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Accumulation of heavy metals (HMs) by ornamental plants (OPs) from contaminated agriculture soils is a unique technique that can efficiently reduce the metal load in the food chain. Amaranthus tricolor L. has attractive characteristics acquiring a higher growth rate and large biomass when grown at heavy metal contaminated soils. Site-specific detailed information is not available on the use of A. tricolor plant in metal phytoremediation from the polluted sites. The study aimed to enhance the uptake of HMs (Pb, Zn, and Cu) via amending poultry litter extract (PLE), vinasse sugarcane (VSC), and humic acid (HA) as natural mobilized organic materials compared to ethylene diamine tetraacetic acid (EDTA), as a common mobilized chemical agent by A. tricolor plant. The studied soils collected from Helwan, El-Gabal El-Asfar (Cairo Governorate), Arab El-Madabeg (Assiut Governorate), Egypt, and study have been conducted under pot condition. Our results revealed all organic materials in all studied soils, except EDTA in EL-Gabal El-Asfar soil, significantly increased the dry weight of the A. tricolor plant compared to the control treatment. The uptake of Pb and Zn significantly (p > 0.05) increased due to applying all organic materials to the studied soils. HA application caused the highest uptake as shown in Pb concentration by more than 5 times in Helwan soil and EDTA by 65% in El-Gabal El-Asfar soil while VSC increased it by 110% in El-Madabeg soil. Also, an increase in Zn concentration due to EDTA application was 58, 42, and 56% for Helwan, El-Gabal El-Asfar, and El-Madabeg soil, respectively. In all studied soils, the application of organic materials increased the remediation factor (RF) than the control. El-Madabeg soil treated with vinasse sugarcane gave the highest RF values; 6.40, 3.26, and 4.02% for Pb, Zn, and Cu, respectively, than the control. Thus, we identified A. tricolor as a successful ornamental candidate that, along with organic mobilization amendments, most efficiently develop soil health, reduce metal toxicity, and recommend remediation of heavy metal-contaminated soils. Additionally, long-term application of organic mobilization amendments and continued growth of A. tricolor under field conditions could be recommended for future directions to confirm the results.  相似文献   
3.
Soil salinity disrupts the physiological and biochemical processes of crop plants and ultimately leads to compromising future food security. Sodium nitroprusside (SNP), a contributor to nitric oxide (NO), holds the potential to alleviate abiotic stress effects and boost tolerance in plants, whereas less information is available on its role in salt-stressed lentils. We examined the effect of exogenously applied SNP on salt-stressed lentil plants by monitoring plant growth and yield-related attributes, biochemistry of enzymes (superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD)) amassing of leaf malondialdehyde (MDA) and hydrogen peroxide (H2O2). Salinity stress was induced by NaCl application at concentrations of 50 mM (moderate salinity) and 100 mM (severe salinity), while it was alleviated by SNP application at concentrations of 50 µM and 100 µM. Salinity stress severely inhibited the length of roots and shoots, the relative water content, and the chlorophyll content of the leaves, the number of branches, pods, seeds, seed yield, and biomass per plant. In addition, MDA, H2O2 as well as SOD, CAT, and POD activities were increased with increasing salinity levels. Plants supplemented with SNP (100 µM) showed a significant improvement in the growth- and yield-contributing parameters, especially in plants grown under moderate salinity (50 mM NaCl). Essentially, the application of 100 µM SNP remained effective to rescue lentil plants under moderate salinity by regulating plant growth and biochemical pathways. Thus, the exogenous application of SNP could be developed as a useful strategy for improving the performance of lentil plants in salinity-prone environments.  相似文献   
4.
We report here the low temperature emission spectra in the heterometal dinuclear 3d-4f assembled molecular system [(acac)2CrIII(μ-ox)LnIII(HBpz3)2] (Cr(ox)Ln:acac=acetylacetonate, ox2−=oxalate, HBpz3=hydrotris(pyrazol-1-yl)borate; Ln=La, Nd, Ho, Er , Tm and Yb) in comparison with those of Na[Cr(acac)2(ox)] and [(HBpz3)2Ln(μ-ox)Ln(HBpz3)2](Ln=Nd and Er). From 10 to 150 K the Cr(ox)Ln complexes show a broad emission band around 800 nm from the 2E state of Cr(III) moiety. At room temperature no 2E-4A2 emission was observed in the Cr(ox)Ln except for the La and Lu complexes. On warming from 10 to 300 K rapid quenching of the 2E-4A2 emission of Cr(III) is suggested to result from the energy transfer from Cr to Ln in the Cr(ox)Ln. The excitation spectra and the life-time were also measured with monitoring the 4f-4f emission peaks of the Cr(ox)Yb complex.  相似文献   
5.
A new complex [Cu(L1)(NCS)]SCN, where L1 = 3,14-dimethyl-2,6,13,17-tetraazatricyclo( 16.4.0.07,12)docosane is prepared and characterized by single crystal X-ray crystallographic analysis. The complex crystallizes in the triclinic space group P1? with two mononuclear formula units in a cell of dimensions a = 7.9681(2) Å, b = 8.8644(2) Å, c = 18.8165(5) Å, α = 76.758(70)°, β = 78.490(2)° and γ = 77.679(2)°. The Cu(II) ion is five-coordinate in an axially elongated square pyramidal environment, with the four amine N atoms at the equatorial positions and the N atom of one thiocyanate at an apical site. The macrocyclic cyclam moiety adopts a stable trans-III configuration. The Cu–N basal plane bond length has a mean value of 2.037(2) Å. The coordinated Cu–NCS bond length is 2.322(3) Å. The N atom of the thiocyanate anion is connected to the macrocyclic ligand of the cation via an NH…N(CS) hydrogen bond. The UV-visible absorption and IR spectral properties are also discussed.  相似文献   
6.
