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51.
High strength compacted graphite iron (CGI) or alloyed cast iron components are substituting previously used non-ferrous castings in automotive power train applications.The mechanical engineering industry has recognized the value in substituting forged or welded structures with stiff and light-weight cast iron castings.New products such as wind turbines have opened new markets for an entire suite of highly reliable ductile iron cast components.During the last 20 years,casting process simulation has developed from predicting hot spots and solidification to an integral assessment tool for foundries for the entire manufacturing route of castings.The support of the feeding related layout of the casting is still one of the most important duties for casting process simulation.Depending on the alloy poured,different feeding behaviors and self-feeding capabilities need to be considered to provide a defect free casting.Therefore,it is not enough to base the prediction of shrinkage defects solely on hot spots derived from temperature fields.To be able to quantitatively predict these defects,solidification simulation had to be combined with density and mass transport calculations,in order to evaluate the impact of the solidification morphology on the feeding behavior as well as to consider alloy dependent feeding ranges.For cast iron foundries,the use of casting process simulation has become an important instrument to predict the robustness and reliability of their processes,especially since the influence of alloying elements,melting practice and metallurgy need to be considered to quantify the special shrinkage and solidification behavior of cast iron.This allows the prediction of local structures,phases and ultimately the local mechanical properties of cast irons,to asses casting quality in the foundry but also to make use of this quantitative information during design of the casting.Casting quality issues related to thermally driven stresses in castings are also gaining increasing attention.State-of-the-art tools allow the prediction of residual stresses and iron casting distortion quantitatively.Cracks in castings can be assessed,as well as the reduction of casting stresses during heat treatment.As the property requirements for cast iron as a material in design strongly increase,new alloys and materials such as ADI might become more attractive,where latest software developments allow the modeling of the required heat treatment.Phases can be predicted and parametric studies can be performed to optimize the alloy dependent heat treatment conditions during austenitization,quenching and ausferritization.All this quantitative information about the material’s performance is most valuable if it can be used during casting design.The transfer of local properties into the designer’s world,to predict fatigue and durability as a function of the entire manufacturing route,will increase the trust in this old but highly innovative material and will open new opportunities for cast iron in the future.The paper will give an overview on current capabilities to quantitatively predict cast iron specific defects and casting performance and will highlight latest developments in modeling the manufacture of cast iron and ADI as well as the prediction of iron casting stresses. 相似文献
52.
Leonie Roland Vanessa Schweinzer Peter Kanz Georg Sattlecker Florian Kickinger Laura Lidauer Alexandra Berger Wolfgang Auer Julia Mayer Valentin Sturm Dmitry Efrosinin Sandra Breitenberger Marc Drillich Michael Iwersen 《Journal of dairy science》2018,101(11):10421-10427
The objectives of this study were (1) to develop an algorithm for the acceleration sensor of the Smartbow Eartag (Smartbow GmbH, Weibern, Austria) to distinguish between postures (lying and standing or locomotion) and to detect 6 kinds of activities (milk intake, water intake, solid feed intake, ruminating, licking or sucking without milk intake, and other activities) in dairy calves and (2) to evaluate this sensor for identifying these behaviors in dairy calves compared with observations from video. Accelerometers were applied to the left ears of 15 preweaned Holstein dairy calves. Calves were kept in a group pen and received milk replacer from an automatic calf feeder. Based on 38 h of acceleration data and video observation, an algorithm was established to detect the predefined behaviors. Using cross-validation, video recordings were used to analyze whether a behavior was detected correctly by the developed algorithm. For posture, sensitivity (94.4%), specificity (94.3%), precision (95.8%), and accuracy (94.3%) were high. Cohen's kappa was calculated as 0.88. For the 6 defined activities, overall (i.e., aggregated for all activities) accuracy was 70.8% and kappa was calculated as 0.58. Some activities (e.g., ruminating, feed intake, other activities) were identified better than others. In conclusion, the developed algorithm based on the acceleration data of the Smartbow Eartag was successful in detecting lying behavior, rumination, feed intake, and other activities in calves, but further development of the underlying algorithm will be necessary to produce reliable results for milk and water intake. 相似文献
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54.
