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1.
Water Sci Technol ; 80(4): 654-658, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31661444

RESUMO

The reusability of spent adsorbents is the most important characteristic for their practical application. The process of MgFe2O4 regeneration after methylene blue (MB) adsorption was studied. The effect of the nature (HCl, HNO3, and MgCl2) and the concentration (10-3-10-1 M) of regeneration agents was established. All the regeneration agents at 10-3 and 10-2 M had high efficiency and adsorption capacity recovery reached 80-90%, whereas for 10-1 M concentration the adsorption efficiency was in the range of 4.5-36.2%. It was shown that the concentration of desorbed MB was much less than what had been previously adsorbed and did not correlate with regeneration efficiency. The unusual behavior of MgFe2O4 during regeneration could be due to different mechanisms of regeneration by OH3+ and Mg2+ ions: (i) for acidic regeneration the main process was the non-specific adsorption of OH3+ ions in a diffusion layer and the substitution of adsorbed MB due to electrostatic forces; (ii) in the case of Mg2+ as a regeneration agent, there was specific adsorption due to the completion of a crystal lattice of MgFe2O4 nanoparticles by Mg2+ ions (according to the rules of Fayans-Pannet) with the formation of new Mg-OH adsorption sites and the super-equivalent adsorption of Mg2+ ions (according to DLVO (Derjaguin, Landau, Verwey, and Overbeek) theory) accompanied by a recharge of the MgFe2O4 surface. These phenomena of MgFe2O4 regeneration using Mg2+ ions must be taken into account in the theory and practice of adsorption.


Assuntos
Poluentes Químicos da Água , Adsorção , Difusão , Íons , Azul de Metileno
2.
Water Sci Technol ; 80(3): 448-457, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31596256

RESUMO

In the present study, continuous-flow column experiments (using glass column, Tygon tubing, and peristaltic pump Manostat Carter) were conducted to investigate the performance of permeable sorption barriers for the removal of cadmium and zinc from synthetic groundwater. Zeolite, ion-exchange resin and granular activated carbon as reactive materials were used. The effectiveness and stability of reactive materials were studied by monitoring of changes of metal ions concentration and selected background anions and cations concentration in groundwater during its flow through columns. Results showed that ion exchange resin was the most effective material of permeable reactive barrier (PRB). Performance of resin barrier remained effective (>99.5% metal ions removal) for the time corresponding to on average of about 10,000 min. The high efficiency of ion-exchange resin in PRB for removal of heavy metals from groundwater was coupled with its reactivity and long barrier lifetime. The breakthroughs in the column tests on activated carbon and zeolite using synthetic groundwater occurred much earlier as compared to resin. Therefore, the system using resin requires smaller amount to treat a given volume of groundwater as compared to other materials. Moreover, the presence of other ions did not impact on activity and permeability of barrier filled with resin.


Assuntos
Cádmio/análise , Água Subterrânea/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Zinco/análise , Íons
3.
J Environ Manage ; 252: 109617, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31605906

RESUMO

Pharmaceuticals are a wide class of emerging pollutants due to their continuous and the increasing consumption of users. These pollutants are usually found in the real environment as mixtures alone or with metal ions. Thus, the migration risk increases, which complicates the removal of pharmaceuticals because of the combined and synergistic effects. The focus of treatment of pharmaceutical mixtures and their coexistence with metals is of considerable importance. For this purpose, adsorption has been efficiently applied to several studies for the treatment of such complex systems. In this article, the coadsorption behavior of pharmaceuticals in the absence and existence of metals on several adsorbents has been reviewed. The adsorption isotherms and kinetics of these two systems have been analyzed using different models and discussed. Important challenges and promising routes are suggested for the future development of the coadsorption of the studied systems. This article provides an overview on the most utilized and effective adsorbents, widely studied adsorbates, best applied isotherm and kinetic models, and competitive effect in coadsorption of pharmaceuticals, both with and without metals.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Adsorção , Íons , Cinética , Metais
4.
Bratisl Lek Listy ; 120(7): 516-522, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31602987

