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A unique metal-organic framework (MOF) with tetrazole-padded helical channels has been successfully synthesized in one pot from iron(II) trifluoromethanesulfonate, 4-formylimidazole, hydrazine, and sodium azide under solvothermal conditions and features a rare unh topology and porous structure for gas adsorption. Transformations of condensation, cycloaddition, and coordination occurred during the synthetic process, in which a 1,5-disubstituted tetrazole ligand was formed in situ.

As a creation platform for multifunctional materials, crystalline metal–organic frameworks (MOFs) can integrate different chromophores through reticular chemistry to adjust their spatial arrangement and intermolecular interaction, in turn achieving the purpose of improving the nature of optoelectronic properties. Herein, a stepwise reticular synthesis approach is successfully used to construct a multicomponent MOF, in which the well-known bis-terpyridyl ruthenium chromophore is orderly arranged into the skeleton of the material. Remarkably, this method promotes the excited state lifetime of the bis-terpyridyl ruthenium core, by two orders of magnitude (from 0.39 to 22.09 ns), to the extent that it can produce singlet oxygen under visible light irradiation at room temperature. Meanwhile, the obtained multicomponent MOF has been established to have considerable porosity for exposure of substrates to the catalytic sites, rendering it suitable for heterogeneous photocatalysis, including as a photooxidation detoxifier for sulfur mustard simulant. Moreover, DFT and TDDFT calculations reveal that the synergistic charge transfer among different components in the MOF may play a crucial role in improving the excited state properties of the bis-terpyridyl ruthenium motif.

A triangular prismatic metal-organic cage based on mixed valence copper ions has been designed and synthesized by using metallocycle panels and pillar ligands. The triangular prism will be quickly transformed to a 10-nuclear cage upon an external chemical stimulus, which features a bicapped square antiprism structure. This prismatic cage can act as a catalyst for oxidation of aromatic alcohols to their corresponding aromatic aldehydes with high yields at room temperature under O2 atmosphere.

To analyze the genotype characteristics of α- and β-thalassemia and the diagnostic value of hematological indexes in pregnant women in Xindu District of Chengdu.The blood routine parameters(MCV)80 fl and (or) (MCH)27 pg and hemoglobin electrophoresis were used to screen the pregnant women, PCR-reverse dot blot hybridization(PCR-RDB) technique was used to detect the common α- and β-thalassemia gene types in the primary screening positive population. The husbands of the diagnosed pregnant women were recalled for gene testing, and the highly suspected patients were checked by gene sequencing.Among the 7 049 pregnant women, 1 740(24.68%) cases were positive for primary screening. 180 patients were diagnosed as thalassemia gene positive, among them, 94 cases (52.22%) of α-thalassemia were detected and six genotypes were found, in which --The most common genotypes of α- and β-thalassemia in pregnant women in Xindu District of Chengdu were --成都市新都区孕妇地中海贫血基因检测结果及血液学指标应用价值.分析成都市新都区孕妇α、β地中海贫血的基因型特点及各血液学指标的诊断价值.采用血常规参数（MCV）80 fl和（或）（MCH）27 pg及血红蛋白电泳对孕妇进行初筛，初筛阳性者采用PCR-反向斑点杂交检测技术进行常见α、β地中海贫血基因检测，对于确诊为地贫孕妇，召回其丈夫直接进行地贫基因检测，对高度疑似患者进行基因测序复核结果.7 049例孕妇中，初筛阳性1 740例（24.68%）。地贫基因确诊阳性180例，其中α地中海贫血94例（52.22%），共检出6种基因型，基因型--成都市新都区孕妇α、β地中海贫血基因类型主要以

Gas separation performances are usually degraded under humid conditions for many crystalline porous materials because of the lack of water stability and/or the competition of water vapor toward the interaction sites (e.g., open metal sites). Zeolitic imidazolate frameworks (ZIFs) are suitable candidates for practical applications in gas separation because of their excellent physical/chemical stabilities. However, the limitation of substituent positions in common ZIFs has prevented extensive pore engineering to improve their separation performance. In a type of gyroidal ZIFs with

