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11.
By adsorbing bovine serum albumin (BSA) on gold nanoparticles (Aunps) with diameters 30 nm and 80 nm, different degrees of protein unfolding were obtained. Adsorption and adlayer conformation were characterized by UV-vis spectroscopy, ζ-potential measurements, steady-state and time-resolved fluorescence. The unfolding was also studied using 1-anilino-8-naphthalene sulfonate (ANS) as an extrinsic probe, showing that BSA unfolds more on 80 nm Aunp than on 30 nm Aunp. Langmuir monolayer studies using two distinct methods of introducing the BSA and BSA-Aunp constructs accompanied with Brewster Angle Microscopy (BAM) and Digital Video Microscope (DVM) imaging demonstrated that BSA-Aunp constructs induce film miscibility with L-α-phosphatidylethanolamine not seen for BSA or Aunp alone. The changes induced by partial unfolding clearly give better film-penetration ability, as well as disruption of liquid crystalline domains in the film, thereby inducing film miscibility. Gold or protein only does not possess the nanoscale film-affecting properties of the protein-gold constructs, and as such the surface-active and miscibility-affecting characteristics of the BSA-Aunp represent emergent qualities.  相似文献   
12.
The stability of dye dispersions in the presence of ethoxylated sorbitan lauryl and oleyl esters were reported and compared with dye dispersions containing a conventional dispersing agent, i.e. naphthalene sulfonic acid methylene-bis sodium salt (NSAB). The optimum operating conditions obtained using a central composite design and stability of dye dispersions were evaluated by a turbidimetry method. Results showed that the dose of surfactants and the temperature of operation were important factors in preparing stable dye dispersions. Also, the best conditions for preparing dye dispersions were as follows: dose of surfactant 0.05 g, temperature 25 °C and time 5 min. In addition to, findings indicated that both of the used surfactants had better performance in dispersing the dyes in water. However, ethoxylated sorbitan oleate had better efficiency relative to other used dispersing agents. The performance of both sorbitan esters were compared with NSAB. The results indicated that they can create stable dye dispersions in aqueous media and have approximately the same effectiveness with NSAB. In this series, although oleate ester had a better performance than the laurate, the difference in performance of using dispersing agents was not significant. This finding was confirmed by the results of the particle size analysis of dye dispersions.  相似文献   
13.
Definition of the problem The development of personalized medicine is currently a popular topic. Particularly the personalized pharmacotherapy is a matter of relative importance due to pharmacological and molecular–genetic developments. For this reason it is required to examine the implications of personalized pharmacotherapy to statutory health insurance and health care of patients. Arguments In this context the question of orphanization arises: If medical drugs of personalized medicine could be regularly indicated as orphan drugs, i.e., as drugs to medicate orphan diseases, it would not be necessary according to the “Arzneimittelneuordnungsgesetz” (AMNOG) to prove an auxiliary value within the assessment of the “Gemeinsamer Bundesausschuss” (GBA). Crucial to the drug’s indication as an orphan drug is among other things the rate of prevalence of the patient group, whose disease should be medicated with the drug. In this connection, there is importance attached to the stratification of patient groups within personalized medicine. Conclusion An orphanization causes consequences in terms of prices to the statutory health insurance due to the lack of knowledge about an auxiliary value. For patients, the implications must be considered in a more differentiated manner.  相似文献   
14.
The aim of this project was to check reproducibility of results obtained using NOCS (no connection to the substrate) arrangement of the electrochemical noise method (ENM). NOCS involves taking measurements from three nominally identical areas on the coated surface. Thus, no electrical connection to substrate is required. In practice the areas are not identical and various arrangements for connection of the three cells were tried to see if the individual areas could be separated out and whether the individual resistances could be computed. Also different ways of calculating the Rn (noise resistance) and Rsn (spectral noise resistance) parameters were attempted to see which one gave the best comparison with the more standard EIS measurements. The maximum entropy method was recognized to be the most useful for comparison with EIS, as well as for graphic evaluation of results. Regarding distinguishing three areas using different connection arrangements, it was possible to identify the situation when one of the three values was different to the other two. However further experiments are needed before it will be possible to confidently assign an Rn value to each individual area.  相似文献   
15.
ABSTRACT

Cadmium as a highly toxic metal is released into the environment through paper production, metal processing, phosphate fertilizers, insecticides, and treatment of wastewater. Cadmium also inhibits the body activities and is very toxic for kidney and other organisms. In the current study, zinc-based metal–organic framework, zeolitic imidazolate framework (ZIF)-8, was synthesized and modified by dimethylethylenediamine (ZIF-8-mmen) for the removal of cadmium. To optimize the experiments, response surface methodology was applied with three variables including pH, adsorbent dosage, and contact time using central composite design. The optimum conditions for pH, dosage, and time were 2, 0.1 g, and 89 min, respectively, with removal efficiency of 85.38%. The Langmuir isotherm (q m = 1000 mg/g) indicates the monolayer adsorption. The kinetic studies reveal that the Lagergren model was predominant and cadmium was not chemisorbed. Thermodynamic parameters show spontaneous, endothermic, and physisorption processes.  相似文献   
16.
