graphitic electrode. [ 8 ] Unfortunately, when applied in a dualgraphite battery, the EC molecules in the electrolyte can bind tightly with PF 6 − anions, and prevent the intercalation of these anions into the interlayer spaces of graphite positive electrodes. [ 9 ] Recently, with the developments of novel electrolyte formulas, several studies have reported signifi cantly improved reversibility of dual-carbon batteries. [ 10 ] Read et al. reported a reversible dual-graphite battery with simultaneous accommodation of Li + and PF 6 − in graphitic structures enabled by a high voltage electrolyte based on fl uorinated solvent and additive. [ 10a ] The battery demonstrated a reversible capacity of 60 mAh g −1 and a capacity retention of 62% after 50 cycles at C/7 rate. Rothermel et al. reported a dual-graphite battery based on a mixture of lithium bis-(trifl uoromethanesulfonyl)-imide (LiTFSI) and ionic liquid with SEI-forming additive. This electrolyte formula not only enabled stable TFSI − intercalation into the graphite positive electrode, but also allowed highly reversible intercalation of Li + into the graphite negative electrode. [ 10b ] Under an upper cut-off potential of 5.0 V, the full graphite battery presented a capacity of 97 mAh g −1 at a current rate of 10 mA g −1 , and 50 mAh g −1 at 500 mA g −1 , which shed light on the potential application of dual-ion batteries as an environmentally friendly energy storage technology.Herein, we report a novel aluminum-graphite dual-ion battery (AGDIB) in an ethyl-methyl carbonate (EMC) electrolyte with high reversibility and high energy density. It is the fi rst report on using an aluminum anode in dual-ion battery. The battery shows good reversibility, delivering a capacity of ≈100 mAh g −1 and capacity retention of 88% after 200 chargedischarge cycles at 2 C (1 C corresponding to 100 mA g −1 ). To the best of our knowledge, performance of the battery is among the best of reported dual-ion batteries.Figure 1 a schematically illustrates the initial and charged states of the AGDIB. Upon charging, PF 6 − anions in the electrolyte intercalate into the graphite cathode, while the Li + ions in the electrolyte deposit onto the aluminum counter electrode to form an Al-Li alloy. The discharge process is the reverse of the charge process, where both PF 6 − anions and Li + ions diffuse back into the electrolyte. The Al counter electrode acts as both the anode and the current collector, which greatly benefi ts the specifi c energy density and volumic energy density of the AGDIB. [ 11 ] Figure 1 b shows galvanostatic charge-discharge curves of the AGDIB, exhibiting a typical profi le of anion intercalation/deintercalation into/from graphite. The charge curve is mainly composed of three regions between 4.08 and 4.59 V (stage III), 4.59 and 4.63 V (stage II), and 4.63 and 5.0 V (stage I), each region corresponds to an anion intercalation stage of graphite, according to previous reports. [ 6e ] A dQ/dV differential curve of the battery is shown in the inset of Figure 1 b. Pe...

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In this work, combining both advantages of potassium-ion batteries and dual-ion batteries, a novel potassium-ion-based dual-ion battery (named as K-DIB) system is developed based on a potassium-ion electrolyte, using metal foil (Sn, Pb, K, or Na) as anode and expanded graphite as cathode. When using Sn foil as the anode, the K-DIB presents a high reversible capacity of 66 mAh g at a current density of 50 mA g over the voltage window of 3.0-5.0 V, and exhibits excellent long-term cycling performance with 93% capacity retention for 300 cycles. Moreover, as the Sn foil simultaneously acts as the anode material and the current collector, dead load and dead volume of the battery can be greatly reduced, thus the energy density of the K-DIB is further improved. It delivers a high energy density of 155 Wh kg at a power density of 116 W kg , which is comparable with commercial lithium-ion batteries. Thus, with the advantages of environmentally friendly, cost effective, and high energy density, this K-DIB shows attractive potential for future energy storage application.

