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51.
Uneus L. Artursson T. Mattsson M. Ljung P. Wigren R. Martensson P. Holmberg M. Lundstrom I. Spetz A.L. 《IEEE sensors journal》2005,5(1):75-81
Metal insulator silicon carbide field-effect transistor sensors, metal-oxide sensors, and a linear Lambda sensor in an electronic nose was used to measure on-line in hot flue gases from a boiler. Flue gas from a 100-MW pellets-fuelled boiler has been used to feed the experimental setup. Several reference instruments, which measure the flue gases in parallel to the sensor array, are connected to the electronic nose. Data was collected during six weeks and then evaluated. Using principal component analysis as the data evaluation method, different operating modes for the boiler have been identified in the data set. The different modes could be described in terms of high or low O/sub 2/ and CO concentration. Furthermore, we have shown that it seems possible to use a sensor array to determine the operating mode of the boiler and, by partial least-squares models, measure the CO concentration when the boiler operates in its optimum mode. 相似文献
52.
AM Gülmezoglu K Mahomed GJ Hofmeyr VC Nikodem T Kramer 《Canadian Metallurgical Quarterly》1996,24(6):687-691
Endovascular treatment methods that are largely catheter/guidewire-based permit treatment of a variety of vascular lesions from remote access sites in a minimally invasive manner. Because these endovascular technologies have intrinsic appeal to patients and physicians, they may, if proved safe and effective, replace a substantial proportion of current vascular surgical procedures. This change will have a substantial impact on the specialties involved in their development and use, that is, vascular surgery and interventional radiology (which in this discussion includes other interventional specialists devoted to peripheral vascular disease management). The relationship between these previously distinct specialties must also be influenced greatly by the introduction of endovascular technologies, the use of which requires skills that overlap the specialties. This paper considers several possible approaches for dealing with the altered interspecialty relationships that will result if new endovascular treatment methods prove to be safe and effective. Because the development and use of these endovascular technologies require the skills and talents of vascular surgeons and interventional radiologists (or other interventionalists), a collaborative, multispecialty approach to the use of endovascular technologies is recommended as the most reasonable and optimal for patient care. Although this approach may not be applicable for every environment, it is the one most likely to minimize costs and turf battles, particularly if interspecialty conflict can be minimized by collaboration and compromises developed by a conjoint executive committee representing the leadership of the involved specialty societies. 相似文献
53.
RC MacPhail HA Tilson VC Moser GC Becking V Cuomo E Frantík BM Kulig G Winneke 《Canadian Metallurgical Quarterly》1997,18(4):925-928
Numerous events over several years culminated in recognition of the need to explicitly evaluate the nervous system as a potential target for environmental chemicals. Based on recommendations from several international expert panels, the International Programme on Chemical Safety (IPCS) sponsored the Collaborative Study on Neurobehavioral Screening Methods. A Steering Committee was created to oversee the project, develop the testing protocol, recruit participating laboratories and review and analyze the data. The protocol specified the tests, the chemicals (supplied from a common source) and the exposure conditions (acute and repeated dosing). Test methods were based upon existing practices in toxicological screening as well as recent advances in neurotoxicity screening. Chemicals were selected to produce different profiles of neurobehavioral effects. Considerable latitude was afforded the participating laboratories in the choice of several key variables (e.g., strain of rat, testing device for motor activity assessment) that could potentially affect the results of the experiments. The approach therefore provided a standardized yet flexible protocol for evaluating the reproducibility of neurobehavioral screening data in diverse laboratory settings. 相似文献
54.
IF Pollack RC DaRosso PL Robertson RL Jakacki JR Mirro J Blatt S Nicholson RJ Packer JC Allen A Cisneros VC Jordan 《Canadian Metallurgical Quarterly》1997,3(7):1109-1115
Recent studies have indicated that the proliferation of malignant gliomas is in part dependent on excessive activation of protein kinase C (PKC)-mediated pathways. Conversely, inhibiting PKC may provide a novel approach for blocking glioma growth. The antiestrogen tamoxifen, a moderately potent PKC inhibitor, has been shown in vitro to block the proliferation of malignant glioma cell lines at concentrations several-fold higher than those typically attained during the treatment of breast cancer; such serum concentrations may be achieved with doses > 40 mg/m2 b.i.d. The safety and efficacy of these high doses for producing disease control in patients with malignant gliomas has recently been noted anecdotally, although a rigorous study of this agent has been lacking. To address this issue, we examined the safety and efficacy of high-dose tamoxifen in a series of children with malignant gliomas that had progressed after conventional therapy. An initial group was treated with 60 mg/m2 p.o. b.i.d. and a second group with 100 mg/m2 b.i.d. Steady-state serum tamoxifen and metabolite levels were measured in most patients. Toxicity with the regimen was minimal; two patients treated at the higher dose required reduction to the lower dose because of asymptomatic prolongation of the QT interval on an electrocardiogram. Although none of the patients exhibited clear-cut tumor regression, 4 of 14 patients had stabilization of previously progressive disease for at least 3 months; the longest survivor lived for 17 months after beginning tamoxifen. The moderate efficacy of this agent in otherwise end-stage disease coupled with its low toxicity and the relative ease of oral administration provides a rationale for proceeding with larger studies of this agent in patients with malignant gliomas, possibly as a means for potentiating the effects of conventional chemotherapeutic agents, which to date have shown limited efficacy in the treatment of these tumors. 相似文献
55.
