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71.
This study was done to investigate whether white cabbage contained polysaccharides with immunostimulatory activity using the complement-fixing test as an indicator. The main polysaccharide isolated was of pectin nature. Methanolysis and (13)C-NMR showed that the polymers consisted of highly esterified alpha-galactopyranoside (alpha-GalpA), significant amounts of alpha-arabinose furanoside (alpha-Araf), beta-Galp and lesser amounts of rhamnose in the pyranose form (Rhap) and xylose in the pyranose form (Xylp). Linkage analyses showed that the alpha-GalpA residues were mainly 1,4-linked with small amounts of 1,3,4-linkages. The alpha-Araf residues were mainly terminally (t)- and 1,5-linked, whereas beta-Galp was t-, 1,3-, 1,6-, and 1,3,6-linked. Positive Yariv reaction indicated polymers with arabinogalactan type 2 like structures. alpha-Rhap was mainly present as 1,2- and 1,2,4-linked residues and Xylp was t- and 1,4-linked. The molecular weight varied greatly and was from 10 to 150 kDa. Cabbage polymers had biological activity and this complement-fixing activity was greatly affected by hydrolytic removal of Araf from pectic side chains.  相似文献   
72.
In this paper the connection between massM, resistance and commute time for random walks on graphs is further explored, and the relation=2M · is proved. An extension of the result is made to multigraphs, which are an extension of the graph concept where a black box is treated like an edge.  相似文献   
73.
This paper focuses on identifying segments of consumers based on their use of and trust in information sources about fish. Cross-sectional data were collected through the SEAFOODplus pan-European consumer survey (n = 4786) with samples representative for age and region in Belgium, the Netherlands, Denmark, Spain and Poland. Three distinct clusters, based on use of and trust in fish information sources, were identified: Sceptic (24.0%), Enthusiast (41.4%) and Confident (34.6%). Those consumer segments differed significantly with respect to use of and interest in information cues on fish labels, knowledge and behaviour towards fish, and socio-demographic profile. Recommendations for the use of multiple sources targeted to a particular audience’s interest and behavioural profile were formulated.  相似文献   
74.
A polyethylene glycol (PEG) stationary phase was evaluated for the separation of mono‐trans isomers of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) methyl esters. The resolution patterns were compared to patterns achieved with previously applied conditions on a cyanopropyl phase. There were no overlaps between all‐cis EPA/DHA and their mono‐trans isomers on the PEG phase. Because of overlap between 22:0 and 22:1 isomers, the PEG column is not a good choice for analyses of EPA trans isomers in crude fish oils. However, if the saturated and monounsaturated fatty acids are not present in significant amounts, PEG can be a better choice than cyanopropyl columns.  相似文献   
75.
The design and construction of an ellipsometer based on a fixed-wavelength rotating-retarder Stokes polarimeter is described. Details are provided for an automated calibration scheme that provides two advantages for its operation. The first allows the phase of the lock-in amplifiers to be set based on the raw data, without a known calibration sample. The second illustrates that the relative amplitude of the acquired signals may also be calibrated in a similar manner. As an illustration, the refractive index and thickness of a glass cover slide are determined over a range of incident angles.  相似文献   
76.
Brain tissue modelling has been an active area of research for years. Brain matter does not follow the constitutive relations for common materials and loads applied to the brain turn into stresses and strains depending on tissue local morphology. In this work, a hyperviscoelastic fibre-reinforced anisotropic law is used for computational brain injury prediction. Thanks to a fibre-reinforcement dispersion parameter, this formulation accounts for anisotropic features and heterogeneities of the tissue owing to different axon alignment. The novelty of the work is the correlation of the material mechanical anisotropy with fractional anisotropy (FA) from diffusion tensor images. Finite-element (FE) models are used to investigate the influence of the fibre distribution for different loading conditions. In the case of tensile–compressive loads, the comparison between experiments and simulations highlights the validity of the proposed FA–k correlation. Axon alignment affects the deformation predicted by FE models and, when the strain in the axonal direction is large with respect to the maximum principal strain, decreased maximum deformations are detected. It is concluded that the introduction of fibre dispersion information into the constitutive law of brain tissue affects the biofidelity of the simulations.  相似文献   
77.
