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1.
Reprod Fertil ; 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38064285

RESUMEN

We aim to investigate the correlation of the position of the transferred air bubble with the clinical pregnancy rate (PR) in frozen-thawed embryo transfer(FET) cycles. A prospective clinical study was carried out at Reproductive medicine center of West China Second University Hospital between June 2020 and May 2021. 1159 women underwent FET were included in this study. Transabdominal ultrasonographic guidance was used during the transfer procedure. The distance from the air bubble to endometrial cavity fundus(DAF)was measured in the freeze-frame ultrasound immediately after ET. In group DAF ≤3mm, 3-15mm and ≥15mm, the clinical PR in women transferred with cleavage embryos were 33.3% (7/21), 55.0% (153/280), and 31.3% (5/16), respectively, the difference was statistically significant (P<0.05). Among women transferred with blastocysts, the clinical PR was 63.0% (34/54), 68.5% (485/708) and 55.0% (44/80), respectively, the difference was statistically significant (P<0.05). In multivariate logistic regression model for clinical PR, the clinical PR was associated with age, embryo quality, number of embryo transferred, and endometrial thickness. DAF was an independent risk factor influencing clinical PR in blastocysts FET cycles rather than in cleavage embryos FET cycles.In conclusion, our results suggested that DAF was associated with the clinical PR and DAF between 3mm and 15mm is the optimal position in blastocysts FET cycles.

2.
J Hazard Mater ; 448: 130995, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-36860061

RESUMEN

In order to solve the problem of easy aggregation of copper oxides in environmental remediation, it is an effective method to confine copper oxides to suitable substrates. Herein, we design a novel Cu2O/Cu@MXene composite with a nanoconfinement structure, and it can effectively activate peroxymonosulfate (PMS) to produce .OH for degradation tetracycline (TC). Results indicated that the MXene with extraordinary multilayer structure and surface negativity could fix the Cu2O/Cu nanoparticles in the layer spaces and suppress the agglomeration of nanoparticles. The removal efficiency of TC reached 99.14 % within 30 min, and the pseudo-first-order reaction kinetic constant was 0.1505 min-1, which was 3.2 times that of Cu2O/Cu alone. The outstanding catalytic performance attributed that the MXene based on Cu2O/Cu@MXene could promote the adsorption of TC and electron transmittal between Cu2O/Cu nanoparticles. Furthermore, the degradation efficiency of TC was still over 82 % after five cycles. In addition, based on the degradation intermediates provided by LC-MS, two specific degradation pathways were proposed. This study provides a new reference for suppressing the agglomeration of nanoparticles, and broadens the application of MXene materials in the field of environmental remediation.

3.
J Hazard Mater ; 435: 128958, 2022 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-35472553

RESUMEN

Non-radical oxidation pathways in the Fenton-like process have a superior catalytic activity for the selective degradation of organic contaminants under complicated water matrices. Whereas the synthesis of high-performance catalysts and research on reaction mechanisms are unsatisfactory. Herein, it was the first report on copper-cobalt selenide (CuCoSe) that was well-prepared to activate hydrogen peroxide (H2O2) for non-radical species generation. The optimized CuCoSe+H2O2 system achieved excellent removal of chlortetracycline (CTC) in 10 min at neutral pH along with pleasing reusability and stability. Moreover, it exhibited great anti-interference capacity to inorganic anions and natural organic matters even in actual applications. Multi-surveys verified that singlet oxygen (1O2) was the dominant active species in this reaction and electron transfer on the surface-bound of CuCoSe and H2O2 likewise played an important role in direct CTC oxidation. Where the synergetic metals of Cu and Co accounted for the active sites, and the introduced Se atoms accelerated the circulation efficiency of Co3+/Co2+, Cu2+/Cu+ and Cu2+/Co2+. Simultaneously, the produced Se/O vacancies further facilitated electron mediation to enhance non-radical behaviors. With the aid of intermediate identification and theoretical calculation, the degradation pathways of CTC were proposed. And the predicted ecotoxicity indicated a decrease in underlying environmental risk.


