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81.
Protease resistant cell-penetrating peptides (CPPs) are promising carriers for drugs unable to cross the cell membrane. As these CPPs are stable in vivo for much longer periods of time compared to other classes of therapeutic peptides, noncytotoxicity is a property sine qua non for their pharmacological development. Described herein is a fully protease resistant CPP that is noncytotoxic at concentrations up to 1 mM. Proteolytic stability was obtained by chiral inversion of the residues of a known self-assembling CPP-from all L-amino acids to all D-amino acids-and then assessed against trypsin and human serum. Circular dichroism studies confirmed the enantiomeric structure of the analogue, and transmission electron microscopy (TEM) studies indicated that the new inverso analogue retains the ability of the original peptide to self-assemble. The results of uptake experiments indicate that the protease-stable (that is, D-amino acid) analogue of the peptide is internalised by cells to the same extent as the protease-susceptible (that is, L-amino acid) parent peptide. Also reported herein are the results of studies on the cellular internalisation mechanism of the all-D analogue, which reveal the steps followed by the peptide upon its entry into the cell.  相似文献   
82.
Gold nanoparticles (AuNPs) of different sizes were synthesized into a crosslinked network of polyacrylamide (PAAm) microgels. PAAm was prepared by means of semicontinuous inverse heterophase polymerization under monomer‐starving conditions with a z‐average particle size of 384 ± 18 nm. AuNPs with controlled size were obtained by a reduction reaction of Au+3 to Au0 from a gold(III) chloride trihydrate (HAuCl4) solution inside microgel the crosslinked network (AuNP‐PAAm). The reduction reaction was verified for 2 h by ultraviolet–visible spectroscopy (UV–vis). AuNP–PAAm exhibited a particle size between 288 ± 12 and 230 ± 15 nm at HAuCl4 concentrations of 0.4 and 1.3 mM, respectively. The AuNP–PAAms were observed by transmission electron microscopy, and their sizes were determined to be 19 ± 2 nm (1.3 mM) and 17 ± 2 nm (1.1 mM). With UV–vis spectroscopy, we detected the formation of AuNPs at a wavelength of 552 nm, and with X‐ray diffraction analysis, we proved that the crystal arrangement was face‐centered cubic. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43560.  相似文献   
83.
Cuenca J  Sobrino JA 《Applied optics》2004,43(23):4598-4602
One condition for precise multiangle algorithms for estimating sea and land surface temperature with the data from the Advanced Along Track Scanning Radiometer is accurate knowledge of the angular variation of surface emissivity in the thermal IR spectrum region. Today there are very few measurements of this variation. The present study is conducted to provide angular emissivity measurements for five representative samples (water, clay, sand, loam, gravel). The measurements are made in one thermal IR broadband (8-13 microm) and three narrower bands (8.2-9.2, 10.3-11.3, and 11.5-12.5 microm) at angles of 0 degrees-60 degrees (at 5 degrees increments) to the surface normal. The results show a general decrease in emissivity with increasing viewing angles, with the 8.2-9.2-microm channel the most sensitive to this dependence and sand the sample showing the greatest variation.  相似文献   
84.
Aerobic biodegradation of diesel fuel (DF)-contaminated wastewater is carried out in a three-phase fluidized bed reactor under unsteady and steady state conditions. The solid phase lava rock particles, which act as the support for the biomass, are fluidized by the upward flows of influent wastewater, and air. The results show that the reactor under unsteady state operation achieved 100% DF removal from synthetic wastewater loaded with 0.43-1.03 kg/m3 day of DF. An average of over 97% of the influent chemical oxygen demand (COD) was also removed from the wastewater with COD concentrations in the range, 547-4025 mg/L. For influent COD concentrations up to 1345 mg/L, the removal is greater than 90%. Under steady state operation, the reactor was able to remove 100% of the DF, and an average of 96% of the COD from the wastewater. It had approximately 200 mg/L of DF, and 1237 mg/L of COD at a low hydraulic residence time of 4 h. In general, the results demonstrate that the reactor is very efficient, and requires short residence times to remove both DF and COD from heavily contaminated wastewater.  相似文献   
85.
