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1.
Variability for oil and fatty acid composition in castorbean varieties   总被引:1,自引:0,他引:1  
Thirty-six castorbean varieties were surveyed for oil and fatty acid composition, in order to determine variability of these seed compounds. A large variability of seed oil percentage was observed, ranging from 39.6 to 59.5%. Concerning the fatty acids, little variability was observed for ricinoleic acid, which was the most abundant in the oil, ranging from 83.65 to 90.00%. The other fatty acids appeared in small concentrations and showed a small range: 0.87 to 2.35, 0.68 to 1.84, 2.96 to 5.64, 3.19 to 5.98, and 0.34 to 0.91%, for palmitic, stearic, oleic, linoleic, and linolenic acid, respectively. Non-significant correlations were observed between fatty acids and seed oil percentage. However, significant correlations were observed among fatty acid concentrations: positive and negative ones. These significant correlations could be associated with the biosynthetic pathways of the fatty acids, which are not fully elucidated. They suggest, however, that selection for a particular fatty acid will tend to increase those positively correlated, and decrease those negative ones. Selection and plant breeding techniques could then be applied to modify the oil content of the castorbean seeds, considering the variability observed. For the fatty acid composition, however, the variability was not large enough to make substantial changes in their concentrations by selection procedures. More varieties should be surveyed to find out if such variability is available.  相似文献   
2.
Magnetic susceptibility from 300 to 900 K, room temperature hysteresis cycles and saturation magnetization were investigated in screen printed and fired NiCo-based layers prepared at various peak temperatures. A bulk NiCo metal sheet of comparable composition was also studied. Values of the magnetic polarization J of 0.28 and 0.435 T were obtained (at 200 kA/m) for films prepared at 750 and 950°C, respectively, in contrast with J=0.98 T for the bulk alloy. In addition, the magnetoresistive responses of the layers and the sheet were plotted. These data suggest that strains, pores and lack of composition homogeneity in the films concur in affecting their magnetic properties, and are responsible for their reduced magnetoresistance anisotropy (e.g. ca. 4% for films as compared to ca. 8% for the bulk alloy at H=80 kA/m).  相似文献   
3.
A modified block replacement policy is examined with the purpose of excluding the wastefulness caused by the property that almost new items might be sometimes replaced at planned replacement times under the ordinary block replacement policy. This modified policy can be stated as follows: 1) Operating items are replaced by new items at times kT (k = 1,2,...), 2) If operating items fail in [(k - 1)T, kT - v), they are replaced by new items, and in [kT - v, kT), they are replaced by less reliable items than new items. Numerical comparisons between the proposed policy and the ordinary block replacement policy are carried out for Weibull distribution.  相似文献   
4.
Food Science and Biotechnology - Edible antimicrobial coating produced from chitosan (CS) and its derivative was applied to improve the shelf life of fresh strawberries at 10 °C....  相似文献   
5.
This paper proposes Mantel-Haenszel-type statistics for testing whether a new treatment is at least as effective as the standard treatment in comparative binomial trials. The null hypotheses considered are of a specified nonzero difference and of a ratio not equal to unity. It is shown that we may also use these tests for testing the equivalence of two treatments.  相似文献   
6.
For part I see ibid., vol.41, no.12, pp.2357-62 (1994). This paper reports the studies of the inversion layer mobilities in n-channel MOSFET's fabricated on Si wafers with three surface orientations ((100), (110), and (111)) from the viewpoint of the universal relationship against the effective field, Eeff(=q(Ndpl+η·Ns )/εSi). It is found that the universality does hold for the electron mobilities on (110) and (111), when the value of η is taken to be 1/3, different from the electron mobility on (100), where η is 1/2. Also, the Eeff dependence of the electron mobility is found to differ among (100), (110), and (111) surfaces. This is attributed to the differences in the Eeff dependence of the mobility limited by surface roughness scattering among the orientations. The origins of Eeff and η are discussed on the basis of the relaxation time approximation for a 2DEG (2-dimensional electron gas). While the surface orientation dependence of η in phonon scattering can be understood in terms of the subband occupation, it is found that the theoretical formulation of surface roughness scattering, used currently, needs to be refined in order to explain the differences in Eeff dependence and the value of η among the three orientations  相似文献   
7.
