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Heat stress (HS) has serious negative effects on plant development and has become a major threat to agriculture. A rapid transcriptional regulatory cascade has evolved in plants in response to HS. Nuclear Factor-Y (NF-Y) complexes are critical for this mechanism, but how NF-Y complexes are regulated remains unclear. In this study, we identified NF-YC10 (NF-Y subunit C10), a central regulator of the HS response in Arabidopsis thaliana, as a substrate of SUMOylation, an important post-translational modification. Biochemical analysis showed that the SUMO ligase SIZ1 (SAP AND MIZ1 DOMAIN-CONTAINING LIGASE1) interacts with NF-YC10 and enhances its SUMOylation during HS. The SUMOylation of NF-YC10 facilitates its interaction with and the nuclear translocation of NF-YB3, in which the SUMO interaction motif (SIM) is essential for its efficient association with NF-YC10. Further functional analysis indicated that the SUMOylation of NF-YC10 and the SIM of NF-YB3 are critical for HS-responsive gene expression and plant thermotolerance. These findings uncover a role for the SIZ1-mediated SUMOylation of NF-YC10 in NF-Y complex assembly under HS, providing new insights into the role of a post-translational modification in regulating transcription during abiotic stress responses in plants.
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Proteínas de Arabidopsis , Arabidopsis , Termotolerância , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Sumoilação , Ligases/genética , Ligases/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
Recent advancement in natural language processing (NLP) and medical imaging empowers the wide applicability of deep learning models. These developments have increased not only data understanding, but also knowledge of state-of-the-art architectures and their real-world potentials. Medical imaging researchers have recognized the limitations of only targeting images, as well as the importance of integrating multimodal inputs into medical image analysis. The lack of comprehensive surveys of the current literature, however, impedes the progress of this domain. Existing research perspectives, as well as the architectures, tasks, datasets, and performance measures examined in the present literature, are reviewed in this work, and we also provide a brief description of possible future directions in the field, aiming to provide researchers and healthcare professionals with a detailed summary of existing academic research and to provide rational insights to facilitate future research.
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Processamento de Linguagem Natural , Humanos , Inquéritos e QuestionáriosRESUMO
Copper-catalyzed conjugate addition is a classic method for forming new carbon-carbon bonds. However, copper has never showed catalytic activity for umpolung carbanions in hydrazone chemistry. Herein, we report a facile conjugate addition of hydrazone catalyzed by readily available copper complexes at room temperature. The employment of mesitylcopper(I) and electron-rich phosphine bidentate ligand is a key factor affecting reactivity. The reaction allows various aromatic hydrazones to react with diverse conjugated compounds to produce 1,4-adducts in yields of about 20 to 99%.
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BACKGROUND Online blended learning, also known as "smart classes", has benefits when compared with traditional teaching methods that use books and lectures. This study aimed to compare the use of the Smart Class teaching module with traditional teaching on the topic of psychosocial dysfunction during the training of undergraduate occupational therapy (OT) students in China. MATERIAL AND METHODS We recruited Grade 2017 OT students as the Smart Class teaching module group and Grade 2016 OT students as the Traditional Class teaching module group to participate in the study. The objective evaluation (assignment score, practical exam score, written exam score, and final score) and subjective evaluation (data from student questionnaires and information from interviews with the lead teacher and assistant teachers) were performed in both groups. RESULTS No significant difference was found in the final scores (P=0.874) and students' questionnaire results between the 2 groups. However, data from the student questionnaires and teacher interviews indicated a preference for combining the Smart Class teaching module and the Traditional Class teaching module. CONCLUSIONS The advantage of the Smart Class teaching module is that it can effectively integrate excellent teaching resources across geographical restrictions and it is conducive to promoting independent learning for students and all-around supervision for teaching. The Smart Class teaching module was comparable to traditional teaching methods for the training of undergraduate OT students in China, but was preferred by the students.
