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1.
Effects of a cold atmospheric pressure plasma (CAPP) treatment on the germination, production of biomass, vigor of seedlings, uptake of water of wheat seeds (Triticum aestivum L. cv. Eva) were investigated. The CAPP treatment influence on the inactivation of microorganisms occurring on the surface of wheat seeds was investigated also. The so-called Diffuse Coplanar Surface Barrier Discharge generating a cold plasma in ambient air with high power volume density of some 100 W/cm3 was used for the treatment of seeds at exposure times in the range of 10–600 s. The optical emission spectroscopy and the electrical measurements were used for estimation of CAPP parameters. The obtained results indicate that the germination rate, dry weight and vigor of seedlings significantly increased for plasma treatment from 20 to 50 s. The plasma treatment of seeds led to an extensive increase in wettability and faster germination comparing with the untreated seeds. The growth inhibition effect of CAPP on the surface microflora of wheat seeds increased with the increase of the treatment time. The efficiency of the treatment of wheat seeds artificially contaminated with pure cultures of filamentous fungi decreased in the following order: Fusarium nivale > F. culmorum > Trichothecium roseum > Aspergillus flavus > A. clavatus.  相似文献   

2.
The reaction on 8-hydroxy quinoline-7-aldehyde azo compounds (HL n ) (where n = 1–5) with 4-amino-1,2-dihydro-2,3-dimethyl-1-phenylpyrazol-5-one to obtain HL n (where n = 6–10) have been characterized by means of TLC, melting point and spectral data, such as IR, 1H NMR, mass spectra and thermal studies. The X-ray diffraction patterns of two starting materials 8-hydroxy quinoline-7-aldehyde (start 1), 4-amino-1,2-dihydro-2,3-dimethyl-1-phenylpyrazol-5-one (start 2) and the ligands (HL5,10) are investigated in powder form. All the ligands have been screened for their antimicrobial activity against four local bacterial species, two Gram-positive bacteria (Bacillus cereus and Staphylococcus aureus) and two Gram-negative bacteria (Escherichia coli and Klebsiella pneumoniae) as well as against four local fungi; Aspergillus niger, Alternaria alternata, Penicillium italicum and Fusarium oxysporium. The results show that the azo ligands (HL n ) (where n = 1–5) have no antimicrobial activity against bacteria and fungi while most azomethine ligands (HL n ) (where n = 6–10) are good antibacterial agents against E. coli and K. pneumoniae as well as antifungal agents against P. italicum and A. alternata. The results were compared to standard substances (start 1) and (start 2). Among the azomethine ligands, HL10 was the most effective against the most microorganisms tested. The size of clear zone was ordered as p-(OCH3 < CH3 < H < Cl < NO2) as expected from Hammett’s constant (σ R ). Also, the ultrastructure study of the affected bacteria confirmed that HL8 is good antibacterial agent against E. coli and S. aureus.  相似文献   

3.
Medium pressure (~ 10 torr) low frequency (3–5 kHz) glow discharge (LFGD) plasmas were applied to treat wheat (Triticum aestivum) seeds to investigate the effects on water absorption, seed germination rate, seedling growth and yield. The LFGD plasmas were produced with air and air/O 2. Optical emission spectroscopic diagnostic methods were revealed that the \({\text{N}}_{2} \left( {{\text{C}}^{3}\Pi _{\text{u}} - {\text{B}}^{3}\Pi _{\text{g}} } \right)\), \({\text{N}}_{2}^{ + } \left( {{\text{B}}^{2}\Sigma _{\text{u}}^{ + } - {\text{X}}^{2}\Sigma _{\text{g}}^{ + } } \right)\) and \({\text{N}}_{2} \left( {{\text{B}}^{3}\Pi _{\text{g}} - {\text{A}}^{3}\Sigma _{\text{u}}^{ + } } \right)\) produced with air, and O species were produced along with nitrogen species with air/O 2 plasmas, respectively. The SEM images were revealed that the surface architectures and functionalities of the seeds were modified due to plasma treatments. Water absorption was found to increase with treatment time. 6 min treatment was provided 95–100% seed germination. The plants grown from treated seeds for 3 and 9 min duration by air/O 2 plasma were showed the highest growth activity and dry matter accumulation. Total chlorophyll contents of the leaves, longest spikes and number of spikes/spikelet were also increased. The wheat yield was increased ~ 20% over control by 6 min treatment with air/O 2 plasma. Overall results revealed that LFGD plasmas can significantly change seed surface architecture, water absorption, germination rate, seedling growth and yield of wheat.  相似文献   

