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Now showing items 1 - 16 of 24

  • Soil nitrogen leaching decreases as biogas slurry DOC/N ratio increases

    Jianbo Cheng   Yucheng Chen   Tengbing He   Renjun Liao   Renlu Liu   Man Yi   Lei Huang   Zhimin Yang   Tianling Fu   Xiangying Li  

    Highlights • Increasing DOC/N of biogas slurry to at least 7.3 reduced soil nitrogen leaching. • Slurry with DOC/N 7.3 enhanced soil denitrification. • Slurries with DOC/N 12.3 and 17.3 promoted N immobilization. • DOC/N 12.3 and 17.3 inhibited nitrifiers being promoted by DOC/N 0.9–7.3. • WGCNA identified the bacteria that may enhance or inhibit soil nitrification. Abstract Previous work has measured high rates of nitrogen (N) leaching during biogas slurry irrigation. Here we tested whether increasing the ratio of dissolved organic carbon (DOC) to N in biogas slurry would decrease N leaching by applying biogas slurries with DOC/N ratios of 0.9, 2.3, 7.3, 12.3 and 17.3 to soil columns in the laboratory. Increasing the DOC/N ratio to at least 7.3 reduced N leaching by approximately 91%, likely because denitrification and nitrate (NO 3 − ) consumption were increased in the DOC/N 7.3 treatment and ammonium immobilization increased (and NO 3 − production decreased) in the DOC/N 12.3 and 17.3 treatments. Additionally, all the detected soil nitrifiers—uncultured Nitrosomonadaceae, Nitrospira, Nitrosospira and Nitrosomonas— were promoted in the DOC/N 0.9–7.3 treatments and inhibited in the DOC/N 12.3 and 17.3 treatments. According to the results of weighted gene co-expression network analysis (WGCNA), it is likely that the soil nitrification was promoted by Acidobacteriaceae (Subgroup_1_uncultured), Rhizomicrobium , Massilia , uncultured Nitrosomonadaceae and Nitrospira but inhibited by Trichococcus .
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  • Vibrational spectroscopy and density functional theory study of ninhydrin

    Ran Li   Huimin Sui   Peipie Liu   Lei Chen   Jianbo Cheng   Bing Zhao  

    Graphical abstract Ninhydrin was designed as a model molecule for theoretical and experimental studies of the molecule structure. Fourier transform infrared (FTIR) and Raman spectra of the compound have been obtained experimentally. Most of the fundamentals vibrations agree well with the predicted frequencies. Highlights • Most of the fundamentals vibrations agree well with the predicted frequencies. • Hydrogen bond donors and acceptors are predicted. • The vibrational spectra of ninhydrin SERS are investigated experimentally and theoretically. Abstract In this paper, ninhydrin was designed as a model molecule for theoretical and experimental studies of the molecule structure. Density functional theory (DFT) calculations have been performed to predict the IR and Raman spectra for the molecule. In addition, Fourier transform infrared (FTIR) and Raman spectra of the compound have been obtained experimentally. Based on the modeling results obtained at the B3LYP/6-311++G** level, all FTIR and Raman bands of the compound obtained experimentally were assigned. Our calculated vibrational frequencies are in good agreement with the experimental values. The molecular electrostatic potential surface calculation was performed and the result suggested that the ninhydrin had two potential hydrogen bond donors and four potential hydrogen bond acceptors. HOMO–LUMO gap was also obtained theoretically at B3LYP/6-311++G** level.
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  • Gas-phase activation of methane with PtOH<sup>+</sup>

    Shaoli Liu   Jianbo Cheng   Qingzhong Li   Wenzuo Li  

    Graphical abstract Quasi-restricted orbital diagrams for the transition state after 3 PtHOH(CH 3 ) + . Highlights • The active reaction of methane by Pt(OH) + falls into three major categories. • The favorable path is the channel of the elimination of H 2 O. • The overall reaction is exothermic by 16.5 kcal/mol. • Pt(OH) + is more reactive than Pt + and [Pt(H)(OH)] + . Abstract Based on the density functional theory (DFT) level, the thermal reaction of PtOH + with methane has been investigated theoretically using the empirically parametrized hybrid functional B3LYP. The favorable path for the reaction of PtOH +  + CH 4 is the channel of the elimination of H 2 O. The overall reaction is exothermic by 16.5 kcal/mol. The NBO analysis demonstrated that the ligand effect resulting in the electronic occupies in the quasi-restricted orbitals and also shows a proton-coupled electron transfer component in 3 TS2-H 2 O. By comparing among the reactions of Pt + , [Pt(H)(OH)] + and PtOH + with CH 4 , PtOH + is more reactive to methane than Pt + and [Pt(H)(OH)] + thermodynamically. These results can not only deepen the understanding of the mechanism, but also guide the reasonable design of catalysts.
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  • Vibrational spectroscopy and density functional theory study of 4-mercaptobenzoic acid

