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Constructing a heterojunction to extend the survival time of photogenerated carriers is an effective way to increase the photocatalytic performance of materials. The 2D-2D flower-like DUT-5@Bi2WO6 composite material is obtained via the hydrothermal method for the frist time. The efficiency of Rhodamine B removal based on 30% DUT-5@Bi2WO6 is 87% under visible light for 18 min, which is 4.55 times that of pure Bi2WO6. RhB-sensitized effect plays a decisive role in enhancing the photocatalytic activity of DUT-5 to RhB under visible light. The results shows that the type I heterojunction is formed between RhB/DUT-5 and Bi2WO6. The wide contact surface stems from heterojunction can accelerate the separation and transfer of photo-generated charges. Furthermore, the high specific surface area and unique pore structure of DUT-5 provide sufficient active sites for photocatalytic reactions. Thus, the efficient charge transfer and sufficient active sites contribute to the photocatalytic activity. This work provides a new idea for the development of 2D-2D composite materials to degrade organic pollutants under visible light to solve environmental pollution.

In this work, the solubilities of carbamazepine (CBZ) (form III) in ethyl acetate, methyl acetate, ethylene glycol, chloroform and cyclohexylamine were determined by laser monitoring techniques at pressure above sea level, and the solubility data of CBZ (form III) in different pure solvents were fitted by the Modified Apelblat model and λh model. The result shows that the solubility of CBZ (form III) in five solvents increases as temperature rises, and the solubility in chloroform was the largest. The experimental solubility values of CBZ (form III) in ethyl acetate, methyl acetate, chloroform and cyclohexylamine were in better agreement with the simulated fitting values of the λh model. For ethylene glycol, the σ value was much larger than the other four solvents, and it can be seen from the λh model that ethylene glycol was closer to the ideal solution system than the other four solvents.

Realgar is a traditional Chinese medicine that contains arsenic. It has been reported that the abuse of medicine containing realgar has potential central nervous system toxicity, but the toxicity mechanism has not been elucidated. In this study, we established realgar exposure model in vivo and selected DMA, the end product of realgar metabolism, to treat SH-SY5Y cells in vitro. Many assays including behavioral, analytical chemistry, and molecular biology were used to elucidate the roles of autophagic flux and p62-NRF2 feedback loop in realgar-induced neurotoxicity. The results showed that arsenic could accumulate in the brain, causing cognitive impairment and anxiety-like behavior. Realgar impairs the ultrastructure of neurons, promotes apoptosis, perturbs autophagic flux homeostasis, amplifies the p62-NRF2 feedback loop, and leads to p62 accumulation. Further analysis showed that realgar activates JNK/c-Jun, promotes the formation of Beclin1/Vps34 complex, induces autophagy, and recruits p62. Meanwhile, realgar inhibits the activities of CTSB and CTSD, and changes the acidic of lysosomes, resulting in the inhibition of p62 degradation, and then accumulation. Moreover, the amplified p62-NRF2 feedback loop is also involved in the accumulation of p62. Its accumulation promotes neuronal apoptosis by up-regulating the expression levels of Bax and cleaved-caspase-9, resulting in neurotoxicity. Taken together, these data suggest that realgar can perturb the cross-talk between autophagic flux and the p62-NRF2 feedback loop to mediate p62 accumulation, promote apoptosis, and induce neurotoxicity.

Halophilic α-amylases possess optimal activity in high salt concentrations. Therefore, they can be used in many extreme conditions in industrialised production. In the present work, a halophilic α-amylase (KP) from Klebsiella pneumoniae was characterised, and it exhibited a high specific activity of 3512 U/mg under optimal conditions of 2 M NaCl at 50°C and pH 6.5, but only 97 U/mg in the absence of salt. Furthermore, threonine at position 329 (Thr-329) was found to be related to the non-halophilic properties of KP according to PCR-based site-saturation mutagenesis. The activity of a mutant KP in which this threonine was replaced by aspartic acid was improved 14.6-fold compared with the native enzyme under salt-free conditions, and was increased by 14.8% in the absence of salt. Additionally, the optimal enzymatic properties of KP, including pH and temperature, were altered very little by the amino acid replacement. A further three halophilic α-amylases displayed similar mutational results. The findings provide a reference for bidirectional transformation of KP and similar halophilic enzymes.

