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1.
2.
V. S. Ramachandran 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1972,22(11):1125-1138
The hydration characteristics of 3CaO.SiO2 or β2CaO.SiO2 are studied by an addition of 0.0, 0.1, 0.5 or 1.0% triethanolamine. The amount of Ca(OH)2 found at 1, 3, 7 or 28 days was in the order C3S + 0% TEA > C3S +0.1% TEA > C3S + 0.5% TEA > C3S+1.0% TEA, irrespective of whether lime was estimated by X-ray, DTA, TGA or chemical analysis. The rate of hydration, in terms of the disappearance of 3CaO.SiO2, showed that hydration proceeded faster in the presence of TEA after 1 day. Additions of TEA increase the induction period, promote the formation of a C-S-H with higher CaO/SiO2 ratio, increase the formation of non-crystalline Ca(OH)2 and enhance the surface area of the hydrated silicate product. 相似文献
3.
VS Ramachandran 《Canadian Metallurgical Quarterly》1995,4(1):22-51
Patients with right parietal lesions often deny their paralysis (anosognosia), but do they have "tacit" knowledge of their paralysis? I devised three novel tests to explore this. First, the patients were given a choice between a bimanual task (e.g., tying shoe laces) vs a unimanual one (e.g., threading a bolt). They chose the former on 17 of 18 trials and, surprisingly, showed no frustration or learning despite repeated failed attempts. I conclude that they have no tacit knowledge of paralysis (or, if such knowledge exists, it is not available for this particular task). Second, I used a "virtual reality box" to convey the optical illusion to the patient that she was moving her paralyzed left hand up and down to the rhythm of a metronome, and yet she showed no sign of surprise. Third, I irrigated patient BM's left ear canal with cold water, a procedure that is known to shift that patient's spatial frame of reference by stimulating the vestibular system. Surprisingly, this allowed her "repressed" memory of the paralysis to come to the surface; she said she had been paralyzed continuously for several days. I suggest that the vestibular stimulation produces these remarkable effects by mimicking REM sleep. These patients also employ a whole arsenal of grossly exaggerated Freudian "defense mechanisms" to account for their paralysis. To explain this, I propose that in normal individuals the left hemisphere ordinarily deals with small, local anomalies by trying to impose consistency but, when the anomaly exceeds threshold, an interaction with the right hemisphere forces a "paradigm shift." A failure of this process, in patients with right hemisphere damage, might partially account for anosognosia. Finally, I present a new conceptual framework that may help link several psychological and neurological phenomena such as Freudian defense mechanisms, vestibular stimulation, anosognosia, memory repression, visual illusions, anterograde amnesia, REM sleep, dreaming, and humor. 相似文献
4.
Cole JN Henningham A Gillen CM Ramachandran V Walker MJ 《Proteomics. Clinical applications》2008,2(3):387-410
Gram-positive streptococci are non-motile, chain-forming bacteria commonly found in the normal oral and bowel flora of warm-blooded animals. Over the past decade, a proteomic approach combining 2-DE and MS has been used to systematically map the cellular, surface-associated and secreted proteins of human pathogenic streptococcal species. The public availability of complete streptococcal genomic sequences and the amalgamation of proteomic, genomic and bioinformatic technologies have recently facilitated the identification of novel streptococcal vaccine candidate antigens and therapeutic agents. The objective of this review is to examine the constituents of the streptococcal cell wall and secreted proteome, the mechanisms of transport of surface and secreted proteins, and describe the current methodologies employed for the identification of novel surface-displayed proteins and potential vaccine antigens. 相似文献
5.
M. Sivabarathy S. Natarajan S. K. Ramakrishnan K. Ramachandran 《Bulletin of Materials Science》2004,27(5):403-407
Phase transition in L-alaninium oxalate is studied by using TG, DTA and photoacoustic spectroscopy. A sharp transition at
378 K by photoacoustics is observed whereas at the same temperature the endothermic energy change observed by TG and DTA is
not very sharp. This is discussed in detail with reference to the other known data for the organic crystals. 相似文献
6.
