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991.
Aurora Marco Manuel M. Juarez Nigel Brunton Przemyslaw D. Wasilewski Brendan Lynch Sung-Sil Moon Declan J. Troy Anne M. Mullen 《Food chemistry》2009
Approaches for improving the profile of functional unsaturated fatty acids in pork products include dietary supplementation of pigs with functional oils. Little information is available to indicate the benefit of this approach in a processed and cooked pork product such as breakfast sausages. Therefore, the aim of the present study is to examine the fatty acid profile and oxidation level in cooked pork sausages, produced following dietary supplementation with CLA compared to sunflower oil (SFO). Fat and moisture percentages, total fatty acid profiles and TBARS were analysed. Fatty acid profiles were altered in the sausages following all treatments. While a stronger effect was seen for CLA treatments, addition of SFO in the diet also resulted in linear increases of CLA in the sausages. CLA supplementation resulted in increased saturated fatty acid content; however, all treatments were within the recommended polyunsaturated/saturated fatty acid ratio of above 0.4. Improved oxidative stability was observed in sausages from CLA supplemented diets. 相似文献
992.
Marcus Schmidt Emanuele Zannini Kieran M. Lynch 《Critical reviews in food science and nutrition》2019,59(21):3395-3419
AbstractEconomic losses due to post-harvest fungal spoilage and mycotoxin contamination of cereal crops is a frequently encountered issue. Typically, chemical preservatives are used to reduce the initial microbial load and the environmental conditions during storage are controlled to prevent microbial growth. However, in recent years the consumers’ desire for more naturally produced foods containing less chemical preservatives has grown increasingly stronger. This article reviews the latest advances in terms of novel approaches for chemical decontamination, namely application cold atmospheric pressure plasma and electrolyzed water, and their suitability for preservation of stored cereal crops. In addition, the alternative use of bio-preservatives, such as starter cultures or purified antimicrobial compounds, to prevent the growth of spoilage organisms or remove in-field accumulated mycotoxins is evaluated. All treatments assessed here show potential for inhibition of microbial spoilage. However, each method encounters draw-backs, making industrial application difficult. Even under optimized processing conditions, it is unlikely that one single treatment can reduce the natural microbial load sufficiently. It is evident that future research needs to examine the combined application of several treatments to exploit their synergistic properties. This would enable sufficient reduction in the microbial load and ensure microbiological safety of cereal crops during long-term storage. 相似文献
993.
Alejandro Baró Pérez Conor Lynch Adrián L. Ferrer Hernández Israel Borrajero Montejo Alfredo Roque Rodríguez 《国际可持续能源杂志》2019,38(6):511-525
The performance of the Weather Research and Forecasting (WRF) model, coupled with a bank of eight Kalman Filters (KFB) as a post-processor toolbox for the three hourly average WRF wind speed forecasts, is investigated and compared to the output of the WRF model alone. Two model set-ups, WRF and WRF+KFB, have been tested for the period January to December 2008 on nine locations corresponding to gradient wind towers of the Cuban Eolic program. Tests demonstrated that the KFB post-processing technique, using a third-order polynomial, combined with a four-point a priori moving window averager for covariance matrix computation, was the best configuration for improving the WRF grid model day-ahead wind speed forecast output. The WRF+KFB approach investigated has been shown to adapt to changing wind speed patterns and to offer improved wind speed forecasts for each location considered, whilst only requiring a limited data set for training purposes. 相似文献
994.
We present a new method of reducing the error in predicted wind speed, thus enabling better management of wind energy facilities. A numerical weather prediction model, COSMO, was used to produce 48 h forecast data every day in 2008 at horizontal resolutions of 10 and 3 km. A new adaptive statistical method was applied to the model output to improve the forecast skill. The method applied corrective weights to a set of forecasts generated using several post‐processing methods. The weights were calculated based on the recent skill of the different forecasts. The resulting forecast data were compared with observed data, and skill scores were calculated to allow comparison between different post‐processing methods. The total root mean square error performance of the composite forecast is superior to that of any of the individual methods. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
995.
