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1.
Mikrochim Acta ; 191(6): 337, 2024 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-38777890

RESUMO

A ratiometric fluorescence method comprising carbon dots (CDs) and rhodamine 6G (Rh-6G) encapsulated in the microcubes of metal-organic framework (MOF-5) is introduced for the sensitive detection of curcumin (Cur) in condiments. CDs@MOF-5@Rh-6G, synthesized by the adsorption of Rh-6G on MOF-5 embedded with CDs, showed two distinct emission peaks at 435 and 560 nm under excitation at 335 nm, and could be used for Cur detection by ratiometric fluorescence. In the presence of Cur, the fluorescence of the CDs at 435 nm (F435) was quenched by Cur owing to internal filtering and dynamic quenching effects, whereas the emission of Rh-6G at 560 nm (F560) remained unchanged (335 nm is the excitation wavelength, 435 and 560 nm are the emission wavelengths, in which F435/F560 values are used as the output results). Under optimal conditions, a linear relationship was observed between the Cur concentration (in the range 0.1-5 µmol/L) and F435/F560 value for CDs@MOF-5@Rh-6G, with a detection limit of 15 nmol/L. Notably, the proposed method could accurately detect Cur in mustard, curry, and red pepper powders. Therefore, this study could improve the quality control of food and facilitate the development of sensitive ratiometric fluorescence probes.


Assuntos
Carbono , Curcumina , Corantes Fluorescentes , Limite de Detecção , Estruturas Metalorgânicas , Pontos Quânticos , Rodaminas , Espectrometria de Fluorescência , Curcumina/química , Rodaminas/química , Carbono/química , Estruturas Metalorgânicas/química , Pontos Quânticos/química , Espectrometria de Fluorescência/métodos , Corantes Fluorescentes/química
2.
J Environ Manage ; 279: 111772, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33310238

RESUMO

This study investigated responses of anaerobic digestion (AD) of food waste (FW) with different inocula to varying organic loads and to pH control under high load in terms of process performance and microbial characteristics. Without pH control, digester inoculated by thickened sludge obtained high methane yield of 547.8 ± 27.8 mL/g VS under organic load of 7.5 g VS/L but was inhibited by volatile fatty acids (VFAs) under higher loads (15 and 30 g VS/L). However, digesters inoculated by anaerobic sludge obtained high methane yields of 575.9 ± 34.2, 569.3 ± 24.8 and 531.9 ± 26.2 mL/g VS under organic loads of 7.5, 15 and 30 g VS/L and VFAs inhibition only appeared under extremely high load of 45 g VS/L. Digesters under VFA inhibition with high load were significantly enhanced by controlling single ecological factor pH at 6.5, 7.0 and 7.5, as indicated by shorter lag phases, higher peak values of methane production rate, greater methane yields and fast VFAs degradation. Maximum methane recovery was obtained with pH control at 7.5 under high load. VFA inhibition was accompanied by the degeneration of ecological functions of Syntrophomonadaceae and unidentified Bacteroidales and the dominant growth of unidentified Clostridiales. Under high load and pH control, high stability was strongly associated with obvious growth of Methanosarcina, which enriched methanogenic pathways thus improved system robustness and tolerance to VFAs. Moreover, pH control stimulated the growth of syntrophic Bacteria Syntrophomonadaceae while maintaining the high activity of hydrogenotrophic methanogens therefore sustained efficient syntrophic communities of Bacteria and methanogens and avoided over accumulation of VFAs. pH control promoted adaptive selection of methanogens, leading to obvious decline of archaeal community diversity. This study provided practical guidance on digester configurations of high-load AD of FW and expanded the understanding of responses to coupling effects of inoculum origins, organic loads and pH control under high load concerning process performance and microbial community dynamics.


