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31.
Direct inhibition of tumor necrosis factor-alpha (TNF-α) action is considered a promising way to prevent or treat TNF-α-associated diseases. The trimeric form of TNF-α binds to its receptor (TNFR) and activates the downstream signaling pathway. The interaction of TNF-α with molecular-grade dimethyl sulfoxide (DMSO) in an equal volumetric ratio renders TNF-α inert, in this state, TNF-α fails to activate TNFR. Here, we aimed to examine the inhibition of TNF-α function by various concentrations of DMSO. Its higher concentration led to stronger attenuation of TNF-α-induced cytokine secretion by fibroblasts, and of their death. We found that this inhibition was mediated by a perturbation in the formation of the functional TNF-α trimer. Molecular dynamics simulations revealed a transient interaction between DMSO molecules and the central hydrophobic cavity of the TNF-α homodimer, indicating that a brief interaction of DMSO with the TNF-α homodimer may disrupt the formation of the functional homotrimer. We also found that the sensitizing effect of actinomycin D on TNF-α-induced cell death depends upon the timing of these treatments and on the cell type. This study will help to select an appropriate concentration of DMSO as a working solvent for the screening of water-insoluble TNF-α inhibitors.  相似文献   
32.
SrFe12O19/Zn0.65Ni0.25Cu0.1Fe2O4 core–shell nanocomposite has been successfully synthesized by sol–gel autocombustion (for SrFe12O19, core) and hydrothermal methods (for Zn0.65Ni0.25Cu0.1Fe2O4, shell). The products were characterized by X-ray powder diffractometer, transmission electron microscopy, fourier transform infrared spectrsocopy, vibrating sample magnetometer, Ultraviolet–visible specroscopy and inductively coupled plasma. Both X-ray powder diffraction, transmission electron microscopy results showed that Zn0.65Ni0.25Cu0.1Fe2O4 shell is on the surface of the SrFe12O19 core. The variations between the magnetic properties of the precursors and nanocomposite may be explained by interphase interactions at the surface of two ferrites. The properties of the SrFe12O19/Zn0.65Ni0.25Cu0.1Fe2O4 core–shell nanocomposite were favourable in its separation, recycling and reuse after reaction. The catalytic activity of SrFe12O19/Zn0.65Ni0.25Cu0.1Fe2O4 core–shell nanocomposite in the presence of NaBH4 were tested against methyl violet.  相似文献   
33.
Silver nanoparticles (Ag(0) NPs) were synthesized by the chemical reduction method, in which ceftriaxone (antibiotic) used as reducing (to convert Ag+ to Ag(0)) and capping agent. UV–Visible spectroscopy revealed the first indication of formation of Ag(0) NPs. FT-IR spectroscopy showed the interaction of formation of bonding between antibiotic standard and silver. X-ray powder diffraction powder pattern confirmed the crystalline nature of prepared Ag(0) NPs. These Ag(0) NPs were used as catalyst for three organic hazardous chemicals i.e., 4-nitro-1,3-Phenylene diamine, 6-methyl-2-nitroanilline, 4-methyle-2-nitroanilline. The prepared Ag(0) NPs showed good catalytic activity against these compounds.  相似文献   
34.
We synthesized mefenamic acid (MA) derived gold nanoparticles (MA-AuNps) in aqueous solution (MA-Au sol). Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) of the sol at 1, 5, 15 and 60 min showed changes in size and shape of formed AuNps. Fourier Transform Infrared (FTIR) Spectroscopy revealed the interaction between AuNps and MA. Each Au sol exhibited exceptional catalytic activity for the reduction of Methylene Blue (MB), Rose Bengal (RB) and Eosin B (EB) dye individually as well as collectively. However, complete reduction of dye(s) was accomplished by Au sol of 5 min in just 15s. The catalytic performance of Ma-Au sol was far superior to that adsorbed on glass. AuNps were recovered with the help of water insoluble room temperature ionic liquid and reused with enhanced catalytic potential. This finding is a novel, rapid and highly economical alternative for environmental safety against pollution by dyes and extendable for control of other reducible contaminants as well.  相似文献   
35.
Scene modeling is the starting point and thus the most crucial stage for many vision-based systems involving tracking or recognition. Most of the existing approaches attempt at solving this problem by making some simplifying assumptions such as that of a stationary background. However, this might not always be the case, as swaying trees or ripples in the water often violate these assumptions. In this paper, we present a novel method for modeling background of a dynamic scene, i.e., scenes that contain “non-stationary” background motions, such as periodic motions (e.g., pendulums or escalators) or dynamic textures (e.g., water fountain in the background, swaying trees, or water ripples, etc.). The paper proposes single-class support vector machine (SVM), and we show why it is preferable to other scene modeling techniques currently in use for this particular problem. Using a rectangular region around a pixel, spatial and appearance-based features are extracted from limited amount of training data, used for learning the SVMs. These features are unique, easy to compute and immune to rotation, and changes in scale and illumination. We experiment on a diverse set of dynamic scenes and present both qualitative and quantitative results, indicating the practicality and the effectiveness of the proposed method.  相似文献   
36.