4.
The aim of our study was to investigate the potential association of mRNA expression and plasma levels of the LIM domain 7 (LMO7) gene with the pathogenesis of dilated cardiomyopathy (DCM). Two SNPs of the LMO7 gene were genotyped in 310 patients with DCM and 415 controls. Our results showed that SNP rs7986131 (p = 0.002, OR = 1.38, 95% CI = 1.12–1.71), but not SNP rs4884021, was associated with DCM in the Han Chinese population. Haplotype analysis showed that the haplotype GT was associated with increased DCM susceptibility while AC was a protective haplotype. The Cox multivariate survival analysis indicated that the rs7986131 TT genotype (HR 1.659, 95% CI = 1.122–2.454, p = 0.011) was an independent multivariate predictor for shorter overall survival in patients with DCM. LMO7 mRNA expression and plasma LMO7 levels were significantly decreased in DCM (p < 0.0001). Spearman correlation test revealed that the plasma LMO7 level was negatively associated with left ventricular end-diastolic diameter (r = ?0.384, p = 0.01), left ventricular end-diastolic volume (r = ?0.375, p = 0.012), and brain natriuretic peptide (r = ?0.482, p = 0.001). Our study suggested that the LMO7 gene may play an important role in the pathogenesis of DCM in the Han Chinese population.  相似文献   

5.
Although log P is now recognized to be a key factor that determines the bioactivity of a molecule, the focus of medicinal chemists on hydrophobicity and log P started with the quantitative structure–activity relationships (QSAR) publications of Hansch and Fujita. Their original publication represents a dramatic change of focus to incorporate consideration of log P after a decade of work unsuccessfully attempting to use the Hammett equation to explain the structure-activity relationships of plant growth regulators. QSAR allows one to explore the quantitative relationship between log P and biological activity even when other factors also influence potency. In particular, Hansch’s publications of thousands of QSAR equations demonstrate that a relationship of biological activity with log P is indeed a general phenomenon. Hansch’s group also provided data and tools that enable others to explore the relationship between log P and the biological activity of compounds of interest.  相似文献   

6.
The isolated polystyrene chains spin-labeled with peroxide radical at the free end (IPSOO) in which the chain roots were covalently bonded to the surface of microcrystalline cellulose (MCC) powder were produced by mechanochemical polymerization of styrene initiated by MCC mechanoradicals. The IPSOO was used as motional probes at the ends of isolated polystyrene chains tethered on the surface of MCC powder. Two modes for the molecular motion of IPSOO were observed. One was a tumbling motion of IPSOO on the MCC surface, defined as a train state, and another was a free rotational motion of IPSOO protruding out from the MCC surface, defined as a tail state. The temperature of tumbling motion (T tum ) of IPSOO at the train state was at 90 K with anisotropic correlation times. T tum (90 K) is extremely low compared to the glass transition temperature (T g b ; 373 K) of polystyrene in the bulk. At temperatures above 219 K, the IPSOO was protruded out from the MCC surface, and freely rotated at the tail state. The train–tail transition temperature (T traintail ) was estimated to be 222 K. T tum (90 K) and T traintail (222 K) are due to the extremely low chain segmental density of IPSOO on the MCC surface under vacuum. The interaction between IPSOO and the MCC surface is a minor contributing factor in the mobility of IPSOO on the surface under vacuum. It was found that peroxy radicals are useful probes to characterize the chain mobility reflecting their environmental conditions.  相似文献   

