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Constructing an internal electric field (IEF) within the hematite (Fe2O3) photoanode for highly efficient water oxidation performance with facilitated charge transfer and separation remains still a significant challenge. Unlike the conventional approach of creating interfacial electric fields through heterojunction design by introducing another semiconductor, a novel strategy is proposed for engineering localized n‐p homojunctions on the surface of Fe2O3 photoanode using gradient Zn2+ doping strategy. By implementing this approach, the inherent n‐type characteristics of Fe2O3 can be transformed into p‐type, thereby facilitating the formation of an n‐p junction with robust IEF, which enables more efficient charge separation and transfer. Additionally, the gradient Zn2+ doping is accompanied by the generation of oxygen vacancies, which further improves the charge transfer efficiency and accelerates water oxidation kinetics. As expected, the photocurrent density of optimized Fe2O3 photoanode at 1.23 V versus reversible hydrogen electrode is ≈2.6‐fold that of Fe2O3. This work provides a novel perspective on the design of localized n‐p homojunction within photoanodes for achieving high solar energy conversion efficiency. [ABSTRACT FROM AUTHOR]

Constructing heterostructural photoanodes is attractive for elevating the photoelectrochemical (PEC) performance, however, it is a long‐standing challenge to achieve highly efficient interfacial charge transfer. Herein, a CoFe metal‐thiolate framework (CoFe MTF)/Fe2O3 photoanode connected by an interfacial Fe─O─N/S bond is designed to modulate the behavior of charge carriers and improve water oxidation performance. It is disclosed that this interfacial bond functions as a direct charge transfer bridge between shallow trap states of Fe2O3 and CoFe MTF, leading to prolonged carrier recombination lifetimes (85 ns for CoFe MTF/Fe2O3 compared to 37 ns for Fe2O3) and enhanced charge transfer efficiency. Alternatively, a robust interfacial electric field is established in the CoFe MTF/Fe2O3 p–n heterojunction, facilitating efficient charge transfer. As expected, the CoFe MTF/Fe2O3 photoanode exhibits significant enhancement in water oxidation, resulting in a three‐fold increase in photocurrent density compared to pristine Fe2O3. This study highlights the significance of designing interfacially bonded heterostructural photoelectrodes to regulate the transfer characters of charge carriers. [ABSTRACT FROM AUTHOR]

One new citrinin monomer derivative (1), and two new natural products α-pyrone analogues (2a and 2b), were isolated from the sponge derived fungus Penicillium sp. SCSIO 41302. Their structures were determined by extensive spectroscopic analysis, chiral-phase HPLC analysis, modified Mosher's method, ECD calculations, and X-ray single-crystal diffraction. Bioactivity screening showed that compounds 2b and 8 exhibited obvious inhibitory activities against pancreatic lipase and acetyl cholinesterase with IC50 values of 48.5 and 4.8 μM, respectively, which indicated that different chiral center between enantiomers (2a and 2b) might result in different biological activities (IC50 value against PL for 2a >100 μg/ml). [ABSTRACT FROM AUTHOR]

A new diketopiperazine, cyclo-(d-8-acetoxyl-Pro-l-Leu) (1), together with eight known compounds (2–9) including three enterotoxins (2–4), four diketopiperazines (5–8) and maltol (9), were isolated from the mangrove derived-soil Streptomyces sp. SCSIO 41400. The planar structures of all compounds were determined from analysis of NMR spectra, MS, optical rotation and comparing with literature data. The absolute configuration of compound 1 was assigned by electronic circular dichroism (ECD). The isolated compounds (1–9) were tested for their acetyl cholinesterase (AChE) and pancreatic lipase (PL) enzyme inhibitory activities. Among them, the new diketopiperazine (1) displayed preferable PL enzyme inhibitory activity with IC50 value of 27.3 μg/mL, while compounds 2, 5 and 6 showed weak PL enzyme inhibitory activity. Further molecular docking simulation exhibited that compound 1 could be well bind with the catalytic pocket of the PL. Besides, compound 9 showed moderate antibacterial activity against Methicillin-resistant Staphylococcus aureus with MIC value of 12.5 μg/mL, which was comparable to that of the positive control ampicillin with MIC value of 3.125 μg/mL. [ABSTRACT FROM AUTHOR]

