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101.
Okoli C Fornara A Qin J Toprak MS Dalhammar G Muhammed M Rajarao GK 《Journal of nanoscience and nanotechnology》2011,11(11):10201-10206
The application of surface modified magnetic adsorbent particles in combination with magnetic separation techniques has received considerable awareness in recent years. There is a particular need in protein purification and analysis for specific, functional and generic methods of protein binding on solid supports. Nanoscale superparamagnetic iron oxide particles have been used to purify a natural coagulant protein extracted from Moringa oleifera seeds. Spectrophotometric analysis of the coagulant protein was performed using synthetic clay solution as substrate. Protein binding with carboxyl and silica surface modified superparamagnetic iron oxide nanoparticles (SPION) were compared with the known carboxyl methyl cellulose (CMC) beads of approximately 1 microm. SPION modified with carboxyl surface showed higher binding capacity towards the coagulant protein compared to the CMC beads. The high surface area to volume ratio of the carboxyl-coated SPION resulted in high binding capacity and rapid adsorption kinetics of the crude protein extract. The purification and molecular weight of coagulant protein is analyzed by SDS-PAGE. This approach utilizes the most efficient, feasible and economical method of coagulant protein purification and it can also be applicable to other proteins that possess similar properties. 相似文献
102.
Celalettin Özdemir Muhammed K Öden Serkan Şahinkaya Dünyamin Güçlü 《Coloration Technology》2011,127(4):268-273
In the present study, Fenton and sono‐Fenton processes were applied to the oxidative decolorisation of synthetic textile wastewater including CI Reactive Orange 127 and polyvinyl alcohol. Process optimisation [pH, ferrous ion (Fe2+) and hydrogen peroxide (H2O2)], kinetic studies and their comparison were carried out for both of the processes. The sono‐Fenton process was performed by indirect sonication in an ultrasonic water bath, which was operated at a fixed 35‐kHz frequency and 80 W power. The optimum conditions were determined as [Fe2+] = 20 mg l?1, [H2O2] = 15 mg l?1 and pH = 3 for the Fenton process and [Fe2+] = 25 mg l?1, [H2O2] = 5 mg l?1 and pH = 3 for the sono‐Fenton process. The colour removals were 89.9% and 91.8% by the Fenton and sono‐Fenton processes, respectively. The highest decolorisation was achieved by the sono‐Fenton process because of the production of some oxidising agents as a result of sonication. Consequently, ultrasonic irradiation in the sono‐Fenton process slightly increased the colour removal to 91.8%, while decreasing the hydrogen peroxide dosage to one‐third of that of the Fenton process. 相似文献
103.
Analytical model for connectivity of vehicular ad hoc networks in the presence of channel randomness
A vehicular ad hoc network (VANET) is a highly mobile wireless ad hoc network formed by vehicles equipped with communication facilities. Developing multihop communication in VANETs is a challenging problem because of rapidly changing network topology and frequent network disconnections. This paper investigates the network connectivity probability of one‐dimensional VANET in the presence of channel randomness. Network connectivity is one of the most important issues in VANETs, because the dissemination of time‐critical information requires, as a preliminary condition, the network to be fully connected. We present an analytical procedure for the computation of network connectivity probability, taking into account the underlying wireless channel. Three different fading models are considered for the connectivity analysis: Rayleigh, Rician, and Weibull. A distance‐dependent power law model is employed for the pathloss in a vehicle‐to‐vehicle channel. Furthermore, the speed of each vehicle on the highway is assumed to be a Gaussian distributed random variable. The analysis provides a general framework for investigating the dependence of various parameters such as vehicle arrival rate, vehicle density, vehicle speed, highway length, and various physical layer parameters such as transmit power, receive signal‐to‐noise ratio threshold, path loss exponent, and fading factors (Rician and Weibull) on VANET connectivity. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
104.
Muhammed Raza Shah Muhammed Zahid Raza Nisar Ahmed 《Petroleum Science and Technology》2013,31(1):85-95
ABSTRACT Non-isothermal thermogravimetry (Tg) and derivative thermogravimetry (DTG) studies are reported on a Pakistan lignite and Pakistan subbituminous coal. The burning profiles of the samples shows multi-peak configuration which is indicative of the heterogeneity of organic matter. The volatile matter profiles of these samples are characterized by rate of weight loss. 相似文献
105.
Muhammed Faheem Lavaggi Tania Advani Suresh Mirotznik Mark Gillespie John W. 《Journal of Materials Science》2021,56(32):17877-17914
Journal of Materials Science - Carbon–carbon composites (CCCs) are a unique form of carbon fiber-reinforced materials that exhibit excellent thermomechanical properties under extreme... 相似文献
106.
Muhammed Iberia Aydin Ibrahim Dincer Harry Ha 《International Journal of Hydrogen Energy》2021,46(47):23997-24010
Consumption of fossil fuels, which makes an immense contribution to greenhouse gas emissions, must be reduced. Hydrogen emerges as a unique solution to serve as fuel, energy carrier and feedstock because it is a clean, abundant, environmentally friendly and energy intensive gas. This study aims to investigate the development of a potential hydrogen hub located in Oshawa, Canada, which is aimed to provide a hydrogen infrastructure for future hydrogen economy. Numerous life cycle assessment and cost assessment studies are conducted to investigate what benefits such a hydrogen will bring to the city. The results show that fuel cell electric buses emit 89% fewer pollutants. Also, 60% of overall CO2 reduction is possible with a gradual transition to fuel cell technology within 20 years. However, in order for hydrogen infrastructure and costs to compete with fossil fuels, high-scale projects need to be developed with governmental incentives. 相似文献
107.
The extraction of nitric acid from concentrated phosphoric acid solutions by methyl isobutyl ketone (MIBK) dissolved in aromatic diluent has been studied. Nitric acid can be effectively removed by MIBK from the solutions containing 50–75% H3P04. With increasing the concentration of either H3PO4 or MIBK, the distribution coefficient of HN03 increases but the separation factor for HN03 against H3PO4 decreases. However, it is possible to achieve a complete removal of HN03 in a few of stages and the coextraction of H3PO4 can be limited to less than 1%. 相似文献
108.
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