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41.
A bifunctional reactive disperse dye containing two temporarily anionic sulphatoethylsulphone groups was synthesised and applied to nylon 6 fabric by exhaust dyeing at a variety of pH levels and temperatures. A monofunctional reactive disperse dye containing one temporarily anionic sulphatoethylsulphone group was also synthesised, and its dyeing behaviour was compared with the bifunctional dye. The bifunctional reactive disperse dye exhibited high exhaustion and total fixation yield under alkaline conditions. The results also indicate that the introduction of two temporarily anionic sulphatoethylsulphone groups of the bifunctional dye gave an enhancement in dyeing performance compared with that of the monofunctional dye. The dyes also showed very good levelling and fastness properties on nylon 6 fabric.  相似文献   
42.
This paper presents a general methodology to improve risk assessment in the specific workshops of semiconductor manufacturers. We are concerned, in this case, with the problem of equipment failures and drifts. These failures are generally observed, with delay, during the product metrology phase. To improve the reactivity of the control system, we propose a predictive approach based on the Bayesian technique. Increased use of these techniques is the result of the advantages obtained. This approach allows early action to maintain, for example, the equipment before it can drift. Also, our contribution consists in proposing a generic model to predict the equipment health factor (EHF), which will define decision support strategies on preventive maintenance to avoid unscheduled equipment downtime. Following the proposed methodology, a data extraction and processing prototype is also designed to identify the real failure modes which will instantiate the Bayesian model. EHF results are decision support elements. They can be further used to improve production performance: reduced cycle time, improved yield and enhanced equipment effectiveness.  相似文献   
43.
Bovine M. semimembranosus from different sexes of cattle were held at temperatures ranging from 0 to 35 °C until rigor and aged for up to 9 weeks. The waterholding capacity (WHC) of the beef increased with ageing as evidenced by the decline in drip loss measured gravimetrically, centrifugally and by pressure. Drip viscosity (P < 0.01), meat protein extractability (P < 0.05), spreadability (P < 0.01) and compressibility also increased with ageing. Evidence of structural changes was seen in SDS-PAGE confirming the physical changes. Meat spreadability under pressure and WHC were higher in samples with inherently higher pH relative to lower pH. The outcome of this study supports a hypothesis that the increase in WHC with ageing is due to the breakdown in meat structure and the creation of “sponge effect”, which disrupts the channels through which moisture is lost and physically entraps the free water in meat and reduce the amount that drips out.  相似文献   
44.
This paper describes a novel design technique for hardening sequential circuits against Single Event Transients (SETs) and Single Event Upsets (SEUs) in non-volatile FPGAs. Double Modular Redundancy (DMR) is used to detect the presence of a SET in a sequential circuit. However, DMR solutions are only able to detect SET’s and not mask or correct them. Therefore, extra functionality is required to mask and correct the error after it has been detected. The central idea of the method proposed is to “freeze” the sequential circuit at a particular state when a SET is detected. As soon as the SET dissipates, the circuit is “unfrozen” so that it can continue with normal operation. Due to the short SET lifetime versus much longer circuit clock periods, the “frozen” state will normally not last more than one clock period. The proposed scheme is suitable for delay-insensitive applications requiring minimal hardware overhead.The proposed DMR method is thoroughly tested on ITC99 benchmarks. With a small delay of one clock period whenever a SET is detected, the proposed method offers immunity against the errors caused by SETs in non-volatile FPGA systems.  相似文献   
45.
Functional stability of frozen normal and high pH beef   总被引:1,自引:0,他引:1  
The functional properties of whole, diced or minced high and normal pH beef were determined after 0, 1, 2, 3 and 7 month’s storage. There was no interaction between pH, degree of comminution and storage time for most of the attributes measured. Regardless of storage time or comminution method, high pH meat had significantly (P < 0.001) higher sarcoplasmic protein solubility, water holding capacity, cooked batter torsion stress and strain, yield and emulsion stability than normal pH meat. Normal pH meat had significantly (P < 0.01) higher myofibrillar protein solubility and hue angle than high pH meat. Water holding capacity significantly (P < 0.01) decreased and hue angle increased with the increase in the degree of comminution. Protein solubility in raw meat and the cooked batter stress, strain, yield and emulsion stability of both high and normal pH meat deteriorated with time. However, this deterioration was faster in the normal pH meat compared to high pH meat except for total and myofibrillar protein solubility. Within the parameters of the present study, it is concluded that frozen high pH meat possesses superior functional attributes compared to normal pH meat regardless of the degree of comminution or storage time.  相似文献   
46.
