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21.
While novel technologies have tremendous competitive potential, they also involve certain risks. Maturity assessment analyzes how well a technological development can fulfill an expected task. The technology readiness level (TRL) has been considered to be one of the most promising approaches for addressing technological maturity. Nonetheless, its assessment requires opinions of the experts, which is costly and implies the risk of personal bias. To fill this gap, this paper presents a Bibliometric Method for Assessing Technological Maturity (BIMATEM). It is a repeatable framework that assesses maturity quantitatively. Our method is based on the assumption that each technology life cycle stage can be matched to technology records contained in scientific literature, patents, and news databases. The scientific papers and patent records of mature technologies display a logistic growth behavior, while news records follow a hype-type behavior. BIMATEM determines the maturity level by curve fitting technology records to these behaviors. To test our approach, BIMATEM was applied to additive manufacturing (AM) technologies. Our results revealed that material extrusion, material jetting, powder bed fusion and vat photopolymerization are the most mature AM technologies with TRL between 6 and 7, followed by directed energy deposition with TRL between 4 and 5, and binder jetting and sheet lamination, the least mature, with TRL between 1 and 2. BIMATEM can be used by competitive technology intelligence professionals, policymakers, and further decision makers whose main interests include assessing the risk of implementing new technologies. Future research can focus on testing the method with regard to altmetrics.  相似文献   
22.
Phaseolus vulgaris is a foodstuff that not only supplies nutrients, but also bioactive compounds with antioxidant capacity; however, bad post-harvest storage or processing can diminish the antioxidant capacity. In this work, the effect of storage under extreme conditions, of thermal processing and of fermentation on the content of phenolic compounds and their antioxidant capacity (AA) in beans of just harvested P. vulgaris were evaluated. Combination of temperatures of 30 and 50 °C and relative humidity of 11% and 80% for 150 days were evaluated. Extreme storage conditions drastically decreased the AA, demonstrating that post-harvest storage at low temperature and humidity preserves the antioxidant capacity of the beans. Regarding processing, cooking decreased the scavenging effect and the AA by 63.5% and 56.8%, while fermentation decreased them by only 14% and 22%, respectively. It was concluded that the loss of antioxidant capacity due to heating is less in fermented beans.  相似文献   
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24.
Variations in genes involved in DNA repair systems have been proposed as risk factors for the development of preeclampsia (PE). We conducted a case-control study to investigate the association of Human apurinic/apyrimidinic (AP) endonuclease (APEX1) Asp148Glu (rs1130409), Xeroderma Pigmentosum group D (XPD) Lys751Gln (rs13181), X-ray repair cross-complementing group 1 (XRCC) Arg399Gln (rs25487) and X-ray repair cross-complementing group 3 (XRCC3) Thr241Met (rs861539) polymorphisms with PE in a Mexican population. Samples of 202 cases and 350 controls were genotyped using RTPCR. Association analyses based on a χ2 test and binary logistic regression were performed to determine the odds ratio (OR) and a 95% confidence interval (95% CI) for each polymorphism. The allelic frequencies of APEX1 Asp148Glu polymorphism showed statistical significant differences between preeclamptic and normal women (p = 0.036). Although neither of the polymorphisms proved to be a risk factor for the disease, the APEX1 Asp148Glu polymorphism showed a tendency of association (OR: 1.74, 95% CI = 0.96–3.14) and a significant trend (p for trend = 0.048). A subgroup analyses revealed differences in the allelic frequencies of APEX1 Asp148Glu polymorphism between women with mild preeclampsia and severe preeclampsia (p = 0.035). In conclusion, our results reveal no association between XPD Lys751Gln, XRCC Arg399Gln and XRCC3 Thr241Met polymorphisms and the risk of PE in a Mexican mestizo population; however, the results in the APEX1 Asp148Glu polymorphism suggest the need for future studies using a larger sample size.  相似文献   
25.
Plasma nitriding behavior of Fe-Cr alloys has been studied at temperatures in the range of 773–873 K in order to provide basic knowledge for microstructure design of nitrided layers and to improve the wear resistance. In the nitriding temperature of 773 K, typical microstructure of nitrided layers was observed as reported elsewhere. However, anormal microstructure of nitrided layers was observed under a nitriding condition, at 873 K for 176.4 ks (49 h). In Fe-13Cr alloy, nitrided layer showed stripe-pattern, each sub-layer of which has different chromium content. Nitrided layer hardness increased gradually from the specimen surface to the nitriding front before dropping drastically to the same level as matrix hardness. The stripe-pattern was also observed for Fe-3Cr alloy at the vicinity of nitriding front for the same nitriding conditions. On the other hand, nitrided layers in Fe-8Cr and Fe-19Cr alloys are composed from different sub-layers, containing different concentration of chromium. These phenomena cannot be explained only by nitrogen diffusion process during the nitriding.  相似文献   
26.
