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101.
This study was conducted to determine the place of historic gardens in the city of Tabriz vis-a-vis Iranian garden arts. It provides information on the historic gardens of Tabriz, which are no longer in existence, for example, ‘Saheb Abad’ Garden, ‘North’ Garden, ‘Sefa’ Garden, ‘Amir Kabir’ Garden, ‘Saheb Divan’Garden and ‘Fath Abad’ Garden, as well as four historical maps belonging to the Qajar era in the city of Tabriz. In this research, the factors influencing the design of El-Goli Garden were studied, which can be grouped into three major categories: physical, biological and cultural. After a brief study of the above factors in the city of Tabriz and its different microclimates, the types of similarities that exist relating to Iranian garden art were determined.  相似文献   
102.
Within Australian cities, social and economic inequalities manifest themselves spatially. Perceived neighbourhood disorder and neighbourhood reputation are relevant to considering the ways in which social and economic inequalities translate into place-based inequalities. This article explores the ways in which residents of two socio-economically contrasting urban areas describe and explain neighbourhood disorder and neighbourhood reputation. It draws upon qualitative data from 40 in-depth interviews, in addition to quantitative data from a postal survey. The qualitative findings highlighted how issues of neighbourhood disorder and reputation were intertwined. In both areas, participants sought to portray themselves and their neighbourhoods in positive ways, by attributing responsibility for neighbourhood disorder to people who were unlike themselves, and by highlighting places that were perceived to have worse reputations and higher levels of disorder. The findings are considered in light of Bourdieu's theory of capitals. This article indicates that both neighbourhood disorder and reputation are pathways through which social, economic and health inequities are maintained in urban areas.  相似文献   
103.
Surface roughness is one of the most important parameters governing the shear strength of rock discontinuities. Roughness types may vary based on genesis, physico-mechanical, and mineralogical properties of rocks. In this study, granite samples representing three different weathering degrees were selected to evaluate the effects of surface roughness and weathering degree on shear strength. To this aim, we determined the profile roughness coefficient (PRC), profile roughness angle (PRA), and joint roughness coefficient (JRC) for the selected fresh and weathered granite joint samples. Values of PRC were in the range of about 1.043–1.073, and PRA and JRC varied in the ranges of 16.67–21.45 and 12–18, respectively. Weathering led to the increment of joint surface roughness of the selected granitic joints due to the higher resistance of quartz crystals in the weathered matrix. However, the increment in surface roughness did not result in an increase in the shear strength. On the contrary, the shear strength of discontinuities dramatically decreased.  相似文献   
104.
Kaçar Y  Alpay E  Ceylan VK 《Water research》2003,37(5):1170-1176
In this study, pretreatment of Afyon (Turkey) alcaloide factory wastewater, a typical high strength industrial wastewater (chemical oxygen demand (COD)=26.65 kgm(-3), biological oxygen demand (BOD(5))=3.95 kgm(-3)), was carried out by wet air oxidation process. The process was performed in a 0.75 litre specially designed bubble reactor. Experiments were conducted to see the advantages of one-stage and two-stage oxidation and the effects of pressure, pH, temperature, catalyst type, catalyst loading and air or oxygen as gas source on the oxidation of the wastewater. In addition, BOD(5)/COD ratios of the effluents, which are generally regarded as an important index of biodegradability of a high-strength industrial wastewater, were determined at the end of some runs. After a 2h oxidation (T=150 degrees C, P=0.65 MPa, airflowrate=1.57 x 10(-5)m(3)s(-1), pH=7.0), the BOD(5)/COD ratio was increased from 0.15 to above 0.5 by using the salts of metals such as Co(2+),Fe(2+),Fe(2+)+Ni(2+),Cu(2+)+Mn(2+) as catalyst.  相似文献   
105.
Journal of Applied Electrochemistry - The present work reports the development of screen-printed electrode (SPE) using flexible polyester sheets modified with nanodiamond (ND), Au nanoparticles...  相似文献   
106.
