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101.
The identification, analysis, and occurrence in U.S. automobile original finishes (1974-1989) of Nickel Titanate (yellow) and Chrome Titanate (yellow-orange) are described in this report. The titanate pigments are based on the rutile (titanium dioxide) structure and there are only minor differences between the infrared absorptions of rutile and the titanates. Titanate pigment absorptions in paint spectra can thus be easily mistaken for those of rutile. Each of the titanates, however, contains two elements in addition to titanium that can serve to distinguish them using elemental analyses. Fourier transform infrared (4000-220 cm(-1)) and X-ray fluorescence instruments were used in combination for the in situ analysis of the titanates. In addition to titanium, nickel, and antimony, the three main detectable elements comprising Nickel Titanate, all of the commercial products of this pigment that were examined also contained impurities of zirconium, niobium, and usually lead. These elements were also detected in most of the monocoats in which Nickel Titanate was identified, as well as in the Chrome Titanate pigments, and the zirconium to niobium ratio was found to exhibit a wide variation. Nickel Titanate is a relatively common pigment that was identified in nearly three dozen U.S. automobile yellow nonmetallic monocoats (1974-1989), while Chrome Titanate appears to have been used in only a few yellow and orange nonmetallic monocoats. The use of the titanate pigments likely increased after this time period as they were replacements for lead chromate pigments (last used in a U.S. automobile original finish in the early 1990s), and are more amenable for use in basecoat/clearcoat finishes than in monocoats. Minor distortions of the infrared absorptions of rutile, anatase, and the titanates obtained using accessories with diamond windows were noted, and their origins are discussed.  相似文献   
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103.
We experienced an autopsy case in which a 53-year-old woman committed suicide by ingesting allegedly a certain agricultural chemical. The blood and stomach contents, after extraction with acetonitrile and chloroform, were subjected to analysis by gas chromatography (GC)/negative ion chemical ionization (CI) mass spectrometry (MS). By total ion monitoring in the negative CI mode, a large peak appeared. The mass spectrum of the peak showed a strong anion at m/z 157, suggesting the presence of an organophosphorus pesticide. By measuring its spectrum in the positive electron impact (EI) mode, it was identified as malathion. The selected ion monitoring in the negative CI mode showed that the malathion peak was not interfered with by any impurities, and its background was very low. The sensitivity in the negative CI mode was about 5-10 times higher than that in the positive EI mode. Our data show that the GC/negative ion CI MS is useful for both screening and sensitive quantitation of organophosphorus pesticides.  相似文献   
104.
A 37-year-old woman died after 18 days from her starting to take sulindac for low back pain. Based on her clinical course and the autopsy findings, the cause of her death was Lyell syndrome (toxic epidermal necrolysis) induced by sulindac. This case is described together with the legal aspects of medical malpractice to which it gave rise.  相似文献   
105.
To investigate the effects of very high concentrations of carbon dioxide (CO2) upon the course of respiration and circulation, dogs were allowed to breathe high concentrations of CO2 while intrathoracic pressure, blood pressure (BP) in the femoral artery, electrocardiogram and electroencephalogram readings were registered. The respiratory movements either increased just after inhalation of high concentrations of CO2 and then ceased in 1 min, or decreased and continued for a while according to the concentrations of CO2. The BP showed an initial depression, then returned to the original level, then fell again rapidly or maintained an appreciable level for a while until circulatory breakdown. In the dogs allowed to breathe the gas mixture of 80% CO2 with 20% O2, the respiratory movement ceased in 1 min, and the terminal respirations were seen with the circulatory breakdown after apnoea of several minutes. These findings showed that the cause of death in breathing high concentrations of CO2 is not hypoxia, but the CO2 poisoning.  相似文献   
106.
Positive-ion electron impact (PIEI), positive-ion chemical ionization (PICI) and negative-ion chemical ionization (NICI) mass spectra of 9 carbamate pesticides are presented. In the PIEI mode, the spectra showed small molecular peaks, intense or base peaks due to M - CH3NHCO + H and peaks at m/z 58 due to CH3NHCO. In the PICI mode, peaks due to M + H, M + C2H5, M - CH3NHCO + 2H, CH3NHCO(m/z 58) and M-28 appeared. The cations at m/z 58 found in both PIEI and PICI modes seem very useful for screening of a carbamate. In the NICI mode, the spectra showed peaks due to M - CH3NHCO and characteristic anions appearing at mass numbers higher than molecular ones, which were probably due to dimerization of [M - CH3NHCO]-followed by hydrogen attachment. Carbamates, which had been added to urine, plasma, whole blood, the liver, kidney and brain, could be rapidly isolated by use of Sep-Pak C18 cartridges with chloroform as an elution solvent. They could be detected by wide-bore capillary gas chromatography with a SPB-5 column, with satisfactory separation from impurities in their underivatized forms.  相似文献   
107.
