further studies on the mechanisms and genetic diversities of DUI formation. [ABSTRACT FROM AUTHOR]

Two types of α-Fe 2 O 3 nanostructures were synthesized under hydrothermal conditions in the presence of glycerol. Urchin-like α-Fe 2 O 3 with limited (001) plane exposure and flower-like α-Fe 2 O 3 with a high degree of (001) plane exposure were used to modify the surfaces of screen-printed electrodes (SPEs), which were then employed in electrochemical Cr(VI) detection. Linear sweep voltammetric results indicate that the high exposure of the (001) plane could result in a high current response toward Cr(VI) reduction due to the high adsorption capacity induced by doubly and triply coordinated hydroxyl groups on the surface of α-Fe 2 O 3. The modified SPE had a linear response to Cr(VI) in the 5–3000 μg/L concentration range with a detection limit of 1.17 μg/L. Unlabelled Image • α-Fe 2 O 3 with different degree of (001) plane exposure were synthesized under hydrothermal condition • Electrochemical Cr(VI) detection was achieved at α-Fe 2 O 3 modified screen printed electrode • High exposure of the (001) plane could result in a high current response toward Cr(VI) reduction • Sensor exhibits a linear response to Cr(VI) in the 5-3000 μg/L concentration range with a detection limit of 1.17 μg/L [ABSTRACT FROM AUTHOR]

[Display omitted] • A new conductive MOF with wheel-shaped metallomacrocycle subunits was synthesized. • The new MOF maintains the structure of the insulator MOF, but becomes semiconductor. • The performance of the new MOF supercapacitor has been greatly improved. The poor conductivities of metal–organic frameworks (MOFs) hinder their direct application as supercapacitor electrode materials. Here, a conductive MOF, MWM-1 (Co/2Ni) ([Co(III) 3 Ni(III) 3 Co(II) 2 Ni(II) 2 (mba) 12 (Hdtba) 2 (H 2 O) 8 ] n , Hdtba = 2,2́-dithiodibenzoic acid monovalent anion, mba = 2-mercaptobenzoic acid divalent anion), with wheel-shaped metallomacrocyclic subunits, is synthesised using inexpensive H 2 mba as the ligand. Unlike that of two-dimensional conductive MOFs produced using expensive conductive ligands, the conductivity of MWM-1 (Co/2Ni) originates from the partial replacement of Co(III)/Co(II) ions with Ni(III)/Ni(II) ions in the original molecular metallomacrocyclic backbone. The single-crystal structure of MWM-1 (Co/2Ni) reveals that Ni incorporation does not alter the overall molecular structure of the non-conductive MWM-1 (Co) ([Co(III) 3 Co(II) 2 (mba) 6 (Hdtba)(H 2 O) 4 ] n) precursor. Studies on the magnetic and conductive properties of MWM-1 (Co/2Ni) and MWM-1 (Co) indicate that Ni doping of MWM-1 (Co) significantly improves its conductivity and, thus, its performance as an electrode material for supercapacitors. This study provides a novel strategy for constructing conductive MOFs, advancing the applicability of MOF materials in energy storage. [ABSTRACT FROM AUTHOR]

To obtain various Ni/Mn orderings, we use a low-temperature synthesized method to modulate the Ni/Mn ordering of the ferromagnetic-ferroelastic La2NiMnO6 compound, and the Ni/Mn ordering is estimated by the low-temperature saturation magnetism. The microstructures, crystal structures and magnetic properties are investigated, and the Landau theory are used to describe the form and magnitude of the coupling effects between Ni/Mn ordering and magnetic order parameters. It is predicted that the Ni/Mn ordering would be a strong coupling effect with the Curie transition temperatures if the La2NiMnO6 sample stoichiometry is close. [ABSTRACT FROM AUTHOR]

The widespread application of zinc oxide nanoparticles (nano-ZnO) has received increasing attention because of their potential risks to human health and the environment. This review summarizes the relationship between the toxic effects and physicochemical properties of nano-ZnO and the underlying toxicity mechanisms of nano-ZnO. This study presents the possible human health hazards posed by nano-ZnO exposure and the biotoxicity to bacteria, algae, higher plants, aquatic animals, terrestrial invertebrates and vertebrates in vitro and in vivo. The advances in research on the ecotoxicity of nano-ZnO and the potential risks to human health are discussed. Finally, the current research deficiencies in this area are identified, and recommendations for future research are proposed. [ABSTRACT FROM AUTHOR]

