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1.
Dig Dis Sci ; 69(1): 45-55, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36920668

RESUMO

BACKGROUND: Early initiation of biologics in moderate-to-severe Crohn's disease (CD) may significantly alter disease progression, resulting in better patient outcomes. Limited real-world data exist on the impact of early biologic use in patients with CD in the United States. AIMS: We aimed to characterize biologic initiation and subsequent healthcare resource utilization (HCRU) in adults with recently diagnosed CD. METHODS: Patients with CD who initiated biologic treatment within 2 years of diagnosis (index date) were identified from medical and pharmacy claims (Merative L.P. MarketScan Database from 2010 to 2016) and classified as early (≤ 12 months post-index) or late (> 12-24 months post-index) biologic initiators. Propensity score matching balanced patient characteristics up to 1 year post-index. Differences in HCRU frequency and costs 1-2 years post-index were compared between the matched groups. RESULTS: After propensity score matching, 672 pairs of early and late biologic initiators were identified. Patients who initiated biologics early had fewer outpatient visits (15.5 vs 19.8, 95% confidence interval [CI] for difference: 2.7, 6.1) and lower total medical costs ($13,646.20 vs $22,180.70, 95% CI for difference: 4748.9, 12,320.1) 1-2 years post-index than late biologic initiators. Early biologic initiators had higher medication costs 1-2 years post-index ($33,766.30 vs $30,580.70, 95% CI: 546.1, 5825.1) but lower combined medical and medication costs ($47,412.50 vs $52,761.50, 95% CI: 801.5, 9896.40). CONCLUSIONS: While biologic treatments are costly, patients initiating biologics sooner after diagnosis appear to have better HCRU outcomes and require fewer healthcare resources at 1-2 years post-index, potentially leading to overall cost savings.


Assuntos
Produtos Biológicos , Doença de Crohn , Adulto , Humanos , Estados Unidos , Doença de Crohn/diagnóstico , Doença de Crohn/tratamento farmacológico , Estudos Retrospectivos , Custos de Cuidados de Saúde , Custos de Medicamentos , Produtos Biológicos/uso terapêutico
2.
J Hazard Mater ; 441: 129852, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36063715

RESUMO

The development of superhydrophobic adsorbents for the capture of trace volatile organic compounds (VOCs) from humid indoor air is still a challenge. Herein, we reported the formation of a granular zinc-based metal-organic gel, i.e., ZIF-412(gel) by optimizing the synthesis conditions. The thermally stable xerogel exhibited high surface area (1008 m2/g), hydrophobicity, and viscosity for self-depositing on the substrate such as non-woven fibers. Dynamic adsorption experiments under various humidity conditions demonstrated as-synthesized ZIF-412(gel) owned excellent VOC (hexanal) adsorption performance with adsorption capacity higher than commercial activated carbon and some water-stable MOFs including ZIF-8, ZIF-67, MIL-101(Cr) and ZIF-414. ZIF-412(gel) could be regenerated at temperature as low as 358 K without obvious loss in adsorption capacity. The adsorption mechanism of hexanal over ZIF-412(gel) is also simulated by Grand canonical Monte Carlo (GCMC).

3.
J Hazard Mater ; 442: 129998, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36152540

RESUMO

The removal and recovery of volatile organic compounds (VOCs) are widely used in many industrials. Unfortunately, most conventional porous materials not only have low VOCs uptake, but also need to be regenerated at relatively high temperature. Metal-organic frameworks (MOFs) have great potential for the removal and recovery of VOCs as their record-breaking gas adsorption capacity, easy regeneration, tunable pore structure and functional groups. Whereas, powdered MOFs are hardly implemented in industrial fields owing to their low bulk density and high pressure drop. Exploring a green method to prepare granular MOFs for the removal and recovery of VOCs is still a challenge. Herein, we report the room temperature green synthesis of a stable Fe-based MOF monolith by using water as the solvent without applying high pressure and chemical binders. The static and dynamic experiments show that the optimized centimeter-scale monolith has high porosity and mechanical strength, and exhibits much better adsorption performance for representative aromatic VOCs (benzene, toluene and p-xylene), than commercial activated carbon and activated carbon fiber under the same conditions. Remarkably, as-synthesized monolith can be rapidly regenerated at lower temperature. These results clearly demonstrate the advantages of MOF monoliths in removing and recovering VOCs, and also provide new insight into the effects of drying temperature, washing and centrifugation procedures on MOF shaping.