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Educação a Distância/métodos , Adolescente , Adulto , China , Currículo , Feminino , Humanos , Masculino , Estudantes de Medicina , Inquéritos e Questionários , Adulto JovemRESUMO
Metal-organic frameworks (MOFs) material with high surface area, good chemical stability and multi-functionality, has become an emerging adsorbent for water treatment. A novel kind of quaternary amine anionic-exchange MOFs UiO-66 namely UiO-66-NMe3+ was firstly synthesized for adsorptive removal of a widely used toxic herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) from aqueous solutions. The well-prepared UiO-66-NMe3+ MOFs were fully characterized, and then the main parameters affecting the adsorption process including solution pH, adsorbent dosage and coexisting anions were systematically investigated. The maximum adsorption capacity of UiO-66-NMe3+ toward 2,4-D reached as high as 279 mg g-1, much higher than that of pristine UiO-66 and aminated UiO-66. The adsorption mechanism could be attributed to the electrostatic interactions efficiently enhanced by the functionalization of quaternary amine groups, combining with the π-π conjugations between the linkers in MOFs and 2,4-D molecules, leading to the better adsorption performance of UiO-66-NMe3+. Additionally, the UiO-66-NMe3+ could be well regenerated by simple solvent washing and exhibited a slight decline of adsorption capacity after seven successive recycle. Furthermore, satisfactory adsorption capacity and reusability of the MOFs in environmental water samples were attained. Comparing with reported activated carbon and resin materials, the UiO-66-NMe3+ MOFs possessed higher adsorption capacity and shorter equilibrium time, as well as good reusability and practicality. The developed ion-exchange functionalized MOFs provided an ideal alternative for efficient adsorptive-removal of 2,4-D from complicated aqueous environment.
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Herbicidas , Estruturas Metalorgânicas , Poluentes Químicos da Água , Purificação da Água , Ácido 2,4-Diclorofenoxiacético , AdsorçãoRESUMO
Environmental estrogens have attracted great concerns. Recent studies have indicated that some hydroxylated polybrominated diphenyl ethers (HO-PBDEs) can interact with estrogen receptor (ER), and exhibit estrogenic activity. However, interactions between HO-PBDEs and ER are not well understood. In this work, molecular docking and molecular dynamics (MD) simulations were performed to characterize interactions of two HO-PBDEs (4'-HO-BDE30 and 4'-HO-BDE121) with ERα. Surflex-Dock was employed to reveal the probable binding conformations of the compounds at the active site of ERα; MD simulation was used to determine the detailed binding process. The driving forces of the binding between HO-PBDEs and ERα were van der Waals and electrostatic interactions. The decomposition of the binding free energy indicated that the hydrogen bonds between the residues Glu353, Gly521 and ligands were crucial for anchoring the ligands into the active site of ERα and stabilizing their conformations. The results showed that different interaction modes and different specific interactions with some residues were responsible for the different estrogenic activities of the two HO-PBDEs.
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Receptor alfa de Estrogênio/química , Éteres Difenil Halogenados/química , Simulação de Dinâmica Molecular , Receptor alfa de Estrogênio/metabolismo , Éteres Difenil Halogenados/metabolismo , Humanos , Hidroxilação , Modelos Moleculares , Ligação Proteica , Reprodutibilidade dos Testes , Poluentes Químicos da Água/químicaRESUMO
Recently, a novel biomass pulverization technology was proposed by our group. In this paper, further detailed studies of this technology were carried out. The effects of feed moisture and crusher operational parameters (rotor speed and blades gap) on product particle size distribution and energy consumption were investigated. The results showed that higher rotor speed and smaller blades gap could improve the hit probability between blades and materials and enhance the impacting and grinding effects to generate finer products, however, resulting in the increase of energy consumption. Under dry conditions finer particles were much more easily achieved, and there was a tendency for the specific energy to increase with increasing feed moisture. Therefore, it is necessary for the raw biomass material to be dried before pulverization.
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Biomassa , IndústriasRESUMO
BACKGROUND: Mucosa-associated lymphoid tissue (MALT) lymphoma, also known as extranodal marginal zone lymphoma, is more commonly detected in the stomach and rarely in the breast. Our study presented a clinical and pathological examination of a patient diagnosed with breast MALT lymphoma, supplemented with pertinent research, to offer guidance for the diagnosis and treatment of this condition. PEOPLE CONCERNS: The occurrence of breast MALT lymphoma has risen in the past decade, but its etiology, progression and treatment response are less well-studied. DIAGNOSIS: Breast MALT lymphoma was diagnosed by excisional biopsy and histopathology. INTERVENTIONS: Following breast MALT lymphoma diagnosis, the patient was transferred to the hematology department for further treatment, and she made the decision to continue observing. OUTCOMES: After 3 months of observation, the patient remained asymptomatic. CONCLUSION: Breast MALT lymphoma is an indolent disease with an asymptomatic presentation, There are no standardized treatment guidelines for breast MALT lymphoma, treatment must be tailored to the patient willingness to treat and the severity of the disease. Hence, in order to give patients a better chance of cure, more research is needed to explore its pathogenesis and more clinical trials are needed investigate the treatment of this disease.
