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Lead is the main toxic factor in jarosite residue. It is important to study the release behavior of lead from simulated lead-bearing jarosite (SLBJ) for predicting the stability of jarosite residue and its secondary pollution to the environment. To identify the technical issues and limitations associated with its safe disposal, a comprehensive analysis of the chemical, structural, and morphological characteristics of SLBJ was conducted using various detection techniques including XRF, XRD, SEM-EDS, FTIR, XPS, etc. The environmental stability of SLBJ was assessed through the toxicity characteristic leaching procedure (TCLP), Chinese standard leaching tests (CSLT), and a long-term leaching experiment (LTLE). Phase composition analysis revealed that the primary components of SLBJ are sodium jarosite and lead sulfate. TCLP and CSLT results indicated that lead content surpassed the toxicity identification standard limit by more than 47 times. Furthermore, LTLE indicated that the lead concentration surpassed the standard limit about 15 times after prolonged contact time. This study is of great significance for predicting the stability of jarosite residue and its secondary pollution to the environment. [ABSTRACT FROM AUTHOR]

The in situ hydrolysis of acetontrile to acetate was utilized to construct crystal structures of lanthanide complexes for two analogous ligands, including dimeric [Ln2(Hhpip)2(OAc)6] (Ln = Eu, Tb, Dy; Hhpip = 2-(2-hydroxyphenyl)imidazo[4,5-f][1,10]phenanthroline) and two-dimensional polymeric [Tb(hnpip)(OAc)2]n, where hnpip− is the hydroxyl-deprotonated form of 2-(2-hydroxy-5-nitrophenyl)imidazo[4,5-f][1,10]phenanthroline acting as a tridentate bridging ligand. The former had a [Ln2(μ-η1:η2-OAc)2(μ-η1:η1-OAc)2(η2-OAc)2] subunit, whereas in the latter, [Tb2(μ-η1:η2-OAc)2] and [Tb2(μ-η1:η1-OAc)2] subunits are alternately aligned. The DMSO solution of [Eu2(Hhpip)2(OAc)6] and [Eu2(pip)2(OAc)6] (pip is 2-phenylimidazo[4,5-f][1,10]phenanthroline) were found to have a specific and prompt photoluminescence response to CO32− with significant emission colour change. The limit of detection was about 10 μM, depending on the complex and wavelength monitored. [ABSTRACT FROM AUTHOR]

Crystalline sponge method represents a rather new trend in structural analysis. This method is to use networked porous metal complexes as “crystalline sponges”, which does not require the crystallization of the sample. It has large and regular cavities which can absorb the target molecules like sponges and arrange them in an orderly manner, so that their structures can be determined with X-ray diffraction. In this review, we focus on recent trends in crystalline sponge method. Following an introduction in the field, a first main section covers the birth of crystalline sponge method and the improvement of crystal synthesis method. The further section covers structural confirmation, including the guest molecular structure determination and host-guest interactions. The next main section covers the expansion of crystalline sponge method, such as the applications in synthesis, other crystalline sponge and visual observation. The final section covers the limitations and prospects of the crystalline sponge method. [ABSTRACT FROM AUTHOR]

For solution-based small-molecule organic photovoltaic cells (SM BHJ), thermal annealing is often regarded as a very vital processing to yield high-efficiency devices. Here, the device with the photoactive p-DTS(FBTTh2)2:PC60BM blends has been studied by varying the annealing temperature. The highest power conversion efficiency (PCE), fill factor (FF), and short-circuit current ( Jsc) has been achieved after the device was annealed at the temperature of 80 °C. X-ray diffraction (XRD) displayed that the p-DTS(FBTTh2)2 tends to form big islands with well-defined crystalline structure (long coherence length) surrounded by small islands of the PC60BM after annealing, and reached the largest grain size of 27 nm after annealing at 80 °C. AFM images demonstrated the most sufficient phase separation within the photoactive blend layer after annealing at 80 °C, which provides good photogenerated excitons dissociation. Such improvements have proved beneficial to decrease the ohmic loss and recombination in carrier-transport process via measuring series resistance and shunt resistance as well as hole mobility. This work opens up a new way to understand the relationship between thermal annealing and molecular interaction from the viewpoint of lattice relaxation. [ABSTRACT FROM AUTHOR]

A series of lanthanide-doped polyoxometalate microtubes, Ln-SiW 12 (Ln=Nd, Dy and Yb), have been synthesized, and characterized by X-ray diffraction, elemental analysis and thermogravimetric analysis. In the microtubes, the lanthanide cations combine with polyanions through electrostatic interaction. Furthermore, the lanthanide-doped microtubes were chelated with 8-hydroxyquinoline (HQ) in a post-synthesis step (designed as LnQ-SiW 12 ). The LnQ-SiW 12 show characteristic near-infrared (NIR) luminescence, corresponding to Ln 3+ ions due to efficient energy transfer from Q to the Ln 3+ ions through antenna effect. [ABSTRACT FROM AUTHOR]

