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Three new complexes, namely, [Cu2(H2bdcpb)2(pyridine)2] (1), [Cu3(bdcpp)2(CH3NCH3)(H2O)] (2), and [Cu2(H2bdcpp)2(H2O)2]·2H2O (3), have been synthesized through the hydro/solvothermal reaction of cu...

The microstructure，texture distribution and tensile property of 7xxx ultra-thick plate was investigated by optical microscopy (OM), scanning electron microscopy (SEM), electron back scattering diffraction (EBSD), transmission electron microscopy (TEM) and tensile tests. The results show that the microstructure, texture and tensile property were inhomogeneous along the thickness direction. A large number of sub-crystals remained on the surface of the thick plate and was accompanied by much recrystallization. Most of the structures were random texture, and the proportion of typical texture was low at the edge. For the center layer, there were also a lot of recrystallized grains and typical deformed texture along the β-fiber (Brass, S, and Copper) was observed. The 1/4 layer of the plate is a transition one, and had the lowest recrystallized fraction. From surface to center, precipitation phases within grains and grain boundaries gradually coarsen, mechanical properties reduced. At the same thickness, the tensile property showed appreciable anisotropy, the L direction was the highest and the S direction was the lowest.

Three new luminescent metal–organic frameworks (LMOFs), [Zn(tppa)(ndc)]n (1), [Cd(tppa)(oba)]n (2), [Zn2(tppa)(bpdc)2]n (3) (tppa = tri(4-pyridylphenyl)amine, ndc = 1,4-naphthalenedicarboxylic acid, oba = 4,4′-oxydibenzoic acid, bpdc = 4,4′-biphenyldicarboxylic acid) have been synthesized by solvothermal method. Complexes 1 and 2 are 2-D two-fold interpenetrating structures, aligning into a 3-D structure through C–H⋯π stacking interactions, while 3 is a 5-fold interpenetrating three-dimensional structure. The internal quantum yields (IQYs) of complexes 1–3 are 32.7%, 45.7% and 24.0% (λex = 365 nm), separately. Furthermore, all the complexes show different luminescence signal changes towards aromatic volatile organic compounds (AVOCs). Complex 1 exhibits a high sensitivity in the detection of both Fe3+ and Cr3+ with large quenching coefficients of Ksv 2.57 × 104 M−1 and 2.96 × 104 M−1, respectively. All these results demonstrated potential applications in chemical sensing.

The microstructure, texture distribution, tensile property and fracture toughness of 7A36 aluminum alloy profile were investigated by optical microscopy (OM), scanning electron microscopy (SEM), electron back scattered diffraction (EBSD), tensile and toughness tests, respectively. The results show that when extrusion temperature increased from 410 °C to 430 °C, the second phase grew and the intensity of aging state alloy increased. With the extrusion temperature increased, the fracture toughness and elongation increased firstly and the decreased. The fracture toughness KICcan reach to 46.47 MPa·m1/2 at 420 °C. The extruded and final state of the 7A36 profile was dominated by the textured texture (Brass, S, and Copper), accompanied by a small amount of recrystallized type texture (Cube and Goss). As the extrusion temperature increased, the hard deformation texture increased, resulting in an increase in strength. The increase of extrusion temperature led to the increase of dynamic recrystallization fraction. The dynamic recrystallization fraction of the extruded state was 2.26 % when extrusion temperature was 430 °C. The change in KIC performance is the combined result of re-crystallization, second phase and texture.

The luminescent complexes [Cd(BIMP)2(NDC)2]n and [Zn(BIMP)2(NDC)]n (where (3-BIMP) = 3-(1H-benzoimidazol-2-yl)pyridin-2(1H)-one and NDC = 2,6-naphthalenedicarboxylic acid) have been synthesised under hydrothermal conditions and their crystal structures determined. [Cd(BIMP)2(NDC)2]n exhibited a 1D → 2D → 3D framework structure and [Zn(BIMP)2(NDC)]n has a 3D porous structure. Under the same excitation energy (λex = 389 nm), [Zn(BIMP)2(NDC)]n showed a stronger fluorescence emission than the free 3-BIMP ligand, the NDC ligand and [Cd(BIMP)2(NDC)2]n.

