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91.
Turhan S Arıkan IH Oğuz F Özdemir T Yücel B Varinlioğlu A Köse A 《Radiation protection dosimetry》2012,148(1):45-50
Natural background gamma radiation was measured along roads in the environs of ?anakkale region by using a car-borne spectrometer system with a plastic gamma radiation detector. In addition, activity concentrations of 23?U, 22?Ra, 232Th and ??K in soil samples from the ?anakkale region were determined by using a gamma spectrometer with an HPGe detector. A total of 92,856 data of the background gamma dose rate were collected for the ?anakkale region. The background gamma dose rate of the ?anakkale region was mapped using ArcGIS software, applying the geostatistical inverse distance-weighted method. The average and population-weighted average of the gamma dose are 55.4 and 40.6 nGy h?1, respectively. The corresponding average annual effective dose to the public ranged from 26.6 to 96.8 μSv. 相似文献
92.
J. Reinoso A. Blázquez A. Estefani F. París J. Cañas E. Arévalo F. Cruz 《Composites Part B》2012,43(4):1929-1942
A specimen is studied in order to analyse the stringer runout effect in a specific design. An experimental test was carried out in several stages until specimen collapse, allowing the damaged regions and their characteristic geometric dimensions to be identified by ultrasound inspections. Several numerical analyses based on finite element method of the component were performed using the commercial software ABAQUS. These numerical analyses aimed to study in detail the onset and propagation of damage in the skin-stringer joint during the load procedure. Due to the high computational cost that this kind of procedure usually requires, a global–local approach was performed, comparing the two techniques offered by the software ABAQUS: Submodeling and Shell-to-Solid Coupling. Shell element typology was used in both cases for the global model. In order to estimate the extension of the critical zone in the specimen, the adhesive layer was modeled by means of solid elements. With reference to the local analysis, laminate continuum elements were selected to discretize the skin and the stringer, whereas the adhesive was represented by interface cohesive elements to take the damage evolution into account. A final correlation was carried out between numerical predictions and experimental results of the damaged regions in the component at several load levels. 相似文献
93.
Quadruple-effect evaporator units are commonly used in food focus area in sector is evaporative unit. It consumes about 60% of total energy input. The present study evaluates the performance of quadruple-effect evaporator unit (QEEU) by using exergy analysis based on actual operational data. A tomato paste factory is chosen for the analysis. The highest exergy destruction/loss occurs in the first effect with 158.2 kW, 52.7% of exergy input in first effect. Steam temperature should be decreased in order to decrease exergy destruction in first effect. Also, third effect achieves the highest exergy efficiency with 93.3%. Exergetic improvement potential of each effect varies between 0.3 kW and 83.6 kW. The highest and lowest exergetic improvement potential occurs in first and third effect of QEEU system, respectively. Exergetic improvement potential is equals to 52.80%, 11.10%, 6.73% and 69.8% of exergy loss/destruction from the first effect to the last effect, respectively. Total exergetic improvement potential is achieved as 128 kW (55% of total exergy loss/destruction) in QEEU system. It is expected that analyses result provide important information for designer and/or resources of multiple effect evaporator unit. 相似文献
94.
95.
The Mediterranean Diet decreases LDL atherogenicity in high cardiovascular risk individuals: a randomized controlled trial 下载免费PDF全文
Álvaro Hernáez Olga Castañer Alberto Goday Emilio Ros Xavier Pintó Ramón Estruch Jordi Salas‐Salvadó Dolores Corella Fernando Arós Lluis Serra‐Majem Miguel Ángel Martínez‐González Miquel Fiol José Lapetra Rafael de la Torre M. Carmen López‐Sabater Montserrat Fitó 《Molecular nutrition & food research》2017,61(9)
96.
Cell transplantation into the seminiferous tubules is a useful technique for the study of physiological and pathological conditions affecting the testis. However, the precise three-dimensional organization and, particularly, the complex connectivity of the seminiferous network have not yet been thoroughly characterized. To date, the technical approaches to address these issues have included manual dissection under the stereomicroscope, reconstruction of histological serial sections, and injection of contrast dyes, but all of them have yielded only partial information. Here, using an approach based on the microinjection of a self-polymerizing resin followed by chemical digestion of the surrounding soft tissues, we reveal fine details of the seminiferous tubule scaffold and its connections. These replicas of the testis seminiferous network were studied by scanning electron microscopy. The present results not only establish a morphological basis for more precise microinjection into the mouse seminiferous tubules but also enable a more profound investigation of physiological and embryological features of the testis. 相似文献
97.