Asunto(s)
Cobre , Peróxido de Hidrógeno , Catálisis , Cobalto , Cobre/química , Peróxido de Hidrógeno/química , Oxidación-Reducción
4.
J Colloid Interface Sci ; 610: 751-765, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-34857379

RESUMEN

Fenton-like catalysts have usually superior catalytic activities, however, some drawbacks of ion leaching and difficult-to-recovery limit their applications. In this work, a hierarchical porous Fe3O4/Co3S4 catalyst was fabricated via a simple phase change reaction to overcome these shortcomings. The introduced iron cooperates with cobalt achieving high-efficiency activation of peroxymonosulfate (PMS) to eliminate Rhodamine B (RhB). The results showed that 0.05 g/L Fe3O4/Co3S4 and 1 mM PMS could quickly remove 100% of 200 mg/L RhB within 20 min, and the removal rate of RhB remained above 82% after 5 cycles. Moreover, the as-prepared Fe3O4/Co3S4 possessed a great magnetic separation capacity and good stability of low metal leaching dose. Radical quenching experiments and electron paramagnetic resonance (EPR) techniques proved that sulfate radicals (SO4•-) were the dominant reactive oxygen species responding for RhB degradation. X-ray photoelectron spectroscopy (XPS) pointed out that the synergism of sulfur promoted the cycling of Co3+/Co2+ and Fe3+/Fe2+, boosting the electron transfer between Fe3O4/Co3S4 and PMS. Moreover, the degradation pathways of RhB were deduced by combining liquid chromatography-mass spectrometry (LC-MS) analysis and density functional theory (DFT) calculations. The toxicities of RhB and its intermediates were evaluated as well, which provided significant assistance in the exploration of their ecological risks.


Asunto(s)
Peróxidos , Porosidad , Rodaminas
5.
J Colloid Interface Sci ; 597: 56-65, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33862447

RESUMEN

The use of single-atom iron catalysts in heterogeneous Fenton-like reactions has demonstrated tremendous potential for antibiotic wastewater treatment. In this study, single-atom iron fixed on nitrogen-doped porous carbon materials (Fe-ISAs@CN) was synthesised using a metal organic framework (MOF) as a precursor. Fe-ISAs@CN was applied as a heterogeneous Fenton catalyst to activate H2O2 for the degradation of sulfadiazine (SDZ) in an aqueous solution. The physical and chemical properties of Fe-ISAs@CN were characterised by scanning electron microscopy (SEM), transmission electron microscope (TEM), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and rotating disk electrode (RDE) measurements. The results of our degradation experiments indicated that Fe-ISAs@CN exhibited remarkable activity and stability for the degradation of SDZ over a wide pH range; even after five cycles, Fe-ISAs@CN retained a high catalytic efficiency (>80%). The 5,5-dimethyl-1-oxaporphyrin-n-oxide (DMPO)-X signal captured by electron paramagnetic resonance (EPR) spectroscopy indicated that a large amount of hydroxyl radicals (OH) was produced in the reaction system. Quench tests indicated that the OH was the main active substance in the degradation of SDZ. The degradation products of the reaction were analysed by High Performance Liquid Chromatography-Mass Spectrometry (HPLC-MS), and possible degradation pathways for the SDZ degradation were proposed.

6.
J Colloid Interface Sci ; 578: 304-314, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32531560

RESUMEN

Helical carbon fibers (HCFs) are a new kind of fascinating carbon material, and have caused much attention for their distinctive features, diversified novel properties, and applications. However, the application of HCFs still faces a series of barriers, especially in the repetitive preparation of HCFs. In this paper, we initially report the synthesis of the HCFs with ultrahigh specific surface area (3089 m2 g-1) by a bio-template process using the high purified spiral vessels (SVs) as the template. The helical structure with the ultrahigh specific surface area can efficaciously shorten the pathway for antibiotics diffusion, and the high content of nanopores (1 to 3 nm) not only guarantees the accessibility of the surface for antibiotics storage but also easily provides approachable channels for antibiotics transmission. The highest adsorption capacity for sulfamethoxazole (SMX) is 1091 mg/g at pH 6.0 ± 0.1 with a stable temperature of 20 °C when the initial SMX concentration is 80 mg/L. This study motivates a new bio-inspired design for preparing the high purified HCFs with a simple bio-template method. The results show that the porous HCFs are a new kind of ultrahigh adsorption material for the removal of SMX in aqueous solution and can be used in new technological applications.