RESUMO

OBJECTIVES: The aim of this study was to evaluate the toxic effect of AlNPs on rat brain mitochondria and compare it with that of aluminium's ionic form. METHODS: Mitochondria were isolated from rat brain. Isolated mitochondria were treated with normal saline (Control) and different concentrations of aluminium ions (AlIs) and AlNPs (50, 100 and 200 µM). Then, the effect of AlNPs on electron transport chain complexes as well as various endpoints such as mitochondrial oxidative damage (reactive oxygen species, lipid peroxidation, glutathione, and protein carbonyl) and mitochondrial function were assessed. Also, apoptosis was evaluated by cytochrome c release, mitochondrial membrane potential and swelling. RESULTS: When compared to the control group, the exposure to AlNPs showed a marked elevation in oxidative stress markers and inhibition of complex III which was accompanied by disturbance in mitochondrial function. Also, AlNPs induced a significant collapse of mitochondrial membrane potential, mitochondrial swelling, and cytochrome c release. CONCLUSIONS: The comparison of mitochondrial toxicity markers between both forms of aluminium revealed that the toxic effect of AlNPs on isolated brain mitochondria was substantially greater than that that caused by AlIs, which can probably be ascribed to its higher reactivity (Tab. 1, Fig. 8, Ref. 45).


Assuntos
Alumínio/toxicidade , Encéfalo/diagnóstico por imagem , Mitocôndrias/efeitos dos fármacos , Nanopartículas/toxicidade , Animais , Apoptose , Citocromos c/metabolismo , Glutationa/metabolismo , Íons , Peroxidação de Lipídeos , Potencial da Membrana Mitocondrial , Estresse Oxidativo , Carbonilação Proteica , Ratos , Espécies Reativas de Oxigênio/metabolismo
5.
Chem Commun (Camb) ; 55(83): 12507-12510, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31576386

RESUMO

Charge reduction and neutralization of electro-sprayed peptides are realized by selective gas-phase photocleavage of tailored covalent tags. The concept is demonstrated with four model peptides in positive and negative ion modes and tagged insulin as the largest construct.


Assuntos
Insulina/química , Peptídeos/química , Vácuo , Íons/química , Estrutura Molecular , Processos Fotoquímicos
6.
Chem Commun (Camb) ; 55(83): 12463-12466, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31576854

RESUMO

Herein, an ultrasensitive electrochemical biosensor is proposed for the quantification of the Flu A virus biomarker DNA (fDNA), and is based on loop-mediated isothermal amplification-generated hydrogen ions (LAMP-H+) which induce the formation of the dimer i-motif structure (DiMS) for signal transduction, coupled with exonuclease III (ExoIII)-assisted DNA walking for signal dual-amplification.


Assuntos
Técnicas Biossensoriais , DNA Viral/análise , Técnicas Eletroquímicas , Vírus da Influenza A/química , Técnicas de Amplificação de Ácido Nucleico , Prótons , Biomarcadores/análise , Dimerização , Íons/química
7.
Chem Commun (Camb) ; 55(75): 11299-11302, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31475999

RESUMO

Fabrication of ordered assemblies with protein nanocages as building blocks has attracted great attention. Here, we re-engineered the exterior surface of the smallest natural nanocage, DNA-binding protein from starved cells (Dps), to yield a highly ordered architecture triggered by zinc ions. The resulting architecture possesses a bcc superstructure, the assembly and disassembly of which are reversible and can be regulated by the salt concentration.


Assuntos
Proteínas de Ligação a DNA/química , Nanoestruturas/química , Engenharia de Proteínas , Zinco/química , Proteínas de Ligação a DNA/síntese química , Íons/química , Tamanho da Partícula , Sais/química , Propriedades de Superfície
8.
Int J Nanomedicine ; 14: 6339-6356, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31496690

