全文获取类型
收费全文 | 129篇 |
免费 | 6篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 1篇 |
综合类 | 1篇 |
化学工业 | 25篇 |
金属工艺 | 4篇 |
机械仪表 | 5篇 |
建筑科学 | 2篇 |
矿业工程 | 1篇 |
能源动力 | 11篇 |
轻工业 | 10篇 |
水利工程 | 4篇 |
无线电 | 16篇 |
一般工业技术 | 26篇 |
冶金工业 | 10篇 |
自动化技术 | 20篇 |
出版年
2023年 | 2篇 |
2022年 | 5篇 |
2021年 | 6篇 |
2020年 | 4篇 |
2019年 | 5篇 |
2018年 | 11篇 |
2017年 | 11篇 |
2016年 | 11篇 |
2014年 | 11篇 |
2013年 | 10篇 |
2012年 | 12篇 |
2011年 | 15篇 |
2010年 | 5篇 |
2009年 | 6篇 |
2008年 | 3篇 |
2007年 | 3篇 |
2006年 | 4篇 |
2005年 | 2篇 |
2004年 | 2篇 |
2003年 | 3篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1994年 | 1篇 |
1993年 | 1篇 |
排序方式: 共有136条查询结果,搜索用时 15 毫秒
1.
In this report the important factors affecting the levitation melting of nickel are discussed. The relationship between the
temperature of a levitated sample to factors such as coil design, gas flow rate, power input, and sample weight are studied.
Different coil designs were investigated and compared. It was found that for satisfactory sustained levitation melting, the
sample weight, depending on the material, must be within a particular range. Furthermore, increasing the power input would
result in a decrease in the droplet temperature; and increasing the weight of the sample results in an increase in the temperature.
The flow rate of a cooling gas has a reverse relationship to the temperature. A mathematical model for the calculation of
levitation force and temperature for different coils and samples was developed. The experimental values are in good agreement
with calculations of the model. 相似文献
2.
Hassan Mahmoodi Esfanddarani Abolghasem Abbasi Kajani AbdolKhalegh Bordbar 《IET nanobiotechnology / IET》2018,12(4):412
High‐quality colloidal silver nanoparticles (AgNP) were synthesised via a green approach by using hydroalcoholic extracts of Malva sylvestris. Silver nitrate was used as a substrate ion while the plant extract successfully played the role of reducing and stabilising agents. The synthesised nanoparticles were carefully characterised by using transmission electron microscopy, atomic‐force microscopy, energy dispersive X‐ray spectroscopy, Fourier transform infrared spectroscopy and UV–vis spectroscopy. The maximum absorption wavelengths of the colloidal solutions synthesised using 70 and 96% ethanol and 100% methanol, as extraction solvents, were 430, 485 and 504 nm, respectively. Interestingly, the size distribution of nanoparticles depended on the used solvent. The best particle size distribution belonged to the nanoparticles synthesised by 70% ethanol extract, which was 20–40 nm. The antibacterial activity of the synthesised nanoparticles was studied on Escherichia coli, Staphylococcus aureus and Streptococcus pyogenes using disk diffusion, minimum inhibitory concentrations and minimum bactericidal concentrations assays. The best antibacterial activity obtained for the AgNPs produced by using 96% ethanolic extract.Inspec keywords: silver, nanoparticles, nanofabrication, antibacterial activity, colloids, particle size, transmission electron microscopy, atomic force microscopy, X‐ray chemical analysis, Fourier transform spectra, infrared spectra, ultraviolet spectra, visible spectra, microorganisms, nanomedicine, biomedical materialsOther keywords: Green synthesis, flower extract, Malva sylvestris, antibacterial activity, high‐quality colloidal silver nanoparticles, hydroalcoholic extracts, plant extract, reducing agents, stabilising agents, transmission electron microscopy, atomic‐force microscopy, energy dispersive X‐ray spectroscopy, Fourier transform infrared spectroscopy, UV– vis spectroscopy, colloidal solutions, particle size distribution, Escherichia coli, Staphylococcus aureus, Streptococcus pyogenes, disk diffusion, minimum inhibitory concentrations, minimum bactericidal concentrations assays, ethanolic extract, size 430 nm, size 485 nm, size 504 nm, size 20 nm to 40 nm, Ag 相似文献
3.
