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排序方式: 共有1054条查询结果,搜索用时 15 毫秒
31.
J. Meier P. Egelhof C. Fischer A. Himmler G. Kirchner A. v. Kienlin G. Kraus W. Henning K. W. Shepard 《Journal of Low Temperature Physics》1993,93(3-4):231-238
Status and results of a research project are reported, which aims at developing calorimetric low temperature detectors for heavy ions. The special conditions for the detection of energetic heavy ions are discussed. The response of an aluminium transition edge calorimeter, operated at about1.5K, to the impact of heavy ions was investigated. The observed energy resolutions E/E=3.9×10–3for5.9MeV/u
208
Pb-ions, E/E=1.6×10–3for4.8MeV/u
58
Ni-ions and E/E=4.3×10–3for100MeV/u
20
Ne-ions are most probably not yet limited by the intrinsic detector resolution. The present results already represent an improvement over conventional solid state detectors and ionization chambers. 相似文献
32.
Werner Henning und Karl Herrmann 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1980,171(2):111-118
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.
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
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
33.
As part of the ERDA Division of Magnetic Fusion Energy effort to achieve fusion power by the end of the century, superconducting magnet programs were established at several of the national laboratories with the support of numerous industries. Recently, these program goals have been reviewed and modified to reflect new directions in fusion research. The development of superconducting toroidal field coils has been assigned first priority for the Experimental Power Reactor. This effort, centered at ORNL, will have the extensive support of industry, so that large construction capability can be encouraged. Ohmic heating coils for tokamaks promise to be an even more difficult task, and an expanded effort will be initiated as funds become available. Magnets for mirror confinement systems should have the highest fields practical. Accordingly, LLL has been funded to develop multifilamentary niobium-tin for future might experiments. If successful, the material might complement the recent trend toward higher field tokamaks as well. Energy Storage development at LASL is concentrating on inductive storage for 1 msec discharge and a superconducting homopolar generator for 30 msec to 1 sec discharge times. The stainless steel structure is a major cost element of any magnet system. However, recent calculations have shown that a magnetic coil form affects the toroidal field ripple in the EPR by only a few parts in a thousand. Thus, an opportunity exists to characterize and develop less expensive alloys for low temperature magnet structures. 相似文献
34.
Fujio Takahashi Ernst -H. Reimerdes Henning Klostermeyer 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1977,164(3):163-166
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
35.
Hans-Arist Mehrens Henning Klostermeyer und Ernst H. Reimerdes 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1983,176(2):102-107
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.
Auszug aus der Dissertation H. A. Mehrens, TU München, 1980Sonderdruckanfragen an: Prof. Dr. H. Klostermeyer (Adresse siehe oben) 相似文献
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
36.
In this paper we study the prevalent problem of graph partitioning by analyzing the diffusion-based partitioning heuristic Bubble-FOS/C, a key component of a practical successful graph partitioner?(Meyerhenke et al. in J. Parallel Distrib. Comput. 69(9):750?C761, 2009). We begin by studying the disturbed diffusion scheme FOS/C, which computes the similarity measure used in Bubble-FOS/C and is therefore the most crucial component. By relating FOS/C to random walks, we obtain precise characterizations of the behavior of FOS/C on tori and hypercubes. Besides leading to new knowledge on FOS/C (and therefore also on Bubble-FOS/C), these characterizations have been recently used for the analysis of load balancing algorithms?(Berenbrink et al. in Proceedings of the 22nd Annual Symposium on Discrete Algorithms, pp. 429?C439, 2011). We then regard Bubble-FOS/C, which has been shown in previous experiments to produce solutions with good partition shapes and other favorable properties. In this paper we prove that it computes a relaxed solution to an edge cut minimizing binary quadratic program (BQP). This result provides the first substantial theoretical insight why Bubble-FOS/C yields good experimental results in terms of graph partitioning metrics. Moreover, we show that in bisections computed by Bubble-FOS/C, at least one of the two parts is connected. Using the aforementioned relation between FOS/C and random walks, we prove that in vertex-transitive graphs both parts must be connected components. 相似文献
37.
Fair Exchange 总被引:6,自引:0,他引:6
38.
The article addresses the issue of learning to elearn in borderless programs in a globalised learning landscape and the associated problems of scaffolding the journey across the digital divide. The authors argue that the assumption underlying such courses is that cross-cultural programs are viable because they are conceived and designed to be ‘global’, and that they assume this design to be inclusive. Henning and Van der Westhuizen claim that the global discourse in most domains can take only marginal note of the need to infuse such programs with a local semiotic—a course design criterion for which they argue. They furthermore forward the notion that the majority of the world's prospective elearners need various bridging mechanisms in order to be able to access the broader discourse and that one of these mechanisms can be explored through the metaphor of “information ecologies” as proposed by Nardi and O'Day [Nardi, B.A., & O'Day, V.L. (1999). Information ecologies. Using technology with heart. Cambridge, MA: The MIT Press]. They also conclude that issues of the learners’ trust in the course and its system need to be considered when contemplating programs for diverse target groups. By way of a case study, consisting of three portraitures of adult learners, they explore the limitations of assumed distributed cognition and claim that learning is, in reality, contained/constrained in the familiar local narrative of the novice adult elearners in a rural South African context. The case study illustrates how the resistance to technology and its power base becomes an obstacle for the students and how the support of peers becomes the main scaffolding mechanism for their entry into electronic learning environments. The findings thus show how the social context becomes the facilitator and the scaffold for elearning, more than technology and the curriculum itself. 相似文献
39.
AbstractChina has experienced a surge in innovation output in which state-owned enterprises (SOE) play an essential role. Using panel data of Chinese listed firms, this paper examines the influence of state ownership on innovation output at the firm level. Controlling for size, we analyse the effects of central and local government control on the number of firms’ patent applications in different time periods. Doing so, standard assumptions on state ownership’s inhibiting character are confirmed. However, we then qualify these findings by running separate models for different regions and sectors finding that the impact of state-control on innovation performance depends on a number of conditions. More precisely, state control of firms has a negative impact on innovation output in particular in China’s Northeast region and in mid-tech sectors whereas under other circumstances it does either not matter or can even exert a positive influence. 相似文献
40.
A cost‐effective and robust encapsulation system for chemical admixtures with delayed release mechanisms for construction materials like dry mix mortars is presented. Based on supplementary cementitious materials, a superplasticizer was encapsulated in matrix‐based encapsulations. Subsequently, the particle characteristics of the agglomerates and the release behavior of the superplasticizer were examined. The main objective of this research was to prove the functionality of such encapsulations for the future use in construction materials. The results obtained indicate that the performance of construction chemicals could be improved by encapsulation and controlled release for the future development of new construction materials. Furthermore, material characteristics of the supplementary cementitious material like the incline to excessive dusting or the materials density were improved by encapsulation. 相似文献