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The mini‐outburst of black hole X‐ray binaries (BHXBs) is a re‐bright event of light curve, which is often detected in BHXBs with the low orbital period, such as XTE J1650‐500 (Porb≈7.69±0.02hr$$ {P}_{\mathrm{orb}}\approx 7.69\pm 0.02\kern0.22em \mathrm{hr} $$), GRO J0422+32 (Porb≈5.091850±0.000005hr$$ {P}_{\mathrm{orb}}\approx 5.091850\pm 0.000005\kern0.22em \mathrm{hr} $$) and Swift J1753.5‐0127 (Porb≈3.244±0.001hr$$ {P}_{\mathrm{orb}}\approx 3.244\pm 0.001\kern0.22em \mathrm{hr} $$). Because of its low X‐ray luminosity, the physics properties of mini‐outburst is still unclear. GX 339‐4 is a famous BHXBs with the orbital period Porb=16.9hr$$ {P}_{\mathrm{orb}}=16.9\kern0.22em \mathrm{hr} $$ and present many normal outburst and failed outburst over the past decades. However, the mini‐outburst is not still detected in GX 339‐4. In this work, using the Rossi X‐ray Timing Explorer (RXTE) observations, we investigated the energy spectrum properties of the GX 339‐4 outburst in 2004 and confirmed that the outburst in 2004 is a mini‐outburst. It is very interest that the mini‐outburst has been through a whole state transition from Low/Hard state to High/Soft state. We also give a comparison between the normal outburst in 2002 and the mini‐outburst in 2004. And we find that the two outburst present a similar Hardness‐Intensity diagram and spectral properties, which suggest that the normal outburst and mini‐outburst have a similar physics. We think that the mini‐outburst of GX 339‐4 in 2004 can be well explained by the disk instability model. [ABSTRACT FROM AUTHOR]

One normal outburst and three mini‐outbursts have been detected by Rossi X‐ray Timing Explorer (RXTE) satellite after 2000 in the well‐known black hole X‐ray binary XTE J1550‐564. In our work, we explored the energy spectral properties of the four outbursts and the three mini‐outbursts retained in the Low/Hard state. The results show that the X‐ray spectra of the three mini‐outbursts are harder than that of normal outburst and have no disk component. In the correlation analysis, the Γ−LX/LEdd$$ \Gamma -{L}_{\mathrm{X}}/{L}_{\mathrm{Edd}} $$ anti‐relationship of the three mini‐outbursts suggested that it may be a result of the incomplete evolutionary success of Shakura‐Sunyaev disk. The whole X‐ray spectral correlation evolution shows well the state transition from the Shakura‐Sunyaev disk to the advection‐dominated accretion flow. We think that the three mini‐outbursts may originated from a small discrete accretion event. [ABSTRACT FROM AUTHOR]

Even though numerous bioinspired catalysts have been developed, there remain huge gaps between the artificial and natural catalysts, because it is very difficult to imitate simultaneously the complicated constituents, structures, and synergistic effect of enzymes. We report herein a versatile metalloporphyrinic framework platform, which exhibits high efficiency in bioinspired catalysis, photocatalysis, and asymmetric catalysis. The catalytic properties are highly dependent on the tunable constituents and their cooperation, and are significantly superior to the corresponding molecular catalyst systems which lack the synergistic effects. Since there are numerous functional moieties that can readily be incorporated into the metalloporphyrinic framework platform, a myriad of applications can be simply realized by embedding different functional moieties. [ABSTRACT FROM AUTHOR]

Even though numerous bioinspired catalysts have been developed, there remain huge gaps between the artificial and natural catalysts, because it is very difficult to imitate simultaneously the complicated constituents, structures, and synergistic effect of enzymes. We report herein a versatile metalloporphyrinic framework platform, which exhibits high efficiency in bioinspired catalysis, photocatalysis, and asymmetric catalysis. The catalytic properties are highly dependent on the tunable constituents and their cooperation, and are significantly superior to the corresponding molecular catalyst systems which lack the synergistic effects. Since there are numerous functional moieties that can readily be incorporated into the metalloporphyrinic framework platform, a myriad of applications can be simply realized by embedding different functional moieties. Cats in the cradle: The functionalities of a metalloporphyrinic framework platform are systematically varied for highly efficient bioinspired catalysis, photocatalysis, and asymmetric catalysis. Incorporation of different active species in the pore space/matrices of the platform endows them with cooperative catalytic properties. [ABSTRACT FROM AUTHOR]

Metallophthalocyanines (MPcs) are a class of bioinspired artificial aromatic macrocycles with unique properties of excellent visible light absorption and remarkable photocatalytic activity. However, the catalytic efficiency of MPcs is heavily diminished by strong intermolecular π–π self-aggregation. To solve the self-aggregation problem and realize highly efficient photocatalysis, we develop a strategy to immobilize MPc moieties into porous organic polymers (POPs). The solvothermal reaction between four-branched tetra-amine FePc (TAFP) and three-connected 1,3,5-triformylbenzene (TFB) results in a 3D porous organic material CZJ-30, consisting of highly photoactive FePc moieties. CZJ-30 demonstrates high photoactivity and stability in photoxidation of arylalkanes under visible light irradiation, in which 95% ethylbenzene conversion, >99% acetophenone selectivity and 11,950 turnovers have been realized for photoxidation of ethylbenzene. Compared with its molecular counterpart Fe-Pc, CZJ-30 exhibits superior photocatalytic properties, and offers significant superiority of robustness to self-oxidation and simple recovery for recycling with persisted high photocatalytic efficiency. [ABSTRACT FROM AUTHOR]