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This paper introduces a novel approach to reducing statistical errors in generative models, with a specific focus on generative adversarial networks (GANs). Inspired by the error analysis of GANs, we find that statistical errors mainly arise from random sampling, leading to significant uncertainties in GANs. To address this issue, we propose a selective sampling mechanism called space‐filling sampling. Our method aims to increase the sampling probability in areas with insufficient data, thereby improving the learning performance of the generator. Theoretical analysis confirms the effectiveness of our approach in reducing statistical errors and accelerating convergence in GANs. This research represents a pioneering effort in targeting the reduction of statistical errors in GANs, and it demonstrates the potential for enhancing the training of other generative models. [ABSTRACT FROM AUTHOR]

Regarded as one of the popular cathode materials in aqueous zinc ion batteries (ZIBs), VS2 has unsatisfied cycling stability and relatively low capacity owing to its poor conductivity and low mechanical properties. To this regard, compositing VS2 with high‐conductive 2D transition metal carbide (MXene) has been an effective method recently. However, the Zn dendrite on the anode electrode derived from the uncontrollable sluggish migration of solvated Zn2+/H2O ions seriously threatens the application safety of ZIB batteries. To effectively regulate the diffusion of zinc ions, in this work a conductive polymeric electrolyte of sulfonated polyaniline (SPANI) is added in the electrolyte solution. Under the Zn2+/SPANI interactions confirmed by X‐ray diffraction, Raman, and zeta potential experiments, the Zn2+/H2O combination is weakened, and the deposition rate of Zn2+ is increased evaluated by the galvanostatic intermittent titration technique. Theoretical simulation shows that the electrostatic shielding by SPANI combining Zn2‐ at the zinc/electrolyte interface has important contribution to the significant suppression of Zn dendrite. Accordingly, the fabricated VS2@MXene||ZnSO4+SPANI||Zn battery shows high capacity (368.0 mAh g‐1 at 0.1 A g‐1), which remains 96% after 5000 cyclic charge–discharge operations. This work develops an available strategic idea for suppressing growth of metallic dendrites to improve the ZIB performances. [ABSTRACT FROM AUTHOR]

Herein, a high performance bifunctional catalyst was prepared by inserting N‐doped nanomaterials into Ni−Co layered dihydroxides (NiCo‐LDH) nanoplates for high performance zinc‐air battery. By using self‐assembly of perylenetetracarboxylic dianhydride and dicyandiamide in the hydrothermal condition, a nitrogen‐containing super thin carbonaceous nanosheet is achieved after calcination. Then NCM inserted NiCo‐LDH nanoplates attached to nickel foam (NiCo‐LDH/NCM@NF) are synthesized by in‐situ production of NiCo‐LDH species on NCM wrapped NF. The specific NCM improves the conductivity, electroactive surface area and the ORR/OER bifunctional activity of NiCo‐LDH nanoplates. In addition, benefited from the formed rich oxygen vacancies, NiCo‐LDH/NCM@NF delivers the low OER overpotential (352 mV at 50 mA cm−2) and boosted ORR performance with a half‐wave potential of 0.765 V vs RHE. As the air cathode, the fabricated ZAB devices show a satisfactory capacity of 685 mAh g−1 and the energy density of 158 mW cm−2. [ABSTRACT FROM AUTHOR]

Active bifunctional electrocatalysts for both oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) are badly required for high‐efficiency zinc–air batteries (ZABs). Herein, a Fe‐alloyed MoNi nanohybrid (MoNiFe) as bifunctional catalyst is reported. The alloyed MoNiFe architecture with the decreased size compared with MoNi is obtained by a hydrothermal reduction method, which enhances the exposed active sites and promotes the charge transfer. Accordingly, MoNiFe exhibits good bifunctionality, with a positive half‐wave potential (0.896 V) near Pt/C (0.812 V) in ORR reaction and a low overpotential (0.295 V) similar to IrO2 (0.29 V) in OER process. The as‐derived rechargeable ZAB cells based on the bifunctional MoNiFe catalyst show the peak power density of 58 mW cm−2 with a high open‐circuit voltage of 1.319 V. Thus, this work paves a new alloying avenue for synthesizing effective bifunctional electocatalysts for ZABs. [ABSTRACT FROM AUTHOR]

