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91.
Tobias?MettlerEmail authorView authors OrcID profile Michaela?Sprenger Robert?Winter 《欧洲信息系统杂志》2017,26(5):451-468
Changing demands in society and the limited capabilities of health systems have paved the way for robots to move out of industrial contexts and enter more human-centered environments such as health care. We explore the shared beliefs and concerns of health workers on the introduction of autonomously operating service robots in hospitals or professional care facilities. By means of Q-methodology, a mixed research approach specifically designed for studying subjective thought patterns, we identify five potential end-user niches, each of which perceives different affordances and outcomes from using service robots in their working environment. Our findings allow for better understanding resistance and susceptibility of different users in a hospital and encourage managerial awareness of varying demands, needs, and surrounding conditions that a service robot must contend with. We also discuss general insights into presenting the Q-methodology results and how an affordance-based view could inform the adoption, appropriation, and adaptation of emerging technologies. 相似文献
92.
Cyril Brom Vít Šisler Michaela Slussareff Tereza Selmbacherová Zdeněk Hlávka 《International Journal of Computer-Supported Collaborative Learning》2016,11(3):313-348
Despite the alleged ability of digital game-based learning (DGBL) to foster positive affect and in turn improve learning, the link between affectivity and learning has not been sufficiently investigated in this field. Regarding learning from team-based games with competitive elements, even less is known about the relationship between competitiveness (as a dispositional trait) and induced positive affect. In this media comparison study with between-subject design, participants (N?=?325; high school and college students) learned about the EU’s policy agenda by means of a debate-based method delivered through one of three educational media: a) through a social role-playing game with competitive elements played on computers, b) through a very similar game played without computers and c) through a non-game workshop. Unlike many previous DGBL studies, this study used participant randomization and strived to address the teacher effect and the length of exposure effect, while also using the same learning materials and a very similar educational method for all three treatments. Both games induced comparatively higher generalized positive affect and flow. Participants also learned more with the games. Positive affect, but not flow, mediated the influence of educational media on learning gains. Participants’ competitiveness was partly related to positive affect and experiencing flow but unrelated to learning gains. These outcomes held both when the game was played using computers, as well as without them. The study indicates that the ability of an educational intervention to instigate positive affect is an important feature that should be considered by educational designers. 相似文献
93.
94.
Michaela N. Ess 《Aerosol science and technology》2019,53(1):29-44
Flame-generated soot from miniCAST burners is increasingly being used in academia and industry as engine exhaust soot surrogate for atmospheric studies and instrument calibration. Previous studies have found that elemental carbon (EC) content of miniCAST soot is proportional to the mean particle size. Here, the characterization of a prototype miniCAST generator (5201 Type BC), which was designed to decouple the soot composition from the particle size and produce soot particles with high EC and BC content in a large size range, is reported. This prototype may operate either in a diffusion-flame or a partially premixed-flame mode, an option that was not available in former models. It was confirmed that soot properties, such as EC content and Ångström absorption exponent (AAE), were linked to the overall flame composition. In particular, combustion under fuel-rich conditions provided particles with size coupled to the EC fraction and AAE, i.e. smaller particles exhibited a lower EC fraction and higher AAE. In contrast, with fuel-lean diffusion flames and especially with premixed flames under near overall stoichiometric conditions small particles (down to 30?nm) with high EC/TC ratios (>60%) and low AAE (≈1.4) could be generated even without any thermal after-treatment. This new source might thus serve in the future as a useful surrogate for engine exhaust emissions and help to improve calibration procedures of common aerosol instruments.
Copyright © 2018 The Author(s). Published with license by Taylor & Francis Group, LLC 相似文献
95.
Šachlová Šárka Kuchařová Aneta Pertold Zdeněk Přikryl Richard Fridrichová Michaela 《Bulletin of Engineering Geology and the Environment》2017,76(1):133-144
Bulletin of Engineering Geology and the Environment - The alkali silica reaction (ASR), which originates in highly alkaline conditions in concrete where reactive forms of silica are available,... 相似文献
96.
Lars Niemann Sabine Martin Michaela Golle Heiko Schneider Bernd Stein Rudolf Pfeil Roland Solecki 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2013,8(4):381-388
A correct estimate of dermal absorption of the contained active ingredients is needed for the health risk assessment of plant protection and biocidal products. In this paper, the approach is reported that is currently taken by the Federal Institute for Risk Assessment to derive the dermal absorption rate of active substances in plant protection or biocidal products, depending on the available data. It is explained what use is made of two new guidance documents that were recently released by EFSA and OECD. Basic principles of the assessment of dermal absorption studies are described but also opportunities for estimations in the absence of product-specific experimental data. This publication is considered a first step towards harmonisation of assessment in the authorisation processes for plant protection and biocidal products. 相似文献
97.
