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1.
J Environ Manage ; 351: 119730, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38086123

RESUMO

In this study, the behavior of heavy metal transformation during the co-thermal treatment of hazardous waste incineration fly ash (HWIFA) and Fe-containing hazardous waste (including hazardous waste incineration bottom slag (HWIBS) and electroplating sludge (ES)) was investigated. The findings demonstrated that such a treatment effectively reduced the static leaching toxicity of Cr and Pb. Moreover, when the treatment temperature exceeded 1000 °C, the co-thermal treated sample exhibited low concentrations of dynamically leached Cr, Pb, and Zn, indicating that these heavy metals were successful detoxified. Thermodynamic analyses and phase transformation results suggested that the formation of spinel and the gradual disappearance of chromium dioxide in the presence of Fe-containing hazardous wastes contributed to the solidification of chromium. Additionally, the efficient detoxification of Pb and Zn was attributed to their volatilization and entry into the liquid phase during the co-thermal treatment process. Therefore, this study sets an excellent example of the co-thermal treatment of hazardous wastes and the control of heavy metal pollution during the treatment process.


Assuntos
Metais Pesados , Eliminação de Resíduos , Cinza de Carvão , Eliminação de Resíduos/métodos , Esgotos/análise , Resíduos Perigosos/análise , Galvanoplastia , Chumbo , Incineração/métodos , Metais Pesados/análise , Resíduos Sólidos/análise , Carbono , Material Particulado/análise
2.
J Environ Manage ; 338: 117776, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-36965423

RESUMO

Based on the CaO-SiO2-Al2O3 system, the feasibility of co-vitrification of hazardous waste incineration fly ash (FA) and hazardous waste sludge (HWS) was verified. In the CaO-SiO2-Al2O3 ternary system diagram, the melting point of the system gradually decreases with an appropriate increase in SiO2 content when the CaO/Al2O3 ratio is determined to be approximately 1. The TG-DSC results revealed that the liquid phase generation temperature in the FA and HWS mixture system was significantly lower than those of FA and HWS individually owing to the different CaO, SiO2, and Al2O3 contents; this is consistent with the results of the theoretical melting characteristics analysis, which show that the melting characteristic temperatures can be reduced by controlling the CaO-SiO2-Al2O3 ratio in the system. The co-vitrification experimental results confirmed that a vitreous content above 92%, a loss ratio on acid dissolution less than 1.74%, and leaching toxicity of heavy metals lower than 0.15 mg/L could be obtained by adjusting the CaO, SiO2, and Al2O3 contents in the FA and HWS system to 20 wt%-32.5 wt%, 35 wt%-61 wt% and 14 wt%-32.5 wt%, respectively, and under a melting temperature of 1350 °C.


Assuntos
Metais Pesados , Eliminação de Resíduos , Cinza de Carvão , Incineração , Dióxido de Silício , Esgotos , Vitrificação , Metais Pesados/análise , Resíduos Sólidos/análise , Eliminação de Resíduos/métodos , Carbono , Resíduos Perigosos , Material Particulado/análise
3.
Artigo em Inglês | MEDLINE | ID: mdl-28003850

RESUMO

The study attempted to explore that the synergistic effect of acupoints combination is not a simple superposition of single acupoint's effect by comparing and analyzing the changes of blood pressure (BP), SF-36, and brain regions after acupuncture treatment. 47 patients were randomly divided into LR3+KI3 group, LR3 group, and KI3 group. Subjects received Rs-fMRI scan, BP measurement, and SF-36 questionnaires before and after treatment and short-term acupuncture treatment. After treatment, there were no significant differences in BP and SF-36 among 3 groups, compared to the case before treatment, SBP of 3 groups decreased, and DBP significantly decreased while vitality and mental health significantly increased in LR3+KI3 group. Both number and scopes of changes of brain regions in LR3+KI3 group were the largest, which mainly included BAs 3, 4, 8, 19, 21, 24, 32, 44, and 45. In conclusion, acupuncture at LR3+KI3 may auxiliarily reduce BP and improve the vitality and mental health of patients, and the changes of brain regions were related to somatesthesia, movement, vision, audition, emotion and mood, language, memory, etc. BAs 4, 9, 10, 24, 31, 32, and 46 may be the targeting brain areas of acupuncture in assisting hypotension. It is suggested that acupoints combination of LR3+KI3 maybe generates a synergistic effect, and it is not simple sum of single acupoint effect.

