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41.
42.
Concentrations and determinants of organochlorine levels among pregnant women in Eastern Spain 总被引:1,自引:0,他引:1
Sabrina Llop Ferran Ballester Esther Vizcaino Maria-Jose Lopez-Espinosa Marisa Rebagliato Alfredo Marco Joan O. Grimalt 《The Science of the total environment》2010,408(23):5758-5767
Persistent organic pollutants (POPs) comprise a large variety of toxic substances with ample distribution. While exposure to these toxins occurs mainly through diet, maternal POP levels may be influenced by certain sociodemographic, environmental, or lifestyle factors. This is important given that these substances may have adverse effects on fetal development. The aim of this study is to examine the sociodemographic, environmental, lifestyle, and dietary determinants of the levels of hexachlorobenzene (HCB), b-hexachlorocyclohexane (b-HCH), 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (4,4′-DDT), 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (4,4′-DDE), and polychlorinated biphenyls (PCB congeners 118, 138, 153, 180) measured in the blood of pregnant women participating in a mother-child cohort study conducted in Valencia (Spain).The study population consisted of 541 pregnant women who formed part of the INMA (Childhood and the Environment) cohort (2004-2006). POP levels were determined in blood taken during the 12th week of pregnancy with the aid of gas chromatography with electron capture detection. Sociodemographic, environmental, and dietary information was obtained from a questionnaire. Multivariate Tobit regression models were constructed in order to assess the association between POP levels and selected covariates.The results showed that all the women had detectable levels of at least one of these compounds while in 43% of the subjects, all eight compounds were detected. The compounds found in the greatest number of women were 4,4′-DDE (100%) and PCBs 153 and 180 (95%). The most important determinants of high POP levels were the mother's age, country of origin, increased body mass index, and number of weeks of breastfeeding after previous pregnancies. With regard to diet, 4,4′-DDT and 4,4′-DDE levels increased with the intake of meat, fruit, and cereal. PCB 153 levels increased with the intake of seafood. The levels of HCB, b-HCH, 4,4′-DDT, and 4,4′-DDE observed in this study were slightly higher than in other studies, whereas the PCB levels were similar. 相似文献
43.
Leščić Ašler I Ivić N Kovačić F Schell S Knorr J Krauss U Wilhelm S Kojić-Prodić B Jaeger KE 《Chembiochem : a European journal of chemical biology》2010,11(15):2158-2167
Several hydrolases of the SGNH superfamily, including the lipase SrLip from Streptomyces rimosus (Q93MW7), the acyl-CoA thioesterase I TesA from Pseudomonas aeruginosa (Q9HZY8) and the two lipolytic enzymes EstA (from P. aeruginosa, O33407) and EstP (from Pseudomonas putida, Q88QS0), were examined for promiscuity. These enzymes were tested against four chemically different classes of a total of 34 substrates known to be hydrolysed by esterases, thioesterases, lipases, phospholipases, Tweenases and proteases. Furthermore, they were also analysed with respect to their amino acid sequences and structural homology, and their phylogenetic relationship was determined. The Pseudomonas esterases EstA and EstP each have an N-terminal domain with catalytic activity together with a C-terminal autotransporter domain, and so the hybrid enzymes EstA(N)-EstP(C) and EstP(N)-EstA(C) were constructed by swapping the corresponding N- and C-terminal domains, and their hydrolytic activities were compared. Interestingly, substrate specificity and kinetic measurements indicated a significant influence of the autotransporter domains on the catalytic activities of these enzymes in solution. TesA, EstA and EstP were shown to function as esterases with different affinities and catalytic efficacies towards p-nitrophenyl butyrate. Of all the enzymes tested, only SrLip revealed lipase, phospholipase, esterase, thioesterase and Tweenase activities. 相似文献
44.
Simple sample preparation procedures involving sonication and solid phase extraction (SPE), followed by reversed-phase high performance liquid chromatography (HPLC) and spectrofluorometric detection, were used to analyse polycyclic aromatic hydrocarbons (PAHs) in soil and olives collected in areas contaminated with creosote-treated railway ties. Very high PAH contents (with amounts ranging from 114.7 to 2157.2 and from 167.3 to 3121.8 microg kg(-1) dry weight for total light PAHs and total heavy PAHs, respectively) were found in soil sampled up to 1 m from the source of contamination. The PAH load decreased rapidly with the distance from the railway ties. High amounts of light PAHs, up to 6359.9 microg kg(-1), were also found in oil extracted from olives collected in a rural area where old railway ties were stored. No appreciable transfer of heavy PAHs and benzo[a]pyrene was observed in oil samples. 相似文献
45.
