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1.
Environ Sci Technol ; 57(26): 9874-9883, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37335829

RESUMO

Advanced techniques for nickel (Ni(II)) removal from polluted waters have long been desired but challenged by the diversity of Ni(II) species (most in the form of complexes) which could not be readily discriminated by the traditional analytical protocols. Herein, a colorimetric sensor array is developed to address the above issue based on the shift of the UV-vis spectra of gold nanoparticles (Au NPs) after interaction with Ni(II) species. The sensor array is composed of three Au NP receptors modified by N-acetyl-l-cysteine (NAC), tributylhexadecylphosphonium bromide (THPB), and the mixture of 3-mercapto-1-propanesulfonic acid and adenosine monophosphate (MPS/AMP), to exhibit possible coordination, electrostatic attraction, and hydrophobic interaction toward different Ni(II) species. Twelve classical Ni(II) species were selected as targets to systematically demonstrate the applicability of the sensor array under various conditions. Multiple interactions with Ni(II) species were evidenced to trigger the diverse Au NP aggregation behaviors and subsequently produce a distinct colorimetric response toward each Ni(II) species. With the assistance of multivariate analysis, the Ni(II) species, either as the sole compound or as mixtures, can be unambiguously discriminated with high selectivity in simulated and real water samples. Moreover, the sensor array is very sensitive with the detection limit in the range of 4.2 to 10.5 µM for the target Ni(II) species. Principal component analysis signifies that coordination dominates the response of the sensor array toward different Ni(II) species. The accurate Ni(II) speciation provided by the sensor array is believed to assist the rational design of specific protocols for water decontamination and to shed new light on the development of convenient discrimination methods for other toxic metals of concern.


Assuntos
Ouro , Nanopartículas Metálicas , Ouro/química , Nanopartículas Metálicas/química , Níquel/química , Colorimetria , Água
2.
Anal Chem ; 93(3): 1811-1817, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33334097

RESUMO

Most metal probes based on gold nanoparticles (AuNPs) are designed for free metal ions in synthetic waters, and very few are applicable in the detection of metal-organic complexes ubiquitous in real water samples. In this study, we proposed a novel colorimetric nanoprobe strategy for complexed Cr(III) species based on the analyte-induced aggregation of AuNPs, as coated by a cationic surfactant tributylhexadecylphosphonium bromide (THPB) instead of traditional carboxyl modifiers. Such a detection system could be realized via both naked eye and/or UV-vis spectroscopy with detection limits of 8.0 and 0.29 µM, respectively, much lower than its allowable maximum level in industrial effluent as regulated by China EPA (1.5 mg Cr/L, ∼30 µM). The proposed detection system also exhibits high selectivity against various interfering substances including free ions, small organic molecules, and other metal-citrate complexes. The unique hydrolysis and extremely slow decomplexation of Cr(III) are believed to favor the formation of the specific interaction between Cr(III)-citrate and THPB-AuNPs, as verified by X-ray photoelectron spectroscopy characterization, thus endowing the nanoprobe with specific discrimination of the complexed Cr(III) via the aggregation of THPB-AuNPs. Also, the THPB-AuNPs could be stored at room temperature for 30 days and maintain constant detection performance. Moreover, the quantitative detection of Cr(III)-organic complexes with the background of various real water samples agreed well with that based on inductively coupled plasma atomic emission spectrometry, making it an attractive alternative for on-site detection of authentic samples containing Cr(III)-organic species.

3.
J Cardiothorac Surg ; 19(1): 303, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816890

RESUMO

BACKGROUND: Neurofibromatosis type 1 is a genetic disease that affects multiple organs and systems, leading to various clinical manifestations. In Neurofibromatosis type 1, rare intrathoracic meningoceles often occur alongside bone dysplasia. These meningoceles contain cerebrospinal fluid and can be mistakenly diagnosed as 'pleural effusion'. CASE PRESENTATION: In this case report, we mistakenly identified 'cerebrospinal fluid' as 'pleural effusion' and proceeded with drainage. This error posed significant risks to the patient and holds valuable implications for the future diagnosis and treatment of similar patients. CONCLUSIONS: In patients with Neurofibromatosis type 1 complicated by spinal deformity, there is a high incidence of intrathoracic meningoceles. Treatment strategies may differ based on the specific features of the lesions, and collaboration among multiple disciplines can significantly improve patient outcomes.


