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161.
Vapour—liquid equilibrium data for the binary systems acetone—benzene, benzene—cyclohexane and acetone—cyclohexane have been determined experimentally at 25°C. The reduction producers based on P - x - y as well as on P - x isothermal data sets, which incorporate usual thermodynamically consistent models expressing the dependence of activity coefficients of liquid composition, have been examined for representing the reported results. Nonideal behaviour of the both phases has been taken into account. Thermodynamic consistency of the data has been shown by comparing of the experimentally obtained vapour compositions with those calculated from P - x data using the best of the examined models for activity coefficients.  相似文献   
162.
The prerequisites for a commercial fermentation process of biosurfactants include the use of low- or negative-cost substrates and maximum conversion yields. Under competitive market conditions, the price of canola oil is expected to decrease in response to its increased supply. Lactose, obtained from cheese whey, is a by-product of the dairy industry. In this work, canola oil with glucose or lactose as carbon sources was used as substrates to produce sophorose lipids (SLs) by means of the yeastCandida bombicola. Fermentations were conducted in either shaker flasks or 1-L Bellco (Vineland, NJ) stirred reactors for 5–7 d at 450 rpm and 30°C. The production of SLs reached 150–160 g/L in a medium consisting of 10% glucose, 10.5% canola oil, 0.1% urea and 0.4% yeast extract. When lactose was substituted for glucose, 90–110 g/L SL was obtained. The apolar SL 17-l-([2′-O-β-d-glucopyranosyl-β-d-glucopyransoyl]oxy)-octadecanoic acid 1′-4″-lactone 6′,6″-diacetate (SL-1) was the major one (73%) when canola oil was used instead of safflower oil (SL-1, 50%). Use of canola oil generally resulted in increased yields of SLs comparable to the yields obtained when safflower oil was used in the medium. Other literature reports present yields of 70 g/L and 120 g/L SLs, respectively, with these substrates.  相似文献   
163.
Customer specific requirements is one of the key drivers in a supply chain strategy based on mass customization. At the same time there are intense pressure on price and short delivery lead times providing a complex environment for managing the supply chain. The complexity can be reduced by introducing the concept of a customer order decoupling point (CODP). The CODP separates the supply chain into two key processes that can be categorized as make-to-order (MTO) and make-to-stock (MTS) and constitutes the two key building blocks of a system based on the mass customization concept. The dynamic properties of the MTS environment have been extensively researched using the automatic pipeline-, inventory-, and order-based production control system (APIOBPCS) archetype. In contrast to MTS systems, the customer facing MTO process, which is usually exposed to a more volatile demand stream suitable for an agile strategy, is less well investigated. Agility does, however, frequently not mean that infinite capacity is available but that there is some surplus capacity available and that the capacity can be adapted to the customer requirements in certain time frames. When the adaptation is not instant but requires some time to take effect the delay creates a dynamic backlog represented by the order book which affects the delivery lead time. Since controlling lead times is a key factor in providing reliable delivery promises an order book control logic is introduced. It is also shown that the new MTO model of the customer facing part of a mass customization system is an extension to the well established APIOBPCS framework  相似文献   
164.
Knowledge discovery in databases is used to discover useful and understandable knowledge from large databases. A process of knowledge discovery consists of two steps, the data mining step and the evaluation step. In this paper, evaluating and ranking the interestingness of summaries generated from databases, which is a part of the second step, is studied using diversity measures. Sixteen previously analyzed diversity measures of interestingness are used along with three not previously considered ones, brought from different well-known areas. The latter three measures are evaluated theoretically according to five principles that a measure must satisfy to be qualified acceptable for ranking summaries. A theoretical correlation study between the eight measures that satisfy all five principles is presented based on mathematical proofs. An empirical evaluation is conducted using three real databases. Then, a classification of the eight measures is deduced. The resulting classification is used to reduce the number of measures to only two, which are the best over all criteria, and that produce non-similar results. This helps the user interpret the most important discovered knowledge in his decision making process.  相似文献   
165.
Nanocrystalline ZnO sponges doped with 5 mol% EuO1.5 are obtained by heating metal–salt complex based precursor pastes at 200–900 °C for 3 min. X-ray diffraction, transmission electron microscopy, and extended X-ray absorption fine structure (EXAFS) show that phase separation into ZnO:Eu and c-Eu2O3 takes place upon heating at 700 °C or higher. The unit cell of the clean oxide made at 600 °C shows only ≈0.4% volume increase versus undoped ZnO, and EXAFS shows a ZnO local structure that is little affected by the Eu-doping and an average Eu3+ ion coordination number of ≈5.2. Comparisons of 23 density functional theory-generated structures having differently sized Eu-oxide clusters embedded in ZnO identify three structures with four or eight Eu atoms as the most energetically favorable. These clusters exhibit the smallest volume increase compared to undoped ZnO and Eu coordination numbers of 5.2–5.5, all in excellent agreement with experimental data. ZnO defect states are crucial for efficient Eu3+ excitation, while c-Eu2O3 phase separation results in loss of the characteristic Eu3+ photoluminescence. The formation of molecule-like Eu-oxide clusters, entrapped in ZnO, proposed here, may help in understanding the nature of the unexpected high doping levels of lanthanide ions in ZnO that occur virtually without significant change in ZnO unit cell dimensions.  相似文献   
166.
Mishra  S. N.  Khan  Abdul Naim  Routray  S.  Jena  K. 《SILICON》2023,15(2):805-812
Silicon - In this work, the authors have demonstrated and differentiated between various analog/RF and linearity performances of a lattice-matched normally off dual-gate ferroelectric metal oxide...  相似文献   
167.
International Journal of Information Security - Malicious websites pose a challenging cybersecurity threat. Traditional tools for detecting malicious websites rely heavily on industry-specific...  相似文献   
168.
Khan  Abdul Naim  Jena  K.  Chatterjee  G.  Routray  S. 《SILICON》2022,14(5):2107-2114
Silicon - In this article, GaN/ InxGa1 − xN based solar cell with Si substrate and SiCN buffer layer is investigated with the help of modeling and simulation. The performance of...  相似文献   
169.
2D Janus transition metal dichalcogenides (TMDs) have attracted attention due to their emergent properties arising from broken mirror symmetry and self-driven polarization fields. While it has been proposed that their vdW superlattices hold the key to achieving superior properties in piezoelectricity and photovoltaic, available synthesis has ultimately limited their realization. Here, the first packed vdW nanoscrolls made from Janus TMDs through a simple one-drop solution technique are reported. The results, including ab initio simulations, show that the Bohr radius difference between the top sulfur and the bottom selenium atoms within Janus M Se S ${\rm{M}}_{{\rm{Se}}}^{\rm{S}}$ (M = Mo, W) results in a permanent compressive surface strain that acts as a nanoscroll formation catalyst after small liquid interaction. Unlike classical 2D layers, the surface strain in Janus TMDs can be engineered from compressive to tensile by placing larger Bohr radius atoms on top ( M S Se ) ${\rm{M}}_{\rm{S}}^{{\rm{Se}}})\ $ to yield inverted C scrolls. Detailed microscopy studies offer the first insights into their morphology and readily formed Moiré lattices. In contrast, spectroscopy and FETs studies establish their excitonic and device properties and highlight significant differences compared to 2D flat Janus TMDs. These results introduce the first polar Janus TMD nanoscrolls and introduce inherent strain-driven scrolling dynamics as a catalyst to create superlattices.  相似文献   
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