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991.
Raquel Ibáñez Marco Peluso Armelle Munnia Sara Piro Carlos A. González Pilar Amiano M. J. Tormo Eva Ardanaz Aurelio Barricarte Antonio Berenguer M. Dolores Chirlaque Miren Dorronsoro Paula Jakszyn Nerea Larrañaga Carmen Martínez Carmen Navarro J. Ramón Quirós M. José Sánchez Antonio Agudo 《European Food Research and Technology》2009,229(4):549-559
The aim of this study was to assess the relationship between bulky DNA adducts in white blood cells (WBC) and lifestyle factors
in a sample from the Spanish cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC). 296 subjects
aged between 35 and 64 years, from five regions, were included. Food intake was estimated with a computerized version of dietary
history questionnaire. Daily intake of polycyclic aromatic hydrocarbons (PAH) was estimated using a database with information
on food content of potential carcinogens. Data on lifestyle and health factors were collected and DNA adducts measured using
the nuclease P1 32P-postlabelling technique. Geometric means of adducts were similar for men and women (4.11/109 and 3.94/109 nucleotides, respectively). Highest levels of adduct were observed in non-smokers and non-occupationally exposed. Meat intake,
oils and fats were associated with higher levels of adducts, but all non-statistically significant. Higher intakes of calcium,
sodium and phosphorus were associated with lower adducts levels. Summarising, our study shows that bulky adducts measured
by 32P-postlabelling in DNA from WBC do not correlate with the usual diet of healthy Spanish adults. Although it has been proposed
that diet be the main source of PAH in nonsmokers without occupational exposure, DNA adducts do not seem to be suitable biomarkers
of dietary PAH in general population. 相似文献
992.
Guillermo Niño-Medina Elizabeth Carvajal-Millán Jaime Lizardi Agustín Rascon-Chu Jorge A. Marquez-Escalante Alfonso Gardea Ana L. Martinez-Lopez Victor Guerrero 《Food chemistry》2009
Water-soluble feruloylated arabinoxylans were extracted from maize processing waste water (nejayote) generated from tortilla-making industries. Nejayote arabinoxylans (NAX) presented a ferulic acid content of 0.23 μg/mg, an arabinose to xylose ratio (A/X) of 0.65, an intrinsic viscosity, [η], of 183 ml/g and a molecular weight (Mw) of 60 kDa. Laccase-induced gels were obtained from 4% (w/v) NAX solution while, at lower concentrations, no gelation was observed. Laccase covalent cross-linking of NAX led to the formation of diferulic (di-FA) and triferulic (tri-FA) acid structures. 4% (w/v) NAX gel presented di-FA and tri-FA contents of 0.02 and 0.01 μg/mg NAX, respectively, and a G′ value of 2 Pa. Recuperation of this gum from a low-value maize by-product could represent a commercial advantage over other gums commonly used in the food industry. 相似文献
993.
Antonio Bevilacqua Marianne Perricone Marianna Cannarsi Maria Rosaria Corbo & Milena Sinigaglia 《International Journal of Food Science & Technology》2009,44(11):2198-2207
This study focused to investigate the technological significance and the spoiling impact of diverse yeast strains, isolated from 'Bella di Cerignola' Italian table olives. Sixty-four isolates (belonging mainly to the species Candida famata and C. guilliermondii ) were studied to assess their growth at different temperatures (15, 25 and 37 °C), pHs (4.0, 5.0 and 9.5) and NaCl concentrations (0–10.0%) in lab medium. Their pectolytic, xylanolytic, lipolytic and catalase activities were also evaluated. Most of the yeasts showed a moderate pectolytic activity and were able to grow at pH 9.5 after 120 h of incubation. Salt and temperature were the most important environmental variables affecting yeast growth, which could exert a strong selective pressure on yeast population. Candida guilliermondii appeared more resistant to high salt concentrations, whereas C. famata was able to grow at 15 °C. 相似文献
994.
Antonio Ferrante Livia Martinetti & Tommaso Maggiore 《International Journal of Food Science & Technology》2009,44(5):1050-1056
Consumers are oriented towards fresh-cut vegetables that provide phytonutrients useful for preventing stress-related diseases. The aim of this work was to evaluate the cut operations on the quality changes of lamb's lettuce ( Valerianella olitoria L.) cv. Trofy during storage at 4 °C for 8 days. Results showed that chlorophyll and carotenoids reduction was observed after 8 days of storage. In both treatments, total carotenoids after 8 days decreased from 20 to 16 mg g−1 FW. Free and total phenols increased with storage in both treatments. Total phenols were 23% higher in control (32 μmol g−1 FW) compared to cut leaves (25 μmol g−1 FW) after 8 days of storage. Anthocyanins increased after 8 days and reached 30 mg 100 g−1 FW without significant difference between treatments. Ascorbic acid (AsA) and dehydroascorbic (DHA) acid increased in cut leaves compared to control. After 1 day AsA concentration was 3 300 nmol g−1 FW in cut leaves, while in control leaves was 1 500 nmol g−1 FW. Analogously AsA + DHA was higher in cut leaves, 4 100 nmol g−1 FW, while in control leaves the mean was 3 000 nmol g−1 FW. After 5 days of storage the values of AsA returned to initial values, while AsA + DHA were lower. 相似文献
995.
