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Double perovskite oxides are one of the most promising bifunctional electrocatalysts for efficient oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) due to their adjustable electronic structures via doping with different metal cations or engineering of defects. Herein, we report a systematic study on the tuning of the electronic structure of La2-xSrxNiMnO6 with 0 ≤ x ≤ 1.0 to promote the bifunctional OER/ORR activity. The bifunctional index (ΔE) is substantially reduced with increasing of Sr contents and achieves an optimal value of 0.85 V for La1.4Sr0.6NiMnO6, exceeding that of widely studied LaNiO3. Our study on electronic structures reveals that the enhancement of the ORR and OER activities strongly correlates with the appearance of Ni3+ oxidation states and the upshift of the O 2p-band center promoted by Sr doping. Furthermore, an increase of hole states, derived from Ni3+ states, reduces the energy barrier for the electron transfer from 0.44 to 0.12 eV and hence improves the intrinsic OER activities. The tuning of the electronic structure that leads to higher OER and ORR activities in La2-xSrxNiMnO6 can be extended to other materials for the design of active bifunctional electrocatalysts.

The induction of leaf injuries, including leaf chlorosis and epinasty, by continuous light in tomato plants is one of the most interesting and mysterious phenomena regarding plant interactions with light, the mechanism of which has not yet been revealed. To gain further insights into this particular response of tomato plants, we cultivated tomato seedlings (Solanum lycopersicum cv. Momotaro) for 14 days under continuous light with different ratios of red and blue light and compared their performance to those grown under continuous or 14/10-h photoperiodic white light using novel methods to quantitatively evaluate the level of leaf chlorosis and epinasty. Continuous monochromatic blue light induced severe chlorosis but almost completely alleviated epinasty in tomato leaf. In contrast, continuous monochromatic red light caused a lower level of leaf chlorosis but very severe epinasty. The combination of red and blue light at different ratios significantly reduced both leaf chlorosis and epinasty under continuous light condition. Carbohydrate contents showed no correlation with leaf chlorosis, while glucose and fructose contents showed correlations with the petiole and leaflet curvatures. Histochemical staining with 3,3'-diaminobenzidine and nitro blue tetrazodium chloride also did not reveal any significant buildup of hydrogen peroxide and superoxide anion in monochromatic blue light treatment. Taken together, these results suggest that chlorosis and epinasty are two distinctive leaf injuries caused by continuous light that may follow very different mechanisms, and an overaccumulation of carbohydrates in the leaf may not be the main cause of continuous light-induced leaf chlorosis in tomato.

A new phase of cobalt(II) hydroxyl phosphate γ-Co2(PO4)(OH) has been successfully synthesized through a conventional hydrothermal method. This compound crystallizes in the trigonal system of space group P31m, showing a warping two-legs spin ladder chain structure arranged in an unusual triangular network, in which a new spin-lattice of (3, 6, 4, 6)(4, 62) is built by magnetic Co2+ ions. Magnetic measurements indicate that γ-Co2(PO4)(OH) may show a spin-glass behavior at low temperature.

Understanding environmental factors is essential to maximizing the biomass production of plants. There have been many studies on the effects of the photosynthetic photon flux (PPF), photoperiod and air temperature as separate factors affecting plants, including under a closed transplant production system (CTPS). However, few studies have investigated the combined effects of these factors on plant growth. Germinated tomato and red pepper seedlings were transferred to three different photoperiods with five different photosynthetic photon fluxes (PPFs) at an air temperature of 25/20 &deg, C to investigate plant growth under a different daily light integral (DLI). Three different air temperatures, 23/20, 25/20, and 27/20 &deg, C (photo/dark periods), with five different PPFs were used to examine plant growth under different DIFs (difference between the day and night temperature). Increasing the DLI from 4.32 to 21.60 mol&middot, m&minus, 2&middot, d&minus, 1, either by increasing the photoperiod or PPF, improved the growth of seedlings in both cultivars. However, when comparing treatments that provided the same DLI, tomato seedlings had s significantly higher growth when grown under longer photoperiods and s lower PPF. Even in higher DLI conditions, reduced growth due to higher PPF indicated that excessive light energy was a limiting factor. At 23 and 25 &deg, C, tomato seedlings showed similar correlation curves between growth and PPF. However, at the higher temperature of 27 &deg, C, while the slope of the curve at low PPFs was similar to that of the curves at lower temperatures, the slope at high PPFs was flatter. On the other hand, red pepper seedlings displayed the same correlation curve between growth and PPF at all tested temperatures, and red pepper plants accumulated more dry weight even at higher temperatures. These results suggested that the combination effect was more useful to observe these overall tendencies, especially in reacting to a second factor. This will provide us with more information and a deeper understanding of plant characteristics and how they will behave under changing environments.

