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1.
Biol Pharm Bull ; 42(12): 2083-2088, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31787723

RESUMO

Pharmacovigilance is important to monitor the safety of drugs. There are, however, problems with the quality of adverse drug reaction reports in China. This study aimed to analyze the quality of adverse drug reaction reports in China, identify the factors affecting it, and propose measures to improve it. In our study, the western province of Shaanxi, the central province of Hubei and the eastern province of Jiangsu were chosen as typical, and adverse drug reaction reports from these three provinces from 2015 to 2017 were systematically sampled. The sampling reports were scored and graded to assess their quality. The results showed that only 10.18% were considered high quality in a total of 3429 reports. There were statistically significant differences in quality by year, province, report type, report source, and occupation of the reporter (p < 0.001). Reports from Shaanxi were slightly poorer quality, and "new" and "serious" reports and those from pharmacists were higher quality. Five indicators were particularly poor quality: patient information, adverse drug reaction, reporter information, drug information and vigilance. In conclusion, the quality of adverse drug reaction reports in China still needs improvement. Factors affecting quality included timing, location, report type, report source, and reporter's occupation. It may be helpful to publicize the importance of monitoring adverse drug reactions and improve the knowledge of reporters.

2.
Inorg Chem ; 58(20): 13836-13842, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31578865

RESUMO

On the basis of the [Fe3(µ3-O)(COO)6] cluster and 3,3',5,5'-diphenyltetracarboxylic acid (H4BPTC), three novel metal-organic frameworks (MOFs), NJU-Bai25, NJU-Bai26, and NJU-Bai27 (NJU-Bai for Bai's group at Nanjing University ) with different (4,4,4,6)-, (4,4,4,4,4,6)-, and (4,4,6)-connected nets were obtained in different solvent systems, in which due to the steric hindrance of the coordinated solvents the conformations of BPTC gradually change from the planar to the torsional; thus, the pore sizes of those MOFs were also gradually narrowed. Interestingly, the MOFs show high thermal/chemical stabilities and selective CO2 adsorption: NJU-Bai27 exhibits larger CO2 uptake (5.0 and 13.8 wt %) at 298 K under 0.15 and 1 bar, whereas NJU-Bai26 has a higher selectivity for CO2/N2 (366).

3.
J Am Chem Soc ; 141(37): 14539-14543, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31469955

RESUMO

A pure-supramolecular-linker (PSL) approach for the formation of metal-organic frameworks (MOFs) was initially given, which was demonstrated by syntheses of two highly connected and isostructural MOFs, {Fe3O(TPBTM6-)(Cl)(H2O)2}∞ (TPBTM = N,N',N″-tris(isophthalyl)-1,3,5-benzenetricarboxamide) (NJU-Bai52, NJU-Bai for Nanjing University Bai group) and {Sc3O(TPBTM6-)(OH)(H2O)2}∞ (NJU-Bai53). Very interestingly, they exhibit exceptional thermal stability, water stability, and highly selective CO2 capture properties. In particular, NJU-Bai53 with higher uptakes (2.74 wt % at 0.4 mbar and 298 K, 7.67 wt % at 298 K and 0.15 bar) and higher selectivity may be an excellent candidate for CO2 capture.

4.
Chem Asian J ; 14(20): 3603-3610, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31166654

RESUMO

Amide-functionalized metal-organic frameworks (AFMOFs) as a subclass of MOF materials have received great interest recently because of their intriguing structures and diverse potential applications. In this work, solvothermal reactions between indium nitrate and two mixed-linkers afforded two new isoreticular 8-connected trinuclear indium-based AFMOFs of [(In3 O)(OH)(L2)2 (IN)2 ]⋅(solv)x (2-In) and [(In3 O)(OH)(L2)2 (AIN)2 ]⋅(solv)x (NH2 -2-In) (H2 L2=4,4'-(carbonylimino)dibenzoic acid and HIN=isonicotinic acid or HAIN=3-aminoisonicotinic acid), respectively. Moreover, by means of reticular chemistry, an extended network of [(In3 O)(OH)(L3)2 (PB)2 ]⋅(solv)x (3-In) (H2 L3=4,4'-(terephthaloylbis(azanediyl))dibenzoic acid, HPB=4-(4-pyridyl)benzoic acid) was also successfully realized after prolongation of the former dicarboxylate linker and HIN, resulting in a truly 8-connected isoreticular AFMOF platform. These frameworks were structurally determined by single-crystal X-ray diffraction (SCXRD). Sorption studies further demonstrate that 2-In and NH2 -2-In exhibit not only high surface areas and pore volumes but also relatively high carbon capture capabilities (the CO2 uptakes reach 60.0 and 75.5 cm3 g-1 at 298 K and 760 torr, respectively) due to the presences of amide and/or amine functional groups. The selectivity of CO2 /N2 and CO2 /CH4 calculated by IAST are 10.18 and 12.43, 4.20 and 4.23 for 2-In and NH2 -2-In, respectively, which were additionally evaluated by mixed-gases dynamic breakthrough experiments. In addition, high-pressure gas sorption measurements show that both materials could take up moderate amounts of natural gas.

