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41.
42.
We evaluated the mechanisms underlying the oxytocin (OXT)-induced analgesic effect on orofacial neuropathic pain following infraorbital nerve injury (IONI). IONI was established through tight ligation of one-third of the infraorbital nerve thickness. Subsequently, the head withdrawal threshold for mechanical stimulation (MHWT) of the whisker pad skin was measured using a von Frey filament. Trigeminal ganglion (TG) neurons innervating the whisker pad skin were identified using a retrograde labeling technique. OXT receptor-immunoreactive (IR), transient receptor potential vanilloid 1 (TRPV1)-IR, and TRPV4-IR TG neurons innervating the whisker pad skin were examined on post-IONI day 5. The MHWT remarkably decreased from post-IONI day 1 onward. OXT application to the nerve-injured site attenuated the decrease in MHWT from day 5 onward. TRPV1 or TRPV4 antagonism significantly suppressed the decrement of MHWT following IONI. OXT receptors were expressed in the uninjured and Fluoro-Gold (FG)-labeled TG neurons. Furthermore, there was an increase in the number of FG-labeled TRPV1-IR and TRPV4-IR TG neurons, which was inhibited by administering OXT. This inhibition was suppressed by co-administration with an OXT receptor antagonist. These findings suggest that OXT application inhibits the increase in TRPV1-IR and TRPV4-IR TG neurons innervating the whisker pad skin, which attenuates post-IONI orofacial mechanical allodynia.  相似文献   
43.

Abstract  

The Pd phosphine complex catalysts immobilized onto polyethylene glycol (PEG)-modified silica were prepared in order to clarify the effect of the PEG modification on the Suzuki–Miyaura coupling reaction in organic solvents. For the reaction of ethyl p-bromobenzoate and phenylboronic acid in the presence of potassium carbonate in toluene, the PEG-modified silica-immobilized Pd catalysts exhibited much higher activities than the catalysts without PEG modification.  相似文献   
44.
ABSTRACT

