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91.
Given the high incidence of TBI, head injury has been studied extensively using both cadavers and anthropomorphic test devices (ATDs). However, few studies have benchmarked the response of ATD heads against human data. Hence, the objective of this study is to investigate the response of adult and ATD heads in impact, and to compare adult Hybrid III head responses to the adult head responses.  相似文献   
92.
Enhanced reductive dehalogenation is an attractive treatment technology for in situ remediation of chlorinated solvent DNAPL source areas. Reductive dehalogenation is an acid-forming process with hydrochloric acid and also organic acids from fermentation of the electron donors typically building up in the source zone during remediation. This can lead to groundwater acidification thereby inhibiting the activity of dehalogenating microorganisms. Where the soils' natural buffering capacity is likely to be exceeded, the addition of an external source of alkalinity is needed to ensure sustained dehalogenation. To assist in the design of bioremediation systems, an abiotic geochemical model was developed to provide insight into the processes influencing the groundwater acidity as dehalogenation proceeds, and to predict the amount of bicarbonate required to maintain the pH at a suitable level for dehalogenating bacteria (i.e., > 6.5). The model accounts for the amount of chlorinated solvent degraded, site water chemistry, electron donor, alternative terminal electron-accepting processes, gas release and soil mineralogy. While calcite and iron oxides were shown to be the key minerals influencing the soil's buffering capacity, for the extensive dehalogenation likely to occur in a DNAPL source zone, significant bicarbonate addition may be necessary even in soils that are naturally well buffered. Results indicated that the bicarbonate requirement strongly depends on the electron donor used and availability of competing electron acceptors (e.g., sulfate, iron (III)). Based on understanding gained from this model, a simplified model was developed for calculating a preliminary design estimate of the bicarbonate addition required to control the pH for user-specified operating conditions.  相似文献   
93.
High‐purity Ge–As–Se and Ge–As–S chalcogenide glasses were prepared by modified physical and chemical purification techniques. Using the purified glasses, step‐index fibers with a small core (~5.5 μm) and large numerical aperture (~1.3) were fabricated. When a 13.5‐cm‐long fiber was pumped with 320 fs pulses at a repetition rate of 10.5 MHz at 4.1 μm, supercontinuum spanning from ~1.8 to ~9.8 μm with a dynamic range of ±10 dB and an average power of ~3 mW was generated.  相似文献   
94.
95.
Flood Hazards     
The phenomenon of virtual space is fundamental to the way human beings relate perceptually, behaviorally, and existentially to their world. Virtuality is the presence of what is not literally present, and it thus enables the immanence of building to be annealed to the past and future, analogous form, and hypothetical possibility. In sum, virtuality is synonymous with “architecture” proper, as opposed to building simple. Through the use of gesture, the non-present is made present and given a secret status ruled by a non-classical or “grotesque” order. The principle of our access to the virtual is based on the act of reading, where the movement from the actual to the virtual is simultaneously a spatial and a philosophical transformation. Reading is not simply the translation of phonetic or iconographic characters into their linguistic equivalents, but a restructuring of the space of appearance. The origins and evolution of this “space of reading” are characterized by a distinctive architecture, and the architecture of inhabitable spaces is conditioned by this distinctive architecture: the architecture of reading is the means of reading architecture.  相似文献   
96.
An environment friendly nonlinear chalcogenide glass fiber with a Ge‐Sb‐Se core and a Ge‐Se cladding is fabricated for bright broadband mid‐infrared (MIR) supercontinuum (SC) generation. The fabricated Ge‐Sb‐Se/Ge‐Se fiber with a core diameter of 6 μm shows zero group velocity dispersion at ~4.2 μm and ~7.3 μm. By pumping the fiber with a length of 11 cm at 4.485 μm with 330 fs pulses, we achieve a SC covering the 2.2–12 μm spectral range and with an output average power of ~17 mW. This bright broadband SC source is promising for high‐resolution MIR spectroscopy.  相似文献   
97.
Silicate ceramics were shaped using tape casting (TC) and freeze tape casting (FTC) processes from three clays labeled HCR, KORS, and KCR. These clays exhibited mass content of 77% halloysite–10 Å, 29% kaolinite, and 98% kaolinite minerals, respectively. After casting the slurries, the dried tapes were sintered at 1200°C. The microstructure changes were characterized before and after sintering using scanning electron microscopy. The apparent porosity of TC samples was lower (36–47 vol.%) compared to values obtained with FTC samples (67–79 vol.%). The latter samples exhibited a highly textured porosity, with micron-sized pores aligned perpendicular to the tape surfaces. Upon sintering, the porosity of TC samples tended to decrease conversely to the case of FTC samples. Such behavior seemed related to the simultaneous effect of organic additives and ice templating. Consequently, the FTC samples showed a relatively low mechanical strength of 3–7 MPa and thermal conductivity of .14– .22 W m−1 K−1. After sintering, the mullite crystallization contributed to strengthen the bulk materials, helping to compensate for the detrimental effect of porosity on the stress to rupture and on thermal conductivity values.  相似文献   
98.