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Neoplasias da Mama , Linfoma de Zona Marginal Tipo Células B , Feminino , Humanos , Linfoma de Zona Marginal Tipo Células B/terapia , Linfoma de Zona Marginal Tipo Células B/tratamento farmacológico , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/terapia , Neoplasias da Mama/patologia , BiópsiaRESUMO
A well-defined Ru(II)-PNP complex demonstrated high activity in the anti-Markovnikov hydroalkylation of nonpolarized terminal alkenes via hydrazones. Hydrazone served as a carbanion equivalent to combine with the electrophilic alkene substrate upon activation by the ruthenium catalyst, forming a new C-C bond in a concerted pathway with N2 as the only theoretical byproduct. Experimental and computational studies suggested the existence of a push-pull interaction that activated the alkene for hydrazone addition and then deduced the mechanism.
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Urea-formaldehyde (UF) resin is difficult to degrade and classified as hazardous organic waste. To address this concern, the co-pyrolysis behavior of UF resin with pine sawdust (PS) was studied, and the adsorption properties of pyrocarbon were evaluated with Cr (VI). Thermogravimetric analysis revealed that adding a small amount of PS can improve the pyrolysis behavior of UF resin. Based on the Flynn Wall Ozawa (FWO) method, the kinetics and activation energy values were estimated. It was observed that when the amount of UF resin exceeded twice that of PS, the activation energy of the reaction decreased, and they acted synergistically. The characterization of pyrocarbon samples showed that the specific surface area increased with the increase of temperature, while the content of functional groups showed the opposite trend. Intermittent adsorption experiments showed that 5UF + PS400 achieved 95% removal of 50 mg/L Cr (VI) at 0.6 g/L dosage and at pH 2. The adsorption process was consistent with the Langmuir isotherm and pseudo-second-order kinetics, and the maximum adsorption was 143.66 mg/g at 30 â. Furthermore, the adsorption process consisted of electrostatic adsorption, chelation, and redox reaction. Overall, this study provides a useful reference for the co-pyrolysis of UF resin and the adsorption capacity of pyrocarbon.
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Pinus , Poluentes Químicos da Água , Adsorção , Pirólise , Polímeros , Cinética , Formaldeído , Ureia , Cromo/química , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio , Carvão Vegetal/químicaRESUMO
Recently, there are still some controversial mechanisms of the 3D electrocatalytic oxidation system, which would probably confound its industrial application. From the conventional viewpoint, the Ti4O7 material may be the desired particle electrodes in the 3D system since its high oxygen evolution potential favors the production of â¢OH via H2O splitting reaction at the anode side of Ti4O7 particle electrodes. In fact, the incorporation of Ti4O7 particles showed phenol degradation of 88% and COD removal of 51% within 120 min, under the optimum conditions at energy consumption of 0.668 kWh g-1 COD, the performance of which was much lower than those in many previous literatures. In contrast, the prepared carbon black-polytetrafluoroethylene composite (CB-PTFE) particles with abundant oxygen-containing functional groups could yield considerable amounts of H2O2 (200 mg L-1) in the 3D reactor and achieved a complete degradation of phenol and COD removal of 80% in the presence of Fe2+, accompanying a low energy consumption of only 0.080 kWh g-1 COD. It was estimated that only 20% of Ti4O7 particles near the anode attained the potential over 2.73 V/SCE at 30 mA cm-2 based on the potential test and simulation, responsible for the low yield of â¢OH via the H2O splitting on Ti4O7 (1.74 × 10-14 M), and the main role of Ti4O7 particle electrodes in phenol degradation was through direct oxidation. For the CB-PTFE-based 3D system, current density of 10 mA cm-2 was sufficient for all the CB-PTFE particles to attain cathodic potential of -0.67 V/SCE, conducive to the high yield of H2O2 and â¢OH (9.11 × 10-14 M) in the presence of Fe2+, and the â¢OH-mediated indirect oxidation was mainly responsible for the phenol degradation. Generally, this study can provide a deep insight into the 3D electrocatalytic oxidation technology and help to develop the high-efficiency and cost-efficient 3D technologies for industrial application.