Nano-scale MOF composite materials prepared by combining inorganic semiconductors with controllable pore structures and functional active sites for the effective removal of organic dyes will exhibit more excellent adsorption activity. In this paper, MIL-101(Cr) was used as a carrier and two-step hydrothermal methods were successfully used to prepare flower-like TiO2/MIL-101(Cr) composite nano-adsorbents with different sizes. The results of XRD, SEM, XPS and other characterization methods showed that when the molar ratio of Ti : Cr was 0.2 : 1, the composite nano-adsorbent exhibited better adsorption performance and removal efficiency for methyl orange (MO) in aqueous solution. By assembling TiO2 on MIL-101(Cr), Ti replaced part of Cr, and the positively-charged TiO2/MIL-101(Cr) nanocomposite and negatively-charged MO in aqueous solution formed a strong interaction force. In addition, the π–π packing interactions of the benzene ring of MIL-101(Cr) and the electrostatic force between TiO2 and MIL-101(Cr) also enhanced the performance and adsorption efficiency of the adsorbent to a certain extent. The BET results showed that the large specific surface area and average pore diameter of the TiO2/MIL-101(Cr) nanocomposites effectively improved the adsorption performance of the composites. The results showed that the MO removal efficiency of 20% TiO2/MIL-101(Cr) can reach 93.03% at 80 min. But when 20% TiO2/MIL-101(Cr) was used to adsorb 70 mg·L−1 MO, the experimental maximum adsorption capacity was 242.02 mg·g−1.

Hepatitis B surface antigen (HBsAg) clearance is significantly more common in children with chronic hepatitis B (CHB) than in adults; however, the possible influencing factors related to HBsAg loss have yet to be found. This study aimed to explore the efficacy of long-term interferon (IFN)α therapy in treating children with CHB and analyzed the factors influencing functional cure after treatment.A total of 236 children aged 1-6 years and diagnosed with CHB via liver biopsy were included in the study, all receiving IFNα treatment (IFNα-2b monotherapy, IFNα-2b followed by lamivudine [LAM] or IFNα-2b combined with LAM) and followed up for 144 weeks. A comprehensive analysis was conducted on clinical data, including biochemical items, serum markers of hepatitis B virus (HBV) and immunological indexes, and logistic regression analysis was used to screen the influencing factors related to HBsAg loss.The cumulative loss rates of HBsAg were 79.5%, 62.1% and 42.1% at 144 weeks after the start of treatment in the 1-3 years-old group, 3-5 years-old group and 5-7 years-old group, respectively (Long-term treatment with IFNα was effective in achieving HBsAg loss in CHB children aged 1-6 years-old. Age less than 3 years-old and lower HBsAg levels are independent predictors of functional cure in children with CHB.

Nano-scale MOF composite materials prepared by combining inorganic semiconductors with controllable pore structures and functional active sites for the effective removal of organic dyes will exhibit more excellent adsorption activity. In this paper, MIL-101(Cr) was used as a carrier and two-step hydrothermal methods were successfully used to prepare flower-like TiO

Construction of heterojunction is an effective way to improve the photocatalytic activity of photocatalyst. In this work, a simple precipitation method was adopted to anchor rod-like AgVO3 on Bi4Ti3O12 nanosheets to form heterojunction. The results show that Ag can act as an electronic medium to construct Z-scheme heterojunctions, that more visible light can be absorbed and facilitates the separation of electron hole pairs compared with the pure Bi4Ti3O12. The AgVO3/Bi4Ti3O12 composites displayed superior photocatalytic photodegradation of tetracycline (TC) under visible irradiation (λ > 420 nm). 12%AgVO3/Bi4Ti3O12 (AgVO3 with the mass ratio of AgVO3/Bi4Ti3O12 = 12%) showed the highest photocatalytic degradation efficiency, 57% of TC was degraded within 60 min which was the 9.5 times and 2.5 times higher than pure AgVO3 and Bi4Ti3O12. The capture experiment results showed that ·O2− and h+ are the main active radicals in the process of TC degradation. The improved photocatalytic activity is attributed to the construction of Z-scheme heterojunction, which leads to expand the light absorption range and efficient separation of photogenerated carriers. In addition, the mechanism of the photocatalytic degradation of antibiotics was proposed.

