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1.
This work reports on dyeing of nylon/elastane fabric with water-soluble phthalocyanines ( 1-4 ) bearing quinoline 5-sulfonic acid substituents on the peripheral or nonperipheral positions and determining the antibacterial efficiency of the phthalocyanine compounds and the dyed nylon/elastane fabrics. The light, washing, water, perspiration, and rubbing fastness properties of nylon/elastane fabrics dyed with phthalocyanines were also determined. The results showed that all dyed fabrics showed very good wet fastness values. The lightfastness value of the nylon/elastane fabric dyed with phthalocyanine dye ( 1 ) showed a much better value than the others. Also, the antibacterial efficiencies of the dyed nylon fabrics and the dye compounds were investigated against a gram-negative ( Escherichia coli ) and a grampositive ( Staphylococcus aureus ) bacteria by using disc diffusion method. The results showed that the dyed nylon/elastane fabrics and the compounds exhibited antibacterial activities against both bacteria.  相似文献   
2.
Bacillus anthracis is an endospore-forming bacterium that causes inhalational anthrax. Key virulence genes are found on plasmids (extra-chromosomal, circular, double-stranded DNA molecules) pXO1 (ref. 2) and pXO2 (ref. 3). To identify additional genes that might contribute to virulence, we analysed the complete sequence of the chromosome of B. anthracis Ames (about 5.23 megabases). We found several chromosomally encoded proteins that may contribute to pathogenicity--including haemolysins, phospholipases and iron acquisition functions--and identified numerous surface proteins that might be important targets for vaccines and drugs. Almost all these putative chromosomal virulence and surface proteins have homologues in Bacillus cereus, highlighting the similarity of B. anthracis to near-neighbours that are not associated with anthrax. By performing a comparative genome hybridization of 19 B. cereus and Bacillus thuringiensis strains against a B. anthracis DNA microarray, we confirmed the general similarity of chromosomal genes among this group of close relatives. However, we found that the gene sequences of pXO1 and pXO2 were more variable between strains, suggesting plasmid mobility in the group. The complete sequence of B. anthracis is a step towards a better understanding of anthrax pathogenesis.  相似文献   
3.
X-ray and ultraviolet photoelectron spectroscopic results are reported for the interaction of CH3OH with clean polycrystalline Al in the temperature range 110–500 K. Methanol is moleculary chemisorbed at low exposure and low temperature (110 K) followed by condensation at higher exposure. Bonding mechanisms and geometries in the condensed and chemisorbed layers are discussed. The multilayers desorb beginning near 170 K and the chemisorbed layer is converted into a surface methoxide. Room temperature adsorption also leads to formation of the methoxide species which is stable to ~500 K, at which point it decomposes evolving CH4 and leaves the surface oxidized.  相似文献   
4.
The author proves a central limit theorem for the critical super Brownian motion, which leads to a Gaussian random field. In the transient case the limitingfield is the same as that obtained by Dawson (1977). In the recurrent case it is aspatially uniform field. The author also give a central limit theorem for the weightedoccupation time of the super Brownian motion with underlying dimension numberd 3, completing the results of Iscoe (1986).  相似文献   
5.
独居石微晶玻璃中玻璃相含量的红外光谱定量测定   总被引:2,自引:0,他引:2  
独居石微晶玻璃由偏磷酸盐玻璃和独居石两相组成。玻璃和独居石的红外吸收谱带彼此不相重叠,且1275和616cm~(-1)谱带的吸收强度随玻璃相的含量变化而变化。两谱带的对数吸光度比值与玻璃相含量(w%)的相关系数r=0.9975,其回归方程为y=48.356 25.93x。合成独居石的IR谱中952和616cm~(-1)谱带的吸光度比值也随不同的Ce_2O_3/La_2O_3比值规律变化。其r=0.9917,回归方程为y=0.2211exp(0.0221x)。高的相关性表明IR技术可在磷酸盐微晶玻璃物相定量分析中得到实际应用。  相似文献   
6.