7.
J Med Screen ; 27(4): 201-206, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-31896295

RESUMEN

OBJECTIVE: Cervical cancer screening participation in China remains insufficient, possibly because of embarrassment or discomfort. We assessed knowledge of HPV and its link to cervical cancer, and whether HPV self-sampling might be an acceptable alternative to clinician-based screening, among Sichuan women. METHODS: A sample of healthy women undergoing routine physical examinations in 2017 at the West China Hospital, Sichuan University, completed a questionnaire. RESULTS: From 3000 questionnaires distributed, 1810 were completed and analyzed. Only 29.94% of respondents (n = 542) had heard of HPV, among whom 65.75% knew that it caused cervical cancer. Among the 766 (42.32%) who considered that HPV self-sampling for cervical cancer screening was an acceptable option, over 90% thought it would be convenient, private, not embarrassing, and not painful. However, 1044 women (57.68%) did not consider self-sampling acceptable, mainly because the result might not be accurate (85.63%), specimens may have gone bad (83.05%), and they may not perform the test correctly (79.98%). Respondents who believed HPV self-sampling was acceptable were more likely than other respondents to be young, and to have completed at least secondary education. Of the 1810 respondents, 1312 (72.49%) reported that they would be willing to be vaccinated against HPV. CONCLUSION: Most women in Chengdu lack basic knowledge about HPV. Over 40% of women believed HPV self-sampling for cervical cancer screening was an acceptable option. To increase screening coverage, public health efforts to educate the public about HPV and HPV self-sampling for cervical cancer screening should be strengthened and expanded.


Asunto(s)
Detección Precoz del Cáncer/métodos , Conocimientos, Actitudes y Práctica en Salud , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/epidemiología , Autocuidado/métodos , Manejo de Especímenes/métodos , Adolescente , Adulto , Anciano , Alphapapillomavirus , China/epidemiología , Estudios Transversales , Femenino , Humanos , Tamizaje Masivo , Persona de Mediana Edad , Prueba de Papanicolaou/estadística & datos numéricos , Aceptación de la Atención de Salud/estadística & datos numéricos , Encuestas y Cuestionarios , Neoplasias del Cuello Uterino/diagnóstico , Adulto Joven
8.
J Colloid Interface Sci ; 562: 1-11, 2020 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-31830627

RESUMEN

In this work, 1D MnO2 nano-needles were prepared and grown on the graphene oxide (GO) nano-sheets successfully. The morphology and structure of materials were explored. The MnO2 nano-needles with a length of 200-400 nm were distributed uniformly on the GO nano-sheets. As a result of GO substrate, the MnO2/GO nano-hybrids (MnO2/GO) have the much larger surface area and more surface oxygen-containing functional groups than MnO2 nano-needles, which are beneficial for enrichment and degradation of the norfloxacin (NOR). Results showed that more than 80% NOR was degraded within 20 min at the dose of 10 mM PMS and 0.8 g/L catalysts. Moreover, the optimal pH in MnO2/PMS and MnO2/GO/PMS system were both acidic condition. Furthermore, the mechanism of PMS activation by MnO2/GO was investigated through radical identification using quenching experiments and EPR techniques. According to this, the HSO5- of PMS reacted with Mn (IV)/Mn(III) to form a redox loop, and GO played an important role in the degradation process. Finally, the transformation intermediates of NOR were identified and four probable degradation pathways were speculated. This work would provide a potential contribution towards NOR removal in the environmental remediation.


