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101.
Coralia Osorio Nelson Hurtado Corinna Dawid Thomas Hofmann Francisco José Heredia-Mira Alicia Lucía Morales 《Food chemistry》2012
The anthocyanin composition of tamarillo (Solanum betaceum Cav., red variety) and Andes berry (Rubus glaucus Benth.) was determined by HPLC–PDA and HPLC–ESIMS. From the anthocyanin-rich extracts (AREs), pure compounds (1–7) were obtained by MLCCC (multilayer countercurrent chromatography) and further preparative HPLC, and their unequivocal structures were obtained by 1D and 2D NMR analyses. The new anthocyanin delphinidin 3-O-α-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranoside-3′-O-β-d-glucopyranoside, as well as the known cyanidin-3-O-rutinoside, pelargonidin-3-O-rutinoside, and delphinidin-3-O-rutinoside were identified as constituents of tamarillo fruit. Although the anthocyanin composition of Andes berry had been reported before in the literature, the unequivocal structure elucidation of the major compound, cyanidin-3-O-α-l-rhamnopyranosyl-(1 → 6)-O-β-d-xylopyranosyl-(1 → 2)-β-d-glucopyranoside, was achieved for the first time. 相似文献
102.
Kashif Ghafoor Sun‐Ok Kim Dong‐Un Lee Kijun Seong Jiyong Park 《Journal of the science of food and agriculture》2012,92(15):2975-2982
BACKGROUND: The conventional method of processing ginseng (Panax ginseng) roots into red ginseng involves mainly heating and drying processes. In the present study, this method was modified by using high hydrostatic pressure (HHP) to improve the physicochemical characteristics of red ginseng. RESULTS: The HHP process (600 MPa for 1 min) significantly improved the histological properties of red ginseng by increasing cellular disruption and release of cell contents. The total reducing sugar content was significantly (P < 0.05) higher (increased from 10.67 to 15.25 mg g?1) in red ginseng processed at 600 MPa for 1 min. Similarly, the total free amino acid content also increased significantly (from 2.81 to 7.77 mg g?1). The HHP process resulted in superior and more even colouration and gave an attractive visual appearance to red ginseng. The optical density at 420 nm and Hunter's colour a value (redness) of extracts prepared from red ginseng increased significantly (P < 0.05) with the application of HHP. CONCLUSION: HHP‐processed red ginseng has significantly higher reducing sugar and free amino acid contents together with a more compact cell structure and superior visual quality (brighter red colour). Hence the application of HHP in red ginseng processing can result in ginseng products of improved quality compared with those obtained by the conventional method. Copyright © 2012 Society of Chemical Industry 相似文献
103.
Synthesis of flavonols and expression of flavonol synthase genes in the developing grape berries of Shiraz and Chardonnay (Vitis vinifera L.) 总被引:1,自引:0,他引:1
MARK O. DOWNEY JOHN S. HARVEY SIMON P. ROBINSON 《Australian Journal of Grape and Wine Research》2003,9(2):110-121
Flavonols were determined in Shiraz and Chardonnay grapes throughout berry development. The predominant flavonols were quercetin-3-glycosides with trace amounts of kaempferol-3-glycosides detected in Shiraz flowers but not in developing berries. Flavonols were present in the skin of ripening grapes but were not detected in seeds or flesh. Flavonols were also present in buds, tendrils, inflorescences, anthers and leaves. The concentration of flavonols in flowers (mg/g fresh weight) was high and decreased between flowering and berry set then remained relatively constant through berry development. The total amount of flavonols in berries (mg/berry) was low until pre-veraison then increased during berry development, particularly before veraison, the onset of ripening, in Chardonnay and during ripening in Shiraz. Two cDNA fragments with homology to genes encoding the enzyme flavonol synthase (FLS) were isolated from Shiraz flowers. In the overlapping region of the two cDNAs, they had 80% sequence identity at the nucleotide level and both had high homology to FLS genes from other plants. VvFLS1 was expressed in leaves, tendrils, pedicels, buds and inflorescences as well as in developing grapes. Expression was highest between flowering and fruit set then declined, increasing again during ripening coincident with the increase in flavonols per berry. Expression of VvFLS2 was much lower than for VvFLS1 and did not change during berry development. The results indicate that two distinct periods of flavonol synthesis occur in grapes, the first around flowering and the second during ripening of the developing berries. 相似文献
104.
105.
