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151.
152.
Studied acquisition of the alphabetic principle in preliterate children, 3–5 yrs. The dependent variable throughout was a forced-choice between, e.g., "mow" and "sow" as pronunciations for the written word mow after the child had been taught to read the words mat and sat. Reliable performance on this transfer task was only achieved by children who (a) understood two aspects of phonological organization—phonemic segmentation of the speech items and the identity of their initial segments, and (b) had learned graphic symbols for the sounds "m" and "s." Most children who demonstrated alphabetic insight with symbols in word-initial position were also successful at transfer when the symbols were word-final. Thus, phonemic awareness and grapheme-phoneme knowledge were needed in combination for acquisition of the alphabetic principle, and, once gained, alphabetic insight proved relatively robust. Implications for reading acquisition are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
153.
G. Byrne 《CIRP Annals》2007,56(1):89-92
Two piezo electric force sensor rings were developed and integrated into a direct driven motor spindle for online process monitoring of machining processes. Experimental results are presented which demonstrate the performance of the integrated force sensor during drilling operations. Performance comparisons are made between the integrated force sensors and traditional monitoring sensors such as motor power and acoustic emission. The non cutting influences such as spindle dynamic loading contained in the integrated sensor signals are identified. The potential application of the integrated force sensors for process monitoring encompassing tool condition monitoring, spindle condition monitoring and collision detection is demonstrated.  相似文献   
154.
Detergents are an absolute requirement for studying the structure of membrane proteins. However, many conventional detergents fail to stabilise denaturation‐sensitive membrane proteins, such as eukaryotic proteins and membrane protein complexes. New amphipathic agents with enhanced efficacy in stabilising membrane proteins will be helpful in overcoming the barriers to studying membrane protein structures. We have prepared a number of deoxycholate‐based amphiphiles with carbohydrate head groups, designated deoxycholate‐based glycosides (DCGs). These DCGs are the hydrophilic variants of previously reported deoxycholate‐based N‐oxides (DCAOs). Membrane proteins in these agents, particularly the branched diglucoside‐bearing amphiphiles DCG‐1 and DCG‐2, displayed favourable behaviour compared to previously reported parent compounds (DCAOs) and conventional detergents (LDAO and DDM). Given their excellent properties, these agents should have significant potential for membrane protein studies.  相似文献   
155.
Dissolved organic matter (DOM) can play a key role in many environmental processes, including carbon cycling, nutrient transport and the fates of contaminants and of agrochemicals. Hydrophobic acids (Ho), the major components of the DOM, were recovered from the drainage waters from well-drained (WDS) and poorly-drained (PDS) Irish grassland soils in lysimeters, amended with N fertiliser (F) and with bovine urine (U) and were studied using 1D and 2D solution-state Nuclear Magnetic Resonance (NMR) spectroscopy. The Diffusion Edited (DE) 1H NMR spectra indicated that the Ho consisted largely of larger molecules, or of molecules that formed rigid aggregates, and the 1D and the 2D (Heteronuclear Multiple Quantum Coherence - HMQC, the Total Correlation Spectroscopy - TOCSY, and the Nuclear Overhauser Effect - NOESY) spectra indicated that the samples were composed of lignin residues, carbohydrates, protein/peptides, and aliphatic components derived from plant waxes/cuticular materials and from microbial lipids. The F amendments increased the concentrations of Ho in the waters by 1.5 and 2.5 times those in the controls in the cases of WDS and PDS, respectively. The lignin-derived components were increased by 50% and 300% in the cases of the Ho from the WDS and PDS, respectively. Applications of F + U decreased the losses of Ho, (compared to the F amendments alone) and very significantly decreased those of the lignin-derived materials, indicating that enhanced microbial activity from U gave rise to enhanced metabolism of the Ho components, and especially of lignin. In contrast the less biodegradable aliphatic components containing cuticular materials increased as the result of applications of F + U. This study helps our understanding of how management practices influence the movement of C between terrestrial and aquatic environments.  相似文献   
156.
Nasr A  Bruen M  Jordan P  Moles R  Kiely G  Byrne P 《Water research》2007,41(5):1065-1073
Recent extensive water quality surveys in Ireland revealed that diffuse phosphorus (P) pollution originating from agricultural land and transported by runoff and subsurface flows is the primary cause of the deterioration of surface water quality. P transport from land to water can be described by mathematical models that vary in modelling approach, complexity and scale (plot, field and catchment). Here, three mathematical models (soil water and analysis tools (SWAT), hydrological simulation program-FORTRAN (HSPF) and système hydrologique Européen TRANsport (SHETRAN)/grid oriented phosphorus component (GOPC)) of diffuse P pollution have been tested in three Irish catchments to explore their suitability in Irish conditions for future use in implementing the European Water Framework Directive. After calibrating the models, their daily flows and total phosphorus (TP) exports are compared and assessed. The HSPF model was the best at simulating the mean daily discharge while SWAT gave the best calibration results for daily TP loads. Annual TP exports for the three models and for two empirical models were compared with measured data. No single model is consistently better in estimating the annual TP export for all three catchments.  相似文献   
157.
