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91.
Sung Nak-Yun Choi Jong-il Yoon Yohan Lee Soo-Young Byun Myung-Woo Hwang Yeoung-Jung Koenari Zubaidah Irawati Lee Ju-Woon Kim Jae-Hun 《Food science and biotechnology》2011,20(3):841-844
This study evaluated the anti-allergic effect of low molecular weight β-glucan (25 kDa) degraded by λ-irradiation. Allergy
was induced in mouse models administrated with λ-irradiated low molecular weight and non-irradiated high molecular weight
β-glucan, respectively, for 7 days. However, only the mice treated with low molecular weight β-glucan had a significantly
decreased the total serum IgE and ovalbumin specific-IgE levels, and significantly increased Th 1 cytokine expression compared
to only allergy induced mice. The allergic responses could be reduced by low molecular weight β-glucan treated λ-irradiation
through the increased expression of Th 1 response and decreased expression of total IgE and antigen specific IgE. 相似文献
92.
Seok-Chun Ko Min Cheol Kang Jung-Kwon Lee Hee-Guk Byun Se-Kwon Kim Seung-Cheol Lee Byong-Tae Jeon Pyo-Jam Park Won-Kyo Jung You-Jin Jeon 《European Food Research and Technology》2011,233(6):915-922
Angiotensin I-converting enzyme (ACE) inhibitory peptide was isolated from Styela plicata. The S. plicata was hydrolyzed with various proteases including Protamex, Kojizyme, Neutrase, Flavourzyme, Alcalase, trypsin, α-chymotrypsin,
pepsin, and papain. The hydrolysate prepared with Protamex had the highest ACE inhibitory activity compared to the other hydrolysates.
We attempted to isolate ACE inhibitory peptides from hydrolysate prepared with Protamex using ultra-filtration, gel filtration
on a Sephadex G-25 column and reversed-phase high-performance liquid chromatography (RP-HPLC) on an ODS column. IC50 value of the purified ACE inhibitory peptide was 24.7 μM, and Lineweaver–Burk plots suggest that the purified peptide from
S. plicata acts as mixed-type inhibitor against ACE. Amino acid sequence of the purified peptide was identified as Met-Leu-Leu-Cys-Ser,
with a molecular weight 566.4 Da. The results of this study suggest that peptides derived from S. plicata may be beneficial as anti-hypertension compounds in functional foods resource. 相似文献
93.
Bioactive properties of enzymatic hydrolysates from abdominal skin gelatin of yellowfin tuna (Thunnus albacares)
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Yuna Han Sang‐Hun Byun Joung‐Hyun Park Seon‐Bong Kim 《International Journal of Food Science & Technology》2015,50(9):1996-2003
Gelatin (90.6 ± 0.1%) was optimally prepared by response surface methodology from yellowfin tuna (Thunnus albacares, YT) abdominal skin. To investigate bioactive properties of enzymatic hydrolysates from the abdominal skin gelatin (ASG), ASG was hydrolysed with alcalase, protamex, neutrase and flavourzyme as affected by hydrolysis time. Antioxidant, nitrite scavenging and angiotensin‐I converting enzyme (ACE) inhibitory activities of the hydrolysates were determined. Antioxidant activities of the hydrolysates were found through linoleic acid peroxidation inhibitory effects. Alcalase‐derived hydrolysates (AHs) were more effective than others in metal ions chelating, superoxide anion scavenging and hydroxyl radical scavenging activities (P < 0.05). AHs showed significantly stronger nitrite scavenging activities (44.4–60.7%) than others (P < 0.05). Fraction A from AH showed strong ACE inhibitory activity (IC50 of 0.75 mg mL?1). These results suggest that YT ASG and its enzymatic hydrolysates could be functional food and/or pharmaceutical ingredients with potent antioxidant, anticarcinogenic and antihypertensive benefits. 相似文献
94.
Kye-Hwan Byun Shin Young Park Dong Un Lee Hyang Sook Chun 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2020,37(3):507-518
ABSTRACTThis study investigated the antifungal effect of ultraviolet-C (UV-C) against Aspergillus flavus and Aspergillus parasiticus on roasted coffee beans. Also, any changes in the quality of the roasted coffee beans were measured after UV-C irradiation. As UV-C irradiation time increased (0–2 h), the number of surviving A. flavus and A. parasiticus spores significantly (P < .05) decreased. The reduction values of A. flavus in round part, crack part, and whole roasted coffee beans were 2.16, 0.71, and 1.58 log10 CFU g?1, respectively, and the reduction values of A. parasiticus in round part, crack part, and whole roasted coffee beans were 1.03, 0.37, and 0.72 log10 CFU g?1, respectively, after 2 h of UV-C irradiation. Field emission scanning electron microscopy showed that the morphology of A. flavus and A. parasiticus spores included expanded wrinkles that were deformed by UV-C irradiation. The Hunter colours were significantly reduced (P < .05). There was no significant change (P > .05) in moisture content, but the pH was significantly decreased (P < .05). Most of the sensory parameters did not change, but there was a significant difference (P < .05) in flavour. Based on this study, 2 h of UV-C irradiation was effective in reducing 90% of A. flavus, but it was not effective against A. parasiticus present on roasted coffee beans. Also, Hunter colour, pH, and sensory parameters (flavour) were changed by UV-C irradiation. 相似文献
95.
