Inhibiting the phase transition of WO_(3)for highly stable aqueous electrochromic battery

Aqueous electrochromic battery(ECB)has shown intense potential for achieving energy storage and saving simultaneously.While tungsten oxide(WO_(3))is the most promising EC material for commercialization,the cycling stability of WO_(3)-based aqueous ECBs is currently unsatisfactory due to the repeated phase transition during the redox process and the corrosion by acidic electrolytes.Herein,we present a titanium-tungsten oxide alloy(Ti-WO_(3))with controllable morphology and crystal phase synthesized by a facile hot injection method to overcome the challenges.In contrast to conventional monoclinic WO_(3),the Ti-WO_(3)nanorods can stably maintain their cubic crystal phase during the redox reaction in an acidic electrolyte,thus leading to dramatically enhanced response speed and cycling stability,Specifically,when working in a well-matched hybrid Al^(3+)/Zn^(2+)aqueous electrolyte,our phasetransition-free cubic Ti-WO_(3)exhibits an ultra-high cycling stability(>20000 cycles),fast response speed(3,95 s/4,65 s for bleaching/coloring),as well as excellent discharge areal capacity of 214.5 mA h m^(-2),We further fabricate a fully complementa ry aqueous electrochromic device,for the first time,using a Ti-WO_(3)/Prussian blue device architecture.Remarkably,the complementary ECB shows>10000 stable operation cycles,attesting to the feasibility of our Ti-WO_(3)for practical applications.Our work validates the significance of inhibiting the phase transitions of WO_(3)during the electrochromic process for realizing highly cyclable aqueous ECB,which can possibly provide a generalized design guidance for other high-quality metallic oxides for electrochemical applications.

Competition between anthocyanin and kaempferol glycosides biosynthesis affects pollen tube growth and seed set of Malus

Flavonoids play important roles in regulating plant growth and development.In this study,three kaempferol 3-O-glycosides were identi fi ed and mainly accumulated in fl owers but not in leaves or fruits of Malus.In Malus,fl ower petal color is normally white,but some genotypes have red fl owers containing anthocyanin.Anthocyanin biosynthesis appears to be in competition with kaempferol 3-O-glycosides production and controlled by the biosynthetic genes.The white fl ower Malus genotypes had better-developed seeds than the red fl ower genotypes.In fl owers,the overexpression of MYB10 in Malus domestica enhanced the accumulation of anthocyanin,but decreased that of kaempferol 3-O-glycosides.After pollination the transgenic plants showed slower pollen tube growth and fewer developed seeds.Exogenous application ofdifferent fl avonoid compounds suggested that kaempferol 3-O-glycosides,especially kaempferol 3-O-rhamnoside,regulated pollen tube growth and seed set rather than cyanidin or quercetin 3-O-glycosides.It was found that kaempferol 3-O-rhamnoside might regulate pollen tube growth through effects on auxin,the Rho of plants(ROP)GTPases,calcium and the phosphoinositides signaling pathway.With the inhibition of auxin transport,the transcription levels of Heat Shock Proteins(HSPs)and ROP GTPases were downregulated while the levels were not changed or even enhanced when blocking calcium signaling,suggesting that HSPs and ROP GTPases were downstream of auxin signaling,but upstream of calcium signaling.In summary,kaempferol glycoside concentrations in pistils correlated with auxin transport,the transcription of HSPs and ROP GTPases,and calcium signaling in pollen tubes,culminating in changes to pollen tube growth and seed set.

Bioaccumulation, subcellular distribution and chemical forms of yttrium in rice seedling

Yttrium（Y） accumulation in soil is a serious environment problem in China. To understand the mechanisms involved in Y tolerance and detoxification in rice seedling, the bioaccumulation, subcellular distribution, and chemical forms of Y was investigated in the present study. The results show that the content of Y both in roots and shoots increases with the increasing concentration of Y, and a large amount of Y is stored in roots. Subcellular distribution of Y in rice indicates that the majority of Y is bound to cell wall. Meanwhile, various chemical forms of Y is absorbed by rice. The greatest amount of Y is extracted by 2% hydrate acetic acid（HAc） and 0.6 mol/L HCl（particularly 2% HAc）, which indicates that most of Y is combined with un-dissolved phosphate and oxalate（particularly phosphate）. Cluster analysis, based on Y abundance levels, reveals the relationship between Y distribution patterns and chemical forms. Our results imply that Y forming of precipitates with phosphate（and/or oxalate） and depositing in the cell wall may be a key strategy for Y detoxicity and tolerance in rice.

Regulation mechanism for the formation and microwave absorbing performance of CNT/CoFe-MOF derived hierarchical composite

The structure design,performance analysis,and process optimization of CNT/MOF-derived hierarchical composite play an important role in the development of high-performance microwave absorbing materi-als.Herein,the preparation,morphology evolution,and electromag-netic wave absorption mechanism of CNT/MOF-derived hierarchical composite were systematically investigated.The regulation mechan-ism was revealed by studying the changes in the morphological characteristics,electromagnetic properties,and microwave absorbing performance of CNT/MOF-derived hierarchical composite under differ-ent process parameters.The results show that the morphological characteristics and interface bonding between CNT and MOF have a great impact on the absorptive capacity.The composite with com-position of 0.28Co/0.26Fe has a maximum absorption of−46 dB at 8.6 GHz and a thickness of 4 mm.In addition,the absorption band with reflection loss values of less than−20 dB can be operated with this thickness between 7.15 and 10.18 GHz,showing excellent absorbing ability and electromagnetic wave bandwidth.The regulation mechan-ism of CNT/MOF-derived hierarchical composite mainly depends on the effect of Lorentz force,the ion disorder of CoO-Fe_(2)O_(3) heterojunc-tion,and the spin polarization mechanism of free electrons.This study further improves the corresponding theoretical basis and new design principles,which provides technical support for the development of high-performance absorbing materials.