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1.
Environ Sci Technol ; 58(8): 3823-3829, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38366998

RESUMO

Despite the large carbon footprint of livestock production, animal protein consumption has grown over the past several decades, necessitating new approaches to sustainable animal protein production. In this techno-economic analysis, single cell protein (SCP) produced via gas fermentation of carbon dioxide, oxygen, and hydrogen is studied as an animal feed source to replace fishmeal or soybean meal. Using wind-powered water electrolysis to produce hydrogen and oxygen with carbon dioxide captured from corn ethanol, the minimum selling price (MSP) of SCP is determined to be $2070 per metric ton. An emissions comparison between SCP, fishmeal, and soybean meal shows that SCP has a carbon intensity as low as 0.73 kg CO2-equiv/kg protein, while fishmeal and soybean meal have an average carbon intensity of 2.72 kg CO2-equiv/kg protein and 0.85 kg CO2-equiv/kg protein, respectively. Moreover, SCP production would occupy 0.4% of the land per ton of protein produced compared to soybean meal and would disturb less than 0.1% of the marine ecosystem currently disturbed by fishmeal harvesting practices. These results show promise for the future economic viability of SCP as a protein source in animal feed and indicate significant environmental benefits compared to other animal feed protein sources.


Assuntos
Dióxido de Carbono , Proteínas Alimentares , Ecossistema , Animais , Fermentação , Glycine max , Hidrogênio , Oxigênio
2.
J Ind Microbiol Biotechnol ; 46(11): 1531-1545, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31270700

RESUMO

The economic viability of the biorefinery concept is limited by the valorization of lignin. One possible method of lignin valorization is biological upgrading with aromatic-catabolic microbes. In conjunction, lignin monomers can be produced by fast pyrolysis and fractionation. However, biological upgrading of these lignin monomers is limited by low water solubility. Here, we address the problem of low water solubility with an emulsifier blend containing approximately 70 wt% Tween® 20 and 30 wt% Span® 80. Pseudomonas putida KT2440 grew to an optical density (OD600) of 1.0 ± 0.2 when supplied with 1.6 wt% emulsified phenolic monomer-rich product produced by fast pyrolysis of red oak using an emulsifier dose of 0.076 ± 0.002 g emulsifier blend per g of phenolic monomer-rich product. This approach partially mitigated the toxicity of the model phenolic monomer p-coumarate to the microbe, but not benzoate or vanillin. This study provides a proof of concept that processing of biomass-derived phenolics to increase aqueous availability can enhance microbial utilization.


Assuntos
Fenóis/metabolismo , Óleos de Plantas/metabolismo , Polifenóis/metabolismo , Pseudomonas putida/metabolismo , Biomassa , Fracionamento Químico , Emulsões , Lignina/metabolismo
3.
Am J Hematol ; 92(1): 77-81, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27761932

RESUMO

The clinical efficacy of hydroxyurea in patients with sickle cell anemia (SCA) has been well established. However, data about its clinical effectiveness in practice is limited. We evaluated the clinical effectiveness of hydroxyurea in a large pediatric population using a retrospective cohort, pre-post treatment study design to control for disease severity selection bias. The cohort included children with SCA (SS, Sß0 thalassemia) who received care at Children's Healthcare of Atlanta (CHOA) and who initiated hydroxyurea in 2009-2011. Children on chronic transfusions, or children with inadequate follow up data and/or children who had taken hydroxyurea in the 3 years prior were excluded. For each patient healthcare utilization, laboratory values, and clinical outcomes for the 2-year period prior to hydroxyurea initiation were compared to those 2 years after initiation. Of 211 children with SCA who initiated hydroxyurea in 2009-2011, 134 met eligibility criteria. After initiation of hydroxyurea, rates of hospitalizations, pain encounters, and emergency department visits were reduced by 47% (<0.0001), 36% (P = 0.0001) and 43% (P < 0.0001), respectively. Average hemoglobin levels increased by 0.7 g/dl (P < 0.0001). Hydroxyurea effectiveness was similar across gender, insurance types and age, although there was a slightly greater reduction in hospitalizations in younger children. Am. J. Hematol. 92:77-81, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Anemia Falciforme/tratamento farmacológico , Antidrepanocíticos/uso terapêutico , Hospitalização/tendências , Hidroxiureia/uso terapêutico , Adolescente , Fatores Etários , Anemia Falciforme/sangue , Antidrepanocíticos/administração & dosagem , Criança , Estudos de Coortes , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Hidroxiureia/administração & dosagem , Masculino , Prontuários Médicos , Estudos Retrospectivos , Resultado do Tratamento
4.
J Ind Microbiol Biotechnol ; 44(9): 1279-1292, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28551747

