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1.
Mri Miczi Mria Golda Balzs Kunkli Tibor Nagy Jzsef Tzsr Jnos Andrs Mtyn 《International journal of molecular sciences》2020,21(24)
The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease-19 (COVID-19) being associated with severe pneumonia. Like with other viruses, the interaction of SARS-CoV-2 with host cell proteins is necessary for successful replication, and cleavage of cellular targets by the viral protease also may contribute to the pathogenesis, but knowledge about the human proteins that are processed by the main protease (3CLpro) of SARS-CoV-2 is still limited. We tested the prediction potentials of two different in silico methods for the identification of SARS-CoV-2 3CLpro cleavage sites in human proteins. Short stretches of homologous host-pathogen protein sequences (SSHHPS) that are present in SARS-CoV-2 polyprotein and human proteins were identified using BLAST analysis, and the NetCorona 1.0 webserver was used to successfully predict cleavage sites, although this method was primarily developed for SARS-CoV. Human C-terminal-binding protein 1 (CTBP1) was found to be cleaved in vitro by SARS-CoV-2 3CLpro, the existence of the cleavage site was proved experimentally by using a His6-MBP-mEYFP recombinant substrate containing the predicted target sequence. Our results highlight both potentials and limitations of the tested algorithms. The identification of candidate host substrates of 3CLpro may help better develop an understanding of the molecular mechanisms behind the replication and pathogenesis of SARS-CoV-2. 相似文献
2.
A dynamic rcsring dnim war built to study the effects of air temperature, moisture content and grain shape on fragility of the air dried kernels. For drying rares under 0.05 kglkg min. the fragility of kernels could br described empirically as a function of the three experimental parameters. 相似文献
3.
A new analytical method has been developed for the determination of the reactive lysine content of soya bean protein. The method is based on the reaction of the free basic groups of the protein with 1-phenylazo-2 naphthol-6,8 disulphonic acid. With regard to the stoichiometry of the procedure, it has been proved, contrary to earlier reports, that the basic amino acids, histidine, arginine and lysine, each combine with one mole of the dye. After acylation with propionic anhydride lysine alone loses its dye reactivity. The usefulness of the proposed method has been demonstrated by the determination of the reactive lysine content of several untreated, heat-treated and acid-treated soya bean samples. The results show that heat damage of about 5% in reactive lysine content can be measured in 1·5 h with good reproducibility. 相似文献
4.
TESTING THE DRYING PROCESS OF SHELLED MAIZE ON ASPECTS OF NUTRITIONAL QUALITY AND THERMAL EFFICIENCY
Interactions between technology parameters of shelled maize drying and the most important characters of drying material were analysed partly on the basis of the results appeared in written literature also on the basis of the authors' test research not published yet. Theorems describing the most important physical limit of drying were published also the change of nutritional values as a function of drying technology parameters were analysed. Most important laws of different ways of energy transfer also their effect on the process of water removal besides the common ways of drying process simulation, especially considering their applicability within agricultural circumstances were discussed. One part of questions mainly not answered yet - which arise because of the specific parameters of the drying material - have been drawn up. Practically applicable results, on the basis of theoretical research activities also experimental measurements have been shortly presented. 相似文献
5.
Sápi András Rajkumar T. Kiss János Kukovecz Ákos Kónya Zoltán Somorjai Gabor A. 《Catalysis Letters》2021,151(8):2153-2175
Catalysis Letters - Heterogeneous catalysis is a chemical process achieved at solid–gas or solid–liquid interfaces. Many factors including the particle size, shape and metal-support... 相似文献
6.
In this paper, we characterize all weakly smooth uninorms (i.e., uninorms with smooth underlying operators) defined on a finite chain. It is proved that any such uninorm is determined by three unary functions and vice versa. As a by‐product, we obtain the characterizations of smooth t‐norms, smooth t‐conorms through additive generators and show that on a finite chain, there exists no counterpart of the class of uninorms continuous in ]0, 1[2. 相似文献
7.
