Visible colorimetric dosimetry of UV and ionizing radiations by a dual-module photochromic nanocluster

Radiation dosimeters displaying conspicuous response of irradiance are highly desirable, owing to the growing demand of monitoring high-energy radiation and environmental exposure. Herein, we present a case of dosimetry based on a discrete nanocluster, [Th6(OH)4(O)4(H2O)6](TPC)8(HCOO)4∙4DMF∙H2O (Th-SINAP-100), by judiciously incorporating heavy Th6 polynuclear centers as radiation attenuator and organic linkers as photo-responsive sensor. Interestingly, dual-module photochromic transitions upon multiple external stimuli including UV, β-ray, and γ-ray are integrated into this single material. The striking color change, and more significantly, the visible color transition of luminescence in response to accumulating radiation dose allow an on-site quantitative platform for naked-eye detection of ionization radiations over a broad range (1–80 kGy). Single crystal X-ray diffraction and density functional theory calculations reveal that the dual-module photochromism can be attributed to the π(TPC) → π*(TPC) intermolecular charge transfer driven by enhanced π-π stacking interaction between the adjacent TPC moieties upon irradiation.

McKay matrices for finite-dimensional Hopf algebras

For a finite-dimensional Hopf algebra $\mathsf {A}$ , the McKay matrix $\mathsf {M}_{\mathsf {V}}$ of an $\mathsf {A}$ -module $\mathsf {V}$ encodes the relations for tensoring the simple $\mathsf {A}$ -modules with $\mathsf {V}$ . We prove results about the eigenvalues and the right and left (generalized) eigenvectors of $\mathsf {M}_{\mathsf {V}}$ by relating them to characters. We show how the projective McKay matrix $\mathsf {Q}_{\mathsf {V}}$ obtained by tensoring the projective indecomposable modules of $\mathsf {A}$ with $\mathsf {V}$ is related to the McKay matrix of the dual module of $\mathsf {V}$ . We illustrate these results for the Drinfeld double $\mathsf {D}_n$ of the Taft algebra by deriving expressions for the eigenvalues and eigenvectors of $\mathsf {M}_{\mathsf {V}}$ and $\mathsf {Q}_{\mathsf {V}}$ in terms of several kinds of Chebyshev polynomials. For the matrix $\mathsf {N}_{\mathsf {V}}$ that encodes the fusion rules for tensoring $\mathsf {V}$ with a basis of projective indecomposable $\mathsf {D}_n$ -modules for the image of the Cartan map, we show that the eigenvalues and eigenvectors also have such Chebyshev expressions.

CEVERO: A soft-error hardened SoC for aerospace applications

Radiation in the space environment poses a constant threat to circuit devices, and, as a solution, several fault tolerance techniques have been developed. However, some techniques use either proprietary technology or radiation-hardening specialized foundries to manufacture, either of which are not easily accessible to most researchers. There is, yet, another set of rad-hard techniques which provide sufficient fault tolerance to specific aerospace applications. The CEVERO SoC is a custom proofof-concept design that implements techniques as lockstep, dual module redundancy and state recovery in its inner fault tolerance module. It is meant to integrate with the open-source PULP platform and to open a path to a full fault-tolerant SoC.

Visible Colorimetric Dosimetry of UV and Ionizing Radiations by a Dual-Module Photochromic Nanocluster

Radiation dosimeters displaying conspicuous response of irradiance are highly desirable over the recent decade owing to the growing demand of monitoring high-energy radiation and environmental exposure. Herein, we present the first case of dosimetry based on a discrete nanocluster by judicious incorporating heavy Th6 polynuclear centers as radiation attenuator and organic linkers as photo-responsive sensor to enhance chromic response. Rather unusual dual-module photochromic transitions upon multiple external stimuli including UV, β-ray, and γ-ray are integrated into this single material. The striking color change, and more significantly, the visible chromic transition of luminescence in response to accumulating radiation dose allow an on-site quantitative platform for naked-eye detection of ionization radiations over a broad range (1–80 kGy). SC-XRD and DFT calculations revealed that the dual-module photochromism can be attributed to a unique π(TPC)→π*(TPC) intermolecular charge transfer (IeMCT) driven by enhanced π-π stacking interaction between the adjacent TPC moieties upon irradiations.