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1.
Environ Sci Technol ; 52(21): 12642-12648, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30335978

RESUMO

Coagulation is an important process to remove organics from water. The molecular composition and structure of organic matter influence water quality in many ways, and the lack of information regarding the organics removed by different coagulants makes it challenging to optimize coagulation processes and ensure reclaimed water safety. In this paper, we investigated coagulation of secondary biological effluent from a municipal sewage treatment plant with different coagulants. We emphasized investigation of organics removal characteristics at the molecular level using Fourier transform-ion cyclotron resonance mass spectrometry (FT-ICR MS) coupled with electrospray ionization (ESI). We found that conventional coagulants can only partially remove condensed polycyclic aromatics and polyphenols with low H/C (H/C < 0.7) and highly unsaturated and phenolic compounds and aliphatic compounds with high O/C (O/C > 0.6). A new coagulant, CBHyC, had better removal efficiencies for all organics with different element compositions and molecular structures, especially organics that are resistant to conventional coagulants such as highly unsaturated and phenolic compounds and aliphatic compounds located in 0.3 < O/C < 0.8 and 1.0 < H/C < 2.0 regions and sulfur-containing compounds with higher O/C (e.g., anionic surfactants and their metabolites or coproducts). This study provides molecular insights into the organics removed by different coagulants and provides data supporting the possible optimization of advanced wastewater treatment processes.


Assuntos
Esgotos , Purificação da Água , Espectrometria de Massas , Águas Residuárias , Água
2.
Chemistry ; 18(9): 2639-45, 2012 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-22282407

RESUMO

Palladium is a key catalyst invaluable to many industrial processes and fine-chemical synthesis. Although recent progress has allowed the synthesis of Pd nanoparticles with various shapes by using different techniques, the facile synthesis of Pd nanocrystals and turning them into a highly active, selective, and stable catalyst systems still remain challenging. Herein, we report the highly selective one-pot synthesis of monodisperse Pd cluster nanowires in aqueous solution; these consist of interconnected nanoparticles and may serve as highly active catalysts because of the enrichment of high index facets on the surface, including {443}, {331}, and {221} steps. For the first time, carbon nanotube and γ-Al(2)O(3) immobilized Pd cluster nanowires showed highly enhanced catalytic performance in the liquid-phase selective hydrogenation of cinnamaldehyde and gas-phase hydrogenation of 1,3butadiene relative to immobilized Pd icosahedra and nanocubes, as well as commercial Pd catalysts.


Assuntos
Nanopartículas/química , Nanofios/química , Paládio/química , Catálise , Hidrogenação , Nanotecnologia , Propriedades de Superfície
3.
Chem Soc Rev ; 40(7): 3802-23, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21412560

RESUMO

This critical review provides a critical discussion of the current state of knowledge of the key factors influencing the solubility of gases in ionic liquids (ILs), including sample purity, experimental methodology, "molecular" characteristics of ILs, temperature and pressure. The review starts with a brief introduction to the current developments and the existing problems in the studies of the gas solubility in ILs. Then, the experimental, computational and theoretical developments in conformational equilibria of ions, in nanosegregated polar and nonpolar domains in ILs, and in the mechanisms for dissolution of gases in ILs are discussed and subsequently collaborated together with our freeze-fracture transmission electron microscopic and Raman measurements to propose the new microscopic mechanism for dissolving the gases in ILs. Next, a critical and quantitative analysis of the influences of the sample purity and the experimental methodology on the gas solubility is made so that the "real" relationships between structure and solubility property can be revealed. In addition, a systematic and deeper understanding of how the "molecular" features of the ILs, the temperature, and the pressure influence the gas solubility is provided at the molecular level. In the section of concluding remarks, the comments are made on the molecular criteria for the future design of the ILs to enhance the gas solubility by specifically optimizing the molecular characteristics of the ILs (265 references).

