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71.
Cling films and single-use plastics are difficult to recycle and cause major environmental pollution, leading to an increase in microplastics in nature. To overcome this issue, biodegradable films are being explored more extensively. Seaweed is gaining prominence in the food packaging sector since it is beneficial in all aspects. Two fractions of Indian brown seaweed Sargassum wightii, biopolymer (sulfated polysaccharide [SP]) as base material and nanofillers (cellulose nanocrystals [CNC]) as reinforced filler are employed to develop a sustainable cling film for food packaging. This cellulose filler can be isolated from solid seaweed biomass after the polysaccharide extraction and converted into nanoform using the response surfaces method (RSM) to maximize the yield of CNC. The objective of this research is to construct seaweed-based biodegradable nanocomposite films and to examine their improved properties. It exhibited a gradual decrease in water absorption and water vapor permeability (WVP), along with better wettability, mechanical, and antioxidant properties, and thermal analysis compared with the control SP film. The degradation rates of the films were analyzed using the soil-burial method. According to the results obtained, it is suggested that CNC can be utilized as a functional filler to improve the qualities of seaweed-based cling films.  相似文献   
72.
The quality aspects of CTC (crush, tear and curl) black teas were examined against different sources of potassium fertiliser. Potassium supplied as muriate of potash (MOP) improved the liquor components such as theaflavin (TF), thearubigin (TR) and TF/TR ratio at higher levels. The same effect was noticed at lower level itself when the source of K was changed to sulfate of potash (SOP). Termination of K application reduced the TF/TR ratio drastically. The entity responsible for strength, body and colour of tea brew, namely highly polymerised substances, attained its optimum proportion at an NK ratio of 1:0.21 using SOP. Generally, there was a good response from SOP‐treated blocks to caffeine. The flavour index was a maximum at a 1:0.42 NK ratio, using SOP. A slight peak and trough were observed in the case of crude fibre content and water extract over control and MOP‐treated blocks. The leaf K content was negatively correlated with CFC content of made tea. An antagonism was observed between leaf K and Mg. Copyright © 2005 Society of Chemical Industry  相似文献   
73.
An experiment was conducted to evaluate the effect of dipping in pomegranate fruit juice phenolics (PFJP) solution on the shelf life of chicken meat held under refrigerated storage at 4°C. Breast muscle obtained from spent hens was dipped (1:2w/v; muscle: liquid) in sterile water or in sterile water with 0.02% (v/v) PFJP, packed, stored at 4°C for 28 days and samples were analyzed on 2 days of intervals. Thiobarbituric acid reactive substance values were lower in samples treated with PFJP. Total sulfhydryl and protein bound sulfhydryl content values were higher in samples treated with PFJP. Microbial quality evaluation showed that aerobic and psychrotrophic counts were higher in samples treated without PFJP. Sensory evaluation revealed that acceptability level of samples treated without PFJP decreased on 12th day of storage. It is concluded that spent hen breast meat samples dipped in 0.02% PFJP reduced protein oxidation and inhibited microbial growth and sensorily acceptable up to 12 days of refrigerated storage at 4°C.  相似文献   
74.
These days with the expanded fame of cloud computing, the interest for cloud-based collaborative editing service is rising. The encryption method is utilized to ensure and secure the data, during the collaborative editing process. In the encryption process, the cloud requires more time to work the collaborative editing. This paper proposes an efficient scheme for reducing the encryption burden over the cooperative users, as the possibilities of cooperative users read and write data by means of any gadget. In the proposed scheme, the encrypted file sent by the data owner is split into smaller segments and stored in the cloud by the cloud service provider (CSP) along with specific tags. Once the cooperative user receives and decrypts the file from the CSP, it modifies and encrypts only the modified segment and resends to the CSP. The CSP after verifying the signature replace the original file segment in the cloud with the modified segment based on the tag information. The scheme that is put forward is performed based on the modified ciphertext-policy hierarchical attribute–based encryption, and the security process is done based on the attribute-based signature schemes. This work employs a proficient attribute updating method to accomplish the dynamic change of users' attributes, consisting granting new attributes, revoking previous attributes, and regranting formerly revoked attributes. A writer's attributes and keys have been revoked, and the stale information cannot be written.  相似文献   
75.