探究人参与大蒜混合发酵对黑参微生物多样性、成分以及生理功能的影响。以新鲜大蒜和人参为原料,采用液态发酵法自制黑蒜、黑参和参蒜,对其发酵过程中微生物多样性、主要成分以及抗氧化性进行分析。结果表明:参蒜产品的优势菌门为厚壁菌门,优势菌属为uncultured_bacterium_f_Muribaculaceae、乳杆菌属等;根据京都基因与基因组百科全书进行代谢途径预测,参蒜与大蒜和人参的代谢途径无明显差异,主要为全局及概要图、碳水化合物代谢和氨基酸代谢;参蒜的还原糖含量和总酚含量显著提高,总酸含量下降,稀有人参皂苷转化率显著提高,潜在有害物质5-羟甲基糠醛含量显著下降;参蒜具有良好的自由基清除能力。以上研究为参蒜产品的开发、促进黑参产业的发展提供理论依据。 相似文献
106.
5种浆果果酒抗氧化活性差异及综合评价 总被引:2,自引:0,他引:2
该研究测定了5种浆果(蓝莓(野生和北陆)、蓝靛果(野生和蓓蕾)、不老莓)果酒的理化指标、单体酚类物质含量和抗氧化活性,探究5种浆果果酒抗氧化活性差异,并通过主成分分析(PCA)对其进行综合评价。结果表明,野生蓝靛果果酒中的总糖、总酸、多酚、黄酮、花色苷含量最高,分别为3.82%、9.69 mg/g、12.58 mg/g、1.55%、1.21 mg/g,单体酚类物质中咖啡酸、儿茶素、表儿茶素、绿原酸、对香豆酸、芦丁含量最高,分别为66.19 mg/g、878.09 mg/g、13.28 mg/g、735.50 mg/g、275.32 mg/g、23.86 mg/g,其DPPH·清除率(92.29%)、 ·OH清除率(96.28%)和还原力(1.744)最强;野生蓝莓果酒的ABTS+·清除率(96.77%)和O2-·的清除率(50.54%)最强;浆果果酒综合得分表明,5种浆果果酒的抗氧化活性排序为野生蓝莓果酒>野生蓝靛果果酒>蓓蕾蓝靛果果酒>不老莓果酒>北陆蓝莓果酒。 相似文献
107.
Evaluation of Protective Effect of Freeze‐Dried Strawberry,Grape, and Blueberry Powder on Acrylamide Toxicity in Mice 下载免费PDF全文
Mengyao Zhao Xin Liu Yinghua Luo Huan Guo Xiaosong Hu Fang Chen 《Journal of food science》2015,80(4):H869-H874
Berries are dietary plants with high antioxidant activity. The aim of this study is to investigate the protective effect of berries (strawberry, grape, and blueberry) against the acrylamide (AA)‐induced general toxicity, genotoxicity, and reproductive toxicity in mice model, respectively. Mice were treated with 50 mg/kg b.w./day AA intraperitoneal injection for 5 d after feeding control diet or diet containing freeze‐dried strawberry, grape, and blueberry powder. The results showed that AA induced a significant general toxicity, genotoxicity, and reproductive toxicity in mice. Compared with the control diet, the diets containing berries could reverse the AA‐induced alterations in liver antioxidant enzymes activities (P < 0.05). Moreover, the AA‐induced genotoxicity could be prevented by the diet containing berries. The DNA damage in the lymphocyte and liver cells and the micronucleus formation in bone marrow cell were significantly alleviated (P < 0.05). Meanwhile, the mice fed with diets containing berries showed a recovery in the sperm count, the sperm activity rate, sperm motility parameters, and the abnormal sperm rate (P < 0.05). Berry powders have remarkable intervention against the AA‐induced general toxicity, genotoxicity, reproductive toxicity. Abundant phenolics, especially anthocyanins, may contribute to the intervention. 相似文献
108.
109.
以酸浆果为试材,研究H2SO4体积浓度、液料比、水解时间、提取温度对酸浆果结合酚得率的影响及结合酚体外抗氧化能力。采用中心组合设计优化结合酚提取工艺,通过·OH、ABTS^+·及FRAP法评价结合酚体外抗氧化能力。结果表明,酸浆果结合酚最佳提取工艺为:H2SO4浓度5%,液料比55︰1 mL/g,水解时间16 h,提取温度45℃。此条件下提取得到的结合酚含量8.83±0.18 mg/g。酸浆果结合酚还原铁能力与BHT相当,比VC强,酸浆果游离酚原铁能力介于BHT与VC间(p<0.01);酸浆果结合酚、游离酚都有一定的ABTS^+·清除能力,都比VC、BHT清除能力弱(p<0.01),对·OH基团表现出一定还原能力,均比VC、BHT清除能力弱(p<0.01)。研究为酸浆果结合酚开发和利用提供依据,避免资源浪费。 相似文献
110.