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排序方式: 共有377条查询结果,搜索用时 0 毫秒
1.
LR Reminick PT Finger R Ritch S Weiss H Ishikawa 《Canadian Metallurgical Quarterly》1998,69(9):575-582
BACKGROUND: High-frequency ultrasound biomicroscopy has allowed eye care specialists to evaluate posterior extension of anterior segment tumors. This article evaluates the role of ultrasound biomicroscopy for the diagnosis and management of anterior segment tumors. METHODS: Fourteen patients with anterior segment tumors were selected for evaluation. Each patient underwent a complete clinical examination followed by slit-lamp photography and ultrasound biomicroscopy. RESULTS: Unlike standard ultrasonography of anterior segment tumors, high-frequency ultrasound biomicroscopy allowed quantitative measurements of tumor size, extension within and posterior to the iris, as well as differentiation of solid and cystic lesions. These characteristics were used to differentially diagnose anterior segment tumors and document the response of iridociliary body melanomas to radiotherapy. CONCLUSIONS: This study demonstrates how ultrasound biomicroscopy has become an effective and necessary procedure, used for both the diagnosis and management of anterior segment tumors. 相似文献
2.
J. C. Illman B. M. Finger W. T. Shebs T. B. Albin 《Journal of the American Oil Chemists' Society》1970,47(10):379-383
The effects of single and multiple washing and of resoiling-rewashing of cotton and synthetic fabrics have been studied in
Tergotometer tests at various levels of temperature, detergent concentration and water hardness. The soiling mixture consisted
of a seven component sebum tagged with tritium and carbon-14; in some tests gammaray emitting Kaolinite clay was also used.
Linear primary alcohol ethoxylate (LAEO) and linear alkylbenzene sulfonate (LAS) were used for surfactant type comparisons.
In single wash tests in both hot and cold water, LAEO was generally more effective than LAS in removing sebum. This was particularly
noticeable at low product concentration where insufficient sodium tripolyphosphate was present to sequester the water hardness.
A 1/1 blend of the two surfactants approached LAEO in performance. The nonpolar sebum fraction was more readily removed from
Dacron or nylon in cold water; otherwise, detergency was generally better at high temperatures. In rewash tests, using labeled
lube oil, cholesterol and clay, a progressive increase in soil removal was found during five wash cycles. The nonpolar lube
oil component was the most difficult to remove from permanent press Dacron-cotton (PP), but was more readily removed from
cotton. The more polar cholesterol and especially the clay were more easily removed from PP. LAEO gave better detergency both
hot and cold than LAS, especially in hard water. On cotton swatches resoiled with sebum after each wash the residual sebum
content was still increasing after five cycles. With PP in soft water, a steady state was reached after three to five cycles.
Soil buildup was greater as hardness increased and as wash temperature and active matter concentration decreased, and was
generally greater on cotton than on PP. LAEO allowed appreciably less soil buildup than did LAS especially at low concentration
in hard water, indicating a reduced requirement for sodium tripolyphosphate.
Presented before the AOCS Meeting, New Orleans, April 1970. 相似文献
3.
The effects of long-chain branching and of temperature on the melt elasticity in shear of polyethylene were investigated using die swell measurements and relating them to recoverable shear strain, normal stress, and shear modulus. Die swell measurements, as a function of shear rate, were obtained for high- and low-density polyethylenes at temperatures ranging from 130° to 225°C. The samples were characterized by GPC and intrinsic viscosity for molecular weight distributions and degrees of long-chain branching. The importance of annealing the extrudates at temperatures above the polymer melting temperature to achieve equilibrium, or strain-free, values of die swell was demonstrated. The effect of long-chain branch was to decrease elastic deformation. At constant shear stress, the melt elasticity of both high- and low-density polyethylene was found to be essentially independent of temperature. Thus, at constant shear rate, elastic deformation decreased with increasing temperature, and it was demonstrated that this decrease could be quantitatively defined in terms of previously determined shear rate–temperature viscosity superposition shift factors. 相似文献
4.
5.
Conclusions An analysis has been made of data on structure formation processes in spinning viscose fibres and of the connection of the primary structure with the properties of the finished fibres and yarns.It has been shown that the attainment of high physicomechanical and operational properties of viscose fibres is possible by preventing premature crystallization of the cellulose in the freshly-spun gel-fibre.Retardation of the cellulose crystallization process in spinning viscose fibres is advisably effected as a result of reducing the activity of water in the precipitation bath.Translated from Khimicheskie Volokna, No. 1, pp. 8–13, January–February, 1986. 相似文献
6.
7.
