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91.
Kalyani Patrikar Nakul Jain Dwaipayan Chakraborty Priya Johari Valipe Ramgopal Rao Dinesh Kabra 《Advanced functional materials》2019,29(8)
Charge transport properties of common donor copolymers in organic photovoltaics, poly({4,8‐bis[(2‐ethylhexyl)oxy]benzo[1,2‐b:4,5‐b′]dithiophene‐2,6‐diyl}{3‐fluoro‐2‐[(2‐ethylhexyl)carbonyl]thieno[3,4‐b]thiophenediyl}) (PTB7) and poly([2,6′‐4,8‐di(5‐ethylhexylthienyl)benzo[1,2‐b;3,3‐b]dithiophene]{3‐fluoro‐2[(2‐ethylhexyl) carbonyl]thieno[3,4‐b]thiophenediyl}) (PTB7‐Th), with molecular structures differing only in the pendant group, are studied. This is the first report of field‐effect transistor mobility (µFET) of PTB7‐Th (0.14 cm2 V?1 s?1) and the highest µFET for PTB7 (0.01 cm2 V?1 s?1). µFET of PTB7‐Th is found to be almost one order of magnitude higher than PTB7. To understand the influence of molecular structure on charge transport, hole reorganization energy (λh) is calculated from first‐principles. λh of PTB7‐Th (≈150 meV) is found to be lower than PTB7 (≈346 meV). Further, the ratio of hopping rate versus square of charge transfer integral calculated from Marcus theory using λh for these systems is found to indicate a higher rate of hole transfer across dimers or homojunction interface for PTB7‐Th. These results are supplemented by experimentally determined λ using bulk‐heterojunction organic solar cells, where λPTB7‐Th≈200 meV and λPTB7≈310 meV follow a similar trend. The effective hole‐mobility estimation from BHJ devices correlates well with these λ values. This study provides understanding of charge transport properties via reorganization energy, as a function of pendant group without altering the backbone of the chains. 相似文献
92.
With the significant rise of low power embedded devices in various applications of both consumer and commercial usage, the surge for continuous power requirements has initiated promising research toward alternative sources of energy. It includes the domain of wireless power transmission, internet‐of‐things, wireless sensor nodes, machine‐to‐machine, and radio frequency identification. Thus, the overall scope of this review article is to witness microwave antennas and its implementation in RF energy harvesting system through ambient RF signals. For this reason, unified understanding of classical electromagnetism is needed; beginning with the fundamentals of RF transmission and the exploration of concepts such as Fraunhofer's Distance and Friis Transmission Equation. It is followed up by the analogy of dependency of parameters like circuit build‐up, conversion efficiencies and amount of power harvested, which is quite crucial from the rectifier point‐of‐view. For better improvisement in RF energy harvesting systems, five different cases of monopole antennas are explored with reflector surfaces such as PEC (perfect electrical conductor) and AMC (artificial magnetic conductor) integrated with the rectifier circuit. Implementation with wide diversity has proposed a generalized solution for achieving tradeoffs: polarization and pattern diversity with consistent system efficiency; leads to clean and sustainable energy for low power‐embedded devices. 相似文献
93.
Priya Saha Mrinal Kanti Bhowmik Debotosh Bhattacharjee Barin Kumar De Mita Nasipuri 《Multimedia Tools and Applications》2016,75(24):16781-16807
Facial expression is one of the major distracting factors for face recognition performance. Pose and illumination variations on face images also influence the performance of face recognition systems. The combination of three variations (facial expression, pose and illumination) seriously degrades the recognition accuracy. In this paper, three experimental protocols are designed in such a way that the successive performance degradation due to the increasing variations (expressions, expressions with illumination effect and expressions with illumination and pose effect) on face images can be examined. The whole experiment is carried out using North-East Indian (NEI) face images with the help of four well-known classification algorithms namely Linear Discriminant Analysis (LDA), K-Nearest Neighbor algorithm (KNN), combination of Principal Component Analysis and Linear Discriminant Analysis (PCA + LDA), combination of Principal Component Analysis and K-Nearest Neighbor algorithm (PCA + KNN). The experimental observations are analyzed through confusion matrices and graphs. This paper also describes the creation of NEI facial expression database, which contains visual static face images of different ethnic groups of the North-East states. The database is useful for future researchers in the area of forensic science, medical applications, affective computing, intelligent environments, lie detection, psychiatry, anthropology, etc. 相似文献
94.
Sample preparation method considerations for integrated transcriptomic and proteomic analysis of tumors 下载免费PDF全文
Anupama Rajan Bhat Manoj Kumar Gupta Priya Krithivasan Kunal Dhas Jayalakshmi Nair Ram Bhupal Reddy Holalugunda Vittalamurthy Sudheendra Sandip Chavan Harsha Vardhan Sujatha Darsi Lavanya Balakrishnan Shanmukh Katragadda Vikram Kekatpure Amritha Suresh Pramila Tata Binay Panda Moni A. Kuriakose Ravi Sirdeshmukh 《Proteomics. Clinical applications》2017,11(3-4)
95.