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Peróxido de Hidrogênio , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Fenóis , Fenol , Oxirredução , EletrodosRESUMO
The sulfur poisoning mechanism of low-temperature SCR de-NOx catalyst has always been one of the hot spots in academic circles. By studying the surface sulfur poisoning mechanism, low-temperature catalysts can be developed pertinently. In this paper, the mechanism of sulfur poisoning on the surface of LaMnO3 catalyst was studied by DFT method, and the adsorption process of sulfur oxides on the surface and its influence on SCR reaction process, as well as the morphology and decomposition process of ammonium sulfate on the surface were calculated. The results show that sulfur oxides will be adsorbed on the surface and occupy the adsorption site, which will adversely affect the subsequent SCR reaction. At the same time, ammonium sulfate will accumulate on the catalyst surface, which will lead to sulfur poisoning.
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Amônia , Óxidos de Enxofre , Sulfato de Amônio , Oxirredução , Catálise , EnxofreRESUMO
The high-efficiency and environmentally-friendly electro-oxidation (EO) would lose its competitive edge because of the production of oxychloride by-products (ClOx-), which has not yet drawn significant attention in academic and engineering communities. In this study, the negative effects of the electrogenerated ClOx- were compared among four commonly used anode materials (BDD, Ti4O7, PbO2 and Ru-IrO2) in terms of ClOx- interference on the evaluation of electrochemical COD removal performance and biotoxicity. Apparently, the COD removal performance of various EO systems were highly enhanced with increasing current density in the presence of Cl-, e.g., the amounts of COD removed by various EO systems from the phenol solution with an initial COD content of 280 mg L-1 at 40 mA cm-2 within 120 min decreased in the order: Ti4O7 of 265 mg L-1 > BDD of 257 mg L-1 > PbO2 of 202 mg L-1 > Ru-IrO2 of 118 mg L-1, which was different from the case with the absence of Cl- (BDD of 200 mg L-1 > Ti4O7 of 112 mg L-1 > PbO2 of 108 mg L-1 > Ru-IrO2 of 80 mg L-1) and the results after removing ClOx- by anoxic sulfite-based method (BDD of 205 mg L-1 > Ti4O7 of 160 mg L-1 > PbO2 of 153 mg L-1 > Ru-IrO2 of 99 mg L-1). These results can be ascribed to the ClOx- interference on COD evaluation, the extent of which decreased in the order: ClO3- > ClO- (where ClO4- cannot impact COD test). The highest overrated electrochemical COD removal performance of Ti4O7 may be associated with its relatively high production of ClO3- and the low mineralization extent. The chlorella inhibition ratio of ClOx- decreased in the order: ClO- > ClO3- >> ClO4-, which accounted for the biotoxicity increasement of the treated water (PbO2 68%, Ti4O7 56%, BDD 53%, Ru-IrO2 25%). Generally, the inevitable problems of overrated electrochemical COD removal performance and biotoxicity increasement induced by ClOx- should deserve significant attention and effective countermeasures should be also developed when employing EO process for wastewater treatment.
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In recent years, the continuous development of electronic chips and the increasing integration of devices have led to extensive research on the thermal properties of ultrathin metallic materials. In particular, accurate characterization of their thermal transport properties has become a research hotspot. In this paper, we review the characterization methods of metallic nanomaterials, focusing on the principles of the transient electrothermal (TET) technique and the differential TET technique. By using the differential TET technique, the thermal conductivity, electrical conductivity, and Lorenz number of extremely confined metallic nanostructures can be characterized with high measurement accuracy. At present, we are limited by the availability of existing coating machines that determine the thickness of the metal films, but this is not due to the measurement technology itself. If a material with a smaller diameter and lower thermal conductivity is used as the substrate, much thinner nanostructures can be characterized.
