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101.
A consistent formulation for the bending of cross-ply laminated composite plates that possess non-homogeneous elastic properties is presented. Based on a third-order shear deformation plate theory, the governing equations are obtained using the principle of virtual work. With the help of the small parameter method, a wide variety of results are presented for the symmetric and antisymmetric analysis of non-homogeneous rectangular laminated plates. The influence of non-homogeneity, lamination schemes, aspect ratio and material anisotropy on the deflections and stresses is investigated. The new results for non-homogeneous response of composite plates should serve as bench marks for future comparisons. 相似文献
102.
Khalid Fares C. M. G. C. Renard Qamar R'Zina & Jean-François Thibault 《International Journal of Food Science & Technology》2001,36(1):35-46
Summary Cell-wall polysaccharides were isolated as alcohol-insoluble residues (AIR) from Moroccan sugar beet slices at two stages of the harvest season (early and late samples). Pectins and hemicelluloses were extracted by a sequential treatment with water, EDTA, hot dilute hydrochloric acid, cold dilute sodium hydroxide, cold 1 M and 4 M sodium hydroxide and finally water at pH 7. The highest extraction yields were obtained for the dilute acid and alkali treatments, which extracted pectins rich in arabinose. The extracts from the late sample were rich in glucose which, was not retained on DEAE Sepharose CL 6 B, and which may come from microbial growth on the fields after harvesting. Yields for hemicelluloses after extraction with 1 M NaOH were 12% and 13% of AIR, respectively, for early and late beet slices, and after extraction with 4 M NaOH 5% and 6%, respectively. The extracts were rich in arabinose, xylose and glucose, and contained fucose and mannose. Fractionation on DEAE Sepharose gave one major non-retained fraction rich in neutral sugars, corresponding to xyloglucans and a minor retained fraction corresponding to heteroxylans, and residual pectins. Washing with water at pH 7 extracted pectins rich in rhamnose and galactose. 相似文献
103.
This paper presents elastic stress distributions near a cracktip in a continuous fiber composite. The material heterogeneity is explicitly accounted for by using the finite element method and a new Mesh Superposition Technique. This new technique superposes a fine mesh with heterogeneous material properties over a coarse mesh with homogeneous ones. The results indicate that the load transferred by fibers near a cracktip may be well described by the homogeneous orthotropic elastic K
1 field. A technique to postprocess the K
1 field to accurately obtain the detailed stress distributions within the fiber and matrix is also presented. 相似文献
104.
Cooking behaviour and acceptability of composite pasta made of semolina and toasted or partially defatted soy flour 总被引:1,自引:0,他引:1
The effects of the replacement of increasing amounts of semolina with toasted or partially defatted soy flour on dough rheological indices and spaghetti quality were evaluated. The replacement caused the dough weakening and the increase of the tenacity-extensibility ratio. Due to the competition of soy proteins and starch for water, the substitution of increasing amounts of semolina was able to increase the optimal cooking time without significant changes of the ratio between the increase in weight or diameter and the weight or diameter of dry spaghetti (ΔP/P and ΔD/D) but with a significant slowing of the ΔL/L (ratio between the increase in length and the length of dry spaghetti) increase during overcooking. Around the optimal cooking time, the release of organic matter was higher in pasta made exclusively of semolina whereas the sensory response was similar for control and composite spaghetti. Statistically significant correlations were obtained between protein content of the flour mixtures or dough alveographic indices and the cooking behaviour of semolina-soy spaghetti according to non-linear regression models. In particular, both protein content and alveographic indices allowed to predict approximately 92-94% of the variation of cooking losses and, in a lower measure, the variation of bulkiness and elasticity of semolina-soy spaghetti. 相似文献
105.
106.
Self-consolidating concrete subjected to high temperature: Mechanical and physicochemical properties
This paper presents an experimental study on the performance of self-consolidating concrete (SCC) subjected to high temperature. Two SCC mixtures and one vibrated concrete were tested. These concrete mixes were developed in the French National Project B@P. Mechanical and microstructural properties were studied at ambient temperature and after heating. We studied compressive strength, flexural strength, bulk modulus of elasticity, porosity and permeability. For each test, the specimens were heated at a rate of 1 °C/min up to different temperatures (150, 300, 450 and 600 °C). In order to ensure a uniform temperature throughout the specimen, the temperature was held constant at the target temperature for 1 h before cooling. In addition, the specimen mass was measured before and after heating in order to determine the loss of water during the test. The results allowed us to analyze the degradation of SCC and vibrated concretes due to heating. 相似文献
107.
