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71.
Multipurpose margarine (MPM) or water-in-oil (w/o) emulsion systems were prepared using palm oil (PO)/palm stearin (PS) blends as continuous phases and stabilized by monoacylglycerol (90% monoester) as emulsifier. Experimental analyses of three out of six models of MPM showed that MPM1, MPM2 and MPM3 had low workability force and weaker network structure. As results the solid fat content (SFC) at 28 °C, consistency, storage modulus (G′) and softness were 25%, 15.5 × 102 kPa, 2.62 × 102 kPa and 30 mm ease of cone penetration, respectively. Furthermore, examination microscopy of the images concerning MPM1, MPM2 and MPM3 revealed the presence of symmetrical crystals after 60 days of storage, whereas the MPM4, MPM5 and MPM6 models exhibited asymmetrical crystals during same incubation time. These results indicated that the diminution of PS versus PO contents induced the retardation of phase transition from less stable beta-prime (β′) crystals to the more stable beta (β) crystals during storage.  相似文献   
72.
The main goal of the present work was to assess the mechanism of crystallisation, more precisely the dominant component responsible for primary crystal formations and fat agglomerations. Therefore, DSC results exhibited significant effect on temperature transition; peak sharpness and enthalpy at palm stearin (PS) levels more than 40 wt.%. HPLC data demonstrated slight reduction in the content of POO/OPO at PS levels less than 40 wt.%, while the excessive addition of PS more than 40 wt.% increased significantly PPO/POP content. The pNMR results showed significant drop in SFC for blends containing PS less than 40 wt.%, resulting in low SFC less than 15% at body temperature (37 °C). Moreover, the values of viscosity (η) and shear stress (τ) at PS levels over 40 wt.% expressed excellent internal friction of the admixtures. All the data reported indicate that PPO/POP was the major component of primary nucleus developed. In part, the levels of PS should be less than 40 wt.%, if these blends are designed to be used for margarine production.  相似文献   
73.
The main aim of this work was to study and compare the mechanical and thermal properties of hybrid polypropylene (PP) composites and single‐filler PP composites. With two main types of mineral fillers—calcium carbonate (CaCO3) and talc—PP composites of different filler weight ratios (talc/CaCO3) were compounded with a twin‐screw extruder and then injection‐molded into dumbbell specimens with an injection‐molding machine. Tensile, flexural, and impact tests were performed to determine and compare the mechanical properties of the hybrid and single‐filler PP composites. A synergistic hybridization effect was successfully achieved; the flexural strength and impact strength were highest among the hybrids when the PP/talc/CaCO3 weight ratio was 70:15:15. The nucleating ability of the fillers and its effects on the mechanical properties were also studied with differential scanning calorimetry. Because of the influence of talc as the main nucleating agent, the hybrid fillers showed significant improvements in terms of the nucleating ability, and this contributed to the increase in or retention of the mechanical properties of the hybrid composites. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3327–3336, 2004  相似文献   
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Doughs containing mixtures of sago and wheat flours of differing protein content at different levels of sago substitution (10, 15, 20, 25, 30, 40 and 50%) were prepared as follows: sago + high protein wheat (HPW) flour, sago + medium protein wheat (MPW) flour and sago + low ? protein wheat (LPW) flour. The viscoelasticity of doughs from control sago and wheat flours and sago/wheat flour mixtures was determined using a Braberder farinograph. It was found that arrival time increased with increasing protein content in the mixture. Peak time for control wheat flours and sago/wheat flour mixtures increased with increasing protein content. Dough stability, 20 min drop and water absorption were found to decrease as the sago proportion in the mixture decreased. The 50% sago/LPW mixture was unable to form a dough. Breakdown times for control HPW flour and HPW flour mixtures were the highest, followed by MPW flour and then LPW flour. However, breakdown time for control MPW flour was higher than that for HPW flour mixtures. The same trend was observed at all ratios of mixture over the whole experiment. Copyright © 2004 Society of Chemical Industry  相似文献   
76.
