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111.
The fermentation of bread and cake dough was monitored on-line by two types of volumetric measurements and by magnetic resonance imaging (MRI). The volumetric measurements enabled independent determination of the actual dough volume and the amount of carbon dioxide that permeated out of the dough. MRI allowed us to obtain an insight into the developing dough and to observe the pore structure during proofing. Due to the non-destructive and non-invasive character of the methods, no sample preparation was necessary, and the fermentation process was not influenced by the measurements. Both methods provided results that were in accordance with each other. The data were used to derive formal reaction-kinetic data for the course of the fermentation process in bread and cake doughs. 相似文献
112.
Bartonella-associated infections 总被引:1,自引:0,他引:1
Bartonella-associated infections occur in immunocompetent and immunocompromised patients. The spectrum of diseases caused by Bartonella species has expanded and now includes cat-scratch disease, bacillary angiomatosis, bacillary peliosis, bacteremia, endocarditis, and trench fever. Most Bartonella-associated infections that occur in North America and Europe are caused by B. henselae or B. quintana. The domestic cat serves as the major reservoir for B. henselae; the reservoir for the modern day B. quintana infection remains unknown. Methods used to diagnose Bartonella-associated infections include histopathologic analysis of biopsy specimens, culture of tissue samples, blood culture, and serology. Available data on treatment of Bartonella-associated infections remain relatively sparse but would suggest that erythromycin or doxycycline provide the best responses. 相似文献
113.
M. L. Clark A. M. Bachand J. M. Heiderscheidt S. A. Yoder B. Luna J. Volckens K. A. Koehler S. Conway S. J. Reynolds J. L. Peel 《Indoor air》2013,23(2):105-114
Few studies have evaluated the cardiovascular‐related effects of indoor biomass burning or the role of characteristics such as age and obesity status, in this relationship. We examined the impact of a cleaner‐burning cookstove intervention on blood pressure among Nicaraguan women using an open fire at baseline; we also evaluated heterogeneity of the impact by subgroups of the population. We evaluated changes in systolic and diastolic blood pressure from baseline to post‐intervention (range: 273–383 days) among 74 female cooks. We measured indoor fine particulate matter (PM2.5; N = 25), indoor carbon monoxide (CO; N = 32), and personal CO (N = 30) concentrations. Large mean reductions in pollutant concentrations were observed for all pollutants; for example, indoor PM2.5 was reduced 77% following the intervention. However, pollution distributions (baseline and post‐intervention) were wide and overlapping. Although substantial reductions in blood pressure were not observed among the entire population, a 5.9 mmHg reduction [95% confidence interval (CI): ?11.3, ?0.4] in systolic blood pressure was observed among women aged 40 or more years and a 4.6 mmHg reduction (95% CI: ?10.0, 0.8) was observed among obese women. Results from this study provide an indication that certain subgroups may be more likely to experience improvements in blood pressure following a cookstove intervention. 相似文献
114.
Exposure to household air pollution from biomass‐burning cookstoves and HbA1c and diabetic status among Honduran women 下载免费PDF全文
S. Rajkumar M. L. Clark B. N. Young M. L. Benka‐Coker A. M. Bachand R. D. Brook T. L. Nelson J. Volckens S. J. Reynolds C. L'Orange N. Good K. Koehler S. Africano A. B. Osorto Pinel J. L. Peel 《Indoor air》2018,28(5):768-776
Household air pollution from biomass cookstoves is estimated to be responsible for more than two and a half million premature deaths annually, primarily in low and middle‐income countries where cardiometabolic disorders, such as Type II Diabetes, are increasing. Growing evidence supports a link between ambient air pollution and diabetes, but evidence for household air pollution is limited. This cross‐sectional study of 142 women (72 with traditional stoves and 70 with cleaner‐burning Justa stoves) in rural Honduras evaluated the association of exposure to household air pollution (stove type, 24‐hour average kitchen and personal fine particulate matter [PM2.5] mass and black carbon) with glycated hemoglobin (HbA1c) levels and diabetic status based on HbA1c levels. The prevalence ratio (PR) per interquartile range increase in pollution concentration indicated higher prevalence of prediabetes/diabetes (vs normal HbA1c) for all pollutant measures (eg, PR per 84 μg/m3 increase in personal PM2.5, 1.49; 95% confidence interval [CI], 1.11‐2.01). Results for HbA1c as a continuous variable were generally in the hypothesized direction. These results provide some evidence linking household air pollution with the prevalence of prediabetes/diabetes, and, if confirmed, suggest that the global public health impact of household air pollution may be broader than currently estimated. 相似文献
115.
Some aspects of the passivation of mild steel in the presence of selected vapour phase corrosion inhibitors (VCIs) were considered. In particular their ability to vapourize was evaluated by sublimation tests and their role in the inhibition mechanism of mild steel was investigated by electrochemical methods such as open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) measurements. In the presence of some carboxylates, amines and azoles alone and as mixtures a protective layer can be formed on mild steel in neutral and alkaline solution. It was shown that the passivation mechanism strongly depends on the pH of the solution. In addition the influence of contaminants from industrial alkaline cleaning baths on the protective properties was analyzed. 相似文献
116.
