Electrochemical reduction of carbon dioxide is 草女人感觉a burgeoning field of research because the reaction presents an environmentally sustainable means of using the greenhouse gas as a feedstock. Optimal electrode design would maximize the efficiency of gas transport to the catalyst, but a persistent problem has been clogging over time due to precipitation of bicarbonate salts. Hao et al. found that introducing a small amount of volatile acid into the carbon dioxide input stream can prevent this salt precipitation and promote continuous reduction for up to 4500 hours.。
Evolutionary-scale enzymology enables exploration of a rugged catalytic landscape。
进化标准酶学助力探究杂乱催化景象。
▲ 作者：DUNCAN F. MUIR, GARRISON P. R. ASPER, PASCAL NOTIN, JACOB A. POSNER, DEBORA S. MARKS, MICHAEL J. KEISER, AND MARGAUX M. PINNEY。
The catalytic activity of a particular enzyme can vary widely between orthologs in different species, depending on their environment and specific metabolic needs. But how do such differences evolve and relate to specific structural features? Using a high-throughput microfluidic system, Muir et al. assayed nearly 200 orthologs of the enzyme adenylate kinase and used the resulting data to build a landscape view of catalytic activity. There was minimal correlation between growth temperature and activity, and high activity peaks were widely distributed in the landscape and likely evolved independently. Current protein language models group enzymes by structure but fail in predicting the catalytic activity landscape; however, there is potential to train models using experimental activity data.。
物理学Physics。
Gate-driven band modulation hyperdoping for high-performance p-type 2D semiconductor transistors。
Band alignment effects enable high levels of hole doping in a tungsten diselenide bilayer through its transfer of electrons into an adjacent tin disulfide monolayer. Ion implantation is often used to dope in semiconductor films, but this is difficult in few-layer transition metal dichalcogenides. Zhao et al. show that tuning of the band offset and charge transfer across the van der Waals interface with an external gate bias can produce a hole density of 1.49 × 10。14。per square centimeter, which is about five times the conventional dielectric limit.。
Differential absorption of circularly polarized light by a centrosymmetric crystal。
中心对称晶体对圆偏振光的差分吸收。
▲ 作者：KATHERINE A. PARRISH, ANDREW SALIJ, KENDALL R. KAMP, EVAN SMITH, AND ROEL TEMPELAAR。
Crystalline solids are governed by universal structure-property relationships derived from their crystal symmetry, leading to paradigmatic rules on what properties they can and cannot exhibit. A long-held structure-property relationship is that centrosymmetric crystals cannot differentially absorb circularly polarized light. In this study, we demonstrate the design, synthesis, and characterization of the centrosymmetric material Li。2。Co。3。（SeO。3。）。4。, which violates this relationship not by defying symmetry-imposed selection rules but by invoking a photophysical process not previously characterized for crystalline solids. This process originates from an interference between linear dichroism and linear birefringence, referred to as LD-LB, and involves strong chiroptical signals that invert upon sample flipping. In addition to enabling a chiroptical response under centrosymmetry, this process opens up photonic engineering opportunities based on crystalline solids.。
生态学Ecology。
Global importance of nitrogen fixation across inland and coastal waters。
内陆与滨海水域固氮效果的全球重要性。
▲ 作者：ROBINSON W. FULWEILER, SHELBY RINEHART, JASON TAYLOR, MICHELLE C. KELLY, MEGAN E. BERBERICH, NICHOLAS E. RAY, AUTUMN OCZKOWSKI, SAWYER BALINT, MAR BENAVIDES, AND AMY M. MARCARELLI。
Biological nitrogen fixation, which converts nitrogen gas into biologically available fixed nitrogen, has been studied extensively in terrestrial and open ocean systems, but less is known about this process in inland and coastal waters. Fulweiler et al. found that inland and coastal regions fix nitrogen at prodigious rates. Although these habitats occupy less than 10% of Earth’s surface, they are responsible for approximately 20% of the nitrogen fixation occurring on land and in the ocean.。
Observed trend in Earth energy imbalance may provide a constraint for low climate sensitivity models。
地球能量失衡的观测趋势可为低气候敏感性模型供给束缚。
▲ 作者：GUNNAR MYHRE, IVIND HODNEBROG, NORMAN LOEB , AND PIERS M. FORSTER。
Climate warms or cools depending on whether the net energy flux from incoming solar radiation is respectively greater or less than that of outgoing long-wave radiation at the top of Earth’s atmosphere. Satellite data have shown that an energy imbalance producing warming has strengthened between 2001 and 2023. Myhre et al. show that climate models with low climate sensitivity do not reproduce that trend in Earth energy imbalance. Their finding means that increasing concentrations of atmospheric greenhouse gases likely will cause even more warming than most current models predict.。
