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91.
Ewa Surwka Dariusz Latowski Micha Dziurka Magdalena Rys Anna Maksymowicz Iwona ur Monika Olchawa-Pajor Christine Desel Monika Krzewska Zbigniew Miszalski 《International journal of molecular sciences》2021,22(21)
To determine the role of α- and γ-tocopherol (TC), this study compared the response to salt stress (200 mM NaCl) in wild type (WT) Arabidopsis thaliana (L.) Heynh. And its two mutants: (1) totally TC-deficient vte1; (2) vte4 accumulating γ-TC instead of α-TC; and (3) tmt transgenic line overaccumulating α-TC. Raman spectra revealed that salt-exposed α-TC accumulating plants were more flexible in regulating chlorophyll, carotenoid and polysaccharide levels than TC deficient mutants, while the plants overaccumulating γ-TC had the lowest levels of these biocompounds. Tocopherol composition and NaCl concentration affected xanthophyll cycle by changing the rate of violaxanthin de-epoxidation and zeaxanthin formation. NaCl treated plants with altered TC composition accumulated less oligosaccharides than WT plants. α-TC deficient plants increased their oligosaccharide levels and reduced maltose amount, while excessive accumulation of α-TC corresponded with enhanced amounts of maltose. Salt-stressed TC-deficient mutants and tmt transgenic line exhibited greater proline levels than WT plants, lower chlorogenic acid levels, and lower activity of catalase and peroxidases. α-TC accumulating plants produced more methylated proline- and glycine- betaines, and showed greater activity of superoxide dismutase than γ-TC deficient plants. Under salt stress, α-TC demonstrated a stronger regulatory effect on carbon- and nitrogen-related metabolites reorganization and modulation of antioxidant patterns than γ-TC. This suggested different links of α- and γ-TCs with various metabolic pathways via various functions and metabolic loops. 相似文献
92.
A hybrid silicon wafer-scale multi-chip packaging design was chosen as the basis for a high performance, high power dissipation
vehicle suitable for VLSI/ULSI applications. The package supports 25 chips (l x l cm), each capable of dissipating as much
as 40 W. The heat generated by the chips is removed by water channels in the underlying structure. Deep- (about 1000 μm),
and shallow- (about 100 μm. deep), channel designs, with a water flow rate of 499 cc/sec, and 39 cc/sec, respectively, have
been analyzed. Both designs are capable of keeping circuit temperature rise small, while maintaining a uniform chip temperature.
The temperature distribution of the thermal module was obtained by solving the 2-D heat conduction equation for isolated heat
sources (the chips), and heat sinks (the water channels). Assuming that each of the 25 chips dissipates 40 W/cm2, and heat is removed only via water flow, the maximum chip tempertaure(t
cc
which occurs at the center of a chip) rise relative to inlet water temperature is 11.4° C, and 19.0° C for the deep, and
shallow designs, respectively. The maximumt
cc
variation between chips on the module (the same as the water temperature rise), for the cases analyzed, is 0.5° C for the
deep-channel design, and 6° C for the shallow-channel design (calculated at 25° C inlet water temperature, and an optimum
flow rate). For the extremely-uneven powered case (all chips except one at the inlet end are powered at 40 W/chip), the maximum
temperature increases between inlet water temperature and chip temperature,t
cc
, remain relatively the same, but the maximumt
cc
variations between chips on the module increase to 11.4° C, and 19° C for the deep, and shallow designs, respectively, as
might be expected. The temperature variation on a powered chip is less than 3° C for both the deep- and shallow-channel designs. 相似文献
93.
