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1.
Int J Biol Macromol ; 254(Pt 2): 127840, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37926325

RESUMO

Cellulose/poly (glycerol citrate) reinforced with thiol-rich polyhedral oligomeric silsesquioxane and apple peel (POSS-SH@CAG-CEL/AP) was synthesized using gelation method in the presence of glutaraldehyde as a crosslinker agent and used as an efficient composite hydrogel for elimination of Tl(Ι) from aqueous solutions. This composite hydrogel and synthesized thiol-rich polyhedral oligomeric silsesquioxane were characterized by elemental analysis, FT-IR, NMR, TGA, and FE-SEM techniques. The effects of synthetic and environmental parameters on the adsorption capacity of the composite hydrogel were investigated and it was found that thiol-rich polyhedral oligomeric silsesquioxane has improved the hydrogel properties including the Tl(Ι) uptake and the thermal stability. The maximum adsorption capacity of 352.3 mg g-1 was obtained within 30 min under optimum reaction conditions. A typical Langmuir adsorption isotherm with was observed for adsorption of Tl(I) onto POSS-SH@CAG-CEL/AP and pseudo-second-order kinetic model provided the best correlation between experimental data. Thermodynamic studies showed that the Tl(I) adsorption was spontaneous process and exothermic. Also, the reusability tests confirmed that the POSS-SH@CAG-CEL/AP can be reused for four times without any remarkable change in its adsorption capacity. Thus, this reusable biobased composite hydrogel can be an ideal candidate for elimination of Tl(I) from aqueous solutions.


Assuntos
Hidrogéis , Poluentes Químicos da Água , Hidrogéis/química , Celulose , Tálio , Glicerol , Espectroscopia de Infravermelho com Transformada de Fourier , Ácido Cítrico , Concentração de Íons de Hidrogênio , Água , Cinética , Adsorção , Citratos , Compostos de Sulfidrila , Poluentes Químicos da Água/química
2.
Chemosphere ; 349: 140956, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38104732

RESUMO

The eco-friendly polymeric nanocomposite hydrogels were prepared by incorporating dendritic fibrous nanosilica (DFNS) and apple peel (AP) as reinforcements into the crosslinked polymer produced by cellulose (CL) and poly (glycerol tartrate) (TAGL) via gelation method and used for efficient adsorption of Pb2+, Co2+, Ni2+, and Cu2+ metal ions. DFNS and DFNS/TAGL-CL/AP samples were characterized by FESEM, FTIR, TEM, TGA, and nitrogen adsorption/desorption methods. The results of TGA analysis showed that the thermal stability of the prepared hydrogels improved significantly in the presence of DFNS. Both synthetic and environmental parameters were investigated and the adsorption capacity reached 560.2 (pH = 4) and 473.12 (pH = 5) mg/g for Pb2+ and Cu2+ respectively, using initial ion concentration of 200 mg/L. Also, the maximum adsorption capacity was 340.9, and 350.3 mg/g for Co2+ and Ni2+, respectively under optimum conditions (pH = 6, initial ion concentration of 100 mg/L). These experiments indicated that the DFNS/TAGL-CL/AP nanocomposite hydrogel has an excellent performance in removal of Pb2+ and can adsorb this toxic metal in only 30 min while the optimum contact time for other metals was 60 min. Pseudo-second-order and Langmuir models were used to define the kinetic and adsorption isotherms, respectively and thermodynamic studies demonstrated that the adsorption was endothermic for Co2+, Ni2+ and Cu2+, exothermic for Pb2+, and spontaneous in nature for all metal ions. Furthermore, the reusability tests indicated that the hydrogels could maintain up to 93% of their initial adsorption capacity for all metal ions after four cycles. Therefore, the prepared nanocomposite hydrogels can be suggested as efficient adsorbents to remove the toxic metals from wastewater.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Nanogéis , Glicerol , Celulose , Adsorção , Tartaratos , Chumbo , Metais Pesados/análise , Polímeros/química , Hidrogéis/química , Íons , Cinética , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio
3.
Sci Rep ; 13(1): 3511, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36864105

