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1.
Chemosphere ; 291(Pt 2): 132690, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34715105

RESUMO

Resource constraints and deteriorating environment have made it necessary to look for intensification of the industrial processes, to recover value from spent streams for reuse. The development of reverse osmosis has already established that water can be recovered from aqueous streams in a cost-effective and beneficial manner to the industries. With the development of several membrane processes and membrane materials, the possibility of recovering value from the effluents looks like a workable proposition. In this context, the potentialities of the different membrane processes in value recovery are presented. Among the pressure-driven processes, reverse osmosis can be used for the recovery of water as value. Nanofiltration has been used for the recovery of several dyes including crystal violet, congo red, methyl blue, etc., while ultrafiltration has been used in the fractionation of different solute species using membranes of different pore-size characteristics. Diffusion dialysis is found useful in the separation of acids from its salt solutions. Bipolar membrane electrodialysis has the potential to regenerate acid and base from salt solutions. Thermally driven membrane distillation can provide desalinated water, besides reducing the temperature of hot discharge streams. Passive membrane processes such as supported liquid membranes and membrane-assisted solvent extraction have been found useful in separating minor components from the wastewater streams. The details are discussed to drive home that membrane processes can be useful to achieve the objectives of value recovery, in a cost-effective manner through process intensification, as they are more compact and individual streams can be treated and value used seamlessly.


Assuntos
Águas Residuárias , Purificação da Água , Destilação , Filtração , Membranas Artificiais , Osmose , Diálise Renal
2.
Pharmacology ; 103(5-6): 320-323, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30889613

RESUMO

BACKGROUND: Nasal carriage of Staphylococcus aureus is very common among health care workers, and treatment with mupirocin is one of the choicest antibiotics available. But with the rampant usage of mupirocin like other antibiotics, the emergence of mupirocin resistance is also on rise. This resistance is both low level as well as high level among the isolated strains. AIM: To screen for the high-level mupirocin resistance among the isolated Staphylococcus strains by Kirby Bauer disk diffusion method. MATERIALS AND METHODS: A total of 200 clinical isolates were tested for high level mupirocin resistance by disk diffusion method using Himedia disks. RESULTS: Among the 200 nasal swabs, 26 (13%) showed growth of S. aureus, whereas 174 (87%) showed the growth of coagulase negative staphylococcus (CONS) spp. Mupirocin resistance was observed only among CONS spp, which was 15% for low-level mupirocin and 8% for high-level mupirocin resistance. No mupirocin resistance was observed among the Staphylococcus spp. CONCLUSION: The identification of Mupirocin resistance will guide us to utilize the antibiotic in a judicious way to treat the nasal carriage effectively.


Assuntos
Antibacterianos/farmacologia , Mupirocina/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus/efeitos dos fármacos , Antibacterianos/administração & dosagem , Portador Sadio/microbiologia , Estudos Transversais , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Bacteriana , Feminino , Pessoal de Saúde , Humanos , Masculino , Mupirocina/administração & dosagem , Cavidade Nasal/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus/enzimologia , Staphylococcus/isolamento & purificação
3.
J Lab Physicians ; 11(4): 300-304, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31929694

RESUMO

BACKGROUND: Handwashing is the most important daily activity to keep microbial infections at a distance. Schoolchildren tend to acquire most of the infections by not following the protocol of frequent handwashing which leads to frequent illnesses and absenteeism from school on a regular basis. MATERIALS AND METHODS: A cross-sectional study was conducted by means of collecting hand swabs from 133 schoolchildren to estimate the extent of germs present. Furthermore, student's perception on hand hygiene was assessed by means of questionnaire. RESULTS: Among the schoolchildren, majority (68.4%) of them felt washing hands is important. Almost 56.4% of students washed their hands before eating lunch, but only 64.7% of them used soaps for cleaning their hands. Furthermore, hand swabs of 133 schoolchildren showed the growth of potential pathogens such as Staphylococcus aureus, Escherichia coli, Klebsiella spp., and Enterococcus faecalis. CONCLUSIONS: Hands of schoolchildren were found to be contaminated and measures to inculcate the habit of frequent handwashing with soap are essential.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 135: 1123-36, 2015 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-25189524