Functionalization of metal-oxide semiconductors by noble metal nanoparticles is one of the most efficient methods for enhancing the gas-sensing property of semiconducting sensors. Herein, we synthesized a series of Au-loaded hierarchical WO3 hollow microspheres (Au-WO3) via a facile modified solvothermal method combining with wet impregnation method. The structure, elemental composition, and morphology of the synthesized materials were characterized by X-ray powder diffraction, X-ray photoelectron spectroscopy, scanning electron microscope, and transmission electron microscopy. The results show that the materials are uniform and independent WO3 hollow microspheres, and Au nanoparticles are well distributed on the surface of WO3. The gas sensing properties of Au-WO3 materials were investigated and the results suggest that Au loading could greatly improve gas sensing performance of WO3 to aromatic compounds, especially toluene and xylene. Among the samples with different Au loading content, the one with 1.5 wt% Au (G3) exhibits the highest responses toward toluene and xylene at 340 °C. Moreover, the G3 sensor presents good responses, short response/recovery time, excellent selectivity, good reproducibility, and long-term stability to toluene and xylene. Excellent gas sensing properties of Au-WO3 material make it a good candidate for detecting toluene and xylene. [ABSTRACT FROM AUTHOR]

Lithium-sulfur (Li–S) batteries have attracted wide attention due to their outstanding properties of high theoretical specific capacity and energy density. However, drawbacks such as the polysulfide shuttle effect have hampered their further practical application. Metal–organic frameworks (MOFs) have stimulated increasing interest in energy storage and conversion. In MOFs, the metal ions can be activated to provide open metal Lewis acid sites to restrain polysulfides. Aiming at sensible solutions, a novel manganese cluster-based MOF equipped with cubic cages, which are walled with abundant open-metal sites (OMSs) obtained from 9-manganese nodes, is used as the cathode host of Li–S batteries. The activated MOF not only provided physical capture and chemical adsorption against polysulfide shuttle but also allowed efficient impregnation of sulfur to facilitate mass transport. Benefiting from these synergetic effects, the composite cathode delivers enhanced electrochemical performance. The battery showed a remaining capacity of about 990 mA h g−1 after 200 cycles at 0.2C and an approximately repeatable rate performance. Significant contribution of the exposed functional metal sites was demonstrated by XPS and SEM of the electrode materials. [ABSTRACT FROM AUTHOR]

In this paper, 17 compounds (1–17) were isolated from the leaves of Hemp (Cannabis sativa f. sativa). Among the isolates, two were determined to be new spirans: cannabispirketal (1), andα-cannabispiranol 4’-O-β-D-glucopyranose (2) by 1D and 2D NMR spectroscopy, LC-MS, and HRESIMS. The known compounds7,8,10,13,15, and16were isolated from Hemp (C. sativa f. sativa) for the first time. Furthermore, compounds8and13were isolated from the nature for the first time. All isolated compounds were evaluated for cytotoxicity on different tissue-derived passage cancer cell lines through cell viability and apoptosis assay. Among these compounds, compounds5,9and16exhibited a broad-spectrum antitumor effect via inhibiting cell proliferation and promoting apoptosis. These results obtained have provided valuable clues to the understanding of the cytotoxic profile for these isolated compounds from Hemp (C. sativa f. sativa). [ABSTRACT FROM PUBLISHER]

A flexible and highly efficient air cathode is fabricated via a simple electro‐deposition approach. This cathode exhibits a series of considerable electrochemical performances, in particular a good cycling performance (more than 70 cycles with the capacity limited 1000 mA h g−1). Based on this flexible cathode, a Li–O2 battery with flexible properties is also assembled, which can power a commercial LED normally. [ABSTRACT FROM AUTHOR]

