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Phase transformation from Eu-dfdmt-RB to Eu-dfdmt-B was rationalized as a dissolution–reprecipitation process with dfdmt-INT isolated as the key intermediate.

A MOF colorimetric sensor for rapid and visual readout of trace acetylene in various matrices was developed by designing a UiO-type crystal and postsynthetically installing Pt(ii), which is based on Pt-driven acetylene polymerization.

Two primitive metal-organic frameworks (MOFs), NiL1 and NiL2, based on Ni8O6-cluster and ditopic pyrazolate linkers, L1 (with rigid alkyne arms) and L2 (with flexible alkyne chains), were prepared. The proton conductivities of these MOFs in pristine form and imidazole-encapsulated forms, Im@NiL1 and Im@NiL2, were measured and compared. Upon introduction of imidazole molecules, the proton conductivity could be increased by 3 to 5 orders of magnitude and reached as high as 1.72 × 10−2 S/cm (at 98% RH and 80 °C). Also, whether imidazole molecules were introduced or not, Ni8O6-MOFs with L2 in general gave better proton conductivity than those with L1 signifying that flexible side arms indeed assist proton conduction probably via establishment of efficient proton-conducting channels along with formation of highly ordered domains of water/imidazole molecules within the network cavities. Beyond the active Ni8O6-cluster, tuning flexibility of linker pendants serves as an alternative approach to regulate/modulate the proton conductivity of MOFs.

An acid- and base-stable halide coordination polymer exhibits excitation-dependent dual self-trapped exciton emissions and colorimetric and turn-off sensing on Hg2+ ions.

A semiconducting metal–organic crystalline nanotube array (MO-CNA) was constructed by the induction of Pb⋯S secondary interactions, exhibiting highly selective and sensitive NO2 sensing with a low limit of detection.

A tripodal linker with six pendant methylthio (–SCH3) groups was crystallized with Zn(II) ions to provide metal–organic framework (MOF) crystals, namely NOTT-6SMe-Zn, bearing three types of cage-like pores. NOTT-6SMe-Zn gives a highly distinguished color (dark brown) upon the introduction of Ag(I) ions, while it is insensitive towards other noble and transition metal ions. It exhibits a distinctly improved colorimetric detection of Ag(I) ions (e.g. as low as 30 ppm) and stability than that of non-methylthio functionalized NOTT-Zn. Better sensitivity is ascribed to the facile combination of soft sulfur atom and Ag(I) ions.

Automated detection of eye diseases using artificial intelligence techniques on optical coherence tomography (OCT) images is widely researched in the field of ophthalmology. Such detections are usually performed with the aid of computers. Using high-level simulations, this study investigates and evaluates three automated age-related macular degeneration (AMD) detection flows in terms of computation time and detection accuracy for future hardware-accelerated designs of intelligent and portable OCT systems. In this study, a block-matching and 3-Dimension filter (BM3DF), a hybrid median filter (HMF), and an adaptive wiener filter (AWF) are used to denoise the OCT images. Support vector machine (SVM), AlexNet, GoogLeNet, and Inception-ResNet are employed for AMD detection. Moreover, Local binary patterns, linear configuration patterns, and transfer learning techniques are used to extract image features. Simulation results reveal that machine-learning-based automated AMD detection realizes a high detection accuracy of 95.91% accompanied by low computation time when using the HMF rather than the BM3DF. When considering deep-learning-based automated AMD detection, the combination of HMF and Inception-ResNet achieves the highest detection accuracy of 98.64% but is accompanied by a dramatic increase in computation time. However, only AlexNet achieves a detection accuracy of 96.40%, accompanied by low computation time. In this study, the tradeoffs between the computation time and detection accuracy have been revealed by comparing the denoising methods for the distinct automated AMD detections.

The cruciform linker molecule here features two designer functions: the pyrazole donors for framework construction, and the vicinal alkynyl units for benzannulation to form nanographene units into the Ni8-pyrazolate scaffold. Unlike the full 12 connections of the Ni8(OH)4(H2O)2 clusters in other Ni8-pyrazolate networks, significant linker deficiency was observed here, leaving about half of the Ni(II) sites capped by acetate ligands, which can be potentially removed to open the metal sites for reactivity. The crystalline Ni8-pyrazolate scaffold also retains the crystalline order even after thermal treatments (up to 300 °C) that served to partially graphitize the neighboring alkyne units. The resultant nanographene components enhance the electroactive properties of the porous hosts, achieving hydrogen evolution reaction (HER) activity that rivals that of topical nickel/palladium-enabled materials.

