Metal-Organic Framework Featuring Cubic Caged Structures for One-Step Ethylene Purification from Ethylene/Ethane Mixtures.

Separation of C2H6/C2H4 mixtures is of significant importance in the chemical industry but remains a challenge due to the physicochemical similarities of C2H6 and C2H4. Herein, a metal-organic framework (MOF), [Zn4(µ4-O)(PCTF)3]n (Zn-PCTF) (PCTF2-= 5-trifluoromethyl-1H-pyrazole-4-carboxylic), is provided for the removal of C2H6 from C2H6/C2H4 mixtures. Zn-PCTF displays a three-dimensional framework featuring one-dimensional pore channels with periodic bottleneck segments. The well-balanced C2H6 adsorption capacity (79.0 cm3 g-1 at 298 K) and C2H6/C2H4 selectivity (1.8) for Zn-PCTF under ambient conditions boost Zn-PCTF with highly promising potentials for efficient purification of C2H4 from C2H6/C2H4 mixtures, which is verified by the dynamic column breakthrough experiments. The well-matched caged pores and suitable pore chemistry (particularly the presence of abundant Lewis base sites (N, O, and F) on the pore surfaces) for C2H6 account for the high-performance C2H6/C2H4 separation of Zn-PCTF unveiled by computational simulations.

Metal-Organic Frameworks Possessing Suitable Pores for Xe/Kr Separation.

Adsorption separation of the Xe/Kr mixture remains a tough issue since Xe and Kr have an inert nature and similar sizes. Here we present a chlorinated metal-organic framework (MOF) [JXNU-19(Cl)] and its nonchlorinated analogue (JXNU-19) for Xe/Kr separation. The two isostructural MOFs constructed from the heptanuclear cobalt-hydroxyl clusters bridged by organic ligands are three-dimensional structures. Detailed contrast of the Xe/Kr adsorption separation properties of the MOF shows that significantly enhanced Xe uptakes and Xe/Kr adsorption selectivity (17.1) are observed for JXNU-19 as compared to JXNU-19(Cl). The main binding sites for Xe in the MOF revealed by computational simulations are far away from the chlorine sites, suggesting that the introduction of the chlorine groups results in the unfavorable Xe adsorption for JXNU-19(Cl). The optimal pores, high surface area, and multiple strong Xe-framework interactions facilitate the effective Xe/Kr separation for JXNU-19.

Advances in the mechanisms and applications of RNA silencing in crop protection.

RNA silencing (or RNA interference, RNAi) is a conserved mechanism for regulating gene expression in eukaryotes, which plays vital roles in plant development and response to biotic and abiotic stresses. The discovery of trans-kingdom RNAi and interspecies RNAi provides a theoretical basis for exploiting RNAi-based crop protection strategies. Here, we summarize the canonical RNAi mechanisms in plants and review representative studies associated with plant-pathogen interactions. Meanwhile, we also elaborate upon the principles of host-induced gene silencing, spray-induced gene silencing and microbe-induced gene silencing, and discuss their applications in crop protection, thereby providing help to establish novel RNAi-based crop protection strategies.

Boosting the C2H2/CO2 Separation Performance of Metal-Organic Frameworks through Fluorine Substitution.

A pair of metal-organic frameworks (MOFs) of JXNU-15 (formulated as [Co6(µ3-OH)6(BTB)2(BPY)3]n, BTB3- = benzene-1,3,5-tribenzoate and BPY = 4,4'-bipyridine) and its fluorinated JXNU-15(F) ([Co6(µ3-OH)6(SFBTB)2(BPY)3]n) based on the fluorous 1,3,5-tri(3,5-bifluoro-4-carboxyphenyl)benzene (SFBTB3-) ligands were presented. The detailed comparisons of the acetylene/carbon dioxide (C2H2/CO2) separation abilities between the isostructural JXNU-15(F) and JXNU-15 were presented. In comparison with the parent JXNU-15, the higher C2H2 uptake, larger adsorption selectivity of the C2H2/CO2 (50/50) mixture, and enhanced C2H2/CO2 separation performance endow JXNU-15(F) with highly efficient C2H2/CO2 separation performance, which is demonstrated by singe-component gas adsorptions and dynamic gas mixture breakthrough experiments. The fluorine substituents exert the crucial effects on the enhanced C2H2/CO2 separation ability of JXNU-15(F) and play the dominant role in the C2H2-framework interactions, as uncovered by computational simulations. This work illustrates a powerful fluorine substitution strategy for boosting C2H2/CO2 separation ability for MOFs.