Temperature dependent current‐voltage (I–V) measurements of Au/Polyvinyl Alcohol + Bi2O3/n‐Si structure were conducted between 100 and 350 K for investigating the temperature dependence of I–V characteristics and current conduction mechanisms in the structure. Series resistance of the structure is calculated using Ohm's law and Cheungs' method. Ideality factor (n) and zero‐bias barrier height (ΦBo) were obtained considering thermionic emission theory. From 100 to 350 K, n changed from 32.1 to 3.54, and ΦBo changed from 0.27 to 0.99 eV. Obtained temperature dependent values of n and ΦBo suggested that thermionic emission is not the dominant current conduction mechanism. Therefore, Ln(I)–Ln(V) curves of the studied structure were plotted for investigating current conduction mechanisms in the structure and current flow is explained considering space charge limited current. Moreover, density of interface states (Dit) in the structure were calculated and its temperature dependence was investigated such that Dit values are reduced to the order of ~1013 eV?1 cm?2 from ~1014 eV?1 cm?2 with increasing temperature. POLYM. ENG. SCI., 54:1811–1816, 2014. © 2013 Society of Plastics Engineers  相似文献   
107.
Zn–Ni composite coatings were obtained by electrochemical co-deposition of TiO2 nano-particles (mean diameter 21 nm). Zn–Ni alloy coating was also produced under the same experimental conditions for comparison. The surface morphology, crystallographic structure, and the grain size of the deposits were investigated, along with the percentage of the embedded nano-particles in Zn–Ni matrix, as a function of concentration of TiO2 nano-particles in the bath. As the titania incorporation percentage is increased, a grain refinement in the nanometer region was revealed followed enhanced microhardness values and an improvement of the content of the nickel in the alloy. Annealing of all coatings at 200 °C revealed the crystallization of the matrix accompanied by a decrease of microhardness followed by stability for 24 h. The corrosion behavior of Zn–Ni/nano-TiO2 composite coatings with various amount of particle content was mainly studied by electrochemical impedance spectroscopy in 3 % NaCl. It was seen that Zn–Ni/nano-TiO2 composite coatings exhibited higher corrosion resistances comparing to Zn–Ni alloy coating and corrosion protection improved with increasing nano-TiO2 in coatings.  相似文献   
108.
Platinum electrocatalysts were prepared using PtCl4 as a starting material and 1-decylamine, N,N-dimethyldecylamine, 1-dodecylamine, N,N-dimethyldodecylamine, 1-hexadecylamine, and 1-octadecylamine as surfactants. These surfactants were used for the first time in this synthesis to determine whether the primary and/or tertiary structure and/or chain length of the surfactants, affects the size and/or activity of the catalysts in C1–C3 alcohol electro-oxidation reactions. Electrochemical measurements (cyclic voltammetry and chronoamperometry) indicated that the highest electrocatalytic performance was observed for the Pt nanocatalysts that were stabilized by N,N-dimethyldecylamine, and this has a tertiary amine structure with a short chain length (R = C10H21). The high performance may be due to the high electrochemical surface area, Pt(0)/Pt(IV) ratio, %Pt utility, and roughness factor (R f). X-ray photoelectron spectroscopy, X-ray diffraction, atomic force microscopy, and transmission electron microscopy were used to determine the parameters that affect the catalytic activities.  相似文献   
109.
This study outlines a new sensing platform based on glassy carbon electrodes modified by gold nanoparticles (AuNPs) for the determination of heavy metal. A glassy carbon electrode was modified by chitosan stabilized AuNPs. AuNPs were prepared by reducing gold salt with a polysaccharide chitosan. Here, chitosan acted as a reducing/stabilizing agent. The AuNPs were characterized with UV–Visible absorption spectroscopy, Fourier transform infrared spectroscopy, and transmission electron microscopy. Chitosan covered AuNPs were immobilized on the glassy carbon electrode for the determination of Cu (II) in aqueous solutions. The electrochemical determination of Cu (II) ions was performed using the differential pulse voltammetry technique. Some parameters for Cu (II) determination, such as pH, preconcentration time and electrolysis potential of Cu (II), were optimized. The detection limit was calculated as 5 × 10?9 mol L?1 by means of the 3:1 current-to-noise ratio. The interference of Cr(III), Fe(II), Ni(II), Pb(II), Mg(II), Zn(II), Ba(II) ions was investigated and showed a negligible effect on the electrode response. Recovery studies were carried out using tap water.  相似文献   
110.
The thermomechanical degradation and thermostabilization of poly(lactic acid) (PLA) have been studied using subsequent extrusion cycles under different temperature profiles. Primary and secondary antioxidants were used to avoid degradation process during extrusion. Melt flow index (MFI), size exclusion chromatography (SEC), and infrared spectroscopy (FTIR) analysis were used to evaluate the degradation and stabilization of PLA. The MFI and SEC analysis show that the main thermodegradation mechanism of PLA is governed by scission reactions. FTIR analysis confirmed the SEC results and showed that the synergetic effect between primary and secondary antioxidant is a suitable way to thermostabilize the PLA. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 40023.  相似文献   
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