Abstract: Ni/xPr-Al2O3 (x = 5, 10, 15, 20 wt%) catalysts with an application in autothermal reforming of methane were prepared by sequential impregnation synthesis; its catalytic performance was evaluated and compared with that of Ni/γ-Al2O3 catalyst; the physicochemical properties of the catalysts were characterized by X-ray diffraction (XRD), Transmission electron microscope (TEM), X-Ray Photoelectron Spectrometer (XPS), Thermo Gravimetric Analyzer (TGA) and H2-temperature programmed reduction techniques (TPR). The results showed that Pr addition promoted the reduction of nickel particle size on the surface. TPR experiments suggested a heterogeneous distribution of nickel oxide particles over xPr-Al2O3 supports and the promotion of NiO reduction by Pr modification. The CH4 conversion increased with elevating levels of Pr addition from 5% to 10%, then decreased with Pr content from 10% to 20%. For the stability catalytic tests, Ni/xPr-Al2O3 catalysts maintained the high activity after 48 h while Ni/Al2O3 had a significant deactivation. [Copyright &y& Elsevier]

The rational self-assembly of mono-lacunary Keggin clusters with 4d and 4f metal salts via a conventional method has yielded two novel polyoxometalate-based 4d–4f heterometallic compounds containing lacunary Keggin anions connected to ten metal atoms: {[Ag{Ag2(H2O)4}{Ln(H2O)6}2H ⊂ {SiW11Ln(H2O)4O39}2]·nH2O (Ln = Ce and n = 7 for 1, Ln = Pr and n = 3 for 2). Their structures were determined by single crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, and thermogravimetric (TG) analyses. A structural feature in 1 and 2 is that each [SiW11O39]8− cluster (SiW11) is connected to ten metals (five Ag+ and five Ln3+ cations), representing the highest number of connected metal atoms to any mono-lacunary Keggin anion to date. This large connectivity leads to a structure with a purely inorganic 3D framework with two kinds of channels along the [100] and [010] directions. The magnetic properties of both compounds show the expected magnetic moments (0.8 and 1.6 amu K mol−1 per Ce3+ and Pr3+ ion, respectively) and confirm the presence of isolated Ce3+ and Pr3+ ions. [ABSTRACT FROM AUTHOR]

Two bisupporting Keggin-type polyoxoanion-based hybrids decorated by [Zn(phen) 2] 2+ complexes, [Zn(phen) 2] 2(PW 11VIW VO 40) ( 1) and K[Zn(phen) 2(H 2O)] 2(OH) (SiW 12O 40) ·H 2O ( 2) (phen = 1,10′-phenanthroline), have been hydrothermally synthesized, and characterized by elemental analysis, IR spectra, UV–Vis spectrum, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis, and single-crystal X-ray diffraction. The structural analyses reveal that compound 1 consists of a 0D bisupporting Keggin-type heteropoly blue cluster obtained by using reductant glucose, which is grafted by two [Zn(phen) 2] 2+ fragments; compound 2 presents a 1D infinite chain, which is constructed from bisupporting [SiW 12O 40] 4− polyoxoanions decorated by [Zn(phen) 2(H 2O)] 2+ fragments and K + ions. Additionally, the electrochemical behaviors of two compounds were studied. [ABSTRACT FROM AUTHOR]

Abstract: Two new Dawson-based hybrids, namely, [Ag6(H L)4(H2O)6(P2W18O62)]·4H2O (1) and [Ag4(H2biim)4][K2(H2O)3(P2W18O62)]·H2O (2) (HL=5-(4-imidazol-1-yl-phenyl)-2H-tetrazole, H2biim=2,2′-biimidazole), have been hydrothermally synthesized and characterized. X-ray diffraction analysis reveals that compound 1 is a 3D structure based on infinite organic–metal chains {Ag6(HL)4}n and Wells–Dawson anions. Compound 2 displays a 3D framework based on potassium-Dawson inorganic sheets and dinuclear silver-H2biim units. The luminescent properties of compounds 1 and 2 have also been investigated. [Copyright &y& Elsevier]

Zr0.9Mg0.1O2-δ nanofibers and ZrO2 nanofibers are synthesized using electrospinning and the calcination technique. The nanofibers are characterized using x-ray diffraction (XRD), a field emission scanning electron microscope (FE-SEM), and a Brunauer-Emmett-Teller (BET) surface analyzer. The humidity sensing properties of Zr0.9Mg0.1O2-δ nanofiber sensors are analyzed and compared with those of ZrO2 nanofiber sensors. The Zr0.9Mg0.1O2-δ nanofiber humidity sensors exhibit a broader humidity range of 11-97% relative humidity (RH), good linearity, small humidity hysteresis, and rapid response and recovery times. The complex impedance plots of the Zr0.9Mg0.1O2-δ sensor at different RHs are drawn, and the humidity sensing mechanism is discussed via an equivalent circuit. [ABSTRACT FROM AUTHOR]