A Nystuen H Costeff ON Elpeleg N Apter B Bonné-Tamir H Mohrenweiser N Haider EM Stone VC Sheffield 《Canadian Metallurgical Quarterly》1997,6(4):563-569
Iraqi-Jewish optic atrophy plus is an autosomal recessive condition characterized by infantile optic atrophy, an early onset movement disorder, and 3-methylglutaconic aciduria. Other features include spastic paraplegia, mild ataxia, mild cognitive deficiency and dysarthria. This disorder was identified in inbred Iraqi-Jewish kindreds in which relationships between most of the affected individuals were unknown. In this study we identify linkage to chromosome 19q13.2-q13.3 by using a DNA pooling strategy to perform a genome wide screen followed by a high density search for shared segments among affected individuals in candidate regions identified in the initial genome wide screen. A significantly high positive lod score of 6.14 at zero recombination was obtained for the CTG repeat in the 3' untranslated region of the myotonic dystrophy protein kinase gene. The existence of multiple recombinant individuals indicates the disease interval can be further narrowed with additional markers. Linkage disequilibrium was seen in six polymorphic markers across a 1 Mb interval. This region is well characterized and contains several candidate genes. 相似文献
56.
57.
Holmberg A Fogel J Albertsson E Fick J Brown JN Paxéus N Förlin L Johnsson JI Larsson DG 《Journal of hazardous materials》2011,187(1-3):596-599
Citalopram is one of several selective serotonin reuptake inhibitors (SSRIs) commonly found in treated sewage effluents. Accordingly, there are concerns about possible adverse effects of SSRIs on aquatic organisms, particularly behavioural effects similar to those associated with SSRI use in humans. Rainbow trout fry and adult male guppies were therefore exposed to waterborne citalopram, ranging from environmentally relevant to high concentrations (1, 10, 100 μg/L) for 3-7 days. Under these experimental conditions citalopram does not appear to cause significant effects on aggression in rainbow trout fry or on sexual behaviour in male guppies. This may be explained by a relatively low uptake of citalopram from water to fish. 相似文献
58.
The use of thematic content of the play of children in therapy is a common aspect to play therapy and an integral part of Thematic Play Therapy. In this project, the researchers investigated the possibility that gender and trauma history influence the play themes of children in therapy. Using the Benedict Play Theme Analysis System (BPTAS), a study of themes demonstrated by 44 children (aged 39–63 mo) participating in therapy through Head Start was conducted. The data were analyzed by comparing equally numbered groups of gender alone (male vs female), trauma history alone (attachment trauma vs attachment trauma plus exposure to violence in the history) and a combination of the possible influences (gender and trauma history). Results indicate that gender and trauma histories, as well as a possible interaction of the two influences, impact the frequency and types of themes that children play in therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
60.
SD Gettings RA Lordo KL Hintze DM Bagley PL Casterton M Chudkowski RD Curren JL Demetrulias LC Dipasquale LK Earl PI Feder CL Galli SM Glaza VC Gordon J Janus PJ Kurtz KD Marenus J Moral WJ Pape KJ Renskers LA Rheins MT Roddy MG Rozen JP Tedeschi J Zyracki 《Canadian Metallurgical Quarterly》1996,34(1):79-117
The CTFA Evaluation of Alternatives Program is an evaluation of the relationship between data from the Draize primary eye irritation test and comparable data from a selection of promising in vitro eye irritation tests. In Phase III, data from the Draize test and 41 in vitro endpoints on 25 representative surfactant-based personal care formulations were compared. As in Phase I and Phase II, regression modelling of the relationship between maximum average Draize score (MAS) and in vitro endpoint was the primary approach adopted for evaluating in vitro assay performance. The degree of confidence in prediction of MAS for a given in vitro endpoint is quantified in terms of the relative widths of prediction intervals constructed about the fitted regression curve. Prediction intervals reflect not only the error attributed to the model but also the material-specific components of variation in both the Draize and the in vitro assays. Among the in vitro assays selected for regression modeling in Phase III, the relationship between MAS and in vitro score was relatively well defined. The prediction bounds on MAS were most narrow for materials at the lower or upper end of the effective irritation range (MAS = 0-45), where variability in MAS was smallest. This, the confidence with which the MAS of surfactant-based formulations is predicted is greatest when MAS approaches zero or when MAS approaches 45 (no comment is made on prediction of MAS > 45 since extrapolation beyond the range of observed data is not possible). No single in vitro endpoint was found to exhibit relative superiority with regard to prediction of MAS. Variability associated with Draize test outcome (e.g. in MAS values) must be considered in any future comparisons of in vivo and in vitro test results if the purpose is to predict in vivo response using in vitro data. 相似文献