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Conjugated polymers (CPs) as photocatalysts have evoked substantial interest. Their geometries and physical (e.g., chemical and thermal stability and solubility), optical (e.g., light absorption range), and electronic properties (e.g., charge carrier mobility, redox potential, and exciton binding energy) can be easily tuned via structural design. In addition, they are of light weight (i.e., mainly composed of C, N, O, and S). To improve the photocatalytic performance of CPs and better understand the catalytic mechanisms, many strategies with respect to material design have been proposed. These include tuning the bandgap, enlarging the surface area, enabling more efficient separation of electron–hole pairs, and enhancing the charge carrier mobility. In particular, donor–acceptor (D–A) polymers were demonstrated as a promising platform to develop high-performance photocatalysts due to their easily tunable bandgaps, high charge carrier mobility, and efficient intramolecular charge transfer. In this minireview, recent advances of D–A polymers in photocatalytic hydrogen evolution are summarized with a particular focus on modulating the optical and electronic properties of CPs by varying the acceptor units. The challenges and prospects associated with D–A polymer-based photocatalysts are described as well.

Low temperature self-propagating forming coating material system for aluminum alloy cylinder parts was designed with Al, Fe2O3, Mo, Cu, Ni and Ti powders as raw materials. Low temperature self-propagating wear-resistant coating was prepared on the inner wall of aluminum alloy cylinder parts by thermal spraying ignition condensation centrifugal self-propagating fusion technology. XRD, DSC and SEM were used to study the microstructure, thermodynamic properties and cross-section morphology of the coating after thermal reaction of four kinds of low-temperature self-propagating materials with different proportions. The preparation process parameters of the coating were optimized by orthogonal test, including the amount of coating, the rotation speed of self-propagating centrifuge and the reaction time of self-propagating coating. The results show that the addition of Si, Mo and Zn powders in the four low temperature self-propagating powder systems can reduce the occurrence temperature of aluminothermic reaction; the optimal process parameters for coating preparation are rotational speed of 2000r/min, powder filling amount of 0.9g/cm3 and rotational reaction time of 16S.The results show that the coating with 20wt.% Al, 60wt.% Fe2O3, 12wt.% Si, 4wt.% Mo and 4wt.% Zn has better density and interface adhesion.

In this contribution, we developed a simple, scalable, and universal strategy to exfoliate conjugated porous polymers (CPPs) into 2D nanosheets. A series of pyrenyl (Py)-, benzene (B)-, thienyl (T)-, thieno[3,2-b]thiophene (Tt)- and dithieno[3,2-b:2′,3′-d]thiophene (Ttt)-based CPPs were facilely exfoliated into 2D ultrathin sheets with a thickness of 5–18 nm in reasonable yields of 6–20% upon sonication in N-methyl pyrrolidone. Owing to more exposed active sites and shorter migration distances of charge carriers, the photocatalytic hydrogen production rate of the CPP 2-D nanosheets is 1.5–20 times higher than those of their bulk counterparts. The current study represents the first systematic report on the solvent-assisted exfoliation of CPP materials to produce 2D ultrathin lamellae from bulk CPPs with common structures, which might provide new possibilities for the practical application of 2D CPPs.

Semiconductor heterojunctions benefiting from efficient charge transfer and separation have been widely used in photocatalysis. Herein, heterojunctions based on polymeric and inorganic semiconductors, namely PyOT@TiO2, have been successfully constructed via in situ C–H activation polycondensation of the pyrene unit (Py-) and 3-(2-(2-ethoxyethoxy)ethoxy)thiophene unit (-OT) in the presence of titanium dioxide (TiO2). The combination of the polymeric semiconductor PyOT with TiO2 not only broadens the light response of TiO2, but also dramatically promotes the photo-generation exciton separation of PyOT. As a result, the optimized 50% PyOT@TiO2 composite exhibited extensive visible light absorption (400–520 nm) and the highest photocatalytic hydrogen evolution rate using ascorbic acid (AA) as the sacrificial agent, which is approximately 135 and 21 times higher than those of single-components TiO2 and PyOT, respectively. Mechanistic study by XPS, M–S plots and hydroxyl radical detection tests revealed the p–n heterojunction characteristics of PyOT@TiO2 that contributed to the enhanced photocatalytic performance. Our work develops a promising strategy for the in situ construction of polymeric–inorganic soft–hard heterostructures via atom-economic C–H activation polymerization.

