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31.
Ajit Sadana 《Chemical Engineering Communications》1987,49(4):291-300
During the forming of glass articles by a variety of different processes, it is important to be able to accurately measure the temperature of the glass. Also, to be practical for production applications, the temperature measuring technique must not interfere with the process or disturb the product. Only infrared radiation pyrometry is capable of meeting these requirements.
Narrow-band radiation pyrometers are non-contacting sensors that (depending on the operating wavelength) either measure the surface temperature or some weighted average of the surface and internal temperatures of semi-transparent glass objects without significantly affecting the product or its heat exchange with the environment. When attempting pyrometer temperature measurements on glass, it must be recognized that the incident radiation originates not only from the surface, but also from the interior which may be at a different temperature. However, a knowledge of the directional spectral volume emissive power of the glass object can be used to determine a "best" operating wavelength for the desired results and/or to help interpret indicated temperature measurements.
A sophisticated mathematical model of coupled radiation and conduction heat transfer in glass has been formulated to calculate the apparent temperature indicated by a hypothetical narrow-band infrared pyrometer receiving radiation emitted by glass plates of specified thickness and non-uniform temperature distribution. These results are presented for a wide range of operating wavelengths, covering the three distinct regions of the transmission spectrum of a typical soda-lime-silica glass. 相似文献
Narrow-band radiation pyrometers are non-contacting sensors that (depending on the operating wavelength) either measure the surface temperature or some weighted average of the surface and internal temperatures of semi-transparent glass objects without significantly affecting the product or its heat exchange with the environment. When attempting pyrometer temperature measurements on glass, it must be recognized that the incident radiation originates not only from the surface, but also from the interior which may be at a different temperature. However, a knowledge of the directional spectral volume emissive power of the glass object can be used to determine a "best" operating wavelength for the desired results and/or to help interpret indicated temperature measurements.
A sophisticated mathematical model of coupled radiation and conduction heat transfer in glass has been formulated to calculate the apparent temperature indicated by a hypothetical narrow-band infrared pyrometer receiving radiation emitted by glass plates of specified thickness and non-uniform temperature distribution. These results are presented for a wide range of operating wavelengths, covering the three distinct regions of the transmission spectrum of a typical soda-lime-silica glass. 相似文献
32.
The use of multiple coordinated views (MCV) in data visualization provides analytic power because it allows a person to explore data under a variety of different perspectives. Since this design pattern utilizes multiple visualizations and requires coordinated interactions across the views, a clever use of screen space is vital and many synchronized interface operations must be provided. Bringing this design pattern to tablet computers is challenging due to their small display size and the absence of keyboard and mouse input. In this article, we explain important design considerations for MCV visualization on tablets and describe a prototype MCV visualization system we have built for the iPad. The design is based on the principles of maximizing screen space for data presentation, promoting consistent interactions across visualizations, and minimizing occlusion from a person's hands. 相似文献
33.
Field experiments were conducted in zinc-deficient sodic soil to study the effect of levels and methods of zinc fertilization on yield, concentration and uptake of zinc by rice. Zinc was incorporated in the soil at the rate of 0, 5.6, 11.2 and 22.4 kg Zn per ha as zinc sulfate; sprayed on the plants at 1% and 2% zinc sulfate solution; and roots of rice seedlings were dipped in 2% and 4% ZnO suspensions in water. Grain yield, zinc content and its uptake increased in all the experiments up to 22.4 kg Zn per ha. Soil applied zinc was significantly correlated with yield of rice (r = 0.80**) and zinc uptake (r = 0.89**). Zinc content in 45-day old plants gave a significantly higher correlation with grain yield (r = 0.84**) than the zinc content of rice straw and grain at maturity. Roots of rice seedlings dipped in 2% or 4% zinc oxide suspension in water were not only comparable with soil application of Zn at 5.6 and 11.2 kg Zn per ha, but also proved to be more economical for sodic soils showing moderate zinc deficiency. 相似文献
34.
Isolation and chemical composition of surface-active material from human lung lavage 总被引:1,自引:0,他引:1
Surface-active material (SF) was isolated from human lung lavage fluid collected at autopsy employing differential and sucrose
density gradient centrifugation. The isolated material showed well-defined electron microscopic structure, consisting of clearly
preserved, closely packed vesicles with limiting membranes and inclusion bodies. It showed a very high degree of alkaline
phosphatase specific activity and was devoid of other subcellular contaminants. The isolated material also showed a high phospholipid/protein
ratio and increasing surface activity when monitored at different stages of purification. It contained 68.5% phosphatidylcholine,
11.5% phosphatidylglycerol and relatively smaller amounts of phosphatidylethanolamine and other individual phospholipid (PL)
classes. In addition, cholesterol, unesterified fatty acids, triacylglycerols and other neutral lipids were found. Saturated
fatty acids, particularly palmitic acid (16∶0), predominated in the major PL fractions. However, various fatty acids of which
oleic acid (18∶1) constituted a large proportion also are present. Chemical analysis of the material showed that besides lipids
and proteins, nucleic acids, sialic acid, hexose, amino sugars, nitrogen and phosphorus were present. The delipidated material
showed the presence of three to four proteins as characterized by sodium dodecylsulfate (SDS)-polyacrylamide gel electrophoresis,
and gel permeation chromatography on Sephadex G-200 resolved two well-separated peaks. The first fraction contained serum-associated
68 kDa protein, while the second fraction had two apoproteins with molecular weights of 34 kDa and 10 kDa. These two proteins
were associated with the SF and they, as well as the whole surface-active material, strongly reacted with the antibody directed
against the whole SF in a double-diffusion immunoprecipitation assay. The first Sephadex fraction containing a 68 kDa protein
did not produce any precipitation line when reacted against antisera. 相似文献
35.