The purpose of this paper is to give a macro-picture of collaboration in research groups and networks across all academic fields in Norwegian research universities, and to examine the relative importance of membership in groups and networks for individual publication output. To our knowledge, this is a new approach, which may provide valuable information on collaborative patterns in a particular national system, but of clear relevance to other national university systems. At the system level, conducting research in groups and networks are equally important, but there are large differences between academic fields. The research group is clearly most important in the field of medicine and health, while undertaking research in an international network is most important in the natural sciences. Membership in a research group and active participation in international networks are likely to enhance publication productivity and the quality of research.  相似文献   
78.
Injuries to the head caused by ballistic impacts are not well understood. Ballistic helmets provide good protection, but still, injuries to both the skull and brain occur. Today there is a lack of relevant test procedure to evaluate the efficiency of a ballistic helmet. The purpose of this project was (1) to study how different helmet shell stiffness affects the load levels in the human head during an impact, and (2) to study how different impact angles affects the load levels in the human head. A detailed finite element (FE) model of the human head, in combination with an FE model of a ballistic helmet (the US Personal Armour System Ground Troops’ (PASGT) geometry) was used. The head model has previously been validated against several impact tests on cadavers. The helmet model was validated against data from shooting tests. Focus was aimed on getting a realistic response of the coupling between the helmet and the head and not on modeling the helmet in detail. The studied data from the FE simulations were stress in the cranial bone, strain in the brain tissue, pressure in the brain, change in rotational velocity and translational and rotational acceleration. A parametric study was performed to see the influence of a variation in helmet shell stiffness on the outputs from the model. The effect of different impact angles was also studied. Dynamic helmet shell deflections larger than the initial distance between the shell and the skull should be avoided in order to protect the head from the most injurious threat levels. It is more likely that a fracture of the skull bone occurs if the inside of the helmet shell strikes the skull. Oblique ballistic impacts may in some cases cause higher strains in the brain tissue than pure radial ones.  相似文献   
79.
We have investigated the use of microwave heating and radiometry to safely heat urine inside a pediatric bladder. The medical application for this research is to create a safe and reliable method to detect vesicoureteral reflux, a pediatric disorder, where urine flow is reversed and flows from the bladder back up into the kidney. Using fat and muscle tissue models, we have performed both experimental and numerical simulations of a pediatric bladder model using planar dual concentric conductor microstrip antennas at 915 MHz for microwave heating. A planar elliptical antenna connected to a 500 MHz bandwidth microwave radiometer centered at 3.5 GHz was used for noninvasive temperature measurement inside tissue. Temperatures were measured in the phantom models at points during the experiment with implanted fiberoptic sensors, and 2-D distributions in cut planes at depth in the phantom with an infrared camera at the end of the experiment. Cycling between 20 s with 20 Watts power for heating, and 10?s without power to allow for undisturbed microwave radiometry measurements, the experimental results show that the target tissue temperature inside the phantom increases fast and that the radiometer provides useful measurements of spatially averaged temperature of the illuminated volume. The presented numerical and experimental results show excellent concordance, which confirms that the proposed system for microwave heating and radiometry is applicable for safe and reliable heating of pediatric bladder.  相似文献   
80.
Objective: According to psychoanalytic theory, interpretation of transference leads to increased insight that again leads to improved interpersonal functioning over time. In this study, we performed a full mediational analysis to test whether insight gained during treatment mediates the long-term effects of transference interpretation in dynamic psychotherapy. Method: This study is a randomized clinical trial with a dismantling design. One hundred outpatients seeking psychotherapy for depression, anxiety, personality disorders, and interpersonal problems were randomly assigned to 1 year of weekly sessions of dynamic psychotherapy with transference interpretation or to the same type and duration of treatment with the same therapists but without the use of transference interpretation. Interpersonal functioning and insight were measured pretreatment, posttreatment, and 1 year and 3 years after treatment termination. Results: Contrary to common expectation, patients with a life-long pattern of low quality of object relations and personality disorder pathology profited more from therapy with transference interpretation than from therapy with no transference interpretation. This long-term effect was mediated by an increase in the level of insight during treatment. Conclusions: Insight seems to be a key mechanism of change in dynamic psychotherapy. Our results bridge the gap between clinical theory and empirical research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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