5.
Chem Commun (Camb) ; 55(24): 3477-3480, 2019 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-30829356

RESUMO

For real-life CO2 capture, through the construction and fine tuning of the traps in metal-organic frameworks, we synthesized NJU-Bai51 with the combined features of high capacity, high selectivity and high water-stability, confirmed via breakthrough experiments, and its specific binding interaction was revealed from crystallographic measurements.

6.
Inorg Chem ; 58(4): 2729-2735, 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30702876

RESUMO

A new amide-functionalized metal-organic framework (AFMOF) with the combined feature of highly selective CO2 adsorption and high thermal and chemical stability, [Sc3(µ3-O)(L)1.5(H2O)3Cl] n [NJU-Bai49; NJU-Bai for Nanjing University Bai's group, H4L = 5-(3,5-dicarboxybenzamido)isophthalic acid], was synthesized that exhibits 4.5 wt % CO2 uptake at 298 K and 0.15 bar and the highest selectivity for CO2/N2 (166.7) among all AFMOFs. Grand canonical Monte Carlo simulations further indicate that both the decorated amide group and the open metal site act as CO2 binding sites, which may contribute to its highly selective CO2 uptake.

7.
J Am Chem Soc ; 140(51): 17825-17829, 2018 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-30223654

RESUMO

A new approach of finely tuning multinuclear clusters of metal-organic frameworks (MOFs) through symmetry-upgradingly isoreticular transformation was first presented and a bcu-type MOF, {[Cu4(µ4-O)Cl2(IN)4][CuCl2]}∞ (NJU-Bai35; NJU-Bai for Nanjing University Bai group), with cluster [Cu4(µ4-O)Cl2(COO)4N4] of higher symmetry compared to the pristine MOF, was successfully synthesized. The symmetry upgrading implemented on the inorganic part triggers the adjustment of channels in NJU-Bai35 to fit CO2 molecules, leading to a high CO2 adsorption capacity (7.20 wt % at ∼0.15 bar and 298 K) and high selectivity of CO2 over N2 and CH4 (275.8 for CO2/N2 and 11.6 for CO2/CH4) in NJU-Bai35. Breakthrough experiments further confirmed that NJU-Bai35 might be an excellent candidate for CO2 capture and natural gas purification.

8.
Angew Chem Int Ed Engl ; 56(38): 11426-11430, 2017 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-28707307

RESUMO

We present a crystal engineering strategy to fine tune the pore chemistry and CH4 -storage performance of a family of isomorphic MOFs based upon PCN-14. These MOFs exhibit similar pore size, pore surface, and surface area (around 3000 m2 g-1 ) and were prepared with the goal to enhance CH4 working capacity. [Cu2 (L2)(H2 O)2 ]n (NJU-Bai 41: NJU-Bai for Nanjing University Bai's group), [Cu2 (L3)(H2 O)2 ]n (NJU-Bai 42), and [Cu2 (L4)(DMF)2 ]n (NJU-Bai 43) were prepared and we observed that the CH4 volumetric working capacity and volumetric uptake values are influenced by subtle changes in structure and chemistry. In particular, the CH4 working capacity of NJU-Bai 43 reaches 198 cm3 (STP: 273.15 K, 1 atm) cm-3 at 298 K and 65 bar, which is amongst the highest reported for MOFs under these conditions and is much higher than the corresponding value for PCN-14 (157 cm3 (STP) cm-3 ).

