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1.
Chem Soc Rev ; 53(11): 5626-5676, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38655667

RESUMEN

Metalation of metal-organic frameworks (MOFs) has been developed as a prominent strategy for materials functionalization for pore chemistry modulation and property optimization. By introducing exotic metal ions/complexes/nanoparticles onto/into the parent framework, many metallized MOFs have exhibited significantly improved performance in a wide range of applications. In this review, we focus on the research progress in the metalation of metal-organic frameworks during the last five years, spanning the design principles, synthetic strategies, and potential applications. Based on the crystal engineering principles, a minor change in the MOF composition through metalation would lead to leveraged variation of properties. This review starts from the general strategies established for the incorporation of metal species within MOFs, followed by the design principles to graft the desired functionality while maintaining the porosity of frameworks. Facile metalation has contributed a great number of bespoke materials with excellent performance, and we summarize their applications in gas adsorption and separation, heterogeneous catalysis, detection and sensing, and energy storage and conversion. The underlying mechanisms are also investigated by state-of-the-art techniques and analyzed for gaining insight into the structure-property relationships, which would in turn facilitate the further development of design principles. Finally, the current challenges and opportunities in MOF metalation have been discussed, and the promising future directions for customizing the next-generation advanced materials have been outlined as well.

2.
Inorg Chem ; 63(2): 1142-1150, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38175800

RESUMEN

It is still challenging to construct novel photochromic and photomagnetic materials in the field of molecular materials. Herein, the 2,4,6-tris-2-pyridyl-1,3,5-triazine (TPTz) molecule was found to display photochromic properties under room temperature light irradiation. Two mononuclear structures, [Ni(H2O)(TPTz)(C2O4)]·2H2O (1; C2O42- = oxalate) [Ni(H2O)(TPTz)(C2O4)]·0.5H2O (2), and one chain compound [Ni(TPTz)(H2-HEDP)]·2H2O (3; HEDP = hydroxyethylidene diphosphonate) were obtained by assembling TPTz with polydentate O-ligands (oxalate and phosphonate) and the paramagnetic Ni2+ ions. The electron-transfer (ET)-dominated photochromism was observable in 1 and 2 after light irradiation with the photogeneration of relatively stable radicals, and the resultant photochromism was demonstrated via UV-vis, photoluminescence, X-ray photoelectron spectra, electron paramagnetic resonance spectra, and molecular orbital calculations. Due to the denser stacking interactions between the adjacent organic molecules, 2 exhibited a faster photochromic rate than 1. Compared with 1 and 2, compound 3 did not show photochromic behavior, which was deciphered by the theoretical calculations for all of the compounds. Importantly, the magnetic couplings appeared between photogenerated radicals and paramagnetic Ni2+ ions, resulting in a scarcely photomagnetic phenomenon of 1 and 2 in the Ni-based electron transfer photochromic materials. This work enriches the available kind of ligands for the design of ET photochromic materials, putting forward a method to tune the electron transfer photochromic efficiency in the molecular materials.

3.
Cell Mol Neurobiol ; 43(3): 1037-1048, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35792991

RESUMEN

Retinitis pigmentosa (RP) is a group of genetic disorders resulting in inherited blindness due to the degeneration of rod and cone photoreceptors. The various mechanisms underlying rod degeneration primarily rely on genetic mutations, leading to night blindness initially. Cones gradually degenerate after rods are almost eliminated, resulting in varying degrees of visual disability and blindness. The mechanism of cone degeneration remains unclear. An understanding of the mechanisms underlying cone degeneration in RP, a highly heterogeneous disease, is essential to develop novel treatments of RP. Herein, we review recent advancements in the five hypotheses of cone degeneration, including oxidative stress, trophic factors, metabolic stress, light damage, and inflammation activation. We also discuss the connection among these theories to provide a better understanding of secondary cone degeneration in RP. Five current mechanisms of cone degenerations in RP Interactions among different pathways are involved in RP.