SUMMARY Uniaxial compression tests with combined acousto-optical monitoring techniques are conducted on flawed granite specimens, with the aim of investigating the fracture-related acoustic emission (AE) event rate characteristics at the unstable cracking phase in flawed rocks. The interevent time (IET) function F(τ) is adopted to interpret the AE time-series from damage stress (σcd) to ultimate failure, and photographic data are used to evaluate unstable cracking behaviours in flawed granite. The results show that a high AE event rate is always registered but intermittently interrupted by macrofracturing at the unstable cracking phase. The reversed U-shaped curve relation between the AE event rate and the loading time is documented in unstable flawed granite for the first time. The acoustic quiescence has a mechanismic linkage and quantitative correlation with stress drop, and this synchronous acousto-mechanical behaviour is a typical result of the initiation, growth and coalescence of macrocracks initiated from the flaw tips. Moreover, the reactivation and intensification of fracture process zones (FPZs) by increasing loads are the dominant mechanism triggering unstable crack growth in flawed granite.

Polynuclear silver clusters are described that unexpectedly transform from cyclic trinuclear complexes (CTCs) upon reacting with σ-donating phenylacetylene, featuring a noria-like conformation. The introduction of foreign copper ions leads to isomorphic bimetallic Ag/Cu clusters, with a boost in the photoluminescence quantum yield relative to the original silver clusters.

Two mixed-valence CuII/CuI and two heterometallic CuII/AgI metallocycles have been synthesized by the assembly of designed metalloligands and CuI/AgI ions, respectively. The CuII/CuI metallocycle can catalyze the oxidation of alcohols to aldehydes mediated by a co-catalyst, TEMPO (2,2,6,6-tetramethylpiperdine-1-oxyl), with ambient air as an oxidant, while the CuII/AgI metallocycle has no catalytic effect.

Metalloenzymes are powerful biocatalysts that can catalyze particular chemical reactions with high activity, selectivity, and specificity under mild conditions. Metal-organic frameworks (MOFs) composed of metal ions or metal clusters and organic ligands with defined cavities have the potential to impart enzyme-like catalytic activity and mimic metalloenzymes. Here, a new metal-organic framework implanted with hydroxo iron(III) sites with the structural and reactivity characteristics of iron-containing lipoxygenases is reported. Similar to lipoxygenases, the hydrogen atoms and electrons of the substrate can transfer to the hydroxo iron(III) sites, showing typical proton-coupled electron transfer behavior. In the reactivity mimicking biology system, similar to alcohol oxidase, the material also catalyses the oxidation of alcohol into aldehyde by using O2 with a high yield and 100% selectivity under mild conditions, without the use of a radical cocatalyst or photoexcitation. These results provide strong evidence for the high structural fidelity of enzymatically active sites in MOF materials, verifying that MOFs provide an ideal platform for designing biomimetic heterogeneous catalysts with high conversion efficiency and product selectivity.

Charge separation plays a crucial role in regulating photochemical properties and therefore warrants consideration in designing photocatalysts. Metal-organic frameworks (MOFs) are emerging as promising candidates for heterogeneous photocatalysis due to their structural designability and tunability of photon absorption. Herein, we report the design of a pyrazole-benzothiadiazole-pyrazole organic molecule bearing a donor-acceptor-donor conjugated π-system for fast charge separation. Further attempts to integrate such a photosensitizer into MOFs afford a more effective heterogeneous photocatalyst (JNU-204). Under visible-light irradiation, three aerobic oxidation reactions involving different oxygenation pathways were achieved on JNU-204. Recycling experiments were conducted to demonstrate the stability and reusability of JNU-204 as a robust heterogeneous photocatalyst. Furthermore, we illustrate its applications in the facile synthesis of pyrrolo[2,1

The exploration of highly efficient materials for the degradation of chemical warfare agents has been a longstanding task for preventing human exposure. Herein, we report a series of metal-organic frameworks (MOFs) M-TCPP-La based on metallo-tetra(4-carboxyphenyl)porphyrin and LaIII, which were applied to selectively oxidize 2-chloroethyl ethyl sulfide (CEES, a sulfur mustard simulant) as heterogeneous photocatalysts. After irradiation from a commercial blue light-emitting diode (LED), both superoxide ion and singlet oxygen were generated by M-TCPP-La and involved in selective oxidization of CEES to 2-chloroethyl ethyl sulfoxide (CEESO). Notably, a very short half lifetime (2.5 min) was achieved using Fe-TCPP-La as the photocatalyst. In comparison to currently utilizing singlet oxygen and hydrogen peroxide as oxidizing agents, this work employing both singlet oxygen and superoxide ion represents a new and effective strategy of detoxification of mustard gas.

