209 research outputs found

    4-Anilino-3-nitro-N-phenyl­benzamide

    Get PDF
    In the title compound, C19H15N3O3, the anilino and benzamide rings make dihedral angles of 10.66 (16) and 50.39 (16)°, respectively, with the nitro-substituted benzene ring. The nitro group is slightly twisted by 11.49 (17)° with respect to the attached benzene ring. There is an intra­molecular N—H⋯O hydrogen bond forming an S(6) ring. In the crystal, weak inter­molecular N—H⋯O and C—H⋯O hydrogen bonds link the mol­ecules into a chain parallel to the b axis. Futhermore, weak slipped π–π inter­actions [centroid–centroid distance = 3.819 (2) Å, inter­planar distance = 3.567 Å and offset angle [how is the offset angle defined?] = 21°] between the anilino ring and its symmetry-related counterpart may help to stabilize the packing

    The Ecological Response of Carex lasiocarpa

    Get PDF
    The response of Carex lasiocarpa in riparian wetlands in Sanjiang Plain to the environmental gradient of water depth was analyzed by using the Gaussian Model based on the biomass and average height data, and the ecological water-depth amplitude of Carex lasiocarpa was derived. The results indicated that the optimum ecological water-depth amplitude of Carex lasiocarpa based on biomass was [13.45 cm, 29.78 cm], while the optimum ecological water-depth amplitude of Carex lasiocarpa based on average height was [2.31 cm, 40.11 cm]. The intersection of the ecological water-depth amplitudes based on biomass and height confirmed that the optimum ecological water-depth amplitude of Carex lasiocarpa was [13.45 cm, 29.78 cm] and the optimist growing water-depth of Carex lasiocarpa was 21.4 cm. The TWINSPAN, a polythetic and divisive classification tool, was used to classify the wetland ecological series into 6 associations. Result of TWINSPAN matrix classification reflected an obvious environmental gradient in these associations: water-depth gradient. The relation of biodiversity of Carex lasiocarpa community and water depth was determined by calculating the diversity index of each association

    Climate impacts of 2009/2010 mixed-type El Niño on double ITCZs over the eastern Pacific Ocean

    Get PDF
    A double intertropical convergence zone (ITCZ) pattern emerges over the eastern Pacific Ocean in March-April. Their inter-annual variabilities may exert major climatic and ecological effects. El Niño-Southern Oscillation (ENSO) can significantly regulate the inter-annual variability of double ITCZs. ENSO diversity has increased in recent years. A mixed-type El Niño occurred in 2009/2010. Our results reveal that the meridional SSTA pattern in mixed-type El Niño is a combination of “SST warming with a maximum at the equator” (i.e., EP-type delta SST) and “north-warm and south-cold” (i.e., CP-type delta SST) patterns. In a mixed-type El Niño, both meridional EP-type and CP-type delta SST played a role and had corresponding climate impacts. Under the coordinated modulation of EP-type and CP-type delta SST in a mixed-type El Niño, the climate effect of EP-type delta SST (increasing equatorial precipitation) is weakened; while the climate effect of CP-type delta SST (enhancing the northern ITCZ and weakening the southern ITCZ) is amplified. The climate effect of mixed-type El Niño finally resembles that of typical CP-type El Niños, intensifying the north-south asymmetry of the eastern Pacific double ITCZs. This study will contribute to a better understanding of the impacts of ENSO diversity on double ITCZs in the eastern Pacific region

    Cascade conversion of furfural to fuel bioadditive ethyl levulinate over bifunctional zirconium-based catalysts

    Get PDF
    Abstract(#br)Biomass-derived ethyl levulinate (EL) is currently deemed as a promising fuel bioadditive to improve (bio)diesel combustion performance without the sacrifice of its octane number. In this contribution, a range of Zr–Al bimetallic catalysts were prepared for the cascade conversion of furfural to EL by the integration of transfer hydrogenation and ethanolysis in ethanol. The ratio of Lewis to Brønsted acid sites (L/B) could be tuned by the ratio of Al 2 O 3 to ZrO 2 over SBA-15 support. Among these catalysts, Zr–Al/SBA-15(30:10) with appropriate L/B ratio of 2.25 exhibited an outstanding catalytic performance to give a furfural (FF) conversion up to 92.8% with a EL selectivity as high as 71.4% at 453 K in 3 h