Collagen microspheres usually have particle size lesser than 200 µm, which are characteristically free-flowing powders of protein. They can overcome some of the conventional therapy problems and enhance therapeutic efficacy due to their biocompatible and biodegradable nature. Collagen microspheres were prepared using the fish Lates calcarifer scale collagen and were loaded with Bixa orellana plant extract. The Bixa orellana plant extract-loaded collagen microsphere was characterized for its physico-chemical properties using Fourier-transform infrared, Raman spectra, X-ray diffraction, scanning electron microscopy, and particle size analysis, and in vitro plant extract release. This plant extract showed good antimicrobial property against Staphylococcus aureus and Escherichia coli. The in vitro anticancer activity of the prepared material was carried out using MCF-7 cell lines which showed 83.46 % of cell death at 1000 µg/well. Anticancer effect of the prepared material can be enhanced by increasing the concentration of plant extract in the composite.  相似文献   
76.
77.
This paper deals with the performance tests of a PRB (porous radiant burner) used for LPG (liquefied petroleum gas) domestic cooking stoves. The burner consists of a two-layer porous media. The combustion zone is made up of silicon carbide, and alumina balls forms the preheating zone. For a given burner diameter, the performances of the burner, in terms of thermal efficiency and emission characteristics, are analysed for different equivalence ratios and thermal loads (wattages). The water boiling test as prescribed in the BIS (Bureau of Indian Standard): 4246:2002 was used to calculate the thermal efficiency of both the conventional LPG cooking stoves and the PRB. The maximum thermal efficiency of the LPG cooking stoves with a PRB was found to be 68% which is 3% higher than that of the maximum thermal efficiency of the conventional domestic LPG cooking stoves. Unlike the conventional LPG stoves, for which the CO and NOX emissions were found in the ranges 400–1050 mg/m3 and 162–216 mg/m3, respectively, for the one with PRB, the same were in the ranges of 25–350 mg/m3 and 12–25 mg/m3. The axial temperature distribution in the burner showed that the reaction zone was close to the interface of the two zones and at a higher thermal load, it shifted towards the downstream. The surface temperature of the PRB was found to be uniform.  相似文献   
78.
Metal hydride based heating and cooling systems: A review   总被引:1,自引:0,他引:1  
Dry (solid) sorption systems are attractive competitors to wet (liquid) sorption systems in providing useful cold and/or useful heat. Among the dry sorption systems, those based on the absorption/desorption of hydrogen in/from metal alloys reveal advantageous features, and this has stirred up the interest of researchers already since the 1970s. In recent years, many attempts have been made to develop metal hydride based heating and cooling systems. Of special interest was and is the possibility to utilize low temperature heat (waste heat, solar heat) to drive those systems. Major applications are seen in air-conditioning and heat supply for buildings and in air-conditioning of automobiles. In this paper, the research and development work on metal hydride based heating and cooling systems is reviewed which has been published in the last three decades. Emphasis is given primarily to cooling/air-conditioning. The objectives are to provide the fundamental understanding of metal hydride based heating and cooling systems and to give useful guidelines regarding various design parameters. The operation principles of various types of systems are explained and the importance of the metal hydride reaction bed heat and mass transfer characteristics is stressed. Possible ways for improving the coefficient of performance and specific cooling capacity are discussed. Besides a brief characterization of many experimental and theoretical investigations, the worldwide status of the development of metal hydride based heating and cooling systems is summarized in a tabular form.  相似文献   
79.
Noise pollution is an ever increasing problem in the world because of the industrial revolution. Recently, researchers have begun investigating natural fiber composites as potential materials for the manufacture of sound absorption structures. In this work, flax/low melting point polyester needle punched nonwoven fabrics were manufactured and characterized for sound and thermal insulation applications. Nonwovens were developed by blending flax fibers with low melt PET at three blend ratios (10%, 20%, and 30%) with 7 mm and 10 mm needle penetration depth. The test results showed that there was a decrease in thermal resistance value with increase in low melt PET % and needle penetration depth. The developed nonwovens had better sound insulation value at medium and high frequency. There was no significant change in sound insulation value with increase in low melt PET %.  相似文献   
80.
Over two decades, research in the field of metal hydride based thermal machines has gained immense attention by the researchers of different fields. Because of its capability to store large volume of hydrogen per unit mass at near ambient condition, its utilization has been spread in numerous applications such as energy storage and other biological, chemical, aerospace and nuclear applications. Though there have been several review reports published on metal hydride based hydrogen storage, but the present work is focused on the thermal management issues and worldwide developmental status of various metal hydride based thermal machines such as thermal energy storage, heat upgradation, heat pump, cooling system, and hydrogen purification and compression. With a brief discussion about the basic understanding of metal hydride alloy formation, this paper also covers screening of metal hydride alloys, design considerations and evolution of different reactor geometries for various metal hydride based thermal management systems. The review also addresses the benefit of coupling of a metal hydride based hydrogen energy system with a conventional thermal system in order to a produce hybrid system with much higher performance and almost zero environmental pollution.  相似文献   
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