Assuntos
Erros de Diagnóstico , Meningocele , Neurofibromatose 1 , Derrame Pleural , Humanos , Neurofibromatose 1/diagnóstico , Neurofibromatose 1/complicações , Meningocele/diagnóstico , Derrame Pleural/diagnóstico , Tomografia Computadorizada por Raios X , Masculino , Feminino
4.
J Hazard Mater ; 476: 134981, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38908187

RESUMO

High-resolution identification of chromium (Cr) species, especially various organic-Cr complexes, in a convenient and economically-feasible manner is the prerequisite for achieving the advanced treatment of chromium wastewater. To this end, a colorimetric nano-Au sensor array was developed by taking advantage of the UV-spectra shift of gold nanoparticles (Au NPs) upon interaction with Cr species; specifically, four molecular modifiers [i.e., iminodiacetic acid (IDA), tripolyphosphate (TPP), cetyltrimethylammonium bromide (CTAB), and 1,5-diphenylcarbazide (DPC)] were intentionally employed for assembling nano-Au array receptors, which showed respective responses toward different Cr species through the formation of coordination, hydrophobic interaction, electrostatic attraction, and redox reaction, respectively; the "fingerprint" differences of the unique optical properties were then integrated for semi-quantitatively recognizing Cr species by pattern recognition techniques. Eleven ubiquitous Cr species [i.e., Cr(III), Cr(VI), and various Cr(III)-organic complexes] served as the model samples, which could be sensitively identified, no matter in individual or mixture mode, by the developed nano-Au sensor array on the basis of the colorimetric responses resulted from diverse nano-Au-aggregation behaviors, with excellent anti-interference ability in the simulated or actual water scenario. Attractively, the nano-Au sensor array can achieve very sensitive detection limit of the quantitative analyses of Cr species in a prompt in-situ manner, which usually requires a two-step process of separation and detection for the conventional analytical methods. Such a convenient strategy of Cr species discrimination conduces to rationally designing specific protocols for the advanced treatment of chromium wastewater.

5.
Waste Manag ; 175: 245-253, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38219462

RESUMO

Gentamicin mycelium residues (GMRs) abundant in organic substances were generated during the production of gentamicin. Inappropriate handling techniques not only waste valuable resources, they could also result in residual gentamicin into the natural environment, leading to the generation of antibiotic resistance genes (ARGs), which would cause a significant threat to ecological system and human health. In the present work, the effects of thermal treatment on the removal of residual gentamicin in GMRs, as well as the changes of associated ARGs abundance, antimicrobial activity and bioresources properties were investigated. The results indicated that the hazards of GMRs was significantly reduced through thermal treatment. The degradation rate of residual gentamicin in GMRs reached 100 %, the total abundance of gentamicin resistance genes declined from 8.20 to 1.14 × 10-5 and the antibacterial activity of the decomposition products of GMRs on Vibrio fischeri was markedly reduced at 200 °C for 120 min. Additionally, the thermal treatment remarkably influenced the bioresource properties of GMRs-decomposition products. The release of soluble organic matters including soluble carbohydrates and soluble proteins have been enhanced in GMRs, while excessively high temperatures could lead to a reduction of nutrient substances. Generally, thermal treatment technology was a promising strategy for synergistic reducing hazards and utilizing bioresources of GMRs.


Assuntos
Antibacterianos , Gentamicinas , Humanos , Gentamicinas/farmacologia , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Nutrientes , Micélio/metabolismo , Genes Bacterianos
6.
J Colloid Interface Sci ; 633: 866-875, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36495808

RESUMO

Phosphorus (P) control has been recognized as an imperative task to mitigate water eutrophication and settle the imminent shortage of P resources. Despite intensive effort put into this matter, it is still generally challenging for the current methods to remove and even potentially recover phosphorus (as phosphate) from complicated water matrices. To this end, we proposed a novel nanocomposite via coupling polystyrene anion exchanger (PsAX) with hydrated neodymium oxide (HNdO) nanoparticle for selective removal of phosphate. The developed nanocomposite, i.e., HNdO-PsAX, exhibited quite stable and efficient phosphate adsorption over a wide pH range of 3.0-10.0 with the maximum adsorption capacity as 85.4 mg P/g. It also showed satisfied anti-interference against various competing substances; notably, HNdO-PsAX obviously outperformed Phoslock, a commercial lanthanum-based adsorbent exclusively for phosphate sequestration, particularly under the interference of bicarbonate and humic acid, which were admitted as the paralyzing factors for Phoslock. The superior affinity of HNdO-PsAX towards phosphate, driven by the specific Nd-P inner-sphere complexation as evidenced by XPS, FT-IR, and the lattice evolution of HNdO nanoparticle, renders the nanocomposite eminently suitable for sequestrating trace phosphate. Fixed-bed treatment validated that HNdO-PsAX was capable of treating ∼11,800 bed volume of a simulated wastewater (from 2.0 to below 0.5 mg P/L), approximately 12 times higher than that of the previously reported Fe-based nanocomposite (HFO-PsAX, ∼ 900 BV); also, a satisfactory outcome in treating authentic municipal wastewater by HNdO-PsAX and the feasibility of regenerating the exhausted one by a binary NaOH-NaCl solution were recognized. This work provides a new potion of enhanced phosphorous control for surface water and wastewater.


