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排序方式: 共有591条查询结果,搜索用时 218 毫秒
1.
Tobin David L.; Johnson Craig; Steinberg Stacey; Staats Marian; Dennis Amy Baker 《Canadian Metallurgical Quarterly》1991,100(1):14
Investigated a multifactorial approach to the assessment of bulimia nervosa by means of hierarchical factor analysis. 245 bulimia nervosa patients and 68 patients with either anorexia nervosa or eating disorders not otherwise specified were administered a self-report battery that was organized into 21 dimensions relevant to eating disorder patients. When dimensions from this battery were subjected to hierarchical factor analysis, support for bulimia nervosa as a unique diagnostic category was obtained. However, the emergence of 3 secondary factors and 6 primary factors suggests that bulimia nervosa can also be described more complexly. The emergence of a multifactorial model of bulimia nervosa that incorporates several existing unidimensional models suggests the potential for both divergent and complicated clinical presentation in bulimia nervosa patients. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
Cunningham Stacey C.; Corrigan Sheila A.; Malow Robert M.; Smason Ivan H. 《Canadian Metallurgical Quarterly》1993,7(4):246
Assessed the differences between cocaine- and cocaine-plus-alcohol-dependent inpatients along several psychological variables. Of the 144 men that served as Ss, 113 were cocaine dependent and 31 were dependent on both cocaine and alcohol (CD-AD). CD-AD Ss showed significantly more symptoms of depression and anxiety and were more likely to have antisocial and avoidant personality disorders. The CD-AD group scored higher overall on the MMPI clinical scales. Results suggest that patients dependent on both cocaine and alcohol require increased attention to psychopathology during treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
The effect of trap design, trap color, and a mixture of isothiocyanates on the capture of Ceutorhynchus assimilis (Paykull) was studied in a series of field experiments. Unbaited yellow water traps, a yellow sticky box trap, and a yellow sticky card trap, mounted vertically, or at 45° to the vertical with the yellow card facing upwards were effective for capturing seed weevils, but a horizontal yellow sticky card trap caught few. White, green, and black traps were unattractive. During migratory periods, trap catch could be enhanced two to four times with a lure consisting of a mixture of allyl, 3-butenyl, 4-pentenyl, and 2-phenylethyl isothiocyanates, but this bait did not attract in a trap with ineffective design. The sticky card trap, mounted at 45° to the vertical and baited with the isothiocyanate mixture, may be useful for monitoring movement of C. assimilis during migratory periods. However, during the colonization phase, lures of either a mixture of isothiocyanates or of allyl isothiocyanate alone were not attractive. 相似文献
4.
This paper describes the design, construction and performance of a high temperature thermal regenerator of annular geometry with radial air flow present. This regenerator has possible application to the efficient exploitation of high temperature gas reactions and in particular to the fixation of atmospheric nitrogen for which this investigation was made. A mathematical model is formulated for the transient heat transfer between a fluid and an annular solid matrix with reversing flows and is solved numerically. The model is used to predict and analyse the operating performance of the regenerator over a range of flow rates (650 Kg/hr maximum), flow reversal periods (100 seconds maximum) and core temperatures (1431°C maximum). The model is tested by comparison of the theoretical and observed regenerator effectiveness, internal bed temperature profiles and the bed pressure drop under conditions of cyclic equilibrium. Apparent effective heat transfer coefficients for the regenerator packing are obtained and compared with an empirical correlation based on independant measurements. 相似文献
5.
Liu Xinke Kao Evan Haraldsson Henrik Ballweber Megan Martin Alastair Li Youxiang Wang Yuting Saloner David 《Magma (New York, N.Y.)》2021,34(5):659-666
Magnetic Resonance Materials in Physics, Biology and Medicine - To determine the intra-individual flow variation in serially acquired studies, and the influence of this variation on subsequent... 相似文献
6.
Arregui-Dalmases C Del Pozo E Stacey S Kindig M Lessley D Lopez-Valdes F Forman J Kent R 《Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine》2011,225(7):688-695
While rupture of the aorta is a leading cause of sudden death following motor vehicle crashes, the specific mechanism that causes this injury is not currently well understood. Aortic ruptures occurring in the field are likely due to a complex combination of contributing factors such as acceleration, compression of the chest, and increased pressure within the aorta. The objective of the current study was to investigate one of these factors in more detail than has been done previously; specifically, to investigate the in situ intra-aortic pressure generated during isolated belt loading to the abdomen. Ten juvenile swine were subjected to dynamic belt loads applied to the abdomen. Intraaortic pressure was measured at multiple locations to assess the magnitude and propagation of the resulting blood pressure wave. The greatest average peak pressure (113.6 +/- 43.5 kPa) was measured in the abdominal aorta. Pressures measured in the thoracic aorta and aortic arch were 70 per cent and 50 per cent, respectively, that measured in the abdominal aorta. No macroscopic aortic trauma was observed. To the authors' knowledge the present study is the first one to document the presence, propagation, and attenuation of a transient pressure wave in the aorta generated by abdominal belt loading. The superiorly moving wave is sufficient to generate hydrostatic and intimal shear stress in the aorta, possibly contributing to the hypothesized mechanisms of traumatic aortic rupture. 相似文献
7.
