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71.
Radiolysis induced adduct products have been separated and identi-fied from irradiated ethyl palmitate, ethyl α-d2-palmitate and ethyl oleate. In the saturated compounds, adduct formation was observed mainly at the position α to the carbonyl group. The three major adduct products identified in irradiated ethyl palmitate were ethyl α-tetradecylpalmitate, ethyl α-pentadecylpalmitate and the α,α′- dimer of ethyl palmitate. Corresponding compounds were identified from the irradiated ethyl α-deuteropalmitate. Adduct radiolysis products formed in ethyl oleate were identified as the monoene and diene dimers.  相似文献   
72.
Abstract:

Complex investment decisions by corporate executives often require the comparison of dissimilar attributes and competing technologies. A technique to evaluate qualitative input from experts using a multi-criteria decision making (MCDM) method is described to select a new reactor technology for a merchant nuclear generator. The capital cost, risks from design, licensing and construction, reactor safety, and security considerations are some of the diverse considerations when choosing a reactor design. The uncertainty inherent in experts' opinions for the attribute weighting in the MCDM is modeled through the use of probabilistic inversion. After creating a distribution, random samples from the distribution are used to analyze the “strength” of the results. The decision results for the pool of experts identified the U.S. EPR as their optimal choice.  相似文献   
73.
74.
Bulk graphene was prepared by the method of magnesium combustion in a CO2 atmosphere, producing large quantities of material which had a different morphology and importantly, a more ordered carbon lattice than reduced graphene oxide and other bulk graphene synthetic methodologies. Despite a low surface area of 235.5 m2/g and ca 9 at.% of magnesium and its oxides which do not contribute to hydrogen adsorption, we observe 0.85 wt.% of H2 at 65 bar and 77 K, and 0.9 wt.% of H2 at 300 bar and 293 K. As this methodology readily produces many-gram quantities with cheap starting materials, we anticipate that with further enhancements to the synthetic methodology, improving both surface area and reducing reaction by-products, this material will provide a robust platform for further H2 adsorption investigations.  相似文献   
75.
Yeast growth is increased and the initial rate of fermentation is accelerated by the residue of insoluble material which is normally present in distiller's malt wort. The increase in yeast concentration is accompanied by a high glycerol content in the fermented liquor and the formation of higher alcohols, particularly isobutanol and 2-methyl butanol, is also increased. The stimulation of yeast growth is independent of the state of aeration of the wort, suggesting that the effect is not associated with entrainment of oxygen by the solids, and the chemical nature and particle size of the suspended material do not appear to be important. Insoluble solids were without effect when yeast growth was limited by carbohydrate rather than by amino-nitrogen. The results suggest that a combination of electrostatic and absorption forces concentrate yeast cells and amino acids at the solid-liquid interface, increasing the rate of uptake of nutrients by the cell and thus diverting carbohydrate to processes associated with yeast growth.  相似文献   
76.
Studies have been carried out on the compatibilization of polypropylene and nylon using maleic anhydride grafted polypropylene (Polybond? 3002). Solution and FTIR studies on the resin indicated that the compatibilizer reacted with nylon. The usefulness of the compatibilizer has been demonstrated for the recycling of shredded industrial carpet waste containing polypropylene and nylon. The mechanical properties and morphology of the extruded resin from carpet are reported.  相似文献   
77.
The goal of the Plasma Liner Experiment (PLX) is to explore and demonstrate the feasibility of forming imploding spherical "plasma liners" via merging high Mach number plasma jets to reach peak liner pressures of ~0.1?Mbar using ~1.5?MJ of initial stored energy. Such a system would provide HED plasmas for a variety of fundamental HEDLP, laboratory astrophysics, and materials science studies, as well as a platform for experimental validation of rad-hydro and rad-MHD simulations. It could also prove attractive as a potential standoff driver for magnetoinertial fusion. Predicted parameters from jet formation to liner stagnation cover a large range of plasma density and temperature, varying from n(i)~10(16)?cm(-3), T(e)≈T(i)~1?eV at the plasma gun mouth to n(i)>10(19)?cm(-3), T(e)≈T(i)~0.5?keV at stagnation. This presents a challenging problem for the plasma diagnostics suite which will be discussed.  相似文献   
78.
Debates surrounding the greenhouse gas (GHG) emissions from land use of biofuels production have created a need to quantify the relative land use GHG intensity of fossil fuels. When contrasting land use GHG intensity of fossil fuel and biofuel production, it is the energy yield that greatly distinguishes the two. Although emissions released from land disturbed by fossil fuels can be comparable or higher than biofuels, the energy yield of oil production is typically 2-3 orders of magnitude higher, (0.33-2.6, 0.61-1.2, and 2.2 5.1 PJ/ha) for conventional oil production, oil sands surface mining, and in situ production, respectively). We found that land use contributes small portions of GHGs to life cycle emissions of California crude and in situ oil sands production ( <0.4% or < 0.4 gCO?e/MJ crude refinery feedstock) and small to modest portions for Alberta conventional oil (0.1-4% or 0.1-3.4 gCO?e/MJ) and surface mining of oil sands (0.9-11% or 0.8-10.2 gCO?e/MJ).Our estimates are based on assumptions aggregated over large spatial and temporal scales and assuming 100% reclamation. Values on finer spatial and temporal scales that are relevant to policy targets need to account for site-specific information, the baseline natural and anthropogenic disturbance.  相似文献   
79.
A new general theory about restoration of network paths is first introduced. The theory pertains to restoration of shortest paths in a network following failure, e.g., we prove that a shortest path in a network after removing k edges is the concatenation of at most k+1 shortest paths in the original network. The theory is then combined with efficient path concatenation techniques in MPLS (multi-protocol label switching), to achieve powerful schemes for restoration in MPLS based networks. We thus transform MPLS into a flexible and robust method for forwarding packets in a network. Finally, the different schemes suggested are evaluated experimentally on three large networks (a large ISP, the AS graph of the Internet, and the full Internet topology). These experiments demonstrate that the restoration schemes perform well in actual topologies. Received: December 2001 / Accepted: July 2002 RID="*" ID="*" This research was supported by a grant from the Ministry of Science, Israel  相似文献   
80.
The Ethical Principles exhort psychologists "to encourage ethical behavior by students, supervisees, employees, and colleagues, as appropriate" (American Psychological Association, 1992, p. 1599). In spite of a clear directive to attempt resolution of unethical conduct by colleagues, research indicates that satisfactory resolution or actual reporting of misconduct is infrequent. This paper will address some of the forces that discourage psychologists from dealing responsibly and appropriately with professional misconduct by colleagues. The goals of this paper are to promote understanding of factors that interfere with the effective resolution of ethical misconduct, to identify possible signs of reluctance to address misconduct, and to propose strategies to combat those forces that keep us in silent collusion with colleagues who engage in unethical practices. A flowchart of steps for addressing possible misconduct by a colleague is provided, and educational, organizational, and professional considerations are discussed.  相似文献   
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