RESUMO

Objective: The rational combination of immunotherapy with standard chemotherapy shows synergistic clinical activities in cancer treatment. In the present study, an oral powder formulation of pemetrexed (PMX) was developed to enhance intestinal membrane permeability and investigate its application in metronomic chemotherapy in combination with immunotherapy. Methods: PMX was ionically complexed with a bile acid derivative (Nα-deoxycholyl-l-lysyl-methylester; DCK) as a permeation enhancer and mixed with dispersing agents, such as poloxamer 188 (P188) and Labrasol, to form an amorphous oral powder formulation of PMX/DCK (PMX/DCK-OP). Results: The apparent permeability (Papp) of PMX/DCK-OP across a Caco-2 cell monolayer was 2.46- and 8.26-fold greater than that of PMX/DCK and free PMX, respectively, which may have been due to the specific interaction of DCK with bile acid transporters, as well as the alteration of membrane fluidity due to Labrasol and P188. Furthermore, inhibition of bile acid transporters by actinomycin D in Caco-2 cell monolayers decreased the Papp of PMX/DCK-OP by 75.4%, suggesting a predominant role of bile acid transporters in the intestinal absorption of PMX/DCK-OP. In addition, caveola/lipid raft-dependent endocytosis, macropinocytosis, passive diffusion, and paracellular transport mechanisms significantly influenced the permeation of PMX/DCK-OP through the intestinal membrane. Therefore, the oral bioavailability of PMX/DCK-OP in rats was 19.8%±6.93%, which was 294% higher than that of oral PMX. Moreover, an in vivo anticancer efficacy study in B16F10 cell-bearing mice treated with a combination of oral PMX/DCK-OP and intraperitoneal anti-PD1 exhibited significant suppression of tumor growth, and the tumor volume was maximally inhibited by 2.03- and 3.16-fold compared to the oral PMX/DCK-OP and control groups, respectively. Conclusion: These findings indicated the therapeutic potential of a combination of low-dose oral chemotherapy and immunotherapy for synergistic anticancer efficacy.


Assuntos
Ácido Desoxicólico/química , Composição de Medicamentos , Intestinos/efeitos dos fármacos , Pemetrexede/farmacologia , Administração Oral , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/sangue , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Disponibilidade Biológica , Transporte Biológico/efeitos dos fármacos , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Ácido Quenodesoxicólico/análogos & derivados , Ácido Quenodesoxicólico/química , Humanos , Íons , Lisina/análogos & derivados , Lisina/química , Camundongos Endogâmicos BALB C , Pemetrexede/administração & dosagem , Pemetrexede/sangue , Pemetrexede/farmacocinética , Permeabilidade , Ratos Sprague-Dawley
9.
Phys Chem Chem Phys ; 21(36): 19795-19804, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31482888

RESUMO

Allostery plays important roles in the regulation of many biological processes, such as signal transduction and transcriptional regulation. Although great advances have been achieved in understanding the allosteric mechanism through experimental and theoretical investigations, the details of the allosteric process are still not clear. Here, using the N-terminal domain of calmodulin (nCaM) as the model protein, we reported the atomic level characterization of the allosteric process induced by Ca2+ binding through extensive and unbiased molecular dynamics simulations. In two trajectories, it was found that Ca2+ first binds to EF-hand 2 and then induces the conformational transformation of nCaM from the Apo to Holo state assisted by second Ca2+ binding to EF-hand 1 completely. The binding order was consistent with a recent experimental result. The simulations also indicated that the two EF-hands changed conformations synergistically and the EF-hand 2 showed an earlier and more gradual conformational transition. Meanwhile, the allosteric process of nCaM triggered by Ca2+ binding might be completed within hundreds of nanoseconds in a two-state-like manner. This was validated by biased simulations, in which the Ca2+ ions were restrained near the binding sites. This work provides the molecular details of the conformational transition of nCaM triggered by Ca2+ binding.


Assuntos
Cálcio/química , Calmodulina/química , Íons/química , Simulação de Acoplamento Molecular , Domínios Proteicos , Ligação Proteica , Conformação Proteica
10.
Environ Monit Assess ; 191(9): 564, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31414237

RESUMO

The objective of this study was to determine eco-edaphic characteristics and influence of different substrates on mineral characteristics of facultative serpentinophyte. The total concentration of 20 elements Al, As, B, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, P, Pb, S, Se, and Zn in soil samples and aboveground parts of medicinal plant species Teucrium montanum from various calcareous and serpentinite habitats in the territory of Serbia was determined. The concentration of the elements was established by inductively coupled plasma optical emission spectrometry-ICP-OES. The obtained results showed that the quantities of certain elements Al, As, B, Ca, Cd, Cu, K, Li, P, Se, and Zn were detected more in the soil samples from calcareous habitats in comparison to the quantities of other metals Co, Cr, Fe, Mg, Mn, Na, Ni, which were more frequently found in the soil samples from the serpentinite habitats. Analyzed plant samples from calcareous habitats contained higher concentrations of Al, Ca, Li, and Zn as opposed to serpentinite containing higher concentrations of Co, Cr, Fe, Mg, Mn, Na, Ni, and Se. Examined species can accumulate macro- and microelements in different quantities, depending on the substrate type. Differences in the concentration of certain elements in the soil samples and aboveground parts of the T. montanum from calcareous and serpentinite habitats indicate significant phenotypic plasticity of the investigated species as well as the existence of specific serpentinite ecotypes developed by the activity of various edaphic factors.