RESUMO

Poly(acrylic acid-co-acrylamide-co-maleic acid) (p(AA-co-AM-co-MA)) superabsorbent polymer was synthesized from acrylic acid (AA), acrylamide (AM), and maleic acid (MA) via free radical copolymerization. Results showed the presence of maleic acid in structure of superabsorbent has the key and superior role in creating a smart superabsorbent. The structure, morphology, and strength of the superabsorbent were characterized using FT-IR, TGA, SEM, and rheology analysis. The effect of different factors was investigated to determine the ability of water absorbency of the superabsorbent. According to optimized conditions, the water absorbency capacity of the superabsorbent in distilled water (DW) was 1348 g/g and in a solution containing 1.0 wt.% NaCl (SCS) was 106 g/g. The water retention ability of the superabsorbent was also investigated. The kinetic swelling of superabsorbent was identified by Fickian diffusion and Schott's pseudo-second-order model. Furthermore, the reusability of superabsorbent was studied in distilled water and saline solution. The ability of superabsorbent was investigated in simulated urea and glucose solutions, and very good results were obtained. The response ability of the superabsorbent was confirmed by swelling and shrinking behavior against changes of temperature, pH, and ionic strength.

4.
RSC Adv ; 12(30): 19579-19589, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35919373

RESUMO

A novel series of fused pyrazolo[5',1':2,3]imidazo[1,5-c]quinazolin-6(5H)-ones were synthesized and their affinity against the COVID-19 main protease was investigated using molecular docking study and compared to that of some used standard clinical drugs. These compounds were obtained in good to excellent yields from 63 to 91% in the presence of 30 mol% catalyst in ethanol at reflux for 2 h through an efficient one-pot three-component reaction including an intramolecular rearrangement and a cyclization through intramolecular nucleophilic reaction. The results of in silico studies showed that electronegativity, resonance effects, hydrophobic interaction, halogen and hydrogen bonding had significant effects on the performance of these compounds as an inhibitor ligand. Also, these results indicated the proper affinity of these compounds against the COVID-19 main protease with excellent binding energies (especially 4r = -8.77, 4q = -8.73 and 4m = -8.63) in comparison to remdesivir, chloroquine, hydroxychloroquine, molnupiravir and nirmatrelvir drugs.

5.
RSC Adv ; 12(19): 11740-11749, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35481103

RESUMO

Cellulose is an eco-friendly, efficient, and suitable substrate for use as a coating material and support in the preparation of catalysts. Herein, MNP-cellulose-OSO3H was prepared as an efficient heterogeneous catalyst composed of Fe3O4 nanoparticles covered with cellulose-OSO3H and used for the synthesis of trisubstituted imidazoles. The catalyst was characterized by FT-IR, CHNS, ICP, PXRD, EDAX, elemental mapping, SEM, TEM, zeta potential, TGA, and VSM techniques. The catalytic activity was evaluated in the one-pot three-component synthesis of trisubstituted imidazole derivatives using benzil or 9,10-phenanthrenequinone, different aldehydes, and ammonium acetate in EtOH solvent at 80 °C over 30 min. The yields of products were excellent, in the range 83-97%. The catalyst showed outstanding catalytic performance toward heating conditions and good reusability. Also, this methodology had several advantages, such as simple procedures, short reaction time, excellent yield, simple workup, and mild reaction conditions.

6.
Gels ; 8(2)2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35200502

RESUMO

Bone marrow-derived mesenchymal stem cells (MSCs) offer a promising therapeutic method for cardiac tissue regeneration. However, to monitor the fate of MSCs for tissue repair, a better stem cell delivery carrier is needed. Developing a unique injectable and shear-thinning dual cross-linked hybrid hydrogel for MSC delivery for cardiac tissue engineering is highly desirable. This hydrogel was synthesised using guest: host reaction based on alginate-cyclodextrin (Alg-CD) and adamantane-graphene oxide (Ad-GO). Here, the role of macromere concentration (10 and 12%) on the MSC function is discussed. Our hybrid hydrogels reveal a suitable oxygen pathway required for cell survival. However, this value is strongly dependent on the macromere concentrations, while the hydrogels with 12% macromere concentration (2DC12) significantly enhanced the oxygen permeability value (1.16-fold). Moreover, after two weeks of culture, rat MSCs (rMSCs) encapsulated in Alg-GO hydrogels expressed troponin T (TNT) and GATA4 markers. Noticeably, the 2DC12 hydrogels enhance rMSCs differentiation markers (1.30-times for TNT and 1.21-times for GATA4). Overall, our findings indicate that tuning the hydrogel compositions regulates the fate of encapsulated rMSCs within hydrogels. These outcomes may promote the advancement of new multifunctional platforms that consider the spatial and transient guidelines of undifferentiated cell destiny and capacity even after transplantation for heart tissue regeneration.

