全文获取类型
收费全文 | 43篇 |
免费 | 4篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 12篇 |
机械仪表 | 1篇 |
建筑科学 | 1篇 |
能源动力 | 8篇 |
轻工业 | 11篇 |
无线电 | 2篇 |
一般工业技术 | 6篇 |
冶金工业 | 3篇 |
自动化技术 | 2篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 2篇 |
2020年 | 2篇 |
2019年 | 3篇 |
2018年 | 2篇 |
2017年 | 2篇 |
2016年 | 2篇 |
2014年 | 2篇 |
2013年 | 3篇 |
2012年 | 6篇 |
2011年 | 1篇 |
2008年 | 3篇 |
2007年 | 2篇 |
2006年 | 2篇 |
2005年 | 1篇 |
2004年 | 1篇 |
2002年 | 1篇 |
2001年 | 1篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1988年 | 1篇 |
1987年 | 3篇 |
1983年 | 1篇 |
排序方式: 共有47条查询结果,搜索用时 15 毫秒
1.
Sonication is a well‐known sludge pretreatment technique with the advantages of simple operation and high efficiency. However, it is an energy‐intensive process. Hence, it is very important to predetermine its sludge disintegration efficiency at varying pretreatment conditions in order to minimize the ultrasonic energy consumption. In this study, it was found that the ultrasonic sludge disintegration occurred in two stages: rapid and subsequent slow disintegration stages. For this reason, it was aimed to develop a simple and accurate mathematical model to describe the two‐stage sludge disintegration as a function of pretreatment conditions. Sludge concentration and ultrasonic density along with sonication period were involved in this model as independent variables. It was determined that the mathematical model can predict accurately the degree of sludge disintegration. Thus, the proposed model was seen to be very useful for evaluating the disintegration efficiency and/or for process design using the operating parameters under different conditions. 相似文献
2.
M. Mohammadizadeh I. Fidan M. Allen A. Imeri 《The International Journal of Advanced Manufacturing Technology》2018,99(5-8):1225-1234
This research study reports the creep behavior analysis of the new composite materials manufactured by 3D printing technology. Nylon was used as a polymer matrix, and carbon fiber, Kevlar, and fiberglass were used as reinforcing agents. Since the properties of 3D-printed components are usually insufficient for robust engineering applications, adding reinforcing fibers improves the performance of these components for several engineering applications. Fiber-reinforced additive manufacturing (FRAM) is an almost 4-year-old technology. Additionally, there is not sufficient research on the behavior of FRAM components specifically at high temperatures. Therefore, the investigation of the high-temperature behavioral analysis of FRAM components was focused on in this study. Creep properties of the composite specimens reinforced by different fibers were measured by the dynamic mechanical thermal analysis system. The statistical analyses were conducted to analyze the experimental data using mathematical models. The microstructural analysis was performed to further investigate parts’ morphology, 3D printing quality, and fracture mechanisms. The results indicated that the creep compliance of reinforced composite specimens was significantly improved in comparison with pure nylon. Overall, this paper presents quantitative creep analysis results demonstrating the capabilities of FRAM components to be used for several engineering applications. 相似文献
3.
4.
Allakhverdiev K Ismailov N Salaeva Z Mikailov F Gulubayov A Mamedov T Babaev S 《Applied optics》2002,41(1):148-153
We report the results of investigating a low-voltage, polarization-insensitive, reflective-type modulator based on an epsilon-GaSe crystal and operated at the 1.960-eV line of a He-Ne laser. We demonstrate that the modulation in an Al-epsilon-GaSe-Cu device results mainly from the Franz-Keldysh effect. Relatively high speed and low operating voltage could make these modulators with Schottky-barrier contacts attractive devices in the red range of the spectrum. 相似文献
5.
6.
The paper describes a method for predicting the load (compounding or excitation and external) characteristics of saturated cylindrical-rotor synchronous machines. The method is based upon the phasor diagram representation of a synchronous machine and utilizes a simple formula for approximating the magnetisation curve. This yields a closed form of expression for the excitation characteristics, while solution of the equations of the external load characteristics is carried out, easily, by using a simple iteration process. The validity of the approach is verified by tests. 相似文献
7.
A Imeri J M González R Flores L G Elías R Bressani 《Archivos latinoamericanos de nutrición》1987,37(1):132-146
The purpose of the present research was to establish the variability in agronomic, chemical and nutritional characteristics among 25 amaranth (A. caudatus) cultivars. A large variability was found among cultivars in all the parameters evaluated. Average seed weight was 0.75 mg, and had an average size of 1.23 x 1.14 mm. The average moisture, protein and fat content was 11.81, 12.66 and 8.44%, respectively. The average values for methionine, threonine, cystine, leucine and lysine were: 168, 276, 74, 381 and 370 mg/g N, in the same order as presented. It was possible to establish significant, positive correlations between yield-protein, methionine-cystine, methionine-lysine, and threonine-leucine, as well as significant negative correlations between protein-cystine, fat-methionine and cystine- leucine. Furthermore, it is not possible to select cultivars of higher yield on the basis of seed weight, since these two variables were negatively correlated, although not statistically significant. Among all 25 cultivars studied, some were deficient in sulfur-containing amino acids, while based on the FAO/WHO essential amino acid pattern, all of them were deficient in leucine. The average protein quality value expressed as NPR was 3.54 in thermally-processed samples, with no differences between cultivars. Nevertheless, protein digestibility values probably classified the samples in two groups with average values of 79 and 81%, respectively. The variability found can thus be used to select cultivars with higher yields and higher nutritional characteristics. 相似文献
8.
Oktar FN Agathopoulos S Ozyegin LS Gunduz O Demirkol N Bozkurt Y Salman S 《Journal of materials science. Materials in medicine》2007,18(11):2137-2143
Biologically derived hydroxyapatite from calcinated (at 850 °C) bovine bones (BHA) was doped with 5 wt% and 10 wt% of SiO2, MgO, Al2O3 and ZrO2 (stabilized with 8% Y2O3). The aim was to improve the sintering ability and the mechanical properties (compression strength and hardness) of the resultant
BHA-composites. Cylindrical samples were sintered at several temperatures between 1,000 and 1,300 °C for 4 h in air. The experimental
results showed that sintering generally occurs at 1,200 °C. The BHA–MgO composites showed the best sintering performance.
In the BHA–SiO2 composites, extended formation of glassy phase occurred at 1,300 °C, resulting in structural degradation of the resultant
samples. No sound reinforcement was achieved in the case of doping with Al2O3 and zirconia probably due to the big gap between the optimum sintering temperatures of BHA and these two oxides. 相似文献
9.
10.
Serkan Şahinkaya Mehmet Faik Sevimli 《Journal of Industrial and Engineering Chemistry》2013,19(1):197-206
The individual and combined effects of alkaline and ultrasonic pretreatment on both physical and chemical properties and anaerobic biodegradability of waste activated sludge (WAS) were investigated comprehensively in this study. The experimental results showed that both disintegration and anaerobic biodegradability of WAS were significantly improved by the combination of alkaline and ultrasonic (sono-alkaline) pretreatment. Besides, it was determined that the hydraulic retention time in anaerobic digester can be shortened by half using this combined pretreatment. However, it was also determined that sono-alkaline pretreatment was not feasible economically due to its high energy requirement. 相似文献