Asunto(s)
Grafito/química , Compuestos de Manganeso/química , Modelos Químicos , Nanocompuestos/química , Norfloxacino/química , Óxidos/química , Peróxidos/química
9.
J Environ Manage ; 245: 291-301, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31158681

RESUMEN

Fenton system is one of the most popular methods to eliminate antibiotics and dyes in aquatic environment. However, the existed Fenton system is limited by various factors such as potential second pollution and narrow pH range. In this study, we report that the bottlenecks for high strength antibiotics and dyes wastewater treatment at a wide pH range can be well tackled by the nanoscale "yarn ball"-like Mo/W-containing heteropoly blue (HPB) catalyst Mg2Ti6Mo23O119SiW12 (1). This novel catalyst displayed extremely efficient elimination for several typical organic contaminants such as malachite green (MG), tetracycline (TC) and methyl orange (MO). Compared with other materials reported in previous papers, the catalytic performance of 1 in degradation of the organic contaminants of high concentrations increased several times. More than 90% of antibiotics and dyes are degraded within 60 min. Electron spin resonance (ESR) experiments and UV-vis spectra confirmed that the catalytic mechanisms of 1 could mainly ascribe to the 1/H2O2 process and the possible photocatalytic oxidation of adsorbed H2O by holes (h+) in the valence band (VB) of 1 surface generated ·OH for extremely efficient degradation of organic contaminants. This work widens the optimal pH values up to neutral condition and it's significant for the expansion of the heterogeneous Fenton-like catalyst family and its application in the field of water treatment.


Asunto(s)
Colorantes , Contaminantes Químicos del Agua , Antibacterianos , Peróxido de Hidrógeno , Hierro
10.
BMC Infect Dis ; 19(1): 390, 2019 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-31068141

RESUMEN

BACKGROUND: Persistent infection with high-risk human papillomavirus (HR-HPV) is a major cause of cervical intraepithelial neoplasia and invasive cervical cancer. We investigated the prevalence of HR-HPV infection and distribution of viral genotypes among women in this area. METHODS: Women in Sichuan older than 20 years were screened for cervical cancer between January 2015 and December 2016 using liquid-based cytology testing and a flow cytometry-fluorescence hybridization test for HPV-DNA. Frequency tables were evaluated using the chi-squared test (χ2). RESULTS: Of the 17,319 women aged 20-85 years who participated in the study, Overall prevalence of HR-HPV infection was 12.6% (2178/17,319). The most prevalent viral type was HPV-52, which was present in 2.5% of individuals, followed by HPV-53 (1.6%), HPV-58 (1.5%), HPV-16 (1.1%), HPV-56 (0.9%), HPV-39 (0.8%). In HSIL, the five most common HR-HPV types were HPV52, 16, 58, 33 and 56. HPV16/18 in HSIL only makes up 25.9% of HSIL, whereas HPV31/33/45/52/58 make up 56.8%. Overall HR-HPV prevalence among women older than 65 years was 15.2%, significantly higher than the prevalence in other age groups (P < 0.05). Infection with dual or multiple HR-HPV types was associated with greater risk of abnormal cytology. CONCLUSION: Overall HR-HPV prevalence in Sichuan is as high as in large cities in China. The HR-HPV types 52, 16, 58, 33 and 56 predominated in this sample of HSIL women primarily from the banking and public sector in Sichuan. High prevalence among women older than 65 years needed pay attention to.


Asunto(s)
Papillomaviridae/genética , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/virología , Adulto , Anciano , Anciano de 80 o más Años , China/epidemiología , Estudios Transversales , Citodiagnóstico/métodos , Femenino , Genotipo , Humanos , Persona de Mediana Edad , Papillomaviridae/patogenicidad , Prevalencia
11.
J Colloid Interface Sci ; 533: 588-597, 2019 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-30193145

