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This article presents an experiment of rocket-triggered lightning to 10 kV power distribution lines and the characteristics of lightning current at Guangzhou Field Experiment Site for Lightning Research and Testing during 2018–2019. The return strokes (RSs) current of the triggered-lightning flashes in this study exhibits a shorter half-peak width and similar risetime and peak current compared with those of subsequent strokes current from natural lightning. The peak current of RSs shows strong power function correlations with charge transfer within 1 ms and action integral within 1 ms of RSs, with R2 of 0.80 and 0.92, respectively. Besides, the peak current of RSs is proportional to the average rate rise of RSs (dI/dt). We recommend the double HEIDLER function to simulate the RS current and provide accurate raw data for the study of lightning protection.

The impulse grounding performance of distribution lines tower is the key factor to lightning protection. Few field high-current impulse test researches are conducted on distribution line tower. In this paper, we used a mobile high-current impulse generator to conduct test on a 10 kV distribution line tower. The peak value of the current injection is 6 kA to 16 kA. The impulse impedance and the surface potential distribution are measured and analyzed. Based on the CDEGS software, an equivalent modeling of the experiment was carried out. The influence of soil ionization was taken into account by the method of changing the conductor radius through two rounds of calculation. The simulation and measured results were basically consistent. Experiments have shown that the soil ionization effect has an important impact on lightning performance of distribution line tower. The graphite earthing modules (GEMs) and pulling wires can significantly reduce the impulse impedance of the tower. The potential rise of the earth surface at a distance of 30 m from the tower can reach 1 kV at peak, under an injection of 7.15 kA.

Fabrication of multifunctional catalysts has always been the pursuit of synthetic chemists due to their efficiency, cost-effectiveness, and environmental friendliness. However, it is difficult to control multi-step reactions in one-pot, especially the spatial compartmentalization of incompatible active sites. Herein, we constructed metal-organic framework (MOF) composites which regulate the location distribution of metal nanoparticles according to the reaction path and coupled with the diffusion of substrates to achieve tandem reaction. The designed UiO-66-Pt-Au catalyst showed good activity and selectivity in hydrosilylation-hydrogenation tandem reaction, because the uniform microporous structures can control the diffusion path of reactants and intermediates, and Pt and Au nanoparticles were arranged in core-shell spatial distribution in UiO-66. By contrast, the low selectivity of catalysts with random deposition and physical mixture demonstrated the significance of artificial control to the spatial compartmentalization of active sites in tandem catalytic reactions, which provides a powerful approach for designing high-performance and multifunctional heterogeneous catalysts.

Soybean is an important crop, so it is very important to forecast soybean price trend, which can stabilize the market. This paper presents a Synthesis Method with Multistage Model (SMwMM) in order to identify and forecast soybean price trend in China. In the previous work,Toeplitz Inverse Covariance-based Clustering(TICC) has been applied to cluster the prices of four variables. The research have found that there are four patterns in soybean market price, which could be explained by economic theory. This paper consider four patterns as market risk levels. Based on the clustering results, we used Long short-term memory(LSTM) to forecast the prices of these four variables. Multivariate long short-term memory(MLSTM) is then used to classify soybean price to determine level of risk . Experimental results show that :(1)The LSTM model has achieved great fitting effect and high prediction accuracy;(2) The performance of MLSTM-FCN and MALSTM-FCN is better than that of LSTM-FCN and ALSTM-FCN. Furthermore,MALSTM-FCN had the higher accuracy than MLSTM-FCN, which reached 76.39%.

Majority of cancer patients die from cancer metastases. The physical stimulation produced by microenvironment regulates invasive behavior of cancer cells. Blood vessel is one of the “pathways” for cancer to metastasize, in which tumor cells need to cross the endothelial barrier for intravasation and extravasation. Tumor vessels are arranged in untraditional hierarchies and characterized with rupture, bend, swell and high permeability that are beneficial to intravasation of cancer cell. Abnormal vessels are accompanied with uneven blood flow, increased compression and interstitial fluid pressure. Meanwhile, excessive proliferation of tumor leads to low oxygen pressure in solid tumor. The aberrant tumor mechanical microenvironment changes the biochemical and mechanical signal transduction of endothelial cells and participates in tumor progression. Many current researches focus on how chemical signals regulate endothelial cell function while the role of physical cues is unclear. In this review, the role of endothelial cells in the regulation of shear stress, intercellular force, extracellular matrix and pressure on tumor progression is summarized.

