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121.
With the emergence of advanced Internet technologies, access to scientific literature is evolving at an unprecedented pace. While the number of peer-reviewed publications is growing exponentially, unpublished technical reports, dissertations and other forms of grey literature are becoming increasingly accessible for researchers across the world. Research organizations and universities are capitalizing on this opportunity, actively making their research available on the Internet. At the National Research Council, the Institute for Research in Construction ensures that all fire-related literature produced is stored in an Institutional Repository and posted on the Web in a freely available manner. In doing so, this system has provided fire researchers with a vehicle to improve visibility of their research, having pronounced advantages. For the fire community, the material is an excellent source of scholarly articles, reports, technical data and conference papers. A close examination of the Institute’s fire-related literature in Google Scholar reveals citation patterns which illustrate the value of open-access, free literature to fire researchers.  相似文献   
122.
BACKGROUND: The reliability of cardiac output obtained with the bolus technique is a problem. OBJECTIVES: To compare measurements of cardiac output measured with bolus and continuous techniques in patients with low cardiac output and to determine if measurements obtained with the continuous technique increased the number of subsequent clinical decisions. METHODS: In 60 intensive care patients, a nurse recorded a single continuous cardiac output measurement and then obtained the mean of 3 consecutive bolus determinations. The medical records of these 60 patients (experimental group) for the next 48 hours and of 60 other patients with regular or mixed venous oximetry catheters (control group) were reviewed to assess the occurrence of cardiac output events and the frequency of clinical decisions based on the events. RESULTS: Mean cardiac output was 4.46 L/min by the continuous technique and 5.20 L/min by the bolus technique (P = .011) for the experimental group. Median bias between the 2 types of measurements was -0.10 L/min (P = .79). Twenty-three of the pairs (38%) had an absolute percent difference greater than 15%. Of these, 18 (78%) had a higher bolus reading. Treatment decisions per 48 hours were 9.9 for the experimental group and 8.6 for the control group (P = .014). Median length of stay was 2 days less in the experimental group (P = .02), and mean highest cardiac output was 0.81 L/min higher (P = .009). CONCLUSIONS: Measurements of cardiac output determined with the continuous technique may be more precise than measurements determined with the bolus technique. Continuous cardiac output information increases the number of treatment decisions and actions that may shorten hospital length of stay.  相似文献   
123.
Abstract.

The detectability of settlements and factors influencing their visibility are explored using imagery from two side-looking airborne radar systems. K-band and X-band imagery of diverse areas in the United States are examined to discover the minimum population needed for a settlement to be consistently detected. The percentage of settlements visible by size of population are calculated and omission/commission errors analysed. Particular attention is devoted to the effects of environmental modulation and a near-, mid-, or far-range location, but the factors of scale, resolution, and system are also addressed.  相似文献   
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Informed by data on the dose-response effect, the authors assessed use of psychotherapy in the Veterans Health Administration (VA). The authors identified 410,923 patients with newly diagnosed depression, anxiety, or posttraumatic stress disorder using VA databases (October 2003 through September 2004). Psychotherapy encounters were identified by Current Procedural Terminology codes for the 12 months following patients' initial diagnosis. Psychotherapy was examined for session exposure received within the 12-month follow-up period and time (in days) between diagnosis and treatment. Of the cohort, 22% received at least one session of psychotherapy; 7.9% received four or more sessions; 4.2% received eight or more sessions; and 2.4% received 13 or more sessions. Delays between initial mental health diagnosis and initiation of care averaged 57 days. Patient variables including age, marital status, income, travel distance, psychiatric diagnosis, and medical-illness burden were significantly related to receipt of psychotherapy. Treatment delays and general underuse of psychotherapy services are potential missed opportunities for higher-quality psychotherapeutic care in integrated health care settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
127.
This article addresses what factors best motivate individuals to work toward shared goals. We propose that when individuals do not identify highly with a group, their contributions will mimic others': An emphasis on things done will increase their contributions toward achieving a goal, because such emphasis suggests the goal is worth pursuing. Conversely, we propose that when individuals identify highly with a group, their contributions will compensate for others': An emphasis on things left undone will increase their own contributions, because missing contributions suggest insufficient progress toward a goal they already consider worthwhile. Five studies lend support to these predictions by measuring contributions to goals centered on idea generation and helping victims of various global disasters (earthquake in Haiti, wildfires in Southern California, rioting in Kenya). (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
128.
This paper is concerned with the instrumentation and technology of fault detection and isolation (FDI) in process valves and actuators. A classification of faults in process valves and actuators is followed by a brief review of EDI techniques. Artificial neural networks (ANNs) are classified and introduced as an effective way of modelling valves and actuators, which are severely nonlinear components. Experimental results obtained from tests conducted on a double acting, twin piston rack-and-pinion actuator, are presented.  相似文献   
129.
In mammalian cells, the predominant pathway of chromosomal integration of exogenous DNA is random or illegitimate recombination; integration by homologous recombination is infrequent. Homologous recombination is initiated at double-strand DNA breaks which have been acted on by single-strand exonuclease. To further characterize the relationship between illegitimate and homologous recombination, we have investigated whether illegitimate recombination is also preceded by exonuclease digestion. Heteroduplex DNAs which included strand-specific restriction markers at each of four positions were generated. These DNAs were introduced into mouse embryonic stem cells, and stably transformed clones were isolated and analyzed to determine whether there was any strand bias in the retention of restriction markers with respect to their positions. Some of the mismatches appear to have been resolved by mismatch repair. Very significant strand bias was observed in the retention of restriction markers, and there was polarity of marker retention between adjacent positions. We conclude that DNA is frequently subjected to 5'-->3' exonuclease digestion prior to integration by illegitimate recombination and that the length of DNA removed by exonuclease digestion can be extensive. We also provide evidence which suggests that frequent but less extensive 3'-->5' exonuclease processing also occurs.  相似文献   
130.
Summary A procedure for fractionating milk fat from a solvent at low temperatures has been developed. This procedure consists of freezing out fractions of the fat from solvent (Skelly Solve A) at progressively lower temperatures —7°, —13°, —23°, —53°C., with the remaining filtrate taken as a final fraction. In physical appearance these fractions vary from a dry white powder to a reddish-yellow oil; in melting point from 53°C. to —10.6°C.; in iodine number from 8.29 to 58.37; and in saponification equivalent from 262.8 to 235.2. The saponification equivalents do not change in the same order as the other properties mentioned. This fat fractionation effects a simplification of milk fat and makes available less complex portions of the natural glyceride mixtures for detailed study of the composition, configuration, and other properties. Some of these studies are now being carried out and will be reported later.  相似文献   
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