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441.
The essential fatty acid alpha-linolenic acid (ALA) is present in high amounts in oils such as flaxseed, soy, hemp, rapeseed, chia, and perilla, while stearidonic acid is abundant in echium oil. ALA is metabolized to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) by desaturases and elongases in humans. The conversion of ALA to EPA and DHA is limited, and these long-chain n−3 polyunsaturated fatty acids (PUFAs) are mainly provided from dietary sources (fish and seafood). This review provides an overview of studies that explored the effects of dietary supplementation with ALA in obesity and related diseases. The obesity-associated changes of desaturase and elongase activities are summarized, as they could influence the metabolic conversion of ALA. Generally, supplementation with ALA or ALA-rich oils leads to an increase in EPA levels and has no effect on DHA or omega-3 index. According to the literature data, stearidonic acid could enhance conversion of ALA to long-chain n−3 PUFA in obesity. Recent studies confirm that EPA and DHA intake should be considered as a primary dietary treatment strategy for improving the omega-3 index in obesity and related diseases.  相似文献   
442.
The spread of organic pollutants in water spoils the environment, and among the best-known sorbents for removing organic compounds are carbonaceous materials. Sunflower seed waste (SFSW) was employed as a green and low-cost precursor to prepare carbon nanoparticles (CNPs) via pyrolysis, followed by a ball-milling process. The CNPs were treated with a nitric–sulfuric acid mixture (1:1) at 100 °C. The scanning electron microscopy (SEM) showed a particle size range of 38 to 45 nm, and the Brunauer–Emmett–Teller (BET) surface area was 162.9 m2 g−1. The elemental analysis was performed using energy-dispersive X-ray spectroscopy, and the functional groups on the CNPs were examined with Fourier transform infrared spectroscopy. Additionally, an X-ray diffractometer was employed to test the phase crystallinity of the prepared CNPs. The fabricated CNPs were used to adsorb ciprofloxacin (CFXN) and malachite green (MLG) from water. The experimentally obtained adsorption capacities for CFXN and MLG were 103.6 and 182.4 mg g−1, respectively. The kinetic investigation implied that the adsorption of both pollutants fitted the pseudo-first-order model, and the intraparticle diffusion step controlled the process. The equilibrium findings for CFXN and MLG sorption on the CNPs followed the Langmuir and the Fredulich isotherm models, respectively. It was concluded that both pollutants spontaneously adsorbed on the CNPs, with physisorption being the likely mechanism. Additionally, the FTIR analysis of the adsorbed CFXN showed the disappearance of some functional groups, suggesting a chemisorption contribution. The CNPs showed an excellent performance in removing CFXN and MLG from groundwater and seawater samples and possessed consistent efficiency during the recycle–reuse study. The application of CNPs to treat synthetically contaminated natural water samples indicated the complete remediation of polluted water using the ball-mill-fabricated CNPs.  相似文献   
443.
芹菜籽香气成分研究   总被引:8,自引:0,他引:8  
采用固相微萃取法萃取黑龙江产芹菜籽香气成分,然后用GC—MS进行成分分析,并与水蒸气蒸馏法获得的精油成分进行比较.用CAR on PDMS萃取柱进行顶空固相微萃取时,共检测出26种成分,鉴定出占总成份89.650%的20种成分,主要成分为柠檬烯(35.980%),β-月桂烯(20.500%),β-蛇床烯(16.160%),正戊基苯(5.295%),β-蒎烯(3.412%),α-蛇床烯(3.293%).水蒸汽蒸馏法提取芹菜籽,以1.18%产率获得精油,共检测出23个成分,鉴定出占总精油91.375%的18种成分,主要成分为柠檬烯(31.149%),β-蛇床烯(22.281%),对甲苯基异戊酸酯(14.944%),α-2-丙烯基苯甲醇(9.872%),β-月桂烯(4.324%)和α-蛇床烯(4.322%).  相似文献   
444.
(1) Background: In recent years, the consumption of sprouts, thanks to their high nutritional value, and the presence of bioactive compounds with antioxidant, antiviral and antibacterial properties, is becoming an increasingly widespread habit. Moringa oleifera Lam. (Moringa) seems to be an inexhaustible resource considering that many parts may be used as food or in traditional medicine; on the other hand, Moringa sprouts still lack a proper characterization needing further insights to envisage novel uses and applications. (2) Methods: In this study, a rapid and easy protocol to induce the in vivo and in vitro germination of Moringa seeds has been set up to obtain sprouts and cotyledons to be evaluated for their chemical composition. Moreover, the effects of sprouts developmental stage, type of sowing substrate, and gibberellic acid use on the chemical characteristics of extracts have been evaluated. (3) Results: Moringa seeds have a high germinability, both in in vivo and in vitro conditions. In addition, the extracts obtained have different total phenolic content and antioxidant activity. (4) Conclusions: This research provides a first-line evidence to evaluate Moringa sprouts as future novel functional food or as a valuable source of bioactive compounds.  相似文献   
445.