The pressing demand on the electronic vehicles with long driving range on a single charge has necessitated the development of next-generation high-energy-density batteries. Non-aqueous Li-O2 batteries have received rapidly growing attention due to their higher theoretical energy densities compared to those of state-of-the-art Li-ion batteries.To make them practical for commercial applications, many critical issues must be overcome, including low round-trip efficiency and poor cycling stability, which are intimately connected to the problems resulting from cathode degradation during cycling. Encouragingly, during the past years, much effort has been devoted to enhancing the stability of the cathode using a variety of strategies and these have effectively surmounted the challenges derived from cathode deteriorations,thus endowing Li-O2 batteries with significantly improved electrochemical performances. Here, a brief overview of the general development of Li-O2 battery is presented. Then, critical issues relevant to the cathode instability are discussed and remarkable achievements in enhancing the cathode stability are highlighted. Finally, perspectives towards the development of next generation highly stable cathode are also discussed. [ABSTRACT FROM AUTHOR]

The first concise synthesis of the bidesmosidic oleanolic acid saponins 1- 3 isolated from Fadogia ancylantha (Makoni tea) have been accomplished through a 'one-pot sequential glycosylation' strategy with two glycosyl 1-(trichloroacetimidate)s as glycosyl donors. The synthesized natural products 1- 3 were then evaluated for their inhibitory activities against α-glucosidase, α-amylase, and lipase. Among the assayed compounds 1- 3, compound 1 showed strong α-glucosidase and α-amylase inhibition, with IC50 values of 160 and 180 μ M, respectively. Moreover, compounds 2 and 3 showed strong inhibition against α-glucosidase and lipase, with the respective IC50 values of 170 and 190 μ M, and 190 and 200 μ M. [ABSTRACT FROM AUTHOR]

Cobalt oxide nanosheets (Co[sub 3]O[sub 4] NSs) are grown on carbon paper (CP) by an efficient and facile electrodeposition method. When directly used as free-standing cathode for lithium-oxygen batteries, the Co[sub 3]O[sub 4] NSs/CP is found to be robust and shows enhanced specific capacity and cycling stability. [ABSTRACT FROM AUTHOR]

Chemical synthesis of a trisaccharide related to the cytotoxic triterpenoid saponins isolated from the bark of Albizia procera has been accomplished through a concise stepwise glycosylation strategy starting from commercially available D-xylose, 2-acetamido-2-deoxy- D-glucose and L-arabinose. The target trisaccharide was designed with a 4-methoxyphenyl (MP) aglycone to extend the scope of conversion to suitable glycoconjugates via selective removal of 4-methoxyphenyl (MP) group. An unexpected phenomenon, i.e., the arabinosyl residue assumed the 1 C4 conformation instead of the typical 4 C1 form, was observed. Deprotection could restore the normal conformation. [ABSTRACT FROM AUTHOR]

Ultralong cycle life, high energy, and power density rechargeable lithium-ion batteries are crucial to the ever-increasing large-scale electric energy storage for renewable energy and sustainable road transport. However, the commercial graphite anode cannot perform this challenging task due to its low theoretical capacity and poor rate-capability performance. Metal oxides hold much higher capacity but still are plagued by low rate capability and serious capacity degradation. Here, a novel strategy is developed to prepare binder-free and mechanically robust CoO/graphene electrodes, wherein homogenous and full coating of β-Co(OH)2 nanosheets on graphene, through a novel electrostatic induced spread growth method, plays a key role. The combined advantages of large 2D surface and moderate inflexibility of the as-obtained β-Co(OH)2/graphene hybrid enables its easy coating on Cu foil by a simple layer-by-layer stacking process. Devices made with these electrodes exhibit high rate capability over a temperature range from 0 to 55 °C and, most importantly, maintain excellent cycle stability up to 5000 cycles even at a high current density. [ABSTRACT FROM AUTHOR]

The four hederagenin glycosides 1- 4 were efficiently synthesized through one-pot sequential glycosylations with glycose 1-(trichloroacetimidate)s as donors, resulting in a significantly simplified synthetic procedure without isolation of glycosylation intermediates. The activity of the synthetic hederagenin glycosides 1- 4 against α-glucosidase type IV was evaluated; hederagenin glycoside 4 containing an α- L-rhamnopyranosyl unit showed the best activity with an IC50 value of 47.9 μ M. [ABSTRACT FROM AUTHOR]

