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排序方式: 共有2122条查询结果,搜索用时 218 毫秒
991.
Samer Ghaleb Bagaeen 《Housing Studies》2006,21(1):135-150
This paper looks at the changing nature of ownership patterns in the Old City of Jerusalem from a historical perspective, the role of rent control and leasing arrangements, and assesses their impact on the maintenance and condition of property in the Old City. It investigates the nature of the institution of Muslim religious trusts (the waqf) in order to build up a picture of its transformation into a manager of housing in the Old City since 1967 focusing on the relationship between the shift of ownership from the public waqf to the private family waqf and the effects of this on the condition of the built environment. Although recent trends in the Middle East and some Muslim countries indicate a clear decline in the status of the waqf as an institution, this paper shows how, in Jerusalem, and in the Old City in particular, it has been flourishing since 1967. The paper offers some insights into the impact of the identified historical and legal factors on the condition of buildings and, by examining statistical evidence, finds a clear correlation between the ownership and use of buildings and their physical condition. 相似文献
992.
In an electricity market cleared by a merit-order economic dispatch we make use of the mixed-integer linear programming (MILP) scheme derived in Part I to find the market outcomes supported by a pure strategy Nash equilibria (NE). From these NE, we identify offer strategies in terms of gaming or not gaming that best meet the risk/benefit expectations of the participating Gencos. To do this, a number of measures of potential profit gain and loss are developed that quantify the notion of risk/benefit under the possible multiple NE. The NE identification scheme is tested on several systems of up to 30 generating units, each with four incremental cost blocks, also showing how market power is influenced by the number and size of the competing Gencos as well as by the imposed price cap. 相似文献
993.
本田新奥德赛自推出来后,一直销售不错,以其不俗的性能和俊朗的外形在MPV市场上极具竞争力,同时这个车型也是国内众多车机厂商争相开发的专车装用机的香馍馍。 相似文献
994.
Phenolic compounds (gallic acid, ellagic acid and quercetin) and carotenoids (??-carotene and retinol) were used to evaluate effects of antioxidant on refined hazelnut oil. Peroxide value (PV), free fatty acid (FFA), iodine value (IV) and color analysis were made on hazelnut oil 120?days stored in the 40?°C, light and airy condition. In oil sample PV were found at range of 78.1?C621.5 (meqO2/kg oil) in the end 120?days. Antioxidant effectiveness in hazelnut oil at the half of the storage period (60th day) was in the order: Quercetin?>???-carotene?=?gallic acid?>?ellagic acid. Antioxidative effectiveness was not observed in retinol treatment. However, FFA and IVs were determined in the range of 0.65?C0.86 (% as oleic acid) and 68?C85, respectively, at final storage. 相似文献
995.
996.
Sibel Dikmen Hasan Aslanbay Erdal Dikmen Osman Şahin 《Journal of power sources》2010,195(9):2488-2495
The structure, the thermal expansion coefficient, electrical conductivities of Ce0.8Gd0.2?xMxO2?δ (for M: Bi, x = 0–0.1, and for M: Sm, La, and Nd, x = 0.02) solid solutions, prepared for the first time hydrothermally, are investigated. The uniformly small particle size (28–59 nm) of the materials allows sintering of the samples into highly dense ceramic pellets at 1300–1400 °C. The maximum conductivity, σ700 °C around 4.46 × 10?2 S cm?1 with Ea = 0.52 eV, is found at x = 0.1 for Bi-co-doping. Among various metal-co-dopings, for x = 0.02, the maximum conductivity, σ700 °C around 2.88 × 10?2 S cm?1 with Ea = 0.67 eV, is found for Sm-co-doping. The electrolytic domain boundary (EDB) of Ce0.8Gd0.1Bi0.1O2?δ is found to be 1.2 × 10?19 atm, which is relatively lower than that of the singly doped samples. The thermal expansion coefficients, determined from high-temperature X-ray data are 11.6 × 10?6 K?1 for the CeO2, 12.1 × 10?6 K?1 for Ce0.8Gd0.2O2?δ, and increase with co-doping to 14.2 × 10?6 K?1 for Ce0.8Gd0.18Bi0.02O2?δ. The maximum power densities for the single cell based on the codoped samples are higher than that of the singly doped sample. These results suggest that co-doping can further improve the electrical performance of ceria-based electrolytes. 相似文献
997.
Farha Masood P. Chen Tariq Yasin Nighat Fatima Fariha Hasan Abdul Hameed 《Materials science & engineering. C, Materials for biological applications》2013,33(3):1054-1060
Biodegradable, biocompatible, renewable and non-toxic polyhydroxyalkanoates (PHAs) based nanoparticles are the novel nanotherapeutic tool which are used for the encapsulation of antineoplastic drugs for cancer therapy. In this study, poly-3-hydroxybutyrate-co-5 mol% 3-hydroxyvalerate (PHBV-S), poly-3-hydroxybutyrate-co-11 mol% 3-hydroxyvalerate (PHBV-11) and poly-3-hydroxybutyrate-co-15 mol% 3-hydroxyvalerate (PHBV-15) were used as a nanocarrier for encapsulation of Ellipticine (EPT). EPT is a model anticancer drug. Physicochemical characteristics such as particle size, its morphology and zeta potential of blank and EPT loaded PHBV-S, PHBV-11 and PHBV-15 nanoparticles were studied. In vitro cytotoxicity tests confirmed that the blank PHBV-S, PHBV-11 and PHBV-15 nanoparticles were demonstrating significant biocompatibility without affecting the survival of cancer cell line A549. The loading efficiency of EPT in PHBV nanoparticles was observed in the range of 39.32 to 45.65%. The % inhibition of cancer cell line A549 ranged from 64.28 to 67.77% in comparison to EPT alone in which % inhibition found to be ≤ 45.11%. The IC50 value for each of three different formulations of EPT loaded PHBV nanoparticles ranged from 1.00 to 1.31 μg/mL. The order of % inhibition of cancer cell line A549 for drug loaded nanoparticles was EPT-PHBV-15 > EPT-PHBV-S > EPT-PHBV-11. This system had demonstrated a great potential to increase the cytotoxic effect of EPT by increasing its bioavailability. 相似文献
998.
