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91.
Bioactive peptides from Ixora coccinea Linn flowers have been reported to have anticancer activity against various cancer cells. Zinc oxide nanoparticle is the promising metal nanoparticle for anticancer applications. In the present work, ZnO was synthesized using I. coccinea Linn flower extract. The synthesized ZnO nanoparticle was found as phytonanocomposite of ZnO nanoparticle and bioactive components. The synthesized ZnO phytonanocomposite was confirmed using UV Spectroscopic analysis with maximum wavelength at 357.6 nm. The presence of bioactive peptides in the nanophytocomposite was confirmed using FT-IR analysis with strong peaks at 3402 and 1629 cm?1. The particle size and surface characteristics of bioactive phytonanocomposite of ZnO was studied using Scanning Electron Microscope. The anticancer activity of zinc oxide nanocomposite of I. coccinea Linn flower extract was found to be efficient on MCF-7 cell line.  相似文献   
92.
Solvent‐free cyanoethylation of selected alcohols with acrylonitrile (AN) using a weakly basic polymer resin, Amberlyst A‐21 (AA‐21) was studied at 75°C. The conversion of primary alcohols, 1‐octadecanol, hexane‐1,6‐diol, pentaerythritol, but‐2‐yne‐1,4‐diol, N‐methyldiethanolamine, triethanolamine and diethanolamine is higher than secondary alcohols, isopropanol and glycerol in the presence of polymer resin. Of various alcohols, but‐2‐yne‐1,4‐diol gave the product in high conversion (87%) in cyanoethylation with a polymer resin/AN weight ratio of 0.04. The polymer resin showed recycling ability only in two cycles to produce cyanoethylated product from diethanolamine. In case of 1‐octadecanol, hexane‐1,6‐diol, and N‐methyldiethanolamine with AN under similar conditions, no recycling ability was observed. Thermally treated polymer resin at 75°C afforded the product in lower conversion (55%) whereas the same product was obtained in 69% when fresh polymer resin was used in cyanoethylation of 1‐octadecanol. No catalytic effect was observed for polymer resin treated at 100°C. Fourier transform infrared (FTIR) spectra showed CN stretching at 2248 cm?1 for the polymer resin collected after the reaction which was caused by the AN binding on polymer resin during the reaction. As per thermogravimetric curves, 5% weight loss was observed at 201°C for recovered resin and at 161°C for polymer resin treated at 100°C. Scanning electron microscope images confirmed the AN binding on polymer beads after catalytic activity. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
93.
In this paper an interval type-2 fuzzy logic controller (IT2FLC) was proposed for thyristor controlled series capacitor (TCSC) to improve power system damping. For controller design, memberships of system variables were represented using interval type-2 fuzzy sets. The three-dimensional membership function of type-2 fuzzy sets provided additional degree of freedom that made it possible to directly model and handle uncertainties. Simulations conducted on a single machine infinite bus (SMIB) power system showed that the proposed controller was more effective than particle swarm optimization (PSO) tuned and type-1 fuzzy logic (T1FL) based damping controllers. Robust performance of the proposed controller was also validated at different operating conditions, various disturbances and parameter variation of the transmission line parameters.  相似文献   
94.
The present study introduces the properties of three thermo-responsive shape memory polymer nanocomposites (SMPCs), viz. SMPC–NiO (SMP with nickel oxide), SMPC-Fe2O3 (SMP with iron oxide), and SMPC-Fe2NiO4 (SMP with iron nickel oxide) along with the neat SMP blend. Styrene-Butadiene rubber and poly ε-caprolactone (PCL) polymer are the vital part, which forms the backbone of polymer-elastomer blend matrix. This study helps to understand the effect and influence of these metal oxide nanofillers' integrated blend on their different inbuilt properties. The tensile test and dynamic mechanical analysis studies confirmed that SMPC-Fe2NiO4 holds a large elastic modulus value and very rigid compared to other SMPCs. Thermal decomposition studies using differential scanning calorimetry, thermogravimetric (TG) analysis, and TG-gas chromatography and mass spectrometry results show that the nanocomposites undergoes a two-stage decomposition process. The shape memory test reveals that the time taken for temporary shape recovery is high for SMPC-Fe2NiO4 because of its rigid nature and low for SMPC-Fe2O3. The results revealed that, from this exploratory study, the integration of metal oxide nanopowder fillers, especially Fe2O3 with neat SMP, showed better properties.  相似文献   
95.
The low cycle fatigue behaviour of precipitation strengthened nickel-base superalloy 720Li containing a low concentration of interstitial carbon and boron was studied at 25, 400 and 650 °C. Cyclic stress response at all temperatures was stable under fully reversed constant total strain amplitude (Δε/2) when Δε/2 ? 0.6%. At Δε/2 > 0.6%, cyclic hardening was followed by softening, until fracture at 25 and 650 °C. At 400 °C, however, cyclic stress plateaued after initial hardening. Dislocation–dislocation interactions and precipitate shearing were the micromechanisms responsible for the cyclic hardening and softening, respectively. The number of reversals to failure vs. plastic strain amplitude plot exhibits a bilinear Coffin–Manson relation. Transmission electron microscopy substructures revealed that planar slip was the major deformation mode under the conditions examined. However, differences in its distribution were observed to be the cause for the bilinearity in fatigue lives. The presence of fine deformation twins at low Δε/2 at 650 °C suggests the role of twinning in homogenization of cyclic deformation.  相似文献   
96.
