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1.
Hams from Landrace, Duroc and Hampshire pigs slaughtered at ages 6, 7.5 and 9 months were processed to generate Norwegian Parma‐style hams. Lipid contents and the compositions of fatty acid classes (ΣSFA, ΣMUFA, ΣPUFA) within neutral lipids, phospholipids and free fatty acids were determined. Small differences in lipid degradation and composition of the classes were revealed. However, significant sensory differences related to lipids were observed. Breed was more important than age. Dry‐cured Hampshire hams gave a more intense mature odour that may be associated with higher overall lipid degradation. Unexpectedly, these hams also demonstrated high juiciness and tenderness, which could be related to the melting characteristics of the fat. Dry‐cured Duroc hams showed a higher susceptibility towards rancidity, presumably associated with preferential oxidation of n‐6 fatty acids relative to C18:1 n‐9. Dry‐cured Landrace hams showed the lowest juiciness and tenderness, likely due to their lower fat content (marbling).  相似文献   
2.
Insoluble deposit formed in aromatic bitters produced from alcoholic extracts of about 30 different botanical materials with a dry matter content of 1.67% and 38 vol% alcohol and a characteristic astringent flavour was shown by13C NMR spectroscopy to be a coprecipitate of plant polyphenols, proteins and carbohydrates. The polyphenols in the deposit were flavonoids such as anthocyanidins and anthocyanins, with glucose as the principal carbohydrate and derivatives of cinnamic acid. The deposit formation in the aromatic bitters was accelerated by addition of the radical initiator 2,2′-azobis(2-amidinopropane) dihydrochloride or by addition of hydrogen peroxide in combination with iron(III) nitrate and ascorbic acid as a Fenton reagent. Polymerization of catechin and pelargonidin was shown, in model experiments, to be oxidative and to be accelerated by exposure to light. A mechanism involving oxidative polymerization of polyphenols followed by coprecipitation of polymerized polyphenols, proteins and carbohydrates is proposed for formation of deposits in alcoholic beverages of the bitters type.  相似文献   
3.
There are two popular approaches to specifying the semantics of process algebras: labelled transition semantics and reaction semantics. While the notion of free name is rather unproblematic for labelled transition semantics this is not so for reaction semantics in the presence of a structural congruence for unfolding recursive declarations.We show that the standard definition of free name is not preserved under the structural congruence. We then develop a fixed point approach to the set of free names and show that it is invariant under the structural congruence.  相似文献   
4.
The past decade revealed that cell identity changes, such as dedifferentiation or transdifferentiation, accompany the insulin-producing β-cell decay in most diabetes conditions. Mapping and controlling the mechanisms governing these processes is, thus, extremely valuable for managing the disease progression. Extracellular glucose is known to influence cell identity by impacting the redox balance. Here, we use global proteomics and pathway analysis to map the response of differentiating human pancreatic progenitors to chronically increased in vitro glucose levels. We show that exogenous high glucose levels impact different protein subsets in a concentration-dependent manner. In contrast, regardless of concentration, glucose elicits an antipodal effect on the proteome landscape, inducing both beneficial and detrimental changes in regard to achieving the desired islet cell fingerprint. Furthermore, we identified that only a subgroup of these effects and pathways are regulated by changes in redox balance. Our study highlights a complex effect of exogenous glucose on differentiating pancreas progenitors characterized by a distinct proteome signature.  相似文献   
5.
Metallurgical and Materials Transactions A - The effect of 0.03 and 0.08 at. pct Fe additions on the formation of secondary phases in an Al–1.1Mg–0.5Cu–0.3Si at. pct alloy was...  相似文献   
6.
Broadcast semantics poses significant challenges over point-to-point communication when it comes to formal modelling and analysis. Current approaches to analysing broadcast networks have focused on fixed connectivities, but this is unsuitable in the case of wireless networks where the dynamically changing network topology is a crucial ingredient. In this paper, we develop a static analysis that automatically constructs an abstract transition system, labelled by actions and connectivity information, to yield a mobility-preserving finite abstraction of the behaviour of a network expressed in a process calculus with asynchronous local broadcast. Furthermore, we use model checking based on a 3-valued temporal logic to distinguish network behaviour which differs under changing connectivity patterns.  相似文献   
7.
