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161.
We present the design, synthesis, and characterization of a novel photocaged glutamine derivative (modified on the side chain of glutamine), and describe its use in enhancing peptide stability and solubility. Our results demonstrate that this approach can be used to develop molecular switches to control the folding and β‐sheet formation of amyloidogenic peptides.  相似文献   
162.
Five different hydrocolloids (tragacanth gum, guar gum, carboxy methyl cellulose, xanthan gum and locust bean gum) were added, at levels of 0, 0.5, and 1 g/100 g (w/w), respectively, to three different formulated ketchups which were processed from cold-break tomato paste dilutions, having total soluble solid (TSS) contents of 7.5, 10, and 12.5 g/100 g (w/w), in sequence, and the effect of these hydrocolloids on the rheological properties of tomato ketchups was investigated using a viscometer with smooth surface wide-gap coaxial cylinders. All hydrocolloids increased the consistency of the tested samples; however, guar gum and locust bean gum caused the maximum increase, followed by xanthan gum, tragacanth gum and carboxy methyl cellulose (CMC). Both the ketchup formulation and the hydrocolloid concentration were found to affect the consistency of ketchups. The highest consistency index was obtained by processing dilutions with a TSS content of 12.5%, and the addition of hydrocolloids at the level of 1%. The fluidity of the ketchups decreased with both the addition of all hydrocolloids and the increase in hydrocolloids concentration. Furthermore, the fluidity of the ketchups was also affected by ketchup formulation, and it was found to be the lowest for the samples prepared from the tomato paste dilutions having a TSS content of 12.5%.  相似文献   
163.
In this study; the effects of loop, skip, and tuck stitch types, and weft-inlay yarn, on air permeability and bursting strength of weft-knitted fabrics from glass yarn were revealed. Due to clockwise rotation of wales and their arrangement being one on top of the other, besides the dramatic shortening of fabrics after their removal from the machine; fabrics with tuck stitches exhibited the highest stitch density, fiber content, and the shortest loop length. This caused the lowest air permeability and the highest bursting strength. Contrary to expectations, weft-inlay yarn did not contribute to bursting strength as much as tuck stitch did. An overall negative correlation between air permeability and bursting strength was disrupted by structures with tuck stitches. While tuck stitches from cotton yarn increased air permeability and decreased bursting strength in previous studies; this study indicated that tuck stitches from glass yarn decreased air permeability and increased bursting strength.  相似文献   
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166.
Glass beads (GB) immobilized, 5,11,17,23-tetra-tert-butyl-25,27-diethoxycarbonylmethoxy-26,28-dihydroxycalix[4]arene (CA) are prepared and used as a new sorbent in sorption study of removal heavy metal ions. A calixarene derivative bonded to amino-functionalized glass beads sorbent was synthesized via a self assembly technique for sorbent of selected heavy metal ions in aqueous. In order to absorb selected heavy metal ions in aqueous, a calixarene derivative bonded to amino-functionalized glass beads sorbent was synthesized via a self assembly technique. The sorbent which is named GB-APTS-CA was characterized using infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), elemental analysis and thermal analysis (TGA/DTG). The influences of some experimental parameters including pH of the sample solution, weight of sorbent, concentration and temperature have been investigated. The sorption data were evaluated using the Langmuir, Freundlich and Dubinin Radushkevich (D-R) isotherm. The obtained maximum sorption capacity for Cu(II), and Pb(II) is 0.06 mmol g?1 and 0.02 mmol g?1, respectively. Thermodynamic parameters such as the standard free energy change (ΔG○), enthalpy change (ΔH○) and entropy change (ΔS○) were calculated to determine the nature of sorption process. Thus, GB-APTS-CA is favorable and useful for the removal of Cu(II) and Pb(II) metal ions.  相似文献   
167.