    Ran Li   Haiming Lv   Xiaolei Zhang   Peipei Liu   Lei Chen   Jianbo Cheng   Bing Zhao  

    Graphical abstract 4-Mercaptobenzoic acid was designed as a model molecule for theoretical and experimental studies of the molecule structure. Fourier transform infrared (FTIR) and Raman spectra of the compound have been obtained experimentally. Most of the fundamentals vibrations agree well with the predicted frequencies. Highlights • Most of the fundamentals vibrations agree well with the predicted frequencies. • Hydrogen bond donors and acceptors are predicted. • The vibrational spectra of 4-MBA are studied experimentally and theoretically. Abstract In this paper, 4-mercaptobenzoic acid (4-MBA/pMBA) was designed as a model molecule for theoretical and experimental studies of the molecule structure. Density functional theory (DFT) calculations have been performed to predict the IR and Raman spectra for the molecule. In addition, Fourier transform infrared (FTIR) and Raman spectra of the compound have been obtained experimentally. Based on the modeling results obtained at the B3LYP/6-311++G ∗∗ level, all FTIR and Raman bands of the compound obtained experimentally were assigned. Our calculated vibrational frequencies are in good agreement with the experimental vales. The molecular electrostatic potential surface calculation was performed and the result suggested that the 4-MBA had two hydrogen bond donors and three hydrogen bond acceptors. HOMO–LUMO gap was also obtained theoretically at B3LYP/6-311++G ∗∗ level.
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  • Prediction and characterization of halogen bonds involving formamidine and its derivatives

    Xiulin An   Lixia Jiang   Qingzhong Li   Wenzuo Li   Jianbo Cheng  

    Graphical abstract Highlights • Formamidine (FA) is a good electron donor in halogen bonding. • The FA-( E ) complex is more stable than the FA-( Z ) counterpart. • The strong halogen bond has a nature of partially covalent interaction. • The strength of halogen bond can be regulated by substituents. Abstract Ab initio calculations have been carried out for the complexes of formamidine (FA) and some representative halogenated molecules XY (X = Cl, Br, and I; Y = F, CCH, CF 3 , CN, and NC). The FA-( Z ) complex combines with the halogenated molecule through a halogen bond, while the FA-( E ) complex is stabilized jointly by both a halogen bond and a X⋯H interaction. The FA-( E ) complex is more stable than the FA-( Z ) counterpart, with the interaction energy of −3.4 to −23.4 kcal/mol, indicating that FA is a good electron donor in halogen bonding. The methyl substituent particularly one at the imino nitrogen atom of FA has an enhancing effect on the strength of halogen bond. The similar effect is found for the phenyl and pyridyl substituents, depending on the FA conformation and substitution position of pyridyl. The stability of stronger halogen bonding is mainly attributed to electrostatic and polarization energies, which is different from the weak one with an electrostatic nature.
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  • 5-in. densely packed poly-crystal phosphor screen for HDTV projection CRT

    Gang Yang   Jianbo Cheng   Qionghua Wang   Wenbin Chen   Quan Jiang   Zulun Lin   Chunjing Zhao   Jun Wang   Hui Lin   Yourun Zhang   Qijun Ran  

