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Fullerene C60 is an all-carbon cage molecule with rich physicochemical properties. It is highly symmetric and hydrophobic, which can be used as a building block for the preparation of amphiphiles that self-assemble into diverse supramolecular structures in aqueous solutions. Meanwhile, C60 is also lipophobic, which is different from the alkyl chains in traditional surfactants. By attaching alkyl chains to the C60 sphere, a new type of lipophobic-lipophilic amphiphiles can be constructed which undergo self-assembly in n-alkanes. When inorganic clusters such as polyoxometalate are linked to the C60 sphere, organic-inorganic hybrids will be obtained which can self-assemble in polar organic solvents. Pristine C60 has also been modified by polar groups such as hydroxy and carboxy, which are linked to hydrophobic moieties and form a new class of amphiphiles. In this review, the self-assembly of C60-based amphiphiles in aqueous and nonaqueous solutions will be summarized. The characteristics exhibited by C60-based amphiphiles during the self-assembly will be discussed with close comparison to traditional surfactants, and the influences of the aggregate formation on the physicochemical properties of the C60 sphere will be described. Finally, a brief summary will be given together with a promising perspective in near future.
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Long non-coding RNAs (lncRNAs) are crucial modulators in a variety of biological processes, such as gene expression, development, and immune defense. However, little is known about the function of lncRNAs in the development of Asian honey bee (Apis cerana) larval guts. Here, on the basis of our previously obtained deep-sequencing data from the 4-, 5-, and 6-day-old larval guts of A. cerana workers (Ac4, Ac5, and Ac6 groups), an in-depth transcriptome-wide investigation was conducted to decipher the expression pattern, regulatory manners, and potential roles of lncRNAs during the developmental process of A. cerana worker larval guts, followed by the verification of the relative expression of differentially expressed lncRNAs (DElncRNAs) and the targeting relationships within a competing endogenous RNA (ceRNA) axis. In the Ac4 vs. Ac5 and Ac5 vs. Ac6 comparison groups, 527 and 498 DElncRNAs were identified, respectively, which is suggestive of the dynamic expression of lncRNAs during the developmental process of larval guts. A cis-acting analysis showed that 330 and 393 neighboring genes of the aforementioned DElncRNAs were respectively involved in 29 and 32 functional terms, such as cellular processes and metabolic processes; these neighboring genes were also respectively engaged in 246 and 246 pathways such as the Hedgehog signaling pathway and the Wnt signaling pathway. Additionally, it was found that 79 and 76 DElncRNAs as potential antisense lncRNAs may, respectively, interact with 72 and 60 sense-strand mRNAs. An investigation of competing endogenous RNA (ceRNA) networks suggested that 75 (155) DElncRNAs in the Ac4 vs. Ac5 (Ac5 vs. Ac6) comparison group could target 7 (5) DEmiRNAs and further bind to 334 (248) DEmRNAs, which can be annotated to 33 (29) functional terms and 186 (210) pathways, including 12 (16) cellular- and humoral-immune pathways (lysosome pathway, necroptosis, MAPK signaling pathway, etc.) and 11 (10) development-associated signaling pathways (Wnt, Hippo, AMPK, etc.). The RT-qPCR detection of five randomly selected DElncRNAs confirmed the reliability of the used sequencing data. Moreover, the results of a dual-luciferase reporter assay were indicative of the binding relationship between MSTRG.11294.1 and miR-6001-y and between miR-6001-y and ncbi_107992440. These results demonstrate that DElncRNAs are likely to modulate the developmental process of larval guts via the regulation of the source genes' transcription, interaction with mRNAs, and ceRNA networks. Our findings not only yield new insights into the developmental mechanism underlying A. cerana larval guts, but also provide a candidate ceRNA axis for further functional dissection.
