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1.
Nanotechnology ; 34(24)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36898149

RESUMO

A particular bird's nest-like pseudo-boehmite (PB) composed of cohesive nanostrips was prepared by a novel and facile approach based on the reaction of Al-Ga-In-Sn alloy and water, together with ammonium carbonate. The PB possesses a large specific surface area (465.2 m2g-1), pore volume (1.0 cm3g-1), and pore diameter (8.7 nm). Subsequently, it was utilized as a precursor to form the TiO2/γ-Al2O3nanocomposite for tetracycline hydrochloride removal. The removal efficiency can reach above 90% at TiO2:PB = 1:1.5 under the Sunlight irradiation simulated by a LED lamp. Our results indicate that the nest-like PB is a promising carrier precursor for efficient nanocomposite catalysts.

2.
Chemistry ; 27(41): 10666-10676, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34009699

RESUMO

A highly efficient heterogeneous catalyst Pd/Mg2 P2 O7 was fabricated by combining palladium nanoparticles (PdNPs) and mesoporous Mg2 P2 O7 fibers/rods. Mg2 P2 O7 fibers with ultra-high specific surface area were prepared from struvite as templates, which were synthesized from waste water containing N- and P-containing pollutants. This strategy provided a novel pathway for developing advanced catalysts from eutrophication-polluted water. The composite Pd/Mg2 P2 O7 showed brilliant performance in selective hydrogenation of nitro aromatics to give anilines. As an example of nitrobenzene hydrogenation, the conversion to aniline and selectivity were found to reach almost 100 % at a temperature of T=90 °C and under a pressure of P H 2 =2.0 MPa. The superior performance was found to originate from PdNPs, which were boosted by electron transfer afforded by the nanofiber Mg2 P2 O7 supports. The favorable adsorption of withdrawing groups (-NO2 ) was realized by synergistic effects between Pd and oxygen vacancies provided by pyrolysis of struvite. The catalyst remained stable after cycles of reuse with little degradation in catalytic performance.

3.
Molecules ; 26(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34500641

RESUMO

A novel diatomite-supported zeolitic imidazolate framework-8 sorbent (ZIF-8@Dt-COOH) was in situ fabricated and developed for solid-phase extraction of three benzodiazepines (triazolam, midazolam and diazepam) in urine followed by high-performance liquid chromatography. ZIF-8@Dt-COOH was easily prepared by coating ZIF-8 on the surface of Dt-COOH and characterized by Fourier transform infrared spectra, X-ray powder diffractometry and scanning electron microscopy. Compared with bare Dt-COOH, the extraction efficiency of ZIF-8@Dt-COOH for the target was significantly increased from 20.1-39.0% to 100%. Main extraction parameters, including ionic strength and pH of solution, loading volume, washing solution, elution solvent and elution volume, were optimized in detail. Under optimum conditions, the developed method gave linearity of three BZDs in 2-500 ng/mL (r ≥ 0.9995). Limits of detection (S/N = 3), and limits of quantification (S/N = 10) were 0.3-0.4 ng/mL and 1.0-1.3 ng/mL, respectively. In addition, the average recoveries at three spiked levels (5, 10 and 20 ng/mL) varied from 80.0% to 98.7%, with the intra-day and inter-day precisions of 1.4-5.2% and 1.5-8.2%, respectively. The proposed method provided an effective purification performance and gave the enrichment factors of 24.0-29.6. The proposed method was successfully employed for the accurate and sensitive determination of benzodiazepines in urine.