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Deliberate addition of mildly oxidative chlorate (ClO3-), so-called "chemical oxygen demand (COD) remover", into wastewater in China or electrochemical production of ClO3- from Cl- induces the false COD reduction, which would bring about false appearance of effluents meeting the COD discharge standards. In this study, an easy sulfite-based reduction method was developed for the first time to remove ClO3- from the water samples before COD determination to eliminate this interference of ClO3-. In this reaction system, keeping the reaction temperature of sulfite reducing ClO3- at 60 °C was crucial for fast ClO3- removal rate, fixed molar [sulfite]ini/[chlorate]ini ratio value and the synchronous exhaustion of sulfite and ClO3-, which were of great significance for the real application of this improved COD determination method. The ClO3- interference on COD determination could be successfully eliminated after 20 min reduction of ClO3- by sulfite at pHini 4.0â¼6.0 with the molar [sulfite]ini/[chlorate]ini ratio value in the range of 5â¼6 when concentration of ClO3- was below 5 mM. Despite of the involvement of SO4·- in the sulfite reducing ClO3- system, the degradation of organic matters by SO4·- could be greatly impeded due to the lessened dissolved oxygen for SO4·- production at high reaction temperature and the scavenging of SO4·- by sulfite. In this reaction system, ClO2, ClO2- and ClO- were also generated and could be further reduced by sulfite stoichiometrically via oxygen transfer process with Cl- as the final product. In general, this study pioneered an effective, fast and convenient method for COD determination of the ClO3--laden wastewaters and evaluating the real electrochemical wastewater treatment performance in terms of COD removal.
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Poluentes Químicos da Água , Purificação da Água , Análise da Demanda Biológica de Oxigênio , Cloratos/análise , Oxirredução , Oxigênio , Sulfitos , Águas Residuárias , Purificação da Água/métodosRESUMO
Macrolide antibiotics (MAs), as a typical emerging pollutant, are widely detected in environmental media. When entering the environment, MAs can interfere with the growth, development and reproduction of organisms, which has attracted extensive attention. However, there are few reviews on the occurrence characteristics, migration and transformation law, ecotoxicity and related removal technologies of MAs in the environment. In this work, combined with the existing relevant research, the migration and transformation law and ecotoxicity characteristics of MAs in the environment are summarized, and the removal mechanism of MAs is clarified. Currently, most studies on MAs are based on laboratory simulation experiments, and there are few studies on the migration and transformation mechanism between multiphase states. In addition, the cost of MAs removal technology is not satisfactory. Therefore, the following suggestions are put forward for the future research direction. The migration and transformation process of MAs between multiphase states (such as soil-water-sediment) should be focused on. Apart from exploring the new treatment technology of MAs, the upgrading and coupling of existing MAs removal technologies to meet emission standards and reduce costs should also be concerned. This review provides some theoretical basis and data support for understanding the occurrence characteristics, ecotoxicity and removal mechanism of MAs.
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Poluentes Ambientais , Poluentes Químicos da Água , Antibacterianos/toxicidade , Macrolídeos , Solo , Poluentes Químicos da Água/análiseRESUMO
Polybrominated diphenyl ethers (PBDEs) widely existing in the environment can pose a serious threat to the ecological safety. However, the influence of PBDEs on methane production by excess sludge (ES) and kitchen waste (KW) anaerobic co-digestion and its mechanism is not clear. To fill this gap, in this work, the co-digestion characteristics of ES and KW exposed to different levels of PBDEs at medium temperature were investigated in sequencing batch reactor, and the related mechanisms were also revealed. The results showed that PBDEs reduced methane production and the proportion of methane in the biogas. Methane yield decreased from 215.3 mL/g· volatile suspended solids (VSS) to 161.5 mL/(g·VSS), accompanied by the increase of PBDE content from 0 to 8.0 mg/Kg. Volatile fatty acid (VFA) yield was also inhibited by PBDEs; especially when PBDEs were 8.0 mg/Kg, VFA production was only 215.6 mg/g VSS, accounting for 75.7% of that in the control. Mechanism investigation revealed PBDEs significantly inhibited the processes of hydrolysis, acidogenesis, acetogenesis, and methanogenesis. Further study showed that PBDEs could inhibit the degradation and bioavailability of ES and KW, but it had a greater inhibition on the utilization of KW. Enzyme activity investigation revealed that all the key enzyme activities related to methane production were suppressed by PBDEs.