4.
ACS Appl Mater Interfaces ; 13(15): 17543-17553, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33845577

RESUMO

Porous carbon materials with chemical and thermal stability and high porosity have been widely used for volatile organic compound (VOC) purification. Designing granular carbon with remarkable adsorption capacity and rapid regeneration is of great significance for the capture of VOCs from high humidity air. Herein, a series of N-doped granular carbons were synthesized by direct carbonization of metal-organic gel (MOG). The N-doped granular carbons (C700 and C700K) feature high surface area, hierarchical pore, and abundant N,O multifunctional groups. The toluene adsorption capacity of C700K is highly improved (9.0 mmol/g toluene at P/P0 = 0.1) in comparison with MOG (4.81 mmol/g toluene at P/P0 = 0.1). The toluene breakthrough time of C700K is over 4 times longer than that of MOG at wet conditions (60% RH, 298 K), also much longer than that of widely used carbon materials, zeolites, and representative MOFs, including BPL activated carbon, coconut shell activated carbon, carbosieve, ZSM-5, and MIL-101(Cr). Furthermore, the N-doped granular carbons also exhibit excellent hydrophobicity and can be regenerated rapidly. The internal pore channel and desorption kinetics reveal that the effective diffusion length plays a critical role in the regeneration rate.

5.
J Hazard Mater ; 411: 125034, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-33858080

RESUMO

Carbon frameworks (CFs) derived from metal-organic frameworks (MOFs) have been produced as adsorbents of toluene. To further obtain optimum hierarchical porous carbon structure of CFs, different treatment temperatures were applied to a typical kind of MOFs (ZIF-8). The adsorption capacity of the toluene of hierarchical porous CFs obtained from ZIF-8 under 1100 °C (CF-1100, adsorption capacity of 208.5 mg/g) was higher than that of other carbonization temperature and MOFs. Impressively, the adsorbent CF-1100 also exhibited strong hydrophobicity, low desorption temperature, and good selectivity to toluene. The adsorption capacity decreased by only 10.4% under wet condition compared with the dry condition, standing on the top of the recently reported adsorbents. The impressive adsorption performance of CF-1100 is attributed to the larger specific surface area (1024 m2/g) and pore volume (0.497 cm3/g), newly generated micropores (pore width is 0.6-0.8 nm) and mesopores (pore width above 10 nm), and carbonaceous structure with higher degree of graphitization. Based on the adequate adsorption performance, CF-1100 coated quartz crystal microbalances as sensor also showed a high sensitivity of 0.4004 Hz/ppm and small relative standard deviations of 1.0745% for toluene sensing. This contribution provides a foundation for optimizing potential adsorbents and sensing materials for air pollution abatement.

6.
ACS Appl Mater Interfaces ; 13(15): 17532-17542, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33826288

RESUMO

Room-temperature catalytic decomposition of low-concentration volatile organic compounds (VOCs) in indoor air is an exciting dream to solve their pollution. Herein, two kinds of rare-earth elements (Y and La) were separately doped into birnessite-type MnO2 nanosheets in the form of single atoms by the hydrothermal method. As-synthesized La/MnO2 achieved 100% removal of 10 ppm toluene at 40 °C under the gas hourly space velocity of 60 L g-1 h-1, which was even somewhat better than the single Pt atom-doped MnO2. In addition, La/MnO2 showed the good durability at room temperature for 0.5 ppm toluene removal under the GHSV of 300 L g-1 h-1 and could be effectively regenerated at 105 °C. GC/FID, online-MS and TD-GC/MS analysis demonstrated that only ignorable trace benzene (∼3.4 ppb, < one thousandth of inlet toluene) was generated in the gas phase during catalytic decomposition of 10 ppm toluene at room temperature. This research sheds light on the development of low cost and high activity catalysts for low-concentration VOC oxidation at room temperature.

7.
J Hazard Mater ; 411: 125057, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-33465540

RESUMO

The discovery of granular adsorbents for the capture of volatile organic compounds (VOCs) from humid air and rapid regeneration at low temperature is still a challenge. Here we reported formation of a granular Al-based metal organic gel, CAU-3-NH2(gel), by adjusting heating up time in the synthesis procedure. The water and thermal stable xerogel shows high surface area (1964 m2/g) and adsorption capacity for VOCs (uptakes of toluene and hexanal reach 4.5 and 3.85 mmol/g at P/P0 = 0.1, respectively). Dynamic adsorption experiments further conformed its outstanding adsorption performance for toluene under 50% RH, higher than that of commercial adsorbents and widely studied MOFs including BPL activated carbon, ZSM-5, zeolite 13X, XAD-16, MIL-101(Cr), CAU-1 and ZIF-8. Under the mass space velocity of 12,000 mL/g.h, CAU-3-NH2(gel) kept 99.95% removal ratio of low concentration toluene (100 ppm) over 12 h in 3 cycles at 298 K. Furthermore, desorption experiments show its excellent regenerability under mild temperature (328 K and 358 K). The interaction of toluene-framework and adsorption process are investigated by using Grand Canonical Monte Carlo (GCMC) simulations.