The thermal behaviour of the surge arrester is vital to assess its operational condition. The surge arrester usually shows a process of temperature rising during a long-term operation, particularly after subjecting to a surge. Therefore, the research on the temperature characteristics of ZnO arresters contributes to achieve the goal of the performance changes of the ZnO arresters over different temperatures. In this study, based on four types of ZnO arresters from different factories, the variation of the volt–ampere curve, DC characteristic parameters and non-linear coefficient of the whole ZnO arrester at different temperatures were analysed. The relationship between the temperature and non-linear coefficients was obtained through the method of the extraction of the non-linear coefficients. Through the multiple impulse current tests, the temperature of the arrester was well calculated by measuring the corresponding volt–ampere curve, and the relationship between the surface temperature and V–I characteristics of the arrester is verified by the impulse test results. The obtained results provide a new idea for the application of the surface temperature of the arrester in the performance monitoring of the arrester.

Metal–organic frameworks (MOFs) are suitable for studying host–guest chemistry by virtue of their component diversities, porous structures, and facile production. As the host materials, MOFs have b...

The host–guest interactions between baicalein (BALE) and cucurbit[8]uril (Q[8]) and the corresponding properties of the inclusion complex were studied using 1H NMR, IR and UV–vis spectroscopy and DTA. The results showed that BALE forms an inclusion compound (1:1) with Q[8], and the properties of baicalein are changed by cucurbit[8]uril.

Two special cases of dart leader propagation were observed by the high-speed camera in the leader/return stroke sequences of a classical triggered lightning flash and an altitude-triggered lightning flash, respectively. Different from most of the subsequent return strokes preceded by only one leader, the return stroke in each case was preceded by two leaders occurring successively and competing in the same channel, which herein is named leader-chasing behavior. In one case, the polarity of the latter leader was opposite to that of the former leader and these two combined together to form a new leader, which shared the same polarity with the former leader. In the other case, the latter leader shared the same polarity with the former leader and disappeared after catching up with the former leader. The propagation of the former leader in this case seems not to be significantly influenced by the existence of the latter leader.

Mechanical microenvironment plays a critical role in cancer drug resistance and this study supposed that suspension state might be involved in drug resistance of breast tumor cells. The viability of cell was detected by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. Cell cycle and apoptosis were detected by flow cytometry. Gene and protein were tested by RT-qPCR and Western blot, respectively. Drug resistance of MDA-MB-231 cells cultured for 72 h under suspension state was significantly increased. Suspension state was found to induce the overexpression of adenosine triphosphate-binding cassette subfamily C member 3 (ABCC3) in MDA-MB-231 cells. Silencing of ABCC3 significantly decreased drug resistance of suspension MDA-MB-231 cells. Moreover, suspension state was able to increase lamin A/C accumulation in MDA-MB-231 cells and lamin A/C regulated the expression of ABCC3. Moreover, lamin A/C knockdown also decreased drug resistance of suspension MDA-MB-231 cells, but the effect on drug resistance was less than that of ABCC3 knockdown. Suspension state plays a vital role in promoting drug resistance of MDA-MB-231 cells by inducing ABCC3 overexpression, and lamin A/C accumulation is associated with this process.

The characterization and comparison of sludge ashes at various ashing temperatures were carried out to study the relationship between the ashing fusibility, physicochemical properties, and thermogr...

Heterogeneous catalysts have made outstanding advancements in pollutants elimination as well as energy and materials production over the past decades. Single-atom alloys (SAAs) are novel environmental catalysts prepared by dispersing single metal atoms on other metals. Integrating the advantages of single atom and alloys, SAAs can maximize atom utilization, reduce the use of noble metals and enhance catalytic performances. The synergistic, electronic and geometric effects of SAAs are effective to modulate the activation energy and adsorption strength, consequently breaking linear scaling relationship as well as offering an excellent catalytic activity and selectivity. Moreover, SAAs possess clear atomic structure, active sites and reaction mechanisms, providing an opportunity to tailor catalytic properties and develop effective environmental catalysts. In this review, we provide the recent progress on synthetic strategies, catalytic properties and catalyst design of SAAs. Furthermore, the applications of SAAs in environmental catalysis are introduced towards catalytic conversion and elimination of different air pollutants in many important reactions including (electrochemical) oxidation of volatile organic compounds (VOCs), dehydrogenation of VOCs, CO2 conversion, NOx reduction, CO oxidation, SO3 decomposition, etc. Finally, challenges and opportunities of SAAs in a broad environmental field are proposed.

