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1.
From November 1992 to February 1993, 455 red deer (Cervus elaphus) were surveyed in order to estimate the prevalence of warble fly (Hypoderma actaeon) larvae under the skin of this ungulate species. Material came from Montes de Toledo, Sierra Morena, Sierra de Alcaraz, and Sierras de Cazorla, Segura y Las Villas Natural Park (central and southern Spain). We observed a prevalence of 92%, with a mean +/- SD intensity of 35.7 +/- 41.3 grubs per parasitized host; there was a maximum of 317 larvae per host. No significant differences in prevalence by host sex were found, although significant differences were observed in prevalences among different host age classes. The main location of feeding larvae in deer was in the back tissues. 相似文献
2.
o-xylene hydrogenation on supported ruthenium catalysts 总被引:1,自引:0,他引:1
P. Reyes M.E. König G. Pecchi I. Concha M. López Granados J.L.G. Fierro 《Catalysis Letters》1997,46(1-2):71-75
The influence of the support on the surface properties and catalytic activity of finely divided ruthenium catalysts is reported.
The catalysts were prepared using an organometallic precursor, Ru(acac)2, and three different supports, Al2O3, TiO2 and SiO2. In order to study the influence of the particle size on the catalytic performance, the effect of the calcination temperature
was also evaluated. XPS suggests that the state of ruthenium is essentially Ru0, and chemisorption measurements indicate a decrease in metal dispersion from catalysts supported on Al2O3 > TiO2 > SiO2. The turnover number in the o-xylene hydrogenation showed significant differences depending on the support and on the particle
size. Additionally, an increase in the selectivity to cis-dimethylcyclohexane with particle size was observed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
3.
Granados M. López Galisteo F. Cabello Lambrou P. S. Alifanti M. Mariscal R. Gurbani A. Sanz J. Sobrados I. Efstathiou A. M. Fierro J. L. G. 《Topics in Catalysis》2007,42(1-4):443-447
The chemical nature of P-containing species of varying concentration present in CeO2 after impregnation with (NH4)2HPO4 and calcination at 1273 K, and their effects on the oxygen storage and release (OSR) properties of ceria are reported for
the first time. The samples were characterized by different techniques and the results were compared with those recently reported
on the same samples but calcined at 873 K. When P-containing ceria solids were calcined at 1273 K, CePO4 (monazite) was the predominant P-containing species on the surface of ceria, confirming previous studies that showed that
monazite exists for those samples in which the surface P loading (P atoms per nm−2) is larger than 5.5. For lower surface P concentrations, isolated orthophosphate units are present at the surface and within
the subsurface region of the solid. Severe sintering of CeO2 after calcination at 1273 K resulted in P concentrations >5.5 P atoms·nm−2 in all samples. Isolated PO4 units that could initially be present in the samples calcined at 873 K nucleated and CePO4 was formed when samples were calcined at 1273 K. OSR properties of CeO2 deteriorated progressively when P loading increased due to the presence of larger crystals of the very stable Ce(III) phase
of CePO4 at the surface of the P-containing ceria solids. 相似文献
4.
JA Tapia Granados 《Canadian Metallurgical Quarterly》1998,3(3):137-151
During the last few decades, traffic injuries have become one of the leading causes of death and disability in the world. In urban areas, traffic congestion, noise, and emissions from motor vehicles produce subjective disturbances and detectable pathological effects. More than one billion people are exposed to harmful levels of environmental pollution. Because its combustion engine generates carbon dioxide (CO2), the automobile is one of the chief sources of the gases that are causing the greenhouse effect. The latter has already caused a rise in the average ambient temperature, and over the next decades it will predictable cause significant climatic changes whose consequences, though uncertain, are likely to be harmful and possibly catastrophic. Aside from the greenhouse effect, the relentless growth of parking zones, traffic, and the roadway infrastructure in urban and rural areas is currently one of the leading causes of environmental degradation. Urban development, which is nearly always "planned" around traffic instead of people, leads to a significant deterioration in the quality of life, while it also destroys the social fabric. Unlike the private automobile, public transportation, bicycles, and walking help reduce pollution, congestion, and traffic volume, as well as the morbidity and mortality resulting from injuries and ailments related to pollution. Non-automobile transportation also encourages physical activity--with its positive effect on general health--and helps reduce the greenhouse effect. The drop in traffic volume and the increased use of alternate means of transportation are thus an integrated health promotion policy which should become an inherent part of the movement for the promotion of healthy cities and of transportation policies and economic policy in general. 相似文献
5.
