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101.
Woo A.C. Wang H.T.G. Schuh M.J. Sanders M.L. 《Antennas and Propagation Magazine, IEEE》1993,35(1):84-89
Low- and high-frequency measurements are presented of five differently shaped targets: the NASA almond, ogive, double ogive, cone-sphere, and cone-sphere with gap. These were measured from 700 MHz to 16 GHz. The metallic targets are made of aluminum, and were cut by a numerically controlled mill to maintain the surface precision. Except for the almond target, all the targets were made in two parts and joined by sleeves and screws. The measurements are computational electromagnetics (CEM) validation measurements for the Electromagnetic Code Consortium (EMCC) 相似文献
102.
Günther Schuh Wolfgang Schultze Michael Schiffer Annette Rieger Stefan Rudolf Heiko Lehbrink 《Production Engineering》2014,8(3):383-395
Modular product architectures are used by many firms today to achieve a high degree of product differentiation whilst reducing cost through economies of scale. At the same time, the firms are increasing architecture lifetimes to 10 years or more, which brings up new challenges for the development process. Uncertainties regarding future product features need to be anticipated when designing the architecture to minimize modification efforts. Nevertheless, existing approaches for designing modular product architectures are mainly based on static requirements and thereby neglect the dynamics of the market that influence future product features. This paper aims at presenting a method utilizing scenario-planning and simulations in the product range planning process to determine future product features and their uncertainties as a basis for the product architecture design. Possible feature specifications are derived from product environment scenarios and linked to the factors influencing the scenarios, to calculate their expected values and deviations. 相似文献
103.
M.H. Ghaffari H. Sadri K. Schuh G. Dusel Dörte Frieten C. Koch C. Prehn J. Adamski H. Sauerwein 《Journal of dairy science》2019,102(7):6571-6586
Biogenic amines (BA) are a class of nitrogenous compounds that are involved in a wide variety of physiological processes, but their role in transition cows is poorly understood. Our objectives were to describe the longitudinal changes of BA in serum and in skeletal muscle during the transition period and to characterize temporal responses of BA in relation to body condition score (BCS) of periparturient dairy cows. Fifteen weeks before calving, 36 multiparous Holstein cows were assigned to 2 groups (n = 18 per group) that were fed differently to reach either high [HBCS; net energy for lactation (NEL) = 7.2 MJ/kg of dry matter (DM)] or normal BCS (NBCS; NEL = 6.8 MJ/kg of DM) at dry-off. The targeted BCS and back fat thickness (BFT) at dry-off (HBCS, >3.75 and >1.4 cm; NBCS, <3.5 and <1.2 cm) were reached. Thereafter, both groups were fed identical diets. Blood samples and muscle (semitendinosus) biopsies were collected at d ?49, +3, +21, and +84 relative to parturition. In serum and skeletal muscle, BA concentrations were measured using a targeted metabolomics assay. The data were analyzed as a repeated measure using the MIXED procedure of SAS. The serum concentrations of most BA (i.e., creatinine, taurine, carnosine putrescine, spermine, α-aminoadipic acid, acetylornithine, kynurenine, serotonin, hydroxyproline, asymmetric dimethylarginine, and symmetric dimethylarginine) fluctuated during the transition period, while others (i.e., spermidine, phenylethylamine) did not change with time. The muscle concentrations of BA remained unchanged over time. Creatinine had the highest concentrations in the serum, while carnosine had the highest concentration among the muscle BA. The serum concentrations of creatinine (d +21), putrescine (d +84), α-aminoadipic acid (d +3), and hydroxyproline (d +21) were or tended to be higher for HBCS compared with NBCS postpartum. The serum concentrations of symmetric dimethylarginine (d ?49) and acetylornithine (d +84) were or tended to be lower for HBCS compared with NBCS, respectively. The serum kynurenine/tryptophan ratio was greater with HBCS than with NBCS (d +84). Compared with NBCS, HBCS was associated with lower muscle concentrations of carnosine, but those of hydroxyproline were higher (d ?49). In both serum and muscle, the asymmetric dimethylarginine concentrations were greater with HBCS than with NBCS (d ?49). No correlation was found between serum and skeletal muscle BA. This study indicates that overconditioning of dairy cows may influence serum and muscle BA concentrations in the periparturient period. 相似文献
104.