James R. Wallace Stacey D. Scott Taryn Stutz Tricia Enns Kori Inkpen 《Personal and Ubiquitous Computing》2009,13(8):569-581
Multi-display groupware (MDG) systems, which typically comprise both public and personal displays, promise to enhance collaboration,
yet little is understood about how they differ in use from single-display groupware (SDG) systems. While research has established
the technical feasibility of MDG systems, evaluations have not addressed the question of how users’ behave in such environments,
how their interface design can impact group behavior, or what advantages they offer for collaboration. This paper presents
a user study that investigates the impact of display configuration and software interface design on taskwork and teamwork.
Groups of three completed a collaborative optimization task in single- and multi-display environments, under different task
interface constraints. Our results suggest that MDG configurations offer advantages for performing individual task duties,
whereas SDG conditions offer advantages for coordinating access to shared resources. The results also reveal the importance
of ergonomic design considerations when designing co-located groupware systems. 相似文献
8.
Psychotherapy studies published in the Journal of Counseling Psychology (JCP) and the Journal of Consulting and Clinical Psychology (JCCP) between 1978 and 1992 were examined. Differences were found between the 2 journals. JCP published mostly process, outcome, and analog research, whereas JCCP published mostly outcome research. Most process and process-outcome studies across journals were of individual, brief therapy. Across the years, more diversity was evident in samples used in process research in terms of student status, gender, and race of clients and therapists. Three content areas were prominent in the process measures and classic studies: therapist techniques, therapist influence, and facilitative conditions. Lists are provided of the frequently used measures, most productive authors, and classic studies in process research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
High Figure of Merit (FOM) of Bragg Modes in Au‐Coated Nanodisk Arrays for Plasmonic Sensing 下载免费PDF全文
Maxime Couture Thibault Brulé Stacey Laing Wenli Cui Mitradeep Sarkar Benjamin Charron Karen Faulds Wei Peng Michael Canva Jean‐Francois Masson 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(38)
Gold‐coated nanodisk arrays of nearly micron periodicity are reported that have high figure of merit (FOM) and sensitivity necessary for plasmonic refractometric sensing, with the added benefit of suitability for surface‐enhanced Raman scattering (SERS), large‐scale microfabrication using standard photolithographic techniques and a simple instrumental setup. Gold nanodisk arrays are covered with a gold layer to excite the Bragg modes (BM), which are the propagative surface plasmons localized by the diffraction from the disk array. This generates surface‐guided modes, localized as standing waves, leading to highly confined fields confirmed by a mapping of the SERS intensity and numerical simulations with 3D finite element method. The optimal gold‐coated nanodisk arrays are applied for refractometric sensing in transmission spectroscopy with better performance than nanohole arrays and they are integrated to a 96‐well plate reader for detection of IgY proteins in the nanometer range in PBS. The potential for sensing in biofluids is assessed with IgG detection in 1:1 diluted urine. The structure exhibits a high FOM of up to 46, exceeding the FOM of structures supporting surface plasmon polaritons and comparable to more complex nanostructures, demonstrating that subwavelength features are not necessary for high‐performance plasmonic sensing. 相似文献
10.
Direct Method Based Control System for an Autonomous Quadrotor 总被引:1,自引:0,他引:1
Ian D. Cowling Oleg A. Yakimenko James F. Whidborne Alastair K. Cooke 《Journal of Intelligent and Robotic Systems》2010,60(2):285-316
This paper proposes a real time control algorithm for autonomous operation of a quadrotor unmanned air vehicle. The quadrotor
is a small agile vehicle, which as well as being a excellent test bed for advanced control techniques could also be suitable
for internal surveillance, search and rescue and remote inspection. The proposed control scheme incorporates two key aspects
of autonomy; trajectory planning and trajectory following. Using the differentially-flat dynamics property of the system,
the trajectory optimization is posed as a non-linear constrained optimization within the output space in the virtual domain,
not explicitly related to the time domain. A suitable parameterization using a virtual argument as opposed to time is applied,
which ensures initial and terminal constraint satisfaction. The speed profile is optimized independently, followed by the
mapping to the time domain achieved using a speed factor. Trajectory following is achieved with a standard multi-variable
control technique and a digital switch is used to re-optimize the reference trajectory in the event of infeasibility or mission
change. The paper includes simulations using a full dynamic model of the quadrotor demonstrating the suitability of the proposed
control scheme. 相似文献