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101.
102.
复杂样本色谱保留时间漂移自动校正方法的探讨及软件编制 总被引:5,自引:3,他引:2
建立了对色谱保留时间漂移的自动校正方法并开发了相关的软件,有效的提高对复杂色谱样本进行后续分析处理方法的效果。自动校正方法主要通过参考峰的选择和匹配,局部线性调整和容差校正实现对大量复杂色谱数据的保留时间漂移的校正。通过质谱图库的检索与匹配证实了所选择的参考峰的有效性和准确性,通过对卷烟样品数据的处理和分析,证明了应用该方法可显著的提高后续数据分析方法的效果。 相似文献
103.
In this paper, drying of button mushroom (Agaricus bisporus) slices with an innovative drying technique of hot air combined with Electrohydrodynamic (EHD) drying process was investigated at three electrode gaps (5, 6, and 7 cm) and voltage levels (17, 19, and 21 kV). The effects of different hot air combined with EHD drying treatments on the temperature of the mushroom slices, drying time, final color and protein denaturation features including enthalpy (ΔH), onset temperature (To), peak transition temperature (Tp), conclusion temperature (Tc), and temperature range (Tc–To) of endothermic peaks were systematically evaluated. In addition, water state changes in DSC cooling thermograms of dried mushroom slices were investigated. The results obtained by differential scanning calorimetry showed that the ΔH values in the DSC traces of the EHD-dried mushroom slices were reduced with a decrease in the electrode gap and an increase in the voltage. Specifically, among voltages of 21, 17, and 19 kV, a voltage of 21 kV resulted in the lowest ΔH and Tc–To values and the highest Tp and To values. This result indicated that voltage had a significant effect on these responses. Similarly, the DSC results showed a considerable effect of high electric field intensity on ΔH, Tc–To and Tp responses related to protein denaturation in comparison to low electric field intensity. 相似文献
104.
从理论上分析了机织物撕裂曲线的形成机理,找出织物撕裂曲线上与纱线滑移相关的3个指标,即,撕裂曲线的初始斜率、峰升率和峰值距.为了证实采用织物撕裂曲线的这3个指标预测其纰裂性能的可行性,织造了5种不同织纹组织、不同紧度的织物样品,研究了样品织物撕裂性能的这3个指标与其纰裂性能之间的关系.研究结果表明,织物撕裂曲线的这3个指标与该织物的纰裂性能紧密相关,采用织物的撕裂性能预测其纰裂性能完全可行. 相似文献
105.
This paper proposes a novel hybrid approach based on particle swarm optimization and local search, named PSOLS, for dynamic optimization problems. In the proposed approach, a swarm of particles with fuzzy social-only model is frequently applied to estimate the location of the peaks in the problem landscape. Upon convergence of the swarm to previously undetected positions in the search space, a local search agent (LSA) is created to exploit the respective region. Moreover, a density control mechanism is introduced to prevent too many LSAs crowding in the search space. Three adaptations to the basic approach are then proposed to manage the function evaluations in the way that are mostly allocated to the most promising areas of the search space. The first adapted algorithm, called HPSOLS, is aimed at improving PSOLS by stopping the local search in LSAs that are not contributing much to the search process. The second adapted, algorithm called CPSOLS, is a competitive algorithm which allocates extra function evaluations to the best performing LSA. The third adapted algorithm, called CHPSOLS, combines the fundamental ideas of HPSOLS and CPSOLS in a single algorithm. An extensive set of experiments is conducted on a variety of dynamic environments, generated by the moving peaks benchmark, to evaluate the performance of the proposed approach. Results are also compared with those of other state-of-the-art algorithms from the literature. The experimental results indicate the superiority of the proposed approach. 相似文献
106.
针对非合作通信中宽带码分多址(Wideband Code Division Multiple Accesss WCDMA)信号的戈尔德(Gold)序列识别问题,提出了基于优选对m序列三阶相关峰的WCDMA信号Gold序列识别方法.根据m序列三阶相关特性,推导得到Gold序列的三阶相关特性;利用m序列的移位叠加性,采用二次延迟相乘方法消除信息码和正交可变扩频因子码对Gold序列识别的影响;最后,利用信号的三阶相关函数识别Gold序列.仿真结果表明:本文算法可以有效识别WCDMA信号的Gold序列,且信号长度越长、信噪比越高,算法的正确识别概率越高. 相似文献
107.