The sulfonamide core in compounds is effective synthons, which offer exciting perspectives in chemotherapeutic and pharmacological research. In this study, we investigated the molecular interaction of potent sulfonamide derivatives (SDs), 2-benzenesulfonamido-3-methylbutyric acid (BSB) and tetraaquabis{3-methyl-2-[(phenylsulfonyl)amino]butanoate}copper(II) (Cu-BSB), with cationic surfactants, cetyltrimethyl ammonium bromide (CTAB) and ethylhexadecyl dimethyl ammonium bromide (EHDAB), using UV-visible spectroscopy and steady-state fluorescence measurements. Various mathematical models were applied to quantify the effect of cationic surfactants on physicochemical characteristics of BSB and Cu-BSB. These interactions were confirmed by estimating the partition coefficient (Kx), binding capacities (Kb), Stern-Volmer quenching constant (Ksv), and related Gibbs free energies (ΔGb). The in-depth mechanism revealed that the binding mode in SD–surfactants combinational system is spontaneous and quenching exists in static mode initiated by ground-state complex formation. We believe that the true knowledge of host–guest interaction mechanisms concerning model membrane with entrapped moiety can help in better understanding of molecular recognition in related phospholipid membrane models.  相似文献   
7.
Thremogravimetric (TG) studies of a new series of organotin(IV) carboxylates of the general formula RnSnL4-n (where R = CH3, C2H5, C4H9, C6H5, C6H11 and C8H17, n = 2, 3 and L = para-methoxyphenylethanoate anion) have been carried out. Horowitz and Metzger method has been used to calculate thermokinetic parameters. It has been found that diorganotin dicarboxylates have larger activation energy than those of corresponding triorganotin carboxylates. Furthermore, the activation energy, Gibb’s free energy, entropy and enthalpy of diorganotin compounds shows the following trend, (CH3)2SnL2 < (C2H5)2SnL2 < (C4H9)2SnL2 < (C8H17)2SnL2. This is attributed to steady increase in chain length of the alkyl groups. However, triorganotin compounds do not show such behavior.  相似文献   
8.
Low‐operating voltage, high mobility, and stable organic field‐effect transistors (OFETs) using polymeric dielectrics such as pristine poly(4‐vinyl phenol) (PVP) and poly(methyl methacrylate) (PMMA), dissolved in solvents of high dipole moment, have been achieved. High dipole moment solvents such as propylene carbonate and dimethyl sulfoxide used for dissolving the polymer dielectric enhance the charge carrier mobilities by three orders of magnitude in pentacene OFETs compared with low dipole moment solvents. Fast switching circuits with patterned gate PVP‐based pentacene OFETs demonstrated a switching frequency of 75 kHz at input voltages of |5 V|. The frequency response of the OFETs is attributed to a high degree of dipolar‐order in dielectric films obtained from high‐polarity solvents and the resulting energetically ordered landscape for transport. Remarkably, these pentacene‐based OFETs exhibited high stability under bias stress and in air with negligible shifts in the threshold voltage. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013 , 51, 1533–1542  相似文献   
9.
Thermogravimetric (TG) investigations of organotin(IV) carboxylates with the general formula RmSnL4−m (where R=CH3, C2H5, n‐C4H9, C6H5, cyclo‐C6H11, n‐C8H17, m=2, 3, and L=para‐nitrophenylethanoate anion) have been performed. Derivative thermogravimetry (DTG) and differential thermal analysis (DTA) techniques, Horowitz‐Metzger method and the fundamental thermodynamic relations are used to evaluate the thermokinetic parameters of each thermal degradation pattern. Results reveal that the thermal stability is functional to Sn C and Sn O bonds. In the case of R2SnL2, activation energy, reaction order and pre‐exponential factor associated with the bulk degradation processes increase as the alkane chain length increases. Hence, Oct2SnL2 is thermally more stable than Bu2SnL2, which in turn is more resistant to thermal dissociation than Et2SnL2. The same phenomenon is not observed for R3SnL compounds because their degradation is highly irregular. Furthermore, R2SnL2 has larger values of kinetic parameters than those of corresponding triorganotin(IV) para‐nitrophenylethanotes. Thermodynamic parameters of these compounds also reinforce the above facts.  相似文献   
10.
The separation and determination of 19 amino acids were examined using two stages derivatization with trifluoroacetylacetone and ethyl chloroformate from the column HP-5 (30 m × 0.32 mm id) with film thickness 0.25 ??m at an initial column temperature 100 °C for 2 min with ramping of 20 °C min?1 up to 250 °C with nitrogen flow rate of 3 mL min?1. The detection was performed by flame ionization detector. Total separation time was 10 min. The separation was repeatable with relative standard deviation (RSD) (n = 5) within 1.5?C1.9 and 1.3?C1.7% in terms of retention time and peak height/peak area, respectively. The method was applied for the determination of amino acids from skin samples of psoriatic patients (n = 6), arsenicosis patients (n = 5) and normal subjects (n = 9) and variation in the contents of the amino acids was noted. The RSDs for the determination were obtained within 3%.  相似文献   
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