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21.
J. Dasgupta S. Adhikari M. M. Chakrabarty D. Bhattacharyya 《European Journal of Lipid Science and Technology》1982,84(3):111-114
The positional distribution of acyl groups in interesterified fats obtained from a number of vegetable oil-mixtures was studied by the selective deacylation reaction of Pancreatic Lipase. In the case of randomised fats, there was almost equal distribution of fatty acids in the three positions, which indicated completeness of randomisation and destruction of the selective orientation of acyl groups present in natural fats. On the other hand, there was little or no change in positional distribution during directed interesterification. It was found that for natural and randomised fats, the glyceride compositions calculated from the Lipase hydrolysis data agreed quite well with those obtained by argentation thin-layer chromatography (TLC) followed by gas-liquid chromatography (GLC) with an internal standard. The glyceride compositions of directed interesterified fats, found by argentation TLC followed by GLC, indicated that the proportions of GS3 and GU3 increase to a considerable extent with simultaneous decrease in GSU2, while that of GS2U increases to a comparatively small extent, or remains unchanged. 相似文献
22.
M. M. Chakrabarty D. Bhattacharyya A. K. Basu 《Journal of the American Oil Chemists' Society》1972,49(9):510-514
Conjugated hydrogenation of tung oil (fatty acid composition: elaeostearic 57.0%, linoleic 25.8%, oleic 11.2% and saturated
6.0%) has been investigated to ascertain the influence of hydrogen donors, namely primary and secondary alcohols, on rate
and selectivity under different operating conditions. 2-Propanol, in general, reflects faster rate and greater degree of reduction
but less selectivity towards the reduction of unsaturated acids than ethanol, when tung oil is treated at 200 C, 225 C and
250 C with 2% Ni (optimum catalyst level) and theoretical as well as 100% excess of theoretical amount of the two hydrogen
donors to ensure complete hydrogenation of the oil. The rate and degree of reduction with ethanol are less influenced by its
amount and amount of catalyst, but with 2-propanol these depend considerably on both the amount of hydrogen donor and amount
of catalyst. During conjugated hydrogenation of tung oil, deposition of gel-like mass in minor amount occurs only at the wall
of the reaction vessel. This is evidently due to polymerization of the conjugated trienoic acid.
Presented at the IXth ISF Congress, Rotterdam, September 1968. 相似文献
23.
Bhattacharjee S Chakrabarty S Maity S Kar S Thakur P Bhattacharyya G 《Water research》2003,37(16):3954-3966
Adsorption of water soluble lead on polymetallic sea nodule has been studied in detail. Complete decontamination of lead is possible by appropriate sea nodule dosing. Adsorption is also dependent on pH and best adsorption is achieved at pH 6. Beyond pH 6, the desorption of lead from sea nodule surface is practically zero. Residual metal concentrations in the filtrate after adsorption is negligible. Both Freundlich and Langmuir isotherms may reasonably explain adsorption of lead on sea nodule. Chemically bound moisture plays a very crucial role in lead adsorption. Lead adsorptive capability of sea nodule is practically destroyed when calcined at a temperature of 900 degrees C. Lead loading capacity of sea nodule has been estimated at 440 mg of lead per gram of sea nodule. The performance of sea nodule as a lead adsorbent has been successfully tested over six simulated lead contaminated water systems. Lead loading capacity of sea nodule compares favorably with other adsorbents like activated carbon, ion exchange resin, anionic clay, granulated blast furnace slag and natural and treated zeolites. 相似文献
24.
Fei Su William Hwang Arindam Mukherjee Krishnendu Chakrabarty 《Journal of Electronic Testing》2007,23(2-3):219-233
Microfluidics-based biochips are soon expected to revolutionize biosensing, clinical diagnostics and drug discovery. Robust off-line and on-line test techniques are required to ensure system dependability as these biochips are deployed for safety-critical applications. Due to the underlying mixed-technology and mixed-energy domains, biochips exhibit unique failure mechanisms and defects. We first relate some realistic defects to fault models and observable errors. We next set up an experiment to evaluate the manifestations of electrode-short faults. Motivated by the experimental results, we present a testing and diagnosis methodology to detect catastrophic faults and locate faulty regions. The proposed method is evaluated using a biochip performing real-life multiplexed bioassays. 相似文献
25.