Cucurbituril-Shaped Cd18(triazolate)12 Unit-Based Metal-Organic Framework Exhibiting an C2H2/CO2 Separation Ability.

Herein, a metal-organic framework (MOF), {[(Me2NH2)4][Cd(H2O)6][Cd18(TrZ)12(TPD)15(DMF)6]}n (denoted as JXNU-18, TrZ = triazolate), constructed from the unique cucurbituril-shaped Cd18(TrZ)12 secondary building units bridged by 2,5-thiophenedicarboxylic (TPD2-) ligands, is presented. The formation of the cucurbituril-shaped Cd18(TrZ)12 unit is unprecedented, demonstrating the geometric compatibility of the organic linkers and the coordination configurations of the cadmium atoms. Each Cd18(TrZ)12 unit is connected to eight neighboring Cd18(TrZ)12 units through 30 TPD2- linkers, affording the three-dimensional structure of JXNU-18. More interesting is that JXNU-18 displays an efficient C2H2/CO2 separation ability, as revealed by the gas adsorption experiments and dynamic gas breakthrough experiments, which afford insights into the potential applications of JXNU-18 in gas separation. The tubular pores composed of two Cd18(TrZ)12 units bridged by six 2,5-thiophenedicarboxylic linkers provide the suitable pore space for C2H2 trapping, as unveiled by computational simulations.

Enhancement of Propadiene/Propylene Separation Performance of Metal-Organic Frameworks by an Amine-Functionalized Strategy.

Here, a hexanuclear Co6(µ3-OH)6 cluster-based metal-organic framework (MOF), [Co6(µ3-OH)6(BTB)2(bpy)3]n (JXNU-15) (bpy = 4,4'-bipyridine), with the 1,3,5-tri(4-carboxyphenyl)benzene (BTB3-) ligand was synthesized for the challenging propadiene/propylene separation. The combination of a large pore volume and a suitable pore environment boosts the significantly high propadiene (C3H4) uptake (311 cm3 g-1 at 298 K and 100 kPa) for JXNU-15. An amine-functionalized MOF of JXNU-15(NH2) was further obtained with the 1,3,5-tri(4-carboxyphenyl)benzene analogue of 3,3″-diamino-5'-(3-amino-4-carboxyphenyl)-[1,1':3',1″-terphenyl]-4,4″-dicarboxylic ligand. The comparative studies of propadiene/propylene(C3H4/C3H6) separation performance between isostructural JXNU-15 and JXNU-15(NH2) are provided. JXNU-15(NH2) exhibits an impressive C3H4 capacity at low pressures with 69.1 cm3 g-1 at 10 kPa, which is twice that of JXNU-15 under the same conditions. Moreover, the separation selectivity of JXNU-15(NH2) is 1.3-fold higher as compared to JXNU-15. JXNU-15(NH2) with enhanced C3H4/C3H6 separation performance was elegantly illustrated by gas separation experiments and theoretical simulations. This work presents an amine-functionalized strategy for the enhancement of the C3H4/C3H6 separation performance of MOF.

Dinuclear Nickel-Oxygen Cluster-Based Metal-Organic Frameworks with Octahedral Cages for Efficient Xe/Kr Separation.

