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941.
Pei‐Chi Wu 《Software》2001,31(12):1125-1130
ISO 10646 Universal Character Set (UCS) is a 31‐bit coding architecture that covers symbols in most of the world's written languages. Identifiers in programming languages are usually defined by using alphanumeric characters of ASCII, which represent mainly English words. An approach for working around this deficiency is to encode multilingual identifiers into the alphanumeric range of ASCII. For case‐sensitive languages, an encoding that utilizes [0–9][A–Z][a–z] can be more space‐efficient for multilingual identifiers. This paper proposes a base62 transformation format of ISO 10646 called UTF‐62. The resulting string of UTF‐62 is within a [0–9][A–Z][a–z] range, a total of 62 base characters. UTF‐62 also preserves the lexicographic sorting order of UCS‐4. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
942.
Indicating that CBMC does not satisfy the monotonic property in terms of the number of interactions, Xu and Zhou proposed an augmented definition of CBMC by adopting cut set instead of glue methods. The augmented CBMC clearly satisfies the monotonic property. However, CBMC is designed to overcome the problem with respect to the number of interactions and, therefore, focuses on the interaction pattern, especially, member connectivity. Consequently, it does not make sense to mention the monotonic property of CBMC with respect to interaction number. Moreover, the notion of glue methods allows several interpretations on the design quality of a class. However, that meaningful interpretation is not possible for the augmented definition due to the removal of the notion of glue methods. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
943.
In this paper, a tuning formula is derived for PID control of plants with under‐damped step responses. The under‐damped systems are modeled by second‐order plus dead time transfer functions. To derive the tuning rule, the dominant pole assignment method was applied to design the PID controllers for a variety of plant models. Then, the correlation between the controller parameters and the parameters of the models was found and the tuning formula derived. Several simulation examples are given to demonstrate the effectiveness and robustness of this formula.  相似文献   
944.
In this paper, a model‐refining method is proposed to alleviate the complexity involved in specification interpretation of DES control problems. The legal constraint language is defined in terms of illegal states and events in contrast with constructing the automaton of the specification language. This method could provide a more intuitive view of the DES control problem and would be suitable for practical implementation. Two examples, which have commonly been used in the literature, are employed to show the efficiency of the proposed method. Further, under this framework, it is shown that the supremal controllable sublanguage can take a simpler form based on the concept of an illegal state set. A state‐based supervisor synthesis procedure is presented, and a simple example is provided.  相似文献   
945.
Zusammenfassung Blätter wie Früchte von 6 SortenPrunus domestica-Pflaumen enthalten hauptsächlich 3-Rutinoside, in geringerer Konzentration 3-Glucoside und 3-Galaktoside von Kämpferol und Quercetin Bowie Quercetin-3-rhamnosid. Dagegen weisen Pflaumen vonPrunus salicina (2 untersuchte Sorten) Kämpferol-3,7-bisrhamnosid und Kämpferol-3-arabinosyl-7-rhamnosid als Hauptflavonole auf. Hierdurch ist eine Unterscheidung beider Arten leicht and sicher mög-lich. Weiterhin konnten inSalicina-Pflaumen Kämpfe-rol-3-rutinosid sowie Quercetin-3-rhamnosid, -xylosid,-glucosid, -galaktosid, --l-arabinofuranosid and -rutinosid, auch Quercetin-7-rhamnosid and Kämpferol-7-glucosid nachgewiesen werden.Die Gesamtgehalte an Flavonolglykosiden lagen bei den untersuchten Pflaumensorten vonPrunus domestica (P. salicina) bei 2500–3340 (7170, 10350) ppm in Blättern and 20–52 (8, 24) in Früchten, jeweils bezogen auf Frischgewicht.
Flavonol glycosides of plums of the species Prunus domestica L. and Prunus salicina lindley12. Phenolics of fruits
Summary Leaves and fruits from 6 cultivars ofPrunus domestica plums contain mainly 3-rutinosides; in smaller concentrations the 3-glycosides and 3-galactosides of kaempferol and quercetin as well as quercetin-3-rhamnoside are present. On the other hand, in plums ofPrunus salicina (2 examined cultivars) main flavonols are kaempferol-3,7-bisrhamnoside and kaempferol-3arabinosyl-7-rhamnoside. Due to the difference in composition, differentiation of these species will be easy and reliable. Additionally kaempferol-3-rutinoside and quercetin-3-rhamnoside, -xyloside,-glucoside, -galactoside, --l-arabinofuranoside and-rutinoside, and also quercetin-7-rhamnoside and kaempferol-7-glucoside could be detected inP. salicina plums. The total content of flavonol glycosides in the investigated plums ofPrunus domestica (P. salicina) were based on fresh weight about 2500–3340 (7170, 10350) ppm in the leaves and 20–52 (8, 24) ppm in the fruits.