Y. Zhang, X.‐B. Zhang, and co‐workers report on page 4345 an electrostatic‐induced spread‐growth method to homogeneously coat CoO on graphene. Binder‐free electrode with excellent structural stability can then be easily prepared by layer‐by‐layer stacking. As an anode for Li‐ion batteries, the asprepared electrode exhibits a high rate capability and excellent cycle stability up to 5000 cycles. This opens up a promising strategy to develop high‐performance anodes for next‐generation LIBs. [ABSTRACT FROM AUTHOR]

Highlights • Clematis terniflora var. mandshurica is similar to the other Ranunculaceae in many embryological features. • The male gametophytes matured faster than female gametophytes about two to four stages. • Epidermis and endothecium were both fibrous thickings in mature anther wall. • A megaspore mother cell was formed directly. Abstract Embryology can provide valuable information for determining taxonomic and phylogenetic relationships at the genus level. However, embryological information is fragmentary for the genus of Clematis. Herein, we studied the anther and ovule development of Clematis terniflora var. mandshurica using paraffin sections to examine microsporogenesis, microgametogenesis, megasporogenesis and macrogametogenesis in this plant. Tetrasporangiate anther, successive microsporocyte cytokinesis, and glandular tapetum, or occasionally amoeboid tapetum were observed in C. terniflora var. mandshurica. This plant's microspore tetrads were mostly tetrahedral, and occasionally symmetrical, after meiosis. The anther wall was comprised of an epidermis and endothecium, both with fibrous thickenings in the mature anthers. Pollen grains were symmetrical, oblate, tricolpate, and two-celled. As for the ovary, it had one chamber with a few degraded ovules and a single normal one, which was anatropous, unitegmic, and tenuinucellate, and formed a Polygonum -type embryo-sac. Only one archesporial cell was present, and developed directly into a megaspore mother cell, which later formed a linear tetrad of megaspores. Larger dikaryocytic antipodal cells could also be observed in the mature embryo sac. This species might belong to a relatively primitive and transitional clade within the genus Clematis. To our knowledge, this study documented the embryological characters of C. terniflora var. mandshurica in detail for the first time and provided more information on the embryology of the genus Clematis. [ABSTRACT FROM AUTHOR]

Detection of formaldehyde ( FA ) in the atmosphere is of significant importance because exposure to FA may cause serious health problems such as sick-house syndrome, leukemia, and cancer. Modifying metal oxide semiconductors (MOSs) with noble metal nanoparticles (NPs) is an efficient method to enhance FA -sensing properties. Herein, a series of Au 25 nanocluster (NC)-decorated three-dimensionally ordered macroporous In 2 O 3 materials (Au 25 /3DOM In 2 O 3 ) is created, and the loading amount of Au 25 NCs was optimized based on FA responses. To reveal the effect of gold size on FA responses, we constructed Au 144 NC-loaded 3DOM In 2 O 3 and Au NP (2.9 nm)-modified 3DOM In 2 O 3 and compared their gas-sensing properties with the optimal Au 25 /3DOM In 2 O 3 . The results show that in comparison with its counterparts, the optimal Au 25 /3DOM In 2 O 3 presents higher sensitivity, shorter response/recovery times, better selectivity, and excellent reproducibility. More attractively, the responses to FA are dependent on the size of Au particles loaded on In 2 O 3 . We suggest that the enhanced FA responses for the optimal material are mainly attributed to the electronic and chemical-sensitization effects of Au 25 NCs, and the size-dependent effect of FA responses is ascribed to the size of Au NPs affecting the formation of oxygen-adsorbing species. This work provides an efficient way for fabricating noble metal NP-loaded MOSs with tunable gas-sensing properties.