Iwona Michalska Andrzej Krysztafkiewicz Mariusz B Bogacki Teofil Jesionowski 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2003,78(4):452-460
The study aimed to obtain highly dispersed particles of zinc silicate, a potential filler of polymers or a paint pigment, by precipitation from solutions of sodium metasilicate and of zinc salts. The technique of silicate precipitation was worked out, and the conditions causing precipitation were optimized. The temperature, sodium metasilicate solution flow rate and concentration of zinc salts were selected so as to obtain silicates of the lowest possible bulk density, and which had low water‐absorbing capacity and high paraffin oil‐absorbing capacity. In the study, the effects of precipitation parameters were examined on the principal physicochemical properties of the silicates, the structure and uniform character of silicate particles, particle size distribution, and the surface morphology. Particular attention was devoted to the particle size distribution and the tendency to form primary agglomerates (aggregates) and secondary agglomerates, using dynamic light scattering (DLS). Studies were undertaken to develop a technique which could prevent formation of silicate particle agglomerates. With this aim, the silicates' surface was modified either during their precipitation or by the so‐called dry technique. For the modification, silane coupling agents were applied. The extent of silicate surface hydrophobicity was examined by estimation of the enthalpies of immersion of the modified silicate surface. The silicates obtained were tested as fillers of rubber mixtures (in butadiene–styrene rubber). © 2003 Society of Chemical Industry 相似文献
94.
This study examined the construct validity of depressive personality disorder (DPD; American Psychiatric Association, 1994). Adult Psychiatric outpatients (N=900) underwent comprehensive Axis I and II evaluations and provided data on 4,768 of their 1st-degree relatives. Despite modest overlap, DPD was not redundant with any Axis I or II disorder. Participants with DPD exhibited more Axis I and Axis II comorbidity, and greater psychosocial dysfunction, than participants without DPD. Relatives of participants with DPD had higher rates of mood disorders, alcohol abuse, and antisocial personality. Results are consistent with findings of several other similar investigations. The authors argue that DPD is a valid construct and should be conceptualized as a personality disorder as opposed to a mood disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
The influence of initial molar ratio of reagents, amount of catalyst, and temperature of reaction between parabanic acid and ethylene carbonate on structure of product was studied. The reaction led to the opening of the trioxoimidazolidine ring, resulting in formation of thermally resistant linear polymeric products constructed of urea and oxoamidoester subunits linked via imide bond. The percentage of side products was estimated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1443–1449, 2006 相似文献
96.
Iwona Konopka ucja Fornal Danuta Abramczyk Jadwiga Rothkaehl & Daniela Rotkiewicz 《International Journal of Food Science & Technology》2004,39(1):11-20
Forty‐two Polish wheat flour were used to establish correlation coefficients between protein content, Zeleny test, falling number value, amylograph viscosity, farinograph water absorption, bread volume and rheological properties of dough, as shown by use of a extrusion chamber and alveograph. The equations expressing the changes of bread volume and flour water absorption as a function of significantly correlated parameters were calculated. The correlations and their significance depended on wheat quality and the alveographic parameters were significantly correlated with the dough extrusion parameters. The dough extrusion parameters were significantly correlated only with the water absorption of soft wheats. The dough rheological tests were correlated to a greater extent with the values of the Zeleny test than to the protein content. The prediction of the bread volume as a function of flour quality parameters and dough rheological properties was best done by grouping wheat varieties into specific qualitative classes. 相似文献
97.
The subject of the work was to study the effect of Si alloying addition to the aluminum on the bond strength properties, wettability,
and structure of interface in the AlSi11/Al2O3 joints. Taking advantage of the sessile drop method, the wetting of alumina substrates by liquid AlSi11 alloy or Al was studied.
The sessile drop tests were carried out in the temperature range between 1023 and 1223 K, under a vacuum of 0.2 mPa for 30
or 120 minutes of contact. The shear strength results demonstrated significant improvement of shear strength of AlSi11/Al2O3 joints due to the application of silicon as an alloying addition to aluminum. Microstructural investigations of interface
indicated that the silicon crystals were formed at the AlSi11/Al2O3 interface, which influenced the strengthening of these joints. A conclusion could be drawn, that the interface structure
influenced the increase of the shear strength of AlSi11/Al2O3 joints. 相似文献
98.
The effect of pulegone chiral center configuration on its antifeedant activity to Myzus persicae was examined. Biological consequences of structural modifications of (R)-(+)- and (S)-(−)-pulegone, the lactonization, iodolactonization, and incorporation of hydroxyl and carbonyl groups were studied, as well.
