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21.
Wireless body area networks play a vital role in the medical field by saving human lives. It senses the human body condition and transmits it to the respective doctors. The faster the communication, the sensed data can be transmitted faster and the patients in emergency can be treated on time. Therefore, to increase the speed of communication, Unmanned Aerial Vehicles (UAV) are used in biomedical applications. In this flying ad hoc network, there is a possibility of link failure due to the high mobility of UAV. To overcome this issue, a new routing protocol, Mobility Management UAV-based Grouping (MMUG), for biomedical data transmission from one ground station to another via UAV is suggested in this research. The UAV creates the grouping system based on the coverage range of the group head. Group head selects the node that lies closer to the ground station. Group head continuously monitors the mobility of the unmanned aerial vehicles that lie in the coverage range and thus helps to maintain the link stability. The mobility issue will be overcome by using this proposed scheme, and it manages the mobility. The mobility management helps to increase the network performance by increasing the delivery rate and throughput and reducing the drop rate and overhead. Simulation results show that this routing protocol achieves 86% delivery rate and 1.95 Mbps throughput and reduces the drop rate by 14%, control overhead by 23%, and routing overhead by 20%. Moreover, this model achieves higher network performance compared to the existing techniques.  相似文献   
22.
Controlled release of diclofenac sodium (DS) and ibuprofen (IB) drugs through sodium alginate (NaAlg)‐hydroxy ethyl cellulose (HEC) blend polymeric beads has been investigated. Beads were prepared by precipitating the viscous solution of NaAlg and HEC blend in alcohol followed by crosslinking with calcium chloride. Different formulations were developed in bead form by varying the amount of HEC, crosslinking agent, and drug concentration. Swelling studies in water, percent encapsulation of drugs, and release studies were carried out. The DS‐loaded beads have shown better release performance than the IB‐loaded beads. Diffusion parameters were evaluated from the Fickian diffusion theory. Mathematical modeling studies and drug release characteristics through bead matrices were studied by solving Fick's diffusion equation. The results are discussed in terms of drug release patterns and theoretical concentration profiles generated through matrices, considering spherical geometry of the beads. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5708–5718, 2006  相似文献   
23.
Jigging is essentially a cleaning process to separate particles of different relative densities. Usually the jig feed is narrowly sized, however the definition of settling velocity indicates that particle size possibly plays certain role in the process of separation. Limited work is available in published literature on the separation characteristics of constituent size fractions of the feed that has been subjected to jigging. The present communication examines size by size separation characteristics of a Batac jig cleaning metallurgical coal. The characteristics have been measured by Probable Error in Separation, Imperfection and Organic Efficiency. Effect of NGM on the separation characteristics, if any, has also been investigated.  相似文献   
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25.
A novel terpolymer acts as an effective chelating ion exchanger which was synthesized using 2-amino-6-nitro-benzothiazole and semicarbazide with formaldehyde (BSF) by solution condensation technique. Its ion exchange properties was determined against certain metal ions viz. Fe3+, Co2+, Ni2+, Cu2+, Zn2+ and Pb2+ using batch equilibrium technique with different electrolyte concentrations, pH ranges and time intervals. The results of batch studies revealed that the separation of the selected metal ions from the aqueous solution by the terpolymer is found to be excellent compared to the available commercial resins and earlier reported resins. The order of metal ion uptake at higher concentrations by the BSF terpolymer at lower pH is Cu2+ > Ni2+ > Fe3+ and at lower concentration at higher pH is Zn2+ > Co2+ > Pb2+. The reusability of the resin was also reported for its effective ion-exchange behaviour for several cycles. The adsorption isotherm model was evaluated and the results are in good agreement with each other. The order of kinetics was also determined and the resin follows pseudo-second-order kinetics. Moreover, the physico-chemical analysis gives strong evidence for the effective metal ion removal compared with the earlier reported and commercial resins. Earlier, the structure and the properties of the synthesized novel chelating resin were clearly elucidated by elemental, FTIR, UV–Vis, 1H & 13C NMR spectra, GPC, SEM and XRD.  相似文献   
26.
A new class of materials based on inorganic and organic species combined at a nanoscale level has received large attention recently. In this work the idea of producing hybrid materials with controllable properties is applied to obtain foams to be used as catalyst supporting. Hybrids were synthesized by reacting poly(vinyl alcohol) in acidic solution with water glass. The inorganic phase was also modified by incorporating a hexamethyldisiloxane as precursor. The hybrid aerogel powder was analyzed by scanning electron microscopy, TG‐DTA, Nitrogen adsorption–desorption, X‐ray diffraction and fourier transform infrared spectroscopy (FTIR) spectroscopy. The powder obtained had a higher porosity varying from 65 to 90% and the nanopore diameter ranged from 17 to 20 nm. The surface area and nanopore volume decreased as polymer content increased in the hybrids. The sharp decline in the weight observed at around 500°C accompanied an exothermic peak of the DTA curve. The sharp peak was observed around 211°C represents the DTA curve of Poly vinyl alcohol constituent in nano hybrids. The peak at 1638 cm?1 in the FTIR indicated the formation of Si? O? PVA? O? Si bridge in aerogel powder. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   
27.
A naturally occurring fabric belonging to the species Hardwikia binata was extracted from the sheath of stem, bark, and branches of the tree. The fabric specimens were treated with sodium hydroxide and poly (vinyl alcohol). The morphology of the fabric specimens before and after NaOH treatment was studied using scanning electron microscopy technique. Ligno‐cellulosic properties of fabric were analyzed by XRD, FTIR, and thermo gravimetric methods before and after NaOH treatment. Tensile strength and percentage of elongation at break of the fabric were also studied by using a universal testing machine (model AGS‐10kNG). The results showed that the poly (vinyl alcohol)‐treated fabric specimens showed higher tensile strength than sodium hydroxide‐treated fabric specimens. The Binata fabric has good thermal resistance and was also found to increase by alkali treatment. The FTIR method indicates lowering the hemi cellulose and lignin content by alkali treatment in the fabric. Further, the X‐ray diffraction studies revealed an increase in crystallinity of the fabric by alkali treatment. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   
28.
Journal of Materials Science: Materials in Electronics - Green synthesis of multifunctional metal oxide nanoparticles and its composites are widely evaluated for their efficacy in environmental and...  相似文献   
29.
Clean Technologies and Environmental Policy - R245fa and R600 are two working fluids with which organic flash cycle (OFC) yields acceptable thermodynamic and economic performance to recover waste...  相似文献   
30.
An investigation has been made on the cyanoethylation of cotton fabric using aqueous sodium hydroxide with acrylonitrile in presence of solvents acetone and ethanol at different concentrations. The hydrolysis of β‐cyanoethyl ether of cyanoethylated fabric in presence of solvents is studied. The rate of hydrolysis is enhanced by acetone and ethanol concentration. The formation of various products during hydrolysis is analyzed by infrared spectroscopy method while scanning electron microscopy follows the variations in surface morphology. Some of the physical and chemical properties are also studied. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 183–191, 2006  相似文献   
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