Hasil untuk "Organic chemistry"

M. Hopkinson, C. Richter, M. Schedler et al.

Jiang Wang, María Sánchez-Roselló, J. Aceña et al.

Filip Ilievski, Aaron D. Mazzeo, R. Shepherd et al.

The development of new types of soft robots, and especially of materials and methods for the fabrication of this class of robots, requires and offers rich new opportunities for interdisciplinary research involving organic chemistry, soft materials science, and robotics. This paper describes a methodology based on embedded pneumatic networks (PneuNets) that enables large-amplitude actuations in soft elastomers by pressurizing embedded channels. Examples include a structure that can change its curvature from convex to concave, and two devices that act as compliant grippers for handling fragile objects (e.g., an uncooked chicken egg, a live, anesthetized mouse) without damaging either. These systems suggest new areas of research for organic materials that are relevant to soft robotics, and to which chemists can make important contributions.

Lizeng Gao, Jie Zhuang, L. Nie et al.

J. R.

N. Turro

B. Giepmans, S. Adams, Mark Ellisman et al.

W. Saenger

C. Appelo, D. Postma

W. Xie, Zongming Gao, W. Pan et al.

M. Nishio

P. Frémont, N. Marion, S. Nolan

C. R. Becer, R. Hoogenboom, Ulrich S. Schubert et al.

J. Hachmann, R. Olivares-Amaya, Sule Atahan-Evrenk et al.

P. Campbell, Adam J. V. Marwitz, Shih‐Yuan Liu

J. Kroll, N. Ng, S. Murphy et al.

Seda Keskin, S. Kızılel

Charlie Fynn Perkins, Marcus Webb, Fred J. Currell

Understanding the spatio-temporal evolution of radiolytic species created by high-energy electrons in water underpins key applications from radiotherapy and nuclear safety to environmental processing and electron microscopy. Here, using the Manchester Inhomogeneous Radiation Chemistry by Linear Expansions (MIRaCLE) toolkit, we introduce and benchmark a novel approach to simulating these processes. Although the initial conditions are determined stochastically, the subsequent time evolution is calculated deterministically using a continuum representation, derived from those initial conditions. This hybrid approach essentially averages over many chemistry ``trajectories'' simultaneously, often converging to the 1% level in one shot, not requiring multiple runs. We demonstrate this new approach through the calculation of time-dependent G-values for e_{aq}^-$, \dot{\mathrm{OH}} and other radiolytic products, including at unprecedented dose rates where calculations which would take years with a conventional Monte Carlo approach can be performed in mere hours on a commercial laptop. We demonstrate that the main artifact of continuum modelling can be mitigated by a correction term. These results establish MIRaCLE as a flexible and efficient platform for modelling long-timescale radiolysis, providing a bridge between Monte Carlo approaches and macroscopic reaction--diffusion schemes, with broad implications for radiation chemistry in medicine, energy, and materials science.

T. Benest Couzinou, A. Amsler Moulanier, O. Mousis

Complex organic molecules are key markers of molecular diversity, and their formation conditions in protoplanetary disks remain an active area of research. These molecules have been detected on a variety of celestial bodies, including icy moons, and may play a crucial role in shaping the current composition of the Galilean moons. Experimental studies suggest that their formation could result from UV irradiation or thermal processing of NH3:CO2 ices. In this context, we investigate the formation of complex organic molecules in the protosolar nebula and their subsequent transport to the Jupiter system region. Lagrangian transport and irradiation simulations of 500 individual particles are performed using a two-dimensional disk evolution model. Based on experiments with UV irradiation and thermal processing of CO2:NH3 ice, this model allows us to estimate the estimate the potential for the formation of complex organic molecules through these processes. Almost none of the particles released at a local temperature of 20 K (corresponding to ~12 AU from the Sun) reach the location of the system of Jupiter. However, when released at a local temperature of 80 K (~7 AU), approximately 45% of the centimetric particles and 30% of the micrometric particles can form complex organic molecules via thermal processing, subsequently reaching the location of the system of Jupiter within 300 kyr. Assuming that the Galilean moons formed in a cold circumplanetary disk around Jupiter, the nitrogen-bearing species potentially present in their interiors could have originated from the formation of complex organic molecules in the protosolar nebula.

Sara Gil-Guerrero, Nicolás Ramos-Berdullas, Marcos Mandado

The design of nanoscale electronic components remains a major challenge because we have limited control over the chemical and physical properties of their molecular constituents. Even subtle structural or compositional modifications can significantly alter their electronic behavior. Consequently, updating a molecular component often necessitates developing a new model from scratch. In this study, we present a comprehensive analysis of the rectification properties of a promising molecular diode initially proposed by Aviram and Van Dyck. The model has been systematically decomposed into fundamental building blocks, enabling the electron transport process to be examined both as an integrated event and as a sum of cooperative interactions. Our findings reveal that certain motifs—such as the D-σ-A architecture—play a significant role in rectification. However, achieving high-performance molecular rectifiers also requires cooperative interplay with other structural elements that contribute to rectification, such as asymmetric molecule–metal contacts. In this study, we conduct a detailed investigation of the roles these elements play in shaping the rectifying characteristics, and we further interpret their effects by analyzing the dominant transport channels under forward and backward bias conditions. This deeper understanding of the transport mechanism offers greater control over the system and opens the door for rational design strategies for improving rectification efficiency in future molecular devices.