4.
Zhongguo Zhen Jiu ; 41(7): 725-9, 2021 Jul 12.
Artigo em Chinês | MEDLINE | ID: mdl-34259402

RESUMO

OBJECTIVE: To observe the effect of intradermal needling combined with heat-sensitive moxibustion for moderate to severe cancer pain. METHODS: A total of 60 patients with moderate to severe cancer pain were randomly divided into an observation group and a control group,30 cases in each one. In the control group,opioids were taken to relief pain according to the three-step analgesic method of World Health Organization. On the base of the treatment as the control group, intradermal needling combined with heat-sensitive moxibustion were applied at Neiguan (PC 6), Hegu (LI 4), Zusanli (ST 36), Taichong (LR 3), etc. in the observation group, 14 days of treatment were required. The equivalent morphine consumption at the first day and whole course, the scores of cancer quality of life questionnaire-C30 (QLQ-C30) and Hamilton anxiety scale before and after treatment, and the adverse reaction rate were compared in the two groups. The total analgesic effective rate was evaluated. RESULTS: The total analgesic effective rate was 93.3% (28/30) in the observation group, higher than 73.3% (22/30) in the control group (P<0.05). The total equivalent morphine consumption in the observation group was less than the control group (P<0.05). After treatment, the QLQ-C30 scores were increased (P<0.001) and the HAMA scores were decreased (P<0.001) in the both groups, and those in the observation group were superior to the control group (P<0.001). The adverse reaction rates of fatigue, dizziness, nausea and vomiting, constipation in the observation group were lower than the control group (P<0.05). CONCLUSION: Intradermal needling combined with heat-sensitive moxibustion can reduce the dose of opioids, improve the quality of life, relief the anxiety in patients with moderate to severe cancer pain, and reduce the incidence of common adverse reaction of opioids.


Assuntos
Dor do Câncer , Moxibustão , Neoplasias , Pontos de Acupuntura , Dor do Câncer/terapia , Temperatura Alta , Humanos , Neoplasias/complicações , Neoplasias/terapia , Dor , Qualidade de Vida , Resultado do Tratamento
5.
Zhonghua Jie He He Hu Xi Za Zhi ; 33(5): 344-9, 2010 May.
Artigo em Chinês | MEDLINE | ID: mdl-20646612

RESUMO

OBJECTIVE: To discuss the influence of chronic intermittent hypoxia and secundum oxidative stress on insulin resistance and the function of Pancreatic beta cells in OSAHS patients. METHODS: 15 patients with primary snoring, 31 patients with light to moderate OSAHS and 34 patients with severe OSAHS were investigated. General clinical data of every patient were collected, while nocturnal data were gained by using PSG with entire night monitor. 8-isoprostane and fasting insulin (FINS) were detected through ELISA; GSH-Px through Spectrophotometer. Insulin resistance was evaluated by measuring HOMA-IR and FINS, while the function of Pancreatic beta cells by HOMA-beta. The comparison among the three groups were used by the non-parametric Kruskal-Wallis H test, and Nemenyi test was used for pairwise comparison. The relativity between the variables were assessed by Spearman correlation test, and multiple linear regression was used to remove interference between variables. The enumeration data were compared with chi2 test. RESULTS: 1. Along with the aggravation of OSAHS, the three groups were statistically different from each other on 8-isoprostane, GSH-Px, fasting blood glucose (FBG), FINS, and HOMA-IR (P=0.0034, P<0.0001), but not on HOMA-beta (P>0.05). 2. ODI, CT90%, lowest SaO2 and mean SaO2 were correlated with FINS and HOMA-IR in the serum, while the coefficient of correlation r decreased from ODI to mean SaO2. After ruling out the influence of age, BMI by multiple linear regression, ODI, CT90% and lowest SaO2 still correlated with FINS and HOMA-IR, the standardized regression coefficient R diminished from ODI, CT90% to lowest SaO2. 3. 8-isoprostane and GSH-Px correlated with FINS and HOMA-IR in OSAHS patients (P<0.05). After eliminated the influence of age, BMI by multiple linear regression, 8-isoprostane still correlated with FINS and HOMA-IR. 4. HOMA-beta has no correlation with AHI, BMI, ODI, CT90%, lowest SaO2, mean SaO2, 8-isoprostane and GSH-Px (P>0.05). CONCLUSION: 1. Chronic intermittent hypoxia of OSAHS was independently correlated with IR. Compared with the severity of hypoxia, the insulin resistance has a closer relation with oxygen desaturation index. 2. Secundum oxidative stress in OSAHS was independently correlated with IR. 3. We didn't find the function of Pancreatic beta cells correlating with chronic intermittent hypoxia and secundum oxidative stress.


