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61.
    
The essential oils, isolated by distillation–extraction (DE) and hydrodistillation (H) for different extraction periods, from the aerial parts of Origanum glandulosum collected at the flowering phase in Algeria, were analysed by GC and GC‐MS. The oil yields determined by hydrodistillation attained 1.8% (v/w) and 2.7% (v/w) when extracted for 10 min and 3 h, respectively. The essential oils were dominated by the monoterpene fraction (DE 95–96% and H 86–97%), carvacrol being the main component of all oils (49–57 and 45–47% for DE and H oils, respectively). The other main components (>5%) were γ‐terpinene (DE 17–13 and H 18–13%), p‐cymene (DE 14–10 and H 17–11%) and thymol (DE 7 and H 5–7%). The composition of the glycosidic bound volatiles showed very little resemblance to the corresponding essential oil fraction. Thirteen components were detected in the glycosidic bound volatiles, only six of which were also present in the essential oil. The oxygen‐containing monoterpenes were the dominant fraction (75–97%) of the glycosidic bound volatiles, but the main component was dependent on the extraction period and not on the isolation procedure. Carvacrol (71% for DE and 61% for H) dominated the 10 min distillation, whereas thymoquinone, which was not present on the essential oil, was the dominant component in the 3 h distillation (79% for DE and 59% for H). Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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63.
In this work, TiN monolayer and TiN/TiAlN nanolayer coatings were deposited on 100C6 (AISI 52100) steel substrate by Physical vapor deposited (PVD) magnetron sputtering system. The morphological characterization was evaluated using an atomic force microscopy. The mechanical properties were determined by nanoindentation test. The adhesion was investigated by both microindentation and scratch test. The results show that the TiN/TiAlN nanolayer coating have the more rough surface and the better mechanical properties and adhesion compared to TiN monolayer coating. The effect of microstructural and mechanical proprieties on the adhesion behavior was further discussed. It was found that the improvement in adhesion of nanolayer system is in part due to the increase in plastic deformation resistance and the enhancement of mechanical properties (hardness and elastic modulus) and to the structure with a small grain size and a high number of interfaces.  相似文献   
64.
Functional graphs are a convenient representation that we have introduced to model automated production systems. They are useful for the monitoring and the supervision of manufacturing processes or other industrial processes, such as chemical processes. An approach based on relational theory and graph theory is presented in this paper. This approach allows to characterize formally structural properties of a functional graph and to map it into a set of relations translating all the complete paths existing in the initial graph. Two kinds of functional graphs are analyzed and algorithms exploiting their structures are presented. We introduce the concept of diagnosability as a system property that reflects the possibility to observe the behavior of a system with respect to faults. The diagnosability is defined and analyzed by means of computable states and mathematical relations. Propositions explaining causality relations between functions of a functional graph are given.  相似文献   
65.
Detection of edible oil adulteration is of utmost important to ensure product quality and customer protection. Campesterol, a sterol found in seed oils, represents less than 0.4% of argan oil total sterol content. Quantitative analysis of campesterol by gas chromatography of argan oil and of a mixture of argan oil and readily commercially available vegetable oils, consecutively with sterol separation, was carried out. Our study clearly demonstrated that determination of the campesterol level in argan oil (or oil presented as argan oil) can be proposed as the major analysis method to assess unambiguously argan oil purity up to 98%.  相似文献   
66.
In this work, a numerical simulation is presented for the thermo-hydrodynamic self-lubrication aspect analysis of porous circular journal bearing of finite length with sealed ends. It consists in analyzing the thermal effects on the behavior of circular porous journal bearings. The Reynolds equation of thin viscous films is used taking into account the oil leakage into the porous matrix, by applying Darcy’s law to determine the fluid flow in the porous media. The presented results are in good agreement with those cited in the literature. The effects of dimensionless permeability parameter and eccentricity ratio on performance parameters are presented and discussed. The results showed that the temperature influence on the journal bearings performance is important in some operating cases, and that a progressive reduction in the pressure distribution, in the load capacity and attitude angle is a consequence of the increasing permeability.  相似文献   
67.
The 3D compaction of a square array of spherical particles of uniform size is studied using the kinematic approach of the yield design theory. The densification is assumed to occur by plastic deformation at the mutual zone contacts between grains where the dissipation is localized. The compaction response of the array of spherical particles is considered in term of representative unit cell of the aggregate submitted to axisymmetrical loading conditions. Approximate macroscopic yield surfaces resulting from hydrostatic and closed die compaction are constructed at various stages of densifications. The size and shape of the yield surfaces depend upon the loading history as well as the relative density of the compact. Finite element simulations have also been performed in order to validate to some extent the results provided by the kinematic approach of the yield design theory and to examine the evolution of macroscopic yield surface with the degree of compaction.  相似文献   
68.
This paper proposes a supervised feature extraction approach that is capable of selecting distinctive features for the recognition of human gait under clothing and carrying conditions, thus improving the recognition performances. The principle of the suggested approach is based on the Haralick features extracted from gait energy image (GEI). These features are extracted locally by dividing vertically or horizontally the GEI locally into two or three equal regions of interest, respectively. RELIEF feature selection algorithm is then employed on the extracted features in order to select only the most relevant features with a minimum redundancy. The proposed method is evaluated on CASIA gait database (Dataset B) under variations of clothing and carrying conditions for different viewing angles, and the experimental results using k-NN classifier have yielded attractive results of up to 80% in terms of highest identification rate at rank-1 when compared to existing and similar state-of-the-art methods.  相似文献   
69.
Rhabdomyolysis results from skeletal muscle injury leading to the release of intracellular contents into blood and urine. Its diverse aetiology includes severe exercise, muscle trauma or ischaemia, metabolic disorders, infections and exposure to drugs and toxins. Known risk factors include heredity disorders of glycogen and lipid metabolism as well as a history of substance abuse. A case of rhabdomyolysis associated with exposure to opiates and benzodiazepines is described and the pathogenesis and treatment are reviewed. The rhabdomyolysis was complicated by acute renal failure; the patient fully recovered. It is suggested that rhabdomyolysis should be borne in mind in patients presenting with altered mental status, or fluid and electrolyte abnormalities, in particular, if they also give a history of substance abuse.  相似文献   
70.
Streptococcus salivarius subsp. thermophilus strain NST5 exhibited a temperature-dependent defence mechanism against the virulent bacteriophages phi B1.2 and phi A1.1. It was active at 42 degrees C but not at 30 degrees C as demonstrated by a significant increase of both plaque size and efficiency of plaquing. This defence mechanism did not affect host-dependent phage replication and did not interfere with phage adsorption to NST5. These results suggest that it interfered with phage development. The phages phi T33, phi T58, phi D1, phi T21 and phi T9, belonging to the same phage type as phi B1.2, were examined for their ability to infect NST3 and NST5. Restriction modification systems of different specificity were detected in NST3 and NST5; host-dependent phage replication was detected at 30 and 42 degrees C; an abortive defence mechanism was detected in NST5 which was active at 42 degrees C, but not 30 degrees C, and was independent of restriction modification action or interference with phage adsorption. Our investigations of phage-host interactions showed that the two Str. salivarius subsp. thermophilus strains studied avoided attack by related bacteriophages by evolving at least three different resistance systems.  相似文献   
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