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181.
Maximum mature larval, cocoon and shell weight were observed during winter season followed by spring and autumn seasons of both white and brick red eri cocoons. Cocoon weight and shell weight were found about 40 and 5%, respectively, as compared to mature larval weight. Degumming loss was estimated at about 10% for white eri and 12% for brick red eri cocoons. Weight of silk fibres varies significantly between layers and decreasing trend was noted from outer to inner layers. Similar trend was observed for single fibre denier and it differs significantly between places (ecoraces), seasons and layers of cocoons. Ascending trend for single fibre tenacity was found from floss to pelade layers of both white and brick red eri silk cocoons and significant influence was observed for places, seasons as well as layers whereas no impact was noted in case of single fibre breaking elongation. Regression equations between weight of degummed cocoon fibres, single fibre denier and single fibre tenacity and to its corresponding values for different places (ecoraces), seasons and cocoon layers were established and estimated R2 and ‘t’ values confirmed the significance of these regression equations.  相似文献   
182.
Photoelectrochemical (PEC) water reduction, converting solar energy into environmentally friendly hydrogen fuel, requires delicate design and synthesis of semiconductors with appropriate bandgaps, suitable energy levels of the frontier orbitals, and high intrinsic charge mobility. In this work, the synthesis of a novel bithiophene‐bridged donor–acceptor‐based 2D sp2‐carbon‐linked conjugated polymer (2D CCP) is demonstrated. The Knoevenagel polymerization between the electron‐accepting building block 2,3,8,9,14,15‐hexa(4‐formylphenyl) diquinoxalino[2,3‐a:2′,3′‐c]phenazine (HATN‐6CHO) and the first electron‐donating linker 2,2′‐([2,2′‐bithiophene]‐5,5′‐diyl)diacetonitrile (ThDAN) provides the 2D CCP‐HATNThDAN (2D CCP‐Th). Compared with the corresponding biphenyl‐bridged 2D CCP‐HATN‐BDAN (2D CCP‐BD), the bithiophene‐based 2D CCP‐Th exhibits a wide light‐harvesting range (up to 674 nm), a optical energy gap (2.04 eV), and highest energy occupied molecular orbital–lowest unoccupied molecular orbital distributions for facilitated charge transfer, which make 2D CCP‐Th a promising candidate for PEC water reduction. As a result, 2D CCP‐Th presents a superb H2‐evolution photocurrent density up to ≈7.9 µA cm?2 at 0 V versus reversible hydrogen electrode, which is superior to the reported 2D covalent organic frameworks and most carbon nitride materials (0.09–6.0 µA cm?2). Density functional theory calculations identify the thiophene units and cyano substituents at the vinylene linkage as active sites for the evolution of H2.  相似文献   
183.
Waterborne polyurethane coatings made from castor oil as polyol resource, replacing oil from fossil fuels are attracting lot of recognition during recent decades. In this review, castor oil and its modifications to synthesize various biobased waterborne polyurethane and their nanocomposite systems have been addressed. Various synthesis procedures for waterborne polyurethane dispersions and their applications as a coating material have been described. This review will be helpful to the green research community for selection of monomer and further development of biobased waterborne polyurethane utilizing advanced technology.  相似文献   
184.
The development of new polymer-based conductive adhesives with specific performances and improved conductivity are increasingly critical for thermally interface material (TIM). Epoxy resins have been widely used as a common interface material for conductive adhesives due to its well-known ability to accept wide range of fillers possibly derived from carbon, metallic or ceramic sources. These conductive fillers with high inherent thermal conductivity, together with a possibility to characterize and manipulate the system, leads to the production of thermally conductive adhesives with higher knowledge content for a number of electronics applications.  相似文献   
185.
In this study, the mono-, bi-, and tri-cultivation of Aureobasidium pullulans, Neurospora crassa, and Trichoderma reesei in solid-state fermentation were applied to improve the nutritional values of hexane extracted canola meal (HECM) along with the reduction of antinutritional factors for animal feed applications. Static fermentation trials of 50% moisture content HECM were conducted in 500 mL Erlenmeyer flasks for 168 hours at 30 °C. The results showed that fungal cultivation had positive effects on the level of protein, fiber, and, glucosinolates (GLS). Monoculture of N. crassa exhibited the highest protein level of 49%. The combination of A. pullulans and N. crassa provided the highest reduction of crude fiber, acid detergent fiber and neutral detergent fiber by 21.9%, 1.7%, and 9.1%, respectively. Bi-culture of A. pullulans and T. reesei resulted in the best GLS reduction by 81.3% (0.3 vs. 1.6 μM g−1 GLS of uninoculated control). These results indicate that each fungal strain possesses different enzymatic ability and selectively can work with other fungi in synergistic relationship for better fungal conversion of canola meal.  相似文献   
186.
