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61.
The inclusion compound (IC) between the FDA-approved antibacterial Irgasan DP300 (Trichlosan), and β-cyclodextrin (CD) has been formed. When the Irgasan–β-CD–IC is embedded in biodegradeable/bioabsorbable films of poly(ϵ-caprolactone) (PCL) at low levels (a few wt %), they are rendered resistant to the growth of E. coli bacteria. When these same PCL films embedded with Irgasan–β-CD–IC are used as the adhesive for laminating cotton fabrics, we observe the resulting cotton laminates to also be resistant to the growth of E. coli bacteria. These results hold promise for the fabrication of bacteria-resistant polymer films and fibers, as well as antibacterial fabrics, by means of simple melt processing with Irgasan–β-CD–IC. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 300–309, 2001  相似文献   
62.
Knowing how records on a particular topic are distributed over databases is useful for both practical and theoretical reasons; however little work in this area appears to have been done. This paper examines the distribution of records on the topic of “Fuzzy Set Theory” in over 100 bibliographic databases and determines whether the distribution of records over databases is similar to the traditional Bradford hyperbolic distribution of records over journals. Different methods for counting duplicate records between and within databases have been developed. A comparison of the various distributions based on these counting methods is presented; and the distributions are compared to results of earlier studies. The results also give an indication of the number of databases necessary to search for coverage of a literature to specified percentages using the different counting techniques developed in this study.  相似文献   
63.
This paper discusses the development of a design tool using data calculated from the biomechanical functional demand on joints in older adults during activities of daily living, portrayed using a visual ‘traffic-light’ system. Whole body movements of 84 older adults were analysed using a 3D motion capture system and reaction forces were measured by force platforms, and translated into a 3D software model. Although originally intended as a tool for designers, the early evaluation of this method of visualizing the data suggests that it may be of value across those involved in the professional care of older adults.  相似文献   
64.
The rapid advances in proteomic technologies have made possible systematic analysis of hundreds to thousands of proteins in clinical samples with the promise of uncovering novel protein biomarkers for various disease conditions. We will discuss in this review article current MS and protein chip-based quantitative proteomic approaches and their application in biomarker discovery. The emphasis will be placed on new quantification strategies employing stable isotopic labeling coupled with MS/MS, and antibody-based protein chips and nanodevices. The strength and weakness of each technology are briefly highlighted.  相似文献   
65.
Spherical indentation measurements were made on enamel surfaces of intact human teeth. From the load versus depth of indentation curve Young's modulus was found to be typically 8.3×1010 Pa and the yield stress to be 3.3×108 Pa. Young's modulus was observed to vary with moisture content and with the orientation of the enamel surface. Viscoelastic behaviour was evident, also depending on the moisture content of the enamel.  相似文献   
66.
C R Hood  A A Randall 《Water research》2001,35(11):2758-2766
Anaerobic/aerobic batch experiments were conducted with a variety of volatile fatty (VFAs) and amino acids on two sequencing batch reactor populations displaying enhanced biological phosphorus removal. The batch experiments were consistent between the two systems and with the past literature: acetic and isovaleric acid were the most efficient substrates, and propionic acid was the least efficient of the 2-5 carbon VFAs (lack of acclimation was ruled out). A survey of the engineering and biochemical literature revealed that both acetic and isovaleric acid resulted in a negative reaction redox balance (i.e. it requires reducing equivalents such as NADH2) during their biotransformation to polyhydroxyalkanoates (PHAs). In addition, the survey indicated that acetic and isovaleric acid resulted in 3HB rather than 3HV or 3H2MV formation. Two possible hypotheses were put forward for evaluation: (1) it was hypothesized that a negative intracellular redox balance might result in higher PHA content since PHA biosynthesis could be sustained under anaerobic conditions (no NADH2 build up), and/or (2) it was hypothesized that 3HB resulted in greater P-uptake than other PHA forms such as 3HV.  相似文献   
67.
68.
The electroluminescence of a Type II InAs-GaSb superlattice heterodiode has been studied as a function of injection current and temperature in the spectral range between 3 and 13 /spl mu/m. The heterodiode comprises a Be-doped midwavelength infrared (MWIR) superlattice with an effective bandgap around 270 meV and an undoped long wavelength infrared (LWIR) superlattice with an effective bandgap of 115 meV. At high injection currents and elevated temperatures the band to band transitions of both superlattices can be observed. By increasing the temperature the intensity of the MWIR emission component shows a well defined thermally activated increase. The activation energy of the Beryllium doping was evaluated to be 28 meV.  相似文献   
69.
The Literature of Bibliometrics,Scientometrics, and Informetrics   总被引:4,自引:0,他引:4  
Since Vassily V. Nalimov coined the term ‘scientometrics’ in the 1960s, this term has grown in popularity and is used to describe the study of science: growth, structure, interrelationships and productivity. Scientometrics is related to and has overlapping interests with bibliometrics and informetrics. The terms bibliometrics, scientometrics, and informetrics refer to component fields related to the study of the dynamics of disciplines as reflected in the production of their literature. Areas of study range from charting changes in the output of a scholarly field through time and across countries, to the library collection problem of maintaining control of the output, and to the low publication productivity of most researchers. These terms are used to describe similar and overlapping methodologies. The origins and historical survey of the development of each of these terms are presented. Profiles of the usage of each of these terms over time are presented, using an appropriate subject category of databases on the DIALOG information service. Various definitions of each of the terms are provided from an examination of the literature. The size of the overall literature of these fields is determined and the growth and stabilisation of both the dissertation and non-dissertation literature are shown. A listing of the top journals in the three fields are given, as well as a list of the major reviews and bibliographies that have been published over the years. This revised version was published online in June 2006 with corrections to the Cover Date. This revised version was published online in June 2006 with corrections to the Cover Date. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
70.
Generally, real-time applications based on the User Datagram Protocol (UDP) generate large volumes of data and are not sensitive to network congestion. In contrast, Transmission Control Protocol (TCP) traffic is considered "well-behaved" because it prevents the network becoming congested by means of closed-loop control of packet-loss and round-trip-time. The integration of both sorts of traffic is a complex problem, and depends on solutions such as admission control that have not yet been deployed on the Internet. Moreover, the problem of quality-of-service (QoS) and resource allocation is extremely relevant from the point of view of convergence of streaming media and data transmission on the Internet. In this paper an adaptive real-time protocol based on the least mean square (LMS) algorithm is proposed to estimate the application UDP bandwidth in order to reduce the quadratic error between the packet loss and a target. Moreover, the LMS algorithm is also applied to make sure that the reduction in the average bandwidth allocated to each TCP process will not be higher than a given percentage of the average bandwidth allocated before the beginning of the UDP application.  相似文献   
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