9.
ACS Appl Mater Interfaces ; 8(46): 31746-31756, 2016 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-27933976

RESUMO

The combination of carbon dioxide capture and chemical fixation in a one-pot process is attractive for both chemists and governments. The cycloaddition of carbon dioxide with epoxides to produce cyclic carbonates is an atomic economical reaction without any side products. By incorporating acylamide to enhance the binding affinity toward CO2, new rht-type metal-organic frameworks (MOFs) with (3, 28) and (3, 24) connected units were constructed. Zn-NTTA with two types of dinuclear paddlewheel building blocks-{Zn2(OOC-)4} and {Zn2(OOC-)3}. The high uptake of CO2 (115.6 cm3·g-1) and selectivity over N2 (30:1) at 273 K indicated that these MOFs are excellent candidates for postcombustion CO2 isolation and capture. The MOFs feature high catalytic activity, rapid dynamics of transformation and excellent stability with turnover number (TON) values up to 110 000 per paddlewheel unit after 5 × 6 rounds of recyclability, demonstrating that they are promising heterogeneous catalysts for CO2 cyclo-addition to value-added cyclic carbonates. The cycloaddition of epoxides with wet gases demonstrated that the catalyst activity was not affected by moisture, and the indices of the PXRD patterns of the bulk samples filtered from the catalytic reaction revealed that the crystallinities were maintained. The combination of the selective capture and catalytic transformation in one-pot enables the use of a negative-cost feedstock-raw power plant flue gas without any separation and purification-revealing the broad prospects of such MOFs for practical CO2 fixation in industry.

10.
Inorg Chem ; 55(11): 5139-51, 2016 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-27168002

RESUMO

From a methyl-substituted thieno[2,3-b]thiophene dicarboxylate, three types of three-dimensional (3-D) microporous lanthanide-based metal-organic frameworks, {[Ln(DMTDC)1.5(H2O)2]·DEF}n (type I, Ln = Eu 1, Tb 2), {[Ln(DMTDC)1.5(H2O)2]·0.5DMF·0.5H2O}n (type II, Ln = Gd 3, Dy 4, Er 5), and {[Ln4(DMTDC)6(DMF)2]·0.5DMF·1.5H2O}n (type III, Ln = Er 6) (H2DMTDC = 3,4-dimethylthieno[2,3-b]thiophene-2,5-dicarboxylic acid, DEF = N,N'-diethylformamide, DMF = N,N'-dimethylformamide), have been solventhermally synthesized. Types I and II are isostructural, which exhibit 1-D triangular channels constructed by double-stranded rod-shaped {Ln(CO2)2}n chains. Type III demonstrates an intriguing framework with triple-stranded rod-shaped {Ln(CO2)3}n chains arranged along the (1,1,0) and (1,-1,0) axes and possesses two kinds of triangular channels along two axes, respectively. Immobilization of the Lewis basic sites of thiophene groups induced gas adsorption and sensing properties into these microporous frameworks. Complexes 5(Er) and 6(Er) display moderate adsorption properties toward N2 and CO2, and the Qst of CO2 are as high as 36.3 and 34.8 kJ mol(-1), respectively. Complexes 1(Eu) and 2(Tb) exhibit sensing properties toward nitrobenzene, acetone, and the Cu(2+) ion in both DMF and aqueous solution. Complex 3(Gd) shows a significant magnetocaloric effect with ΔSm = 24.3 J·kg(-1)·K(-1) at 3.0 K and 7 T. Complex 4(Dy) exhibits slow magnetic relaxation with the energy barrier Δ/kB of 48.29 K.

11.
Chem Commun (Camb) ; 52(45): 7241-4, 2016 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-27173153

RESUMO

Aiming to improve the acetylene (C2H2) storage capability of MOFs, we successfully designed NJU-Bai 17, a new analogue of MOF-505 with an inserted amide functional group which exhibits almost record high C2H2 uptakes of 222.4 cm(3) g(-1) at 296 K and 296 cm(3) g(-1) at 273 K under 1 bar. This result has been further supported by the determination of the heat of C2H2 adsorption and Grand Canonical Monte Carlo (GCMC) and first-principle calculations.

