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51.
The purpose of this paper is to analyze the costs for reducing CO2 emissions in the power-generating sectors in Croatia, the European part of Russia, Macedonia, Serbia and the Ukraine in 2020 by using a linear programming model. The model takes into account the impact of technology learning and is based on the underlying assumptions of the so-called RAINS model frequently used to assess the potential and the costs for reducing air pollution in Europe. The results based on an exogenously given 15 percent reduction target for CO2 emissions show that the marginal cost for switching from a carbon-intense fuel to either a low-carbon or to a renewable energy source differs significantly among the countries. The marginal costs range from 4 to 90€ per ton CO2, and are mainly due to country differences in the availability of renewables, existing technologies and costs. The results also indicate that although it is clear that the Eastern European countries are not homogeneous in terms of CO2 abatement potential and costs, no general conclusions can be made of the region. This may have important implications for future JI/CDM activities. For instance, risk factors such as policy uncertainty and institutional obstacles may become crucial in determining the future allocation of JI/CDM projects across the region. 相似文献
52.
M Ronaghi B Pettersson M Uhlén P Nyrén 《Canadian Metallurgical Quarterly》1998,25(5):876-8, 880-2, 884
The need for a primer hybridization step before sequencing has been eliminated using a stem-loop structure generated by PCR. The loop structure is obtained by careful design of the PCR primer or by cloning the target DNA into a dedicated vector (pRIT 28HP). After solid-phase capture of the PCR product, the loop is formed by elution of the non-bound strand. Here, we show that both the immobilized and the eluted strand can be analyzed using conventional Sanger DNA sequencing and the novel pyrosequencing method as described previously. By using a stem-loop structure as a primer for DNA sequencing, the risk for mispriming is minimized. 相似文献
53.
Genetic typing of HLA class II genes in Swedish populations: application to forensic analysis 总被引:1,自引:0,他引:1
In an attempt to determine the value of DNA based typing of HLA class II loci to forensic analysis, allele and genotype frequencies at DQA1, DQB1, DPB1, and DRB1 were determined in samples from two Swedish populations using hybridization with sequence specific oligonucleotides to PCR amplified DNA. Significant allele frequency differences were observed at the DQB1 and DRB1 loci between the two populations, as well as between one of the Swedish and a Norwegian population. The average heterozygosity varies between 0.74 to 0.91 and the power of discrimination between 0.90 to 0.98, with the highest values obtained for the DRB1 locus. The probability of genotype identity by chance differs on average 2% between the populations. When applied to a paternity case with one parent deceased and a criminal case, typing of class II loci proved in both cases informative. Analyses of DR and DQ genes does not increase the power of discrimination, due to strong linkage, but offers through the reconstruction of putative haplotypes an internal control for the consistency of the typing results at several loci. Typing of the DRB1 and DPB1 loci was found to result in an approximate combined average probability of genotype identity by chance of one in a thousand. 相似文献
54.
MA N?rgaard PS Olsen UG Svendsen G Pettersson 《Canadian Metallurgical Quarterly》1996,62(4):1215-1221
Development of the surgical technique has minimized the incidence of airway problems associated with single as well as sequential bilateral lung transplantation. Although early results are good, long-term results remain unsatisfactory. The main problems after lung transplantation are pulmonary infections and the bronchiolitis obliterans syndrome. The bronchiolitis obliterans syndrome is usually considered to be chronic rejection, but a multifactorial genesis including airway ischemia has been suggested. We reviewed the literature relevant to direct bronchial artery revascularization during lung transplantation. Although information is limited, there are good reasons to believe that reestablishment of the dual blood supply to the transplanted lung is beneficial not only for healing of the airway anastomoses, but also for the airway and the lung responses to pathologic conditions. In small series, methods of bronchial artery revascularization have proved successful and have been associated with good early results. We believe it is justified to test the impact of direct bronchial artery revascularization on outcome after lung transplantation in large clinical series. 相似文献
55.
