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151.
Sven Hoche Daniel Krause Mohamed A. Hussein Thomas Becker 《International Journal of Food Science & Technology》2016,51(3):710-719
In order to implement process analytical technology in beer manufacturing, an ultrasound‐based in‐line sensor was developed which is capable to determine sound velocity and density via the multiple reflection method. Based on a systematic study of the ternary system water–maltose–ethanol, two models were established to estimate the critical process parameters: sugar and ethanol mass fraction. The sound velocity‐based model showed unreasonable high errors although temperature variations and deviations due to dissolved CO2 were corrected. In contrast, the sound velocity–density–temperature model provided an average root mean square error of 0.53%g/g sugar and 0.26%g/g ethanol content for the main fermentation. Method, sensor and model showed the capability to capture the process signature which may be related to product and process quality. 相似文献
152.
Jennifer M.C. Van Os Daniel M. Weary Joao H.C. Costa Maria J. Hötzel Marina A.G. von Keyserlingk 《Journal of dairy science》2019,102(9):8290-8304
Our objective was to evaluate how sampling strategies (i.e., how many cows to sample and which animals to include) used in 4 dairy cattle welfare assessment programs affect the classification of dairy farms relative to thresholds of acceptability for animal-based measures. We predicted that classification performance would improve when more cows were sampled and when selecting from all lactating cows versus when some pens were excluded. On 38 freestall farms, we assessed all 12,375 cows for lameness, injuries on the tarsal (hock) and carpal joints, and body condition score and calculated the farm-level prevalence for each measure. Based on approaches used in the industry, we evaluated 6 sampling strategies generated using formulas with precision (d) of 15, 10, or 5% applied to either a single high-producing pen or all lactating cows; an additional sample was included with d = 10% applied to the entire herd, selecting lactating cows in proportion to their representation in the herd. For each sampling strategy, cow records were selected randomly (in 10,000 replicates) to calculate prevalence. The strategy of assessing all cows in the high-producing pen was also compared. Farms were classified as meeting (below) or failing to meet (above) thresholds of ≤15% moderate lameness; ≤20% moderate carpal or hock injuries; <10, <5, and ≤1% severe lameness; or injuries on the carpus or hock; and <5, <3, <1, or 0% thin cows. For each measure and threshold, we calculated pooled percent agreement, kappa, sensitivity, specificity, and positive and negative predictive value for each sampling strategy using true prevalence as the gold standard for herd classification. Across measures and thresholds, classification performance increased with the number of cows sampled [i.e., when narrower precision values (d = 5 vs. 10 vs. 15%) were used in the sample size calculation]. Because narrower precision values can dramatically increase sample size, assessment programs may need to consider both feasibility and the degree of misclassification they will accept. Applying the formula directly to lactating cows performed better than applying it to the entire herd and then selecting lactating cows in proportion to their representation in the herd. Farm classifications were similar whether cows in the hospital pen were included or excluded from the sample. Selecting all cows from the high-producing pen resulted in classifications similar to when including all lactating cows, suggesting that assessing cows from the high-producing pen may serve as an acceptable proxy for all lactating cows on the farm. 相似文献
153.
The effects of sex, slaughtered age (9 vs. 12 months) and livestock production system (freedom extensive system vs. semi extensive system) of “Galician Mountain” foals breed on the fatty acid composition were studied. The sex and slaughtered age of the animals had no statistical significance in the intramuscular fatty acids. Furthermore, the livestock production system showed differences in the fatty acid profiles from the Longissimus dorsi. The feeding system showed significant differences in PUFA content (P < 0.001) higher in freedom extensive production system that semi extensive system, whereas MUFA content was significantly (P < 0.001) higher in semi extensive system. This major PUFA content in freedom extensive production showed a significant (r = 0.70, P < 0.01) correlation with C18:3n− 3 content and can be attributed to their eaten only pasture until slaughtered. The higher MUFA contents (P < 0.001) observed for semi extensive production system foals were very significant (r = 0.98, p < 0.01) correlated with C18:1cis−9 content and less significant (r = 0.81, P < 0.01) correlated with C16:1cis−9 content. In addition, the data reinforced the evidence that foals from extensive production system on wood pasture have a higher nutritional quality (mainly due to the higher levels of n−3 PUFA) when compared to concentrate-fed foals, as a result of the beneficial effects of grass on meat fatty acid profiles. 相似文献
154.
