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31.
This paper explores intra-state disparity in access to electricity and examines the determinants of electrification at the village level in Bihar, one of the underdeveloped states in India. Our field survey of 80 villages in 5 districts conducted in 2008–09 found that 48 villages (60%) are electrified when using the definition of electrification that a village is electrified if any one household in the village is connected to electricity. In the processes of electrification, approximately 40% of villages have been electrified in recent years. The econometric analyses demonstrate that location is the most important determinant of a village's electricity connection. Another important finding is that with the rapid progress of rural electrification under the recent government program and the tendency to connect the villages that are easily accessible, the collective bargaining power of the village, which used to significantly affect the process of electrification, has lost influence. This adversely affects remote villages. In order to extend electricity supplies to remote and geographically disadvantaged villages, the government needs to consider other options for sustainable electricity supply, such as decentralized distribution of electricity rather than the conventional connection through the national/local grids.  相似文献   
32.
Three types of fullerene (C60)‐end‐capped poly(4‐diphenylaminostyrene) (C60–PDAS) and poly(4‐diphenylaminostyrene) (PDAS) blends were prepared to investigate their potential as bipolar polymer semiconductors. The concentration of C60 in the C60–PDAS/PDAS blends strongly affected the hole and electron drift mobility values; the hole drift mobility decreased with an increase in the C60 concentration. However, the electron drift mobility increased with an increase in the C60 concentration. The hole and electron drift mobility values were almost the same for the 1/2 C60–PDAS/PDAS blend; therefore, this polymer blend was thought to be a bipolar polymer semiconductor. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
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The levels of fatty acids and their distribution were determined in spores from twenty-five strains of Bacillus natto isolated from a fermented soybean food, natto, or subcultured from the culture collection. The major fatty acid components of spores, consisting of about 80 to 90% of the total, were anteiso-C15, anteiso-C17, iso-C15 and iso-C17; the other fatty acids, at a level of 10 to 20% of the total, were iso-C14, iso-C16, n-C14, n-C16 and n-C18. The amount of fatty acid in spores was highest with anteiso-C15, followed in order by iso-C15. In addition to the nine fatty acids, some of the strains produced six extra fatty acids, three branched (anteiso-C13, iso-C12 and iso-C13) and three normal (n-C12, n-C15 and n-C17).  相似文献   
36.
The time-averaged 1H n.m.r. spectra of ethylene-propylene-dicyclopentadiene, ethylene-propylene-ethylidene norbornene and isobutylene-isoprene copolymers were measured. Assignments of the olefinic resonances were carried out by comparing the spectra with those of each homopolymer and strarting monomers. The concentration of the olefinic unit in copolymer was determined by measuring the intensity ratio between the olefinic proton signal and the signal of trichloroethylene which was added as an internal standard of intensity measurements. The concentrations of unsaturation in copolymers determined by using the iodine-mercuric acetate method were proportional to those determined by the n.m.r. method. The accuracy and precision of the n.m.r. measurements were shown to be better than 10% for a mixture of polyisobutylene and polyisoprene containing 1.24 mol % of unsaturation as a model compound of isobutylene-isoprene copolymer.  相似文献   
37.
A rapid analytical method for the simultaneous determination of carbamate pesticides in processed foods was established by liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS). The pesticides were extracted from samples with acetonitrile using accelerated solvent extract equipment, except for the fine powder type spices, which were extracted in an ultrasonic bath. The crude extract was cleaned up with a multi-solvent GPC column (Shodex Asahipak GF-310 HQ) using acetonitrile as a mobile phase. The eluent from the column at the retention time between 13 to 18 min was concentrated under nitrogen gas and dissolved in a mixture of acetonitrile-water-0.2 mol/L ammonium formate buffer pH 6.0 (10 : 9 : 1). An aliquot was injected into the LC/MS/MS using electrospray ionization (ESI) with acquisition in the positive mode.The recoveries of 29 kinds of pesticide from dried fruits (raisin, prune and mango) and spices (turmeric, masala, sage, thyme and red pepper) fortified at levels of 0.1 and 0.01 microg/g were mostly in the range of 50 to 150% and those from soybean paste and soy sauce fortified at 0.01 microg/g were 46.9 to 122.6% (C.V. 3.8 to 37.6%), except for 4 kinds of pesticide. The determination limits (S/N> or =10) corresponded to 0.001 to 0.05 mug/g of the pesticides in red pepper.  相似文献   
38.