    Non-targeted Metabolomic Study on Anti-aging Effect of Ripe Pu-erh Tea on D-Galactose-Induced Aging Mice

    Get PDF
    Delaying aging has become a hot spot of social concern and research. Our previous studies have shown that ripe Pu-erh tea can delay aging in mice by regulating the intestinal flora, but the metabolites in response to endogenous substances in mice are not clear. In this paper, the Morris water maze test was used to detect learning and memory capacity in control, D-galactose-induced aging, and ripe Pu-erh tea-treated mice. Non-targeted metabolomics was used to detect metabolites in the brain tissue and serum of mice from each group for the purpose of exploring the anti-aging effect of ripe Pu-erh tea on D-galactose-induced aging mice, screening differential metabolites among the three groups and analyzing the related metabolic pathways. The results showed that ripe Pu-erh tea improved learning capacity, and regulated 26 differential metabolites in the brain tissue of aging mice, mainly involved in the glycerophospholipid metabolism, vitamin B6 metabolism, histidine metabolism and purine metabolism pathways, among which the glycerophospholipid metabolism and histidine metabolism pathway were the most significant. A total of 11 differential metabolites were identified in serum, mainly involved in the metabolism of vitamin B6 and arachidonic acid, among which vitamin B6 metab olism pathway was the most significant. After the intervention with ripe Pu-erh tea, the contents of glycerophospholipid metabolites including phosphatidylcholine [PC (20:5/20:4)], phosphatidyl ethanlamine [PE (22:2/14:0)], phosphatidylserine [PS (20:5/18:1)] and lysophosphatidylcholine [LysoPC (18:2)], the histidine metabolite carnosine, and the vitamin B6 metabolite pyridoxal 5’-phosphate were significantly increased in aging mice. These results suggest that ripe Pu-erh tea can delay aging by regulating lipid and amino acid metabolism

    Physical Characterization and Volatile Organic Compound Monitoring of Recycled Polyethylene Terephthalate under Mechanical Recycling

    Get PDF
    In this study, physical characterization and monitoring of volatile organic compounds (VOCs) were investigated on recycled polyethylene terephthalate (rPET) from a mechanical recycling process and rPET bottles made with different rPET contents, with the aim of tracing the source of rPET and assessing its safety when use as a food contact material. It was found that rPET had a similar thermal stability to that of virgin PET (vPET). rPET bottles did not show any significant changes in groups or structure and exhibit similar crystallization and melting behaviors to vPET. However, there were minor mechanical scratches in the surface micromorphology of rPET bottles, and the color of rPET bottles became darker, greener and yellower as the content of recycled material increased. The solid-state polycondensation process was found to play an important role in the removal of VOCs, as detected by headspace gas chromatography-mass spectrometry (HS-GC-MS), resulting in a very small amount of residual VOCs in rPET. Four VOCs (acetaldehyde, glycol and nonanal at levels less than 1.00 mg/kg; 2-methyl-1,3 dioxolane at levels of 1.72-5.76 mg/kg) were detected in the rPET bottles. This study shows that rPET bottles are qualified for reuse in food contact in terms of thermal properties, structure, morphology and VOC residues, although there is variability in color