How to prompt higher photocatalytic hydrogen production (PHP) efficiency from water to achieve practical applications still remains a big challenge with conjugated porous polymers (CPP)-based photocatalysts. Herein, we developed a simple and efficient cosolvent-assisted strategy to significantly improve the photocatalytic efficiency of CPP-based photocatalysts by introducing water-soluble aprotic bipolar co-solvents, including N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), and N-methyl pyrrolidone (NMP). The PHP activity of the pyrene–bithiophene-based CPP (named CP-St) using ascorbic acid (AA) as a sacrificial electron donor could be excellently accelerated in the presence of an aprotic bipolar NMP solvent. CP-St dispersed in an NMP/H2O/AA mixed solution under visible-light (λ > 420 nm) irradiation without the aid of a Pt cocatalyst achieved an unprecedented hydrogen evolution rate (HER) of 190.7 mmol h−1 g−1. As a result, 6 mg CP-St amazingly produced 128.1 mL H2 (∼5.72 mmol) under visible-light irradiation for only 5 h. Excitingly, by introducing 0.5 wt% Pt cocatalyst into the NMP/H2O/AA system, the HER of CP-St could be further boosted to 303.7 mmol h−1 g−1 (1.82 mmol h−1/6 mg), which represents the highest photocatalytic HER ever reported. This outstanding photocatalytic performance is mainly ascribed to the enhanced dispersity, strong hydrogen-bond interactions, and exfoliation effect by the NMP solvent. This study provides us with some new design ideas and opportunities for effectively catering to the actual hydrogen production demand.

In the development of Nb3Sn superconducting strands, the improvement of the non-Cu critical current density ( $J_{{\rm{c}}}$ ) has been greatly emphasized. Different Nb3Sn strands were manufactured by the bronze route artificially doped with titanium in bronze. The influences of bronze on Nb volume ratio, filament material, filament diameter, and heat treatment were studied. In this paper, bronze-to-Nb volume ratio affected $J_{{\rm{c}}}$ slightly due to the formation of the Sn shortage and similar Nb3Sn volume after heat treatment. The study of filament diameter indicates that $J_{{\rm{c}}}$ increases largely as the filament diameter reduces for the full reaction. Different heat treatment times at 575 °C, 650 °C, and 675 °C will result in various performances. According to microstructure images, residual Nb core can be seen in each filament. Bigger average grain size will lead to lower $J_{{\rm{c}}}$ .

While testing a deep exploratory well located in Bohai bay in China, a large amount of carbon dioxide (CO 2 ), hydrogen sulfide (H 2 S) and carbon monoxide (CO) was detected unexpectedly. Being afraid of their corrosiveness and toxicity, testing work was terminated immediately. After tripped out, the string was found to have been eroded severely. In order to keep going the exploratory work, experiment was made to investigate corrosion rate of carbon steel in environment with multiple deleterious substances. A main purpose was to determine if carbon monoxide has a strong impact on anti-sulfide steel P110S, which is low-cost and has been widely used in sour wells. Experiment result indicates that carbon monoxide has no obvious influence on corrosion rate in circumstances that carbon dioxide and hydrogen sulfide exist. Comprehensive studies show that P110S tubing can be used as testing string to carry out down-hole work. These results eliminated worries of decision-makers.

The wetting behavior of polymer melts such as HDPE, PP, PC, POM and COC on bulk metallic glass material substrates that are used in polymer micro fabrication like micro injection molding was investigated by sessile drop method at a temperature above the corresponding melting temperatures. Contact wetting angles have been determined on three kinds of bulk metallic glasses: Pd40Cu30Ni10P20, Zr64.8Cu15.5Al8.3Ni11.4and La57.5Al17.5Ni12.5Cu12.5. The equilibrium contact angle has the monotone decrease with the increasing temperature for most polymer melts. Two kinds of wetting behaviors are observed, spanning from 126°, over neutral wetting, to 6°, almost complete wetting. Estimations of the contact wetting angles are presented in different polymer melt temperature. Optimization of process parameter can be chosen according to the wetting ability.

Solutions of lyotropic cholesteric liquid crystalline hydroxypropyl cellulose (HPC) in water would be self-colored due to the selective reflection of visible light, depending on the solution concentration. Colored coating of the liquid crystalline aqueous HPC solutions was attempted to apply. HPC solid films were found which could cast from the liquid crystalline solutions at different conditions such as solution concentration and different drying temperature. Experiments show that both solution concentration and cooling velocity play an important effect in controlling the color of HPC films.