Asunto(s)
Células Fotorreceptoras Retinianas Conos , Retinitis Pigmentosa , Humanos , Células Fotorreceptoras Retinianas Conos/metabolismo , Células Fotorreceptoras Retinianas Bastones/metabolismo , Retinitis Pigmentosa/genética , Retinitis Pigmentosa/metabolismo , Retinitis Pigmentosa/terapia , Ceguera/metabolismo , Estrés Oxidativo
4.
Inorg Chem ; 62(22): 8663-8669, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37222238

RESUMEN

Photochromic metal-organic complexes (PMOCs) have received huge attention of chemists, thanks to their diverse structural characteristic and various available photo-modulate physicochemical functionalities. The organic ligand plays a crucial role in the quest of PMOCs with specific photo-responsive functionalities. The multiple coordination modes of polydentate ligands also provide possibilities for forming isomeric MOCs, which may open a new perspective on the research of PMOCs. The exploration of suitable PMOC systems is significant for the yield of isomeric PMOCs. Taking into account extant PMOCs based on polypyridines and carboxylate as electron acceptors (EAs) and donors (EDs), the covalent fusion of suitable pyridyl and carboxyl species may produce single functionalized ligands bearing ED and EA moieties for the building of novel PMOCs. In this study, the coordination assembly of bipyridinedicarboxylate (2,2'-bipyridine-4,4'-dicarboxylic acid, H2bpdc) and Pb2+ ions generate two isomeric MOCs, [Pb(bpdc)]·H2O (1 and 2), which have the same chemical compositions with main discrepancies in the coordination mode of bpdc2- ligands. As expected, supramolecular isomers 1 and 2 exhibited different photochromic performance, thanks to the distinct microscopic functional structural units. A schematic encryption and anti-counterfeiting device based on complexes 1 and 2 has also been studied. Compared with the extensively studied PMOCs supported by photoactive ligands like pyridinium and naphthalimide-derivatives and PMOCs derived from mixed electron-accepting polydentate N-ligands and electron-donating ligands, our work provides a new idea for building PMOCs based on pyridinecarboxylic acid ligands.

5.
Microb Pathog ; 165: 105459, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35231569

RESUMEN

Cryptosporidium spp. is recognized as an opportunistic zoonotic parasite that infects humans, wild and domestic animals, and is also a major cause of diarrhea-related disease in immunocompromised individuals, considered a global public health concern. Pig is considered as one of the reservoir hosts of Cryptosporidium spp. can transmit cryptosporidiosis to humans and other animals. However, limited studies on the distribution of Cryptosporidium spp. in diarrheic pigs have been published. Objective of the current study was to investigate the infection and species/genotypes of Cryptosporidium spp. from feces of diarrheic pigs in southern China. A total of 1254 fresh fecal samples were collected from 37 intensive pig farms in Jiangxi, Hunan and Fujian provinces, and were screened for Cryptosporidium spp. infection using a nested PCR assay targeted the small subunit rRNA (SSU rRNA) genes. The overall infection rate of Cryptosporidium spp. was 4.5% (57/1254), including 5.5% (17/307) in suckling piglets, 2.7% (8/299) in weaned piglets, 7.4% (7/95) in fattening pigs and 4.5% (25/553) in sows, respectively. In addition, two human-pathogenic species Cryptosporidium scrofarum (80.7%, 46/57) and Cryptosporidium suis (19.3%, 11/57) were identified. C. scrofarum and C. suis were observed in pigs tested in all age groups. Interestingly, a high colonization incidence of C. scrofarum (16/57) was observed in suckling piglets. This study revealed the prevalence and species of Cryptosporidium spp. in diarrheic pigs in three provinces of southern China, which suggested that diarrhea maybe not a direct factor affecting the prevalence of Cryptosporidium spp. in pigs. More prevention and control of this parasite in pigs should receive greater attention from farmers in investigated provinces.


