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1.
In checking harvesting discipline and quality control for oil palm fruits, color has presumably been an important guide to whether the oil content has reached a maximum where the fruit bunch is ready for cutting. However, establishing a single and harmonious standard base on color is a very contentious issue in the oil palm industry because of the subjective nature of the human vision of color. This was further complicated due to the lack of information on fruit color upon which to base a definite ripeness criterion. We demonstrated in this paper that this problem can be solved using machine vision technology. Methods used were to treat color in HSI (Hue, Saturation and Intensity) color space and applied multivariate discriminant analysis. These have proven to be highly effective for color evaluation and image processing. The vision system was trained to classify oil palms into four quality grades according to PORIM (Palm Oil Research Institute of Malaysia) inspection standards. These are the unripe, the underripe, the optimally ripe and the overripe classes. Depending upon the quality feature evaluated, misclassification by the vision system varied from 5 to 12% but averaged at about 8%. Machine vision disagreement ranged from 2 to 19%.  相似文献   
2.
In this study, an efficiently employed ionic liquid combined with commercially available silica gel (SG–ClPrNTf2) was developed for selective detection of gold(III) by use of inductively coupled plasma–optical emission spectrometry (ICP-OES). The selectivity of SG–ClPrNTf2 was evaluated towards seven metal ions, including Y(III), Mn(II), Zr(IV), Pb(II), Mg(II), Pd(II) and Au(III). Based on pH study and distribution coefficient values, the SG–ClPrNTf2 phase was found to be the most selective towards Au(III) at pH 2 as compared to other metal ions. The adsorption isotherm of Au(III) on the SG–ClPrNTf2 phase followed the Langmuir model with adsorption capacity of 59.48 mg g?1, which was highly in agreement with experimental data of adsorption isotherm study. The kinetics study indicated that Au(III) adsorption kinetics data were well fit with the pseudo-second-order kinetic model on the basis of correlation coefficient fitting (0.996) and adsorption capacity agreement (62.26 mg g?1). Furthermore, SG–ClPrNTf2 phase was effectively performed for the determination of Au(III) in real water samples with satisfactory results.  相似文献   
3.
Complex impedances of some magnesium-zinc ferrites, MgxZn1-xFe2O4 (x=0.4, 0.5, 0.6 and 0.7), in the frequency range of 1 mHz-10 MHz were measured at 300 K. The complex-plane impedance spectrum from each sample indicates that the capacitive and the resistive properties of the materials are mainly attributed to the processes that associated with the bulk (grain) and the grain boundary. A low-frequency dispersion (LFD) and a negative capacitance regions are also observed at low frequencies. A small series resistance of about the same value for all samples is also observed. The bulk and the grain boundary components are analysed by assuming a two-layer leaky capacitor. The simulated complex impedances using the Cole-Cole expression are in agreement with the measured values. The dielectric properties of the materials are attributed to the interfacial polarization and LFD at low frequencies and the orientational polarization at high frequencies. These properties result in the dielectric loss which composed of a Debye-like loss peak at high frequency end and a strong LFD below 1 Hz. Both regions exhibit universality with regard to the power-law relation between the dielectric loss (ε″r or χ″) and frequency as given by ε″r∝ωn-1, where n=0.14 and n=0.02, respectively. The exponent is marginally negative, n=−0.03, in the region of negative capacitance below 3–4 mHz. The variations of the above properties and the characteristic parameters for different compositions of the Mg-Zn ferrites are discussed. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
4.
Presently, the global search for alternative renewable energy sources is rising due to the depletion of fossil fuel and rising greenhouse gas (GHG) emissions. Among alternatives, hydrogen (H2) produced from biomass gasification is considered a green energy sector, due to its environmentally friendly, sustainable, and renewable characteristics. However, tar formation along with syngas is a severe impediment to biomass conversion efficiency, which results in process-related problems. Typically, tar consists of various hydrocarbons (HCs), which are also sources for syngas. Hence, catalytic steam reforming is an effective technique to address tar formation and improve H2 production from biomass gasification. Of the various classes in existence, supported metal catalysts are considered the most promising. This paper focuses on the current researching status, prospects, and challenges of steam reforming of gasified biomass tar. Besides, it includes recent developments in tar compositional analysis, supported metal catalysts, along with the reactions and process conditions for catalytic steam reforming. Moreover, it discusses alternatives such as dry and autothermal reforming of tar.  相似文献   
5.
In the present work, the proximate compositions, minerals and trace element contents of zander ( Sander lucioperca ) caught from two lakes (Beyşehir Lake and Seyhan Dam Lake) of Turkey were compared. There were significant differences between moisture and lipid contents, although there were no statistically significant differences between crude protein and ash contents. The mineral and trace elements determined were Na, K, Ca, P, Mg, Zn, Cu, Fe, Pb and Se. Although Na and Fe contents of zanders in two different lakes were different from each other ( P <  0.01), we found no statistically significant differences in terms of Mg, Ca, P, Cu, Pb, Se, Zn contents ( P >  0.01). Among the minerals analyzed, K was the highest followed by P, Ca, Na and Mg. The most abundant trace elements were Zn, Fe, Cu, Se followed by Pb, and these elements were below the limits proposed by Turkish Food Codes for human consumption in the meat of zander.