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MicroRNAs , RNA Longo não Codificante , Abelhas/genética , Animais , Larva/genética , Larva/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proteínas Hedgehog/genética , Reprodutibilidade dos Testes , RNA Mensageiro/genética , Redes Reguladoras de Genes , MicroRNAs/genéticaRESUMO
Electric field enhanced oxalic acid (H2C2O4) washing was conducted to examine the simultaneously removal efficiency of heavy metals (HMs) and chlorine, especially insoluble chlorine from municipal solid waste incineration fly ash (MSW FA). Results show that chlorine and HMs can be effectively removed with a total chlorine, As, Ni and Zn removal rate of 99.10%, 79.08%, 75.42% and 71.43%, when the electrode exchange frequencies is 40 Hz, current density is 50 mA/cm2, H2C2O4 adding amount is 0.5 mol/L and the reaction time is 4 h. Insoluble chlorine removal efficiency is up to 95.32%, much higher than reported studies. And the chlorine content in the residue is lower than 0.14%. Meanwhile, HMs removal efficiency is remarkable, 41.62%-67.51% higher than that of water washing. The high-efficient removal effect is caused by the constantly changing direction of electrons hitting the fly ash surface, which provides more escape channels for internal chlorine and HMs. These results proved that electric field enhanced oxalic acid washing could be a promising method for removing contaminants from MSWI fly ash.
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Metais Pesados , Eliminação de Resíduos , Incineração , Resíduos Sólidos , Cinza de Carvão , Cloro/química , Ácido Oxálico , Metais Pesados/análise , Cloretos , Carbono , Material ParticuladoRESUMO
As carbon-based nanomaterials, water-soluble C60 derivatives have potential applications in various fields of biomedicine. In this study, a water-soluble fullerene C60 derivative bearing alanine residues (Ala-C60) was synthesized. The effects of Ala-C60 on neural stem cells (NSCs) as seed cells were explored. Ala-C60 can promote the proliferation of NSCs, induce NSCs to differentiate into neurons, and inhibit the migration of NSCs. Most importantly, the Ala-C60 can significantly increase the cell viability of NSCs treated with hydrogen peroxide (H2O2). The glutathioneperoxidase (GSH-Px) and superoxide dismutase (SOD) activities and glutathione (GSH) content increased significantly in NSCs treated even by 20 µM Ala-C60. These findings strongly indicate that Ala-C60 has high potential to be applied as a scaffold with NSCs for regeneration in nerve tissue engineering for diseases related to the nervous system.
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Fulerenos , Células-Tronco Neurais , Alanina/farmacologia , Proliferação de Células , Células Cultivadas , Fulerenos/farmacologia , Peróxido de Hidrogênio/farmacologia , Água/farmacologiaRESUMO
Western honey bee (Apis mellifera), a eusocial insect with a superior economic and ecological value, is widely used in the beekeeping industry throughout the world. As a new class of non-coding RNAs (ncRNAs), circular RNAs (circRNAs) participate in the modulation of considerable biological processes, such as the immune response via diverse manners. Here, the identification, characteristic investigation, and molecular verification of circRNAs in the Apis mellifera ligustica larval guts were conducted, and the expression pattern of larval circRNAs during the Ascosphaera apis infection was analyzed, followed by the exploration of the potential regulatory part of differentially expressed circRNAs (DEcircRNAs) in host immune responses. A total of 2083 circRNAs in the larval guts of A. m. ligustcia were identified, with a length distribution ranging from 106 nt to 92,798 nt. Among these, exonic circRNAs were the most abundant type and LG1 was the most distributed chromosome. Additionally, 25, 14, and 30 up-regulated circRNAs as well as 26, 25, and 62 down-regulated ones were identified in the A. apis-inoculated 4-, 5-, and 6-day-old larval guts in comparison with the corresponding un-inoculated larval guts. These DEcircRNAs were predicted to target 35, 70, and 129 source genes, which were relative to 12, 23, and 20 GO terms as well as 11, 10, and 27 KEGG pathways, including 5 cellular and humoral immune pathways containing apoptosis, autophagy, endocytosis, MAPK, Toll, and Imd signaling pathways. Furthermore, complex competing endogenous RNA (ceRNA) regulatory networks were detected to be formed among DEcircRNAs, DEmiRNAs, and DEmRNAs. The Target DEmRNAs were engaged in 24, 20, and 25 functional terms as well as 62, 80, and 159 pathways, including several vital immune defense-associated pathways, namely the lysosome, endocytosis, phagosome, autophagy, apoptosis, MAPK, Jak-STAT, Toll, and Imd signaling pathways. Finally, back-splicing sites within 15 circRNAs and the difference in the 9 DEcircRNAs' expression between un-inoculated and A. apis-inoculated larval guts were confirmed utilizing molecular methods. These findings not only enrich our understanding of bee host-fungal pathogen interactions, but also lay a foundation for illuminating the mechanism underlying the DEcircRNA-mediated immune defense of A. m. ligustica larvae against A. apis invasion.
