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41.
QUALIFICATION OF HALS COMPOUNDS A complex method of examination has been developed suitable for the qualification of light stabilizers; by this method, according to experience, the efficacy of HALS compounds can be extensively and expediently characterized. Several light stabilizers of the HALS-type were examined and qualified, used alone or together with a UV-absorber. It has been found that, when selecting the appropriate structure for a given polymer, the weatherability of polyolefine foils is effectively increase to six-eightfold; the increase is even tenfold when the stabilizer is combined with a benzophenone-type compound. As a utilization of these experiences, a contract with the industry, led to the production of an LDPE based agricultural foil with a life-time of several years. 相似文献
42.
K Mazuruk TJ Schoen GJ Chader T Iwata IR Rodriguez 《Canadian Metallurgical Quarterly》1996,1305(3):151-162
Monoclonal antibodies (MoAbs) raised against Trypanosoma cruzi microsomal fraction (Mc) and cross-reactive with mammalian tissues were used to evaluate the ability of cross-reactive T. cruzi antigens to induce an immune response in Chagas' disease. Thus, we studied the ability of sera from Chagas' disease patients (CDP) with different degrees of cardiac dysfunction to block the immune recognition of these MoAb to the target antigen determining for each serum an inhibition index (II). By means of this approach we inferred that blocking of monoclonal antibody binding to T. cruzi microsomes by subjects' serum represents antibodies with the same reactivity. After serological and medical examinations, individuals were separated into the following groups: Chagas' disease patients without manifest cardiac involvement (CDP-0), CDP with suspected or borderline cardiac disease (CDP-1), CDP with moderate myocardial dysfunction (CDP-2), CDP with overt cardiac dysfunction (CDP-3) and controls including healthy subjects (HS) and patients with idiopathic myocarditis (IMP). The reactivity between MoAb 5F2 and its target antigen was significantly (p < 0.05) inhibited by sera from CDP irrespective of the clinical stage [CDP: n = 46, 50 +/- 20, mean II +/- SD: control: n = 16, 18 +/- 8]. Moreover, 5F2 was able to distinguish (p < 0.05) sera from CDP with mild disease (CDP clinical grade 0/1: n = 26, 34 +/- 18) from that of CDP with severe disease (CDP clinical grade 2/3: n = 20, 67 +/- 7). Moreover, the inhibitory capacity of sera from asymptomatic CDP (CDP-0) correlated with patients age (r = 0.66, p < 0.05). CDP-0 below or equal 40 years of age had results (n = 15, 25 +/- 13) comparable (p > 0.05) to that of controls while mean inhibition of CDP-0 over 40 years of age (n = 5, 60 +/- 5) was indistinguishable (p > 0.05) from that of patients with severe disease. Competitive assay with MoAb 5A9B11 also showed significant differences (p < 0.05) between sera from CDP (n = 46, 46 +/- 24) and controls (n = 13, 5 +/- 5). On the contrary, the differences observed between CDP with different cardiac involvement was not significant (mild: n = 26, 31 +/- 22; severe: n = 20, 66 +/- 11). However a thorough study of data from asymptomatic sera revealed the existence of two levels of reactivity, with low and high capacity to inhibit the reaction of 5A9B11 against Mc. On the contrary, CDP sera showed a blocking activity for 1A10C11 comparable to that of controls (CDP: n = 25, 19 +/- 9; control: n = 12, 14 +/- 6). Some cross-reactive MoAbs recognized epitopes partially composed of carbohydrates. Interestingly, 5F2 and 5A9B11 epitopes did not appear to have carbohydrates moieties. In summary, immunoinhibition assays revealed differences in the immune response of chronic chagasic patients against parasite epitopes. These results have opened the possibility to identify a prognosis marker of the disease suggesting the clinical utility of monitoring levels of these anti-Mc antibodies in patients with chronic Chagas' disease. 相似文献
43.
Using survey data from 2,000 low-income adult respondents in each of five states, this DataWatch assesses how uninsured, low-income adults differ from low-income adults who have public or private insurance and how Medicaid expansions have affected insurance coverage patterns across states with different eligibility policies. Findings show that the proportion of low-income uninsured adults is two to three times higher in states that have not expanded Medicaid eligibility beyond relatively low welfare levels. Compared with persons who have either Medicaid or private insurance, uninsured persons report more difficulties getting needed care, are less likely to have a regular provider, and rate the care they do receive as lower quality. 相似文献
44.
A Gillissen A Bartling S Schoen G Schultze-Werninghaus 《Canadian Metallurgical Quarterly》1997,175(4):235-242
Fc gamma receptors (Fc gamma R) on white blood cells and the Duffy blood group antigens on red blood cells are coded for on the long arm of chromosome 1. They appear in different allotypic forms: the high responder/low responder (HR/LR) forms of Fc gamma RIIa, the alloantigens NA1 and NA2 of Fc gamma RIIIb and the Duffy blood group antigens Fya and Fyb. The aim of this study was to analyze possible linkage disequilibria between these allotypic immunomodulatory receptors, and thus provide evidence for the existence of a hypothetical gene complex. The Duffy phenotype was determined by the indirect antiglobulin test, NA1/NA2 phenotypes by the granulocyte agglutination test and the HR/LR polymorphism by an immunophagocytosis assay. Two haplotypes were found to be in linkage disequilibrium. For the haplotype NA2, Fyb we calculated a delta-value of -0.07 and for the haplotype NA1, HR we obtained a delta-value of -0.02. 相似文献
45.