Past global climate changes had strong regional expression. To elucidate their spatio-temporal pattern, we reconstructed past temperatures for seven continental-scale regions during the past one to two millennia. The most coherent feature in nearly all of the regional temperature reconstructions is a long-term cooling trend, which ended late in the nineteenth century. At multi-decadal to centennial scales, temperature variability shows distinctly different regional patterns, with more similarity within each hemisphere than between them. There were no globally synchronous multi-decadal warm or cold intervals that define a worldwide Medieval Warm Period or Little Ice Age, but all reconstructions show generally cold conditions between AD 1580 and 1880, punctuated in some regions by warm decades during the eighteenth century. The transition to these colder conditions occurred earlier in the Arctic, Europe and Asia than in North America or the Southern Hemisphere regions. Recent warming reversed the long-term cooling; during the period AD 1971-2000, the area-weighted average reconstructed temperature was higher than any other time in nearly 1,400 years

SummaryLianas exhibit peak abundance in tropical forests with strong seasonal droughts, the ecophysiological mechanisms associated with lianas coping with water deficits are poorly understood.We examined soil water partitioning, sap flow, and canopy eco-physiological properties for 99 individuals of 15 liana and 34 co-occurring tree species in three tropical forests that differed in soil water availability.In the dry season, lianas used a higher proportion of deep soil water in the karst forest (KF; an area with severe seasonal soil water deficit (SSWD)) and in the tropical seasonal forest (TSF, moderate SSWD), permitting them to maintain a comparable leaf water status than trees in the TSF or a better status than trees in the KF. Lianas exhibited strong stomatal control to maximize carbon fixation while minimizing dry season water loss. During the dry period, lianas significantly decreased water consumption in the TSF and the KF. Additionally, lianas had a much higher maximum photosynthetic rates and sap flux density in the wet season and a lower proportional decline in photosynthesis in the dry season compared with those of trees.Our results indicated that access to deep soil water and strong physiological adjustments in the dry season together with active wet-season photosynthesis may explain the high abundance of lianas in seasonally dry forests.

A 3D porous Al foil coated with a uniform carbon layer (pAl/C) is prepared and used as the anode and current collector in a dual-ion battery (DIB). The pAl/C-graphite DIB demonstrates superior cycling stability and high rate performance, achieving a highly reversible capacity of 93 mAh g after 1000 cycles at 2 C over the voltage range of 3.0-4.95 V. In addition, the DIB could achieve an energy density of ≈204 Wh kg at a high power density of 3084 W kg .

Summary1. Stem xylem characteristics have a great impact on growth and adult stature of trees because of their role in mechanical support, long-distance water transport and whole-plant carbon allocation. Yet, despite the potential causal link between xylem traits and plant growth ⁄ adult stature, most studies have tried to link wood density, an indirect but easy to measure proxy for wood properties, to tree growth and size. 2. To determine whether xylem traits outperform wood density as predictors of tree growth and stature, we evaluated the covariation among wood density, xylem anatomical traits, tree diameter growth rate and adult stature in 40 Asian tropical tree species through principal component analyses and through bivariate correlation, both across species and across phylogenetically independent contrasts. 3. Vessel diameter exhibited a tight negative relationship with vessel frequency. Wood density showed a significant correlation with vessel diameter and density, but not with vessel fraction. Most correlations between functional traits indicate adaptive coordination, demonstrated by significant correlations between phylogenetically independent contrasts. 4. Across species, diameter growth rate and adult stature were positively correlated with vessel lumen diameter and potential hydraulic conductivity, but not with wood density. Thus, our results suggest that xylem anatomical traits that are linked to hydraulic conductivity are better predictors of tree growth rate and adult stature than wood density. 5. Synthesis. We found that xylem anatomical traits have a more significant influence on wholeplant performance due to their direct association with stem hydraulic conductivity, whereas wood density is decoupled from hydraulic function due to complex variations in xylem components.

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