Asunto(s)
Criptosporidiosis , Cryptosporidium , Enfermedades de los Porcinos , Animales , China/epidemiología , Criptosporidiosis/epidemiología , Criptosporidiosis/parasitología , Cryptosporidium/genética , Diarrea/epidemiología , Diarrea/veterinaria , Heces/parasitología , Femenino , Genotipo , Prevalencia , Porcinos , Enfermedades de los Porcinos/epidemiología
6.
Inorg Chem ; 61(21): 8379-8385, 2022 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-35592931

RESUMEN

Hybrid photochromic materials (HPMs) with specific photoresponsive functionality have applications in many fields. The photoinduced electron-transfer (ET) strategy has been proved to be effective in the synthesis of HPMs with diverse photomodulated properties. The exploitation of new electron acceptors (EAs) is meaningful for promoting the development of HPMs. In this work, we introduced a rigid tetraimidazole derivative, 3,3,5,5-tetra(imidazol-1-yl)-1,1-biphenyl (TIBP) as a potential EA, into a metal-diphosphonate (1-hydroxyethylidene-1,1-diphosphonic acid, H4-HEDP) system to explore HPMs and finally obtained a hybrid metal phosphonate (H4-TIBP)0.5·[Dy(H-HEDP) (H2-HEDP)]·H2O (1). 1 features anionic chains composed of diphosphonate and Dy3+ ions. The extra charge is balanced by protonated TIBP cations, which exist in the void of adjacent chains and form H-bonds with Ophosphonate (N-H···O). Upon photostimulation with a Xe lamp (300 W), the crystalline sample 1 exhibited coloration by changing from colorless to pale yellow because of the presence of photoinduced radicals that originated from the ET from Ophosphonate to NTIBP. Along with the coloration, photomodulated fluorescence, magnetism, and proton conductivity were also detected in the photoactivated samples. Different from the reported HPMs based on polypyridine derivatives and photoactive species such as pyridinium and naphthalimide derivatives as EAs, our study provides a new category of EA units to yield HPMs with fascinating photoresponsive functionality via the assembly of polyimidazole derivatives and phosphonate-based supramolecular building blocks.

7.
Inorg Chem ; 61(43): 17178-17184, 2022 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-36263997

RESUMEN

Room-temperature phosphorescence (RTP) materials have widespread applications in biological imaging, anticounterfeiting, and optoelectronic devices. Because of the predesignability of metal-organic complexes (MOCs), the RTP materials based on MOC systems have received huge attention from researchers. The coordinate anchoring of luminophores to enhance the rigidity of organic molecules and restrict the nonradiative transition offers opportunities for generating MOC materials with captivating RTP performance. Hitherto, most of the MOC-based RTP materials feature a single luminophore ligand. The development of new MOC systems with RTP functionality is still challenging. Herein, we use the mixed-ligand synthetic strategy to produce isostructural MOCs, [Zn(TIMB)(X2-TPA)]·H2O (1, X = Cl; 2, X = Br; TIMB = 1,3,5-tris(2-methyl-1H-imidazol-1-yl)benzene; H2-X2-TPA = 2,5-dichloroterephthalic and 2,5-dibromoterephthalic acid), and modulate the RTP properties of resultant products via the synergy of coordinate anchoring and substitution synthesis. 1 and 2 feature similar coordination layers composed of neutral TIMB and anionic X2-TPA2- ligands, which provide a good structural model to tune the RTP performances of final products via substitution synthesis. Different from the reported RTP materials based on MOC systems, our study provides a general way to build and modulate MOC-based RTP materials with the assistance of coordinate anchoring and substitution synthesis strategies.


Asunto(s)
Luminiscencia , Temperatura , Ligandos
8.
Inorg Chem ; 61(35): 14148-14155, 2022 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-35998664

RESUMEN

The assembly of a tetradentate pyridine-derived ligand with CuX has afforded two isostructural Cu(I)-organic frameworks [Cu2X2(TBD)·DMF]n (X = Cl for 1 and Br for 2) in this work. Structural analysis indicates that the compounds feature hybrid layered architectures, and the three-dimensional supramolecular frameworks are finally fabricated through the alternative stacking of adjacent layers wherein large open channels are simultaneously constructed. The chemical stability has been studied showing the excellent skeleton maintenance of the prepared solids in various solvents and even in water. Moreover, the iodine and dye sorption performance for compound 1 has been further tested. The Cu(I)-based metal-organic framework exhibits outstanding sorption and separation abilities on the targeted species, which could be considered as a promising adsorbent with high efficiency and selectivity.