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Abelhas , Onygenales , RNA Circular , Animais , Abelhas/genética , Abelhas/microbiologia , Imunidade , Larva/genética , Larva/microbiologia , Onygenales/patogenicidade , RNA Circular/genéticaRESUMO
A robust superhydrophobic brass mesh was fabricated based on a low-energy surface and a roughness on the nano/micro-meter scale. It was carried out by the forming of hydroxyapatite (HP) coatings on its surface through a constant current electro-deposition process, followed by immersion in fluoroalkylsilane solution. Surface morphology, composition and wetting behavior were investigated by field-emission scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), high speed camera, and contact angle goniometer. Under optimal conditions, the resulting brass mesh exhibited superhydrophobicity, excellent anti-corrosion (η = 91.2%), and anti-scaling properties. While the surfactant liquid droplets of tetradecyl trimethyl ammonium bromide (TTAB) with different concentration were dropped on the superhydrophobic surface, maximum droplet rebounding heights and different contact angles (CAs) were observed and measured from side-view imaging. The plots of surfactant-concentration-maximum bounding height/CA were constructed to determine its critical-micelle-concentration (CMC) value. Close CMC results of 1.91 and 2.32 mM based on the determination of maximum rebounding height and CAs were obtained. Compared with its theoretical value of 2.1 mM, the relative errors are 9% and 10%, respectively. This indicated that the novel application based on the maximum rebounding height could be an alternative approach for the CMC determination of other surfactants.
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Durapatita , Tensoativos , Cobre , Durapatita/química , Propriedades de Superfície , Tensoativos/química , Molhabilidade , ZincoRESUMO
In this study, electric field and ball milling were used to leach Mn2+ from low-grade pyrolusite (LGP). The effects of current density, reaction time, reaction temperature, ball-to-powder weight ratio, and ball milling time on the leaching efficiency of Mn2+ from LGP as well as the leaching mechanism were systematically studied. The results showed that the combined use of electric field and ball milling enhanced the leaching of Mn2+ from LGP. The leaching efficiency of Mn2+ reached 97.79% under the optimum conditions of LGP-to-pyrite mass ratio of 1:0.18, current density of 30 mA/cm2, LGP-to-H2SO4 mass ratio of 1:0.4, liquid-to-solid ratio of 5:1, ball-to-powder weight ratio of 1:1, ball milling time of 2 h, temperature of 80 °C, and leaching duration of 120 min. This value was 25.95% higher than that attained without ball milling and 41.45% higher than that attained when neither ball milling nor electric field was employed. Pyrite was fully oxidized to generate additional SO42- and Fe3+, and was further hydrolyzed to form jarosite (KFe3(SO4)2(OH)6) and hydronium jarosite (Fe3(SO4)2(OH)5·2H2O) via ball milling and electric field application. Moreover, the electric field changed the surface charge distribution of the mineral particles and promoted collisions between them as well as the collapse of the crystal lattice, further improving the leaching efficiency of Mn2+ from LGP. This study provided a new method for leaching Mn from LGP.