Assuntos
Reatores Biológicos , Eliminação de Resíduos , Anaerobiose , Alimentos , Concentração de Íons de Hidrogênio , Metano
3.
Distrib Parallel Databases ; 37(3): 411-439, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31889741

RESUMO

We consider data analytics workloads on distributed architectures, in particular clusters of commodity machines. To find a job partitioning that minimizes running time, a cost model, which we more accurately refer to as makespan model, is needed. In attempting to find the simplest possible, but sufficiently accurate, such model, we explore piecewise linear functions of input, output, and computational complexity. They are abstract in the sense that they capture fundamental algorithm properties, but do not require explicit modeling of system and implementation details such as the number of disk accesses. We show how the simplified functional structure can be exploited to reduce optimization cost. In the general case, we identify a lower bound that can be used for search-space pruning. For applications with homogeneous tasks, we further demonstrate how to directly integrate the model into the makespan optimization process, reducing search-space dimensionality and thus complexity by orders of magnitude. Experimental results provide evidence of good prediction quality and successful makespan optimization across a variety of operators and cluster architectures.

4.
J Environ Biol ; 37(2): 305-12, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27097452

RESUMO

Extracellular polymer substance (EPS) is an important substance in sludge dewatering process and can be divided into slime, loosely bound EPS(LB-EPS) and tightly bound EPS(TB-EPS). The major components in different EPS layers in mechanical dewatered sludge (sample D) and sludge from thickening tank (sample U) were analyzed in the study. Results showed that, for all sludge samples, protein content in slime was much higher than that in LB-EPS and TB-EPS. In addition, from the results of total EPS content in four sludge samples (U: 98.68 mg gvss⁻¹, US (sample U+SDS): 135.27 mg gvss⁻¹, D:138.16 mg gvss⁻¹, DS:211.21 mg gvss⁻¹), it was found that sodium dodecyl sulfate (SDS) extracted more EPS content from sludge, which proved that SDS might cause substantial release of EPS, especially PN from sludge. Increase PS content in LB-EPS, and TB-EPS as addition of SDS, implied sensibility of cells in sludge to SDS. Differential Scanning Calorimetry found that bound water proportion in four different sludge samples ranged as follows: as D>DS>US>U. Results from other analytical techniques,such as FTIR and NMR, were also given the supported proof for the distribution changes of EPS and bound water.


Assuntos
Polímeros/química , Esgotos/química , DNA/química , Proteínas , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Eliminação de Resíduos Líquidos
5.
Waste Manag Res ; 32(8): 726-32, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25092381

RESUMO

This study discussed the effects of different concentrations (0.625, 1.875 and 3.125 mM) of copper (Cu) in the form of CuSO4 on biomethane production and on the dynamics of microbial communities during the mesophilic anaerobic digestion (AD) of cow manure. The effects on biomethane production were found to depend on CuSO4 concentrations. After 50 days of AD, treatment A3 (3.125 mM) had lower cumulative biomethane production than the no-Cu control. The maximum value of cumulative biomethane production was detected under treatment A2 (1.875 mM). These results suggested that the stimulation or inhibition to biomethane production might be related to the concentration and chemical forms of Cu. Moreover, polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) was used to discuss the dynamics of microbial communities. Results revealed that different concentrations of CuSO4 had effects on the richness and diversity of bacterial and archaeal communities. The predominance of Bacteroidetes bacterium (GU339485.1) was verified through the sequencing of the dominant DGGE bands. Furthermore, Bacteroidetes bacterium could be detected during the whole AD process and is adaptable to a certain concentration range of CuSO4.


Assuntos
Archaea/metabolismo , Bactérias/metabolismo , Biocombustíveis/análise , Sulfato de Cobre/metabolismo , Metano/biossíntese , Anaerobiose/efeitos dos fármacos , Animais , Archaea/efeitos dos fármacos , Archaea/genética , Bactérias/efeitos dos fármacos , Bactérias/genética , Reatores Biológicos/microbiologia , Bovinos , Eletroforese em Gel de Gradiente Desnaturante , Relação Dose-Resposta a Droga , Fermentação , Esterco/microbiologia , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , RNA Arqueal/genética , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
6.
J Psychiatr Res ; 169: 347-354, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38091723