RESUMO

Lignocellulosic biomass is an appealing feedstock for the production of biorenewable fuels and chemicals, and thermochemical processing is a promising method for depolymerizing it into sugars. However, trace compounds in this pyrolytic sugar syrup are inhibitory to microbial biocatalysts. This study demonstrates that hydrophobic inhibitors damage the cell membrane of ethanologenic Escherichia coli KO11+lgk. Adaptive evolution was employed to identify design strategies for improving pyrolytic sugar tolerance and utilization. Characterization of the resulting evolved strain indicates that increased resistance to the membrane-damaging effects of the pyrolytic sugars can be attributed to a glutamine to leucine mutation at position 29 of carbon storage regulator CsrA. This single amino acid change is sufficient for decreasing EPS protein production and increasing membrane integrity when exposed to pyrolytic sugars.


Assuntos
Membrana Celular/metabolismo , Escherichia coli/citologia , Escherichia coli/metabolismo , Açúcares/metabolismo , Biomassa , Escherichia coli/genética , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Etanol/metabolismo , Fermentação , Glutamina/genética , Glutamina/metabolismo , Leucina/genética , Leucina/metabolismo , Lignina/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas Repressoras/química , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
5.
Environ Sci Technol ; 49(24): 14688-95, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26545153

RESUMO

This study investigates a novel strategy of reducing carbon emissions from coal-fired power plants through co-firing bio-oil and sequestering biochar in agricultural lands. The heavy end fraction of bio-oil recovered from corn stover fast pyrolysis is blended and co-fired with bituminous coal to form a bio-oil co-firing fuel (BCF). Life-cycle greenhouse gas (GHG) emissions per kWh electricity produced vary from 1.02 to 0.26 kg CO2-eq among different cases, with BCF heavy end fractions ranging from 10% to 60%, which corresponds to a GHG emissions reduction of 2.9% to 74.9% compared with that from traditional bituminous coal power plants. We found a heavy end fraction between 34.8% and 37.3% is required to meet the Clean Power Plan's emission regulation for new coal-fired power plants. The minimum electricity selling prices are predicted to increase from 8.8 to 14.9 cents/kWh, with heavy end fractions ranging from 30% to 60%. A minimum carbon price of $67.4 ± 13 per metric ton of CO2-eq was estimated to make BCF power commercially viable for the base case. These results suggest that BCF co-firing is an attractive pathway for clean power generation in existing power plants with a potential for significant reductions in carbon emissions.


Assuntos
Biocombustíveis , Dióxido de Carbono/análise , Sequestro de Carbono , Carvão Mineral , Centrais Elétricas , Carvão Vegetal , Comércio , Eletricidade , Meio Ambiente , Efeito Estufa , Modelos Teóricos , Centrais Elétricas/economia , Zea mays
6.
Appl Microbiol Biotechnol ; 98(20): 8413-31, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25204861