Greene Paul G.; Zeichner Amos; Roberts Nicolene L.; Callahan Edward J.; Granados Juan L. 《Canadian Metallurgical Quarterly》1989,57(4):484
We evaluated the effects of sensory information about cesarean delivery on prenatal maternal anxiety and on recovery subsequent to delivery by cesarean section. The 42 participants were recruited from a population of obstetric patients. Patients were assigned to either treatment or control groups and identified as sensitizers or repressors. Treatment groups viewed a slide/tape program presenting procedures involved in cesarean delivery. Control groups viewed a program presenting neutral information. Prepared patients classified as sensitizers showed less physiologic arousal during surgery and enhanced postsurgical recovery. Physiologic and self-report measures of anxiety indicated that the intervention itself was not a stressful event. The relations among arousal, subjective anxiety, coping styles, and treatment outcome are discussed and recommendations are made for further investigation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Mzoughi O Gaston F Granados GC Lakhdar-Ghazal F Giralt E Bahraoui E 《ChemMedChem》2010,5(11):1907-1918
The objective of this project was to study the interaction between HR1 and HR2, the stability of the complex formed, and to characterize the antibodies produced against monomeric HR1 and HR2 peptides as well as the HR1-HR2 complex. In this work, HR1 was mimicked by peptide N36, and HR2 was mimicked by peptide C34L and its analogues C34M2, C34M3, and C34D. Whereas C34M2 and C34M3 are partially composed of D-amino acids, C34D has same sequence as C34L, but is assembled entirely of D-amino acids. Using CD analysis, SPR assays, and gel filtration chromatography, we demonstrate the physical interaction between N36 and C34L and its analogues C34M2 and C34M3, but not C34D. We show that the HR1-HR2 complex is formed rapidly (<1?min) and remains stable, as demonstrated by its inability, in contrast to each free peptide, to inhibit the formation of syncytia. To generate antibodies with predetermined specificity against the transiently exposed intermediate that corresponds to the six-helix bundle structure, purified preformed HR1-HR2 complex was used, in parallel with monomeric HR1 and HR2 peptides, as immunogens in mice. Although the produced antibodies recognize total HIV-1 envelope glycoproteins in ELISA, they are unable to neutralize HIV-1-mediated fusion at 37?°C. However, if the incubation with these antibodies is carried out at 27?°C, a temperature that allows stabilization of the transient intermediate complex, anti-peptide antibodies are able to bind their corresponding domains in HeLa cells expressing HIV-1 gp41 in co-culture with HeLa CD4-CCR5/CXCR4 during the dynamic mechanism of membrane fusion. In agreement with the latter results, these antibodies, if previously incubated for 2?h at 27?°C, are able to strongly neutralize HIV-1 entry by membrane fusion, as shown by their ability to block the formation of syncytia. 相似文献
7.
F. Cabello Galisteo C. Larese R. Mariscal M. López Granados J.L.G. Fierro R. Fernández-Ruiz M. Furió 《Topics in Catalysis》2004,(1):451-456
This paper studies oxidation catalytic converters that were vehicle-aged in a diesel automobile. The deposition of several atoms (S, P, C, Si, Ca, Zn and Fe) was detected by several chemical analysis techniques. Moreover, AlPO4 and Al2(SO4)3 were identified by XRD. The catalytic performance of the aged catalysts with different mileages showed a similar degree of deactivation for CO and C3H6 oxidation. By contrast, laboratory sintering carried out on fresh catalysts revealed that it may have certain impact in the deactivation of diesel catalysts. Nevertheless, the possibility that the impact of chemical deposition on deactivation has a threshold value cannot be discarded. 相似文献
8.