Radio-fluorogenic (RFG) gels become permanently fluorescent when exposed to high-energy radiation with the intensity of the emission proportional to the local dose of radiation absorbed. An apparatus is described, FluoroTome 1, that is capable of taking a series of tomographic images (thin slices) of the fluorescence of such an irradiated RFG gel on-site and within minutes of radiation exposure. These images can then be compiled to construct a 3D movie of the dose distribution within the gel. The historical development via a laboratory-bench prototype to a readily transportable, user-friendly apparatus is described. Instrumental details and performance tests are presented.

The performance of an efficient denitrification bioreactor–aerobic biofilm reactor cascade for heavy oil refinery wastewater treatment was investigated. Optimum operation parameters for denitrification were found as follows: (1) hydraulic retention time of 8 h; (2) C/NO3−–N molar ratio of 3.75 with acetate as the carbon source; (3) 20% (v/v) carrier filling ratio in the denitrification bioreactor. Under such optimal conditions, a volumetric removal of 0.82 kg N m−3 d−1 was obtained. As an alternative low-cost carbon source to acetate, secondary DAF effluent (COD/NO3−–N mass ratio of 5.4) was also detected and a stable activity of denitrification was achieved with adding 25% volume fraction of secondary DAF effluent. Effluent COD of the subsequent aerobic biofilm reactor further decreased satisfying the requirements of the current discharge standards. High-throughput sequencing results exhibited that Rhodocyclaceae and Comamonadaceae were the dominant denitrifiers in the denitrification reactor and Pseudomonas was the dominant microbe in the aerobic biofilm reactor.

The solid-liquid phase equilibrium solubility of Doxofylline was measured and discussed in ten pure organic solvents and co-solvent mixtures of acetonitrile + ethanol (+or water) at temperature range from 278.15 to 323.15 K. Results indicated that experimental mole fraction (x) of Doxofylline in ten neat solvents followed this order: acetonitrile > tetrahydrofuran > benzene > acetone > ethyl acetate > methanol > 1-propanol ≈ 2-propanol > ethanol ≈ water, and solubility increased with temperature increasing. Moreover, experimental solubility of Doxofylline firstly increased and then declined with the mass fraction increasing of acetonitrile in acetonitrile + ethanol (+or water) mixture solvents at each temperature. Hansen solubility parameter and solvent effect were used for explaining and discussing solubility rule of Doxofylline in selected solvents. Model correlation indicated the NRTL model was the most suitable than other models to predict solubility of Doxofylline in pure solvents and Sun model was better than other models in mixture solvents with accompanied by temperature and composition. Furthermore, thermodynamic properties of standard molar enthalpy, molar Gibbs free energy and molar entropy in solution was calculated and discussed.

The detection of organophosphorus pesticides (OPs) has received considerable attention for their great harm to human beings. Herein, a novel ratiometric fluorescence biosensor was constructed for the determination of OPs by using Scopoletin (SC) and Amplex Red (AR) as probe pairs that have opposite responses to MnO2 nanosheets (MnO2 NS). MnO2 NS possess peroxidase-like catalytic activity, which could quench the fluorescence of SC as well as enhance the fluorescence of the non-fluorescent substance AR by oxidation. In the absence of OPs, acetylcholinesterase (AChE) hydrolyzed acetylcholine chloride (ATCh) into choline (TCh) and acetate. TCh led the decomposition of MnO2 NS to manganese ions (Mn2+), increasing signal of SC and decreasing signal of AR. In the presence of OPs, the activity of AChE was inhibited and the decomposition of MnO2 NS was hindered, therefore the fluorescence intensity of SC was weak and the fluorescence intensity of AR had an obvious increase. Moreover, under the optimal conditions, the ratio of fluorescence intensity response recorded on the AR/SC increases with increasing the concentration of DDVP. The method has wider linear range of 5.0 pg/mL ∼500 ng/mL with a detection limit of 1.6 pg/mL, which is superior to previously reported methods. This strategy has also been applied to a visual observation based on the color change of the solution under UV light.