Three inorganic-organic hybrid complexes, [Cu(Hbiim)(OH)](SiWO)·2HO ( 1), [Cu(Hbiim)](SiWO)·2HO ( 2) and [Ag(Hbiim)](SiWO)·2HO ( 3) (Hbiim = 2, 2′-biimidazole), have been synthesized under hydrothermal conditions, and characterized by elemental analysis, IR, PXRD, TG and single-crystal X-ray diffraction. The crystallographic analysis reveals that in compounds 1- 3, the Keggin polyanions [ α-SiWO] act as inorganic building blocks, which are linked with the dinuclear metal-organic units via Cu-O bonds in compound 1, or through supramolecular interactions in compounds 2 and 3. Compound 1 shows a 3D supramolecular structure constructed by net-like layers. Compounds 2 and 3 display 2D layer structures which were composed of wave-like chains. In addition, these compounds show electrochemical activities, and photoluminescence properties are measured in the solid state. [ABSTRACT FROM AUTHOR]

Abstract: La0.7Sr0.3FeO3 nanoparticles assembled nanowires were synthesized by a hydrothermal method assisted with cetyltrimethylammonium bromide (CTAB). The hydrothermal temperature was 180°C and the annealed temperature was 700°C. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to characterize the morphology, composition and structural properties of the materials. The results showed that the La0.7Sr0.3FeO3 nanoparticles assembled nanowires had a high aspect ratio (the largest aspect ratio >100); the size of the nanoparticles was about 20nm and the diameter of the nanowires was about 100–150nm. The growth mechanism of La0.7Sr0.3FeO3 nanowires was discussed. Gas sensors were fabricated by using La0.7Sr0.3FeO3 nanowires. Formaldehyde gas sensing properties were carried out in the concentration range of 0.1–100ppm at the optimum operating temperature of 280°C. The response and recovery times to 20ppm formaldehyde of the sensor were 110s and 50s, respectively. The gas sensing mechanism of La0.7Sr0.3FeO3 nanowires was investigated. [Copyright &y& Elsevier]

Abstract: Two isostructural Keggin-templated compounds containing a chair-like heptanuclear silver complex, [{Ag7(Hbtz)2(btz)4}{PM12O40}]·H2O (M=W, 1; Mo, 2) (Hbtz=benzotriazolate), have been hydrothermally synthesized and characterized by routine methods and single crystal X-ray diffraction. In the compounds 1 and 2, the Hbtz ligands present two types of coordination modes. A pentameric silver chain with two kinds of Ag⋯Ag weak interactions exists in the heptanuclear silver complex. The heptanuclear silver cations connect the polyoxoanions PM12O40 3− to a two-dimensional layer, and the adjacent layers are fused together by the pseudo wave-like chains, H-bonds and AgI–π interactions, constructing a three-dimensional net. Furthermore, electrochemical properties have been studied for compounds 1 and 2 and the two compounds display excellent electrocatalytic activities to the reduction of nitrite. [Copyright &y& Elsevier]

Abstract: The role of CaO in the extraction of Ni and Mo from carbonaceous shale by calcification roasting, sulphation roasting and water leaching was studied. Experimental results showed that 97.23% Mo and 93.16% Ni were extracted from the Ni–Mo ore by mixing 100g the raw Ni–Mo ore with 36g CaO and grinding to less than 106μm, then oxidation roasting at 700°C for 2h, sulphation roasting with 70ml 98% sulphuric acid at 240°C for 2h and, water leaching at 98°C for 2h with a liquid/solid ratio of 2:1. But only 60.67% Ni was extracted for the oxidation roasting without adding CaO. The addition of CaO in the ore is both propitious to environment protection and nickel extraction. XRD analysis showed that the nickel in the calcification roasted ore was in the form of NiO, while the nickel in the oxidation roasted ore was in the form of NiFeO4. It was found that the NiFeO4 formed in the oxidation roasted Ni–Mo ore was included by chemically inert iron silicates, which results in the NiFeO4 irresolvable in sulphuric acid. Experiments confirmed that CaO can decompose not only the NiFe2O4 but also the iron silicates at the roasting temperature. [Copyright &y& Elsevier]

By introducing different polyoxotungstates into the Ag–H2biim system, four new compounds with distinct architectures, Ag2(H2biim)4(W6O19)·2H2O (1), Ag6(H2biim)6(SiW12O40)(OH)2·2H2O (2), Ag6(H2biim)6(PW12O40)(OH)3·H2O (3) and Ag6(H2biim)6(P2W18O62)·12H2O (4) (H2biim = 2,2′-biimidazole), have been hydrothermally synthesized, and characterized by routine physical methods and single crystal X-ray diffraction. In compound 1, the Lindqvist type polyoxotungstate {W6} combines with the chelate Ag–H2biim complex forming a discrete “dumbbell-like” motif. Isostructural compounds 2and 3are obtained by introducing Keggin polyoxotungstates ({SiW12} and {PW12}, respectively), which show a 2D layer structure. The 2D layers parallel each other to form a 3D supramolecular framework. The larger Wells–Dawson polyoxotungstate {P2W18} directs the formation of compound 4, in which one 2D layer is the inversion of the neighboring ones. Furthermore, there exist infinite Ag chains in compounds 2–4, which are quite unusual in POM-based compounds. The distinction among the final four architectures is ascribed to the structure-directing effect of different polyanions. The electrochemical properties of compounds 1–4are studied. In addition, the antibacterial properties of the four compounds against negative Escherichia coli (E. coli) and positive Staphylococcus aureusare investigated. [ABSTRACT FROM AUTHOR]