8.
J Hazard Mater ; 408: 124917, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33370692

RESUMO

Heavy metals are seriously hazardous contaminants and drinking water has been identified as an important route of human exposure to them. Herein, to efficiently and selectively remove trace heavy metal ions, a facile method was reported to achieve the slow polymerization of dopamine in the cages of MIL-100 (Fe) via ultrasonic treatment followed by the hydrolysis of the urea. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), Brunner-Emmet-Teller (BET) and pore size distribution determination confirmed the formation of the polydopamine (PDA) and binding with the unsaturated Fe3+ site in MIL-100 (Fe) pores. The composite not only retained pore structure of MOFs but also contained abundant reactive functional groups. When initial lead concentration was 150 ppb and 20 ppm calcium coexisted at pH of 6.5 ± 0.25, the effluent lead concentration met the safe drinking water standard in several tens of seconds, and decreased to 1.13 ppb in 10 min. The adsorption rate reached 99.35%. The synthetic strategy effectively overcomes mass transfer resistance of trace heavy metal ions and provides a facile approach to prepare adsorption materials for efficient and selective removal of trace heavy metal ions from drinking water.

9.
ACS Appl Mater Interfaces ; 12(37): 41359-41367, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32808763

RESUMO

Exploring a synthesis method for preparing hydrophobic metal-organic gels (MOGs) is highly desirable for air purification. Here, we present a rapid heating-up synthetic route to hydrophobic MOG denoted CAU-3(gel) with hierarchical micro/mesoporosity. CAU-3(gel), which features water and thermal stability, high surface area, and hydrophobicity, exhibits excellent performance for the capture of three representative volatile organic compounds (hexanal, toluene, and p-xylene), higher than BPL activated carbon, zeolite 13X, and some representative metal-organic frameworks including ZIF-8, HKUST-1, MIL-101(Cr), and UiO-66 under wet conditions. Furthermore, CAU-3(gel) could be easily coated on a nonwoven fabric by a simple dip-coating method without using any binder, which exhibits outstanding hexanal removal performance and regenerability at low temperature. Grand canonical Monte Carlo simulations show that hexanal preferentially enters relatively small tetrahedral cages and occupies two adsorption sites at low pressure and then a new site appears in octahedral cages with increasing pressure.

10.
Chemosphere ; 203: 271-280, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29625316

RESUMO

The increasing nuclear energy consumption has posed serious environmental concerns (e.g. nuclear leakage), and the removal of radionuclides such as cesium becomes an urgent issue to be solved currently. In this research, a novel non-toxic adsorbent lithium-modified montmorillonite clay encapsulated in calcium alginate microbeads (MCA/Li) was fabricated by using ion-exchange method and then used successfully in the remediation of cesium-contaminated wastewater. Analyses of scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy were used to characterize the physicochemical properties of adsorbent MCA/Li, such as internal crystal structure, constituent elements, and functional groups. The effects of concentration ratios (sodium alginate/montmorillonite), solution pH, contacting time and initial Cs+ concentration on the adsorption behavior were carefully investigated via batch adsorption experiments. The adsorbent MCA/Li exhibited higher selectivity and removal efficiency towards Cs+ with the maximum adsorption capacity of 100.25 mg/g. In the kinetics study, the pseudo-first-order fitted the cesium adsorption data of MCA/Li better than the pseudo-second-order. The adsorption mechanism studies revealed the process followed the Langmuir isotherm model, which suggested that Cs+ adsorption onto MCA/Li is a monolayer homogeneous adsorption process. The research findings indicated this novel adsorbent MCA/Li demonstrated great potential in radioactive wastewater treatment due to its convenience in synthesis, high adsorption capacity, and low cost.