Abolghasem Sadeghi-Niaraki Masood Varshosaz Kyehyun Kim Jason J. Jung 《Expert systems with applications》2011,38(10):11999-12008
This paper addresses a methodology to properly represent a road network in the geographic information system (GIS) for network analysis. Over the years, the real world has become too complex to model properly within a given information system, such as GIS. Ideally, when the real world is represented as accurately as possible, a GIS can answer a question in its virtual world that coincides with the exact answer in the real world. However, existing methods related to impedance modeling for each segment of a road network in a route planning analysis that includes only a distance or time variable do not give proper results. Hence, this study investigates how a road network can represent the real world in a GIS and offer route planning tools. To address this, first, additional realistic variables are taken into account. These include weather, sight-seeing information, road type, and so on. Second, to combine these variables, an impedance model (IM) using the analytical hierarchical process (AHP) method is proposed. Finally, all of the models are implemented and verified with a sensitivity analysis. The models were successfully implemented in this work. All of the paths of the route planning analysis were successfully matched with the drivers’ paths that would normally be chosen in reality. It is anticipated that the use of other techniques such as analytical network process (ANP) in addition to AHP would be useful to overcome the aforementioned problem. 相似文献
4.
M. Jalaal M.G. Nejad P. Jalili M. Esmaeilpour H. Bararnia E. Ghasemi Soheil Soleimani D.D. Ganji S.M. Moghimi 《Computers & Mathematics with Applications》2011,61(8):2267-2270
He’s homotopy perturbation method is applied to obtain exact analytical solutions for the motion of a spherical particle in a plane couette flow. It is demonstrated that the applied analytical method is very straightforward in comparison with existing techniques. Furthermore, it is decidedly effectual in terms of accuracy and rapid convergence. The formulation of the problem is presented in the text as well as the analytical and numerical procedures. The current results can be used in different areas of particulate flows. 相似文献
5.
Abolghasem Sayadian Fatemeh Mozaffari 《International Journal of Speech Technology》2017,20(3):587-592
This article puts forward a new algorithm for voice conversion which not only removes the necessity of parallel corpus in the training phase but also resolves the issue of insufficiency of the target speaker’s corpus. The proposed approach is based on one of the new voice conversion models utilizing classical LPC analysis-synthesis model combined with GMM. Through this algorithm, the conversion functions among vowels and demi-syllables are derived. We assumed that these functions are rather the same for different speakers if their genders, accents, and languages are alike. Therefore, we will be able to produce the demi-syllables with just having access to few sentences from the target speaker and forming the GMM for one of his/her vowels. The results from the appraisal of the proposed method for voice conversion clarifies that this method has the ability to efficiently realize the speech features of the target speaker. It can also provide results comparable to the ones obtained through the parallel-corpus-based approaches. 相似文献
6.
Mohammad Reza Ganjali Maryam Ghorbani Parviz Norouzi Azadeh Daftari Magid Faal-Rastegar Abolghasem Moghimi 《Sensors and actuators. B, Chemical》2004,100(3):315-319
A novel poly(vinyl chloride)-based 2,3,5,6,8,9-hexahydro-1,4,7,10-benzotetra oxacyclododecine-12-carbaldehyde-12-(2,4-dinitrophenyl)hy (PBC) with sodium tetraphenyl borate (NaTPB) as an anion excluder, benzyl acetate (BA), acetophenon (AP) and o-nitrophenyloctyl ether (NPOE) as plasticizing solvent mediators was prepared and investigated as a beryllium selective sensor. The best performance was observed with the membrane having the PVC–NaTPB–NPOE–PBC composition 30%:3%:62%:5%, which worked well over a very wide concentration range (1.0×10−7 M to 1.0×10−1 M). The sensor exhibits a Nernstian slope of 29.9 mV per decade of Be2+ activity. The detection limit of the sensor is 7.0×10−8 M (630 ppt). The proposed electrode shows excellent discriminating ability toward Be2+ ion with regard to alkali, alkaline earth, transition and heavy metal ions. It was successfully applied to the determination of beryllium in a mineral sample. 相似文献
7.
