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11.
Swee Tiam Tan Junliang Zhao Iwan S. Xiao Wei Sun Xiaohong Tang Jiandong Ye Bosman M. Leijun Tang Guo-Qiang Lo Teo K.L. 《Electron Devices, IEEE Transactions on》2010,57(1):129-133
n-ZnO/n-GaAs heterostructured light-emitting diodes have been fabricated by a low-cost ultrasonic spray pyrolysis technique. Nanoscale interface analysis was carried out with scanning transmission electron microscopy. An ~ 8.6-nm-thick amorphous GaAsZnInO was found in the n -ZnO/n-GaAs interface. A strong and broad white electroluminescence band centered at ~ 525 nm and a weak near-infrared emission peaked at ~ 815 nm were observed when n-GaAs was positively biased. The 815-nm emission is believed to be related to the interface layer, and the 525-nm emission is assigned to the recombination of electrons from conduction band to deep-level holes in the ZnO layer. 相似文献
12.
Nafion‐115/aromatic poly(etherimide) with isopropylidene groups/imidazole membranes for polymer fuel cells 下载免费PDF全文
Agnieszka Iwan Marek Malinowski Andrzej Sikora Igor Tazbir Grzegorz Pasciak Eugenia Grabiec 《应用聚合物科学杂志》2015,132(34)
Proton exchange membrane fuel cells (PEMFCs) with Pt/C gas diffusion electrodes and graphite single‐serpentine monopolar plates were constructed based on an aromatic poly(etherimide) with isopropylidene groups (PI)/imidazole (Im) and a popular Nafion‐115 matrix. The electrochemical properties of PEMFCs were tested at 25 and 60°C. The maximum power density of 171 mW/cm2 and the maximum current density of 484 mA/cm2 were detected for Nafion‐115/PI membrane. For both constructed PEMFCs the efficiency at 0.6 V was found about 41%. Immersion of Nafion‐115 in PI or PI/Im increased the thermal stability and mechanical properties of membranes. Thermal, mechanical properties and morphology of membranes were characterized by TGA, and AFM techniques including force spectroscopy. Interactions between the components in composite membranes were established by FT‐IR. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42436. 相似文献
13.
Lev A. Slobozhanin Valentina M. Shevtsova J. Iwan D. Alexander José Meseguer José M. Montanero 《Microgravity science and technology》2012,24(2):65-77
This paper reviews the dynamics of breaking or oscillating axisymmetric liquid bridges, and estimates of the energy which
is needed to break a liquid bridge. We consider a liquid bridge spanning two coaxial equal disks with sharp edges and held
by surface-tension forces. The liquid volume is assumed to be conserved under perturbations, and the contact lines are pinned
to the disk edges. The perturbations are finite and axisymmetric. An analysis is based on the one-dimensional models previously
used in capillary jet theory and last several decades for study a liquid bridge dynamics. According to the scientific project
JEREMI (Japanese and European Research Experiment on Marangoni Instabilities), the first stage of the space experiment on
ISS will involve an isothermal liquid bridge with a gas blowing parallel to the axial direction of the bridge. The geometry
corresponds to a cylindrical volume liquid bridge coaxially placed into an outer cylinder with solid walls. The gas enters
the annular duct bounded by the outer cylinder and the internal system consisting of supporting vertical rods and the liquid
bridge. Considering that the bridge is small (the rod’s radii are 3 mm) and the gas velocity is typically (0.25 ÷ 0.37) m/s,
the perturbations cannot be considered small. Thus, one may assume that the amplitude of the liquid bridge perturbations is
sufficiently large that departures from linearity must be considered. 相似文献
14.
15.
E. Sienkiewicz-Szłapka B. Jarmołowska S. Krawczuk E. Kostyra H. Kostyra M. Iwan 《International Dairy Journal》2009,19(4):258-263
Two opioid peptides with agonistic (β-casomorphin-5 and β-casomorphin-7) and three with antagonistic (casoxin-6, casoxin-C and lactoferroxin A) activity were determined in three semi-hard cheeses (Edamski, Gouda and Kasztelan) and in two ripening mould cheeses (Brie and Rokpol). β-Casomorphins (BCMs) were found at a higher level in the mould cheeses, whereas the opioid peptides with antagonistic activity were identified at a higher level in the semi-hard cheeses. The opioid activities of the peptide extracts from the cheeses were confirmed using isolated rabbit ileum. 相似文献
16.
Heterogene Keimbildung bei der Entkohlungsreaktion. Homogene Keimbildung bei der Fällungsdesoxydation mit Zirkon. Deutung auf der Grundlage der Volmerschen Theorie der Keimbildung. Kernbildung als geschwindigkeitsbestimmender Schritt. 相似文献
17.
Ermittlung der Zinkaktivität in Mangan-Zink- und Eisen-Zink-Schmelzen. Darstellung der Aktivitätsverläufe im System Mn–Zn für 1300°C und Molenbrüche bis zu xZn = 0,04 sowie im System Fe–Zn für 1585°C und Molenbrüche bis zu xZn = 0,005. 相似文献
18.
Franks W Schenker I Schmutz P Hierlemann A 《IEEE transactions on bio-medical engineering》2005,52(7):1295-1302
A low electrode-electrolyte impedance interface is critical in the design of electrodes for biomedical applications. To design low-impedance interfaces a complete understanding of the physical processes contributing to the impedance is required. In this work a model describing these physical processes is validated and extended to quantify the effect of organic coatings and incubation time. Electrochemical impedance spectroscopy has been used to electrically characterize the interface for various electrode materials: platinum, platinum black, and titanium nitride; and varying electrode sizes: 1 cm2, and 900 microm2. An equivalent circuit model comprising an interface capacitance, shunted by a charge transfer resistance, in series with the solution resistance has been fitted to the experimental results. Theoretical equations have been used to calculate the interface capacitance impedance and the solution resistance, yielding results that correspond well with the fitted parameter values, thereby confirming the validity of the equations. The effect of incubation time, and two organic cell-adhesion promoting coatings, poly-L-lysine and laminin, on the interface impedance has been quantified using the model. This demonstrates the benefits of using this model in developing better understanding of the physical processes occurring at the interface in more complex, biomedically relevant situations. 相似文献
19.
Si-doped β-Ga2O3 was generally activated by high-temperature annealing (over 600?°C) due to its strong bonding energy. Considering the electronic applications using β-Ga2O3 such as various power devices with low power consumption, it is strongly required to decrease the device process temperature including the impurity activation process. In this article, in order to decrease the impurity activation process temperature, we proposed the rapid thermal annealing (RTA) treatment to activate the Si atoms in the β-Ga2O3 films since RTA treatment can give the high thermal energy to specimen in a short time and investigated the influence of RTA treatment with various temperatures on conductivity activation energy, and structural properties of Si-doped β-Ga2O3 film. Si-doped β-Ga2O3 films were hetero-epitaxially grown on c-plane sapphire substrate by pulsed laser deposition method. Crystallinity, surface roughness, and electrical properties of specimens were investigated by changing the RTA temperatures. Crystallinity and surface roughness of Si-doped β-Ga2O3 films were not significantly influenced by RTA treatment at temperatures range of 100–700?°C. Conductivity activation energy of specimens with RTA treatment was about 50–100?meV and did not depend on RTA temperatures. As a result, even Si-doped β-Ga2O3 film with RTA treatment at 100?°C showed a relatively good conductivity. Based on the experimental results in this study, it can be said that RTA treatment is useful method to decrease the temperature of activation process for Si-doped β-Ga2O3 thin films without serious structural degradations. 相似文献
20.