A rapid and simple method of utilizing thin-layer chromatography (TLC) and pyrolysis gas chromatography (PyGC) for the identification and determination of methylbenactyzium bromide in human urine was studied in this report. Methylbenactyzium bromide was extracted from urine with ODS-cartridge (Sep-Pak C18), then spotted onto a silica gel 60 F254 TLC plate. After development, the separated spot of methylbenactyzium bromide was scraped and wrapped with a ferromagnetic foil without extraction by any organic solvents. The sample was applied into PyGC analysis. The optimum temperature for pyrolysis was 590 degrees C. The main degradation product of methylbenactyzium bromide was identified as diphenylmethane in this procedure by gas chromatography/mass spectrometry (GC/MS). A calibration graph prepared by absolute calibration method showed a good linearity over the concentration range of 1-75 micrograms/spot for methylbenactyzium bromide. The coefficient of variation obtained for eleven replicate analyses of the 3 micrograms/spot of standard methylbenactyzium bromide was 3.8%. The detection limit of this compound by this procedure was 0.1 micrograms/spot.  相似文献   
108.
Although Asia has experienced civil war about as often as Sub-SaharanAfrica during the post-World War II era, there have been fewsystematic investigations into the determinants of civil warin Asia. This article examines the effects of trade opennessand economic development on the onset of civil war in post-colonialAsia, controlling for political, demographic, and geographicfactors. Analyzing data on post-colonial Asian states between1950 and 1992, we find that the onset of civil war is less likelywith increased trade openness. However, when taking into accountinteraction between trade openness and economic development,we discover that increased trade openness reduces the likelihoodof civil war onset significantly only in the context of higheconomic development. This result is robust with different modelspecifications.  相似文献   
109.
The 1990s saw the introduction of significantly new types of paint binder chemistries into the automotive finish coat market. Considering the pronounced changes in the binders that can now be found in automotive paints and their potential use in a wide variety of finishes worldwide, the Paint Subgroup of the Scientific Working Group for Materials (SWGMAT) initiated a validation study to investigate the ability of commonly accepted methods of forensic paint examination to differentiate between these newer types of paints. Nine automotive paint systems typical of original equipment applications were acquired from General Motors Corporation in 1992. They consisted of steel panels coated with typical electrocoat primers and/or primer surfacers followed by a black nonmetallic base coat and clear coat. The primary purpose of this study was to evaluate the discrimination power of common forensic techniques when applied to the newer generation original automotive finishes. The second purpose was to evaluate interlaboratory reproducibility of automotive paint spectra collected on a variety of Fourier transform infrared (FT-IR) spectrometers and accessories normally used for forensic paint examinations. The results demonstrate that infrared spectroscopy is an effective tool for discriminating between the major automotive paint manufacturers' formulation types which are currently used in original finishes. Furthermore, and equally important, the results illustrate that the mid-infrared spectra of these finishes are generally quite reproducible even when comparing data from different laboratories, commercial FT-IR instruments, and accessories in a "real world," mostly uncontrolled, environment.  相似文献   
110.
We devised a simple DNA extraction procedure suitable for STR typing of urine sample. Use of a commercially available DNA/RNA extraction kit equipped with a silica-gel-based membrane made it possible to omit the recovery of urinary nucleated cells by sedimentation before the extraction. Successful genotyping of the TH01, HumTPO and multiplex STRs was achieved using aliquots of urine as small as 100 microL. Furthermore, application of this DNA extraction procedure to frozen urine samples provided STR allele results comparable to results obtained from fresh samples. Therefore, this extraction procedure is considered to be effective for STR typing of urine samples in both the frozen and aqueous state. Furthermore, addition of sodium azide to fresh urine samples prolonged their storage duration even at room temperature.  相似文献   
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