McKay James R.; Lynch Kevin G.; Coviello Donna; Morrison Rebecca; Cary Mark S.; Skalina Lauren; Plebani Jennifer 《Canadian Metallurgical Quarterly》2010,78(1):111
Objective: The effects of cognitive–behavioral relapse prevention (RP), contingency management (CM), and their combination (CM + RP) were evaluated in a randomized trial with 100 cocaine-dependent patients (58% female, 89% African American) who were engaged in treatment for at least 2 weeks and had an average of 44 days of abstinence at baseline. Method: The participants were from intensive outpatient programs, which provide 10 hr per week of group counseling. The CM protocol provided gift certificates (maximum value $1,150; mean received = $740) for cocaine-free urines over 12 weeks on an escalating reinforcement schedule, and weekly individual RP sessions were offered for up to 20 weeks. Average number of RP sessions attended was 3 in RP and 13 in CM + RP. Results: Generalizing estimation equation analyses over 18 months postrandomization showed significant effects for CM (but not RP) on urine toxicology and self-reported cocaine use (p = .05), with no significant CM × RP interactions. Secondary analyses indicated CM + RP produced better cocaine urine toxicology outcomes at 6 months than treatment as usual, odds ratio [OR] = 3.96 (1.33, 11.80), p p p p p = .06, and 9 months, OR = 2.93 (0.94, 9.10), p = .06. Differences between the conditions were not significant after 9 months. Conclusions: These results suggest CM can improve outcomes in cocaine-dependent patients in intensive outpatient programs who have achieved initial engagement, particularly when it is combined with RP. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
Addition of grape seed extract and bearberry to porcine diets: Influence on quality attributes of raw and cooked pork 总被引:1,自引:0,他引:1
The effect of supplementation of pig diets with grape seed extract (GSE) (100, 300, 700 mg/kg feed) and bearberry (BB) (100, 300, 700 mg/kg feed) for 56 days pre-slaughter, on the oxidative stability and quality of raw and cooked M. longissimus dorsi (LD) was examined. Susceptibility of porcine liver, kidney and heart tissue homogenates to iron-induced (1 mM FeSO4) lipid oxidation was also investigated. In raw LD steaks, stored in modified atmosphere packs (75% O2:25% CO2) (MAP) for up to 16 days at 4 °C, surface lightness (CIE ‘L’ value), redness (CIE ‘a’ value), lipid stability (TBARS, mg MDA (malondialdehyde)/kg muscle) and pH were not significantly affected by supplemental GSE or BB. Similarly, the oxidative stability and sensory properties of cooked LD steaks, stored in MAP (70% N2:30% CO2), for up to 28 days at 4 °C, were not enhanced by dietary GSE or BB. Iron-induced lipid oxidation increased in liver, kidney and heart tissue homogenates over the 24 h storage period and susceptibility to oxidation followed the order: liver > heart > kidney. Dietary GSE or BB did not significantly reduce lipid oxidation in tissue homogenates. Potential reasons for the lack of efficacy of supplemental GSE and BB on pork quality were explored. 相似文献
997.
A Parallel Simulated Annealing Architecture for Model Updating in Wireless Sensor Networks 总被引:1,自引:0,他引:1
In recent years, wireless sensing technologies have provided a much sought-after alternative to expensive cabled monitoring systems. Wireless sensing networks forego the high data transfer rates associated with cabled sensors in exchange for low-cost and low-power communication between a large number of sensing devices, each of which features embedded data processing capabilities. As such, a new paradigm in large-scale data processing has emerged; one where communication bandwidth is somewhat limited but distributed data processing centers are abundant. By taking advantage of this grid of computational resources, data processing tasks once performed independently by a central processing unit can now be parallelized, automated, and carried out within a wireless sensor network. By utilizing the intelligent organization and self-healing properties of many wireless networks, an extremely scalable multiprocessor computational framework can be developed to perform advanced engineering analyses. In this study, a novel parallelization of the simulated annealing stochastic search algorithm is presented and used to update structural models by comparing model predictions to experimental results. The resulting distributed model updating algorithm is validated within a network of wireless sensors by identifying the mass, stiffness, and damping properties of a three-story steel structure subjected to seismic base motion. 相似文献
998.