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Manganês/química , Modelos Químicos , Compostos Férricos , Ferro , Compostos de Manganês , Óxidos , Sulfatos , SulfetosRESUMO
BACKGROUND: Previous reports have mainly focused on the volatiles in citrus fruits, and there have been few reports about the volatiles in citrus leaves and flowers. However, citrus leaves and flowers are also rich in volatile compounds with unique aromas. Here, to investigate the volatiles in citrus leaves and flowers, volatile profiling was performed on leaves from 62 germplasms and flowers from 25 germplasms. RESULTS: In total, 196 and 82 volatile compounds were identified from leaves of 62 citrus germplasms and flowers of 25 citrus germplasms, respectively. The dominant volatile terpenoids were more diverse in citrus leaves than in peels. A total of 34 volatile terpenoids were commonly detected in the leaves of at least 20 germplasms, among which 31 were overaccumulated in the leaves of wild or semiwild germplasms. This result was consistent with the high expression levels of five genes and one key gene of the mevalonate and 2-C-methyl-D-erythritol-4-phosphate (MEP) biosynthetic pathways, respectively, as well as the low expression levels of geranylgeranyl diphosphate synthase of the MEP pathway, relative to the levels in cultivars. Fully open flowers showed increased levels of four terpene alcohols and a decrease in sabinene content compared with balloon-stage flowers, especially in sweet orange. A monoterpene synthase gene was identified and functionally characterized as a sabinene synthase in vitro. CONCLUSIONS: Collectively, our results suggest that 31 important terpenoids are abundant in wild or semiwild citrus germplasms, possibly because of a negative effect of domestication on the volatiles in citrus leaves. The sweet smell of fully open flowers may be attributed to increased levels of four terpene alcohols. In addition, a sabinene synthase gene was identified by combined transcriptomic and metabolomic analyses.
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Citrus/genética , Terpenos/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Citrus/metabolismo , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Metabolômica , Odorantes , Folhas de Planta/metabolismo , Transcriptoma/genéticaRESUMO
Scutellariae radix (Scutellaria baicalensis Georgi, SR) and coptidis rhizoma (Coptis chinensis Franch, CR) are both widely used traditional Chinese medicines and have been used together to treat T2DM with synergistic effects in the clinical practices for thousands of years, but their combination mechanism is not clear. Accumulating evidences have implicated gut microbiota as important targets for the therapy of T2DM. Thus, this study aimed to unravel the cooperation mechanism of SR and CR on the amelioration of T2DM based on the systematic analysis of metagenome and metabolome of gut microbiota. Bacterial communities were analyzed based on high-throughput 16S rRNA gene sequencing. Furthermore, ultra high-performance liquid chromatography coupled with quadrupole time of flight mass spectrometry (UPLC-Q-TOF-MS) was used to analyze variations of microbial metabolites in feces and the contents of short chain fatty acids (SCFAs) in the cecum were determined by a gaschromatography-flame ionization detector (GC-FID). 16S rRNA gene sequencing results revealed that T2DM rats treated with SR, CR, and the combination of SR and CR (SC) exhibited changes in the composition of the gut microbiota. The SCFAs-producing bacteria such as Bacteroidales S24-7 group_norank, [Eubacterium] nodatum group, Parasutterella, Prevotellaceae UCG-001, Ruminiclostridium, and Ruminiclostridium 9 in T2DM rats were notably enriched after treatment with SR, CR, and their combination. In contrast, secondary bile acid-producing bacteria such as Escherichia-Shigella strongly decreased in numbers. The perturbance of metabolic profiling in T2DM rats was obviously improved after treatment, exhibiting a lower level of secondary bile acids and a numerical increase of microbially derived SCFAs. Moreover, the correlation analysis illustrated a close relationship among gut microbiota, its metabolites, and T2DM-related indexes. The findings indicated that the crosstalk between microbiota-derived metabolites and the host played an important role in the progress of T2DM and might provide a novel insight regarding gut microbiota and its metabolites as potential new targets of traditional Chinese medicines. Furthermore, this work also suggested that the integration of various omics methods and bioinformatics made a useful template for drug mechanism research.
