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Extraction and microencapsulation of bioactive compounds from pomegranate (Punica granatum var. Wonderful) residues 下载免费PDF全文
Andrés Bustamante Andrea Hinojosa Paz Robert Víctor Escalona 《International Journal of Food Science & Technology》2017,52(6):1452-1462
Pomegranate peels and seeds are industrial residues considered interesting sources of punicalagin (PU) and punicic acid (PA), respectively. To optimise their extraction process and protect them against environmental factors, pomegranate residues were extracted with supercritical CO2 (SC‐CO2) using a Box–Behnken design and then optimal extracts encapsulated by spray‐drying applying a 22 central composite design. Peel extracts showed a PU content of 0.4–9.5% with optimal extraction conditions of 400 bar, 43 °C and 20% ethanol. On the other hand, SC‐CO2 seed extracts showed a PA content of 65.1–78.4% with 450 bar, 48 °C and 10% ethanol as optimal extraction parameters. Otherwise, the encapsulation efficiency of SC‐CO2 extracts was significantly affected by core/wall material ratio and its quadratic effect. This parameter ranged from 35.1% to 72.4% for peel extracts and from 68.2% to 92.7% for seed extracts. Results showed that the proposed technologies are a feasible approach to the integral utilisation of residues from the pomegranate industry. 相似文献
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Şeyda Karaman Esma Tütem Kevser Sözgen Başkan Reşat Apak 《Journal of the science of food and agriculture》2013,93(4):867-875
BACKGROUND: Apples contain a large concentration of phenolic compounds, dependent on factors such as cultivar, harvest, storage conditions, and processing. This study aims to identify the essential phenolic compounds present in various apple varieties, to measure their total antioxidant capacity (TAC) with the CUPRAC (cupric ion reducing antioxidant capacity) and ABTS (2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonate)) methods, and to correlate their TAC values with HPLC findings. RESULTS: The order of TAC (mmol Trolox g?1 fresh weight) of apple peels determined with the CUPRAC method was: Granny Smith > Amasya > Sky Spur > Ervin Spur > King Luscious ≥ Arap Kizi ≥ Lutz Golden. The theoretically calculated TAC values of HPLC‐quantified compounds, with the aid of the combined HPLC‐CUPRAC method, accounted for 18.4–33.5% of the experimentally observed CUPRAC capacity of peel extracts and 19.5–56.3% of flesh extracts, depending on apple variety. CONCLUSION: In synthetic samples of apple antioxidants, the CUPRAC‐TAC values of constituents, identified and analyzed by HPLC, proved to be additive, enabling measurement of the cooperative action of antioxidants using the proposed methodology. Apple peel showed higher contents of phenolics and therefore higher TAC than apple flesh, confirming the health benefit of the consumption of apples together with peel. © 2012 Society of Chemical Industry 相似文献
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Valentina Usenik Franci Stampar Damijana Kastelec 《Journal of the science of food and agriculture》2013,93(3):681-692
BACKGROUND: Plums are a rich source of nutritive and bioactive compounds. The objective was to evaluate the impact of fruit tissue (flesh and peel), ripening stage and cultivar on the composition of phytochemicals in plums (Prunus domestica L.) and to analyse the relation between total antioxidant activity (TAA) and the measured variables. RESULTS: The content of total sugars and total organic acids was higher in flesh but total phenolic content (TPC) and TAA was statistically higher in plum peel. The composition of sugars depended on fruit tissue, ripening stage and the cultivar. Ripening and fruit tissue affected the composition and concentrations of organic acids. TPC of ‘Haganta’ peel increased during ripening but there was no significant time trend for ‘Jojo’ peel and flesh of both cultivars. The composition of phenolics in peel depended on the cultivar, but in flesh on the cultivar and ripening. Ripening resulted in increased total anthocyanins and TAA in peel. TAApeel was positively correlated with TPCpeel, total anthocyaninspeel, cyanidin 3‐glucosidepeel and peonidin 3‐rutinosidepeel in the cultivar ‘Haganta’. CONCLUSION: The composition of phytochemicals in P. domestica fruit depends on fruit tissue, ripening stage and the cultivar. Peel contributes to the TAA on average 20 times more than flesh. © 2012 Society of Chemical Industry 相似文献
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Paul-Aymé Toulemonde Julie Diani Pierre Gilormini Nancy Desgardin Robert Nevière 《The Journal of Adhesion》2018,94(8):657-666
The integrity of propellant/liner structures in rocket motors is critical to ensure controlled combustion of the engine. In an effort to improve the bonding between the liner and the propellant, it is necessary to characterize it well. Therefore, a propellant–liner structure, bounded thanks to co-curing, has been submitted to a peel test while recording the macroscopic fracture energy and the local displacement field on the propellant-free surface. The experimental setup includes two cameras in order to record the displacement field on the propellant-free surface. Upon loading, the peel force stabilizes quickly due to a cohesive fracture in the propellant, providing access to the fracture energy. While the crack propagates through the propellant, it is observed that only a small localized area is submitted to strain, and most of the structure remains unstrained. 相似文献
58.
本文介绍了一种新的覆铜板箔胶粘剂,应用于酚醛纸板上,具有较高的耐漏电起痕性;研究了胶粘剂的合成、铜箔涂胶及层压板制造等工艺。 相似文献
59.
动力学在香蕉涂膜保鲜中应用的研究 总被引:1,自引:0,他引:1
陈复生 《河南工业大学学报(自然科学版)》1995,(1)
本文研究了香蕉涂膜前后呼吸反应的动力学过程;建立了香蕉呼吸强度R_(co_2)、气体渗透系数P_g与温度T、二氧化碳浓度Y、时间τ、薄膜厚度δ之间的动力学方程式;根据实验测试数据确定了方程式中的常数K_1、K_2、K_(co_2),、E和b。分析了可食用CASP保鲜薄膜的特性和对香蕉的保鲜效果。从而选择和控制了香蕉的最佳保鲜条件。 相似文献
60.
Optimization of Blanching for Crispness of Banana Chips Using Response Surface Methodology 总被引:1,自引:0,他引:1
Whole green bananas were blanched in water at 50, 60, 70, 80, 90, and 100°C for 2, 15, and 30 min using a factorial design then peeled, sliced and fried in oil to make chips. Crispness was measured using a bending-snapping test in the TA.XT2 Texture Analyzer. Significant interactions were found between blanch time and temperature and crispness of chips. A second experiment was then performed using a central composite design and blanch temperatures from 41.7 to 98.3°C. Response surface analysis predicted that crispiest chips should be produced at blanching conditions of 69°C and 22 min. 相似文献