I Larizgoitia Jáuregui JR Rodríguez Bermúdez A Granados Navarrete 《Canadian Metallurgical Quarterly》1998,22(8):505-513
The in vivo genotoxic activities in mouse skin of the dimethyl sulphoxide (DMSO) extracts of a range of oil products [residual aromatic extract; untreated heavy paraffinic distillate aromatic extract; mildly refined light naphthenic base oil; bitumen (vacuum residue); high viscosity index base oil obtained by catalytic hydrogenation] were evaluated by 32P-postlabelling DNA analysis. The results of quantitative 32P-postlabelling analyses of epidermal DNA from mice treated with the DMSO extracts showed linear relationships with the total polycyclic aromatic compound (PAC) contents, determined by the Institute of Petroleum method IP 346 and also the 3-6 ring PAC contents, measured by on-line liquid-liquid extraction using flow injection analysis. The 32P-postlabelling data also showed a linear relationship with the mutagenicity indices of these oil products determined in S. typhimurium TA98 using the modified Ames Salmonella microsome test. The in vivo genotoxicity of the DMSO extracts from the oil products was low, judged by 32P-postlabelling analysis of DNA adducts measured in epidermal DNA of treated mouse skin, and ranging from 2 to 723 attomole/microg DNA per mg oil product. The in vivo 32P-postlabelling data from this study are consistent with these materials expressing low genotoxicity in mouse skin in vivo. The DMSO extraction procedure coupled with 32P-postlabelling DNA analysis is useful for ranking the relative genotoxic potency in vivo of a wide range of oil products. In general the trend observed is similar to rankings based on physicochemical measurements of total PAC contents or 3 6 ring PAC contents of the oil products. 相似文献
9.
D. Durán-Martín M. López Granados J. L. G. Fierro C. Pinel R. Mariscal 《Topics in Catalysis》2017,60(15-16):1062-1071
Different CuZn catalysts were prepared by coprecipitation method with Cu/Zn atomic ratio of 0.2, 0.4, 1.0, 2.5 and 6.0. Monometallic Zn and Cu catalysts and a bimetallic catalyst (Cu/Zn?=?2.5) prepared by physical mixture of the precursors were also studied. These catalysts were tested in the glycerol hydrogenolysis reaction and the higher yields to 1,2-propanediol were achieved for Cu/Zn atomic ratio?≥?1 samples. The deactivation of a representative catalyst (Cu/Zn?=?1) was evaluated and its yield to 1,2 propanediol decreases until ca 40% after five runs. To explain this behavior, fresh and used catalysts were characterized by different techniques. Chemical analysis of solid catalysts and liquid reaction medium confirmed the leaching of Zn species under our reaction conditions. This process promotes Cu sintering which is proposed as the actual reason of the observed deactivation in the glycerol hydrogenolysis for this catalytic system. 相似文献
10.
Teodoro Carlón Allende Manuel E. Mendoza Erna Martha López Granados Luis Miguel Morales Manilla 《Water Resources Management》2009,23(12):2587-2603
Efficient natural resources management, including continental water at watershed level, requires understanding the arrangement
of landscape attributes in a region. The geographical analysis of landscape attributes is a useful approach to delineate relatively
homogeneous watersheds or regions. This research was carried out in order to evaluate the effect of land cover through time
on regionalisation modelling in the poorly-gauged Cuitzeo Lake Watershed, and to develop models to create two hydrogeographical
regionalisations for the years 1975 and 2000. The inputs required by the regionalisation methodology were integrated in a
GIS and validated before carrying out statistical regionalisation procedures (cluster analysis and PCA). GIS operations were
done in Arc View 3.2 and statistical analyses in PC-ORD. Median Euclidean distances with mean distance linkage methods were
used. A 75% of similarity was chosen as the threshold to generate regions. Importance rankings of regions were obtained using
multicriteria evaluation methods. Based on the analysis, 38 of the 52 subwatersheds belonging to the Cuitzeo Lake Watershed
were clustered; eight groups were defined in 1975 and nine in 2000. According to PCA, the strongest positive variables are
associated to morphometric, geologic, land cover and soil attributes. Fourteen subwatersheds were never clustered. Four subwatersheds
changed of cluster between 1975 and 2000. This change is explained because of rainfed agricultural parcel abandonment, and
subsequent shrubland growth. This means that the hydrogeographical regionalisation is sensitive to land cover change processes.
The methodological approach applied in this research is a low-cost and fast alternative for evaluating the impact of land
cover and land use change on hydrogeographical regionalisation; in consequence, data and information generated during the
analysis were made available to local authorities so that they can improve both water resources planning and their informational
baseline for decision making and for development of environmental policies in the Cuitzeo Lake Watershed. 相似文献