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101.
Chen Huan Hsu Jyh-Yih Hsieh Jia-You Hsu Hsin-Yao Chang Chia-Hao Lin Yu-Ju 《Journal of Mechanical Science and Technology》2021,35(12):5323-5333
Journal of Mechanical Science and Technology - The predictive maintenance of wind turbines has become a critical issue with the rapid development of wind power generation. The early detection of... 相似文献
102.
Chang-Hsin Hsieh 《Civil Engineering and Environmental Systems》2013,30(2):67-76
It is customary to assume a frequency distribution in flood frequency analysis. The parameters of the distribution are estimated by using observed or transformed data. The fitted distribution is then used to estimate the magnitudes of floods of different frequencies. The maximum entropy (ME) probability distribution is defined as the 'minimally prejudiced probability distribution which maximizes the entropy subject to constraints supplied by the given information'. In spite of many attractive features of the ME distribution, it has not been used in its general form in practice. The main reason for not using the ME distribution in its general form is that the parameter estimation problem associated with the ME distribution is not easy. Recently this problem has been solved and an algorithm has been developed to estimate the parameters of the ME distribution. The objective of the research reported in the present paper is to fit ME distributions to flood data. The ME distributions are compared with other well known distributions. The computational aspects and selection of orders of distributions are also discussed. The ME distribution is shown to be versatile and fits a variety of flood data very well. 相似文献
103.
Ming‐Shu Kuo Shinn‐Jen Chang Ping‐Hsun Hsieh Yuan‐Chang Huang Chia‐Chen Li 《Journal of the American Ceramic Society》2016,99(2):445-451
This article discusses the appropriate dispersant for titania (TiO2) nanopowder in organic‐based suspensions. Four types of oleyl‐based dispersants, namely, oleyl alcohol, oleic acid, oleylamine, and oleyl phosphate, which have the functional groups hydroxyl (–OH), carboxyl (–COOH), amino (–NH2), and phosphorous [–P(=O)(OH)2], respectively, were compared for their ability to disperse TiO2. Experimental results for zeta potential, adsorption, FT‐IR spectroscopy, and rheology, as well as theoretical calculations, indicate that dispersants with –P(=O)(OH)2 and –NH2 were more efficient than those with –COOH or –OH. The primary reason for this difference is related to the different interactions of TiO2 with various dispersants and to different dispersion mechanisms. In addition to the major functional groups, –OH in the chemical structure of dispersants was important, as it might have other effects such as destabilization of the suspensions. 相似文献
104.
Thermoplastic polyvinyl alcohol/multiwalled carbon nanotube composites: Preparation,mechanical properties,thermal properties,and electromagnetic shielding effectiveness 下载免费PDF全文
Jia‐Horng Lin Zheng‐Ian Lin Yi‐Jun Pan Chien‐Teng Hsieh Chien‐Lin Huang Ching‐Wen Lou 《应用聚合物科学杂志》2016,133(21)
This study uses the solution mixing method to combine plasticized polyvinyl alcohol (PVA) as a matrix, and multiwalled carbon nanotubes (MWCNTs) as reinforcement to form PVA/MWCNTs films. The films are then laminated and hot pressed to create PVA/MWCNTs composites. The control group of PVA/MWCNTs composites is made by incorporating the melt compounding method. Diverse properties of PVA/MWCNTs composites are then evaluated. For the experimental group, the incorporation of MWCNTs improves the glass transition temperature (Tg), crystallization temperature, Tc), and thermal stability of the composites. In addition, the test results indicate that composites containing 1.5 wt % of MWCNTs have the maximum tensile strength of 51.1 MPa, whereas composites containing 2 wt % MWCNTs have the optimal electrical conductivity of 2.4 S/cm, and electromagnetic shielding effectiveness (EMI SE) of ?31.41 dB. This study proves that the solution mixing method outperforms the melt compounding method in terms of mechanical properties, dispersion, melting and crystallization behaviors, thermal stability, and EMI SE. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43474. 相似文献
105.