RESUMO

New nonlinear optical crystal, (E)-N'-(4-Methoxybenzylidene)pyridine-3-carbohydrazide dihydrate (MBP3CD 2H2O) has been synthesized and grown as a single crystal by the slow evaporation solution growth technique. The compound was characterized by FTIR (4000-400 cm(-1)), FT-Raman (3500-50 cm(-1)) and UV-Vis (800-200 nm) spectroscopy. The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of MBP3CD 2H2O have been investigated experimentally and theoretically using Gaussian03 software package were performed using B3LYP method with the 6-31G(d,p) basis set. Stability of the molecule arising from hyperconjugative interactions, charge delocalization have been analyzed using Natural Bond Orbital (NBO) analysis. The calculated first hyperpolarizability is comparable with the reported values of similar derivatives and is an attractive object for future studies of nonlinear optics. The HOMO and LUMO analysis is used to determine the charge transfer within the molecule. In addition, molecular electrostatic potential (MEP), frontier molecular orbital (FMO) analysis were investigated using theoretical calculations. The chemical reactivity and thermodynamic properties (heat capacity, entropy and enthalpy) of MBP3CD 2H2O at different temperature are calculated.


Assuntos
Hidrazinas/química , Hidrazinas/síntese química , Modelos Moleculares , Piridinas/química , Piridinas/síntese química , Teoria Quântica , Elétrons , Conformação Molecular , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Eletricidade Estática , Termodinâmica , Vibração
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 138: 271-82, 2015 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-25498824

RESUMO

The organic compound 1-(pyrazin-2-yl) piperidin-2-ol (abbreviated as PPOL) has been synthesized and characterized by IR, Raman, (1)H NMR and UV-Vis spectroscopy. The Fourier-transform Raman (3500-50cm(-1)) and infrared spectra (4000-400cm(-1)) were recorded in the solid state and interpreted by comparison with theoretical spectra derived from density functional theory (DFT) calculations. The optimized geometry, frequency and intensity of the vibrational bands of the compound was obtained by the density functional theory using 6-31G(d,p) basis set. In the optimized geometry results shows that geometry parameters are good agreement with XRD values. Stability of the molecule arising from hyper conjugative interactions, charge delocalization has been analyzed using natural bond orbital (NBO) analysis. In calculation of electronic absorption spectra, TD-DFT calculations were carried out in the both gas and solution phases. (1)H NMR chemical shifts were calculated by using the gauge-invariant atomic orbital (GIAO) method. (1)H NMR analysis is evident for O-H⋯O intermolecular interaction of the title molecule. The thermodynamic properties of the title compound have been calculated at different temperatures and the results reveal that the standard heat capacities (Cp,m), standard entropies (Sm) and standard enthalpy changes (Hm) increase with rise in temperature. In addition, HOMO and LUMO energies and the first-order hyperpolarizability have been computed.


Assuntos
Espectroscopia de Ressonância Magnética , Piperidinas/síntese química , Pirazinas/química , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Algoritmos , Gases , Hidrogênio/química , Oxigênio/química , Piperidinas/química , Software , Temperatura , Termodinâmica , Vibração
6.
Indian J Hematol Blood Transfus ; 30(Suppl 1): 258-63, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25332593

RESUMO

Alkylating agents used in chemotherapy are mutagenic and have strong leukemogenic potential. The most serious long term complication of chemotherapy is the development of secondary disease, particularly hematological malignancy; they have rarely been reported in the context of ovarian cancer treatment. We describe quite a rare occurrence of a myelodyplastic/myeloproliferative neoplasm, unclassified (MDS/MPN-U) with acute leukemic transformation and multiple cytogenetic abnormalities not usually found together as JAK2 V617F mutation, 5q- and 7q-deletion, after exposure to paclitaxel and carboplatin based chemotherapy in a patient treated for ovarian cancer. We should be aware of such complication whose prognosis is really poor.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 133: 799-810, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-25000567

