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61.
Fisher Lawrence; Soubhi Hassan; Mansi Omaima; Paradis Gilles; Gauvin Lise; Potvin Louise 《Canadian Metallurgical Quarterly》1998,17(4):358
To describe family context in health research, the authors tested a typology of families developed in California with a sample of families in Quebec, Canada. Family scales from the California study were submitted to focus groups, translated, and standardized on a sample of 209 parents. A panel of experts then revised the scales to make them relevant to Quebec families and to health promotion. Data from the new and revised scales were collected on 509 Quebec couples (1,018 spouses) and were clustered separately by gender, using K means. The procedure classified all respondents into family types that paralleled the original typology. Discriminant analyses indicated that family profile variables significantly distinguished family types. Comparisons with family, stress, and health variables further differentiated among the types and expanded their meaning. The study demonstrates a method for redefining and extending family data in health research with different cultural groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
The effectiveness of decision support systems (DSS) is enhanced through dynamic adaptation of support to the needs of the decision maker, to the problem, and to the decision context. We define this enhanced DSS as adaptive decision support systems (ADSS) and propose its architecture. In an ADSS, the decision maker controls the decision process. However, the system monitors the process to match support to the needs. The proposed architecture evolves from the traditional DSS models and includes an additional intelligent‘Adaptation’ component. The ‘Adaptation’ component workd with the data, model, and interface components to provide adaptive support. The architecture also integrates enhancements proposed in the past research. In this paper, we have illustrated the proposed architecture with two examples, a prototype system, and results from a preliminary empirical investigations 相似文献
63.
We have developed an instrument for directly measuring the emissivity of reflective surfaces at near-millimeter wavelengths. The thermal emission of a test sample is compared with that of a reference surface, allowing the emissivity of the sample to be determined without heating. The emissivity of the reference surface is determined by one's heating the reference surface and measuring the increase in emission. The instrument has an absolute accuracy of Δε = 5 × 10(-4) and can reproducibly measure a difference in emissivity as small as Δε = 10(-4) between flat reflective samples. We have used the instrument to measure the emissivity of metal films evaporated on glass and carbon fiber-reinforced plastic composite surfaces. We measure an emissivity of (2.15 ± 0.4) × 10(-3) for gold evaporated on glass and (2.65 ± 0.5) × 10(-3) for aluminum evaporated on carbon fiber-reinforced plastic composite. 相似文献
64.
In this paper, we present curvelet transform (CT) based image steganography that embeds scrambled secret image in appropriately selected cover image. Curvelet transform offers optimal nonadaptive sparse representation of objects with edges and possesses high directional sensitivity and anisotropy. Cover image is decomposed using curvelet transform and adaptive block based embedding is carried out only in non-uniform regions of high frequency curvelet coefficients. In addition, this work also demonstrates a new cover selection method to choose suitable cover from image database. Spatial information based image complexity is modelled using fuzzy logic to identify set of images that yields least detectable stego image. From this set of ranked images, best cover can be chosen for carrying secret information depending on amount of information to be embedded. Cover selection offers reduced risk of detectability and ensures security. It is evident from experimental results that proposed method outperforms conventional methods in terms of imperceptibility, robustness and security. 相似文献
65.
Transferable potentials for phase equilibria. Improved united‐atom description of ethane and ethylene
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Mansi S. Shah J. Ilja Siepmann Michael Tsapatsis 《American Institute of Chemical Engineers》2017,63(11):5098-5110
A more accurate version of the Transferable Potentials for Phase Equilibria—United Atom force field, called TraPPE–UA2, for ethane and ethylene is presented. Very similar molecular volumes, shapes, and self‐ and cross‐interaction strengths of ethane and ethylene make their separation fundamentally interesting and industrially challenging. Separation factors as low as 1.5–3.0 necessitate very accurate molecular models in order to be able to computationally design potential separation processes. Additional force field parameters, namely the distance between the Lennard‐Jones sites for both compounds and partial charges only for ethylene, are introduced in the parameterization and different combining rules for the Lennard‐Jones interaction are considered. In addition to the liquid densities and critical temperature, the training set also includes saturation vapor pressures to yield an accurate two‐site ethane model. Binary ethane/ethylene, CO2/ethylene, and H2O/ethylene vapor–liquid equilibria and H2O/ethylene dimer calculations are used for further optimization of a four‐site ethylene model. © 2017 American Institute of Chemical Engineers AIChE J, 2017 相似文献
66.
Nidhi Parikh Harshal G. Hayatnagarkar Richard J. Beckman Madhav V. Marathe Samarth Swarup 《Autonomous Agents and Multi-Agent Systems》2016,30(6):1148-1174
We describe a large-scale simulation of the aftermath of a hypothetical 10kT improvised nuclear detonation at ground level, near the White House in Washington DC. We take a synthetic information approach, where multiple data sets are combined to construct a synthesized representation of the population of the region with accurate demographics, as well as four infrastructures: transportation, healthcare, communication, and power. In this article, we focus on the model of agents and their behavior, which is represented using the options framework. Six different behavioral options are modeled: household reconstitution, evacuation, healthcare-seeking, worry, shelter-seeking, and aiding & assisting others. Agent decision-making takes into account their health status, information about family members, information about the event, and their local environment. We combine these behavioral options into five different behavior models of increasing complexity and do a number of simulations to compare the models. 相似文献
67.