Root rot is one of the most significant soil and seed-borne fungal diseases, limiting the cultivation of fenugreek plants. Endophytic bacteria and their natural bioproducts have emerged as growth promoters and disease suppressors in the current era. Despite limited research, seeds are a good funder of endophytic microbiomes, which are transmitted from them to other seedling parts, thereby providing a shield against biotic and abiotic anxiety and promoting the growth at early germination and later stages. The current study evaluated the hypothesis that seed endophytic bacteria and their lytic enzymes, growth promotors, and antifungal molecules can induce growth, and inhibit root rot disease development at the same time. The isolation trial from fenugreek seeds revealed a lytic Achromobacter sp., which produces indole acetic acid, has antifungal compounds (e.g., 2-Butanol, 3,3’-oxybis-), and reduces the growth of Rhizoctonia solani by 43.75%. Under the greenhouse and natural field conditions, bacterial cells and/or supernatant improved the growth, physiology, and yield performance of fenugreek plants, and effectively suppressed the progress of root rot disease; this is the first extensive study that uses a new seed-borne endophytic bacterium as a plant-growth-promoting, and biocontrol tool against the sclerotia-forming; R. solani; the causative of fenugreek root rot.  相似文献   
446.
The potentiality of nanomedicine in the cancer treatment being widely recognized in the recent years. In the present investigation, the synergistic effects of chitosan-modified selenium nanoparticles loaded with paclitaxel (PTX-chit-SeNPs) were studied. These selenium nanoparticles were tested for drug release analysis at a pH of 7.4 and 5.5, and further characterized using FTIR, DLS, zeta potential, and TEM to confirm their morphology, and the encapsulation of the drug was carried out using UPLC analysis. Quantitative evaluation of anti-cancer properties was performed via MTT analysis, apoptosis, gene expression analysis, cell cycle arrest, and over-production of ROS. The unique combination of phytochemicals from the seed extract, chitosan, paclitaxel, and selenium nanoparticles can be effectively utilized to combat cancerous cells. The production of the nanosystem has been demonstrated to be cost-effective and have unique characteristics, and can be utilized for improving future diagnostic approaches.  相似文献   
447.
Zinc oxide nanorods were grown on an aluminum-doped zinc oxide seeds layer using the chemical bath deposition method. The effects of growth reaction time on the structural, optical, and photocatalytic properties of zinc oxide nanorods were investigated. It was clearly observed that the growth direction of zinc oxide nanorods were dependent on the crystallinity of the as-deposited aluminum-doped zinc oxide seed layer. The crystallinity of the obtained zinc oxide nanorods was improved with the increase in reaction times during the chemical bath deposition process. The mechanism of zinc oxide nanorod growth revealed that the growth rate of nanorods was influenced by the reaction times. With increasing reaction times, there were much more formed zinc oxide crystalline stacked growth along the c-axis orientation resulting in an increase in the length of nanorods. The longest nanorods and the high crystallinity were obtained from the zinc oxide nanorods grown within 5 h. The optical transmittance of all zinc oxide nanorods was greater than 70% in the visible region. Zinc oxide nanorods grown for 5 h showed the highest degradation efficiency of methyl red under ultraviolet light and had a high first-order degradation rate of 0.0051 min−1. The photocatalytic mechanism was revealed as well.  相似文献   
448.
This work gives a comprehensive chromatographic assessment of biodiesel generation from plant seed oil using ecologically friendly nano-catalysts. Researchers all over the world are actively looking for new ways to satisfy the urgent need for clean and renewable energy sources. The resultant biodiesel was fully characterized utilizing modern techniques like scanning electron microscopy, energy diffraction X-ray and X-ray diffraction. The biodiesel gas chromatography/mass spectrometry analysis revealed four significant peaks of fatty acid methyl esters, indicating high-quality biodiesel production. Furthermore, the biodiesel fuel qualities were discovered to be comparable with international standards such as ASTM D-6571 and EN-14214. This indicates that the iron-modified clay nano-catalyst can be used as a catalyst for large-scale biodiesel production. This work is important because it could lead to the large-scale production of a novel, non-food feedstock. We may lessen our reliance on fossil fuels and contribute to a more sustainable and ecologically friendly energy future by leveraging the usage of biodiesel produced in this way. The chromatographic assessment of biodiesel production from non-edible seed oil using environmentally benign nano-catalysts holds significant promise in advancing sustainable and eco-friendly biodiesel production methods, contributing to a cleaner and more environmentally responsible energy sector.  相似文献   
449.
乌拉尔甘草单粒种子硬实特性的近红外光谱分析   总被引:3,自引:0,他引:3  
以乌拉尔甘草种子为材料,采用近红外光谱结合定性偏最小二乘法对244粒种子(硬实种子和非硬实种子比例为1∶1)的硬实性进行了鉴别研究,并特制一样品杯用于单粒种子的光谱采集,以降低人为误差。研究结果表明,4次重复平均光谱所建模型鉴别率显著高于单次光谱所建模型,光谱范围采用4 000~8 000 cm-1时模型效果较好,校正集、检验集、预测集样本的鉴别率分别为95.53%,95.94%和94.53%,采用不同建模样品所建模型其预测准确率均在90%以上,硬实种子和非硬实种子的预测准确率分别为92.50%和96.56%。种子大小和颜色均会影响模型的鉴别率,种子颜色的影响相对更大。  相似文献   
450.
顾桂定  朱文跃 《计算数学》2004,26(2):211-224
We consider using seed projection methods for solving unsymmetric shifted systems with multiple right-hand sides (A - σjI)x^(j) = b^(j) for 1 ≤ j ≤ p. The methods use a single Krylov subspace corresponding to a seed system as a generator of approximations to the nonseed systems. The residual evaluates of the methods are given. Finally, numerical results are reported to illustrate the effectiveness of the methods.  相似文献   
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