The ability of the "conceptual-area" scoring system to differentiate between tuberculous, process schizophrenic, reactive schizophrenic, and brain-damaged patients was tested by administering the Object Sorting Test to 125 hospitalized veterans. The diagnostic groups were equivalent in mean education, intelligence, and length of hospitalization, but the tuberculous and brain-damaged patients averaged 8 yr. older than the schizophrenics. None of the scores differentiated the groups at the .05 level. In discussing these results, it was maintained that, contrary to comment in the literature, "conceptual area" has never conclusively differentiated, in a simultaneous comparison, between nonpsychiatric, brain-damaged, and schizophrenic patients, and may not be appropriate for this purpose. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
Christoph-Michael H?nel Corinna Jüptner Karen Lorenz Peter Seulen Klaus-Dietrich Sturm Holger-Jürgen B?rner 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2011,1(6):497-501
Im Folgenden wird über die Chronologie der Ereignisse im Rahmen des EHEC O104:H4 Ausbruchsgeschehen aus Sicht der Lebensmittelüberwachung
in Schleswig-Holstein bis zur Gründung der nationalen Task Force EHEC berichtet. Am Beispiel des Kreises Schleswig-Flensburg
wird die Zusammenarbeit und der Informationsaustausch zwischen Gesundheitsbeh?rde und Lebensmittelüberwachung dargestellt.
Die erste Information über einen Anstieg an Erkrankungen mit blutigem Durchfall und HUS-Symptomatik in den Kreisen anliegend
an und aus Hamburg erhielt das Ministerium für Landwirtschaft, Umwelt und l?ndliche R?ume des Landes Schleswig-Holstein am
19. Mai 2011. Der Fachdienst Veterin?rmedizin und Verbraucherschutz des Kreises Schleswig-Flensburg wurde ebenfalls am 19.
Mai 2011 über eine solche H?ufung im Kreis Schleswig-Flensburg in Kenntnis gesetzt. Daraufhin wurden auf Landes- und Kreisebene
Ma?nahmen eingeleitet, um zusammen mit den Gesundheitsbeh?rden diesen lebensmittelassoziierten Ausbruch aufzukl?ren. Am 01.
Juni 2011 fand erstmalig in Schleswig-Holstein eine Telefonkonferenz zwischen den betroffenen Ministerien und allen Lebensmittelüberwachungs-
und Gesundheitsbeh?rden der Kreise und kreisfreien St?dte statt, um das weitere Vorgehen gemeinsam zu koordinieren. Am 03.
Juni 2011 wurde in Berlin am Bundesamt für Verbraucherschutz und Lebensmittelsicherheit (BVL) die nationale Task Force EHEC
gegründet. Zwei Wochen nachdem die Gesundheitsbeh?rden von geh?uften und l?nderübergreifenden Erkrankungsf?llen Kenntnis hatten,
geht damit die Koordinierung der Aufkl?rung von den Gesundheitsbeh?rden auf das BVL über. Am 07. Juni 2011 wurde durch das
MLUR ein Mitarbeiter des Kreises Schleswig-Flensburg als Vertreter für Schleswig-Holstein in die Task-Force EHEC nach Berlin
entsandt. Als Ergebnis ist aus diesem Erkrankungsgeschehen auch die Lehre zu ziehen, dass vermehrt pflanzliche Lebensmittel
zu den „gef?hrlichen Lebensmitteln“ geh?ren. Diese müssen in Zukunft viel st?rker in den Fokus genommen werden. 相似文献
56.
Benjamin W. Sturm Nerine J. CherepyOwen B. Drury Peter A. ThelinScott E. Fisher Stephen A. PayneArnold Burger Lynn A. BoatnerJoanne O. Ramey Kanai S. ShahRastgo Hawrami 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,652(1):242-246
Recent renewed emphasis placed on gamma-ray detectors for national security purposes has motivated researchers to identify and develop new scintillator materials capable of high energy resolution and growable to large sizes. We have discovered that SrI2(Eu) has many desirable properties for gamma-ray detection and spectroscopy, including high light yield of ∼90,000 photons/MeV and excellent light yield proportionality. We have measured <2.7% FWHM at 662 keV with small detectors (<1 cm3) in direct contact with a photomultiplier tube, and ∼3% resolution at 662 keV is obtained for 1 in.3 crystals. Due to the hygroscopic nature of SrI2(Eu), similar to NaI(Tl), proper packaging is required for field use. This work describes a systematic study performed to determine the key factors in the packaging process to optimize performance. These factors include proper polishing of the surface, the geometry of the crystal, reflector materials and windows. A technique based on use of a collimated 137Cs source was developed to examine light collection uniformity. Employing this technique, we found that when the crystal is packaged properly, the variation in the pulse height at 662 keV from events near the bottom of the crystal compared to those near the top of the crystal could be reduced to <1%. This paper describes the design and engineering of our detector package in order to improve energy resolution of 1 in.3-scale SrI2(Eu) crystals. 相似文献
57.