Solar-driven photocatalytic CO 2 reduction into CH 4 with H 2 O is considered to be a promising way to alleviate the energy crisis and greenhouse effect. However, current CO 2 photoreduction technologies tend to overlook the role of photooxidation half reaction as well as the effect of the protons produced by water oxidation on CH 4 generation, resulting in low CO 2 conversion efficiency and poor CH 4 selectivity. In the present study, a series of chloride-modified Bi 2 WO 6 nanosheets were constructed in view of chloride-assisted photocatalytic water oxidation. The results show that the CH 4 yield of the synthesized sample can be enhanced up to about 10 times compared to that with no Cl - modification. Besides, the selectivity of CH 4 can be regulated by the loading amount of chloride, varying from 51.29% for Bi 2 WO 6 to 94.98% for the maximum. The increase of product yield is attributed to chloride modification, which not only changed the morphology of the catalyst, but also modified the pathway of water oxidation. Further studies on intermediate products and the density functional theory calculation confirm that the Cl - ions on Bi 2 WO 6 nanosheets not only promote H 2 O oxidation, but also lower the energy barrier for intermediate *CHO generation, thus facilitating CH 4 production. The results gained herein may provide some illuminating insights into the design of a highly selective photocatalyst for efficient CO 2 reduction.

A number of inherent and thorny obstacles still stand in the way of the practical application of Li-O 2 batteries, which require development of an advanced lithium anode and O 2 cathode. Herein, the strategy of a symmetrical Li-O 2 battery is presented. Specifically, Cu nanoneedle arrays with a nanoengineered Au coating are grown directly on a Cu foam substrate (Au/Cu@FCu), which can act as both the anode backbone and the cathode in a Li-O 2 battery. The excellent conductivity, high porosity, large specific surface, and superior lithiophilicity as well as high catalytic activity of the Au/Cu@FCu electrodes can simultaneously regulate the deposition behavior of the lithium metal in the anode and catalyze the formation/decomposition of Li 2 O 2 in the cathode. As a result, the Li uniformly deposited on the Au/Cu@FCu anode without Li dendrites, showing a high Coulombic efficiency over 96% and a long and stable cycle lifetime over 970 h. At the same time, the Au/Cu@FCu cathode demonstrates extremely low overpotentials (0.64 V) and a much higher specific capacity of 27 270 mAh g -1 compared to the Li-O 2 batteries with a carbon-free cathode reported to date. Moreover, the "ebb and flow" phenomenon of the anode and cathode morphology is also observed in the Li-O 2 battery.

Camellia japonica (Naidong), a Tertiary relict species with abundant morphological characteristics and special genetic characteristics, is the northernmost distributed population of C. japonica. The seedlings of Naidong were subjected to two light regimes (65%, 15% of full sunlight, respectively) and three water supply regimes (75%, 50% and 25% of field capacity, respectively). Our objectives were to reveal the ecophysiological responses of Naidong under different drought and shade conditions and to examine the four existing hypotheses explaining the responses of Naidong seedlings to the interactions of shade and drought. The results showed that 15% of full sunlight reduced the growth of seedlings. Compared with those under 65% of full sunlight condition, the net photosynthetic rate, transpiration rate and chlorophyll content of seedlings under 15% of full sunlight condition were decreased by 63.3%, 82.9% and 17.5%, respectively. In contrast, the specific leaf area, leaf water content and maximal quantum yield under 15% of full sunlight condition were enhanced by 60.3%, 8.3% and 6.4%, respectively. Drought limited the growth of seedlings,decreased their height and basal diameter. The net photosynthetic rate, transpiration rate and stomatal conductance of seedlings significantly decreased with the increases of drought stress, with their minimum values being 0.83 μmol·m -2 ·s -1 , 0.30 μmol·m -2 ·s -1 and 11.56 mmol·m -2 ·s -1 , respectively. With the increases of drought stress, the contents of peroxidase and catalase showed a general declining trend, but the contents of malondialdehyde and proline significantly increased. The treatment 15% of full sunlight alleviated the negative effects of drought on Naidong seedlings, which supported the above-ground facilitation hypothesis. Our results indicated that Naidong seedlings could respond and acclimate to environmental changes through various mechanisms, and the seedlings might normally grow under broad ranges of light and water stresses. In addition, providing ideal light and water conditions for the Naidong seedlings could facilitate its application in gardening.

