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111.
Children exposed to alcohol prenatally may suffer from severe brain damage, expressed as a variety of behavioral problems, including hyperactivity and learning deficits. There is a critical need to identify effective treatments for fetal alcohol effects. Physical exercise enhances cognitive ability and increases neurogenesis in the hippocampus, a brain area important for learning and memory. Thus, the present study examined whether physical exercise might reduce the severity of alcohol-induced behavioral alterations. Sprague-Dawley rats were intubated with 5.25 g/kg/day ethanol during the third trimester equivalent (postnatal days [PDs] 4-9). Intubated sham control and nontreated controls were included. From PD 21 to PD 51, half of the subjects were given access to running wheels. On PD 52, subjects were tested on the Morris water maze, and on PD 60, open field activity levels were measured. Morris maze performance was significantly impaired among ethanol-exposed subjects; exercise significantly improved performance of all groups. Similarly, ethanol-exposed subjects were overactive in the open field, an effect attenuated with exercise. In sum, these data suggest that exercise may increase neuronal plasticity not only in controls, but also in subjects exposed to alcohol during development. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
112.
The purpose of the present research was to clarify the effect of docosahexaenoic acid (DHA) intake on behavior and plasma catecholamines (CA). In Study 1, 42 students took either DHA-rich oil capsules containing 1.5–1.8 g DHA/d or control oil capsules containing 97% soybean oil plus 3% of another fish oil for 3 mon in a double-blind fashion. They took a psychological test (PF Study) at the start and end of the study. This study started at the end of summer vacation and ended just before the final exams. In the control group, external aggression (aggression against others) in PF Study was significantly increased at the end of the study as compared with that measured at the start (+8.9%), whereas it was not significantly changed in the DHA group (?1.0%). In a similar double-blind study (Study 2), we measured external aggression under nonstressful conditions. External aggression slightly decreased in the control group, whereas there were no significant changes in the DHA group. In Study 3 with 14 students, plasma CA were measured at the start and end of capsule administration period of 2 mon. Subjects were under continuous stress of the final exams that lasted throughout the whole study period. The ratio of plasma epinephrine to norepinephrine concentrations was significantly increased in the DHA group (78%), whereas it stayed at the same level in the control group. In Study 4, mice were fed either DHA-deficient diet or -sufficient diet for 4 wk, and their rearing frequency (an anxiety index) was measured. In the DHA-sufficient group, the rearing frequency was significantly less than in the other group. These effects of DHA intake may be applied to people in an attempt to ameliorate stress-related diseases.  相似文献   
113.
Some tetracycline (TC) antibiotics, including TC and anhydrotetracycline, have been found to enhance specific binding of low density lipoprotein (LDL) to both LDL receptor-positive and-negative cells at relatively higher concentrations. When incubated at 37°C, the ability of LDL receptor-negative human fibroblasts to bind 125I-LDL was increased from<2 to 45 ng/mg by 170 μM TC. In normal human fibroblasts and Hep G2 cells, 125I-LDL binding was elevated 1.4- to 2-fold by 113 μM TC. The 125I-LDL binding in the presence of TC was diminished by both heparin and EDTA. The enhancement by TC was not observed when 125I-LDL binding was assayed at 4°C. TC enhanced LDL binding to paraformaldehyde-fixed Hep G2 cells, excluding LDL receptor induction in the mechanism. These results demonstrated that TC enhanced cellular LDL binding through a process not involving functional LDL receptors.  相似文献   
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115.
A method of improving soft clayey deposit by combining cap-drain (CPVD) with vacuum pressure is described. The method uses a surface or subsurface soil layer as a sealing layer with no need to place an air-tightening sheet on the ground surface. It is explained that the method has advantages for the following situations: (a) a higher air/water permeability layer at ground surface and (b) combining vacuum pressure with embankment load. A case history of consolidating a reclaimed clayey deposit by combining CPVD with vacuum pressure is analyzed and discussed. The site was in an under-consolidated state before starting the project. It is shown that the method is effective, and the method proposed by Chai et al. [Ground deformation induced by vacuum consolidation. Journal of Geotechnical and Geoenvironmental Engineering, ASCE 131(12), 1552–1561] for calculating the vacuum-pressure-induced ground deformation is useful for the design of the vacuum consolidation project. The back-calculation shows that for this under-consolidated deposit, vacuum pressure caused plane strain type isotropic deformation near the ground surface.  相似文献   
116.
An AlxGa1-xSb avalanche photodiode (APD) with an Al composition of 0.05 has been fabricated and tested. The measured gain-bandwidth (GB) product of the highly doped diode is 90 GHz. Such a large GB product has never been previously achieved by any APD materials sensitive in the long-wavelength region. This suggests the advantage of the AlxGa1-xSb material system for very high-speed operation  相似文献   
117.
The carrier transport properties in metal-oxide (top oxide) nitride-oxide (tunnel oxide) silicon (MONOS) memory structures have been investigated in steady-state conditions under negative gate bias voltage. Carriers were separated into holes and electrons utilizing an induced junction of the p-channel MONOS transistors. Two-carrier transport is confirmed in the structure at negative gate polarity. It is found that the relatively thick top oxide acts as a potential barrier to the holes injected from the Si into the thin nitride. It is also found that a portion of the electrons injected from the gate at negative gate polarity recombine with the holes injected from the Si even in such a thin nitride and/or at the top-oxide/nitride interface  相似文献   
118.
Now that environmental awareness is enhanced on a global basis, great hopes are placed on the expanded use of hydrogen stations and fuel-cell vehicles (FCVs) that economize hydrogen energy. Hydrogen stations must be safe and secure because they store large quantities of hydrogen under higher pressure than the hydrogen actually consumed by FCVs. Thus, multiple safety measures are taken to ensure that hydrogen does not leak from the stations. Furthermore, in the unlikely event of leakage, the damage needs to be kept on an allowable level. For this reason, it is necessary to understand the behavior of hydrogen gas leaking from the stations.  相似文献   
119.
1,3-Dipalmitoyl-2-oleoyl-sn-glycerol (POP) and 1,2-dioleoyl-3-palmitoyl-rac-glycerol (OOP) are two major molecular species that account for roughly half of the total triacylglycerols in palm oil. The binary phase behavior of a POP/OOP mixture plays an important role in the crystallization of palm oil. We conducted thermodynamic and kinetic studies of OOP and its mixtures with POP using differential scanning calorimetry and X-ray diffraction with a conventional generator and synchrotron radiation. We found that OOP has two polymorphs, α as a metastable form and β′ as the most stable form, and that the two forms are stacked in a triple-chain-length structure. The POP/OOP mixtures exhibited immiscible eutectic natures in both their metastable and their most stable states, in contrast to POP/1,2-dipalmitoyl-3-oleoyl-rac-glycerol and POP/1,3-dioleoyl-2-palmitoyl-sn-glycerol mixtures, in which molecular compounds of a double-chain-length structure were formed. A time-resolved synchrotron radiation X-ray diffraction study undertaken during the cooling and heating processes indicated that the α and β′ forms of the POP and OOP fractions crystallized and melted in separate manners, and that crystallization of the β′ form and the polymorphic transformation from α to β′ of POP and OOP are promoted in the presence of another component. The absence of molecular compound crystals in the binary mixtures of POP/OOP is explained by taking into account the molecular interactions of acyl chain packing, glycerol conformation, and methyl end stacking, among which glycerol conformation appeared to be most influential.  相似文献   
120.
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