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Diabetes Mellitus Experimental/prevenção & controle , Medicamentos de Ervas Chinesas/administração & dosagem , Microbioma Gastrointestinal/efeitos dos fármacos , Glicolipídeos/metabolismo , Scutellaria baicalensis/química , Animais , Coptis chinensis , Diabetes Mellitus Experimental/fisiopatologia , Combinação de Medicamentos , Ácidos Graxos Voláteis/análise , Fezes/química , Metabolismo dos Lipídeos , Masculino , Medicina Tradicional Chinesa , Metabolômica , RNA Ribossômico 16S , RatosRESUMO
Ulcerative colitis (UC), a kind of inflammatory bowel disease, is generally characterized by chronic, persistent, relapsing, and nonspecific ulceration of the bowel, which is widespread in the world. Although the pathogenesis of UC is multifactorial, growing evidence has demonstrated that gut microbiota and its metabolites are closely related to the development of UC. Lizhong decoction (LZD), a well-known classical Chinese herbal prescription, has been used to clinically treat UC for long time, but its mechanism is not clear. In this study, 16S rRNA gene sequencing combining with untargeted metabolomics profiling was used to investigate how LZD worked. Results indicated that LZD could shape the gut microbiota structure and modify metabolic profiles. The abundance of opportunistic pathogens such as Clostridium sensu stricto 1, Enterobacter, and Escherichia-Shigella correlated with intestinal inflammation markedly decreased, while the levels of beneficial bacteria including Blautia, Muribaculaceae_norank, Prevotellaceae UCG-001, and Ruminiclostridium 9 elevated in various degrees. Additionally, fecal metabolite profiles reflecting microbial activities showed that adenosine, lysoPC(18:0), glycocholic acid, and deoxycholic acid notably decreased, while cholic acid, α-linolenic acid, stearidonic acid, and L-tryptophan significantly increased after LZD treatment. Hence, based on the systematic analysis of 16S rRNA gene sequencing and metabolomics of gut flora, the results provided a novel insight that microbiota and its metabolites might be potential targets for revealing the mechanism of LZD on amelioration of UC.Key Points ⢠The potential mechanism of LZD on the amelioration of UC was firstly investigated.⢠LZD could significantly shape the structure of gut microbiota.⢠LZD could notably modulate the fecal metabolic profiling of UC mice. Graphical abstract.
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Colite Ulcerativa/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Microbioma Gastrointestinal/efeitos dos fármacos , Metaboloma/efeitos dos fármacos , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Bactérias/metabolismo , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/metabolismo , Colite Ulcerativa/microbiologia , Sulfato de Dextrana/toxicidade , Medicamentos de Ervas Chinesas/farmacologia , Fezes/química , Fezes/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
BACKGROUND: A study conducted on elderly Korean men showed that a high serum triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio was associated with a high risk of developing sarcopenia. We aimed to determine such an association in community-dwelling Chinese adults. METHODS: From May 2016 to August 2017, we conducted a cross-sectional study on Chinese adults at the First Affiliated Hospital of Wenzhou Medical University. Univariate and multivariate logistic regression analyses were applied to evaluate a possible relationship between TG/HDL-C ratio and sarcopenia occurrence. RESULTS: We included 2613 adults in this study, with 13.85% presenting with sarcopenia. The odds ratios (ORs) for TG and HDL-C were 0.67 (95% confidence interval [CI]: 0.51-0.87), and 1.97 (95% CI: 1.49-2.61), respectively. Moreover, TG/HDL-C ratio was independently associated with sarcopenia status (OR: 0.63; 95% CI: 0.49-0.81). CONCLUSIONS: We found that TG and HDL-C were, respectively, negatively and positively associated with sarcopenia occurrence rate in community-dwelling Chinese adults. However, a negative association was found between sarcopenia occurrence rate and TG/HDL-C ratio.