Assuntos
Asbestos Serpentinas/análise , Carbonato de Cálcio/análise , Solo/química , Teucrium/metabolismo , Ecossistema , Monitoramento Ambiental/métodos , Íons , Metais/análise , Minerais/análise , Sérvia
12.
Water Sci Technol ; 80(1): 98-108, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31461426

RESUMO

The sorption of Cu ions on pure fly ash-based geopolymer, fly ash-based geopolymer with Pb ions addition (modified) and zeolite NaX was studied. Taguchi's approach was applied to determine the impact of solute concentration (c), temperature (T), mixing time (t) and sorbent type (S) on the sorption of Cu ions onto different sorbents under batch conditions. Optimum experimental conditions and influence of controllable factors were determined using the larger-the-better approach. The influence in descending order is c > S > t > T, for both removal and loading. Also, the impact of sorbent type and solute concentration on the process equilibrium was examined. The equilibrium amount of Cu retained on the sorbents in equilibrium (qe) was as follows: pure geopolymer - 1.169 mmol g-1, modified geopolymer - 1.186 mmol g-1, and zeolite NaX - 1.695 mmol g-1. The experimental data were modelled using Jovanovic, Khan, Baudu, and Fritz-Schlünder isotherm models and their goodness of fit were compared. The Baudu isotherm model was the most useful in predicting the equilibrium of Cu sorption on pure and modified geopolymer. Goodness of fit of the selected isotherm models for the sorption of Cu ions on zeolite NaX was in the order: Fritz-Schlünder > Khan > Jovanovic > Baudu.


Assuntos
Cobre/química , Zeolitas , Adsorção , Concentração de Íons de Hidrogênio , Íons , Cinética , Modelos Químicos
13.
Water Sci Technol ; 79(12): 2221-2230, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31411576

RESUMO

This research analyzes the use of natural shrimp shell and commercial chitin for biosorption of metal ions in surface runoff. Investigation of the use of these biosorbent materials in drainage systems becomes a management measure for two extremely important issues in Brazil, fish waste management and the surface runoff quality. Methodological procedures involved treatments with different amounts of unprocessed shrimp shell and commercial chitin (5g and 10g) for 200mL of a compensatory drainage mechanism (infiltration swale). The contact time of biosorbent and runoff was 24h and removal of metal ions Fe, Mn, Zn, Cu, Ni, Pb, and Cr was studied. Tests with unprocessed shrimp shell showed high concentrations of metallic ions (Pb, Ni, and Cu) causing contamination of the environment. However, the two biosorbents presented good removal of specific metallic ions (Fe, Mn, Zn, and Cr). These results indicate the need for a biosorbent pre-treatment prior to full-scale use. We indicate the need for a more detailed investigation of water quality in the environment used for shrimp farming. Tests with commercial chitin presented satisfactory results for two concentrations tested. Tests with 10g of commercial chitin allowed removal of all tested metal ions (Fe, Mn, Zn, Cu, Ni, Pb, Cr) with removal percentage between 6.7% and 84.4%. This efficiency may be related to the chitin's composition (shrimp, crustaceans, and crab) and to the chemical process applied to the product prior to commercialization.


Assuntos
Metais Pesados , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água , Adsorção , Animais , Brasil , Íons
14.
Water Sci Technol ; 79(12): 2289-2297, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31411583

RESUMO

In this paper, the removal performance and mechanism of xanthated chitosan (XCTS) towards heavy metal ions are investigated. XCTS possesses both strong chelating abilities and excellent flocculation properties, which can effectively remove several kinds of heavy metal ions, such as Cr3+, Cu2+, Mn2+, Ni2+, Pb2+ and Zn2+. It has a good potential for practical application. In a flocculation test of a mixed component solution, the removal rates of Cr3+, Cu2+ and Cd2+ reach 100%, 100% and 99.1%, respectively. The removal rates are significantly greater than that of a single component solution. It indicates that there is a synergistic effect between different metal ions. Moreover, the selectivity of XCTS for Cr3+ and Cu2+ is obviously superior to that for Cd2+; XCTS is easier to combine with the heavy metal ions belonging to hard acids.