12.
Chemistry ; 22(18): 6277-85, 2016 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-27031809

RESUMO

A new stepwise ligand-elongation strategy by amide spacers is utilized to prepare isoreticularly high-porous metal-organic frameworks (MOFs), namely, quasi-mesoporous [Cu2 (PDBAD)(H2 O)]n (H4 PDBAD=5,5'-((4,4'-((pyridine-3,5-dicarbonyl)bis(azanediyl))bis(benzoyl))bis(azanediyl))diisophthalic acid; NJU-Bai22: NJU-Bai for Nanjing University Bai's group), and mesoporous [Cu2 (PABAD)(H2 O)]n (H4 PABAD=5,5'-((4,4'-((4,4'-((pyridine-3,5-dicarbonyl)bis(azanediyl))bis(benzoyl))bis (azanediyl))bis(benzoyl))bis(azanediyl))diisophthalic acid; NJU-Bai23). Compared with the prototypical MOF of [Cu2 (PDAD)(H2 O)]n (H4 PDAD=5,5'-(pyridine-3,5-dicarbonyl)bis(azanediyl)diisophthalic acid; NJU-Bai21, also termed as PCN-124), both MOFs exhibit almost the same CO2 adsorption enthalpy and CO2 selectivity values, and better capacity for CO2 storage under high pressure; these results make them promising candidate materials for CO2 capture and sequestration. Interestingly, this new method, in comparison with traditional strategies of using phenyl or triple-bond spacers, is easier and cheaper, resulting in a better ability to retain high CO2 affinity and selectivity in MOFs with large pores and high CO2 storage capacity. Additionally, it may lead to the high thermal stability of the MOFs and also their tolerance to water, which is related to the balance between the density of functional groups and pore sizes. Therefore, this strategy could provide new opportunities to explore more functionalized mesoporous MOFs with high performance.

13.
Water Res ; 98: 128-37, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27088247

RESUMO

A dual-function starch-based flocculant, carboxymethyl-starch-graft-aminomethylated-polyacrylamide (CMS-g-APAM), was designed and prepared by a simple method. The structure and solution properties of CMS-g-APAM were characterized by fourier transform infrared spectroscopy, (1)H nuclear magnetic resonance, and zeta-potential measurements. CMS-g-APAM was then applied to flocculate a kaolin suspension and an Escherichia coli suspension as well as a combination thereof. At suitable pH conditions, the starch-based flocculant not only effectively removed turbidity but it also disrupted bacterial cells. Interpretation of the zeta potential and floc properties (floc size and two-dimensional fractal structure) showed that, for the aforementioned three effluents, simple charge neutralization was the dominant mechanism of flocculation in acidic medium whereas an additional contribution from a patching effect was determined under neutral conditions. Three-dimensional excitation-emission matrix spectra and direct surface morphology observation under a scanning electron microscope both illuminated that the antibacterial activity of CMS-g-APAM involved the partial destruction of the cell wall of Escherichia coli. The mechanism can be attributed to the effective interaction between the tertiary amine group of the flocculant and the negatively charged surface of the bacterium.


Assuntos
Escherichia coli , Água , Floculação , Concentração de Íons de Hidrogênio , Amido/química
14.
Chem Commun (Camb) ; 52(3): 443-52, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26512792

RESUMO

CO2 capture science and technology, particularly for the post-combustion CO2 capture, has become one of very important research fields, due to great concern of global warming. Metal-organic frameworks (MOFs) with a unique feature of structural fine-tunability, unlike the traditional porous solid materials, can provide many and powerful platforms to explore high-performance adsorbents for post-combustion CO2 capture. Until now, several strategies for finely tuning MOF structures have been developed, in which either the larger quadrupole moment and polarizability of CO2 are considered: metal ion change (I), functional groups attachment (II) and functional group insertion (III), vary the electronic nature of the pore surface; or targeting the smaller kinetic diameter of CO2 over N2 is focused on: framework interpenetration (IV), ligand shortening (V) and coordination site shifting (VI) contract the pore size of frameworks to improve their CO2 capture properties. In this review, from the viewpoint of synthetic materials scientists/chemists, we would like to introduce and summarize these strategies based upon recent work published by other groups and ourselves.

15.
Angew Chem Int Ed Engl ; 52(43): 11282-5, 2013 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-24027078

RESUMO

Breaking edges off regular truncated cuboctahedra leads to a metal-organic framework (MOF) with polybenzene topology. This fully characterized MOF with lowest connectivity has the largest BET surface area among interpenetrated MOFs.

16.
Inorg Chem ; 52(6): 2823-9, 2013 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-23458072

RESUMO

An expanded 4,4-paddlewheel-connected porous MOF-505-type metal-organic framework (MOF), [Cu2(PDEB)(H2O)2]·xS (NJU-Bai12; NJU-Bai represents the Nanjing University Bai group and S represents noncoordinated solvent molecules) has been designed from a nanosized rectangular diisophthalate linker containing alkyne groups 5,5'-(1,4-phenylenedi-2,1-ethynediyl)bis(1,3-benzenecarboxylic acid). This MOF material possesses permanent microporosity with the highest Brunauer-Emmett-Teller surface area of 3038 m(2)·g(-1) and the largest unsaturated total hydrogen storage capacity of 62.7 mg·g(-1) at 77 K and 20 bar among reported MOF-505 analogues. Additionally, NJU-Bai12 also exhibits excellent carbon dioxide (CO2) uptake capacity (23.83 and 19.85 mmol·g(-1) at 20 bar for 273 and 298 K, respectively) and selective gas adsorption properties with CO2/CH4 selectivity of 5.0 and CO2/N2 selectivity of 24.6 at room temperature.