Macrophages are involved in the early inflammation during tissue repair and play a distinctive role in maintaining the stability of the tissue microenvironment. However, it is still very difficult to accurately regulate the phenotypic transformation of macrophages during bone repair. The current study innovatively used 4-octyl itaconate (OI), a cell-permeable derivative of an endogenous anti-inflammatory metabolite itaconate (IA), to regulate the polarization of macrophages and enhance the quality of bone repair. Chitosan (CS) was selected as a bridge in coating OI on demineralized bone matrix (DBM) scaffold to generate three-dimensional (3D) bone integration scaffold (OI/CS/DBM scaffold). Whether this metabolite derivative can exert the same anti-inflammatory effect as the metabolite itself was validated both in vitro and in vivo. In vitro cellular results showed that both OI and OI/CS/DBM scaffold could promote the formation of anti-inflammatory phenotype of macrophages, and the osteogenic differentiation of mesenchymal stem cells (MSCs) was indirectly enhanced by macrophage supernatant medium. In vivo studies of a rat skull defect model further proved that the OI/CS/DBM scaffold could improve the bone integration. In this study, the OI/CS/DBM scaffold was successfully fabricated as a vehicle for delivering OI, which was proved to have the ability to promote bone integration by regulating early inflammation. The present results may provide a novel method to improve bone repair with metabolites derivative to regulate the inflammation.

Low-intensity pulsed ultrasound (LIPUS) is a noninvasive technique that has been shown to affect cell proliferation, migration, and differentiation and promote the regeneration of damaged peripheral nerve. Our previous studies had proved that LIPUS can significantly promote the neural differentiation of induced pluripotent stem cell-derived neural crest stem cells (iPSCs-NCSCs) and enhance the repair of rat-transected sciatic nerve. To further explore the underlying mechanisms of LIPUS treatment of iPSCs-NCSCs, this study reported the gene expression profiling analysis of iPSCs-NCSCs before and after LIPUS treatment using the RNA-sequencing (RNA-Seq) method. It was found that expression of 76 genes of iPSCs-NCSCs cultured in a serum-free neural induction medium and expression of 21 genes of iPSCs-NCSCs cultured in a neuronal differentiation medium were significantly changed by LIPUS treatment. The differentially expressed genes are related to angiogenesis, nervous system activity and functions, cell activities, and so on. The RNA-seq results were further verified by a quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR). High correlation was observed between the results obtained from qRT-PCR and RNA-Seq. This study presented new information on the global gene expression patterns of iPSCs-NCSCs after LIPUS treatment and may expand the understanding of the complex molecular mechanism of LIPUS treatment of iPSCs-NCSCs.

To build a three-dimensional co-culture model in a microfluidic device for cancer research and evaluate its feasibility by investigating cancer stem-like cells (SCs) induced migration of human umbilical vein endothelial cells (ECs).The microfluidic device provided two-dimensional and three-dimensional (2D/3D) culture and co-culture environments without affecting cell viability. The device also provided an effective concentration for the chemiotaxis of cells, and to support real-time monitoring of cell behavior. In this model, SCs significantly increased the migration area of ECs with a hepatocarcinoma cell line (MHCC97H; MCs). The presence of ECs also induced both MCs and SCs invasion into Matrigel. The migration area of MCs and SCs significantly increased when co-cultured with ECs.This 3D co-culture microfluidic model is a suitable model in cancer research. Compared with MCs, SCs had greater potential in inducing EC migration and interacting with ECs.