Striegler A Koehler B Bendjus B Roellig M Kopycinska-Mueller M Meyendorf N 《Ultramicroscopy》2011,111(8):1405-1416
The miniaturization of micro- and nanoelectronic components requires new methods for the inspection of buried inner structures at the nanoscale. We used the atomic force acoustic microscopy technique (AFAM) to image subsurface defects. This technique combines high lateral resolution with the capability to determine local elastic properties of materials near the surface. As the structures buried near the surface change the effective tip-sample contact stiffness it is possible to detect them. For the verification of the detection capabilities of AFAM we fabricated well-defined buried void structures with different geometries and dimensions. Large, thin, plate like structures of silicon nitride with a local filling were our first test samples. Then, sets of nine small, square, thin plates with thicknesses increasing stepwise from 30 to 270 nm were etched in a thinned silicon wafer. The last two samples contained wedge structures of widths varying between 1.6 and 10 μm. Our results showed that it was possible to detect buried void structures at depths between 180 and 900 nm. We also observed that the depths at which the buried defects can be detected by the use of the AFAM method depend on the defect dimensions and geometry, and on the mismatch in the elastic properties of the sample and the defects. The experimental results obtained for the groups of small, thin plates were verified by quantitative analysis via finite element method (FEM) simulations. 相似文献
117.
PP Urban J Schlegel J Ellrich J Koehler HC Hopf 《Canadian Metallurgical Quarterly》1996,243(2):171-174
In children with steroid-resistant nephrotic syndrome (SRNS) hyperlipidaemia may in the long term be associated with progressive renal insufficiency and increased risk of coronary heart disease. We have assessed the efficacy and tolerability of diet prior to and in combination with a hydroxymethylglutaryl CoA reductase inhibitor, simvastatin, in seven children with SRNS with a mean age of 8 years (range 1.8-16.3 years). Dietary advice to maintain adequate energy and protein intakes with reduced saturated fat and cholesterol intake had little impact on lipid levels pre treatment (mean reduction in cholesterol 1 mmol/l, triglyceride 1.1 mmol/l) but was maintained throughout the study duration. The mean cholesterol and triglyceride concentrations pre treatment were 12.1 +/- 2 (SEM) mmol/l and 8 +/- 2.1 (SEM) mmol/l, respectively. On a median simvastatin dose of 10 mg/day (range 5-40 mg) there was a 41% reduction in cholesterol to 6.6 +/- 0.77 (SEM) mmol/l and a 44% reduction in triglyceride to 3.9 +/- 1.38 (SEM) mmol/l at 6 months which was sustained at 12 months in five patients. The drug was well tolerated with no clinical side effects being noted. Over 6 months the mean plasma albumin concentrations increased from 18.2 +/- 1.26 (SEM) g/l to 23 +/- 2.51 (SEM) g/l, accounted for by three patients (1 complete remission, 1 partial remission, 1 end-stage renal failure). Plasma creatinine concentrations remained stable in five patients with two having progressive chronic renal failure. Growth parameters for both weight and height were maintained. Simvastatin has a beneficial effect on abnormal lipid levels in SRNS but the effectiveness of long-term therapy needs to be evaluated. 相似文献
118.
Zhu Y. Comaniciu D. Pellkofer M. Koehler T. 《Intelligent Transportation Systems, IEEE Transactions on》2006,7(4):401-414
Early detection of overtaking vehicles is an important task for vision-based driver assistance systems. Techniques utilizing image motion are likely to suffer from spurious image structures caused by shadows and illumination changes, let alone the aperture problem. To achieve reliable detection of overtaking vehicles, the authors have developed a robust detection method, which integrates dynamic scene modeling, hypothesis testing, and robust information fusion. A robust fusion algorithm, based on variable bandwidth density fusion and multiscale mean shift, is introduced to obtain reliable motion estimation against various image noise. To further reduce detection error, the authors model the dynamics of road scenes and exploit useful constraints induced by the temporal coherence in vehicle overtaking. The proposed solution is integrated into a monocular vision system onboard for obstacle detection. Test results have shown superior performance achieved by the new method 相似文献
119.
Based on the results of a technology assessment study we show that pervasive computing could amplify already existing problems related to the environment, human health, and society. Power consumption for digital networks, e-waste streams, and exposure to nonionizing radiation may all increase. Furthermore, social sustainability could be threatened by the technology if it is applied in a way that restricts consumers' privacy and freedom of choice. We refer to the precautionary principle as an analytical framework for discussing the opportunities and risks of pervasive computing for sustainable development. 相似文献
120.
Yen‐Chu Lin Dr. Jan A. Hiss Dr. Petra Schneider Peter Thelesklaf Yi Fan Lim Max Pillong Dr. Fabian M. Koehler Prof. Dr. Petra S. Dittrich Prof. Dr. Cornelia Halin Prof. Dr. Silja Wessler Prof. Dr. Gisbert Schneider 《Chembiochem : a European journal of chemical biology》2014,15(15):2225-2231
Antimicrobial peptides (AMPs) show remarkable selectivity toward lipid membranes and possess promising antibiotic potential. Their modes of action are diverse and not fully understood, and innovative peptide design strategies are needed to generate AMPs with improved properties. We present a de novo peptide design approach that resulted in new AMPs possessing low‐nanomolar membranolytic activities. Thermal analysis revealed an entropy‐driven mechanism of action. The study demonstrates sustained potential of advanced computational methods for designing peptides with the desired activity. 相似文献