The characteristics of MANET such as decentralization, dynamic topology and openness are susceptible for security threats. To overcome the security threats and to provide a reliable network to transmit packets, a need for trust based routing arises. Moreover, the trust along with energy requirement on ad hoc on demand distance vector have paved way for the development of the newly proposed algorithm named as refined trust and energy based ad hoc on demand distance vector algorithm which is the refined form of the existing trust and energy based ad hoc on demand distance vector algorithms and the classical AODV. In this paper, the refinement parameter is the trust. Moreover, Bayesian probability is introduced in this paper for trust management due to its ability to handle uncertainty for obtaining the refined form of Trust calculation. The proposed algorithm routes the packets from the source to destination not through the shortest route but by selecting a reliable route which consumes low energy and trustful for sending the packets. The simulation results obtained from this work show that the proposed algorithm performs better than the existing algorithms in terms of Trust based routing and energy efficiency. 相似文献
96.
Min Gyu Kang Seul‐Yi Lee Deepam Maurya Christopher Winkler Hyun‐Cheol Song Robert B. Moore Mohan Sanghadasa Shashank Priya 《Advanced functional materials》2017,27(29)
1D ferroelectric nanostructures are promising for enhanced ferroelectric and piezoelectric performance on the nanoscale, however, their synthesis at the wafer scale using industrially compatible processes is challenging. In order to advance the nanostructure‐based electronics, it is imperative to develop a silicon‐compatible growth technique yielding high volumetric density and an ordered arrangement. Here, a major breakthrough is provided in addressing this need and ordered and close‐packed single crystalline ferroelectric nanorod arrays, of composition PbZr0.52Ti0.48O3 (PZT), grown on commercial grade 3 in. silicon wafer are demonstrated. PZT nanorods exhibit enhanced piezoelectric and ferroelectric performance compared to thin films of similar dimensions. Sandwich structured architecture utilizing 1D PZT nanorod arrays and 2D reduced graphene oxide thin film electrodes is fabricated to provide electrical connection. Combined, these results offer a clear pathway toward integration of ferroelectric nanodevices with commercial silicon electronics. 相似文献
97.
P. Michael Preetam Raj Amlan Ranjan Kalita Mantu K. Hudait Shashank Priya 《Integrated ferroelectrics》2018,192(1):16-27
Pt/BaTiO3-BiFeO3/Nb:SrTiO3 based memristors were fabricated and their current–voltage (I–V) characteristics were studied in order to facilitate integration with analog/digital computations. Piecewise non-linear I–V characteristic equations of the ferroelectric memristor were obtained using non-linear regression techniques. An equivalent circuit for the fabricated memristors was obtained comprising of internal current, film resistance, and voltage dependent resistance. Utilizing the equivalent circuit model, a three bit general purpose Finite State Machine was developed and simulated results were found to match with the fabricated FSM device results. 相似文献
98.
A. Subramania N.T. Kalyana Sundaram R. Sathiya Priya K. Saminathan V.S. Muralidharan T. Vasudevan 《Journal of Applied Electrochemistry》2004,34(7):693-696
New and effective aldimine types of corrosion inhibitors namely, N-methylidene octylamine (MOA), N-ethylidene octylamine (EOA) and N-propylidene octylamine (POA) have been synthesized. Their inhibition efficiency was investigated for the corrosion of mild
steel in 1 M HCl solution by various corrosion monitoring techniques. A preliminary screening of the inhibition efficiency
of the inhibitors was carried out by weight loss and gasometric studies. They were found to behave as good inhibitors in 1
M HCl solution. Potentiodynamic polarization measurements show that aldimines are mixed type inhibitors. The extent of the
decrease in the hydrogen permeation current through the mild steel surface was studied by the hydrogen permeation technique
and it was found that the decrease was in the order POA > EOA > MOA. Double layer capacitance and charge transfer resistance
values were derived from Nyquist plots obtained from AC impedance studies. The adsorption of these compounds on mild steel
from 1 M HCl solution obeys the Temkin adsorption isotherm. 相似文献
99.
Shashank Priya Hyeoung-Woo Kim Kenji Uchino 《Journal of the American Ceramic Society》2004,87(10):1907-1911
Pb(Zr,Ti)O3 –Pb(Mn1/3 Nb2/3 )O3 (PZT–PMnN) system has been studied for high-power piezoelectric applications. This study investigates this system to find out the composition with high-power density piezoelectric characteristics and low tem-perature coefficient of resonance frequency (TCF). It was found that the composition 0.9PZT–0.1PMnN (Zr/Ti = 0.51/0.49) modified with 6 mol% Sr exhibits a TCF of −8 ppm/°C (−20 to +80°C). Further, the dielectric and piezoelectric properties of this composition are as follows: k p = 0.53; Q m = 800; d 33 = 274; ε33 /ε0 = 1290 and tan δ=1.1%, which shows the suitability of this composition for ultrasonic devices used under fluctuating thermal environment. 相似文献
100.
Priya Varsani Ayo Afonja David E. Williams Ivan P. Parkin Russell BinionsAuthor vitae 《Sensors and actuators. B, Chemical》2011,160(1):475
Solid-state metal oxide gas sensors with zeolite overlayers have been developed as a means to improve sensor selectivity. Screen printed tungsten oxide (WO3) sensors were modified by the addition of acidic and catalytic zeolite layers. The sensors were characterised before and after sensing experiments using X-ray diffraction, energy dispersive X-ray analysis and scanning electron microscopy. The sensors were tested against various gases and gas mixtures to assess their discriminatory behaviour. The results show that the sensors response can be tailored to be selective towards specific target gases by changing the zeolite; for example the H-ZSM-5 sensor gave a response 19 times greater to NO2 than an unmodified control sensor. It was observed that the WO3 based gas sensors showed a remarkable selectivity towards NO2 in a gas mixture. The sensors also showed high levels of stability and sensitivity and have potential to be used in electronic nose technology. 相似文献