A novel Zn(II) metal-organic framework [Zn4O(C30H12F4O4S8)3]n, namely ZnBPD-4F4TS, has been constructed from a fluoro- and thiophenethio-functionalized ligand 2,2′,5,5′-tetrafluoro-3,3′,6,6′-tetrakis(2-thiophenethio)-4,4′-biphenyl dicarboxylic acid (H2BPD-4F4TS). ZnBPD-4F4TS shows a broad green emission around 520 nm in solid state luminescence, with a Commission International De L’Eclairage (CIE) coordinate at x = 0.264, y = 0.403. Since d10-configured Zn(II) is electrochemically inert, its photoluminescence is likely ascribed to ligand-based luminescence which originates from the well-conjugated system of phenyl and thiophenethio moieties. Its luminescent intensities diminish to different extents when exposed to various metal ions, indicating its potential as an optical sensor for detecting metal ion species. Furthermore, ZnBPD-4F4TS and its NH4Br-loaded composite, NH4Br@ZnBPD-4F4TS, were used for proton conduction measurements in different relative humidity (RH) levels and temperatures. Original ZnBPD-4F4TS shows a low proton conductivity of 9.47 × 10−10 S cm−1 while NH4Br@ZnBPD-4F4TS shows a more than 25,000-fold enhanced value of 2.38 × 10−5 S cm−1 at 40 °C and 90% RH. Both of the proton transport processes in ZnBPD-4F4TS and NH4Br@ZnBPD-4F4TS belong to the Grotthuss mechanism with Ea = 0.40 and 0.32 eV, respectively.

Two chiral coordination polymers [Cu I (TMBP)(CH 3 CN) 2 ·ClO 4 ] n ( 1 ) and [Zn II (TMBP)(SCN) 2 ] n ( 2 ) have been synthesized with 3,3’,5,5’-tetramethyl-4,4’-bipyrazole (TMBP) as ligand. Their structures were determined by single-crystal X-ray diffraction (SCXRD) analysis and further characterized by power X-ray diffraction (PXRD) analysis, FT-IR spectroscopy, and thermogravimetric (TG) analysis. 1 is constructed by left-handed double-stranded helices with the same chirality, while 2 possesses right-handed single-helical chains. The existence of ClO 4 − in 1 might be the main reason for forming double-stranded helices, while it leads to single-helical chains under induction of SCN − , exhibiting a anion-directed synthesis process. The selected two single crystals are both homochiral according to the Flack parameters (≈0) from crystal refinement. The bulk sample of 1 exhibits a negative solid-state Cotton effect, while that of 2 shows a positive one. In addition, the crystal sample of 1 exhibits strong ligand-based and metal to ligand charge transition (MLCT) emission in solid-state luminescence with comparison to weakly luminous 2 at room temperature.

Two anion-directed Cu(I) coordination polymers (CPs), namely, [Cu2(TMBP)2(μ-CN)(I)·3.5H2O]n (1, TMBP = 3,3′,5,5′-tetramethyl-4,4′-bipyrazole) and [Cu2(TMBP)2(μ-SCN)(μ-CN)]n (2), were synthesized through solvothermal method and characterized by single crystal and powder X-ray diffraction, elemental analysis. 1 is a 3-dimension framework with nanocavity and (42 · 63 · 8) topology while 2 is a 2-dimension network with 3-fold penetration and (62 · 10)(6.6) topology, the difference in structure being related to the anions (I− or SCN−) included in precursor solution. Furthermore, 1 exhibits strong blue emission when excited at 315 nm, which should be resulted from I to Cu(I) charge transfer; however, no obvious luminescence was observed in case of 2. This work emphasizes a strategy of anion-directed synthesis of CPs for tuning photoluminescent property.

Solvothermal reaction between CuI and 5-(3-pyridyl)tetrazole (HPTA) in CH3CN and NH3·H2O/n-BuOH, afforded two kinds of Cu7I4 cluster-based coordination polymers 1 and 2, respectively. 1 is a racemic conglomerate of enantiomers crystallizing in the P6322 space group and 2 is a mesomer crystallizing in the Pc1 group. Both 1 and 2 show dual-channel emissions in which low-energy emission originates from a cluster-centered (CC) excited state while high-energy emission is attributed to an iodide-to-ligand charge transfer (XLCT)/metal-to-ligand charge transfer (MLCT) excited state. Of particular interest, 2 exhibits thermochromic luminescence originating from the combined effects of non-radiative transition and thermal deactivation of the XLCT excited state.

