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The porous organic polymers have been considered as effective materials for gas storage and adsorption. Herein, we synthesized highly crystalline nitrogen-rich covalent triazine frameworks (CTFs) by polycondensation for preparing the novel hyper-cross-linked conjugated polymers (HCCPs) with tunable specific surface area and pore volume through coupling Friedel-Crafts reaction, in which 1,4-Bis(chloromethyl)benzene and 4,4-Bis(chloromethyl)biphenyl as the expansion molecules were pillared between the layers of CTF-HUST. This technology not only increased the specific surface area and total pore volume of CTF-HUST by 2.56 and 4.68 times, but also greatly enhanced the utilization of adsorption sites of CTF-HUST. The HCCP2-1.25 exhibited the highest surface area (1349.29 m2g-1) among these HCCPs and demonstrated excellent adsorption performance for ethyl acetate (1605.14 mg/g), ethanol (1371.49 mg/g), 1,2-Dichloroethane (1971.68 mg/g), benzene (1151.77 mg/g) and toluene (1024.28 mg/g) due to the multiple C-H…O, C-H…Cl, O-H…N and C-H…π interactions between volatile organic compounds (VOCs) and HCCPs framework. Moreover, CO2 and H2 storage capacities of the HCCP2-1.25 were 8.02 wt % and 1.54 wt %, 1.66 and 1.67 times higher than CTF-HUST, respectively. This study developed a simple and effective molecular expansion strategy to synthesize a series of novel high-surface-area porous polymers for potential applications in the environmental field.

This paper presents the experimental and simulation study of circular steel arches attached on the steel columns through the rigid connection, which are loaded to failure under static load. Local buckling of the top flange at the mid-span arch or the bottom flange at end of the arch occurs under the ultimate load. The deformation shape is approximately antisymmetrical with a 0.2 rise-to-span ratio and is symmetrical with a 0.1 rise-to-span ratio. A simplified model is proposed as an arch with elastic horizontal and rotational end restraints. The corresponding stiffness is determined as equivalent horizontal and rotational stiffness at each arch end under the ultimate load. Then a large amount of parameter analysis is conducted to investigate the influence of the elastic supported stiffness, load type, rise-to-span ratio, and slenderness on the ultimate resistance. The finding is that the reduction of the ultimate resistance for the arch with the horizontal and rotational elastic end restraints is maximal under the uniform full-span vertical load, minimal under the concentrated load. Finally, a design method of the steel arch with elastic horizontal and rotational end restraints is proposed taking both ultimate resistance and maximum horizontal displacement of the supports into account for engineering reference.

The low oxygen concentration limits the therapeutic efficacy of photodynamic therapy in treating cancer cells in hypoxia, since the cytotoxic 1O2 can't be effectively generated in this condition. To overcome this, we load photosensitizer into perfluorocarbon nanodroplet, which has a high oxygen capacity to enrich O2 for photodynamic consumption. Under the well-controlled hypoxic condition, we test its efficacy both in vitro and in vivo. This method can be successfully used for destroying cancer cells in hypoxic condition.

The stiffness of the supports has an influence on the buckling modes and buckling loads of the arch. This paper investigates the in-plane nonlinear behavior and stability of shallow circular arches with elastic horizontal supports that are uniformly subjected to a radial load by the principle of virtual work. The three limiting shallowness values and the critical flexibility of the elastic horizontal supports are derived to differentiate the buckling mode. As the flexibilities of the elastic horizontal supports of an arch increase, the buckling load of the arch decreases, and the central radial displacement increases. And the buckling mode of the arch would then be changed from asymmetric bifurcation buckling to asymmetric bifurcation buckling after the occurrence of snap-through buckling. Then, snap-through buckling occurs, and finally, there is no buckling. Then the parameters including rise-to-span ratio( f / L ) and load type are further investigated. An experimental model is designed to verify the analytical results. Finally, a design method for a shallow circular arch with elastic horizontal supports is proposed with the requirement of the elastic-plastic buckling load carrying capacity and the maximum horizontal displacement of the supports for engineering reference.

The authors propose a new tuned viscous mass damper (TVMD) coupled wall system for use in high-rise buildings. In this novel structural system, the TVMDs are arranged in a zig-zag configuration to couple wall piers in order to control both lateral inter-story drifts and floor accelerations. This novel structural system is used in this study to investigate the seismic performance of a 15-story prototype building. A nonlinear finite element model of the TVMD coupled wall (TCW system) is developed via the opensource finite element analysis software OpenSees. The TVMD is modeled by means of a newly compiled element named InertiaTruss, and the behavior of the coupled wall is simulated using a well-established multi-layer shell element approach. The seismic behavior of this novel TCW system is compared with walls coupled with conventional reinforced concrete beams (RCW system) and with viscous dampers (VCW system). The results indicate that, with a proper tuning design, seismic response parameters such as inter-story drift and floor acceleration are reduced by up to 16% and 28%, respectively, in the TCW system compared to the RCW system. The TCW system also shows better control of floor acceleration than the VCW system, though drifts are comparable. The force demands in the TVMD-to-wall joints are small due to the benefit of the TVMD zig-zag configuration. The analysis results also indicate that the effect of detuning in this new system is insignificant even when subjected to severe motions.

Research of superconducting nanowire single-photon detectors (SNSPDs) has been progressing rapidly in recent years. The combined properties of high efficiency, low noise, and fast speed of SNSPDs permit its applications ranging from long-distance quantum teleportation to moon-to-earth optical communications. Here we briefly discussed recent progress of SNSPDs, in particular (1) tungsten-silicide SNSPDs, (2) waveguide-integrated SNSPDs, and (3) a few applied demonstrations.

A hybrid coupled wall system, where steel coupling beams couple steel reinforced concrete (SRC) walls in series, has been recognized as an alternative to reinforced concrete (RC) coupled wall systems for enhanced seismic performance of high-rise buildings. A key issue of this system is seismic design of steel coupling beam-to-SRC wall joints. This paper presents a series of full-scale tests to investigate the cyclic behavior and strength capacity of the steel coupling beam-to-SRC wall joints, where a steel beam was rigidly connected to an encased steel column in wall boundary using a fully welded connection detail. The steel beam-to-SRC wall joints failed in panel shear mode, characterized by yielding of the steel web panel and joint transverse reinforcement, and crisscrossed-diagonal cracking and crushing of joint panel concrete. A design model for calculating the nominal strength of the steel beam-to-SRC wall joint is presented. The accuracy of the design model was verified against the collected test data and additional finite element (FE) analysis. The experimental tests and FE analysis also identified that severe vertical cracks might develop along the inner side of wall boundary element, due to horizontally tensile forces induced by the steel beam flange. Increased amount of horizontally distributed rebar is recommended to be assigned in around the join region, in order to control such unwanted damage. In addition, the test results of one specimen demonstrated that properly designed beam-to-wall joint remained slightly damaged when the steel coupling beam fully developed its plastic rotation.