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91.
In the decade of the 1990's the human aspect has once again taken center stage in the design and operation of commercial aircraft. As occupation health and safety has gained importance in society in general, it has gained even more importance in the design an operation of commercial aircraft. In aircraft design today, the man-machine interface is considered in every task of the human workload. The discipline of ergonomics truly impacts each phase of product or tool design. At IPTN, the ergonomics effort is principally being applied to the design of the cockpit, cabin and cargo compartment of the N250. The ergonomists at IPTN are keenly aware that there would be a conflict between the user and his working environment without proper attention to the human considerations in the design is left for ergonomists and innovative programs like IPTN's participatory approach, to ensure that the human aspect is optimized in the man-machine interface. 相似文献
92.
93.
Dongfei Liu Ermei Mäkilä Hongbo Zhang Barbara Herranz Martti Kaasalainen Päivi Kinnari Jarno Salonen Jouni Hirvonen Hélder A. Santos 《Advanced functional materials》2013,23(15):1893-1902
A major bottleneck in nanometer‐scale drug delivery systems is the fabrication of nanocarriers with excellent stability under physiological conditions that can both efficiently encapsulate therapeutic agents and controllably release their payloads. Herein, the formation of a novel nanocomposite based on the encapsulation of thermally hydrocarbonized porous silicon (THCPSi) nanoparticles with solid lipid nanoparticles (SLNs) on a 1:1 ratio is described. The THCPSi‐SL nanocomposites (THCPSi‐SLNCs) are formed using a solid‐in‐oil‐in‐water emulsion solvent evaporation method. TEM and FTIR analyses prove that THCPSi nanoparticles are successfully encapsulated in the SLN matrix. The formation of the THCPSi‐SLNCs alters the surface smoothness and hydrophobicity of the THCPSi nanoparticles, and also remarkably enhances their stability in human plasma. After encapsulation, the cytocompatibility of the THCPSi nanoparticles with intestinal, liver, and macrophage cancer cells is also greatly improved. A prolonged release of the model drug, furosemide, from THCPSi‐SLNC is achieved, indicating that the SLN matrix successfully seals the pores of the THCPSi nanoparticles. Flow cytometry and confocal fluorescence microscopy studies demonstrates the significantly reduced cellular association of THCPSi‐SLNCs with the cells comparing to bare THCPSi nanoparticles. Overall, the THCPSi‐SLNCs exhibits superior suspensibility and better stability against aggregation in aqueous buffer solutions, increases the particle surface smoothness and cytocompatibility, reduces the cellular association, increases the in vitro stability in human plasma, and prolonges the drug release. These results suggest that the nanocomposite is a promising nanovector system for drug delivery applications. 相似文献
94.
The aim of this review was to investigate human exposure to relevant indoor air contaminants, predictors affecting the levels, and the means to reduce the harmful exposure in indoor sports facilities. Our study revealed that the contaminants of primary concern are the following: particulate matter in indoor climbing, golf, and horse riding facilities; carbon dioxide and particulate matter in fitness centers, gymnasiums, and sports halls; Staphylococci on gymnasium surfaces; nitrogen dioxide and carbon monoxide in ice hockey arenas; carbon monoxide, nitrogen oxide(s), and particulate matter in motor sports arenas; and disinfection by-products in indoor chlorinated swimming pools. Means to reduce human exposure to indoor contaminants include the following: adequate mechanical ventilation with filters, suitable cleaning practices, a limited number of occupants in fitness centers and gymnasiums, the use of electric resurfacers instead of the engine powered resurfacers in ice hockey arenas, carefully regulated chlorine and temperature levels in indoor swimming pools, properly ventilated pools, and good personal hygiene. Because of the large number of susceptible people in these facilities, as well as all active people having an increased respiratory rate and airflow velocity, strict air quality requirements in indoor sports facilities should be maintained. 相似文献
95.
Frans Storgårds Päivi Mäki-Arvela Narendra Kumar Janne Peltonen Jarno Salonen Markus Perula Kari Eränen Vincenzo Russo Dmitry Yu. Murzin Henrik Grénman 《Topics in Catalysis》2018,61(18-19):1888-1900
Activity of heterogeneous catalysts for synthesis of Guerbet alcohols from hexanol was evaluated. Commercial synthetic hydrotalcite (HT) was used in the aldol condensation reaction, which is a part of the Guerbet reaction network. HTs were calcined at different temperatures in order to modify their basicity and additionally, NaOH was applied in some experiments as a homogeneous base. The homogeneous base proved to be more efficient in aldol condensation experiments, while HT also performed in an acceptable way. Bi-functional metal containing HTs were synthesized by wet impregnation and co-precipitation methods employing different active metals. The materials were characterized with a number of methods, including CO2-TPD, pyridine-FTIR, nitrogen physisorption, transmission electron microscopy, SEM–EDX and XRD. Copper containing catalysts produced hexyl-hexanoate with a very high selectivity, while Ni-containing counterparts exhibited the highest selectivity towards the Guerbet alcohol. The co-precipitated catalysts were more active in the current study than the ones produced by wet-impregnation. Nevertheless, synthesis of Guerbet alcohols from hexanol with a one-pot method proved to be challenging, with the best yield of the Guerbet product in 24 h being 5%. This is proposed to be largely due to thermodynamic limitations, which was confirmed by calculations of thermodynamics. 相似文献
96.