Four new homobinuclear lanthanide(III) complexes of multidentate 3-methyloxysalicylaldoxime (MeOsaloxH2), [Ln2(MeOsaloxH)4(PhCOO)2(CH3OH)2] (Ln = Pr, 1; Nd, 2; Sm, 3) and [Gd2(MeOsaloxH)4(CH3COO)2(H2O)2]·2H2O (4), have been synthesized and characterized by elemental analyses, IR spectroscopy and single-crystal X-ray diffraction. In these complexes, the two LnIII ions are bridged by two phenolate oxygens from two η1:η2:η1:μ2-[MeOsaloxH]- ligands and two carboxylate groups to form a [Ln2O2(RCOO)2] binuclear structure (R = Ph, 1-3; CH3, 4). The noncovalent interactions (hydrogen bonds and weak C-H···O interactions) led to two types of three-dimensional supramolecular architectures. Magnetic and luminescence properties of these complexes have also been studied.

We have measured the dose, D, and dose rate, D', dependences of the radiation-induced change in optical absorption of four radiochromic films currently used for (2D) dosimetry: GafChromic (R) types EBT3, MD-V3, HD-V2 and HD-810. We have irradiated the films using two Co-60 gamma-ray sources with dose rates of similar to 2 and similar to 30 Gy/min and a 200 kVp X-ray source with dose rates from similar to 0.2 to similar to 1.0 Gy/min. The 48-bit RGB image files of the films, obtained using an Epson V700 flatbed scanner, were color-channel separated and the red, green and blue"pixel levels, P(D), were determined using ImageJ software. The relationship P(D)/P(0)=[1+hD/m]/ [1+D/m] is found to provide a good description of the dose dependence for all four films at all dose rates. The parameter his the "plateau level" of P(D)/P(0) approached at high doses, i.e. P(infinity)/P(0). The parameter m is the "median-dose" for which P(D)/P(0)(1+h)/2 which is the half point in the dynamic range of the particular film. The best-fit values of m over the dose rate range from similar to 0.2 to similar to 25 Gy/min using the red pixels were 1.42 +/- 0.03, 11.1 +/- 0.4, 63.6 +/- 0.9 and 60.6 +/- 1.6 Gy for EBT3, MD-V3, HD-V2 and HD-810 respectively. Using the green pixels the median dose is 1.8 times larger for the first 3 films and 2.5 times larger for HD-810. The blue pixels are considered unsuitable for dosimetry because of the large value of h (>0.4) and the resulting small dynamic range.

The purpose of the present research was to provide a radiation-chemical basis for the use of tertiary-butyl acrylate gels in radio-fluorogenic dose-imaging applications ( Warman et al., 2011a , Warman et al., 2011b , Warman et al., 2013a , Warman et al., 2013b ). The radiation-induced polymerization of tertiary-butyl acrylate (TBA) results in the formation of a transparent gel with an optical density lower than 0.1 cm−1 from 600 nm down to 315 nm. The fractional monomer-to-polymer conversion, CM, determined gravimetrically, increases super-linearly with dose, D Gy. Up to CM≈40%, and over the dose rate range D′=3.5 to 49 cGy s−1, the dose dependence is given by CM=[1+ACM]KD/√D′ with K=1.43×10−3 Gy−0.5 s−0.5 and A=0.70. For D′=3.5 cGy s−1 the average polymer size is estimated to be 1.2×105 monomer units or 17 megadalton. For CM≥10% the gel is quasi-rigid, displaying little tendency to flow on a timescale of an hour or more. After removal of monomer by evacuation, the gel can be reformed by adding a volume of monomer to the remaining polymer equal to that removed and allowing this to swell for several days. The dose and dose rate dependence of radiation-induced monomer conversion in the reformed gel show no evidence of a discontinuity caused by the intervening evacuation and reformation procedures.