Assuntos
Benzodiazepinas/urina , Terra de Diatomáceas/química , Urina/química , Zeolitas/química , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Limite de Detecção , Extração em Fase Sólida/métodos , Soluções/química , Solventes/química
4.
J Clin Densitom ; 18(2): 198-202, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25937308

RESUMO

The aim of the study was to investigate the association between duration of playing video games and bone mineral density (BMD) in Chinese adolescents. Three hundred eighty-four Chinese adolescents aged 14-18 yr (148 males and 236 females) were analyzed. Anthropometric measurements were obtained using standard procedures. Total body and regional BMD were measured using dual-energy X-ray absorptiometry. Duration of playing video games, defined as hours per day, was measured by a self-report questionnaire. We examined the association between duration of playing video games and BMD using multiple linear regression analysis. After adjustment for age, sex, pubertal stage, parental education, body mass index, adolescents with longer video game duration were more likely to have lower legs, trunk, pelvic, spine, and total BMD (p < 0.05). We concluded that duration of video game was negatively associated with BMD in Chinese adolescents. These findings provide support for reducing duration of playing video games as a possible means to increase BMD in adolescents. Future research is needed to elucidate the underlined mechanisms linking playing video games and osteoporosis.


Assuntos
Densidade Óssea , Osso e Ossos/diagnóstico por imagem , Atividade Motora , Jogos de Vídeo/estatística & dados numéricos , Absorciometria de Fóton , Adolescente , China , Feminino , Humanos , Masculino , Ossos Pélvicos/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem , Inquéritos e Questionários , Tíbia/diagnóstico por imagem , Fatores de Tempo
5.
J Clin Densitom ; 18(1): 44-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24815308

RESUMO

The purpose of the study was to investigate the associations of fat mass (FM) and fat distribution with bone mineral density (BMD) in Chinese obese population. Three hundred and forty-seven Chinese obese females and 339 males aged 20-39 years were analyzed. Lean mass (LM), FM, percent body fat (%BF), android FM, gynoid FM, and total and regional BMD were measured using dual-energy X-ray absorptiometry. Fat distribution was assessed by android-to-gynoid FM ratio (AOI). As a result, increased central body fat had an inverse association with total and leg BMD in females but not in males. Increased FM and %BF were positively associated with arm, trunk, and pelvic BMD in Chinese obese females. Increased FM was positively associated with total, rib, and trunk BMD in Chinese obese males. The results remained almost unchanged after adjusting for LM, and LM was significantly positively associated with spine BMD in female group. FM was positively associated with trunk BMD in male group after adjusting for LM. AOI was inversely associated with total and leg BMD, and %BF was positively associated with arm, trunk, and pelvic BMD when replacing FM with %BF in female group. The results remained almost unchanged after adjusting for LM. There is no significant association in male group when replacing FM with %BF. In conclusion, our findings demonstrate that there are different associations of FM and fat distribution with BMD, and AOI has a negative association with BMD.


Assuntos
Densidade Óssea , Obesidade , Osteoporose , Absorciometria de Fóton/métodos , Tecido Adiposo/metabolismo , Adulto , Distribuição da Gordura Corporal/métodos , Osso e Ossos/diagnóstico por imagem , China/epidemiologia , Feminino , Humanos , Masculino , Obesidade/complicações , Obesidade/epidemiologia , Obesidade/metabolismo , Osteoporose/diagnóstico , Osteoporose/epidemiologia , Osteoporose/etiologia , Osteoporose/metabolismo , Fatores de Risco , Estatística como Assunto
6.
ACS Omega ; 7(23): 19775-19783, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35722006

RESUMO

The Al sheets alloyed by Ga-In-Sn are generally utilized to react with water for H2 production, while the valuable byproducts, i.e., alumina hydrates, have not been fully studied. In this work, through controlling the reaction temperature, three types of alumina hydrates, bayerite (40 °C), pseudo-boehmite (PB) (70-120 °C), and boehmite (130-160 °C), were successfully prepared based on a series of interface reactions and structural transformations. These alumina hydrates and their calcined products (alumina) possess high purity with a total impurity element content of <450 ppm, especially an extremely low sodium content (<21 ppm) and iron content (<52 ppm). Significantly, the obtained pseudo-boehmite displays excellent surface properties (specific surface area: 332.7 m2 g-1, pore volume: 0.3 cm3 g-1, and pore diameter: 3.6 nm), competitive to the current commercial SB powder by Sasol. This work not only deepens the understanding of the byproducts in a Ga-In-Sn-alloyed Al-water reaction but also establishes a facile "green" method oriented to industrial applications, which is promising for the linkage benefits of the hydrogen production industry.

