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1.
A new method to reduce the peak-to-average power ratio (PAPR) in space division multiplexing systems applying orthogonal frequency division multiplexing is proposed. The method applies spatial shifting to partial transmit sequences to achieve a decreased PAPR on all transmit branches.  相似文献   
2.
Twenty-four veal calves were stunned with a captive bolt. Twelve calves were shackled by the left, the other twelve by the right hindleg. Approximately 1 min after sticking, six carcasses of each of these subgroups were stimulated electrically with equipment relying on a combined high (3000 V, 0·83 pulses s(-1), 1·5 ms duration) and low 35 V, 14 pulsess(-1)) voltage action. The remaining carcasses were left unharmed. At 24 h post-mortem hindquarters were boned to commercial primal cuts. Surrounding connective tissue and cut-up surfaces of primals as well as certain locations vulnerable for blood splash were further dissected. Neither electrical stimulation nor shackling by either of the hindlegs significantly affected the prevalence and severity of blood splash. Post-mortem factors promoting blood splash and possibly related to electrical stimulation and shackling are discussed. At 7 days post-mortem the sensory meat quality was assessed. In general, electrical stimulation did not significantly affect waterbinding and colour characteristics in longissimus (M. longissimus dorsi) and semimembranosus samples. Sarcomere lengths were similar in stimulated and control groups in longissimus but not in semimembranosus muscle. In both muscles shear force values were lower after electrical stimulation. In general, neither longissimus nor semimembranosus samples excised ipsilaterally from the shackled leg side exhibited differences in tenderness and sarcomere length. It is concluded that shackling by one leg or the other does not interfere with the tenderising effect of electrical stimulation.  相似文献   
3.
The effects of time of boning and storage period on creatine kinase (CK) activity, transmission value, drip losses and water-holding capacity (WHC) measured by various methods was investigated. At 40 min post-mortem 30 pig carcasses with pH values > 6·2 in the loin were selected. The right loin of each carcass was hot boned and vacuum packaged immediately. The left loin was cold boned and packaged after overnight chilling at 2 ± 2°C. After 1, 5 and 12 days of storage at 0 ± 1°C, 10 hot- and cold-boned loins were unpacked and sampled. Time of boning did not affect drip losses. At 1 day post-mortem the CK activity was higher in hot- than in cold-boned pork. Sarcomere lengths were not affected by time of boning. The WHC was investigated by two controlled methods. A filter-paper press method was not sensitive enough to assess differences in WHC of hot- vs cold-boned pork. The results of a gravimetric method depended on the sample location. Results of the gravimetric test decreased with increasing storage periods. The results suggest that under the experimental conditions the chilling rates of hot-boned vs carcass-attached muscles were similar.  相似文献   
4.
The occurrence of Salmonella in meat from game hunted in Europe is reviewed, with a focus on Central Europe. Prevalence in fecal samples is different according to region and game species, ranging from < 5 (wild ruminants) to ca. 20% (wild boar). The pathogen is rarely recovered from carcasses or meat cuts of wild ruminants (< 1%). Prevalences on wild boar carcasses have been reported to range from < 1 to ca. 7%, the tonsils presumably constituting a main reservoir on the eviscerated carcass. On meat cuts from game, recent German and EU (EFSA) reports indicate a prevalence of < 1%. A number of Salmonella enterica serovars can be isolated, with highest prevalences of S. Typhimurium and S. Enteritidis. Persistence of these pathogens in wildlife is a less pressing issue for biology and wildlife conservation than for public health experts, which has been recognized in the framework of zoonoses legislation. On one hand, wildlife is exposed to salmonellae originating from farm animals and humans, and on the other hand, game can be a source of Salmonella in farm animals. Breeding game under intensified conditions (farmed game) as well as extensive breeding of farm animals, notably pigs, can create new epidemiological situations. The pathway of Salmonella from intestinal content of the live animal to individual meat cuts can be described in qualitative terms, yet the relative contribution of the various factors remains to be quantified, which complicates proper risk assessment. Control of Salmonella in the game meat chain is in part based on Good Hygiene Practice from killing and evisceration to chilling and skinning, whereas more detailed data are needed in order to allow risk-based meat inspection.  相似文献   
5.
This study was performed to evaluate the resistance rate against antimicrobials of food isolates of the five major food-borne pathogens to compare these and to possibly distinguish a pattern. A total of 922 samples of the major meat species (pork, beef and poultry) were analysed for thermophilic Campylobacter, Salmonella, Yersinia enterocolitica, pathogenic Escherichia coli and Listeria monocytogenes. Isolates were subjected to antimicrobial resistance testing by the disc diffusion method. Roughly the same overall rate of resistance was identified for thermophilic Campylobacter, Salmonella and pathogenic E. coli. Resistance to quinolones and tetracycline was determined most frequently. In contrast, food isolates of Y. enterocolitica and L. monocytogenes were rarely tested resistant. The significance of our findings is that resistance rates in enteric bacteria seem to be much higher than in pathogens found in a variety of environments, closely associated to the host environment.  相似文献   
6.
This paper describes and illustrates different configurations of the interface between new product development and production processes, including both intra–firm and inter–firm interfaces. These configurations are partly based on a process view of product innovation and partly on a structural view of product innovation. In addition to this typology of interfaces some integration mechanisms are described. The typology will serve as a basis for further research aimed at identifying consistent configurations of the different types of integration mechanisms that are available for industry to increase the effectiveness and efficiency of product innovation processes.  相似文献   
7.
8.
The application of fan-beam antennas in high-speed indoor wireless communication systems operating in the 60 GHz band is investigated. The effects of line-of-sight obstruction as well as antenna pointing deviation on the power link budget are experimentally studied in a typical laboratory environment. The results are contrasted with those obtained with alternative antenna configurations  相似文献   
9.

