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1.
This paper describes the creep‐fatigue life of Sn–8Zn–3Bi under push–pull loading. Creep‐fatigue tests were carried out using Sn–8Zn–3Bi specimens in fast–fast, fast–slow, slow–fast, slow–slow and hold–time strain waveforms. Creep‐fatigue lives in the slow–slow and hold‐time waveforms showed a small reduction from the fast–fast lives but those in the slow–fast and fast–slow waveforms showed a significant reduction from the fast–fast lives. Conventional creep‐fatigue life prediction methods were applied to the experimental data and the applicability of the methods was discussed. Creep‐fatigue characteristics of Sn–8Zn–3Bi were compared with those of Sn–3.5Ag and Sn–37Pb.  相似文献   
2.
The effects of freeze-drying, hot air, and vacuum far infrared-drying on caucas (Allium victorialis L.) flavor was studied. The GC and GC-MS characterization of volatiles from dried caucas powders revealed the main flavor components; disulfides and trisulfides, as well as the antithrombotic substances; vinyldithiins, remained in all products. Vi-nyldithiins were isolated and subsequently confirmed by IR, NMR and Mass Spectrometry. Rehydration of the dried powders increased measurable volatile compounds, which were produced enzymatically. Increased-storage time decreased measurable volatiles in freeze-dried and hot air-dried caucas powders while the volatile profile remained unchanged.  相似文献   
3.
Extraction of metal ions from the aqueous-organic solution containing dimethyl formamide(DMF), dimethyl sulfoxide(DMSO) and acetonitrile(AN) was investigated by using di-2-ethylhexyl-phosphoric acid(D2EHPA) as an extractant. The organic phase was a binary solution of D2EHPA and n-hexane, or D2EHPA and toluene, while the polar phase was a three component solution of metal salt, non-aqueous solvent and water. The extracted metal ions were Cr(III), Fe(III), Al, Cu, Ni, Co(II), Mg and Ag.

The extraction behaviors may be explained by the solvation ability of non-aqueous solvents, the decrease in distribution of the extractant and extract into the organic phase, and the interaction between the extractant and non-aqueous solvents due to the dissolution of non-aqueous solvents in the organic phase.  相似文献   
4.
ABSTRACT

This paper summarizes the main results of our study carried out under the priority-area research “Energy Conversion and Utilization with High Efficiency” supported by the grant-in-aid of scientific research from the Ministry of Education, Science and Culture of Japan. In the research we focused on applications of solar energy utilization for industrial drying systems. In this paper a new concept of a closed drying system with superheated steam provided from a temperature boosting type heat pump (absorption type heat transformer) was proposed. The heat transformer is driven directly by heat from a solar collector. The performance for different three drying periods and a number of factors affecting it were predicted by a computer simulation. Furthermore the heat and mass transfer characteristics of water evaporation into superheated steam stream by radiative and convective heating were indicated experimentally. It was concluded that the system would be useful for industries where high temperature (over 100°C) drying is required.  相似文献   
5.
Abstract

The systems Ca(II)-As(III)-H2O and Ca(II)-As(V)-H2O were studied by equilibrating mixtures of calcium oxide and arsenious or arsenic acid solution at 25°C for one month. Where the pH of the final solution was likely to be greater than 8, care was taken to exclude atmospheric carbon dioxide. Chemical analysis of the final solid phases and the associated solution from each experiment for calcium and arsenic, together with X-ray diffraction analysis of the solids and an inspection of graphed relationships, indicated the existence of the compounds Ca(AsO2)2 and CaAsO2OH 1/2H2O in the system Ca(II)-As(III)-H2O; and Ca(H2AsO4)2, CaHAsO4 H2O, Ca3(AsO4)2 4H20 and Ca2AsO4OH 2H2O in the system Ca(II)-As(V)-H2O. The solubility and stability regions for these compounds were assessed as a function of pH, and solubility constants and conditional free energies of formation for each compound calculated from the solubility data obtained.

A brief historical review of literature in which calcium arsenites and calcium arsenates have been reported is included in this paper.  相似文献   
6.
7.
This paper summarizes the main results of our study carried out under the priority-area research “Energy Conversion and Utilization with High Efficiency” supported by the grant-in-aid of scientific research from the Ministry of Education, Science and Culture of Japan. In the research we focused on applications of solar energy utilization for industrial drying systems. In this paper a new concept of a closed drying system with superheated steam provided from a temperature boosting type heat pump (absorption type heat transformer) was proposed. The heat transformer is driven directly by heat from a solar collector. The performance for different three drying periods and a number of factors affecting it were predicted by a computer simulation. Furthermore the heat and mass transfer characteristics of water evaporation into superheated steam stream by radiative and convective heating were indicated experimentally. It was concluded that the system would be useful for industries where high temperature (over 100°C) drying is required.  相似文献   
8.
Paratropomyosin is a minor myofibrillar protein which in freshly prepared myofibrils is exclusively localized at the A-I junction region of sarcomeres. We investigated the ultrastructural localization of paratropomyosin in intact and postrigor myofibrils by immunoelectron microscopy. Paratropomyosin was localized as two distinct stripes at the A-I junction in intact myofibrils. It also was localized at the position corresponding to the original A-I junction in thick filament-free myofibrils (I-Z-I brushes). However, following postmortem storage, paratropomyosin was found broadly distributed in thin filaments of myofibrils.  相似文献   
9.
A S45C carbon steel has been solidified under different electromagnetic conditions to investigate the effect of the electromagnetic force imposition and its imposing period on the solidified structure in this study.For excitation of the electromagnetic force,a static magnetic field and a direct electric current were simultaneously imposed on a sample under a certain period of the solidification.After the solidification,the microstructures were observed and compared each other.As the results,microstructure of the S45C steel under the simultaneous imposition of a static magnetic field of 1T and a direct electric current of 20A in the latter stage of its solidification was dendritic while it was globular if the electromagnetic force was imposed during the whole solidification period.  相似文献   
10.
Volatile sulfur compounds of malt whiskies were analyzed using a gas chromatograph equipped with a flame photometric detector by direct injection and solvent extraction methods. Sulfur compounds identified by coupled gas chromatography-mass spectrometry and by matching GC retention times were dimethyl sulfide, dimethyl disulfide, dimethyl trisulfide, 3-(methylthio)propanal, 3-(methylthio)propanol, 3-(methylthio)propyl acetate, ethyl 3-(methylthio)-propanoate, dihydro-2-methyl-3(2H)-thiophenone, 2-thiophene-carboxyaldehyde, 5-methyl-2-thiophenecarboxaldehyde, benzothiophene and benzothiazole. Quantitative changes in these volatile sulfur compounds were studied by analyzing 48 aged and unaged malt whiskies by these methods. Dimethyl sulfide, 3-(methylthio)propyl acetate, dihydro-2-methyl-3(2H)-thiophenone and ethyl 3-(methylthio)propanoate decreased rapidly during aging and disappeared within three years. Dimethyl disulfide decreased gradually during aging. Dimethyl disulfide proved to be formed during distillation by the action of copper.  相似文献   
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