RESUMO

The Fourier transform infrared (4000-400cm(-1)) and Fourier transform Raman (3500-50cm(-1)) spectra of 4-Chloro-dl-phenylalanine (4CLPA) were recorded and analyzed. The equilibrium geometry, bonding features and harmonic vibrational wavenumbers were investigated with the help of density functional theory (DFT) method using B3LYP/6-31G(d,p) as basis set. The observed vibrational wavenumbers were compared with the calculated results. Natural bond orbital analysis confirms the presence of intramolecular charge transfer and the hydrogen bonding interaction. Predicted electronic absorption spectra from TD-DFT calculation have been analyzed comparing with the UV-Vis (200-800nm) spectrum. The effects of chlorine and ethylene group substituent in benzene ring in the vibrational wavenumbers have been analyzed. The HOMO-LUMO energy gap explains the charge interaction taking place within the molecule. The first order hyperpolarizability (ß0) and related properties (ß, α0 and Δα) of 4CLPA were calculated. The Chemical reactivity and chemical potential of 4CLPA is calculated. In addition, molecular electrostatic potential (MEP), frontier molecular orbital (FMO) analysis were investigated using theoretical calculations.


Assuntos
Fenilalanina/química , Halogenação , Modelos Moleculares , Teoria Quântica , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 133: 417-31, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-24973782

RESUMO

In this study sulfonamide compound, N-phenylbenzenesulfonamide (NPBS) has been synthesized and grown as a high quality single crystal by the slow evaporation solution growth technique. The grown crystals were characterized by the Fourier transform infrared (4000-400cm(-1)), Fourier transform Raman (3500-500cm(-1)), UV-Vis (200-800nm) and NMR spectroscopy. Density functional (DFT) calculations have been carried out for the compound NPBS by utilizing DFT level of theory using B3LYP/6-31G(d,p) as basis set. The theoretical vibrational frequencies and optimized geometric parameters such as bond lengths and bond angles have been calculated by using quantum chemical methods. The stability of the molecule arising from hyper conjugative interaction and charge delocalization has been analyzed using NBO analysis. The dipole moment, linear polarizability and first order hyperpolarizability values were also computed. The chemical reactivity and ionization potential of NPBS were also calculated. In addition, Molecular Electrostatic Potential (MEP), Frontier Molecular Orbital (FMO) analysis was investigated using theoretical calculations. The thermodynamic properties of the compound were calculated at different temperatures and corresponding relations between the properties and temperature were also studied. Finally, geometric parameters, vibrational bands were compared with available experimental data of the molecules.


Assuntos
Derivados de Benzeno/química , Sulfonamidas/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Teoria Quântica , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 127: 498-510, 2014 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-24657932

RESUMO

In this study, geometrical optimization, spectroscopic analysis, electronic structure and nuclear magnetic resonance studies of (S)-(-)-N-(5-Nitro-2-pyridyl) alaninol (abbreviated as SN5N2PLA) were investigated by utilizing HF and DFT/B3LYP with 6-31G(d,p) as basis set. The Fourier transform infrared (FT-IR) and FT-Raman spectra of SN5N2PLA were recorded in the region 4000-400cm(-1) and 3500-50cm(-1), respectively. Complete vibrational assignments, analysis and correlation of the fundamental modes for the title compound were carried out. UV-Visible spectrum of the compound that dissolved in methanol were recorded in the region 200-800nm and the electronic properties HOMO and LUMO energies were measured by TD-DFT approach. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. The molecular stability and bond strength have been investigated by applying the Natural Bond Orbital (NBO) analysis. The (1)H and (13)C nuclear magnetic resonance (NMR) chemical shifts of SN5N2PLA were calculated using the GIAO method in methanol solution and compared with the measured experimental data. The dipole moment, polarizability and first order hyperpolarizability values were also computed. The polarizability and first hyperpolarizability of the studied molecule indicate that the compound is a good candidate of nonlinear optical materials. The Chemical reactivity and Thermodynamic properties of SN5N2PLA at different temperature are calculated. In addition, molecular electrostatic potential (MEP), frontier molecular orbitals (FMOs) analysis were investigated using theoretical calculations.