RESUMEN

Consumption of water having excessive arsenic (As) contamination can cause adverse health effects on human beings. In this study, novel ultra-large zirconium oxide (ZrO2) nanosheets were successfully synthesized using graphene oxide (GO) templates and their adsorption-ability was studied for arsenite (As(III)). Owing to higher values of surface area, numbers of available hydroxyl groups and strong chemisorption binding affinity towards As(III), the synthesized novel ultra-large ZrO2 nanosheets showed high adsorption-ability for As(III) over a wide pH range. Experimental results demonstrated that the maximum adsorption-ability of the ZrO2 nanosheets for As(III) reached to 74.9 mg/g at pH 6. BET, zeta potential, effect of initial pH, FTIR and XPS have been used to analyze the As(III) adsorption process on the ZrO2 nanosheets. The experiments for effects of co-existing ions indicated that ZrO2 nanosheets possessed good anti-interference ability towards co-existing ions. Furthermore, the ZrO2 nanosheets demonstrated very fast and excellent treatment of simulated real As(III) polluted water, consequently the effluent concentration met the standard regulated by World Health Organization. This study suggested that the as-prepared ZrO2 nanosheets could be potentially applied in practical drinking water treatment.

12.
Nanoscale ; 11(3): 1047-1057, 2019 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-30569932

RESUMEN

The presence of antibiotics in aquatic environments has attracted global concern. The Fenton system is one of the most popular methods for eliminating antibiotics in aquatic environments, but the existing Fenton system is limited due to the potential for secondary pollution, and the narrow pH range (∼3-5). In this study, we report that the bottlenecks for high-strength tetracycline (TC) wastewater treatment under neutral conditions can be tackled well by a class of mixed-valence W/Mo containing oxides (WMoO-x) with tunable morphologies. Triethanolamine was selected as a structure-directing agent to control the morphologies of the catalysts going from ultrathin nanowires (UTNWs) to wire-tangled nanoballs (WTNBs). As a proof of concept, the most efficient catalyst in the batch samples, WMoO-1 ultrathin nanowires, was employed as a model material for TC degradation, in which the coordinatively unsaturated metal atoms with oxygen defects serve as the sites for TC chemisorption and electron transfer. As a result, 91.75% of TC was degraded in 60 min for the initial TC concentration of 400 µM. Furthermore, LC-MS analysis confirmed that the TC could be degraded to nontoxic by-products without benzene rings, and finally mineralized to CO2 and H2O. ICP-MS and cycle experiments showed the good stability and reusability of WMoO-1 UTNWs in the Fenton-like system. The findings of this work provide fresh insights into the design of nanoscale catalyst morphology and reaffirm the versatility of doping in tuning catalyst activity, extending the range of the optimal pH values to neutral conditions. This is significant for the expansion of the heterogeneous Fenton-like family and its application in the field of water treatment.

13.
J Environ Manage ; 226: 256-263, 2018 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-30121461

RESUMEN

Industrial waste, urban sewage and aquaculture have led to severely increased grades of environment pollutants such as dyes, pesticides and fertilizer. The use of technologies for purifying contaminated waters can be difficult and toxic due to the anti-photolysis, anti-oxidation and anti-bio-oxidation characteristics of organic pollutants, and there is therefore a significant need for new approaches. Here, we report methods of Fenton oxidation and EDTA-Fe(III) Fenton-like oxidation which can be used to degrade malachite green (MG: a dye and antibiotic-like substance) from contaminated water. Compared with the degradation rate (59.34%) of the Fe(III)/H2O2 Fenton process, the EDTA-Fe(III) Fenton-like oxidation got a better degradation rate (92.7%) at neutral pH conditions. By conducting a series of parallel controlled experiments (changing parameters such as the reactant concentration, temperature, and pH), we report the relationships between the degradation effect and different parameters, and we fitted their pseudo first order kinetic curves. Furthermore, we repeated to adjustment of the concentrations of MG in solutions to test the cycle performance and catalytic activities of EDTA-Fe(III)/H2O2 system and it showed good repeatability in the first five rounds and all of them keep the degradation efficiencies greater than 80%. By conducting comparative spin-trapping electron paramagnetic resonance (EPR) experiments, we showed indirectly that the OH contributes to the degradation of MG. Additionally, the results of the EPR experiments showed that EDTA contributes to the generation of OH in the EDTA-Fe(III)/H2O2 Fenton-like system. By conducting total organic carbon (TOC) analysis experiments, we found that EDTA was also oxidized to some extent during the degradation of MG. In all, the findings of this work widen the range of the optimal pH values up to neutral condition for degradation of MG by use of EDTA-Fe(III) Fenton-like system. And this system could be used as one approach for the degradation of organic pollutants at neutral conditions and provide some initial information regarding EDTA-Fe(III) Fenton-like oxidations. It's significant for the expansion of the homogenous Fenton-like family and its application in the field of water treatment.