Xe/Kr separation is industrially important but remains a daunting issue in chemical separations. Herein, a fluorinated metal-organic framework (MOF), [Ni2(µ2-O)(TFBPDC)(tpt)2]n (named JXNU-13-F), built from 3,3',5,5'-tetrakis(fluoro)biphenyl-4,4'-dicarboxylic (TFBPDC2-) and 2,4,6-tri(4-pyridinyl)-1,3,5-triazine (tpt) ligands is provided. JXNU-13-F displays a three-dimensional (3D) framework constructed from distorted octahedral cages and an impressive Xe capacity of 144 cm3 g-1 at 273 K and 1 bar, ranking among top MOFs. The high Xe uptake and moderate Xe/Kr adsorption selectivity endow JXNU-13-F with efficient Xe/Kr separation demonstrated by experimental column breakthrough tests. The comparative studies of gas adsorption between isostructural JXNU-13-F and JXNU-13 (the nonfluorinated analogue ([Ni2(µ2-O)(BPDC))(tpt)2]n with biphenyl-4,4'-dicarboxylic (BPDC2-)) revealed that the F groups serve as the innocent groups during the Xe and Kr adsorption in JXNU-13-F. Thus, a combination of highly hydrophobic and π-electron-rich pore surfaces made of aromatic rings with strong interactions with the Xe atom possessing large polarizability and appropriate pore sizes that match well Xe having a large atom diameter has resulted in high Xe uptake and effective Xe/Kr separation characteristics of JXNU-13-F.

Structural Evolution from Noninterpenetrated to Interpenetrated Thorium-Organic Frameworks Exhibiting High Propyne Storage.

Two thorium-organic frameworks of [Th6O4(OH)4(TFBPDC)6(H2O)6]n (Th-TFBPDC) and [Th6O4(OH)4(TFBPDC)4(HCOO)4(H2O)6]n (Th-TFBPDC-i) constructed from the 3,3',5,5'-tetrakis(fluoro)biphenyl-4,4'-dicarboxylate (TFBPDC2-) ligand were obtained in a reaction. At an early stage of the reaction, the formation of the three-dimensional (3D) framework of Th-TFBPDC was discovered. At a later stage of the reaction, the complete product of Th-TFBPDC-i was obtained. The structural evolution from a noninterpenetrated network of Th-TFBPDC to a 2-fold interpenetrated network of Th-TFBPDC-i is a dissolution-recrystallization process and rationalized as the four equatorial TFBPDC2- ligands in an octahedral [Th6O4(OH)4(TFBPDC)12] unit were displaced by four formate ligands to form a [Th6O4(OH)4(TFBPDC)8(HCOO)4] unit via a ligand substitution reaction. The large pore volume as well as the strong interactions between the host framework and guest propyne (C3H4) molecules demonstrated by computational results endow the highly water-stable Th-TFBPDC with the best-performing C3H4 storage under ambient conditions. This work presents a rare example of structural evolution from a 3D noninterpenetrated network to a 2-fold 3D interpenetrated network and a highly promising metal-organic framework (MOF) for C3H4 storage with a C3H4 uptake of 8.16 mmol g-1 at 298 K.

Octanuclear Cobalt(II) Cluster-Based Metal-Organic Framework with Caged Structure Exhibiting the Selective Adsorption of Ethane over Ethylene.

A novel metal-organic framework (MOF) of [Co8(OH)4(TCA)4(H2O)4]n (abbreviation: JXNU-9) based on the unique octanuclear Co8(µ3-OH)4 clusters linked by 4,4',4″-nitrilotribenzoate (TCA3-) ligands featuring small caged structures and one-dimensional channels was prepared and characterized. JXNU-9 shows a high C2H6 uptake capacity of 3.60 mmol g-1 (4.46 mmol cm-3) at 298 K and 1 atm with a small isosteric heat of adsorption (23.6 kJ mol-1) and a moderate C2H6/C2H4 adsorption selectivity of 1.7, resulting in excellent C2H6/C2H4 separation performance. The pore walls decorated by plenty of aromatic rings provide π-electron-cloud-surrounding environments to accommodate the large polarizable C2H6 molecules. The calculations demonstrate that the rich π-systems in JXNU-9 facilitate an adsorption affinity for large C2H6 molecules through multiple C-H···π interactions. Additionally, the open metal sites located in the concave pores with a close Co···Co separation (4.21 Å) in octanuclear Co8(µ3-OH)4 clusters make the open metal sites inaccessible for the C2H4 molecule with a kinetic diameter of 4.163 Å. Thus, the annihilation of open metal sites in this structure is achieved, which further facilitates the C2H6-selective C2H6/C2H4 separation.

Metal-Organic Frameworks Featuring 18-Connected Nonanuclear Rare-Earth Oxygen Clusters and Cavities for Efficient C2H2/CO2 Separation.

