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61.
The photonic nanoarchitectures responsible for the blue colour of the males of nine polyommatine butterfly species living in the same site were investigated structurally by electron microscopy and spectrally by reflectance spectroscopy. Optical characterization was carried out on 110 exemplars. The structural data extracted by dedicated software and the spectral data extracted by standard software were inputted into an artificial neural network software to test the specificity of the structural and optical characteristics. It was found that both the structural and the spectral data allow species identification with an accuracy better than 90 per cent. The reflectance data were further analysed using a colour representation diagram built in a manner analogous to that of the human Commission Internationale de l''Eclairage diagram, but the additional blue visual pigment of lycaenid butterflies was taken into account. It was found that this butterfly-specific colour representation diagram yielded a much clearer distinction of the position of the investigated species compared with previous calculations using the human colour space. The specific colours of the investigated species were correlated with the 285 flight-period data points extracted from museum collections. The species with somewhat similar colours fly in distinct periods of the year such that the blue colours are well tuned for safe mate/competitor recognition. This allows for the creation of an effective pre-zygotic isolation mechanism for closely related synchronic and syntopic species.  相似文献   
62.
The first three-dimensional structure of a type IIa bacteriocin from lactic acid bacteria is reported. Complete 1H resonance assignments of leucocin A, a 37 amino acid antimicrobial peptide isolated from the lactic acid bacterium Leuconostoc gelidum UAL187, were determined in 90% trifluoroethanol (TFE)-water and in aqueous dodecylphosphocholine (DPC) micelles (1:40 ratio of leucocin A:DPC) using two-dimensional NMR techniques (e.g., DQF-COSY, TOCSY, NOESY). Circular dichroism spectra, NMR chemical shift indices, amide hydrogen exchange rates, and long-range nuclear Overhauser effects indicate that leucocin A adopts a reasonably well defined structure in both TFE and DPC micelle environments but exists as a random coil in water or aqueous DMSO. Distance geometry and simulated annealing calculations were employed to generate structures for leucocin A in both lipophilic media. While some differences were noted between the structures calculated for the two different solvent systems, in both, the region encompassing residues 17-31 assumes an essentially identical amphiphilic alpha-helix conformation. A three-strand antiparallel beta-sheet domain (residues 2-16), anchored by the disulfide bridge, is also observed in both media. In TFE, these two regions have a more defined relationship relative to each other, while, in DPC micelles, the C-terminus is folded back onto the alpha-helix. The implications of these structural features with regard to the antimicrobial mechanism of action and target recognition are discussed.  相似文献   
63.
The photochemical properties and photodynamic activity of three porphyrazines (Pzs) containing annulated diazepine rings, including novel demetalated porphyrazine‐possessing bis(styryl)diazepine moieties were investigated. The porphyrazines were evaluated in terms of their electronic absorption and emission properties, their tendency to undergo aggregation and photodegradation, as well as their singlet oxygen generation efficiency. The in vitro photodynamic activity of the porphyrazines and their liposomal formulations were examined by using two oral squamous cell carcinoma cell lines. Magnesium(II) tribenzodiazepinoporphyrazine ( 1 ) revealed the highest phototoxic effect in both cell lines used, H413 and HSC‐3. Encapsulation of Pz 1 into L ‐α‐phosphatidyl‐d,l ‐glycerol:1‐palmitoyl‐2‐oleoyl‐sn‐glycero‐3‐phosphocholine liposomes resulted in a nearly threefold increase in photocytotoxicity relative to that of the solution of Pz 1 (IC50 values of 45 and 129 nM , respectively).  相似文献   
64.
An evaluation is presented of the experience of patients, families and staff in two infusion suites. One infusion suite was a facility occupied until 2009 and the other suite was the replacement for that facility. The primary design objectives of the new facility were to support social interaction, provide opportunities for privacy and provide visual access to nature. The effectiveness of the new facility relative to the old facility with regard to these three design objectives served as the source of hypotheses for the study. Using a Likert-style survey and open-ended questions, the findings suggest that the new facility was successful at addressing these design goals. Subjects were also queried regarding whether these design objectives were important in an infusion suite. The vast majority of the respondents in the new facility indicated that social interaction, privacy and access nature were important in this setting.

Il est présenté une évaluation de l'expérience vécue par les patients, les familles et les employés dans deux centres de perfusion. L'un des centres de perfusion était un établissement occupé jusqu'en 2009 et l'autre centre était celui qui a remplacé cet établissement. Les principaux objectifs de conception du nouvel établissement étaient de favoriser l'interaction sociale, de fournir des possibilités de vie privée et d'assurer un accès visuel à la nature. L'efficacité du nouvel établissement par rapport à l'ancien du point de vue de ces trois objectifs de conception a servi d'hypothèse pour l'étude. Obtenus en utilisant une enquête basée sur l'échelle de Likert et des questions ouvertes, les résultats suggèrent que le nouvel établissement a réussi à satisfaire à ces objectifs de conception. Il a également été demandé aux sujets de l'étude si ces objectifs de conception avaient de l'importance dans un centre de perfusion. La grande majorité des personnes interrogées dans le nouvel établissement ont indiqué que l'interaction sociale, la vie privée et l'accès à la nature étaient des éléments importants dans ce contexte.

