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91.
SE Browne AC Bowling U MacGarvey MJ Baik SC Berger MM Muqit ED Bird MF Beal 《Canadian Metallurgical Quarterly》1997,41(5):646-653
The etiology of the selective neuronal death that occurs in Huntington's disease (HD) is unknown. Several lines of evidence implicate the involvement of energetic defects and oxidative damage in the disease process, including a recent study that demonstrated an interaction between huntingtin protein and the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Using spectrophotometric assays in postmortem brain tissue, we found evidence of impaired oxidative phosphorylation enzyme activities restricted to the basal ganglia in HD brain, while enzyme activities were unaltered in three regions relatively spared by HD pathology (frontal cortex, parietal cortex, and cerebellum). Citrate synthase-corrected complex II-III activity was markedly reduced in both HD caudate (-29%) and putamen (-67%), and complex IV activity was reduced in HD putamen (-62%). Complex I and GAPDH activities were unaltered in all regions examined. We also measured levels of the oxidative damage product 8-hydroxydeoxyguanosine (OH8dG) in nuclear DNA, and superoxide dismutase (SOD) activity. OH8dG levels were significantly increased in HD caudate. Cytosolic SOD activity was slightly reduced in HD parietal cortex and cerebellum, whereas particulate SOD activity was unaltered in these regions. These results further support a role for metabolic dysfunction and oxidative damage in the pathogenesis of HD. 相似文献
92.
A method was developed to determine the extent of hydrogenation of the Δ15 double bond which occurs during partial catalytic
hydrogenation of soybean oil. A linear relationship was found to exist between the linolenate content of commonly occurring
C18 unhydrogenated oils (containing no tetraene) and the propanal resulting from their ozonization reduction. The amount of propanal
so produced is directly related to the amount of Δ15 double bond in these oils, as well as in hydrogenated soybean oils. Soybean
oil was treated with ozone in carbon tetrachloride at —20 C and then reduced with triphenylphosphine. The ozonized-reduced
sample was injected into a gas chromatograph, operated at 170C and equipped with a 12 ft × 1/4 in. column of 100/ 120 mesh
porous polymer beads. The propanal peak was identified and its area used as a measure of the fatty acids containing Δ15 double
bonds in unhydrogenated soybean and other oils of known linolenate content. A nearly stoichiometric amount of propanal results
from ozonizing, reducing and chromatographing soybean oil as shown by comparison with a standard mixture of propanal and carbon
tetrachloride. The relative standard deviation for the method is ±4.4%. We have also found this method applicable to other
oils containing the omega-3 double bond.
Presented at the AOCS-AACC Meeting, Washington, D.C., March, 1968.
No. Utiliz, Res. Div., ARS, USDA. 相似文献
93.
K. J. Moulton D. J. Moore R. E. Beal 《Journal of the American Oil Chemists' Society》1969,46(12):662-666
In pilot-plant tests, the linolenate content of soybean oil was reduced to less than 1% without increasing the saturates,
by hydrogenation to an IV of about 115 with an active copper-chromite catalyst. The linolenate-linoleate selectivity ratio
(KLe/KLo) was from 9 to 12. Several commercial copper-chromite catalysts were used in hydrogenation tests. The activities of four
of five commercial catalysts tested were improved to various degrees by heating in air at 350 C (one was inactive both before
and after heating). Examination by differential thermal analysis (DTA) of each catalyst, just as received and then after being
heated at 350 C, demonstrated that heating greatly diminished or removed peak areas from the DTA curve. Studies made with
one commerical copper-chromium-barium catalyst showed that heating the catalyst was also necessary to gain maximum linolenate-linoleate
selectivity in hydrogenating soybean oil.
Presented at the AOCS Meeting, New Orleans, May 1967.
No. Utiliz. Res. Dev. Div., ARS, USDA. 相似文献
94.
R. E. Beal R. A. Eisenhauer V. E. Sohns 《Journal of the American Oil Chemists' Society》1965,42(12):1115-1119
In an attempt to lower processing costs of producing cyclic fatty acids by a high-temperature alkali treatment, water was
tested as the reaction solvent instead of ethylene glycol, previously used. Based on extensive tests in a high-pressure autoclave,
saturated cyclic (cyclohexanoic) fatty acids were produced under economic reaction conditions, including a temperature of
about 300C; a 4:1 solvent ratio and 50% excess sodium hydroxide catalyst. The lower yield of saturated cyclic fatty acids
by the water process is more than offset by the fewer steps and reduced evaporation costs.
