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161.
Farouk  Tebbal  王瀛 《人类居住》2006,(1):32-34
在全世界,有上亿城市居民没有片瓦遮顶,无处求助,享受不到健康服务、受教育、使用清洁的水或卫生设施,没有各项权利。因为他们的境遇悲惨,大多数无家可归者实际上并不知道他们拥有权利,更不用说如何使用权利。他们不被列入人口普查报告中。他们生活在城市中,却不属于城市。我们看得见他们,但实际上.存行政意义上.他们并不存在。  相似文献   
162.
In this paper, a class of Bidirectional Associative Memory neural networks with time-varying weights and continuously distributed delays is discussed. Sufficient conditions are obtained for the existence and uniqueness of weighted pseudo-almost periodic solution of the considered model and numerical examples are given to show the effectiveness of the obtained results.  相似文献   
163.
In this article, a new design of a compact printed rectangular antenna for wireless local area network (WLAN) applications in 802.11a is investigated. The defected ground structure (DGS) technique is successfully used to reduce the ground plane by cutting a large slot to achieve significant miniaturization. The ground plane structure consists of inverted ‘L’ shape. The rectangular radiating element has a size of 6 × 5 mm2 and is connected to a microstrip transmission feed line. The simulated and measured resonance frequency of the single‐band antenna is approximately 5.8 GHz and may cover an impedance bandwidth of 1 GHz for the measurement and 1.65 GHz for the simulation. The simulated and the measured data are in good agreement. The proposed antenna is very compact (10 × 6 mm2) and its impedance bandwidth is suitable for the 5.2‐5.8 GHz WLAN communication systems.  相似文献   
164.
Many data mining applications have a large amount of data but labeling data is usually difficult, expensive, or time consuming, as it requires human experts for annotation. Semi-supervised learning addresses this problem by using unlabeled data together with labeled data in the training process. Co-Training is a popular semi-supervised learning algorithm that has the assumptions that each example is represented by multiple sets of features (views) and these views are sufficient for learning and independent given the class. However, these assumptions are strong and are not satisfied in many real-world domains. In this paper, a single-view variant of Co-Training, called Co-Training by Committee (CoBC) is proposed, in which an ensemble of diverse classifiers is used instead of redundant and independent views. We introduce a new labeling confidence measure for unlabeled examples based on estimating the local accuracy of the committee members on its neighborhood. Then we introduce two new learning algorithms, QBC-then-CoBC and QBC-with-CoBC, which combine the merits of committee-based semi-supervised learning and active learning. The random subspace method is applied on both C4.5 decision trees and 1-nearest neighbor classifiers to construct the diverse ensembles used for semi-supervised learning and active learning. Experiments show that these two combinations can outperform other non committee-based ones.  相似文献   
165.
A glass system was prepared from reagent grade chemicals having the formula 58 mol % B2O3 - 22 mol % CaO - (20 - ) mol % Al2O3 - mol % Fe2O3, where has different values between 2 and 20 mol %.The molar volume () and magnetic susceptibility () of these glasses has been measured as a function of Fe2O3 content. The values of and were found to increase as the Fe2O3 content in the glass increases in the region between 2 and 8 mol % and in the region where the content is greater than 10 to 16 mol %, while a decrease was found for samples having an Fe2O3 content of 10 mol % and more than 16 mol %. These results could be explained by the change in coordination of iron from FeO6 to FeO4, and also the change of Fe3+ to Fe2+ and change of Fe2+ from six coordination to four coordination.  相似文献   
166.
A new bifunctional reactive disperse dye containing a temporarily anionic sulphatoethylsulphone and a nonionic disulphide bis(ethylsulphone) groups was synthesised and applied to nylon 6 fabric by the exhaust dyeing at a variety of pH and temperature conditions. A monofunctional reactive disperse dye containing only nonionic disulphide bis(ethylsulphone) group was also synthesised and its dyeing behaviour was compared with the bifunctional dye. The bifunctional reactive disperse dye exhibited high exhaustion and fixation values at pH 6 and 120 °C. The results also indicate that the combination of temporarily anionic and nonionic reactive groups of the bifunctional dye provided great enhancement in dyeing performance compared to that of the monofunctional dye. The dyes also showed very good levelling and fastness properties on nylon 6 fabric.  相似文献   
167.