A simultaneous determination of veterinary drugs in livestock food and seafood using liquid chromatography with tandem mass spectrometry (LC/MS/MS) was developed. Veterinary drugs were extracted with 95% acetonitrile. The solution was passed through a Florisil column, and the solvent was replaced with phosphate buffer. The extract was charged on a Sep-Pak Plus C(18) mini-column and divided into 40% methanol eluate fraction and 70% acetonitrile eluate fraction. Test solutions were analyzed by LC/MS/MS with gradient elution. By using this method, 37 kinds of veterinary drugs were obtained with over 60% recovery, and quantitation was possible in cattle muscle, egg and fish. This method was inapplicable to 28 kinds of veterinary drugs. Although quantitation was not achieved, 42 other kinds of veterinary drugs can be screened. Since the limit of quantitation for this method is less than the provisional limit in general, it is useful as a screening method in residual analysis of veterinary drugs.  相似文献   
39.
A simple and convenient analytical method for the determination of acrylamide in processed foods was established. Acrylamide was extracted with water in an ultrasonic bath. The extract was passed through an OASIS HLB cartridge and the eluate was injected into the HPLC system using a column-switching technique. The HPLC system consisted of two pumps, two 6-port-2-position valves, two columns and a UV detector. At first, the sample solution was chromatographed on an ODS column with a mobile phase of water, then the flow of the mobile phase was switched using a 6-port-2-position valve, and the acrylamide peak fraction was introduced into an aqueous gel permeation column (analytical column). The fraction was chromatographed again on the analytical column with a mobile phase of water, and the eluate was monitored with a UV detector (205 nm). The recoveries of acrylamide from potato chips, fried potato, croquette and instant noodle fortified at levels of 50 to 1,000 micrograms/kg were 93.1 to 101.5% and the coefficient of variation was 1.5 to 5.2%. The detection limit corresponded to 10 micrograms/kg in processed foods. Forty-six samples, potato chips (11), fried potato (10), croquette (20) and instant noodle (5), were analyzed by this method. The acrylamide level was 67-4,499 micrograms/kg for potato chips, 125-1,183 micrograms/kg for fried potato, nd-255 micrograms/kg for croquette and nd-151 micrograms/kg for instant noodle.  相似文献   
40.
This blinded, single center study prospectively compares exercise electron beam computed tomography (EBCT) with stress technetium-99m (Tc-99m) sestamibi single-photon emission computed tomography (SPECT) in 33 patients undergoing coronary angiography for evaluation of chest pain. Patients undergoing routine cardiac catheterization for the diagnosis of chest pain were imaged at rest using EBCT. Patients exercised on a semi-supine ergometer, and exercise EBCT was immediately followed by injection of Tc-99m sestamibi for assessment of myocardial ischemia. At peak exercise, Tc-99m SPECT, followed immediately by nonionic contrast material, was injected intravenously to directly compare these 2 imaging techniques. Patients were reimaged with Tc-99m SPECT at rest 24 to 48 hours after stress. Exercise EBCT, which was analyzed using a global ejection fraction measure, had a sensitivity of 81% and a specificity of 76%, compared with angiography. Using the development of a new regional wall motion abnormality as evidence of obstructive coronary artery disease (CAD), EBCT yielded a specificity of 100% and a sensitivity of 88%. Reversible perfusion defects identified by SPECT, as evidence of obstructive CAD, revealed a sensitivity of 75% and a specificity of 71%. The specificity of regional wall motion analysis by EBCT was significantly better than SPECT (p <0.01) in this population. This study demonstrates regional wall motion assessed by EBCT to be as sensitive and more specific than SPECT myocardial perfusion imaging in identifying obstructive CAD as defined by angiography.  相似文献   
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