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51.
Effects and properties of poly(sodium α-hydroxyacrylate) (PHA) on removal of stearic and oleic acids from cellulosic filter paper under various wash conditions were evaluated and compared with those of sodium dodecyl sulfate (SDS) by using differential scanning calorimetry. PHA had a much greater effect on the removal of stearic and oleic acids than SDS under the same washing conditions. PHA produces complexes with fatty acids on filter paper during the washing process, and in DSC these complexes have endothermic peaks at temperatures higher than the melting point of the fatty acids. The complexes are formed at temperatures both below and above the melting point of the fatty acid and are removed completely from filter paper by rinsing. The conditions of temperature, time, and PHA concentration during washing all affected the formation of the complex and the removal of fatty acid. Whether the fatty acid chain was saturated or not did not affect the formation of a complex.  相似文献   
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53.
Compressive creep tests of UC1.5 pellets were conducted in the temperature range between 1200 and 1400 °C and in the stress range between 3000 psi (20.7 MN/m2) and 15000 psi (103.5 MN/m2). The data of the present creep test are relatively well fined to the equation, geα exp(?ΔH(σ)RT)exp(βσ), where ΔH(σ) = 41 kcal/mol + 0.894 kcal.m2/mol.MN σ and β is 0.02, 0.03 and 0.07 m2/MN at 1200, 1300 and 1400°C, respectively. The creep rate of UC1.5 pellets is directly related to the phase change during the creep test and decreases with an increasing amount of U2C3 phase. The rate of U2C3 formation was not enhanced by the action of compression stress as compared with the case without stress. Microstructure of U2C3 formation after the creep test was the same as in pellet annealed stress.  相似文献   
54.
55.
We propose and demonstrate a voltage-pulse-induced electromigration technique, in which electromigration in a gold nanowire is induced for a short period of about 10?μs by applying a voltage pulse. A local temperature analysis and a controlled electromigration experiment in the presence of voltage pulses indicate successful control of this voltage-pulsed-induced electromigration. We also measured the current-voltage characteristics of the nanowire after the application of each single voltage pulse to investigate the stochastic behavior of electromigration. A pulse duration shorter than the thermal relaxation time of the nanowire would allow us to separately control the local temperature and driving force for electromigration.  相似文献   
56.
The formation mechanism of spinels on Al2O3 particles in the Al2O3/Al–1.0 mass% Mg2Si alloy composite material has been investigated by transmission electron microscopy (TEM) in order to determine the crystallographic orientation relationship. A thin sample of the Al2O3/Al–Mg–Si alloy composite material was obtained by the FIB method, and the orientation relationship between Al2O3 and MgAl2O4, which was formed on the surface of Al2O3 particles, was discovered by the TEM technique as follows:
At the interface between the Al2O3 and the matrix the MgAl2O4 (spinel) crystals had facets of {111} planes. Spinels were not grown as thin films, but as particles consisting of {111} planes. They grow towards both the matrix and the Al2O3 particles.  相似文献   
57.
A continuous stirred tank reactor was used for the dark hydrogen fermentation of cellulose by mixed microflora at hyper-thermophilic temperature (70 ± 1 °C) for 240 days. A total of twenty six batch experiments were conducted to investigate the effect of temperature on the activity of cellulosic-hydrogen producing bacteria. The results show that the system reached a steady state condition after 90 days. A stable hydrogen yield of 7.07 ± 0.23 mmol H2/g cellulose was maintained for 150 days with acetate, butyrate, ethanol and propionate as main soluble byproducts. Analysis of 16S rRNA sequences showed that the cellulolytic bacteria were close to Thermoanaerobacterium genus. The cellulosic-hydrogen producing bacteria were able to utilize the cellulose or glucose within a wide range of fermentation temperatures (45–80 °C) to produce hydrogen. The activation energy for cellulose and glucose were estimated at 133.2 and 117.7 kJ/mol, respectively.  相似文献   
58.
It is desirable for a container crane to operate smoothly and quickly. For this purpose, the control system of a container crane should be capable of antisway control for suppressing vibrations. A vision sensor system is often used to detect the sway angle. However, since a control system with a vision sensor has a delay time when determining the angle, it sometimes leads to deterioration of control performance owing to the delay time. In order to overcome this problem, this paper proposes a new antisway crane control system based on a dual‐state observer with sensor‐delay correction. However, because of nonlinear friction in the crane, the estimation accuracy achieved by using the observer is poor. To overcome this problem, this paper proposes a disturbance observer considering friction disturbance. The control performance and e?ectiveness of the proposed robust control system based on the estimated information are shown to be satisfactory by experimental results. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 184(3): 36–46, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22412  相似文献   
59.
The thermally stimulated current (TSC) technique has been used to investigate molecular relaxation in poly(ethylene terephthalate) (PET) films unstretched and biaxially stretched at 90 and 95 °C. Unstretched PET films show two peaks at 77 and 90 °C corresponding to α and ρ relaxation processes, respectively. The α relaxation is associated with the main glass transition of the material. The ρ peak with lower intensity is attributable to permanent dipoles. Both biaxially stretched samples show one TSC peak at 95 °C, supposed to correspond to ρ relaxation. The disappearance of the α peak, accompanied by the displacement of the ρ peak to higher temperature, is the result of the higher thermal stability of the permanent dipoles, which is strongly influenced by the stiffening of amorphous parts and the crystallization by stretching. In both stretched samples, the continuous distribution of pre-exponential factors over activation energies observed might correspond to a single relaxation mode. The kinematics of stretching PET has been discussed in terms of activation energy and temperature dependence of relaxation time. © 1999 Society of Chemical Industry  相似文献   
60.
After a series of investigations on the durable flame‐retardant finishes, it was thought to be important to study these durable flame‐retardant finished materials from the thermal analytical standpoint. Accordingly, cotton fabric was finished with N‐methylol dialkyl phosphonopropionamide (Pyrovatex C) by thermofixation and tetrakis (hydroxymethyl) phosphonium sulfate (THPS) precondensate by ammonia cure (Proban), as well as with THPS monomer by heat cure under various conditions, and subjected to the thermogravimetry (TG) to observe thermal degradation behaviors and obtain apparent activation energy (Ea). TG curves of Proban‐finished samples showed the largest shift to lower temperatures with a steep slope; thermofixed THPS‐finished sample gave a smaller shift with similar steep slope, whereas Pyrovatex‐finished samples exhibited a similar shift but with a gradual slope. Ea versus residual ratio curves led us to conclude that C N bond‐rich Proban polymer requires the highest Ea and decomposes with considerable rapidity, whereas ethylene‐bond‐rich Pyrovatex‐finished samples with melamine crosslinking decompose gradually with the lowest Ea. As for the relationship between flame retardance and Ea distribution in the process of thermal degradation, typical differences among the above three kinds of finished samples were found, which are compared and discussed. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 975–987, 1999  相似文献   
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