The food-derived peptides hydrolyzed from native food protein matrix exhibited various bioactivities and multimeric structures, which make them the promising well-defined nanoplatforms candidates to co-deliver themselves with other bioactive compounds. In this study, zein-egg white derived peptides-chitosan (Z-EWDP-CS) ternary nanoparticles (NPs) were successfully fabricated by the spontaneous assembly to enhance the stability and bioactivity of curcumin (Cur). The novel ternary NPs exhibited a typical nano-spherical structure (138.63 nm, 40.50 mV), and adorable encapsulation efficiency (EE, 93.87%) for Cur. FTIR, XRD and DSC results verified that Cur changed from a crystalline state to an amorphous state, and was successfully entrapped in the cavity of Z-EWDP-CS NPs. Furthermore, the thermal stability, photochemical stability, salt stability, and antioxidant activity were considerably improved in the NPs after the addition of EWDP. Our results demonstrate that the food-derived peptides could be an ideal affinity agent for the co-delivery of themselves with hydrophobic nutraceuticals.

A new tellurate compound Na4CuTeO6 was synthesized by a conventional high-temperature solid state reaction. The titled compound crystallizes in the monoclinic system of a space group C2/c and exhibits a unique spin-chain structure built by planar CuO4 squares and TeO6 octahedra along the [101] direction. Magnetic measurements confirm that Na4CuTeO6 possesses an antiferromagnetic ordering at TN = ∼2.5 K. The intrachain and interchain interactions are estimated by a spin-chain model, showing a less pronounced 1D character in the system.

A new two-dimensional (2D) fluorophosphate compound Na3Cu5(PO4)4F·4H2O with a Cu5 cluster has been synthesized using a conventional hydrothermal method. The compound crystallizes in the orthorhombic crystal system with space group Pnma. The 2D layered structure is formed by cap-like {Cu5(PO4)4F} building units consisting of a Cu4O12F cluster plus a residual cap Cu2+ ion. Magnetic susceptibility exhibits a broad maximum at T2 = 19.2 K due to low-dimensional character followed by a long-range antiferromagnetic ordering at T1 = 11.5 K, which is further confirmed by the specific heat data. High-field magnetization measurement demonstrates a 2/5 quantum magnetization plateau above 40 T. The ESR data indicate the presence of magnetic anisotropy, in accordance with the 2D structure of the system.

A series of heterometallic 3d-4f hydroxyl sulfate-fluoride compound Ln2Cu(SO4)2(OH)3F·H2O (Ln = Gd, Ho, Yb) are synthesized by a conventional hydrothermal method. All of Ln2Cu(SO4)2(OH)3F·H2O family crystallize in the monoclinic system with a space group of P21/c, where the [CuO6]∞ and [Ln2O12F2]∞ chains are perpendicular to each other, featuring a three-dimensional framework. Magnetic measurements confirm that all of Ln2Cu(SO4)2(OH)3F·H2O family (Ln = Gd, Ho, Yb) exhibit a paramagnetic behavior down to 2 K, where the Weiss temperature θ of near zero, positive, and negative values is observed for Gd, Ho, and Yb-analogues, respectively, due to possibly different 3d-4f spin-orbital couplings.