Two rare-earth (RE) metal-organic frameworks (MOFs) formulated as {(Me2NH2)2[RE9(µ3-OH)8(µ2-OH)3(DCPB)6(H2O)3]}n (RE = Y3+ and Tb3+; termed JXNU-10) built from a triangular 3,5-di(4'-carboxylphenyl)benzoic acid (DCPB3-) ligand are presented. JXNU-10 features the rarely observed 18-connected nonanuclear [RE9(µ3-OH)8(µ2-OH)3] clusters, one-dimensional-nanosized tubular channels, and trigonal-bipyramidal cavities. The presence of the high-nuclear RE-oxo clusters and the robust coordination bonds between the highly charged RE ions and the hard base of the carboxylate/hydroxyl oxygen atoms yielded the water-resistant JXNU-10 materials. JXNU-10 exhibits highly selective sorption of C2H2 over CO2 and highly efficient separation of a C2H2 and CO2 mixture. The carboxylate oxygen atoms and the rich π systems of the organic ligands on the pore walls are the desirable binding sites for a C2H2 molecule with acidic hydrogen atoms and an alkyne group, facilitating the excellent efficiency of JXNU-10 for C2H2/CO2 separation demonstrated by breakthrough experiments.

Quercetin induces apoptosis and enhances gemcitabine therapeutic efficacy against gemcitabine-resistant cancer cells.

Quercetin, an abundant flavonoid found in various fruits and vegetables, displays multiple biological activities, including anticancer effects. Therefore, quercetin is receiving increasing attention as a potential adjuvant anticancer treatment. Gemcitabine (GEM) resistance is a major issue for clinicians and patients with advanced cancers, making it crucial to determine ways to bolster its effects. In this study, we explored the anticancer effects and mechanistic actions of quercetin in GEM-resistant cancer cells. Pancreatic cancer (BxPC-3, PANC-1) and hepatocellular carcinoma (HepG2, Huh-7) cell lines were studied. Proliferation assays showed that quercetin had cytotoxic effects on GEM-resistant cell lines (HepG2 and PANC-1), and flow cytometric analysis indicated a significant pro-apoptotic effect on these cell lines. GEM treatment, in combination with quercetin, resulted in increased anticancer effects compared with GEM alone. Quercetin led to S phase arrest in GEM-resistant cell lines, and western blot analysis revealed tumour protein p53 upregulation and cyclin D1 downregulation. This study provides mechanistic insight into the anticancer effects of quercetin and suggests that quercetin adjuvant treatment may benefit patients who are resistant to GEM therapy.

Proton-Conductive Coordination Polymers Based on Diphenylsulfone-3,3'-disulfo-4,4'-dicarboxylate with Well-Defined Hydrogen Bonding Networks.

The diphenylsulfone-3,3'-disulfo-4,4'-dicarboxylic acid (H4-DPSDSDC) ligand and its coordination polymers, [K2Zn(C14H6S3O12)(H2O)4]n (1) and {[Cu3(µ3-OH)2(C14H6S3O12)(H2O)3(DMF)]·3(H2O)}n (2) (C14H6S3O12 = diphenylsulfone-3,3'-disulfo-4,4'-dicarboxylate), were synthesized. The Zn(H2O)4 units in 1 are connected by DPSDSDC4- ligands to generate a one-dimensional (1D) chain, which is bridged by K-O bonds associated with bridging water molecules and sulfonate groups to yield a two-dimensional (2D) layer. In 2, the 1D hydroxyl-bridging Cu(II) chains are connected by DPSDSDC4- ligands to give a 2D layer. The 2D layers in 1 and 2 are further connected by interlayered hydrogen bonds to give three-dimensional (3D) frameworks. Compounds 1 and 2 have good conductivities of 1.57 × 10-4 and 5.32 × 10-5 S cm-1, respectively. Continuous well-defined hydrogen bonding networks associated with water molecules, sulfonate groups, and carboxylate groups were observed in compounds 1 and 2. Such hydrogen bonding networks provide hydrophilic domains and effective transfer pathways for protons. Here, we present elegant examples of a precise determination of the pathways for proton transport.