Electrolysis of water is a promising reaction to produce the sustainable energy of hydrogen that proceeds commonly by assistance of a highly efficient catalyst. Now, the development of highly efficient and low‐cost electrocatalysts has stimulated increasing interest. Herein, a new composited electrocatalyst of MoxC embedded in N‐doped carbon nanosheets (MoxC@NCS) is successfully prepared from a self‐assembly route. Due to the expanded interlayers of carbon NCS and enhanced active defective sites induced by two‐materials compositing, the as‐synthesized MoxC@NCS affords splendid hydrogen evolution reaction (HER, overpotential of 160 mV), as well as remarkable oxygen evolution reaction (OER, overpotential of 360 mV) at 10 mA cm−2 in alkaline water splitting. In view of earlier excellent performances, the bifunctional MoxC@NCS catalyst shows a low cell voltage of 1.56 V at 10 mA cm−2 in overall water splitting. In addition, the MoxC@NCS exhibits an outstanding stability after long‐term electrochemical measurements. These findings extend the potential application of carbon‐supported non‐noble metallic catalysts, being of great significance in sustainable energy‐related fields. [ABSTRACT FROM AUTHOR]

2D composited nanosheets of Mo2C/CoMoS4 are synthesized by a hydrothermal approach to obtain a bifunctional water‐splitting electrocatalyst for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in aqueous alkaline solution. Due to the richened defects formed on the 2D catalyst, the as‐derived Mo2C/CoMoS4 exhibits high activity. At 10 mA cm−2, the HER and OER overpotentials of the 2D Mo2C/CoMoS4 nanosheets are just 117 and 250 mV, respectively, with the corresponding Tafel slope of 90 and 75 mV dec−1, near to the commercial Pt/C and IrO2. X‐ray photoelectron spectroscopy proves the strong interactions between Mo2C and CoMoS4 and the Raman analysis certifies the presence of richened defects in Mo2C/CoMoS4. Moreover, the Mo2C/CoMoS4 possesses a long‐term catalytic stability, showing potential application in the water splitting. [ABSTRACT FROM AUTHOR]

With the development of light‐weight and bendable electric devices, nowdays, solid‐state supercapacitive devices have attracted great attention, in which the classic polymeric electrolytes such as polyvinyl alcohol and polyethylene oxide copolymers are generally used. However, the microphase separation in these polymers and low conductivity affect the ions transfer and the energy‐storage performance. In this work, a crosslinked sodium polyacrylate gel (NaPA) is synthesized to replace conventional polymeric electrolyte. Because NaPA is a kind of polymeric salt which has high native degree of ionization in water, the NaPA gel shows low resistance to ion transportation. By using NaPA gel as the electrolyte and carbon cloth as current collector, a flexible solid asymmetric supercapacitor assembled by positive NaFePO4/carbon cloth and negative activated carbon/carbon cloth electrode shows the maximum capacitance of 46.33 mF cm−2 at 1 mA cm−2, with a high stability of 87.33 % retention during 5000 charge and discharge cycles. Moreover, this flexible asymmetric supercapacitors showed nearly unchanged capacitance under different bending angles. It is found that the Na+ diffusion coefficient in NaFePO4/CC//NaPA supercapacitor is 8.05×10−14 cm2 ⋅ s, remarkable higher than CC//NaPA and NaFePO4/CC//PVA. The high diffusion coefficient and low resistance of NaPA lead to excellent capacitave performance of NaFePO4/CC//NaPA, delivering a good application prospect. [ABSTRACT FROM AUTHOR]

In this work, the nickel‐based metal organic framework (Ni‐MOF) is attached to the conductive carbon cloth (CC) by using a hydrothermal reaction. In order to make MOFs strongly interacted with CC, polymeric molecules of polyaniline (PANI) are deposited on Ni‐MOF@CC employing an in–situ polymerization method. The PANI shows a three‐dimensional fiber‐network morphology. Due to the improved electrical conductivity and the porous networks, the electrochemistry property of the obtained flexible PANI/Ni‐MOF@CC is greatly enhanced compared with Ni‐MOF@CC. The specific capacitance of PANI/Ni‐MOF@CC reaches 109 F cm−2 (573 F g−1). The optimum energy density of PANI/Ni‐MOF@CC at 0.1 A cm−2 can be 7 mWh cm−2 with power density of 70 mW cm−2. Because the fiber networks of PANI on MOF enhances the interactions between MOF and CC, the PANI/Ni‐MOF@CC shows high stability of 95 % capacitance retention after 5000 charge‐discharge cycling. [ABSTRACT FROM AUTHOR]

