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Lithium–sulfur batteries (LSBs) can work at high temperatures, but they suffer from poor cycle life stability due to the “shuttle effect” of polysulfides. In this study, pollen‐derived porous carbon/cuprous phosphide (PC/Cu3P) hybrids were rationally synthesized using a one‐step carbonization method using pollen as the source material, acting as the sulfur host for LSBs. In the hybrid, polar Cu3P can markedly inhibit the “shuttle effect” by regulating the adsorption ability toward polysulfides, as confirmed by theoretical calculations and experimental tests. As an example, the camellia pollen porous carbon (CPC)/Cu3P/S electrode shows a high capacity of 1205.6 mAh g−1 at 0.1 C, an ultralow capacity decay rate of 0.038% per cycle after 1000 cycles at 1 C, and a rather high initial Coulombic efficiency of 98.5%. The CPC/Cu3P LSBs can work well at high temperatures, having a high capacity of 545.9 mAh g−1 at 1 C even at 150°C. The strategy of the PC/Cu3P hybrid proposed in this study is expected to be an ideal cathode for ultrastable high‐temperature LSBs. We believe that this strategy is universal and worthy of in‐depth development for the next generation energy storage devices. We demonstrate a strategy of a pollen‐derived porous carbon (PC)/Cu3P hybrid to load sulfur as a cathode for advanced lithium–sulfur batteries (LSBs). It is known that Cu3P can inhibit the shuttle effect by regulating polysulfide adsorption ability. The PC/Cu3P hybrid is effective for various kinds of pollens. As an example, the camellia pollen porous carbon (CPC)/Cu3P/S electrode shows a high capacity of 1205.6 mAh g−1 at 0.1 C, an ultralow capacity decay rate of 0.038% per cycle after 1000 cycles at 1 C, and a high initial Coulombic efficiency of 98.5%. The CPC/Cu3P LSBs can work well at high temperatures, having a low capacity decay rate of 0.061% per cycle after 1000 cycles at 1 C at 100°C and a high initial capacity of 545.9 mAh g−1 at 1 C even at 150°C. The PC/Cu3P hybrid is confirmed to be a universal strategy for the manufacture of ultrastable high‐temperature LSBs.

Nanotechnologies are increasingly being developed for medical purposes. However, these nanomaterials require ultrastability for better control of their pharmacokinetics. The present study describes three types of ultrastable gold nanoparticles stabilized by thiolated polyethylene glycol groups remaining intact when subjected to some of the harshest conditions described thus far in the literature, such as autoclave sterilization, heat and freeze-drying cycles, salts exposure, and ultracentrifugation. Their stability is characterized by transmission electron microscopy, UV-visible spectroscopy, and dynamic light scattering. For comparison purposes, two conventional nanoparticle types were used to assess their colloidal stability under all conditions. The ability of ultrastable gold nanoparticles to encapsulate bimatoprost, a drug for glaucoma treatment, is demonstrated. MTS assays on human corneal epithelial cells is assessed without changing cell viability. The impact of ultrastable gold nanoparticles on wound healing dynamics is assessed on tissue engineered corneas. These results highlight the potential of ultrastable gold nanoparticles as a drug delivery system in ocular therapy.

Metal-organic frameworks (MOFs) are attractive for promising applications but plagued by difficult recovery and deployment due to their intrinsic nano/micro powder nature. Although significant efforts have been made to develop separable solid matrixes for MOF supporting, the poor loading stability and durability of MOFs still challenge their engineering applications. Here, we present a facile and effective approach to fabricate MOF-based melamine foams (MFs) (denoted as MOFiths) with ultrahigh loading stability and operation stability, easy separation, and high-efficient performance for versatile robust applications. By adopting our approach, numbers of typical fragile MOFs characterized with wide ranges of particle size (from ∼ nm to ∼ µm) can be precisely incorporated into MFs with controllable loading ratios (up to ∼ 1,600%). Particularly, the produced MOFiths show excellent capacities for the highly effective and durable water purifications and acetalization reactions. 100% of organic pollutants can be rapidly destructed within 10 min by MOFiths initiated Fenton or catalytic ozonation processes under five successive cycles while the maximum adsorption capacity of MOFiths toward Pb(II), Cd(II), and Cu(II) reaches to 422, 222, and 105 mg·g −1 , respectively. This study provides a critical solution to substantially facilitate the engineering applications of MOFs for long-term use in practice.

Some predictions of the recently proposed theory of long-distance water transport in plants (the Compensating Pressure Theory) have been verified experimentally in sunflower leaves. The xylem sap cavitates early in the day under quite small water stress, and the compensating pressure P (applied as the tissue pressure of turgid cells) pushes water into embolized vessels, refilling them during active transpiration. The water potential, as measured by the pressure chamber or psychrometer, is not a measure of the pressure in the xylem, but (as predicted by the theory) a measure of the compensating pressure P. As transpiration increases, P is increased to provide more rapid embolism repair. In many leaf petioles this increase in P is achieved by the hydrolysis of starch in the starch sheath to soluble sugars. At night P falls, as starch is reformed. A hypothesis is proposed to explain these observations by pressure-driven reverse osmosis of water from the ground parenchyma of the petiole. Similar processes occur in roots and are manifested as root pressure. The theory requires a pump to transfer water from the soil into the root xylem. A mechanism is proposed by which this pump may function, in which the endodermis acts as a one-way valve and a pressure-confining barriers Rays and xylem parenchyma of wood act like the xylem parenchyma of petioles and roots to repair embolisms in trees. The postulated root pump permits a re-appraisal of the work done by evaporation during transpiration, leading to the proposal that in tall trees there is no hydrostatic gradient to be overcome in lifting water. Some published observations are re-interpreted in terms of the theory: doubt is cast on the validity of measurements of hydraulic conductance of wood; vulnerability curves are found not to measure the cavitation threshold of water in the xylem, but the osmotic pressure of the xylem parenchyma; if measures of xylem pressure and of hydraulic conductance are both suspect, the accepted view of the hydraulic architecture of trees needs drastic revision; observations that xylem feeding insects feed faster as the water potential becomes more negative are m accord with the theory; tyloses, which have been shown to form in vessels especially vulnerable to cavitation, are seen as necessary for the maintenance of P, and to conserve the supplementary refilling water Far from being a metastable system on the edge of disaster, the water transport system of the xylem is ultrastable: robust and self-sustaining in response to many kinds of stress.