Novel mixed-anionic-group compounds M 2 (SeO 3 )(Te 3 O 7 ) (M = Co 2+ , Ni 2+ ) are successfully synthesized by a conventional hydrothermal method. Two compounds are isostructural which crystallize in the orthorhombic system of a space group Pnma . The framework shows a (MO 6 ) ∞ chain structure along the b -axis, while SeO 3 groups are isolated and Te 3 O 7 groups form the (Te 3 O 7 ) ∞ chains running along the a -axis. This is the first time to realize transition-metal compounds coexisting with Se 4+ and Te 4+ anionic groups. Magnetic measurements show that Co 2 (SeO 3 )(Te 3 O 7 ) possesses an antiferromagnetic ordering at ∼11 K, while Ni 2 (SeO 3 )(Te 3 O 7 ) exhibits a similar antiferromagnetic ordering at ∼31 K. Also, the fitting of magnetic susceptibility using a spin-chain model gives the exchange coupling J /k B = −1.515 K for Co 2 (SeO 3 )(Te 3 O 7 ) and J /k B = −8.963 K for Ni 2 (SeO 3 )(Te 3 O 7 ), respectively.

Cs 2 NaMn 3 F 12 , one of manganese based fluorides A 2 A′Mn 3 F 12 (A = Rb, Cs; A′ = Li, Na, K), has been found to exhibit a typical kagome structure. Here, we report the first successful growth of large-sized single crystals of Cs 2 NaMn 3 F 12 by means of a hydrothermal method. Good quality of grown crystals is confirmed by the XRD and EDS techniques. Magnetic measurements suggest that Cs 2 NaMn 3 F 12 possesses an antiferromagnetic ordering at 2.5 K and a remarkably geometrical frustration effect in the system.

Three new molybdate-tellurites, K2M9(TeO3)4(MoO4)4(OH)4 (M = NiII and CoII) and (NH4)2Cu9II(TeO3)4(MoO4)4(OH)4, have been successfully synthesized by conventional hydrothermal method. Due to the influence of the Jahn-Teller effect, these compounds crystallize in different space groups of rhombohedral R3m, monoclinic P21/c and triclinic P1 for Ni-, Co-, and Cu-analogues, respectively. The topological arrangements of magnetic ions in these compounds show that deficient capped-kagome spin-lattices with kagome positions exhibit different 1/6 depletion. Magnetic and specific heat measurements confirm that K2Ni9(TeO3)4(MoO4)4(OH)4 exhibits a spin-glass behavior at low temperature, while (NH4)2Cu9(TeO3)4(MoO4)4(OH)4 possesses a long-range canted antiferromagnetic ordering with TN ∼ 10.8 K and further shows a 3/5 magnetization plateau in the magnetization curve at low temperature.

New tellurate compounds Na4MTeO6 (M = Co and Ni) were synthesized by a conventional high-temperature solid-state reaction. The title compounds crystallize in the monoclinic system of a space group P2/c and the triclinic system of a space group P, respectively. Both compounds exhibit a zigzag spin-chain structure, in which Na4CoTeO6 shows uniform chains built by Co2+ ions and Na4NiTeO6 shows alternating chains built by Ni2+ ions. Magnetic measurements confirm that Na4CoTeO6 and Na4NiTeO6 possess an antiferromagnetic ordering at TN = ∼3 K and ∼6.5 K, respectively, while a metamagnetic transition can be observed in the magnetization curve with an increasing field at 2 K.

Two new compounds Sr2Cu5(PO4)4X2·8H2O (X = Cl and Br) are synthesized by a conventional hydrothermal method. Sr2Cu5(PO4)4Cl2·8H2O crystallizes in the tetragonal system with a space group of P4212, while Sr2Cu5(PO4)4Br2·8H2O crystallizes in the space group P4/nmm, which are found to have a similar framework of layered structure, in which the crown-like {Cu5(PO4)4X2} building units connect to each other forming a 2D corrugated sheet with vacancies, while the Sr2+ cations are located along the vacancies. The spin lattice of two compounds built by Cu2+ ions shows a new type of corrugated square. Magnetic measurements confirmed that both Sr2Cu5(PO4)4X2·8H2O (X = Cl and Br) exhibit antiferromagnetic ordering at low temperatures. A fit of theoretical model shows exchange interaction J = −25.62 K for the Cl-analogue and J/kB = −26.47 K for the Br-analogue.

