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61.
Increasing production and use of fullerene-based nanomaterials underscore the need to determine their mobility in environmental transport pathways and potential ecological exposures. This study investigated the transport of two fullerenes (i.e., aqu/C60 and water-soluble C60 pyrrolidine tris-acid [C60 PTA]) in columns packed with model porous media (Iota quartz and Ottawa sand) and a sediment from Call’s creek under saturated and unsaturated steady-state flows. The fullerenes had the least retention in Iota quartz, and the greatest retention in the sediment at near neutral pH, correlating with the degree of grain surface chemical heterogeneity (e.g., amorphous Al hydroxides concentration increasing in the order of Iota quartz < Ottawa sand < sediment). Surface roughness was elucidated as another important factor responsible for the greatest fullerene retention in the sediment. In accordance with the XDLVO energy calculations, C60 PTA was less retained than aqu/C60 at near neutral pH, due to its greater hydrophilicity measured by tolune-water partition coefficient, as well as smaller particle sizes revealed by atomic force microscopy. Fullerene retention exhibited a strong dependency on solution pH that could be explained partly by the pH-dependent surface charge of fullerenes and grain surface, and partly by increased hydrophobicity of C60 PTA when solution pH approaches its isoelectric point (IEP). Finally, fullerene retention was enhanced in unsaturated media, implying that fullerenes may be more attenuated in the vadose zone than in groundwater. 相似文献
62.
Jie Kang Keshari M. Thakali Chenghui Xie Miwako Kondo Yudong Tong Boxin Ou Gitte Jensen Marjorie B. Medina Alexander G. Schauss Xianli Wu 《Food chemistry》2012
There are two predominant palm tree species producing edible fruit known as “açaí” found widely dispersed through the Amazon: Euterpe oleracea Mart. and Euterpe precatoria Mart. They differ from each other in terms of how the plants grow and their phytochemical composition. E. oleracea (EO) has received considerable attention as a “super fruit” because of its high antioxidant capacity, while studies on E. precatoria (EP) remain rare. In this study, the antioxidant and anti-inflammatory activities of EP fruit pulps were evaluated by different assays including a series of oxygen radical absorbance capacity (ORAC) based assays, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, the cell-based antioxidant protection in erythrocyte (CAP-e) assay, as well as the nuclear factor-kappa B (NF-κB) secreted embryonic alkaline phosphatase (SEAP) assay. Total phenolics were also measured as an indication of the total phenol content. For comparative purposes, the EO fruit pulp was included. The antioxidant capacity of the EP fruit pulp was determined to be superior to the EO fruit pulp in every chemical based assay. In the cell-based CAP-e assay, the EP fruit pulp showed a dose-dependent inhibition against oxidative damage with an IC50 of 0.167 g/l. In the SEAP reporter assay, the EP fruit pulp polyphenol-rich extracts inhibited lipopolysaccharide (LPS)-induced NF-κB activation by 23% (p < 0.05) at 20 μg/ml, whereas the extract of the EO fruit pulp did not show a significant inhibitory effect at comparable doses. In addition, carotenoids were quantified for the first time in EP, since EP has high scavenging capacity against singlet oxygen. 相似文献
63.
Burk Linnea R.; Armstrong Jeffrey M.; Goldsmith H. Hill; Klein Marjorie H.; Strauman Timothy J.; Costanzo Phillip; Essex Marilyn J. 《Canadian Metallurgical Quarterly》2011,25(1):1
Adolescent alcohol use is common and has serious immediate and long-term ramifications. While concurrent individual and context factors are robustly associated with adolescent alcohol use, the influence of early childhood factors, particularly in interaction with child sex, are less clear. Using a prospective community sample of 362 (190 girls), this study investigated sex differences in the joint influence of distal childhood and proximal adolescent factors on Grade 10 alcohol use. All risk factors and two-way early individual-by-context interactions, and interactions of each of these with child sex, were entered into the initial regression. Significant sex interactions prompted the use of separate models for girls and boys. In addition to the identification of early (family socioeconomic status, authoritative parenting style) and proximal adolescent (mental health symptoms, deviant friends) risk factors for both girls and boys, results highlighted important sex differences. In particular, girls with higher alcohol consumption at Grade 10 were distinguished by the interaction of early temperamental disinhibition and exposure to parental stress; boys with higher alcohol consumption at Grade 10 were distinguished primarily by early temperamental negative affect. Results have implications for the timing and type of interventions offered to adolescents. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
64.
