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91.
Hydro-distilled volatile oils from the aerial parts of Satureja montana L., and Satureja subspicata Bartl. ex Vis., growing wild in Bosnia and Herzegovina, were analyzed by GC/MS. More than one hundred compounds were identified in both plant oils, representing 92.4–98.1% of the total oil. The major constituents of essential oils obtained from the plant material of S. montana, collected from two different localities, were thymol (31.7%), and geraniol (22.3%), respectively. The most abundant compounds in essential oils of S. subspicata, collected at two different stages of development, were thymol (28.6%), and spathulenol (37.6%), respectively. The screening of antimicrobial activity of essential oil samples was individually evaluated against Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa and Bacillus subtilis using a paper disc diffusion method. All tested microorganisms were inhibited by essential oil samples. Antioxidant activity was tested using the DPPH radical-scavenging method. All samples showed activity comparable to thymol, which was used as a positive probe.  相似文献   
92.
Behavioral patterns of older-adults in assisted living   总被引:1,自引:0,他引:1  
In this paper, we examine at-home activity rhythms and present a dozen of behavioral patterns obtained from an activity monitoring pilot study of 22 residents in an assisted living setting with four case studies. Established behavioral patterns have been captured using custom software based on a statistical predictive algorithm that models circadian activity rhythms (CARs) and their deviations. The CAR was statistically estimated based on the average amount of time a resident spent in each room within their assisted living apartment, and also on the activity level given by the average number of motion events per room. A validated in-home monitoring system (IMS) recorded the monitored resident's movement data and established the occupancy period and activity level for each room. Using these data, residents' circadian behaviors were extracted, deviations indicating anomalies were detected, and the latter were correlated to activity reports generated by the IMS as well as notes of the facility's professional caregivers on the monitored residents. The system could be used to detect deviations in activity patterns and to warn caregivers of such deviations, which could reflect changes in health status, thus providing caregivers with the opportunity to apply standard of care diagnostics and to intervene in a timely manner.  相似文献   
93.
This investigation deals with the compression of fibrous systems with oriented distribution of fibers into yarns, which are incorporated in a particular way into fabrics (by weft knitting technology). The compression phenomenon was investigated from both experimental and theoretical aspects. The knitted fabrics were subjected to successive compression–release cycles. According to the compression–release curves obtained, the viscoelastic response of the fibrous materials was determined. In such a way, the mechanical model based on van Wyk's compression theory was applied successfully to determine the compression hysteresis, although it is considered that the theory does not explain mechanical hysteresis of fiber assembly. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers  相似文献   
94.
In sensor networks, it is crucial to design and employ energy-efficient communication protocols since nodes are battery-powered, and thus their lifetimes are limited. We propose a data dissemination protocol for periodic data updates in wireless sensor networks, called SAFE (sinks accessing data from environments), which attempts to save energy through data delivery path sharing among multiple sinks that have common interests. Simulation results show that the proposed protocol is energy-efficient as well as scalable to a large sink population.  相似文献   
95.
We investigated whether a functional insertion/deletion (I/D) polymorphism of angiotensin-converting enzyme (ACE) influenced antipsychotic treatment. At baseline, and after 8 weeks of treatment with various antipsychotic medications, we assessed patients’ Positive and Negative Syndrome Scale (PANSS) scores, PANSS factors, and metabolic-syndrome-related parameters (fasting plasma lipid and glucose levels, and body mass index). A total of 186 antipsychotic-naïve first-episode psychosis patients or nonadherent chronic psychosis individuals (99 males and 87 females) were genotyped by polymerase chain reaction analysis. The ACE-I/D polymorphism was significantly associated with changes in PANSS psychopathology only (p < 0.05). Compared to ACE-II homozygous males, ACE-DD homozygous and ACE-ID heterozygous males manifested significantly greater decreases in PANSS positive score, PANSS excitement factor, and PANSS cognitive factor. ACE-DD homozygous females manifested higher decreases in PANSS depression factor compared to ACE-II homozygous and ACE-ID heterozygous females. The polymorphism’s effect size was estimated as moderate to strong, while its contribution to the PANSS psychopathology ranged from ~5.4 to 8.7%, with the lowest contribution observed for PANSS positive score changes and the highest for PANSS depressive factor changes. Our results indicate that ACE-I/D polymorphism had a statistically significant but weak gender-specific impact on psychopathology data, and showed no association between ACE-I/D polymorphism and metabolic-syndrome-related parameters.  相似文献   
96.