7.
Polymers (Basel) ; 14(20)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36298005

RESUMO

Coal gasification fine slag (CFS) is a solid contaminant produced by an entrained flow gasifier, which pollutes fields and the air in the long term. CFS is a potential polymer reinforcement filler and has been used in polypropylene and acrylonitrile butadiene styrene resins. Coal gasification fine slag mesoporous silica (FS-SiO2) was prepared by acid leaching, calcination, and pH adjustment, with a larger specific surface area and less surface hydroxyl compared to the commercial precipitated silica (P-silica). The cure characteristics, crosslink density, mechanical properties, the morphology of the tensile fractures, dynamic mechanics, and rubber processing of the prepared styrene butadiene rubber (SBR) composites filled with P-silica and FS-SiO2 were analyzed, respectively. The results indicated that FS-SiO2 was dispersed more uniformly in the SBR matrix than P-silica owing to its smaller amount of surface hydroxyl and spherical structure, resulting in a better mechanical performance and wet skid resistance. In particular, the SBR composites with a filler pH of 6.3 exhibited the highest crosslink density and tensile strength, being superior to commercial P-silica. Significantly, the curing time decreased with the increase in the pH of FS-SiO2, which caused the rubber processing to be more efficient. This strategy can reduce the cost of rubber composites and the environmental pollution caused by CFS.

8.
Heliyon ; 5(12): e02999, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31872137

RESUMO

Although the surface organic modification of smectite has been investigated widely, the swelling behavior of clays has been scarcely studied with consideration of civil engineering applications. In this work a facile strategy of liquid-immersion (dilute H2SO4 aqeuous solution) was proposed, and the 3-aminopropyltrimethoxysilane (APS) was utilized as surface modifier to suppress expansibility of black cotton soil (BCS) which is a type of highly swelling soils in tropical areas. Factors such as the incorporation dosage of APS, surface characters of soil treated by solution of H2SO4 or Na2CO3, and reaction temperatures/time were investigated to get lower swelling ratios. The treatment of BCS by H2SO4 was found more effective in immobilizing APS molecules, and hydronium ions were suppressed after the APS modification. The free swelling index (FSI) of BCS was decreased from 120% to 15% after treatment with H2SO4 and appropriate amount of APS modification. The reaction can be completed within several hours at the room temperature to ~80 °C. The soil samples were characterized by different means including the X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscope, thermogravimetric analysis and Zeta potential measurements. The APS molecules were found to react with -OH groups of the clay, and the hydrophobic groups provide surface hydrophobicity, which prevents hydration of cations within clay minerals. The APS was indicated to re-constructed lamellar structures of smectites after H2SO4 treatment, which suppressed the intra-crystalline and the subsequent osmotic swelling. This research highlights the liquid immersion and surface modification is applicable in diminishing swelling ratios of highly expansive black cotton soil.

9.
Turk Neurosurg ; 27(3): 460-463, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27438611

RESUMO

Kyphoplasty is a minimal invasive technique with a low rate of complications. To the best of our knowledge, perforation of gastric wall following kyphoplasty has not been described yet. We present a case that was operated for radical resection of esophageal carcinoma eleven years ago and who underwent kyphoplasty after a recent sixth and seventh thoracic vertebral fracture was diagnosed. Afterwards, the patient complained of dysphagia and fever. His laboratory results showed signs of inflammation. Gastroscopy showed a foreign body in the stomach. Plain radiography, computed tomography scan and positron emission computed tomography confirmed the diagnosis of perforation of the gastric wall by polymethylmethacrylate. Despite adequate antibiotic treatment, the patient died from septic multiple organ failure. Indication for kyphoplasty in patients with any history of thoracic surgery should be scrutinized rigorously. Although this kind of complication may be relatively rare, awareness of this condition will improve our response to avoid any delay in making the correct diagnosis and providing specific treatment.