We studied the adsorption of SOx (x?=?2,3) molecules on the surface of pristine graphene (PG) and N-doped graphene (NDG) by density functional theory (DFT) calculations at the B3LYP/6-31G(d) level. We used Mulliken and NBO charge analysis to calculate the net charge transfer of adsorbed SOx on pristine and defected graphene systems. Our calculations reveal much higher adsorption energy and higher net charge transfer by using NDG instead of pristine graphene. Furthermore, the density of state (DOS) graphs point to major orbital hybridization between the SOx and NDG, while there is no evidence of hybridization by using pristine graphene. Based on our results, it is found that SO2 and SO3 molecules can be adsorbed on the surface of NDG physically and chemically with adsorption energies (Eads) of ?27.5 and 65.2?kJ?mol?1 (19.6 and 51.4?kJ?mol?1 BSSE), respectively, while low adsorption energies were calculated in the case of using pristine graphene. So we introduced NDG as a sensitive adsorbent/sensor for detection of SO2 and SO3.  相似文献   
17.
Thermally induced torsional and tensile actuators based on twisted polymeric fibers have opened new opportunities for the application of artificial muscles. These newly developed actuators show significant torsional deformations when subjected to temperature changes, and this torsional actuation is the defining mechanism for tensile actuation of twisted and coiled fibers. To date it has been found that these actuators require multiple heat/cool cycles (referred to as “training” cycles) prior to obtaining a fully reversible actuation response. Herein, the effect of annealing conditions applied to twisted nylon 6 monofilament is investigated and it is shown that annealing at 200 °C eliminates the need for the training cycles. Furthermore, the effect of an applied external torque on the torsional actuation is also investigated and torsional creep is shown to be affected by the temperature and load. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45529.  相似文献   
18.
Reactive plasma spray of TiN ceramic coating attracts much attention over the years because of its ability to deposit thick layers on various metal surfaces. However, some mechanical properties of the coating such as its hardness should be improved. In this study, initially a thin layer of titanium nitride was prepared on a titanium substrate during irradiation of titanium substrate by a thermal DC nitrogen-contained plasma jet. Then, during reactive plasma spraying, Ti particles were injected into plasma jet, converted to titanium nitride and huddled on to the substrate. This new hybrid method (primary plasma irradiation and post-reactive plasma spraying) for deposition of TiN coatings would combine the advantages of both plasma-enhanced chemical vapor deposition and reactive plasma spraying methods in part. It resulted in a thick and hard layer of titanium nitride film. Sample produced by this method was analyzed with x-ray diffraction confirming titanium nitride production. Vickers hardness was measured using optical microscopy which was around 1319 Hv300g. To study the cross section of the layer, optical microscopy and scanning electron microscopy (SEM) were used.  相似文献   
19.
Carbohydrate-based vinyl acetals (5-hex-enopyranosides) undergo reductive rearrangement with triisobutylaluminum (TIBAL) to afford highly functionalized cyclohexanes in which both the aglycon and anomeric stereochemistry are retained. Here, we report the first application of this process to the rearrangement of hex-5-enopyranosides of sucrose in which the interglycosidic oxygen atom of the vinyl acetal system links the anomeric centers of both monosaccharide units. The sucrose-derived 5-hex-enopyranoside 1 undergoes smooth reductive rearrangement with TIBAL to afford the (1 → 2′) ether-linked pseudo-disaccharide 2 in 34% yield. The rearrangement is accompanied by some loss of stereochemical integrity at C-2′ due to a competitive exo-cleavage of the interglycosidic (O-C2′) bond, hence diastereomers at C-2′ are also obtained in 12% yield. The 4-O-allyl-protected sucrose-5-ene 3 is similarly transformed into the corresponding (1 → 2′) ether-linked pseudo-disaccharide 4 , illustrating the compatibility of the allyl group with the TIBAL reaction conditions.   相似文献   
20.
The techno-economic evaluation of four novel integrated gasification combined cycle (IGCC) power plants fuelled with low rank lignite coal with CO2 capture facility has been investigated using ECLIPSE process simulator. The performance of the proposed plants was compared with two conventional IGCC plants with and without CO2 capture. The proposed plants include an advanced CO2 capturing process based on the Absorption Enhanced Reforming (AER) reaction and the regeneration of sorbent materials avoiding the need for sulphur removal component, shift reactor and/or a high temperature gas cleaning process. The results show that the proposed CO2 capture plants efficiencies were 18.5–21% higher than the conventional IGCC CO2 capture plant. For the proposed plants, the CO2 capture efficiencies were found to be within 95.8–97%. The CO2 capture efficiency for the conventional IGCC plant was 87.7%. The specific investment costs for the proposed plants were between 1207 and 1479 €/kWe and 1620 €/kWe and 1134 €/kWe for the conventional plants with and without CO2 capture respectively. Overall the proposed IGCC plants are cleaner, more efficient and produce electricity at cheaper price than the conventional IGCC process.  相似文献   
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