RESUMO

Leptin and insulin-like growth factor-1 (IGF-1) may play a role in clinical identification of post-stroke depression (PSD). Here, eight databases (including CNKI, Wanfang, SinoMed, VIP, PubMed, the Cochrane Library, Embase, and the Web of Science) were employed to search for studies on serum leptin and insulin-like growth factor-1 expression levels in patients with PSD. In total, 13 articles were included, of which 6 studies investigated the expression level of serum leptin in patients with PSD, 7 studies explored the serum IGF-1 in PSD patients. Then, the RevMan 5.4 software was used for meta-analysis. The results showed that serum leptin levels were significantly higher in PSD patients than in patients without PSD (SMD = 1.54, 95% CI: 0.84, 2.23; P = 0.006). The result of subgroup analysis showed that the serum leptin levels in PSD patients were significantly higher than those without PSD in acute phase (SMD = 1.38, 95% CI: 0.04, 2.71; P = 0.04), subacute phase (SMD = 2.31, 95% CI: 0.88, 3.73; P = 0.001), and chronic phase (SMD = 1.02, 95% CI: 0.43, 1.60; P = 0.0007); There was no significant difference in serum IGF-1 level between PSD patients and patients without PSD (SMD = 0.49, 95% CI: -0.55, 1.52; P = 0.36). Moreover, the subgroup analysis also showed that there was no statistical difference in acute stage (SMD = 0.36, 95% CI: 0.89, 1.60; P = 0.57). Our study provides evidence to prove that serum leptin level has potential clinical application value as biomarkers for identifying PSD.


Assuntos
Depressão , Acidente Vascular Cerebral , Humanos , Biomarcadores , Depressão/diagnóstico , Depressão/etiologia , Fator de Crescimento Insulin-Like I/análise , Peptídeos Semelhantes à Insulina , Leptina , Acidente Vascular Cerebral/complicações
7.
Artigo em Inglês | MEDLINE | ID: mdl-38844127

RESUMO

Interleukins may play a role in supporting the diagnosis of post-stroke depression (PSD). Here, eight databases were employed to search for studies on circulating interleukins concentrations in patients with PSD. A total of 45 studies exploring circulating interleukins in PSD and stroke patients without depression (NPSD) were included in the retrieval database, including IL-1(5), IL-1ß (10), IL-2(6), IL-6(35), IL-10(7), IL-17(5), IL-18(6). Then, the RevMan 5.4 software was used for meta-analysis. The results of the meta-analysis showed that the PSD patients have higher concentrations of IL-1, IL-4, IL-6, and lower concentrations of IL-10 than NPSD patients. Additionally, the circulating IL-1, IL-6, and IL-18 concentrations in PSD patients were significantly higher than those in NPSD patients in the acute phase; the circulating IL-6 and IL-17 concentrations in PSD patients were significantly higher than those in NPSD patients at discharge; the PSD patients have lower concentrations sin IL-2 but higher concentrations in IL-6 and IL-17 than NPSD patients at the 3rd and 6th month. Our research provides evidence that circulating interleukins may have clinical utility as a biomarker for identifying PSD.


Assuntos
Interleucinas , Acidente Vascular Cerebral , Humanos , Interleucinas/sangue , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/psicologia , Depressão/sangue , Depressão/etiologia , Biomarcadores/sangue
8.
ACS Omega ; 9(6): 6912-6923, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38371850

RESUMO

To investigate the feasibility and reaction mechanism of combusting sewage sludge and brown coal in a mixture. Thermal behavior evaluation of combustion characteristics, interactions, and kinetic analysis of sludge-lignite mixture combustion by thermogravimetry (TG). The results showed that the combustion performance of the mixed samples was all in between that of the lignite and sludge samples. The combined combustion index gradually decreased with the increase in sludge mixing. The addition of sludge favors the ignition of the mixture but is not conducive to overall stable combustion. The synergies between the sludges, as assessed by the mass loss curves, are reflected in the ash removal and coke oxidation stages. When the mixture of sludge and lignite is burned at a ratio of 10 wt %, the calorific value can still reach 20.3 MJ/kg, which is only about 4.2% lower than that of burning lignite alone. Application of the kinetic models of FWO, Starink, KAS, and Friedman, in turn, determined a minimum average activation energy of only 132.50 kJ/mol. In addition, the reaction was judged to be a simple complexation reaction by analyzing the thermodynamic parameters (ΔG, ΔS, ΔH, and A), with the combustion process approaching thermodynamic equilibrium and forming stable products. The nucleation model A4.2 can be used as the best reaction mechanism model for sludge-lignite mixed combustion.