RESUMO

The environmental impact of agricultural waste from the processing of food and feed crops is an increasing concern worldwide. Concerted efforts are underway to develop sustainable practices for the disposal of residues from the processing of such crops as coffee, sugarcane, or corn. Coffee is crucial to the economies of many countries because its cultivation, processing, trading, and marketing provide employment for millions of people. In coffee-producing countries, improved technology for treatment of the significant amounts of coffee waste is critical to prevent ecological damage. This mini-review discusses a multi-stage biorefinery concept with the potential to convert waste produced at crop processing operations, such as coffee pulping stations, to valuable biofuels and bioproducts using biochemical and thermochemical conversion technologies. The initial bioconversion stage uses a mutant Kluyveromyces marxianus yeast strain to produce bioethanol from sugars. The resulting sugar-depleted solids (mostly protein) can be used in a second stage by the oleaginous yeast Yarrowia lipolytica to produce bio-based ammonia for fertilizer and are further degraded by Y. lipolytica proteases to peptides and free amino acids for animal feed. The lignocellulosic fraction can be ground and treated to release sugars for fermentation in a third stage by a recombinant cellulosic Saccharomyces cerevisiae, which can also be engineered to express valuable peptide products. The residual protein and lignin solids can be jet cooked and passed to a fourth-stage fermenter where Rhodotorula glutinis converts methane into isoprenoid intermediates. The residues can be combined and transferred into pyrocracking and hydroformylation reactions to convert ammonia, protein, isoprenes, lignins, and oils into renewable gas. Any remaining waste can be thermoconverted to biochar as a humus soil enhancer. The integration of multiple technologies for treatment of coffee waste has the potential to contribute to economic and environmental sustainability.


Assuntos
Biocombustíveis , Resíduos Industriais , Biotecnologia/métodos , Biotransformação , Café , Manipulação de Alimentos/métodos , Kluyveromyces/crescimento & desenvolvimento , Kluyveromyces/metabolismo , Rhodotorula/crescimento & desenvolvimento , Rhodotorula/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Saccharum , Yarrowia/crescimento & desenvolvimento , Yarrowia/metabolismo , Zea mays
7.
Inhal Toxicol ; 26(2): 113-27, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24495247

RESUMO

Alkaline earth silicate (AES) wools are low-biopersistence high-temperature insulation wools. Following prolonged periods at high temperatures they may devitrify, producing crystalline silica (CS) polymorphs, including cristobalite, classified as carcinogenic to humans. Here we investigated the cytotoxic and genotoxic significance of cristobalite present in heated AES wools. Primary rat alveolar macrophages were incubated in vitro for 2 h with 200 µg/cm² unheated/heated calcium magnesium silicate wools (CMS1, CMS2, CMS3; heat-treated for 1 week at, or 4 weeks 150 °C below, their respective classification temperatures) or magnesium silicate wool (MS; heated for 24 h at 1260 °C). Types and quantities of CS formed, and fiber size distribution and shape were determined by X-ray diffraction and electron microscopy. Lactate dehydrogenase release and alkaline and hOGG1-modified comet assays were used, ± aluminum lactate (known to quench CS effects), for cytotoxicity/genotoxicity screening. Cristobalite content of wools increased with heating temperature and duration, paralleled by decreases in fiber length and changes in fiber shape. No marked cytotoxicity, and nearly no (CMS) or only slight (MS) DNA-strand break induction was observed, compared to the CS-negative control Al2O3, whereas DQ12 as CS-positive control was highly active. Some samples induced slight oxidative DNA damage, but no biological endpoint significantly correlated with free CS, quartz, or cristobalite. In conclusion, heating of AES wools mediates changes in CS content and fiber length/shape. While changes in fiber morphology can impact biological activity, cristobalite content appears minor or of no relevance to the intrinsic toxicity of heated AES wools in short-term assays with rat alveolar macrophages.


Assuntos
Poluentes Atmosféricos/toxicidade , Macrófagos Alveolares/efeitos dos fármacos , Fibras Minerais/toxicidade , Silicatos/toxicidade , Dióxido de Silício/toxicidade , Poluentes Atmosféricos/química , Animais , Células Cultivadas , Ensaio Cometa , Materiais de Construção , Dano ao DNA , Feminino , Temperatura Alta , Humanos , Microscopia Eletrônica de Varredura , Ratos , Ratos Wistar , Silicatos/química , Fatores de Tempo , Vitrificação
8.
Nat Rev Chem ; 8(5): 376-400, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38693313

RESUMO

Electrification to reduce or eliminate greenhouse gas emissions is essential to mitigate climate change. However, a substantial portion of our manufacturing and transportation infrastructure will be difficult to electrify and/or will continue to use carbon as a key component, including areas in aviation, heavy-duty and marine transportation, and the chemical industry. In this Roadmap, we explore how multidisciplinary approaches will enable us to close the carbon cycle and create a circular economy by defossilizing these difficult-to-electrify areas and those that will continue to need carbon. We discuss two approaches for this: developing carbon alternatives and improving our ability to reuse carbon, enabled by separations. Furthermore, we posit that co-design and use-driven fundamental science are essential to reach aggressive greenhouse gas reduction targets.