Asunto(s)
Colorantes de Rosanilina/química , Contaminantes Químicos del Agua/química , Ácido Edético , Peróxido de Hidrógeno , Hierro , Oxidación-Reducción , Colorantes de Rosanilina/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación
14.
BMC Womens Health ; 18(1): 130, 2018 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-30053844

RESUMEN

BACKGROUND: Since most cervical cancer cases are caused by persistent high-risk human papillomavirus (HR-HPV) infection, knowledge of HPV among women is essential for the prevent of cervical cancer. This study was aimed to assess knowledge among women in western China about HPV and its association with cervical cancer, and to assess their acceptance of HPV vaccination. METHODS: A sample of healthy women undergoing routine physical examinations in the Health Management Center of West China Hospital, Sichuan University between January and December 2014 completed a questionnaire. RESULTS: A total of 1300 questionnaires were distributed, and 1109 were completed and analyzed. Only 28.85% of respondents (n = 320) had heard of HPV; among this subgroup, only half (53.44%) knew that it causes cervical cancer, only 26 (8.13%) correctly answered all questions about HPV. Multivariate analysis showed that respondents who had heard of HPV were more likely than other respondents to have a family history of any cancer, to undergo regular Pap tests and to have completed at least secondary education. Half of all respondents (51.22%) reported that they would be willing to be vaccinated against HPV. CONCLUSION: Although most women in western China lack basic knowledge about HPV, at least half are willing to take the HPV vaccine. Public health efforts to educate the public about HPV and its connection to cervical cancer should be strengthened and expanded.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/uso terapéutico , Neoplasias del Cuello Uterino/prevención & control , Salud de la Mujer , Adolescente , Adulto , China , Estudios Transversales , Femenino , Humanos , Salud Pública , Encuestas y Cuestionarios , Frotis Vaginal/estadística & datos numéricos , Adulto Joven
15.
RSC Adv ; 9(1): 397-407, 2018 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-35521596

RESUMEN

Copper (Cu2+), cadmium (Cd2+) and lead ions (Pb2+) are toxic to human beings and other organisms. In this study, a silica gel material modified with nitrilotriacetic acid (NTA-silica gel) was sensibly designed and prepared via a simple amidation procedure for the removal of Cu2+, Cd2+ and Pb2+ from water. The NTA-silica gels showed rapid removal performances for the three metal ions (Pb2+ (<2 min), Cu2+ and Cd2+ (<20 min)) with relatively high adsorption capacities (63.5, 53.14 and 76.22 mg g-1 for Cu2+, Cd2+ and Pb2+, respectively). At the same concentration of 20 mg L-1, the removal efficiencies of the three metals by the adsorbent ranged from 96% to 99%. The Freundlich and Langmuir models were utilized to fit the adsorption isotherms. The adsorption kinetics for the three metal ions was pseudo-second-order kinetics. The removal performance of the NTA-silica gels increased in a wide pH range (2-9) and maintained in the presence of competitive metal ions (Na+, Mg2+, Ca2+ and Al3+) with different concentrations. In addition, the NTA-silica gels were easily regenerated (washed with 1% HNO3) and reused for 5 cycles with high adsorption capacity. This study indicates that the NTA-silica gel is a reusable adsorbent for the rapid, convenient, and efficient removal of Cu2+, Cd2+, and Pb2+ from contaminated aquatic environments.

