Proton-Conductive Polyoxometalate Architectures Constructed from Lanthanide-Incorporated Polyoxoniobate Cages.

Two new extended polyoxometalate (POM) architectures based on lanthanide-incorporated polyoxoniobate (Ln-incorporated PONb) cages, namely, H4[CuII(en)2]4{K4(H2O)2[CuII(en)2]5[CuII5(trz)2(en)4(OH)2][Dy2CuII2(en)2(CO3)3(H2O)2(OH)3][Dy(H2O)4][DyNb23O68(H2O)4]2}·60H2O (1, en = ethylenediamine) and H20[CuII(en)2]4{[CuII(en)2]4[Dy2(C2O4)(H2O)4]2[(Nb32(OH)4(H2O)3O89]2}·54H2O (2), have been successfully synthesized and structurally characterized, demonstrating a feasible strategy to develop functional POM materials. In addition, the proton conductivity and magnetic behaviors of both 1 and 2 were studied.

Two high-nuclearity isopolyoxoniobates containing {Nb54 O151}-based helical nanotubes for the decomposition of chemical warfare agent simulants.

Two inorganic-organic hybrid isopolyoxoniobates (1 and 2) based on new high-nuclearity {Nb54O151} clusters have been synthesized under hydrothermal conditions. In particular, the combination of the unique {Nb54O151} clusters with copper-amine complexes has led to rare helical nanotubes, which are further linked by alkali metal cations or copper-amine complexes into two 2D similar bamboo-raft-like layered networks (1 and 2), respectively. Compound 1 exhibits effective base-catalytic decomposition of chemical warfare agent simulants dimethyl methylphosphonate (DMMP) and diethyl cyanophosphonate (DECP).

High-dimensional Polyoxoniobates Constructed from Lanthanide-incorporated High-nuclear {[Ln(H2 O)4 ]3 [Nb24 O69 (H2 O)3 ]2 } Secondary Building Units.

In this work, two rare high-dimensional polyoxoniobates with formulas of H9 [Cu(en)(H2 O)2 ][Cu(en)2 ]8 [Dy(H2 O)4 ]3 [Nb24 -O69 (H2 O)3 ]2 ⋅ 36H2 O (1) and H9 K[Cu(en)2 (H2 O)]5 [Cu(en)2 ]4 -[Eu(H2 O)4 ]3 [Nb24 O69 (H2 O)3 ]2 ⋅ 2en ⋅ 45H2 O (2) have been obtained under hydrothermal conditions. These extended materials are constructed from lanthanide-incorporated triangular-prism-like polyoxoniobate secondary building units (SBUs) {[Ln(H2 O)4 ]3 [Nb24 O69 (H2 O)3 ]2 } (Ln=Dy, Eu). 1 and 2 represent the first examples of high-dimensional polyoxometalate materials based on such lanthanide-incorporated triangular-prism-like polyoxoniobate SBUs. Furthermore, the proton conduction property and the luminescent emission of these materials were evaluated.

A Series of Cube-Shaped Polyoxoniobates Encapsulating Octahedral Cu12X m O n Clusters With Hydrolytic Decomposition for Chemical Warfare Agents.

This study reported a series of cube-shaped polyoxoniobates, {MCu12O8)(Cu12XmOn)(Nb7(OH)O21)8} [M = Nb(1, 2), Ln3+(3), X = I(1, m = 3, n = 3; 2, m = 5, n = 1), Br(3, m = 5, n = 1)]. As the first octahedral Cu12XmOn cluster incorporated polyoxoniobate, the cube-shaped three-shell structure of {MCu12O8)(Cu12XmOn)(Nb7(OH)O21)8} polyanion contains a {MCu12O8} body-centered cuboctahedron, a {Cu12XmOn} octahedron and a {Cu12(Nb7(OH)O21)8} cube. Compounds 1, 2, 3 show effective catalytic activities for the hydrolytic decomposition of chemical warefare agent simulants.

