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71.
72.
The future economic development trajectory for India is likely to result in rapid and accelerated growth in energy demand, with expected shortages. Many of its current policies and strategies are aimed at the improvement and possible maximization of energy production from the renewable sector. It is also clear that while energy-conservation and energy-efficiency can make an important contribution in the national energy strategy, renewable energies will be essential to the solution and are likely to play an increasingly important role for the growth of grid power, providing energy access, reducing consumption of fossil fuels, and helping India pursue its low carbon progressive pathway. However, most of the states in India, like the northernmost State of Jammu and Kashmir (J&K), have experienced an energy crisis over a sustained period of time. As India intends to be one of the emerging powers of the 21st century, it has to embark upon with these pressing issues in a more sustainable manner and accordingly initiate various renewable energy projects within these states. This paper will provide a broad-spectrum view about the energy situation within J&K and will highlight the current policies along with future strategies for the optimal utilization of renewable energy resources.  相似文献   
73.
Metal oxides are well-known potential alternatives to graphite as anode materials of lithium-ion batteries, and they can deliver much higher reversible capacities than graphite even at high current densities. In this study, hexagonal disk-shaped ZnO are synthesized by a facile solution reaction of ZnCl2 and its composite is prepared in the presence of carbon nanotubes (CNTs). The as prepared ZnO/CNT composite has been characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, fourier transform-infrared spectroscopy and Rutherford backscattering spectroscopy. Electrochemical characterization by cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic discharge/charge tests demonstrate that the conversion reactions in ZnO and ZnO/CNT electrodes enable reversible capacity of 478 and 602 mAh g?1, respectively for up to 50 cycles. Our investigation highlights the importance of anchoring of small ZnO particles on CNTs for maximum utilization of electrochemically active ZnO and CNTs for energy storage application in lithium-ion batteries.  相似文献   
74.
75.
Energy usage in Pakistan has increased rapidly in past few years due to increase in economic growth. Inadequate and inconsistent supply of energy has created pressure on the industrial and commercial sectors of Pakistan and has also affected environment. Demand has already exceeded supply and load shedding has become common phenomenon. Due to excessive consumption of energy resources it would become difficult to meet future energy demands. This necessitates proper management of existing and exploration of new energy resources. Energy resource management is highly dependent on the supply and demand pattern. This paper highlights the future demands, production and supply of energy produced from natural gas based on economic and environmental constraints in Pakistan with special emphasis on management of natural gas. An attempt has been made by proposing a suitable course of action to meet the rising gas demand. A mechanism has been proposed to evaluate Pakistan's future gas demand through quantitative analysis of base, worst and best/chosen option. CO2 emission for all cases has also been evaluated. The potential, constraints and possible solutions to develop alternative renewable energy resources in the country have also been discussed. This work will be fruitful for the decision makers responsible for energy planning of the country. This work is not only helpful for Pakistan but is equally important to other developing countries to manage their energy resources.  相似文献   
76.
A new cyclic hexapeptide, baceridin ( 1 ), was isolated from the culture medium of a plant‐associated Bacillus strain. The structure of 1 was elucidated by HR‐HPLC‐MS and 1D and 2D NMR experiments and confirmed by ESI MS/MS sequence analysis of the corresponding linear hexapeptide 2 . The absolute configurations of the amino acid residues were determined after derivatization by GC‐MS and Marfey's method. The cyclopeptide 1 consists partially of nonribosomal‐derived D ‐ and allo‐D ‐configured amino acids. The order of the D ‐ and L ‐leucine residues within the sequence cyclo(‐L ‐Trp‐D ‐Ala‐D ‐allo‐Ile‐L ‐Val‐D ‐Leu‐L ‐Leu‐) was assigned by total synthesis of the two possible stereoisomers. Baceridin ( 1 ) was tested for antimicrobial and cytotoxic activity and displayed moderate cytotoxicity (1–2 μg mL?1) as well as weak activity against Staphylococcus aureus. However, it was identified to be a proteasome inhibitor that inhibits cell cycle progression and induces apoptosis in tumor cells by a p53‐independent pathway.  相似文献   
77.