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HDL-Colesterol/sangue , Sarcopenia/sangue , Triglicerídeos/sangue , Adulto , Idoso , China/epidemiologia , HDL-Colesterol/metabolismo , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Curva ROC , Sarcopenia/epidemiologia , Inquéritos e QuestionáriosRESUMO
In this study, a new electrochemical method was used to simultaneously efficient removal of Mn2+ and NH4+-N in wastewater with Cu plate as cathode. The effects of various reaction parameters on the concentrations of Mn2+, NH4+-N and by-products (NO3--N and NO2--N, free chlorine and residual chlorine), as well as the removal mechanism were investigated. The results showed that the removal efficiencies of Mn2+ and NH4+-N were 99.1% and 92.9%, and the concentrations of NO3--N, NO2--N, free chlorine and residue chlorine were 0.73 mg/L, 0.15 mg/L, 0.13 mg/L and 0.63 mg/L reacting for 3 h at room temperature, respectively, when the current density was 10 mA/cm2, the mass ratio of ClO- and Cl- was 1:1, the initial pH was 9. The concentrations of Mn2+, NH4+-N and by-products in wastewater met the integrated wastewater discharge standard (GB8978-1996). In addition, spherical manganese oxide was deposited on the anode plate, and spherical manganese oxide collapsed over electrolysis time. Manganese was mainly removed in the form of MnO, Mn(OH)2 and MnO2. NH4+-N was mainly oxidized to N2. Economic evalution revealed that the treatment cost was 2.93 $/m3.
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Amônia/química , Compostos de Manganês/química , Óxidos/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Cloro , Cobre/química , Técnicas Eletroquímicas , Eletrodos , Eletrólise , Manganês/química , Nitrogênio/análise , Oxirredução , Águas Residuárias/químicaRESUMO
Electrolytic manganese residue (EMR) is a solid waste remained in filters after using sulfuric acid to leaching manganese carbonate ore. EMR contains high concentration of soluble manganese (Mn2+) and ammonia nitrogen (NH4+-N), which seriously pollutes the environment. In this study, a low cost of phosphate based binder for Mn2+ and NH4+-N stabilization in EMR by low grade-MgO (LG-MgO) and superphosphate was studied. The effects of different types of stabilizing agent on the concentrations of NH4+-N and Mn2+, the pH of the EMR leaching solution, stabilizing mechanisms of NH4+-N and Mn2+, leaching test and economic analysis were investigated. The results shown that the pH of the EMR leaching solution was 8.07, and the concentration of Mn2+ was 1.58 mg/L, both of which met the integrated wastewater discharge standard (GB8978-1996), as well as the concentration of NH4+-N decreased from 523.46 mg/L to 32 mg/L, when 4.5 wt.% LG-MgO and 8 wt.% superphosphate dosage were simultaneously used for the stabilization of EMR for 50 d Mn2+ and NH4+-N were mainly stabilized by Mn3(PO4)2·2H2O, MnOOH, Mn3O4, Mn(H2PO4)2·2H2O and NH4MgPO4·6H2O. Economic evaluation revealed that the treatment cost of EMR was $ 11.89/t. This study provides a low-cost materials for NH4+-N and Mn2+ stabilization in EMR.
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Amônia/química , Manganês/química , Amônia/análise , Carbonatos , Eletrólise , Eletrólitos/química , Poluentes Ambientais/análise , Manganês/análise , Nitrogênio/análise , Fosfatos/química , Resíduos Sólidos/análise , Águas Residuárias/químicaRESUMO
Luminescent metal nanoclusters (NCs) are emerging as a new class of functional materials that have rich physicochemical properties and wide potential applications. In recent years, it has been found that some metal NCs undergo aggregation-induced emission (AIE) and an interesting fluorescence-to-phosphorescence (F-P) switching in solutions. However, insights of both the AIE and the F-P switching remain largely unknown. Now, gelation of water soluble, atomically precise Ag9 NCs is achieved by the addition of antisolvent. Self-assembly of Ag9 NCs into entangled fibers was confirmed, during which AIE was observed together with an F-P switching occurring within a narrow time scale. Structural evaluation indicates the fibers are highly ordered. The self-assembly of Ag9 NCs and their photoluminescent property are thermally reversible, making the metal-organic gels good candidates for luminescent ratiometric thermometers.