9.
J Environ Qual ; 52(3): 630-640, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36825766

RESUMO

Biochar has been used to address several environmental problems and may be efficacious as a carrier of N-fertilizer in slow-release N-fertilizer (SRF) formulations. Our objective was to compare the efficacy of SRF pellets formulated with different mass ratios of biochar and urea with traditional N-fertilizers for improving N use efficiency by maize (Zea mays L.) grown under greenhouse conditions. Two different soil types, four SRF formulations with different biochar-to-urea (BCN) ratios (1:2 BCN, 1:3 BCN, 1:4 BCN, and 1:6 BCN), three traditional N-fertilizers (urea, urea ammonium nitrate, and S-coated urea), and unfertilized controls for each soil were tested. The accelerated urea release test showed significantly less loss of urea for the SRF over time than the traditional N-fertilizers. The biochar-based SRF formulations significantly (p < 0.05) decreased nitrate leaching loss for both soils relative to the traditional fertilizers. All the SRF formulations increased maize shoot (1%-34%) and root (0%-23%) biomass, N-recovery efficiency (17%-50%), and soil potential mineralizable-N relative to urea and S-coated urea. The results also indicate that the BCN ratio in the SRF formulation can be used to influence the timing of N release and plant N uptake. The results of the greenhouse study suggest that biochar-based SRFs have potential agronomic and environmental benefits; however, more research is needed to assess their agronomic value under field conditions.


Assuntos
Fertilizantes , Zea mays , Nitrogênio/análise , Agricultura , Solo , Carvão Vegetal , Ureia
10.
Regul Toxicol Pharmacol ; 64(2): 296-304, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22975085

RESUMO

Intensive study of the natural asbestiform minerals that cause human diseases, and the consequent understanding of their hazardous characteristics, has enabled the development of manufactured fibres whose physical and/or chemical properties, in particular as they relate to biopersistence, have been adjusted to minimize possible harm to health. A strong driver for the developmentof new high temperature insulation materials wasthe perception of the toxicity of refractory ceramic fibres (RCF)and their classification in the EU as a category 2 carcinogen under Directive 67/548/EEC. Such classification carries with it the requirement for substitution by less hazardous materials. This paper focuses on the development of alkaline earth silicate (AES) wools as a new class of high temperature insulation with the capability of such substitution in a number of applications. These wools have only a low potential to cause harm because they do not persist in lung tissue once deposited, and have produced minimal effects in experimental test systems. AES wools are increasingly being used in a wide range of high temperature applications.


Assuntos
Silicatos/toxicidade , Animais , Biotransformação , Carcinógenos/química , Carcinógenos/farmacocinética , Carcinógenos/toxicidade , Temperatura Alta , Humanos , Silicatos/química , Silicatos/farmacocinética
11.
J Environ Qual ; 41(4): 1115-22, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22751053

RESUMO

A potential concern about the use of fast pyrolysis rather than slow pyrolysis biochars as soil amendments is that they may contain high levels of bioavailable C due to short particle residence times in the reactors, which could reduce the stability of biochar C and cause nutrient immobilization in soils. To investigate this concern, three corn ( L.) stover fast pyrolysis biochars prepared using different reactor conditions were chemically and physically characterized to determine their extent of pyrolysis. These biochars were also incubated in soil to assess their impact on soil CO emissions, nutrient availability, microorganism population growth, and water retention capacity. Elemental analysis and quantitative solid-state C nuclear magnetic resonance spectroscopy showed variation in O functional groups (associated primarily with carbohydrates) and aromatic C, which could be used to define extent of pyrolysis. A 24-wk incubation performed using a sandy soil amended with 0.5 wt% of corn stover biochar showed a small but significant decrease in soil CO emissions and a decrease in the bacteria:fungi ratios with extent of pyrolysis. Relative to the control soil, biochar-amended soils had small increases in CO emissions and extractable nutrients, but similar microorganism populations, extractable NO levels, and water retention capacities. Corn stover amendments, by contrast, significantly increased soil CO emissions and microbial populations, and reduced extractable NO. These results indicate that C in fast pyrolysis biochar is stable in soil environments and will not appreciably contribute to nutrient immobilization.