The ambient oxygen ingress rate (AOIR) method is an alternative or supplementary method to Ox‐Tran for measuring the oxygen transmission rate (OTR) of packages. The method has high capacity, requires relatively inexpensive equipment and measures OTR at different temperatures and humidity conditions. The aim of this study was, on the one hand, to study the effect of temperature on the OTR for packages produced from different polymer materials and laminates, and on the other hand to evaluate the suitability of the AOIR method at freezing temperature conditions. The OTR for 10 packages with different polymer compositions was measured at 23°C, 6°C and ?25°C. The AOIR method was shown to be a reliable test method for measuring OTR of packages at all the applied test conditions, also at frozen storage temperature. The OTR for the packages decreased with lower temperatures, especially for the packages with the highest OTR values at 23°C. In order to avoid higher packaging expenses than necessary to obtain the required shelf‐life for different food products, the OTR for alternative packages should be measured at the temperature and humidity conditions of intended use. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
8.
Summary Three varieties ofCurcuma longa andC. aromatica were investigated during a growth period of 17 weeks with respect to the content of curcuminoids in the bulbs and fingers. A decrease in pigment production as a function of maturity of the rhizomes was observed. The total content of curcuminoids was equal inC. longa andC. aromatica, but with a slight difference in distribution between the fingers and bulbs in the two species. Taking the biomass into account, the fingers will be more beneficial for the isolation of curcuminoids than the respective bulbs.
Studien über Curcumin und Curcuminoide XXI. Unterschiede des Gehaltes an Curcuminoiden bei Curcuma longa L. und Curcuma aromatica Salisb. aus Indien während einer Saison
Zusammenfassung Drei Typen vonCurcuma longa undC. aromatica wurden während einer Wachstumsperiode von 17 Wochen auf ihren Curcuminoidgehalt in den Knollen und im Wurzelstock untersucht. Eine Abnahme der Pigmentproduktion in Abhängigkeit von dem Entwicklungsstadium der Rhizome wurde festgestellt. Der Gesamtgehalt an Curcuminoiden beiC. longa undC. aromatica war der gleiche, doch bestand ein geringer Unterschied in der Verteilung dieser zwischen Knolle und Wurzelstock bei den beiden Spezies. Bei Betrachtung der Biomasse ist der Wurzelstock für die Isolation von Curcuminoiden besser geeignet als die Knollen.
  相似文献   
9.
The aim of this study was to measure the variation in dietary fibre (DF) content and composition among different rye varieties grown in the same location in three successive years and to estimate the contributions of genotype and harvest year to this variation. The study included grain from 19 different varieties of rye, of which seven varieties were analysed in all three years. The content of total DF in all samples ranged from 147 to 209 g kg?1 dry matter (dm), with 34–66 g kg?1 being water‐extractable (WE) DF and 108–159 g kg?1 being water‐unextractable (WUE) DF. The main DF component was arabinoxylan (AX) with a content of 80–121 g kg?1 dm, of which 26–41 g kg?1 dm was WE AX. The ratio of arabinose to xylose (ara/xyl) of total AX ranged from 0.59 to 0.69. The content of β‐glucan was 13–22 g kg?1 dm and that of fructan was 45–64 g kg?1 dm. Analysis of the data from seven varieties and three harvest years showed a highly significant influence of harvest year on most DF components. Significant genotype effects were found for the contents of total DF, total AX, β‐glucan and fructan and for the ara/xyl ratio of total and WUE AX. Estimation of variance components showed that yearly variations in the contents of total DF, total AX, WUE DF, WUE AX and β‐glucan were generally higher (27–55% of total variance) than genotype effects (14–19%). The ara/xyl ratio of total and WUE AX showed a high influence of genotype (46 and 43% respectively). Non‐adapted rye varieties with small kernel size had the highest contents of total DF and total AX. The content of β‐glucan was positively correlated with kernel weight (r = 0.68), whereas no overall correlation was found between kernel size and the content of DF. As a conclusion, the variation in DF content and composition in this study was significantly influenced by both harvest year and rye genotype. © 2002 Society of Chemical Industry  相似文献   
10.
Foodborne illness continues as a considerable threat to public health. Despite improved hygiene management systems and increased regulation, pathogenic bacteria still contaminate food, causing sporadic cases of illness and disease outbreaks worldwide. For many centuries, microbial antagonism has been used in food processing to improve food safety. An understanding of the mode of action of this microbial antagonism has been gained in recent years and potential applications in food and feed safety are now being explored. This review focuses on the potential opportunities presented, and the limitations, of using microbial antagonism as a biocontrol mechanism to reduce contamination along the food chain; including animal feed as its first link. © 2014 Society of Chemical Industry  相似文献   
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