7.
ChemistryOpen ; 10(8): 764-774, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34351084

RESUMO

The conversion of soluble polyoxometalate into insoluble polyoxometalate is considered to be one of the major challenges in synthetic organic chemistry. Here, polyoxometalate was bonded to the salt part of an organic branch immobilized on the silica-coated Fe3 O4 nanoparticle and characterized using various techniques. The fabricated complex was used as a heterogeneous catalyst in a novel one-pot reaction for synthesis of benzo[4,5]imidazo[1,2-a]pyrimidin-2-ones using aromatic amines, dimethyl acetylenedicarboxylate (DMAD), derivatives of benzaldehyde and 2-aminobenzimidazole in water/ethanol as a green solvent. 21 derivatives of benzo[4,5]imidazo[1,2-a]pyrimidin-2-one were synthesized by this method and fully characterized. The high stability of the catalyst showed that it can be reused for 6 times without decreasing in activity. The combination of new synthetic method, new ferromagnetic heterogeneous nano-catalyst, green solvent and simple separation method were presented in this work.

8.
Int J Biol Macromol ; 182: 1893-1905, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34081953

RESUMO

In this work, a number of glucose unites in polymeric structure of cellulose was converted to 2,4-dihydroxy-3-(1-hydroxy-2-oxoethoxy)butanal (cellulose containing di aldehyde units (CCDAUs)) by oxidation with sodium periodate, followed by condensation with acetone to produce 5,7-dihydroxy-6-((1-hydroxy-4-oxopent-2-en-1-yl)oxy)hept-3-en-2-one unites (cellulose containing di ene units (CCDEUs)). This modified cellulose was characterized by different methods and applied as a copolymer and grafting agent to synthesize an eco-friendly (CCDEUs-g-poly(AA)/urea) superabsorbent with slow-release urea fertilizer. The created double bonds in C2 and C3 positions of ß-d-glucose units increased the linkage between cellulose and acrylic acid, leading to the formation of a strong network for slow-release urea fertilizer. Also, this modification created an expanded network for storage a high amount of water by increasing the cellulose flexibility. The reaction conditions for modification and synthesis of the superabsorbent, the oxidation degree value of glucose units, kinetics models, the effect of different saline solutions, various pH and reswelling time on the water absorbency, water retention capacity, reusability, biodegradability, and slow-release property were investigated. Also, the effect of synthesized CCDEUs-g-poly(AA)/urea on plant growth was tested and excellent results were obtained.


Assuntos
Celulose/química , Fertilizantes/análise , Ureia/análise , Acrilamidas/química , Acrilatos/química , Adsorção , Sulfato de Amônio/química , Difusão , Elementos Químicos , Fabaceae/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Cinética , Oxirredução , Reologia , Sais/química , Solo/química , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termogravimetria , Ureia/síntese química , Ureia/química , Água/química
9.
Mol Divers ; 25(2): 1123-1130, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32076910

RESUMO

Some 5-substituted 3-aminopyrazoles were used for the synthesis of isoindolo[2,1-c]pyrazolo[1,5-a]quinazoline and pyrazolo[5',1':2,3]pyrimido[6,1-a]isoindol derivatives via a mild and efficient one-pot three-component reaction with 2-formylbenzoic acid and different CH-acids under solvent-free condition.


Assuntos
Isoindóis/síntese química , Pirazóis/síntese química , Quinazolinas/síntese química , Catálise , Química Verde , Pirazóis/química
10.
Carbohydr Polym ; 250: 116959, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33049895

RESUMO

An efficient cellulosic superabsorbent based on a novel functional monomer 4-(6-aminohexyl) amino-4-oxo-2-butenoic acid (AHOB) and acrylic acid was successfully synthesized by free-radical solution polymerization and the effect of the AHOB monomer on the structure, morphology, thermal behavior and viscoelastic features of this superabsorbent was investigated by FTIR, SEM, TGA and rheology methods. Also, the influence of this monomer on the water absorption capacity in various pH and different saline solutions, kinetic behavior, water retention capacity and reusability of the superabsorbent was perused. The results of these experiments confirmed the significant role of the AHOB monomer in improving the properties of the superabsorbent. The excellent absorbency (800.37 g/g in distilled water and 78.02 g/g in 1 wt.% NaCl solution) and high water retention capacity of the prepared superabsorbent showed that it can be used as an efficient water-saving material for agricultural applications.