Assuntos
Carvão Vegetal/química , Incineração/métodos , Solo/química , Microbiologia do Solo , Temperatura , Fatores de Tempo , Água/química , Zea mays
12.
Appl Microbiol Biotechnol ; 91(6): 1519-23, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21789490

RESUMO

Thermochemical processing of biomass by fast pyrolysis provides a nonenzymatic route for depolymerization of biomass into sugars that can be used for the biological production of fuels and chemicals. Fermentative utilization of this bio-oil faces two formidable challenges. First is the fact that most bio-oil-associated sugars are present in the anhydrous form. Metabolic engineering has enabled utilization of the main anhydrosugar, levoglucosan, in workhorse biocatalysts. The second challenge is the fact that bio-oil is rich in microbial inhibitors. Collection of bio-oil in distinct fractions, detoxification of bio-oil prior to fermentation, and increased robustness of the biocatalyst have all proven effective methods for addressing this inhibition.


Assuntos
Bactérias/metabolismo , Biocombustíveis/microbiologia , Biotecnologia/métodos , Carboidratos/química , Fungos/metabolismo , Bactérias/genética , Biocombustíveis/análise , Fermentação , Fungos/genética , Temperatura Alta , Hidrólise
13.
Lancet Haematol ; 8(5): e323-e333, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33838113

RESUMO

BACKGROUND: For decades, patients with sickle cell disease have had only a limited number of therapies available. In 2019, voxelotor (1500 mg), an oral once-daily sickle haemoglobin polymerisation inhibitor, was approved in the USA for the treatment of sickle cell disease in patients aged 12 years and older on the basis of HOPE trial data. To further describe the applicability of voxelotor as a treatment for this chronic illness, we report the long-term efficacy and safety of this drug at 72 weeks of treatment; the conclusion of the placebo-controlled HOPE trial. METHODS: HOPE is an international, randomised, double-blind, placebo-controlled, phase 3 trial done at 60 clinical sites in Canada, Egypt, France, Italy, Jamaica, Kenya, Lebanon, Netherlands, Oman, Turkey, the USA, and the UK. Patients (aged 12-65 years) with confirmed sickle cell disease, a haemoglobin concentration of 5·5-10·5 g/dL at enrolment, and who had between one and ten vaso-occlusive crisis events in the previous 12 months were enrolled. Patients receiving regularly scheduled transfusion therapy, who had received a transfusion in the previous 60 days, or who had been admitted to hospital for a vaso-occlusive crisis in the previous 14 days were excluded. Patients were randomly assigned (1:1:1) to receive either once-daily oral voxelotor 1500 mg, voxelotor 900 mg, or placebo for 72 weeks. Randomisation was done centrally by use of an interactive web response system, stratified by baseline hydroxyurea use (yes vs no), age group (adolescents [12 to <18 years] vs adults [18 to 65 years]), and geographic region (North America vs Europe vs other). The primary endpoint (already reported) was the proportion of patients who achieved a haemoglobin response at week 24. In this final analysis, we report prespecified long-term efficacy assessments by intention to treat, including changes in haemoglobin concentrations from baseline to week 72, changes in the concentration of haemolysis markers (absolute and percentage reticulocytes, indirect bilirubin concentrations, and lactate dehydrogenase concentrations) from baseline to week 72, the annualised incidence of vaso-occlusive crises, and patient functioning, as assessed with the Clinical Global Impression of Change (CGI-C) scale. Safety was assessed in patients who received at least one dose of treatment (modified intention-to-treat population). This trial is registered with ClinicalTrials.gov, NCT03036813. FINDINGS: Between Dec 5, 2016, and May 3, 2018, 449 patients were screened, of whom 274 were randomly assigned to the voxelotor 1500 mg group (n=90), the voxelotor 900 mg group (n=92), or the placebo group (n=92). At week 72, the adjusted mean change in haemoglobin concentration from baseline was 1·0 g/dL (95% CI 0·7 to -1·3) in the voxelotor 1500 mg group, 0·5 g/dL (0·3 to -0·8) in the voxelotor 900 mg group, and 0·0 g/dL (-0·3 to 0·3) in the placebo group, with a significant difference observed between the voxelotor 1500 mg group and the placebo group (p<0·0001), and between the voxelotor 900 mg group and the placebo group (p=0·014). Significant improvements in markers of haemolysis, as assessed by the difference in adjusted mean percentage change from baseline at week 72 versus placebo, were observed in the voxelotor 1500 mg group in indirect bilirubin concentrations (-26·6% [95% CI -40·2 to -12·9]) and percentage of reticulocytes (-18·6% [-33·9 to -3·3]). The proportion of patients in the voxelotor 1500 mg group who were rated as "moderately improved" or "very much improved" at week 72 with the CGI-C was significantly greater than in the placebo group (39 [74%] of 53 vs 24 [47%] of 51; p=0·0057). Serious adverse events unrelated to sickle cell disease were reported in 25 (28%) of 88 patients in the voxelotor 1500 mg group, 20 (22%) of 92 patients in the voxelotor 900 mg group, and 23 (25%) of 91 patients in the placebo group. Grade 3 or 4 adverse events were infrequent (ie, occurred in <10% of patients); anaemia occurred in five or more patients (two [2%] patients in the voxelotor 1500 mg group, seven [8%] patients in the voxelotor 900 mg group, and three [3%] patients in the placebo group). Of all 274 patients, six (2%) deaths occurred during the study (two deaths in each treatment group), all of which were judged as unrelated to treatment. INTERPRETATION: Voxelotor 1500 mg resulted in rapid and durable improvements in haemoglobin concentrations maintained over 72 weeks and has potential to address the substantial morbidity associated with haemolytic anaemia in sickle cell disease. FUNDING: Global Blood Therapeutics.