Nicole Altvater-Mackensen Gregor Balicki Lucie Bestakowa Bianca Bocatius Johannes Braun Lars Brehmer Verena Brune Kirstina Eigemeier F&#;sun Erdem Ralf Fritscher Anne Jacobs Bernd Klingsporn Marcin Kosinski Julia Kuntze Ju-Ra Lee Anna Osterhage Martin Probost Thorsten Risch Tobias Schmitt Wolfgang G. Stock Anja Sturm Katrin Weller Kerstin Werner 《Scientometrics》2005,63(3):463-529
Summary We operationalize scientific output in a region by means of the number of articles (as in the SciSearch database) per year and technology output by means of the number of patent applications (as in the database of the European Patent Office) per priority year. All informetric analyses were done using the DIALOG online-system. The main research questions are the following: Which scientific and technological fields or topics are most influent within a region and which institutions or companies are mainly publishing articles or holding patents? Do the distributions of regional science and technology fields and of publishing institutions follow the well-known informetric function? Are there - as it is expected - only few fields and few institutions which dominate the region? Is there a connection between the economic power of a region and the regional publication and patent output? Examples studied in detail are seven German regions: Aachen, Düsseldorf, Hamburg, Köln (Cologne), Leipzig - Halle - Dessau, München (Munich), and Stuttgart. Three different indicators were used, science and technology attraction of a region (number of scientific articles and patents), science and technology intensity (articles and patents per 1,000 inhabitants), and science and technology density (articles and patents per 1 billion EURO gross value added). Top region concerning both attraction and intensity is Munich, concerning density it is Aachen. 相似文献
58.
A Pillay H Liu CY Chen B Holloway AW Sturm B Steiner SA Morse 《Canadian Metallurgical Quarterly》1998,25(8):408-414
PURPOSE: Psychosocial distress and patient attitude towards psychosocial support as well as the correlations with clinical and sociodemographic characteristics should be assessed. METHODS: The stress due to cancer was measured in a consecutive sample of tumor patients at the start of radiotherapy (n = 117) by use of the Hornheide Questionnaire. In addition, the interest of these patients in professional psychosocial support was assessed with the help of the Questionnaire for Psychosocial Support. RESULTS: Patients in the course of radiotherapy and patients with a poor prognosis and advanced disease were more strongly distressed. 32.7% of patients wished professional psychosocial support from the oncologist treating them, 40.6% of the patients wished support from the oncologist and additionally from a psychotherapist or social worker. Interest in professional psychosocial support correlated with the amount of distress, but not with sociodemographic variables. CONCLUSIONS: Results stress the importance of training programs for oncologists in order to improve their ability to detect psychosocial distress in cancer patients and to offer adequate emotional support to them. 相似文献
59.
60.
Cai M Zhao Z Yin Z Ahrens L Huang P Cai M Yang H He J Sturm R Ebinghaus R Xie Z 《Environmental science & technology》2012,46(2):661-668
Perfluoroalkyl compounds (PFCs) were determined in 22 surface water samples (39-76°N) and three sea ice core and snow samples (77-87°N) collected from North Pacific to the Arctic Ocean during the fourth Chinese Arctic Expedition in 2010. Geographically, the average concentration of ∑PFC in surface water samples were 560 ± 170 pg L(-1) for the Northwest Pacific Ocean, 500 ± 170 pg L(-1) for the Arctic Ocean, and 340 ± 130 pg L(-1) for the Bering Sea, respectively. The perfluoroalkyl carboxylates (PFCAs) were the dominant PFC class in the water samples, however, the spatial pattern of PFCs varied. The C(5), C(7) and C(8) PFCAs (i.e., perfluoropentanoate (PFPA), perfluoroheptanoate (PFHpA), and perfluorooctanoate (PFOA)) were the dominant PFCs in the Northwest Pacific Ocean while in the Bering Sea the PFPA dominated. The changing in the pattern and concentrations in Pacific Ocean indicate that the PFCs in surface water were influenced by sources from the East-Asian (such as Japan and China) and North American coast, and dilution effect during their transport to the Arctic. The presence of PFCs in the snow and ice core samples indicates an atmospheric deposition of PFCs in the Arctic. The elevated PFC concentration in the Arctic Ocean shows that the ice melting had an impact on the PFC levels and distribution. In addition, the C(4) and C(5) PFCAs (i.e., perfluorobutanoate (PFBA), PFPA) became the dominant PFCs in the Arctic Ocean indicating that PFBA is a marker for sea ice melting as the source of exposure. 相似文献