全文获取类型
收费全文 | 2224篇 |
免费 | 97篇 |
国内免费 | 11篇 |
学科分类
工业技术 | 2332篇 |
出版年
2024年 | 11篇 |
2023年 | 64篇 |
2022年 | 78篇 |
2021年 | 137篇 |
2020年 | 87篇 |
2019年 | 107篇 |
2018年 | 125篇 |
2017年 | 85篇 |
2016年 | 94篇 |
2015年 | 53篇 |
2014年 | 77篇 |
2013年 | 155篇 |
2012年 | 87篇 |
2011年 | 114篇 |
2010年 | 84篇 |
2009年 | 85篇 |
2008年 | 74篇 |
2007年 | 74篇 |
2006年 | 57篇 |
2005年 | 40篇 |
2004年 | 42篇 |
2003年 | 28篇 |
2002年 | 25篇 |
2001年 | 21篇 |
2000年 | 25篇 |
1999年 | 20篇 |
1998年 | 64篇 |
1997年 | 45篇 |
1996年 | 39篇 |
1995年 | 27篇 |
1994年 | 30篇 |
1993年 | 22篇 |
1992年 | 14篇 |
1991年 | 27篇 |
1990年 | 25篇 |
1989年 | 25篇 |
1988年 | 18篇 |
1987年 | 14篇 |
1986年 | 10篇 |
1985年 | 12篇 |
1984年 | 13篇 |
1983年 | 13篇 |
1982年 | 12篇 |
1981年 | 9篇 |
1980年 | 4篇 |
1979年 | 10篇 |
1978年 | 11篇 |
1976年 | 6篇 |
1972年 | 6篇 |
1966年 | 4篇 |
排序方式: 共有2332条查询结果,搜索用时 31 毫秒
101.
Iftikhar Ahmad M. Mohib Ur Rehman Masroor Khan Ahmad Abbas Sarmad Ishfaq Sohail Malik 《国际能源研究杂志》2019,43(10):5384-5391
Battery is the sole power source for Internet of thing (IoT) sensors. Due to limited shelf life, the batteries are required to be replaced intermittently. This periodic replacement of batteries is inflated in terms of both logistics and time. This article illustrates conceptual design, development, and characterization of a flow‐based electromagnetic‐type energy harvester (F‐EH) using microplanar coil for IoT sensors application. The F‐EH converts hydro energy into useful electrical energy utilizing electromagnetic transduction mechanism. The microfabrication and macrofabrication techniques adopted to manufacture harvester's components are presented. The F‐EH has been successfully characterized by laboratory scale experimental flow test loop commissioned for this work. Experimentation with associated uncertainty analysis prevails that at a matching impedance, the F‐EH can generate a 686 μW of maximum power at an operating flow rate of 12 L/min with an uncertainty of 8.1%. 相似文献
102.
Khan Humaira Rashid Akram Bilal Aamir Muhammad Malik Muhammad Azad Tahir Asif Ali Choudhary Muhammad Aziz Akhtar Javeed 《Journal of Materials Science: Materials in Electronics》2021,32(16):20946-20954
Journal of Materials Science: Materials in Electronics - A photoelectrochemical (PEC) water splitting ability of pure ZnO and manganese-incorporated ZnO thin films fabricated via a simple... 相似文献
103.
Gupta Saurabh Tolani Varun Davidson James Levine Sergey Sukthankar Rahul Malik Jitendra 《International Journal of Computer Vision》2020,128(5):1311-1330
International Journal of Computer Vision - We introduce a neural architecture for navigation in novel environments. Our proposed architecture learns to map from first-person views and plans a... 相似文献
104.