Assuntos
Nanocompostos , Poluentes Químicos da Água , Água , Fosfatos/química , Águas Residuárias , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/química , Fósforo , Nanocompostos/química , Adsorção , Bicarbonatos , Concentração de Íons de Hidrogênio , Cinética
7.
Water Res ; 246: 120705, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37827040

RESUMO

Organic phosphonates have been widely used in various industries and are ubiquitous in wastewaters, and efficient removal of phosphonates is still a challenge for the conventional processes because of the severe interferences from the complex water constitutions. Herein, an Nd-based nanocomposite (HNdO@PsAX) was fabricated by immobilizing hydrated neodymium oxide (HNdO) nanoparticles inside a polystyrene anion exchanger (PsAX) to remove phosphonates from high-salinity aqueous media. Batch experiments demonstrated that HNdO@PsAX had an excellent adsorption capacity (∼90.5 mg P/g-Nd) towards a typical phosphonate (1-hydrox-yethylidene-1,1-diphosphonic acid, HEDP) from the background of 8 g/L NaCl, whereas negligible HEDP adsorption was achieved by PsAX. Attractively, various coexisting substances (humic acid, phosphate, citrate, EDTA, metal ligands, and anions) exerted negligible effects on the HEDP adsorption by HNdO@PsAX under high salinity. FT-IR and XPS analyses revealed that the inner-sphere complexation between HEDP and the immobilized HNdO nanoparticles is responsible for HEDP adsorption. Fixed-bed experiments further verified that HNdO@PsAX was capable of successively treating more than 4500 bed volumes (BV) of a synthetic high-salinity wastewater (1.0 mg P/L of HEDP), whereas only ∼2 BV of effective treatment capacity was received by PsAX. The exhausted HNdO@PsAX was amenable to a complete regeneration by a binary NaOHNaCl solution without significant loss in capacity. The capability in removing other organic phosphonates and treating a real electroplating wastewater by HNdO@PsAX was further validated. Generally, HNdO@PsAX exhibited a great potential in efficiently removing phosphonates from high-salinity wastewater.


Assuntos
Nanocompostos , Organofosfonatos , Poluentes Químicos da Água , Águas Residuárias , Adsorção , Neodímio , Salinidade , Ácido Etidrônico , Espectroscopia de Infravermelho com Transformada de Fourier , Ânions , Água , Poluentes Químicos da Água/análise
8.
Infect Drug Resist ; 16: 7613-7620, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38107430

RESUMO

Purpose: Early diagnosis of spinal infections remains challenging, and emerging metagenomic next-generation sequencing (mNGS) technology holds promise in addressing this issue. The aim of this study is to investigate the diagnostic efficacy of mNGS in spinal infections. Patients and Methods: A total of 78 cases with suspected spinal infections were enrolled in this study, all of whom underwent laboratory, histopathological and mNGS examinations upon admission. Lesion samples were obtained by surgical or C-arm-guided puncture. Sensitivity, specificity, positive predictive value and negative predictive value of culture and mNGS were calculated for statistical analysis. Results: With histopathological results as the reference, the included 78 patients were categorized into 50 cases in the spinal infection group and 28 cases in the aseptic group. The sensitivity (84%) and negative predictive value (77.14%) of mNGS were significantly higher than those of culture (32% and 44.26%, respectively), whereas no significant differences were observed in terms of specificity and positive predictive value. In the subgroup analysis for Mycobacterium tuberculosis, the sensitivity of mNGS (90.91%) and T-spot (90.91%) was significantly higher than that of culture (0). Additionally, mNGS demonstrated markedly higher specificity (100%) compared to T-spot (85.07%). Conclusion: This study underscores the substantial advantages of mNGS in terms of diagnostic accuracy and bacterial coverage for spinal infections. The findings provide compelling clinical evidence that supports the enhanced diagnostic efficacy of mNGS.