17.
J Am Chem Soc ; 135(2): 562-5, 2013 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-23268731

RESUMO

Based upon the (3,6)-connected metal-organic framework {Cu(L1)·2H(2)O·1.5DMF}(∞) (L1 = 5-(pyridin-4-yl)isophthalic acid) (SYSU, for Sun Yat-Sen University), iso-reticular {Cu(L2)·DMF}(∞) (L2 = 5-(pyridin-3-yl)isophthalic acid) (NJU-Bai7; NJU-Bai for Nanjing University Bai group) and {Cu(L3)·DMF·H(2)O}(∞) (L3 = 5-(pyrimidin-5-yl)isophthalic acid) (NJU-Bai8) were designed by shifting the coordination sites of ligands to fine-tune pore size and polarizing the inner surface with uncoordinated nitrogen atoms, respectively, with almost no changes in surface area or porosity. Compared with those of the prototype SYSU, both the adsorption enthalpy and selectivity of CO(2) for NJU-Bai7 and NJU-Bai8 have been greatly enhanced, which makes NJU-Bai7 and NJU-Bai8 good candidates for postcombustion CO(2) capture. Notably, the CO(2) adsorption enthalpy of NJU-Bai7 is the highest reported so far among the MOFs without any polarizing functional groups or open metal sites. Meanwhile, NJU-Bai8 exhibits high uptake of CO(2) and good CO(2)/CH(4) selectivity at high pressure, which are quite valuable characteristics in the purification of natural gases.

18.
Inorg Chem ; 51(13): 7066-74, 2012 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-22708831

RESUMO

Three porous supramolecular isomers (IZE-1, IZE-2, and IZE-3) with the same framework component [Zn(2)(EBTC)(H(2)O)(2)] (EBTC = 1,1'-ethynebenzene-3,3',5,5'-tetracarboxylate) were successfully constructed by finely tuning the reaction condition. Although both IZE-1 and IZE-2 are constructed from the linear EBTC subunits and one kind of regular [Zn(2)(CO(2))(4)] paddlewheels, their frameworks exhibit two different (3,4)-c net of fof (sqc1575) and sqc1572, respectively, resulting in cavities with different size and shape. However, as for isomer IZE-3, the EBTC ligands are bent and one-half of the [Zn(2)(CO(2))(4)] paddlewheels are distorted, leading to a novel (3,4,4)-c hyx net with point symbol (6.7(2))(4)(6(2).8(2).10(2))(7(2).8(2).11(2)) and vertex symbol (6.7.7)(4)(7(2).7(2).8.8.12.12)(6.6.8.8.10(2).10(2)). Quantum chemical calculations by DFT indicate that the three isomers have very close thermodynamic stabilities, which may explain that subtle condition change leads to variation of the frameworks. Further theoretical semiempirical investigation on the interactions between solvent molecules and compounds shows different hydrogen binding patterns in good agreement with the experimental observations. Furthermore, they exhibit good solid-state luminescence properties with long lifetime.


Assuntos
Compostos Organometálicos/química , Zinco/química , Cristalografia por Raios X , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química , Porosidade , Teoria Quântica , Estereoisomerismo
19.
Chem Commun (Camb) ; 48(56): 7025-7, 2012 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-22314412

RESUMO

Two mesoporous and flexible acylamide-functionalized rht-type MOFs exhibit not only high excess unsaturation CO(2) uptake (157 wt%) at 20 bar and 273 K, but also good selectivity of CO(2)/CH(4) (8.6) and CO(2)/N(2) (34.3). The advantages of acylamide groups for CO(2) capture have been further confirmed by GCMC and first-principles calculations.


Assuntos
Amidas/química , Dióxido de Carbono/química , Compostos Organometálicos/química , Modelos Moleculares , Estrutura Molecular , Porosidade , Propriedades de Superfície
20.
Chem Commun (Camb) ; 48(25): 3058-60, 2012 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-22222221

RESUMO

An amide-inserted metal-organic framework (NJU-Bai3) presents high storage and high selectivity toward CO(2) and combines these two interesting characters which strongly support our expectation that amide groups can significantly enhance the CO(2) binding ability and selectivity of MOFs.

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