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101.
The effects of pH, storage period, temperature, light and dark conditions on the stability of anthocyanins extracted from Tibouchina semidecandra flowers of different developmental stages was evaluated. Fully formed but unopened flower bud had the highest amount of total anthocyanin extracted from fresh petals. The anthocyanin contents for all flower developmental stages were stable at pH 0.5–3.0 but the colour of the extracts faded at higher pH values. Degradation percentages of total anthocyanins in the extracts kept at 25 °C were 7–20% lower than that maintained at 31 °C. Extracts stored in darkness at 25 °C maintained their purple colour for 26 days while light exposure reduced it to an average of 10 days. The study shows that suitable storage condition for coloured anthocyanin pigments in extracted form is in acidic conditions in the dark. This implies the potential usage of coloured anthocyanins as natural food colourants and shelf life indicator for acidic foods. 相似文献
102.
Atif Kamil Mubarak Ali Khan Muhammad AAsim Nadir Zaman Khan Raham Sher Khan Muhsin Jamal Waqar Ahmad Mir Azam Khan Fazal Jalil 《Biocell》2019,43(3):167-174
Several toxic compounds are known to induce apoptosis in mammalian cell lines. The human neuroblastoma
cells (SH-SY5Y) were exposed to the phosphatase inhibiting toxin okadaic acid (OA) or hydrogen peroxide (H2O2)
to induce apoptosis as well as generate reactive oxygen species (ROS). Mitoxantrone (MXT) was used as a positive
control for apoptosis. The SH-SY5Y cells were transfected with eukaryotic expression plasmid pHyPer-dMito encoding
mitochondrial-targeted fluorescent or pHyPer-dCito encoding cytoplasmic-targeted fluorescent sensor for hydrogen
peroxide (HyPer). The ERp57, also called GRP58 (Glucose-regulated protein 58), is a stress protein induced in
conditions like glucose starvation and viral infection. Recently ERp57 was shown to translocate from the endoplasmatic
reticulum to the cell surface in anthracycline-induced apoptotic cells. ERp57 co-translocation together with calreticulin
has been suggested to be crucial for recognizing tumor cells to induce immunogenic cell death. ERp57 translocation
after exposure to okadaic acid was studied using immunofluorescence and confocal microscopy. These studies indicated
that okadaic acid has induced the translocation of ERp57 to the cellular membrane. 相似文献
103.
Babar Zaman Muhammad Hisyam Lee Muhammad Riaz Mu'azu Ramat Abujiya 《Quality and Reliability Engineering International》2019,35(6):1542-1581
Random causes are vital part of every process in manufacturing and nonmanufacturing environments, and these do not affect the product features. Special causes, on the other hand, come because of some burden(s) in a process and requires special attention; otherwise, it ruins the products excellence. Special causes are categorized into small, moderate, and large shifts and are handled by statistical quality control charts. The Shewhart control chart is well known for large shifts, while the cumulative sum and exponentially weighted moving average are more effective in detecting small to moderate shifts. However, in practice, many processes require the simultaneous monitoring of both the small to the large shifts. In this study, we have designed an adaptive EWMA for dispersion parameter in connection with Huber and Tukey's bisquare functions. The performance measures used in this study include average run length, extra quadratic loss, relative average run length, and performance‐comparison index. We have observed that the study proposals are good competitors to the other counter parts for an efficient monitoring of shifts of varying amounts. An illustrative example using real data is given to demonstrate the implementation of the study proposal. 相似文献
104.
Javed Ali S. Islam Sirajul Islam Gul Zaman 《Computers & Mathematics with Applications》2010,59(6):2000-2006
In this work, we solve multipoint boundary value problems using the Optimal Homotopy Asymptotic Method (OHAM).The proposed method is tested upon several problems from the literature and the results are compared with the available exact solution. This method provides easy tools to control the convergence region of approximating solution series where ever necessary. 相似文献
105.
106.
Khairul Anuar Mohamad ;Afishah Alias ;Ismail Saad ;Bablu Kumar Gosh ;Katsuhiro Uesugi ;Hisashi Fukuda 《化学与化工:英文版》2014,(5):476-481
The mixed P3HT (poly(3-hexylthiophene)) and [6,6]-PCBM (phenyl C61-butyric acid methyl ester) organic thin films were investigated for electronic structure using UV-Vis spectrophotometer and PESA (photo-electron spectroscopy in air). Furthermore, ESR (electron spin resonance) and AFM (atomic force microscopy) were used to investigate the surface morphology and molecular orientation, respectively. ESR analysis indicated the molecular orientation of the P3HT crystalline in the blend thin films, which the crystalline oriented normal to the substrate with distribution of 35°. AFM images indicated that the surface morphology of P3HT film was affected by the presence of PCBM nanoparticles. Solution-processed OTFTs (organic thin-film transistors) based on P3HT/PCBM blend thin film in a top source-drain contact structure was fabricated, and the electrical characteristics of the devices were also investigated. A unipolar property with p-channel characteristics were obtained in glove box measurement. 相似文献
107.