11.
Mol Divers ; 24(3): 753-761, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31321647

RESUMO

A novel one-pot four-component reaction of an aldehyde, malononitrile, hydrazine and 4,4-dimethyl-3-oxopentanenitrile is described. As regio- and chemoselective products, 7-amino-2-(tert-butyl)-5-aryl-4,5-dihydropyrazolo[1,5-a]pyrimidine-6-carbonitriles are formed during the course of the reaction.


Assuntos
Nitrilas/química , Nitrilas/síntese química , Pirazóis/química , Técnicas de Química Sintética , Cinética , Estereoisomerismo
12.
Mol Divers ; 23(4): 1011-1018, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30612260

RESUMO

A one-pot approach for the synthesis of a new series of 2-(alkylamino)-2-oxo-1-arylethyl-6,12-dioxo-6,12-dihydroindolo[1,2-b]isoquinoline-11-carboxylate derivatives via a four-component reaction using isatin, homophthalic anhydride, cyclohexyl isocyanide and an aldehyde is described. This method has several advantages such as being catalyst- and solvent-free reaction and a high-efficiency process with high to excellent yields.


Assuntos
Ácidos Carboxílicos/síntese química , Isoquinolinas/síntese química , Química Verde
13.
Iran J Nurs Midwifery Res ; 23(1): 40-44, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29344045

RESUMO

BACKGROUND: Forgiveness, as an intentional denial of your right of anger and aversion from a harmful deed, is related to many psychological processes of human which results in more psychological safety for people. The present study aimed to predict the psychological safety of nurses through different dimensions of forgiveness skill. MATERIALS AND METHODS: This correlational study was conducted on 170 nurses working in Kerman hospitals during 2016-2017 who were selected based on convenience random sampling. Edmondson psychological safety and Thompson Heartland forgiveness scale were used for data collection. Data were analyzed through Pearson correlation coefficient and multiple regression model. RESULTS: TThe results indicated that psychological safety has a significant relationship with self-forgiveness (p = 0.0001) and other-forgiveness (p = 0.04). Further, only self-forgiveness could significantly predict 0.07 of psychological safety variance (p = 0.003). CONCLUSIONS: Self-forgiveness skill can improve the nurses' psychological safety and reduce the harms caused by job pressures by reinforcing positive psychological factors. It is recommended to teach forgiveness skill through holding in-service classes to staff and study the relationship between psychological safety with other social life skills among nurses.

14.
Comb Chem High Throughput Screen ; 17(2): 132-40, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24164049

RESUMO

A one-pot, three-component reaction of an isatin and kojic acid with an active methylene compound such as ethyl cyanoacetate, methyl cyanoacetate and malononitrile in methanol using catalytic amount of DABCO to give 2'- amino-6'-(hydroxymethyl)-8'H-spiro[indoline-3,4'-pyrano[3,2-b]pyran]-2,8'-diones in good to excellent yields under reflux conditions, is described.


Assuntos
Técnicas de Química Combinatória , Indóis/síntese química , Piranos/síntese química , Compostos de Espiro/síntese química , Acetatos/química , Catálise , Indóis/química , Isatina/química , Nitrilas/química , Piperazinas/química , Piranos/química , Pironas/química , Compostos de Espiro/química
15.
Mol Divers ; 17(3): 619-25, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23703158

RESUMO

A one-pot, five-component condensation reaction of isocyanide, Meldrum's acid, arylidene malononitrile, and two amine molecules in CH2Cl2 at ambient temperature to give malonamide derivatives is described.


Assuntos
Malonatos/química , Malonatos/síntese química , Aminas , Dioxanos/química , Estrutura Molecular , Nitrilas/química , Estereoisomerismo
16.
J Pak Med Assoc ; 63(10): 1230-4, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24392550

RESUMO

OBJECTIVE: To evaluate the effect of note-taking skills training on the achievement motivation in learning. METHODS: The experimental study comprised graduate students of the 2010-11 batch at Kerman's Bahonar University and Kerman's Medical Sciences University, Iran. The study sample included 110 people; 55 in the test group, and 55 in the control group. They were randomly selected and replaced through the single-stage cluster sampling. To collect the data, a questionnaire was used. Pre-test was performed before the training session in two groups. After training course, a post-test was taken. For data analysis, the independent t-test, was used. RESULTS: The average pre-test score of the test group was 182 +/- 34.15, while for the control group it was 191 +/- 30.37 (p < 0.089). After the training, the post-test showed statistically significant change. The test group scored 220 +/- 20.94 against the controls who scored 195 +/- 27.26 (p < 0.001). CONCLUSION: The findings showed that achievement motivation in learning increased significantly after imparting training in note-taking skills. Authorities in the educational system should invest more for promotion of such skills.


