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131.
Gabriella Di Lena Irene Casini Roberto Caproni Elena Orban 《Food Additives and Contaminants: Part B: Surveillance Communications》2018,11(3):175-182
This study investigated mercury contamination levels in eight commercially valuable crustacean species caught off the Central Adriatic and Tyrrhenian coasts of Italy. Total mercury levels were measured by Thermal Decomposition-Amalgamation-Atomic Absorption Spectrophotometry. Results showed a high variability among species with values ranging from 0.070 to 1.24 (mg kg?1 wet weight). The lowest mercury levels were detected in caramote prawn (Penaeus kerathurus), warty crab (Eriphia verrucosa) and European spider crab (Maja squinado), decapods living in shallow waters. Levels exceeding the limits established by the European Commission were found in species living in close contact with bottom sediments: deepwater rose shrimp (Parapenaeus longirostris), blue and red shrimp (Aristeus antennatus) and Norway lobster (Nephrops norvegicus). For shrimps, the inter-individual variability observed was mostly related to the body size, indicating the accumulation of mercury with age. An estimation of the human intake of mercury associated to the consumption of the crustaceans sampled and its comparison with the Tolerable Weekly Intake are provided. 相似文献
132.
Chemical characterization of 21 species of marine macroalgae common in Norwegian waters: benefits of and limitations to their potential use in food and feed 下载免费PDF全文
Irene Biancarosa Ikram Belghit Christian G Bruckner Nina S Liland Rune Waagbø Heidi Amlund Erik‐Jan Lock 《Journal of the science of food and agriculture》2018,98(5):2035-2042
BACKGROUND
In the past few years, much effort has been invested into developing a new blue economy based on harvesting, cultivating and processing marine macroalgae in Norway. Macroalgae have high potential for a wide range of applications, e.g. as source of pharmaceuticals, production of biofuels or as food and feed. However, data on the chemical composition of macroalgae from Norwegian waters are scant. This study was designed to characterize the chemical composition of 21 algal species. Both macro‐ and micronutrients were analysed. Concentrations of heavy metals and the metalloid arsenic in the algae were also quantified.RESULTS
The results confirm that marine macroalgae contain nutrients which are relevant for both human and animal nutrition, the concentrations whereof are highly dependent on species. Although heavy metals and arsenic were detected in the algae studied, concentrations were mostly below maximum allowed levels set by food and feed legislation in the EU.CONCLUSION
This study provides chemical data on a wide range of algal species covering the three taxonomic groups (brown, red and green algae) and discusses both benefits of and potential limitations to their use for food and feed purposes. © 2017 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献133.
Irene Pagana Ruben Morawicki Tiffany J. Hager 《International Journal of Food Science & Technology》2014,49(2):641-649
Organic waste generated from industrial sweet potato canning is estimated to be 30% of incoming raw material with significant residual carbohydrate content. The purpose of this study was to evaluate the potential of waste generated from sweet potato processing material to support the growth of lactic acid bacteria and the production of lactic acid. The waste was comprised of 16.5% solids consisting of 18.5% ash, 4.4% protein, 20.5% simple sugars and 19% soluble starch. Following a screening of three lactic acid bacteria strains, Lactobacillus rhamnosus was deemed the best candidate for lactic acid production. The potential of various dilutions of the enzyme‐hydrolysed waste, with and without pH control, as a fermentation substrate was evaluated. Lactic acid production was highest in hydrolysed waste (without dilution) at pH set point 5.0, yielding 10 g L?1 in 72 h. Thus, lactic acid, a valuable organic compound, can be generated from sweet potato waste. 相似文献
134.
