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161.
Presents a historical review of the term "psychology." It is noted that while the word contains Greek elements, it does not have origins in Greek antiquity. This study suggests that the word originated in the 16th century "to refer to 1 aspect of spiritual being" and was 1st used as a title of academic lectures by Philipp Melanchton (1497-1560). Further development of the term through the mid-19th century is presented, including a table providing a chronology from Melanchton through Herbert Spencer's "Principles of Psychology" (1855). (25 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
162.
Alexandre Dolgui Brigitte Finel Nikolai N. Guschinsky Genrikh M. Levin Francois B. Vernadat 《IIE Transactions》2006,38(10):869-882
A novel line balancing problem is considered. It differs from assembly line balancing problems in that the operations of each workstation are partitioned into blocks of simultaneously executed (parallel) operations. The blocks of each workstation are executed sequentially. For the line design stage considered in this paper, the compatibility (inclusion and exclusion) constraints for grouping operations into blocks and workstations as well as precedence constraints are known. The goal is to minimize a weighted sum of the number of workstations and the number of blocks while achieving a desired cycle time and satisfying all the constraints. The developed exact and heuristic methods are based on a mixed-integer programming approach. Experimental results are reported. 相似文献
163.
Yogesh Singh Chauhan Costin Anghel Francois Krummenacher Christian Maier Renaud Gillon Benoit Bakeroot Bart Desoete Steven Frere Andre Baguenier Desormeaux Abhinav Sharma Michel Declercq Adrian Mihai Ionescu 《Solid-state electronics》2006,50(11-12):1801-1813
In this work, we present for the first time, a highly scalable general high voltage MOSFET model, which can be used for any high voltage MOSFET with extended drift region. This model includes physical effects like the quasi-saturation, impact-ionization and self-heating, and a new general model for drift resistance. The model is validated on the measured characteristics of two widely used high voltage devices in the industry i.e. LDMOS and VDMOS devices, and implemented on commercial circuit simulators like SABER (Synopsys), ELDO (Mentor Graphics), Spectre (Cadence) and UltraSim (Cadence). The accuracy of the model is better than 10% for DC I–V and g–V characteristics and shows good behavior for all capacitances which are unique for these devices showing peaks and shift of peaks with bias variation. The model also exhibits excellent scalability with transistor width, drift length, number of fingers and temperature. 相似文献
164.
Francois Jeanneau 《电子设计技术》2001,(4):68
电脑和高速通信技术的功能十分强大,它们一直在改变着我们周围的世界,解决了许多问题,提供了许多新的机会,同时,也提出了严峻的挑战。让我们来看看有关数据安全性的问题吧。如果有人想要进入宾馆的客房,要上网采购,你是如何准确无误地确定他的身份呢? 相似文献
165.
166.
Shahrouz Nayebossadri Kondo Francois Aguey-ZinsouZ. Xiao Guo 《International Journal of Hydrogen Energy》2011,36(13):7920-7926
Solid state reaction between LiNH2 and LiH potentially offers a practical pathway for hydrogen supply to fuel cell powered vehicles, particularly if the reaction kinetics can be further improved. Here we performed a comparative study of the effects of selected micron and nano-sized nitrides using temperature programmed desorption, mass spectrometry, X-ray diffraction and infrared spectroscopy. It was found that both micron and nano-sized BN and TiN act as effective catalysts within the system. While an increase in the concentration of TiN reduces dehydrogenation temperature, the opposite was observed for BN catalyst. Employment of both nano and micron-sized BN catalysts resulted in an almost similar dehydrogenation temperature; but dehydrogenation temperature was decreased about 20 °C by switching from micron to nano-sized TiN. The catalytic effects of the additives were proposed to be an improvement of surface reactivity and diffusion enhancement across the interface of the reactants. However, the role of BN and TiN are different in the way that TiN is likely to improve the surface reactivity of LiNH2, while BN mainly enhances diffusion across the interface of the reactants. Our findings also indicate that TiCl3 behaves like TiN, as a catalyst in Li-N-H system. 相似文献
167.