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Biomineralization is a typical methodology developed by nature to produce calcium-based materials. A method mimicking this process has nowadays become popular for the preparation of artificial organic-inorganic hybrids. Here, Cu3(PO4)2 crystals with a flowerlike morphology have been prepared using water-soluble derivatives of fullerene C60 as templates. In a typical system, flowerlike crystals of Cu3(PO4)2 (denoted FLCs-Cu) were obtained by simply dropping an aqueous solution of CuSO4 into phosphate-buffered saline (PBS) containing a highly water-soluble multiadduct of C60 (fullerenol). The best condition for the preparation of FLCs-Cu appeared at 0.20 mg·mL-1 fullerenol and 0.10 mol·L-1 PBS. During the formation of FLCs-Cu, fullerenol acts as a template and its content in FLCs-Cu is trace (less than 5% by atom) as confirmed by scanning electron microscopy mapping and thermogravimetric analysis. This feature makes fullerenol reusable, and the FLCs-Cu can be prepared repeatedly using the same fullerenol aqueous solution at least 10 times without a noticeable change in the morphology. The N2 adsorption/desorption isotherm showed that the doping of fullerenol increased the specific surface area of the Cu3(PO4)2 crystal. When fullerenol was replaced by C60 monoadducts that are cofunctionalized with a pyrrolidine cation and oligo(poly(ethylene oxide)) chains, FLCs-Cu can form as well, indicating that the strategy of using water-soluble C60 derivative as a template to get FLCs-Cu is universal. As a typical example of practical applications, the photocatalytic activity of the FLCs-Cu was investigated toward the degradation of dyes including rhodamine B and rhodamine 6G. In both cases, efficient photodegradation has been confirmed.
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Amphiphilic derivatives of fullerene C60 are attractive from viewpoints of supramolecular chemistry and biomedicine. The establishment of relationships among the molecular structure, aggregation behavior and properties such as scavenging radicals of the amphiphilic C60 derivatives is the key to push these carbon nanomaterials to real applications. In this work, six monosubstituted C60 derivatives were synthesized by a one-step quaternization of their neutral precursors, which bear Percec monodendrons terminated with oligo(poly(ethylene oxide)) (o-PEO) chain(s). The main difference among the C60 derivatives lies in the number and substituted position of the o-PEO chain(s) within the Percec monodendron. Derivative with a 4-substitution of the o-PEO chain still showed limited solubility in water. Other derivatives possessing two or three o-PEO chains exhibited much improved solubilities and rich aggregation behavior in water. It was found that the formation of aggregates is regulated both by the number and the substituted pattern of the o-PEO chains. Typical morphologies include nanosheets, nanowires, vesicles, nanotubes, and nanorods. Although the structures of the C60 derivatives are different from those of traditional surfactants, their aggregation behavior can be also well explained by applying the theory of critical packing parameter. Interestingly, the capabilities of the C60 derivatives to scavenge the hydroxyl radicals (OH·-) followed the same order of their solubility in water, where the compound bearing three o-PEO chains with a 2,3,4-substitution got the champion quenching efficiency of â¼97.79% at a concentration of 0.15 mg·mL-1 (â¼0.11 mmol·L-1).
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Electrolytic manganese residue (EMR) is a solid waste generated in the process of producing electrolytic metal manganese and contains a lot of manganese and ammonia nitrogen. In this study, electrokinetic remediation (EK) of manganese and ammonia nitrogen from EMR were carried out by using pulse electric field (PE) in different agents, and sodium dodecyl benzene sulfonate (SDBS), citric acid (CA) and ethylene diamine tetraacetic acid (EDTA) were used as enhancement agents. The removal behavior of ammonia nitrogen and manganese under direct current field (DC) and PE, and the relationship between manganese fractionation and transport behavior, as well as the energy consumption were investigated. The results demonstrated that the removal efficiency of ammonia nitrogen and manganese using PE were higher than DC. SDBS, EDTA and CA could enhance electroosmosis and electromigration, and the sequence of enhancement agent effects were CA, SDBS, EDTA, distilled water. The highest removal efficiency of manganese and ammonia nitrogen were 94.74% and 88.20%, and the effective removal amount of manganese and ammonia nitrogen was 23.93 and 1.48â¯mg·wh-1, when CA and SDBS+CA was used as the enhancement agents, respectively. Moreover, electromigration was the main removal mechanism of manganese and ammonia nitrogen in the EK process.