105.
G��nther Schuh Jens Arnoscht Arne Bohl Daniel Kupke Christopher Nu?baum Jerome Quick Michael Vorspel-R��ter 《Production Engineering》2011,5(4):341-350
Companies in high wage countries are increasingly confronted with the challenge of optimizing economies of scope and economies
of scale simultaneously to succeed on a global market place. An integrated assessment of production systems facing this challenge
is essential to evaluate the actual state of a company and to provide a basis for drawing the right conclusions to reconfigure
production systems successfully. In this paper an integrated model for measuring economies of scope as well as economies of
scale is introduced, defining the fundamental domains of a production system. The major objectives resulting from the overall
scale-scope dilemma are broken down for each domain and the main dimensions for an assessment of each domain are defined.
A new measure named Degree of Efficiency is defined, quantifying the fulfillment of the opposing objectives in each domain
and hence, the contribution to an overall resolution of the scale-scope dilemma. 相似文献
106.
Enhanced Molecular Alignment in Poly‐l‐Lactic Acid Nanotubes Induced via Melt‐Press Template‐Wetting
Molecular ordering in polymers can have a drastic effect on their properties and can be used to induce or enhance functionality. In the case of poly‐l ‐lactic acid (PLLA), which is a widely used polymer in biomedicine, sensors, and actuators, preferential orientation of chains can lead to significantly enhanced electromechanical properties. In this context, template‐wetting is a straightforward method of producing polymer nanostructures, which can lead to some degree of molecular order in the polymer. Template‐wetting of PLLA has not been fully explored, especially in terms of morphological and/or structural characterization. In this work, PLLA nanotubes are grown via a modification of the template‐wetting process, referred to here as melt‐press template‐wetting. The nanotubes are thoroughly characterized with wide‐angle X‐ray diffraction, isothermal differential scanning calorimetry, and polarized light optical microscopy. This characterization indicates that the polymer chains in these PLLA nanotubes are aligned parallel to the cylindrical axis of the nanotube, which may be beneficial in certain applications. 相似文献
107.
A. Schuh 《Atomic Data and Nuclear Data Tables》2010,96(6):817-823
Twenty-eight iron isotopes have been observed so far and the discovery of these isotopes is discussed here. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented. 相似文献
108.
Production of Sterols from Residues of Fat-Splitting Sterols are enriched in distillation residues of fat-splitting and fat-transesterification (with methanol); they are biotechnologically interesting starting materials. Possibilities for further concentrating the sterols are described. 相似文献
109.
U. Stille K. Zoller H. Herrmann A. Naumann H. Schuh W. Linke C. Keller U. Neubert Paul E. Klein R. Jung W. Rädeker H. W. Hahnemann Th. Gaymann 《Forschung im Ingenieurwesen》1959,25(1):33-36
Ohne Zusammenfassung
VDI 相似文献
110.
Increase of Internet traffic and introduction of triple-play services force operators to increase network capacity at moderate costs. Introduction of higher electronic time-division multiplexing (ETDM) channel bit rate targets reduce the cost per bit for the transmission due to lower power consumption, smaller footprint, less management effort, and complexity of the systems. Improved performance of electronic and optoelectronic components allows for research on ETDM bit rates beyond 40 Gb/s, which is currently the highest standardized channel bit rate for optical telecommunication networks. In this paper, an overview of recent progress in high-speed ETDM technology for 80 Gb/s and beyond and results of high-speed ETDM transmission experiments are given. Currently, the speed of electronics enables ETDM systems with line rates of 80/85 Gb/s and even 100 Gb/s, which is expected to be the next generation of Ethernet in data communication 相似文献