Ting-Kai Huang Jau-Yu Chiou Ya-Chi Wang Kuo-Huang Hsieh Jiang-Jen Lin 《Journal of Polymer Research》2016,23(8):151
The organic ionic exchange intercalation of smectite clays is conventionally performed in water swelling conditions. Here we report a different mechanism for modifying the smectite clays in alcohol solvents. The modification of sodium montmorillonite with poly(oxyethylene-oxypropylene)-amines (POA-amine) were compared for the differences between in water and in alcohol. In water, the intercalation of hydrophobic poly(oxypropylene)-rich amines in the silicate galleries expands the interlayer spacing up to 10 nm and even to exfoliation (featureless in X-ray diffraction pattern) with over 5 amine equivalents, where as hydrophilic poly(oxyethylene)-rich amines could only intercalate in a low spacing of 1.8 nm. On the other hand, all of the POA-amines in isopropanol afford the exfoliation with over, 3 amine equivalents. The mechanism of this unexpected exfoliation is explained by the thermodynamic formations of an imaginary membrane surrounding the clay units, followed by amine diffusion from the solvent into the clay galleries. 相似文献
106.
Angaw Kelemework Abay Molla Bahiru Gebeyehu Hsieh Kun Lin Po Chun Lin Jiunn-Yih Lee Chang-Mou Wu Ri-Ichi Murakami Tai-Chin Chiang 《Journal of Polymer Research》2016,23(9):198
Blends of polylactide (PLA) and recycled polypropylene (rPP) were prepared by melt-processing using a corotating twin-screw extruder and subsequent pelletizing of the extrudates for injection molding. The PLA/rPP blends were characterized by Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), Dynamic Mechanical Analysis (DMA), rheometer (MCR-102), scanning electron microscopy(SEM), tensile tests, and impact measurements. The results indicate that the PLA/rPP blend is immiscible and has a two-phase structure. TGA revealed enhancement of the thermal stability of the blends upon addition of rPP. The storage modulus, loss modulus, and complex viscosity of the blends increased with rPP concentration. Mechanical studies showed that introduction of rPP results in a decrease in tensile strength and modulus and enhancement of the impact strength of PLA in the blends. The effects of a silane coupling agent on the morphology and on the tensile and impact properties of the rPP blends of silane-modified PLA were also examined. SEM studies suggest that silane is an effective interfacial modifier. Thus, better interfacial adhesion was observed with silane-modified blends as compared with unmodified blends. Silane also improved the mechanical properties of the modified blends. The blends reached maximum tensile strength at 1.5 wt.% silane (relative to modified PLA content), and impact strength increased with increasing silane concentration. These results confirm the enhancing effect of silane on modified PLA/rPP blends. 相似文献
107.
Ying-Hsien Huang Ho-Chang Kuo Fu-Chen Huang Hong-Ren Yu Kai-Sheng Hsieh Ya-Ling Yang Jiunn-Ming Sheen Sung-Chou Li Hsing-Chun Kuo 《International journal of molecular sciences》2016,17(5)
Kawasaki disease (KD) is a type of systemic vasculitis that primarily affects children under the age of five years old. For sufferers of KD, intravenous immunoglobulin (IVIG) has been found to successfully diminish the occurrence of coronary artery lesions. Anemia is commonly found in KD patients, and we have shown that in appropriately elevated hepcidin levels are related to decreased hemoglobin levels in these patients. In this study, we investigated the time period of anemia and iron metabolism during different stages of KD. A total of 100 patients with KD and 20 control subjects were enrolled in this study for red blood cell and hemoglobin analysis. Furthermore, plasma, urine hepcidin, and plasma IL-6 levels were evaluated using enzyme-linked immunosorbent assay in 20 KD patients and controls. Changes in hemoglobin, plasma iron levels, and total iron binding capacity (TIBC) were also measured in patients with KD. Hemoglobin, iron levels, and TIBC were lower (p < 0.001, p = 0.009, and p < 0.001, respectively) while plasma IL-6 and hepcidin levels (both p < 0.001) were higher in patients with KD than in the controls prior to IVIG administration. Moreover, plasma hepcidin levels were positively and significantly correlated with urine hepcidin levels (p < 0.001) prior to IVIG administration. After IVIG treatment, plasma hepcidin and hemoglobin levels significantly decreased (both p < 0.001). Of particular note was a subsequent gradual increase in hemoglobin levels during the three weeks after IVIG treatment; nevertheless, the hemoglobin levels stayed lower in KD patients than in the controls (p = 0.045). These findings provide a longitudinal study of hemoglobin changes and among the first evidence that hepcidin induces transient anemia and hypoferremia during KD’s acute inflammatory phase. 相似文献
108.
