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81.
Abstract

Housing prices have increased substantially in some emerging markets in recent years. Turkish housing market has also experienced a boom over the last decade with rapid house price appreciations. This study is the first to employ two different house price indexes to analyze housing bubble in Turkey in two different time periods, 2010:M1–2014:M12 and 2007:M6–2014:M12. We first capture the determinants of housing price by employing Bounds test and then examine whether rising house prices have been justified by fundamentals by employing OLS/FMOLS/DOLS, Kalman filter and ARIMA models. The Bounds test results suggest that there is a long-term cointegration among house price indexes and housing rent, construction cost and real mortgage interest rate. The results imply that the Turkish housing market has experienced some cases of overvaluation, but not bubble formation. This evidence has several implications for house price dynamics and risks in the Turkish housing market. Based on Turkish experience, the study also draws policy implications for emerging housing markets.  相似文献   
82.
This work presents the synthesis and characterization of a new water‐soluble oligophenol derivative, 4‐(2‐hydroxybenzylideneamino)benzenesulfanilic acid (OSAL‐SA) and its metal complexes. The chemical structure of the water‐soluble polymer was characterized by nuclear magnetic resonance (1H NMR) and Fourier transform infrared (FTIR) spectroscopies and thermogravimetric analyses (TGAs). Pb(II), Cu(II), Co(II) complexes of the polymer were also synthesized in methanol. Characterizations of water insoluble polymer‐metal complexes were performed by FTIR, flame atomic absorption spectroscopy, and TGA. The conductivity measurements of OSAL‐SA and polymer–metal complexes were carried out by the four‐probe technique. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
83.
A hydrogen fuel cell vehicle requires fuel cells, batteries, supercapacitors, controllers and smart control units with their control strategies. The controller ensures that a control strategy predicated on the data taken from the traction motor and energy storage systems is created. The smart control unit compares the fuel cell nominal output power with the vehicle power demand, calculates the parameters and continually adjusts the variables. The control strategies that can be developed for these units will enable us to overcome the technological challenges for hydrogen fuel cell vehicles in the near future. This study presents the best hydrogen fuel cell vehicle configurations and control strategies for safe, low cost and high efficiency by comparing control strategies in the literature for fuel economy.  相似文献   
84.
This paper describes a fully automated method of measuring the magnetization characteristics (flux linkage versus current and position) of switched-reluctance (SR) motors. The measuring scheme was developed using a graphical programming environment (LabVIEW), a data acquisition card, and external interface hardware. The graphical programming method allows a high degree of software modularity and provides the features needed fur sensor zero adjustment, data acquisition and analysis, and automated presentation of results. Furthermore, the experimental setup described in this paper can be used to obtain the magnetization characteristics of other electromechanical devices. Experimentally measured results from a test SR motor using the scheme are presented in the paper  相似文献   
85.
In this study, an overview has been presented a classification of the vehicles using hydrogen with different ways. The using of hydrogen in vehicles has been categorized into two main categories as designs in which hydrogen is burned and energy is generated by conversion to electricity. The designs of internal combustion vehicles with using hydrogen via burning, the designs of the fuel cell vehicles that using hydrogen by converting into electricity and their hybrid versions have been introduced. In the automotive industry, the structure and future advantages of hydrogen fuel cell electric vehicles have been handled in a separate title. Onboard storage, safety, the capital cost and operating cost of the different design of vehicles have been analyzed rigorously.  相似文献   
86.
87.
The effects of heating method and temperature on physical, structural and photocatalytic behaviors of TiO2 pellets prepared by conventional heating and hot isostatic pressing have been evaluated. The pellets of submicron TiO2 powders were heated to 600, 650, 700, 750 and 1000 °C using both processing methods in order to compare anatase to rutile phase transformation and densification behaviors. Bulk densities and porosities were calculated using the Archimedes method. XRD analysis were performed to calculate anatase/rutile ratios. Microstructures were characterized using SEM. Photocatalytic experiments have been performed under full spectrum irradiation. Degraded methylene blue samples were periodically monitored through UV–vis spectrophotometer to determine degradation kinetics. Anatase to rutile transformation is slightly faster and densification is better for lower temperatures for conventional heating, however HIPing gives better densification above 750 °C as it also retards rutile transformation. Mixed phase structures and HIPed samples showed the best photocatalytic performance which makes this method advantageous.  相似文献   
88.
Industrial robots, which enable manufacturing firms to produce high-quality products in a cost-effective manner, are important components of advanced manufacturing technologies. The performance of industrial robots is determined by multiple and conflicting criteria that have to be simultaneously considered in a robust selection study. In this study, a decision model based on fuzzy linear regression is presented for industrial robot selection. Fuzzy linear regression provides an alternative approach to statistical regression for modelling situations where the relationships are vague or the data set cannot satisfy the assumptions of statistical regression. The results obtained by employing fuzzy linear regression are compared with those of earlier studies applying different analytical methods to a previously reported robot selection problem.  相似文献   
89.
A formulation based on enriched reproducing kernel particle method is proposed for analysing non‐homogenous piezoelectric structures with arbitrarily shaped material interfaces. The interfaces are represented using a set of cubic spline segments, each of which is defined by the co‐ordinates and the slopes of its two end‐nodes. Special enrichment functions are introduced within the reproducing kernel particle method, in order to capture discontinuities of strain and electric fields at the material interfaces. Several validation examples are provided to demonstrate the veracity and the utility of the proposed numerical method. Copyright © 2006 John Wiley & Sons, Ltd  相似文献   
90.
Schiff base derivate 4-[(4-phenylazo-phenyimino)-methyl]-phenol (4-PPMP) monomer was synthesized by condensation reaction and the chemical structure of the monomer has been characterized by UV–vis, FT-IR, 1H NMR spectroscopies. 4-PPMP readily dissolves in 1,4-dioxane, THF, DMF, diethyl ether, chloroform and DMSO. Its solubility in methanol and ethanol is much lower. Enzymatic oxidative polymerization of azobenzene derivate 4-[(4-phenylazo-phenyimino)-methyl]-phenol using horseradish peroxidase (HRP) in the presence of hydrogen peroxide as catalyst and oxidizing agent was carried out in various solvents (acetone, methanol, ethanol, N,N-DMF, and 1,4-dioxane) and phosphate buffers (pH 6, 6.8, 7, and 7.2) at room temperature. Studies have shown that a black polymer having a melting point of 290 °C was successfully produced in good yields by utilizing aqueous 1,4-dioxane as the solvent at pH 6. Poly(4-[(4-phenylazo-phenyimino)-methyl]-phenol) P(4-PPMP) shows good solubility in 1,4-dioxane, DMF and DMSO but it is only sparingly soluble in chloroform, THF, methanol and ethanol. P-(4-PPMP) is insoluble in diethyl ether. Characterization of P-(4-PPMP) was carried out via UV–vis, FT-IR, 1H NMR, elemental analysis and SEC measurements. The number-average molecular weight (Mn), weight-average molecular weight (Mw) and polydispersity index (PDI) of the polymer were determined to be 7970.4, 8146.2 and 1.02 g mol?1, respectively. FT-IR and 1H NMR studies confirmed the presence of phenylene and oxyphenylene units with in the polymer backbone. The optical band gaps (Eg) of 4-PPMP and P-(4-PPMP) were calculated as 3.69 and 3.36 eV, respectively.  相似文献   
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