Assuntos
Anemia Falciforme/tratamento farmacológico , Benzaldeídos/uso terapêutico , Pirazinas/uso terapêutico , Pirazóis/uso terapêutico , Adolescente , Adulto , Idoso , Benzaldeídos/efeitos adversos , Criança , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Seguimentos , Genótipo , Cefaleia/etiologia , Hemoglobina Falciforme/genética , Hemoglobina Falciforme/metabolismo , Hemoglobinas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Efeito Placebo , Pirazinas/efeitos adversos , Pirazóis/efeitos adversos , Resultado do Tratamento , Adulto Jovem
14.
Environ Sci Technol ; 44(20): 7970-4, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20836548

RESUMO

Through cation exchange capacity assay, nitrogen adsorption-desorption surface area measurements, scanning electron microscopic imaging, infrared spectra and elemental analyses, we characterized biochar materials produced from cornstover under two different pyrolysis conditions, fast pyrolysis at 450 °C and gasification at 700 °C. Our experimental results showed that the cation exchange capacity (CEC) of the fast-pyrolytic char is about twice as high as that of the gasification char as well as that of a standard soil sample. The CEC values correlate well with the increase in the ratios of the oxygen atoms to the carbon atoms (O:C ratios) in the biochar materials. The higher O:C ratio was consistent with the presence of more hydroxyl, carboxylate, and carbonyl groups in the fast pyrolysis char. These results show how control of biomass pyrolysis conditions can improve biochar properties for soil amendment and carbon sequestration. Since the CEC of the fast-pyrolytic cornstover char can be about double that of a standard soil sample, this type of biochar products would be suitable for improvement of soil properties such as CEC, and at the same time, can serve as a carbon sequestration agent.


