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621.
622.
Dynamic conductivity measurements proved to be an effective and rapid method to determine the optimal experimental conditions for a salinity-induced phase-inversion from surfactant/oil/water (SOW) systems consisting of nonionic surfactants, more specifically alcohol ethoxylates. This emerging methodology can be used as a rapid screening tool to determine the impact of alcohol ethoxylate surfactants in a SOW solution and was demonstrated to be not only repeatable, but highly comparable to the traditional static method, in which the solutions are added to flat bottom tubes and allowed to equilibrate at a given temperature for extended time periods. Given a set of experimental conditions (oil-type, temperature, etc.), these dynamic salinity-induced phase-inversion (Dy-SPI) conductivity measurements can be used to determine the optimal salinity (S*) for a given surfactant at a set concentration, as well as its characteristic curvature via a series of experiments with varying oil types. Additionally, Dy-SPI was used to confirm the previously observed inverse relationship between the concentration of an alcohol ethoxylate and S* under a given set of conditions. What makes this method so unique is the amount of time (30 min to 1 h) and the simplicity of the equipment needed for these Dy-SPI conductivity measurements, allowing for a rapid screening tool for these SOW parameters.  相似文献   
623.
Copaiba oleoresin has sesquiterpenes and diterpenes with significant medicinal properties, including being antimicrobial, antiparasitic, and wound healing, among others. Thus, the objective of this work was to study the diterpene enrichment of the copaiba oleoresin from Copaifera officinalis via molecular distillation. Evaporator temperature (EVT) and feed flow rate (Q) were evaluated using an experimental design (22 with central point) considering the ratio of distillate and residue streams (DTR) as the response to optimize the residue recovery. EVT and Q were the main effects for diterpenes recovery, with the best experimental condition at 100°C (EVT) and 15 ml/min (Q) under 0.001 mbar, of which the residue stream had a diterpenes content of 99.25%. With the molecular distillation process, it was possible to add value to the copaiba streams, separating and purifying diterpenes with applicability in the biomedical and pharmaceutical industries since no solvent is used in this process (clean).  相似文献   
624.
An in silico study focused on known cancer-related target proteins, identified a selection of imidazo[4,5-b]pyrrolo[3,4-d]pyridines as potentially active. These compounds were prepared by a novel synthetic approach, designed and developed in-house, based on the reaction of 5-amino-4-cyanoformimidoyl imidazoles with N-substituted cyanoacetamides. The substituted imidazolylpyrrolones obtained, were cyclized intramolecularly to generate the intended imidazo[4,5-b]pyrrolo[3,4-d]pyridines in a process catalyzed by DBU. Treating the imidazolylpyrrolones with an excess of triethyl orthoformate and heating at 80 °C in the presence of acid catalysis led to imidazopyrrolodiazepines. These compounds were screened for their anticancer potential, using the renal cell carcinoma cell line model (A498 and 786-O cell lines). Two compounds exhibited IC50 values in the low micromolar range with a good selectivity index, when compared to non-neoplastic kidney cell line HK2 and the reference compounds rapamycin, cediranib and sunitinib.  相似文献   
625.
Green infrastructure has been increasingly identified as an option to help manage climate change impacts in urban areas, although its implementation is still not widely promoted in urban planning. This is because of the lack of detailed analysis for decision-makers regarding construction and maintenance costs for different types and how effective various measures are at managing precipitation at a catchment scale. This paper contributes to fill this gap in knowledge by developing a green infrastructure cost-effectiveness ranking index (GICRI) able to evaluate the stormwater runoff volume reduction of multiple green infrastructure alternatives under different climate change scenarios, over differing spatial configurations and combining this performance data with their construction and maintenance costs. After applying this model over two case study areas, this paper provides three main insights. First, climate change projections have a significant impact on green infrastructure cost-effectiveness. Second, as green infrastructure cost-effectiveness is influenced by the spatial scale, there are different challenges for larger cities and smaller regional towns. Building on this, the paper argues that GICRI can be a simple and fast heuristic to increase the use of green infrastructure by informing decision-makers regarding how and where to prioritize investment or where greater modelling is needed.  相似文献   
626.
The implementation rate of renewable energy sources such as lithium-ion batteries has grown over the last decade. Consequently, the number of explosion occurrences associated with these batteries has also increased. Such events are due to a process called thermal runaway (TR). The flamelet combustion approach has been widely used to model premixed combustion. However, its applicability for modelling accidental explosions from lithium-ion batteries remains limited. Moreover, the effects and contributions from stress, strain, and wrinkling on the flame front in gas mixtures from Li-ion batteries are not fully understood. As far as computational modelling is concerned, the same effects require further investigation. The current research investigates the performance of the flamelet approach for modelling premixed combustion scenarios caused by the gases ejected by a fully charged lithium-ion-phosphate (LFP) battery. A new laminar burning velocity correlation is proposed based on experimental data to calculate overpressure, flame position, and flame velocity in a semi-confined geometry. Promising results are presented resorted by good agreement with experimental data.  相似文献   
627.
The aim of this study was to prepare active, biodegradable methylcellulose films and evaluate their properties after incorporating cinnamon (Cinnamomum cassia) and litsea cubeba (Litsea cubeba) essential oils. The properties of the methylcellulose films were modified with the addition of essential oils. The surfaces were smooth and homogeneous in all samples. The film with cinnamon oil showed higher antibacterial activity against Staphylococcus aureus and Escherichia coli and the film with litsea cubeba showed higher antioxidant activity against ABTS radical. The biodegradation time of the films in black sand and beach soil was 20 days. The films produced that presented the highest potential to become active packaging were the film with litsea cubabe oil as antioxidant packaging and the film with cinnamon oil as antibacterial packaging.  相似文献   
628.
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