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971.
Thermal QCD     
By the methbd of the gauge field theory at finite temperature, the static thermodynamic properties in quark-gluon plasma are studied in detail. According to the renormalization group equation, an analytic expression of the running coupling constant g(T, p) with the temperature T is obtained.  相似文献   
972.
通过图像扫描仪获得的彩色图像常包含有一些样稿颜色以外的杂色或噪声颜色,当用基于一维直方图的传统的颜色统计法进行颜色分割时,会出现错分现象。对此,本文提出了基于二维直方图的颜色分割新方法,实现了一些CAD系统图像颜色的准确分割和归并。实验结果和实际应用都证明了新方法的有效性,该方法也可应用于全真彩色图像的量化。  相似文献   
973.
为改善彩色等离子体显示器(PDP)的白平衡,研究了维持期寻址电极辅助脉冲对PDP亮度的影响,提出了辅助脉冲数调制改善PDP白平衡的新方法。通过在各子场对三基色寻址电极分别加幅度、宽度和延时相同,但数目不同的辅助脉冲,从而改变三基色之间的亮度比率,使每个子场和各灰度级的白平衡满足要求,改善了全屏白平衡一致性,而不需要改变现有电路硬件设计,不增加额外电源。实验结果表明,在整个灰度区间,PDP的白平衡平均从0.021改善到0.0025,并且分布在较小的色温区间。  相似文献   
974.
Cold-hardy interspecific hybrid grape varieties (Vitis spp.) have distinctive chemical compositions such as high acidity, a high content of anthocyanin diglucoside and a low condensed tannins content, compared to Vitis vinifera varieties. Considering the importance of phenolic compounds on the quality of red wine, a mechanical maceration technique, accentuated cut edges (ACE), has been evaluated when applied directly to crushed grapes (ACE-C), and 24 h before pressing (ACE-P), to improve the extraction of phenolic compounds. Samples were collected at crushing, bottling, and after five months of aging. Phenolic compounds and color characteristics of the wines were analyzed by high-performance liquid chromatography (HPLC) with diode array and fluorescence detectors and UV-Visible spectrophotometry. The color intensity, non-anthocyanin monomeric compounds and total iron-reactive phenolics content increased after applying ACE, compared to the control (CTL) after aging, and was significantly higher (37%) after ACE-C, compared to ACE-P. However, the concentration of condensed tannins was below the limit of detection in all the samples, indicating that ACE did not help their extraction or further interactions occurred with disrupted cell wall material. Applying ACE at crushing was considered as the optimum time to achieve a higher color stability in Marquette red wines.  相似文献   
975.
Karhunen-Loeve及多尺度金字塔联合变换的彩色逆半调算法   总被引:1,自引:0,他引:1  
孔月萍  曾平  吴自力 《光学学报》2007,27(10):1745-1750
红绿蓝(RGB)颜色空间中的各颜色分量具有高度相关性,直接分通道实施的彩色逆半调方法会残留大量人眼敏感的半调纹理,且逆半调图像色偏较大。从分析矢量误差分散半调系统模型入手,推导其加噪特性,针对性地提出了一种Karhunen-Loeve(K-L)及多尺度金字塔联合变换的彩色逆半调算法。算法以K-L变换减弱彩色分量相关性,再利用多尺度中值金字塔算子以及维纳(Wiener)滤波分离并抑制高频细节子图中的半调噪声,最后进行中值金字塔、K-L逆变换重构结果图像。实验表明,该算法能有效去除半调噪声、减小重建图像的颜色偏差,与直接分通道逆半调算法相比峰值信噪比值提高约2~3 dB,且重建图像视觉效果良好。  相似文献   
976.
The drying process preserves the surplus of perishable food. However, to obtain a good-quality final product, different pretreatments are conducted before drying. Thus, the aim of the study was the evaluation of the effect of thermal (blanching treatments with hot water) and non-thermal technologies (pulsed electric field (PEF) and ultrasound (US)) on the kinetics of the drying process of red bell pepper. The convective and microwave–convective drying were compared based on quality parameters, such as physical (water activity, porosity, rehydration rate, and color) and chemical properties (total phenolic content, total carotenoids content, antioxidant activity, and total sugars content). The results showed that all of the investigated methods reduced drying time. However, the most effective was blanching, followed by PEF and US treatment, regardless of the drying technique. Non-thermal methods allowed for better preservation of bioactive compounds, such as vitamin C in the range of 8.2% to 22.5% or total carotenoid content in the range of 0.4% to 48%, in comparison to untreated dried material. Moreover, PEF-treated red bell peppers exhibited superior antioxidant activity (higher of about 15.2–30.8%) when compared to untreated dried samples, whereas sonication decreased the free radical scavenging potential by ca. 10%. In most cases, the pretreatment influenced the physical properties, such as porosity, color, or rehydration properties. Samples subjected to PEF and US treatment and dried by using a microwave-assisted method exhibited a significantly higher porosity of 2–4 folds in comparison to untreated material; this result was also confirmed by visual inspection of microtomography scans. Among tested methods, blanched samples had the most similar optical properties to untreated materials; however non-thermally treated bell peppers exhibited the highest saturation of the color.  相似文献   
977.