Viviane A. Klemmer Nupur Khera Barbara M. Siegenthaler Indranil Bhattacharya Franz E. Weber Chafik Ghayor 《International journal of molecular sciences》2021,22(20)
The human skeleton is a dynamic and remarkably organized organ system that provides mechanical support and performs a variety of additional functions. Bone tissue undergoes constant remodeling; an essential process to adapt architecture/resistance to growth and mechanical needs, but also to repair fractures and micro-damages. Despite bone’s ability to heal spontaneously, certain situations require an additional stimulation of bone regeneration, such as non-union fractures or after tumor resection. Among the growth factors used to increase bone regeneration, bone morphogenetic protein-2 (BMP2) is certainly the best described and studied. If clinically used in high quantities, BMP2 is associated with various adverse events, including fibrosis, overshooting bone formation, induction of inflammation and swelling. In previous studies, we have shown that it was possible to reduce BMP2 doses significantly, by increasing the response and sensitivity to it with small molecules called “BMP2 enhancers”. In the present study, we investigated the effect of N-Vinyl-2-pyrrolidone (NVP) on osteoblast and osteoclast differentiation in vitro and guided bone regeneration in vivo. We showed that NVP increases BMP2-induced osteoblast differentiation and decreases RANKL-induced osteoclast differentiation in a dose-dependent manner. Moreover, in a rabbit calvarial defect model, the histomorphometric analysis revealed that bony bridging and bony regenerated area achieved with NVP-loaded poly (lactic-co-glycolic acid (PLGA) membranes were significantly higher compared to unloaded membranes. Taken together, our results suggest that NVP sensitizes BMP2-dependent pathways, enhances BMP2 effect, and inhibits osteoclast differentiation. Thus, NVP could prove useful as “osteopromotive substance” in situations where a high rate of bone regeneration is required, and in the management of bone diseases associated with excessive bone resorption, like osteoporosis. 相似文献
26.
Pallavi Mukherjee Chaitali Chanda Moumita Bhaumik Madhurima Ghosh Jaweria Sharmin Poulami Datta Srimoyee Banerjee Parthasarathi Barat Ashoke Ranjan Thakur Lalit Mohan Gantayet Indranil Mukherjee Shaon Ray Chaudhuri 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2018,93(5):1279-1289
27.
Devendrasinh Darbar M.R. Anilkumar Vijayaraghavan Rajagopalan Indranil Bhattacharya Hendry Izaac Elim T. Ramakrishnappa F.I. Ezema Rajan Jose M.V. Reddy 《Ceramics International》2018,44(5):4630-4639
Optimization of electrodes for charge storage with appropriate processing conditions places significant challenges in the developments for high performance charge storage devices. In this article, metal cobaltite spinels of formula MCo2O4 (where M = Mn, Zn, Fe, Ni and Co) are synthesized by oxalate decomposition method followed by calcination at three typical temperatures, viz. 350, 550, and 750 °C and examined their performance variation when used as anodes in lithium ion batteries. Phase and structure of the materials are studied by powder x-ray diffraction (XRD) technique. Single phase MnCo2O4,ZnCo2O4 and Co3O4 are obtained for all different temperatures 350 °C, 550 °C and 750 °C; whereas FeCo2O4 and NiCo2O4 contained their constituent binary phases even after repeated calcination. Morphologies of the materials are studied via scanning electron microscopy (SEM): needle-shaped particles of MnCo2O4 and ZnCo2O4, submicron sized particles of FeCo2O4 and agglomerated submicron particle of NiCo2O4 are observed. Galvanostatic cycling has been conducted in the voltage range 0.005–3.0 V vs. Li at a current density of 60 mA g?1 up to 50 cycles to study their Li storage capabilities. Highest observed charge capacities are: MnCo2O4 – 365 mA h g?1 (750 °C); ZnCo2O4 – 516 mA h g?1 (550 °C); FeCo2O4 – 480 mA h g?1 (550 °C); NiCo2O4 – 384 mA h g?1 (750 °C); and Co3O4 – 675 mA h g?1 (350 °C). The Co3O4 showed the highest reversible capacity of 675 mA h g?1; the NiO present in NiCo2O4 acts as a buffer layer that results in improved cycling stability; the ZnCo2O4 with long needle-like shows good cycling stability. 相似文献
28.
Tuning of an optimal fuzzy PID controller with stochastic algorithms for networked control systems with random time delay 总被引:1,自引:0,他引:1
An optimal PID and an optimal fuzzy PID have been tuned by minimizing the Integral of Time multiplied Absolute Error (ITAE) and squared controller output for a networked control system (NCS). The tuning is attempted for a higher order and a time delay system using two stochastic algorithms viz. the Genetic Algorithm (GA) and two variants of Particle Swarm Optimization (PSO) and the closed loop performances are compared. The paper shows that random variation in network delay can be handled efficiently with fuzzy logic based PID controllers over conventional PID controllers. 相似文献
29.
A new test-resource-partitioning approach, based on test data compression and on-chip decompression, reduces data volume, decreases testing time, and accommodates slower (less expensive) testers without decreasing test duality 相似文献
30.
Gupta S. Bhattacharya A. Ranga Rao K.S. Chakrabarty A. 《IEEE transactions on instrumentation and measurement》2000,49(1):66-70
This paper presents a simple method for determining the dielectric constant of a solid material. The method consists of measuring the return loss due to a slab of such material inserted into a rectangular waveguide. The dielectric slab presents a discontinuity inside the waveguide, and the electric field at each interface of the slab is described as a summation of weighted sinusoidal basis functions. The scattered magnetic field on either side of the slab is determined using the modal expansion approach. These weights are solved by using the method of moments on the boundary conditions of continuity of the tangential magnetic field at the interfaces. The component of the electric field (scattered) for the dominant TE10 mode can then be determined in terms of these weights, and from this result the reflection coefficient can be theoretically evaluated. A comparison between the experimentally obtained reflection/transmission coefficient and the theoretical values provide a figure for the dielectric constant of the material 相似文献