Antonio Bevilacqua Milena Sinigaglia & Maria Rosaria Corbo 《International Journal of Food Science & Technology》2009,44(2):380-385
A three variables–five levels central composite design was used to study the effects of pH (3.5, 4.0, 4.5, 5.0 and 5.5), cinnamaldehyde (0, 40, 80, 120 and 160 ppm) and heating temperature (80, 84, 88, 92 and 96 °C) on the spores of Alicyclobacillus acidoterrestris in malt extract broth (MEB). The heat shock resulted in a slight decrease of spore number from 3.2 to 2.5 log CFU mL−1 and occurred at 80–85 °C depending on the pH of the medium. Otherwise, cinnamaldehyde acted as an additional hurdle within the storage time; the critical amounts to be used were included in the range 41.35–44.42 ppm of cinnamaldehyde and were related positively to the pH, i.e. the critical amount of active compound decreased with the decreasing of the pH. 相似文献
996.
Web mining based on Growing Hierarchical Self-Organizing Maps: Analysis of a real citizen web portal 总被引:1,自引:0,他引:1
Antonio Soriano-Asensi Jos D. Martín-Guerrero Emilio Soria-Olivas Alberto Palomares Rafael Magdalena-Benedito Antonio J. Serrano-Lpez 《Expert systems with applications》2008,34(4):2988-2994
This work is focused on the usage analysis of a citizen web portal, Infoville XXI (http://www.infoville.es) by means of Self-Organizing Maps (SOM). In this paper, a variant of the classical SOM has been used, the so-called Growing Hierarchical SOM (GHSOM). The GHSOM is able to find an optimal architecture of the SOM in a few iterations. There are also other variants which allow to find an optimal architecture, but they tend to need a long time for training, especially in the case of complex data sets. Another relevant contribution of the paper is the new visualization of the patterns in the hierarchical structure. Results show that GHSOM is a powerful and versatile tool to extract relevant and straightforward knowledge from the vast amount of information involved in a real citizen web portal. 相似文献
997.
Jesús Agudelo José Antonio Suárez Agustín Olano María Jesús Callejo María Beatriz Colomo 《European Food Research and Technology》1994,199(1):26-28
Gas chromatography was used to study the polysaccharides present in samples that exhibited significant microbially induced viscosity values. Alterations in the media considered were related to the percentage glucose content and the total polysaccharide content. 相似文献
998.
A characterization of minimal complete sets of words of a free monoid which are codes, is given. 相似文献
999.
In der vorliegenden Arbeit wird über Wärmebehandlungen zur Lösung von Chromcarbiden als Vorbeugungsmaßnahme zur Verhinderung der interkristallinen Korrosion berichtet. Vor dem Hintergrund einer möglichen Energieeinsparung wurde ein Temperaturbereich gewählt, der knapp unter dem der industriellen Praxis von 1050°C liegt. Gleichzeitig werden die elektrochemischen Untersuchungsmethoden der Anfälligkeit für interkristalline Korrosion den genormten Methoden gegenübergestellt, um die Anwendungsmöglichkeiten und ihre Verläßlichkeit zu bewerten und einzustufen. Die Ergebnisse zeigen, daß dem Kornzerfall durch Wärmebehandlungen bei 950°C entgegengewirkt werden kann. In vielen Fällen wird diese Temperatur, die rund 100°C unter der in der Industrie angewandten liegt, eine bedeutende Energieeinsparung beinhalten. Allerdings ist diese niedrige Lösungsglühtemperatur nur für molybdänfreie Stähle anzuwenden; für molybdänhaltige, nichtrostende Stähle ist bei Gehalten über rd. 2,5 % Mo eine höhere Lösungsglühtemperatur nach wie vor erforderlich. Das elektrochemische E.P.R.-Verfahren ist eng mit den Versuchen A, C und E der Norm ASTM-A-262 verknüpft. Diese Tatsache wie auch die Einfachheit, Schnelligkeit und der zerstörungsfreie Charakter führen die Autoren zu der Überzeugung, daß die elektrochemische Methode ein idealer Test zur Ermittlung der Anfälligkeit für interkristalline Korrosion ist. 相似文献
1000.
Claudio de A. Loural Romulo A. Zanco Filho Antonio Carlos G. Bordeaux Rego Rogrio C. de Oliveira 《Telematics and Informatics》2006,23(4):294-315
Brazilian telecommunications sector has undergone important modifications in the last 40 years. From a badly structured system of municipal level operators in 1960, with barely one million fixed lines to a large, nation-wide system with about 50 million fixed plus another 75 million mobile lines in 2005. This work paper reviews the institutional framework of telecommunications industrial and technological policy in Brazil in the last four decades, its results and present situation. Infrastructure and services modernisation and expansion process that happened in early 1970s were carried out at the expense of massive import of products and technology. A government strategy was, then, devised to stimulate local industrial and technological development in telecommunications, under the general guidelines of import substitution policy. Essential to this strategy was the creation of an innovation system around TELEBRÁS Research and Development Centre. This technological development model was successful while a protectionist economic policy existed. When economic and political circumstances could not anymore sustain an import substitution approach, in the 1990-decade, the model fell apart and has not been replaced by any other sectorial policy. A critical assessment is carried out, analysing the adopted actions in face of the digital technology maturing process that occurred in meantime. 相似文献