The rapid growth of the robotic industry has made it imperative to consider more seriously the safety aspects of robotic installations. Some work has been initiated recently in this area; a standard proposed by the Robotic Industries Association is a step in the right direction. This paper is based on an investigation of the state of the art in robotic safety, and contains an analysis of the sources of accidents, and the accident-prone operational phases of robotic installations. It forms the groundwork (literature survey) of a research project at the University of Windsor to develop a hardware/software-based safety system. It is suggested that both the robot manufacturer and the user should regard robotic safety as an important consideration. 相似文献
7.
G. Balakrishnan P. Kuppusami S. Murugesan Chanchal Ghosh Divakar Ramachandran E. Mohandas D. Sastikumar 《Transactions of the Indian Institute of Metals》2011,64(3):297-299
Multilayers of CeO2/ZrO2 thin films were deposited on Si (100) substrates using pulsed laser deposition at an optimized oxygen partial pressure of 3×10−2 mbar and at room temperature. The CeO2 layer thickness was 10 nm, while the ZrO2 layer thickness was varied as 10, 20 and 30 nm. CeO2 and ZrO2 layers were deposited alternately to obtain 25 bilayers. High temperature x-ray diffraction (HTXRD) results showed that the multilayer films had cubic ceria and tetragonal ZrO2. Thermal expansion coefficients were calculated for CeO2 and t-ZrO2 and found to increase with the decrease of ZrO2 layer thickness. The cross sectional transmission electron microscopy (XTEM) of CeO2/ZrO2 multilayer also indicated that ceria was found to be in cubic phase while zirconia contained predominantly tetragonal phase along with cubic phase in thermally annealed specimen. 相似文献
8.
Ramachandran N.P. Dinc H. Karsilayan A.I. 《Solid-State Circuits, IEEE Journal of》2003,38(6):1051-1058
An analog line driver for video applications is presented. Utilizing a class-AB error amplifier structure, the design achieved 1.2-V peak-to-peak output swing with better than 42-dB linearity for frequencies up to 5 MHz. An adaptive tuning scheme for output impedance matching using peak detection is used to provide uniform performance across line impedance variations. The circuit is designed in AMI 0.5-/spl mu/m CMOS technology and has a tuning range of 70-180 /spl Omega/ with a power consumption of about 26.4 mW at 75-/spl Omega/ load. 相似文献
9.
La Porta Thomas F. Ramjee Ramachandran Woo Thomas Sabnani Krishan K. 《Mobile Networks and Applications》1998,3(2):123-141
Wireless networks are characterized by simple end devices and limited bandwidth. One solution to address these and other limitations
of the wireless mobile environment that has been widely pursued is the placement of proxies, or agents, inside the network
to assist with application processing that would normally take place on end devices. These agents can additionally manipulate
data to reduce bandwidth requirements and assist in providing services. The design and implementation of a user agent is heavily
impacted by the application it supports. In this paper we present our experiences with user agents in two different types
of applications: telephony-based Personal Communication Services (PCS) and two-way messaging. To provide low latency service,
the PCS user agents are mobile so that they may be kept close to their end devices. The design of the PCS agents limits migration
overhead to the transfer of approximately 100 bytes of information in about 150 milliseconds. To provide advanced messaging
services, the messaging user agent supports flexible messages while limiting air interface bandwidth usage. The messaging
agents reduce uplink bandwidth usage by approximately 35% when applied to a cellular PCS system, and reduce message payloads
by 97%.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
10.
Long-period fibre gratings in specially designed birefringent few-mode fibres are used to demonstrate spectrally flat polarisers with bandwidths of 10 nm and polarisation extinction levels of 20 dB. This is enabled by the special dispersive properties of few-mode fibres, yielding fibre polarisers with performance approaching that of bulk-optic devices. 相似文献