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The dye molecules behaving as photosensitizers in dye-sensitized solar cells are the most critical factors to determine the power conversion efficiency. Therefore, ways to design dye molecules with excellent photoelectric properties has been the focus of dye-sensitized solar cells research. Here, we selected four representative different metal-corrole monomers to characterize their structures and photoelectronic properties. Then based on these metal-corrole monomers, six different architectures of metal-dicorroles were designed by varying the linking forms. The most stable architecture [Formula: see text] was screened out by binding energy calculations. A further two types of metal-dicorrole-based dyes were constructed by incorporating different bridge groups with the cyanoacry acceptor into the stable metal-dicorroles. A large number of density functional theory calculations and photoelectric properties analysis indicate that among these different metal-dicorrole-based dyes, Ga-dicorrole dyes have two strong and wide absorption bands in the visible region corresponding to Soret and Q bands, respectively, and have high charge separation efficiency under optical excitation. Especially for Ga-SN dye, by incorporating a [Formula: see text]-bridge-conjugated group, its Soret absorption band is greatly enhanced, broadened and red-shifted, resulting in its merging with the Q band into one absorption band. Moreover, its charge transfer efficiency is up to 76.86%, which will facilitate its coupling with semiconductor materials and transfer its electrons to the semiconductor materials.

The relationship between cutoff charge-voltage and lithium-ion battery performance is very complex. This paper explores the influence of cutoff charge-voltage on lithium manganite (LMO)/lithium titanate (LTO) power lithium-ion battery for power application performance. Performance criteria evaluated include: low-temperature discharge capacity, pulse power density, and high temperature cycle life. Results illustrate that a lower cutoff charge-voltage (3.0 V) resulted in a battery with high discharge capacity at low temperature while a higher cutoff charge-voltage (3.8 V) in a battery leads to good high temperature cycle stability. A moderate cutoff charge-voltage (3.4 V) brought a battery with both high and low temperature-enhanced performance.

Aims Metformin was found to protect against hyperglycemia-induced injury in osteoblasts, but the cellular mechanisms involved remain unclear. Therefore, the aim of this study was to determine the effect of metformin on hyperglycemia-induced apoptosis and differentiation suppression in osteoblasts and to explore its relationships with the TLR4 signaling pathway. Main methods A mouse osteoblast cell line, MC3T3-E1, and a diabetic rat model were used to survey the protective effects of metformin on hyperglycemia-induced injury. TLR4 expression was altered using small interfering (si)RNA and lentivirus-mediated TLR4 overexpression. LPS was used as a specific TLR4 activator, and CLI-095 was used as a TLR4 inhibitor. Key findings Metformin improved osteoblast differentiation, reduced apoptosis in hyperglycemic osteoblasts, and inhibited TLR4, MyD88 and NF-κB expression in a dose-dependent manner. Down-regulating the expression or inhibiting the activity of TLR4 enhanced these protective effects of metformin on osteoblast differentiation, cell viability and cell apoptosis in hyperglycemic conditions, whereas up-regulating the expression or activating the activity of TLR4 had the opposite effects. Activating NF-κB suppressed the protective effects of metformin, while inhibiting NF-κB activity had the opposite effects. Metformin increased ALP and OCN secretion, enhanced BMP-2 expression, improved bone mineral density (BMD), and decreased TLR4, MyD88 and NF-κB levels in the femur tissues of diabetic rats. Significance Taken together our experimentation support the hypothesis that metformin may alleviate hyperglycemia-induced apoptosis and differentiation suppression in osteoblasts by inhibiting the TLR4/MyD88/NF-κB signaling pathway.

