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Extreme temperature exposure can have a considerable impact on the health of older adults. China, which has entered a deeply aging society, may be obviously threatened by extreme weather. Based on data obtained from the China Health and Retirement Longitudinal Study, we apply a panel fixed effect model to investigate the impact of extreme temperature on medical costs for older adults. The results reveal a U-shaped relationship between temperature and older adults’ medical costs. Heterogeneity analysis indicates that medical costs for older adults in the South and older adults in rural areas are more significantly affected by low temperatures, mainly due to lower per capita heating facilities. Furthermore, the medical costs of older people with lower education levels are also more susceptible to temperature fluctuations. Our simulated prediction indicates that the medical costs of older adults in 2050 will be 2.7 trillion Chinese yuan under the RCP8.5 scenario, but can be reduced by 4.6% and 7.4% following RCP4.5 and RCP2.6 scenarios, respectively. Compared with base period, the medical costs of older adults in western provinces such as Guangxi and Sichuan will more than triple by 2050. Policymakers should prioritize addressing the health needs of these vulnerable groups and less developed regions with less adaptive capacity.

Metal organophosphonates have been explored in energy-related fields due to their high chemical and thermal stability as a type of uniformly precursor, but only few of pristine metal organophosphonate are directly used for oxygen evolution reaction (OER) catalysts. Here, a mixed-valence iron phosphonate (Fe3-ppat) has been constructed and applied to OER catalysis considered the potential active sites in pillars FeII(H2O)4(COO)2 and inorganic layers FeIII(μ2–OH)PO3. Specifically, isostructural trimetallic framework Fe1.7Co0.3Ni1.0-ppat possesses a minimum overpotential (291 mV), small Tafel slope (91.65 mV dec−1), and high stability up to 83 h. The enhanced catalytic performance could be mainly ascribed to the synergistic effect of NiII equivalent occupancy in pillars and Co/FeIII in layers.

In the title compound, [Fe(C6H12NO5)2], the FeII ion lies on an inversion center and is coordinated by two N atoms and four O atoms from two tridentate N-[2-hydroxy-1,1-bis(hydroxymethyl)ethyl]glycine ligands, forming a slightly distorted octahedral coordination environment. In the crystal, O—H...O, O—H...N and weak C—H...O hydrogen bonds link molecules, forming a three-dimensional network.

The synthesis of two isostructural mixed-valence vanadium(III/IV) phosphonoacetates [H.sub.2](DABCO)[(V.sup.IV)O({H.sub.2}O)(V.sup.III)(OH)({O.sub.3}PC{H.sub.2}C{O.sub.2}).sub.2]).2.5[H.sub.2]O and [H.sub.2](PIP)[V.sup.IV]O([H.sub.2].O)[(V.sub.III)(OH)([O.sub.3)PC{H.sub.2}C{O.sub.2}.sub.2]).2.5[H.sub.2] is presented. Results demonstrate reveal that the phosphonoacetates have a three-dimensional (3D) open framework featuring 16-ring ellipsoid channels that are filled with doubly protonated 1,4-diazabicyclo[2,2,2]octanium/piperazinium cations and water molecules.

Stimuli-responsive solid-state crystal dynamics or flexibility in metal-organic frameworks (MOFs) showing multiple structure changes is an arising interest for understanding the structure-property relationship and designing functional materials. In this article, dehydration-induced stepwise single-crystal to single-crystal (SC-SC) transformations are observed in two-dimensional 63-topological coordination polymer [Co(H2L)(H2O)2]·H2O ( 1 >), where H4L is 3,5-bis(3′,5′-dicarboxylphenyl)-1 H -1,2,4-triazole. Upon thermal dehydration at 130 °C for 2 h, half lattice water in 1 > can be released to form [Co(H2L)(H2O)2]·0.5H2O ( 2 >). By increasing dehydration temperature to 150 °C for 3 h, the third phase [Co(H2L)(H2O)2] ( 3 >) that is free of lattice water molecule is gained. Further increasing the dehydration temperature to 160 °C for 6 h, one of coordination water molecule can be released, giving rise to dicobalt-based 2D (3,6)-connected kgd double layer [Co(H2L)(H2O)] ( 4 >). During stepwise dehydration SC-SC transformation courses, coordination sphere of Co(II) changes from penta-coordinate trigonal bipyramid to hexa-coordinate octahedra; H2L2- ligates from (κ1)-(κ1)-(κ1)−μ3-H2L2-, (κ1)-(κ1)-(κ2)−μ3-H2L2- to (κ1-μ2)-(κ1)-(κ2)−μ4-H2L2-; network topology ranges from 3-connected 63- hcb to (3,6)-connected kgd ; magnetism changes from single-ion behavior of Co(II) to intradicobalt ferromagnetism. [ABSTRACT FROM AUTHOR]

