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A series of polyoxometalates (POMs)-based coordination polymers are synthesized through direct incorporation between POMs and the voids of the two-dimensional (2D) network. The crystal structural analysis has shown that the relationship between the size of the void of the 2D network and that of POMs is very important for the synthesis of POMs-based open metal-organic frameworks.

Three sandwich-type silicotungstates, formulated as [Cu4(H2O)2(SiW9O34)2]·12NH4·22H2O (1), [Cu4(H2O)2(SiW9O34)2]·12NH4·11H2O (2) and {[Cu(NH3)4]2[Cu(H2O)4][Cu4(H2O)2(SiW9O34)2]} 2[Cu(NH3)4(H2O)]·2NH4·6H2O (3), were synthesized by microwave irradiation and hydrothermal reaction. Crystal structural analysis reveals that 1–3possess the same dimeric polyoxoanions [Cu2SiW9O34(H2O)]212−featuring tetranuclear copper(ii) clusters. Magnetic studies indicate that the Cu4clusters exhibit ferromagnetic coupling interactions. Investigation on their catalytic activity for the oxidation of ethylbenzene suggests that catalytic activity of 1–3is closely related to the acidity of complexes and the existence of unsaturated coordination sites in the complex. [ABSTRACT FROM AUTHOR]

In the title compound, [Na6(NO3)2(H2O)13][Ni(C14H18N2O8)]2, the edta-like tetraanionic unit uses two N and four O atoms to chelate to the Ni atom so that the [Ni(C14H18N2O8)]2− portion of the structure has the Ni atom in a cis–N2O4Ni octahedral geometry. The [Na6(NO3)2H2O)13]4+ portion exists as a chain consisting of edge-sharing NaO6 octahedra; there are four independent Na atoms in the asymmetric unit. The vertices are derived from the O atoms of water mol­ecules, the O atom of the nitrate group as well as the O atoms of the [Ni(C14H18N2O8)]2− unit. The layer structure is consolidated by hydrogen bonds into a three-dimensional network. Two of the Na atoms and three of the water O atoms lie on special positions of site symmetry 2. [ABSTRACT FROM AUTHOR]

Famous traditional formula Sanpian Decoction(SPD)comes from Dialectical Records of Chen Shiduo of the Qing Dynasty,and ranks among 100 classic prescriptions of Classic Famous Traditional Formula catalogue(the First Batch). SPD was prepared according to Management Standards for Traditional Chinese Medicine Decoction Room in Medical Institutions. According to the polarity of different components in SPD,two HPLC fingerprints were established, in which six herbs, namely Chuanxiong Rhizoma, Paeoniae Randix Alba, Sinapis Semen, Glycyrrhizae Radix et Rhizoma, Pruni Semen, Angelicae Dahuricae Radix,are all reflected in the fingerprints; The dry extract rate, transfer rate and similarities of fingerprints were used as indicators to study the relationship between the quality value transmitting of medicinal herbs-decoction pieces-whole decoction of Chuanxiong Rhizoma. Experiment result shows that,the transfer rate of ferulic acid from medicinal herbs to decoction pieces is between 72.00% and 108.36%; the transfer rate of ferulic acid from decoction pieces to SPD is between 31.76% and 64.09%; the dry extract rate of the whole decoction is between 14.69% and 20.16%;The similarity range of fingerprint 1 of 15 batches of SPD is between 0.971 and 0.998, and the similarity range of fingerprint 2 is between 0.980 and 0.996. The established fingerprint has rich information,and the established quality evaluation method is suitable for the quality control of medicinal herbs-decoction pieces-whole decoction of Chuanxiong Rhizoma, which can provide a certain reference for developing the quality control evaluation method for formulated granules, famous formulae and other terminal products derived from traditional Chinese medicine decoction.

In recent years,the development and application of classical famous prescriptions have attracted much attention. However,the differences between ancient and modern conditions lead to difficulties in carrying out practical work. In this paper,with Houpu Wenzhong Decoction as an example,the key technologies of boiling granularity,water addition,boiling time and sample pretreatment methods were investigated on the basis of sufficient literature research. The experimental results showed that there was no significant difference in the concentration of index components between those with different granularity( 2 mm and 3-5 mm) and different decocting time( 30 min and 60 min),but the extraction rate of index components was relatively high when the granularity of powder was 2 mm and decocting time was 30 min. With the increase of water content,the concentration of index components and the extraction rate were increased in varying degrees. A certain proportion of methanol aqueous solution was used as the resolvent before content determination of the reference sample of Houpu Wenzhong Decoction,which could take into account both the spectral information of water-soluble components and fat-soluble components in the prescription,and help to display the overall information of the prescription' s chemical components more comprehensively. At the same time,the boiling and dispersing classical prescriptions in the Catalogue of Ancient Classical Prescriptions( the first batch) were collected and summarized in this study; the key influencing factors of decocting process were analyzed from different angles,and preliminary research suggestions were put forward,so as to provide a certain direction and reference for the establishment of quality standard of Houpu Wenzhong Decoction,as well as for the development,research and clinical application of boiling and dispersing classical prescriptions.

We investigate the electronic and magnetic properties of K(x)Fe(2-y)Se2 materials at different band fillings utilizing the multi-orbital Kotliar-Ruckenstein slave boson mean-field approach. We find that the ground state of KFe2Se2 is a paramagnetic (PM) bad metal with intermediate correlation, in contrast with the previous antiferromagnetic (AFM) results obtained by the local density approximation. Our PM metallic ground state suggests that KFe2Se2 is the parent phase of superconducting K(x)Fe(2-y)Se2, supporting a recent scanning tunneling spectroscopy experiment. For pure Fe2+-based systems, the ground state is a striped AFM (SAFM) metal with a spin density wave gap partially opened near the Fermi level. In comparison, for Fe3+-based compounds, besides SAFM, a Néel AFM metal without orbital ordering is observed, and an orbital selective Mott phase (OSMP) accompanied by an intermediate-spin to high-spin transition is also found, giving a possible scenario of an OSMP in K(x)Fe(2-y)Se2. These results demonstrate that the band filling and correlation control the Fermi surface topology, electronic state and magnetism in K(x)Fe(2-y)Se2.