Hadi Kalani Alireza Akbarzadeh S. Nader Nabavi Sahar Moghimi 《Intelligent Service Robotics》2018,11(2):187-205
Human mastication is a complex and rhythmic biomechanical process which is regulated by a brain stem central pattern generator (CPG). Masticatory patterns, frequency and amplitude of mastication are different from person to person and significantly depend on food properties. The central nervous system controls the activity of muscles to produce smooth transitions between different movements. Therefore, to rehab human mandibular system, there is a real need to use the concept of CPG for development of a new methodology in jaw exercises and to help jaw movements recovery. This paper proposes a novel method for real-time trajectory generation of a mastication rehab robot. The proposed method combines several methods and concepts including kinematics, dynamics, trajectory generation and CPG. The purpose of this article is to provide a methodology to enable physiotherapists to perform the human jaw rehabilitation. In this paper, the robotic setup includes two Gough–Stewart platforms. The first platform is used as the rehab robot, while the second one is used to model the human jaw system. Once the modeling is completed, the second robot will be replaced by an actual patient for the selected physiotherapy. Gibbs–Appell’s formulation is used to obtain the dynamics equations of the rehab robot. Then, a method based on the Fourier series is employed to tune parameters of the CPG. It is shown that changes in leg lengths, due to the online changes of the mastication parameters, occur in a smooth and continuous manner. The key feature of the proposed method, when applied to human mastication, is its ability to adapt to the environment and change the chewing pattern in real-time parameters, such as amplitudes as well as jaw movements velocity during mastication. 相似文献
8.
Zoya Sadighi Abolghasem Ataie Mohammad Reza Barati 《Metals and Materials International》2014,20(1):77-81
In this study, barium-doped lanthanum manganite, La0.8Ba0.2MnO3, was synthesized via a mechano-thermal route employing high energy ball milling and subsequent heat treatment. The structural evolution, morphology and thermal behaviour of the powders were evaluated using XRD, FESEM, and DTA/TGA, respectively. DTA/TGA results showed that the calcination temperature of the carbonates significantly decreased by increasing the milling time. The results revealed that single phase perovskite was formed at 900 °C in a milled sample for 2 h and this temperature decreased to 600 °C by increasing the milling time to 30 h. The mean crystallite size also decreased from 32 to 20 nm by increasing the milling time from 2 to 30 h. The reaction sequence of La0.8Ba0.2MnO3 formation via the mechano-thermal route is proposed using XRD and DTA/TGA results. FESEM micrographs showed that the mean particle size of the perovskite phase is increased slightly from 30 to 40 nm by increasing the heat treatment temperature from 600 to 900 °C. 相似文献
9.
One of the main applications of time alignment is parallel corpus based voice conversion. In the literature, various methods such as dynamic time warping (DTW) and hidden Markov model have been suggested for time alignment of two speech signals. In this paper, we introduce some modifications to DTW in order to decrease the time alignment error. These modifications are refinement, which is done by exerting a threshold, normalization, and comparisons between the preceding and the following frames to make sound correspondence between two different parallel corpus-based speakers’ speeches. Evaluation of this approach which has been done on some corpus sentences indicates a significant improvement of time alignment. At least about 4% and in some cases 15% decrease of error in comparison with DTW has been achieved. 相似文献
10.
Improved physical stability of docosahexaenoic acid and eicosapentaenoic acid encapsulated using nanoliposome containing α‐tocopherol
下载免费PDF全文
![点击此处可从《International Journal of Food Science & Technology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Mohammad Ali Sahari Hamid Reza Moghimi Zahra Hadian Mohsen Barzegar Abdoreza Mohammadi 《International Journal of Food Science & Technology》2016,51(5):1075-1086
This study aimed to develop a nanoliposomal formulation containing α‐tocopherol loaded with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and to characterise the formulation by its physical stability. For this purpose, different nanoliposomal formulations with dipalmitoyl phosphocholine were prepared using a modified thin‐film hydration method and evaluated by particle size, polydispersity index (PDI), transmission electron microscopy, differential scanning calorimetry and determining the encapsulation efficiencies of DHA and EPA. A physical stability study was conducted by investigating the change in the vesicle encapsulation efficiency, particle size, PDI and shape when stored at 4, 30 and 40 °C for 3 months. High encapsulation efficiency of DHA and EPA (89.1% ± 0.6% and 81.9% ± 1.4%) and appropriate particle size (82 ± 0.8 nm) were obtained for liposomes composed of α‐tocopherol. The optimum formulation was stable for 90 days when kept at 4 °C. This study demonstrated that α‐tocopherol had a protective effect on the physical stability of the nanoliposomes containing DHA and EPA. 相似文献