Abstract: Three compounds, [Na(bie)]2H[PW12O40] (1), [Cu(bie)]4[SiW12O40] (2) and [Cu(bie)]3H2[H3W12O40] (3) (bie=2,2′-bis(1H-imidazolyl)ether) have been hydrothermally synthesized by introducing different metal cations and polyanions, and characterized by routine physical methods. Their crystal structures have been established by single crystal X-ray diffraction. Compound 1 shows a 1D infinite chain which is composed of Na-bie coordination polymers and PW12 polyanions. By using the CuI cation, compounds 2 and 3 which show the 2D layer architectures were obtained. Due to the different polyanions of compounds 2 and 3, the topologies of the 2D layers are distinct. Further, the electrochemical properties of compounds 1–3 were studied. [ABSTRACT FROM AUTHOR]

Abstract: A new compound, [Cu4(bix)3V4O12] (1) (bix=1,4-Bis(imidazol-1-ylmethyl)benzene), has been hydrothermally synthesized, and characterized by elemental analyses, IR spectroscopy, thermogravimetric analysis, and single X-ray diffraction. In the structure of compound 1, the 2D layer is constructed from the ladder-like chains in which the [V4O12]4− polyanions act as the middle rails. The whole structure exhibits an interdigitated architecture which is unusual in the polyoxometalate family. Further, the electrochemistry property of the compound is studied. [ABSTRACT FROM AUTHOR]

Two new compounds based on Anderson-type polyanions, H(C6H9N3O2)2[Mn(H2O)2][Al(OH)6Mo6O18] ⋅ 6H2O (1) and (C6H10N3O2)2[Ag(H2O)2][Cr(OH)6Mo6O18] ⋅ 6H2O (2), have been synthesized in aqueous solution and characterized by elemental analyses, IR, TG, and single crystal X-ray diffraction. Both compounds show inorganic 1-D chain-like structures in which the Anderson-type polyanions are bidentate ligands chelating to two metal cations. Further, transition metal cations are in the same line with the center Al (Cr), which is unusual in 1-D inorganic chains based on Anderson-type polyanions. Free histidine molecules further link the chains into 3-D supramolecular frameworks via hydrogen interactions. Electrochemical and fluorescence quenching properties were investigated. [ABSTRACT FROM AUTHOR]

Abstract: Two couples of new compounds templated by the polyanion [SiW12O40]4−,[Hbix][CuI(bix)]3[SiW12O40]·4H2O (1) and [CuII(H2O)(Hbix)2(bix)]2[CuII(H2O)2(Hbix)2(bix)][SiW12O40]3·4H2O (2) (bix = 1,4-Bis(imidazol-1-ylmethyl)benzene), [CuI(bbi)]4[SiW12O40]·2H2O (3) and [CuII(bbi2)]2[SiW12O40] (4) (bbi = 1,1′-(1,4-butanediyl)bis(imidazole)) were hydrothermally synthesized, and characterized by elemental analyses, IR spectroscopy, thermogravimetric analyses and single X-ray diffraction. Compounds 1 and 2 were synthesized from the same reactants but exhibited distinct structures which could be ascribed to the different ratios of the reactant bix to CuII. In compound 1, the higher ratio of bix results in the transformation of the CuII to CuI, the [SiW12O40]4− templates direct the CuI–bix coordination polymers to form a 3D supramolecular framework with grid-like channels along two directions. The [SiW12O40]4− templates in compound 2 locate in the voids of the 3D supramolecular network constructed by CuII–bix coordination polymers, which exhibits the interdigitation fashion in both the formation of the 2D layer and the 3D framework. Compounds 3 and 4 were synthesized similar to 1 and 2, except for the change of bix to bbi. In compound 3, the CuI–bbi polymers form a supramolecular metal–organic host framework with rhombic channels in which the SiW12 templates reside. Compound 4 shows a framework with hexagonal channels constructed by CuII–bbi coordination polymers which accommodated the SiW12 templates. [Copyright &y& Elsevier]

In this paper, single-phase nanocrystalline La1-xSrxFeO3 (x = 0.1, 0.2, 0.3, 0.4 and 0.5) with perovskite structure were prepared by employing sol-gel method. XRD and TEM were used to characterize the materials. Dielectric properties of La1-xSrxFeO3 (x = 0.1, 0.2, 0.3, 0.4 and 0.5) were investigated. The experiments were carried out as a function of Sr doping (0.1 ≤ x ≤ 0.5) and frequency (10-105 Hz) in different relative humidity (RH) at 25°C. The results revealed that capacitance decreased as the frequency increased, and the peaks of dielectric loss appeared at high relative humidity range. Humidity sensing properties were also studied in this work. It was found that La0.7Sr0.3FeO3 exhibited high humidity sensitivity and small hysteresis from 33% RH to 98% RH. [ABSTRACT FROM AUTHOR]