To evaluate the pollution by polycyclic aromatic hydrocarbons (PAHs) in the surface soil of the core urban area of Lanzhou, 62 topsoil samples were collected from the area. The soil samples were analyzed for the content of 16 priority PAHs, using gas chromatography-mass spectrometry. Descriptive statistical methods were used to characterize contamination by PAHs. An absolute principal component analysis-multiple linear regression (APCS-MLR) model was applied to determine the sources of PAHs in the soil samples, and the accuracy of the model results was verified. Finally, the main influence regions of each source were determined with a geo-statistical method. The results showed that the contents of Σ

The SiF62- anions are in situ formed in the reactions of MF2 (M = Cu2+, Zn2+, Ni2+, and Co2+) salts and nitrogen-containing ligands in borosilicate glass tubes under solvothermal conditions and then used to further construct a family of metal-organic frameworks (MOFs). This in situ reaction demonstrates a new and facile strategy for the fabrication of MOFs based on SiF62-.

By coupling the phantom node method with the mesh cut technique in the framework of the extended finite element method (XFEM), an enhanced XFEM for the propagation of complex branched cracks is proposed. The proposed method aims to solve the complex branched crack problems. Additionally, instead of the constant crack propagation length, a novel crack propagation scheme is introduced into the XFEM, in which the crack propagation length is a variable which is determined by two trial calculations. The feasibility and the accuracy of the proposed method are validated by numerical tests. The numerical results show that the enhanced XFEM can easily handle the complex branched crack problems, and it has the higher accuracy than the standard XFEM. Meanwhile, a smooth crack path can be obtained using the novel crack propagation scheme.

Metal-organic cages are potential artificial models for mimicking biological functions due to their capability of selective encapsulation for certain guest molecules. In this work, we designed and synthesized a series of rhombic dodecahedral Ni-imidazolate cages (Ni

A family of polyhedral metal-imidazolate cages based on the flexible bi-imidazole ligand L and Cu2+ ions have been synthesized and characterized, featuring an unusual Cu10L8 bicapped square antiprism structure (or Johnson solids, J17) with an adaptable cavity. These metal–organic cages encapsulate anions, and they will expand or compress after they are filled with different-sized anions.

Gyroid materials have received considerable attention from scientists due to their beautiful structures and advanced functions. On the other side, metal–organic frameworks are inorganic–organic hybrid crystalline porous materials with atomic precision, and can provide good structural models and rich topologies for gyroid materials. In this review, we will briefly introduce the structures of gyroid metal–organic frameworks and their topologies. In addition, their applications in gas adsorption, catalysis, sensors, and luminescent materials are also discussed in detail.

Understanding the mechanical properties plays pivotal roles in rock engineering. This work aims to establish novel relations linking the porosity, ultrasonic wave and fluid saturation to estimate the uniaxial compressive strength (UCS) fast and simply. The uniaxial compressive coupled with ultrasonic wave tests on sandstone samples are carried out to obtain the datasets of the UCS, P-wave and S-wave velocities. X-ray CT imaging technique is employed to capture the microstructure information. The color difference phase separation approach to segment the pore, water and solid phases is proposed, and pore-scale variables to describe the microstructure characteristics are defined. Novel relations to determine the micro velocities of P-wave and S-wave are established, and the modulus of deformation and the physical properties of rocks are evaluated. Novel relation to determine the UCS is established and validated by the real and virtual experiment datasets. Results show that the UCS, P-wave and S-wave velocities computed by the proposed method decrease with increasing fluid saturation. The errors between the calculated and experimental UCS, P-wave and S-wave velocities are all

A pair of enantiomers of three-dimensional (3D) chiral coordination polymers (CCPs) were successfully constructed by using achiral components 4,2':6',4''-terpyridyl precursors and Cu2+ through spontaneous resolution (1 a). By utilising feeding controlled chiral-templated induction and chiral auxiliary behaviour of optically pure camphor sulfonate (CSA), the enantioenriched (1 b-P and 1 b-M) and CSA captured (1 c-P and 1 c-M) CCPs were successfully synthesised, respectively. The chiral information of the corresponding products was confirmed by X-ray single crystal diffraction and solid-state CD spectra. Meanwhile, the formation processes of 1 b-P and 1 b-M were monitored through solution CD spectra, UV/Vis spectra and ESI-TOF MS. Based on these results, a reasonable chiral-templated induction mechanism of forming 1 b-P and 1 b-M was proposed.