11. Mitt.: Henning W, Herrmann K (1980) Z Lebensm Unters Forsch 170:433–444

Auszug aus der Promotionsarbeit von W. Henning: Bestimmung der in Pflaumen, Kirschen, Pfirsichen and Aprikosen vorkommenden Flavonolglykoside unter Anwendung der Hochdruckflüssigkeitschromatographie. Diss. Univ. Hannover 1980  相似文献   
946.
Zusammenfassung Zur quantitativen Bestimmung von Coffein in biologischem Material wird ein kombiniertes Verfahren aus Dünnschichtchromatographie und Densitometrie beschrieben. Das Verfahren läßt Bestimmungen im Nanogramm-Bereich zu. Das Probenvolumen liegt unter 100 l.Die Proben — Capillarblut — werden zunächst mit dem gleichen Volumen Chloroform extrahiert. Anschließend wird das Coffein mittels Dünnschichtchromatographie von Begleitstoffen und störenden Substanzen abgetrennt. Es werden Kieselgel-60-Fertigplatten und Chlorofom/Aceton (9 + 1; v/v) als Fließmittel verwendet, dabei beträgt die Laufzeit 30 min.Die quantitative densitometrische Auswertung erfolgt durch Remissionsmessung bei 273 nm. Im Bereich von 10–60 ng Coffein/Fleck verläuft die Eichkurve linear. 1 mg/I Coffein kann noch sicher quantitativ erfaßt werden. Die Nachweisgrenze liegt bei 0,1 mg/1.
A quantitative micromethod for the caffeine determination
Summary A combined procedure with thin-layer-chromatography and densitometry is described for the quantitative estimation of caffeine in biological material. This method ist applicable in the nanogram range. Test samples of less than 100 l may be used. The samples (capillary-blood) are extracted with the same volume of chloroform. Caffeine is separated from interfering compounds by thin-layer-chromatography. Commercial silica-60-plates with chloroform/acetone (9 + 1; v/v) as solvent are used. The running time is about 30 min. The quantitative densitometric determinations are performed in the remission mode at 273 nm. In the range from 10 to 60 ng/spot the calibration curve is linear. Accurate quantitative data will be obtained even at concentrations of 1 mg/1 caffeine. The detection limit is at about 0.1 mg/1.
  相似文献   
947.
    
Summary In casein-containing agarose gels, pepsin and chymosin form radial diffusion zones; the diameters of these zones show rectilinear correlations with the logarithm of the enzyme concentration at constant time. The sensitivity for both enzymes is below 1 g. Addition of the inhibitor pepstatin A to these enzymes causes a reduction of the diameters of the diffusion zones, with large differences for both the enzymes. With this procedure, the pepsin/chymosin ratio in rennet preparations was assayed with an accuracy of ±5%. Identification of the inhibitors allows the determination of amounts in the namomole range. This method is a simple technique for the evaluation of proteinases and their inhibitors in screening systems.
Geldiffusion — eine einfache und empfindliche Technik für den Nachweis von Proteinaseinhibitoren und die Anwendung für die Bestimmung von Proteinasen in Gemischen
Zusammenfassung In caseinhaltigen Agarosegelen erzeugen sowohl Pepsin wie Chymosin radiale Diffusionszonen, deren Durchmesser bei gegebener Zeit dem Logarithmus der Enzymmenge proportional ist. Die Bestimmungsgrenze liegt für beide Enzyme unter 1 g. Bei Zugabe des Inhibitors Pepstatin A zu den Proteinasepräparaten werden die Diffusionszonen beider Proteinasen verkleinert, aber in unterschiedlichem Ausmaße. Auf dieser Basis kann in technischen Labpräparaten das Mengenverhältnis Pepsin/Chymosin mit einer Genauigkeit von ±5% bestimmt werden. Bei Umkehr der Reaktion zum Nachweis des Inhibitors sind Mengen im Bereich von 10–9 Mol sicher erfaßbar. Die Methodik ist verallgemeinerungsfähig als Screening-Test für Proteinaseinhibitoren.
  相似文献   
948.
