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21.
Epirubicin (EPI) is one of the potent breast cancer (BC) chemotherapeutic agents, but its adverse effects limit its efficacy. Herein, EPI was selected to be loaded in liposomal carrier, which has been targeted by a monoclonal antibody, Herceptin. The preparation process of liposomes was a modified ethanol injection method followed by Herceptin conjugation. The in vitro cell toxicity and cellular uptake of optimum formulation against HER2+ and HER2− cancer cell lines were evaluated. The results showed that the drug loading (DL%) and encapsulation efficiency (EE%) of liposome preparation method yielded 30.62% ± 0.49% and 62.39% ± 8.75%, respectively. The average size of naked liposomes (EPI‐Lipo) and immunoliposomes (EPI‐Lipo‐mAb) was 234 ± 9.86 and 257.26 ± 6.25 nm, with a relatively monodisperse distribution, which was confirmed by SEM micrographs. The release kinetic followed Higuchi model for both naked and immunoliposomes. In vitro cytotoxicity study on three different BC cell lines including BT‐20, MDA‐MB‐453 and MCF‐7 demonstrated higher toxicity of EPI in the Herceptin conjugated form (EPI‐Lipo‐mAb) in comparison with the free EPI and EPI‐Lipo in HER2 overexpressing cell line. In addition, the cellular uptake study showed a higher uptake of immunoliposomes by MCF‐7 cells in comparison with naked liposomes. In conclusion, these data show that the targeted delivery of EPI to breast cancer cells can be achieved by EPI‐Lipo‐mAb in vitro, and this strategy could be used for breast cancer therapy with further studies.  相似文献   
22.
The microstructure of a trial martensitic chromium steel containing a high content of boron (250 ppm) was characterized in detail in the as-tempered and aged conditions. This steel has a similar composition and heat treatment as the TAF steel that still is unsurpassed in creep strength among all 9 to 12 pct chromium steels. Characterization was performed by using scanning electron microscopy, energy-filtered transmission electron microscopy, secondary ion mass spectroscopy, and atom probe tomography. Focus was placed on investigating different types of precipitates that play a key role in improving the creep resistance of these steels. The low tempering temperature of 963 K (690 °C) is enough for the precipitation of the full volume fraction of both MX and M23C6. A high boron content, more than 1 at. pct, was found in M23C6 precipitates and they grow slowly during aging. The high boron level in the steel results in metal borides rather than BN with the approximate formula (Mo0.66Cr0.34)2(Fe0.75V0.25)B2. Two families of MX precipitates were found, one at lath boundaries about 35 nm in size and one dense inside the laths, only 5 to 15 nm in size.  相似文献   
23.
The changes that occur during the commercial production of budu, a Malaysian fish sauce were examined. It was shown that the maximum volume of liquid was produced after 140 days and that proteolysis continued to occur until 200 days when 56% of the insoluble fish protein had been hydrolysed into soluble form. The colour was produced early during the fermentation. The aroma constituents, ammonia and trimethylamine, were produced early in the fermentation process, but the volatile fatty acids did not appear when fresh fish (Stolephorus) was used for the fermentation. In the commercial production, n-butanoic acid concentration remained constant during the fermentation but ethanoic acid did increase during the period. The salt concentration and the pH were approximately constant throughout, at 26% and 5.65, respectively.  相似文献   
24.
One of the most useful geosynthetics in soil reinforcement is geogrid due to its high tensile strength, having a great influence on soil skeleton reinforcement and eventually, increasing bearing capacity of the foundation. In this research, a series of 36 repeated plate load tests have been carried out to investigate the scale effect on geogrid-reinforced soil, tending to further understanding of the behaviour of geogrid-reinforced soil system. Four different soil grains sizes, two different geogrid's aperture sizes (with roughly the same tensile strength) and three different loading plate sizes are the variables considered. During the tests, the applied loading and soil surface settlements were recorded to evaluate the systems' response. As it was expected, the reinforced soil exhibited higher bearing capacity than the unreinforced status, up to 635%. The results show that increasing loading plate size and soils' particle size fortify the response of foundation, especially in reinforced status, against the loading plate penetration. The results further focused on the important role of scale effect on the response of reinforced foundation. It was understood that the optimum nominal aperture size of geogrids should be about 4 times of medium grain size of soil. Also, it was found out that in order to acquisition of highest reinforcement benefits, the footing's width should be in the range 13–25 (20 in average) times of medium grain size of the backfill. Finally, to achieve the best results, it is recommended that the aperture size of geogrids should be selected roughly 0.2 times of footing width.  相似文献   
25.
