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61.
Some properties such as hardness and fracture toughness of boride formed on the 99.97 wt% pure iron were investigated. Boronizing was carried out in a solid medium, consisting of Ekabor powders of 5% B4C as donor, 5% KBF4 as an activator and 90% SiC as diluent at 800 °C for 2, 4 and 8 h. The dominant phase formed on the substrate was found to be Fe2B that had a finger-like shape morphology. The hardness of boride on the 99.97% pure iron was over 1700HVN, while the hardness of pure iron was about 130HVN. It was found that the fracture toughness of boride formed on surfaces of 99.97% pure iron, depending on the process time, ranged from 3.59 to 3.83 MPa m1/2. Depending on process time and temperature, the depth of the boride layer ranges from 22 to 43 μm, leading to a diffusion-controlled process. 相似文献
62.
63.
M Co?kun AM A?ildere F Boyvat C Tarhan EA Niron 《Canadian Metallurgical Quarterly》1998,8(8):1425-1428
In this report we present the CT findings of two non-gestational, extragonadal choriocarcinomas, one arising within the stomach and one in the pancreas. These are rare tumours and a pancreatic primary site has not been previously described. 相似文献
64.
Single fiber action potentials (SFAPs) from peripheral nerves, such as recorded with cuff electrodes, can be modelled as the convolution of a source current and a weight function that describes the recording electrodes and the surrounding medium. It is shown that for cuff electrodes, the weight function is linearly scaled with the action potential (AP) velocity and that it is, therefore, possible to implement a model of the recorded SFAPs based on a wavelet multiresolution technique (filterbank), where the wavelet scale is proportional to the AP velocity. The model resulted in single fiber action potentials matching the results from other models with a goodness of fit exceeding 0.99. This formulation of the SFAP may serve as a basis for model-based wavelet analysis and for advanced cuff design. 相似文献
65.
Nazim Sekeroglu Faruk Ozkutlu S Metin Kara Mensure Ozguven 《Journal of the science of food and agriculture》2008,88(1):86-90
BACKGROUND: Medicinal plants commonly used and traded in Turkey were monitored for their cadmium and selected micronutrient (copper, iron, manganese and zinc) content. RESULTS: Cadmium was not detected in any sample of licorice extract, linden flowers or nettle leaves. However, in the rest of the samples, cadmium was found in the range of 7–126 µg kg?1, with the highest concentration in chamomile leaf. Of all the monitored trace elements, the highest concentration found was 520 mg kg?1 iron in zahter. The highest copper, manganese and zinc concentrations were found in rose hips (24 mg kg?1), Turkish oregano (58 mg kg?1) and zahter (50 mg kg?1), respectively. CONCLUSION: The results of the present study reveal that cadmium and trace element concentrations in medicinal plants commonly used as traditional medicines in Turkey are well below the critical levels. Copyright © 2007 Society of Chemical Industry 相似文献
66.
The present investigation was to evaluate the antioxidant and antibacterial activities of hexane and methanol extracts from
Origanum vulgare ssp. hirtum and Thymus vulgaris (Komotini, Greece). The methanol extracts of oregano and thyme against DPPH radical were more active than the hexane extracts
(mean values 0.94 and 0.47, respectively) and oregano exhibited stronger activity than thyme (mean values 0.82 and 0.55, respectively).
The results from the β-carotene/linoleic acid assay showed that all plant extracts inhibited linoleic acid oxidation up to
70.78±1.17%. The oregano extracts exhibited the strongest inhibition against Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus using the disc diffusion assay. The chemical composition of the hexane and methanol extracts, by using GC-MS, showed that
carvacrol, thymol, and p-cymene were the most prominent compounds. The methanol extract of oregano was found the most potent
antioxidant with the highest content of total phenolics (138.92 mg GA/g extract) and carvacrol (76.7%). 相似文献
67.
Hürmüs Gürsu Yamur Güner Kamil Burak Dermenci Metin Genten Ahmet Furkan Bulu Umut Savac Servet Turan Yücel ahin 《国际能源研究杂志》2019,43(10):5346-5354
Nowadays, doped graphenes are attracting much interest in the field of Li‐ion batteries since it shows higher specific capacity than widely used graphite. However, synthesis methods of doped graphenes have secondary processes that requires much energy. In this study, in situ synthesis of N‐doped graphene powders by using of cyclic voltammetric method from starting a graphite rod in nitric acid solution has been discussed for the first time in the literature. The N‐including functional groups such as nitro groups, pyrrolic N, and pyridinic N have been selectively prepared as changing scanned potential ranges in cyclic voltammetry. The electrochemical performance as anode material in Li‐ion batteries has also been covered within this study. N‐doped graphene powders have been characterized by electrochemical, spectroscopic, and microscopic methods. According to the X‐ray photoelectron spectroscopy and Raman results, N‐doped graphene powders have approximately 16 to 18 graphene rings in their main structure. The electrochemical analysis of graphene powders synthesized at different potential ranges showed that the highest capacity was obtained 438 mAh/g after 10 cycles by using current density of 50 mA/g at N‐GP4. Furthermore, the sample having higher defect size shows better specific capacity. However, the more stable structure due to oxygen content and less defect size improves the rate capabilities, and thus, the results obtained at high current density indicated that the remaining capacity of N‐GP1 was higher than the others. 相似文献
68.
69.
Faruk Serin Metin Erturkler 《International journal of imaging systems and technology》2020,30(2):311-326
The cell is the smallest unit of living beings, which has structural and functional properties. Almost all cell behaviors are regulated by various intracellular reactions initiated by the signaling. The signaling and the distance between cells influence each other. Thus, cell-location-based modeling and analyzing of histopathological tissues provide important information to the expert. In literature, methods such as distance-based threshold, K-Nearest Neighbor, Voronoi graphs, Delaunay triangulation, and colored graph have been used. However, circular neighborhood relationships of cells have not been considered by any CAD system so far despite of its crucial impact. Thus, we developed the circular neighborhood cell-graph. Histopathological images of liver were classified by using features extracted from T-Distance, K-Nearest Neighbor, Voronoi, Delaunay, and the proposed cell-graph. Then, the classification performances of the methods were compared. Experimental results show that liver tissue images can be classified with accuracy of 95.7% by using the features provided by the proposed cell-graph model. 相似文献
70.
Ozer Caglar Ebeoglugil M. Faruk Yildirim Serdar Nil Metin 《Journal of Materials Science: Materials in Electronics》2022,33(3):1511-1528
Journal of Materials Science: Materials in Electronics - In this study, ITO-coated PET was used as the substrate to create a flexible and transparent structure. a-IGZO (amorphous InGaZnO4) is... 相似文献