Rare Three-Dimensional Uranyl-Biphenyl-3,3'-disulfonyl-4,4'-dicarboxylate Frameworks: Crystal Structures, Proton Conductivity, and Luminescence.

Due to the intrinsic coordination preference of the linear uranyl unit, uranyl-organic frameworks (UOFs) are generally prone to exhibiting low-dimensional structures. Reactions of uranyl nitrate with biphenyl-3,3'-disulfonyl-4,4'-dicarboxylic acid dipotassium salt (K2H2BPDSDC) under different conditions led to three UOFs, namely, {(Me2NH2)[K2(UO2)3(µ3-O)(µ3-OH)2(µ2-OH)(BPDSDC)(H2O)3]·4DMF}n (1), {[K2(UO2)(µ3-O)(BPDSDC)0.5(H2O)2]}n (2), and {(Me2NH2)2.5[K1.5(UO2)(BPDSDC)1.5(H2O)3]}n (3). Compounds 1 and 2 contain one-dimensional (1D) ribbon structures formed from UO22+ units bridged by µ3-O atoms and carboxylate groups. The 1D ribbons in 1 are linked by K+ atoms to form a two-dimensional (2D) layer, which is further pillared by the biphenyl units to give a three-dimensional (3D) framework. For 2, the oxygen atoms of UO22+ units in each 1D ribbon bridge the K+ atoms to form four -[K-O-K]n- infinite chains located above and below the ribbon. The 1D ribbons in 2 are bridged by sulfonate groups to generate a 3D substructure featuring 1D channels occupied by biphenyl moieties. In 3, each mononuclear [(UO2)(COO)3] unit is bridged by three K+ atoms to form a 3D substructure featuring 1D small left-handed and large righted helical channels occluded by biphenyl moieties. Compound 2 exhibits an excellent proton conductivity with the highest conductivity of 1.07 × 10-3 S cm-1. The inner walls of 1D channels of 2 are full of the hydrophilic sulfonate groups, which boost enrichment of the guest water molecules, thus resulting in a high proton conductivity. Finally, temperature dependence of fluorescent studies showed that compounds 1 and 2 display the characteristic uranyl emissions. This work presents the elegant examples of the rarely explored 3D UOFs and expands the potentials of UOFs.

Lanthanide 5,7-Disulfonate-1,4-naphthalenedicarboxylate Frameworks Constructed from Trinuclear and Tetranuclear Lanthanide Carboxylate Clusters: Proton Conduction and Selective Fluorescent Sensing of Fe3.

The novel sulfonate-carboxylate ligand of 5,7-disulfonate-1,4-naphthalenedicarboxylic acid (H4-DSNPDC) was synthesized, and its series of lanthanide compounds {[Ln3(µ2-OH)(DSNPDC)2(H2O)x]·yH2O}n (JXNU-7; Ln = La3+, x = 10. y = 4; Ln = Nd3+, Sm3+ Eu3+, x = 9, y = 2) and {[Ln4(µ3-OH)4(DSNPDC)2(H2O)11]·28H2O}n (JXNU-8; Ln = Eu3+, Gd3+) are presented. JXNU-7 is a three-dimensional structure based on linear trinuclear Ln3 building units, while JXNU-8 has a two-dimensional layer constructed from tetranuclear Ln4(µ3-OH)4 building units. The representative Eu compounds of JXNU-7 and -8 show good proton conductive properties under high humidity. The hydrophilic sulfonate groups pointing to the pores and the water molecules included in the pores mainly contribute to the high proton conductivity for the materials. The presence of one-dimensional infinite hydrogen-bonded networks in channels of JXNU-7(Eu) facilitates a fast and efficient proton transfer, resulting in higher proton conductivity in comparison to that of JXNU-8(Eu). Additionally, JXNU-7(Eu) with a characteristic red emission exhibits a promising potential for selective sensing of Fe3+ ions in aqueous solution. Our work demonstrates the integration of functional organic components (sulfonate groups) and inorganic components (lanthanide centers) in MOFs for the successful preparation of multifunctional MOF materials.

Fluorinated Biphenyldicarboxylate-Based Metal-Organic Framework Exhibiting Efficient Propyne/Propylene Separation.

