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31.
Targeting live cell organelles is essential for imaging, understanding, and controlling specific biochemical processes. Typically, fluorescent probes with distinct structural scaffolds are used to target specific cell organelles. Here, we have designed a modular one-step synthetic strategy using a common reaction intermediate to develop new lysosomal, mitochondrial, and nucleus-targeting pH-activable fluorescent probes that are all based on a single boron dipyrromethane scaffold. The divergent cell organelle targeting was achieved by synthesizing probes with specific functional group changes to the central scaffold resulting in differential fluorescence and pKa. Specifically, we show that the functional group transformation of the same scaffold influences cellular localization and specificity of pH-activable fluorescent probes in live primary microglial cells with pKa values ranging from ∼3.2–6.0. We introduce a structure-organelle-relationship (SOR) framework to target nuclei ( NucShine ), lysosomes ( LysoShine ), and mitochondria ( MitoShine ) in live microglia. This work will result in future applications of SOR beyond imaging to target and control organelle-specific biochemical processes in disease-specific models.  相似文献   
32.
The reliable correlation between personality and brain signal ensures that inferences from cognitive processes can be achieved. This research aims primarily to predict one's personality using brain signals. On grounds of Psychology, the inference of personality in this work is performed on the basis of the Myers–Briggs Type Indicator (MBTI) personality inventory. Personality consists of different types of thinking, feeling and behavior patterns. EEG signals are produced when a person is exposed to situations or scenarios via visual information and experiences various emotions or sentiments. In this study, by evaluating brain waves while a person watches personality traits elicitation materials, the identification of the personality traits of an individual is done. The elicitation materials used for the collection of the dataset comprise approximately 50 videos with the pre-defined personality of the dramatic personae and therefore, it is considered to be the ground truth for the experimental procedure of this work. For creating a dataset, sixty participants contributed and gave brain signals. The GP model with the proposed BSH crossover, known as the BSHGP model, is implemented. The maximum performance of the BSHGP model for a 10-fold partition scheme is 84.34%.  相似文献   
33.
Pure ZrB2 powder was Flash sintered in an SPS furnace (FSPS). The samples were densified up to 95.0% in 35 s under an applied pressure of 16 MPa. Compared to Conventional SPS (CSPS), the newly developed FSPS technique resulted in an unprecedented energy and time savings of about 95% and 98% respectively. ZrB2 monoliths obtained by CSPS and FSPS were compared with respect to microstructures, densification behavior, and grain growth. The developed methodology might find application to a wide range of highly conductive ceramics as such refractory borides and carbides.  相似文献   
34.
Liquid exfoliation of graphene generally results in flakes with lateral size of one micron or less on average, too small for many applications. In this paper we describe a method to separate an existing dispersion with mean flake length of ~1 μm into fractions, each with different mean flake size. The initial dispersion is centrifuged at a high centrifugation rate, separating small flakes in the supernatant from large flakes in the sediment. Redispersion of the sediment, followed by successive centrifugation, separation and redispersion cycles can be used to separate the flakes by size so long as the centrifugation rate is decreased with each cycle. This procedure results in a range of dispersions with mean flake length varying from 1 μm for the highest final centrifugation rate to 3.5 μm for the sample whose final centrifugation rate was 500 rpm.  相似文献   
35.
A low‐permittivity dielectric ceramic Li2GeO3 was prepared by the solid‐state reaction route. Single‐phase Li2GeO3 crystallized in an orthorhombic structure. Dense ceramics with high relative density and homogeneous microstructure were obtained as sintered at 1000‐1100°C. The optimum microwave dielectric properties were achieved in the sample sintered at 1080°C with a high relative density ~ 96%, a relative permittivity εr ~ 6.36, a quality factor Q × f ~ 29 000 GHz (at 14.5 GHz), and a temperature coefficient of resonance frequency τf ~ ?72 ppm/°C. The sintering temperature of Li2GeO3 was successfully lowered via the appropriate addition of B2O3. Only 2 wt.% B2O3 addition contributed to a 21.2% decrease in sintering temperature to 850°C without deteriorating the dielectric properties. The temperature dependence of the resonance frequency was successfully suppressed by the addition of TiO2 to form Li2TiO3 with a positive τf value. These results demonstrate potential applications of Li2GeO3 in low‐temperature cofiring ceramics technology.  相似文献   
36.