Assuntos
Alginatos/química , Bentonita/química , Césio/química , Recuperação e Remediação Ambiental/métodos , Radioisótopos/química , Águas Residuárias/química , Poluentes Químicos da Água/química , Adsorção , Césio/análise , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Concentração de Íons de Hidrogênio , Íons , Lítio/química , Radioisótopos/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise , Difração de Raios X
11.
J Environ Sci (China) ; 56: 12-24, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28571846

RESUMO

To remove cesium ions from water and soil, a novel adsorbent was synthesized by following a one-step co-precipitation method and using non-toxic raw materials. By combining ammonium-pillared montmorillonite (MMT) and magnetic nanoparticles (Fe3O4), an MMT/Fe3O4 composite was prepared and characterized. The adsorbent exhibited high selectivity of Cs+ and could be rapidly separated from the mixed solution under an external magnetic field. Above all, the adsorbent had high removal efficiency in cesium-contaminated samples (water and soil) and also showed good recycling performance, indicating that the MMT/Fe3O4 composite could be widely applied to the remediation of cesium-contaminated environments. It was observed that the pH, solid/liquid ratio and initial concentration affected adsorption capacity. In the presence of coexisting ions, the adsorption capacity decreased in the order of Ca2+>Mg2+>K+>Na+, which is consistent with our theoretical prediction. The adsorption behavior of this new adsorbent could be expressed by the pseudo-second-order model and Freundlich isotherm. In addition, the adsorption mechanism of Cs+ was NH4+ ion exchange and surface hydroxyl group coordination, with the former being more predominant.


Assuntos
Compostos de Amônio/química , Césio/análise , Poluentes Químicos da Água/análise , Adsorção , Bentonita/química , Césio/química , Precipitação Química , Concentração de Íons de Hidrogênio , Cinética , Solo/química , Água/química , Purificação da Água/métodos
12.
Carbohydr Polym ; 167: 306-316, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28433167

RESUMO

Novel and magnetic adsorbent ammonium-pillared montmorillonite-CoFe2O4 composite caged in calcium alginate beads was prepared by using non-toxic raw materials. The morphology, magnetic properties, functional groups, and crystal structure of the compound were characterized by SEM, VSM, FT-IR and XRD. The adsorption behaviors were also investigated via adsorption experiments and response surface methodology was used to optimize the operation conditions. The beads showed high selectivity for Cs+ in the presence of Na+ and could be rapidly separated from the mixed solution under an external magnetic field. The maximum adsorption capacity was 86.46mg/g, which is higher than that of previously reported magnetic adsorbents. The adsorption kinetics and adsorption isotherms could be expressed by the pseudo-second-order and Langmuir isotherm, respectively. The relationship between a dependent variable (i.e., removal efficiency or adsorption capacity) and an independent variable (i.e., initial concentration, contact time, and adsorbent dosage) could be fitted to a quadratic second-order polynomial equation. The adsorption mechanism primarily involved ion exchange while coordination reactions also contributed.

13.
Bioorg Med Chem Lett ; 19(7): 1861-5, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19272773

RESUMO

A series of caffeic acid amide derivatives 2-cyano-(3-substituted phenyl)acrylamides were synthesized via Knoevenogal condensation of substituted benzaldehydes with cyanoacetamides. The structure of compound 1f was determined as E-isomer by X-ray diffractive analysis. The biological screening tests in vitro showed that compound 1b has obvious inhibitory activities against human gastric carcinoma cell line BGC-823, human nasopharyngeal carcinoma cell line KB and human hepatoma cell line BEL-7402 with IC(50) values of 5.6 microg/mL, 13.1 microg/mL and 12.5 microg/mL, respectively. Some preliminary structure-activity relationships (SAR) were also proposed which may provide a direction for further study.


Assuntos
Acrilamidas/síntese química , Acrilamidas/farmacologia , Ácidos Cafeicos/química , Nitrilas/síntese química , Nitrilas/farmacologia , Acrilamidas/química , Linhagem Celular Tumoral , Cristalografia por Raios X , Humanos , Concentração Inibidora 50 , Nitrilas/química , Relação Estrutura-Atividade
14.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 10): o2351, 2009 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-21577820

RESUMO

The title compound, C(12)H(10)N(2)O(6), was synthesized via a Knoevenagel condensation and crystallized from ethanol. In the crystal, strong classical inter-molecular O-H⋯O hydrogen bonds and weak C-H⋯N contacts link the mol-ecules into ribbons extending along [010]. Intra-molecular O-H⋯O and C-H⋯N contacts support the planar conformation of the mol-ecules (mean deivation 0.0270 Å).

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