A variety of planar organic fluorophores (R=phenyl, naphthalenyl, pyrenyl) and luminescence promotors (X=Cl, Br, I) were equipped, respectively, on the alternatively arranged vertices of cubic ZnII -imidazolate cages through orthogonal subcomponent self-assembly. It was found that supramolecular interactions, especially weak C-H⋅⋅⋅X interactions, play a key role in activating an efficient radiative pathway, coupled with reduced nonradiative decay rate through metal coordination, therefore significantly boosting the emission quantum yields of the system. This finding provides a strategy that utilizes molecular geometry and supramolecular interactions to modulate the emission efficiency of luminescent cage-based materials.

Using water as the sole solvent, the bifunctional molecule tetrakis(methylthio)-1,4-benzenedicarboxylic acid (TMBD) was reacted with Cu(CH3CN)4BF4 to form a robust microporous metal-organic framework (MOF, CityU-7) featuring Cu(I) ions being simultaneously bonded to the carboxyl and thioether donors. The MOF solid is stable in air and can be easily activated by heating, without the need for treatment with organic solvents. The subnanoscopic pores (ca. 0.6 nm) of the host net allow for uptake of CO2 and H2O but exhibit lesser sorption for N2 at 77 K. The microporous net can also be penetrated by I2 molecules.

This paper details a method for investigating the stability of a layered slope that combines random field theory with horizontal integration. Both the cohesion and friction coefficient are treated as a Gaussian random field. The closed-form solution of the factor of safety and the probability of failure of the layered slope are derived, in which the effects of spatial correlation lengths and spatial correlation parameters on the stability of the layered slope are considered. The derived probability of failure is greatly affected by the input spatial correlation length of the soil parameters. The effectiveness of this proposed method is validated with the results of the Monte Carlo simulation.

Three coordination polymers (CPs) with square-planar CuII/NiIIN4 subunits were formed in one step by subcomponent self-assembly, giving rise to an unprecedented linking variety of in situ embedded metalloligands and CuI clusters. All CPs exhibit unusual visible-light adsorption. Enhanced photocatalytic activity and high selectivity were observed in the oxidation of benzene under visible-light irradiation.

In this work, Zn2+ and Cu2+ ions are doped into a Mn2+ based frail MOF (STU-2) to form heterometallic MOFs. These metal doped MOFs show a good stability and heterogeneous catalytic activity for the cyanosilylation reactions of aromatic aldehydes. The catalysts can be reused at least for three cycles.

In contrast to the regular postsynthetic modification (PSM) approach which is global and random in principle, a diffusion-controlled PSM strategy utilizing size mismatch between pores and reactants has been developed to target selective functionalization and fine-tuning of material performance. Demonstrating through narrow-pore ZIF-90 reacting with amines of contrasting aliphatic chain lengths, we manage to regulate the extent and distribution of hydrophobic functionalization, and to judiciously tune the hydrophobicity of the crystalline materials. A subtle balance between reagent dose, water tolerance enhancement, and maintenance of gas adsorption performance has been achieved. ZIF-90 crystallites are imparted with surface hydrophobicity by only 1% aliphatic modification of ligands, while its hydrothermal stability is enhanced by 5% aliphatic modification, owing to the coverage of the vulnerable mesopore regions in the overall structure. Moreover, such low-dose PSM avoids severe pore blockage which would result in significant repellence of gas/vapor adsorbates (e.g. N2, CO2, H2O), as also predicted by ideal adsorbed solution theory (IAST), showing largely unaffected CO2/N2 and CO2/CH4 separation performance. This proposed spatially-differentiated strategy provides a facile route to implementing diffusion-limited PSM processes to fabricate core–shell-like MOFs.

Transforming growth factor type 1 receptor (ALK5) is kinase associated with a wide variety of pathological processes, and inhibition of ALK5 is a good strategy to treat many kinds of cancer and fibrotic diseases. Recently, a series of compounds have been synthesized as ALK5 inhibitors. However, the study of their selectivity against other potential targets remains elusive. In this research, a data-set of ALK5 inhibitors were collected and studied based on the combination of 2D-QSAR, molecular docking and molecular dynamics simulation. The quality of QSAR models were assessed statistically by F, R