    Liver Damage Associated with Polygonum multiflorum

    Get PDF
    Objective. To summarize the characteristics and analysis of relevant factors and to give references for prevention and further study of liver damage associated with Polygonum multiflorum Thunb. (HSW), we provide a systematic review of case reports and case series about liver damage associated with HSW. Methods. An extensive search of 6 medical databases was performed up to June 2014. Case reports and case series involving liver damage associated with HSW were included. Results. This review covers a total of 450 cases in 76 articles. HSW types included raw and processed HSW decoction pieces and many Chinese patent medicines that contain HSW. Symptoms of liver damage occur mostly a month or so after taking the medicine, mainly including jaundice, fatigue, anorexia, and yellow or tawny urine. Of the 450 patients, two cases who received liver transplantation and seven who died, the remaining 441 cases recovered or had liver function improvement after discontinuing HSW products and conservative care. Conclusion. HSW causes liver toxicity and may cause liver damage in different degrees and even lead to death; most of them are much related to long-term and overdose of drugs. Liver damage associated with HSW is reversible, and, after active treatment, the majority can be cured. People should be alert to liver damage when taking HSW preparations

    Insights into the active sites and catalytic mechanism of oxidative esterification of 5-hydroxymethylfurfural by metal-organic frameworks-derived N-doped carbon

    Get PDF
    Abstract(#br)Directly oxidative esterification of Biomass-derived 5-hydroxymethylfurfural (HMF) into dimethyl furan dicarboxylate (DMFDCA) is a promising route for the replacement of petroleum-derived commodity chemical terephthalic acid (TPA) extensively employed in polyester synthesis. Co-based N-doped carbon materials are one of the most promising applied catalysts for oxidative esterification reaction, however, the active sites and reaction pathway of these catalysts have not been clearly clarified, which is crucial to the practical application. Herein, we report that ZIF-67 (a zeolitic imidazolate framework (ZIF)-type cobalt-containing MOF) derived Co@C-N material is a highly effective catalyst for the selective conversion of HMF into DMFDCA in 95% yield. The high activity of the ZIF-67 derived nanocarbon composites Co@C-N can be attributed to the electron transfer between nitrogen-doped carbon shells and Co nanoparticles. The appropriate graphitic N and pyridinic N doping increases the electronic mobility and active sites. Density functional theory (DFT) simulations indicated that oxygen, HMF and methanol molecules are adsorbed and activated on C-N materials. Furthermore, no 2, 5-diformylfuran (DFF) was captured as an intermediate because the oxidative esterification of aldehyde preferentially occurred than the oxidation of hydroxyl group in HMF. We anticipate that these results can drive progress in the bio-based polymers sector and oxidative esterification reaction

    Abnormal Topology of the Structural Connectome in the Limbic Cortico-Basal-Ganglia Circuit and Default-Mode Network Among Primary Insomnia Patients

    Get PDF
    Purpose: Primary insomnia (PI) is the second most common mental disorder. However, the topologic alterations in structural brain connectome in patients with PI remain largely unknown.Methods: A total of 44 PI patients and 46 age-, gender-, and education level matched healthy control (HC) participants were recruited in this study. Diffusion tensor imaging (DTI) and resting state MRI were used to construct structural connectome for each participant, and the network parameters were employed by non-parametric permutations to evaluate the significant differences between the two groups. Relationships between abnormal network metrics and clinical characteristics, including the disease duration, the Pittsburgh Sleep Quality Index (PSQI), the Insomnia Severity Index (ISI), the Self-Rating Anxiety Scale (SAS), and the Self-Rating Depression Scale (SDS), were investigated with Spearman’s correlation analysis in PI patients.Results: PI patients demonstrated small-world architecture with lower global (P = 0.005) and local (P = 0.035) efficiencies compared with the HC group. The unique hub nodal properties in PI patients were mainly in the right limbic cortico-basal-ganglia circuit. Five disrupted subnetworks in PI patients were observed in the limbic cortico-basal-ganglia circuit and left default-mode networks (DMN) (P < 0.05, NBS corrected). Moreover, most unique hub nodal properties in the right limbic cortico-basal-ganglia circuit were significantly correlated with disease duration, and clinical characteristics (SAS, SDS, ISI scores) in PI processing.Conclusion: These findings suggested the abnormal anatomical network architecture may be closely linked to clinical characteristics in PI. The study provided novel insights into the neural substrates underlying symptoms and neurophysiologic mechanisms of PI
    corecore