Although a variety of functional metal-organic frameworks (MOFs) have been synthesized, post-modified, and applied in various areas, there is little knowledge about how molecular cluster building units are stepwise evolved into MOFs via intermediates. Coordination bonds are generally stronger than hydrogen bonds, and thus equivalent replacement of X-H···Y hydrogen bonds by X-M-Y coordination bonds can transform hydrogen bond networks into MOFs. In this work, solvothermal in situ reduction reactions of CuBr2 and 1,4-diazoniabicyclo[2,2,2]octane (DABCO) generated a myriad of tunable photoluminescent cuprous body-centered cubic bromide cluster-based networks with the general formula [Cu4+xH4-xBr6(DABCO)4](HCO2)2·S (x = 0, 0.56, 0.81, 1.27, 1.39, 2.56, 2.78, and 4 for compounds 1-8, respectively). All of these compounds crystallize in the cubic space group with the largest volume difference being only 5.2%, but they belong to three remarkably different kinds of crystals. Complex 1 is a molecular crystal and consists of tetrahedral [Cu4Br6(HDABCO)4]2+ clusters with monodentate HDABCO groups that are supported via N-H···Br synthons in the hydrogen bond network. Compound 8 is a [Cu8Br6]2+ cube cluster-based MOF with bridged DABCO ligands. Complexes 2-7 are seemingly impossible Cu/H-substituted solid solutions of 1 and 8. The CuBr framework components in 1-8 are Cu4Br6, Cu4.56Br6, Cu4.81Br6, Cu5.27Br6, Cu5.39Br6, Cu6.56Br6, Cu6.78Br6, and Cu8Br6, respectively. Crystallization kinetics studies revealed that the [Cu4Br6(HDABCO)4]2+ cluster-based hydrogen bond network (1) was initially formed such that N-H···Br hydrogen bonds could be stepwise replaced by N-Cu-Br coordination bonds to form the [Cu8Br6]2+ cube cluster-based MOF (8) via solid solutions. These observations directly reveal the equivalence and transformation between the N-H···Br hydrogen bond and the N-Cu-Br coordination bond and the evolutionary mechanism of a molecular crystal to a MOF via solid solutions, which is of fundamental importance in materials but has never before been revealed. DFT calculations suggest that equivalent replacement of a N-H···Br hydrogen bond by a N-Cu-Br coordination bond is exothermic and exergonic, which also supports the transformation from molecule 1 to MOF 8. [ABSTRACT FROM AUTHOR]

Seven cupric halide coordination polymers, namely [Cu5(OH)3Br3(ina)4] (1), [Cu5(OH)3Cl3(ina)4] (2), [Cu2(OH)Cl(ina)2] (3), [Cu3(OH)2Cl2(ina)2]·2H2O (4), [Cu3(OH)2Br2(ina)2]·2H2O (5), [Cu2Cl2(ina)2(H2O)2] (6), [Cu2Cl(ina)2(gca)(H2O)] (7), cupric complex templated cuprous halide [CuII(Me-ina)2(H2O)][Cu5IBr7] (8), and organic templated cuprous halide Me2-ina[Cu2Br3] (9) (Hina = isonicotinic acid), were prepared from the starting materials of cupric halide and Hina via fine-tuning solvothermal reactions. According to valence states of copper, 1-7 are copper(II) complexes, 8 is a mixed-valent Cu(I,II) complex, while 9 is a Cu(I) compound. According to bonding types of halides, nine complexes can be classified as three types: complexes 1-3 include only normal X-Cu bond (X = halide); complexes 4-7 include normal X-Cu bond and X···Cu weak bond; complexes 8 and 9 include normal X-Cu bond and X···H-C halogen hydrogen bonds. Complexes 1 and 2 are isomorphic three-dimensional (3D) pcu topological metal organic frameworks (MOFs) with butterfly-like Cu4(μ3-OH)2X2 and steplike Cu6(μ3-OH)4 cores as nodes, showing strong ferromagnetic couplings. Complex 3 also is a pcu topological MOF with only butterfly-like Cu4(μ3-OH)2Cl2 clusters as nodes, presenting spin canting antiferromagnetic behavior. Isostructural 4 and 5 are Cu3(OH)2 clusters based two-dimensional (2D) (4,4) layers, which are extended into 3D eight-connected networks via weak Cu···X bonds, showing ferromagnetic coupling. Antiferromagnetic 6 is a simple one-dimensional coordination polymer, which is extended via weak Cu···Cl bonds into 3D (3,4)-connected networks. Paramagnetic 7 is a ladderlike polymer, which is extended into 2D (3,4)-connected layer via weak Cu···Cl bonds. The syntheses of polymeric cupric complexes 1-7 mainly result from differences in reactant ratio and pH value. Utilization of reducing methanol generated novel cubane-containing [Cu5Br7]2- chain templated by paddlewheel-like [CuII(Me-ina)2]2+ 8 and face-shared dimer-containing [Cu2Br3]- chain templated by N-methylated and O-esterificated Me2-ina 9. Complex 9 exhibits a strong red emission and a weaker green emission upon excitation. [ABSTRACT FROM AUTHOR]

