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51.
Reliable broadband communication is becoming increasingly important during disaster recovery and emergency response operations. In situations where infrastructure-based communication is not available or has been disrupted, an Incident Area Network needs to be dynamically deployed, i.e. a temporary network that provides communication services for efficient crisis management at an incident site. Wireless Mesh Networks (WMNs) are multi-hop wireless networks with self-healing and self-configuring capabilities. These features, combined with the ability to provide wireless broadband connectivity at a comparably low cost, make WMNs a promising technology for incident management communications. This paper specifically focuses on hybrid WMNs, which allow both mobile client devices as well as dedicated infrastructure nodes to form the network and provide routing and forwarding functionality. Hybrid WMNs are the most generic and most flexible type of mesh networks and are ideally suited to meet the requirements of incident area communications. However, current wireless mesh and ad-hoc routing protocols do not perform well in hybrid WMN, and are not able to establish stable and high throughput communication paths. One of the key reasons for this is their inability to exploit the typical high degree of heterogeneity in hybrid WMNs. SafeMesh, the routing protocol presented in this paper, addresses the limitations of current mesh and ad-hoc routing protocols in the context of hybrid WMNs. SafeMesh is based on the well-known AODV routing protocol, and implements a number of modifications and extensions that significantly improve its performance in hybrid WMNs. This is demonstrated via an extensive set of simulation results. We further show the practicality of the protocol through a prototype implementation and provide performance results obtained from a small-scale testbed deployment.  相似文献   
52.
The aim of this investigation was to analyse the composition of dietary fibre from aronia pomace preparations and to evaluate its influence on cadmium and magnesium binding. The authors wanted also to estimate to what extent additional enzymatic processing could affect the sorption capacity of the aronia fibre.  相似文献   
53.
Pressure drop dependences on gas and solid flow rates and solid concentrations for a vertical pipe section and for a conical—cylindrical—conical chamber have been determined. Equations for a particle—wall friction factor have been obtained. Values of particle—wall friction factor for a vertical pipe section are in reasonable agreement with literature data. For a conical—cylindrical—conial chamber friction factors can be both positive and negative.  相似文献   
54.
Absorption of SO2 and SO3 in the solutions of waste ferrous sulfate (so-called ‘green salt’) and in the spent acid after TiO2 hydrolysis, at H2SO4 concentrations ranging from 0–5 to 15 g/m3 (STP), was studied. The rate of SO3 absorption has been found to rise linearly with increasing SO3 concentration in the gas and to be independent on H2SO4 concentration in solution. The SO2 absorption also rises linearly with increasing SO2 content in the gas, but diminishes as H2SO4 concentration increases—an upper limit of 100 g H2SO4/kg H2O is indicated. The initial concentration of the solution must not be higher than 40 g H2SO4/kg H2O.  相似文献   
55.
Abstract

This publication presents the research results concerning determination of the level of landscape attractiveness of the abandoned quarries. The research focused upon 20 structures located within the area of Poland, Great Britain and Austria. The research used procedures of landscape attractiveness assessment which features three research methods: survey method with the use of the semantic differential, the method of point bonitation and the landscape entropy method. Throughout the analysis conducted, the level of landscape attractiveness of the quarries was determined according to four classification groups: very attractive quarry landscape (I), attractive quarry landscape (II), little attractive quarry landscape (III) and unattractive quarry landscape (IV).  相似文献   
56.
Research on water scarcity and water management in Europe has accelerated significantly in the past two decades, mainly as a result of growing water demand for agricultural, industrial, and municipal uses. Most research studies in the field evaluate water use and management by means of static indicators that depict a one-time value for a given time period (e.g., one year). This paper suggests a dynamic indicator measuring product (here: water) generational dematerialization. The indicator presents a comprehensive approach for evaluating water resources and water management strategies, as it represents a function of both resource use changes and population changes occurring simultaneously and over time. To accentuate the benefits of this dynamic indicator over static indicators as well as its practical applicability for decision-making support, the paper evaluates water management in Europe based on the total water use between 2001 and 2013. The results show that water management estimated cumulatively for the analyzed European countries has been effective for the last 13 years, though significant regional variations have been found. The research and the dynamic water generational dematerialization indicator can be helpful with addressing regional and national water deficit problems and designing sustainable water management strategies in the mid- and long-run.  相似文献   
57.
