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Vijay Singh Sharanagat Prabhat K. Nema Lochan Singh Ankur Kumar 《International Journal of Food Science & Technology》2022,57(3):1654-1665
The effect of microwave roasting parameters (300, 450 and 600 W; 5, 10 and 15 min) on acrylamide content in sorghum grain was determined using High Pressure Liquid Chromatography (HPLC)-photo diode array (PDA) detector coupled with C-18 column. Samples roasted at 300 and 450 W did not possess acrylamide, whereas 600 W (15 min) favoured formation of 2740.19 µg/kg of acrylamide, levels far exceeding the defined European Union (EU) limits. The chronic daily intake (CDI) for acrylamide through consumption of such grain flour was 3.25–9.5-fold higher to Joint FAO/WHO Expert Committee on Food Additives (JECFA) defined high exposure limits. The margin of exposure (MOE) values ranged from 4.3 to 12.76 and from 11.07 to 32.27 for neoplastic and neurological effects, respectively, demonstrating high exposure and serious health concerns associated with dietary intake of this toxicant. This study assesses the risk for the Indian population and highlights the importance of optimising process parameters for food product to minimise such exposure risks. 相似文献
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Due to low oil recovery factor in heavy oil reservoir, air injection with catalyst becomes a competitive technology to effectively reduce viscosity of crude oil as a result of the low cost and small environment pollution. This paper determined the feasibility of air injection with catalyst in a heavy oil reservoir through static and dynamic experiments. The results indicated that under the effect of catalyst, oxidation between heavy oil and air could significantly reduce the viscosity of crude oil. The optimal catalyst contained 0.7?wt. % oil-solubility organic acid copper and 0.5?wt. % sodium hydroxide. With the oxidation time increasing, viscosity of crude oil decreased and oil recovery factor increased. With temperature increasing, viscosity of crude oil decreased sharply and oil recovery factor increased. The oil recovery factor of air huff-n-puff process was 30.2%. Air injection with catalyst in the reservoir is a promising technology. 相似文献
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为开发富含膳食纤维的低温鱼肉香肠,以鹰嘴豆粉、草鱼肉为实验材料,设计单因素试验,研究不同添加量鹰嘴豆粉对鱼肉香肠质构、色泽、凝胶强度、持水率及蒸煮损失率等品质特性的影响。结果表明:添加鹰嘴豆粉对鱼肉香肠的质构特性、色泽、凝胶强度及保水性均产生影响,鹰嘴豆粉添加量0%~10%时,鱼肉香肠的硬度、咀嚼性、凝胶强度和持水率出现先上升后下降趋势,其中鹰嘴豆粉添加量6%时达到最大值,而蒸煮损失率、亮度值和白度显著减小(P<0.05),鹰嘴豆粉添加量大于6%时蒸煮损失率下降趋于平缓。综上可知,鹰嘴豆粉可以影响低温鱼肉香肠食用品质,在鹰嘴豆粉添加量为6%时,各项指标均趋于理想范围,因此鹰嘴豆粉的最佳添加量为6%。鱼肉香肠中添加适量鹰嘴豆粉不仅能改善香肠品质,还能赋予鱼肉香肠鹰嘴豆特有风味。 相似文献
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低温氮气吸附实验是研究致密储集层微观结构特征的重要手段之一,目前在碎屑岩致密储集层研究中取得了较好的效果。应用低温氮气吸附实验,研究三塘湖盆地石炭系火山岩致密储集层纳米级孔隙的成因。实验分析表明:三塘湖盆地上石炭统哈尔加乌组火山岩低温氮气吸附等曲线以墨水瓶形为主,随着深度增加,样品的平均孔径逐渐减小,总孔体积逐渐增大,样品比表面积逐渐增大,表征孔隙表面粗糙程度的分形维数也增大。结合场发射扫描电镜分析表明,三塘湖盆地哈尔加乌组火山岩致密储集层的微观孔隙结构形态与溶蚀作用有关,储集层埋藏越深,介于火山岩内部的烃源岩生成的有机酸越多,溶蚀作用就越强烈,长石等不稳定矿物溶蚀以后,形成新的矿物在喉道沉淀,一方面增加储集层的微观孔隙体积,另一方面降低了储集层渗透率。 相似文献
6.