7.
The expansion of an oxygen low-pressure microwave plasma was investigated in order to determine the optimal plasma parameters for the growth of functional oxide semiconductors. Langmuir probe measurements show that the electron density (n e ) increases with the injected power up to a saturation value of 3.0 × 109 cm?3 determined at 10 mTorr while electron temperature (T e ) remains constant at a value of 1.5 eV. When pressure is varied, n e shows a maximum value at a range from 12 to 20 mTorr while T e decreases monotonously with increasing pressure. In addition, both n e and T e decrease with the axial distance from the plasma source. These effects were discussed through the loss mechanisms in the remote plasma. For a pressure of 13 mTorr and at a substrate temperature of 500 °C, plasma enhanced oxidation of pure metallic Ti thin films lead to the formation of a pure TiO2 anatase phase compared to a mixed phase of TiO2 and TiO in the absence of plasma activation. For Mn thin films, the exposure to oxygen remote plasma led to the formation of MnO2 as opposed to obtaining Mn3O4 when oxidation is performed in the oxygen gas ambient. Remote plasma processing was thus found to provide selective pathways to control oxidation states, stoichiometry and phase composition of technologically attractive oxide thin films.  相似文献   

8.
For the first time in the published literature, a study is described concerning the use of the saw-sedge Cladium mariscus (C. mariscus) for adsorption of 2,4-dichlorophenoxyacetic acid (2,4-D) from aqueous systems. Among the experiments carried out, the elemental composition of C. mariscus was determined (C = 48.0 %, H = 7.1 %, N = 0.95 %, S = 0.4 %), FTIR spectroscopic analysis was performed to confirm the chemical structure of the adsorbent, and porous structure parameters were measured: BET surface area (A BET  = 0.6 m2/g), total pore volume (V p  = 0.001 cm3/g) and average pore size (S p  = 6.6 nm). It was shown that the effectiveness of removal of 2,4-D from aqueous systems using C. mariscus depends on parameters of the process: contact time, system pH, mass of sorbent, and temperature. Maximum adsorption was attained for a solution at pH = 3. Further increase in the alkalinity of the tested systems led to a reduction in the effectiveness of the process. The kinetic of adsorption of 2,4-D by C. mariscus was also determined, and thermodynamic aspects were investigated. The experimental data obtained correspond to a pseudo-second-order kinetic model of type 1. Additionally the negative values obtained for ΔHº indicate that the process is exothermic, and the negative values of ΔGº show it to be spontaneous. As the temperature of the system increases the spontaneity of adsorption is reduced, in accordance with the exothermic nature of the process.  相似文献   

9.
With the Gibbs free energy method, we determine the molar fraction in a plasma at and out of thermal equilibrium consisting of air and aluminum for several percentages in the temperature range of 500–6000 K. We take three temperatures into account (T rot  = T h ; T vib ; T ex  = T e ). We indicate the formulae and the numerical method used to perform the calculation taking three condensed phases AlN, Al, Al2O3 into account. We show that the air percentage plays a major role to create these phases. We clarify the role plays on the vaporization temperatures and on the sublimation temperature by the non-thermal equilibrium of the plasma. This kind of plasma is found in arc roots, near a wall, in plasmas with a high value of electrical field,… The influence of the pressures until 30 × 105 Pa. is shown on molar fraction of the chemical species, on the vaporization temperatures and on the sublimation temperature. The vaporization temperatures are given versus the thermal non equilibrium versus various mixtures (air, aluminum) and versus the pressures (105 Pa–30 × 105 Pa).  相似文献   

10.
LRM (Low Rank Modification) is a mathematical method that produces eigenvalues and eigenstates of generalized eigenvalue equations. It is similar to the perturbation expansion in that it assumes the knowledge of the eigenvalues and eigenstates of some related (unperturbed) system. However, unlike perturbation expansion, LRM produces correct results however large the modification of the original system. LRM of finite-dimensional systems is here generalized to the combined (external and internal) modifications. Parent n-dimensional system A n containing n eigenvalues λ i and n eigenstates \({| {\Phi_i}\rangle}\) is described by the generalized n × n eigenvalue equation. In an external modification system A n interacts with another ρ-dimensional system B ρ which is situated outside the system A n . In an internal modification relatively small σ-dimensional subsystem of the parent system A n is modified. Modified system C n+ρ that contains external as well as internal modifications is described by the generalized (n + ρ) × (n + ρ) eigenvalue equation. This system has (n + ρ) eigenvalues \({\varepsilon_s}\) and (n + ρ) corresponding eigenstates \({| {\Psi_s}\rangle}\) . In LRM this generalized (ρn) × (ρn) eigenvalue equation is replaced with a (nonlinear) (ρ + σ) × (ρ + σ) equation which produces all eigenvalues \({\varepsilon_s \notin \left\{ {\lambda_i}\right\}}\) and all the corresponding eigenstates \({| {\Psi_s}\rangle }\) of C n + ρ. Another equation produces remaining solutions (if any) that satisfy \({\varepsilon_s \in \left\{ {\lambda_i}\right\}}\) . Those two equations produce exact solution of the modified system C n + ρ. If (ρσ) is small with respect to n, this approach is numerically much more efficient than a standard diagonalization of the original generalized eigenvalue equation. Unlike perturbation expansion, LRM produces exact results, however large modification of the parent system A n .  相似文献   