Background

Several studies demonstrated an association of homocysteine plasma levels and the plasma lipoprotein profile. This cross-sectional pilot study aimed at analyzing whether blood levels of the two important cofactors of homocysteine metabolism, folate and vitamin B12, coincide with the lipoprotein profile.

Methods

In a retrospective single center approach, we analyzed the laboratory database (2003-2006) of the University Hospital Bonn, Germany, including 1743 individuals, in whom vitamin B12, folate and at least one lipoprotein parameter had been determined by linear multilogistic regression.

Results

Higher folate serum levels were associated with lower serum levels of low density lipoprotein cholesterol (LDL-C; Beta = -0.164; p < 0.001), higher levels of high density lipoprotein cholesterol (HDL-C; Beta = 0.094; p = 0.021 for trend) and a lower LDL-C-C/HDL-C-ratio (Beta = -0.210; p < 0.001). Using ANOVA, we additionally compared the individuals of the highest with those of the lowest quartile of folate. Individuals of the highest folate quartile had higher levels of HDL-C (1.42 ± 0.44 mmol/l vs. 1.26 ± 0.47 mmol/l; p = 0.005), lower levels of LDL-C (3.21 ± 1.04 mmol/l vs. 3.67 ± 1.10 mmol/l; p = 0.001) and a lower LDL-C/HDL-C- ratio (2.47 ± 1.18 vs. 3.77 ± 5.29; p = 0.002). Vitamin B12 was not associated with the lipoprotein profile.

Conclusion

In our study sample, high folate levels were associated with a favorable lipoprotein profile. A reconfirmation of these results in a different study population with a well defined status of health, diet and medication is warranted.  相似文献   
10.
Indirect measures have been used for the assessment of food preferences. These measures are indirect in the sense that the researcher does not ask a participant directly for his food preference, but derives his preference from a behavior. Typically, the affective priming paradigm and the Implicit Association Test have been used. The relevant processes in these paradigms are relatively automatic. One of the advantages of these paradigms is that responses are less likely to be influenced by socially desirable response tendencies and do not rely on the participant’s introspection. This paper provides an overview of research about relatively automatic associations with food in general and specifically for anorexia nervosa patients, dieters, and obese people. Multiple studies suggest that these paradigms can uncover food likes and dislikes. In most studies, no differences in food preferences were found between obese and lean people, or between restrained and unrestrained eaters. Possibly there simply are no group differences in automatic food associations. Alternatively, the employed indirect measures are not sensitive enough to detect truly existent differences. Interestingly, it was found that anorexia nervosa patients displayed a reduced sensitivity to the palatability of foods. Another interesting finding is that the presence of an immediate food related context influenced the automatic food associations. For now, the use of indirect measures in explaining differences between obese and lean people, and restrained and unrestrained eaters, does not seem a very viable approach. It might be for a clinical disorder such as anorexia nervosa.  相似文献   
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