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101.
A method of induction of multiple DNA-protein and protein-protein cross-links in chromatin of isolated nuclei has been developed. The cross-linking is brought about by mutual effect of fluorochrome ethidium bromide (EtBr) and irradiation with blue light. Electron microscopic analysis of nuclei isolated in solutions with various concentrations of divalent cations, stained with EtBr and irradiated with blue light, has demonstrated that the method leads to a selective stabilization of macromolecular complexes of chromatin against various treatments causing decompactization of native chromatin. Besides that, the stabilization of nucleoli and clusters of interchromatin granules takes place. On the other hand, the same treatment does not stabilize elementary chromatin fibers (about 30 nm thick), and the transition to the nucleosomal fiber occurs after extraction of histone H1 with 0.6 M NaCl. Electrophoretic analysis of proteins from control and irradiated nuclei shows the basic role of non-histone proteins in the stabilization. The data are discussed based on the assumption on the availability of some "intermediate" levels of chromatin compaction between 30 nm chromatin fiber and mitotic chromosome.  相似文献   
102.
The conversion of a Sr–Ti bimetallic methoxyethoxide precursor into SrTiO3 via hydrolysis and/or calcination was investigated. Hydrolysis with various water/metal molar ratios ( r H; r H= 0.5, 2, 4, 6, 8, 10) in tetrahydrofuran at reflux resulted in a decrease in the amount of the methoxyethoxyl groups, and the hydrolyzed products were soluble with r H≤ 2. At r H≥ 8, SrTiO3 was crystallized without calcination. Both the hydrolyzed and unhydrolyzed precursors ( r H= 0, 0.5, 2) were calcined in dry air at 550°–800°C. SrTiO3 was crystallized on calcination at ≥550°C from amorphous materials with a considerable loss of carbon, which was present as both chars and carbonate ions.  相似文献   
103.
In this paper, the exergy flow and exergy efficiency of a 3 kW proton-exchange-membrane fuel cell were investigated, and the regional characteristic of the distributed energy system was considered. In the environmental temperature range of 263–313 K, the difference in the total efficiency of the proposed system was 6%. On the other hand, the difference in the exergy total efficiency of the same temperature range was 30%. Moreover, as a result of examining how to improve the exergy efficiency of this system, certain improvement methods were proposed: (a) preheat the city-gas and air supplied to the system using exhaust heat and raise the combustion temperature; (b) preheat the water supplied to the system using exhaust heat; (c) change the catalyst material of each unit and reduce the amount of cooling of the reformed gas; and (d) examine the combined cycle power generation. The exergy efficiency, in the case of introducing the proposed system into individual homes in Sapporo, Tokyo, and Kagoshima, was evaluated. Consequently, when the system was introduced into a community with low outside air temperatures, exergy efficiency increased compared with communities with high outside air temperatures.  相似文献   
104.
The synthesis of functionalized fullerene‐C60 (C60) was performed using living anionic polymerization. The metalation of the benzylic hydrogen atom on toluene or p‐substituted toluene was conducted with the alkyllithium/amine system, and examined by living anionic polymerization of 1,3‐cyclohexadiene. The number of carbanions bonded onto C60 was estimated by the grafting reaction of living polymer onto C60. The tert‐butyllithium/N,N,N′,N′‐tetramethylethylenediamine system was an effective metalation reagent, and toluene‐, p‐xylene‐, 4‐methyltriphenylamine‐functionalized C60s having good solubility were successfully synthesized. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
105.
Gluten peptides are prepared using limited hydrolysis of wheat gluten, resulting in improved solubility and physico-chemical properties. In general, the hydrolysis is performed using a batch-wise process. In this study, we developed a bioreactor system that can continuously produce gluten peptides with foaming properties. Two kinds of acid protease, pepsin and rapidase, were immobilized on porous chitosan beads. The partial deamidation of gluten in advance increased initial velocity of hydrolysis by immobilizing protease and also worked to enhance foaming properties. A packed-bed reactor filled with immobilized protease was designed, and operating parameters were optimized. The optimized conditions were as follows: pH, 3.0; temperature, 40 °C; substrate concentration, 40 mg/ml; and space velocity, 2.0 h–1. Based on these results, a bench-scale reactor was manufactured to determine the stability of continuous operation. The half-life of the reactor was approximately 45 days, and both productivity and quality were stable and excellent.  相似文献   
106.
107.
This paper proposes a method to realize a 3D video system that can capture video data from multiple cameras, reconstruct 3D models, transmit 3D video streams via the network, and display them on remote PCs. All processes are done in real time. We represent a player with a simplified 3D model consisting of a single plane and a live video texture extracted from multiple cameras. This 3D model is simple enough to be transmitted via a network. A prototype system has been developed and tested at actual soccer stadiums. A 3D video of a typical soccer scene, which includes more than a dozen players, was processed at video rate and transmitted to remote PCs through the internet at 15–24 frames per second.  相似文献   
108.
Connection of a large number of the dispersed generators to distribution networks is not easy due to various technical considerations. Thus, we have been trying to devise a concept for future electrical distribution systems with many dispersed generators. In this work, it has been considered that each customer's load and each generator's active and reactive power should be controlled in order to stabilize and optimize the networks. Under this consideration, two control methods for future distribution systems are proposed, a cooperative control and an independent control. We have confirmed experimentally that the voltage regulation ability is higher with the cooperative control than with the independent control, especially in cases of an eccentric load profile in a feeder and a heavy load. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 154(4): 16–23, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20246  相似文献   
109.
Biaxially oriented polypropylene films are widely used for food packaging and industrial films. Recently, machine speed has been increasing in order to obtain higher production rate, and film thickness has become thinner to reduce the environmental load. The customers' requirements for better production ability and thinner films have been becoming more demanding, but their demands are not always met because of lack of film stretchability in the final product. To meet the demands, research on stretchability has been conducted with the goal of finding the optimum polypropylene molecular structure for developing a new product by analyzing stretching force–strain data using a table tenter, which was thought to be the parameter of stretchability. It was found that low crystallinity and wide molecular weight distribution were effective in improving the stretchability from the table tenter test. By running the test with a sequential and biaxially oriented stretching machine, it was verified that samples produced by the above designed polymer indicated good thickness uniformity, which was considered to be the barometer of stretchability. Furthermore, it was concluded that analyzing the stretching force–strain data obtained from a table tenter is a good method to predict machine speed and film thickness. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers  相似文献   
110.
SnO2 single crystals have short prismatic habits bounded by well-developed {110} and {111} faces in a pure SnO2–Cu2O flux system. When trivalent cations are added to the system, the habits drastically change to needle, acicular, or whisker forms with large aspect ratios. The addition of trivalent cations also greatly increases the nucleation rate and drastically decreases the crystal size. SEM observations and EPMA investigations reveal that the flat {111} faces transform to rounded or rough { hkl } faces by the addition of trivalent cations. This roughening transition of {111} faces, keeping {110} faces unchanged, is the cause of drastic habit modification that is attributed to the breaking of the periodic bond chain in {111} faces by impurity cations.  相似文献   
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