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This review covers not only diverse constructions of porphyrin-based MOFs, but also the various therapeutic approaches and multiple biomedical applications. [Display omitted] • A brief introduction of the biomedical advantages of porphyrin-based MOFs is provided in this review. • Porphyrin-based MOFs with diverse synthetic methods are introduced. • Various therapeutic modalities of porphyrin-based MOFs are given and discussed. • Bioimaging applications of porphyrin-based MOFs are described in detail. • The challenges and development prospects of porphyrin-based MOFs are presented. Porphyrins and porphyrin derivatives have attracted significant interest in the fields of catalysis, biosensing, gas storage, solar cells, and biomedical applications owing to their outstanding photophysical and electrochemical properties. Nevertheless, their biological application especially in the therapy and diagnosis of cancer is severely hindered by certain inherent limitations such as self-quenching, weak absorption in the biological spectral window, and poor chemical and optical stability. Porphyrin-based metal organic frameworks (MOFs), a family of novel hybrid porous coordination polymers, have been developed to overcome the limitations of porphyrins and enable their biomedical applications. Porphyrin-based MOFs are constructed using metal ions or clusters and porphyrin ligands through a self-assembly process. Porphyrin-based MOFs maintain the specific properties of porphyrins and can be loaded or modified with functional molecules or drugs to impart therapeutic and imaging abilities. In this review, we discuss the different synthetic approaches of porphyrin-based MOFs and examine the current developments and achievements of porphyrin-based MOFs in the field of biomedical applications, especially cancer therapy and bioimaging in detail. Finally, we discuss the challenges in the biomedical applications of porphyrin-based MOFs and present possible research directions to achieve highly efficient therapeutic effects and high-quality imaging for cancer theranostics. [ABSTRACT FROM AUTHOR]

At present, many mines adopt the filling method. It is particularly important to solve the problem of the long-distance transportation of slurry during the filling process. Based on the high-density filling material of Sanning mine, the experiments were designed to add sodium abietate (SA), triterpene saponin (SJ) and sodium dodecyl sulfonate (K12) with concentrations of 0.0%, 0.2%, 0.4% and 0.6%, respectively, which were used as air entraining agents (AEA). The filling body with the curing age of 7 and 28 days was prepared for various tests, including nuclear magnetic resonance (NMR), and alternating current (AC) impedance tests. The effects of the air entraining agent and curing time on the physical properties, pore structure and AC impedance properties of the filling were obtained. The results show that: (1) within the frequency range of 10−1–105 Hz, the variation trend of AC impedance of the filling body cannot be changed by adding the air entraining agent, and the filling body with the same ratio had a similar topological structure. (2) The filling body with different AEA and curing times can be represented by the same equivalent circuit model, while the maximum chi-square coefficient was 0.46%. (3) Under the condition of a high frequency of 105 Hz, the porosity and uniaxial compressive strength of the filling body with 7 day curing age were linearly correlated with the AC impedance. However, the porosity and uniaxial compressive strengths of the filling body with 28 days curing time were affected by the type of AEA at a high frequency of 105 Hz. [ABSTRACT FROM AUTHOR]

Cloud condensation nuclei (CCN) play an important role in the formation and evolution of cloud droplets. However, the dataset of global CCN number concentration (N CCN) is still scarce due to the lack of direct CCN measurements, hindering an accurate evaluation of its climate effects. Alternative approaches to determine N CCN have thus been proposed to calculate N CCN based on measurements of other aerosol properties, such as particle number size distribution, bulk aerosol chemical composition and aerosol optical properties. To better understand the interaction between haze pollution and climate, we performed direct CCN measurements in the winter of 2018 at the Gucheng site, a typical polluted suburban site in North China Plain (NCP). The results show that the average CCN concentrations were 3.81 × 103 cm−3, 5.35 × 103 cm−3, 9.74 × 103 cm−3, 1.27 × 104 cm−3, 1.44 × 104 cm−3 at measured supersaturation levels of 0.114%, 0.148%, 0.273%, 0.492% and 0.864%, respectively. Based on these observational data, we have further investigated two methods of calculating N CCN from: (1) bulk aerosol chemical composition and particle number size distribution; (2) bulk aerosol chemical composition and aerosol optical properties. Our results showed that both methods could well reproduce the observed concentration (R 2 > 0.88) and variability of N CCN with a 9% to 23% difference in the mean value. Further error analysis shows that the estimated N CCN tends to be underestimated by about 20% during the daytime while overestimated by <10% at night compared with the measured N CCN. These results provide quantitative instructions for the N CCN prediction based on conventional aerosol measurements in the NCP. Unlabelled Image • Conventional measurements of PNSD and bulk aerosol chemical composition perform well in predicting N CCN • The estimation of N CCN based on conventional measurements of AOP can be applicable under SSs lower than 0.114% • Relative deviations between calculated and measured N CCN suggest significant diurnal variations of aerosol hygroscopicity. [ABSTRACT FROM AUTHOR]