A linker molecule with four pendant thiophene functions was crystallized with Zr(IV) ions to form a semiconductive porous coordination solid (1.1 × 10−5 S cm−1). Oxidative treatment with FeCl3 guests then coupled the thiophene units to form conjugated bridges as covalent crosslinks. The resulting hybrid of a metal–organic framework and conjugated polymer featured robust crystalline order that withstood long-term air exposure and broad pH (from 0 to 12) conditions. Moreover, the homocoupled thiophene units, conjugated through sulfide links (–S–) with the linker backbone, afforded higher electronic conductivity (e.g., >2.2 × 10−3 S cm−1), which is characteristic of conductive polymer prototypes of polythiophene and polyphenylene sulfide. The crosslinked solid also exhibited proton conductivity that could be increased broadly upon H2SO4 treatment (e.g., from 5.0 × 10−7 to 1.6 × 10−3 S cm−1).

The cruciform linker molecule here features two designer functions: the pyrazole donors for framework construction, and the vicinal alkynyl units for benzannulation to form nanographene units into the Ni

The cruciform linker molecule here features two designer functions: the pyrazole donors for framework construction, and the vicinal alkynyl units for benzannulation to form nanographene units into the Ni8-pyrazolate scaffold. Unlike the full 12 connections of the Ni8(OH)4(H2O)2 clusters in other Ni8-pyrazolate networks, significant linker deficiency was observed here, leaving about half of the Ni(II) sites capped by acetate ligands, which can be potentially removed to open the metal sites for reactivity. The crystalline Ni8-pyrazolate scaffold also retains the crystalline order even after thermal treatments (up to 300 °C) that served to partially graphitizes the neighboring alkyne units. The resultant nanographene components enhance the electroactive properties of the porous hosts, achieving hydrogen evolution reaction (HER) activity that rivals topical nickel/palladium-enabled materials.

Comparison of different anticoagulants in blood management and complications with tranexamic acid (TXA) in total hip arthroplasty (THA) is unclear. Our aim was to compare the efficacy and safety among receiving nadroparin calcium, enoxaparin sodium or rivaroxaban after TXA in THA. 150 patients undergoing primary unilateral THA were received 15 mg/kg intravenous TXA (IV-TXA) before skin incision, followed by 1 of nadroparin calcium (Group A), enoxaparin sodium (Group B), or rivaroxaban (Group C) randomly during hospitalization. The primary outcome was hidden blood loss (HBL). Other outcomes such as the maximum hemoglobin (Hb) drop, total blood loss (TBL), the volume of drainage, transfusion rate, length of hospital stay (LOS), and complications were also compared. There were no statistically significant differences in HBL, the maximum hemoglobin (Hb) drop, transfusion rate, and complications among 3 groups. LOS was significantly higher for patients in Group B than Group A (P = .026). Neither deep venous thrombosis (DVT) nor pulmonary embolism (PE) occurred in any group. There were no differences in efficacy and safety in patients undergoing THA receiving nadroparin calcium, enoxaparin sodium, or rivaroxaban after anti-fibrinolysis with TXA.

The series of highly stable porous solids here feature systematic, regiospecific sulfur substitutions on the organic linkers for versatile functions. One major surprise lies in the controllable sequential reactions between sodium thiomethoxide (NaSMe) and octafluorobiphenyl-4,4'-dicarboxylic acid (H

The black, small-bandgap semiconducting framework Eu-dfdmat features extensive Eu3+–sulfur bridges from the linear linker 2,5-difluoro-3,6-dimercaptoterephthalate (dfdmt). Each Eu center is chelated to four dfdmt linkers to form an anionic coordination sphere involving four carboxyl O and four mercapto S centers (EuO4S4), wherein the charge buildup can be alleviated by the electron-withdrawing fluoro groups. The extensive metal-linker bonding, together with a trace of Eu2+ species, appears to boost electronic interaction in the 2D net, generating a small band gap of 1.31 eV (946 nm), albeit a modest conductivity (e.g., 10−6 S m−1). The crystals also exhibit persistent EPR signals indicative of organic radicals (g = 2.002). The Eu-dfdmt solid are stable in air and can be exfoliated into ultrathin nanosheets (ca. 5 nm; 6–8 layers).