9.
Eco Environ Health ; 2(4): 264-277, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38435357

RESUMO

Amyloid nanofibrils (ANFs) are supramolecular polymers originally classified as pathological markers in various human degenerative diseases. However, in recent years, ANFs have garnered greater interest and are regarded as nature-based sustainable biomaterials in environmental science, material engineering, and nanotechnology. On a laboratory scale, ANFs can be produced from food proteins via protein unfolding, misfolding, and hydrolysis. Furthermore, ANFs have specific structural characteristics such as a high aspect ratio, good rigidity, chemical stability, and a controllable sequence. These properties make them a promising functional material in water decontamination research. As a result, the fabrication and application of ANFs and their composites in water purification have recently gained considerable attention. Despite the large amount of literature in this field, there is a lack of systematic review to assess the gap in using ANFs and their composites to remove contaminants from water. This review discusses significant advancements in design techniques as well as the physicochemical properties of ANFs-based composites. We also emphasize the current progress in using ANFs-based composites to remove inorganic, organic, and biological contaminants. The interaction mechanisms between ANFs-based composites and contaminants are also highlighted. Finally, we illustrate the challenges and opportunities associated with the future preparation and application of ANFs-based composites. We anticipate that this review will shed new light on the future design and use of ANFs-based composites.

10.
Nanoscale Adv ; 1(5): 1740-1745, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36134240

RESUMO

In this work, modified biomass ash (MA), obtained through the hydrothermal treatment technique with biomass ash (BA) and alkaline phosphate as raw materials, was used as a useful soil amendment to reduce the environmental risk of lead and was compared with raw ash. In order to confirm the composition changes from BA to MA, the materials before and after modification were characterized by using transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), Fourier transform infrared (FT-IR) spectroscopy, and X-ray diffraction (XRD). Subsequently, the suppression of the environmental risks of lead in the contaminated cropland soil by MA and BA was systematically investigated through pH evaluation, toxicity-extraction, and fractional analysis. The results show that needle-like hydroxyapatite nanoparticles were generated during the modification process of BA. After incubation with 5% BA and 5% MA for 60 days, the pH of soil samples increased from 5.46 to 7.20 and 6.83, respectively; the lead concentration by TCLP extraction decreased by about 52.6% and 95.2%, respectively. And the content of lead bound to RES increased from 36.28% to 49.09% and 59.58%, respectively. MA showed higher immobilization efficiency, better immobilization stability, and less disturbance to the soil pH than BA, and it can suppress the environmental risk of lead below the standard toxicity level. These results undoubtedly demonstrate that BA has great potential in the practical application of remediation of lead contaminated soil, and its modified product may become a useful amendment to suppress and/or eliminate the high environmental risk of lead by transforming industrial waste into useful nanomaterials for green environmental chemistry.

11.
PLoS One ; 13(8): e0202016, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30107005

RESUMO

Nitrous oxide (N2O) is a potent greenhouse gas (GHG) with agricultural soils representing its largest anthropogenic source. However, the mechanisms involved in the N2O emission and factors affecting N2O emission fluxes in response to various nitrogenous fertilizer applications remain uncertain. We conducted a four-year (2012-2015) field experiment to assess how fertilization scheme impacts N2O emissions from a rice-wheat cropping system in eastern China. The fertilizer treatments included Control (CK), Conventional fertilizer (CF), CF with shallow-irrigation (CF+SI), CF with deep-irrigation system (CF+DI), Optimized fertilizer (OF), OF with Urease inhibitor (OF+UI), OF with conservation tillage (OF+CT) and Slow-release fertilizer (SRF). N2O emissions were measured by a closed static chamber method. N2O emission fluxes ranged from 0.61 µg m-2 h-1 to 1707 µg m-2 h-1, indicating a significant impact of nitrogen fertilizer and cropping type on N2O emissions. The highest crop yields for wheat (3515-3667 kg ha-1) and rice (8633-8990 kg ha-1) were observed under the SRF and OF+UI treatments with significant reduction in N2O emissions by 16.94-21.20% and 5.55-7.93%, respectively. Our findings suggest that the SRF and OF+UI treatments can be effective in achieving maximum crop yield and lowering N2O emissions for the rice-wheat cropping system in eastern China.


