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1.
Cellulose - There has been significant interest over recent years in the production and application of sustainable and green materials. Among these, nanocellulose has incurred great interest...  相似文献   
2.
Halotolerant bacteria associated with Psoralea corylifolia L., a luxuriantly growing annual weed in salinity-affected semi-arid regions of western Maharashtra, India were evaluated for their plant growth-promoting activity in wheat. A total of 79 bacteria associated with different parts viz., root, shoot and nodule endophytes, rhizosphere, rhizoplane, and leaf epiphytes, were isolated and grouped based on their habitat. Twelve bacteria isolated for their potential in plant growth promotion were further selected for in vitro studies. Molecular identification showed the presence of the genera Bacillus, Pantoea, Marinobacterium, Acinetobacter, Enterobacter, Pseudomonas, Rhizobium, and Sinorhizobium (LC027447-53; LC027455; LC027457, LC027459, and LC128410). The phylogenetic studies along with carbon source utilization profiles using the Biolog® indicated the presence of novel species and the in planta studies revealed promising results under salinity stress. Whereas the nodule endophytes had minute plant growth-promoting (PGP) activity, the cell free culture filtrates of these strains enhanced seed germination of wheat (Triticum aestivum L). The maximum vigor index was monitored in isolate Y7 (Enterobacter sp strain NIASMVII). Indole acetic acid (IAA) production by the isolates ranged between 0.22 and 25.58 μg mL?1. This signifies the need of exploration of their individual metabolites for developing next-generation bio-inoculants through co-inoculation with other compatible microbes. This study has potential in utilization of the weed-associated microbiome in terms of alleviation of salinity stress in crop plants.  相似文献   
3.
The concept of a convex metric space was introduced by Takahashi [10]. He observed that it is possible to generalize fixed point theorems in Banach spaces. Subsequently, Machado [8], Itoh [5], Naimpally, Singh and Whitfield [9] and Beg and Azam [2], among others have studied fixed point theorems in convex metric spaces. This paper is a continuation of these investigations.  相似文献   
4.
We report the observation of enhanced near-infrared transmission through arrays of subwavelength coaxial metallic structures compared with that through comparable diameter hole arrays as a result of localized electromagnetic modes supported by the complex coaxial unit cell. Polarization and angle-dependent transmission measurements clearly demonstrate the coupling between this localized mode and delocalized surface plasmon modes. A generalized, multiple discrete states Fano line shape provides a good fit to the experimental results.  相似文献   
5.
Analytical solutions for the peristaltic flow of a magneto hydrodynamic(MHD) Sisko fluid in a channel, under the effects of strong and weak magnetic fields, are presented. The governing nonlinear problem, for the strong magnetic field,is solved using the matched asymptotic expansion. The solution for the weak magnetic field is obtained using a regular perturbation method. The main observation is the existence of a Hartman boundary layer for the strong magnetic field at the location of the two plates of the channel. The thickness of the Hartmann boundary layer is determined analytically. The effects of a strong magnetic field and the shear thinning parameter of the Sisko fluid on the velocity profile are presented graphically.  相似文献   
6.
7.
Summary A method for the preparation of ore solutions by grinding the ore with distilled water is developed for the analysis of minerals and ores in the field by the circular thin-layer Chromatographic technique.
Zusammenfassung Die Herstellung von Erzlösungen durch Mahlen des Erzes mit dest. Wasser zur Feldanalyse von Mineralen und Erzen durch Ring-Dünnschichtchromatographie wird empfohlen.
  相似文献   
8.
In the present investigation, p-morpholinomethylcalix[4]arene (1) has been examined as a carrier in supported liquid membrane (SLM) for Cu(II) transport. The influence of different parameters, such as solvent, membrane dipping time, support membrane, co-anions, donor and acceptor pH, and carrier concentration on Cu(II) transport, was checked. The permeability values were calculated by using Danesi mass transfer model. Higher Cu(II) permeability was observed in diphenyl ether, with 1 h dipping time, Celgard 2500 and Cl? as co-anion. The optimum pH for donor phase was 2 and that for acceptor phase was neutral at 10?3 M carrier concentration. Diffusion coefficients were calculated using Reinhoudt's model, lag time measurements as well as by Wilke–Chang relation and compared. The transport was found to be diffusion-controlled in the membrane phase and the diffusion coefficient was calculated to be 1.54 × 10?10 m/s whereas the extraction constant was calculated to be 1.19 × 10?5 m/s.  相似文献   
9.
5‐Fluorouracil (5‐FU) is widely used against many types of solid cancer in clinics. However, because of its limitations such as short half‐life, poor oral absorption and rapid clearance by dihydropyrimidine dehydrogenase have limited its applications. In current study, new in situ chemically grafted thermogels for prolonged drug release are formed on the basis of poloxamer 407 (PF127) and carboxymethyl chitosan (CMCS) using glutaraldehyde as cross‐linking agent. The phase transition from sol to gel state at body temperature was confirmed by tube titling, rheological analysis, and optical transmittance determinations. Swelling and drug release experiments conducted at various pH and temperature demonstrated that developed formulations are thermoresponsive with maximum swelling and release below critical gelation temperature (CGT) (pH 7.4, 25°C). Cells growth inhibition study confirmed the biocompatibility of thermogels against L929 cell lines. Methyl thiazolyl tetrazolium (MTT) assay confirmed that 5‐FU–loaded thermogels have the potential to cause cells death against HeLa and MCF‐7 cancer lines. The IC50 values calculated for pure 5‐FU solution (27 ± 0.81 μg/mL for HeLa and 24 ± 0.58 μg/mL for MCF‐7) were found higher in comparison with 5‐FU–loaded thermogels, against HeLa (17 ± 0.39 μg/mL) and MCF‐7 (14 ± 0.67 μg/mL). Fourier transform infrared (FTIR) confirmed the new structure formation and chemical grafting between PF127 and CMCS. Thermogravimetric (TG) and differential scanning calorimetry (DSC) analyses proved the phase transition around physiologic temperature range, while scanning electron microscopy (SEM) analysis displayed the presence of connected pores in the cross section of thermogels facilitating the uptake of solvents and drug particles. Altogether, results concluded that developed chemically grafted thermogels can be used in vivo for prolonged drug release after subcutaneous administration.  相似文献   
10.
We experimentally demonstrate the first midinfrared (mid-IR) resonant magnetic nanostructures exhibiting a strong magnetic response corresponding to a negative permeability. This result is an important step toward the achievement of a negative refractive index in the IR. The possibility of extending negative permeability to higher frequencies is discussed; a structure with a negative effective permeability at a near-IR resonance frequency of 230 THz (1.3 microm) is proposed.  相似文献   
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