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351.
We conducted a national survey of antimicrobial resistance in human clinical isolates of Salmonella between July 1, 1994, and June 30, 1995. Every tenth nontyphoidal Salmonella isolate received at state public health laboratories in the United States during this period was tested for resistance to 12 antimicrobial agents, including two quinolones, nalidixic acid, and ciprofloxacin. Emerging quinolone resistance was detected; of 4,008 isolates tested, 21 (0.5%) were resistant to nalidixic acid, and one (0.02%) was resistant to ciprofloxacin. Continued surveillance for quinolone-resistant Salmonella is necessary, particularly after the recent approval of a fluoroquinolone for use in animals intended for food in the United States.  相似文献   
352.
A one-year prospective study comparing Section 136 patients (39) and the severe Section 2 or 4 patients (29) of the Mental Health Act 1983 in a hospital with inner London catchment areas. The assessments were clinical, nurses' ratings and socio-demographic. The results showed that clinical and nursing ratings did not differentiate the two groups. Most social/demographic data showed similar trends with both groups being disadvantaged but Section 136 patients slightly more so. The differences were smaller than anticipated, suggesting a recent shift of patients admitted under Section 2 or 4 towards a more socially disadvantaged position. In conclusion, police did not overuse Section 136. Our comparison suggests: (a) police may underuse Section 136, and (b) Section 136 acts as a valuable 'back-up' for those patients who would otherwise fail to benefit from the Mental Health Act.  相似文献   
353.
While 4-benzylidene-3-methyl-5-oxopyrazoline 1 and pyrazole blue 2 with GRIGNARD reagents gave 1,4-addition, rubazoic acid 3 gave 1, 2-addition on both sides with ethylmagnesium bromide.  相似文献   
354.
Assuring medical images protection and robustness is a compulsory necessity nowadays. In this paper, a novel technique is proposed that fuses the wavelet-induced multi-resolution decomposition of the Discrete Wavelet Transform (DWT) with the energy compaction of the Discrete Wavelet Transform (DCT). The multi-level Encryption-based Hybrid Fusion Technique (EbhFT) aims to achieve great advances in terms of imperceptibility and security of medical images. A DWT disintegrated sub-band of a cover image is reformed simultaneously using the DCT transform. Afterwards, a 64-bit hex key is employed to encrypt the host image as well as participate in the second key creation process to encode the watermark. Lastly, a PN-sequence key is formed along with a supplementary key in the third layer of the EbHFT. Thus, the watermarked image is generated by enclosing both keys into DWT and DCT coefficients. The fusions ability of the proposed EbHFT technique makes the best use of the distinct privileges of using both DWT and DCT methods. In order to validate the proposed technique, a standard dataset of medical images is used. Simulation results show higher performance of the visual quality (i.e., 57.65) for the watermarked forms of all types of medical images. In addition, EbHFT robustness outperforms an existing scheme tested for the same dataset in terms of Normalized Correlation (NC). Finally, extra protection for digital images from against illegal replicating and unapproved tampering using the proposed technique.  相似文献   
355.
356.
Multidimensional Systems and Signal Processing - Electroencephalogram (EEG) signals can be used by a proficient neurologist to detect the presence of seizure activity inside the brain. Automated...  相似文献   
357.
Pork identification in raw meat using real-time polymerase chain reaction (PCR) was developed. Total DNA from meat samples were successfully extracted and found to be of high quality and produced clear PCR products. Porcine-specific molecular beacon probe and primers that amplifies 119 bp of the cytochrome b gene fragment of swine (Sus scrofa domestica) was used. Analysis of data showed that the C q (quantification cycle) from 10 ng/μl porcine DNA is (18.70 ± 0.12 to 19.08 ± 0.06). Meanwhile, the other samples exhibited negative result, which confirmed the specificity of the primers. The method also showed that the limit of detection of pork was 0.0001 ng. Based on the regression analysis of the standard curve, the 96% efficiency of real-time PCR was achieved with high correlation coefficient (r 2 = 0.9989). Sensitivity of the assay in discriminating pork as low as 0.1% (w/w) pork in pork–beef mixtures was also obtained. Reproducibility of the assay was successfully validated by applying sample and experimental replicates in every assay being conducted. Thus, this methodology could serve as a fast and sensitive method for detection of pork for meat species verification.  相似文献   
358.