9.
Sci Total Environ ; 926: 171920, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38527550

RESUMO

Solar energy, as a clean energy source, is becoming increasingly important in the global energy mix. However, particle deposition on the surface of photovoltaic (PV) panels can significantly reduce their power generation efficiency. In this study, the collision-deposition behaviour between silica particles and the surface of PV modules is investigated. The impact process of 13 µm silica particles on the glass surface was recorded by using a high-speed digital camera at various incident velocities and angles. A particle dynamics model was developed to predict the critical capture velocity of particles at different incident angles. It was observed that the critical capture velocity of the particles decreases as the angle of incidence increases. Subsequently, a correlation equation was established between the incident angle and the critical capture velocity, serving as the deposition criterion. Computational Fluid Dynamics (CFD) numerical simulation was employed to simulate particle deposition on PV surfaces under different wind speeds and installation tilting angles. The simulation results demonstrate that the mass of 13 µm silica particles deposited on the surface of PV panels decreases with increasing wind speed. Moreover, under identical inlet wind speeds, the particle deposition mass exhibits an initial decrease followed by a subsequent increase as the installation tilt angle of the PV panel increases. The distribution pattern of particle deposition on PV panel surfaces is diverse; however, predominantly concentrated at the mid-bottom region.

10.
Neuropeptides ; 104: 102412, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38330680

RESUMO

Neuropeptide Y (NPY), an extensively distributed neurotransmitter within the central nervous system (CNS), was initially detected and isolated from the brain of a pig in 1982. By binding to its G protein-coupled receptors, NPY regulates immune responses and contributes to the pathogenesis of numerous inflammatory diseases. The hippocampus contained the maximum concentration in the CNS, with the cerebral cortex, hypothalamus, thalamus, brainstem, and cerebellum following suit. This arrangement suggests that the substance has a specific function within the CNS. More and more studies have shown that NPY is involved in the physiological and pathological mechanism of stroke, and its serum concentration can be one of the specific biomarkers of stroke and related complications because of its high activity, broad and complex effects. By summarizing relevant literature, this article aims to gain a thorough understanding of the potential clinical applications of NPY in the treatment of stroke, identification of stroke and its related complications, and assessment of prognosis.


Assuntos
Neuropeptídeo Y , Receptores de Neuropeptídeo Y , Acidente Vascular Cerebral , Animais , Neuropeptídeo Y/metabolismo , Neuropeptídeo Y/uso terapêutico , Prognóstico , Receptores de Neuropeptídeo Y/metabolismo , Transdução de Sinais , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Suínos , Humanos
11.
Int J Biol Macromol ; 279(Pt 2): 135185, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39216581

RESUMO

The rate limiting stage is char reactivity during gasification that can be influenced by its physicochemical structural characteristics. In this study, the effects of feedstock share, rice straw (RS) and polyethylene (PE), on the physicochemical properties and gasification reactivity of chars were investigated and their relationships were discussed. The char gasification reactivity was investigated via isothermal experiments using a thermal analyzer. The results indicated that the PE addition improved the specific surface area (SSA) and pore volume (Vp) of the char obtained from co-pyrolysis RS with PE. The SSA of the char increased by 1.31 times when the PE content was 60 wt%, compared with that of RS char. The order degree and gasification reactivity of the co-pyrolysis char samples increased with increasing PE content beyond 40 wt%. The char reactivity in the early stage of co-gasification was primarily determined by the order degree of carbonaceous and pore structure. The char reactivity in the later stage was influenced by these two factors and the silicon dioxide content could inhibit the char co-gasification reactivity.

