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101.
Extruded cereal snacks are usually deficient in protein, mineral ingredients, valuable fatty acids. With the rise of health awareness among consumers, food manufacturers and scientists are pressed to take measures in order to develop new functional/health‐beneficial foods. The aim of this work was to manufacture extruded crisps enriched with α‐linolenic acid (obtained from linseed oil) and to observe whether storage of the product for the period of 6 months would cause its disqualification, primarily due to its sensory properties and secondarily due to its chemical properties. The research demonstrated that the addition of linseed oil to corn crisps at the amount of 5 % enables to obtain functional corn crisps containing over 2 g of ALA in a portion of 100 g even after 6 months of storage at room temperature. ALA‐enriched crisps maintain the original sensory profile after 6 months of storage and their sensory profile is similar to the profile of crisps without the addition of linseed oil if they are packed in barrier packaging filled 100 % with argon. Therefore, they may be a healthier alternative to typical corn crisps.  相似文献   
102.
The influence of the basalt powder (BP) on mechanical properties as well as on thermal stability and flammability of the isotactic polypropylene (iPP) composites was investigated. Thermo‐mechanical stability of the pure polypropylene and composite materials containing from 5 up to 40 wt% BP was defined in static and dynamic testing conditions with the use of the heat distortion temperature measurement, vicat softening point temperature test, and dynamic mechanical thermal analysis. All measurements showed, unequivocally, a significant improvement of thermo‐mechanical stability of the composite materials which was directly related to an increasing amount of inorganic filler. A research conducted on the mechanical properties revealed that stiffness and hardness of polypropylene‐based composites was affected by the addition of the filler, leading to a strong increase of both mechanical parameters. Moreover, the application of thermogravimetric analysis and cone calorimetry measurements allowed to determine the composites with highest thermal stability, which was dependent on the concentration of the filler. Changes observed in the polypropylene‐based composites properties were related to an increase of thermal diffusivity caused by presence of the BP measured by modified Angstrom method. POLYM. ENG. SCI., 59:E71–E79, 2019. © 2018 Society of Plastics Engineers  相似文献   
103.
Geometrical aspects of optimum truss like structures   总被引:1,自引:1,他引:0  
The authors obtain graphical rules to construct discrete optimum structures without the use of analytical or numerical optimization processes. Structures investigated are limited to those having a single loaded point and two points of support (three-point problems). The cost of structures is assumed to be proportional to their theoretical weight and to a performance index. The performance index is derived using the Lagrange multiplier method to minimize deflection of the loaded point with the given total volume of material. Solutions of simple problems, obtained with a gradient-based minimizing procedure, lead through a series of observations to the generalized solution of optimum discrete structures. The authors determine that optimum discrete structure for three-point problems can be described using the angles between four truss elements connected in every non-support node. These four angles are the same for every node of the structure.  相似文献   
104.
This article presents the current state of knowledge on the issue of supporting classic welding processes by mechanical vibrations. Selected results of own research on the impact of mechanical vibration on the structure and properties of welding structures are also discussed.  相似文献   
105.
The paper presents a synthesis of poly(l-lactide) with bacteriostatic properties. This polymer was obtained by ring-opening polymerization of the lactide initiated by selected low-toxic zinc complexes, Zn[(acac)(L)H2O], where L represents N-(pyridin-4-ylmethylene) tryptophan or N-(2-pyridin-4-ylethylidene) phenylalanine. These complexes were obtained by reaction of Zn[(acac)2 H2O] and Schiff bases, the products of the condensation of amino acids and 4-pyridinecarboxaldehyde. The composition, structure, and geometry of the synthesized complexes were determined by NMR and FTIR spectroscopy, elemental analysis, and molecular modeling. Both complexes showed the geometry of a distorted trigonal bipyramid. The antibacterial and antifungal activities of both complexes were found to be much stronger than those of the primary Schiff bases. The present study showed a higher efficiency of polymerization when initiated by the obtained zinc complexes than when initiated by the zinc(II) acetylacetonate complex. The synthesized polylactide showed antibacterial properties, especially the product obtained by polymerization initiated by a zinc(II) complex with a ligand based on l-phenylalanine. The polylactide showed a particularly strong antimicrobial effect against Pseudomonas aeruginosa, Staphylococcus aureus, and Aspergillus brasiliensis. At the same time, this polymer does not exhibit fibroblast cytotoxicity.  相似文献   
106.
2D culture as a model for drug testing often turns to be clinically futile. Therefore, 3D cultures (3Ds) show potential to better model responses to drugs observed in vivo. In preliminary studies, using melanoma (B16F10) and renal (RenCa) cancer, we confirmed that 3Ds better mimics the tumor microenvironment. Here, we evaluated how the proposed 3D mode of culture affects tumor cell susceptibility to anti-cancer drugs, which have distinct mechanisms of action (everolimus, doxorubicin, cisplatin). Melanoma spheroids showed higher resistance to all used drugs, as compared to 2D. In an RCC model, such modulation was only observed for doxorubicin treatment. As drug distribution was not affected by the 3D shape, we assessed the expression of MDR1 and mTor. Upregulation of MDR1 in RCC spheroids was observed, in contrast to melanoma. In both models, mTor expression was not affected by the 3D cultures. By NGS, 10 genes related with metabolism of xenobiotics by cytochrome p450 were deregulated in renal cancer spheroids; 9 of them were later confirmed in the melanoma model. The differences between 3D models and classical 2D cultures point to the potential to uncover new non-canonical mechanisms to explain drug resistance set by the tumor in its microenvironment.  相似文献   
107.
108.
This review highlights the recent developments in nucleic acid-based based materials for biomedical applications and functional devices. DNA and RNA are anionic macromolecules composing sugar-phosphate backbone, which usually structure as rod-like double helix with base pair stacking. Electrostatic interactions are the main components in the complex formed between anionic nucleic acid and cationic molecule. These nucleic acid-based biopolymers have significant potential as functional materials for drug delivery, biosensors, and a scaffold for many biodegradable materials.  相似文献   
109.
Flow thermomechanics in reactive porous media is of importance in industry including the thermal processing of fossil fuel (coking understood as a slow pyrolysi...  相似文献   
110.
Nonsteroidal anti-inflammatory drugs (NSAIDs) are considered to be therapeutics in cancer prevention because of their inhibitory effect on cyclooxygenases (COX), which are frequently overexpressed in many types of cancer. However, it was also demonstrated that NSAIDs provoked a proapoptotic effect in COX knocked-out cancer cells. Here, we suggest that this group of drugs may provoke antineoplastic activity through the activation of PPARγ, which induces proline dehydrogenase/proline oxidase (PRODH/POX)-dependent apoptosis. PRODH/POX is a mitochondrial enzyme that catalyzes proline degradation, during which ATP or reactive oxygen species (ROS) are generated. We have found that NSAIDs induced PRODH/POX and PPARγ expressions (as demonstrated by Western Blot or immunofluorescence analysis) and cytotoxicity (as demonstrated by MTT, cytometric assay, and DNA biosynthesis assay) in breast cancer MCF7 cells. Simultaneously, the NSAIDs inhibited collagen biosynthesis, supporting proline for PRODH/POX-induced ROS-dependent apoptosis (as demonstrated by an increase in the expression of apoptosis markers). The data suggest that targeting proline metabolism and the PRODH/POX–PPARγ axis can be considered a novel approach for breast cancer treatment.  相似文献   
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