11.
Power characteristics for an agitated vessel equipped with planar short baffles of length L and pitched blade turbine of pitch β are presented in the paper. The studies were carried out in the vessel of inner diameter D = 0.6 m, where the baffles were located in the distance p from the vessel bottom (p + L = H). Torque was measured using strain gauge method within the turbulent regime of the flow of Newtonian liquid in the agitated vessel. The effects of the pitch β and geometrical parameter p/H on the power number Ne were determined mathematically. The results showed that, for the assumed value of the angle β, the function Ne = f (L/H) decreases with the decrease in the baffle length L (i.e. with the increase in the parameter p). Moreover, for the assumed value of the baffle length L, the function Ne = f (β) increases with the increase in the angle β of the inclination of the impeller blade.  相似文献   

12.
In the present study, cellulose-lignin beads were prepared using pretreated dissolving grade-pulp and extracted from birch wood hydrotropic lignin as starting materials. The preparation involved dissolution of both polymers in environmentally friendly 7% NaOH/12% urea aqueous solution, shaping the solution into beads and subsequent regeneration. Lignin content in the beads varied from 0 to 40%. The beads were characterized using FTIR, scanning electron and confocal fluorescence microscopy. Porosity, swelling behavior and leaching of lignin from the beads in water were studied as well. The antibacterial properties of the beads and original hydrotropic lignin were tested using Escherichia coli (XL-1 Blue) and Staphylococcus aureus (ATCC 25923). The obtained beads in a never-dried state were highly porous spherical particles with evenly distributed lignin in them. Their shape, structure and properties were influenced by the lignin content. The beads did not show antibacterial activity against gram-negative E. coli. On the other hand, never-dried cellulose-lignin beads inhibited growth of gram-positive S. aureus, and the inhibition efficiency increased with the lignin content. The half inhibitory concentration for never-dried beads with 40% of lignin was 1.06 mg (dry weight) per 1 mL of broth determined after incubation for 24 h at 37 °C and at initial concentration of S. aureus of 6.48 log(CFU/mL). In contrast to cellulose-lignin beads, pure cellulose beads did not inhibit growth of S aureus. The results demonstrated that hydrotropic birch lignin can be used for the preparation of composite cellulose-lignin beads. Such beads show a great potential for antibacterial applications against S. aureus.  相似文献   

13.
Two thiosemicarbazones, (E)-2-(2,4-dimethoxybenzylidene)thiosemicarbazone (24-MBTSC (1)) and (E)-2-(2,5-dimethoxybenzylidene)thiosemicarbazone (25-MBTSC (2)), derived from 2,4-dimethoxybenzaldehyde and 2,5-dimethoxybenzaldehyde, respectively, with thiosemicarbazide have been synthesized and their structures were characterized by elemental analyses, FT-IR, 1H NMR spectroscopy, and X-ray single-crystal diffraction analysis. Molecular orbital calculations have been carried out for 1 and 2 by using an ab initio method (HF) and also density functional method (B3LYP) at 6-31G basis set. Compound 1 crystallizes in the monoclinic system, space group P21/c, with a = 8.1342(5) Å, b = 18.1406(10) Å, c = 8.2847(6) Å, β = 109.7258(17)°, V = 1150.75(12) Å3, and Z = 4, whereas compound 2 crystallizes in the orthorhombic system, space group Pbca, with a = 11.0868(6) Å, b = 13.1332(6) Å, c = 15.9006(8) Å, V = 2315.2(2) Å3, and Z = 8. The compounds 1 and 2 displays a trans-configuration about the C=N double bond.  相似文献   