This paper provides a simple methodology to analyze the effects of future growth and changes in a metropolitan area on the transportation network of a single city inside the area. In order to present the analysis process, the impact of projected regional employment and population growth on the transportation network of one suburban city in Dallas-Fort Worth metropolitan area is investigated. One of the main features of this approach is the use of the major accesses to the city to divide the rest of metropolitan area into few major zones or origin and destination which allow easier manipulation of data.  相似文献   
26.
27.
A new model for the flexural vibration of an atomic force microscope cantilever is proposed, and a closed-form expression is derived. The effects of angle, damping and tip moment of inertia on the resonant frequency were analysed. Because the tip is not exactly located at one end of the cantilever, the cantilever is modelled as two beams. The results show that the frequency first increases with increase in angle and then decreases to a constant value for high values of the angle. Moreover, the damping is increased at lower contact positions. The tip moment of inertia is also sensitive to the resonant frequency at small values for the odd modes and large values for the even modes.  相似文献   
28.

The existence of different stakeholders in a system, the actual and potential contradictions that may not be identified, and the long-term consequences of each decision are significant challenges in the process of developing a system. Information technology-based services are among the systems that usually interact with users and have a significant impact on their environment. The present study attempts to properly understand and develop the services of an intercity payment system in Iran. After recognizing the problem step by step, an innovative methodology was designed to structure the problem. In the early stages, using one of the critical frameworks after identifying stakeholders, research on the system was conducted, and interviews were identified, which are involved and affected people by the system. Critiques of stakeholders became to viable option during the specified process. Additionally, inspired by the soft operational research (OR), the obtained results were examined in terms of the executive contradictions, and then to evaluate and select the correct options, the long-term consequences of each decision were identified using Multi Attribute Decision-Making. Moreover, the evaluation of options for different stakeholders was done by their representatives using their related criteria to select the best options from the opposing options. Ultimately, the presented methodology is designed to provide a slow movement from qualitative to quantitative form. Consequently, based on creating shared value, the product has been redesigned to satisfy all stakeholders.

  相似文献   
29.
In order to lessen the energy loss of buildings during the operation phase, and also considering the importance of sustainable construction, producing bricks having more desirable thermal characteristics has become essential. In this study, insulation bricks composed of expanded perlite (EP), natural zeolite, ground granulated blast furnace slag (GGBFS) and clay were fabricated. The effect of replacing clay with GGBFS, zeolite and EP in amounts up to 15%, 15%, and 50% respectively on the bricks' properties was investigated. Mix proportion parameters of bricks were analyzed using the Taguchi method. Various properties of bricks including density, weight loss, shrinkage, apparent porosity, water absorption, resistance to freezing and thawing, compressive strength, thermal conductivity, and microstructural analysis of fired bricks were examined and compared against standard requirements for bricks. Overall, the results showed that while satisfying the standard requirements, bricks containing the aforementioned additives had lower thermal conductivity compared to normal bricks, and therefore, they could be utilized as heat insulation materials.  相似文献   
30.
Evolution of Web technologies has made e-learning a popular common way of education and training. As an outcome, learning content adaptation has been the subject of many research projects lately. This paper suggests a framework for building an adaptive Learning Management System (LMS). The proposed architecture is based upon multi-agent systems and uses both Sharable Content Object Reference Model (SCORM) 2004 and semantic Web ontology for learning content storage, sequencing and adaptation. This system has been implemented upon a well known open-source LMS and its functionalities are demonstrated through the simulation of a scenario mimicing the real life conditions. The result reveals the system effectiveness for which it appears that the proposed approach may be very promising.  相似文献   
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