Deubiquitinases are important components of the protein regulatory network and, hence, constitute a tempting drug target. We report herein structure–activity relationship studies to develop halogen-substituted isoquionoline-1,3-dione-based inhibitors of the deubiquitinase USP2. In contrast to our previous reports, the best compound discovered was found to act through a reactive oxygen species independent, uncompetitive mechanism with an IC50 of 250 nm . We show the crucial role of halogens in the common scaffold to provide potency and selectivity of our compound, where the introduction of the fluorine atom completely switches the selectivity of the inhibitor between USP2 and USP7. Our cellular studies highlight the potential applicability of the reported compound for in vivo experiments. The discovery of the isoquinoline-1,3-dione core and the knowledge obtained with regard to halogen substituents provide a platform towards understanding USP2 inhibition and the development of highly selective next-generation deubiquitinase inhibitors.  相似文献   
97.
Cloud computing is the highly demanded technology nowadays. Due to the service oriented architecture, seamless accessibility and other advantages of this advent technology, many transaction rich applications are making use of it. At the same time, it is vulnerable to hacks and threats. Hence securing this environment is of at most important and many research works are being reported focusing on it. This paper proposes a safe storage mechanism using Elliptic curve cryptography (ECC) for the Transaction Rich Applications (TRA). With ECC based security scheme, the security level of the protected system will be increased and it is more suitable to secure the delivered data in the portable devices. The proposed scheme shields the aligning of different kind of data elements to each provider using an ECC algorithm. Analysis, comparison and simulation prove that the proposed system is more effective and secure for the Transaction rich applications in Cloud.  相似文献   
98.
This paper presents methodologies for crack growth study and fatigue remaining life prediction of reinforced concrete structural components accounting for the corrosion effects. Stress intensity factor (SIF) has been computed by using the principle of superposition. At each incremental crack length, net SIF has been computed as the difference of SIF of plain concrete and reinforcement. The behaviour of reinforcement has been considered as elasto-plastic. Uniform corrosion rate has been assumed in the modeling. Corrosion effect has been accounted in the form of reduction in the diameter and modulus of elasticity of steel. Numerical studies have been carried out to validate the methodologies. It is observed that the predicted remaining life for RC beam without corrosion effects is significantly larger compared to plain beams. The predicted remaining life decreases with increase in percentage of corrosion.  相似文献   
99.
In many network management applications, likepost-mortem fault analysis or performance trendsprofiling, it is advantageous to have the ability toview the state of the network as it was at some time in the past. To support such Temporal Views anefficient data organization, or access method, is neededfor storing and updating network related data (as thenetwork evolves over time) and for retrieving requested past network states. For applications where thenetwork manager is not interested in the full (and maybetoo large) snapshot of a past network state it is usefulif partial state snapshots can be extracted quickly. It is thus of particular interest toconstruct an access method that can efficiently supportPartial Temporal Views. Efficiency implies that arequested partial temporal view should be constructed directly, without first computing the elaboratefull temporal view. In this paper we present a newaccess method (called the Neighbor History Index) forthis problem. One of the advantages of this method is that the update processing is independent ofthe evolution size (the total number of changes in theevolution). In addition, our method uses a small diskspace overhead. We then present a general framework for organizing time-evolving network data. Ourframework distinguishes between flat and hierarchicalevolutions and subsequently between flat andhierarchical temporal views. We also provide a way toefficiently construct temporal views on hierarchicalevolutions. This paper shows that supporting temporalviews on flat or hierarchical evolutions is notexpensive: our solutions use small space overhead, havesmall updating and compute temporal viewsfast.  相似文献   
100.
By the year 2050, the world’s population is predicted to have grown to around 9–10 billion people. The food demand in many countries continues to increase with population growth. Various abiotic stresses such as temperature, soil salinity and moisture all have an impact on plant growth and development at all levels of plant growth, including the overall plant, tissue cell, and even sub-cellular level. These abiotic stresses directly harm plants by causing protein denaturation and aggregation as well as increased fluidity of membrane lipids. In addition to direct effects, indirect damage also includes protein synthesis inhibition, protein breakdown, and membranous loss in chloroplasts and mitochondria. Abiotic stress during the reproductive stage results in flower drop, pollen sterility, pollen tube deformation, ovule abortion, and reduced yield. Plant nutrition is one of the most effective ways of reducing abiotic stress in agricultural crops. In this paper, we have discussed the effectiveness of different nutrients for alleviating abiotic stress. The roles of primary nutrients (nitrogen, phosphorous and potassium), secondary nutrients (calcium, magnesium and sulphur), micronutrients (zinc, boron, iron and copper), and beneficial nutrients (cobalt, selenium and silicon) in alleviating abiotic stress in crop plants are discussed.  相似文献   
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