Francois Folefack Kaze Gloria Ashuntantang Andre Pascal Kengne Aboubakar Hassan Marie Patrice Halle Wallinjom Muna 《Hemodialysis international. International Symposium on Home Hemodialysis》2012,16(4):526-531
Little is known about the challenges of routine renal replacement therapy in Sub‐Saharan Africa. We investigated the fatal and nonfatal acute hemodialysis (HD) complications in patients with end‐stage renal disease (ESRD) in two main dialysis centers in Cameroon. 1000 consecutive HD sessions incurred over a 4‐month period by 129 patients (96 men, 74%) with ESRD, receiving two weekly HD sessions of 4 hours each, were considered. Personal and clinical profiles before, during, and within 24 hours after HD sessions were used to diagnose complications. Participants were aged 7 to 80 years (mean 46 years). In all, 452 acute complications were recorded in 411 (41%) of the 1000 HD sessions. Of the 11 types of complications, hypotension (25%), muscular cramps (22%), hypertensive crisis (14%), pruritus (10%), and fever (7%) were the most frequent. Three hundred and six complications (67.7%) occurred during understaffed nighttime. The vascular access was the main bleeding site with 64%. Being diabetic and ultrafiltration rate >1000 mL/h were associated with hypotension and muscle cramps. The shorter duration in dialysis was associated with the risk of bleeding and the disequilibrium syndrome while longer duration was associated with muscle cramps. Four deaths (three from bleeding and one from disequilibrium syndrome) occurred, all during nighttime. Nearly half of dialysis sessions in these settings are associated with acute complications, some of which are fatal. Those complications occurred mostly during understaffed periods. Urgent strategies are needed to quickly solve the human capital crisis in the health care sector. 相似文献
168.
Lotfi Toubal Jean‐Christophe Cuillire Karim Bensalem Vincent Francois Papa‐Birame Gning 《Polymer Composites》2016,37(8):2342-2352
The exposition of thermoplastic composites reinforced with natural fibers to moisture and heat is likely to lower their mechanical properties and restrain their use in the design of parts. The present work is focussed on investigating the effects of hygrothermal aging on the mechanical behaviour of injected polypropylene reinforced with short hemp fibers. Moreover, the kinetic of isothermal moisture absorption has been studied for four immersion temperatures. The experimental results show that the time taken to reach saturation decreases significantly with increase in immersion temperature. These tests also reveal that moisture absorption in this type of materials does not follow Fick's law. Thus, a new model is proposed to predict this behaviour by the use of a variable coefficient of diffusion. This model is implemented using both analytical and finite element analysis (FEA) approaches. The results obtained with this new model show a very good correlation between experimental, analytical, and FEA absorption curves. POLYM. COMPOS., 37:2342–2352, 2016. © 2015 Society of Plastics Engineers 相似文献
169.
Francois K Valero A Geeraerd AH Van Impe JF Debevere J García-Gimeno RM Zurera G Devlieghere F 《Food microbiology》2007,24(1):32-43
The impact of precultural temperature and pH on the distribution of the lag phase of individual Listeria monocytogenes cells was assessed during preincubation at 7 degrees C, using a dilution protocol to obtain single cells, and optical density measurements to estimate the individual lag phase. Firstly, the pure temperature effect (37, 15, 10, 7, 4 and 2 degrees C) was investigated on a subsequent growth at 7 degrees C and pH 7.4. Secondly, low precultural temperatures (10, 7 and 4 degrees C) were combined with a controlled pH at 7.4 and 5.7 with a subsequent growth at 7 degrees C and at different pH values (7.4, 6.0 and 5.5). For all temperature-pH combinations, the individual cell lag phase was determined using a three-phase linear growth model. It was observed that at low precultural temperatures (2, 4 and 7 degrees C), a high proportion of L. monocytogenes cells were able to grow at 7 degrees C with almost no lag phase, consequently, the resulting distributions were positively skewed. Beside this, the variability observed was lower than at higher precultural temperatures. Regarding the precultural pH effect, at pH 7.4 the mean values of the lag phases were shorter at lower preincubation temperatures; while at pH 5.7 small pH transitions produced shorter individual lag phases at all precultural temperatures. The quantification of the effect of precultural conditions on the individual cell lag phase duration would improve the accuracy of the existing growth models, especially when a series of processing and storage steps are linked together in a process model or exposure assessment. Distributions will be fitted to the data for every set of conditions, generating useful tools for further risk assessment purposes. 相似文献
170.
Many wind-field mapping applications require range-resolved atmospheric velocity measurements at long range and/or with a temporal resolution sufficient to investigate turbulence. We argue that this capability can be achieved only by coherent laser radar systems that transmit energetic (>1 mJ) pulses. We describe such a system and describe single-pulse measurement of the range-resolved line-of-sight velocities, and show that the instrument-limited reproducibility of the measurements is 0.4 ms(-1). 相似文献