In this work, we report the attractive magnetic properties of La1-xCaxMnO3 manganites with x = 0.2 (LCMO-2) and x = 0.5 (LCMO-5). X-ray diffraction (XRD) measurements show that the prepared samples are single phase and they crystallize in the orthorhombic structure with Pnma space group. Scanning electron microscope (SEM) measurements reveal that the particles of samples are homogeneous and possess the diameter of several microns. Magnetization versus temperature measurements show paramagnetic (PM) to ferromagnetic (FM) transition at TC ≈ 200 K for LCMO-2 and at TC ≈ 250 K for LCMO-5. Below TC, FM nature is observed in LCMO-2. However, LCMO-5 displays the complex magnetic phase transition. Below TC, LCMO-5 shows a FM to charge-ordered antiferromagnetic (COAFM) transition at CO temperature TCO and a novel, unexpected FM phase transition at characteristic temperature T* (near 35 K). The FM and COAFM phases coexist in LCMO-5, and the competition of FM and AFM phases lead to the unexpected FM transition at T*. Furthermore, the inverse of susceptibility versus temperature measurements confirm the similar results. Magnetic hysteresis loop measurements suggest the typical FM feature of LCMO-2. However, LCMO-5 exhibits the hysteresis loops with butterfly-type structure at 100 and 150 K, suggesting the presence of COAFM phase. These attractive magnetic properties are explained by the existence of COAFM phase and the competition between FM and COAFM phases. [ABSTRACT FROM AUTHOR]

Mercury ions can significantly affect the organism and environment even at a very low concentration. Thus, great efforts have been devoted to developing high sensitive electrochemical sensors, especially the one that not only detect the mercury ions but also effective sensitive to thymine-Hg2+-thymine in aqueous solution. Metal-organic-frameworks (MOFs) possess hollow nature and are easy for grafting functional groups, however, there is still no attempts for working as electrochemical sensors in detecting mercury ions. Herein, we report a novel type sensor of Zr(IV)-based MOFs with specifically attached thioether side groups allowing mercury ions to be easily adsorbed and detected. The Zr(IV)-involved MOFs show strong binding to mercury ions compared with the bare MOFs, as confirmed by both experiment measurements and theoretical calculations. The as-prepared senor is sensitive ranging from 0.01 nM to 3 μM with detection limitation of 7.3 fM, which is better than most of T-Hg2+-T- and enzyme-based sensors reported so far. The high sensitivity could be due to the straightforward adsorption pathway and the biomolecule exclusion nature of the Zr(IV)-involved MOFs sensor. We anticipate that our findings could pave the way for MOFs-based sensor exploration towards its commercial applications. Image 1 • Our new conceptual approach (sulfur function of MOF) enables us to fabricate an efficient electrochemical detection of mercury ions. • The stripping peak current varied linearly (S–Zr-MOF) with the mercury ion concentration in the range of 0.01 nM–3 μM. [ABSTRACT FROM AUTHOR]

A microporous metal-organic framework (MOF) with ttd-type topology, [Mn 2 (FDDI)](DMF) 5.5 (H 2 O) 4.5 (Mn-MOF ; H 4 FDDI = 5,5'-(9H-fluorene-2,7-diyl)-diisophthalic acid (DMF = C 3 H 7 NO) was solvothermal obtained and characterized. Mn-MOF contains three different channels that show excellent removal of low concentration of crystal violet as compared with methyl orange and methylene blue from the aqueous solution at 298 K. A novel microporous metal-organic framework (MOF) with ttd-type topology has been obtained that exhibited excellent removal of low concentration of crystal violet (CV+) as compared with methyl orange (MO−) and methylene blue (MB+) from the aqueous solution at room temperature. Image 1 • A novel microporous MOF Mn-MOF was synthesized and structurally characterized. • Mn-MOF has three different types of channels and exhibits ttd-type topology. • Mn-MOF shows excellent removal of low concentration of crystal violet (CV+). [ABSTRACT FROM AUTHOR]

An anionic multifunctional porous metal organic framework (MOF), [Cu2THBA(H2O)2]·(C3H7NO)12·(H2O)10 (1) (H4THBA = p‐terphenyl‐3,2′′,3′′,5,5′′,5′′′‐ hexcarboxylic acid) with NbO‐type topology was synthesized and characterized. Due to multiple functional sites and suitable pore size, the desolvated compound 1a exhibits high separation selectivity for C2H2/CO2 of 30 and C2H2/CH4 of 131 at 1 kPa at room temperature. Compound 1 can also efficiently and completely separate methylene blue (MB+) molecules of low concentrations from aqueous solution in 12 h. [ABSTRACT FROM AUTHOR]