Jun.-Prof. Dr. Sabrina Hedrich Mareike Fritze Prof. Dr. Axel Schippers 《化学,工程师,技术》2023,95(12):1897-1908
Biohydrometallurgy as a section of hydrometallurgy uses specific metabolic capabilities of microorganisms for metal extraction. Biomining is the application of bioleaching for metal extraction from sulfide ores. For recycling, i.e., metal extraction from waste and industrial residues, there are no biohydrometallurgical technologies yet, but promising laboratory studies on metal extraction from solids. In this review article, these are summarized, and perspectives are shown. 相似文献
46.
Sabrina Sicolo Maurizio Bruschi Luca Bertini Giuseppe Zampella Giulia Filippi Federica Arrigoni Luca De Gioia Claudio Greco 《International Journal of Hydrogen Energy》2014
[FeFe]-hydrogenases are the most efficient biological catalysts available for the H2 evolution reaction. Their active site – the H-cluster – features a diiron subsite which has the peculiar characteristic of bearing cyanide groups hydrogen-bonded to the apoprotein as well as carbonyl ligands. Notably, one of the CO ligands is disposed in bridging position between the metal centers. This allows one of the Fe ions to retain a square pyramidal coordination – which determines the assumption of the so-called “rotated structure” – with a vacant coordination site in trans to the μ-CO group, ready to bind protons when the active site is in the FeIFeI state. Many FeIFeI biomimetic models have been synthesized and characterized so far, but most of them fail to reproduce the orientation of the diatomic ligands that is observed in the enzyme active site. 相似文献
47.
Caroline Scholtes Sabrina Nizet Sonia Collin 《Journal of the Institute of Brewing》2012,118(2):223-229
The typical Belgian Gueuze beers are produced with aged hop from a grist of malt and wheat, according to a very long oxidation process (extended boiling, cooling overnight in an open‐air container, oak‐barrel ageing). Two theaspirane‐oxidation‐derived products, dihydrodehydro‐β‐ionone and 4‐hydroxy‐7,8‐dihydro‐β‐ionone, are evidenced here for the first time in Gueuze beers. Both compounds have been recently identified in oxidative wines such as Jura Flor‐Sherry and Sauternes wines. Another analogy with Jura Flor‐Sherry wines was the presence of the nutty/curry odorants sotolon and abhexon, although at lower concentrations. Copyright © 2012 The Institute of Brewing & Distilling 相似文献
48.
49.
Life tasks serve as an avenue for individuals to give personal meaning to their lives and to organize personal effort and activities. The present data, from a longitudinal study of the transition to college life, demonstrate how construals of life tasks can help to illuminate individuals' activity choices and affective experience of daily life activities. Ss who were absorbed in the task of "being on my own, away from family," also invested their academic activities with special significance. They experienced more stress and less satisfaction from their (considerable) academic accomplishments than did those who framed their tasks in more concrete terms. Experience-sampling data showed that activity choices followed from life task concerns, even when such activities were particularly anxiety-provoking. Discussion considers how similar life task themes may be enacted differently in other contexts. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
Bruno Apolloni Simone Bassis Alberto Clivio Sabrina Gaito Dario Malchiodi 《Natural computing》2007,6(1):33-53
We propose an aging mechanism which develops in artificial bacterial populations fighting against antibiotic molecules. The
mechanism is based on very elementary information gathered by each individual and elementary reactions as well. Though we
do not interpret the aging process in strictly biological terms, it appears compliant with recent studies on the field, and
physically feasible. The root of the aging mechanism is an adaptation strategy based on a thresholding operation that derives
from theoretical results on stochastic monotone games. The methods for implementing it denote their rationale in that they
represent a sophisticated dialect of pi-calculus, a widespread computational paradigm for implementing dynamics of massive
populations with bipolar reactions. As a result we may implement processes that explain some typical patterns of the evolution
of the immunosystems. 相似文献