An effective two-stage method for obtaining polyacrylonitrile fibers with antibacterial properties has been developed. The method consists of the incorporation of carboxylic groups into fibers by PAA grafting polymerization followed by fiber impregnation with gentamycin, neomycin, or penicillin solutions. The modified fibers show effective biocide liberation into water and antibacterial activity towards Gram-positive and Gram-negative microorganisms (Staphylococuus aureus, Escherichia coli, and Pseudomonas aeruginosa). The presence of antibiotics combined with the modified fibers though chemical bonds has been proved by IR and 1H-NMR investigations. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65: 1955–1966, 1997  相似文献   
58.
The objective of this article was to determine the structure of microbial communities and the activity of dehydrogenases in soil samples contaminated with four polycyclic aromatic hydrocarbons (PAHs), i.e., naphthalene, phenanthrene, anthracene, and pyrene, in the amount of 0, 1000, 2000, and 4000 mg kg?1soil DM. Organic substances—cellulose, sucrose, and compost—were added to the samples in the amount of 0 and 9 g kg?1soil DM. The experiment was performed in a laboratory on samples of loamy sand. Indices of colony development (CD) and eco-physiological diversity (EP) of organotrophic bacteria, soil resistance (RS), and soil resilience (RL) were calculated. Soil contamination with PAHs differentiated the structure of organotrophic bacteria, and the lowest CD and EP values were noted in soil samples containing pyrene. PAHs inhibited the activity of dehydrogenases, and pyrene exerted the most inhibitory effect on enzyme activity. Dehydrogenase activity was determined mainly by the applied PAH dose, the date of analysis and the type of organic substance added to soil. Low RL values indicate that exposure to PAHs induces long-term changes in dehydrogenase activity.  相似文献   
59.
It was established that the synthesis of hybrid molecules containing a thiazolidinone and a (2Z)-2-chloro-3-(4-nitrophenyl)prop-2-ene structural fragments is an effective approach for the design of potential anticancer agents. Given the results of the previous SAR-analysis, the aim of the study was to synthesize a novel 4-thiazolidinone derivative Les-3331 and investigate its molecular mechanism of action in MCF-7 and MDA-MB-231 breast cancer cells. The cytotoxic properties and antiproliferative potential of Les-3331 were determined. The effect of the tested compound on apoptosis induction and mitochondrial membrane potential was checked by flow cytometry. ELISA was used to determine caspase-8 and caspase-9, LC3A, LC3B, Beclin-1, and topoisomerase II concentration. Additionally, PAMPA, in silico or in vitro prediction of metabolism, CYP3A4/2D6 inhibition, and an Ames test were performed. Les-3331 possesses high cytotoxic and antiproliferative activity in MCF-7 and MDA-MB-231 breast cancer cells. Its molecular mechanism of action is associated with apoptosis induction, decreased mitochondrial membrane potential, and increased caspase-9 and caspase-8 concentrations. Les-3331 decreased LC3A, LC3B, and Beclin-1 concentration in tested cell lines. Topoisomerase II concentration was also lowered. The most probable metabolic pathways and no DDIs risk of Les-3331 were confirmed in in vitro assays. Our studies confirmed that a novel 4-thiazolidinone derivative represents promising anti-breast cancer activity.  相似文献   
60.
The binding extent of odorant mixtures from aqueous suspensions by native, high pressure-treated starches and starch cryotexturizates was studied using capillary gas chromatography. The materials were corn, sorghum and amaranth starches. The native and high pressure-treated (650 MPa/9 min) starches were mixed with odorants and incubated (24 h) at room temperature. To obtain the cryotexturizate-odorant product, starch gels were frozen with odorants (−24 °C), stored (48 h) and thawed. Terpene hydrocarbons were strongly bound from the mixture by all the starches analyzed. The nonpolar molecules of terpene hydrocarbons modified the nature of hydrophobic binding sites in starch which in turn affected binding affinity of alcohols, ketones and phenols to the preparations. The competition effect between odorants for the binding sites was found. The varied ability of starch preparations to bind odorants was also related to the granule morphology and alteration in their structure upon treatment used.  相似文献   
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