Two independent sensory profiles were carried out to evaluate warmed-over flavour (WOF) development in cooked, chill-stored and reheated pork patties. The patties were derived from the Musculus semimembranosus of animals subjected to different pre-slaughter stress treatments. All patties were stored in oxygen permeable bags at 4°C for 0, 1, 2, 3 and 5 days to facilitate WOF development. In addition, thiobarbituric acid reactive substances (TBARS), conjugated dienes, pH, water content, total lipids and the fatty acid compositions of phosphatidyl choline (PC), phosphatidyl ethanolamine (PE) and total lipids, were measured in the cooked meat patties. A data analytical strategy involving Analysis of Variance-Partial Least Squares Regression (ANOVA-PLSR), to determine relationships between the design variables (WOF and pre-slaughter stress) and the sensory-chemical data, and PLSR to elucidate predictive links between the sensory and chemical data was utilised. WOF was found to involve the development of lipid oxidation derived nuance off-flavour and odour notes, e.g. rancid-like flavour and linseed oil-like odour, in association with a concurrent decrease in cooked pork meat-like flavour. The reduction in "meatiness", over the initial days, 0-2 of WOF development was attributed to the degradation of both, unstable sulfur-containing amino acids in meat proteins and sulfur-containing "meaty" aroma compounds. Whereas, at the later days, 3-5 of WOF development the "meaty" loss was ascribed to perceptual masking by lipid oxidation products. TBARS and conjugated dienes were found to be significant (P<0.05) predictors of the sensory terms related to the lipid oxidation aspect of WOF. Whilst the polyunsaturated fatty acid (PUFAs) contents of PE, PC and the total lipids were found to decrease with WOF development, reflecting their loss in lipid oxidation reactions. The sensory variation related to pre-slaughter stress appeared to be distinct from WOF variation and was described by a sour to sweet taste continuum. However, interactions were noted that indicated increasing pre-slaughter stress resulted in a decreased sensory perception of WOF. Moreover, pH and water content were found to significantly (P<0.05) predict the sensory effects resulting from pre-slaughter stress.  相似文献   
158.
ABSTRACT: BACKGROUND: Food Frequency Questionnaires (FFQs) are commonly used in epidemiologic studies to assess long-term nutritional exposure. Because of wide variations in dietary habits in different countries, a FFQ must be developed to suit the specific population. Sri Lanka is undergoing nutritional transition and diet-related chronic diseases are emerging as an important health problem. Currently, no FFQ has been developed for Sri Lankan adults. In this study, we developed a FFQ to assess the regular dietary intake of Sri Lankan adults. METHODS: A nationally representative sample of 600 adults was selected by a multi-stage random cluster sampling technique and dietary intake was assessed by random 24-h dietary recall. Nutrient analysis of the FFQ required the selection of foods, development of recipes and application of these to cooked foods to develop a nutrient database. We constructed a comprehensive food list with the units of measurement. A stepwise regression method was used to identify foods contributing to a cumulative 90% of variance to total energy and macronutrients. In addition, a series of photographs were included. RESULTS: We obtained dietary data from 482 participants and 312 different food items were recorded. Nutritionists grouped similar food items which resulted in a total of 178 items. After performing step-wise multiple regression, 93 foods explained 90% of the variance for total energy intake, carbohydrates, protein, total fat and dietary fibre. Finally, 90 food items and 12 photographs were selected. CONCLUSION: We developed a FFQ and the related nutrient composition database for Sri Lankan adults. Culturally specific dietary tools are central to capturing the role of diet in risk for chronic disease in Sri Lanka. The next step will involve the verification of FFQ reproducibility and validity.  相似文献   
159.
Parents' anxiety about their children's anesthesia may adversely affect the children's outcomes and compromise the quality of informed consent. Studies of these issues have been limited by the lack of validated measures of parental anxiety and knowledge surrounding anesthesia. In the present study, we evaluated psychometric properties of the Amsterdam Preoperative Anxiety and Information Scale (APAIS) and the Standard Anesthesia Learning Test (SALT) among 85 parents who participated in an evaluation of the effects of a videotape about pediatric anesthesia. The results supported the internal consistency, test-retest reliability, and concurrent validity of both instruments and documented the equivalence of two forms of the SALT. Factor analysis supported the previously demonstrated factor structure of the APAIS, further confirming its construct validity. We conclude that the APAIS and SALT are reliable and valid measures of parental anxiety and knowledge of pediatric anesthesia that can be used for clinical and research purposes. Implications: This study verified the reliability and validity of two questionnaires for measuring parents' knowledge and anxiety about pediatric anesthesia. These questionnaires can be used in further research on factors affecting parental anxiety and knowledge before their children's surgery.  相似文献   
160.
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