A novel fluorinated biphenyldicarboxylate ligand of 3,3',5,5'-tetrafluorobiphenyl-4,4'-dicarboxylic acid (H2-TFBPDC) and its terbium metal-organic framework, {[Tb2(TFBPDC)3(H2O)]·4.5DMF·0.5H2O}n (denoted as JXNU-6), were synthesized. JXNU-6 exhibits a three-dimensional (3D) framework built from one-dimensional (1D) terbium carboxylate helical chains bridged by TFBPDC2- linkers. The 3D framework of JXNU-6 features 1D fluorine-lined channels. The gas adsorption experiments show that the activated JXNU-6 (JXNU-6a) displays distinct adsorption behavior for propyne (C3H4) and propylene (C3H6) gases. The effective removal of a trace amount of C3H4 from C3H6 was achieved by JXNU-6a under ambient conditions, which is demonstrated by the column-breakthrough experiments. The modeling studies show that the preferential binding sites for C3H4 are the exposed F atoms on the pore surface in 1D channels. The strong C-H···F hydrogen bonds between C3H4 molecules and F atoms of TFBPDC2- ligands dominate the host-guest interactions, which mainly account for the excellent C3H4/C3H6 separation performance of JXNU-6a. This work provides a strategy for specific recognition toward C3H4 over C3H6 through the C-H···F hydrogen bond associated with the fluorinated organic ligand.

Water-Stable Europium 1,3,6,8-Tetrakis(4-carboxylphenyl)pyrene Framework for Efficient C2H2/CO2 Separation.

Compound {(Me2NH2)3[Eu7(µ3-O)2(TBAPy)5(H2O)6]·12.5DMF} n (JXNU-5), constructed from the 1,3,6,8-tetrakis(4-carboxylphenyl)pyrene (TBAPy4-) ligand and one-dimensional (1D) europium carboxylate rods, is presented. JXNU-5 has a three-dimensional framework with 1D channels. The strong coordination bonds between EuIII ions with high charge densities and carboxylate O atoms as well as strong π···π-stacking interactions between pyrenes lead to a water-resistant JXNU-5, which was verified by powder X-ray diffraction and surface area measurements. The breakthrough simulations and experiments demonstrate that an efficient C2H2/CO2 (50/50 mixture) gas separation at ambient conditions was achieved with JXNU-5. The calculation results show that the dominating interactions between the absorbed C2H2 molecules and host framework are hydrogen bonds associated with the carboxylate O atoms exposed on the pores. Thus, an elegant example of a water-stable metal-organic framework for effective C2H2/CO2 separation is demonstrated.

Efficient production of a recombinant Venerupis philippinarum defensin (VpDef) in Pichia pastoris and characterization of its antibacterial activity and stability.

VpDef is a novel defensin isolated from the clam Venerupis philippinarum. Previously it was expressed in Escherichia coli; however, the E. coli-derived recombinant VpDef did not show effective antimicrobial activity against Staphyloccocus aureus or the Gram-negative bacteria tested. As such, the goal of this study was to design, express, and purify a recombinant VpDef (rVpDef) in Pichia pastoris and to determine its antibacterial potency and stability. A 6.9 KDa rVpDef was successfully expressed as a secreted peptide in P. pastoris, and the amount of rVpDef accumulation was shown to reach as high as approximate 60 µg per 1 ml of culture medium only after an initial optimization was performed. The purified rVpDef demonstrated a broad antibacterial spectrum and was active against six typical common bacteria, both Gram-positive and Gram-negative. A minimal inhibition concentration of as low as 50 µg/ml was observed for rVpDef against the growth of E. coli O157 (ATCC 35150). Moreover, rVpDef was tolerant to temperature shock and proteinase digestion and maintained a high stability over a relatively broad pH range. In addition, rVpDef had a low hemolytic activity against rabbit erythrocytes. Taken together, this study demonstrated that rVpDef could be produced in a large-scale manner in P. pastoris and has a good antibacterial activity and suitable stability. This is the first report on heterologous expression of a biologically active VpDef in P. pastoris, supporting its use for both research and application purposes.

Lanthanide-benzophenone-3,3'-disulfonyl-4,4'-dicarboxylate Frameworks: Temperature and 1-Hydroxypyren Luminescence Sensing and Proton Conduction.