Malika Lahiani-Skiba Cécile Barbot Frédéric Bounoure Samer Joudieh Mohamed Skiba 《Drug development and industrial pharmacy》2013,39(9):1043-1058
ABSTRACTThis contribution focused on the solubility improvement of the poorly water-soluble steroid hormone progesterone which, in its natural state, presents a reduced oral bioavailability. In the first part of this study, two simple, reproducible methods that were candidates for use in the preparation of inclusion complexes with cyclodextrins were investigated. Solubility capacities of the progesterone complex with hydroxypropyl-β-CD (HPβ-CD), hydoxypropyl-γ-CD (HPγ-CD), permethyl-β-CD (PMβ-CD), and sulfobutylether-β-CD (SBEβ-CD), prepared by the freeze-drying and precipitation methods, were evaluated by Higuchi phase solubility studies. The results showed that HPβ-CD and PMβ-CD were the most efficient among the four cyclodextrins for the solubilization of progesterone, with the highest apparent stability constants. Therefore, dissolution studies were conducted on these latest progesterone/cyclodextrin complexes and physical mixtures. Two additional natural cyclodextrins, β-CD and γ-CD, were taken as references. Hence, the influence of more highly soluble derivatives of β‐CD (HPβ-CD, PMβ-CD) on the progesterone dissolution rate, in comparison to pristine β-CD, alongside an increase in the cavity width for γ-CD versus β-CD, were investigated. The dissolution kinetics of progesterone dissolved from HPβ-CD, PMβ-CD, and γ-CD revealed higher constant rates in comparison to β-CD. Therefore, the aim of the second part of this study was to investigate the possibility of improving the dissolution rate of progesterone/β-CD binary systems upon formation of ternary complexes with the hydrophilic polymer, PEG 6000, as β-CD had the smallest progesterone solubility and dissolution capacity among the four cyclodextrins studied (β‐CD, HPβ-CD, HPγ-CD and PMβ-CD). The results indicated that dissolution constant rates were considerably enhanced for the 5% and 10% progesterone/β-CD complexes in PEG 6000.The interaction of progesterone with the cyclodextrins of interest on the form of the binary physical mixtures, complexes, or ternary complexes were investigated by differential scanning calorimetry (DSC) and Fourier transformed-infrared spectroscopy (FT-IR). The results proved that progesterone was diffused into the cyclodextrin cavity, replacing the water molecules and, in case of ternary systems, that the progesterone β-cyclodextrin was well dispersed into PEG, thus improving progesterone bioavailability for subsequent oral delivery in the same way as derivatized cyclodextrins. The present work proves that ternary complexes are promising systems for drug encapsulation. 相似文献
999.
This study aims to analyse resilience and relational dynamics (competitive, cooperative and co-opetitive) within a triadic buyer–supplier–supplier context. Our central goal is to show how a buyer’s supplier–supplier relational behaviour leads to and shapes resilience of this triad. We utilised a multiple-design case approach and selected eight buyers and their suppliers from the textile industry in Turkey. By analysing a triadic context from another industry, we conducted validation analyses. Our findings showed a pattern of relationship between the resilience and the relational dynamics of a triad. Built on theory and insights from the cases, we proposed three propositions. We argued that when co-opetition prevails in a triadic context of relations, the triad resilience level is highest. In competitive relational settings the triad resilience level is lowest, and when the relational dynamics are cooperative, the triad resilience level is moderate. This study is the first to introduce and discuss organisational resilience at triadic level. Furthermore, to our knowledge, our insights from cases are among the first attempts to link three types of supplier–supplier relational dynamics to triad resilience via the use of a multiple-design case approach. Therefore, our contributions are likely to extend the organisational resilience and buyer–supplier–supplier relations research. 相似文献
1000.
AbstractWe present a numerical investigation of an equiangular spiral photonic crystal fibre (ES-PCF) in soft glass for negative flattened dispersion and ultra-high birefringence. An accurate numerical approach based on finite element method is used for the simulation of the proposed structure. It is demonstrated that it is possible to obtain average negative dispersion of –526.99 ps/nm/km over 1.05–1.70 μm wavelength range with dispersion variation of 3.7 ps/nm/km. The proposed ES-PCF also offers high birefringence of 0.0226 at the excitation wavelength of 1.55 μm. The results here show that the idea of using the proposed fibre can be potential means of effectively directing for residual dispersion compensation, fibre sensor design, long distance data transmission system and so forth. 相似文献