In our study, a new kind of water treatment composite was prepared by melt blending and molding foaming, with synthetic rubber EPDM as the matrix, graphite oxide modified glass fiber (GF) as the filler. The foamed composite had a certain adsorption capacity of methylene blue dye in the water and toluene. With the increase of the graphite oxide modified GF, the composite on the methylene blue adsorption rate was increased, however, for toluene, the rate of adsorption was reduced. Due to restrictions on the oxidation of graphite and composite structures and the adsorption capacity of the material was limited.

In this study, a new composite was prepared for aniline adsorption by melt blending with EPDM as the matrix and natural zeolite was modified by microwave as the filler. The properties and some influential factors of composite for adsorption of aniline in the solutions were experimentally investigated, such as composite dosage, adsorption time and pH values. The results showed that in the case of the initial concentration of the aniline wastewater was 50mg/L, when the use level of composite was 1 g, pH value was 1, and the oscillating adsorption time was 2 h, the removal rate could be up to 92%.

In our study, a new kind of material for toluene adsorption was prepared by melt blending with EPDM as the matrix and waste dusty slag as the filler. The effects of dicumylperoxide (DCP) and waste dusty slag contents on the toluene absorbency were studied. The results show that the toluene absorbency reaches the highest value 388.11 % for the composite with 2 wt % DCP and 30 wt % waste dusty slag. Comparing the toluene absorbency for three samples, the experimental result indicates that the toluene absorbency of waste dusty slag /EPDM composite was higher than that of EPDM (crosslinked) and EPDM

In our study, a new kind of material for Copper (Cu2+) absorbency was prepared by melt blending with EPDM as the matrix and modified zeolite as the filler. In order to overcome this obstruction, PEG-2000 was used as pore forming agent. By calculating, trial parameter n was 1.9, so, the composite was easy absorption. By SEM and XRD measurement, it was confirmed that the composite was more suitable as filler than the original zeolite and the acid modified zeolite. It can be showed that the pore forming agent adding was necessary and effective for the absorption by SEM micrograph of suction passage in EPDM and the composite.

In our study, a new kind of NH4+ sewage water treatment composite was prepared by melt blending, with synthetic rubber EPDM as the matrix, modified fly ash as the filler. The removal rate of NH4+ increased with increasing pH (The range of pH investigated was 2.0-5.0.), the removal rate of NH4+ decreased with increasing pH (The range of pH investigated was 5.0-9.0.); increasing temperature made against the adsorption, “Room temperature” is the optimum temperature; the removal rate of NH4+ increased with increasing adsorption composite content. When the adsorption reached equilibrium, the removal rate was remain unchanged.

Fungi are an integral component of the plant microbiome. However, the composition and variation in the fungal communities (mycobiota) associated with seeds are poorly understood. In this study, we investigated the mycobiota of 11 maize seed samples with storage times ranging from 6 months to 12 years. Mycobiota were characterized by a culture‐based approach, and fungal species were identified through rDNA‐ITS sequence analyses. From a total of 169 pure fungal isolates obtained from both the seed surface and internal tissues, we identified 16 distinct species (belonging to 10 genera) associated with maize seeds, all but one of which were ascomycetes. Among these species, seven were exclusively isolated from internal tissues, two species were isolated only from the seed surface, and another six species were isolated from both the surface and internal tissues. Aspergillus niger was consistently found under all storage conditions and dominated fungal communities with a relative abundance of 36%–100%. Species of Fusarium (9%–40%) and Penicillium (9%–20%) were also frequently isolated, but other species appeared sporadically and were isolated from fewer than three seed stocks. According to our results, while the overall incidence of fungal infection generally declined with storage time, there was no consistent association between seed storage time and fungal species richness or relative abundance; furthermore, the composition of the mycobiota associated with maize seeds was highly variable among the samples. The detection of the four major mycotoxigenic fungal genera, specifically Aspergillus, Fusarium, Penicillium, and Alternaria, was alarming, and the isolation of a potential controlling agent as well as information about their temporal occurrence will contribute to the management of mycotoxins in the future.