《Journal of the European Ceramic Society》2020,40(15):5369-5375
This work reports on direct crystallization of PbZr0.53Ti0.47O3 (PZT) thin films on glass and polymeric substrates, using pulsed thermal processing (PTP). Specifically, xenon flash lamps deliver pulses of high intensity, short duration, broadband light to the surface of a chemical solution deposited thin film, resulting in the crystallization of the film. Structural analysis by X-ray diffraction (XRD) and transmission electron microscopy show the existence of perovskite structure in nano-sized grains (≤5 nm). Local functional analysis by band excitation piezoelectric spectroscopy and electrostatic force microscopy confirm the presence of a ferroelectric phase and retention of voltage-written polarization for multiple days. Based on structural and functional analyses, strategies are discussed for optimization of pulse voltage and duration for the realization of crystalline ferroelectric thin films. For ∼200 nm-thick PZT films on glass substrates, 500 μs-long pulses were required for crystallization, starting with 100 pulses at 350 V, 10 or 25 pulses at 400 V and in general lower number of pulses at higher voltages (resulting in higher radiant energy). Overall power densities of >6.4 kW/cm2 were needed for appearance of peaks corresponding to the perovskite phase in the XRD. Films on glass processed at 350–400 V had a higher degree of 111-oriented perovskite grains. Higher applied radiant energy (through increased pulse voltage or count) resulted in more random and/or partially 001-oriented films. For ∼1 μm-thick PZT films on polymeric substrates, 10 to 25 250 μs-long pulses at voltages ranging between 200 to 250 V, corresponding to power densities of ∼2.8 kW/cm2, were optimal for maximized perovskite phase crystallization, while avoiding substrate damage. 相似文献
7.
《中国有色金属学会会刊》2020,30(5):1419-1428
Anodic processes on Cu−10Al electrode in molten KF−AlF3−Al2O3 (saturated) and suspensions were characterized using chronopotentiometric and cyclic voltammetric techniques. Effects of cryolite ratio (CR= x(KF)/x(AlF3)), temperature and particle volume fraction (ϕ) on the electrochemical behaviour of the anode were demonstrated. Initially, the anode was polarised in the galvanostatic mode in melt and suspensions (ϕ=0.12, 0.15) at 750 °C with 0.4 A/cm2 current density. The anode potential in melt varied between 2.5 and 3.2 V and in suspensions (ϕ= 0.12) between 3.3 and 3.4 V. XRD analysis was conducted to study the oxide phases on the anode surface. Anode limiting current densities and mass transfer coefficients drastically decreased with the increase of ϕ in the suspension. The results suggest that the Cu−10Al electrode works better in suspensions with CR of 1.4 and particle volume fraction of 0.09 at 800 °C. 相似文献
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The effect of biochar substituted for anthracite as reductant on magnetizing-roasting pyrite cinder was investigated.The key of magnetizing-roasting is the gasification reaction between reductants and CO2.Since biochar could react with CO2 more rapidly at lower temperature,the reactivity of biochar is better than that of anthracite.The gasification of biochar could produce reducing condition ofφCO/(φCO+φCO2)about 10%-20% between 700-800 ℃,which is in accord with the atmosphere and temperature of Fe2O3 reduction.So it is beneficial to the reduction of iron mineral of pyrite cinder.Compared with anthracite,biochar could decrease the roasting temperature from825 to 750 ℃ and roasting time from 20 to 15min,which shows that a better effect of magnetization could be obtained in the condition of lower temperature and shorter time.Using biochar as reductant,iron concentrate extracted from pyrite cinder as about 64%iron grade could be produced,and the recovery is over 90% under the condition of above 90% grinding particle less than 0.045 mm and magnetic intensity of 0.124-0.194 T. 相似文献