Assuntos
Produtos Agrícolas , Meio Ambiente , Fertilizantes , Óxido Nitroso , Solo , China , Gases de Efeito Estufa , Óxido Nitroso/análise , Óxido Nitroso/metabolismo , Estações do Ano , Solo/química , Temperatura
12.
Org Lett ; 6(5): 763-6, 2004 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-14986969

RESUMO

Alpha-(N-carbamoyl)alkylcuprates (RCuCNLi or R2CuLi) react with allylic phosphates to afford homoallylic amines in good chemical yields. Regioselectivity is governed by steric factors in both the cuprate reagent and phosphate substrate and systems can be designed to give either the S(N)2' or S(N)2 substitution product cleanly. Excellent enantioselectivities can be achieved with either a scalemic alpha-di[(N-carbamoyl)alkyl]cuprate and an achiral phosphate or with a scalemic allylic phosphate and an achiral cuprate reagent. [reaction: see text]


Assuntos
Compostos Alílicos/química , Cobre/química , Compostos Organometálicos/química , Fosfatos/química , Aminas/síntese química , Lítio/química , Estrutura Molecular , Estereoisomerismo
13.
J Org Chem ; 71(15): 5674-8, 2006 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-16839148

RESUMO

The key transformation in the total synthesis of (+)-elaeokanine A was accomplished by asymmetric deprotonation of N-Boc pyrrolidine, followed by the reaction of the in situ generated enantioenriched stereogenic cuprate reagent with (E)-4-bromo-1-iodo-1-trimethylsilyl-1-butene with retention of configuration. N-Boc deprotection, followed by a one-pot olefin isomerization and intramolecular amine alkylation afforded a bicyclic vinyl bromide that was converted into (+)-elaeokanine A by sequential halogen metal exchange and reaction of the organolithium reagent with N-butanoylmorpholine.


Assuntos
Compostos Bicíclicos com Pontes/síntese química , Indolizinas/química , Alcenos/química , Alquilação , Aminas/química , Compostos Bicíclicos com Pontes/química , Cobre/química , Ciclização , Lítio/química , Estrutura Molecular , Morfolinas/química , Compostos Organometálicos/química , Estereoisomerismo , Compostos de Vinila/química
14.
J Org Chem ; 71(23): 8755-60, 2006 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-17081003

RESUMO

Enantioenriched propargyl mesylates or perfluorobenzoates react with alpha-(N-carbamoyl)alkylcuprates to afford scalemic alpha-(N-carbamoyl) allenes which undergo N-Boc deprotection and AgNO3-promoted cyclization to afford N-alkyl-3-pyrrolines. The synthetic sequence proceeds under optimal conditions with no loss of enantiopurity relative to the starting propargyl alcohols prepared by asymmetric addition of terminal alkynes to aldehydes.


Assuntos
Benzoatos/química , Cobre/química , Mesilatos/química , Compostos Organometálicos/química , Pirróis/síntese química , Estrutura Molecular , Pirróis/química , Estereoisomerismo
15.
J Org Chem ; 70(6): 2109-19, 2005 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-15760194

RESUMO

[reaction: see text] Carbamate deprotonation followed by treatment with CuCN.2LiCl affords alpha-(N-carbamoyl)alkylcuprates which react with propargyl halides, mesylates, tosylates, phosphates, acetates, and epoxides to give alpha-(N-carbamoyl) allenes via an anti-S(N)2' substitution process. Propargyl halides, sulfonates, and phosphates give good yields of carbamoyl allenes, while the acetates afford low yields. Propargyl substrates undergo regiospecific S(N)2' substitution in the absence of severe steric hindrance. The alpha-(N-carbamoyl) allenes can be cyclized to 2-oxazolidinones or deprotected to afford the free amines which can be cyclized to Delta(3)-pyrrolines with either AgNO(3) or Ru(3)(CO)(12).


Assuntos
Alcadienos/síntese química , Alcinos/química , Cobre/química , Compostos Organometálicos/química , Propanóis/química , Pirróis/síntese química , Estrutura Molecular , Compostos Organometálicos/síntese química
16.
J Org Chem ; 69(8): 2867-70, 2004 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-15074942

RESUMO

Both homo- and mixed lithium di-alpha-(heteroatom)alkylcuprates readily dimerize upon addition of halogens (e.g., I(2), Br(2)) or N-halosuccinimides to afford the coupled products in excellent yields. Higher yields result when the requisite alpha-(heteroatom)alkyllithium reagents are generated via deprotonation rather than by transmetalation of the corresponding stannanes. Mixed lithium dialkyl- or alkyl(aryl)cuprate reagents containing one alpha-(heteroatom)alkyl ligand and one simple alkyl or aryl ligand give significantly lower yields of coupled product. Low enantioselectivity has been achieved in the oxidative coupling of lithium (n-Bu)(2-pyrrolidinyl)cuprate.


Assuntos
Cobre/química , Compostos de Lítio/síntese química , Halogênios/química , Estrutura Molecular , Succinimidas/química
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