In this article we report the removal of Pb, Ni and Cu using a hydrogel made with hydroxypropyl cellulose (HPC) and polyacrylamide (PAAm). The hydrogel successfully removed those metals, as shown by the results of atomic absorption spectroscopy; the polymer removed 53% of Pb, 52% of Ni and 51% of Cu. Different pHs were tried for these polymers. The highest metal removal was found at 40°C. The adsorption kinetics fitted Langmuir and Freundlich isotherms. Metal particles were detected on the hydrogel with electron microscopy and energy–dispersive X–ray spectroscpy, confirming that the gel removed the metals from the testing solutions. This polymer is a good option for treating wastewater and industrial waters as it removes metals and is composed of nontoxic materials. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43285.  相似文献   
27.
We studied the use of three biocompatible materials obtained by plasma polymerization of pyrrole (PPy), pyrrole doped with iodine (PPy/I) and a copolymer formed with pyrrole and polyethylene glycol (PPy/PEG), implanted, separately, after a complete spinal cord transection in rats. Motor function assessed with the BBB scale and somatosensory evoked potentials (SEPs) in the implanted rats were studied. Results showed that the highest motor recovery was obtained in rats with PPy/I implants. They also showed a significant reduction in the latency of SEPs. Histological analyses showed no signs of implant rejection; on the contrary, implants based on PPy improved the SEPs conduction and motor function after lesion.  相似文献   
28.
The purpose of this study was to investigate the effects of Bioglass 45S5® and Biosilicate®, on bone defects inflicted on the tibia of rats. Fifty male Wistar rats were used in this study, and divided into five groups, including a control group, to test Biosilicate® and Bioglass® materials of two different particle sizes (180–212 μm or 300–355 μm). All animals were sacrificed 15 days after surgery. No significant differences (P > 0.05) were found when values for Maximal load, Energy Absorption and Structural Stiffness were compared among the groups. Histopathological evaluation revealed osteogenic activity in the bone defect for the control group. Nevertheless, it seems that the amount of fully formed bone was higher in specimens treated with Biosilicate® (granulometry 300–355 μm) when compared to the control group. The same picture occurred regarding Biosilicate® with granulometry 180–212 μm. Morphometric findings for bone area results (%) showed no statistically significant differences (P > 0.05) among the groups. Taken together, such findings suggest that, Biosilicate® exerts more osteogenic activity when compared to Bioglass® under subjective histopathological analysis.  相似文献   
29.
Dry beans such as Phaseolus vulgaris are an important source of nutrients, especially in developing countries. However, their consumption is limited by the flatulence problem, which occurs in the gut after their ingestion, owing to the presence of highly fermentable compounds, such as -galactosides, soluble dietary fibre, and resistant starch. It has been shown that natural fermentation reduces the content of these compounds by about 90%. In the present work, the effects of the consumption of unfermented and fermented beans (P. vulgaris) on the bowel habits (frequency and faecal volume) and on the main adverse intestinal symptoms usually associated with bean consumption were compared. This study was carried out for 28 days with ten women, whose age ranged between 25 and 40 years, eating 45 g of fermented-cooked and cooked beans for 7 days, with a 2-week break between the experimental periods. A sensorial evaluation with 51 panellists was performed revealing that 56% of the panel gave the fermented samples a score between 6 and 9, corresponding to slightly like it and really like it, respectively. The consumption of fermented beans significantly decreased the flatulence problem by 56.1%, the intestinal noises by 48% and the nausea by 80%. Abdominal bloating was reduced by 11%. It was concluded that the fermented and cooked beans were palatable and that the process could decrease the flatulence problem that is usually caused by the consumption of P. vulgaris by humans.  相似文献   
30.
The nutrients, non‐nutritional components and bioactive compounds, as well as the antioxidant capacity of raw, cooked, tray and drum‐dried Phaseolus lunatus have been quantified. Likewise, the minerals, soluble carbohydrates, total polyphenols and tannins in the soaking and cooking waters were quantified. In addition, the functional properties such as the water and oil absorption indexes and the emulsifying and the foaming capacities were studied. The protein content of the raw beans was 24.98% and decreased, like calcium, magnesium and potassium, with the soaking and cooking processes; these losses are found in the soaking and cooking waters. Drum drying decreased anti‐nutritional factors like trypsin inhibitors (66.09%) and cyanhydric acid (50.36%). Similarly, soluble fiber, available starch, total starch, and soluble sugars diminished, while total and insoluble fiber and resistant starch increased. The content of total polyphenols, tannins and antioxidant capacity decreased with thermal processing, being drum drying the process that least diminished antioxidant capacity. Likewise, the water absorption index was increased by 85% and 161.5% with processing. It was shown that P. lunatus is an important source of nutrients and can be consumed in whole bean form or used as a functional ingredient to be added in the development of new products. Copyright © 2007 Society of Chemical Industry  相似文献   
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