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1.
Context: Docosahexanoic acid (DHA) is an essential omega-3 fatty acid for normal brain development and its use has increased considerably in recent years.

Objective: The aim of this study is to develop and evaluate self-nanoemulsifying drug delivery systems (SNEDDS) of DHA for improved palatability, dispersibility and bioavailability.

Methods: The SNEDDS were prepared and evaluated for miscibility, employing different combinations of olive oil and soyabean oil as oil phase, Span 80, Span 20, soya phosphatidylcholine, Labrafil M 1944 CS as surfactants while Tween 80, PEG 400, Cremophor RH40 and propylene glycol as cosurfactants. Thermodynamically stable SNEDDS were characterized for dispersibility, self-emulsification time, droplet size, zeta potential along with sensory analysis. The optimized formulation was subjected to ex vivo and in vivo evaluation such as intestinal permeability, memory performance test, brain concentration and histopathology studies.

Results: The optimized SNEDDS formulation showed emulsification time of 27?±?4.7?s with droplet size of 17.6?±?3.5?nm and zeta potential of??37.6?±?0.5?mV. Intestinal absorption study depicted 18.3%, 21.5%, 41.5%, 98.7% absorption of DHA with SNEDDS-based formulation in comparison to 8.2%, 15.1%, 28.8%, 46.1% absorption of DHA with oil-based marketed formulation after 0.5, 1, 2 and 4?h. DHA concentration in brain homogenate was found to be increased to 2.6-fold in comparison to DHA-marketed formulation. This could be ascribed to enhanced dispersibility and bioavailability of DHA from nanosized formulation.

Conclusion: The developed formulation led to enhanced dispersibility and bioavailability of DHA due to the formation of nanodroplets.  相似文献   
2.
The mixing torque behavior of ter blends of isotactic-polypropylene (iPP) with ethylene-propylene diene rubber (EPDM)/Nitrile rubber (NBR) was studied with the help of Rheometer using resole type phenolic resin as a cross-linking agents. Systematic changes with varying blend composition were observed in stress-strain behavior in the yield region viz., width of yield peak, work of yield, yield stress and yield strain. Analysis of yield stress data was made on the basis of various mathematical expressions of first power and two-thirds power laws of blend composition dependence and the porosity model. It led to consistent result from the expressions about the variation of stress concentration effect in both uncross-linked and cross-linked blend systems. With the aid of scanning electron microscopy (SEM) shapes and sizes of dispersed elastomer phase (EPDM / NBR) domains at varying blend compositions were studied.  相似文献   
3.
Wireless Personal Communications - The Electrocardiogram (ECG) signal is used to record the electrical activity of heart. The subtle variations in ECG attributes are used by cardiologists for...  相似文献   
4.
An attempt is made to explain the pressure dependence of the superconducting transition temperatureT c of aluminum. The model calculation is essentially the same as that of Ott and Sorbello, with the difference that here the effect of zone boundaries on the density of states is included. The model calculations given here can explain both the low pressure and the high pressure data and suggest that one should include the effect of zone boundaries to explain theT c data for the complete pressure range.  相似文献   
5.

The paper proposes a method to improve the performance of speech communication system in a highly noisy industrial environment. For the improvement, different speech signals are considered which includes signals from different environments such as car noise, railway station, babble noise, street noise which are corrupted with additional noise as input data set for processing. This database is processed using suitable filters which will remove the effect of noise to some extent. Different algorithms have been proposed to minimize the effect of noise to a certain limit. The denoising algorithms are generally the different wavelet thresholding method which removes the noise from the speech signal. Many researchers have worked on soft and hard thresholding for image processing. The proposed method of hybrid thresholding comprises of both soft and hard thresholding process which is comparatively better method than the previous methods. The method can be implemented for the non-stationary noise and it also removes the problems of edges. Unlike the traditional way of using single value, different values are used for the adaptive filtering to remove the edges. During the course of experiments, the dataset of IIIT-H with a set of noisy files from Noizeus and AURORA database having sampling rate of 16 kHz has been used. Results are calculated with subjective and objective measures for fine and broad level quality assessment. SNR, SSNR, PSNR, NRMSE, and PESQ parameters are used as performance parameters and outperform with other combinations as compared to conventional methods. The hybrid threshold method yields better results with significant improvement in speech quality and intelligibility.