The progressive development of functional foods and herbal medicine has enthused many researchers to explore novel plant sources. In this regard, the rambutan fruit (Nephelium lappaceum L.) appears to be a promising candidate primarily due to its nutritional and bioactive compositions. With that, this particular review presents a systematic depiction of chemical composition and bioactivities of the rambutan fruit peel, pulp, and seed. Numerous reports do not provide sufficient data pertaining to cultivar, stage of maturity or the environment of fruit, yet the summarized data suggest a myriad of therapeutic potentials derived from the rambutan fruit. In fact, the rambutan fruit has been proven to possess phytochemicals that demonstrate anticancer, anti-allergic, anti-obesity, antidiabetic, anti-HIV, antimicrobial, anti-dengue, anti-hypercholesterolemic, and antihyperglycemic effects in varied in-vitro and in-vivo models. Nonetheless, advance studies are indispensable to further highlight the therapeutic mechanisms involved. In addition, a phytochemical analysis would further establish the rambutan fruit as a sustainable candidate in developing functional foods and pharmaceuticals.  相似文献   
77.
Telecommunication Systems - The future wireless Fifth Generation (5G) communication network required a higher bandwidth in order to achieve greater data rate. It will be largely characterized by...  相似文献   
78.
Journal of Mechanical Science and Technology - This paper aims to assess the fatigue reliability of random loading signals of a suspension coil spring using probabilistic approaches. Strain time...  相似文献   
79.
Exposure to vibration has various physiological effects on vehicle passengers. Engine is one of the main sources of vehicle vibration. The major causes of engine vibration are combustion forces transmitted through the pistons and connection rods. Evaluation of sources is the first step to attenuate this vibration. Assessment of these sources is not an easy task because internal parts of machinery are not accessible. Often, instrumentation for such systems is costly, time consuming and some modifications would be necessary. Aim of the first part of this paper was to validate an inverse technique and carry out mobility analysis on a vehicle crankshaft to achieve matrix of Frequency Response Functions (FRFs). Outcomes were implemented to reconstruct the applied force for single and multiple-input systems. In the second part, the validated inverse technique and FRFs were used to estimate piston forces of an operating engine. Bearings of crankshaft were chosen as nearest accessible parts to piston connecting rods. Accelerometers were connected to the bearings for response measurement during an ideal engine operation. These responses together with FRFs, which were estimated in the previous part, were utilised in the inverse technique. Tikhonov regularization was used to solve the ill-conditioned inverse system. Two methods, namely L-curve criterion and Generalized Cross Validation (GCV), were employed to find the regularization parameter for the Tikhonov method. The inverse problem was solved and piston forces applied to crankpins were estimated. Results were validated by pressure measurement inside a cylinder and estimating the corresponding combustion force. This validation showed that inverse technique and measurement outcomes were roughly in agreement. In presence of various noise, L-curve criterion conduces to more robust results compared to the GCV method. But in the absence of high correlation between sources (f>600 HzHz), the GCV technique leads to more accurate results. This research shows that inverse techniques have great ability to estimate vibration sources inside the machinery.  相似文献   
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Recent trend shows that one of the crucial problems faced while using radio frequency to track the objects is the inconsistency of the signal strength reception, which can be mainly due to the environmental factors and the blockage, which always have the most impact on the tracking accuracy. Besides, three dimensions are more relevant to a warehouse scanning. Therefore, this study proposes a highly accurate and new three-dimensional (3D) radio frequency identification-based indoor tracking system with the consideration of different attenuation factors and obstacles. The obtained results show that the proposed system yields high-quality performance with an average error as low as 0.27?m (without obstacles and attenuation effects). The obtained results also show that the proposed tracking technique can achieve relatively lower errors (0.4 and 0.36?m, respectively) even in the presence of the highest attenuation effect, e?=?3.3 or when the environment is largely affected by 50% of the obstacles. Furthermore, the superiority of the proposed 3D tracking system has been proved by comparing with other existing approaches. The 3D tracking system proposed in this study can be applicable to a warehouse scanning.  相似文献   
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