Antonio Raffo Irene Baiamonte Nicoletta Nardo Flavio Paoletti 《European Food Research and Technology》2007,225(3-4):395-405
Physical (weight, firmness) and compositional (sugars, organic acids, ascorbic acid, phenolic compounds and carotenoids) changes
of red sweet peppers (Capsicum annuum L.) were monitored during 21 days of cold storage (at 7.5 °C); fruits were stored without packaging, packaged in low density
polyethylene bags, or after hot water dipping (53 °C for 4 min) and packaging. Packaging prevented water loss, and preserved
the firmness of the fresh product. Sugars (fructose and glucose) content was practically constant throughout the whole storage
time, for all treatments. A moderate accumulation of citric acid was observed during storage, but no marked effects of packaging
and hot water dipping on citric and malic acid content. Ascorbic acid content slightly increased in unpackaged and packaged
fruits, but not in treated+packaged peppers. Hydroxycinnamics total content seemed not to be affected by cold storage, packaging
or hot water treatment, whereas glycosylated flavonoids showed somewhat lowered levels during storage, particularly in the
case of unpackaged and packaged+treated fruits. Regarding carotenoids content, the effect of the considered storage conditions
seemed to be much smaller than that due to ripening stage. Provitamin A content showed an increasing trend in unpackaged and
packaged fruits; packaged+treated peppers were characterised by a lower retention of provitamin A and a higher level of capsanthin
and cucurbitaxanthin A with respect to not treated fruits. On the whole, packaging and hot water treatment did not produce
noticeable adverse effects on the majority of the examined compositional quality parameters. 相似文献
135.
Irene Muñoz-González Fernando Sánchez-Patán Ana Jiménez-Girón Carolina Cueva María Monagas Pedro J. Martín-Álvarez M. Victoria Moreno-Arribas Begoña Bartolomé 《Food Analytical Methods》2014,7(4):844-853
Solid phase extraction (SPE) methodology has been evaluated as a cleanup strategy prior to the analysis of phenolic metabolites in fecal samples by UPLC–DAD–ESI–TQ MS. Among the sorbents tested, Oasis® HLB led to the higher phenolic standard recoveries. Sample acidification (0.4 M HCl, final concentration) before SPE considerably improved standard recoveries. Values of the process efficiency (CSPE/CWithout SPE) for a standard solution containing gallic acid, protocatechuic acid, caffeic acid, benzoic acid, 3-phenylpropionic acid, (+)-catechin, (?)-epicatechin, procyanidin B2, and 4-hydroxybenzoic 2,3,5,6 d4 acid were acceptable (>90 %) for all compounds, except for procyanidin B2 (26 %). The developed SPE methodology was applied to fecal samples of individuals subjected to a wine intervention study. Phenolic metabolites, including intermediate metabolites (phenyl-γ-valerolactones and phenylvaleric acid derivatives) and end products (simple phenols, hydroxyphenylpropionic, hydroxyphenylacetic, hydroxycinnamic, and hydroxybenzoic acids) were identified. Most of the compounds (n?=?14) exhibited values of process efficiency between 85 and 115 %. Although some compounds (n?=?4) showed process efficiency>115 %, there was a group of metabolites (4-O-methylgallic acid, syringic acid, and 4-hydroxy-5-(3′,4′-dihydroxyphenyl)-valeric acid) whose process efficiency was <85 %, which represented a serious limitation and made us to discard SPE as a preparative technique for the analysis of these phenolic metabolites. Finally, the paper reports the concentrations of phenolic metabolites in a randomized set of human fecal samples from healthy volunteers (n?=?15) without any previous SPE application. Large inter-individual variability was observed, which was attributed to differences in human gut microbiota composition. 相似文献
136.
Moderate consumption of red wine provides beneficial effects to health. This is attributed to polyphenol compounds present in wine such as resveratrol, quercetin, gallic acid, rutin, and vanillic acid. The amount of these antioxidants is variable; nevertheless, the main beneficial effects of red wine are attributed to resveratrol. However, it has been found that resveratrol and quercetin are able to photosensitize singlet oxygen generation and conversely, gallic acid acts as quencher. Therefore, and since resveratrol and quercetin are some of the most important antioxidants reported in red wines, the aim of this research was to evaluate the photosensitizing ability of 12 red wine extracts through photo‐oxidation of ergosterol. The presence of 1O2 was detected by ergosterol conversion into peroxide of ergosterol through 1H NMR analysis. Our results showed that 10 wine extracts were able to act as photosensitizers in the generation of singlet oxygen. The presence of 1O2 can damage other compounds of red wine and cause possible organoleptic alterations. Finally, although the reaction conditions employed in this research do not resemble the inherent conditions in wine making processing or storing, or even during its consumption, this knowledge could be useful to prevent possible pro‐oxidant effects and avoid detrimental effects in red wines. 相似文献
137.