  相似文献   
6.
Melt mixed and injection molded hydroxyapatite (Hap) filled high‐density polyethylene/ultrahigh molecular weight polyethylene composites were assessed for their thermal, structural, morphological, and mechanical attributes. Differential scanning calorimetry was conducted to analyze the effect of Hap loading on various thermal transitions and their associated enthalpies. The microstructural attributes were characterized by conducting wide angle X‐ray diffraction and scanning electron microscopy (SEM) of cryo‐fractured surface. SEM micrographs of tensile fractured surface revealed the systematic reduction in the size of microfibrils indicating the suppression of local deformation. Improvement in low‐strain mechanical response and flexural properties accompanied with a consistent decrease in strain‐at‐break and toughness was witnessed with increasing Hap content. Toughness aspects were critically discussed in the realms of quasi‐static, dynamic mechanical and sudden impact testing approach. Dynamic mechanical analysis demonstrated the presence of prominent α and γ transitions in the crystalline and amorphous phase respectively. Tensile fractured surface morphologies of the investigated composites revealed a switch‐over from matrix dominated plastic deformation to Hap controlled quasi‐brittle fracture. Thus, our study fundamentally deals with the feasibility of designing polyethylene/Hap composites with superior mechanical properties for biomedical applications, especially for orthopedic implants. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41251.  相似文献   
7.
Chia seed oil (CSO) has been recently gaining tremendous interest as a functional food. The oil is rich in with polyunsaturated fatty acids (PUFAs), especially, alpha linolenic acid (ALA), linoleic acid (LA), tocopherols, phenolic acids, vitamins, and antioxidants. Extracting CSO through green technologies has been highly efficient, cost-effective, and sustainable, which has also shown to improve its nutritional potential and proved to be eco-friendly than any other traditional or conventional processes. Due to the presence of valuable bioactive metabolites, CSO is proving to be a revolutionary source for food, baking, dairy, pharmaceutical, livestock feed, and cosmetic industries. CSO has been reported to possess antidiabetic, anticancer, anti-inflammatory, antiobesity, antioxidant, antihyperlipidemic, insect-repellent, and skin-healing properties. However, studies on toxicological safety and commercial potency of CSO are limited and therefore the need of the hour is to focus on large-scale molecular mechanistic and clinical studies, which may throw light on the possible translational opportunities of CSO to be utilized to its complete potential. In this review, we have deliberated on the untapped therapeutical possibilities and novel findings about this functional food, its biochemical composition, extraction methods, nutritional profiling, oil stability, and nutraceutical and pharmaceutical applications for its health benefits and ability to counter various diseases.  相似文献   
8.
9.
An innovative idea of extracting kinetic energy from man-made wind resources using ducted turbine system for on-site power generation is introduced in this paper. A horizontal axis ducted turbine is attached to the top of the chimney to harness the kinetic energy of flue gases for producing electricity. The turbine system is positioned beyond the chimney outlet, to avoid any negative impact on the chimney performance. The convergentdivergent duct causes increase in the flue gas velocity and hence enhances the performance of the turbine. It also acts as a safety cover to the energy recovery system. The results from the CFD based simulation analysis indicate that significant power 34 kW can be harnessed from the chimney exhaust. The effect of airfoils NACA4412 and NACA4416 and the diffuser angle on the power extraction by the energy recovery system using a 6-bladed ducted turbine has been studied with the CFD simulation. It is observed that the average flue gas velocity in the duct section at the throat is approximately twice that of the inlet velocity,whereas maximum velocity achieved is 2.6 times the inlet velocity. The simulated results show that about power may be extracted from the chimney flue gases of 660 MW power plant. The system can be retrofitted to existing chimneys of thermal power plants, refineries and other industries.  相似文献   
10.
In this study, copper nanoparticles (Cu NPs) were synthesised by using diethylenetriamine as a protective agent in chemical reduction method. The obtained nanoparticles were characterised by various spectroscopic techniques like powder X-ray diffraction (PXRD), Fourier transform infrared (FTIR), UV–visible spectroscopy, energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and thermal analysis (TG/DTA). The structure and composition were estimated by PXRD, FTIR, EDS, UV–visible and TG/DTA techniques, while particles size and morphology behaviours were investigated by SEM and TEM instrumentation. A noteworthy, average particle size of nanoparticles was found around 40 nm with spherical shapes. Furthermore, the applications part of NPs were studied as a catalyst for one-pot solvent-free green synthesis of 3,4-dihydropyrano[c]chromenes from different aromatic aldehydes, malonitrile and 4-hydroxycoumarin by stirring at 80 °C. Moreover, the antibacterial properties of NPs were assessed in vitro against human bacterial pathogen such as Staphylococcus aureus, Escherichia coli, Klebsiella sp. and Pseudomonas aruginosa using agar well diffusion method. Gram positive bacteria S. aureus (18 mm) exhibited a maximum zone of inhibition at 60 µg/ml of Cu NPs. Nonetheless, antibacterial activities of Cu NPs (10–100 µg) were compared with four well-known antibiotics likes amikacin (30 mcg), ciprofloxacin (5 mcg), gentamicin (5 mcg) and norfloxacin (10 mcg). This study indicates that Cu NPs exhibited a strong antibacterial activity against all the test pathogens even at lower concentration.  相似文献   
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