Nisar  H. Choi  T.-S. 《Electronics letters》2006,42(24):1384-1385
Suggested is a simple scheme that includes spatio-temporal neighbourhood information for obtaining better estimates of motion vectors. The estimated motion vector is chosen as initial search centre which is found closer to the global minimum. The final search pattern is adaptive and is based on the direction of the predicted motion vector. Experimental results show that the proposed algorithm enhances the accuracy of the predicted image and reduces the computational requirement compared to other approaches  相似文献   
78.
ABSTRACT

Non-isothermal thermogravimetry (Tg) and derivative thermogravimetry (DTG) studies are reported on a Pakistan lignite and Pakistan subbituminous coal. The burning profiles of the samples shows multi-peak configuration which is indicative of the heterogeneity of organic matter. The volatile matter profiles of these samples are characterized by rate of weight loss.  相似文献   
79.
We investigated the concentrations and profiles of 16 priority polycyclic aromatic hydrocarbons (PAHs) in various grilled and smoked foods and estimated the dietary exposure of Kuwaiti children, adolescent and adult populations. Results indicated that non-carcinogenic PAHs were present at high proportions (60–100%) with phenanthrene showing the highest mean concentration (54.9 μg kg?1, 37.1% of the total PAH concentrations). Among the genotoxic PAHs (PAH8), chrysene (4.88 μg kg?1, 3.29%) and benz[a]anthracene (2.27 μg kg?1, 1.53%) showed the highest mean values. Meat tikka contained the highest mean concentrations of benzo[a]pyrene (BaP) (2.48 μg kg?1), total genotoxic PAHs (42.9 μg kg?1), total PAHs (ΣPAHs) (648 μg kg?1) and total benzo[a]pyrene equivalents (ΣBaPeq) (6.02 μg kg?1). High levels of genotoxic PAHs were detected in grilled vegetables (21.1 μg kg?1), shish tauk (20.5 μg kg?1) and whole grilled chicken (20.3 μg kg?1) samples. However, meat and chicken shawerma samples had low levels of PAH8. Meat tikka (437 ng/day, 641 ng/day), whole grilled chicken (160 ng/day, 241 ng/day), grilled vegetables (120 ng/day, 166 ng/day), meat burger (114 ng/day, 92.7 ng/day) were the major contributors to the daily intake of PAH8 in children/adolescent and adult populations, respectively. The total mean dietary intakes for children/adolescents and adults for BaP (8.09 ng/day, 9.20 ng/day), PAH8 (84.2 ng/day, 95.7 ng/day), ∑PAHs (974 ng/day, 1108 ng/day) and ∑BaPeq (14.8 ng/day, 16.8 ng/day) were comparable. Cancer risks for Kuwaiti children/adolescents and adults from dietary intake of ΣBaPeq from the animal-origin foods were determined to be 2.63/107 and 9.3/107, respectively.  相似文献   
80.
An emerging definition of the fractal-fractional operator has been used in this study for the modeling of Casson fluid flow. The magnetohydrodynamics flow of Casson fluid has cogent in a channel where the motion of the upper plate generates the flow while the lower plate is at a static position. The proposed model is non-dimensionalized using the Pi-Buckingham theorem to reduce the complexity in solving the model and computation time. The non-dimensional fractal-fractional model with the power-law kernel has been solved through the Laplace transform technique. The Mathcad software has been used for illustration of the influence of various parameters, i.e., Hartman number, fractal, fractional, and Casson fluid parameters on the velocity of fluid flow. Through graphs and tables, the results have been implemented and it is shown that the boundary conditions are fully satisfied. The results reveal that the flow velocity is decreasing with the increasing values of the Hartman number and is increasing with the increasing values of the Casson fluid parameter. The findings of the fractal-fractional model have elucidated that the memory effect of the flow model has higher quality than the simple fractional and classical models. Furthermore, to show the validity of the obtained closed-form solutions, special cases have been obtained which are in agreement with the already published solutions.  相似文献   
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