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241.
French fries made from coloured-fleshed potatoes may be interesting alternative to the traditional snacks for consumers. However, potatoes contain glycoalkaloids (TGA), so potato tubers and obtained fried snacks should be subjected to comprehensive examination. The aim of this study was to determine the effect of different stages of French fries processing on the content of TGA (α-solanine and α-chaconine) in the red- and blue-fleshed potatoes, in semi-products and ready-to-eat products. It was stated that during the processing of French fries prepared from coloured-flesh potato varieties significantly decreased the content of TGA (α-solanine and α-chaconine) in the samples obtained at different stages of the process compared to the raw material. Potatoes with blue-fleshed of Vitelotte variety and red-fleshed of Highland Burgundy Red variety can be used to French fries processing due to their low content of TGA (in unpeeled and peeled potatoes). However, Blue Congo variety with blue-fleshed should not be applied to French fries processing, because of high TGA content in raw material and first of all in peeled potatoes flesh. The peeling process of coloured-fleshed potatoes decreased in TGA content on average by about 50 %, cutting process on average by about 53 %, whereas blanching on average by about 58 % compared with the raw material. The highest decrease in TGA content was caused by frying process. The mean values were about 97.5 % in ready-to-eat French fries. In French fries after I and II steps of frying, the ratio α-solanine to α-chaconine was lower (1.0:2.0) than in unpeeled potatoes (1.0:2.3).  相似文献   
242.
This paper presents an image morphing algorithm for quantitative evaluation methodology of terahertz (THz) images of excised breast cancer tumors. Most current studies on the assessment of THz imaging rely on qualitative evaluation, and there is no established benchmark or procedure to quantify the THz imaging performance. The proposed morphing algorithm provides a tool to quantitatively align the THz image with the histopathology image. Freshly excised xenograft murine breast cancer tumors are imaged using the pulsed THz imaging and spectroscopy system in the reflection mode. Upon fixing the tumor tissue in formalin and embedding in paraffin, a formalin-fixed paraffin-embedded (FFPE) tissue block is produced. A thin slice of the block is prepared for the pathology image while another THz reflection image is produced directly from the block. We developed an algorithm of mesh morphing using homography mapping of the histopathology image to adjust the alignment, shape, and resolution to match the external contour of the tissue in the THz image. Unlike conventional image morphing algorithms that rely on internal features of the source and target images, only the external contour of the tissue is used to avoid bias. Unsupervised Bayesian learning algorithm is applied to THz images to classify the tissue regions of cancer, fat, and muscles present in xenograft breast tumors. The results demonstrate that the proposed mesh morphing algorithm can provide more effective and accurate evaluation of THz imaging compared with existing algorithms. The results also showed that while THz images of FFPE tissue are highly in agreement with pathology images, challenges remain in assessing THz imaging of fresh tissue.  相似文献   
243.
In this paper, we present a discrete time Markov chain based analytical framework for the study of Direct-Sequence Code-Division-Multiple-Access (DS-CDMA) with slotted ALOHA random access protocols (DS-CDMA-S-ALOHA) for packet Personal Communications Networks (PCNs). It incorporates both the random access and the random errors associated with DS-CDMA-S-ALOHA protocols into a unified framework. The key feature is that it distinguishes between the two stages in the transmission process, namely the access stage and the reception stage, which characterize the random access and the random errors associated with DS-CDMA-S-ALOHA protocols respectively. Two DS-CDMA-S-ALOHA protocols are presented and analyzed. The performance of the protocols and the effects of the design parameters, namely the packet retransmission probability and the forward error correction code rate of the Bose-Chaudhuri-Hocquenghem (BCH) block codes are evaluated numerically and compared with a bandwidth equivalent conventional multi-channel slotted ALOHA system. The results show that, by proper design, the DS-CDMA-S-ALOHA protocols can double the throughput with respect to that of a bandwidth equivalent conventional multi-channel slotted ALOHA system.  相似文献   
244.
A quartz dilatometer with capacitance transducer has been designed. The electrical circuitry and operational technique are described. The dilatometer design and measurement circuitry make it possible to detect an increase of 6.10?5 mm in specimen length.  相似文献   
245.
Chlorine dioxide in unbuffered aqueous solution at pH 9 and 25°C decomposes to chlorate, chlorite, chloride and oxygen by coupled slow and rapid reactions. The initiation of the second rapid decomposition depends on the initial chlorine dioxide concentration and ionic strength of the solution. Chloride ion has a catalytic and inhibiting effect, changing the product distribution to a 1:1 molar ratio of chlorate and chlorite, thus increasing the oxidizing potential of chlorine dioxide. In buffered solutions at pH 8.8 the reaction is pseudo-second order, yielding chlorate and chlorite as products.  相似文献   
246.