Two Ag-containing microwave dielectric ceramics AgCa2B2V3O12 (B?=?Mg, Zn) with garnet structure were prepared through solid-state reaction method. Dense ceramics were obtained at low sintering temperatures, 665?°C for AgCa2Zn2V3O12 and 730?°C for AgCa2Mg2V3O12. Their microwave dielectric properties were characterized for the first time and analyzed by means of packing fraction, bond valence, octahedral distortion, Raman spectra and infrared reflectivity spectra. Both compounds displayed high chemical compatibility with Ag electrodes. Additionally, thermally stable ceramics with near-zero temperature coefficients of resonance frequency (τf) were achieved by forming ceramic composites with CaTiO3.  相似文献   
37.
Smart heating devices with reliable self‐regulating performances and high efficiency, combined with additional properties like mechanical flexibility, are of particular interest in healthcare, soft robotics, and smart buildings. Unfortunately, the development of smart heaters necessitates managing normally conflicting requirements such as good self‐regulating capabilities and efficient Joule heating performances. Here, a simple and universal materials design strategy based on a series connection of different conductive polymer composites (CPC) is shown to provide unique control over the pyroresistive properties. Hooke's and Kirchhoff's laws of electrical circuits can simply predict the overall pyroresistive behavior of devices connected in series and/or parallel configurations, hence providing design guidelines. An efficient and mechanically flexible Joule heating device is hence designed and created. The heater is characterized by a zero temperature coefficient of resistance below the self‐regulating temperature, immediately followed by a large and sharp positive temperature coefficient (PTC) behavior with a PTC intensity of around 106. Flexibility and toughness is provided by the selected elastomeric thermoplastic polyurethane (TPU) matrix as well as the device design. The universality of the approach is demonstrated by using different polymer matrices and conductive fillers for which repeatable results are consistently obtained.  相似文献   
38.
Blends were prepared with different levels of chickpea flour (CF) and durum semolina (0–60 %) and were utilized for understanding their influence on product quality. Proximate analysis and rheological characterization of blends were carried out. Noodles were developed and subjected to different physico-chemical, nutritional, cooking quality and sensory analysis, scanning electron microscopy (SEM). Optimized noodles on the basis of its sensory and cooking quality characteristics were improved with different hydrocolloids. Rheological studies revealed that with the increase in the CF content, Farinograph water absorption and dough stability decreased; simultaneously increase in dough development time. Maximum over pressure and curve configuration decreased with increase in CF. Based on the sensory and cooking loss of noodles 50 % formulation was improved with hydrocolloids. Noodles cooking loss reduced to 5.9 % with the addition of guar gum. Sensory scores for the noodles were above 8 in 15 cm scale. Colour value showed an increase in ‘b’ value, indicating increase in yellowness of samples. Texture of noodles became firm with the addition of CF. IVSD (In vitro starch digestibility) reduced from 71 to 29 %. There was a network like formation due to hydrocolloids was observed in SEM, which is the reason for slow release of glucose. Thus, can be used as substitution in noodles and can be included in the diet of malnutritious and diabetic population.  相似文献   
39.
Wireless Personal Communications - Active fingerprinting is an effective penetration testing technique to know about vulnerability of hosts against security threats and network as a whole....  相似文献   
40.
The across-track illumination variation in Earth Observing-1 (EO-1) Hyperion images is a result of wavelength-shift and full-width-at-half-maximum (FWHM)-shift in the cross-track direction. Correction in across-track illumination variation is necessary for accurate spectral matching and classification. This contribution reviews the available methods for the correction of across-track illumination variation, and evaluates them for correcting a Hyperion image of study area around the Udaipur city in western India. We also describe and demonstrated a new technique for correcting these artefacts. For each band, the spatial trends of (a) nonlinear shifts in the nominal centre wavelengths of bands across the image columns and (b) nonlinear changes in the nominal FWHM of bands across the image columns are modelled using quadratic regression and are compensated using a radiance correction factor estimated from the columns characterized by minimum illumination variations in a spectrally flat area of the image. A series of statistical measures, spectral matching, minimum noise fraction transform (MNF) images, and post-correction classification results were used to evaluate the performance of the proposed algorithm vis-à-vis some of the previous methods on the Hyperion image of the study area. The results indicate that the proposed method effectively corrects the across-track illumination effects in the Hyperion image of the study area, and also show better performance in lithological as well as for land-use and land-cover mapping, as compared to the other previous methods.  相似文献   
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