The most active compounds were (R)-(+)-pulegone (1a) and δ-hydroxy-γ-spirolactones (5S,6R,8S)-(−)-6-hydroxy-4,4,8-trimethyl-1-oxaspiro[4.5]decan-2-one (5b) and (5R,6S,8S)-6-hydroxy-4,4,8-trimethyl-1-oxaspiro[4.5]decan-2-one (6b) derived from (S)-(−)-pulegone (1b). The compounds deterred aphid probing and feeding at preingestional, ingestional, and postingestional phases of feeding.
The preingestional effect of (R)-(+)-pulegone (1a) was manifested as difficulty in finding and reaching the phloem (i.e., prolonged time preceding the first contact with phloem
vessels), a high proportion of probes not reaching beyond the mesophyll layer before first phloem phase, and/or failure to
find sieve elements by 20% of aphids during the 8-hr experiment. The ingestional activity of (R)-(+)-pulegone (1a) and hydroxylactones 5b and 6b resulted in a decrease in duration of phloem sap ingestion, a decrease in the proportion of aphids with sustained sap ingestion,
and an increase in the proportion of aphid salivation in phloem. δ-Keto-γ-spirolactone (5R,8S)-(−)-4,4,8-trimethyl-1-oxaspiro[4.5]decan-2,6-dione (8b) produced a weak ingestional effect (shortened phloem phase). The postingestional deterrence of (R)-(+)-pulegone (1a) and δ-hydroxy-γ-spirolactones (5R,6S,8R)-(+)-6-hydroxy-4,4,8-trimethyl-1-oxaspiro[4.5]-decan-2-one (5a), 5b, (5S,6R,8R)-6-hydroxy-4,4,8-trimethyl-1-oxaspiro[4.5]decan-2-one (6a), 6b, and δ-keto-γ-spirolactone 8b prevented aphids from settling on treated leaves. The trans position of methyl group CH3–8 and the bond C5–O1 in lactone 6b appeared to weaken the deterrent activity in relation to the cis diastereoisomer (5b). 相似文献
99.
Iwona Gajda John Greenman Chris Melhuish Ioannis Ieropoulos 《International Journal of Hydrogen Energy》2013
One of the major limiting factors in the practical implementation of Microbial Fuel Cells is finding efficient and sustainable catalysts for the cathode half reaction, in an attempt to avoid expensive and/or toxic catalysts. The use of phototrophic organisms is one good option since they can act as efficient in-situ oxygenators thus facilitating the cathodic reaction. In the present study, the oxygen production by photosynthetic organisms was shown to be light dependant, which resulted in increasing the power generation by 42%. Furthermore, this study showed that a previously abiotic cathode that turned biotic showed a clear light response with an improved performance of 48%. Oxygen depletion in a water-based cathode can be avoided with the use of photosynthetic biocatalysts, thus providing sustainable operation for MFCs. 相似文献
100.
Iwona Paprocka 《国际生产研究杂志》2013,51(14):4480-4501
The accuracy of prediction and detection capability have a strong influence over the efficiency of the bottleneck, all equipment and the production system. The function of predictive scheduling is to obtain stable and robust schedules for a shop floor. The first objective is to present an innovative maintenance planning and production scheduling method. The approach consists of four modules: a database to collect information about failure-free times, a prediction module of failure-free times, predictive scheduling and rescheduling module, a module for evaluating the accuracy of prediction and maintenance performance. The second objective is to apply the proposed methods for a job shop scheduling problem. Usually, researchers who are concerned about maintenance scheduling do not take unexpected disturbances into account. They assume that machines are always available for processing tasks during the future-planned production time. Moreover, researches use the criteria that are not effective to deal with the situation of unpredicted failures. In this paper, a method based on probability theory is proposed for maintenance scheduling. For unpredicted failures, a rescheduling method is also proposed. The evaluation module which gives information about the degradation of each performance measure and the stability of a schedule is proposed. 相似文献