DA Coviello BJ Maron P Spirito H Watkins HP Vosberg L Thierfelder FJ Schoen JG Seidman CE Seidman 《Canadian Metallurgical Quarterly》1997,29(3):635-640
OBJECTIVES: We studied the clinical and genetic features of familial hypertrophic cardiomyopathy (FHC) caused by an Asp175Asn mutation in the alpha-tropomyosin gene in affected subjects from three unrelated families. BACKGROUND: Correlation of genotype and phenotype has provided important information in FHC caused by beta-cardiac myosin and cardiac troponin T mutations. Comparable analyses of hypertrophic cardiomyopathy caused by alpha-tropomyosin mutations have been hampered by the rarity of these genetic defects. METHODS: The haplotypes of three kindreds with FHC due to an alpha-tropomyosin gene mutation, Asp175Asn, were analyzed. The cardiac histopathologic findings of this mutation are reported. Distribution of left ventricular hypertrophy in affected members was assessed by two-dimensional echocardiography, and patient survival rates were compared. RESULTS: Genetic studies defined unique haplotypes in the three families, demonstrating that independent mutations caused the disease in each. The Asp175Asn mutation caused cardiac histopathologic findings of myocyte hypertrophy, disarray and replacement fibrosis. The severity and distribution of left ventricular hypertrophy varied considerably in affected members from the three families (mean maximal wall thickness +/- SD: 24 +/- 4.5 mm in anterior septum of Family DT; 15 +/- 2.7 mm in anterior septum and free wall of Family DB; 18 +/- 2.1 mm in posterior septum of Family MI), but survival was comparable and favorable. CONCLUSIONS: Nucleotide residue 579 in the alpha-tropomyosin gene may have increased susceptibility to mutation. On cardiac histopathologic study, defects in this sarcomere thin filament component are indistinguishable from other genetic etiologies of hypertrophic cardiomyopathy. The Asp175Asn mutation can elicit different morphologic responses, suggesting that the hypertrophic phenotype is modulated not by genetic etiologic factors alone. In contrast, prognosis reflected genotype; near normal life expectancy is found in hypertrophic cardiomyopathy caused by the alpha-tropomyosin mutation Asp175Asn. 相似文献
46.
Schoen E. Smith R.G. Buchanan B.G. 《IEEE transactions on pattern analysis and machine intelligence》1988,14(12):1771-1791
The authors propose a model for an intelligent assistant to aid in building knowledge-based systems (KBSs) and discuss a preliminary implementation. The assistant participates in KBS construction, including acquisition of an initial model of a problem domain, acquisition of control and task-specific inference knowledge, testing and validation, and long-term maintenance of encoded knowledge. The authors present a hypothetical scenario in which the assistant and a KBS designer cooperate to create an initial domain model and then discuss five categories of knowledge the assistant requires to offer such help. They discuss two software technologies on which the assistant is based: an object-oriented programming language, and a user-interface framework 相似文献
47.
An acoustooptic loss modulator and Eastman #5 saturable absorbing dye are used to stably mode lock a TEM00 Nd:phosphate glass oscillator. This hybrid approach has enabled reliable generation of ∼ 6 ps duration pulses largely free of occurrences of satellite pulse structure. 相似文献
48.
A hybrid free-electron laser device (called a GYROFEL), employing axial bunching in a solenoidal field configuration, has been analyzed to determine potential operational power levels. A small signal gain model was utilized to estimate the intracavity electric field strengths attained at equilibrium in such a device. The results indicate that out-coupled power levels approaching 1 MW might be achievable for electron beams near the 1 MeV energy range. 相似文献
49.
33 years after vesiculography using the X-ray contrast remedy Thorotrast on transurethral way in a patient with chronic prostatitis a carcinoma developed in the region of the vesical neck. Histologically the tumour imposed now as a differentiated urothelium carcinoma of medium degree. By autoradiography in the region of the tumour structures radioactive Thorotrast could be proved. On account of the close topographical relations and the long time of latency the development of the carcinoma seems to be ascertained by the then application of Thorotrast. The connections are discussed. 相似文献
50.
Engineers and researchers working on the development of airborne wind energy systems (AWES) still rely on oversimplified wind speed approximations and coarsely sampled reanalysis data because of a lack of high‐resolution wind data at altitudes above 200 m. Ten‐minute average wind speed LiDAR measurements up to an altitude of 1100 m and data from nearby weather stations were investigated with regard to wind energy generation and impact on LiDAR measurements. Data were gathered by a long‐range pulsed Doppler LiDAR device installed on flat terrain. Because of the low overall carrier‐to‐noise ratio, a custom‐filtering technique was applied. Our analyses show that diurnal variation and atmospheric stability significantly affect wind conditions aloft which cause a wide range of wind speeds and a multimodal probability distribution that cannot be represented by a simple Weibull distribution fit. A better representation of the actual wind conditions can be achieved by fitting Weibull distributions separately to stable and unstable conditions. Splitting and clustering the data by simulated surface heat flux reveals substate stratification responsible for the multimodality. We classify different wind conditions based on these substates, which result in different wind energy potential. We assess optimal traction power and optimal operating altitudes statistically as well as for specific days based on a simplified AWES model. Using measured wind speed standard deviation, we estimate average turbulence intensity and show its variation with altitude and time. Selected short‐term data sets illustrate temporal changes in wind conditions and atmospheric stratification with a high temporal and vertical resolution. 相似文献