16.
J Colloid Interface Sci ; 511: 155-164, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-29017101

RESUMEN

Increasing exposure to arsenic (As) contaminated ground water has become a global health hazard to humanity. Suitable adsorbent for As removal from water, especially for As(III) than As(V), is an urgent but still a challenging task. In this study, waste orange peel (OP) was modified with magnetic nanoparticles followed by calcination as a novel adsorbent and investigated for instantaneous oxidation and adsorption of As(III) from aqueous solutions. The batch adsorption experimental results showed that calcined magnetic orange peel composites (CMOPC) exhibited superior As(III) adsorption capacity (10.3mg/g) as compared to similar cost effective adsorbents due to its high surface area, large pore size and greater numbers of active sites on its surface. The adsorption equilibrium data obeyed Langmuir model, and kinetic data was well described by the pseudo-second-order model. The adsorption mechanisms for As(III) might be involved ligand exchange of the hydroxyl in CMOPC to form Fe-O-As(III), and partial As(III) oxidation to As(V) followed by instantaneous adsorption on surface of CMOPC. The developed adsorbent has also demonstrated good anti-interference ability to co-existing ions, admirable regeneration ability and pronounced capacity in treating simulated real As(III) contaminated water. This study revealed that waste orange peel, after simple treatment could be used as a potential adsorbent for As(III) from aqueous solutions.


Asunto(s)
Arsenitos/química , Calcio/química , Citrus sinensis/química , Frutas/química , Nanopartículas/química , Adsorción , Oxidación-Reducción , Porosidad
17.
J Zhejiang Univ Sci B ; 18(11): 955-962, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29119733

RESUMEN

OBJECTIVE: Fentanyl-induced cough (FIC) is a common complication with a reported incidence from 18.0% to 74.4% during general anesthesia induction. FIC increases the intrathoracic pressure and risks of postoperative nausea and vomiting, yet available treatments are limited. This study was designed to investigate whether administering fentanyl via a slow intravenous fluid line can effectively alleviate FIC during induction of total intravenous general anesthesia. METHODS: A total number of 1200 patients, aged 18-64 years, were enrolled, all of whom were American Society of Anesthesiologists (ASA) grade I or II undergoing scheduled surgeries. All patients received total intravenous general anesthesia, which was induced sequentially by midazolam, fentanyl, propofol, and cisatracurium injection. Patients were randomly assigned to receive fentanyl 3.5 µg/kg via direct injection (control group) or via a slow intravenous fluid line. FIC incidence and the severity grades were analyzed with the Mann-Whitney test. Other adverse reactions, such as hypotension, hypertension, bradycardia, tachycardia, hypoxemia, vomiting, and aspiration, during induction were also observed. The online clinical registration number of this study was ChiCTR-IOR-16009025. RESULTS: Compared with the control group, the incidence of FIC was significantly lower in the slow intravenous fluid line group during induction (9.1%, 95% confidence interval (CI): 6.7%-11.4% vs. 55.9%, 95% CI: 51.8%-60.0%, P=0.000), as were the severity grades (P=0.000). There were no statistical differences between the two groups with regard to other adverse reactions (P>0.05). CONCLUSIONS: The administration of fentanyl via a slow intravenous fluid line can alleviate FIC and its severity during induction for total intravenous general anesthesia. This method is simple, safe, and reliable, and deserves clinical expansion.


Asunto(s)
Anestésicos Intravenosos/administración & dosificación , Tos/prevención & control , Fentanilo/administración & dosificación , Fentanilo/efectos adversos , Adolescente , Adulto , Anestesia General/métodos , Atracurio/administración & dosificación , Atracurio/análogos & derivados , Femenino , Humanos , Incidencia , Infusiones Intravenosas , Masculino , Midazolam/administración & dosificación , Persona de Mediana Edad , Seguridad del Paciente , Propofol/administración & dosificación , Reproducibilidad de los Resultados , Método Simple Ciego , Adulto Joven
18.
Chemosphere ; 174: 380-389, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28187384