The benzophenone-3,3'-disulfonyl-4,4'-dicarboxylic acid (H4-BODSDC) ligand and compounds, {(H3O)[Ln(BODSDC)(H2O)2]} n (Ln = Tb(1), Eu(2), and Gd(3)), were synthesized and structurally characterized. The lanthanide centers are bridged by the carboxylate groups of BODSDC4- ligands to give a one-dimensional (1D) chain. The 1D chains are connected by the BODSDC4- ligands to yield a three-dimensional (3D) structure featuring 1D channels. The lanthanide ions are efficiently sensitized by the BODSDC4- ligand with an appropriate triplet excited state to generate characteristic Tb(III) and Eu(III) emissions in Tb(1) and Eu(2), respectively. Thus the binary compound, {(H3O)[Tb0.93Eu0.07(BODSDC)(H2O)2]} n (abbreviated as Tb0.93Eu0.07-BODSDC), was achieved for use as a ratiometric temperature sensor. The ratio values of Tb(III) emission at 544 nm ( ITb) and Eu(III) emission at 616 nm ( IEu) for Tb0.93Eu0.07-BODSDC linearly vary with temperature over a wide range, which indicates that the Tb0.93Eu0.07-BODSDC is a thermometer for ratiometric fluorescence sensing of temperature. Additionally, Tb(1) is a fluorescent probe for detecting 1-hydroxypyrene (1-HP) by luminescence quenching. The uncoordinated sulfonate oxygens exposed on the channel surfaces serve as the binding sites for 1-HP. Finally, the enrichment of the solvent water molecules in the channels decorated by high-density hydrophilic sulfonate groups resulted in a high proton conductivity for Tb(1).

Nickel-4'-(3,5-dicarboxyphenyl)-2,2',6',2″-terpyridine Framework: Efficient Separation of Ethylene from Acetylene/Ethylene Mixtures with a High Productivity.

A novel compound, [Ni(DCPTP)] n (termed Ni-DCPTP), based on the 4'-(3,5-dicarboxyphenyl)-2,2',6',2″-terpyridine (DCPTP2-) ligand was presented here. Ni-DCPTP has a three-dimensional structure with a ths topology featuring one-dimensional (1D) helical channels. Ni-DCPTP shows an efficient removal of a trace amount of C2H2 from a C2H2/C2H4 (1/99) mixture with an excellent C2H4 productivity as demonstrated by both the transient breakthrough simulations and breakthrough experiments, generating the polymer-grade C2H4 gas (C2H2 < 40 ppm). The carboxylate oxygen atoms on the surface of 1D channels are the preferential binding sites for C2H2 molecules. This work demonstrates an elegant example with carboxylate oxygen-functionalized pore channels for effective C2H2/C2H4 separation.

The Highly Connected MOFs Constructed from Nonanuclear and Trinuclear Lanthanide-Carboxylate Clusters: Selective Gas Adsorption and Luminescent pH Sensing.

The highly odd-numbered 15-connected nonanuclear [Ln9(µ3-O)2(µ3-OH)12(O2C-)12(HCO2)3] and 9-connected trinuclear [Ln3(µ3-O)(O2C-)6(HCO2)3] lanthanide-carboxylate clusters with triangular and linear carboxylate bridging ligands were synergistically combined into Ln-MOFs, [(CH3)2NH2]3{[Ln9(µ3-O)2(µ3-OH)12(H2O)6][Ln3(µ3-O)(H2O)3](HCO2)3(BTB)6}·(solvent)x (abbreviated as JXNU-3, Ln = Gd, Tb, Er; BTB3- = benzene-1,3,5-tris(4-benzoate)), displaying a (3,9,15)-connected topological net. The JXNU-3(Tb) exhibits highly selective CO2 adsorption capacity over CH4 that resulted from the high localized charge density induced by the presence of the nonanuclear and trinuclear cluster units. In addition, JXNU-3(Tb) with high chemical stability and characteristic bright green color exhibits fluorescent pH sensing, which is pertinent to the different protonation levels of the carboxylate groups of the benzene-1,3,5-tris(4-benzoate) ligand with varying pH.