9.
Inorg Chem ; 61(45): 18311-18317, 2022 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-36306476

RESUMEN

The rational design of 2D polyoxometalate-based metal-organic framework (POMOF) nanosheets on a conductive substrate as a self-supporting electrode is highly attractive but a great challenge. Herein is the first demonstration of POMOF nanopillar arrays consisting of 2D nanosheets as a self-supported electrode for the hydrogen evolution reaction (HER) in acidic conditions. Single-crystal X-ray analysis reveal that our as-prepared 2D [Co2(TIB)2(PMo12O40)]·Cl·4H2O [named CoMo-POMOF; TIB = 1,3,5-tris(1-imidazoly)benzene] crystalline materials are connected by Co-α-Keggin polymolybdate units act as secondary building blocks and TIB as the organic ligands. The 2D CoMo-POMOF nanosheets were successfully arrayed on a conductive nickel foam substrate by a facile CoO nanorod template-assisted strategy. Remarkably, the CoMo-POMOF nanopillar arrays demonstrate superior electrocatalytic performance toward the HER with an overpotential of 137 mV and Tafel slope of 59 mV dec-1 at 10 mA cm-2, which are comparable to those of state-of-the-art POMOF-based electrocatalysts. Density-functional theory (DFT) calculations demonstrate that the exposed bridging oxygen active sites (Oa) of Co-α-Keggin polymolybdate units in CoMo-POMOF optimize the Gibbs free energy of H* adsorption (ΔGH* = -0.11 eV) and increase the intrinsic HER activity.

10.
Mol Med ; 27(1): 12, 2021 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-33546582

RESUMEN

BACKGROUND: Osteoarthritis (OA) is the most common articular disorder, leading to joint malfunction and disability. Although the incidence of OA is increasing globally, the treatment of OA is very limited. LncRNA CIR has been implicated in OA through unclear mechanisms. Here, we investigated the role of lncRNA CIR in chondrogenic differentiation. METHODS: Human umbilical-cord-derived mesenchymal stem cells (hUC-MSCs) were obtained from human umbilical cords. Flow cytometry was used to analyze the surface markers of hUC-MSCs. Various culture conditions and corresponding staining assays were employed to assess the differentiation abilities of hUC-MSC. qRT-PCR, western blot, and immunostaining were used to measure expression levels of related genes and proteins such as lncRNA CIR, ATOH8, EZH2, and H3K27me3. RNA immunoprecipitation assay, biotin pull-down, and chromatin immunoprecipitaion assay were performed to analyze the interactions of lncRNA CIR, EZH2, H3K27me3 and ATOH8 promoter. RESULTS: hUC-MSCs exhibited MSCs features and could differentiate into chondrocytes under specific conditions. LncRNA CIR was downregulated while ATOH8 was upregulated during the chondrogenic differentiation of hUC-MSCs. Knockdown lncRNA CIR or overexpression of ATOH8 promoted chondrogenic differentiation. Further, lncRNA CIR bound to EZH2 and repressed ATOH8 expression via EZH2-mediated H3K27me3, which promotes the methylation of ATOH8. Inhibition of ATOH8 reversed the effects of knockdown lncRNA CIR on chondrogenic differentiation. CONCLUSION: LncRNA CIR suppresses chondrogenic differentiation of hUC-MSCs. Mechanistically, lncRNA CIR could inhibit ATOH8 expression that functions to promote chondrogenic differentiation through EZH2-mediated epigenetic modifications.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Condrocitos/citología , Proteína Potenciadora del Homólogo Zeste 2/genética , Células Madre Mesenquimatosas/citología , ARN Largo no Codificante/genética , Adulto , Diferenciación Celular , Células Cultivadas , Condrocitos/metabolismo , Condrogénesis , Metilación de ADN , Epigénesis Genética , Femenino , Histonas , Humanos , Células Madre Mesenquimatosas/metabolismo , Embarazo , Regiones Promotoras Genéticas
11.
Chemistry ; 27(14): 4709-4714, 2021 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-33428231

