Materials with an ultralow density and ultrahigh electromagnetic-interference (EMI)-shielding performance are highly desirable in fields of aerospace, portable electronics, and so on. Theoretical work predicts that 3D carbon nanotube (CNT)/graphene hybrids are one of the most promising lightweight EMI shielding materials, owing to their unique nanostructures and extraordinary electronic properties. Herein, for the first time, a lightweight, flexible, and conductive CNT-multilayered graphene edge plane (MLGEP) core-shell hybrid foam is fabricated using chemical vapor deposition. MLGEPs are seamlessly grown on the CNTs, and the hybrid foam exhibits excellent EMI shielding effectiveness which exceeds 38.4 or 47.5 dB in X-band at 1.6 mm, while the density is merely 0.0058 or 0.0089 g cm , respectively, which far surpasses the best values of reported carbon-based composite materials. The grafted MLGEPs on CNTs can obviously enhance the penetration losses of microwaves in foams, leading to a greatly improved EMI shielding performance. In addition, the CNT-MLGEP hybrids also exhibit a great potential as nano-reinforcements for fabricating high-strength polymer-based composites. The results provide an alternative approach to fully explore the potentials of CNT and graphene, for developing advanced multifunctional materials.

SummaryThe flagellar system of Helicobacter pylori , which comprises more than 40 mostly unclustered genes, is essential for colonization of the human stomach mucosa. In order to elucidate the complex transcriptional circuitry of flagellar biosynthesis in H. pylori and its link to other cell functions, mutants in regulatory genes governing flagellar biosynthesis ( rpoN , flgR , flhA , flhF , HP0244) and whole-genome microarray technology were used in this study. The regulon controlled by RpoN, its activator FlgR (FleR) and the cognate histidine kinase HP0244 (FleS) was characterized on a genome-wide scale for the first time.

Searching for advanced microwave absorption (MA) nanomaterials is one of the most feasible ways to address the increasing electromagnetic pollution in both military and civil fields. To this end, graphene and MXene have won the widespread attention as the main representatives due to their remarkable structures and properties. The common features such as the large aspect ratio, active chemical surface, and varieties of synthesis processes endow graphene and MXene with unique superiorities for developing high‐efficiency MA structures, in particular lightweight assemblies and various hybrids. Meanwhile, the structural and performance differences (such as different conductivities) between them result in distinctive techniques in the design, fabrication, and application of their MA materials. Herein, the research progress in graphene‐ and MXene‐based MA materials is reviewed, with a special focus on advances in general strategies. Moreover, through the comparison between graphene‐ and MXene‐based MA materials, their respective advantages in achieving high‐performance MA are presented. Furthermore, the future challenge, research orientation, and prospect for these MA materials are also highlighted and discussed.

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