Presented at the AOCS Meeting, Chicago, Ill., 1964.
A laboratory of the No. Utiliz. Res. & Dev. Div., ARS, USDA. 相似文献
95.
In the design of high-perveance electron beam devices, it is necessary to evaluate the effects of the self-fields on the beam trajectories as well as the effects of any external electromagnetic fields that may be present. This paper describes a means whereby the self-consistent solution of Poisson's equation, the relativistic equations of electron motion, and the equation of charge continuity, all subject to specified boundary conditions, are determined by means of a digital computer program. In particular the method is applied to the case of an axially symmetric, solid-beam electron gun where the electrons are emitted with zero initial velocity from a spacecharge-limited cathode. 相似文献
96.
The vibrational modes of the -NO2 group in more than fifty energetic compounds containing the C-nitro and N-nitro functionalities were observed and then calculated in optimized structures using density functional theory (B3LYP/6-31+G*). The trends in the symmetric and asymmetric stretches and scissor and out-of-plane deformations were explained by these calculations. A previously unreported correlation was found between the nitro group internal bonding angle and its asymmetric stretching frequency. The concept of meta and ortho/para directing groups was applicable to the trends in coupled motions in the nitroaromatic compounds. Both the scissor motion of C-NO2 groups and the out-of-plane deformation of N-NO2 groups were found to be virtually insensitive to the remainder of the molecule. These findings may be useful in analytical methods of explosive detection based on their infrared (IR) spectra. 相似文献
97.
98.
R. W. Beal C. D. Incarvito B. J. Rhatigan A. L. Rheingold T. B. Brill 《Propellants, Explosives, Pyrotechnics》2000,25(6):277-283
The molecular structures of five furazan compounds in which two amino‐ or 1 nitro‐substituted furazan rings are bridged by azo, azoxy or hydrazo groups were determined by single crystal X‐ray crystallography. These are diaminoazofurazan, diaminoazoxyfurazan, dinitroazoxyfurazan, diaminohydrazofurazan and dinitrohydrazofurazan. The structures are compared to those previously reported on dinitroazofurazan, aminonitroazoxyfurazan and another polymorph of diaminoazoxyfurazan. 相似文献
99.
A Desktop Analysis of Potable Water Savings from Internally Plumbed Rainwater Tanks in South-East Queensland,Australia 总被引:3,自引:1,他引:2
A methodology for the estimation of household potable water saving due to internally plumbed rainwater tanks (IPT) is presented in this paper. The methodology is based on a pairwise comparison of household water billing data between homes with IPT and without rainwater tanks (No Tank). These savings were compared with estimations using measured end use data and rainwater demand predictions using the Rainwater TANK model. The paper describes the application of this methodology to a case study in the south-east Queensland (SEQ) region of Australia. There was a significant reduction in mains water consumption for IPT properties in all regions studied in SEQ. Water reductions from mains supplies varied markedly across regions with mean values ranging from 20 to 95 kL/hh/y with an average mean of 50 kL/hh/y. Median water consumption values, ranged in mains water reductions from 28 to 52 kL/hh/y, with an average median of 40 kL/hh/y. Considering both measures an average water saving between 40 and 50 kL/hh/y can be expected from internally plumbed rainwater tanks. Water restrictions appear to have a strong influence on estimated reductions in mains water use. In regions where water restrictions were severe, water consumption was less varied between No Tank and IPT homes with a consequent reduction in estimated savings observed. Recommendations for further work include a survey to capture confounding factors that could not be fully controlled in the desktop study and a controlled pairwise experiment to monitor water consumption from raintanks. 相似文献
100.
Trougakos John P.; Jackson Christine L.; Beal Daniel J. 《Canadian Metallurgical Quarterly》2011,96(2):350
We used an experimental design to examine the intrapersonal and interpersonal processes through which neutral display rules, compared to positive display rules, influence objective task performance of poll workers and ratings provided by survey respondents of the poll workers. Student participants (N = 140) were trained to adhere to 1 of the 2 display rule conditions while delivering opinion surveys to potential patrons of an organization during a 40-min period. Results showed that, compared to positive display rules, neutral display rules resulted in less task persistence and greater avoidance behavior. These effects were mediated through a greater use of expression suppression. In addition, neutral display rules resulted in less positive respondent mood, which accounted for lower ratings of service quality and of overall favorability attitudes toward the sponsoring organization. The importance and ubiquity of neutral display rules are discussed, given the potential for positive and negative consequences at work. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献