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101.
An anionic peroxidase POIII, molecular weight 56 kDa, was purified from the roots of horseradish cv. Balady. The enzyme exhibited high activity towards o-phenylenediamine and guaiacol, while o-dianisidine had moderate peroxidase activity. Pyrogallol and p-aminoantipyrine had low affinity toward POIII. POIII was found to have a temperature optimum at 40 °C; the enzyme activity remained stable up to 40 °C and retained 87%, 51% and 29% of its activity at 50, 60 and 70 °C, respectively. The enzyme exhibited more than 50% of activity in the pH range between 4.0 and 8.0 with its pH optimum at 5.5. Several metal cations had partial inhibitory effects toward POIII. Fe3+ enhanced the activity of the enzyme by 160% at 5 mM. All the metal chelators caused partial inhibitory effects toward POIII, except for EDTA at 1 mM, which had no effect on the enzyme.  相似文献   
102.
At physiological hydrogen-ion concentration, p-hydroxybenzoate esters have been found to exert a synergistic effect on the lytic activity of lysozyme; the effect being increased with increasing the size of the aliphatic chain. Although the investigated parabens were proved to bind in significant quantities with lysozyme, however, such additives fail to mask the formation of substrate-lysozyme complexes. The observation was further extended to some organic mercurials with essentially similar results.

At different enzyme concentration levels, phonylmercuric acetate was proved to be the most superior potentiator, whereas, methyl paraben displayed a negligible role.

in the light of the findings obtained, the synergistic effect was interpreted on the basis of the preferential orientation of the substrate on the enzyme binding sites. Such an orientation seems to be more accessible in presence of preservatives.  相似文献   
103.
Robotics application in colour recognition using fiber optic cabled sensors interfaced with robot controller and Programmable Logic Controller (PLC) is discussed in this paper. The sensors send input signals to the robot controller and the specified program will be executed with respect to the triggered input. The aim of this research work is to recognize colour by pin point detection and sorting of object specimens with respect to their colour attributes, which includes hue, saturation and luminance level. The controller programs were designed to control the robot and the conveyor belt independently parallel to each other via relays, to be synchronized during operation. Finally, the calculative results were verified experimentally and the real time implementation was carried out. It can be observed how controllers are integrated and synchronized in a system to perform a desired operation without conflict using real time applications such as chemical, pharmaceutical, agricultural, food industries and even recycling.  相似文献   
104.
Knowledge-based neural networks (KBNNs) can be used as expert system knowledge bases. This approach shifts the interests in using connectionist knowledge bases for inferencing in an interactive fashion and giving reasonable justifications for their conclusions. The primary goal of this article is to present a good inference and control mechanism for such knowledge bases. For this purpose, the article develops a stand alone inference engine that uses a connectionist knowledge base, seeks to reduce the amount of data requested in order to reach a conclusion, and explains how a particular conclusion was reached. The inference engine was evaluated on illustrative example applications. Results obtained demonstrate that in spite of its simplicity the presented technique is superior to other techniques over sparse input knowledge bases.  相似文献   
105.
Abstract

Water scarcity in Jordan is a significant constraint to development, with limited available water and financial resources. As population and economic activity increase, it will be necessary to implement national strategies that seek to balance the present needs and those of future generations. Multiple variables associated with agricultural crops, industries, and the impact of climate change, were incorporated into a Decision Support System (DSS). The DSS utilized Analytical Hierarchy Process (AHP), which resulted in the prioritization of sustainable water policies for management in the Azraq Basin. The inputs to the DSS were generated through application of Modflow (groundwater), stochastic, and Penman Montieth models and through calculations of water productivity for agricultural and industrial sectors. The results of the DSS make recommendations as to how to enhance long-term sustainability of water resources in Azraq, while allowing for water utilization and economic growth. It is recommended for future planning that further research of the impacts to water resources must be conducted at local and national levels and linked to regional and global climate change prediction. It can be concluded that the DSS tool and AHP are potentially positive contributions to the process of decision- making for selection and ranking of alternatives and policies and for help in solving problems that include conflicting criteria.  相似文献   
106.
107.
Bleaching of rice straw soda pulp was investigated under various conditions. The rate of the chlorination and hypochlorite reactions were studied; the best properties were attained by shortening the chlorination time to about 20 min. The extraction efficiency of ammonium hydroxide on chlorinated soda pulp was also investigated. The effectiveness of extraction can be deduced from the reduction of the kappa number, cuprammonium viscosity and the brightness obtained after the hypochlorite step. Extraction can be carried out with ammonium hydroxide instead of sodium hydroxide used in the conventional method. The strengths of unbleached and fully bleached pulps were evaluated. The fully bleached ammonium hydroxide extracted pulps were beaten faster and were usually stronger than the corresponding pulps extracted with sodium hydroxide.  相似文献   
108.
109.
Project scheduling is a key objective of many models and is the proposed method for project planning and management. Project scheduling problems depend on precedence relationships and resource constraints, in addition to some other limitations for achieving a subset of goals. Project scheduling problems are dependent on many limitations, including limitations of precedence relationships, resource constraints, and some other limitations for achieving a subset of goals. Deterministic project scheduling models consider all information about the scheduling problem such as activity durations and precedence relationships information resources available and required, which are known and stable during the implementation process. The concept of deterministic project scheduling conflicts with real situations, in which in many cases, some data on the activity' s durations of the project and the degree of availability of resources change or may have different modes and strategies during the process of project implementation for dealing with multi-mode conditions surrounded by projects and their activity durations. Scheduling the multi-mode resource-constrained project problem is an optimization problem whose minimum project duration subject to the availability of resources is of particular interest to us. We use the multi-mode resource allocation and scheduling model that takes into account the dynamicity features of all parameters, that is, the scheduling process must be flexible to dynamic environment features. In this paper, we propose five priority heuristic rules for scheduling multi-mode resource-constrained projects under dynamicity features for more realistic situations, in which we apply the proposed heuristic rules (PHR) for scheduling multi-mode resource-constrained projects. Five projects are considered test problems for the PHR. The obtained results rendered by these priority rules for the test problems are compared by the results obtained from 10 well-known heuristics rules rendered for the same test problems. The results in many cases of the proposed priority rules are very promising, where they achieve better scheduling dates in many test case problems and the same results for the others. The proposed model is based on the dynamic features for project topography.  相似文献   
110.
This research was conducted to study the efficacy of sodium alginate and gelatin coating materials in improving the quality of pastirma. Pastirma was coated with traditional, alginate or gelatin coatings, stored at 4 °C for 4 weeks and examined weekly. Alginate and gelatin coated-pastirma revealed lower TBARS values which was within the acceptable limit (0.67 and 0.86 mg/kg) until the end of storage, however, the TBARS values of traditionally coated pastirma reached 1.33 by the end of storage. Edible coating delayed respiration rate with improvement of the color when compared with traditionally coated one. Oxygen concentration increased from 4.21 mg/kg/h in traditionally coated pastirma to 12.56 and 9.79 in alginate and gelatin coated ones, respectively. Meanwhile, CO2 concentration decreased from 10.40 mg/kg/h in traditionally coated pastirma to 4.89 and 6.07 mg/kg/h in alginate and gelatin coated ones, respectively. Moreover, a distinct improvement in all sensory attributes has been observed.  相似文献   
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