12.
Waste Manag Res ; 31(10): 1012-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23831774

RESUMO

Chlorine, sulfur and phosphorus were selected as element donators to investigate their effect on the volatilization behavior of heavy metals in sludge sewage incineration. Principal component analysis indicated that the promotive effect on the volatilization of heavy metals was followed by chlorine, sulfur and phosphorus. This result was proved to be correct by total release of heavy metals in sewage sludge incineration using different element donators. The release of heavy metals was very chlorine dependent, especially cadmium (Cd), lead (Pb) and nickel (Ni). When chlorine content was in the range of 0.1-0.5wt%, the increase of the volatilization rate was 44.9% for Cd, 6.8% for Pb and 4.6% for Ni, respectively. Although sulfur contributed to the promotion of the volatilization of heavy metals, excess oxygen impaired the promotive effect of sulfur on the release of heavy metals from the condensed phase. For phosphorus, solidifying heavy metals was dominant. Energy analysis showed that metal chlorides and sulfides were prone to volatilize or to be decomposed at elevated temperature compared with sulfates and phosphates owing to low binding energy in absolute value (VLFA). It was the difference of binding energy that led to the different volatilization behavior of metal compounds in a high temperature, oxygen-enriched atmosphere.


Assuntos
Poluentes Atmosféricos/química , Cloro/química , Recuperação e Remediação Ambiental/métodos , Metais Pesados/química , Fósforo/química , Esgotos/química , Enxofre/química , Poluentes Atmosféricos/análise , Incineração , Metais Pesados/análise , Análise de Componente Principal , Eliminação de Resíduos , Espectrofotometria Atômica
13.
ACS Omega ; 8(30): 27612-27620, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37546616

RESUMO

Developing non-carbon-based adsorbents is essential for removing heavy metals from post-incineration flue gas. In this study, a new high-temperature-resistant adsorbent-activated boron nitride (BN) was prepared using precursors combined with a high-temperature activation method. The adsorption characteristics of BN for Zn, Cu, and Cd in simulated flue gas and sludge incineration flue gas were investigated using gas-phase heavy metal adsorption experiments. The results showed that BN prepared at 1350 °C for 4 h had defect structures, abundant pores, functional groups, and a high specific surface area of 658 m2/g. The adsorption capacity of BN in simulated flue gases decreases with increasing adsorption temperature, whereas it is always higher than that of activated carbon (AC). The total adsorption capacities for Zn, Cu, and Cd were the highest at 50 °C with 48.3 mg/g. BN had strong adsorption selectivity for Zn, with a maximum adsorption capacity of 54.45 mg/g, and its adsorption process occurred mainly on the surface. Cu and Cd inhibited Zn adsorption, leading to a decrease in the Zn adsorption capacity. In sludge incineration flue gas, BN can quickly reach adsorption equilibrium. The BN had a synergistic disposal capacity for heavy metals and fine particulate matter. The maximum adsorption capacity was reduced compared to the simulated flue gas adsorption capacity, which was 5.1 mg/g. However, BN still exhibited a strong adsorption selectivity for Zn, and its adsorption capacity was always greater than that of AC. The rich functional groups and high specific surface area enable BN to physically and chemically double-adsorb heavy metals.

14.
Heliyon ; 9(9): e20318, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809520

RESUMO

In order to solve the problem that the accuracy of approximate position and approximate time information is limited by the traditional auxiliary positioning algorithm, this paper analyzes the problem that the calculation amount may increase and fail when these auxiliary information exceeds the precision requirement range and puts forward a positioning algorithm based on one-way fuzzy time assistance that is suitable for the positioning solution of GNSS satellite navigation receivers under the condition of fuzzy time information, such as the rotation condition. Methods using the reference information in the ephemeris information, the relatively accurate approximate time information can be reasonably searched and verified so as to achieve the effect of obtaining the positioning result with less calculation. The experimental results show that this method can accurately calculate the exact position even if there is an error in the approximate position information under the condition of one-way time assistance, which not only solves the problem that it cannot be positioned under the conditions of rotation but also does not increase the additional calculation amount and has practical engineering value.