Multicast video streaming over multirate wireless LANs imposes strong demands on video codecs and the underlying network. It is not sufficient that only the video codec or only the underlying protocols adapt to changes in the wireless link quality. Research efforts should be applied in both and in a synchronized way. Cross layer design is a new paradigm that addresses this challenge by optimizing communication network architectures across traditional layer boundaries. This paper presents cross-layer architecture for adaptive video multicast streaming over multirate wireless LANs where layer-specific information is passed in both directions, top-down and bottom-up. The authors jointly consider three layers of the protocol stack: the application, data link and physical layers. The authors analyze the performance of the proposed architecture and extensively evaluate it via simulations. The results show that the real-time video quality of the overall system can be greatly improved by cross-layer signaling.  相似文献   
86.
This paper presents an enhanced auto-optimization method to run the 3D-Fast Wavelet Transform on different computing units in a system (GPU, MIC, CPU). The proposed method automatically selects a set of parameter values (block size, number of streams and number of threads) in order to reduce the total execution time, obtaining performances close to the optimal and decreasing the number of evaluations needed.  相似文献   
87.
Fiber-enriched breads can contribute to increasing the daily fiber intake. Resistant starches (RS) are a useful resource to increase the amount of non-digestible carbohydrates while preserving as far as possible the technological quality of white bread. The effects of high concentrations of Hi-Maize (HM), a type 2 RS, in dough formulations were analyzed by farinograph, dynamic rheometric assays, texture profile analysis, and 1H-NMR relaxation measurements and related to particle size and microstructural characteristics studied by different microscopy techniques (SEM, ESEM, CLSM). Up to 30% replacement with HM was performed. Water absorption increased and development time and stability decreased when the amount of HM increased. Water mobility increased suggesting a change in water binding. The mechanical spectra indicated a prevalence of the solid-like character in all samples, but the G′ (storage modulus) vs. G″ (loss modulus) plot suggested a pronounced change in the microstructure of dough at the highest level of replacement. Dough was harder, more adhesive, and less resilient when the HM content was increased. The use of HM in the premix formulations not only diluted the gluten content but also changed the size particle distribution of starch granules by increasing the fraction with smaller sizes. Thus, more compact matrices were obtained with a noticeable disruption of the gluten network at the highest level of replacement. However, an intermediate level of RS addition (20%) still rendered a dough with satisfactory rheological properties for breadmaking.  相似文献   
88.
The present work evaluates the potential of sorghum with high content of tannins for wholegrain flour production. Two types of mills were used: a roller mill (RM) and a blade (BM) mill. The impact of moisture and grinding on yield, physical, chemical and thermal properties were evaluated. Maximum yield was obtained using a BM with 25% moisture in the grain, resulting in 60.9% versus 28% (g flour g−1 of wholegrain sorghum) for the RM. Grain moisture and milling type affected flour colour and ashes. For both mills, the pasting and thermal properties of flour with grain moisture variation were significantly different from the untreated control sample. By studying the procedures for flour production and quality characteristics, it is possible to produce flour with good physical attributes, which can contribute to the development of gluten-free foods based on sorghum for the coeliac population.  相似文献   
89.
A cost effective production of the membrane electrode assemblies (MEA) is a crucial issue for the generation of electricity by proton exchange membrane fuel cells (PEMFC). The deposition of the exact catalyst content on the electrodes in a single printing step is desirable to save processing time and enable cost reduction. In this study, an innovative MEA production process by screen print is developed to produce high performance catalyst layers. The control of the surface tension of the catalyst ink is fundamental to allow the catalyst layer deposition in a single printing step. The electrodes prepared in this way show higher performance than those prepared in several steps. The optimal ink developed shows a viscosity of 2.75 Pa s, a total solid content of 33.76 wt.%, a density of 1.294 g cm−3, and tack value of 92 U.T.  相似文献   
90.
The development of ontologies involves continuous but relatively small modifications. However, existing ontology reasoners do not take advantage of the similarities between different versions of an ontology. In this paper, we propose a collection of techniques for incremental reasoning—that is, reasoning that reuses information obtained from previous versions of an ontology. We have applied our results to incremental classification of OWL ontologies and found significant improvement over regular classification time on a set of real-world ontologies.  相似文献   
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