Assuntos
Quitosana , Metais Pesados , Quelantes , Floculação , Íons , Eliminação de Resíduos Líquidos
15.
Waste Manag ; 98: 135-143, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31446253

RESUMO

The predominant heavy metals in MSWI fly ash and electrolytic manganese residue (EMR) were determined to be Zn, Pb, Cd, and Mn, with lesser amounts of Cu and Cr. The curing efficiency of heavy metals in MSWI fly ash and EMR was improved using complex alkaline activators (NaOH and KOH), base addition (calcium hydroxide and complex Portland cement), and EMR calcining (at 800 °C for 3 h) based on a geopolymeric system. The best formulation of the geopolymeric system was composed of 75 wt% MSWI fly ash and 25 wt% EMR with a KOH/NaOH (1:1) complex solution (7.5 M OH-)/solid of 0.5. Calcium ions were dissolved aluminosilicate under the strongly basic conditions to form complex products (ternesite) which further improved the strength. The primary curing mechanism of heavy metals (Pb, Zn, Cd, Mn, Cr, and Cu) mainly was primarily influenced by the acid-base buffering capacity of geopolymers, followed by the physical encapsulation of geopolymeric gels.


Assuntos
Metais Pesados , Eliminação de Resíduos , Carbono , Cinza de Carvão , Incineração , Íons , Manganês , Material Particulado
16.
Aquat Toxicol ; 214: 105263, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31376794

RESUMO

The potential toxicity of silver nanoparticles (AgNPs) to the early stages of fish is still unclear. This study used zebrafish embryos as a model to investigate the toxic effects of AgNPs on ion regulation by skin ionocytes. Zebrafish embryos were exposed to AgNPs for 96 h (4-100 h post-fertilization (hpf)) or 4 h (96-100 hpf). After 96 h of exposure to 5 and 10 mg/L AgNPs, survival rates had decreased to 42% and 0%, respectively; the body length had also significantly decreased at 5 mg/L. Whole-body Na+ and K+ contents significantly decreased at 1 and 3 mg/L, while Ca2+ contents decreased at ≥0.1 mg/L. H+ secretion by the skin significantly decreased at 1 mg/L. The density of skin ionocytes labeled with rhodamine 123 (a mitochondrion marker) decreased by 25% and 55% at 1 and 3 mg/L, respectively; and 54% of ionocytes (at 3 mg/L) were deformed from an oval to a spinous shape. After 4 h of exposure to 1 and 5 mg/L, whole-body Na+ and Ca2+ contents, H+ secretion, and density of ionocytes had also significantly decreased. This study revealed the toxicity of AgNPs to skin ionocytes and ion regulation in the early stages of zebrafish embryos.


Assuntos
Embrião não Mamífero/metabolismo , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Peixe-Zebra/embriologia , Ácidos/metabolismo , Animais , Contagem de Células , Forma Celular/efeitos dos fármacos , Embrião não Mamífero/citologia , Embrião não Mamífero/efeitos dos fármacos , Íons , Larva/efeitos dos fármacos , Análise de Sobrevida , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/anatomia & histologia
17.
Int J Nanomedicine ; 14: 5697-5711, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413570

RESUMO

Purpose: Calcium (Ca) and magnesium (Mg) ions have been used as promising bioactive ions in the surface chemistry modification of titanium (Ti) bone implants to increase bone regeneration capacity. However, it is not clear which (Ca or Mg) plays the more important role in the early osteogenic differentiation of mesenchymal stem cells (MSCs) when applied to the surface of commercially available microstructured Ti implants. This study investigated the relative effect of these two ions on the early osteogenic functionality of primary mouse bone marrow MSCs in order to obtain insights into the surface design of Ti implants with enhanced early osteogenic capacity. Methods and results: Wet chemical treatment was performed to modify a microrough Ti implant surface using Ca or Mg ions. Both the Ca and Mg-incorporated surfaces accelerated early cellular events and the subsequent osteogenic differentiation of MSCs compared with an unmodified microrough Ti surface. Surface Mg modification exhibited a more potent osteoblast differentiation-promoting effect than the Ca modification. Surface Mg incorporation markedly inhibited the phosphorylation of ß-catenin. Conclusion: These results indicate that alteration of the surface chemistry of microstructured Ti implants by wet chemical treatment with Mg ions exerts a more effect on promoting the early osteogenic differentiation of MSCs than Ca ions by enhancing early cellular functions, including focal adhesion development and stabilization of intracellular ß-catenin.