4.
Biodegradation ; 27(1): 37-46, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26749222

RESUMO

This study evaluated substrate interactions during the aerobic biodegradation of 1, 4-dioxane and BTEX mixtures by a pure culture, Acinetobacter baumannii DD1, which is capable of utilizing 1, 4-dioxane for growth. A. baumannii DD1 could utilize BTEX as a sole carbon source, but could not utilize m-xylene and p-xylene. In binary mixtures, there was a lag of about 14 h before the degradation of BTE, and 1, 4-dioxane only started to be utilized when BTE was completely degraded by 1, 4-dioxane-grown DD1. Furthermore, the biodegradation rate of 1, 4-dioxane decreased from 73.33 to 40.74 mg/(h g dry weight) after the biodegradation of benzene. 1, 4-dioxane could not be degraded after the biodegradation of o-xylene in 80 h. DD1 could also not degrade m-xylene and p-xylene coexisting with 1, 4-dioxane. The ability of DD1 to degrade BTEX occurred in the following order: benzene > ethylbenzene > toluene > o-xylene > m-xylene = p-xylene. The biodegradation of 1, 4-dioxane was not activated in the mixture with o-xylene, primarily because of the accumulation of the specific toxic intermediate, 2, 3-dimethylphenol. The lag in BTE degradation was presumably because of the induction of enzymes necessary for BTE degradation. Additionally, SDS-PAGE analysis demonstrated that there were different proteins during the degradation of benzene and 1, 4-dioxane.


Assuntos
Acinetobacter baumannii/metabolismo , Derivados de Benzeno/metabolismo , Biodegradação Ambiental , Dioxanos/metabolismo , Acinetobacter baumannii/enzimologia , Benzeno/metabolismo , Dioxigenases/metabolismo , Oxigenases/metabolismo , Xilenos/metabolismo
5.
Waste Manag ; 38: 381-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25661690

RESUMO

Changes in water states during the composting of kitchen waste were determined. Three experiments, R(55), R(60), and R(65), with different initial moisture contents, 55%, 60%, and 65%, respectively, were performed. Three water states, entrapped water (EW), capillary water (CW), and multiple-molecular-layer water (MMLW), were monitored during the experiments. Changes only occurred with the EW and CW during the composting process. The percentage of EW increased, and the percentage of CW decreased as the composting process progressed. The R(60) experiment performed better than the other experiments according to changes in the temperature and carbon-to-nitrogen ratio (C/N). The percentage of EW correlated well (P<0.05) with the dissolved organic carbon content (DOC), electrical conductivity (EC), pH, and C/N, and was affected by the hemicellulose and cellulose contents.


Assuntos
Resíduos de Alimentos , Reciclagem , Resíduos Sólidos/análise , Água/análise , Eliminação de Resíduos
6.
Acupunct Med ; 33(1): 30-5, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25476448

RESUMO

OBJECTIVE: To explore the effect of acupuncture at HT7 on heart rate variability (HRV) in healthy volunteers. METHODS: 120 subjects were divided into four groups using a random number table. The following groups of acupuncture interventions were used: HT7 verum acupuncture; HT7 non-penetrating sham acupuncture; acupuncture at a sham point; and no acupuncture. HRV was recorded 10 min before, during and after each stimulation using an Actiheart ECG recorder. RESULTS: The HT7 verum acupuncture group had higher very-low frequency, low frequency and high frequency components of HRV compared with the control groups during but not after acupuncture. The HT7 verum acupuncture group also had higher SD of normal intervals compared with the sham needling and no acupuncture control groups. CONCLUSIONS: Our preliminary study suggests, subject to limitations, that acupuncture at HT7 could affect cardiac autonomic neural regulation in healthy subjects, manifest as increased HRV, most likely via the parasympathetic system. TRIAL REGISTRATION NUMBER: ChiCTR-TRC-08000302.


Assuntos
Pontos de Acupuntura , Terapia por Acupuntura , Sistema Nervoso Autônomo , Frequência Cardíaca , Coração/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
7.
Neural Regen Res ; 8(9): 857-62, 2013 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-25206734

RESUMO

A total of 30 students scoring between 12 and 20 on the Test Anxiety Scale who had been exhibiting an anxious state > 24 hours, and 30 normal control students were recruited. Indices of heart rate variability were recorded using an Actiheart electrocardiogram recorder at 10 minutes before auricular pressing, in the first half of stimulation and in the second half of stimulation. The results revealed that the standard deviation of all normal to normal intervals and the root mean square of standard deviation of normal to normal intervals were significantly increased after stimulation. The heart rate variability triangular index, very-low-frequency power, low-frequency power, and the ratio of low-frequency to high-frequency power were increased to different degrees after stimulation. Compared with normal controls, the root mean square of standard deviation of normal to normal intervals was significantly increased in anxious students following auricular pressing. These results indicated that auricular pressing can elevate heart rate variability, especially the root mean square of standard deviation of normal to normal intervals in students with pre-exam anxiety.

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