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51.
James Mason Erik Lundberg Pr Jonsson Hanna Nystrm Oskar Franklin Christina Lundin Peter Naredi Henrik Antti Malin Sund Daniel
hlund 《International journal of molecular sciences》2022,23(21)
Pancreatic ductal adenocarcinoma (PDAC) is a major cause of cancer death that typically presents at an advanced stage. No reliable markers for early detection presently exist. The prominent tumor stroma represents a source of circulating biomarkers for use together with cancer cell-derived biomarkers for earlier PDAC diagnosis. CA19-9 and CEA (cancer cell-derived biomarkers), together with endostatin and collagen IV (stroma-derived) were examined alone, or together, by multivariable modelling, using pre-diagnostic plasma samples (n = 259 samples) from the Northern Sweden Health and Disease Study biobank. Serial samples were available for a subgroup of future patients. Marker efficacy for future PDAC case prediction (n = 154 future cases) was examined by both cross-sectional (ROC analysis) and longitudinal analyses. CA19-9 performed well at, and within, six months to diagnosis and multivariable modelling was not superior to CA19-9 alone in cross-sectional analysis. Within six months to diagnosis, CA19-9 (AUC = 0.92) outperformed the multivariable model (AUC = 0.81) at a cross-sectional level. At diagnosis, CA19-9 (AUC = 0.995) and the model (AUC = 0.977) performed similarly. Longitudinal analysis revealed increases in CA19-9 up to two years to diagnosis which indicates a window of opportunity for early detection of PDAC. 相似文献
52.
Richard Haley Allen Armstrong Fergus Clancy Antti Manninen John Hook Henry Hall 《Journal of Low Temperature Physics》1995,101(3-4):787-792
We have investigated transverse continuous wave NMR in a geometry where the modes are influenced by susceptibility anisotropy. The helium sample is separated by mylar foils into layers 12 m thick perpendicular to the external dc magnetic field. In this geometryl is constrained to be parallel to the field andd switches from parallel to perpendicular to the field over a small range of field around the dipole unlocking field. The mode frequencies below this critical field yield a value for the susceptibility anisotropy. Above the critical field the expected negative frequency shift is observed, as well as a positive frequency shift due to bulk material and an unexpected signal close to the Larmor frequency. 相似文献
53.
54.
The Measurement of Business Intelligence 总被引:1,自引:0,他引:1
Based on a literature review, this article identifies and assesses measurement approaches for two different purposes: determining the value of BI and managing the BI process within an organization. 相似文献
55.
Marja-Riitta Kivi Tapio Gr nfors Antti Koponen 《Behaviour & Information Technology》1998,17(3):152-154
This paper describes an efficient technique to record display output stream with memory resident software. This kind of recording can be made useful for studying text writing processes experimentally, for example programmers behaviour during coding. The system is inconspicuous in test situation and does not seem to affect the testees working. Separate software has been developed for reviewing captured sessions. 相似文献
56.
High-throughput data analysis for detecting and identifying differences between samples in GC/MS-based metabolomic analyses 总被引:9,自引:0,他引:9
Jonsson P Johansson AI Gullberg J Trygg J A J Grung B Marklund S Sjöström M Antti H Moritz T 《Analytical chemistry》2005,77(17):5635-5642
In metabolomics, the objective is to identify differences in metabolite profiles between samples. A widely used tool in metabolomics investigations is gas chromatography-mass spectrometry (GC/MS). More than 400 compounds can be detected in a single analysis, if overlapping GC/MS peaks are deconvoluted. However, the deconvolution process is time-consuming and difficult to automate, and additional processing is needed in order to compare samples. Therefore, there is a need to improve and automate the data processing strategy for data generated in GC/MS-based metabolomics; if not, the processing step will be a major bottleneck for high-throughput analyses. Here we describe a new semiautomated strategy using a hierarchical multivariate curve resolution approach that processes all samples simultaneously. The presented strategy generates (after appropriate treatment, e.g., multivariate analysis) tables of all the detected metabolites that differ in relative concentrations between samples. The processing of 70 samples took similar time to that of the GC/TOFMS analyses of the samples. The strategy has been validated using two different sets of samples: a complex mixture of standard compounds and Arabidopsis samples. 相似文献
57.
Four surveys of breath alcohol were conducted on two motorboat passages at the archipelago of the Gulf of Finland on Friday and Saturday afternoons in summer 1978. All passing motorboats were controlled by the police and the drivers were breathanalyzed with AlcolmeterR. The breath test was positive for 126 (29.7%) of 424 examined drivers. Mainly these drivers had ingested small amounts of alcohol, and in only five cases (1.2%) did the blood alcohol result exceed the statutory blood alcohol limit, which is 0.15% for motored water traffic in Finland. The present study suggest a remarkable difference in people's attitudes toward driving a motor vehicle on land or at sea in their free time after ingestion of alcohol. 相似文献
58.
The purpose of this paper is to discuss the requirements and challenges of pyrolysis oil's transportation in Finland. Pyrolysis oil is a new type of renewable liquid fuel that can be utilised in applications such as heat and electricity production. It has never been transported on a large scale in Finland. Possible options are transport by road, rail and waterway. The most significant requirements in its transportation are created by acidity and high density of pyrolysis oil, which impose requirements for the materials and transport equipment. The study described here shows that constant domestic transportation of pyrolysis oil is most reasonably operated with tank trucks. Rail-based transport may have potential for domestic fixed routes, and transport by water could be utilised in exporting. All transportation methods have limitations and advantages relative to each other. Ultimately, the production site and end-user's locations will determine the most suitable transport method. 相似文献
59.
60.
Matthias Droste Antti Jrvenp Matias Jaskari Mykhaylo Motylenko Anja Weidner Pentti Karjalainen Horst Biermann 《Fatigue & Fracture of Engineering Materials & Structures》2021,44(1):43-62
Different grain sizes were created in a metastable 17Cr‐7Mn‐7Ni steel by martensite‐to‐austenite reversion at different temperatures using a laser beam. Two fully reverted material states obtained at 990°C and 780°C exhibited average grain sizes of 7.7 and 2.7 μm, respectively. The third microstructure (610°C) consisted of grains at different stages of recrystallization and deformed austenite. A hot‐pressed, coarse‐grained counterpart was studied for reference. The yield and tensile strengths increased with refined grain size, maintaining reasonable elongation except for the heterogeneous microstructure. Total strain‐controlled fatigue tests revealed increasing initial stress amplitudes but decreasing cyclic hardening and fatigue‐induced α′‐martensite formation with decreasing grain size. Fatigue life was slightly improved for the 2.7‐μm grain size. Contrary, the heterogeneous microstructure yielded an inferior lifetime, especially at high strain amplitudes. Examinations of the cyclically deformed microstructure showed that the characteristic deformation band structure was less pronounced in refined grains. 相似文献