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Amônia/química , Manganês/química , Nitrogênio/química , Benzenossulfonatos/química , Ácido Cítrico/química , Ácido Edético/química , Eletricidade , Eletrólise , Eletrólitos , Resíduos Sólidos/análiseRESUMO
Electrolytic metal manganese residue leachate (EMMRL) was produced from long-term deposition of electrolytic metal manganese residue. EMMRL contains huge amount of manganese and ammonia nitrogen which could seriously damage the ecological environment. In this study, a chemical equilibrium model-Visual MINTEQ was used to simultaneously optimize removal of manganese and ammonia nitrogen from EMMRL with chemical precipitation methods. In the laboratory experiment, the effect of different N: P ratios and pH were investigated, and the characterization of the precipitates was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscope (SEM). The results showed that over 99.9% manganese and 96.2% ammonia nitrogen were simultaneously removed, respectively, when molar ratio of N:P was 1:1.15 at pH 9.5. Moreover, the experimental results corresponded well with the model outputs with respect to ammonia nitrogen and manganese removal. Manganese was mainly removed in the form of MnHPO4·3H2O and manganite, and ammonia nitrogen was mainly removed in the form of struvite. Economic evaluation indicated the chemical precipitation methods can be applied in the factory when the price of precipitation was higher than 0.295 $/kg.
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Amônia/química , Manganês/química , Modelos Químicos , Nitrogênio/química , Gerenciamento de Resíduos/métodos , Poluentes Químicos da Água/química , Precipitação Química , Eletrólise , Resíduos Industriais , Compostos de Manganês/química , Metalurgia , Estruvita/químicaRESUMO
The speciation, bioavailability and environmental risk of heavy metals (HMs) in the hydrochar derived from hydrothermal carbonization (HTC) of swine manure were investigated in this study. The results indicated that the majority of HMs originally in swine manure were retained in the hydrochar by HTC, and CaO addition substantially reduced the HMs concentration in the hydrochar. HTC especially CaO assisted HTC significantly promoted the HMs transformation from the bioavailable fraction to the relatively stable fraction, and thus decreased their environmental risk in the hydrochar. Moreover, the Toxicity Characteristic Leaching Procedure and diethylenetriamine pentaacetic acid test revealed that the leachability and plant-bioavailability of HMs in swine manure were greatly declined by HTC especially for HTC with 15% CaO addition. The present study suggested that HTC was an effective disposal approach for swine manure from the perspective of HMs immobilization, especially for CaO assisted HTC.
Assuntos
Esterco , Metais Pesados , Animais , Disponibilidade Biológica , SuínosRESUMO
The aroma quality of citrus fruit is determined by volatile compounds, which bring about different notes to allow discrimination among different citrus species. However, the volatiles with various aromatic traits specific to different citrus species have not been identified. In this study, volatile profiles in the fruit peels of four citrus species collected from our previous studies were subjected to various analyses to mine volatile biomarkers. Principal component analysis results indicated that different citrus species could almost completely be separated. Thirty volatiles were identified as potential biomarkers in discriminating loose-skin mandarin, sweet orange, pomelo, and lemon, while 17 were identified as effective biomarkers in discriminating clementine mandarins from the other loose-skin mandarins and sweet oranges. Finally, 30 citrus germplasms were used to verify the classification based on ß-elemene, valencene, nootkatone, and limettin as biomarkers. The accuracy values were 90.0%, 96.7%, 96.7%, and 100%, respectively. This research may provide a novel and effective alternative approach to identifying citrus genetic resources.