Wolfgang Sümmermann Hans Rohleder und Friedhelm Korte 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1978,166(3):137-144
Zusammenfassung Im Rahmen eines koordinierten Forschungsprogramms des BMFT wurde eine orientierende Studie an möglichst repräsentativen Stichproben durchgeführt. Trotz relativ großer Streubreiten zeichnen sich die Bereiche der wichtigsten Lebensmittelgruppen deutlich voneinander ab mit Mittelwerten um 0,005 /g für fettarme pflanzliche Grundnahrungsmittel, um 0,05 /g für pflanzliche Nahrungsfette, um 0,3 /g für Milch-, Käse und Butterfette, um 0,15 /g für sonstige Nahrungsfette von Landtieren, um 0,03 /g für Hühnereier und um 10 /g für Fischfett. Wichtet man die Gehalte entsprechend der durchschnittlichen Diät in der BRD, so ergibt sich eine tägliche PCB-Aufnahme von rund 29 aus tierischen Fetten und rund 6 aus den übrigen Lebensmitteln. Die Gesamtaufnahme von ca. 35 g pro Tag und capita entspricht etwa dem Wert, der von der WHO als ADI-Wert für HCB (Hexachlorbenzol) in Aussicht genommen wurde.
Polychlorinated biphenyls (PCB) in foodThe situation in the Federal Republic of Germany
Summary In a coordinated research program of the Federal Ministry of Research and Technology (BMFT), a screening study was carried out with representative samples. In spite of rather large ranges of PCB concentrations, the most important food-stuffs show clearly defined clusters with mean values of approx. 0.005 /g in low fat food components of plant origin such as cereals or potatoes, approx. 0.05 /g in vegetable fats, approx. 0.3 /g in fat from milk, butter and cheese, approx. 0.15 gg/g in animal fat, approx. 0.03 in chicken eggs and approx. 10 /g in fish fat. Considering the mean diet in the FRG, a daily PCB intake of about 29 g from animal fat and of 6 from the other food-stuffs results. The total intake of about 35 g per day and capita is almost the same as the figure conditionally suggested by the WHO as the acceptable daily HCB (hexachlorobenzene) intake.相似文献
8.
Zilla Sinuany-Stern Nachum Finger Elias Kligler 《Computers, Environment and Urban Systems》1986,11(4)
This paper provides a model for finding the optimal thinning policy in a pine forest (Pinus halepensis) in Israel. The model simulates the growth of a pine forest stand for timber, under various thinning policies. The annual growth functions are estimated via polynomial regression analysis. The dependent variable is the timber volume of the stand and the explanatory variable is the mean growing space per tree over time. The observations were made over the life span of five experimental parcels in a pine forest in Israel. 相似文献
9.
Shibaprasad Sen Mridul Mitra Ankan Bhattacharyya Ram Sarkar Friedhelm Schwenker Kaushik Roy 《Neural Processing Letters》2019,50(3):2281-2304
Feature selection through optimization techniques provides an interesting approach to minimize computational time with enhanced prediction capability, and 相似文献
10.
Andrey Frolov Kimberly Miller Jeffrey T. Billheimer Tae-Hyeon Cho Friedhelm Schroeder 《Lipids》1997,32(11):1201-1209
Although it was recently recognized that sterol carrier protein-2 (SCP-2) interacts with fatty acids, little is known regarding the specificity of SCP-2 for long-chain fatty acids or branched-chain fatty-acid-like molecules. Likewise the location of the fatty-acid binding site within SCP-2 is unresolved. A fluorescent cis-parinaric acid displacement assay was used to show that SCP-2 optimally interacted with 14–22 carbon chain lipidic molecules: polyunsaturated fatty acids > monounsaturated, saturated > branched-chain isoprenoids > branched-chain phytol-derived fatty acids. In contrast, the other major fatty-acid binding protein in liver, fatty-acid binding protein (L-FABP), displayed a much narrower carbon chain preference in general: polyunsaturated fatty acids > branched-chain phytol-derived fatty acids > 14- and 16-carbon saturated > branched-chain isoprenoids. However, both SCP-2 and l-FABP displayed a very similar unsaturated fatty-acid specificity profile. The presence and location of the SCP-2 lipid binding site were investigated by fluorescence energy transfer. The distance between the SCP-2 Trp50 and bound cis-parinaric acid was determined to be 40 Å. Thus, the SCP-2 fatty-acid binding site appeared to be located on the opposite side of the SCP-2 Trp50. These findings not only contribute to our understanding of the SCP-2 ligand binding site but also provide evidence suggesting a potential role for SCP-2 and/or L-FABP in metabolism of branched-chain fatty acids and isoprenoids. 相似文献