15.
Artigo em Inglês | MEDLINE | ID: mdl-36767936

RESUMO

Beach waste is an important pollutant in the Bohai Sea and coastal cities around the Bohai Sea and has raised many social and environmental concerns in China. The semi-closed characteristics of the Bohai Sea, the well-developed tourism, the special industrial structure and residents' living habits endow the beach waste around Bohai sea with a unique character that should be explored. This study investigated changes in the sources and composition of beach waste in coastal cities around the Bohai Sea of China during the tourist peak and off-peak seasons. Beach waste from twenty beaches in thirteen coastal cities around the Bohai Sea was sampled and analyzed in March and August 2021, respectively. The results showed that beach waste around the Bohai Sea was characterized by large quantities and small weights and was greatly affected by human coastal activities. The sources and composition of beach waste from different coasts and different seasons varied, whereas the overall trend was consistent. In terms of composition, beach waste in both the tourist peak season and off-peak season was mainly composed of plastics, fabrics and paper, which accounted for more than 70% of the total in weight. Meanwhile, the proportion of plastics in the total quantity of beach waste was greatest (maximum of up to 71%) and exhibited seasonal fluctuations, trending higher in the tourist peak season than in the off-peak season. In contrast, trends in the proportion of paper and fabrics in the total quantity and total weight of beach waste were relatively stable in different seasons. In terms of sources, beach waste mainly derived from human coastal activities, the proportion of which in the total quantity of beach waste in the tourist peak season reached 70.55% and was 11% higher than that in the tourist off-peak season. Shipping/fishing activities were the second largest source of beach waste, and their proportion in the total quantity of beach waste in the tourist peak season was 5% lower than that in the tourist off-peak season, as the tourist peak season around the Bohai Sea coincides exactly with the fishing moratorium. The quantity of smoking-related waste only accounted for 9.35% and 7.73% of beach waste in the tourist peak and off-peak seasons, respectively. The special semi-enclosed structure of the Bohai gulf, surrounded by land on three sides, aggravated the accumulation of beach waste on the coast. Source reduction and classified recovery, collaborative management of marine waste and beach waste, and joint prevention and control mechanisms of three provinces (Liaoning, Hebei and Shandong) and one municipality (Tianjin) were suggested for comprehensive management of beach waste in coastal cities around the Bohai Sea of China. This study provided valuable information for beach waste management in coastal cities around the Bohai Sea of China.


Assuntos
Monitoramento Ambiental , Plásticos , Humanos , Cidades , Estações do Ano , Monitoramento Ambiental/métodos , China
16.
Org Lett ; 25(14): 2543-2547, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37018539

RESUMO

We report an efficient one-pot, two-step procedure for the modular synthesis of α-difunctionalized alkynes and trisubstituted allenes by sequential cross-coupling of benzal gem-diacetates with organozinc or -copper reagents in the absence of external transition metals. The intermediacy of propargylic acetates enables the divergent and selective synthesis of these valuable products. This method features its readily accessible substrates, relatively mild conditions, wide scope, and scalability in practical synthesis.

17.
Water Res ; 226: 119278, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36323207

RESUMO

Hydrothermal liquefaction (HTL) of sewage sludge is facing the challenges of low biocrude yield, a large number of intractable aqueous phase and heavy metals pollution. In this study, the aqueous phase produced by HTL was recycled as solvent with an aim to improve the biocrude yield and mitigate potential pollution. Results showed that the recycling of aqueous phase increased the biocrude yield from 17.9 to 30.5% and the energy recovery ratio from 40.3 to 61.7%. The recycling could increase the contents of Zn, Cu, Pb and Cr in solid residues by 2.7-3.0 times. It is worth emphasizing that the recycling reduced the COD of aqueous phase by 24.9%. However, the enhanced protein hydrolysis process reduced the calorific value of biocrude from 36.4 to 28.5 MJ/kg, and promoted the migration of the nitrogen to the aqueous phase, which was not environmentally favourable for the direct usage in diesel engines. Analysis showed that the ketones and the phenols in aqueous phase participated in HTL process as reactants, and the acids promoted the hydrolysis of protein in the sludge. Overall, the recycling of aqueous phase effectively improved the energy recovery and alleviated pollution of the sludge HTL.