Methods and rates of application of Mn and its critical levels for wheat following rice on coarse textured soils 总被引:7,自引:0,他引:7
Two field experiments were conducted on Mn-deficient soils to evaluate the efficiency of rates, methods and time of MnSO4.H2 O application for wheat. Manganese sulphate was broadcast and mixed in soils at the rate of 5 to 50kg Mn ha–1 before seeding and 10 to 40 kg Mn ha–1 as top dress at 28 days — just before first irrigation. Three sprays of 1% MnSO4·H2O unneutralised solutions were applied, the first at 26 days — 2 days before first irrigation and the others afterward at weekly intervals. Both the methods caused a significant and marked increase in grain yield. Three foliar sprays were as effective as soil applications of 20 to 40 Kg Mn ha–1 before seeding. The difference in grain yield resulting from soil applications of Mn before seeding and applications at the first irrigation was not significant. The DTPA-Mn status of 20 fields, selected on the basis of varying degree of Mn deficiency, was related to grain yield (r = 0.77**). Also grain yield of all the experiments had a significant correlation with Mn content of grain (r = 0.55** to 0.82**) and straw (r = 0.77** to 0.82**). The critical limits calculated by statistical method were 1.25, 2.18 and 3.5 mg Mn kg–1 soil for severe deficiency, deficiency and latent deficiency respectively for wheat. 相似文献
36.
R. N. Gedye Y. N. Sadana A. C. E. Edmonds M. L. Langlois 《Journal of Applied Electrochemistry》1987,17(4):731-736
Electrolysis of nitration waste sulphuric acid, from the manufacture of trinitrotoluene, results in the formation of a dark solution in which the concentration of aromatics is reduced to much lower levels. The resulting acid can be decolourized by oxidation with H2O2 or by anodic oxidation in the cell. The H2O2-treated electrolysed acid has a nitroaromatic content of 107 p.p.m. and a total carbon content of 278 p.p.m., corresponding to a reduction of 98.7% and 90.3%, respectively. The dark intermediate product appears to result from the anodic oxidation of amines which are initially produced at the cathode, and is destroyed by further anodic oxidation on prolonged electrolysis. 相似文献
37.
Manabu ShinrikiKeith Chung Satoshi HasakaPaul Brabant Hong HeThomas N. Adam Devendra Sadana 《Thin solid films》2012,520(8):3190-3194
Gas phase particle formation and elimination in silicon epitaxial layers grown on Si (100) substrates using reduced pressure chemical vapor deposition at low temperatures (< 600 °C) are investigated. High-order silane precursors (SinH2n + 2; n = 3, n > 3) are useful for high growth rate epitaxy at low temperature. However, particulates are observed on the surface of the epitaxial layers grown with high-order silanes. These particulates are attributed to gas phase particles. As atomically smooth epitaxial films are desired, the elimination of gas phase particles is required. Cyclical deposition and etch process and/or low pressure deposition enables atomically smooth SiCP epitaxial films with a high-order silane. 相似文献
38.
在某些科技产品的使用过程中,美国女性的主导权超过男人,比如观看电视节目、DVR使用、浏览社会类媒体网站,甚至是打游戏。这个调查结果是由Solution Research Group发布的一个新的、关于“女性和数字生活方式”报告发布的。 相似文献
39.
40.
BACKGROUND: Nuclear deoxyribonucleic acid (DNA) content is a prognostic factor in several tumors, and decisions regarding treatment have been made using this parameter. Nevertheless, there is no agreement in head and neck cancer. The purpose of the present study was to ascertain whether tumor DNA content correlated with prognosis in cases of primary squamous cell carcinoma (SCC) of the oral cavity and tongue base. METHODS: A retrospective study of formalin-fixed, paraffin-embedded tissue from patients with histologically confirmed SCC of the oral cavity and tongue base was performed using flow cytometry. Tumor DNA content was studied in 109 sets of specimens from previously untreated patients. All of them underwent surgical resection at the University "Hospital de La Princesa" between 1982 and 1992. Clinical parameters (age, sex, site of primary tumor, clinical stage, adjuvant therapy received, and disease-free and overall survival) and histologic parameters (histopathologic stage, tumor differentiation, type of inflammatory infiltration, presence of perineural invasion) were recorded in all cases. An exhaustive statistical analysis was applied. RESULTS: Only the histograms of 93 patients were adequate for consideration. In flow cytometric analysis, DNA aneuploidy was observed in 51 tumors (55%). The proportion of aneuploid tumors was significantly higher in advanced-stage carcinomas (p < .05), tumors with perineural invasion (p < .05) and in men (p < .05). In the 24 patients with lymph node metastasis, the incidence of aneuploidy was 82% (19 of 24) (p < .05). The rate of metastasis and aneuploidy increased as the degree of differentiation decreased (p < .05 for both). Patients with aneuploid carcinomas in both early and advanced stages had shorter relapse-free and overall survival periods than did the patients with diploid tumors (p < .001 for both). A Cox regression analysis demonstrated that ploidy was the single most important prognostic factor in determining relapse and death (p < .001 for both). CONCLUSIONS: The results indicate that tumor DNA analysis by flow cytometry appears to be useful as a supplement to clinical and histologic evaluation in predicting the tendency of SCC of the oral cavity and tongue base to metastasize to regional lymph nodes and to predict the outcome of the disease. 相似文献