A novel ultrasound-assisted chitosan–surfactant nanostructure assembly was developed to allow better delivery of chitosan particles into intact fruit tissues for extension of postharvest life. Three solutions of 1 % chitosan–surfactant nanostructure assembly with micelle sizes of 400, 600 and 800 nm were prepared and applied as an edible coating on tomatoes. The fruits were stored at 15?±?2 °C and 70–80 % relative humidity for 20 days. The indicators of tomato ripening, which included loss of firmness, decline of titratable acidity, decline of chlorophyll content and increase in soluble solid content, were delayed in the treated fruits in comparison to the control (p?<?0.05). A delay of approximately 5 days in ripening was observed by evaluating the colour evolution from green to red. The treatment significantly (p?<?0.05) enhanced the phenolic content while maintaining a lower level of respiration in comparison to the control, throughout most of the storage duration. However, weight loss was higher in the treated fruits in comparison to the control. No significant difference in the resultant effects was observed by using chitosan–surfactant nanostructure assemblies of different micelle sizes (p?>?0.05).  相似文献   
37.
One of the leading causes of mortality worldwide is liver cancer. The earlier the detection of hepatic tumors, the lower the mortality rate. This paper introduces a computer-aided diagnosis system to extract hepatic tumors from computed tomography scans and classify them into malignant or benign tumors. Segmenting hepatic tumors from computed tomography scans is considered a challenging task due to the fuzziness in the liver pixel range, intensity values overlap between the liver and neighboring organs, high noise from computed tomography scanner, and large variance in tumors shapes. The proposed method consists of three main stages; liver segmentation using Fast Generalized Fuzzy C-Means, tumor segmentation using dynamic thresholding, and the tumor's classification into malignant/benign using support vector machines classifier. The performance of the proposed system was evaluated using three liver benchmark datasets, which are MICCAI-Sliver07, LiTS17, and 3Dircadb. The proposed computer adided diagnosis system achieved an average accuracy of 96.75%, sensetivity of 96.38%, specificity of 95.20% and Dice similarity coefficient of 95.13%.  相似文献   
38.
This research article is based on the biodiesel synthesis from the marine green macroalga Ulva fasciata, collected from the coast of Karachi, Pakistan using new and the most potential waste catalysts from Pakistan Steel Industry.The oil was extracted with n-hexane then it was analyzed by GC, TLC and by the examination of fuel properties.The metal analysis of catalysts was carried out by chemical tests and flame atomic absorption spectroscopy(FAAS). The thermal treatment of catalysts at 1500–1700 °C during various processes in steel manufacturing industry converted the metals to metal oxides. The presence of CaO, MgO and ZnO in these catalysts made them highly reactive for biodiesel synthesis. The basicity of waste industrial catalysts was calculated to know their basic strength. The transesterification of U. fasciata oil was performed by fast stirring using 9:1 molar ratio of methanol/oil in the presence of seven different waste industrial catalysts for 6 h at 80–100 °C. The solid catalysts were easily separated from product for re-use. In addition, the rate of reaction in the presence of these catalysts was found to be quite feasible. The waste brown dust from the steel converter gave the highest yield(88%) of biodiesel. The production of biodiesel was confirmed by TLC examination and fuel properties in comparison with the ASTM standards.  相似文献   
39.
Neighbourhood environment (NE) is important for physical activity (PA); however, no studies have compared the NE and PA in gated neighbourhoods, especially in developing countries. Therefore, the objective of this study is to compare NE and PA between gated and non-gated neighbourhoods. Objective and subjective (n = 1042) methods and independent sample t-tests were used. Results show that all the indicators are significantly different except housing density. Vigorous Physical Activity (VPA) is higher in gated but walking is higher in non-gated neighbourhoods. Therefore, it can be concluded that gating can reduce walking habits of people living in gated neighbourhoods in developing countries.  相似文献   
40.
The basic goal of scene understanding is to organize the video into sets of events and to find the associated temporal dependencies. Such systems aim to automatically interpret activities in the scene, as well as detect unusual events that could be of particular interest, such as traffic violations and unauthorized entry. The objective of this work, therefore, is to learn behaviors of multi-agent actions and interactions in a semi-supervised manner. Using tracked object trajectories, we organize similar motion trajectories into clusters using the spectral clustering technique. This set of clusters depicts the different paths/routes, i.e., the distinct events taking place at various locations in the scene. A temporal mining algorithm is used to mine interval-based frequent temporal patterns occurring in the scene. A temporal pattern indicates a set of events that are linked based on their relationship with other events in the set, and we use Allen's interval-based temporal logic to describe these relations. The resulting frequent patterns are used to generate temporal association rules, which convey the semantic information contained in the scene. Our overall aim is to generate rules that govern the dynamics of the scene and perform anomaly detection. We apply the proposed approach on two publicly available complex traffic datasets and demonstrate considerable improvements over the existing techniques.  相似文献   
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