Abstract: Three new compounds, [Cu(C6H8N3O2)(C6H9N3O2)(H2O)2][Na(H2O)2]2[Al(OH)6Mo6O18]·6H2O (1), [Cu(C6H8N3O2)(C6H9N3O2)(H2O)2][Na(H2O)]2[Cr(OH)6Mo6O18]·3H2O (2) and [Cu(C6H10N3O2)(C6H9N3O2)(H2O)2][Al(OH)6Mo6O18]·9H2O (3) have been synthesized and characterized by elemental analyses, IR, TG, and single crystal X-ray diffraction. In the structures of compounds 1 and 2, the sodium cations connected the Anderson-type polyoxoanions to form 1D zigzag chains, which are connected to 2D layers by the Cu-histidine complexes. Compound 3 is a contrast for them, when the reactant without sodium cations is used, a discrete structure is formed. [Copyright &y& Elsevier]

Abstract: Two new compounds based on Weakley-sandwich-type polyanion (WSP), H2[Mn(en)2]2[Mn(en)2(H2O)]2[Mn4(H2O)2(PW9O34)2]·9H2O (1) and Na2[Co(en)2]2[{Co(en)2(H2O)]2[Co4(H2O)2(PW9O34)2]·9H2O (2) (en=ethylenediamine), have been synthesized by the hydrothermal reaction of the trivacant Keggin polyoxoanion [a-A-PW9O34]9− with transition metal ions and en, and structurally characterized by routine physical methods and single-crystal X-ray diffraction. Compound 1 represents a 1D chain structure made up of WSPs and [Mn(en)2]2+ ions. Compound 2 represents a 2D layer structure formed by the interconnection of WSPs, [Co(en)2]2+ and Na+ ions. Compounds 1 and 2 represent the first example of high-dimensional construction based on WSPs and transition metal complexes (TMCs), in which the water molecules located on the featured tetra-metal unit are still remained, and exhibit the property of sorption/desorption of water molecules. [Copyright &y& Elsevier]

Abstract: A new hybrid constructed from Wells–Dawson polyanions and silver complexes, [Ag(bipy)]2[Ag(bipy)(Hbipy)][P2W18O62]·[H2bipy] (1) (bipy=4,4′-bipyridine), has been hydrothermally synthesized, and characterized by IR, TG, XRPD and single-crystal X-ray diffraction. Structural analysis reveals that compound 1 possesses left- and right-helical chains constructed by Ag(bipy) complexes. Furthermore, these helical chains are linked together by Ag atoms via sharing O atoms of the Wells–Dawson polyanions to form two-dimensional (2D) sheets. Finally, a 3D framework is obtained with (41·64·81)(46·62·82·105) topology, which is constructed by the 2D sheets through the O atoms of the Wells–Dawson polyanions. Also, the electrochemical behavior and electrocatalysis of 1 modified carbon paste electrode (1-CPE) have been studied in detail. The results indicate that 1-CPE has remarkable stability and good electrocatalytic activities. [Copyright &y& Elsevier]

Abstract: An inorganic–organic hybrid complex, {[Cu2(phen)2(OH)2(H2O)]2[α-SiW12O40]}·8H2O 1, (phen=1,10-phenanthroline), has been synthesized under mild reaction conditions and characterized by single-crystal X-ray diffraction, IR spectrum, thermal analyses (TG-DTA) and fluorescent measurement. The crystallographic analysis reveals that in the compound, the Keggin polyanion [α-SiW12O40]4− acts as the inorganic building block, two [Cu2(phen)2(OH)2(H2O)] units covalently bond to it via terminal oxygen atoms of the Keggin anion. An open framework is formed through supramolecular interactions with solvent accessible volume of 18% in the unit-cell. Dehydration and re-adsorption of water in 1 were investigated by X-ray powder diffraction (XRPD).The compound shows thermal stability and photoluminescence property in the solid state. [Copyright &y& Elsevier]

Abstract: A novel one-dimensional Wells–Dawson-based compound H2(bbi)0.5[Ni(phen)(bbi)2]2[P2W18O62] (phen=1,10′-phenanthroline, bbi=1,1′-(1,4-butanediyl)bis(imidazole)), has been prepared under the hydrothermal conditions and structurally characterized by elemental analysis, cyclic voltammetry, IR and XPS spectra and single-crystal X-ray diffraction. The title compound exhibits an interesting wavelike chain constructed from Dawson type polyoxoanion and mixed rigid and flexible ligands decorated [Ni(phen)(bbi)2]2+ cationic complex. It represents the first example of polyoxometalate that built from the rigid and flexible ligands at the same time. [Copyright &y& Elsevier]

In this article, we report the syntheses and structures of two new inorganic–organic hybrid copper molybdates with organonitrogen ligands, [Cu2(bpe)(Mo2O8)] · 3H2O (1) (bpe = 1,2-bis(4-pyridyl)ethene) and [{Cu(4,4′-bpy)}2(Mo2O8)] (2) (bpy = 4,4′-bipyridine). Elemental analyses, IR spectra, EPR spectra, XPS spectra, TG analyses and single crystal X-ray diffraction were used to characterize these compounds. The structure of 1 exhibits a pillared-layer framework built up from unusual bimetallic two-dimensional sheets pillared by linear bpe ligands. Compound 2 features a pillared-layer structure constructed from copper molybdate 4,8-net sheets connected by 4,4′-bpy ligands. [ABSTRACT FROM AUTHOR]

