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1.
In this study, we investigated the activity of pre-sulfated 1%Pt–2%Sn/γ–Al2O3 on the catalytic abatement of the combustion emissions of three fuels: pure diesel E(0), pure bioethanol E(100) and bioethanol blended diesel containing 10% bioethanol E(10). The emissions generated, by each blend combustion, were conducted continuously to the catalyst sample. The catalytic activity was determined by following the evolution of the outflow emissions concentrations by FTIR gas spectroscopy as a function of the catalyst temperature. Results showed that the addition of bioethanol to diesel may be necessary to enhance the catalytic oxidation of diesel unburned hydrocarbons and particulate matter on pre-sulfated 1%Pt–2%Sn/γ–Al2O3.  相似文献   
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OBJECTIVES: This study examined the relation of hysterectomy and oophorectomy to heart disease risk factors. METHODS: Data were collected and analyzed for 1150 women aged 50 through 89. RESULTS: Of these women, 21.8% reported hysterectomy with bilateral oophorectomy; 22.1%, hysterectomy with ovarian conservation. Compared with women without hysterectomy, oophorectomized women, especially those 20 or more years postmenopause, had increased lipids, lipoproteins, glucose, and insulin; blood pressures were increased among current estrogen users. Women with hysterectomies with ovarian conservation had similar or more favorable risk factors than nonhysterectomized women. CONCLUSIONS: Bilateral oophorectomy, but not hysterectomy, may have long-term negative consequences for heart disease risk factors not totally ameliorated by estrogen use.  相似文献   
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Raman spectroscopy experiments on double-wall carbon nanotube and highly oriented pyrolytic graphite (HOPG) samples subjected to non-hydrostatic conditions have been conducted in anvil cells to study the effect of the pressure/stress on the bands assigned to defects. Typical diamond anvils used in high pressure experiments have been substituted by moissanite (6H-SiC) and sapphire (Al2O3) anvils to allow the observation of the D band (around 1350 cm−1) and the second-order Raman scattering without interference. We demonstrate that Raman experiments at high pressure provide unique information to probe the mechanical behaviour of carbon materials (CMs). We also show that this can be also a powerful technique to assign controversial spectral features such as those appearing in the second order region of the spectra of CMs. In HOPG samples we find that the D′/D band intensity ratio is independent of stress. The results indicate that an increase of non-hydrostatic stresses on HOPG generates graphitic domains with sizes around 20–30 nm when the sample is recovered to room conditions.  相似文献   
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Orphanin FQ or nociceptin (OFQ/N(1-17)) is a recently discovered peptide which, upon intracerebroventricular administration, reverses opioid-mediated analgesias. OFQ/N(1-17) terminals are located in the periaqueductal gray (PAG), a structure known to be involved in pain modulation, suggesting that the functional anti-opioid effects of OFQ/N(1-17) are mediated by PAG neurons. To test this, subsequent microinjections of morphine or kainic acid and OFQ/N(1-17) were made into the PAG of awake rats. Administration of OFQ/N(1-17) attenuated the tail flick inhibition produced by both morphine and kainic acid microinjection. OFQ/N(1-17) attenuation of antinociception produced by a neuroexcitant indicates that OFQ/N(1-17) reverses opioid antinociception by inhibiting PAG output neurons.  相似文献   
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A high quality biodiesel was produced from Mexican Jatropha curcas crude oil (JCCO) by a two step catalyzed process. The free fatty acids (FFA) were first esterified with methanol, catalyzed by a solid catalyst: SiO2 pretreated with HF. The catalyst showed a high number of Lewis acid surface sites, and no CO2 or H2O adsorption activity. This catalyst showed a high FFA esterification activity and high stability. After 30 esterification runs, the catalyst activity remained unchanged. During the second step, the triglycerides present in the JCCO were transesterified with methanol catalyzed by NaOH. The chromatographic analysis of the biodiesel obtained, revealed that the process proposed in this investigation led to a very high quality biodiesel, meeting the international requirements for its utilization as a fuel. The combustion gas emissions of the JCCO biodiesel were studied by FTIR spectroscopy using a laboratory combustor. These preliminary results showed low amounts of aromatic and sulfur containing compounds. However, halogenated compounds and dicyclopentadiene were also detected at the combustor exhaust.  相似文献   
7.
A revolution in molecular biological technology has allowed, for the first time, the study of pain at the level of the gene. The molecular genetic technique currently garnering the most interest is the use of transgenic mice that either overexpress, or do not express, presumably pain-related proteins. This paper reviews the findings of investigations in which a transgenic mouse has been assessed for nociceptive or analgesic sensitivity. As of this writing, 25 different kinds of mutant mice--lacking neurotrophins and their receptors, peripheral mediators of nociception and hyperalgesia, opioids and their receptors, non-opioid transmitter receptors, and intracellular molecules participating in signal transduction--have been produced and tested on behavioral assays of nociception. Results of these studies have been variously confirmatory, contradictory and enlightening compared to conventional investigations. The advantages and limitations of this approach to pain research are discussed.  相似文献   
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In the present article, antimony sulfide nanoparticles have been synthesized by pulsed laser ablation of an antimony sulfide pellet in distilled water and isopropyl alcohol. The target was irradiated by 1064 and 532 nm from a pulsed Nd:YAG laser operated at 10 Hz and pulse width of 10 ns at room temperature. Analysis of the morphology, crystalline phase and elemental composition were done using transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The optical band gap energies of these colloidal nanoparticles were evaluated from UV–Visible absorption spectra. It was observed that the morphology, size, and optical properties of the antimony sulfide nanoparticles depend on the wavelength of the laser and the liquid media.  相似文献   
10.
The behavior of flax fibers was investigated at temperatures of 80 °C, 200 °C, 215 °C, and 230 °C for a period of 60 min. First, thermogravimetric and colorimetric analyzes were carried out to characterize the impact of the temperature on the weight loss and the color of the fibers. Then, the release of volatile and odorous compounds from flax fibers was studied using both chemical and sensory approaches. Solid phase micro extraction was done to isolate the volatile organic compounds (VOCs) from the headspace of the sample while gas chromatography‐mass spectrometry (GC‐MS) and olfactometry (O) were used to determine the volatile and odorous compounds released at each temperature. About 24 VOCs were identified in the volatile fraction of flax fibers with a high occurrence of aliphatic aldehydes, phenols, and furans. Quantification by GC‐MS and by the aroma extract dilution analysis method was implemented. The results point to a critical temperature between 215 °C and 230 °C from which the odor of flax fibers becomes more intense, more complex, and with unpleasant features. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43497.  相似文献   
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