A new tetranuclear mixed-valence cobalt complex, namely di-μ2-azido-diazidodiethanolbis{μ2-2-[(hydroxyimino)methyl]-6-methoxyphenolato}bis{μ3-6-methoxy-2-[(oxidoimino)methyl]phenolato}dicobalt(II)dicobalt(III) ethanol disolvate, [CoII2CoIII2(C8H7NO3)2(C8H8NO3)2(N3)4(C2H5OH)2]·2C2H5OH, has been synthesized by the reaction of Co(OAc)2·4H2O (OAc is acetate) with 3-methoxysalicylaldoxime (H2mosao) in an ethanol solution. In the complex, the four Co cations all display distorted octahedral coordination environments and they are bridged by two κ2,κ1,κ1;μ3-mosao2−ligands, two κ2,κ2;μ2-Hmosao−ligands and two μ2-N3−anions to form a tetranuclear [Co4N4O4] cluster. Adjacent clusters are connected through weak C—H...N and C—H...O interactions, resulting in a two-dimensional supramolecular network parallel to theacplane. The magnetic properties of the complex have also been studied.

A fluorimetric Hg2+ test strip has been developed using a lotus-inspired fabrication method for suppressing the “coffee stains” toward the uniform distribution of probe materials through creating a hydrophobic drying pattern for fast solvent evaporation. The test strips were first loaded with the model probes of fluorescent gold-silver nanoclusters and then dried in vacuum on the hydrophobic pattern. On the one hand, here, the hydrophobic constraining forces from the lotus surface-like pattern could control the exterior transport of dispersed nanoclusters on strips leading to the minimized “coffee stains”. On the other hand, the vacuum-aided fast solvent evaporation could boost the interior Marangoni flow of probe materials on strips to expect the further improved probe distribution on strips. High aqueous stability and enhanced fluorescence of probes on test strips were realized by the hydrophilic treatment with amine-derivatized silicane. A test strips-based fluorimetry has thereby been developed for probing Hg2+ ions in wastewater, showing the detection performances comparable to the classic instrumental analysis ones. Such a facile and efficient fabrication route for the bio-inspired suppression of “coffee stains” on test strips may expand the scope of applications of test strips-based “point-of-care” analysis methods or detection devices in the biomedical and environmental fields.

The radiation-induced polymerization and fluorescence intensity of a radio-fluorogenic medium consisting of tertiary-butyl acrylate (TBA) with ca 100 ppm maleimidopyrene (MPy) display a super-linear dependence on dose and a close to inverse square root dependence on dose rate over the range from 2 to 30 Gy/min. In contrast with the fluorescence, the clarity and optical absorption remain unchanged on irradiation up to at least 17% monomer conversion for which the medium is a rigid gel.

In this work a 40 mm cube of an optically clear, radio-fluorogenic gel composed of partially-polymerized tertiary-butyl acrylate and maleimido-pyrene (similar to 0.01%) is irradiated with orthogonally-crossed, 10 mm square and round, 200 kVp x-ray beams. A thin sheet of UV light is produced between two parallel plates with 2 mm slits illuminated by collimated, linear-array, LED sources. The gel is transported 1 mm at a time through the UV sheet and the fluorescence from the emissive, polymeric radiolytic product formed in the x-ray tracks is recorded, as both JPEG and raw-DNG files, using a CCD camera placed orthogonal to the plane of the excitation light. The resulting stack of 40 tomographic slices are imported into freely-available software to produce 3D animated images of the radiation-induced fluorescence.