Abstract: The present study attempts to use hydrogen peroxide solution to humidify Ca(OH)2 particles to enhance the absorption of SO2 to achieve higher removal efficiency and to solve the valuable reuse of the reaction product in the semidry flue gas desulfurization (FGD) process. Experiments were carried out to examine the effect of various operating parameters including hydrogen peroxide solution concentration, Ca/S molar ratio and approach to adiabatic saturation temperature on SO2 removal efficiency in a laboratory scale spray reactor. The product samples were analyzed to obtain semi-quantitative measures of mineralogical composition by X-ray diffraction (XRD) with reference intensity ratio (RIR) method and the morphology of the samples was examined by scanning electron microscope (SEM). Compared with spraying water to humidify Ca(OH)2, SO2 removal efficiency was improved significantly by spraying hydrogen peroxide solution of 1–3wt.% to humidify Ca(OH)2 because hydrogen peroxide solution enhanced the dissolution and absorption rate of SO2. Moreover, XRD and SEM analyses show that the desulfurization products contain less amount of unreacted Ca(OH)2 and more amount of stable calcium sulfate with increasing hydrogen peroxide solution concentration. Thus, the process mechanism of the enhanced absorption of SO2 by spraying hydrogen peroxide solution to humidify Ca(OH)2 was elucidated on the basis of the experimental results. [Copyright &y& Elsevier]

Abstract: A new compound, {[Cu2(DF)2H2O]2SiMo12O40} (1) (DF=4,5-diazafluoren-9-one), has been hydrothermally synthesized and characterized by routine methods and single crystal X-ray diffraction. In 1, all the DF only adopt the unusual bidentate coordination mode for the first time coordinating to Cu atoms to form copper-dimers which link [SiMo12O40]4− clusters obtaining an intertwined double chain. Furthermore, the luminescent and electrochemical properties of the title compound have been studied. [Copyright &y& Elsevier]

Abstract: A Ag-bridged V-centred tungstovanadate dimer capped by [Ag(phen)] unit, [Ag(phen)2]7{Ag[Ag(phen)(VW10V2O40)]2} (1) (phen=1,10-phenanthroline), has been hydrothermally synthesized, and characterized by IR, TG and single-crystal X-ray diffraction. Structural analysis reveals that the compound is composed of one dimeric {Ag[Ag(phen)(VW10V2O40)]2}7− anion and seven [Ag(phen)2]+ cations, which represents the first V-centred tungstovanadate grafted by transition metal coordination polymers. Furthermore, the electrochemical properties of 1 have been studied in the paper. [Copyright &y& Elsevier]

Abstract: Two novel polyoxometalate(POM)-templated coordination polymers: [Cu2(phnz)3][M6O19] (M=Mo for 1, W for 2; phnz=phenazine), have been hydrothermally synthesized and characterized by routine physical methods and single crystal X-ray diffraction. In the compounds, Lindqvist POMs as templates induce the [Cu2(phnz)3] complexes to 2D hexagonal metal-organic framework (MOF), which represents 63 topologies of dimensions ca. 13.515×13.515×13.515Å. Furthermore, the 2D sheets are held together by Lindqvist POMs into 3D supramolecular networks with 1D channel, and Lindqvist POMs site in the channels. The successful syntheses and isolation of two compounds provide a novel example of the utility of POM clusters as templates for self-assembly extended framework with cavities. [Copyright &y& Elsevier]

Abstract: Two new supramolecular assemblies based on Keggin-type polyoxometalates, [Ag3(4,4′-bipy)2(2,2′-bipy)2][Ag(2,2′-bipy)2][{Ag(2,2′-bipy)}HSiW11VO40] (1) and [Ag3(4,4′-bipy)2(2,2′-bipy)2][Ag(2,2′-bipy)2][{Ag(2,2′-bipy)}PW11VO40] (2) (4,4′-bipy=4,4′-bipyridine, 2,2′-bipy=2,2′-bipyridine), have been synthesized under the hydrothermal conditions and structurally characterized by IR, XPS, TG and single-crystal X-ray diffraction. Compound 1 has a 2D layer network structure via weak Ag...O interactions. Compound 2 is isostructural with compound 1. In addition, the fluorescence of compound 1 is reported. [Copyright &y& Elsevier]

Abstract: Two novel organic–inorganic hybrid polyoxometalates, (X=P, m =1 1; X=Si, m =2 2; 2,2′-bpy=2,2′-bpyridine), have been synthesized under hydrothermal conditions and structurally characterized by single-crystal X-ray diffraction. They are isostructural, possessing orthorhombic, and the parameters of unit cells for compound 1 are space group Pbca, a =17.317(4)Å, b =17.092(3)Å, c =20.587(4)Å, V =6445(2)Å3, Z =4; for compound 2 are space group Pcab, a =17.181(3)Å, b =18.198(4)Å, c =20.672(4)Å, V =6463(2)Å3, Z =4. The two compounds show a layer framework constructed from Keggin-polyoxoanion clusters and [Cu (2, 2′-bpy)2]2+ coordination polymer fragments via weak covalent interactions, resulting in a 3D network via supramolecular interactions. Their electrochemical properties are studied in detail. [Copyright &y& Elsevier]

