Architected hydrogels are widely used in biomedicine, soft robots, and flexible electronics while still possess big challenges in strong toughness, and shape modeling. Here, inspired with the universal hydrogen bonding interactions in biological systems, a strain-induced microphase separation path toward achieving the printable, tough supramolecular polymer hydrogels by hydrogen bond engineering is developed. Specifically, it subtly designs and fabricates the poly (N-acryloylsemicarbazide-co-acrylic acid) hydrogels with high hydrogen bond energy by phase conversion induced hydrogen bond reconstruction. The resultant hydrogels exhibited the unique straininduced microphase separation behavior, resulting in the excellent strong toughness with, for example, an ultimate stress of 9.1 ± 0.3 MPa, strain levels of 1020 ± 126%, toughness of 33.7 ± 6.6 MJ m −3 , and fracture energy of 171.1 ± 34.3 kJ m −2 . More importantly, the hydrogen bond engineered supramolecular hydrogels possess dynamic shape memory character, i.e shape fixing at low temperature while recovery after heating. As the proof of concept, the tailored hydrogel stents are readily manufactured by 3D printing, which showed good biocompatibility, load-bearing and drug elution, being beneficial for the biomedical applications. It is believed that the present 3D printing of the architected dynamic hydrogels with ultrahigh toughness can broaden their applications.

Summary Yield in rice is determined mainly by panicle architecture. Using map‐based cloning, we identified an R2R3 MYB transcription factor REGULATOR OF GRAIN NUMBER1 (RGN1) affecting grain number and panicle architecture. Mutation of RGN1 caused an absence of lateral grains on secondary branches. We demonstrated that RGN1 controls lateral grain formation by regulation of LONELY GUY (LOG) expression, thus controlling grain number and shaping panicle architecture. A novel favourable allele, RGN1C, derived from the Or‐I group in wild rice affected panicle architecture by means longer panicles. Identification of RGN1 provides a theoretical basis for understanding the molecular mechanism of lateral grain formation in rice; RGN1 will be an important gene resource for molecular breeding for higher yield.

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The development of cost and environmentally efficient catalysts is essential to transferring phenolic compounds to valuable fuels and chemicals. Various nanocatalysts with different amounts of Ni/Fe have been employed in the steam reforming of phenol, which showed high performance in terms of activity and stability. The conversion and hydrogen yield of phenol reforming over Ni/Fe-catalysts can reach 87% and 81%, respectively. The catalyst can keep its high reactivity for more than 200 h at the steam to carbon ratio (S/C) of 13.3, which is much higher than the previous report of 13 h. Using the newly developed Ni/Fe-catalysts in this research, the hydrogen-rich syngas or carbon nanotube (CNT) could be selectively produced via simply tuning the S/C ratio. The influence of the Ni/Fe ratio and S/C ratio on the steam reforming performance was investigated.

In this paper, we build a model of coupled differential equations concerning pressure, temperature density and velocity in H-T-H-P (High Temperature-High Pressure) gas wells according to the conservation of mass, momentum and energy. We present an algorithm-solving model by the fourth-order Runge-Kutta method. Basic data from the Dayi Well, 7100 m deep in China, are used for case history calculations and a sensitivity analysis is done for the model. Gas pressure, temperature, velocity and density along the depth of the well are plotted with different productions, different geothermal gradients and different thermal conductivities, intuitively reflecting gas flow law and the characteristics of heat transfer in formation. The results can provide a dynamic analysis of production for H-T-H-P gas wells.