We investigated the dynamics of carbonate system which was greatly modulated by a river plume and coastal upwelling in July 2014 and July 2015 at the east coast of Hainan Island where a fringing reef distributes inshore. By using a three end-member mixing model, we semiquantitatively estimated the removal of dissolved inorganic carbon (DIC) mediated by biological production in the river plume and upwelled water to be 13 ± 17 and 15 ± 16 μmol kg−1, respectively. The enhanced organic production was mainly responsible for these DIC consumptions in both two regimes, however, nearly a half of DIC removal was attributed to biocalcification in the plume system while it was negligible in the upwelling system. Furthermore, the modeled results over reefs revealed that river plume and coastal upwelling were two major threats of acidification to coral communities at the east coast of Hainan Island during cruises. In comparison, the biological contribution to acidification was limited for balancing between organic production and biocalcification during July 2014 cruise, whereas the acidification was greatly intensified by organic degradation during July 2015 cruise. It was verified that naturally local acidification (physical and biological processes) played a major role in great pH decreases on a short-term scale, leading to coastal waters more vulnerable to anthropogenic 'ocean acidification' (uptake of atmospheric CO2) by reducing buffering capacity of waters. Finally, effects of acidification associated with other local threats on a fringing reef were further depicted with a conceptual model. [ABSTRACT FROM AUTHOR]

ABSTRACT An uniformly distributed film consisting of polyaniline (PANI) nanoparticles and carboxylic acid functionalized multiwalled carbon nanotubes (MWNTs-COOH) was successfully assembled on ITO plates from a layer-by-layer (LBL) method by using electrostatic interactions as the main driving force. The good conjugation between PANI nanoparticles and MWNTs-COOH resulted in significant electrochemical performance variation of the obtained films. In addition, the assembled MWNT-COOH/PANI/ITO showed synergistic effect to the electrochemical oxidation of nifedipine (NIF) when used as a sensor. Compared with bare ITO, the oxidation potential of NIF can be decreased about 170 mV on MWNT-COOH/PANI/ITO, and the lower detection limit of NIF was as low as 1.0 × 10−6 mol/L. In addition, the assembled electrode gave no responses to interferences such as glucose, urea, ascorbic acid, and trisodium citrate, which showed high selectivity for recognition and quantification of NIF. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43452. [ABSTRACT FROM AUTHOR]

High-resolution pollen and charcoal records from Qinghai Lake in south-western China are presented. The records reveal variations in vegetation, fire and climate history since 18 500 cal a BP. The results show that seven significant vegetation changes are recorded, which are responses to climate changes and/or fire events. Frequent and intensive fires occurred during the periods 17 900-15 000, 13 000-11 500 and 4280-980 cal a BP, corresponding to relatively dry climatic conditions. Combined with the climatic record from Tiancai Lake, the regional climatic changes since 18 500 cal a BP in western Yunnan Province are reconstructed. Namely, the Heinrich Event 1, the Bølling-Allerød warm period and the Younger Dryas event during the last deglaciation are ubiquitous in western Yunnan Province. The start of the Holocene is recorded at 11 500 cal a BP. The Holocene climatic optimum occurred between 8450 and 4280 cal a BP. After 4280 cal a BP, the climate deteriorated, accompanied by evidence for human impact. Based on this study, we consider that vegetation and climatic changes since 18 500 cal a BP in south-western Yunnan Province are primarily driven by September and average summer solar insolation, with some associated influence from regional sea-surface temperature and sealevel rise. [ABSTRACT FROM AUTHOR]

ABSTRACT High electrochemical active free-standing multiwalled carbon nanotube (MWNT) films have been synthesized from aniline oligomer functionalized MWNTs (MWNT-AO), by using filtration of the acidic phosphate ester (APE) doped MWNT-AO dispersions. The homogeneously distributed MWNTs endowed APE/MWNT films automatically releasing from the filter membrane. The sheet resistivity of MWNT-AO (850 Ω sq−1) showed a lower value than that of carboxyl MWNTs (1273 Ω sq−1), due to the doping effect of MWNT on aniline oligomer, confirmed by the N1s X-ray photoelectron spectrum. However, it showed a higher sheet resistivity value of 1526 Ω sq−1 after further doped by APE, because of the presence of unreacted dopant. After removing the residual insulating dopant by the vacuum filtration, the resultant APE/MWNT films showed the sheet resistivity value as low as 131 Ω sq−1. Thermogravimetric analysis showed that the MWNT loading in the film can be over than 77%, which showed the specific capacitance as high as 249 F g−1. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40259. [ABSTRACT FROM AUTHOR]