José?Luis?Pe?alvoEmail author M.?Con?eic?o?Castilho M.?Irene?N.?Silveira M.?Cruz?Matallana M.?Esperanza?Torija 《European Food Research and Technology》2004,219(3):251-253
Soymilk is a water extract of soybeans, closely resembling dairy milk in physical appearance and composition. Most fatty acids in soybean and its derivates are unsaturated, and therefore susceptible to oxidation. The aim of this study was to evaluate the possible effect of the thermal conditions during the elaboration process of soymilk on its fatty acid profile. For this, the fatty acid composition of soymilk, okara (soymilk residue), and soybean were studied by gas chromatography with flame ionization detection (GC-FID). No major differences in the fatty acid patterns were found. 相似文献
138.
Muimba A Kankolongo Kerstin Hell Irene N Nawa 《Journal of the science of food and agriculture》2009,89(8):1366-1375
BACKGROUND: Maize constitutes the main staple food and most important crop grown in Zambia. However, maize incurs considerable losses both in field and storage due to pathogens and insects. Some of the pathogens and resultant mycotoxins reduce the nutritional quality of the product. Mycotoxins are toxigenic fungal compounds that can cause cancer and suppress growth. In spite of this health hazard, there has been very little research to document their occurrence. Maize grains stored for human consumption were sampled from different agro‐ecosystems (forest, valley and plateau areas) of three agroecological zones (high, mid and low altitude). RESULTS: Several fungal genera were recovered among which Aspergillus flavus, A. niger, Fusarium verticillioides, F. solani, Rhizopus stolonifer and Penicillium spp. were prevalent. The weevil Sitophilus zeamais and the larger grain borer Prostephanus truncatus were the most damaging. Enzyme‐linked immunosorbent assay (ELISA) tests yielded fumonisins and aflatoxins ranging between 0.02 and 21.44 ppm, and 0.7 and 108.39 ppb in 96.4% and 21.4% of samples, respectively. Fumonisin was more pronounced in villages in forest areas whereas aflatoxin was highest in valley and forest areas in Zone II. CONCLUSION: Strategic interventions to curtail fungal, mycotoxin and insect contamination should be directed towards improved agronomic and post‐harvest practices of maize from fields to consumers. Copyright © 2009 Society of Chemical Industry 相似文献
139.
140.
Irene R. Grant Antonio C.G. Foddai James C. Tarrant Brenna Kunkel Faye A. Hartmann Sheila McGuirk Chungyi Hansen Adel M. Talaat Michael T. Collins 《Journal of dairy science》2017,100(12):9723-9735
When advising farmers on how to control Johne's disease in an infected herd, one of the main recommendations is to avoid feeding waste milk to calves and instead feed calf milk replacer (CMR). This advice is based on the assumption that CMR is free of viable Mycobacterium avium ssp. paratuberculosis (MAP) cells, an assumption that has not previously been challenged. We tested commercial CMR products (n = 83) obtained from dairy farms around the United States by the peptide-mediated magnetic separation (PMS)-phage assay, PMS followed by liquid culture (PMS-culture), and direct IS900 quantitative PCR (qPCR). Conventional microbiological analyses for total mesophilic bacterial counts, coliforms, Salmonella, coagulase-negative staphylococci, streptococci, nonhemolytic Corynebacterium spp., and Bacillus spp. were also performed to assess the overall microbiological quality of the CMR. Twenty-six (31.3%) of the 83 CMR samples showed evidence of the presence of MAP. Seventeen (20.5%) tested positive for viable MAP by the PMS-phage assay, with plaque counts ranging from 6 to 1,212 pfu/50 mL of reconstituted CMR (average 248.5 pfu/50 mL). Twelve (14.5%) CMR samples tested positive for viable MAP by PMS-culture; isolates from all 12 of these samples were subsequently confirmed by whole-genome sequencing to be different cattle strains of MAP. Seven (8.4%) CMR samples tested positive for MAP DNA by IS900 qPCR. Four CMR samples tested positive by both PMS-based tests and 5 CMR samples tested positive by IS900 qPCR plus one or other of the PMS-based tests, but only one CMR sample tested positive by all 3 MAP detection tests applied. All conventional microbiology results were within current standards for whole milk powders. A significant association existed between higher total bacterial counts and presence of viable MAP indicated by either of the PMS-based assays. This represents the first published report of the isolation of viable MAP from CMR. Our findings raise concerns about the potential ability of MAP to survive manufacture of dried milk-based products. 相似文献