Polyphenols have become a subject of intense research because of their perceived beneficial effects on health due to their anticarcinogenic, antiatherogenic, anti-inflammatory, and antimicrobial activities. It is well known that olives and their derivatives are rich in phenolic substances with pharmaceutical properties, some of which exert important antioxidant effects. The characterization and quantification of their polyphenol composition is one of the first steps to be taken in any evaluation of the putative contribution of the olive to human health. This review is concerned with polyphenols in Tunisian olive (Olea europaea L.) products (fruit and oil) and some by-products (leaves and olive-mill wastewater) with an emphasis on the analytical methods used, as well as the biological activities described in recent years.  相似文献   
359.
Abstract: Chemical analysis was carried out on lantana (Lantana camara) and sweet pepper (Capsicum annuum L.) seeds and nabak (Zizyphus spina‐christi) seed kernels. The proximate analysis (on dry weight basis) of sweet pepper seeds, lantana seeds, and nabak seed kernels showed the following composition: moisture 70.95%, 17.27%, and 4.22%; ash 4.88%, 1.81%, and 3.51%; fat 19.57%, 11.0%, and 30.19%; crude protein 19.28%, 6.3%, and 38.2%; and carbohydrate 56.3%, 80.9%, and 28.1%, respectively. For minerals, potassium was the most abundant element, followed by phosphorus and sodium. Also, zinc, iron, copper, and manganese were detected. Analysis of amino acids revealed that the first limiting amino acid was valine, for both lantana and sweet pepper seeds, but it was threonine for nabak seed kernels. Antinutritional compounds, including, phytic acid, trypsin inhibitor, and tannins, were detected in all seeds. Results of fatty acid compositions showed that the major fatty acid was oleic acid in both lantana (48.73%) and nabak oils (53.25%), but it was linoleic acid in sweet pepper oil (71.55%). Moreover, the degree of unsaturation of these oils was close to that of common vegetable oils. In all oils, there was absorbance in the ultraviolet (UV)‐B and UV‐C ranges with potential for use as broad spectrum UV protectants. It can be inferred that the seeds investigated are good sources of crude fat, crude protein, ash, carbohydrate, and some minerals. Furthermore, the oil extracts could be useful as edible oils and for industrial applications. Practical Application: The nutritional composition of the investigated seeds suggested that they could be used to meet part of the nutritional requirements of animal feeds. Also, they could be regarded as good sources of food ingredients and as new sources of edible oils.  相似文献   
360.
BACKGROUND: The effects of salt on the essential oil yield and fatty acid composition of aerial parts of two marjoram varieties were investigated. Plants with 6 leaves were treated with NaCl (75mM). RESULTS: Salt treatment led to a reduction in aerial part growth. Salinity increased the fatty acid content more significantly in Tunisian variety (TV) than in Canadian variety (CV). CV showed an increase in double‐bond index (DBI) and a decrease in malondialdehyde content under salt stress, while the opposite was observed in TV. The DBI was mainly affected by a strong reduction in oleic and linoleic acids in TV, whereas a strong stimulation of linoleic acid in CV was observed. Salt decreased and increased the essential oil yield in TV and CV respectively. The main constituents of the essential oil of TV were trans‐hydrate sabinene and terpinen‐4‐ol, which showed a significant decrease under salt stress. In contrast, the main constituents of the essential oil of CV were sabinene and trans‐hydrate sabinene, which showed a significant decrease and increase respectively under salt stress. CONCLUSION: Marjoram oil is a rich source of many compounds such as essential oils and fatty acids, but the distribution of these compounds differed significantly between the two varieties studied. Copyright © 2011 Society of Chemical Industry  相似文献   
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