The interfacial kinetics of charge transfer at n-GaAs/liquid junctions were controlled by anchoring positively charged species, such as tetra(-4-pyridyl)porphyrinatomanganese(III), with the semiconductor surface. Unlike earlier adsorption techniques, the charges have been chemically anchored to the semiconductor surface, in this work, via a ligand. The number of charges per site (attached molecule) ranged from +1 to +5. The positive charges shifted the band-edges towards more positive potential values. The degree of shift increased with surface charge density. In the dark, the flat band potential (measured by Mott–Schottky technique) and the onset potential were shifted by up to 300 mV depending on surface charge density. Relatively less of a shift was observed during illumination of the system. Other surface characteristics, such as conversion efficiency and photoluminescence intensity, have been enhanced. The basis for these shifts and their implications with respect to control of interfacial processes are discussed.  相似文献   
168.
Porous polymer composites have been synthesized by polymerizing the continuous phase of styrene/divinylbenzene high internal phase emulsions in the presence of organophilic montmorillonite clay having a novel oil‐based intercalant which is a reactive methacryl derivative of quaternized methyl oleate. The morphological features, thermal stability and mechanical properties, namely compression modulus and crush strength of the resulting composites have been investigated as a function of degree of nanoclay loading. All the composites reinforced with the clay were found to have improved thermal and mechanical properties as well as desired porous and interconnected structural morphology, as compared with the bare polyHIPE matrix. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41333.  相似文献   
169.
Open porous polyester composites were prepared by the crosslinking of unsaturated polyester resin and divinylbenzene in water‐in‐oil concentrated emulsion templates with the presence of a conventional surface modified montmorillonite nanoclay. Medium and high internal phase emulsions with either 55 or 80 wt% of internal phase were used as templates. The effect of monomer composition, emulsifier concentration, and internal phase amount on the emulsion stability and the morphology of the resulting porous composites were investigated. Moreover, the morphological properties of the resulting composites were determined depending on the amount of nanoclay loading. It was found that the morphological features, namely surface area and cell diameter, were altered dramatically with the amount of nanoclay loading. An important part of the research was focused on the variation of mechanical and thermal properties with the incorporation of nanoclay particles. The mechanical properties were improved both with the nanoclay incorporation and the use of medium internal phase emulsions. However, the used nanoclay did not have a significant effect on the thermal stability of the resulting composites. POLYM. COMPOS., 37:1531–1538, 2016. © 2014 Society of Plastics Engineers  相似文献   
170.
Previously, galectin-1 (GAL1) was found to be up-regulated in obesity-prone subjects, suggesting that use of a GAL1 inhibitor could be a novel therapeutic approach for treatment of obesity. We evaluated thiodigalactoside (TDG) as a potent inhibitor of GAL1 and identified target proteins of TDG by performing comparative proteome analysis of white adipose tissue (WAT) from control and TDG-treated rats fed a high fat diet (HFD) using two dimensional gel electrophoresis (2-DE) combined with MALDI-TOF-MS. Thirty-two spots from a total of 356 matched spots showed differential expression between control and TDG-treated rats, as identified by peptide mass fingerprinting. These proteins were categorized into groups such as carbohydrate metabolism, tricarboxylic acid (TCA) cycle, signal transduction, cytoskeletal, and mitochondrial proteins based on functional analysis using Protein Annotation Through Evolutionary Relationship (PANTHER) and Database for Annotation, Visualization, Integrated Discovery (DAVID) classification. One of the most striking findings of this study was significant changes in Carbonic anhydrase 3 (CA3), Voltage-dependent anion channel 1 (VDAC1), phosphatidylethanolamine-binding protein 1 (PEBP1), annexin A2 (ANXA2) and lactate dehydrogenase A chain (LDHA) protein levels between WAT from control and TDG-treated groups. In addition, we confirmed increased expression of thermogenic proteins as well as reduced expression of lipogenic proteins in response to TDG treatment. These results suggest that TDG may effectively prevent obesity, and TDG-responsive proteins can be used as novel target proteins for obesity treatment.  相似文献   
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