Abstract Silver nanoparticles (Ag-NPs) are increasingly being applied in many consumer products due to their unique properties. Widespread use of Ag-NPs leads to an increasing human exposure to Ag-NPs in many different pathways. This review summarized the toxicity mechanisms of Ag-NPs based on various environmentally relevant test species, such as bacteria, cells, plants, aquatic animals and mammals, in both in vitro and in vivo experiments. Nanoparticles were usually exposed to combination chemicals but to single chemicals in the environment and thereby exert combined toxicities to the organisms. Therefore, the joint effects of nanomaterials and their co-existing characteristics were also discussed. The current knowledge gaps and safe product designs of Ag-NPs have been discussed in detail. The limited and existing data implied that understanding the toxicity mechanisms is crucial to the future research development of nanomaterials. Highlights • Presented the possible human health hazards related to Ag-NPs exposure. • Identified the current research deficiencies in this area. • Summarized the underlying toxicity mechanisms. • Summarized the compound toxicity of NPs. [ABSTRACT FROM AUTHOR]

Abstract Perfluorooctane sulfonate (PFOS) and ZnO nanoparticles (Nano-ZnO) are two kinds of environmental contaminants that have been frequently detected in natural waters. The potential joint toxicity of PFOS and nano-ZnO remains to be fully elucidated. The objective of this study was to evaluate co-exposure effects of PFOS and nano-ZnO on growth in initial generation (F0) zebrafish after chronic exposure and to examine possible parental transfer of PFOS and nano-ZnO transgenerational effects on the growth of first generation (F1) larvae. When zebrafish (2 h after incubation) were exposed to single- and co-exposure groups for 120 days, bioconcentration resulted in significantly less growth as measured by body length and body weight, higher mortality, and less spawning in the F0 generation. These effects were possibly due to the down-regulation of the expression of Vtg1 genes along with a sex hormone (T/E2) involved in the hypothalamus-pituitary-gonad (HPG) axis. Furthermore, after long-term exposure, less fertilization, less hatching, greater mortality and more malformation were found in the F1 generation. The down-regulation of genes and hormones might be responsible for transgenerational toxicity. This study suggested that chronic exposure to PFOS and nano-ZnO adversely impacts development, reproduction in the F0 generation, and offspring embryonic growth. Highlights • This study demonstrated the possible mechanisms of transgenerational effects in fish. • This study supplemented the current research data in this area. • This study summarized the toxic effects of PFOS and nano-ZnO co-exposure on offspring. [ABSTRACT FROM AUTHOR]

A luminescent MOF 1 was synthesized based on 4-(2-aminopyrimidine-5-yl)benzoic acid. 1 possesses the triple-channel pH sensing ability for strong acid, strong base and weak acid by change of emission wavelength and intensity. 1 can also detect antibiotic moxifloxacin and polyphenol compound tannic acid with LOD at the 10 ppb level. [Display omitted] • A luminescent coordination polymer 1 showed triple-channel specific recognition ability for strong acid-base and weak acid. • This is the first example that a MOF-based pH sensor can quantitatively detect strong acid-base and weak acid, • The sensitivity of 1 to MOX and TA is the highest among fluorescence sensors. A luminescent 1D metal–organic framework [Co(apba) 2 (H 2 O) 2 ] (1) was solvothermal synthesized by using 4-(2-aminopyrimidine-5-yl)benzoic acid (Hapba) as ligand. 1 showed pronounced sensing properties with triple-channel specific recognition ability for strong acid-base and weak acid. From pH = 3.5 to 2.0, the fluorescence quenching percentage reached 1064 % per pH at 412 nm due to the protonation of –NH 2. In the pH region of 3.5–4.5, 1 realizes wavelength-based pH detection depending on the wavelength shift of 30 nm from 412 nm to 382 nm originating from the protonation of nitrogen atom in pyrimidine. In the pH range of 11.5–13.4, the fluorescence quenching percentage reached 2099 % per pH relying on the interaction between OH– and uncoordinated oxygen atom on carboxylate group. This is the first example that a MOF-based pH sensor can detect strong acid-base and weak acid, and their sensitivity to pH is likewise the highest among all pH fluorescent sensors. 1 can also detect antibiotic moxifloxacin (MOX) and polyphenol compound tannic acid (TA) with the limit of detection (LOD) at the 10 ppb level. In the recognition of 1 for MOX, K SV is 2.05 × 105 M−1 (0–100 μM) and LOD reaches 43 nM, which is the first case of a MOF-based MOX sensor so far. The fluorescence response of 1 to TA is also apparent with the K SV value of 7.55 × 105 M−1 (0–0.05 μM) and LOD of 11 nM. This is as well the only instance of MOF material sensing TA to date. Moreover, 1 can continuously track MOX and TA for up to 90 days. The sensing mechanisms of pH, MOX, and TA are also discussed in detail. [ABSTRACT FROM AUTHOR]