Metal-organic framework (MOF)-based derivatives have attracted an increasing interest in various research fields. However, most of the reported papers mainly focus on pristine MOF-based derivatives, and research studies on functional MOF-based derivative composites are rare. Here, a simple strategy has been reported to design functional MOF-based derivative composites by the encapsulation of metal nanoparticle (MNP) in MOF matrixes (MNP@MOF) and the high-temperature calcination of MNP@MOF composites. The as-prepared MNP@metal oxide composites with a hierarchical pore structure exhibited excellent catalytic activity and high stability for the CO oxidation reaction.

Metal-organic frameworks (MOFs) have drawn increasing attentions as promising candidates for functional devices. Herein, we present MOF films in constructing memory devices with alcohol mediated resistance switching property, where the resistance state is controlled by applying alcohol vapors to achieve multilevel information storage. The ordered packing mode and the hydrogen bonding system of the guest molecules adsorbed in MOF crystals are shown to be the reason for the alcohol mediated electrical switching. This chemically mediated memory device can be a candidate in achieving environment-responsive devices and exhibits potential applications in wearable information storage systems. ASTAR (Agency for Sci., Tech. and Research, S’pore) MOE (Min. of Education, S’pore) Accepted version

Conventional diffraction gratings are designed so that most of the light striking the grating is diffracted toward the “first-order beam” direction, but in practice, some of the light may be diffracted towards the “second-order beam” direction, so that the light striking a particular sensor pixel may be a combination of both first- and second-order components. This causes errors in the output of diffraction-grating based UV–visible spectrometers. A new method has been developed to correct such errors by calibrating the optical system with a UV-excluded standard (such as an orange tile) and a UV-included standard (such as a white tile). These two calibrations can predict the relationship between first-order-only signals and first-and-second-order combined signals at sensor pixels (nominal wavelengths) where there is second-order light, and thus help correct the second-order diffraction error. This compensation method applied on the reflectance measurement of a set of color ceramic tiles showed significant improvement on the accuracy of the result. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 189–192, 2017

A facile encapsulation strategy for the preparation of metal layer/metal–organic framework (metal/MOF) hybrid thin films, by alternately growing MOF thin films and sputter-coating metal layers, is reported. The controlled species of the MOF thin films and metal layers, as well as the designed thickness of MOF thin films, endow the resulting hybrid thin films with improved functional and design flexibility. Importantly, the metal/MOF hybrid thin films, with well-defined sandwich structures, exhibit excellent selective catalytic activity, derived from MOFs acting as molecular sieves and the metal layers providing active sites.

As a biophysical cue, matrix stiffness can decide the stem cell fate. However, most methods to construct three-dimensional (3D) scaffolds may change the 3D microstructure while altering their mechanical properties. In this study, demineralized bone matrix scaffolds with different compressive modulus (66.06 ± 27.83 MPa (high), 26.90 ± 13.16 MPa (medium), and 0.67 ± 0.14 MPa (low)) were constructed by controlling the decalcification duration (1 h, 12 h, and 5 days), respectively. The pore size and porosity have no significant difference between the scaffolds before and after decalcification. Cell experiments indicated that the low scaffolds could promote the osteogenic differentiation of bone marrow mesenchymal stem cells (MSCs) in vitro. Rat subcutaneous implantation experiments further demonstrated that the low scaffolds could efficiently improve the cell infiltration, deposition of collagen fibers, and positive osteocalcin and osteopontin expression of endogenous cells as well as angiogenesis. Finally, rabbit femoral condylar defect experiments proved that the low scaffolds could significantly promote the bone repair and integration and stromal cell derived factor-1α/CXC chemokine receptor signal pathway was essential for the stiffness-mediated bone repair. These investigations provided a novel method for fabricating 3D bone grafts with different stiffness, which is also of great significance for studying the effect of stiffness on the biological behavior of MSCs in three dimensions.

This report describes a facile strategy that has the capability of adjusting different surface hydrophilicities/hydrophobicities of catalysts by covering metal–organic frameworks with graphene oxide and reduced graphene oxide. The catalysts exhibit remarkable catalytic selective performance for the hydrogenation of different hydrophobic and hydrophilic reactants.