Temperature‐Insensitive High Strain in Lead‐Free Bi0.5(Na0.84K0.16)0.5TiO3–0.04SrTiO3 Ceramics for Actuator Applications 下载免费PDF全文
Rizwan Ahmed Malik Ali Hussain Adnan Maqbool Arif Zaman Chang‐Won Ahn Jamil Ur Rahman Tae‐Kwon Song Won‐Jeong Kim Myong‐Ho Kim 《Journal of the American Ceramic Society》2015,98(12):3842-3848
Lead‐free piezoelectric ceramics, 0.96[{Bi0.5 (Na0.84K0.16)0.5}1?xLix(Ti1?yNby)O3]–0.04SrTiO3 (BNKLiTN–ST) with x, y = 0–0.030, were synthesized by solid‐state reaction method. X‐ray diffraction patterns indicated that Li and Nb successfully diffused into the BNKT–ST lattice and formed a pure perovskite structure with x, y ≤ 0.025. Increasing the Li and Nb contents (x, y = 0.020) induced a phase transformation from the coexistent rhombohedral–tetragonal phases for pure BNKT–ST ceramics to a pseudocubic phase, resulting in degradation of the remnant polarization and coercive field. However, the field‐induced strain was markedly enhanced at x, y = 0.020, giving rise to a giant dynamic piezoelectric constant (d33* = Smax/Emax = 800 pm/V). Furthermore, the temperature dependence of the field‐induced strain response showed temperature‐insensitivity up to 120°C. To explore its potential for device applications, a 10‐layered stack‐type multilayer actuator was fabricated from the optimal composition (x, y = 0.020). This actuator showed a large Smax/Emax of 600 pm/V at a relatively low driving field of 4.5 kV/mm suggesting highly promising results in lead‐free BNT‐based ceramics. 相似文献
108.
Carbon nanotubes (CNTs) and the ones grown on MgO and alumina are used as supports for cobalt catalyst in Fischer–Tropsch (FT) synthesis. Carbon nanotubes were synthesized by chemical vapor deposition of methane on 5.0 wt.% iron on MgO or alumina at 950 °C. The carbon nanotubes were characterized by SEM and TEM microscopy and Raman spectroscopy. Cobalt nitrate was impregnated onto the supports by impregnation, and the samples were dried and reduced in-situ at 400 °C for 12 h, and then FT synthesis was carried out in a fixed-bed reactor. The catalysts were characterized by BET surface area measurement, TPR and TPD. The effect of carbon nanotubes as cobalt support on CO conversion, product selectivity, and olefin to paraffin ratio of FT synthesis was investigated and compared with activated carbon as well as Al2O3, as a traditional support. The results revealed that the activity of the Co/CNT catalyst was improved by 22%, compared to the conventional Co/alumina catalysts. Also the cobalt supported on CNTs grown on MgO (Co/CNT–MgO) shows the highest selectivity to C5+ as the most desired FTS products. The C5+ selectivity enhancement was about 37, 34, 17, and 77% as compared to the Co/CNT, Co/alumina, Co/CNTs-alumina, and Co/activated carbon, respectively. Also the olefin/paraffin ratio on the Co/CNTs-MgO catalyst is about 7.7 times higher than the conventional cobalt catalysts. It seems that the degree of reduction of cobalt is higher when supported on CNTs than on alumina. This leads to higher FTS activity. Also, the particle size distribution of the cobalt is affected by the CNT–MgO support leading to higher C5+ selectivity. 相似文献
109.
Ahmad Rafi Khairul Anuar Abdul Samad Maizatul Hayati Mazlan Mahadzir 《Automation in Construction》2005,14(6):707-715
Spatial ability is one of the cognitive means used in problem solving activities particularly when manipulating and processing visuo-spatial information. With the increasing use of network communication, conventional teaching and learning has shifted towards the development of network environments, online learning, real-time interaction and high quality multi-user collaboration. This paper presents our experiment using a Web-based Virtual Environment (WbVE) that has improved a group of pre-service teachers' spatial ability understanding for teaching Engineering Drawing for secondary school subjects. The experiment is carried out in Universiti Pendidikan Sultan Idris (UPSI) comprising of 98 pre-service teachers taking the Computer Aided-Design (CAD) course. Selected subjects were pre-tested at the beginning of the semester with spatial tests focusing on mental rotation and spatial visualization to provide the baseline measurement. A desktop WbVE, which was employed and tested in the CAD laboratories to improve their spatial ability for five weeks of instructional treatment, will be demonstrated. Post-testing of spatial tests revealed significantly the overall spatial ability improvements as measured by the test scores. This paper concludes with a discussion on the impact of WbVE spatial learning that will be used as a precedent in the development of the VE teaching and learning prototypes for secondary school in Malaysia. 相似文献
110.
A stand-alone digital relay has been designed and implemented. The relay can be modified easily to accommodate the protection of different types of transformers by changing the software only. Presented in this paper are the real-time experimental results of five selected algorithms implemented using this digital relay. These algorithms are: discrete Fourier transform, Walsh function, rectangular transform, finite impulse response and least-square. Based on the experimental results, the discrete Fourier transform (DFT) algorithm is found to be the best algorithm in terms of accuracy and speed for digital implementation of the differential relay for power transformers 相似文献