Clara Fares Pasquale Codianni Franca Nigro Cristiano Platani Francesca Scazzina Nicoletta Pellegrini 《Journal of the science of food and agriculture》2008,88(14):2435-2444
BACKGROUND: Emmer wheat (T. turgidum ssp. dicoccum Schrank) is an old Mediterranean crop grown for centuries and progressively replaced with durum wheat. Although most of its supposed nutritional properties have not yet been scientifically proven, emmer seems to be appreciated for its content of dietary fibre, resistant starch (RS) and antioxidant compounds. The aim of this work was to evaluate the profiles of dietary fibre, starch and antioxidant compounds in raw materials and in semolina of 13 selected emmer lines and their parents (a durum wheat cultivar and an old T. turgidum dicoccum population). Moreover, the cooking effect on functional properties and total antioxidant capacity (TAC) of pasta derived from emmer lines and the in vivo effect of pasta on postprandial glucose response were determined. RESULTS: Processing and cooking affected the dietary fibre content of pasta: the insoluble dietary fibre content was increased, while a slight loss of soluble dietary fibre was observed. Cooking also resulted in a noteworthy increase in amylose and RS content. The antioxidant compounds (i.e., tocols and carotenoids) as well as TAC decreased dramatically after cooking. Pasta obtained with an emmer line significantly lowered the glycaemic index, strengthening the concept of pasta product as a source of functional components in the habitual diet. CONCLUSIONS: The results showed that emmer semolina is suitable for the preparation of pasta with good organoleptic quality and represents a source of RS and fibre, but processing and cooking negatively affected the amount of antioxidant compounds detected in the wholemeal. Copyright © 2008 Society of Chemical Industry 相似文献
108.
The dogma of engineering oncolytic viral vectors has shifted from emphasizing the viral lysis of individual cancer cells to the recruitment and coordination of the adaptive immune system to clear the tumor. To accomplish this, researchers have been adding several classes of transgenes to their preferred viral platforms. The most prevalent of these include antibodies and targeting moieties, interleukins and cytokines, and genes which rely on small molecule co-administration for tumor killing. Most current vectors rely exclusively on one of these types of transgenes to elicit the desired immune response to clear tumors, but are not mutually exclusive, with several larger OVs armed with several of these factors. The common theme of emerging armed vectors is to simply initiate or enhance infiltration of effector CD8+ T cells to clear the tumor locally at OV infection sites, and systemically throughout the body where the OV has not infected tumor cells. The precision of oncolytic vectors to target a cell type or tissue remains its key advantage over small-molecule drugs. Unlike chemo- and other drug therapies, viral vectors can be made to specifically infect and grow within tumor cells. This ensures localized expression of the therapeutic transgene to the diseased tissue, thereby limiting systemic toxicity. This review will examine the immunomodulating transgenes of current OVs, describe their general effect on the immune system, and provide the rationale for each vector’s use in clearing its targeted tumor. 相似文献
109.
Graft Copolymerization onto Starch–I. Synthesis and Optimization of Starch Grafted with N-tert-Butylacrylamide Copolymer and its Hydrogels 总被引:1,自引:0,他引:1
Mohammad M. Fares Adeeb S. El-faqeeh Mohammad E. Osman 《Journal of Polymer Research》2003,10(2):119-125
Grafting of N-tert-butylacrylamide (BAM) onto starch in aqueous medium initiated by ceric ammonium nitrate ion has been studied under N2 atmosphere. The optimum conditions with respect to monomer concentration, initiator concentration, polymerization temperature, polymerization time and material to liquor ratio were studied in terms of percent of grafting efficiency (%GE) and percent of grafting yield (%GY). The optimum conditions obtained for the grafting of BAM on 1.0 g starch were: [BAM]=0.020 mol/L, [CAN]=0.91×10–3 mol/L, Temperature=30C, and Time=240 min. Starch-g-BAM copolymer was characterized by FTIR, TGA for thermal stability, X-ray diffraction (XRD) for the crystallinity and scanning electron microscope (SEM) for surface morphology of the copolymer. Acid hydrolysis and viscosity average molecular weight (M
v) of copolymer were evaluated for the copolymer. Hydrogels prepared by grafting of BAM onto gelatinized starch showed maximum water uptake and moisture retain of 162% and 63% respectively. 相似文献
110.
In this paper we propose to adopt a learning-based encoding method for age estimation under unconstrained imaging conditions. A similar approach [Cao et al., 2010] is applied to face recognition in real-life face images. However, the feature vectors are encoded in hard manner i.e. each feature vector is assigned to one code. The face is divided into patches where a code histogram is built for each patch. However, the codebook is learned using sample features from the entire face. 相似文献