A new borophosphate Co3(BPO4)2(PO4)(OH)3 was synthesized by a conventional hydrothermal method. The titled compound crystallizes in the monoclinic system with space group Cc, which exhibits a typical spin-chain structure. In the structural framework, Co2+ ions form a zigzag chain via edge-sharing oxygen atoms, and further the zigzag Co-chains are separated by linear [B2P2O8]∞ chains. Magnetic measurements confirm that Co3(BPO4)2(PO4)(OH)3 possesses an antiferromagnetic ordering at TN = 12 K, while a 1/3 plateau is observed in the magnetization curve at 2 K. The possible spin arrangements for antiferromagnetic, ferrimagnetic, and ferromagnetic states are also suggested.

A series of vanadate compounds Ba3M(V2O7)2 (M = Co, Mn, Mg, or Zn) are synthesized by a conventional high-temperature solid-state reaction. Four compounds are found to exhibit a similar structure, which all crystallize in the monoclinic system of space group P21/c. V5+ ions are tetrahedrally coordinated, forming corner-shared (V2O7)4– groups, while M2+ ions are octahedrally coordinated, forming edge-shared [M2O10] dimers. Isolated {M2V8O28}∞ clusters composed of [M2O10] dimer and (V2O7)4– groups form a pseudo-one-dimensional chain running along the a-axis. Magnetic measurements confirm that both Ba3Co(V2O7)2 and Ba3Mn(V2O7)2 show antiferromagnetic interaction exchanges in the systems, while luminescence measurements confirm that Ba3Mg(V2O7)2 and Ba3Zn(V2O7)2 have a broad emission band from 400 to 650 nm under 256 nm UV irradiation at room temperature.

Cu5(VO4)2(OH)4 (turanite) is a layered compound, exhibiting a copper(II) oxide layer in the [0 1 1] plane composed of edge-sharing CuO6 octahedra. Each Cu-O layer is further separated by VO4 tetrahedra. Closer scrutiny found that the copper(II) oxide layer in the compound represents a totally new geometrically-frustrated lattice, a 1/6 depleted triangular lattice. More specifically, the spin network in the [0 1 1] plane is formed by the alternate ranking of triangular and honeycomb strips. Magnetic measurements show that the Cu5(VO4)2(OH)4 behaves as a spin-1/2 ferrimagnet with a Tc = ∼4.5 K. It exhibits an unusual 1/5 magnetization plateau arising from the competition between antiferromagnetic and ferromagnetic interactions caused by the strong frustration. The possible spin-arrangements are also suggested.

A selenite chloride, Na2Cu7(SeO3)4O2Cl4 (), was prepared via a conventional hydrothermal method. Na2Cu7(SeO3)4O2Cl4 crystallizes in the triclinic space group P1[combining macron] and features an isolated reverse triangular dipyramid Cu7, which is assembled with two corner-shared Cu4 tetrahedral units. Magnetic measurements suggest that shows the spin-frustration effect with antiferromagnetic ordering at ∼5 K, while an unusual magnetization plateau is observed at an applied field of4 T.

Single crystals of the title compounds are prepared by hydrothermal reaction of 1.5:0.5:2 molar mixtures of CuSO4, TeO2, and NaOH or KOH (autoclave, 190 °C, 5 d; cooling rate of ≈3 °C/h).