Peanut sprouts are gaining increasing popularity as a potential source of functional food. The objective of this study was to investigate yield and food value of peanut sprouts of six Korean peanut genotypes (Daekwang, Akwang, Baekjung, Alogi, Pungan and Heugttangkong) from day 5 through 9. Functional compounds like polyphenol, flavonoid, and resveratrol contents were significantly (p?<?0.05) high in the sprouts compared to those in the seeds. Pungan yielded significantly (p?<?0.05) high sprouts followed by Alogi. However, antioxidant potentials and functional compounds in the sprouts varied significantly (p?<?0.05) with genotype, sprout part, and day after germination. Overall consideration of the yield, functional compounds, and antioxidant potentials of the sprouts suggested that more appropriate time of sprout harvest for Alogi and Pungan was day 5–7 and that for the other genotypes was day 5–8. The yield and functional properties of peanut sprouts significantly varied with genotypes, parts, and age.  相似文献   
187.
A method for preparation of copper nanoparticles (Cu-NPs) was developed by simple reduction of CuCl(2) in the presence of gelatin as a stabilizer and without applying stringent conditions like purging with nitrogen. The NPs were characterized by spectrophotometry, dynamic light scattering, x-ray diffraction, transmission electron microscopy, atomic force microscopy and x-ray photoelectron spectroscopy. The particles were about 50-60?nm in size and highly stable. The antibacterial activity of this Cu-NP on Gram-negative Escherichia coli was demonstrated by the methods of agar plating, flow cytometry and phase contrast microscopy. The minimum inhibitory concentration (3.0?μg?ml(-1)), minimum bactericidal concentration (7.5?μg?ml(-1)) and susceptibility constant (0.92) showed that this Cu-NP is highly effective against E. coli at a much lower concentration than that reported previously. Treatment with Cu-NPs made E. coli cells filamentous. The higher the concentration of Cu-NPs, the greater the population of filamentous cells; average filament size varied from 7 to 20?μm compared to the normal cell size of ~2.5?μm. Both filamentation and killing of cells by Cu-NPs (7.5 μg?ml(-1)) also occurred in an E. coli strain resistant to multiple antibiotics. Moreover, an antibacterial effect of Cu-NPs was also observed in Gram-positive Bacillus subtilis and Staphylococcus aureus, for which the values of minimum inhibitory concentration and minimum bactericidal concentration were close to that for E. coli.  相似文献   
188.
This work provides preliminary data on the effect of torrefaction on the apparent density of biomass. It also examines how the shape of wood is affected by torrefaction. Experiments conducted on cylinders of poplar wood showed that torrefaction reduced both density and volume of the wood, and the extent of reduction increased with increase in severity of torrefaction. The shape of the wood appears to have some effect on the extent of density change. The shrinkage in radial direction was 3–4%, while reduction in longitudinal direction was 6.5–8.8%. The mass yield decreased with torrefaction severity. © 2013 Canadian Society for Chemical Engineering  相似文献   
189.
We, for the first time, employed chemically stable covalent organic framework (COF) (TpPa-1) as a transport-active phase within the polymer (styrene-butadiene rubber; SBR) matrix to make TpPa-1@SBR thin-film composite (TFC) membranes. Three composite membranes, viz., TpPa-1(30)@SBR, TpPa-1(50)@SBR, and TpPa-1(70)@SBR have been prepared with varying COF content. These membranes were characterized for gas permeance and results were compared with the pristine SBR-based TFC membrane. The fully organic nature of chemically stable COF offered good compatibility with the host polymer matrix (SBR) and resulted into flexible TFC membranes even at 70% of COF loading; compared to the other porous material (MOFs or Inorganic fillers), it is appreciable.  相似文献   
190.
Wireless Personal Communications - Non-orthogonal multiple access (NOMA) is one of the promising radio access techniques for resource allocation improvement in the (5th) generation of cellular...  相似文献   
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