Mots clés: établissement de lutte contre le cancer, évaluation d'établissement, soins de santé, centre de perfusion, occupation, vie privée, interaction sociale  相似文献   
65.
Detection of microbial contamination of packaging for foodstuffs and of the environment, using a gas chromatography–mass spectrometry (GC–MS) method, is described. Quantitative determination of muramic acid, a chemical marker of bacterial peptidoglycan, has been used for this purpose. Samples of dust collected from packaging material (plastic film in the store‐room), intended to come into contact with foodstuffs, and dust from a laboratory environment were hydrolysed in aqueous hydrochloric acid and next extracted with hexane to remove hydrophobic compounds. The aqueous phase was evaporated, heated in silylation reagent to trimethylsilyl derivatives and analysed by GC–MS. Internal standard (3‐hydroxytridecanoic methyl ester) was added before silylation procedure for quantification purposes. The method described is quick and simple, can be applied to study chemical markers directly without prior culturing, in complex environmental samples (not only of packaging), and should therefore become widely used for measuring bacterial peptidoglycan. The method can be used for the detection of microbial infection in humans, hospitals, infusing fluids, contamination of biochemical and fermentation processes, and for monitoring of air, water, air‐conditioning systems, etc. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
66.
Graft copolymers of potato starch with acrylamide, acrylamide, and acrylic acid or N‐vinylformamide in the presence of 1–16 wt % montmorillonite were manufactured via reactive extrusion. XRD and TEM measurements exhibited intercalated structure of clay dispersion (d001 distance up to 2.3 nm). The influence of graft polymer(s) system and montmorillonite content on thermal properties, water sorption as well as polyvalent metal cation (Cd2+ and Fe3+) sorption of obtained starch graft copolymers has been determined. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
67.
The total lipids (8.6%) extracted from whole lupin seeds (Lupinus angustifolius L. var. “Uniwhite”) were found to be comprised of triglycerides (71.1%), phospho-lipids (14.9%), free sterols (5.2%), glycolipids (3.5%), sterol and wax esters (0.5%), free alcohols (0.4%), hydrocarbons (0.4%) and unidentified waxy material (4.0%). The main fatty acids in the total lipid extract were linoleic (48.3%), oleic (31.2%), palmitic (7.6%) and linolenic (5.4%). Erucic acid was not present, nor were cyclopropenoid acids. Seed coatings constituted 23.9% of the weight of the whole seeds and contained 1.5% lipids, the main classes of which were triglycerides (38.4%), free sterols (28.0%), phospholipids (9.7%), glycolipids (9.1%) and free alcohols (3.7%). The seed coatings and kernels contained the same fatty acid constituents, but the proportions of oleic, linoleic and linolenic acids were markedly different. β-Carotene was present, although at low concentration. When evaluated on its lipid composition, “Uniwhite” lupin seed appears suitable as a supplement for pig, poultry and stock feeding.  相似文献   
68.
69.
Laboratory and full-scale experiments were conducted to investigate the development and effect of heterogeneity caused by filter media nonuniformity, biofilm, particles, precipitates, and gas bubbles in rapid sand filters used for drinking-water treatment. Salt tracer experiments were conducted in laboratory columns and in a waterworks, where a new tracer method for rapid sand filters was developed. Pore-water velocities and dispersivities were estimated by fitting an analytical solution to the measured breakthrough curves. Results of the column experiments showed an increase in average longitudinal dispersivity of more than 33% in the 116?h after the start of filtration with a constant pore-water velocity and a zero-order nitrification rate of 9??mg?N/L/h. The full-scale experiments showed that the rapid sand filter was heterogeneous with pore-water velocities ranging from 2.2 to 3.3??m/h for the same inlet flow. A first-order nitrification reaction with spatially variable pore-water velocity could be interpreted as a zero-order reaction with a constant pore-water velocity. A model demonstrated that filter heterogeneity could result in higher filter outlet ammonium concentrations.  相似文献   
70.
The present work determined iron content in fourteen species of vegetable prepared for consumption. The experimental material consisted of raw and boiled raw vegetables and two types of frozen product: one traditionally produced (blanching before freezing); the other obtained using the modified method (boiling before freezing), having the characteristics of a ready‐to‐eat convenience product. Nutrient density (ND) and recommended dietary intake (RDI) were established on the basis of iron content. The highest iron content was found in pea seeds (2.03 mg per 100 g fresh weight) and the lowest in root vegetables (0.38–0.60 mg). Iron retention was similar in all pea, broad bean, New Zealand spinach, kale, white cauliflower, celery and red beet products. In the remaining products, the significantly lowest retention was found in the traditionally frozen product (Sample C) and the highest in the ‘convenience’ frozen product (Sample D). The above‐mentioned order also applied to ND and RDI values. Only in the ND of parsnip calculated for women did any value fall below 100%.  相似文献   
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