Ethylene epoxidation is industrially and commercially one of the most important selective oxidations. Silver catalysts have been state-of-the-art for decades, their efficiency steadily improving with empirical discoveries of dopants and co-catalysts. Herein, we perform a computational screening of the metals in the periodic table, identify prospective superior catalysts and experimentally demonstrate that Ag/CuPb, Ag/CuCd and Ag/CuTl outperform the pure-Ag catalysts, while they still confer an easily scalable synthesis protocol. Furthermore, we show that to harness the potential of computationally-led discovery of catalysts fully, it is essential to include the relevant in situ conditions e.g., surface oxidation, parasitic side reactions and ethylene epoxide decomposition, as neglecting such effects leads to erroneous predictions. We combine ab initio calculations, scaling relations, and rigorous reactor microkinetic modelling, which goes beyond conventional simplified steady-state or rate-determining modelling on immutable catalyst surfaces. The modelling insights have enabled us to both synthesise novel catalysts and theoretically understand experimental findings, thus, bridging the gap between first-principles simulations and industrial applications. We show that the computational catalyst design can be easily extended to include larger reaction networks and other effects, such as surface oxidations. The feasibility was confirmed by experimental agreement.
The rapid expansion of the Slavic speakers in the second half of the first millennium CE remains a controversial topic in archaeology, and academic passions on the issue have long run high. Currently, there are three main hypotheses for this expansion. The aim of this paper was to test the so-called "hybrid hypothesis," which states that the movement of people, cultural diffusion and language diffusion all occurred simultaneously. For this purpose, we examined an archaeological Deep Data set with a machine learning method termed time series clustering and with emerging hot spot analysis. The latter required two archaeology-specific modifications: The archaeological trend map and the multiscale emerging hot spot analysis. As a result, we were able to detect two migrations in the Eastern Alps between c. 500 and c. 700 CE. Based on the convergence of evidence from archaeology, linguistics, and population genetics, we have identified the migrants as Alpine Slavs, i.e., people who spoke Slavic and shared specific common ancestry.
The elderly are vulnerable and potentially unpredictable active participants in traffic who deserve special attention. Longer life expectancy entails a greater number of senior drivers, that is, persons with various health problems and difficulties accompanying old age. At the turn of the millennium, the share of population aged 65 or more in Slovenia was around 13%, and in 25 years it will be near as much as 19%. The share of drivers from this age group was 28% a year ago, and it is expected to reach about 54%. Numerous studies have shown that there are many differences in driving attitude between the young and the elderly. The young are by large active victims, and their main offense and cause of accident is speeding, while the elderly are more passive and their main offense is ignoring and enforcing the right of way. This paper focuses on the differences in the occurrence and type of injuries between the young and the elderly drivers, based on an analysis of all road accidents in Slovenia in the period between 1998-2000. Older people (over 65) caused only 4.7% of all road accidents (16.7% of all accidents involving pedestrians, 11.5% of all involving cyclists, 2.7% involving motorcyclists and 5% of all accidents involving car drivers). Of all accidents, 89.3% were without injuries, and the fatal outcome was registered in 0.4% accidents. Among the elderly (65-74 years of age), however, this share was 1%, and rising to 2.7% with the age 75 and above. By calculating the weight index, which discriminates between minor and severe injuries, and the fatal outcome, it was established that age groups 65-74 and > or = 75 cause three and five times greater damage, respectively than age groups from 18 to 54 years. With years, psychophysical changes lead to a drop in driving ability, which in turn increases the risk of road accidents. It is true that elderly people cause less traffic accidents (and also drive less) than the young, but when they are involved in an accident, as a rule the consequences are more tragical. A research of this increasing group traffic participants (in the role of drivers as well) could provide an important contribution to their safety and to the safety of all people involved in road traffic.
Children with special pathology, such as clefts and scoliosis, must be managed at a special centre until a comprehensive treatment strategy has been developed and appropriate therapeutic measures undertaken. Examinations were performed in 375 children, who were then distributed into three groups: patients with clefts (group A), scoliosis (group B) and no special pathology (group C). Monomaxillary therapy was used most frequently in the group with clefts and bimaxillary therapy in the group with scoliosis. In patients with scoliosis extractions of permanent teeth should be avoided in order to preserve a maximum number of occlusal units, since they transmit forces from the brace to the skull, especially during sleep. Groups A and C revealed an increase in the number of adults, including new patients and patients who resumed treatment after it had been interrupted. These patients are very cooperative and the results of corrective treatment are extremely favourable.
Scientists have proposed a new method for finding tightly bound supermassive black hole pairs by searching for stars that flash repeatedly as their light is magnified by the black holes’ gravity。 The timing and brightness of these bursts could provide a unique fingerprint of black holes slowly spiraling toward a future collision
Use-after-free bug can be exploited to evade sandbox defenses
Researchers have developed a compact quantum detector that makes terahertz radiation much easier to detect。 A specially designed metasurface funnels incoming energy into tiny active regions, greatly strengthening the electrical signal produced。 The approach boosted efficiency by roughly 20 times compared to earlier designs and could pave the way fo
NASA’s Roman Space Telescope could revolutionize the search for alien worlds by discovering around 100,000 exoplanets—far more than all previous missions combined。 It will look deep into unexplored parts of the Milky Way, helping scientists compare planetary systems across very different galactic environments。 The mission will also uncover rare Ear
A team at the University of Chicago has discovered a surprisingly simple way to create powerful quantum states that are normally difficult to produce。 By making small adjustments to the energy levels of atoms inside an optical cavity, researchers can generate a wide variety of highly entangled states without adding complicated hardware
Scientists have created a tiny chip that can generate, steer, and read light-based information all in one device, marking a major leap toward ultra-fast, energy-efficient computing。 The breakthrough uses atomically thin materials and nanoscale structures to control a unique quantum property of light called the “valley” degree of freedom, allowing i
Scientists have uncovered unexpected quantum complexity inside cobalt, a metal long thought to be fully understood。 Advanced measurements revealed a dense network of topological electronic states that remain robust at room temperature。 These states enable extremely fast electron behavior and can be switched or controlled using magnetism
Researchers discovered a way to reverse the direction of energy flow in turbulence, challenging a theory that has stood for more than 80 years。 The finding could open new possibilities for controlling ocean currents, improving medical technologies, and enhancing climate forecasting
Scientists have successfully tested an AI-designed universal coronavirus vaccine in humans for the first time, finding it to be safe and well tolerated。 The vaccine generated immune responses against multiple coronaviruses, including SARS-CoV-2, SARS, and related bat viruses with pandemic potential。 By targeting features shared across an entire vir
A lightweight new X-ray telescope could finally give scientists something they’ve never had before: a complete chemical map of the Moon。 Researchers used detailed mission simulations to show that a compact telescope orbiting the Moon could identify key elements across the entire lunar surface, helping reveal how the Moon formed and evolved
Scientists at Lawrence Livermore National Laboratory recreated part of the intense chaos inside a nuclear fireball to better understand how radioactive fallout forms。 Their experiments revealed that the way vaporized materials cool can dramatically change the particles that eventually form, especially for volatile elements like cesium