ABSTRACT Innovation within companies is generated by a combination of different types of knowledge from external and geographically dispersed sources. Although the geographical dimension of collaboration has previously been investigated, studies have not distinguished between different types of knowledge involved in collaboration. This article analyses how the number of collaborations between pharmaceutical multinational companies (MNCs) and external organizations is affected by geographical distance, distinguishing between four knowledge types: basic science, clinical science, core knowledge, and exploration knowledge. We use co-publications as a proxy for collaborations. Our results show that collaborations in basic science and core knowledge areas are more negatively affected by geographical distance than collaborations within clinical science and exploration knowledge areas. This suggests that the importance of geographic proximity depends on the type of knowledge that is being transferred in R&D collaborations. Our results have implications for companies´ collaboration strategies and their choices for the R&D sites´ location. 相似文献
97.
Karpas Z Lorber A Sela H Paz-Tal O Hagag Y Kurttio P Salonen L 《Radiation protection dosimetry》2006,118(1):106-110
The (234)U/(238)U ratio in water, hair and nails samples was determined by multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) and inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) and by alpha-spectrometry for the water samples only. A correlation of 0.99 was found between the two ICPMS methods and of 0.98 with alpha-spectrometry. The range of activity ratios was between 0.9 and 2.6 according to the MC-ICPMS measurements. The reproducibility of both ICPMS techniques was better than 4% for water samples containing 1 mug l(-1) of uranium and a (234)U/(238)U atom ratio of 54.9 x 10(-6). Sample preparation for the ICPMS consisted of dilution of water samples containing >10 microg l(-1) of uranium and measurement time was approximately 1 min, while alpha-spectrometry involved pre-concentration and separation of the uranium and counting times of 1,000 min. 相似文献
98.
Vaahtio M Peltola T Hentunen T Ylänen H Areva S Wolke J Salonen JI 《Journal of materials science. Materials in medicine》2006,17(11):1113-1125
This study looks for grounds to alter the chemical composition (phosphate, calcium, silica and carbonate), dissolution properties,
structure and nanotopography of the biomimetically processed surfaces on bioactive ceramics to optimize their shown ability
to influence bone cell behaviour and production of new bone. In the bone environment desirable characteristic of these materials
is their ability to be remodeled by natural osteoclastic resorption. Different silica and carbonate containing calcium phosphate
layers were prepared on bioactive glasses 9 (S53P4) and 1-98 (S53P2) and sol-gel processed pure silica SiO2 in C- and R-SBF (conventional and revised simulated body fluid) for varying periods of time. It was shown that in R-SBF the
CaP layer formed faster compared to C-SBF. The CaP layer in the R-SBF contained more carbonate (CO3
2−) compared to that formed with the same immersion time in C-SBF. The CaP so formed in R-SBF with faster precipitation is more
amorphous than the bonelike HCA formed in C-SBF. The results indicate that the most suitable surface for both osteoblasts
and osteoclasts was found to be an amorphous CaP having mesoporous nanotopography and proper dissolution rate of calcium and
silica. 相似文献
99.
This paper presents a novel parallel memory architecture for multimedia computers. Applying a configurable or programmable addressing circuitry capable of parallel memory accesses, the memory management of multimedia applications can be enhanced. Necessary computer architecture changes to virtual address representation, paging, virtual memory, address computation circuitry and data permutation are discussed. These changes allow the memory to be partitioned for different access functions. In addition, the same memory area can be accessed by multiple access patterns. Therefore, a general-purpose computing system that is capable of exploiting the repeating memory access patterns in its applications can be built. Performance of the configurable parallel memory architecture (CPMA) is analyzed in the case of a selection of algorithms from a video encoder. These motion estimation algorithms and zigzag scanning benefit from the multiple memory access functions, which is apparent from the comparisons to the traditional sequential memory accesses. 相似文献
100.
E-M. Salonen 《International journal for numerical methods in engineering》1979,14(11):1653-1663
The concept of fictitious external loading being in exact equilibrium with the internal stresses in a structure is introduced. It is employed in conjunction with the principle of virtual work in an effort to examine certain details of the finite element displacement method in an alternative way. 相似文献