Due to high costs, a fire resistance test of a load-bearing structural element is usually limited to one test specimen — in a few countries, to two test specimens. Accordingly, there are no possibilities of evaluating the test results statistically.For a single test specimen, the actual quality of the structural material represents a random sample from a wide variety. This applies also to the initial imperfections of the structural elements. In consequence of this, a standard fire resistance test is generally carried out on a test specimen with a load-bearing capacity which is greater — most often significantly greater — than the load-bearing capacity related to the characteristic values of the mechanical material strength and of the imperfections of the structural member. In current practice, no corrections of the test results with respect to this are made.In a conventional analytical design, a determination of the load-bearing capacity of a structure at room temperature conditions is based on the characteristics values of the strength and imperfections. Extended to a structural fire engineering design, this procedure will give an analytically determined fire resistance of a load-bearing structural element which is lower — normally essentially lower — than the corresponding value derived from a standard fire resistance test.Available methods for a simplified calculation of the temperature of fire exposed steel structures are, as a rule, based on the assumption of a uniformly distributed temperature structure at each time of fire exposure. The ECCS Recommendations for an analytical design of steel structures exposed to a standard fire follow this kind of approach. For certain types of steel structures, for example, beams with a slab on the upper flange, a considerable temperature variation arises over the cross section as well as in the longitudinal direction during a fire resistance test. A simplified, analytical method, which neglects this influence, gives a further underestimation of the fire resistance in relation to the corresponding result obtained in a standard fire resistance test.The described discrepancies between an analytical and an experimental determination of the fire resistance are further discussed and analysed in Sections 2 and 3, with particular reference to different types of steel structures. The discussion is focussed on the loading and restraint conditions, the scatter of material properties and geometrical imperfections, and the temperature variation over the structure or structural element. The discussion is summarized in Section 4 and alternative methods of correction are outlined briefly for obtaining an improved consistency between the analytical and the experimental approaches.In Section 5, one of these methods is further developed to a design basis which can be applied easily in practice. Principally, the method is characterized by a correction of the analytically determined load-bearing capacity, based on the characteristic value of the structural material properties, the characteristic value of the imperfections of the structure, and a uniformly distributed steel temperature across and along the structure. Two different sequences of the design procedure are dealt with, defined according to Figs. 10 and 11. The resultant correction factors, ? and κ, belonging to the respective sequences, are given by Figs. 8 and 12 for columns, isostatic beams, and hyperstatic beams. The straight line curves in Figs. 9 and 13 show corresponding, simplified relationships for the ? and κ factors.The derived method of correction must be characterized as an approximate approach. This is in consequence of the present state of knowledge, which does not allow a solution of high accuracy. The task to develop a correction procedure which leads to improved consistency between an analytically and an experimentally determined fire resistance, should also be seen in the context of the inadequate reproducibility of the standard fire resistance test. 相似文献
56.
The effect of intracarotid infusion of the bradykinin analog, RMP-7, on blood-to-tumor and blood-to-brain transport of three cytokines were investigated. Wistar rats with RG2 gliomas were utilized and a unidirectional transfer constant, Ki, was determined using quantitative autoradiography. Interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), and interleukin-2 (IL-2) were labeled with 125Iodine for quantitative transport studies using autoradiography. Radiolabeled cytokines were injected as an intravenous bolus. Intracarotid infusion of RMP-7 (0.1 microgram kg-1 min-1) increased the selective transport to tumors of IFN-gamma by 3.97-fold (p < 0.005), of TNF-alpha by 5.30-fold (p < 0.005), and of IL-2 by 4.34-fold (p < 0.005), compared to intracarotid saline infusion. To determine whether the increased IFN-gamma or TNF-alpha transport to tumors with RMP-7 could enhance expression of intercellular adhesion molecule 1 (ICAM-1) in tumors, ICAM-1 expression in RG2 glioma was evaluated by immunohistochemistry. Both IFN-gamma and TNF-alpha increased ICAM-1 expression of RG2 cells in vitro. In vivo, intracarotid infusion of IFN-gamma combined with RMP-7 significantly enhanced ICAM-1 expression in intracerebral RG2 gliomas compared to infusion of IFN-gamma without RMP-7. Expression of ICAM-1 was not enhanced by TNF-alpha combined with RMP-7. Intracarotid infusion of RMP-7 is a novel method of cytokines delivery to brain tumors. 相似文献
57.
M Fader L Pettersson R Brooks G Dean M Wells A Cottenden J Malone-Lee 《Canadian Metallurgical Quarterly》1997,6(7):359, 362-4, 366-7
Catheter valves are an alternative to leg bags for urine drainage, but no studies have yet been published which have compared the performance of different valves. This study was undertaken to evaluate the performance of the seven catheter valves available on the UK market in April 1996. The study was carried out by the Continence Products Evaluation (CPE) Network funded by the Medical Devices Agency (Department of Health). Each valve type was tested for 1 week by 19-36 cognitively unimpaired and manually dextrous subjects recruited from 11 test centres. At the end of each week, subjects completed an evaluation form (based on a three-point rating scale) to record product performance. The same catheter valves were also tested for ease of opening/closing by 33 subjects (mostly catheter users) who had some manual impairment. Performance scores varied widely between products. It was found that, to be successful, a valve needs to be easy to manipulate, leak-free, comfortable and inconspicuous. Prescribers need to be aware of the strengths and limitations of different valves for appropriate product selection. 相似文献
58.
Kjell Pettersson 《Journal of Nuclear Materials》1975,56(1):91-102
The low-cycle fatigue properties of specimens of recrystallized Zircaloy-2 cladding have been investigated using a bend-testing rig at 20, 250, 300, 350 and 400°C. The results followed the Coffin-Manson law for low-cycle fatigue at all temperatures. Irradiated specimens were tested at 20 and 300°C. At 20°C the life of irradiated specimens was shorter than that of unirradiated specimens, whilst at 300°C the irradiated specimens fall on the same Coffin-Manson plot as the unirradiated specimens. Generally the number of cycles to failure in the present investigation was a factor of three smaller than in other investigations using push-pull testing machines. Fracture surfaces were investigated in a scanning electron microscope in order to determine the characteristic features of low-cycle fatigue failures. Twins found along the path of the fatigue cracks were explained as being a consequence of the cracks rather than as promoters of crack propagation. 相似文献
59.
Closure of minor defects in the hard palate can be done with local flaps. There is often a risk of perforation of the reconstructed area. In the case reported this complication was obvious due to a large, thin, flap-covered area. In strengthening the reconstruction fascia lata and Surgicel was used. The postoperative result was excellent and the rehabilitation of the patient was without complications. 相似文献
60.