Shuming Chen Guiping Tan Wai‐Yeung Wong Hoi‐Sing Kwok 《Advanced functional materials》2011,21(19):3785-3793
A novel yellowish‐green triplet emitter, bis(5‐(trifluoromethyl)‐2‐p‐tolylpyridine) (acetylacetonate)iridium(III) (1), was conveniently synthesized and used in the fabrication of both monochromatic and white organic light‐emitting diodes (WOLEDs). At the optimal doping concentration, monochromatic devices based on 1 exhibit a high efficiency of 63 cd A?1 (16.3% and 36.6 lm W?1) at a luminance of 100 cd m?2. By combining 1 with a phosphorescent sky‐blue emitter, bis(3,5‐difluoro‐2‐(2‐pyridyl)phenyl)‐(2‐carboxypyridyl)iridium(III) (FIrPic), and a red emitter, bis(2‐benzo[b]thiophen‐2‐yl‐pyridine)(acetylacetonate)iridium(III) (Ir(btp)2(acac)), the resulting electrophosphorescent WOLEDs show three evenly separated main peaks and give a high efficiency of 34.2 cd A?1 (13.2% and 18.5 lm W?1) at a luminance of 100 cd m?2. When 1 is mixed with a deep‐blue fluorescent emitter, 4,4′‐bis(9‐ethyl‐3‐carbazovinylene)‐1,1′‐biphenyl (BCzVBi), and Ir(btp)2(acac), the resulting hybrid WOLEDs demonstrate a high color‐rendering index of 91.2 and CIE coordinates of (0.32, 0.34). The efficient and highly color‐pure WOLEDs based on 1 with evenly separated red, green, blue peaks and a high color‐rendering index outperform those of the state‐of‐the‐art emitter, fac‐tris(2‐phenylpyridine)iridium(III) (Ir(ppy)3), and are ideal candidates for display and lighting applications. 相似文献
108.
《Ceramics International》2022,48(4):5026-5034
In this work, co-doping effects of transition (Zn) and rare-earth (La) elements on the crystalline structure, surface morphology, photoluminescence, optical and photosensing properties of NiO thin films are studied. NiO, NiO:Zn(1%), NiO:La(1%), and NiO:Zn(1%):La(1%) thin films are fabricated using the nebulizer spray pyrolysis (NSP) method. X-ray diffraction study revealed the cubic NiO structure of all the films. Photoluminescence (PL) spectra of thin films exhibit various emission peaks centered at the wavelengths of 387, 414, 437, 451, 477, and 521 nm. The optical bandgap energy (Eg) values are found to be 3.46, 3.43, 3.39 and 3.33 eV for NiO, NiO:Zn(1%), NiO:La(1%) and NiO:Zn(1%):La(1%) thin films, respectively. The fabricated (Zn, La) co-doped NiO i.e., NiO:Zn(1%):La(1%) photo-detector exhibits highest responsivity (R), external quantum efficiency (EQE) and detectivity (D*) values of 0.50AW-1, 169% and 14.5 × 109 Jones, respectively as compared to NiO, NiO:Zn(1%) and NiO:La(1%) photo-detectors. The present study revealed that the transition and rare-earth elements co-doping can be an effective approach for tuning the various physical properties of semiconducting oxide films. 相似文献
109.
The exclusion operator is a key component in separating the search territory of each population in multi-population optimisation algorithms for unconstraint continues dynamic optimisation problems (DOPs) with the aim of maintaining the overall diversity of the population and avoiding redundant search. Although extensively used by the researchers, the role of exclusion has been barely studied in detail. Therefore, in this paper, we solely study the role of exclusion as a part of multi-population methods in DOPs. For this purpose, a comprehensive review of the various exclusion strategies reported in the literature is provided. Four strategies are also introduced to reduce the shortcomings of exclusion operator. Experimental results show that proposed strategies compared to other schemes such as reinitialized midpoint check, hill-valley detection with three checkpoints, and merging information of collided populations have the same or even higher ability to improve the performance of the multi-swarm PSO algorithms in moving peaks benchmark. 相似文献
110.
温廷敦 《中北大学学报(自然科学版)》2001,22(4):294-296
目的 研究激子峰所包含的相关信息 ,为量子阱的质量检测提供依据 .方法 总结有关激子峰的研究成果 ,将其归纳成可操作的测试理论 .结果与结论 激子峰的相对强度反映量子阱生长质量 ,激子峰的位置反映内部电场分布并进一步反映应变分布 . 相似文献