A resilient buffer allocation scheme in active queue management: a stochastic cooperative game theoretic approach
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During the last decade, a plentiful number of active queue management schemes have been proposed, but their main objectives are simply allocating the buffer resource to all flows evenly, or protecting responsive flows from being degraded by unresponsive flows. However, the sending rates of the responsive flows can be determined diversely, and not all unresponsive flows have aggressively high sending rates. Furthermore, it is rational to reserve a portion of the buffer resource for certain privileged traffic. Grounded by these evidences, in this paper, we present a resilient active queue management algorithm, named Prior‐Core‐based Buffer Allocation considering diverse congestion control algorithms, fair‐unresponsive flows, and some privileged traffic. Our approach is based on stochastic cooperative game theory, where the payoffs yielded by cooperation are described by random variables, and the core is defined only over the distribution of these random payoffs; the core in this situation is called the prior‐core. As a result, it is shown that our buffer allocation, yielded by the prior‐core, achieves completely fair allocation for those flows whose requirement does not exceed the fair‐share regardless of the responsiveness, whereas aggressive flows are restricted according to availability of the buffer; all these are verified through ns‐2 simulation experiments. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
96.
97.
In this paper, a method of accurate position control using a pneumatic cylinder driving apparatus is presented. To overcome
the effect of friction force and transmission line, low friction type cylinder applied externally pressurized air bearing
structure is used and two control valves attached both side of the cylinder directly. To compensate nonlinear characteristics
of control valves, linearized control input derived from the relation between control input and effective area of control
valve, and dither signal are applied to the valve. The controller applied to the pneumatic cylinder driving apparatus is composed
of a state feedback controller and a disturbance observer. Experimental results show that the effectiveness of the proposed
method and position control error of 5 μm accuracy could be obtained easily. 相似文献
98.
Currently, studies on autonomous driving are being actively conducted. Vehicle positioning techniques are very important in the autonomous driving area. Currently, the global positioning system (GPS) is the most widely used technology for vehicle positioning. Although technologies such as the inertial navigation system and vision are used in combination with GPS to enhance precision, there is a limitation in measuring the lane and position in shaded areas of GPS, like tunnels. To solve such problems, this paper presents the use of LED lighting for position estimation in GPS shadow areas. This paper presents simulations in the environment of three‐lane tunnels with LEDs of different color temperatures, and the results show that position estimation is possible by the analyzing chromaticity of LED lights. To improve the precision of positioning, a fuzzy logic system is added to the location function in the literature [1]. The experimental results showed that the average error was 0.0619 cm, and verify that the performance of developed position estimation system is viable compared with previous works. 相似文献
99.
100.
Gun-Hee Lee Jin-Kwan Park Junyoung Byun Jun Chang Yang Se Young Kwon Chobi Kim Chorom Jang Joo Yong Sim Jong-Gwan Yook Steve Park 《Advanced materials (Deerfield Beach, Fla.)》2020,32(8):1906269
Inspired by the human somatosensory system, pressure applied to multiple pressure sensors is received in parallel and combined into a representative signal pattern, which is subsequently processed using machine learning. The pressure signals are combined using a wireless system, where each sensor is assigned a specific resonant frequency on the reflection coefficient (S11) spectrum, and the applied pressure changes the magnitude of the S11 pole with minimal frequency shift. This allows the differentiation and identification of the pressure applied to each sensor. The pressure sensor consists of polypyrrole-coated microstructured poly(dimethylsiloxane) placed on top of electrodes, operating as a capacitive sensor. The high dielectric constant of polypyrrole enables relatively high pressure-sensing performance. The coils are vertically stacked to enable the reader to receive the signals from all of the sensors simultaneously at a single location, analogous to the junction between neighboring primary neurons to a secondary neuron. Here, the stacking order is important to minimize the interference between the coils. Furthermore, convolutional neural network (CNN)-based machine learning is utilized to predict the applied pressure of each sensor from unforeseen S11 spectra. With increasing training, the prediction accuracy improves (with mean squared error of 0.12), analogous to humans' cognitive learning ability. 相似文献