Basil-based semi-finished products, which are mainly used as an intermediate to produce the typical pesto sauce, are prepared and exported all over the world. Color is a fundamental organoleptic requirement for the acceptability of these semi-finished products by the manufacturers of the pesto sauce. Some alternative formulations, which adjust the typical industrial recipe by both changing the preservative agent (ascorbic acid, citric acid, or a mixture of both) and introducing a preliminary thermic treatment (blast chilling), were evaluated. In this work, a fast and non-destructive spectrophotometric analysis, to monitor the color variations in these food products during their shelf-life, was proposed. The raw diffuse reflectance spectra (380–900 nm) obtained by a UV–visible spectrophotometer, endowed with an integrating sphere, together with the CIELab parameters (L*, a*, b*) automatically obtained from these, were considered, and elaborated using multivariate statistical analysis (principal component analysis). From this preliminary study, blast chilling, together with the use of ascorbic acid, proved to be the best solution to better preserve the color of these products during their shelf-life.  相似文献   
978.
The color of rosé wines is extremely diverse and a key element in their marketing. It is due to the presence of anthocyanins and of additional pigments derived from them and from other wine constituents. To explore the pigment composition and determine its links with color, 268 commercial rosé wines were analysed. The concentration of 125 polyphenolic compounds was determined by a targeted metabolomics approach using ultra high-performance liquid chromatography coupled to triple quadrupole mass spectrometry (UHPLC-QqQ-MS) analysis in the Multiple Reaction Monitoring (MRM) mode and the color characterised by spectrophotometry and CieLab parameters. Chemometrics analysis of the composition and color data showed that although color intensity is primarily determined by polyphenol extraction (especially anthocyanins and flavanols) from the grapes, different color styles correspond to different pigment compositions. The salmon shade of light rosé wines is mostly due to pyranoanthocyanin pigments, resulting from reactions of anthocyanins with phenolic acids and pyruvic acid, a yeast metabolite. Redness of intermediate color wines is related to anthocyanins and carboxypoyranoanthocyanins and that of dark rosé wines to products of anthocyanin reactions with flavanols while yellowness of these wines is associated to oxidation.  相似文献   
979.
In the context of the increasing lactation problems among breastfeeding women, the development of a healthy lifestyle is needed. Different variants of pork, turkey, and beef meatballs, with added lemon balm (Melissa officinalis L.) and wild thyme (Thymus serpyllum L.) aqueous extract (6%), were obtained. These herbs were selected and used due to their antioxidant, antimicrobial, and lactogenic potential. Two thermal treatments, hot air convection (180 °C) and steam convection (94 °C), were applied for meatballs processing. The obtained meatballs were further subjected to a complex characterization. The functionality of the plant extracts was proved by the values of total content of polyphenols (2.69 ± 0.02 mg AG/g dw) and flavonoids (3.03 ± 0.24 mg EQ/g dw). FT-IR analysis confirmed the presence of trans-anethole and estragole at 1507–1508 cm−1 and 1635–1638 cm−1, respectively. Costumers’ overall acceptance had a score above 5.5 for all samples, on a scale of 1 to 9. Further analysis and human trials should be considered regarding the use of lactogenic herbs, given their health benefits and availability.  相似文献   
980.
Most LLIE algorithms focus solely on enhancing the brightness of the image and ignore the extraction of image details, leading to losing much of the information that reflects the semantics of the image, losing the edges, textures, and shape features, resulting in image distortion. In this paper, the DELLIE algorithm is proposed, an algorithmic framework with deep learning as the central premise that focuses on the extraction and fusion of image detail features. Unlike existing methods, basic enhancement preprocessing is performed first, and then the detail enhancement components are obtained by using the proposed detail component prediction model. Then, the V-channel is decomposed into a reflectance map and an illumination map by proposed decomposition network, where the enhancement component is used to enhance the reflectance map. Then, the S and H channels are nonlinearly constrained using an improved adaptive loss function, while the attention mechanism is introduced into the algorithm proposed in this paper. Finally, the three channels are fused to obtain the final enhancement effect. The experimental results show that, compared with the current mainstream LLIE algorithm, the DELLIE algorithm proposed in this paper can extract and recover the image detail information well while improving the luminance, and the PSNR, SSIM, and NIQE are optimized by 1.85%, 4.00%, and 2.43% on average on recognized datasets.  相似文献   
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