An attempt of PCS was performed for the first time in Japan. Eighteen hundred twenty-six preschool and school children were examined and the result was compared with other studies (physician's auscultation and PCG). The time requirement for a single child is approximately 1.5 min. in primary school. It took longer time in kindergarten. The heart murmur detection rate is high and the sensitivity is fairly good, although it is not so good as well-trained physician's heart murmur detection rate. PCS is not perfect, but is fairly good tool for screening. It can be used only by technician. PCS may be able to save the physician's time.  相似文献   
247.
Acrylamide monomer (AAm) was grafted onto poly(vinyl chloride) (PVC) films using γ‐radiation to produce high performance functional membranes which can be employed as ion‐exchangers. The preparation and characterization of the synthetic membranes are investigated. To elucidate their possible applications, some selected properties have been studied. In addition, thermal properties have been studied using thermogravimetric analysis and differential scanning calorimetry; X‐ray diffraction has been used to determine changes in polymer morphology. The selectivity of such membranes towards different radionuclides has also been investigated. On the basis of these investigations, the applicability of the prepared membranes is determined and discussed. The prepared PVC‐g‐PAAm has a great tendency to remove 60Co from a radioactive liquid waste containing both 60Co and 137Cs. © 2002 Society of Chemical Industry  相似文献   
248.
Various amino acids and the yeast extract, in amounts of 0.1%(w/v), were separately tested for their influence on the analytical parameters of lactic acid fermentation of cabbage juice with Bifidobacterium animalis subsp. lactis BB-12. Compared with the control, cysteine supplementation led to a decrease of the time to reach pH 5.0 of 6 times and an increase of lactic acid productivity of 1.22 times. After 48 h the ascorbic acid content was by 360.73% higher, the fermented cabbage juices being assigned into a distinct group applying both factor analysis (FA) and cluster analysis (CA). Tryptophan contributed to better values for lactic and acetic acid yield, while lysine and yeast extract especially for acetic acid yield. Valine and leucine were not able to improve the fermentation progress, estimated through the analyzed variables. This work would provide some helpful information for the development of various lacto-fermented vegetable juices using probiotic bacteria.  相似文献   
249.
250.
Genaidy AM  Rinder MM  A-Rehim AD 《Ergonomics》2008,51(8):1195-1218
The manufacturing sector in the US is challenged by high health care costs and shortage of qualified workers, which are largely attributed to the degree of fit between the worker and work environment. In this regard, a healthy worker-work environment interface is a necessary and sufficient condition for the containment of health care costs and the retaining/attraction of highly qualified knowledge workers and should be based on the principles of optimum physical, cognitive and emotional health for the workers. In prior research, the Work Compatibility Improvement Framework (WCIF) was introduced as a vehicle to address these issues and was defined as the identification, improvement and maintenance of the well-being characteristics of the workforce and its interaction with the work environment through the application of engineering, medicine, management and human sciences methodologies, technologies and best practices. This paper advances WCIF by examining its applications in manufacturing with regard to the evaluation of working conditions impacting musculoskeletal/stress outcome measures. A study was conducted in a machining department of a bag packaging manufacturer in the Midwest of the United States. The work tasks were planned and executed with regard to the following aims: (1) to compute work compatibility as a function of work demands and energisers; (2) to establish whether the prevalence of musculoskeletal/stress disorders increases with a decrease in the quality of worker-work environment interface in terms of work compatibility level and other work factors such as shift and job category. A major finding is that a 'poor' work environment (a function of all work domains) results in musculoskeletal/stress disorders that are 105% and 67% higher than those for a 'good' work environment. The evening shift exhibited the poorest compatibility followed by the night shift relative to the day shift. Application of the work compatibility approach demonstrated the detection of non-added value work. It is essential to evaluate the various domains of worker-work environment interface to uncover the root causes that tend to sub-optimise the physical/cognitive/emotional health of the workforce. The WCIF was used to uncover the non-value added effort in the work process. These findings will have major implications for developing and implementing customised design interventions with the aim to maximise the benefit and reduce the cost of employees in a manufacturing enterprise. The study findings suggest that the WCIF should be pursued as a potential strategic tool for optimising human performance in an enterprise to create healthy workplaces.  相似文献   
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