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161.
Palyno‐anatomical study of monocots taxa using Light and Scanning Electron Microscopy (SEM) was first time conducted with a view to evaluating their taxonomic significance. Studied plants were collected from different eco‐climatic zones of Pakistan ranges from tropical, sub‐tropical, and moist habitats. The aim of this study is to use palyno‐anatomical features for the correct identification, systematic comparison, and investigation to elucidate the taxonomic significance of these features, which are useful to taxonomists for identifying monocot taxa. A signification variation was observed in quantitative and qualitative characters by using the standard protocol of light microscopy (LM) and SEM. Epidermal cell length varied from maximum in Allium griffthianum (480 ± 35.9) μm at the adaxial surface to minimum in Canna indica (33.6 ± 8.53) μm on abaxial surface. Maximum exine thickness was observed in Canna indica (4.46) μm and minimum in Allium grifthianum (0.8) μm. Variation was observed in shape and exine ornamentation of the pollen, shape of the epidermal cell, number, size, and type of stomata, guard cell shape, and anticlinal wall pattern. Based on these palyno‐anatomical features a taxonomic key was developed, which help in the discrimination of studied taxa. In conclusion, LM and SEM pollen and epidermal morphology is explanatory, significant, and can be of special interest for the plant taxonomist in the correct identification of monocots taxa.  相似文献   
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163.
Olive oil with rosemary leaves by microwave assisted infusion (MAI) as an alternative to conventional infusion (CI) was evaluated. Microwave heating was applied to the mixture in order to accelerate diffusion of the rosemary volatile compounds into the olive oil. The volatile components of the aromatized oils were quantified by HS‐SPME/GC–MS, as well as several quality indexes such as free fatty acids (FFA), peroxide value (PV), specific coefficients of extinction, chlorophyll and carotenoid content, and color assessment. Fatty acid profiles of the oils aromatized by MAI were compared to those produced by CI. Results showed that the infusion time is reduced from 12 h to 10 min when utilizing MAI in place of CI. MAI treatment caused a slight increase in FFA levels, and specific extinction coefficient indices (K232 and K270). PV during MAI remained unchanged for the first 3 min, after which there was an observable increase. All physico‐chemical values were found to be well below the maximum permitted limits. The MAI treatment reduced chlorophyll and carotenoid levels during the final step of aromatization, thus affecting final color. The MAI aromatized oil was characterized by its clear green color (L*, a*, b* parameters). Fatty acid analysis showed that MAI slightly changed the fatty acid composition of the olive oil. This study indicates that MAI appears to be a viable and rapid method to flavor olive oil with rosemary leaves.  相似文献   
164.
Hydrophobic fibrous slippery liquid-infused porous surfaces (SLIPS) were fabricated by electrospinning polydimethylsiloxane (PDMS) and polystyrene (PS) as a carrier polymer on plasma-treated polyethylene (PE) and polyurethane (PU) substrates. Subsequent infusion of blackseed oil (BSO) into the porous structures was applied for the preparation of the SLIPS. SLIPS with infused lubricants can act as a repellency layer and play an important role in the prevention of biofilm formation. The effect of polymer solutions used in the electrospinning process was investigated to obtain well-defined hydrophobic fibrous structures. The surface properties were analyzed through various optical, macroscopic and spectroscopic techniques. A comprehensive investigation of the surface chemistry, surface morphology/topography, and mechanical properties was carried out on selected samples at optimized conditions. The electrospun fibers prepared using a mixture of PDMS/PS in the ratio of 1:1:10 (g/g/mL) using tetrahydrofuran (THF) solvent showed the best results in terms of fiber uniformity. The subsequent infusion of BSO into the fabricated PDMS/PS fiber mats exhibited slippery behavior regarding water droplets. Moreover, prepared SLIPS exhibited antibacterial activity against Staphylococcus aureus and Escherichia coli bacterium strains.  相似文献   
165.
Female reproduction depends on the metabolic status, especially during the period of folliculogenesis. Even though it is believed that melatonin can improve oocyte competence, there is still limited knowledge of how it can modulate metabolic processes during folliculogenesis and which signaling pathways are involved in regulating gene expression. To investigate the effects of melatonin on metabolic signals during the antral stage of follicular development, human granulosa-like tumor cells (KGN) were treated with melatonin or forskolin, and gene expression was analyzed with RNA-seq technology. Following appropriate normalization and the application of a fold change cut-off of 1.5 (FC 1.5, p ≤ 0.05), 1009 and 922 genes were identified as differentially expressed in response to melatonin and forskolin, respectively. Analysis of major upstream regulators suggested that melatonin may activate PKB/mTOR signaling pathways to program the metabolism of KGN cells to support slower growth and differentiation and to prevent follicular atresia. Similarly, PKA activation through stimulation of cAMP synthesis with FSK seemed to exert the same effects as melatonin in reducing follicular growth and regulating differentiation. This study suggests that melatonin may act through PKA and PKB simultaneously in human granulosa cells to prevent follicular atresia and early luteinization at the antral stage.  相似文献   
166.