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Éteres Difenil Halogenados , Esgotos , Anaerobiose , Reatores Biológicos , Digestão , Ácidos Graxos Voláteis/metabolismo , Metano/metabolismoRESUMO
Acid whey is a by-product generated in large quantities during dairy processing, and is characterized by its low pH and high chemical oxygen demand. Due to a lack of reliable disposal pathways, acid whey currently presents a major sustainability challenge to the dairy industry. The study presented in this paper proposes a solution to this issue by transforming yogurt acid whey (YAW) into potentially palatable and marketable beverages through yeast fermentation. In this study, five prototypes were developed and fermented by Kluyveromyces marxianus, Brettanomyces bruxellensis, Brettanomyces claussenii, Saccharomyces cerevisiae (strain: Hornindal kveik), and IOC Be Fruits (IOCBF) S. cerevisiae, respectively. Their fermentation profiles were characterized by changes in density, pH, cell count, and concentrations of ethanol and organic acids. The prototypes were also evaluated on 26 sensory attributes, which were generated through a training session with 14 participants. While S. cerevisiae (IOCBF) underwent the fastest fermentation (8 days) and B. claussenii the slowest (21 days), K. marxianus and S. cerevisiae (Hornindal kveik) showed similar fermentation rates, finishing on day 20. The change in pH of the fermentate was similar for all five strains (from around 4.45 to between 4.25 and 4.31). Cell counts remained stable throughout the fermentation for all five strains (at around 6 log colony-forming units (CFU)/mL) except in the case of S. cerevisiae (Hornindal kveik), which ultimately decreased by 1.63 log CFU/mL. B. bruxellensis was the only strain unable to utilize all of the sugars in the substrate, with residual galactose remaining after fermentation. While both S. cerevisiae (IOCBF)- and B. claussenii-fermented samples were characterized by a fruity apple aroma, the former also had an aroma characteristic of lactic acid, dairy products, bakeries and yeast. A chemical odor characteristic of petroleum, gasoline or solvents, was perceived in samples fermented by B. bruxellensis and K. marxianus. An aroma of poorly aged or rancid cheese or milk also resulted from B. bruxellensis fermentation. In terms of appearance and mouthfeel, the S. cerevisiae (IOCBF)-fermented sample was rated the cloudiest, with the heaviest body. This study provides a toolkit for product development in a potential dairy-based category of fermented alcoholic beverages, which can increase revenue for the dairy industry by upcycling the common waste product YAW.
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This work documents the annealing effect on the thermal conductivity of nanotube film (CNTB) and carbon nanotube fiber (CNTF). The thermal properties of carbon nanotube samples are measured by using the transient electro-thermal (TET) technique, and the experimental phenomena are analyzed based on numerical simulation. During the current annealing treatment, CNTB1 always maintains the negative temperature coefficient of resistance (TCR), and its thermal diffusivity increases gradually. When the annealing current is 200 mA, it increases by 33.62%. However, with the increase of annealing current, the TCR of CNTB2 changes from positive to negative. The disparity between CNTB2 and CNTB1 suggests that they have different physical properties and even structures along their lengths. The high-level thermal diffusivity of CNTB2 and CNTF are 2.28-2.46 times and 1.65-3.85 times higher than the lower one. The results show that the decrease of the thermal diffusivity for CNTB2 and CNTF is mainly caused by enhanced Umklapp scattering, the high thermal resistance and torsional sliding during high temperature heating.
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The combustion mechanism of biogas mixture is unclear, which leads to the lack of basis for the control of operating parameters. Combustion characteristics and reaction path of typical low calorific value biogas with variation of preheating temperature and air equivalence ratio (Φ) are discussed in this paper. Preheating can not only improve the flame propagation speed and flame temperature, but also increase the proportion of NO in the product at the end of combustion flame. To some extent, improving combustion efficiency and NOx control are contradictory operating parameters. The amount of NO increases with the increase in flame distance. The maximum value of NO appears when Φ is 1.1. NO formation rate is improved by preheating the biogas. The paths of N2 â N2O âNO, N2 â NNH âNO, and N2 âNO are all enhanced. When the equivalence ratio changes from 1.0 to 0.8, NO formation rates decrease.