Hsun-Shuo Chang Chu-Hung Lin Yi-Shuan Chen Hui-Chun Wang Hing-Yuen Chan Sung-Yuan Hsieh Ho-Cheng Wu Ming-Jen Cheng Gwo-Fang Yuan Shan-Yu Lin Yue-Jin Lin Ih-Sheng Chen 《International journal of molecular sciences》2016,17(9)
Fractionation of an EtOAc-soluble fraction of the solid fermentate of an endophytic fungus, Lachnum abnorme Mont. BCRC 09F0006, derived from the endemic plant, Ardisia cornudentata Mez. (Myrsinaceae), resulted in the isolation of three new chromones, lachnochromonins D–F (1–3), one novel compound, lachabnormic acid (4), along with nine known compounds (5–13). Their structures were elucidated by spectroscopic analyses. Alternariol-3,9-dimethyl ether (6) was given the correct data as well as 2D spectral analyses for the first time. This is the first report of the isolation of one unprecedented compound 4 from Lachnum genus, while all known compounds were also found for the first time from Lachnum. The effects of some isolates (3, 4, 7–9, 10, and 13) on the inhibition of nitric oxide (NO) production in lipopolysaccharide (LPS)-activated RAW 264.7 murine macrophages were also evaluated. Several compounds exhibited weak inhibitory activity on lipopolysaccharide (LPS)-stimulated NO production in RAW 264.7 macrophages. 相似文献
109.
Wenjea J. Tseng Chia‐Chin Cheng J. H. Hsieh 《Journal of the American Ceramic Society》2014,97(2):407-412
A structural design featuring rattle‐type silver/titania (Ag/TiO2) core/shell, that is, Ag@TiO2, composite microcapsules is produced. The TiO2 shell protects the encapsulated, movable Ag nanoparticles from breaking away under moderate loading, minimizing hence adverse environmental and biological exposure due to the metal loss, whereas the mesoporous shell serves as conduits for Ag ions released from the caged Ag nanoparticles to kill Escherichia coli in aqueous solutions under dark condition. The anatase TiO2 shell imparts an additional, synergistic photocatalysis activity under ultraviolet irradiation. A pronouncedly enhanced photocatalysis activity results when the Ag@TiO2 composite capsules were thermally annealed under vacuum. This “rattle‐in‐ball” hybrid architecture enables bifunctional bactericide and photocatalysis capability under both light and dark conditions, as well as mitigated environmental and biological impact in practical use. 相似文献
110.
Lu Shen Yusheng Zhao Ali Tekeei Fu‐Hung Hsieh Galen J. Suppes 《Polymer Engineering and Science》2014,54(7):1503-1511
A model based on about a dozen fundamental differential equations is used to evaluate and simulate the urethane reactions and physical processes of urethane box foaming. This work focuses on quantitative modeling of foam density for foams using water and physical blowing agents. The final densities of foams range from 30 to 90% of the density as projected with full utilization of the blowing agent. The primary sources of inefficient use of blowing agent are loss of the physical blowing during open‐air mixing and degassing—basically, physical blowing agents with boiling points between 25 and 80°C will evaporate and experience cell rupture in box foams. This loss of blowing agent would not apply to in‐line mixers used for commercial production and should be taken into account with scaling up box or cup foams commercial processes. POLYM. ENG. SCI., 54:1503–1511, 2014. © 2013 Society of Plastics Engineers 相似文献