The elastic resonance scattering of 12C+p has been studied in inverse kinematics via a novel thick target method at GIRAFFE facility of HI-13 tandem accelerator laboratory, Beijing. The recoil protons were measured by a ΔE-E counter telescope based on a large area double-sided silicon strip detector at laboratory angles around θ0 = 15°. The excitation function for 12C(p,p) elastic scattering has been obtained over a wide energy range of Ec.m.=0.31–3.45 MeV, which was explained quite well by the R-matrix calculation with known resonance parameters of the first three levels in 13N nucleus. Thus it is demonstrated that the present setup can be directly applied to the study of elastic resonance scattering with secondary radioactive beams.

In our study, a new kind of material for toluene adsorption was prepared by melt blending with EPDM as the matrix and waste dusty slag as the filler. By considering the influence of pH, temperature, stirring speed on adsorption capacity. The results showed that the environmental pH has little effect on the toluene absorbency of the composite; “Room temperature” is the optimum temperature; increased the stirring speed can reduce the adsorption time.

Three new purine derivatives, namely, 4-caryboxy-5,6-dihydro-4H,8H-pyrimido[1,2,3-cd]purine-8,10(9H)-dione (1), 7,9-dihydro-1-(3-oxobutyl)-1H-purine-6,8-dione (2), and 7-hydro-9-(3-oxobutyl)-1H-purine-6,8-dione (3) together with six known purine and pyrimidine derivatives were isolated from the EtOH/CH2Cl2 extracts of the South China Sea gorgonian Subergorgia suberosa. The structures of 1—3 were determined on the bases of extensive spectroscopic analysis, including 1D and 2D NMR data.

BaGe1.51, hexagonal, P6/mmm (no. 191), a = 4.458(2) A, c = 4.867(3) A, V = 83.78(6) A, Z = 1, Rgt(F) = 0.0132, wRref(F ) = 0.0292, T = 293 K. Source of material BaGe1.51 is the by-product of a reaction to synthesize Ba2LixMg2–xGe3 which realises the Sr2Mg2-xSi3 structure-type [1]. Amixture of the pure elements at stoichiometric amountswas heated up to 1123 K for 12 h. After cooling down at a rate of 50K/h, the productwas obtained as dark grey crystalswithmetallic lustre. The compound is air and moisture sensitive. Experimental details In the structure, the occupancy of germanium site was also refined. Discussion BaGe1.51 crystallizes with the AlB2 [2] structure type. The structure refinement indicates that the germanium sites (Wyckoff symbol: 2d) are not fully occupied. Every Ge atom is coordinated by a trigonal Ba6 prism respectively, forming a planar layer of six rings. Every barium atom is in the center of a hexagonal prism of Ge atoms. In contrast to the CaGaSi structure in which a torsion angle of 13° is observed [3], the U33 parameters of the Ge atoms do not show any apparent distortions of the layer. TheGe–Ge–Ge bond angle is 120°, and the bond length forBa–Ge is 3.5423(1)A, for Ge–Ge bond is 2.5741(1) A, which are all in a reasonable region. Z. Kristallogr. NCS 228 (2013) 441-442 / DOI 10.1515/ncrs.2013.0207 441 © by Oldenbourg Wissenschaftsverlag, Munchen Crystal: grey plates, size 0.08#0.10#0.12 mm Wavelength: Mo K0 radiation (0.71073 A) +: 248.19 cm Diffractometer, scan mode: SMART PLATFORM CCD Detector, # 2)max: 61.12° N(hkl)measured, N(hkl)unique: 1126, 75 Criterion for Iobs, N(hkl)gt: Iobs > 2 &(Iobs), 75 N(param)refined: 7 Programs: SHELX [4], ATOMS [5] Table 1. Data collection and handling. _____________ * Correspondence author (e-mail: qxxie@yahoo.com) Unauthenticated Download Date | 3/26/16 8:02 AM

Three new purine derivatives, namely, 4-caryboxy-5,6-dihydro-4H,8H-pyrimido[1,2,3-cd]purine-8,10(9H)-dione (1), 7,9-dihydro-1-(3-oxobutyl)-1H-purine-6,8-dione (2), and 7-hydro-9-(3-oxobutyl)-1H-purine-6,8-dione (3) together with six known purine and pyrimidine derivatives were isolated from the EtOH/CH(2)Cl(2) extracts of the South China Sea gorgonian Subergorgia suberosa. The structures of 1-3 were determined on the bases of extensive spectroscopic analysis, including 1D and 2D NMR data.