RESUMEN

As a significant class of photochromic materials, crystalline hybrid photochromic materials (CHPMs) have attracted widespread attention of researchers because of their possibilities for generating other photoresponsive properties and advantages in understanding the underlying relationship between structure and photoresponsive performance. The predesign of suitable ligands plays a major role in generating desirable CHPMs. Hitherto, most CHPMs have been built from photodeformable or photoresponsive tectons. However, the synthesis of these ligands is usually time-consuming and expensive, and this greatly restricts their large-scale preparation and practical application. Therefore, it is necessary to explore new families of CHPMs besides the existing CHPMs. Herein, a simple and general method for constructing CHPMs by decorating metal nitrate with a coplanar bipyridine moiety, namely 1,10-phenanthroline (phen), is reported. The resulting products exhibit photocoloration in response to Xe-lamp irradiation. The electron transfer (ET) from the coplanar NO3 - species (as π-electron donors, π-EDs) to coplanar phen moieties (as π-electron acceptors, π-EAs) is responsible for the resulting photochromism. The influence of the coordination environment and central metal ion on the photochromism was also studied. This work demonstrates that the introduction of coplanar organic tectons as π-EAs to metal nitrates as π-EDs with the collaboration of ET and coordination-assembly strategies is a simple and general method to manufacture CHPMs.

12.
Chemistry ; 27(29): 7842-7846, 2021 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-33780056

RESUMEN

As promising photoresponsive materials and potential smart materials, hybrid photochromic materials (HPMs), especially for crystalline HPMs (CHPMs), have been broadly explored for their potential in inheriting the merits of each constituents, and intriguing photomodulated functionality. Hitherto, the photoresponsive functionality in explored CHPMs mainly concentrate on dyad combination. By contrast, triple or quadruple photoresponsive properties are very rare because of the limited compatibility of multiple photoresponsive functionality in a single system. In this work, the electron-transfer (ET) and crystal engineering strategies were utilized to predesign CHPMs with multiple photoresponsive properties via the collaboration of paramagnetic metal ion (Dy3+ ), electron-donor (ED) ligand (benzene-1,2,3-tricarboxylic acid, H3 BTA) and electron-acceptor (EA) ligand (1,10-phenanthroline, phen). The resulting complex [Dy(BTA)(phen)2 ]⋅2H2 O (1) shows hybrid chain with the intrachain Dy3+ ions bridged and chelated by tricarboxylate and phen ligands, respectively. After photostimuli, the ET between tricarboxylate and phen results in photogenerated radicals and the resultant quadruple photoresponsive properties. Considering the abundant resources of paramagnetic metal ions, ED- and EA-ligands, this work provides a general method to construct CHPMs with multiple photoresponsive performances via the collaboration of each unit under the guidance of ET and crystal engineering strategies.

13.
Chemistry ; 27(4): 1410-1415, 2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33037733

RESUMEN

The intermarriage of neutral and tripodal imidazole ligand, tris(4-(1H-imidazol-1-yl)phenyl)amine (TIPA), with zinc phosphite yields two hybrid phosphites, [Zn2 (HPO3 )2 (TIPA)]⋅2 H2 O (1) and [Zn3 (HPO3 )3 (TIPA)]⋅6 H2 O (2). Compound 1 has a hybrid sheet with neutral zinc-phosphite chains as supramolecular building blocks (SBBs), whereas 2 exhibits a 3D hybrid architecture with other neutral zincophosphite chains as supramolecular building blocks. The structural discrepancy between 1 and 2 is mainly due to the distinct linkage modes between organic TIPA ligands and inorganic zincophosphite chains. Interestingly, compounds 1 and 2 feature fast photochromism in response to UV light irradiation under ambient conditions. The discrepancy of photochromic performance between 1 and 2 is mainly due to the different geometrical configuration of the TIPA ligand. Different to majority of reported hybrid photochromic compounds driven by photochromic active units, the photochromism in 1 and 2 is derived from the electron transfer (ET) between phosphite and non-photochromic triimidazole-derivative ligand TIPA. Compared with the widely explored nonphotochromic polypyridine-derivative as electron acceptors (EAs), our work provides a new EA model for the design of hybrid photochromic materials based on the ligand-to-ligand ET mechanism. A multiple anti-counterfeiting application based on 1 and 2 was investigated.

14.
Inorg Chem ; 60(7): 4375-4379, 2021 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-33729790

RESUMEN

Herein, we report a dia-type metal-organic hybrid network based on the [Ag4Br6] clusters and hexamethylenetetramine molecules wherein both the inorganic nodes and organic linkers feature adamantane-like geometry with a Td symmetry. The silver bromine complex presents a dual emission and exhibits an interesting luminescent thermochromism behavior. Remarkably, white-light emission can be readily realized through variation of the temperature. In addition, the title compound is expected to be competent as a luminescent thermometer for temperature identification.