Abstract: Two new hexadecavanadate derivatives, (bpy)[Zn(4,4′-bpy)2]2[H4ClV16O38]·6H2O 1 and (bpy)[Co(4,4′-bpy)2]2[H4ClV16O38]·6H2O 2 (bpy=4,4′-bipyridine), were synthesized under the hydrothermal conditions and structurally characterized by IR, XPS and EPR spectroscopy, redox titration and single-crystal X-ray diffraction. The two compounds are isostructural and crystallize in the tetragonal non-centrosymmetric space group P-4n2 (No. 118) with a =17.124(2), b =17.124(2), c =14.724(3)Å, V =4317.5(12)Å3 and Z =1 for the compound 1, and a =17.038(2), b =17.038(2), c =14.754(3)Å, V =4282.9(12)Å3 and Z =1 for the compound 2. Compounds 1 and 2 were constructed from 4-connected {H4ClV16O38} clusters and 6-connected Zn(II) or Co(II) ions, extending in the three dimensions. Square channels with an opening of ca. 7.2×7.2Å were formed through the twining double left-handed helical chains composed of MII octahedral complexes bridged by bpy molecules, which were filled by water and free bpy molecules. Magnetic property was also studied. [Copyright &y& Elsevier]

The first example of one-dimensional organic–inorganic polymetallic coordination polymer based on heptamolybdate anions, formulated (NH4)[Cu(en)2][Na(en)Cu(en)2(H2O)(Mo7O24)] · 4H2O (en = ethylenediamine) (1) has been hydrothermally synthesized and characterized by element analysis, IR, EPR, CV and single crystal X-ray diffraction. The structure of 1 is fabricated by self-assembly of integrated heptamolybdic anions without collapse of primary structure and copper-ethylenediamine(en) coordination groups into one-dimensional zigzag-shaped chains. [Copyright &y& Elsevier]

The ‘saline mudstone’ sequence of the Paleogene Shahejie Formation in the Dongpu Depression of Bohai Bay Basin is a major source rock for conventional hydrocarbons. However, shale oil, having a density of ~ 0.9 g/cm 3 and a viscosity of ~ 21 mPa·s, has also been discovered and is being produced from these mudstones. To better understand the occurrence of such shale oil, geochemical petrological and mineralogical investigations were carried out on a suite of saline mudstone samples by using Rock-Eval, X-ray diffraction and SEM. The Shahejie Formation samples analyzed in the current study are characterized by type II kerogen with lesser amounts of types I and III, such that petroleum generation ranges from ‘fair’ to ‘excellent’ in general terms. With the exception of Es1 (uppermost member), which is immature to marginally mature for oil generation, the sequence studied ranges from ‘mature for oil generation’ to ‘mature for wet gas generation’. On the basis of vitrinite reflectance data, the most prospective depths for shale oil/condensate generation are between ~ 2300 and 4000 m depth in area studied. The saline mudstones comprise mainly clay minerals, followed by carbonates, quartz and feldspar. Based solely on the ‘brittle mineral index’, the amounts of carbonate and quartz in many of the samples lead to a similar, or greater suitability for hydraulic fracturing than for many Haynesville, Woodford and upper Bakken shales. SEM studies show that abundant micro-fractures commonly occur in the mudstones and these include tectonic fractures, bedding plane fractures, shrinkage fractures, and over-pressured fractures. For the Es3 M (middle third member) unit, shale oil prospectivity is likely to be enhanced around the towns of WL (Wenliu), LT (Liutun) and HBZ (Hubuzhai), due to the increased frequency of tectonic fractures, which would contribute to oil storage and flow. Mineral interparticle, mineral intraparticle and organic matter pores are well developed in the rocks studied. Mineral dissolution has created secondary pores in some areas, such that reservoir capacity is increased. The increased concentration of organic acids between 2800 and 3500 m is likely to lead to enhanced shale oil prospectivity. The micro-fractures and dissolution pores are probably the main reservoirs for shale oil accumulation. The association of these features with saline facies potentially offers an exploration tool for further shale oil occurrences in the studied area, as well as in other areas containing similar lithologies. [ABSTRACT FROM AUTHOR]

Abstract: Three new dye-doped inorganic-organic hybrid microtubes, SiMW11-F (M = W, Mo and V; F = fluorescein), have been obtained and characterized by X-ray diffraction, ultraviolet/visible spectroscopy, elemental analysis, thermogravimetric analysis. Comparative studies have been carried out on fluorescent properties of the three SiMW11-F microtubes and fluorescein. These fluorescent hybrid microtubes exhibit luminescent emission properties which are different from raw material fluorescein in the blue spectral region, which is suggests that different luminescence centers may be formed in the hybrid microtubes. The SiW12-F and SiMoW11-F microtubes show more similar fluorescent properties than the SiVW11-F microtubes, due to the differences in ionic radius and oxidation state between W/Mo and V. Furthermore, the three polyoxometalate components in the microtubes exhibit an inhibiting effect on photobleaching of fluorescence dye in the reaction system. [Copyright &y& Elsevier]