Péter Babarczi Gergely Biczók Harald Øverby János Tapolcai Péter Soproni 《Computer Networks》2013,57(9):1974-1990
Communication networks have to provide a high level of availability and instantaneous recovery after failures in order to ensure sufficient survivability for mission-critical services. Currently, dedicated path protection (or 1 + 1) is implemented in backbone networks to provide the necessary resilience and instantaneous recovery against single link failures with remarkable simplicity. However, in order to satisfy strict availability requirements, connections also have to be resilient against Shared Risk Link Group (SRLG) failures. In addition, switching matrix reconfigurations have to be avoided after a failure in order to guarantee instantaneous recovery. For this purpose, there are several possible realization strategies improving the characteristics of traditional 1 + 1 path protection by lowering reserved bandwidth while conserving all its favorable properties. These methods either utilize diversity coding, network coding, or generalize the disjoint-path constraint of 1 + 1.In this paper, we consider the cost aspect of the traditional and the alternative 1 + 1 realization strategies. We evaluate the bandwidth cost of different schemes both analytically and empirically in realistic network topologies. As the more complex realizations lead to NP-complete problems even in the single link failure case, we propose both Integer Linear Programming (ILP) based optimal methods, as well as heuristic and meta-heuristic approaches to solve them. Our findings provide a tool and guidelines for service providers for selecting the path protection method with the lowest bandwidth cost for their network corresponding to a given level of reliability. 相似文献
8.
The present paper deals with a generalization of the homogeneous multi-server finite-source retrial queue with search for customers in the orbit. The novelty of the investigation is the introduction of balking and impatience for requests who arrive at the service facility with a limited capacity and FIFO queue. Arriving customers may balk, i.e., they either join the queue or go to the orbit. Moreover, the requests are impatient and abandon the buffer after a random time and enter the orbit, too. In case of an empty buffer, each server searches for a customer in the orbit after finishing service. All random variables involved in the model construction are supposed to be exponentially distributed and independent of each other. The primary aim of this analysis is to show the effect of balking, impatience, and buffer size on the steady-state performance measures. Concentrating on the mean response time, several numerical examples are investigated by the help of the MOSEL-2 tool used for creating the model and calculating the stationary characteristics. 相似文献
9.
Pille Mänd Lea Hallik Josep Peñuelas Pierpaolo Duce Claus Beier János Garadnai Inger Kappel Schmidt Patricia Prieto Joke W. Westerveld 《Remote sensing of environment》2010,114(3):626-297
The aim of this study was to evaluate the use of ground-based canopy reflectance measurements to detect changes in physiology and structure of vegetation in response to experimental warming and drought treatment at six European shrublands located along a North-South climatic gradient. We measured canopy reflectance, effective green leaf area index (green LAIe) and chlorophyll fluorescence of dominant species. The treatment effects on green LAIe varied among sites. We calculated three reflectance indices: photochemical reflectance index PRI [531 nm; 570 nm], normalized difference vegetation index NDVI680 [780 nm; 680 nm] using red spectral region, and NDVI570 [780 nm; 570 nm] using the same green spectral region as PRI. All three reflectance indices were significantly related to green LAIe and were able to detect changes in shrubland vegetation among treatments. In general warming treatment increased PRI and drought treatment reduced NDVI values. The significant treatment effect on photochemical efficiency of plants detected with PRI could not be detected by fluorescence measurements. However, we found canopy level measured PRI to be very sensitive to soil reflectance properties especially in vegetation areas with low green LAIe. As both soil reflectance and LAI varied between northern and southern sites it is problematic to draw universal conclusions of climate-derived changes in all vegetation types based merely on PRI measurements. We propose that canopy level PRI measurements can be more useful in areas of dense vegetation and dark soils. 相似文献
10.
Aweaving W is a simple arrangement of lines (or line segments) in the plane together with a binary relation specifying which line is above the other. A system of lines (or line segments) in 3-space is called arealization ofW, if its projection into the plane isW and the above-below relations between the lines respect the specifications. Two weavings are equivalent if the underlying arrangements of lines are combinatorially equivalent and the above-below relations are the same. An equivalence class of weavings is said to be aweaving pattern. A weaving pattern isrealizable if at least one element of the equivalence class has a three-dimensional realization. A weaving (pattern)W is calledperfect if, along each line (line segment) ofW, the lines intersecting it are alternately above and below. We prove that (i) a perfect weaving pattern ofn lines is realizable if and only ifn 3, (ii) a perfect m byn weaving pattern of line segments (in a grid-like fashion) is realizable if and only if min(m, n) 3, (iii) ifn is sufficiently large, then almost all weaving patterns ofn lines are nonrealizable.Jànos Pach has been supported in part by Hungarian NFSR Grant 1812, NSF Grant CCR-8901484, and the Center for Discrete Mathematics and Theoretical Computer Science (DIMACS), a National Science Foundation Science and Technology Center, under NSF Grant STC88-09648. Richard Pollack has been supported in part by NSA Grant MDA904-89-H-2030, NSF Grants DMS-85-01947 and CCR-8901484, and DIMACS. Emo Welzl has been supported in part by the ESPRIT II Basic Research Actions Program of the EC under Contract No. 3075 (project ALCOM) and DIMACS. 相似文献