15.
J Am Chem Soc ; 142(5): 2682-2689, 2020 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-31955567

RESUMEN

Exploitation of room temperature (RT) photochromism and photomagnetism to induce single-molecule magnet (SMM) behavior has potential applications toward optical switches and magnetic memories, and remains a tremendous challenge in the development of new bulk magnets. Herein, a series of chain complexes [Ln3(H-HEDP)3(H2-HEDP)3]·2H3-TPT·H4-HEDP·10H2O (QDU-1; Ln = Dy (QDU-1(Dy)), Gd (QDU-1(Gd)), and Y (QDU-1(Y)); HEDP = hydroxyethylidene diphosphonate; TPT = 2,4,6-tri(4-pyridyl)-1,3,5-triazine) were synthesized by solvothermal reactions. All the compounds exhibited reversible photochromic and photomagnetic behaviors via UV light irradiation at RT, induced by the photogenerated radicals via a photoinduced electron transfer (PET) mechanism. More importantly, the PET process induced significant variations in magnetic interactions for the Dy(III) congener. Strong ferromagnetic coupling with remarkably slow magnetic relaxation without applied dc fields was observed between DyIII ions and photogenerated O• radicals, showing SMM behavior after RT illumination. For the first time, we observed the reversible RT photochromism and photomagnetism in the lanthanide-based materials. This work realized the radicals-actuated on/off SMM behavior via RT light irradiation, providing a new strategy for constructing the light-induced SMMs.

16.
Inorg Chem ; 59(2): 972-975, 2020 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-31916756

RESUMEN

Room-temperature phosphorescence (RTP) materials have potential applications in anticounterfeiting, biochemistry, and optical recording. It is significant to develop a novel approach to enriching RTP materials. Here two new hybrid RTP solids were obtained by the introduction of organic 1,3,5-tris(1-imidazolyl)benzene and halogen atoms to simultaneously coordinate with inorganic moieties. Single-crystal X-ray analysis reveals that Br atoms are oriented toward the adjacent organic molecules that can play an important heavy-atom effect (HAE). Notably, such a HAE realized by orienting the Br atom to the location immediately adjacent to the triplets produced can efficiently facilitate intersystem crossing and results in RTP with intensity similar to that of the fluorescence in steady-state photoluminescence.

17.
Inorg Chem ; 58(2): 1184-1190, 2019 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-30592220

RESUMEN

A series of heterometallic formate framework templated by amines were solvothermally prepared. They feature the formula of [AI][CrMII(HCO2)6] (AI = NH4H2OI and M = Mn for 1, AI = CH3NH3I and M = Fe for 2, AI = CH3NH2CH3I and M = Co for 3, AI = CH3NH3I and M = Ni for 4). The title compounds exhibit isostructural niccolite architectures with differences only in the host metal ions and guest amines. Tunable ferromagnetic (FO) strength was realized in the resulting framework under the guidance of orthogonal magnetic orbital analysis of CrIII (t2g3eg) and MII (t2g3eg2 for MnII, t2g4eg2 for FeII, t2g5eg2 for CoII, t2g6eg2 for NiII) ions. The magnetic ordering temperatures derived from the experimental magnetic measurements for 1-4 are lower than 2, 10.3, 7.6, and 22.0 K, respectively. Notably, thanks to the weak FO coupling between CrIII and MnII ions, compound 1 displays a large magnetocaloric effect bearing the maximum of magnetic entropy change (-Δ Smmax) up to 43.9 J kg-1 K-1 with Δ H = 7 T and T = 3.5 K, larger than most reported transition metal-based complexes and commercial gadolinium gallium garnet (Gd3Ga5O12) (-Δ Smmax = 38.4 J kg-1 K-1 with Δ H = 7 T). From 1, 2/3, to 4, an enhancement of the magnetic ordering temperature is observable due to the increasing strength of FO interactions between CrIII and MII ions. Our work provides a successful instance to modulate the strength of FO exchange via analyzing the orthogonal magnetic orbitals of heterometallic ions.