A Co-MOF, [Co3(HL)2·4DMF·4H2O] was simply synthesized through a one-pot solvothermal method. With the semiconductor nature, its band gap was determined to be 2.95 eV by the Kubelka–Munk method. It is the first trinuclear Co-MOF employed for photocatalytic hydrogen evolution and CO2 reduction with cobalt–oxygen clusters as catalytic nodes. Hydrogen evolution experiments indicated the activity was related to the photosensitizer, TEOA, solvents, and size of catalyst. After optimization, the best activity of H2 production was 1102 μmol/(g h) when catalyst was ground and then soaked in photosensitizer solution before photoreaction. To display the integrated design of Co-MOF, we used no additional photosensitizer and cocatalyst in the CO2 reduction system. When −NH2 was used for light absorption and a Co–O cluster was used as catalyst, Co-MOF exhibited an activity of 456.0 μmol/(g h). The photocatalytic mechanisms for hydrogen evolution and CO2 reduction were also proposed.

A facilely available zwitterionic ligand, 1,1′-(1,4-phenylenebis(methylene))dipyridin-4(1H)-one (PBPO), has been designed to bear intraligand charge transfer (ILCT) energy states. PBPO was used to assemble two series of Ln(III) complexes with either 2D (6,3)-hcb network (LIFM-24(Ln), Ln = Pr, Nd, and Sm), or 1D loop-and-chain (LIFM-25(Ln), Ln = Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb) polymeric structures, as determined by the radius of the lanthanide ions. Highly efficient photoluminescence (PL) in the visible to near-infrared (NIR) regions can be obtained in these Ln-complexes, due to the extended energy transfer from both the triplet and ILCT states of the zwitterionic ligand. Among these complexes, LIFM-24(Pr) and LIFM-25(Dy) display excitation-dependent color tunable luminescence and white-light emission based on the combination of ligand-centered (LC) and metallic-centered (MC) emissions. Uniquely, a strict linear relationship was established between the excitation wavelength and the emission CIE (Commission Internationale de L'Eclairage) coordinates in a wide color range (orange to blue for LIFM-24(Pr), and yellow to blue for LIFM-25(Dy)), thereby providing prototype models for programmable PL color tuning and white-light emission, which are rarely achievable in homometallic Ln-complexes.

Electron-deficient Ru/Rh half-sandwich units are optoelectronical, stereochemical, and redox and catalytically active in nature. Four different species of these units were designed and successfully incorporated into UiO-67 frameworks by post-synthetic exchange (PSE) method and employed for photocatalytic H2 evolution and CO2 reduction. Among them, the PSE-MOF catalysts containing [M–OH2] (M = Rh or Ru) groups show higher photocatalytic activity than those with [M–Cl], providing a new example of the exploitation of H2O molecules as small ancillary ligands for the construction of Ru/Rh half-sandwich units and subsequent incorporation into MOFs as photocatalytic centers. The application of TEOA (triethanolamine) and DMA (N,N-dimethylaniline) as sacrificial agents leads to different catalytic mechanisms and durations. A long-term hydrogen evolution lasting for 174 h without significant decrease in efficiency was achieved in the RhOH2@UiO-DMA system, showing the advantage of PSE-MOFs as highly stable photocatalytic platforms with superior self-protective properties.

A novel metal-organic framework [CuCN(TMBP)·H2O]n (TCuCN) has been synthesized by the reaction of 3,3′,5,5′-tetramethyl-4,4′-bipyrazole (TMBP) and CuCN. Its structure was determined by single-crystal X-ray diffraction (SCXRD) analysis and further characterized by power X-ray diffraction (PXRD) analysis, FT-IR spectroscopy and thermogravimetric (TG) analysis. Previously reported structurally analogous TCuCl, TCuBr, TCuI have also been synthesized for Br2 adsorption comparison. All of these four MOFs exhibited reversible uptake of Br2 vapor judging by the unchanged PXRD patterns. Among four MOFs, Br2-loaded TCuI showed the most uptake amount of Br2 (15.7 ​wt%), providing the formula to be TCuI·0.33Br2. The different uptake amount of Br2 for TCuX (X ​= ​CN, Cl, Br, I) should be mainly ascribed to the intermolecular interaction between CuX and Br2.

A Zn(Ⅱ)-based metal–organic framework, namely MeOBim-Zn (1), has been prepared by the reaction between 5,6-dimethoxy-1H-benzo[d]imidazole (MeOBimH) and Zn(NO3)2 in the presence of aqueous ammonia through solvothermal method and characterized by single-crystal X-ray diffraction, TGA and FT-IR. 1 exhibits a (10,3)-a chiral network constructing from achiral MeOBim− linker and Zn(II) ions via spontaneous resolution. In addition, 1 shows photoluminescent emission at 433 nm upon photoexcitation at 365 nm and this emission may originate from dissipation of metal-perturbed π(MeOBim−) to π*(MeOBim−) intraligand (IL) excited state.

