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61.
This study aimed to research the influence of phenophase on the phenolic profile (phenolic acids, flavonoids and stilbenes) and related antioxidant properties of sage, one of the most characteristic plants of Dalmatian karst. The total phenol and flavonoid contents in sage leaves were determined spectrophotometrically, while the principal phenolics were determined using HPLC-RP-DAD. Antioxidant properties of this well known medicinal plant were determined as free radical scavenging activity (DPPH), ferric reducing/antioxidant power (FRAP) and by Briggs-Rauscher oscillating reaction (BR). The results strongly indicate that Dalmatian sage leaves are rich source of valuable phenolics, mainly phenolic acids, with extremely good antioxidant properties. The presence of resveratrol or its derivatives was confirmed in all extracts. The best results for total phenols and flavonoids, as well as the best antioxidant properties were obtained for May sage, while the highest amounts of catechin monomers and compounds from group of stilbenes were found in February extract.  相似文献   
62.
Tetanus and Botulinum type B neurotoxins are bacterial metalloproteases that specifically cleave the vesicle-associated membrane protein VAMP at an identical peptide bond, resulting in inhibition of neuroexocytosis. The minute amounts of these neurotoxins commonly used in experimental animals are not detectable, nor is detection of their VAMP substrate sensitive enough. The immune detection of the cleaved substrate is much more sensitive, as we have previously shown for botulinum neurotoxin type A. Here, we describe the production in rabbit of a polyclonal antibody raised versus a peptide encompassing the 13 residues C-terminal with respect to the neurotoxin cleavage site. The antibody was affinity purified and found to recognize, with high specificity and selectivity, the novel N-terminus of VAMP that becomes exposed after cleavage by tetanus toxin and botulinum toxin type B. This antibody recognizes the neoepitope not only in native and denatured VAMP but also in cultured neurons and in neurons in vivo in neurotoxin-treated mice or rats, suggesting the great potential of this novel tool to elucidate tetanus and botulinum B toxin activity in vivo.  相似文献   
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64.
We report thermopower and resistivity measurements of an YbAl3 single crystal obtained by the “self-flux” method. Our data reveal Fermi liquid behavior up to TFL = 35 K. The Kondo temperature, TK ≈ 450 K, was determined from the high temperature thermopower data. The characteristic temperature, T0, extracted from the temperature slope of the thermopower in the Fermi liquid regime is higher than the TK. We discuss a possible explanation of the obtained energy scales of YbAl3.  相似文献   
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66.
The paper deals with the numerical simulation and experimental investigations of a buried‐arc welding process on a butt‐welded plate sample. In the numerical investigations, the finite element analysis is carried out by applying the element birth and death technique in the thermal analysis, while the mechanical analysis is performed simultaneously in one step to reduce simulation time. The temperature history at two locations is recorded with thermocouples, while residual stresses are measured by using the hole‐drilling stress relaxation method at four points. The heat input efficiency for the buried‐arc welding process is determined by using a parametric analysis. The numerically obtained temperatures and residual stresses correspond very well with the experimental measurements. Furthermore, by using buried‐arc welding, 73% of the weld filler material is saved and 59% of energy, whereas the CO2 emission to the atmosphere is reduced by 83% in comparison with conventional metal active gas welding for a model of the same dimensions.  相似文献   
67.
In this paper we combine two powerful methods of symmetric cryptanalysis: rotational cryptanalysis and the rebound attack. Rotational cryptanalysis was designed for the analysis of bit-oriented designs like ARX (Addition-Rotation-XOR) schemes. It has been applied to several hash functions and block ciphers, including the new standard SHA-3 (Keccak). The rebound attack is a start-from-the-middle approach for finding differential paths and conforming pairs in byte-oriented designs like Substitution-Permutation networks and AES. We apply our new compositional attack to the reduced version of the hash function Skein, a finalist of the SHA-3 competition. Our attack penetrates more than two thirds of the Skein core—the cipher Threefish, and made the designers to change the submission in order to prevent it. The rebound part of our attack has been significantly enhanced to deliver results on the largest number of rounds. We also use neutral bits and message modification methods from the practice of collision search in MD5 and SHA-1 hash functions. These methods push the rotational property through more rounds than previous analysis suggested, and eventually establish a distinguishing property for the reduced Threefish cipher. We formally prove that such a property cannot be found for an ideal cipher within the complexity limits of our attack. The complexity estimates are supported by extensive experiments.  相似文献   
68.
Expressions for the mesh voltages caused by earth fault currents leaking from earthing grids buried in uniform, two- and three-layer soils are proposed based upon the examination of a large set of grids and soil structures using the finite element approach. Simple empirical correction factors are developed to modify the mesh voltage formulae for uniform soil to take into account the multi-layer soil structure. A comparative analysis of available expressions for uniform and two-layer soils is performed in order to check their applicability in various cases.  相似文献   
69.
The aim of this study was to determine the influence of exfoliated silicate layers on the thermal conductivity of polypropylene nanocomposites. The correlation of thermal conductivity with the degree of exfoliation is examined and compared to common mineral fillers like talcum. The results clearly show that not only the filler content but also the size and number of the main particles (specific surface) influence thermal conductivity significantly. With respect to this, the smaller the particles and the more particles are in the matrix, the higher the increase in thermal conductivity. Compared to common fillers, the increase in thermal conductivity is considerably higher with exfoliated layered silicates and directly depends on the degree of exfoliation. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers  相似文献   
70.
Introduction: Control of serum phosphate is important for patients on hemodialysis. The aim of the study was to determine if education based on phosphorus‐reducing techniques in food preparation and thermal processing, and accordingly prepared and applied diets, will lead to better outcomes than a standard education program to improve phosphate control in patients on hemodialysis. Methods: Forty‐seven patients on hemodialysis were divided between an intervention and a control group. All subjects received training about nutrition for hemodialysis patients by trained dietitian. In addition, subjects in the intervention group received additional training in phosphorus‐reducing techniques in food preparation and received two hospital meals prepared using suggested cooking methods to reduce the phosphate content of food during dialysis treatment. Serum phosphate, serum albumin, and anthropometric parameters were measured, while nPCR was calculated, at the baseline and during the 1‐year study. Findings: No differences in serum phosphate levels were observed between intervention (1.68 mmol/L [1.48–2.03]) and control group (1.88 mmol/L [1.57–2.2]) at baseline (P = 0.130). Although not statistically significant between groups the mean reduction was more apparent in the intervention group (?0.3 mmol/L (?0.4 to 0.1) vs. ?0.2 (?0.5 to 0.1)), and lead to significantly reduction of phosphate binder therapy. During the study, the nPCR and anthropometric status of the patients did not change significantly. Discussion: Providing additional education to hemodialysis patients on the specific cooking methods and accordingly prepared meals may decrease serum phosphate levels without significantly affecting nutritional status which may be useful in helping to prevent and treat hyperphosphatemia.  相似文献   
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