The current conventional photo-therapeutic agents often show low therapy efficacy because of their single treatment model, the limited penetration depth of excitation light and hypoxia in the tumor microenvironment (TME). Herein, a new type of phthalocyanine manganese (MnPcE 4) photosensitizer with strong NIR absorption was designed and fabricated for the first time, and was used to modify pure Bi nanomaterials to obtain an intelligent multifunctional Bi/MnPcE 4 nanocomposites. The Mn2+ in the Bi/MnPcE 4 nanocomposite could catalyze H 2 O 2 to generate O 2 , thus helping to overcome TME hypoxia and enhancing the photodynamic therapy (PDT) efficacy. Further, the nanocomposites showed excellent T 1 -weighted MRI performance. Our novel use of a pure metal Bi core, offers lower toxicity, higher CT imaging performance, and a photothermal therapy (PTT) effect triggered by 808 nm near infrared (NIR) laser. Moreover, in vivo fluorescence imaging (in vivo FL) vividly showed that the nanocomposite rapidly accumulates in tumor sites due to the enhanced permeability and retention (EPR) effect and metabolized in the organs. The presence of Bi enables the use of these nanocomposites as a CT contrast agent, and the Mn content enables them to be used in MRI. This triple imaging ability implies that our nanocomposites have a high potential for use in imaging directed tumor therapy. Image 1 [ABSTRACT FROM AUTHOR]

Black carbon (BC) aerosols play an important role in modifying the PBL meteorology and severity of haze pollution through its radiative effect (Ding et al. 2016). The radiative effect of BC strongly depends on its mixing state or coating thickness, which is subject to the aging process in the atmosphere (Cheng et al. 2006, 2008). North China Plain (NCP) is one of the areas where both severe haze and high abundance of BC have been reported. By using a single particle soot photometer (SP2) and complimentary measurements, we investigated the aging of BC during several severe haze events in the North China Plain during our winter campaign in 2018. We calculated the size-resolved mixing state and aging rate of BC in the ambient air under different pollution levels. Our results show a fast aging of BC especially during the haze events with high concentrations of air pollutants and condensable vapors. The occurrence of fog episodes in the campaign enables us to analyze the BC-droplet interactions, especially the effect of aerosol size and coating thickness on its activation and removal, which is key for understanding the aerosol-cloud and aerosol fog interactions. Moreover, we find that most coated BC particles can be classified to a "core-shell" type while only a small fraction of BC-containing particles is in an "attached" type. It suggests that the traditional Core-Shell model should still be applicable for modeling the radiative properties of BC in the North China Plain. Based on the Mie model calculation, we determined their absorption enhancement factor of BC due to the aging process and discussed its implication to the formation of severe haze.References:Ding, A. J., Huang, X., Nie, W., Sun, J. N., Kerminen, V. M., Petaja, T., Su, H., Cheng, Y. F., Yang, X. Q., Wang, M. H., Chi, X. G., Wang, J. P., Virkkula, A., Guo, W. D., Yuan, J., Wang, S. Y., Zhang, R. J., Wu, Y. F., Song, Y., Zhu, T., Zilitinkevich, S., Kulmala, M., and Fu, C. B.: Enhanced haze pollution by black carbon in megacities in China, Geophys. Res. Lett., 43, 2873-2879, 10.1002/2016gl067745, 2016.Cheng, Y. F., Eichler, H., Wiedensohler, A., Heintzenberg, J., Zhang, Y. H., Hu, M., Herrmann, H., Zeng, L. M., Liu, S., Gnauk, T., Bruggemann, E., and He, L. Y.: Mixing state of elemental carbon and non-light-absorbing aerosol components derived from in situ particle optical properties at Xinken in Pearl River Delta of China, J. Geophys. Res.-Atmos., 111, 18, 10.1029/2005jd006929, 2006.Cheng, Y. F., Wiedensohler, A., Eichler, H., Su, H., Gnauk, T., Brueggemann, E., Herrmann, H., Heintzenberg, J., Slanina, J., Tuch, T., Hu, M., and Zhang, Y. H.: Aerosol optical properties and related chemical apportionment at Xinken in Pearl River Delta of China, Atmos. Environ., 42, 6351-6372, 10.1016/j.atmosenv.2008.02.034, 2008. [ABSTRACT FROM AUTHOR]

Black carbon (BC) is the most important light-absorbing species in the atmosphere and has a strong positive direct radiative forcing. Recent studies found that BC-containing particles may also modify the structure of planetary boundary layer and thus enhance haze pollution, especially in densely populated areas, for instance, in China. It is however difficult to quantify these effects due to their complex mixing state, hygroscopicity and the high spatial variability of concentration. During an intensive field campaign conducted in the North China Plain in a cold season, the mass size distribution and mixing state of BC was measured with a single particle soot photometer (SP2). During a severe haze event, the BC mass concentration exceeded 15 ug m-3. Stemming from the strong aging process under high relative humidity condition, freshly emitted BC particle was observed to turn into internally mixing within a short time scale. To understand the variation of the hygroscopicity of BC during its aging process, the hygroscopic growth factor of BC-containing particles was measured with a combination of a hygroscopic tandem differential mobility analyzer and a SP2. The particle hygroscopic growth factor was found to be correlated with the volume fraction of BC. During haze events, a fraction of the more-hygroscopic mode particles was observed to contain BC cores; while a minor fraction of the hydrophobic mode particles contained no BC. [ABSTRACT FROM AUTHOR]