PRACTICAL APPLICATIONS


This present study includes information about the nutritional value of zander, which lives in the fresh water lakes of our country and of which people are fond and is being exported. The comparison of the proximate, mineral and trace element contents of the same species which are caught in two different lakes has been made. In the scope of human nutrition, in accordance with the minerals which have got much importance, it involves useful information about what the position of this fish is, and whether it contains any risk due to trace elements. Furthermore, concerning this subject, it will also light the way for studies to be made in the future.  相似文献   
6.
The residence time distribution (RTD) of food and inert particles flowing in a swept surface heat exchanger at room temperature was investigated. The effects of selected experimental conditions on RTD include particle shape (cube, cylinder, and sphere), particle concentration (10, 20, and 30% w/v), particle type (potato, carrot, turkey, green peas, and polystyrene), fluid viscosity (water, 0.5% CMC, and 1.0% CMC), bulk flow rate (5.8 × 10?4, 7.28 × 10?4, and 8.71 × 10?4 m3/s) and shaft rotational speed (30, 60, and 90 rpm). Although turkey cubes were denser than other food particles, they moved faster than potato and carrot particles. Mean particle normalized residence time (MNPRT) of food particles (green peas) were found to be significantly higher than that of simulated particles (polystyrene). Cylindrical particles stayed longer than cubic particles in water, but not significantly in CMC solution. MNPRT values were found to be dependent on viscosity. Increasing particle concentration (up to 30%) tended to decrease MNPRT. Both bulk flow rate and shaft rotational speed tend to decrease MNPRT, thus reducing the lethality achieved. The distribution of residence time curves were narrowed by decreasing particle concentration, bulk flow rate, and shaft rotational speed, and by using fluids with high viscosity. In general, particle velocity was found to be higher than the average bulk velocity. The fastest particle velocity was found to be 3.23 times the average bulk velocity while the ratio was 0.382 for the slowest.  相似文献   
7.
ABSTRACT

A fast and efficient Successive Linear Programming (SLP) based Optimal Power Flow (OPF) method for improving economy through cost minimization in AC-DC systems is presented. The method uses a decoupled approach and solves a sequence of alternate P- and Q- optimizations till convergence. The proposed method is applied to a sample 30-bus, 5-converter AC-DC system and the results are presented.

The paper also discusses corrective control algorithms for Improving system security in AC-DC systems. The benefits of the extra DC controls in improving economy and security are broughtout through studies on the same AC-DC system.  相似文献   
8.
Methylenetetrahydrofolate reductase (MTHFR) deficiency is the most common genetic cause of hyperhomocysteinemia, which has been implicated in the etiology of recurrent spontaneous abortion (RSA). This study was designed to investigate the association between two single nucleotide polymorphisms (SNP) (rs1801133 [C677T] and rs1801131 [A1298C]) in the MTHFR gene and RSA, in Saudis. These two SNPs were selected as these polymorphisms have a different effect on the activity and stability of the enzyme, and significantly diverse effects have been reported in relation to the association with RSA. Ethical approval was acquired from the IRB at King Saud University (KKUH), Saudi Arabia, and written informed consent was obtained from each participant. The study group comprised of 100 Saudi women with unexplained RSA and 100 age-matched controls, both attending KKUH for a routine checkup. Blood was drawn in EDTA tubes, and DNA was extracted. Genotyping was conducted using TaqMan SNP genotyping assay kits. The frequency of the T allele of C677T was 0.165 in patients and 0.17 in controls. Genotype frequencies for CC, CT and TT genotypes were 70%, 27% and 3%, respectively in RSA, and 71%, 24% and 5%, respectively, in the controls (p > 0.05). For the A1298C polymorphism, the C allele frequencies were 0.345 in patients and 0.28 in controls, while genotype frequencies for AA, AC and CC genotypes were 44%, 43%, and 13%, respectively, in patients, and 54%, 36%, and 10%, respectively, in controls (p > 0.05). The frequency of CC genotype and C allele of A1298C were higher in the patients with RSA, but not significantly, while C677T genotypes and allele frequencies did not differ between patients and controls. The results suggested that MTHFR gene polymorphisms are population-specific and may not associate with RSA in Saudi women.  相似文献   
9.
10.
万世轮回     
纪念碑是可以超越时间的纪念物. 我们从五行即金、木、水、火、土获得创作灵感,以演绎时间的轮回.五行平衡着阴阳两极,阳极代表生命的诞生,阴极代表生命的毁灭,天地万物在阴阳两极的统治下轮回.  相似文献   
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