Ammonium nitrate (AN) propellants have attracted attention because of their low cost and ecofriendliness despite certain major disadvantages such as low burning rate, poor ignitability, low energy, and volume change due to phase transition of AN. The addition of nitramine to AN propellants is one of the approaches to overcome these disadvantages. However, AN/nitramine propellants are characterized by easy initiation, high sensitivity, and high detonation velocity because of the high energy of nitramine. The detonation properties of AN/nitramine propellants were investigated in this study. It was observed that the AN/nitramine propellant required a booster to detonate the propellants, as detonation did not occur while using only a commercial electric blasting cap. It was further observed that the detonation velocity (D) increased linearly as the mass of nitramine per unit propellant volume was increased, and AN had a negligible effect on the detonation properties. An approximate equation was derived from the relationship between D and the mass per unit propellant volume of nitramine. The dominant factors that can be used to estimate the detonation/no-detonation boundaries of the propellants were identified, and the experimental boundary equations were determined using these factors.  相似文献   
45.
Copper removal from carbon-saturated molten iron to Al2S3-FeS flux was experimentally investigated in the temperature range from 1473 to 1573 K. The maximum copper distribution ratio between the Al2S3-FeS flux and the ferrous alloy was about 28 at the composition where the molar ratio of Al to Fe in the flux was around 2. The distribution ratio was no less than 25 as long as the copper content of the flux was less than 10 mass pct. The sulfur content in the ferrous alloy in equilibrium with the Al2S3-FeS flux was higher than that obtained by using Na2S-FeS flux, and it was concluded that the high copper distribution ratio of the Al2S3-FeS flux was brought about by the high activity coefficient of FeS in the flux. In experiments for recovering copper from the flux, copper in Al2S3-FeS-Cu2S flux was reduced by metallic aluminum at 1473 K. The FeS in the flux was primarily reduced and, after that, the copper was recovered in the form of Cu-Al-Fe alloy. The residual copper content in the flux could be decreased to less than 1 mass pct when the aluminum content in the alloy was higher than 40 mass pct. A process for copper removal from molten iron is proposed, which uses successive contacts between the Al2S3-FeS flux and molten iron at several stages with counterflow operation. It is suggested that 1 mass pct Cu in molten iron can be reduced to approximately 0.1 mass pct Cu using 100 kg flux/ton iron; the amount of aluminum required for the iterative use of the flux is about 10 kg/ton iron. By the recycling use of this Al2S3-FeS flux, it is suggested that copper removal from molten iron using the sulfide flux can be more effective.  相似文献   
46.
A new photochromic ZrO2 precursor solution was prepared using zirconium tetra-n-butoxide, 4-(phenylazo)benzoic acid and ethyleneglycol monomethylether. The density functional theory (DFT) calculation has identified that the structure of the synthesized precursor molecule changed by UV irradiation. Four types of thin films were prepared using the ZrO2 precursor solution with and without UV irradiation and applying an electric field. It was found that the surface morphology of thin films changed by applying UV irradiation to the precursor solution and an electric field.  相似文献   
47.
An innovative plutonium burner concept based on high temperature gas cooled reactor (HTGR) technology, “Clean Burn”, is proposed by Japan Atomic Energy Agency (JAEA). That is expected to be as an effective and safe method to consume surplus plutonium accumulated in Japan. A similar concept proposed by General Atomics (GA), Deep Burn, cannot be introduced to Japan because of its adopting highly enriched plutonium, which shall infringe on a Japanese nuclear nonproliferation policy according to Japan–US reprocessing negotiation. The Clean Burn concept can avoid this problem by employing an inert matrix fuel (IMF) and a tightly coupled fuel reprocessing and fabrication plants. Both features make it impossible to extract plutonium alone out of the fabrication process and its outcomes. As a result, the Clean Burn can use surplus plutonium as a fuel without mixing it with uranium matrix. Thus, surplus plutonium alone will be incinerated effectively, while generation of plutonium from the uranium matrix is avoided. High neutronic performance, i.e., achievement of burn-up of about 500 GWd/t and consumption ratio of plutonium-239 reaching to about 95%, is also assessed. Furthermore, reactivity defect caused by the inert matrix is found to be negligible. It is concluded that the Clean Burn concept is a useful option to incinerate plutonium with high proliferation resistance.  相似文献   
48.
49.
Demand for aseptically steamed rice products has been increasing rapidly in Japan over the past 10 years. In our previous study, we showed that proteolytic Clostridium botulinum produce toxins in steamed rice products packaged under a modified atmosphere of < or =0.3% oxygen. In the present study, we examined the effect of pH to control botulism risk in steamed rice products packaged under modified atmosphere (5% CO2 and 95% N2 as the balance) with the inclusion of a deoxidant pack to produce an oxygen concentration of < or =0.3%. A mixture of 10 strains of proteolytic C. botulinum (5 type A strains and 5 type B strains) was inoculated into steamed rice products at pH values between 4.6 and 6.8 prior to packaging. All samples were stored at 30 degrees C for 24 weeks. Samples at higher pH showed earlier starts of neurotoxin production. Neurotoxin was detected after 2 weeks of incubation in samples at pH 5.4 or above, whereas it took 4 weeks for the toxin to be detected in samples at pH 5.2 to 5.3 and 12 weeks in samples at pH 5.0 to 5.1. In samples at pH 4.9 or below, no toxin was detected during the experimental period. Apparent sample spoilage did not occur before C. botulinum produced neurotoxin in most of the samples. Based on these results, we conclude that aseptically steamed rice products must be packaged at pH 4.9 or below under modified atmosphere containing < or =0.3% oxygen, with the inclusion of a deoxidant pack.  相似文献   
50.
Experimental results are presented on the changes in mechanical properties of HASTELLOY X* after being used in the liner tube of HENDEL hot gas duct under high temperature helium gas for about 6000 hours. In both room and elevated-temperature tensile tests, 0.2 pct proof stress and total elongation were significantly decreased after exposure in high temperature helium. Room-temperature impact toughness of the exposed specimens exhibited a much lower absorbed energy (about 5.0 × 106 J/m2) than that of unexposed specimens (about 1.5 × 106 J/m2). The fracture modes of tensile test specimens were more closely correlated with the test temperature than with the long-time exposure; however, long-time exposure is more affected by the tensile strength of HASTELLOY X than the test temperature. Moreover, “downstream effect” for the carbide precipitation reaction occurred in the liner tube of the HENDEL hot gas duct. HASTELLOY is a trademark of Cabot Corporation.  相似文献   
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