A Chromium-Substituted Polyoxoniobate with High Ionic Conductivity.

A rare and novel Cr-substituted polyoxoniobate (PONb), [Cr2.5Nb27.5O66(OH)20(H2O)2]7-, has been synthesized by a combination of hydrothermal and conventional solution methods. The PONb shows an unknown tetrameric structure, which is the largest Cr-containing PONb to date. Interestingly, every two PONb tetramers can be joined together by alkali-metal cations to form a discrete cubelike ionic cluster. The obtained PONb not only enriches the very limited members of the Cr-substituted PONb family but also exhibits high ionic conductivity.

{Nb288 O768 (OH)48 (CO3 )12 }: A Macromolecular Polyoxometalate with Close to 300 Niobium Atoms.

A protein-sized (ca. 4.2×4.2×3.6 nm3 ) non-biologically derived molecule {Nb288 O768 (OH)48 (CO3 )12 } (Nb288 ) containing up to 288 niobium atoms has been obtained, which is by far the largest and the highest nuclearity polyoxoniobate (PONb). Particularly, in terms of metal nuclearity number, Nb288 is the second largest cluster so far reported in classic polyoxometalate chemistry (V, Mo, W, Nb, and Ta). Nb288 can be described as a giant windmill-like cluster aggregate of six nanoscale high-nuclearity PONb units {Nb47 O128 (OH)6 (CO3 )2 } (Nb47 ) joined together by six additional Nb ions. Interestingly, the 47-nuclearity Nb47 units generated in situ can be isolated and bridged by copper complexes to form an inorganic-organic hybrid three-dimensional PONb framework, which exhibits effective catalytic activity for hydrolyzing nerve agent simulant of dimethyl methylphosphonate. The unique Nb47 cluster also provides a new type of topology to very limited family of Nb-O clusters.

A Series of Banana-Shaped 3d-4f Heterometallic Cluster Substituted Polyoxometalates: Syntheses, Crystal Structures, and Magnetic Properties.

Four seven-nuclearity 3d-4f heterometallic cluster {Fe6LnO28} substituted polyoxometalates (HPz)11K4Fe6Ln(µ3-O)2(B-α-GeW9O34)2(GeW6O26)· xH2O (1-Ln, Pz = piperazine, Ln = Tb, Dy, Ho, Er for x = 27, 25, 25, 24, respectively) have been hydrothermally prepared and structurally characterized by single-crystal X-ray diffraction, powder X-ray diffraction, infrared spectrometry, thermogravimetric analyses, elemental analyses, and electrospray ionization mass spectrometry. Single-crystal X-ray diffraction analyses revealed that 1-Ln contain an unprecedented banana-shaped polyanion constructed from an iron-lanthanide heterometallic {Fe6LnO28} cluster, two trilacunary {B-α-GeW9O34} units, and one hexalacunary {GeW6O26} fragment. The magnetic susceptibility surveying proved the presence of antiferromagnetic coupling in 1-Ln.

Record High-Nuclearity Polyoxoniobates: Discrete Nanoclusters {Nb114 }, {Nb81 }, and {Nb52 }, and Extended Frameworks Based on {Cu3 Nb78 } and {Cu4 Nb78 }.

A series containing the highest nuclearity polyoxoniobate (PONb) nanoclusters, ranging from dimers to tetramers, has been obtained. They include one 114-nuclear {Li8 ⊂Nb114 O316 }, one 81-nuclear {Li3 K⊂Nb81 O225 }, and one 52-nuclear {H4 Nb52 O150 }. The Nb nuclearity of these PONbs is remarkably larger than those of all known high-nuclearity PONbs (≤32). Furthermore, the introduction of 3d Cu2+ ions can lead to the generation of extended inorganic-organic hybrid frameworks built from novel, high-nuclearity, nanoscale heterometallic PONb building blocks {H3 Cu3 Nb78 O222 } or {H3 Cu4 (en)Nb78 O222 }. These building blocks also contain the largest number of Nb centers of any heterometallic PONbs reported to date. The synthesis of new-type PONbs has long been a challenging subject in PONb chemistry.