Andréa G. Antonio Renata S. Moraes Daniel Perrone Lucianne C. Maia Kátia Regina N. Santos Natália L.P. Iório Adriana Farah 《Food chemistry》2010
Coffee beverage has been associated with antibacterial activity against Streptococcus mutans, a cariogenic bacterium. This study aimed at identifying natural compounds in coffee that contribute to such activity and investigate the influence of species, roasting and decaffeination on it. Coffee chemical compounds and aqueous extracts of green and roasted regular and decaffeinated Coffea arabica and Coffea canephora beans were tested. MIC, biofilm inhibition and biofilm reduction results were correlated with the concentration of coffee compounds in the extracts. 5-Caffeoylquinic acid, trigonelline and caffeic acid solutions showed bacteriostatic activity (MIC = 0.8 mg/mL). Lighter and regular extracts showed higher inhibitory activity than darker and decaffeinated extracts, with an inverse correlation between bacterial colony-forming units and roasting degree. Only regular C. canephora extracts showed biofilm formation inhibition. The joint effect of chlorogenic acids, trigonelline and caffeine or other compounds removed by decaffeination seems to be one of the causes for coffee antibacterial activity against S. mutans. 相似文献
155.
The potential food applications of water-in-oil-in-water (W1/O/W2) double emulsions are great, including the encapsulation of flavours or active ingredients. However, the stability of these emulsions restricts their applications in food systems. Sodium caseinate (NaCN)–maltodextrin (Md40 or Md100) conjugates were investigated for their potential to improve the stability of W1/O/W2 double emulsions compared to NaCN. NaCN–Md40 and NaCN–Md100 conjugates were prepared by a Maillard-type reaction by dry heat treatment of mixtures of NaCN–Md40 or NaCN–Md100 at 60 °C and 79% relative humidity for 4 days. Water-in-oil-in-water (W1/O/W2) double emulsions with NaCN, NaCN–Md40 or NaCN–Md100 as outer aqueous phase containing emulsifier were prepared using a two-step emulsification process. General emulsion stability was characterised by determining the droplet size distribution, viscosity characteristics and by confocal microscopy of the W1/O/W2 double emulsions on formation and after their storage under accelerated shelf life testing conditions at 45 °C for up to 7 days. Inner phase encapsulation and stability were characterised by monitoring the level of entrapped Vitamin B12 in the inner aqueous phase on formation of the double emulsions and after storage at 45 °C for up to 7 days. Conjugate stabilized emulsions were more generally stable than NaCN stabilized emulsions. In comparison to NaCN stabilized emulsions, conjugate stabilized emulsions showed improved Vitamin B12 encapsulation efficiency in the inner aqueous phase on emulsion formation and improved encapsulation stability following storage of the emulsions. 相似文献
156.
Danyluk MD Interiano Villeda LO Friedrich LM Schneider KR Etxeberria E 《Journal of food protection》2010,73(12):2276-2280
The survival-growth capacity of Salmonella populations on tomato epidermis labeled by a natural-light labeling system was investigated after persistent fears of such marks serving as possible entryways for the pathogenic organisms, alone and in the presence of Pectobacterium carotovorum subsp. carotovorum, a soft-rot organism. Different treatments involving natural-light labeling, fruit waxing, and a five-strain cocktail of Salmonella were applied to mature green tomato surfaces in different sequences prior to storage at 4, 12, or 25°C. Fruit was sampled every 3 days, and Salmonella was enumerated from all treatments and unlabeled fruit, which served as controls. There were no significant differences between treatments or between treatments and controls throughout. The results indicate that the cuticle and epidermal interruptions caused by natural-light labeling do not facilitate the penetration and colonization of the tomato pericarp. In a separate set of experiments, the capacity of Salmonella to penetrate tomato in the presence of a potential synergism with P. carotovorum subsp. carotovorum was investigated. The addition of P. carotovorum at higher, lower, or equal population densities to Salmonella did not significantly alter the behavior of Salmonella on tomatoes stored at 25°C, regardless of natural-light labeling. The inability of P. carotovorum and Salmonella to colonize natural-light-etched surfaces of tomato fruit indicates that the use of this technology does not adversely compromise the surface of tomatoes. 相似文献
157.