BACKGROUND: The development of low-cost, high-protein food supplements for weaning infants from local and readily available raw materials is a constant challenge for developing countries. OBJECTIVE: To formulate, develop, and assess the nutritive value, acceptability, and keeping quality of sorghum-based staple dried flakes as instant weaning foods. METHODS: Weaning blends composed of 42% sorghum supplemented with 20% legumes, 10% oil seeds, and 28% additives (sugar, oil, skim milk powder, and vanillin) were prepared according to FAO/WHO/UNU recommendations and processed in a twin-roller drum dryer. The effects of fermentation and of the addition of malt on the nutritive value and functional properties of the blends were investigated. RESULTS: The blends were found to contain 16.6% to 19.3% protein, 68.7% to 72.7% carbohydrate, 0.9% to 1.3% fiber, and 405.8 to 413.2 kcal of energy per 100 g. The iron content of the blends ranged from 5.3 to 9.1 mg/100 g, and the calcium content ranged from 150 to 220 mg/100 g. All blends reconstituted well and formed a soft paste when stirred with hot or cold water. The water-holding capacity, wettability, and bulk density were within the ranges of corresponding values of commercial weaning foods. Sensory attributes, viscosity values, and in vitro digestibility varied among the blends, whereas lysing content improved considerably (p < or = .05) for all blends. All blends had similar keeping quality, with no signs of spoilage or development of off-flavors or colors after 10 months of storage. Most blends remained free of aflatoxins. CONCLUSIONS: Legumes and oil seeds can be effectively used in sorghum-based weaning foods as an acceptable protein and mineral supplement.  相似文献   
167.
Oxidative stress is implicated in the pathogenesis of diabetic complications, and can be increased by diet like white rice (WR). Though brown rice (BR) and germinated brown rice (GBR) have high antioxidant potentials as a result of their bioactive compounds, reports of their effects on oxidative stress-related conditions such as type 2 diabetes are lacking. We hypothesized therefore that if BR and GBR were to improve antioxidant status, they would be better for rice consuming populations instead of the commonly consumed WR that is known to promote oxidative stress. This will then provide further reasons why less consumption of WR should be encouraged. We studied the effects of GBR on antioxidant status in type 2 diabetic rats, induced using a high-fat diet and streptozotocin injection, and also evaluated the effects of WR, BR and GBR on catalase and superoxide dismutase genes. As dietary components, BR and GBR improved glycemia and kidney hydroxyl radical scavenging activities, and prevented the deterioration of total antioxidant status in type 2 diabetic rats. Similarly, GBR preserved liver enzymes, as well as serum creatinine. There seem to be evidence that upregulation of superoxide dismutase gene may likely be an underlying mechanism for antioxidant effects of BR and GBR. Our results provide insight into the effects of different rice types on antioxidant status in type 2 diabetes. The results also suggest that WR consumption, contrary to BR and GBR, may worsen antioxidant status that may lead to more damage by free radicals. From the data so far, the antioxidant effects of BR and GBR are worth studying further especially on a long term to determine their effects on development of oxidative stress-related problems, which WR consumption predisposes to.  相似文献   
168.
Methylphenidate (MPH) is among the main drugs prescribed to treat patients with attention-deficit and hyperactivity disease (ADHD). MPH blocks both the norepinephrine and dopamine reuptake transporters (NET and DAT, respectively). Our study was aimed at further understanding the mechanisms by which MPH could modulate neurotransmitter efflux, using ex vivo radiolabelled neurotransmitter assays isolated from rats. Here, we observed significant dopamine and norepinephrine efflux from the prefrontal cortex (PFC) after MPH (100 µM) exposure. Efflux was mediated by both dopamine and norepinephrine terminals. In the striatum, MPH (100 µM) triggered dopamine efflux through both sodium- and vesicular-dependent mechanisms. Chronic MPH exposure (4 mg/kg/day/animal, voluntary oral intake) for 15 days, followed by a 28-day washout period, increased the firing rate of PFC pyramidal neurons, assessed by in vivo extracellular single-cell electrophysiological recordings, without altering the responses to locally applied NMDA, via micro-iontophoresis. Furthermore, chronic MPH treatment resulted in decreased efficiency of extracellular dopamine to modulate NMDA-induced firing activities of medium spiny neurons in the striatum, together with lower MPH-induced (100 µM) dopamine outflow, suggesting desensitization to both dopamine and MPH in striatal regions. These results indicate that MPH can modulate neurotransmitter efflux in brain regions enriched with dopamine and/or norepinephrine terminals. Further, long-lasting alterations of striatal and prefrontal neurotransmission were observed, even after extensive washout periods. Further studies will be needed to understand the clinical implications of these findings.  相似文献   
169.
Aurivillius Na0.5Bi4.5Ti4O15 and Bi4Ti3O12 compounds were synthesized via solid-state reaction tech-nique.X-ray powder diffraction study confirmed monophasic fo...  相似文献   
170.
In many fields, like aspect category detection (ACD) in aspect-based sentiment analysis, it is necessary to label each instance with more than one label at the same time. This study tackles the multilabel classification problem in the ACD task for the Arabic language. For this purpose, we used Arabic hotel reviews from the SemEval-2016 dataset, comprising 13,113 annotated tuples provided for training (10,509) and testing (2,604). To extract valuable information, we first propose specific data preprocessing. Then, we suggest using the dynamic weighted loss function and a data augmentation method to fix the problem with this dataset's imbalance. Using two possible approaches, we develop new ways to find different categories of things in a review sentence. The first is based on classifier chains using machine learning models. The second is based on transfer learning using pretrained AraBERT fine-tuning for contextual representation. Our findings show that both approaches outperformed the related works for ACD on the Arabic SemEval-2016. Moreover, we observed that AraBERT fine-tuning performed much better and achieved a promising F 1 $$ {F}_1 $$ -score of 68 . 02 % $$ 68.02\% $$ .  相似文献   
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