Assuntos
Cálcio/farmacologia , Magnésio/farmacologia , Células-Tronco Mesenquimais/citologia , Osteogênese/efeitos dos fármacos , Próteses e Implantes , Titânio/farmacologia , Animais , Cátions Bivalentes/farmacologia , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Adesões Focais/efeitos dos fármacos , Íons , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/ultraestrutura , Camundongos , Fosforilação/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Propriedades de Superfície , Água/química , Difração de Raios X , beta Catenina/metabolismo
18.
Bioresour Technol ; 292: 121948, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31408776

RESUMO

To improve the adsorption efficiency, a H3PO4-modified biochar (CFCP) was prepared using chicken feather and applied to Cd2+ and Pb2+ adsorption. The pseudo-second-order model could explain the Cd2+ and Pb2+ adsorption behavior. CFCP had faster adsorption rate than non-modified biochar (CFC2). The Langmuir and Freundlich isotherm could better describe the Cd2+ and Pb2+ adsorption, respectively. The value of qm for Cd2+ adsorption and KF for Pb2+ adsorption by CFCP was 7.84 mg·g-1 and 24.41 mg1-(1/n)·L1/n·g-1, which was 1.38 and 5.41 times of the corresponding results of CFC2. Relative to Cd2+, Pb2+ was selectively adsorbed by biochars in the binary metal system. Phosphate precipitation explained in part the selective adsorption of Pb2+. Proline, glucose, and pH (4-6) had little influence on Cd2+ and Pb2+ adsorption. Electrostatic interaction, precipitation, and O-H bonds were the primary adsorption mechanisms. The increased N-containing heterocycles of CFCP accounted for the increased Cd2+ and Pb2+ adsorption.


Assuntos
Cádmio , Galinhas , Adsorção , Animais , Carvão Vegetal , Plumas , Íons , Chumbo , Ácidos Fosfóricos
19.
Inorg Chem ; 58(17): 11294-11299, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31411862

RESUMO

The first two examples of polyoxopalladates(II) (POPs) containing tetravalent metal ion guests, [MO8Pd12(PO4)8]12- (M = SnIV, PbIV), have been prepared and structurally characterized in the solid state, solution, and gas phase. The interactions of the metal ion guests and the palladium-oxo shell were studied by theoretical calculations. The POPs were shown to possess anticancer activity by causing oxidative stress inducing caspase activation and consecutive apoptosis of leukemic cells.


Assuntos
Antineoplásicos/farmacologia , Metais Pesados/química , Compostos Organometálicos/farmacologia , Polímeros/química , Antineoplásicos/síntese química , Antineoplásicos/química , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Humanos , Íons/química , Modelos Moleculares , Compostos Organometálicos/síntese química , Compostos Organometálicos/química
20.
Ying Yong Sheng Tai Xue Bao ; 30(7): 2211-2217, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31418223

RESUMO

Previous studies on negative air ion (NAI), an important index for evaluating atmospheric quality, has been focused on field observation, and less on NAI under controlled condition. In this study, the NAI concentrations of different individual abundance of Liquidambar formosana and Taxus wallichiana were continuously monitored under the same climatic conditions in Hushan Experimental Base of Qianjiangyuan Forest Ecosystem Research Station, Zhejiang Province from September to October 2018. Changes of NAI concentration were monitored under different levels of air temperature and relative humidity to explore the effects of forest vegetation and meteorological factors on NAI. The results showed that both species significantly increased the NAI concentration. Plant abundance was positively correlated with the NAI concentration, and the relationship between them fitted the quadratic function with the plant abundance ranging from 0 to 50. The fitting equations for L. formosana and T. wallichiana were as follows: y=-0.0484x2+4.7005x+345.7 (R2=0.62), y=-0.0207x2+1.9189x+365.91 (R2=0.34). There was a significant positive correlation between NAI concentration and air temperature in the range of 5-30 ℃ with a fitting equation of y=0.4139x2-9.2229x+89.919 (R2=0.92). The NAI concentration and the relative humidity of air in the range of 56%-87% were positively correlated with a fitting equation of y=3.6508e0.0526x(R2=0.94).


Assuntos
Ecossistema , Conceitos Meteorológicos , Temperatura Ambiente , Umidade , Íons
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