Assuntos
Recuperação e Remediação Ambiental , Solo , Adsorção , Microscopia Eletrônica de Varredura , Nitrogênio/química , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Front Chem ; 8: 656, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32850668

RESUMO

Mitigation of potentially hazardous and malodor compounds emitted from animal waste is needed to improve the sustainability of livestock agriculture. Bacteria control the generation of these compounds and also depend on the pH of manure. Influencing swine manure pH, especially on the liquid-air interface, may lead to a reduction of emission of odorous and hazardous compounds. The objective of this experiment was to test highly alkaline and porous (HAP) modified biochar with pH = 9.2 and red oak (RO) biochar with pH = 7.5 influence on swine manure pH acquired from the outdoor storage and deep pit storage under a barn. HAP and RO biochars were topically applied on the outdoor-stored (pH = 7.55), and pit (pH = 8.00) manures and spatial pH (every 1 mm of depth) were measured on days 0, 2, and 4. Results showed that HAP biochar increased outdoor-stored manure pH on day 4, particularly within the top 10 mm of depth, where pH ranged from 7.79 to 8.90, while in the case of RO pH ranged between 7.46 and 7.66, i.e., similar to control (7.57-7.64). Both biochars decreased pit-stored manure pH within the top 10 mm of depth (in comparison with the control pH of 8.36-8.47) to 8.19-8.30 (HAP), and 8.18-8.29 (RO) on day 4. However, differences were not considerable. The reason for the insignificant effect of biochars on pit manure was likely due to its higher buffer capacity in comparison with the outdoor-stored manure.

17.
J Hazard Mater ; 162(2-3): 1430-7, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18640777

RESUMO

The research focused on the production of a complex wastewater coagulant containing polymeric sulfates of aluminum and iron from fly ash. At the same time, SO(2) in the simulated flu gas was removed by absorption in a fly ash slurry and oxidized with sodium chlorate. Extraction efficiency of iron and aluminum oxides from fly ash was affected greatly by reaction temperature and time. The extraction efficiency increases as temperature increases. Removal efficiency of SO(2) was influenced by temperature, SO(2) feed concentration and feed gas dispersing method. The produced complex coagulant containing both polymeric ferric sulfate (PFS) and polymeric aluminum sulfate (PAS) was proven to be effective in removing total suspended solids (TSS) and turbidity in wastewater. The complex coagulant is more effective than conventional iron and aluminum sulfates in turbidity removal.


Assuntos
Carbono , Gases , Resíduos Industriais , Material Particulado , Poluentes da Água , Cinza de Carvão , Microscopia Eletrônica de Varredura
18.
Bioresour Technol ; 292: 121976, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31421591

RESUMO

Among the products of pyrolysis is an aqueous phase (AP), which contains a significant fraction of carbon but is too dilute to make recovery of this organic content cost-effectively. This study was to explore the use of AP for anaerobic digestion. Different treatment methods including overliming, Fenton's reagent oxidation, bleaching and activated carbon adsorption were investigated to reduce toxicity of AP. Overliming treatment increased biogas production up to 32-fold compared to non-treated AP. Enhancing the tolerance of the bacterial and archaeal community to the AP toxicity was also attempted with a directed evolution method, resulting the microbes' tolerance to AP from 5% to 14%. Directed evolution resulted a major bacterial taxa as Cloacimonetes, Firmicutes, and Chloroflexi, while shifted the predominant archaea shifted from acetoclastic to hydrogenotrophic methanogens. Collectively, the results demonstrated that combining feedstock treatment and directed evolution of the microbial community is an effective way for AP anaerobic digestion.


Assuntos
Reatores Biológicos , Pirólise , Anaerobiose , Archaea , Biomassa , Metano
19.
Ann Pharmacother ; 42(1): 131-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18056831