Distributed real-time systems of the future will require specialized network architectures that incorporate new classes of services and protocols in order to support time-constrained communication. In this paper, we propose a new local area network architecture for such systems. This four-layered architecture is characterized by new classes of connection-oriented and connectionless services that take into account the timing constraints of messages. We describe various aspects of the logical link control layer of the architecture and various real-time protocols that may be employed at the medium access control layer in order to support the new classes of services. We also describe a homogeneous approach to the implementation of medium access control protocols to support both connection-oriented and connectionless services, based on a uniform window splitting paradigm.  相似文献   
97.
Sensors and actuators are physical components often subjected to non‐permissible or unexpected deviations from nominal operating conditions. This paper discusses the application of additive fault detection and isolation (FDI) methods developed for linear and stationary systems on a nonlinear non‐stationary system consisting of an electronic amplifier with a DC motor. A temperature‐dependent viscous friction coefficient, as well as the non‐linearity induced by dry friction, makes the system nonlinear. Residuals were designed using two fundamental residual‐enhancement approaches: synthesis of structured residuals and synthesis of directional residuals. A comparative analysis of the results was performed applying four different techniques for residual transformation synthesis. The paper proposes suitable filtering and translation of the structured and directional residuals that enhance FDI, performance. A limiting factor in the application of directional residuals, relating to the number of different faults, which may have independent directions during FDI, is illustrated. The entire procedure is demonstrated on a simple model of a permanent‐magnet DC motor with a suitable amplifier. This laboratory system is often encountered in electrical engineering laboratories, and accordingly, the results can be used as useful educational material for student training in FDI. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
98.
We introduce complex order fractional derivatives in models that describe viscoelastic materials. This cannot be carried out unrestrictedly, and therefore we derive, for the first time, real valued compatibility constraints, as well as physical constraints that lead to acceptable models. As a result, we introduce a new form of complex order fractional derivative. Also, we consider a fractional differential equation with complex derivatives, and study its solvability. Results obtained for stress relaxation and creep are illustrated by several numerical examples.  相似文献   
99.
100.
A three-dimensional electrode cell with cross-flow of current and electrolyte is modelled for galvanostatic and pseudopotentiostatic operation. The model is based on the electrodeposition of copper from acidified copper sulphate solution onto copper particles, with an initial concentration ensuring a diffusion-controlled process and operating in a batch recycle mode. Plug flow through the cell and perfect mixing of the electrolyte in the reservoir are assumed. Based on the model, the behaviour of reacting ion concentration, current efficiency, cell voltage, specific energy consumption and process time on selected independent variables is analysed for both galvanostatic and pseudopotentiostatic modes of operation. From the results presented it is possible to identify the optimal values of parameters for copper electrowinning.List of symbols a specific surface area (m–1) - A cross-sectional area (mu2) - a a Tafel constant for anode overpotential (V) - a II Tofel constant for hydrogen evolution overpotential (V) - b a Tafel coefficient for anode overpotential (V decade–1) - b H Tafel coefficient for hydrogen evolution overpotential (V decade–1) - C e concentration at the electrode surface (m) - C L cell outlet concentration (m) - C 0 cell inlet concentration (m) - C 0 0 initial cell inlet concentration att = 0 (m) - d p particle diameter (m) - e, e p current efficiency and pump efficiency, respectively - E specific energy consumption (Wh mol–1) - E solution phase potential drop through the cathode (V) - F Faraday number (C mol–1) - h interelectrode distance (m) - i, i L current density and limiting current density, respectively (A m–2) - I, I L current and limiting current, respectively (A) - I H partial current for hydrogen evolution (A) - k L mass transfer coefficient (m s–1) - L bed height (m) - l bed depth (m) - M molecular weight (g mol–1) - N power per unit of electrode area (W m–2) - n exponent in Equation 19 - P pressure drop in the cell (N m–2) - Q electrolyte flow rate (m3 h–1) - R Universal gas constant (J mol–1 K–1) - r e electrochemical reaction rate (mol m–2 h–1) - t c critical time for operating current to reach instantaneous limiting current (s) - t p process time to reach specified degree of conversion (s) - T temperature (K) - u electrolyte velocity (m s–1) - U total cell voltage (V) - U 0 reversible decomposition potential (V) - U ohm ohmic voltage drop between anode and threedimensional cathode (V) - V volume of electrolyte (m3) - z number of transferred electrons Greek letters ratio of the operating and limiting currents - A, a anodic activation overpotential (V) - c, e cathodic concentration overpotential (V) - bed voidage - H void fraction of hydrogen bubbles in cathode - constant (Equation 2) - 0 electrolyte conductivity (ohm–1 m–1) - v electrolyte kinematic viscosity (m2 s–1) - d diaphragm voltage drop (V) - H voltage drop due to hydrogen bubble containing electrolyte in cathode (V) - electrolyte density (kg m–3) - p particle density (kg M–3) - reservoir residence time (s)  相似文献   
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