Polyquaternium-6 (PQ6) as the water-soluble polymer was used for complexing the anion forms of tungsten (VI) before ultrafiltration. Tungsten (VI)-PQ6 complex was retained by polysulfone hollow fiber ultrafiltration membrane in the complexation-ultrafiltration process. Effects of various operating parameters such as polymer metal ratio(PMR), pH and chloride ion concentration on permeate flux ( J ) and tungsten rejection coefficient ( R ) were investigated. The integration of four experiments including concentration, decomplexation, diafiltration and reuse of regenerated polymer was carried out. In the process of concentration, J declines slowly and R is about 1 at PMR of 3 and pH of 7. Tungsten concentration in the retentate increases linearly with volume concentration factor. Tungsten is concentrated efficiently with the membrane. The concentrated retentate was used further for the decomplexation. It takes about 6 min to reach the decomplexation equilibrium at chloride ion concentration of 50 mgL −1 . The decomplexation percentage of tungsten (VI)-PQ6 complex reaches 56.1%. In the diafiltration process, tungsten (VI) can be extracted effectively by using 50 mgL −1 chloride ion solution, and the purification of the regenerated PQ6 is acceptably satisfactory. The regenerated PQ6 was used to bind tungsten (VI) at various pH values. The binding capacity of the regenerated PQ6 is close to that of fresh PQ6, and the recovery percentage of binding capacity is higher than 90%.

This study was carried out to evaluate the effect of cigarette smoke (CS) on the activity of oral peroxidase (OPO) after berberine was added to the cigarette filter. Activated carbon fiber (ACF) was chosen to load berberine as a part of the cellulose acetate (CA) filter to obtain the modified B-ACF cigarette filter. Then the effects of CS from the testing cigarettes on the activity of OPO were investigated in vitro by the 2-nitrobenzoic acid assay, and the smoke chemistry was also analyzed, especially the content of hydrogen cyanide (HCN) in the CS. The results indicated that the loss of activity of OPO in B-ACF filter cigarette group decreased by 20% and 25%, compared with those of ACF and CA filter cigarette groups, respectively. The relative residual activity of OPO in B-ACF filter group was increased with the increase of berberine in the filter compared with the CA filter group. It could be observed that the reduction in HCN might be related to the berberine in the cigarette filter, reducing the inhibition of CS on the activity of OPO.

The microfiltration process of solvent naphtha 200 containing impurities was studied using multichannel ceramic membranes with pore diameters of 0.5 and 0.8 μm. The effects of operating time, transmembrane pressure, cross-flow velocity, and temperature on permeate flux and rejection were investigated. The scanning electron microscop and energy dispersive spectrometry were conducted for the clean and fouled membranes. Effect of backflushing on permeate flux was also studied. Results show that it is possible to recover over 94 % of the original flux by a program of backflushing. A concentration process was carried out and furthermore, various membrane resistances were calculated. Finally, commercial detergent, HNO 3 , and NaOH + NaClO cleaning stages were used for the 0.5-μm membrane.

Using the tools of modern molecular biology, we probe the interaction of nanotubes on silicon chips with proteins via combinatorial phage display methods. By screening against a large library of ra...

Analytic calculations of electron transport across a Schottky barrier in 6H–silicon carbide are presented. The treatment includes the effect of barrier height fluctuations and image charge lowering on both the thermionic emission and electron tunneling processes. The results show that barrier height inhomogeneities are very important, and can lead to reverse current densities that are orders of magnitude higher than obtained from a simple theory. Formation of detrimental filamentary currents are predicted. The results are in very good agreement with published experimental data at 300 K. Finally, under forward biasing conditions, the analytical theory yields ideality factors of 1.037 in close agreement with measurements.

Single-molecule enzymology allows scientists to examine the distributions of kinetic rates among members of a population. We describe a simple method for the analysis of single-molecule enzymatic kinetics and provide comparisons to ensemble-averaged kinetics. To isolate our model enzyme, alpha-chymotrypsin, into single molecules, we use an array of cylindrical poly(dimethylsiloxane) wells 2 microm in diameter and 1.35 microm in height. Inside the wells, a protease assay with a profluorescent substrate detects alpha-chymotrypsin activity. We hold the concentration of alpha-chymotrypsin at 0.39 nM in a given well with an enzyme-to-substrate ratio of 1:6,666 molecules. Fluorescence emitted by the substrate is proportional to enzyme activity and detectable by a charge-coupled device. This method allows for the simultaneous real-time characterization of hundreds of individual enzymes. We analyze single-molecule kinetics by recording and observing their intensity trajectories over time. By testing our method with our current instruments, we confirm that our methodology is useful for the analysis of single enzymes for extracting static inhomogeneity.