An ultrathin, lightweight, and wearable Li-O 2 battery with a novel segmented structure is first fabricated by employing a "break up the whole into parts" strategy. Superior battery performance including low overpotential, high specific capacity, good rate capability, excellent cycle stability, and high gravimetric/volumetric energy density (294.68 Wh kg -1 /274.06 Wh L -1 ) is successfully achieved even under repeatedly various deformation., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The leaves of four evergreen plants, i.e., Fatsia japonica, Nerium indicum, Mahonia bealei and Acer cinnamomifolium were used as the experimental materials. By measuring the changes of in vitro leaf in soluble sugar, soluble protein, free proline, POD activity, chlorophyll content and relative electrolytic conductivity under aritificial simulated low temperature, combining the measurements of SPAD, leaf surface features and anatomical changes in organizational structure in the process of natural wintering, the cold resistance of four evergreen tree species was evaluated comprehensively. The results showed that in the process of artificial low temperature stress, the chlorophyll content of the leaves of four evergreen species decreased, the content of soluble protein pea-ked at -20 ℃, and the soluble sugar, free proline, POD activity and relative electrolytic conductivity showed an overall upward trend. The semilethal temperatures of four species were -8.0, -13.4, -19.4 and -14.8 ℃, respectively. During the winter, the leaf SPAD of the four species changed markedly, reflecting that the change of relative chlorophyll content was related to the change of temperature. Meanwhile, the leaf thickness, cutin layer thickness, stockade tissue thickness and tightness of four species increased and the plasmolysis occurred thereafter. Also the content of starch grains and calcium oxalate cluster crystal increased. The typical stomatal pits and the intensive non-glandular trichome within the pits of N. indicum and the sclerenchyma of M. Bealei could improve the cold resistance of plants to some extent. In addition, the phenomena like the breakage of wax layer in leaf surface, the fracture of epidermal hair and the deformation of palisade tissue indicated that plants were damaged to a certain extent by low temperature.

In this study, the adaptability of leaf shape, structure and stomata characteristics of Camellia sasanqua to temperature variation in natural process was investigated by field morphological observation, conventional paraffin section and scanning electron microscopy methods. The results showed that, as the temperature decreased, the leaf color changed from green to dark green, toge-ther with white and purple spots on the leaves. The relative conductivity and the percentage of wi-thered leaves increased initially and then decreased during this period. The highest percentages of relative conductivity and withered leaves in March 2015 were 56.0% and 25.4%, respectively. Different leaf tissue structure indexes, including middle vein thickness, leaf thickness, upper and lower epidermis thickness, upper and lower cuticle thickness, palisade tissue thickness, spongy tissue thickness, ratio of palisade tissue to spongy tissue, cell tense ratio and vein protuberant degree were also determined during the natural temperature change from September 2014 to April 2015. Gradually, these parameters increased initially and then decreased with the decrease of temperature except spongy ratio, which showed the opposite trend. These indicators above changed significantly in different months. Stomata length and width were not significantly changed in October 2014, December 2014 and March 2015, while the percentage of completely closed stomata was higher in March 2015, compared with other months. Taken together, we proposed that the improved adaptability of cold tolerance of C. sasanqua relies on the changes of leaf structure and stomatal closure.

A novel cable-type water-survivable flexible Li-O2 battery is developed with a hydrophobic and free standing gel polymer electrolyte. Superior battery performances are successfully achieved under mechanical twisting, bending, and even immersed in water conditions, showing the high promise to power next-generation versatile flexible electronics., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A flexible freestanding air cathode inspired by traditional Chinese calligraphy art is built. When this novel electrode is employed as both a new concept cathode and current collector, to replace conventional rigid and bulky counterparts, a highly flexible and foldable Li-O2 battery with excellent mechanical strength and superior electrochemical performance is obtained., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)