Zusammenfassung Die Fraktionierung von Molkenproteinkonzentrat mit Aceton wurde untersucht. Der pH-Wert und die Lösungsmittelkonzentration, bei der die Fällungen durchgeführt wurden, hatten den größ-ten Einfluß auf die Zusammensetzung von Präcipitaten und Überständen. Im Bereich von 25–33% Aceton (v/v) war eine begrenzte Fraktionierung der Molkenproteine möglich:-Lactalbumin und-Lactoglobulin wurden ausgefällt, während Blutserumalbumin in Lösung blieb. Der pH-Wert (Bereich 4,5–7,0) beeinflulßte neben den Proteinfraktionen auch andere Bestandteile des Molkenkonzentrats. Mit steigendem pH-Wert verringerte sich die Gesamt-N-Ausbeute im Präcipitat und der Gehalt an Calcium nahm zu, gleichzeitig verminderte sich die Resolubilisationsfähigkeit der ausgefällten Niederschläge.
Isolation and functional properties of whey protein fractions
Summary The fractionation of whey protein concentrate by acetone was investigated. The composition of precipitates and supernates was strongly influenced by pH and acetone concentration during precipitation. A limited fractionation of the whey proteins occurred in the range of 25–33% acetone (v/v):-lactalbumins and-lactoglobulins were precipitated while blood serum albumins remained in solution. The pH value (range 4,5-7,0) influenced also other components of the whey concentrate beside the protein fractions. With increasing pH value the yield of total N in the precipitate decreased whereas the calcium content rose, this was accompanied by a decreased capability to redissolve the precipitates.


Auszug aus der Dissertation H. A. Mehrens, TU München, 1980Sonderdruckanfragen an: Prof. Dr. H. Klostermeyer (Adresse siehe oben)  相似文献   
949.
European river basin authorities are responsible for the implementation of the new river basin management plans in accordance with the European Water Framework Directive. This paper presents a new methodology framework and approach to define and evaluate environmental flow regimes in the realistic complexities that exist with multiple water resource needs at a basin scale. This approach links river basin simulation models and habitat time series analysis to generate ranges of environmental flows (e‐flows), which are evaluated by using habitat, hydropower production and reliability of water supply criteria to produce best possible alternatives. With the use of these tools, the effects of the proposed e‐flows have been assessed to help in the consultation process. The possible effects analysed are impacts on water supply reliability, hydropower production and aquatic habitat. After public agreements, a heuristic optimization process was applied to maximize e‐flows and habitat indicators, while maintaining a legal level of reliability for water resource demands. The final optimal e‐flows were considered for the river basin management plans of the Duero river basin. This paper demonstrates the importance of considering quantitative hydrologic and ecological aspects of e‐flows at the basin scale in addressing complex water resource systems. This approach merges standard methods such as physical habitat simulations and time series analyses for evaluating alternatives, with recent methods to simulate and optimize water management alternatives in river networks. It can be integrated with or used to complement other frameworks for e‐flow assessments such as the In‐stream Flow Incremental Methodology and Ecological Limits of Hydrologic Alteration. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
950.
Rapid industrialization and urbanization has led to increasing input of chemical contaminants into the aquatic environment of Malaysia. Despite the threat civilization poses to the biota, there are still very few relevant studies on ecotoxicological testing of river ecosystems. To overcome this knowledge gap, we examined lethal and genotoxic effects of sediments from different rivers of the northern Malaysia against Chironomus kiiensis, a group well represented in the aquatic fauna of this region. We exposed the larvae to sediments from Selama River (SR), Permatang Rawa River (PRR) and Kilang Ubi River (KUR) at various durations (0, 6, 12, 24 and 48 h). The larval mortality was monitored, whereas DNA damage in survivors' cells was determined using the comet assay. Pollution level indexed by the amounts of heavy metals and other organic contaminants in the sediment showed progressive increases from SR to PRR to KUR. Highly polluted sediments (PRR to KUR) were detrimental to C. kiiensis larvae, most of which did not survive following exposure for long periods. DNA analyses revealed greater damages in nuclei derived from larvae maintained on polluted sediments, in particular, those from KUR. The effects on the genomic material of C. kiiensis larvae occurred in a time‐dependent manner, with damage level increasing as exposure time progressed. Our results highlight the genotoxic properties of polluted sediments. More importantly, this study showed that C. kiiensis larvae could respond to different levels of pollution with respect to exposure time. It is concluded that C. kiiensis larvae is a potential candidate for river ecotoxicological monitoring. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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