The new definition of dietary fibre introduced by Codex Alimentarius in 2008 includes resistant starch and the option to include non‐digestible oligosaccharides. Implementation of this definition required new methodology. An integrated total dietary fibre method was evaluated and accepted by AOAC International and AACC International (AOAC Methods 2009.01 and 2011.25; AACC Method 32–45.01 and 32–50.01, and recently adopted by Codex Alimentarius as a Type I Method. However, in application of the method to a diverse range of food samples and particularly food ingredients, some limitations have been identified. One of the ongoing criticisms of this method was that the time of incubation with pancreatic α‐amylase/amyloglucosidase mixture was 16 h, whereas the time for food to transit through the human small intestine was likely to be approximately 4 h. In the current work, we use an incubation time of 4 h, and have evaluated incubation conditions that yield resistant starch and dietary values in line with ileostomy results within this time frame. Problems associated with production, hydrolysis and chromatography of various oligosaccharides have been addressed resulting in a more rapid procedure that is directly applicable to all foods and food ingredients currently available.
  相似文献   
99.
The effects of heat treatment on the chemical composition of cottonseed meal (CSM), with or without the addition of cottonseed hulls (containing condensed tannins; CT), and upon reactivity of the CT were studied. Heat was applied in a forced draught oven at 100°C for 2 h. Fluorodinitrobenzene (FDNB)-available lysine, free gossypol, extractable- and bound-CT concentrations, in vitro total nitrogen (N) solubility and the in vitro rumen degradation of the two major seed proteins (52 and 48 kDa) present in cottonseed kernel (which does not contain CT) were determined. The reactivity of CT was assessed by determining N solubility and rumen degradation of cottonseed kernel proteins in the presence or absence of polyethylene glycol (PEG; molecular weight (MW) 3500), which binds and inactivates CT. Heat treatment reduced the concentrations of free gossypol and FDNB-available lysine by small amounts, reduced measurable total CT content by 13%, reduced the solubility of total N, and reduced potential degradability of the 52 and 48 kDa cottonseed storage proteins by mixed rumen microorganisms. Addition of hulls further depressed solubility of total N and ruminal degradation of the two major storage proteins in cottonseed kernel. The action of PEG in vitro indicated that only part of the depression caused by hull addition could be explained by the presence of CT in the hulls, and that the effects of CT upon N solubility and potential degradability in heated CSM were similar to that in unheated CSM. Addition of hulls also substantially reduced FDNB-available lysine. In commercially produced materials, CSM from the Brisbane mill had a lower total CT content, lower N solubility and lower ruminal protein degradation rate than CSM from the Narrabri mill, but a similar level of FDNB-available lysine. Although application of heat inactivated 13% of the total CT, such that it could no longer be extracted and detected with butanol/HCl, it did not seem to change the overall effects produced by CT in reducing N solubility and protein degradation. The effect of hull addition in reducing available lysine has considerable relevance for feeding CSM to monogastric livestock. Interactions involving heat, hulls and CT need to be further studied.  相似文献   
100.
The extractable, protein-bound and fibre-bound condensed tannin (CT) concentrations in the leaves of tropical legumes grown in both Colombia and Northern Australia were determined by the butanol–HCl method, whilst extractable CT was also determined by the vanillin–HCl method. With the exception of Senna siamea all species contained CT. The very high CT concentration found in many plants growing in Colombia may have been partly due to soil fertility being much lower at the Colombian than the Northern Australian site. Acacia boliviana , Arachis pintoi , Centrosema latidens , Senna velutina and Gliricidia sepium contained <55 g total CT kg−1 DM, which suggests that they could comprise a reasonable proportion of ruminant diets. All other species grown in South America contained 100–240 g CT kg−1 DM, which suggests that they should only be fed in small amounts as supplements to dilute the CT concentration. Leucaena species and Calliandra calothyrsus grown in Northern Australia contained intermediate concentrations of total CT (60–90 g kg−1 DM). Most species contained 70–95% of total CT as extractable CT, with the exception of Flemingia macrophylla , where 60% was extractable and 40% bound, and Gliricidia sepium , where almost all the CT was bound to protein. Values for Flemingia macrophylla differed between accessions. Extractable CT determined with vanillin–HCl was generally higher than extractable CT determined with butanol–HCl. Three accessions showed negligible (<1 g kg−1 DM) extractable CT with butanol–HCl but 10–12 g extractable CT kg−1 DM with vanillin–HCl. Two accessions showed undetectable levels of extractable CT but substantial levels of protein-bound CT, illustrating the importance of using a bound CT method for identifying forages containing CT. Relative to freeze drying, oven drying of Leucaena species reduced the concentration of extractable CT and increased concentrations of bound CT. The significance of the results for the nutrition of ruminant livestock are discussed, including the possible roles of protein-bound and fibre-bound CT.  相似文献   
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