Heat Intensity and Warmed-over Flavor in Precooked Chicken Patties Formulated at 3 Fat Levels and 3 Pepper Levels 总被引:1,自引:0,他引:1
Margaret E. Emrick Marjorie P. Penfield Craig D. Bacon Riette V.L. van L aack Clark J. Brekke 《Journal of food science》2005,70(9):S600-S604
ABSTRACT: Heat intensity and warmed-over flavor (WOF) were evaluated to determine the effects the composition of precooked, chopped, and formed chicken patties would impart on the perception of red pepper heat and the development of oxidation. Patties were formulated at 5%, 7%, and 9% fat with marinade formulated at 0%, 0.2%, and 0.4% pepper. A trained sensory panel assessed the heat intensity over 3 min using time intensity evaluation. Heat and WOF intensities of the patties were measured 5 times over a 9-wk storage period. As fat level increased, total time intensity and time to maximum heat intensity increased. Patties formulated at 7% and 9% fat were perceived to be more intense in heat than the 5% fat patties. Patties formulated at 0.2% and 0.4% pepper had less intense WOF than patties with 0% pepper level. Chemical measurement of oxidation (thiobarbituric acid numbers) indicated that increasing pepper content decreased malonaldehyde content. Incorporation of pepper into a chopped and formed meat product requires a higher pepper content at lower fat levels to impart the same level of heat intensity as in patties of higher fat level. Increasing the pepper content also will aid in decreasing production of malonaldehyde in a precooked meat product, thereby reducing the intensity of warmed-over flavor as perceived by the consumer. 相似文献
65.
66.
Shisslak Catherine M.; Crago Marjorie; Neal Mary E.; Swain Barbara 《Canadian Metallurgical Quarterly》1987,55(5):660
Eating disorders have increased dramatically over the past two decades, but the primary prevention of these disorders has received little attention. This article summarizes our current understanding of anorexia nervosa and bulimia and offers some suggestions for the primary prevention of these disorders at the individual, family, and community levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
Kolb Daniel L.; Beutler Larry E.; Davis Carl S.; Crago Marjorie; Shanfield Stephen B. 《Canadian Metallurgical Quarterly》1985,22(4):702
Investigated the relationship between pretherapy patients and process variables and change in 91 19–54 yr old adults who received psychotherapy from 26 trainees at a university teaching hospital. Pretherapy measures included Rotter's Internal–External Locus of Control Scale, the Eysenck Personality Inventory, and the SCL-90 (Revised). Upon termination of therapy, Ss completed the SCL-90, the Barrett-Lennard Relationship Inventory—Form OS64, and a personal evaluation form; therapists completed a psychotherapy process inventory and a discharge summary. Results indicate that process variables rather than preexisting S traits were the best predictors of outcome. Therapist ratings of Ss' involvement in therapy were the best single predictor of symptomatic change. Variables differentiating dropouts from remainers were also investigated. Few outcome differences were observed between Ss who remained in and Ss who dropped out of therapy. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
M Davidovitch LK Rubengtein GN Pham RJ Isaacson 《Canadian Metallurgical Quarterly》1995,29(8):487-491
Patterns of rye rDNA organization in interphase nuclei were studied through the use of in situ hybridization in spreads of root meristem cells from plants with and without B chromosomes (Bs). In cells from plants without Bs each rDNA locus is organized as a single perinucleolar knob of condensed chromatin with decondensed chromatin inside the nucleolus. In plants with Bs there is a marked modification of the pattern, found in more than 23% of nuclei, which involves several regions of condensed chromatin interspersed with decondensed chromatin inside the nucleolus. This B-induced alteration in rDNA interphase organization suggests a change in expression of the rRNA genes located on the A chromosomes probably related to the reduction in nuclear RNA observed previously in plants with Bs. The influence of the Bs on the expression of A chromosome genes, through rearrangement of interphase chromatin, could provide the basis of an explanation for some of the known phenotypic effects of B chromosomes in rye. 相似文献
69.
Shisslak Catherine M.; Crago Marjorie; Schnaps Laura; Swain Barbara 《Canadian Metallurgical Quarterly》1986,23(4):598
Describes interactional group therapy for anorexic and bulimic women, as it was used for 12 groups (with 4–8 Ss each) conducted over 4.5 yrs. Bulimics and anorexics were combined because it is believed that the 2 types of eating-disordered patients have much that they can learn from each other. Group themes particularly relevant to eating-disordered women are discussed, including confidentiality, sexuality, commonalities between the 2 types, and transference. Stages in the evolution of the group and strategies for facilitating group process are reviewed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.