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21.
The investigation was intended to examine the influence of selected moisture levels (4.26, 12.66, 25.31, 37.89, 50.21% wet basis) on engineering properties namely, dimensional, gravimetric, frictional, aerodynamic as well as mechanical properties of five selected varieties of sesame seed namely GT-3, GT-4, GJT-5, GT-6, and TKG 22. The investigation finds out that fluctuations in moisture level significantly (p ≤ 0.05) influenced the engineering properties assessed. Increase in moisture content influenced a rise in length, width, thickness, geometric mean diameter, arithmetic mean diameter, sphericity, volume, volumetric expansion coefficient, elongation ratio, flakiness ratio, surface area, projected area, thousand seeds weight, compressibility index, Hausner ratio, angle of repose, coefficient of friction, terminal velocity and Reynolds number of selected sesame verities. Whereas, a reverse trend was observed in aspect ratio, true density, bulk density, tapped densities, drag coefficient, and hardness with moisture content variation. The frictional characteristic of the seed showed improved stability with less flow ability at higher moisture levels. These outcomes disclosed that variation of seed moisture content is authoritative during designing and construction of machinery and process equipment related to sesame. It may be also beneficial in computation of design for hoppers, silos, conveyors, drying, and heat transfer equipment as well as other sesame seed-related process and handling equipment.  相似文献   
22.
In this work, the possibility of finding newly formed Maillard reaction products produced as a result of the subcritical water extraction (SWE) conditions is explored. Simplified powdered glycation model systems were prepared mixing amino acid (Lys, Arg or Ala) and glucose in a molar ratio 1:4. Samples constituted by glucose or amino acids alone were also prepared as controls. SWE was carried out at room temperature, 100 °C and 200 °C and 100 bar of pressure for 20 min. Different assays were performed in order to determine the extent of glycation by analyzing the decrease of free amino groups and/or the formation of Maillard reaction products (early, advanced and end products). Namely, formation of early colorless Maillard reaction products, Amadori compounds, was detected by ESI-MS; advanced glycation end products (AGEs) were detected by measuring the fluorescence intensity (λex = 360 nm, λem = 460 nm) while end brown products were detected by reading the absorbance at 360 and 420 nm. Besides, the antioxidant capacity of the aqueous extracts was determined by using ABTS and ORACFL assays. Results obtained indicated the occurrence of the Maillard reaction under our specific extraction conditions. Early, advanced and end products were detected in the samples. Caramelization of sugar also occurred. As expected, the extent of the non-enzymatic browning depended on the intensity of the thermal treatment. Additionally, data on antioxidant activity suggested the formation of neoantioxidants. These compounds were predominantly formed at 200 °C. In conclusion, this report demonstrates the formation of antioxidant compounds in simplified glycation model systems under SWE conditions.  相似文献   
23.
We present a methodology for the in‐process control of design inspection focusing on escaped defects. The methodology estimates the defect escape probability at each phase in the process using the information available at the beginning of a particular phase. The development of the models is illustrated by a case involving data collected from the design inspections of software components. The data include the size of the product component, as well as the time invested in preparing for the inspection and actually carrying it out. After smoothing the original data with a clustering algorithm, to compensate for its excessive variability, a series of regression models exhibiting increasingly better fits to the data as more information becomes available was obtained. We discuss how management can use such models to reduce escape risk as the inspection process evolves. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
24.