14.
Guanidine dichloroacetate was synthesized and separated as crystals. Differential scanning calorimetry (DSC) measurement shows that this compound undergoes a reversible phase transition at about 275 K with a heat hysteresis of 28 K. Step-like dielectric anomaly observed at 274 K further confirms the phase transition. The single-crystal X-ray diffraction data suggested that these was a transition from a room-temperature phase with the space group of P21/n (a = 8.030(5), b = 12.014(9), c = 8.124(6) Å, β = 96.089(1)°, V = 779.3(1) Å3, and Z = 4) to a low-temperature one with the space group of P21/c (a = 7.941(2), b = 11.828(3), c = 10.614(2) Å, β = 130.985(1)°, V = 752.6(3) Å3, and Z = 4). The displacements of hydrogen bonds induce the structure phase transition.  相似文献   

15.
Saccharomyces cerevisiae PTCC5269 growth was evaluated to specify an optimum culture medium to reach the highest protein production. Experiment design was conducted using a fraction of the full factorial methodology, and signal to noise ratio was used for results analysis. Maximum cell of 8.84 log (CFU/mL) was resulted using optimized culture composed of 0.3, 0.15, 1, and 50 g L?1 of ammonium sulfate, iron sulfate, glycine, and glucose, respectively at 300 rpm and 35 °C. Glycine concentration (39.32 % contribution) and glucose concentration (36.15 % contribution) were determined as the most effective factors on the biomass production, while Saccharomyces cerevisiae growth had showed the least dependence on ammonium sulfate (5.2 % contribution) and iron sulfate (19.28 % contribution). The most interaction was diagnosed between ammonium sulfate and iron sulfate concentrations with interaction severity index of 50.71 %, while the less one recorded for glycine and glucose concentration was equal to 8.12 %. An acceptable consistency of 84.26 % was obtained between optimum theoretical cell numbers determined by software of 8.91 log (CFU/mL), and experimentally measured one at optimal condition confirms the suitability of the applied method. High protein content of 44.6 % using optimum culture suggests that Saccharomyces cerevisiae is a good commercial case for single cell protein production.  相似文献   

16.
S-allyl-β-N-[(2-hydroxyphenyl)methylene]hyrazinecarbodithioate) (1, H2L), the Schiff base of dithiocarbazate with unsaturated allyl substitution, can act as a new tridentate SNO ligand H2–L and react with cobalt(II) nitrate hexahydrate to form the novel linear trinuclear isovalence Co(II) complex, [Co3(H–L)2(L)2] 2C2H5OH (2). The compounds were characterized by elemental analysis, infrared, and ultraviolet spectroscopy. Compound 2 was also characterized by single-crystal X-ray analysis and crystallizes in the orthorhombic space group, Pbcn, with a = 30.643(1) Å, b = 9.118(4) Å, c = 19.017(7) Å, α = β γ = 90°, V = 5312.95 Å3, Z = 4, and R 1 = 0.0790, (wR 2) = 0.1223. The six-coordinate central Co(II) atom is bonded to two deprotonated metal-containing ligands. The terminal Co(II) atoms are in a square planar SNON four-coordinate environment and connected to the central Co(II) by N-atoms from the ligand backbone. For quantifying the intermolecular interactions in crystal lattice, the new d norm surface and the breakdown of fingerprint plots have been used for visualizing and exploring the compound 2.  相似文献   

