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91.
Krzysztof Buksa Anna NowotnaRafa? Ziobro Halina Gambu?Stanis?aw Kowalski 《Food Hydrocolloids》2012,27(1):72-79
The main constituents of rye flour extracts are proteins and pentosans. After cross-linking under the action of oxidizing agents those components are able to bind much more water than in their native (prior to modifications) state. As a consequence rheological properties of extract are changed.It was observed that kinematic viscosity of water extract of rye flour decreases rapidly with time. The reason for this behavior could be high enzymatic activity of flour extract.It was also found that the addition of hydrogen peroxide in the absence of additional peroxidase (which is naturally present in 1:9 or 1:1 water extracts of flour) causes the greatest increase in viscosity, due to the cross-linking of soluble polymers. Moreover after the addition of H2O2 to water extracts strong gels were obtained, which were characterized by tan δ = 0.5 (tan δ < 1). Moreover G′ was independent of frequency, which also suggests cross-linking of the pentosans.The addition of ascorbic acid, which is known to act preferably on gluten proteins, to 1:9 or 1:1 flour extracts had only a little effect on viscosity. In this case the values of tan δ = 0.9 were close to 1, which is typical for a weak gel.The application of inactivated rye flour extract, containing mainly proteins and pentosans, proved stronger effect of H2O2 in comparison to ascorbic acid on polymer cross-linking, but only after the addition of peroxidase. The gel obtained with H2O2 and peroxidase was also characterized by low tan δ = 0.4.The results indicate, that pentosans are the main subject of cross-linking reactions in rye flour water extracts. 相似文献
92.
93.
Reza Farhoosh Seyedeh-Zohreh Hoseini-Yazdi 《Journal of the American Oil Chemists' Society》2014,91(2):281-293
A comparative study was carried out in order to evaluate the kinetics of the formation of a number of primary and secondary oxidation products during oxidation of olive oil in the Rancimat test at 100–130 °C. There were good correlations between the Rancimat index (OSI) and stability indices (IP) measured in the Rancimat test with no significant differences in kinetic parameters calculated from them. Mean values of the temperature coefficient, Q10 number, activation energy (Ea), frequency factor (A), and free energy of activation (ΔG++) for olive oil oxidation were calculated to be ?3.44 × 10?2°C?1, 2.21, 98.91 kJ/mol, 12.17 × 1012 h?1, and 128.25 kJ/mol, respectively. Each unit change in Ea was accompanied by an average 1.43 × 1012 change in A, indicating a higher contribution for factor A than for Ea to the olive oil stability. The Ea and A correlated well with the values of enthalpy and entropy, respectively. The values of OSI or IP could be described well by the ΔG++ values. Kinetic data indicated that olive oil stability is more affected by the indigenous antioxidants than by the fatty acid composition. 相似文献
94.
《Measurement》2016
The aim of this work is to propose a metrological system for the definition of the Extra Virgin Olive Oil Quality based on Panel Test. The information was obtained by a Kohonen neural network that simulates the biological perception mechanisms. This approach allowed to get a two-dimensional mapping of the flavors based on non-linear model. The predominant flavors are not evenly distribute on the map but they are located in specific zone. It is also possible to identify a separation between negative and positive attributes that defines a “quality direction” from low grade to high quality Extra Virgin Olive Oils. Moreover, the overlaps of different flavors on the same neuron of the map suggest possible correlations between them. This is an important starting point to identify the minimum number of independent attributes in order to optimize the Panel Test questionnaire. 相似文献
95.
S. Weyl-Feinstein A. Markovics H. Eitam A. Orlov M. Yishay R. Agmon J. Miron I. Izhaki A. Shabtay 《Journal of dairy science》2014
Cryptosporidium parvum is considered one of the most common enteropathogens, responsible for the high incidence of diarrhea and deleterious implications on immunity and health in neonatal calves. The pomegranate is well known for its health-promoting properties. Two experiments were designed to test the antiparasitical and antidiarrheal effects of concentrated pomegranate extract (CPE) supplement in milk in neonatal Holstein calves. Forty-one calves were randomly divided into control (n = 20) and treatment (n = 21) groups. For the first experiment, the treatment group was supplemented with 3.75% CPE in the daily milk ration, between 3 and 14 d of age, whereas the control group received only milk. Fecal samples were collected between d 5 and 13 to quantify Cryptosporidium oocysts, and the duration and intensity of diarrhea were evaluated. Reduced fecal oocyst count and diarrhea intensity and duration were revealed in the 3.75% CPE calves. No difference was noted in average daily gain between groups. In a second experiment, which was designed to test the effect of a lower CPE concentration (0.6% of daily milk allocation), no effects on fecal oocyst count and average daily gain were observed. However, compared with control, the lower CPE group was characterized by a shorter duration of diarrhea and higher weight gain among males at 14 d of age. These results suggest that the CPE supplement-to-calf milk ratio may potentially alleviate intestinal morbidity caused by Cryptosporidium. 相似文献
96.
Akila Swaminathan Sree Rama Chaitanya Sridhara Swaraj Sinha Shunmugam Nagarajan Uma Maheswari Balaguru Jamila H Siamwala Saranya Rajendran Uttara Saran Suvro Chatterjee 《Journal of food science》2012,77(12):H273-H279
Abstract: Recent evidence has demonstrated that nitrites play an important role in the cardiovascular system. Fennel (Foneiculum vulgare) seeds are often used as mouth fresheners after a meal in both the Indian sub‐continent and around the world. The present study aims to quantify the nitrite and nitrates in fennel seeds as well as elucidating the effect of fennel derived‐nitrites on vascular functions. Results from our study show that fennel seeds contain significantly higher amount of nitrites when compared to other commonly used post‐meal seeds. Furthermore our study confirmed the functional effects of fennel derived‐nitrites using in vitro and ex vivo models that describe the promotion of angiogenesis, cell migration, and vasorelaxation. We also showed that chewing fennel seeds enhanced nitrite content of saliva. Thus our study indicates the potential role of fennel derived‐nitrites on the vascular system. Practical Application: This study is focused on determining the effect of fennel‐derived nitrites on angiogenesis (the formation of new blood vessels from pre‐existing ones), cell migration, and vasorelaxation (dilation of blood vessels) thereby preserving cardiovascular health. 相似文献
97.
98.
Javad Tavakoli Mary Susan Brewer Aniseh Zarei Jelyani Parviz Estakhr 《International Journal of Food Properties》2017,20(12):3256-3265
The oxidative stability of refined olive oil with incorporated Pistacia khinjuk fruit oil (PKFO; 0.5%, 1%, 2%, 5%, and 10%) during thermal processing at 170ºC for 8 h was evaluated. The conjugated diene values, carbonyl values, acid values, oil/oxidative stability indices, and total tocopherol content were measured during thermal processing. Olive oil containing 0.5% PKFO was identified as the most oxidative stable oil followed by oils containing 100 ppm TBHQ and 1, 5, 10, and 2% PKFO. No significant difference between samples of olive oil containing 100 ppm TBHQ and 1% PKFO was observed. Thus, it was concluded that PKFO at levels lower than 1% could provide stronger antioxidation activity in comparison with TBHQ (the strongest syntactic antioxidant used in the food industry). Moreover, reduction in tocopherol compounds during thermal processing was higher in olive oil containing TBHQ as compared to those in pure olive oil. 相似文献
99.
100.
Abdelkarim Mahdhi Abir Bahi Dorra Mzah Amina Bakhrouf 《Journal of the science of food and agriculture》2013,93(15):3850-3855