Assuntos
Hipóxia , Insulina/metabolismo , Apneia Obstrutiva do Sono/metabolismo , Feminino , Humanos , Resistência à Insulina , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/fisiologia , Masculino , Estresse Oxidativo , Apneia Obstrutiva do Sono/fisiopatologia , Ronco/fisiopatologia
6.
Materials (Basel) ; 10(6)2017 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-28772992

RESUMO

Friction and wear behavior exists between hoisting ropes that are wound around the drums of a multi-layer winding hoist. It decreases the service life of ropes and threatens mine safety. In this research, a series of experiments were conducted using a self-made test rig to study the effects of the strand lay direction and crossing angle on the winding rope's tribological behavior. Results show that the friction coefficient in the steady-state period shows a decreasing tendency with an increase of the crossing angle in both cross directions, but the variation range is different under different cross directions. Using thermal imaging, the high temperature regions always distribute along the strand lay direction in the gap between adjacent strands, as the cross direction is the same with the strand lay direction (right cross contact). Additionally, the temperature rise in the steady-state increases with the increase of the crossing angle in both cross directions. The differences of the wear scar morphology are obvious under different cross directions, especially for the large crossing angle tests. In the case of right cross, the variation range of wear mass loss is larger than that in left cross. The damage that forms on the wear surface is mainly ploughing, pits, plastic deformation, and fatigue fracture. The major wear mechanisms are adhesive wear, and abrasive and fatigue wear.

7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(10): 1606-9, 2005 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-16395894

RESUMO

Clays such as kaolinite and montmorillonite, are commonly used as an additive to modify the thermal properties of polymer. In the present work, the morphology, composition, shape and structure of montmorillonite and kaolinite were characterized and compared by various advanced techniques. The TEM/EDX data showed that the kaolinite has a larger particle size and a lower Si/Al ratio than montmorillonite. These clays were stacked by platelets. The TGA results revealed that montmorillonite loses significant weight (around 7%) from 60 to 90 degrees C due to the dehydration of absorbed water, however, kaolinite almost doesn't lose weight in this temperature range. Kaolinites loses its weight because of the loss of its structural OH groups at a lower temperature (around 510 degrees C) than montmorillonite (670 degrees C). The PAS-FTIR spectra showed that montmorillnite has a strong absorbance of hydroxyl group in hydrogen bond region at room temperature, which presents a strong ability to adsorb water on its surface. The results of varied infrared temperature and TGA showed that their structural OH group is very stable from 100 to 500 degrees C, and it is possible to form thermosetting PU/PLS composite by reaction with the isocynate group of polyurethane prepolymer.

8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(9): 1066-8, 2004 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-15762523

RESUMO

The samples of PUU polymers were characterized by In-situ FTIR in a temperature-controlled cell. The spectra of FTIR showed that the absorbance of ordered hydrogen-bonded urea carbonyl group (1643 cm(-1)) became stronger with increasing thermal process time (at 100 degrees C), then changed little after a certain time. The rate of change for absorbance of ordered hydrogen-bonded urea link, attributed to microphase separation kinetics, was enhanced with increasing thermal process temperature. In carbonyl region of FTIR spectra, absorbance for various carbonyls available in PUU polymers, associated with micro-hard domain, was observed before process. However, after the process, only the absorbance of free urethane, hydrogen-bonded urethane and ordered urea became obvious. At 100 degrees C, the longer the process time (beyond 8 h), the worse the mechanical properties obtained. The PUU polymers processed at 100 degrees C with the identical process time exhibited the best mechanical properties.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 22(5): 774-8, 2002 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-12938427