    A novel 5-in. R.G.B densely packed poly-crystal MgAl 2O 4 (magnesium-aluminum-oxide) phosphor screens with multi-layer interface filter have been developed. The filter is a multi-layer alternate high and low index of refraction film which was fabricated by depositing high index of refraction of titanium oxide and low index of refraction of silicon oxide. The 5-in.R.G. B densely packed poly-crystal phosphor screens with the filter have 60% more luminance than those of common R.G. B poly-crystal phosphor screens, and the area of their chromaticity is almost 10% larger than that of common poly-crystal phosphor screen. The 5-in.R.G. B densely packed poly-crystal phosphor screens with multi-layer interface filter are fabricated by using a centrifugal sedimentation method. The resolution of densely packed poly-crystal phosphor screen with multi-layer interface filter is higher than that of conventional poly-crystal phosphor screen. An experimental 52-inch TV set adopting the set of 5-inch densely packed poly-crystal projection CRT with multi-layer interface filter has very high resolution of 2000 TV lines and 1800 cd/m 2 luminance, and it is easy to realize the HDTV display.
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  • A high-performance 5-in. polycrystal phosphor screen

    Gang Yang   Jianbo Cheng   Wenbin Chen   Qionghua Wang   Quan Jiang   Haibo Rao   Chunjing Zhao   Qijun Ran  

    We have ever reported a phosphor screen, which is a 5-in. poly-crystal MgAl 2O 4 phosphor screen. The 5-in. poly-crystal MgAl 2O 4 phosphor screen has a very good performance, such as high luminance, high resolution, cheap cost and easily obtained. Recently we develop a high performance 5-in. poly-crystal phosphor screen. We deposit a multi-layer interface filter on the poly-crystal MgAl 2O 4 substrate. The filter is a multi-layer alternate high and low index of refraction film which was fabricated by depositing high index of refraction of titanium oxide and low index of refraction of silicon oxide. The measurement results show that the filter not only increases the MgAl 2O 4 phosphor screen's white-D luminance, but also improves its chromaticity. The 5-in.R.G. B poly-crystal phosphor screens with the filter have 60% more luminance than those of common R.G. B poly-crystal phosphor screens, and the area of their chromaticity is almost 10% larger than that of common poly-crystal phosphor screen. The 5-in.R.G. B poly-crystal phosphor screens with the filter realize the authentic high performance
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  • Theoretical study of lithium bond between XMgH (X=H, F, CH 3) and LiCY 3 (Y=H, F)

    Jungang Yin   Peng Wei   Qingzhong Li   Zhenbo Liu   Wenzuo Li   Jianbo Cheng   Baoan Gong  

    Quantum chemical calculations have been performed to study lithium-bonded complexes of XMgH-LiCY 3 (X=H, F, CH 3; Y=H, F) at the MP2/6-311++G(d,p) level. The geometrical, spectral and energetic parameters have been analyzed. Upon complexation, the Mg-H and Li-C bonds are lengthened, whereas their stretch vibrations have a blue shift. The interaction energies are in a range of 9.71-15.97kcal/mol. The methyl group in CH 3MgH enhances this interaction, whereas that in LiCH 3 weakens it. The F atom in FMgH weakens this interaction, whereas that in LiCF 3 enhances it. The calculations of natural bond orbital (NBO) and atoms in molecules (AIM) have also been carried out for these complexes. The electrostatic interaction is mainly responsible for the stability of these lithium-bonded complexes. [All rights reserved Elsevier].
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  • Vibrational spectroscopy and density functional theory study on 1,4-bis[2-(4-pyridyl) ethenyl]-benzene

    Jianbo Cheng   Xiaoling Li   Wei Song   Weiqing Xu   Bing Zhao   Gang Zhang  

    Two single-bond conformational isomers (all- trans and trans-cis) of 1,4-bis[2-(4-pyridyl) ethenyl]-benzene (BPENB) have been studied using density functional theory (DFT) methods. The Fourier transform infrared (FTIR), Fourier transform Raman spectra (FT-Raman) and surface-enhanced Raman scattering (SERS) spectra of BPENB on new Ag substrates at different concentrations have been recorded. All FTIR, FT-Raman and SERS bands were assigned on the basis of the B3LYP/6-31++G(d,p) method. Our calculated vibrational frequencies are in good agreement with experimental wavenumbers. Surface selection rules derived from the electromagnetic enhancement model were employed to infer BPENB orientations on a silver substrate surface at different concentrations. [All rights reserved Elsevier]
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  • Tetrel bonds between PySiX3 and some nitrogenated bases: Hybridization, substitution, and cooperativity