Implanted bone scaffolds often fail to successfully integrate with the host tissue because they do not elicit a favorable immune reaction. Properties of bone scaffold not only provide mechanical and chemical signals to support cell adhesion, migration, proliferation and differentiation, but also play a pivotal role in determining the extent of immune response during bone regeneration. Appropriate design parameters of bone scaffold are of great significance in the process of developing a new generation of bone implants. Herein, this article addresses the recent advances in the field of bone scaffolds for immune response, particularly focusing on the physical and chemical properties of bone scaffold in manipulating the host response. Furthermore, incorporation of bioactive molecules and cells with immunoregulatory function in bone scaffolds are also presented. Finally, continuing challenges and future directions of scaffold-based strategies for modulating immune microenvironment are discussed.

This study investigates whether platelet-rich plasma (PRP) is an activator of tendon-derived stem cells (TDSCs) to promote regeneration of Achilles tendon post-rupture in rats. In the in vitro study, PRGF (activated PRP) significantly enhanced cell DNA synthesis, improved viability and promoted proliferation, while facilitating cell migration and the recruitment of TDSCs. In addition, TDSCs were mixed with collagen and PRP to form collagen-TDSC constructs (CTC) and PRP-collagen-TDSC constructs (PCTCs). After 3 weeks of culture in vitro, we found that most of the encapsulated TDSCs in the CTCs and PCTCs were still alive, while cells in the PCTCs showed a more aligned arrangement compared to the CTCs. In addition, the micro-structure of PCTC showed more obvious fibre-like tissues and formed a cyclic microvascular structure. The tenocyte-related genes types I and III collagen, Tenascin-C and Scleraxis of TDSCs in the PCTCs and CTCs were upregulated with time, and PCTCs showed more significance than CTCs (p < 0.05). After in vivo transplantation, the CTCs and PCTCs showed stimulatory effects on Achilles tendon healing. Moreover, the PCTCs improved the macroscopic appearance, histological morphology and biomechanical strength of ruptured Achilles tendon better than CTC. These results indicate that PRP can activate TDSCs to improve the quality of Achilles tendon rupture healing in the early stages. Copyright © 2015 John Wiley & Sons, Ltd.

Aims Severe hypoxia always inhibits the cell proliferation, osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs), and hinders bone defect repair. Herein we explored the effects of mechano-growth factor (MGF) E peptide on the proliferation and osteogenic differentiation of BMSCs under severe hypoxia. Materials and methods CoCl2 was utilized to simulate severe hypoxia. MTS was used to detect cell viability. Cell proliferation was verified through flow cytometry and EdU assay. Osteogenic differentiation of BMSCs and osteoblast-specific genes were detected through alkaline phosphatase (ALP) and Alizarin Red S staining, and quantitative real-time PCR, respectively. Hypoxia-inducible factor 1α (HIF-1α), p-ERK1/2 and p-Akt expression levels were detected through western blotting and immunofluorescence. Key findings Severe hypoxia induced HIF-1α accumulation and transferring into the nucleus, and reduced cell proliferation and osteogenic differentiation of BMSCs. The expression levels of osteoblast-specific genes were markedly decreased after differentiation culture for 0, 7 or 14 days. Fortunately, MGF E peptide inhibited HIF-1α expression and transferring into the nucleus. Cell proliferation and osteogenic differentiation of BMSCs could be recovered by MGF E peptide pretreatment. MEK-ERK1/2 and PI3K-Akt signaling pathway were confirmed to be involved in MGF E peptide regulating the abovementioned indexes of BMSCs. What's more, short-time treatment with MGF E peptide alone promoted the osteogenic differentiation of BMSCs as well. Significance Our study provides new evidence for the role of MGF E peptide in regulating proliferation and osteogenic differentiation of BMSCs under severe hypoxia, which may potentially have therapeutic implication for bone defect repair.

Functional organic molecules/metal-organic frameworks composites can be obtained by in situ crystalline structure transformation from ZIF-L to ZIF-8-L under double solvent conditions. Interestingly, the as-prepared molecules/ZIF-8-L composites with the leaf-like morphology exhibit good fluorescence properties and size selectivity in fluorescent quenchers due to the molecular sieving effect of the well-defined microporous ZIF-8-L.