A biofilm reactor was used to investigate kinetic and thermodynamic aspects of the sorption of polycyclic aromatic hydrocarbons (PAH) as model compounds for hydrophobic organic contaminants (HOC) to intact microbial biofilms. Effective diffusion coefficients are in the range of 10(-10) cm2 x s(-1) resulting in equilibration times of more than 3 days for a biofilm of 100 microm thickness. Diffusion in the biofilm was strongly temperature-dependent and increased by a factor of 3 (phenanthrene) to 6 (fluoranthene, pyrene) between 5 and 35 degrees C. Drying and rewetting of the biofilm as well as the inclusion of Ca2+ ions and of humic acids all strengthened the biofilm rigidity and slowed down the diffusion of PAH. The later two factors also influenced the thermodynamics of the process as they supported the partitioning of PAH into the biofilm. Humic acid inclusion from solution into the biofilm illustrates that a microbial biofilm can act as a primer allowing for the buildup of a particulate organic phase from dissolved organic matter. PAH metabolites (3-hydroxy-phenanthrene and 1-hydroxy-2-naphthoic acid) showed lower partition coefficients as compared to their parent compounds and 3-hydroxy-phenanthrene also showed a higher diffusion constant, indicating that these transformation products would be easily released into the water phase upon formation during PAH biodegradation in a biofilm. These results allow the quantification of the influence of environmental conditions on a biofilm's function as a sink or as a diffusion barrier for PAH from aqueous solution, and they indicate the importance of kinetic aspects of this partitioning process. 相似文献
158.
Anne-Marieke C. Smid Daniel M. Weary Joao H.C. Costa Marina A.G. von Keyserlingk 《Journal of dairy science》2018,101(2):1448-1455
Dairy cows display a partial preference for being outside, but little is known about what aspects of the outdoor environment are important to cows. The primary aim of this study was to test the preference of lactating dairy cattle for pasture versus an outdoor sand pack during the night. A secondary aim was to determine whether feeding and perching behavior changed when cows were provided outdoor access. A third objective was to investigate how the lying behavior of cows changed when given access to different outdoor areas. Ninety-six lactating pregnant cows were assigned to 8 groups of 12 animals each. After a baseline phase of 2 d in which cows were kept inside the freestall barn, cows were habituated to the outdoor areas by providing them access to each of the 2 options for 24 h. Cows were then given access, in random order by group, to either the pasture (pasture phase) or the sand pack (sand phase). As we tested the 2 outdoor options using space allowances consistent with what would be practical on commercial dairy farms, the space provided on pasture was larger (21,000 m2) than that provided on the sand pack (144 m2). Cows were tested at night (for 2 nights in each condition), from 2000 h until morning milking at approximately 0800 h, as preference to be outdoors is strongest at this time. During the next 3 nights cows were given access to both outside options simultaneously (choice phase). Feeding and perching behaviors were recorded when cows were indoors during the day and night periods. Lying behavior was automatically recorded by HOBO data loggers (Onset, Bourne, MA). Cows spent more time outside in the pasture phase (90.0 ± 5.9%) compared with the sand phase (44.4 ± 6.3%). When provided simultaneous access to both options, cows spent more time on pasture than on the sand pack (90.5 ± 2.6% vs. 0.8 ± 0.5%, respectively). Time spent feeding indoors during the day did not change regardless of what type of outdoor access was provided, but there was a decline in perching during the day when cows were provided access to either outdoor option at night. Lying time in the pasture phase was lower than in the baseline or sand phase. During the nighttime, lying time outside was not different between the sand (55.4 ± 7.9%) and pasture (52.0 ± 7.4%) phases. In summary, cows spent a considerable amount of time outside during the night when given the opportunity and showed a preference for a large pasture versus a small sand pack as an outdoor area. 相似文献
159.
Richard M. Salter Terence J. Brennan Daniel P. Friedman 《Computer Languages, Systems and Structures》1980,5(3-4):163-189
Hendrix's robot modeling system presented a simulation method in which time is represented as a continuous phenomenon. This paper introduces the language CONCUR, which realizes Hendrix's concept through an extension of the LISP environment. CONCUR uses generalized procedures (scenarios) operating in a data-driven mode to implement Hendrix's events. The heart of CONCUR is a generalized pattern-matcher which permits operators within the patterns to bind variables and modify the match process. We include several detailed examples in addition to an implementation of the pattern matcher. 相似文献
160.
Daniel F. Varnell Eric J. Moskala Paul C. Painter Michael M. Coleman 《Polymer Engineering and Science》1983,23(12):658-662
FT-IR spectroscopic studies have been performed in an attempt to elucidate the nature of the specific interactions occurring in miscible poly(?-caprolactone) (PCL)-poly (vinyl chloride) (PVC) blends. Studies of low molecular weight analogues, polymer/solvent mixtures and blends of PCL and α-deuterated PVC are presented. The results strongly suggest that a hydrogen bonding type of interaction between the carbonyl bond of PCL and the α-hydrogen of PVC exists in compatible PCL-PVC blends. 相似文献