Rajender Singh Malik Sandeep Nath Tripathi Deeksha Gupta Veena Choudhary 《International Journal of Hydrogen Energy》2014
Novel composite membranes were prepared using imidazolium type aprotic ionic liquids and sulfonated poly (ether ketone) (SPEK) as polymer matrix by solution casting process. All the prepared membranes were characterized for their thermal stability, mechanical properties, ion exchange capacity, proton conductivity and leaching out of ionic liquids in presence of water. Ionic liquid based membranes were more flexible than neat SPEK membrane due to the plasticization effect of ionic liquids. The interactions and compatibility occurring among components were investigated by vibration spectroscopy (FTIR ATR) and scanning electron microscopy respectively. The thermal stability of composite membranes was higher than unmodified membranes. The ion conductivity of composite membranes under anhydrous conditions was found to be dependent on temperature, type and concentration of ionic liquid in SPEK matrix. Ion conductivities of composite membranes under anhydrous condition were found to be up to two orders (∼100 times) higher than neat SPEK membrane and it was found to be ∼5 mS/cm at 140 °C for SPEK/OTf-70. These composite membranes can be successfully operated at temperatures ranging from 40 °C to 140 °C under anhydrous conditions. 相似文献
105.
Optimisation and comparative study on the addition of shrimp protein hydrolysate and shrimp powder on physicochemical properties of extruded snack 下载免费PDF全文
Annamalai Jeyakumari Mampuzha Sivadas Rahul Das Jaganath Bindu Chalil George Joshy Aliyamveetil Abubacker Zynudheen 《International Journal of Food Science & Technology》2016,51(7):1578-1585
The effect of an addition of shrimp protein hydrolysate and shrimp powder on the physicochemical properties of extruded snack was studied. Rice flour and cornflour were used as base materials, and extrusion was done using corotating twin‐screw extruder. A mixture response surface methodology was used to study the effect of ingredient mixture on the physical, functional and sensory properties of extrudates. Linear and quadratic mixture response regression model was fitted to the response variables, and it was evaluated using R2 values. Based on the desirability function score, the optimum combination of ingredient was 47.75% rice flour, 38.64% cornflour, 5.95% hydrolysate and 7.67% shrimp protein powder. It was observed that an addition of shrimp hydrolysate more than 5% (7.5%) improved the crispiness. Sensory evaluation revealed that shrimp hydrolysate and shrimp powder can be used at 5–7.5% level for developing protein‐rich extruded products without affecting sensory characteristics. 相似文献
106.
Rayees Ahmad Shiekh Ismail Ab RahmanSam’an Malik Masudi Norhayati Luddin 《Ceramics International》2014
A nanohydroxyapatite–silica powder was synthesized using an ethanol based sol–gel technique. The synthesized powder was incorporated into commercial glass ionomer powder (Fuji II GC) and characterized using FTIR, 29Si CP/MAS NMR, EDX and XRD spectroscopy. 29Si CP/MAS NMR results showed the presence of higher degree of cross-linking of silyl species between silica and GIC, which makes the Nano-HA–Silica–GIC composite much stronger. High-resolution transmission electron microscopy (TEM) and scanning electron microscopy (TEM) was employed to investigate the morphology of the synthesized powder. Results revealed that higher content of nanosilica produced a denser and stronger GIC. Thus, the application of nanohydroxyapatite–silica–GIC with improved properties are envisioned to be of great clinical importance, especially in stress bearing areas. 相似文献
107.
Jane H. Fujiyama-Novak Amrita Mukherjee Ganesh Rahul Bhimanapati Chethan Kumar Gaddam Randy L. Vander Wal Benjamin Ward 《Combustion and Flame》2012,159(3):1160-1164
In this study the main objective was to develop and demonstrate a glow discharge microplasma coupled to a miniature spectrometer for detection of fire signatures from pyrolyzing and burning spacecraft materials. Our experimental results demonstrate that combustion-produced carbonaceous aerosols can serve to identify the burning materials. Demonstrating versatility for chemistry analysis, the plasma detector could differentiate carbonaceous aerosols with different C/H ratios and distinguish inorganic samples such as salts and metal oxides from carbonaceous aerosols. In addition, in situ analysis of aerosol samples validated the microplasma’s analytical utility by linearity of its optical emission intensity with aerosol elemental composition. 相似文献
108.