18.
Inorg Chem ; 58(14): 9476-9481, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-31267747

RESUMEN

Room-temperature phosphorescence (RTP) materials have gained much attention, because of their applications in chemical sensing, optoelectronics, and security systems. Transition-metal complexes, particularly those of IrIII, PtII, RuII, and AuI, have preciously been investigated in the quest for excellent RTP materials. Recently, the pure organic molecules caught the eyes of researchers. Although great achievement has been reached, expanding the available types of RTP materials and hunting for top-performing RTP materials are still significant to promote the development of RTP materials. In this work, we report a series of isostructural hybrid zincophosphite [Zn3(HPO3)2(tib)2]X2 (X- = Cl-, Br-, I-; tib = 1,3,5-tris(1-imidazolyl)-benzene), which feature a cationic host structure and an anionic guest (X-). Because of the restriction of molecular vibrations/rotations of organic luminogens (tib) and the heavy-atom effect of the guest halide ion (X-), the title compounds exhibit almost pure RTP with absolute phosphorescence quantum yields of 5.8%-9.1%. More interestingly, unique excitation-energy-dependent phosphorescence has been observed in these hybrid materials. The phosphorescence origin has also been illustrated by theoretical calculations. Our work provides new insights into the design of RTP materials. Considering the structural diversity together with the rich host-guest chemistry of metal-phosphite/phosphate, we offer a new avenue to explore superior crystalline RTP materials.

19.
Inorg Chem ; 58(3): 1746-1749, 2019 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-30666862

RESUMEN

The cationic [Pb4(OH)4]4+ cubane as a template was first introduced to the 3D iodocuprate network, which is fabricated from the alternative connection of infinite [Cu2I2] n chains and µ2-I linkers. Distinct from most of the photocatalysts with UV or visible light for the photocatalytic degradation of an organic pollutant, the target compound could accomplish this task under direct sunlight because of the introduction of photoactive species. Our work provides a promising strategy to generate superior photocatalysts via the encapsulation of photoactive units into open frameworks.

20.
J Clin Lab Anal ; 33(2): e22669, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30461062

RESUMEN

BACKGROUND: Cervical spondylotic myelopathy (CSM), a common degenerative disorder, is characterized by chronic progressive compression of the cervical spinal cord. The present case-control study aimed to explore the potential role of VDR-FokI and VDBP-Thr420Lys polymorphisms in the susceptibility to CSM in the Chinese population. METHODS: The study enrolled 318 CSM patients and 282 healthy individuals whose clinical data were retrospectively analyzed. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis was used to genotype VDR-FokI and VDBP-Thr420Lys polymorphisms. The severity of CSM was assessed using the Japanese Orthopaedic Association (JOA) score with magnetic resonance imaging (MRI) of cervical vertebra. A nonconditional binary logistic regression model was conducted for assessing the risk factors of CSM. RESULTS: Patients in the CSM group had longer time duration to bend over desk working than the control group. The ff genotype and f allele frequency of VDR-FokI were elevated in CSM patients. Elevated Ff + ff genotype and f allele frequency of VDR-FokI might increase the risk of CSM. The VDR-FokI polymorphism was associated with nucleus pulposus capillary invasion, necrosis, hyaline degeneration and fibrosis, genesis and hyperplasia of cartilage-like cells, and fibrocyst in the fibrous ring. The VDR-FokI and VDBP-Thr420Lys genotypes conformed to Hardy-Weinberg equilibrium which showed that VDR-FokI and VDBP-Thr420Lys had group representation characteristics. CONCLUSION: Binary logistic regression analysis confirmed that VDR-FokI polymorphism and the time to bend over desk working were risk factors of CSM. Our results indicate that VDR-FokI polymorphism may be closely associated with the risk of CSM.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Receptores de Calcitriol/genética , Enfermedades de la Médula Espinal/genética , Espondilosis/genética , Anciano , Estudios de Casos y Controles , China/epidemiología , Femenino , Predisposición Genética a la Enfermedad/epidemiología , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo Genético , Estudios Retrospectivos , Enfermedades de la Médula Espinal/epidemiología , Espondilosis/epidemiología
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