C60/polyaniline (PANI) nanocomposites have been synthesized by the oxidative polymerization of aniline with ammonium peroxydisulfate in the presence of C60 by using an interfacial reaction. When compared with the pure PANI nanofibers from the similar process, the diameter of the obtained C60/PANI nanofibers was increased because of the encapsulation of C60 into PANI during aniline polymerization, which resulted from the charge-transfer interactions between C60 and aniline fragment in PANI. In addition, the resulting C60/PANI nanocomposites synthesized from the low initial C60/aniline molar ratio (less than 1:25) showed the homogenous morphology composed of fiber network structures, which has an electrical conductivity as high as 1.1 × 10−4 S/cm. However, the C60/PANI nanocomposites from the higher initial C60/aniline molar ratio (more than 1:15) showed the nonuniformly distributed morphology, and the electrical conductivity was decreased to 3.5 × 10−5 S/cm. Moreover, the C60/PANI nanocomposites from the interfacial reaction showed a higher value of electrical conductivity than the mechanically mixed C60/PANI blends with the same C60 content, because of the more evenly distributed microstructures. FTIR, UV-vis, and CV data confirmed the presence of C60 and the significant charge-transfer interactions in the resultant nanocomposites, which was responsible for the morphology development of the C60/PANI and the variation of the electrical conductivity. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 [ABSTRACT FROM AUTHOR]

Jin, Z. D., Bickle, M. J., Chapman, H. J., Yu, J., An, Z., Wang, S. & Greaves, M. J. 2010: Ostracod Mg/Sr/Ca and Sr/Sr geochemistry from Tibetan lake sediments: Implications for early to mid-Pleistocene Indian monsoon and catchment weathering. Boreas, 10.1111/j.1502-3885.2010.00184.x. ISSN 0300-9483 Lacustrine sediment serves as a valuable archive for tracing catchment weathering processes associated with past climatic and/or tectonic changes. High-resolution records of fossil ostracod Mg/Ca, Sr/Ca and Sr/Sr ratios from a lake sediment core from the central Tibetan Plateau reveal a temporal link between lake-water chemistry and catchment weathering and distinct monsoonal oscillations over the early to mid-Pleistocene. Between 2.01 and 0.95 Ma, lake-water chemistry was dominated by a high proportion of carbonate weathering related to variations in the Indian monsoon, resulting in relatively low and constant ostracod Sr/Sr but obvious fluctuations in Mg/Ca, Sr/Ca and δO. Across the mid-Pleistocene transition (MPT), a significant increase in Sr/Sr and frequently fluctuating ratios of ostracod Mg/Ca, Sr/Ca and δO are coincident with increases in both Chinese loess grain size and Arabian Sea lithogenic flux. This correlation indicates an increased glaciation and a strong monsoon seasonal contrast over the plateau. The increase in lake-water Sr/Sr across the MPT highlights a change in catchment weathering patterns, rather than one in climate-enhanced weathering intensity, with an increased weathering of Sr-rich minerals potentially induced by marked extensive glaciation and strong seasonality in the central plateau. [ABSTRACT FROM AUTHOR]

Because of the different geochemical behaviour of rubidium and strontium in earth surface processes, variations of the Rb/Sr ratios in lake sediments were used as a geochemical proxy of chemical weathering and past climate in a single watershed. Low magnetic susceptibility, low CaCO3, low Sr concentration and, hence, high Rb/Sr ratio in the lake sediments indicate weak chemical weathering under a cold but wet climate during the Little Ice Age (LIA) in the closed Daihai Lake watershed. The concordant change in both Sr and CaCO3 concentrations with Delta18O values in the Dunde ice core suggests that weak chemical weathering during the wet LIA was controlled by air temperature. After the LIA, however, precipitation played a dominant role in chemical weathering. [ABSTRACT FROM AUTHOR]