A dual‐mode circularly polarized compact antenna with integrated left‐hand and right‐hand circular polarization (LHCP and RHCP) is presented in this work. A multilayer arrangement of a square patch and square ring structure with an irregular transmission line is analyzed for dual‐band, dual‐CP operation. To realize dual mode propagation the proposed structure is excited using electromagnetic coupling technique. Succeeding proximity feeding with T‐stub match is analyzed, which conveys impedance bandwidth of 180 and 300 MHz within |S11| < ?10 dB at 3.5 and 5.5 GHz. The designed CP elements is suitably arranged with feed line for generating two orthogonal polarization of equal amplitude and a 90° phase difference at both the resonant modes (TM10 and TM01). Alterable LHCP and RHCP performance is realized by altering the compensated position and peculiar angle. Having both LHCP and RHCP polarization this design shows polarization insensitive characteristic. Each LHCP and RHCP antenna element accomplished a 3‐dB AR of 70 and 120 MHz with a gain up to 6 dBi. With a low profile of 0.27λ0 × 0.27λ0 × 0.04λ0, the CP antenna is fabricated, and the performance is validated through experimental analysis. With all the viable characteristics, the antenna is proposed for Wi‐MAX/WLAN communication.  相似文献   
25.
Applied 3 readability formulas differing in criterion for comprehension to the Personality Inventory for Children (PIC), PIC—Revised, and abbreviated forms of the PIC to investigate overall readability. Reading difficulty ranged from the 5th- to 6th-grade level for the least stringent formula to the mid-7th-grade level for the most stringent formula, and readability of abbreviated forms approximated readability of the entire PIC. It is recommended that mid-6th-grade reading skills be required of PIC respondents. (7 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
26.
Platinum nanoparticles were synthesized by mixing of two micro emulsions. Synthesized platinum nanoparticles were characterized by dynamic light scattering (DLS) and transmission electron microscope (TEM). Nanoparticles stability was analyzed using transmission and backscattering profiles of colloidal platinum solution. Catalytic activity of synthesized colloidal platinum nanoparticles was checked for the reduction of 4-nitrophenol and 4-nitrobenzo 15-crown compound and monitored by ultraviolet-visible absorption spectroscopy. Effects of amount of catalyst and amount of reducing agent were also studied. The reaction was found to follow pseudo-first-order kinetics with respect to nitro compound.  相似文献   
27.
28.
Atomic force microscopy studies of Bowen Basin coal macerals   总被引:1,自引:0,他引:1  
The porous structure of Bowen Basin coal macerals is very important in the storage and transport of coal seam gases. As part of a full characterization of this porosity, several coal macerals were examined by atomic force microscopy. Mesopores of ≥ 8 nm deriving from different types of porosity were imaged. The pores were either formed by contact points between spherical clusters of molecules or were defined channels that had been created by some physical process. The potential of this technique for characterizing the porous structure in greater depth was demonstrated.  相似文献   
29.
30.
Subcritical water extraction (SWE) is a very promising technique for obtaining bioactives (mainly antioxidants) from natural sources; even if sometimes the high operation temperatures have been suggested as responsible for thermal degradation of bioactives, the fact is that this type of extraction processes may generate new bioactive (antioxidant) compounds. The present study involved the analysis of antioxidants either naturally found in raw samples and/or those formed during extraction via Maillard reaction and other chemical events. Samples of different nature like microalgae (Chlorella vulgaris), algae (Sargassum vulgare, Porphyra spp., Cystoseira abies-marina, Sargassum muticum, Undaria pinnatifida, and Halopitys incurvus) and plants (rosemary, thyme and verbena) were studied. Amino acid availability, sugar content, fluorescence and absorbance at different wavelengths were determined to follow chemical changes due to reactions such as Maillard, caramelization and thermoxidation. Folin reaction also provided information related to total phenol content of the samples. ABTS+, peroxyl as well as superoxide radical scavenging assays were used to measure the antioxidant capacity of the extracts. Results obtained from this study suggest that neoformed compounds derived from Maillard, caramelization and thermoxidation reactions affect the overall antioxidant capacity of water subcritical extracts depending on the nature of the sample. The brown algae U. pinnatifida was the sample in which these chemical events contributed to a higher extent to improve the antioxidant capacity (from 0.047 to 1.512 mmol/g and from 45.356 to 1522.692 μmol/g for the TEAC and ORACFL methods, respectively) when the extraction temperature was raised from 100 to 200 °C. To the best of our knowledge, this is the first work supporting the formation of neoantioxidants in natural complex matrices during subcritical water extraction.  相似文献   
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