    Mingxiu Liu   Qingzhong Li   Wenzuo Li   Jianbo Cheng  

    Graphical abstract Highlights • PySiX 3 forms a tetrel bond with some nitrogenated bases. • The strength of tetrel bond is affected by the substitution and hybridization effects. • The tetrel bond is mainly governed by electrostatic and polarization interactions. • The tetrel bond exhibits cooperative effects with triel bond. Abstract Ab initio calculations have been performed to study the influence of hybridization, substitution, and cooperativity on the tetrel bond in the complexes of PySiX 3 (Py = pyridine and X = halogen). The tetrel bond becomes stronger in the order of p -PySiF 3 ⋯NCH( sp ) < p -PySiF 3 ⋯NHCH 2 ( sp 2 ) < p -PySiF 3 ⋯NH 3 ( sp 3 ). The electron-donating group in the electron donor strengthens the tetrel bond, and this effect is mainly achieved through electrostatic and polarization interactions. Tetrel bonding displays cooperative effects with triel bonding and chalcogen bonding, characterized by shorter binding distances and greater electron densities. The cooperative effects between triel/chalcogen bond and tetrel bond have been analyzed by molecular electrostatic potentials and charge transfer. Energy decomposition indicates that many-body effects are mainly caused by polarization energy. The geometries of Si⋯N interaction and its applications in crystal materials have been characterized and evidenced by a CSD research.
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  • Photophysical properties and excited state proton transfer in 1,8-Dihydroxydibenzo[a,h]phenazine: A theoretical study

    Bo Xiao   Xue-fang Yu   Qingzhong Li   Jianbo Cheng  

    Graphical abstract Highlights • Photophysical properties and excited state proton transfer were studied. • Double proton transfer process occurs following stepwise mechanism. • Inter-system crossing between S 1 and T 2 and T 3 is responsible for the fluorescence quenching. • Internal conversion from S 1 to S 0 dose not contribute to the fluorescence quenching. Abstract The photophysical properties as well as proton transfer process from normal form (Enol) to tautomer form (Keto) in 1,8-Dihydroxydibenzo[a,h]phenazine [DHBP] have been theoretically investigated by TDDFT method. The potential energy profiles of the reaction paths for concerted proton transfer and stepwise proton transfer via single-proton transferred intermediate (INT) are examined, and the results show that proton transfer occurs in locally excited state following the stepwise mechanism at the lowest excitation energy in the gas phase. The concerted reaction path is found to be unstable with respect to anti-symmetric mode statically. The steady state emission band detected in Piechowska et al. experiment was assigned to INT, while emissions from Enol and Keto are less likely to be observed. The low intensity of the fluorescence at INT can be explained by the inter-system crossing between the lowest singlet state S 1 with the triplet states T 1 and T 2 instead of the internal conversion from S 1 to S 0 introduced by torsion at INT structure at current computational level. This study provides new insight into the quenching mechanism in π-extended rigid molecule DHBP.
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  • Data from identification of diagnostic biomarkers and metabolic pathway shifts of heat-stressed lactating dairy cows

    He Tian   Weiyu Wang   Nan Zheng   Jianbo Cheng   Songli Li   Yangdong Zhang   Jiaqi Wang  

    Abstract Controlling heat stress (HS) is a global challenge for the dairy industry. In this work, an integrated metabolomics and lipidomics approach using 1 H nuclear magnetic resonance (NMR) and ultra-fast LC–MS in combination with multivariate analyses was employed to investigate the discrimination of plasma metabolic profiles between HS-free and HS lactating dairy cows. Here we provide the information about the acquiring and processing of raw data obtained by 1 H NMR and LC–MS techniques. The data of present study are related to the research article “Identification of diagnostic biomarkers and metabolic pathway shifts of heat-stressed lactating dairy cows” in the Journal of Proteomics ( Tian et al., J. Proteomics, (2015), doi:10.1016/j.jprot.2015.04.014 ).
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  • Effects of dietary copper source and level on metabolic hormones and lipogenic and lipolytic enzyme activities in lambs

    Jianbo Cheng   Caiyun Fan   Wei Zhang   Xiaogang Yan   Lisheng Wang   Zhihai Jia   Xiaoping Zhu  