By using environmental friendly K3[Fe(CN)6] as a cyanide source, hydrothermal reactions of CuCl2and diamines resulted in four Cu2(1,1,2-μ3-CN)2(CN)4dimer-based organic templated cuprous cyanide open frameworks, namely, [H1.5mepip]2[Cu4(CN)7] (1), [H1.5etpip]2[Cu4(CN)7] (2), [H2me2pip][Cu3(CN)5] (3), and [H2dmpa][Cu4(CN)6] (4) (mepip = N-methylpiperazine; etpip = N-ethylpiperazine, me2pip = N,N-dimethylpiperazine, dmpa = 3-dimethyl-aminopropylamine). Isomorphic 1and 2show three-dimensional (3-D) (4,6)-connected FeS2-like open frameworks constructed by 4-connected Cu(CN)4monomers and 6-connected Cu2(CN)6dimers. Complex 3shows an unprecedented 3-D (4,6)-connected open framework in which the ratio of 4-connected Cu(CN)4monomers to 6-connected Cu2(CN)6dimers is 1:1. Complex 4shows a 3-D (3,6)-connected AgIn2-like open framework constructed by 3-connected Cu(CN)3monomers and 6-connected Cu2(CN)6dimers. Different from CuCN/amine coordination polymers, the protonated organic diamines in 1–4act as templates in the formation of cuprous cyanide open frameworks. Even at ambient temperature, 1, 2, 3, and 4show strong blue-green photoluminescence related to Cu2(CN)6dimer, which is mainly assigned to metal-to-ligand charge-transfer (MLCT) by time-dependent density functional theory (TD-DFT) and electronic band structure calculations. [ABSTRACT FROM AUTHOR]

Two isostructural mixed-valence vanadium phosphonoacetates H2(DABCO)[VIVO(H2O)VIII(OH)(O3PCH2CO2)2]•2.5H2O (1) and H2(PIP)[VIVO(H2O)VIII(OH)(O3PCH2CO2)2]•2.5H2O (2) have been synthesized. They crystallize in the orthorhombic space group Pnna with a = 7.0479(10) Å, b = 15.307(2) Å, and c = 17537(3) Å for 1 and a = 7.0465(9) Å, b = 15.646(2) Å, and c = 17396(2) Å for 2. X-ray single-crystal diffraction reveals that 1 and 2 have a three-dimensional open framework featuring 16-ring ellipsoid channels that are filled with doubly protonated 1,4-diazabicyclo[2,2,2]octanium/piperazinium cations and water molecules. According to the classification in metal-organic frameworks, 1 and 2 contain infinite (-O-V-)∞ chains that are cross-linked by "metalloligand" [VO(H2O)(O3PCH2CO2)2]4- into a 3-D net of the sra topology. The temperature dependence of the magnetic susceptibility of 1 shows that the χmT value in the range of 60-320 K is constant of 1.105 cm³ K mol-1/V2 unit, and upon further cooling, the χmT value rapidly increases to 1.81 cm³ K mol-1 at 2 K. The corresponding effective magnetic moment (μefl)/V2 unit varies from 2.97 μB at 320 K to 3.80 μB at 2 K. The magnetic data in the range of 2-320 K follow the Curie-Weiss law with C = 1.074 cm³ K mol-1 and Θ = -1.34 K. [ABSTRACT FROM AUTHOR]

Seven new metal phosphonoacetates, namely, [Zn7(OH)2(ppat)4(H2NH2] (1), H3O[Zn(ppat)] (2), [Zn3(4,4‘-bpy)(ppat)2] (3), H2dmpz0.5[Zn(ppat)]·H2O (4), (H3NH2[Co3(OH)2(ppat)2] (5), H24,4‘-bpy[VIV2O2(ppat)2] (6), and [D'III(ppat)(H2NH] (7) (H3ppat = phosphonoacetic acid, 4,4‘-bpy = 4,4‘-bipyridine, dmpz = N,N‘-dimethylpiperazine) were hydrothermally synthesized by the in situ hydrolysis of triethyl phosphonoacetate route. X-ray crystallography reveals that 1 shows a two-dimensional layered structure containing octahedral, tetrahedral, and trigonal bipyramidal Zn sites and an unprecedented inorganic Zn−O ribbon; 2 has a three-dimensional framework with one-dimensional dumbbell-shaped channels encapsulating protonated water molecules; 3 is a neutral three-dimensional framework constructed by [Zn(4,4‘-bpy)]n2n+ chains and [Zn(ppat)]nn- layers, two types of structural motifs; 4 shows a three-dimensional hydrogen bond network constructed by [Zn(ppat)]- anionic layers and N,N‘-dimethylpiperazinium cations; 5 is a layered structure containing inorganic Co−O chains consisting of edge-shared CoO6 octahedra; 6 has a 3D hydrogen bond array constructed from [V2O2(ppat)]n2n- layers and doubly protonated 4,4‘-bpy cations; 7 crystallizes in a chiral space group and has a 3D four-connected framework with diamond topology. Magnetic measurements reveal antiferromagnetic behavior for 5, paramagnetic behavior for 6, and canted antiferromagnetic behavior for 7-i [ABSTRACT FROM AUTHOR]