The surface properties of a stannic oxide gel and its thermal dehydration products obtained both in vacuo and in the presence of air in the temperature range 100–600°C have been examined by N2 adsorption. Phase and structural changes have been followed by differential thermal analysis and X-ray diffractometry. Complete pore structure analysis showed that samples dehydrated at or below 250°C were microporous. Above 250°C the pores were found to widen with increase of temperature, the widening occurring concurrently with the crystallisation process. Doping with cations of lower valency (Li+ and Al3+) than the host cation (Sn4+) had little effect on the pore structure and specific surface area for the low temperature samples (≥250°), whereas at higher temperatures, e.g. 600°C, it increased the specific area remarkably. The dope ions produce oxygen vacancies and hinder or retard sintering in SnO2.  相似文献   
168.
A Li–borate glass system doped with samarium and europium has been prepared by a conventional melt quenching technique. Europium content was kept constant at 0.01 mol%. The general formula was
xSm2O3 + (100 − x) [0.84B2O3 + 0.15Li2O + 0.01Eu2O3]
where x = 0.1, 0.2, 0.5, 0.6 and 0.7 mol%. The density was measured and the corresponding molar volume was evaluated .The former was found to increase by increasing Sm while the later exhibits opposite trend. The average optical basicity, Λth, electron negativity χ2av and electron polarizability α2− were calculated for the prepared compositions. Infrared spectra were obtained at room temperature for the prepared glasses before and after γ irradiation. The results showed that the three main appeared bands are most likely due to the bending and/or stretching vibration of both tetrahedral BO4 and triagonal BO3 borate units. ESR spectra were recorded at room temperature before and after γ-irradiation. It was found that the oxygen atoms of BO3 units are responsible for the formation of the hole paramagnetic centers after irradiation in the glass matrix.  相似文献   
169.
Farouk MM  Swan JE 《Meat science》1998,50(2):235-243
The effect of rigor temperature (RT, 35 versus 10°C), increased ionic concentration (MS: 0 versus 0·2% mixed salts), oxidized lipids (OL, 0 versus 1% added oxidized fat), increased free amino acids (FAA, 0 versus 0·3% added mixture of amino acids), fat content (FC, 0 versus 15% added fat) and excluding atmospheric gases (V, 0 versus 99·9% vacuum) on protein functionality in mince stored 1 month at -20°C was studied using a complete 2(6) factorial design. All factors studied affected the functional properties of beef. Fresh 24hr samples that entered rigor at 35°C had lower total (TPS), myofibrillar (MPS) and sarcoplasmic (SPS) protein solubilities than samples entering rigor at 10°C (p<0·01). During frozen storage, RT, MS and OL alone did not affect protein solubilities, FAA increased TPS but did not affect MPS and SPS, increasing the meat's fat content raised TPS and SPS but did not affect MPS, applying a vacuum increased TPS and MPS but lowered SPS (p<0·05). Cook yield of frozen stored mince increased with higher FAA but decreased with higher fat content, and the peak force of patties made from frozen stored mince was lowered by increased MS and low FC during storage. Various significant interactions are tabulated and discussed.  相似文献   
170.
The phase behaviour of mixtures of salt soluble meat proteins, kappa (κ) and iota (ι) carrageenan in non-gelling conditions (45 °C) were determined at pH 5.6, 6.2 and 7.1. The concentration of meat proteins ranged from 0.1 to 1.0 percent and that of κ-carrageenan and ι-carrageenan from 0.02 to 0.3 percent in the mixtures. Mixtures separated under gravity to form soluble/liquid and gelled/complex phases. For meat proteins- κ-carrageenan mixtures, phase separations at all meat protein/carrageenan ratios were observed. For meat protein-ι-carrageenan mixtures, soluble complexes were formed at low meat protein to ι-carrageenan ratios and gels at higher ratios. The yield of the complex/gels increased with the increase in the concentration of the meat proteins and carrageenans and decreased with increase in the pH of the initial mix. The complex/gels formed became stronger with the increase in carrageenan in the mix and with κ-carrageenan compared to ι-carrageenan. Chemical analyses and scanning electron and phase contrast microscopy indicated that in phase separated mixtures, the bulk of the meat proteins and carrageenan were found in the gel compared to the liquid phase; and that meat protein interacted with carrageenan in the gel and formed soluble complexes with carrageenan in the liquid phase. SDS-PAGE showed that the meat proteins that interacted to form the complex/gels with carrageenan included myosin heavy chain, α-actinin, actin, myosin light chains and proteins with molecular weights around 150 and 50 kD. The outcomes of the present study could be used in the formulation of multi-component foods with a range of consistencies containing meat proteins.  相似文献   
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