RESUMEN

A biocompatible and uniquely defined hydroxyapatite (HAP) adsorption membrane with a sandwich structure was developed for the removal of organic micropollutants for the first time. Both the adsorption and membrane technique were used for the removal of organic micropollutants. The hydrophilicity and hydrophobicity of the HAP adsorbent and membrane were tunable by controlling the surface structure of HAP. The adsorption of organic micropollutants on the HAP adsorbent was studied in batch experiments. The adsorption process was fit with the Freundlich model, while the adsorption kinetics followed the pseudo-second-order model. The HAP membrane could remove organic micropollutants effectively by dynamic adsorption in both aqueous and ethanol solutions. The removal efficiencies of organic micropollutants depended on the solution composition, membrane thickness and hydrophilicity, flow rate, and the initial concentration of organic micropollutants. The adsorption capacities of the HAP membrane with a sandwich structure (membrane thickness was 0.3 mm) were 6700, 6510, 6310, 5960, 5490, 5230, 4980 and 4360 L m-2 for 1-naphthyl amine, 2-naphthol, bisphenol S, propranolol hydrochloride, metolachlor, ethinyl oestradiol, 2,4-dichlorophenol and bisphenol A, respectively, when the initial concentration was 3.0 mg L-1. The biocompatible HAP adsorption membrane can be easily regenerated by methanol and was thus demonstrated to be a novel concept for the removal of organic micropollutants from both aqueous and organic solutions.


Asunto(s)
Durapatita/química , Etanol/química , Interacciones Hidrofóbicas e Hidrofílicas , Membranas Artificiales , Compuestos Orgánicos/química , Compuestos Orgánicos/aislamiento & purificación , Agua/química , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Soluciones , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación
19.
J Colloid Interface Sci ; 494: 307-316, 2017 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-28161502

RESUMEN

A new adsorbent, Fe3O4 sulfonated magnetic nanoparticle (Fe3O4-SO3H MNP), was developed for heavy metal ions removal from water, which could be effectively separated from the solution owing to the superparamagnetic property. The nanoparticles can be used to remove heavy metal ions due to the additional active site, "sulfo-group", introduced by the AMPS branches grafted onto the iron oxide. The as-synthesized materials were characterized by SEM, TEM, FT-IR and BET. The FTIR, XPS and Zeta potential were used to describe the adsorption mechanism. The Fe3O4-SO3H MNPs showed rapid removal for Pb2+ and Cd2+ with maximum of adsorption capacity of 108. 93 and 80.9mg/g at 25°C, respectively. The adsorption isotherms for Pb2+ and Cd2+ fitted better with Langmuir than Freundlich models, indicated that the processes of the removal of Pb2+ and Cd2+ could follow a kind of similar adsorption manner. The adsorption kinetic was consistent with pseudo-second-order model. Furthermore, the reuse experiments results showed the adsorbent might have potential in treating heavy metal ions pollution in water.

20.
J Colloid Interface Sci ; 490: 97-107, 2017 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-27870965

RESUMEN

A biocompatible and novelly-defined adsorption membrane for rapid removal of fluoride was prepared. Both adsorption and membrane techniques were used in this research. Al(OH)3 nanoparticles modified hydroxyapatite (Al-HAP) nanowires were developed and made into Al-HAP membrane. The adsorption data of Al-HAP adsorbent could be well described by Freundlich isotherm model while the adsorption kinetic followed pseudo-second-order model. The maximum of adsorption capacity was 93.84mg/g when the fluoride concentration was 200mg/L. The adsorption mechanism was anion exchanges and electrostatic interactions. The contribution rates of HAP nanowires and Al(OH)3 nanoparticles in fluoride removal were 36.70% and 63.30%, respectively. The fixed-bed column test demonstrate that the Al-HAP was biocompatible and in a good stability during the process of water treatment. The fluoride removal abilities of Al-HAP membrane with 0.3mm thickness could reach 1568L/m2 when fluoride concentrations were 5mg/L. This study indicated that the Al-HAP membrane could be developed into a very viable technology for highly effective removal of fluoride from drinking water.


Asunto(s)
Hidróxido de Aluminio/química , Agua Potable/análisis , Durapatita/química , Fluoruros/aislamiento & purificación , Membranas Artificiales , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Adsorción , Nanopartículas/química , Nanopartículas/ultraestructura , Nanocables/química , Nanocables/ultraestructura
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