Four butterfly-like binuclear Ru(II)–Ru(II) and Ir(III)–Ru(II) complexes were designed and synthesized via a stepwise method by Ru(II)/Ir(III) metalloligands containing polypyridine (bpy)/phenylpyridine (ppy), phenanthroline (phen) and bibenzimidazole (BiBzIm) moieties. The absorption and photoluminescence of Ru(II)–Ru(II) compounds are dominated by metal-to-ligand charge-transfer (MLCT) transitions from Ru(II) centers to the organic ligand parts, which emit in the deep red region with a wavelength ∼700 nm. While in Ir(III)–Ru(II) complexes, an additional decay channel is opened for the energy transfer from the higher energy level MLCT state of Ir(III)-coordinated units to the lower-energy level MLCT state of Ru(II)-coordinated units, as approved by both experimental and theoretical DFT calculations. Therefore, similar deep red emission profiles originating from Ru(II) units are observed in Ir(III)–Ru(II) systems. These binuclear complexes were further tested as photosensitizers (PSs) to produce H2 in photocatalytic water reduction systems. The highest H2 production efficiency can be obtained in the heteronuclear IrRu(1) system after 80 hours continuous production with a TON value of 1088 based on the amount of IrRu(1) as PS, much higher than the other binunclear complexes and mononuclear counterparts. The results provide a new insight into the designing guidelines for noble metal complexes as emitting centers and photosensitizers in lighting/display materials and devices, as well as photocatalytic water splitting systems.

Photo-induced carbon dioxide conversion presents one of the basic reactions of natural photo-syntheses in green plants, which has inspired researchers to develop artificial materials and devices for efficient CO 2 photo-reduction into useful products and chemical fuels via light-driven photochemical reactions. This review article focuses on recent advances in visible-light-driven CO 2 photo-catalytic reduction studies based on Ru(II) and Ir(III) coordination complexes.

A new Eu-MOF was designed from an amino-functionalized ligand and Eu(iii) ions under solvothermal conditions. It is a highly porous, water-stable, and luminescent material, exhibiting pH sensing in the acidic range of pH = 7-3 with selective detection for Cd

A Pb(II)-based coordination polymer, namely Pb-BSDC, has been synthesized by the reaction of 2,2′-bis(sulfomethyl)-[1,1′-biphenyl]-4,4′-dicarboxylic acid (H4BSDC) and lead nitrate through solvothermal self-assembly strategy. With the protophilic sulfonic groups and hydrogen-bonding interactions, Pb-BSDC exhibits efficient water-assisted proton conduction. Importantly, single-crystal Pb-BSDC shows a high proton conductivity of 1.71 ​× ​10-2 ​S ​m-1 at 90 ​°C and 85% RH (relative humidity), suggesting a promising candidate for proton-conductor. Further mechanism investigation indicates that proton conduction in bulk sample of Pb-BSDC follows the Vehicle mechanism (Ea ​= ​0.63 ​eV) while single-crystal state follows the Grotthuss mechanism (Ea ​= ​0.35 ​eV). In addition, the luminescent property of Pb-BSDC was also studied and it showed a broad band emission with the maximum at 502 ​nm under the irradiation of 310 ​nm UV light.

A porous Zr(IV)-based metal-organic framework, namely Zr-TNDC, has been prepared by the reaction of zirconium salt and 1,5-bis(methylthio)naphthalene-2,6-dicarboxylic acid through solvothermal method. The existent methylthio groups provide a platform for post-synthetic modification, therefore oxidized Zr-TNDC-Ox and further acidified H@Zr-TNDC-Ox were successfully prepared. Electrochemical impedance spectroscopy was performed to evaluate the proton conductivity of synthesized materials. Importantly, H@Zr-TNDC-Ox exhibited a highly improved proton conductivity of 3.16 ​× ​10−2 ​S ​m−1 at 90 ​°C and 95% RH in comparison to the pristine Zr-TNDC (7.88 ​× ​10−5 ​S ​m−1). Proton conductivities at different relative humidity and temperatures were also measured and Arrhenius equation was used to investigate the proton conduction process. It indicated that all of the synthesized framework materials correspond to Grotthuss mechanism.