Abstract: A new inorganic–organic hybrid compound constructed from Keggin-type polyoxometalate and cadmium-organic units, namely, [Cd(Htrz)3]2[SiW12O40]·2H2O (1), [Htrz=1-H-1,2,4-triazole], has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, IR, TG, and UV–vis absorption spectra. In compound 1, each [SiW12O40]4− cluster is modified by six [Cd(Htrz)3]2+ metal–organic fragments, meanwhile, each [Cd(Htrz)3]2+ also connects with three [SiW12O40]4− to built up a binodal (3,6)-connected 2D planar network with the (43)2(46·66·83)-kgd topology. Interestingly, [SiW12O40]4− cluster exhibits a rare coordination mode acting as a hexadentate ligand, in which all of the six terminal oxygen atoms in the equatorial plane are synchronously participated in coordination. The diffuse reflectivity spectrum shows it can be regarded as a wide gap semiconductor. Moreover, the photocatalytic performance shows good photocatalytic activity for the degradation of Rhodamine B. [Copyright &y& Elsevier]

Abstract: Two isostructural compounds based on Anderson polyoxoanions, [Cu(phen)]2[CrMo6H5O24] (1) and [Cu(phen)]2[AlMo6H5O24] (2) (phen=1,10-phenaanthroline), have been hydrothermally synthesized and characterized by IR, XPS, EPR spectra, TG analyses, magnetic susceptibility, and single-crystal X-ray diffraction. Compounds crystallize in the monoclinic space group P2(1)/n with a =5.66710(10)Å, b =21.3723(5)Å, c =14.7092(3)Å, β =98.10(10)°, V =1763.79(6)Å3, R 1 =0.0240, Z =2 and GOF =1.140 for 1, and in the monoclinic space group P2(1)/n with a =5.6641(3)Å, b =21.3346(13)Å, c =14.6909(9)Å, β =97.9120(10)°, V =1758.37(18)Å3, R 1 =0.0529, Z =2 and GOF =0.0994 for 2. Single crystal X-ray diffraction reveals that the compounds 1 and 2 are both built up of Anderson polyoxoanions and copper–phen complexes. The structural feature of 1 and 2 is that the Anderson polyoxoanions act as multidentate ligands linking copper–phen complex to form 1D chains. Compounds 1 and 2 not only represent new Anderson-type POM-supported transition metal organic–inorganic hybrid compounds with extend structure, but also verify the feasibility of constructing these compounds through hydrothermal methods. [Copyright &y& Elsevier]

Abstract: Micro-formaldehyde gas sensor of palladium doped tin dioxide was fabricated on silicon substrate. Finite element software ANSYS was used to analyze the thermal field distribution. In order to obtain a uniform thermal field distribution in the micro-gas sensor, the width of the marginal four strips of the heating electrode was designed to be 50μm and the width of the central seven strips 25μm. Undoped and 1mol% Pd-doped SnO2 thin films were synthesized by sol–gel method on silicon substrates. XRD and XPS spectra of the films were analyzed. The response of the 1mol% Pd-doped SnO2 micro-gas sensor to formaldehyde was much higher than that of the undoped SnO2 micro-gas sensor. This experimental observation was also supported by the XPS O (1s) patterns of the films which showed that doping 1mol% Pd into SnO2 increased the value of Oa/Ol, i.e., the ratio of adsorption and lattice oxygens. Formaldehyde of 0.03ppm concentration was detected by the 1mol% Pd-doped SnO2 micro-gas sensor. [Copyright &y& Elsevier]

A novel three-dimensional inorganic bimetallic compound Cu[Mo3O10]·H2O 1 has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in the orthorhombic system, space group Pnma, a=8.6085(17) A˚, b=7.5822(15) A˚, c=13.690(3) A˚, V=893.6(3) A˚3, Z=4, λ(MoKα) = 0.71073 A˚ (R(F)=0.0357 for 1101 reflections). The structure of compound 1 is based on [{Mo3O10}2−]∞ isopolyoxomolybdate chains bonded together with CuO4 tetrahedra into a three-dimensional inorganic open framework. Three types of Mo–Cu layers and one-dimensional tunnels are observed in the title compound. [Copyright &y& Elsevier]

A novel compound, [Co(phen)3][V10O26]·H2O, was hydrothermally synthesized and characterized by single-crystal X-ray diffraction. This compound crystallizes in the orthorhombic space group Ccca with a=13.447(3), b=29.936(6), c=23.252(5) A˚, V=9360(3) A˚3, Z=8 and R=0.0285. Data were collected on a Rigaku R-AXIS RAPID IP diffractometer at 293 K in the range of 1.36<θ<24.99°. The structure of the compound consists of vanadium oxide layers, which are built up from the infinite VO4 chains by corners and edges sharing. The [Co(phen)3]2+ complexes occupy the interlayer space and contact each other via π−π stacking interactions of the phen groups to form infinite one-dimensional chains. [Copyright &y& Elsevier]