Powers Alice Schade; Hogue Phillip; Lynch Christian; Gattuso Brian; Lissek Shmuel; Nayal Christine 《Canadian Metallurgical Quarterly》2009,123(4):804
Turtles were run on a negative patterning task involving 2 positive elements, a key with white stripes on a black background, and a solid red key, and a compound stimulus combining the 2 elements, white stripes on a red background. Injections of scopolamine, methylscopolamine, or saline were started at the same time that the compound stimulus was introduced, after the animals had been autoshaped to press the key for each of the elements. Scopolamine disrupted the learning of negative patterning, but methylscopolamine had no effect. In contrast, learning of a simple discrimination between the elements was not affected by scopolamine. These results show that muscarinic cholinergic receptors are involved in the learning of negative patterning in turtles. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Decay-accelerating factor (DAF) is a glycosylphosphatidylinositol (GPI)-anchored membrane protein that inhibits both the classical and the alternative pathways of complement activation. DAF has been studied extensively in humans under two clinical settings: when absent from the erythrocytes of paroxysmal nocturnal hemoglobinuria (PNH) patients, who suffer from complement-mediated hemolytic anemia, and in transgenic pigs expressing human DAF, which have been developed to help overcome complement-mediated hyperacute rejection in xenotransplantation. Nevertheless, the exact role of DAF in regulating complement activation in vivo on the cell surface and the species specificity of this molecule remain to be fully characterized. To address these issues, we have used gene targeting to produce mice lacking GPI-anchored DAF. We found that erythrocytes from mice deficient in GPI-anchored DAF showed no increase in spontaneous complement activation in vivo but exhibited impaired regulation of zymosan-initiated bystander and antibody-triggered classical pathway complement activation in vitro, resulting in enhanced complement deposition. Despite a high level of C3 fixation, no homologous hemolysis occurred. It is noteworthy that GPI-linked DAF knockout erythrocytes, when tested with human and guinea pig sera, were more susceptible to heterologous complement lysis than were normal erythrocytes. These results suggest that DAF is capable of regulating homologous as well as heterologous complement activation via the alternative or the classical pathway. They also indicate that DAF deficiency alone is not sufficient to cause homologous hemolysis. In contrast, when the assembly of the membrane-attack complex is not properly regulated, as in the case of heterologous complement activation or in PNH patients, impaired erythrocyte DAF activity and enhanced C3 deposition could lead to increased hemolytic reaction. 相似文献
1000.
SG McInroy CD Campbell KE Haukka DW Odee JI Sprent WJ Wang JP Young JM Sutherland 《Canadian Metallurgical Quarterly》1999,170(1):111-117
Blood was collected from two Sahelian goats, experimentally infected with either a drug-sensitive cloned population of Trypanosoma congolense (IL 1180) or a multiple drug-resistant T. congolense stock (Samorogouan/89/CRTA/267) and incubated at 37 degrees C for 30 min and 12 h, respectively, in the presence of different drug concentrations (0.5, 1.0, 10.0 and 100.0 microg/ml blood) of diminazene aceturate or isometamidium chloride. After that, the trypanosome/blood/drug suspensions were offered to tsetse flies (2100 teneral Glossina morsitans submorsitans) through an in vitro feeding system, using a silicone membrane. All tsetse flies were dissected and examined for the presence of trypanosomes in labrum, hypopharynx and midgut 20 days after their infective blood-meals. Infectivity of the drug-sensitive cloned population was already completely abolished after incubation with 0.5 microg/ml of both drugs; however, 13.6-42.2% of tsetse having been fed on untreated blood had developed an infection. In contrast, no significant differences were observed in the infection rates between the experimental groups and their control groups when fed on blood infected with the multiple drug-resistant stock after incubation for 30 min with up to 10 microg/ml of diminazene or isometamidium. In consequence, tsetse appear to be a useful tool in the assessment of drug susceptibility of typanosome populations. 相似文献