The development of efficient and economical catalysts for photocatalytic water splitting and hydrogen production is one of the promising methods to alleviate the current energy crisis. In this work, we synthesized a novel Co-O cluster based coordination polymer, [Co2(HL)2·(DMF)2·H2O]·solvents (Co-CP) by a facile solvothermal method from amino-functionalized ligand and non-precious cobalt salt. The Co-CP possesses a bandgap of 2.65 eV, whose conduction and valence band are -0.8 and 1.85 eV, respectively. Efficiently, the visible-light driven photocatalytic hydrogen evolution rate of Co-CP reaches 1778 μmol g−1 h−1, due to the rapid charge transfer and efficient suppression of electron-hole recombination as determined by photocurrent response and photoluminescence measurement. Possible photocatalytic mechanisms are proposed, for which the Co-O clusters are predicted to be the active sites.

A Co-MOF, [Co

Metal-organic complexes assembled from coordinative interactions are known to be able to display a wide range of photoluminescent behaviors benefiting from an extensive number of metal ions, organic linkers, and inclusion guests, depending on the multifaceted nature of their chemical structures and photophysical properties. In the past two decades, the white-light-emitting (WLE) and photoluminescent color-tuning (PLCT) materials based on the single-phase metal-organic coordination assemblies have merited particular attention and gained substantial advances. In this review, we give an overview of recent progress in this field, placing emphasis on the WLE and PLCT properties realized in the single-phase materials, which covers the origin, generation, and manipulation of different types of photoluminescence (PL) derived from ligand-centered (LC), metal/cluster-centered (MC or CC), excimer/exciplex-based (EX), metal-to-ligand or ligand-to-metal charge-transfer-based (MLCT or LMCT), or guest-included emissions. The coordination assemblies in this topic can be generally classified into three categories [(1) mono/homometallic coordination assemblies based on main group (s,p-block), transition (d-block), or lanthanide (f-block) metal centers, (2) s/p-f-, d-f-, or f-f-type heterometallic coordination assemblies, and (3) guest-included coordination assemblies] for which WLE and PLCT properties can be achieved by virtue of either a wide-band/overlapped emission covering the whole visible spectrum from a single emitting center or a combination of complementary color emissions from multiple emitting centers/origins. Some state-of-the-art assembly methods and successful design models relevant to the above three categories are elaborated to demonstrate how to achieve efficient and controllable white-light emission in a single-phase material through a tunable PL approach. Potential applications in the fields of lighting and displaying, sensing and detecting, and barcoding and patterning are surveyed, and at the end, possible prospects and challenges for future development along this line are proposed.

Two-dimensional (2D) metal–organic frameworks have exhibited a range of fascinating attributes, of interest to numerous fields. Here, a calcium-based metal-organic framework with a 2D layered structure has been designed. Dual emissions relating to intralayer excimers and interlayer trapped excitons are produced, showing excitation-dependent shifting tendency, characteristic of a low dimensional semiconductor nature. Furthermore, the layer stacking by weak van der Waals forces among dynamically coordinated DMF molecules enables exfoliation and morphology transformation, which can be achieved by ultrasound in different ratios of DMF/H2O solvents, or grinding under appropriate humidity conditions, leading to nano samples including ultrathin nanosheets with single or few coordination layers. The cutting down of layer numbers engenders suppression of interlayer exciton-related emission, resulting in modulation of the overall emitting color and optical memory states. This provides a rare prototypical model with switchable dual-channel emissions based on 2D-MOFs, in which the interlayer excitation channel can be reversibly tuned on/off by top-down exfoliation and morphology transformation.

The combination of PHC pile (prestressed concrete pile) with geogrid to reinforce the foundation has been widely used in high-speed railway, and the response of dynamic stress under the high-speed train is worth studying. By using Midas/GTS NX software to establish a 3-D model of pile-net composite foundation in one section of Hangzhou - Shenzhen line, the influence of pile-net composite foundation generated by high-speed train is studied. Moreover, this paper also studies the distribution and propagation of dynamic stress generated by train load in soft soil area. The results show that the dynamic stress reducing quickly in the embankment structure and the time –history curve of the dynamic stress behaves differently along the depth. With the depth increasing, there is phenomenon of peak superposition in the time-history curve of the vertical dynamic stress. In the meanwhile, the PHC pile is the main structure to propagate and sustain the dynamic stress in soft soil area, and with the tendency of ‘large in the middle, small on both ends’.