Elsabé Jones Elizabeth Ojewole Rahul Kalhapure 《Drug development and industrial pharmacy》2014,40(5):669-679
Drug delivery via the buccal route has emerged as a promising alternative to oral drug delivery. Didanosine (DDI) undergoes rapid degradation in the gastrointestinal tract, has a short half-life and low oral bioavailability, making DDI a suitable candidate for buccal delivery. Recent developments in buccal drug delivery show an increased interest toward nano-enabled delivery systems. The advantages of buccal drug delivery can be combined with that of nanoparticulate delivery systems to provide a superior delivery system. The aim of this study was to design and evaluate the preparation of novel nano-enabled films for buccal delivery of DDI. Solid lipid nanoparticles (SLNs) were prepared via hot homogenization followed by ultrasonication and were characterized before being incorporated into nano-enabled monolayered multipolymeric films (MMFs). Glyceryl tripalmitate with Poloxamer 188 was identified as most suitable for the preparation of DDI-loaded SLNs. SLNs with desired particle size (PS) (201?nm), polydispersity index (PDI) (0.168) and zeta potential (?18.8?mV) were incorporated into MMFs and characterized. Conventional and nano-enabled MMFs were prepared via solvent casting/evaporation using Eudragit RS100 and hydroxypropyl methylcellulose. Drug release from the nano-enabled films was found to be faster (56% versus 20% in first hour). Conventional MMFs exhibited higher mucoadhesion and mechanical strength than nano-enabled MMFs. SLNs did not adversely affect the steady state flux (71.63?±?13.54?µg/cm2?h versus 74.39?±?15.95?µg/cm2?h) thereby confirming the potential transbuccal delivery of DDI using nano-enabled MMFs. Nano-enabled buccal films for delivery of DDI can be successfully prepared, and these physico-mechanical studies serve as a platform for future formulation optimization work in this emerging field. 相似文献
109.
Shaily M. Bhola Rahul Bhola Brajendra Mishra David L. Olson 《Journal of Materials Science》2010,45(22):6179-6186
Electrochemical impedance spectroscopic characterization of the low modulus Ti–35.5Nb–7.3Zr–5.7Ta alloy has been performed
in phosphate buffer saline solution at 37 °C. Measurements were performed at various immersion intervals up to 720 h at OCP
and also at various anodic potentials up to 2 V. The alloy exhibits a two time constant impedance response at the OCP and
a one-time constant response at anodic potentials in the passive region. The thickness of the oxide film formed has been evaluated
and the electrochemical interpretation of the results has been reported. Cyclic potentiodynamic profile of the alloy displays
valve metal characteristics and the presence of a wide passive region that extends up to the maximum potential value of 2 V
studied. 相似文献
110.
Hailey S. Reynolds Rahul Ram Fiona A. Charalambous Frank Antolasic James Tardio Suresh Bhargava 《Minerals Engineering》2010,23(9):739-745
Uranium bearing ores are often a complex mixture of minerals and compounds, a number of which are not of economic importance and are commonly referred to as gangue materials. In order to improve the efficiency of the dissolution stage of the overall uranium extraction process, a greater understanding of the minerals and compounds present in the ore is required. A greater knowledge of the gangue materials present is important as they can influence various aspects of the dissolution process such as providing potential adsorption sites for aqueous uranium species and through influencing the equilibrium of reactions involving aqueous uranium species. In this study the mineralogy of a uranium ore was investigated using a range of X-ray diffraction (XRD) based methods including in situ high temperature XRD and XRD using a synchrotron beam line. The results obtained from standard XRD (Cu Kα), high temperature XRD and synchrotron XRD (16.534 keV) were compared and a number of minerals were identified. The improved spatial resolution and intensity of the synchrotron data allowed for superior phase identification of a variety of minerals where standard X-ray techniques gave inconclusive results. 相似文献