Sheila Romo-Sánchez María Arévalo-Villena Esteban García Romero Héctor L. Ramirez Ana Briones Pérez 《Food and Bioprocess Technology》2014,7(5):1381-1392
Enzyme immobilization is becoming more widely practised in biotechnology because of the advantages that this method brings. In this study, commercial β-glucosidase for aroma released in winemaking was immobilized on diverse supports (alginate–chitin, chitosan–chitin) by using different methods. It was found that the most appropriate matrix was chitosan by adsorption and reticulation. The optimal immobilization conditions were pH 3.5, immobilization time 120 min, and concentration of cross-linker glutaraldehyde 0.25 %. Stability of the immobilized enzymes was assessed, which revealed a number of advantages, such as a lower enzyme dose required for immobilization (367 times lower than the free enzyme dose recommended by the manufacturer), high stability over time, and reusability. In vitro studies of cellobiose and in vivo studies of wine and aroma precursors isolated from grape must yielded similar outcomes with respect to enzyme hydrolysis of free and immobilized proteins. 相似文献
98.
Bahcebasi S Kocyigit I Akyol L Unal A Sipahioğlu MH Oymak O Utas C 《Hemodialysis international. International Symposium on Home Hemodialysis》2011,15(2):284-287
Central venous catheterization is frequently performed for perioperative management and long-term intravenous access. Although complications associated with central venous catheter insertion have been widely reported, there are few reports of carotid-jugular arteriovenous fistula formation. Endovascular procedures are associated with a risk of immediate and delayed thromboembolic and ischemic complications. We describe a case of a carotid-jugular arteriovenous fistula and a cerebrovascular infarct following the insertion of a double-lumen catheter for hemodialysis access. We provide recommendations for the prevention and the early detection of this iatrogenic complication. 相似文献
99.
F??bio da Silva Lisboa Gregorio Guadalupe Carbajal Ar??zaga Fernando Wypych 《Topics in Catalysis》2011,54(8-9):474-481
Layered lanthanum and copper(II) laurates were tested as catalysts for methanolic esterification of lauric acid (C12). Factorial design evidenced a positive effect of reaction temperature and amount of catalyst on ester conversion, while the acid:alcohol molar ratio (MR) had a negative effect. With lanthanum laurate, 90.5% conversion was reached at 140???C with 10% catalyst and MR of 6:1. Although the highest conversion with copper(II) laurate converted 81.5% under the same conditions, results were better with a lower amount of catalyst (78% ester at 140???C with 2% catalyst and MR of 6:1). A calcium hydroxide succinate was also investigated showing better catalytic performance than the well-known CaO, under mild reaction conditions (120???C with 1% catalyst and MR of 3:1). Although layered carboxylates can be successively reused, the layered calcium hydroxide salt transformed into inactive CaCO3 in the second reuse reaction. 相似文献
100.
Boulaiz H Alvarez PJ Prados J Marchal J Melguizo C Carrillo E Peran M Rodríguez F Ramírez A Ortíz R Aránega A 《International journal of molecular sciences》2011,12(11):7445-7458
Breast cancer research has developed rapidly in the past few decades, leading to longer survival times for patients and opening up the possibility of developing curative treatments for advanced breast cancer. Our increasing knowledge of the biological pathways associated with the progression and development of breast cancer, alongside the failure of conventional treatments, has prompted us to explore gene therapy as an alternative therapeutic strategy. We previously reported that gef gene from E. coli has shown considerable cytotoxic effects in breast cancer cells. However, its action mechanism has not been elucidated. Indirect immunofluorescence technique using flow cytometry and immunocytochemical analysis were used to detect breast cancer markers: estrogen (ER) and progesterone (PR) hormonal receptors, human epidermal growth factor receptor-2 proto-oncogene (c-erbB-2), ki-67 antigen and p53 protein. gef gene induces an increase in ER and PR expressions and a decrease in ki-67 and c-erbB-2 gene expressions, indicating a better prognosis and response to treatment and a longer disease-free interval and survival. It also increased p53 expression, suggesting that gef-induced apoptosis is regulated by a p53-mediated signaling pathway. These findings support the hypothesis that the gef gene offers a new approach to gene therapy in breast cancer. 相似文献