17.
A novel bis-heterocyclic compound was synthesized and characterized. The crystal structure of the title compound (C22H20ClN5OS, Mr = 437.94) has been determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group P-1 with a = 8.646 (2), b = 9.148 (3), c = 14.540 (4) Å, α = 94.422 (4), β = 98.500 (4), γ = 102.823 (4)°, V = 1101.8 (5) Å3, Z = 2, F(000) = 312, Dc = 1.320 g/cm3, μ = 0.2900 mm?1, the final R 1 = 0.041000 and wR 2 = 0.1160 for 2675 observed reflections with I > 2σ(I). A total of 5623 reflections were collected, of which 3866 were independent (R int = 0.019000). The fungicidal activity of title compound was determined, the results showed the title compound displayed moderate fungicidal activity against G. zeae Petch, Phytophthora infestans (Mont.) de Bary, Botryosphaeria berengeriana f. sp. piricola (Nose) koganezawa et Sakuma, Fusarium oxysporum f.sp. cucumerinum, and Cercospora arachidicola.  相似文献   

18.
Tetracosactide (Synacthen), a synthetic analogue of adrenocorticotropic hormone (ACTH), can be used as a doping agent to increase the secretion of glucocorticoids by adrenal glands. The only published method for anti-doping control of this drug in plasma relies on purification by immunoaffinity chromatography and LC/MS/MS analysis. Its limit of detection is 300 pg/mL, which corresponds to the peak value observed 12 h after 1 mg Synacthen IM administration. We report here a more sensitive method based on preparation of plasma by cation exchange chromatography and solid-phase extraction and analysis by LC/MS/MS with positive-mode electrospray ionization using 7–38 ACTH as internal standard. Identification of Synacthen was performed using two product ions, m/z 671.5 and m/z 223.0, from the parent [M?+?5H]5+ ion, m/z 587.4. The recovery was estimated at 70%. A linear calibration curve was obtained from 25 to 600 pg/mL (R 2?>?0.99). The lower limit of detection was 8 pg/mL (S/N?>?3). The lower limit of quantification was 15 pg/mL (S/N?>?10; CV%?相似文献   

19.
A novel cyclopropane derivative, 1-cyano-N-p-tolylcyclopropanecarboxamide (C12H12N2O, Mr = 200.24) was synthesized and its structure was studied by X-ray diffraction, FTIR, 1H and 13C NMR spectrum and MS. The crystals are monoclinic, space group P2_1/c with a = 7.109 (4), b = 13.758 (7), c = 11.505 (6) Å, α = 90.00, β = 102.731 (8), γ = 90.00 °, V = 1097.6 (9) Å3, Z = 4, F(000) = 312, D c  = 1.212 g/cm3, μ = 0.0800 mm?1, the final R = 0.0490 and wR = 0.1480 for 1,375 observed reflections with I > 2σ(I). A total of 6,109 reflections were collected, of which 2,290 were independent (R int = 0.0290). Theoretical calculation of the title compound was carried out with HF/6-31G (d,p), B3LYP/6-31G (d,p), MP2/6-31G (d,p). The full geometry optimization was carried out using 6-31G(d,p) basis set, and the frontier orbital energy. Atomic net charges were discussed, and the structure-activity relationship was also studied. The preliminary biological test showed that the synthesized compound is bioactive against the KARI of Escherichia coli.  相似文献   

20.
The crystal structures of four organoselenium compounds, viz. bis(2-formylphenyl)diselenide (5), bis(2-methylnaphthyl)diselenide (6), organoselenenyl sulfide (7), and spiroselenurane (8) are described. Crystal data for 5: space group Pca21, crystal system orthorhombic, a=7.9969(4) Å, b=20.8794(12) Å, c=15.8307(13) Å, Z=8, R=0.0292. Owing to the presence of a strong Se···O interaction in compound 5 the geometry around the selenium atom may be considered as T-shaped. Crystal data for 6: space group Pna21, crystal system orthorhombic, a=18.2253(12) Å, b=13.0714(8) Å, c=7.7355(5) Å, Z=4, R=0.0570. The molecule has a cisoid conformation. Crystal data for 7: space group Pbcn, crystal system orthorhombic, a=22.2144(13) Å, b=8.0255(4) Å, c=15.4496(9) Å, Z=8, R=0.0292. Due to intramolecular Se···N interaction in 7 the geometry around selenium is T- shaped. Crystal data for 8: space group P21/c, crystal system monoclinic, a=7.4585(5) Å, b=19.5634(13) Å, c=8.0428(5) Å, β=97.1320(10)°, Z=4, R=0.0254. The O?Se?O angle is 172.86(6)°.  相似文献   

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