As-synthesized zeolite ZSM-5 containing the structure-directing agent, tetrapropyl ammonium bromide, when used as a coating material on mild steel substrate material, has been found to offer a promising corrosion resisting results against HCl, HNO3, H3PO4, and H2SO4 of various concentrations at temperatures up to 60 °C under stagnant and stirred conditions. Stable and continuous coated layer is observed under the conditions studied in this work by weight loss and electrochemical methods. Encouraging results in terms of corrosion inhibition efficiency indicate high potential with zeolite (Si/Al ratio 25) material. Material costs compare favorably for zeolite coating against the conventionally used materials. Summarily, zeolite offers an environment-friendly and cost-effective alternate to the other toxic and carcinogenic materials as corrosion-resistant coating. 相似文献
68.
Targeted drug delivery systems are used to minimize the adverse effects of the pharmaceutical agents while maintaining the high local drug concentrations. To minimize post-angioplasty complications like tissue hyperplasia and related restenotic events, cardiovascular stents coated with anti-inflammatory, anti-proliferative agents have been proposed. The efficacy and toxicity of local therapeutics depends upon drug release kinetics which will further decide drug deposition, distribution, and retention at the target site. Drug eluting stents (DES) presently possesses clinical importance as an alternative to coronary artery bypass grafting due to ease of procedure and comparable safety and efficacy. This paper focuses on preparation and evaluation of controlled drug release biodegradable systems for stent base drug delivery providing insight of the drug elution mechanism which ultimately governs release kinetics. Multiple layers of dexamethasone-biodegradable polymers were successfully spray coated on Co–Cr alloy L605 metallic stents by modified air brush technique. In vitro drug elution data acquired by high performance liquid chromatography (HPLC) revealed that release of dexamethasone can be modulated up to 3 weeks by optimized use of blends of biodegradable poly-l-lactide-co-caprolactone and polyvinyl pyrrolidone. Surface investigation by scanning electron microscopy (SEM) represented smooth surface finish without any irregularities suggesting the efficacy of utilization of optimal coating parameters for multiple layer coating. 相似文献
69.
Wireless Networks - With the occurrence of a disaster, the conventional cellular network becomes non-functional. To provide connectivity to the affected users in such a scenario, we propose a novel... 相似文献
70.
Rapid removal of lead(II) ions from water using iron oxide–tea waste nanocomposite – a kinetic study
Mansi Khanna Ashish Mathur Ashwani Kumar Dubey James McLaughlin Igamcha Moirangthem Shikha Wadhwa Devraj Singh Ranjit Kumar 《IET nanobiotechnology / IET》2020,14(4):275
Lead (Pb) ions are a major concern to the environment and human health as they are contemplated cumulative poisons. In this study, facile synthesis of magnetic iron oxide–tea waste nanocomposite is reported for adsorptive removal of lead ions from aqueous solutions and easy magnetic separation of the adsorbent afterwards. The samples were characterised by scanning electron microscopy, Fourier transform‐infrared spectroscopy, X‐ray diffraction, and Braunner–Emmet–Teller nitrogen adsorption study. Adsorptive removal of Pb(II) ions from aqueous solution was followed by ultraviolet–visible (UV–Vis) spectrophotometry. About 95% Pb(II) ion removal is achieved with the magnetic tea waste within 10 min. A coefficient of regression R 2 ≃ 0.99 and adsorption density of 18.83 mg g−1 was found when Pb(II) ions were removed from aqueous solution using magnetic tea waste. The removal of Pb(II) ions follows the pseudo‐second‐order rate kinetics. External mass transfer principally regulates the rate‐limiting phenomena of adsorption of Pb(II) ions on iron oxide–tea waste surface. The results strongly imply that magnetic tea waste has promising potential as an economic and excellent adsorbent for the removal of Pb(II) from water.Inspec keywords: visible spectra, scanning electron microscopy, mass transfer, ultraviolet spectra, X‐ray diffraction, nanocomposites, lead, adsorption, magnetic separation, iron compounds, nanofabrication, Fourier transform infrared spectraOther keywords: FeO, Pb, time 10.0 min, X‐ray diffraction, Fourier transform‐infrared spectroscopy, scanning electron microscopy, adsorbent, magnetic separation, rapid removal, Braunner–Emmet–Teller nitrogen adsorption, iron oxide–tea waste surface, magnetic tea waste, aqueous solution, adsorptive removal, magnetic iron oxide–tea waste nanocomposite, lead(II) ions 相似文献