This work takes the 36 cities from China's low-carbon pilot project as the research object and uses the carbon emission per capita and GDP per capita to categorize the 36 cities into four types to reveal their low-carbon development status; these four types are leading cities, developing cities, latecomer cities, and exploring cities. On the basis of an index system that quantitatively describes low-carbon development, this research analyzes the characteristics, development trends, and low-carbon development pathways of the four types of cities. According to the present situation and objectives of national emissions and considering the differences in development stages, challenges, and opportunities for each type of the city, this research presents recommendations for the low-carbon roadmap and the medium- and long-term (by 2030) emission trend routes of different types of regions in China. Keywords: City, Low-carbon development, Index evaluation, Development path

To enhance the heavy metal cation adsorption capacity of sewage sludge-derived biochar in an aqueous medium with a high concentration of Ca

Purpose – This paper aims to present a different cooling method (water cooling) to protect all the mechanical/electrical components for Tokamak in-vessel inspection manipulator. The method is demonstrated effective through high temperature experiment, which provides an economical and robust approach for manipulators to work normally under high temperature. Design/methodology/approach – The design of cooling system uses spiral copper tube structure, which is versatile for all types of key components of manipulator, including motors, encoders, drives and vision systems. Besides, temperature sensors are set at different positions of the manipulator to display temperature data to construct a close-loop feedback control system with cooling components. Findings – The cooling system for the whole inspection manipulator working under high temperature is effective. Using insulation material such as rubber foam as component coating can significantly reduce the environmental heat transferred to cooling system. Originality/value – Compared with nitrogen gas cooling applied in robotic protection design, although it is of less interest in prior research, water cooling method proves to be effective and economical through our high temperature experiment. This paper also presents an energetic analysis method to probe into the global process of water cooling and to evaluate the cooling system.

Considering that the photocatalysts used in research are generally in powder form, which increase the difficulty of efficient recycle in practice, this research focused on the generation of graphene-titanium dioxide nanotubes catalytic board. Graphene oxide and TiO

A luminescent cadmium(II) metal-organic framework, [Cd(tppa)2 (bpdc)2]n (1) (tppa = tri(4-pyridylphenyl)amine, bpdc =4,4′-biphenyldicarboxylic acid), has been solvothermally synthesized by using Cd(NO3)2·4H2O and a mixture of tppa and bpdc. Single crystal X-ray analysis reveals that 1 crystallizes in the orthorhombic system and Pbcn space group. Its overall structure is a twofold interpenetrated framework, and it shows a porosity of 31.8% based on a calculation by PLATON and a 4-c type topological network with the point symbol of {6^5.8}. In addition, 1 may be exploited as WLED due to its ability to give off yellow light under ultraviolet excitation.

Since China has successfully built her first Experimental Advanced Superconducting TOKAMAK (EAST) several years ago, great interest and demand have been increasing in robotic in-vessel inspection/operation systems, by which an observation of in-vessel physical phenomenon, collection of visual information, 3D mapping and localization, even maintenance are to be possible. However, it has been raising many challenges to implement a practical and robust robotic system, due to a lot of complex constraints and expectations, e.g., high remanent working temperature (100 °C) and vacuum (10−3 pa) environment even in the rest interval between plasma discharge experiments, close-up and precise inspection, operation efficiency, besides a general kinematic requirement of D shape irregular vessel. In this paper we propose an upgraded robotic system with redundant degrees of freedom (DOF) manipulator combined with a binocular vision system at the tip and a virtual reality system. A comprehensive comparison and discussion are given on the necessity and main function of the binocular vision system, path planning for inspection, fast localization, inspection efficiency and success rate in time, optimization of kinematic configuration, and the possibility of underactuated mechanism. A detailed design, implementation, and experiments of the binocular vision system together with the recent development progress of the whole robotic system are reported in the later part of the paper, while, future work and expectation are described in the end.

A series of xanthene derivatives were prepared from cyclohexane-1,3-dione and aromatic aldehydes through Knoevenagel–Michael and cyclisation reactions in methanol:ethanol mixture (1:1), catalysed by a very small amount of l-proline at room temperature. Isomeric tetraketones were synthesised from dimedone and aromatic aldehydes under the same condition. Condensation of them with amines gave acridione derivatives. The crystal structure of an acridione was obtained and determined by X-ray single-crystal diffraction.

A series of novel 10-substituted 3,6-diphenyl-9-aryl-3,4,6,7,9,10-hexahydroacridine-1,8(2H,5H)-dione derivatives synthesised by condensation of different amines with xanthenes, was prepared from 5-phenylcyclohexane-1,3-dione and aromatic aldehydes by a Knoevenagel and Michael reaction and cyclisation catalysed by a trace of l-proline at room temperature. In addition, the molecular structure of a xanthene was determined by single-crystal X-ray diffraction analysis.