Two barium copper phosphates, BaCu2(PO4)2(H2O) (1) and Ba2Cu(HPO4)(PO4)(OH) (2), were synthesized under mild hydrothermal conditions. The Cu cation in 1 adopts a CuO4(H2O) square pyramidal coordination configuration, forming alternating chains along the b axis through alternative corner and edge sharing, while the geometry of the Cu center in 2 is a CuO4(OH)2 octahedron which further connects each other by edge sharing to constitute uniform chains along the b axis. Magnetic behaviors of both compounds were analyzed by susceptibility, magnetization and heat capacity measurements. The dominant intrachain couplings are antiferromagnetic in 1 with a long-range ordering at 14 K and ferromagnetic in 2 without long-range ordering above 2 K. The first principles calculations indicate that the intrachain ferromagnetic couplings in 2 originate from Cu(1)-O(7)H-Cu(1) dpσ correlation superexchanges. The susceptibility data of compounds 1 and 2 are fitted by using suitable antiferromagnetic chain and ferromagnetic chain models, respectively. In addition, we report the results of the infrared and thermal measurements of both the compounds.

Two new tellurite–sulfates A2Cu5(TeO3)(SO4)3(OH)4 (A = Na, K) have been synthesized by a conventional hydrothermal method. Both compounds feature 1D kagome strip structure built by distorted CuO6 octahedra, which can be regarded as the dimensional reduction of kagome lattice. Magnetic measurements confirmed that the titled compounds possess antiferromagnetic ordering at low temperature, while a field-induced magnetic transition can be observed at critical field. To the best of our knowledge, this is the first time to obtain distorted kagome strip compounds.

Ca5M4V6O24 (M: Co, Ni) are prepared by reaction of CaCO3, CoC2O4 or Ni(OAc)2, and V2O5 (alumina crucible, 900 resp.

Co7V4O16(OH)2(H2O) is obtained in the attempt to prepare a Sr-Co-V-O phase via hydrothermal reaction of a 2:1:4 molar aqueous mixture of ScCl2, V2O5, and Co(OH)2 (autoclave, 200 °C, 3 d).

Five different species of selected broad-spectrum antibiotic lactic acid bacteria isolated from extremely high-cold areas were used as starters to ferment indigenous forage oats and wheatgrass under rigid alpine climatic conditions. The five isolates were Lactobacillus plantarum QZ227, Enterococcus mundtii QZ251, Pediococcus cellicola QZ311, Leuconostoc mesenteroides QZ1137 and Lactococcus lactis QZ613, and commercial Lactobacillus plantarum FG1 was used as the positive control and sterile water as the negative control. The minimum and maximum temperatures were -22°C and 23°C during the fermentation process, respectively. The pH of wheatgrass silage fermented by the QZ227 and FG1 inocula reached the expected values (≤4.15) although the pathogens detected in the silage should be further investigated. All of the inocula additives used in this study were effective in improving the fermentation quality of oat silage as indicated by the higher content of lactic acid, lower pH values (≤4.17) and significant inhibition of pathogens. QZ227 exhibited a fermentation ability that was comparable with the commercial inoculum FG1 for the whole process, and the deterioration rate was significantly lower than for FG1 after storage for 7 months. The pathogens Escherichia coli, mold and yeast were counted and isolated from the deteriorated silage. E. coli were the main NH3-N producer while F. fungi and yeast produced very little.

Lactic acid bacteria (LAB) can be used as silage additives to ensure rapid and vigorous fermentation at early stages of ensiling. We predicted that the optimal LAB inoculation dosage for forage at ambient temperature (15–38°C) would be different from that at cold temperature (4°C). In this study, Lactobacillus plantarum QZ227, isolated from a wheat landrace in alpine regions of Qinghai, China, and commercial L. plantarum FG1 were used as inoculum, with sterile water as control. The effects of inoculum dosage on the fermentation quality of oat (Avena sativa L. cv. Qinghai) and wheat (Triticum aestivum L. cv. Yumai No. 1) silage at ambient temperature (15–38°C) and at 4°C were investigated in laboratory experiments. Little or no improvement in silage quality occurred upon increasing the inoculum dosage at ambient temperature. By contrast, a lower pH and NH3-N content, and a higher LAB count and lactic acid content, were observed at 4°C. Furthermore, the growth of Escherichia coli was inhibited effectively at the lower temperature, and silage quality was positively correlated with increasing inoculum dosage (P