    This experiment was conducted to determine the effect of dietary copper (Cu) on metabolic hormones and activities of lipogenic and lipolytic enzymes in lambs. Fifty Dorper x Mongolia wether lambs (approximately 3 month of age; average BW = 23.8 +/- 0.6 kg) were randomly assigned to one of five treatments. Treatments consisted of (1) control (no supplemental Cu), (2) 10 mg Cu/kg DM from Cu-lysine, (3) 20 mg Cu/kg DM from Cu-lysine, (4) 10 mg Cu/kg DM from tribasic copper chloride (Cu-2(OH)(3)Cl; TBCC), and (5) 20 mg Cu/kg DM from TBCC. The Cu concentration was 6.74 mg/kg DM in the basal diet. Blood samples were collected on days 0, 30, and 60, and then the lambs were slaughtered on day 60. Plasma insulin concentration was decreased (P<0.05) by Cu supplementation on days 30 and 60. Plasma leptin concentration was not affected on day 30, but was increased (P<0.05) on day 60 in lambs supplemented with Cu compared with the controls. The activities of fatty acid synthase (FAS), NADP-malate dehydrogenase (MD), and glucose-6-phosphate dehydrogenase (G6PDH) were decreased (P<0.05) in subcutaneous (SC) adipose and liver tissues by Cu supplementation. Lipoprotein lipase (LPL) activity was decreased by Cu supplementation (P<0.05) in SC adipose tissue, but was not affected (P>0.05) in liver tissue. Hormone-sensitive lipase (HSL) activity was increased (P<0.05) in SC adipose and liver tissues by Cu supplementation. There were no differences between supplemental Cu form or level in metabolic hormone levels or activities of FAS, MD, G6PDH, LPL, or HSL. These results indicate that Cu supplementation altered plasma insulin and leptin metabolism, decreased lipogenic enzyme activities, and increased lipolytic enzyme activities in SC adipose and liver tissues in lambs. The reduction in backfat depth of lambs may be due to effects of Cu in reducing synthesis of adipose tissue and increasing lipolysis. (C) 2009 Elsevier B.V. All rights reserved.
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  • Effects of Different Copper Sources and Levels on Plasma Superoxide Dismutase, Lipid Peroxidation, and Copper Status of Lambs

    Jianbo Cheng   Hui Ma   Caiyun Fan   Zijun Zhang   Zhihai Jia   Xiaoping Zhu   Lisheng Wang  

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  • A two-gene ABC-type transport system that extrudes Na+ in Bacillus subtilis is induced by ethanol or protonophore

    Jianbo Cheng   Arthur A. Guffanti   Terry Ann Krulwich  

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  • Feeding rumen-protected gamma-aminobutyric acid enhances the immune response and antioxidant status of heat-stressed lactating dairy cows

    Jianbo Cheng   Nan Zheng   Xianzhi Sun   Songli Li   Jiaqi Wang   Yangdong Zhang  

    Abstract This experiment was conducted to investigate the effects of rumen-protected gamma-aminobutyric acid (GABA) on immune function and antioxidant status in heat-stressed dairy cows. Sixty Holstein dairy cows were randomly assigned to 1 of 4 treatments according to a completely randomized block design. The treatments consisted of 0 (control), 40, 80, or 120 mg of GABA/kg DM from rumen-protected GABA. The trial lasted 10 weeks. The average temperature-humidity indices at 0700, 1400 and 2200 h were 78.4, 80.2 and 78.7, respectively. Rectal temperatures decreased linearly at 0700, 1400, and 2200 h with increasing GABA. As the GABA increased, the immunoglobulin (Ig) A and IgG contents and the proportions of CD4 + and CD8 + T lymphocytes increased linearly ( P <0.05), whereas concentrations of interleukin (IL)-2, IL-4, IL-6 and tumor necrosis factor-α (TNF-α) decreased linearly ( P <0.05). The activities of superoxide dismutase (SOD), glutathione-peroxidase (GSH-PX) and total antioxidant capacity (T-AOC) increased linearly ( P <0.05), whereas malondialdehyde (MDA) content decreased linearly ( P <0.05) with increasing GABA. These results indicate that rumen-protected GABA supplementation to heat-stressed dairy cows can improve their immune function and antioxidant activity. Highlights • We develop a new strategy that can help maintain heat-stressed dairy cows' health. • Gamma-aminobutyric acid (GABA) was supplemented to heat-stressed dairy cows. • Rumen-protected GABA can improve immune function in heat-stressed dairy cows. • Rumen-protected GABA can improve antioxidant activity in heat-stressed dairy cows.
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