Assuntos
Cimentos Ósseos/efeitos adversos , Cifoplastia/efeitos adversos , Polimetil Metacrilato/efeitos adversos , Estômago/diagnóstico por imagem , Estômago/lesões , Idoso , Evolução Fatal , Humanos , Masculino , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia , Estômago/efeitos dos fármacos , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/cirurgia , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
10.
Oncol Lett ; 11(3): 2075-2083, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26998125

RESUMO

Anterior gradient protein 2 (AGR2) has been reported as a novel biomarker with a potential oncogenic role. However, its association with the prognosis and survival rate of gastric cancer (GC) has not yet been determined. Therefore, the present study aimed to examine the expression and prognostic significance of AGR2 in patients with GC. Immunohistochemistry was used to analyze AGR2 and cathepsin D (CTSD) protein expression in 436 clinicopathologically characterized GC cases and 92 noncancerous tissue samples. AGR2 and CTSD expression were both elevated in GC lesions compared with noncancerous tissues. In 204/436 (46.8%) GC patients, high expression of AGR2 was positively correlated with the expression of CTSD (r=0.577, P<0.01). Furthermore, several clinicopathological parameters were significantly associated with AGR2 expression level, including tumor size, depth of invasion and TNM stage (P<0.05). Using Kaplan-Meier survival analysis, it was determined that the mean survival time of patients with low levels of AGR2 expression was significantly longer than those with high ARG2 expression (in stages I, II and III; P<0.05). For stage IV disease, no significant difference in survival time was identified. Multivariate survival analysis demonstrated that AGR2 was an independent prognostic factor and was associated in the progression of GC. The findings of the present study indicate that AGR2 expression is significantly associated with location and size of GC, depth of invasion, TNM stage, lymphatic metastasis, vessel invasion, distant metastasis, Lauren's classification, high CTSD expression and poor prognosis. Thus, AGR2 may be a novel GC marker and may present a potential therapeutic target for GC.

11.
J Orthop Surg Res ; 10: 148, 2015 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-26381236

RESUMO

BACKGROUND: Zero-profile implant has become more and more popular in anterior cervical discectomy and fusion (ACDF) for the treatment of degenerative cervical spondylosis. However, there was no enough evidence judging its efficiency and safety. The aim of this analysis was to evaluate the efficacy and safety of Zero-profile implant compared with conventional cage-plate (CCP) in ACDF. METHODS: All studies directly comparing the outcomes between the Zero-profile implant and CCP implant in ACDF were included, and the search strategy followed the requirements of the Cochrane Library Handbook. Two of the authors extracted relevant data and checked the accuracy independently using standardized data collection form. RESULTS: Seven studies involving 560 patients were included, 262 in the Zero-profile group and 298 in the CCP group. Zero-profile implant had a lower rate of postoperative dysphagia at 2 weeks, 6 months, and 1 year (p = 0.0002, p = 0.008, and p = 0.001, respectively) than CCP implant. Zero-profile also reduced blood loss (p = 0.0001), while operation time and incidence of postoperative transient dysphagia had no statistical significance (p = 0.92, p = 0.42, respectively) between two groups. CONCLUSION: Based on the results of our analysis, the application of Zero-profile implant in ACDF had a lower rate of postoperative dysphagia at 2 weeks, 6 months, and 1 year than CCP implant. Zero-profile implant also had fewer blood loss during operation. More rigorous and adequately powered prospective randomized controlled trials with larger sample size are required to elucidate a more objective outcome.


Assuntos
Vértebras Cervicais/cirurgia , Discotomia/métodos , Próteses e Implantes , Fusão Vertebral/métodos , Espondilose/cirurgia , Vértebras Cervicais/patologia , Discotomia/efeitos adversos , Humanos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Próteses e Implantes/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Estudos Retrospectivos , Fusão Vertebral/efeitos adversos , Espondilose/diagnóstico , Espondilose/epidemiologia , Resultado do Tratamento
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