Assuntos
Esgotos , Água , Temperatura , Reciclagem , Solventes , Biocombustíveis/análise , Biomassa
18.
ACS Omega ; 7(34): 29813-29822, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36061678

RESUMO

The motion behavior of particles impacting on the liquid surface can affect the capture efficiency of particles. It was found that there are three kinds of motion behaviors after particle impact on the liquid surface: sinking, rebound, and oscillation. In this paper, the processes of micron fly-ash particles impacting on the liquid surface were experimentally studied under normal temperature and pressure. The impact of fly-ash particles on the liquid surface was simulated by a dynamic model. Based on force analysis, the dynamic model was developed and verified by experimental data to distinguish between three motion behaviors. Then, the sinking/rebound critical velocity and rebound/oscillation critical velocity were calculated by the dynamic model. The critical velocities of particles impacting on the liquid surface under different particle sizes, receding angles, and surface tension coefficients were analyzed. As the particle size increased, sinking/rebound critical velocity and rebound/oscillation critical velocity decreased. As the receding angle increased, sinking/rebound critical velocity remained unchanged, and the rebound/oscillation critical velocity decreased. As the liquid surface tension coefficient increased, sinking/rebound critical velocity and rebound/oscillation critical velocity increased. On this basis, the behaviors of particles impacting on the liquid at low velocity were analyzed.

19.
Bioresour Technol ; 343: 126094, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34624473

RESUMO

Links between carbon/nitrogen (C/N) ratio, synergy and microbial characteristics of anaerobic co-digestion of food waste (FW), cattle manure (CS) and corn straw (CS) were investigated. Digesters with 100% CS, 25% FW + 75% CS, 25% CM + 75% CS suffered acid inhibition, in close association with unbalanced C/N and the resulting recessions of Syntrophomonadaceae and Methanosaeta. Co-digestion overcame C/N imbalance and achieved multiple synergies. Process performance had a positive correlation with Syntrophomonadaceae. Digester with 75% FW + 25% CS had most Syntrophomonadaceae (26.7%) and methane yield (467.3-507.6 mL/g VS) among co-digestion trials. Synergy was greater under higher load and exhibited a good correlation with C/N ratio. Co-digestion of FW, CM and CS (2:2:1) with suitable C/N ratio (20.79) obtained the greatest synergistic rate (14.6%). Unstable systems were improved by adjusting C/N ratio to 30 via urea, which stimulated Methanosarcina growth therefore enhanced methanogenic pathway diversity and ensured powerful methanogenic functions.


Assuntos
Esterco , Eliminação de Resíduos , Anaerobiose , Animais , Biocombustíveis , Reatores Biológicos , Carbono , Bovinos , Digestão , Alimentos , Metano , Nitrogênio , Zea mays
20.
Artigo em Inglês | MEDLINE | ID: mdl-36078840

RESUMO

With the rapid development of industry, the disposal of industrial solid waste needs to be solved urgently in China. Thus, an effective disposal method should be proposed to recycle these solid wastes in an environmentally friendly and sustainable manner. In this paper, ceramsite was prepared from sewage sludge (SS), magnesite tailings (MTs), and coal gangue (CG). The influence of the material ratio and sintering temperature on the properties of the ceramsite was investigated. The results show that the ceramsite had better properties when the following parameters were used: a ratio of SS: CG: MT of 4.5:4:1.5; a sintering temperature of 1250 °C; a compressive strength of 11.2 MPa (or it can be rounded to 11; our major remark relates to significant figures, and they should be up to 2-3 figures, according to measurement errors); a water absorption of 3.54%; and apparent and bulk densities of 1.19 and 0.81 g/cm3, respectively. The strength was superior to more than twice the 900-density grade prescribed by the Chinese national standard. After sintering, most of the heavy metals in the ceramsite mainly existed in the form of residue state (FD), meaning that they were highly stable. The leaching concentrations of Zn and Ni from the ceramsite were 0.72 and 0.25 mg/L lower than the prescribed regulatory limits (2.0 and 0.1 mg/L). The overall pollution toxicity index (OPTI) was only 240, less than that of raw pellets, indicating that the environmental risk is low. Not only did the ceramsite, prepared from SS, CG, and MT, exhibit excellent chemical properties, but it also proved to be an environmentally safe material. Therefore, it is an effective approach to realize the collaborative treatment of SS, CG, and MT by preparing ceramsite.


Assuntos
Metais Pesados , Esgotos , Carvão Mineral , Misturas Complexas , Resíduos Industriais , Magnésio , Metais Pesados/química , Esgotos/química , Resíduos Sólidos
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