RESUMO

OBJECTIVE: To describe a case of an intellectually disabled patient who was diagnosed with autistic disorder (AD) and responded positively to buspirone, demonstrated by a reduction in target behaviors of self-injury, property destruction, and physical aggression. CASE SUMMARY: A 33-year-old, white, nonverbal, profoundly intellectually impaired woman (IQ <20-25), residing in a state-run facility, exhibited worsening aggressive behaviors associated with AD. These behaviors were characterized by a history of self-injurious behavior (eg, slapping and scratching herself); property destruction, including breaking windows; and head butting of staff and peers. Additional diagnoses included a seizure disorder, hyperprolactinemia, and osteoporosis. At the time of admission, her drug regimen included 3 atypical antipsychotic agents: risperidone, clozapine, and aripiprazole. Antipsychotic agents have been reported to lower the seizure threshold, and elevated prolactin levels have been associated with risperidone use. Aripiprazole and clozapine were discontinued on admission, and risperidone was discontinued one month later following increased behavioral deterioration. Buspirone was considered an appropriate replacement medication, as it has not been associated with elevated prolactin levels or a lowered seizure threshold, and was initiated at 15 mg/day. Significant reductions in aggression were noted following titration to a total daily dose of 90 mg. DISCUSSION: Buspirone is approved for treatment of generalized anxiety disorder in adults. Dopaminergic agonist/antagonist actions have been reported with use of higher doses. These receptor effects have been beneficial for aggressive behaviors in the AD population that were exhibited by our patient, but effectiveness for aggression in the intellectually disabled population is uncertain. In our patient, problematic behaviors associated with AD responded positively to buspirone. CONCLUSIONS: The reduction in target aggressive behaviors achieved with buspirone therapy allowed other treatment interventions to proceed more effectively in our patient. Clinicians may wish to consider use of buspirone in patients with AD who do not respond to or have risk factors for use of other therapy.


Assuntos
Ansiolíticos/uso terapêutico , Transtorno Autístico/tratamento farmacológico , Buspirona/uso terapêutico , Adulto , Agressão/efeitos dos fármacos , Antipsicóticos/uso terapêutico , Transtorno Autístico/fisiopatologia , Epilepsia/complicações , Feminino , Humanos , Hiperprolactinemia/complicações , Deficiência Intelectual/complicações , Deficiência Intelectual/tratamento farmacológico , Osteoporose/complicações , Comportamento Autodestrutivo/tratamento farmacológico , Comportamento Autodestrutivo/etiologia , Resultado do Tratamento
20.
Bioresour Technol ; 99(6): 1801-5, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17532624

RESUMO

Fuel ethanol production in corn dry milling plants is a rapidly expanding industrial sector. Whole stillage, the residue from the distillation of the fermented corn, is centrifuged and the concentrate, thin stillage, is found to have a chemical oxygen demand (COD) of approximately 75,000 mg/L. This thin stillage is partly recycled, but much of it needs to be evaporated to concentrate the solubles for addition to the animal feed coproduct from corn dry milling. This research is an exploration into lowering COD from thin stillage using ozonation as a simple single-step unit process to facilitate a larger reusable fraction. The ozonation would usually be a pretreatment before additional flocculation or biological treatment. Also, COD removal by ozonation with and without a catalyst has been studied. Three different application rates of ozone O(3,1)=7 mg/min, O(3,2)=21 mg/min, and O(3,3)=33 mg/min were used for 8h into samples of 2L each of three dilutions 20x, 30x and 40x. COD removal of 85% was observed with an ozone dosage of 4000 mg/L into a 40x-diluted sample. This would correspond to about 0.5 mg COD removed per mg ozone dosed. However, at lower dosages and smaller dilutions, more than 1mg COD removal was achieved per mg ozone dosed. Two different catalysts, Fe(II) and Fe(III), were used and the samples were ozonated for 4 h. Five different dosages of each of the two catalysts were used and better COD removal was observed compared to ozonation alone with all 5 dosages. COD removal rate was increased from 45% to 74% with Fe(III) and was increased to 77% with Fe(II). Up to 10mg/L COD was removed per mg O(3) dosed well below the maximum dosage. Both the catalysts resulted in almost the same improved COD removal rates when compared to ozonation alone.


Assuntos
Biotecnologia/métodos , Etanol/química , Fermentação , Oxigênio/química , Ozônio , Biodegradação Ambiental , Reatores Biológicos , Catálise , Desenho de Equipamento , Resíduos Industriais , Modelos Químicos , Oxidantes Fotoquímicos , Ozônio/química , Eliminação de Resíduos Líquidos/métodos , Água/química , Purificação da Água
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