The molecular geometries and electronic structures of 14 fluorides are optimized using density functional theory (DFT) B3LYP/6-31G*, B3P86/6-31G* and Moller–Plesset perturbation theory MP2/6-31G* methods. EHOMO, ELUMO, ΔE, μ, QF, QM and V are chosen as the structural descriptors. The acute toxicity (−lg LC50) of fluorides to rats along with the above structural parameters are used to establish the quantitative structure–activity relationships (QSARs). The results show that the models based on the DFT-B3LYP/6-31G* is better than that based on B3P86/6-31G* and MP2/6-31G* methods. The toxic mechanism is controlled mainly by electronic factor QF (the maximum net atomic charge on fluorides). The QSAR relationship between the electronic parameters QF and the toxicity −lg LC50 is: −lg LC50 = 0.032 + 7.037QF ( R adj 2 = 0.869 , SE = 0.37097, F = 27.578, P = 0.013). An overall cross-validation correlation coefficient is then obtained using leave-one-out method and the calculated cross-validation coefficient (q2) value is 0.660. The predicted toxic values using the above equation are in good agreement with the experimental values, and the QSAR model has good stability and strong prediction ability.

Stem cells have the ability to self-renew and to differentiate into multiple mature cell types during early life and growth. Stem cells adhesion, proliferation, migration and differentiation are affected by biochemical, mechanical and physical surface properties of the surrounding matrix in which stem cells reside and stem cells can sensitively feel and respond to the microenvironment of this matrix. More and more researches have proven that three dimensional (3D) culture can reduce the gap between cell culture and physiological environment where cells always live in vivo. This review summarized recent findings on the studies of matrix mechanics that control stem cells (primarily mesenchymal stem cells (MSCs)) fate in 3D environment, including matrix stiffness and extracellular matrix (ECM) stiffness. Considering the exchange of oxygen and nutrients in 3D culture, the effect of fluid shear stress (FSS) on fate decision of stem cells was also discussed in detail. Further, the difference of MSCs response to matrix stiffness between two dimensional (2D) and 3D conditions was compared. Finally, the mechanism of mechanotransduction of stem cells activated by matrix mechanics and FSS in 3D culture was briefly pointed out.

Low-intensity pulsed ultrasound (LIPUS) is a noninvasive technique that has been shown to affect cell proliferation, migration, and differentiation and promote the regeneration of damaged peripheral nerve. Our previous studies had proved that LIPUS can significantly promote the neural differentiation of induced pluripotent stem cell-derived neural crest stem cells (iPSCs-NCSCs) and enhance the repair of rat-transected sciatic nerve. To further explore the underlying mechanisms of LIPUS treatment of iPSCs-NCSCs, this study reported the gene expression profiling analysis of iPSCs-NCSCs before and after LIPUS treatment using the RNA-sequencing (RNA-Seq) method. It was found that expression of 76 genes of iPSCs-NCSCs cultured in a serum-free neural induction medium and expression of 21 genes of iPSCs-NCSCs cultured in a neuronal differentiation medium were significantly changed by LIPUS treatment. The differentially expressed genes are related to angiogenesis, nervous system activity and functions, cell activities, and so on. The RNA-seq results were further verified by a quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR). High correlation was observed between the results obtained from qRT-PCR and RNA-Seq. This study presented new information on the global gene expression patterns of iPSCs-NCSCs after LIPUS treatment and may expand the understanding of the complex molecular mechanism of LIPUS treatment of iPSCs-NCSCs.

Chain-like MoS2 assemblies consisting of hexagonal MoS2 nanoparticles (20–60 nm) have been successfully synthesized in a Triton X-100/cyclohexane/hexanol/water W/O reverse microemulsion in the presence of (NH4)2MoS4 as the molybdenum source and NH2OH·HCl as the reducing agent. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and UV-vis diffuse reflectance absorption spectra. The influence of synthetic parameters such as acidity, water/oil ratio (ω0), aging time and annealing temperature on the formation of MoS2 assemblies was investigated. TEM analysis showed that these synthetic factors played important roles in controlling the size of MoS2 nanoparticles and the length of the chain-like MoS2 assemblies. XRD analysis indicated that the well-crystallized MoS2 nanoparticles could be obtained by annealing the precursors at 700°C for 2 h under a flow of N2 atmosphere. In addition, the as-prepared chain-like MoS2 nanoparticles exhibited excellent photocatalytic H2 activity in Ru(bpy)32+-MoS2-H2A three-component molecular systems under visible light irradiation.