Entamoeba histolytica is an intestinal parasite and the causative agent of amoebiasis, which is a significant source of morbidity and mortality in developing countries. Here we present the genome of E. histolytica, which reveals a variety of metabolic adaptations shared with two other amitochondrial protist pathogens: Giardia lamblia and Trichomonas vaginalis. These adaptations include reduction or elimination of most mitochondrial metabolic pathways and the use of oxidative stress enzymes generally associated with anaerobic prokaryotes. Phylogenomic analysis identifies evidence for lateral gene transfer of bacterial genes into the E. histolytica genome, the effects of which centre on expanding aspects of E. histolytica's metabolic repertoire. The presence of these genes and the potential for novel metabolic pathways in E. histolytica may allow for the development of new chemotherapeutic agents. The genome encodes a large number of novel receptor kinases and contains expansions of a variety of gene families, including those associated with virulence. Additional genome features include an abundance of tandemly repeated transfer-RNA-containing arrays, which may have a structural function in the genome. Analysis of the genome provides new insights into the workings and genome evolution of a major human pathogen.  相似文献   
7.
The adsorption of nitric oxide on clean rhenium has been studied by X-ray photoelectron spectroscopy. At room temperature only dissociative adsorption occurs; at 100 K, NO adsorbs molecularly at low coverages. Higher NO exposures lead to the formation of NO2 which dissociates upon warming above 180 K.  相似文献   
8.
The interaction of D2 O with a polycrystalline cerium surface, successfully cleaned by heavy Ar+ bombardment and annealing, was studied at 120 were observed at BE 530.3 (Ce2O3) and 532.7eV (adsorbed OD). When clean Ce at 120 K was exposed to D2 O, the O(1s) spectra were initial eV (adsorbed D2 O). For exposures greater than 10 Langmuir (L), a multilayer of ice grows and the O(1s) spectra become dominated by a peak at 5The results of interaction with D2 O are compared with oxidation by O2. The significant differences are: (1) the absence of Ce(IV) when oxidati relatively small extent of oxidation that occurs when Ce is exposed to D2 O at 120 K, and (3) the larger chemical-shift of the Ce(III)-derived specThe XPS studies of the interaction of D2 O with Ce reported here may be summarized as follows:(1) Exposure at 300 K gives rise to O(1s) features characteristic of oxide and hydroxide, while the Ce(3d) spectra indicate Ce(III), but no CE((2) Exposure at 120 K gives O(1s) features characteristic of adsorbed OD, chemisorbed D2 O, a multilayer of ice, and a small amount of oxide. T are characteristic of clean Ce except for slight broadening.(3) Exposure at 120 K followed by warming to 240 and 300 K gives spectra characteristic of hydroxide and oxide surface-species. Between 240 and 300 K, O(1s) intensity.(4) At 300 K, a relatively thick layer of oxide forms, and after an exposure of 50 L the features characteristic of metallic Ce are no longer observabl(5) As compared to the case for O2, exposure to D2 O gives rise to different satellite-splittings in the Ce(3d) spectra, suggesting that di formed in the two cases.(6) The spectra observed for Ce exposed to D2 O are in excellent accord with those found for the heavier lanthanides [4].  相似文献   
9.
In order to verify that the protocols used for water quality monitoring of surface waters within the Long-term Environmental Research Monitoring and Testing System (OPE), located in the north-eastern part of France in relation with a geological disposal for radioactive waste project, are fit for purpose, a validation study was conducted following the methodology described in the Eurachem/citac and Nordtest guidance documents on uncertainty arising from sampling. As one of the objectives of the OPE water monitoring programme was to investigate the spatial and temporal variability of water quality, quality requirements were set to having a measurement variance, including sampling and analytical contributions, less than 20 % of the total variance to minimise the impact of measurement over the observed environmental variability. The replicate method was then selected in order to estimate the measurement uncertainty, including the sampling contribution, as well as the spatial and temporal variability of water quality of surface waters. To minimise costs, a single-split level was selected. Analytical uncertainties were assessed from inter-laboratory data and/or internal quality control data from the last 2–5 years. Finally, ANOVA was applied to the data sets after elimination of outliers. Results showed that for pH, electrical conductivity, turbidity and nitrate, the sampling uncertainty was negligible, whereas for other parameters such as dissolved oxygen, total suspend solids, total organic carbon, nitrite and phosphate, the sampling contribution to the measurement uncertainty was largely significant. For all parameters except calcium, the sampling and analytical protocols were considered fit for purpose.  相似文献   
10.
Rigid control of synthesis of collagen types I and III by cells in culture   总被引:8,自引:0,他引:8  
A J Hance  R G Crystal 《Nature》1977,268(5616):152-154
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