The objective of this study was to characterize the photodegradation ability of pentachlorophenol (PCP) in β-cyclodextrin (β-CD) soil washing solution. After contaminated soil remediation by β-CD soil washing method, solution contained target contaminant was further treated with photodegradation technique. Degradation processes with Xe lamp to simulate natural sun light was investigated under different temperature, and various aeration rate. TiO2employed as photocatalyst was also tested in the soil washing system. The result demonstrated that photodegradation rate of PCP in soil washing solution was related to the aeration rate. The reaction could be slightly accelerated by increasing the temperature. TiO2adding will decrease the degradation speed, while using it together with H2O2will extremely increase the degradation rate of the target contaminant in this condition.

A pilot-scale combined system composed of anaerobic digenstion, membrane bioreactor (MBR) and Electro-Catalyzed oxidation processes has been set up to treat the leachate from municipal solid waste (MSW) transfer station. System performance was evaluated by ammonia and chemical oxidation demand (COD) removal . Results showed that 97% of ammonia was removed by MBR, and the elimination of COD was mainly completed in anaerobic process and MBR with a total removal of 99%. In addition, the analysis of microbial communities in the MBR, carried out by clone library and denaturing gradient gel electrophoresis (DGGE) of the 16S rRNA genes, indicated a highly diverse bacterial community and the enrichment of N-cycling bacteria.

Two luminescent metal–organic-frameworks (LMOFs) constructed by a molecular chromophore [tri(4-pyridylphenyl)amine] (tppa) were synthesized by solvothermal reactions and characterized by single crystal and powder X-ray diffraction, thermogravimetric analysis, optical diffuse reflection, photoluminescence spectroscopy, and internal quantum yield measurements. Both compound 1 [Zn(tppa)(ndc)·(DMF)4] and compound 2 [Zn4(tppa)2(sdc)3(NO3)2·(DMF)4·(ACN)2] (ndc = 2,6-naphthalenedicarboxylic acid, sdc = (E)-4,4′-(ethene-1,2-diyl)dibenzoic acid, DMF = dimethylformamide, ACN = acetonitrile) exhibit intense yellow emission under blue light (455 nm) excitation. The Commission International de I'Eclairage (CIE) coordinates of 1 (0.42, 0.53) and 2 (0.42, 0.54) are close to that of YAG:Ce3+ (0.41, 0.55) (λex = 455 nm). The two phosphor materials show promise for use in phosphor-converted white LEDs (PC-WLEDs).

A series of novel 10-substituted 3,6-diphenyl-9-aryl-3,4,6,7,9,10-hexahydroacridine-1,8(2H,5H)-dione derivatives synthesised by condensation of different amines with xanthenes, was prepared from 5-...

The central di­hydro­pyran ring of the compound shows an envelope conformation. In the crystal, O—H⋯O hydrogen bonds link the mol­ecules into supra­molecular chains propagating along the a-axis direction., In the octa­hydroxanthenedione unit of the title compound, C31H27NO6, the central di­hydro­pyran ring shows an envelope conformation, while the bilateral cyclo­hexene and cyclo­hexane rings adopt a half-boat conformation and a chair conformation, respectively. The nitro­benzene ring is twisted with respect to the two benzene rings, making dihedral angles of 63.1 (1) and 63.0 (1)°. In the crystal, O—H⋯O hydrogen bonds link the mol­ecules into supra­molecular chains propagating along the a-axis direction.

The Excitation-emission matrix (EEM) fluorescence spectra of dissolved organic matter (DOM) are not only dependent on the chemical structure of DOM as well as the local chemical environment around the DOM, but also dependent on the instrument employed for the analysis. Thus, in order to get the real spectra of the DOM, spectra correction of the effect of the instrument-specific response is necessary. However, some studies corrected DOM spectra, while still some studies didn't, leading to inconformity when comparing the data and the results from different groups. The present work evaluated the effect of spectra correction on the fluorescence characteristics of DOM. The results demonstrated that DOM spectra differed significantly after correction. Fluorescence intensities showed a decrease in the range of Ex/Em = 220-450/250-500 nm, while an increase at Em250 nm after correction. Fluorescence intensity ratio (FI) and humification index (HIX) derived from peak picking method showed a decrease after correction, while biological index (BIX) increased slightly. P(I), n, P(II), n and P(III), n derived from FRI analysis exhibited a significant increase, while P(IV), n and P(V), n decreased. The results suggest that spectral correction should be included when analyzing the properties and trends of the DOM using EEM.