The cyclopropene acid groups in cottonseed oil can be modified by a light hydrogenation which will not produce large amounts oftrans isomers or lower the iodine value to a significant extent. Optimum conditions, as indicated by this investigation, are 105-115C, 20 psig hydrogen pressure, 0.1% electrolytic nickel as catalyst, and a low hydrogen-dispersion rate. Under milder conditions of hydrogenation the elimination of the cyclopropenes was accompanied by a lower formation oftrans isomers and a lower hydrogenation of noncyclopropenes, but the time required increased. In one hydrogenation carried out with commercial nickel catalyst, the 0.4% of malvalic acid groups in the cottonseed oil was hydrogenated completely whereas the iodine value was reduced by only 1.7 units and only 2.1% oftrans isomers was formed. AVinterization of cottonseed oils which had been hydrogenated to the point of eliminating their response to the Halphen test and in which only small amounts of saturated acid groups andtrans isomers had been formed gave yields equal to or better than those of the original oil. Hydrogénation actually increased the ease of winterization. 2 So. Utiliz. Ees. Dev. Div, ARS, USDA.  相似文献   
8.
When choosing hair dyes, it is natural for the user to assume that the final hair color will resemble the color indicated on the product container or color chart. Often, however, the result is quite different. The ability to accurately predict resulting hair color after dyeing is essential, but not easy to attain because hair varies significantly from person to person. In this paper, a new method for predicting the dyed hair state is proposed. Our method is based on a model, where the observed final color consists of contribution from three layers of the hair structure: a melanin-containing layer, a bleached layer and a pigment-colored layer. A method for predicting the final color from responses in each layer is introduced. In this method, response formulae for each layer are derived from the energy balance, and the predicted hair color after dyeing is obtained by calculating the each equation assuming that the hair state before dyeing is solely because of the contribution from the melanin-containing layer. In addition, a small measuring apparatus utilizing this prediction method was developed and the effectiveness of our method demonstrated by data obtained before and after the hair dyeing.  相似文献   
9.
E-beam recrystallization has been applied to the fabrication of a three-layer processor. The seed structure and the E-beam conditions were successfully optimized so that a large-area SOI as wide as 1 mm was recrystallized without void generation with no damage to underlying devices. The actual SOI area in the device, 850×1100 μm, was recrystallized with one E-beam scan by aligning its position. The three-layer image processor was capable of visual image sensing with a feature outline extraction in a parallel processing manner. Normal operations of the fundamental functions have been confirmed, demonstrating the feasibility of E-beam recrystallization for three-dimensional IC application  相似文献   
10.
This study evaluated Staphylococcus aureus growth and subsequent staphylococcal enterotoxin A production in tryptone soy broth and on ready‐to‐eat cooked fish paste at 12 to 37 °C, as well as cross‐contamination between stainless steel, polyethylene, and latex glove at room temperature. A model was developed using Barany and Roberts's growth model, which satisfactorily described the suitable growth of S. aureus with R2‐adj from 0.94 to 0.99. Except at 12 °C, S. aureus cells in TSB presented a lag time lower (14.64 to 1.65 h), grew faster (0.08 to 0.31 log CFU/h) and produced SEA at lower cell density levels (5.65 to 6.44 log CFU/mL) compare to those inoculated on cooked fish paste with data of 16.920 to 1.985 h, 0.02 to 0.23 log CFU/h, and 6.19 to 7.11 log CFU/g, respectively. Staphylococcal enterotoxin type A (SEA) visual immunoassay test showed that primary SEA detection varied considerably among different storage temperature degrees and media. For example, it occurred only during exponential phase at 30 and 37 °C in TSB, but in cooked fish paste it took place at late exponential phase of S. aureus growth at 20 and 25 °C. The SEA detection test was negative on presence of S. aureus on cooked fish paste stored at 12 and 15°C, although cell density reached level of 6.12 log CFU/g at 15 °C. Cross‐contamination expressed as transfer rate of S. aureus from polyethylene surface to cooked fish paste surface was slower than that observed with steel surface to cooked fish paste under same conditions. These results provide helpful information for controlling S. aureus growth, SEA production and cross‐contamination during processing of cooked fish paste.  相似文献   
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