[Spatial characteristics analysis of Huizhou-Styled Village based on ideal ecosystem model and 3D landscape indices: A case in Chengkan, China]. / 基于理想生态系统模式与三维景观指数的徽派村落空间特征解析­­ä»¥å‘ˆåŽä¸ºä¾‹.

Huizhou-Styled Village is a typical representative of the traditional Chinese ancient villages. It preserves plentiful information of the regional culture and ecological connotation. The Huizhou-Style is the apotheosis of harmony between the Chinese ancient people and nature. The research and protection of Huizhou-Styled Village plays a very important role in fields of ecology, geography, architecture and esthetics. This paper took Chengkan Village of Anhui Province as an exa-mple, and proposed a new model of ideal ecosystem oriented in theories of Feng-shui and psychological field. The new method of characterizing 3D landscape index was introduced to explore the spatial patterns of Huizhou-Styled Village and the functionality of the composited landscape components in a quantitative way. The results indicated that, Chengkan Village showed a spatially composited pattern of "mountain-forest-village-river-forest". It formed an ideal settlement ring structure with human architecture in the center and natural landscape around in the horizontal and vertical horizons. The traditional method based on the projection distance caused the deviation of the landscape index, such as underestimating the area and distance of landscape patch. The 3D landscape index of average patch area was 6.7% higher than the 2D landscape index. The increasing rate ofarea proportion in 3D index was 1.0% higher than that of 2D index in forest lands. Area proportion of the other landscapes decreased, especially the artificial landscapes like construction and cropland landscapes. The area and perimeter metric were underestimated, whereas the shape metric and the diversity metric were overestimated. This caused the underestimation of the dominance of natural patches was underestimated and the overestimation of the dominance of artificial patches during the analysis of landscape pattern. The 3D landscape index showed that the natural elements and their combination in Chengkan Village ecosystem reflected better ecological function, the key elements and the composited landscape ecosystem preserved higher stability, connectivity and aggregation. The quantitative confirmation showed that the Huizhou-Styled Village represented by Chengkan Village is an ideal ecosystem.

[Impacts of high-volume hemofiltration on hemodynamics and vascular endothelial permeability in children with septic shock].

OBJECTIVE: To investigate the effects of high-volume hemofiltration (HVHF) on hemodynamics, vasoactive factors, and vascular endothelial permeability in children with septic shock by a comparative analysis. METHODS: Thirty-six children who were diagnosed with septic shock between January 2013 and September 2014 were randomly divided into control and observation groups (n=18 each). Children in the control group were treated with the standard-volume hemofiltration (SVHF), while children in the observation group were treated with HVHF. The hemodynamic indices and levels of vasoactive factors including 6-keto-prostaglandin F1α (6-keto-PGF1α), thromboxane B2 (TXB2), soluble E-selectin (sE-selectin), and endothelium-derived relaxing factor (EDRF) were determined before and after treatment. In addition, the effects of ultrafiltrate on endothelial cell permeability were assessed. RESULTS: Compared with the control group, the observation group had significantly higher mean arterial pressure, significantly higher blood oxygen saturation, and a significantly lower heart rate after treatment (P<0.05). The levels of TXB2 and sE-selectin were significantly lower in the observation group than in the control group (P<0.05), while the levels of 6-keto-PGF1α and EDRF were significantly higher in the observation group than in the control group (P<0.05). Compared with the control group, the ultrafiltrate significantly attenuated the transepithelial electrical resistance in the observation group (P<0.05). CONCLUSIONS: Compared with SVHF, HVHF is a more effective approach for improving the hemodynamics and levels of vasoactive factors and reducing the vascular endothelial permeability in children with septic shock.