RESUMO

The development of morphology and mechanical properties of PUU in bulk prepolymer polymerization process was investigated by TEM and in situ FTIR. The data from the FTIR spectra showed that the absorbance of NH band was becoming sharp and its band sites shifted to lower wavenumbers with the increase of reaction time, the absorbance of free urethance carbonyl kept nearly constant at low conversion, and then became weaker, and finally became little because of strong hydrogen bond affect of more and more new wrealink group at high conversion. With increasing of the reaction time, the band sites of urea carbonyl also shifted to the lower wavenumbers and at the same time, the absorbance of ordered urea carbonyl became sharper and sharper. The carbonyl bands vibration models available during curing process were further assigned. The photos of TEM showed that the domains of hard segments became clearer with buildup of hydrogen bond between urealinks.


Assuntos
Poliuretanos/química , Reagentes de Ligações Cruzadas , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Propriedades de Superfície , Vibração
10.
PLoS One ; 8(9): e74479, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24058573

RESUMO

BACKGROUND: Hybridization between genetically diverged organisms is known as an important avenue that drives plant genome evolution. The possible outcomes of hybridization would be the occurrences of genetic instabilities in the resultant hybrids. It remained under-investigated however whether pollination by alien pollens of a closely related but sexually "incompatible" species could evoke genomic changes and to what extent it may result in phenotypic novelties in the derived progenies. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we have re-sequenced the genomes of Oryza sativa ssp. japonica cv. Matsumae and one of its derived introgressant RZ35 that was obtained from an introgressive hybridization between Matsumae and Zizanialatifolia Griseb. in general, 131 millions 90 base pair (bp) paired-end reads were generated which covered 13.2 and 21.9 folds of the Matsumae and RZ35 genomes, respectively. Relative to Matsumae, a total of 41,724 homozygous single nucleotide polymorphisms (SNPs) and 17,839 homozygous insertions/deletions (indels) were identified in RZ35, of which 3,797 SNPs were nonsynonymous mutations. Furthermore, rampant mobilization of transposable elements (TEs) was found in the RZ35 genome. The results of pathogen inoculation revealed that RZ35 exhibited enhanced resistance to blast relative to Matsumae. Notably, one nonsynonymous mutation was found in the known blast resistance gene Pid3/Pi25 and real-time quantitative (q) RT-PCR analysis revealed constitutive up-regulation of its expression, suggesting both altered function and expression of Pid3/Pi25 may be responsible for the enhanced resistance to rice blast by RZ35. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that introgressive hybridization by Zizania has provoked genomewide, extensive genomic changes in the rice genome, and some of which have resulted in important phenotypic novelties. These findings suggest that introgressive hybridization by alien pollens of even a sexually incompatible species may represent a potent means to generate novel genetic diversities, and which may have played relevant roles in plant evolution and can be manipulated for crop improvements.


Assuntos
Variação Genética , Genoma de Planta/genética , Endogamia , Oryza/genética , Análise de Sequência de DNA/métodos , Pareamento de Bases/genética , Cromossomos de Plantas/genética , Simulação por Computador , Elementos de DNA Transponíveis/genética , DNA de Plantas/genética , Resistência à Doença/genética , Resistência à Doença/imunologia , Genes de Plantas/genética , Homozigoto , Mutação/genética , Nucleotídeos/genética , Fenótipo , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Polimorfismo de Nucleotídeo Único/genética , Reprodutibilidade dos Testes
11.
Nanoscale ; 4(8): 2633-9, 2012 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-22402765

RESUMO

Pt-Pd bimetallic alloy nanostructures with highly selective morphologies such as cube, bar, flower, concave cube, and dendrite have been achieved through a facile one-pot solvothermal synthesis. The effects of shape-controllers (sodium dodecyl sulfate (SDS), ethylenediamine-tetraacetic acid disodium salt (EDTA-2Na), NaI) and solvents (water/DMF) on the morphologies were systematically investigated. The electrocatalytic activities of these Pt-Pd alloy nanostructures toward formic acid oxidation were tested. The results indicated that these alloy nanocrystals exhibited enhanced and shape-dependent electrocatalytic activity toward formic acid oxidation compared to commercial Pt black and Pt/C catalysts.

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