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11.
    
Summary The results obtained between 1980 and 1985 in a Dutch monitoring programme on the presence of arsenic, cadmium, lead and mercury in meat and organs of swine are presented. For meat, livers and kidneys the median values were, respectively, 0.001, 0.001, and 0.003 mg/kg (fresh weight) for arsenic, 0.002, 0.044, and 0.260 mg/kg for cadmium, 0.01, 0.03, and 0.08 mg/kg for lead and 0.001, 0.002, and 0.005 mg/kg for mercury. No significant changes were observed in the tissue arsenic and mercury levels during the investigated period. A decrease was observed in the cadmium and lead concentrations in livers and kidneys. The provisional Dutch legal limits were exceeded only for lead in one kidney sample. A significant recti linear relation was found between the cadmium concentrations in livers and kidneys. In general the cadmium and lead levels found are comparable with published data, reported from other countries. Compared with data from the literature, the arsenic and mercury concentrations found in the present study are low.
Arsen, Cadmium, Blei und Quecksilber in Fleisch, Leber und Niere von Mastschweinen in den Niederlanden während der Jahre 1980–1985
Zusammenfassung Es wird über die Ergebnisse aus den Jahren zwischen 1980 and 1985 eines holländi-schen Überwachungsprogramms uber das Vorkommen von Arsen, Cadmium, Blei and Quecksilber in Fleisch and Organen von Mastschweinen berichtet. Für Fleisch, Leber and Niere lagen die ermittelten Medianwerte für Arsen bei 0,001 bzw. 0,001 and 0,003 mg/kg (bezogen auf Frischgewicht), für Cadmium bei 0,002 bzw. 0,044 and 0,260 mg/kg, für Blei bei 0,01 bzw. 0,03 and 0,08 mg/kg and für Quecksilber bei 0,001 bzw. 0,002 and 0,005 mg/kg. Die Arsen- und Quecksilbergehalte von Fleisch and Organen zeigten keine signifikante Änderung wahrend dieser Periode. Eine Abnahme wurde bei den Cadmium- and Bleigehalten von Leber and Nieren beobachtet. Die vorläu-figen holländischen gesetzlichen Richtwerte wurden nur für Blei in einer Nierenprobe überschritten. Die Cadmiumgehalte von Niere und Leber sind signifikant miteinander korreliert. Die Cadmium- und Bleigehalte sind im allgemeinen gut vergleichbar mit den Angaben anderer Länder. Die Arsen- und Quecksilbergehalte unserer Untersuchung sind im Vergleich mit den Angaben aus der Literatur niedrig.
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12.
The effects of frozen storage and initial baking time of par‐baked cake on baking loss, volume, moisture, colour and textural properties of cake obtained after thawing and rebaking were investigated. Cakes, par‐baked at 175 °C for 15, 20 and 25 min, were stored at ?18 °C for 3, 6 and 9 months. After storage, par‐baked cakes were thawed and rebaked at 175 °C for 10, 15 and 20 min. Baking loss, moisture content, L and +b colour values, firmness, gumminess and chewiness of the resulting full‐baked cakes were significantly affected by both par‐baking and frozen storage time, while specific volume, cohesiveness, springiness and resilience values were significantly affected by frozen storage time. The increase in the time of frozen storage of the par‐baked cake leads to a decrease in the quality of the rebaked cake, namely an increase of baking loss and cake crumb firmness, and a loss in the moisture content and specific volume. Moisture of cake crumb, L and +b colour values, firmness, gumminess and chewiness significantly increased as the par‐baking time increased. However, regarding baking loss, specific volume, moisture content and textural properties, 3‐month intermediate storage at ?18 °C and 20‐min initial baking time gave the best result among the cakes produced by using the two‐step baking procedure.  相似文献   
13.
The parameters of a spectrometer for searching for deeply bound pionic states of xenon are presented. The main component of the spectrometer is a multilayer semiconductor telescope based on high-purity germanium detectors. A technique for calibrating the spectrometer and measuring its energy resolution using reactions p(d, 3He)π0 and 14N(d, 3He)13C is described. The energy resolution of the setup is shown to be 0.85 MeV for 3He ions with an energy of ~360 MeV.  相似文献   
14.
Imipenem and amikacin, alone and in combination, were investigated for their postantibiotic effect (PAE) on Pseudomonas aeruginosa. Four clinical strains of P. aeruginosa in the logarithmic phase of growth were exposed for 1 h to antibiotics, alone and in combination. Recovery periods of test cultures were evaluated after dilution using viable counting. Imipenem produced a PAE ranging from 0.7 to 1.55 h. Similar PAEs were induced by amikacin (ranging from 0.65 to 2 h). In combination, imipenem and amikacin produced as a final PAE (ranging from 1.6 to 2.65 h), a rough mathematical sum of the individual effects. The finding of this study may have important implications for the timing of doses during therapy with antimicrobial combinations.  相似文献   
15.
The water sorption and diffusion in (reduced) graphene oxide‐alginate composites of various compositions is analyzed. Water sorption of sodium alginate can be significantly reduced by the inclusion of graphene oxide sheets due to the formation of an extensive hydrogen bonding network between oxygenated groups. Crosslinking alginate with divalent metal ions and the presence of reduced graphene oxide can further improve the swelling resistance due to the strong interactions between metal ions, alginate, and filler sheets. Depending on conditions and composition, the overall water barrier properties of alginate composites improve upon (reduced) graphene oxide filling, making them attractive for moisture barrier coating applications. Water sorption kinetics in all alginate composites indicate a non‐Fickian diffusion process that can be accurately described by the Variable Surface Concentration model. In addition, the water barrier properties of sodium alginate‐graphene oxide composites can be adequately predicted using a simple model that takes the orientational order of filler sheets and their effective aspect ratio into account.

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A zero-degree spectrometer for tagging η mesons on the CELSIUS/WASA facility is described, and its characteristics are presented. Tagging of η mesons is performed by detecting 3He ions produced by reaction pd3Heη close to the production threshold. The low background level (<2%) is in good agreement with the data obtained earlier on the SATURNE accelerator.  相似文献   
18.
Neurotoxic effects are of such breadth and complexity that functional biomarkers (behavioral tests) that integrate many areas of the nervous system predominate in human neurotoxicology research. The increasing distribution of chemical and other manufacturing throughout the world, particularly in developing nations, suggests the acute need to develop biomarkers for chemical exposures and effects that can be employed internationally. A language-free method for training performance on behavioral tests is described, which holds promise for international research that circumvents the vagaries of translation. Four behavioral tests were administered to 74-114 adult US subjects. Procedures, collectively termed shaping, produced effective performance on three tests [Symbol Digit, Vigilant Attention Test (VAT), Digit Span Forward and Backward], and produced appropriate but unacceptably slow performance in initial testing on the Simple Reaction Time test. Effective performance on the Symbol-Digit test also was produced by shaping instruction, without assistance from examiners, in small groups of residents of Taipei (Taiwan) and US children between the ages of 5 and 16.  相似文献   
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20.
Optical traps are commonly constructed with high-numerical-aperture objectives. Oil-immersion objectives suffer from spherical aberrations when used for imaging in aqueous solutions. The effect of spherical aberrations on trapping strength has been modeled by approximation, and only a few experimental results are available in the case of micrometer-sized particles. We present an experimental study of the dependence of lateral and axial optical-trap stiffness on focusing depth for polystyrene and silica beads of 2 microm diameter by using oil- and water-immersion objectives. We demonstrate a strong depth dependence of trap stiffness with the oil-immersion objective, whereas no depth dependence was observed with the water-immersion objective.  相似文献   
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