Assuntos
Logro , Aprendizagem , Estudantes , Documentação , Humanos , Irã (Geográfico) , Competência Profissional , Estudantes de Medicina
17.
ACS Comb Sci ; 14(12): 657-64, 2012 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-23190397

RESUMO

A one-pot, three-component condensation reaction of an isatin, aminopyrazole, and alkyl cyanoacetate in water to give 2,6'-dioxo-1',5',6',7'-tetrahydrospiro[indoline-3,4'-pyrazolo[3,4-b]pyridine]-5'-carbonitrile with good yields, at 90 °C, using a Et(3)N as catalyst, is described.


Assuntos
Acetatos/química , Indóis/síntese química , Isatina/química , Pirazóis/química , Piridonas/síntese química , Compostos de Espiro/síntese química , Água/química , Indóis/química , Estrutura Molecular , Piridonas/química , Compostos de Espiro/química
18.
Addict Health ; 3(3-4): 111-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-24494125

RESUMO

BACKGROUND: Various studies have been conducted to determine the causes of drug abuse from a psychological perspective. Mental health has also been among the studied factors. The present study aimed to investigate the relationship between mental health and general self-efficacy beliefs, coping strategies and locus of control in male drug abusers. METHODS: This was a correlational descriptive study involving all male drug abusers (4,493 cases) at self-introducing detoxification centers in Kerman, Iran, during 2010-11. A total number of 354 patients were selected randomly with cluster sampling. Measurement tools were included Goldberg's General Health Questionnaire (GHQ-28), Generalized Self-Efficacy Scale (GSE-10), Coping Responses Inventory (CSI), and Internal-External Locus of Control Scale (I-E). The survey data were analyzed by SPSS using Pearson correlation and stepwise regression. FINDINGS: There were significant correlations between mental health and self-efficacy beliefs (r = -0.626), problem-oriented coping strategy (r = -0.535), emotion-oriented coping strategy (r = 0.573), external locus of control (r = -0.298), and internal locus of control (r = -0.525) (P < 0.01 for all). The results of the regression analysis showed that 58.7 percent of total variance of mental health can be estimated by general self-efficacy beliefs, coping strategies and locus of control. CONCLUSION: In general, the results showed that increased levels of general self-efficacy, problem-oriented coping strategy and internal locus of control will improve mental health. In contrast, decreased general self-efficacy, emotion-oriented coping strategy and external locus of control would lead to decreased mental health.

19.
Amino Acids ; 39(3): 911-6, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20221649

RESUMO

Histidine and arginine were applied to the synthesis of trisubstituted alkenes through a condensation of an aldehyde with an activated CH-acid such as ethyl cyanoacetate, malononitrile, acetyl acetone or ethyl acetoacetate during 5-12 h in water at room temperature.


Assuntos
Arginina/química , Histidina/química , Aldeídos/química , Alcenos/síntese química , Alcenos/química , Fenômenos Químicos , Modelos Químicos , Água/química
20.
Comb Chem High Throughput Screen ; 9(10): 771-6, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17168682

RESUMO

Tetraheterocyclic benzimidazo[1,2-a]quinazolin-4(1H)-one and tetrahydro-1,2,4-triazolo[5,1-b]quinazolin-8(4H)-one were synthesized in relatively high yields by the condensation reaction of an aldehyde and a cyclic beta-diketone with 2-aminobenzothiazole, 2-aminobenzimidazole or 3-amino-1,2,4-triazole without using any catalyst under solvent-free conditions.


Assuntos
Aldeídos/química , Amitrol (Herbicida)/química , Benzimidazóis/química , Benzimidazóis/síntese química , Técnicas de Química Combinatória/métodos , Quinazolinas/química , Quinazolinas/síntese química , Triazóis/síntese química , Estrutura Molecular , Solventes/química , Triazóis/química
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