Ceramic membranes can serve as viable alternatives to the less mechanically stable polymeric membranes utilized in microbial fuel cells (MFCs). In this work, a series of polymer-derived ceramic (PDC) proton exchange composite membranes with large ion exchange capacity (IEC) values, high cation transport numbers, and low oxygen diffusion coefficients have been synthesized at various pyrolysis temperatures using a pressing technique. These materials were composed of a polysiloxane matrix mixed with proton-conducting fillers such as montmorillonite and H3PMo12O40/SiO2 at different ratios. By tuning the average pore sizes of the membranes between 0.1 and 1?µm and their hydrophilic/hydrophobic characteristics, the maximum IEC of 0.6072 mequiv/g and cation transport number of 0.6988 were obtained, which is 67% and 72% of polymeric nafion performance, respectively. In addition, the minimal oxygen mass transfer coefficient achieved by this approach was equal to 5.62?×?10?4 cm/s, which is very close to the commercial nafion membrane value. The fabricated PDC composite membranes meet all the essential criteria required for their use in MFC applications and represent a high potential to overcome limitations of polymeric membrane. 相似文献
98.
Mag. Dr. Michaela Poppe DI MSc. Dr. Andreas Zitek DI Sigrid Scheikl DI Sabine Preis Ass.-Prof. DI Dr. Reinfried Mansberger DI Roland Grillmayer ao.Univ.-Prof. DI Dr. Susanne Muhar 《?sterreichische Wasser- und Abfallwirtschaft》2013,65(11-12):429-438
A scientific understanding of the processes at work in river landscapes represents an important basis for including the local populace in effective and sustainable river landscape management. By conveying system-based knowledge to students, these future inhabitants and users of river landscapes will be better able to recognize contexts and connections, understand project-related decisions and policies, and support sustainable planning efforts. As such, in October 2012 the Austrian Federal Ministry for Science and Research started the “FlussAu:WOW!” project, part of the “Sparkling Science” research program. In the project, scientists work together with the students from two upper-level high-school classes over a period of two years, investigating research questions on river landscape management. The scientific goal of the project is to create a set of indicators to represent the functionality of floodplains. In the first school year, the researchers worked on key questions together with the students in workshops, performed field surveys and analyzed the results of fieldwork. In the subsequent discussions, the researchers constantly pointed out the complex interrelations at work in river-floodplain systems. Students’ knowledge was evaluated in pre-project and post-project tests. The analysis of the pre-tests revealed major knowledge gaps on questions concerning river landscape management, e.g. on factors that place major pressures on these regions. A comparison between the pre- and post-tests confirmed a significant improvement in the students’ factual knowledge after the first year; however, the post-project tests only showed a coupling of that knowledge with a recognition of cause-and-effect relations in sporadic cases. Beyond factual knowledge, it is above all a grasp of the interconnections between individual system elements that serves as an essential basis of education. Interactive, modern approaches are critical to conveying interdisciplinary knowledge. As part of the “FlussAu:WOW!” project, in the second school year system-based learning is implemented with the help of innovative modeling and simulation software. In both the pre- and post-tests, questions on the students’ interests revealed a high level of motivation to join in the research, and considerable interest in questions concerning nature and the environment. As a result, by the end of the first school year the cooperation between researchers, educators and students had already made a valuable contribution to sustainable river landscape management. 相似文献
99.
Vera Kmonickova Michaela Frolikova Klaus Steger Katerina Komrskova 《International journal of molecular sciences》2020,21(23)
The LINC (LInker of Nucleoskeleton and Cytoskeleton) complex is localized within the nuclear envelope and consists of SUN (Sad1/UNc84 homology domain-containing) proteins located in the inner nuclear membrane and KASH (Klarsicht/Anc1/Syne1 homology domain-containing) proteins located in the outer nuclear membrane, hence linking nuclear with cytoplasmic structures. While the nucleoplasm-facing side acts as a key player for correct pairing of homolog chromosomes and rapid chromosome movements during meiosis, the cytoplasm-facing side plays a pivotal role for sperm head development and proper acrosome formation during spermiogenesis. A further complex present in spermatozoa is involved in head-to-tail coupling. An intact LINC complex is crucial for the production of fertile sperm, as mutations in genes encoding for complex proteins are known to be associated with male subfertility in both mice and men. The present review provides a comprehensive overview on our current knowledge of LINC complex subtypes present in germ cells and its central role for male reproduction. Future studies on distinct LINC complex components are an absolute requirement to improve the diagnosis of idiopathic male factor infertility and the outcome of assisted reproduction. 相似文献
100.
Vyskoilov Elika Vrbkov Eva Trejbal Ji Vakov Michaela erven Libor 《Catalysis Letters》2022,152(5):1417-1427
Catalysis Letters - Ni/Ru metals supported on cheap and available support montmorillonite K10 were used for the selective hydrogenation of levulinic acid to γ-valerolactone. Different loadings... 相似文献