Assuntos
Modelos Químicos , Modelos Moleculares , Propanolaminas/química , Estrutura Molecular , Análise Espectral , Termodinâmica
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 122: 130-41, 2014 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-24299985

RESUMO

In this study, geometrical optimization, spectroscopic analysis, electronic structure and nuclear magnetic resonance studies of 4-Methoxy-4'-Nitrobiphenyl (abbreviated as 4M4'NBPL) were investigated by utilizing HF and DFT/B3LYP with 6-31G(d,p) as basis set. The equilibrium geometry, vibrational wavenumbers and the first order hyperpolarizability of the 4M4'NBPL have been calculated with the help of density functional theory computations. The FT-IR and FT-Raman spectra were recorded in the region 4000-400 cm(-1) and 3500-50 cm(-1) respectively. Natural Bond Orbital (NBO) analysis is also used to explain the molecular stability. The UV-Vis absorption spectra of the title compound dissolved in chloroform were recorded in the range of 200-800 cm(-1). The HOMO-LUMO energy gap explains the charge interaction taking place within the molecule. Good correlation between the experimental (1)H and (13)C NMR chemical shifts in chloroform solution and calculated GIAO shielding tensors were found. The dipole moment, linear polarizability and first order hyperpolarizability values were also computed. The linear polarizability and first order hyperpolarizability of the studied molecule indicate that the compound is a good candidate of nonlinear optical materials. The chemical reactivity and thermodynamic properties of 4M4'NBPL at different temperature are calculated. In addition, molecular electrostatic potential (MEP), frontier molecular orbitals (FMO) analysis were investigated using theoretical calculations.


Assuntos
Compostos de Anilina/química , Compostos de Bifenilo/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Teoria Quântica , Análise Espectral Raman , Vibração , Conformação Molecular , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termodinâmica
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 77(3): 612-9, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20650677

RESUMO

In this work, we report anharmonic vibrational frequencies, molecular structure, NBO and HOMO, LUMO analysis of naphthalene acetic acid (NAA). The optimized geometric bond lengths and bond angles obtained by computation show good agreement with experimental X-ray data. The computed dimer parameters also show good agreement with experimental data. Anharmonic frequencies of NAA were determined and analyzed by DFT level of theory utilizing 6-311+G(d,p) basis set. Good agreement between the calculated and experimental spectra was obtained. Stability of the molecule arising from hyperconjugative interactions and charge delocalization have been analyzed using natural bond orbital (NBO) analysis. The results show that charge in electron density (ED) in the pi* and sigma* antibonding orbitals and E2 energies. This confirms the occurrence of ICT (Intermolecular Charge Transfer) within the molecule. The calculated HOMO and LUMO energies also show that charge transfer occurs within the molecule.


Assuntos
Modelos Químicos , Ácidos Naftalenoacéticos/química , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Dimerização , Ligação de Hidrogênio , Modelos Moleculares , Estrutura Molecular , Vibração
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 74(3): 788-97, 2009 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19729338

RESUMO

In the present study, structural properties of 3,5-dimethylpyrazole (3,5-DMP) have been studied extensively utilizing density functional theory (DFT) employing B3LYP exchange correlation. The Fourier transform infrared (solid phase and gas phase) and Fourier transform Raman spectra of 3,5-DMP were recorded. The Vibrational frequencies of 3,5-DMP in the ground state have been calculated by using density functional method (B3LYP) with 6-31G(d,p), 6-311G(d,p) and 6-311++G(d,p) as basis sets. Comparison of the observed fundamental vibrational frequencies of 3,5-DMP with calculated results show that 6-311++G(d,p) superior to other basis sets for molecular vibrational problems. Non linear optical NLO behavior of the examined molecule was investigated by the determination of the electric dipole moment mu, the polarizability alpha and the hyperpolarizability beta using the B3LYP/cc-pvdz method. The isotropic chemical shifts computed by (13)C and (1)H NMR analysis also show good agreement with experimental observations. The theoretically predicted FTIR and FT-Raman spectra of the title molecule have been constructed.


Assuntos
Pirazóis/análise , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
13.
J Environ Sci Eng ; 49(4): 259-64, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18476372

RESUMO

Anaerobic digestion of vegetable waste slurry carried out in the laboratory using 2.5L capacity bottle reactors for 60 days at ambient temperature conditions resulted in a biogas yield of 0.391 L/g of VS fed. The methane content of the biogas generated from the reactors was in the range of 67%-70%. The biochemical methane potential obtained from the laboratory was 0.269 L CH4/g VS added.


Assuntos
Reatores Biológicos , Carbono/análise , Metano/análise , Piretrinas/análise , Eliminação de Resíduos/métodos , Adsorção , Biodegradação Ambiental , Físico-Química/métodos , Concentração de Íons de Hidrogênio , Cinética , Praguicidas , Propriedades de Superfície , Fatores de Tempo , Verduras , Eliminação de Resíduos Líquidos
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