Effects of rigor temperature and electrical stimulation on venison quality   总被引:2,自引:0,他引:2  
The effects of rigor temperature and electrical stimulation on venison quality were assessed using venison longissimus dorsi muscle. In the first trial, effect of rigor temperature (0, 15, 25, 30, 35 and 42 °C) and time post-mortem (at rigor, 3, 7 and 14 days) on drip and cooking losses, % expressible water (water holding capacity, WHC), sarcomere length, protein solubility, meat tenderness and colour were investigated. In the second trial, the effects of rigor temperature (15 and 35 °C), electric stimulation (stimulated or not stimulated) and time (at rigor, 3 and 6 weeks post-mortem) on tenderness and colour were further investigated. Results of the first trial showed no clearly established trends of the effect of rigor temperature and time on the cooking and drip losses and protein solubility except venison muscles that went into rigor at 42 °C tended to have higher drip loss and lower protein solubilities compared to muscles that went into rigor at the other temperatures. Venison water holding capacity (WHC) decreased with the increase in rigor temperature (P < 0.001) and venison became more tender with time post-mortem. Venison colour improved with increasing rigor temperature. During display, samples that went into rigor at 15, 25 and 35 °C had the lowest and those at 0 and 42 °C had the highest rate of change of redness (a*) value with time. In the second trial, tenderness was improved by stimulation (P = 0.01). Redness (a*) values were affected by rigor temperature (P < 0.01) and post-mortem time (P < 0.001) but not by electrical stimulation. It is concluded that venison tenderness can be improved via the manipulation of rigor temperature to obtain acceptable level of tenderness early post-mortem with less damaging effect on colour stability.  相似文献   
47.
Blends of low‐density polyethylene (LDPE) and polylactide (PLA) were prepared by melt coextrusion. The plastic behavior of the LDPE/PLA blends was investigated at room temperature under uniaxial tension by means of a video‐controlled system. The constitutive behavior was analyzed in terms of the variations of true stress vs. true strain at constant true strain rate. With increasing concentrations of PLA, the blend show: (i) higher Young's modulus, (ii) stiffer viscoelastic response, (iii) increase of elastic limit stress, and (iv) earlier fracture. Particular attention was paid to the evolution of the volume strain with the applied strain. While dilatation begins very lately for the neat LDPE, the LDPE/PLA blends show increasing deformation damage as the PLA content is increased. Scanning electron microscopy of deformed specimens shows that cavitation occurs preferentially at the poles of the PLA particles whose adhesion to the LDPE matrix seems very weak despite the partial grafting of polyethylene chains with maleic anhydride. POLYM. ENG. SCI., 2011. © 2010 Society of Plastics Engineers.  相似文献   
48.
The worldwide volume and value of trade in halal and kosher meat and co-products are huge. Muslim countries alone consumed meat estimated to be worth USD 57.2 billion in 2008. The halal and kosher principles that govern the production of red meat have many similarities, as well as some fundamental differences. Perhaps the most significant difference is that at the time of slaughter, the animal needs only to be alive to meet the minimum halal requirement, but must be both alive and conscious for kosher. It is for this reason that reversible pre-slaughter stunning is acceptable only for halal meat, although a compromise form of post-slaughter stunning is now considered kosher in some countries. Extensive research on animal physiology and welfare has characterised and optimised the methods for stunning livestock, and enabled advancement in associated technologies. This forms the basis for harmonising the religious and secular requirements for the protection of animal welfare at slaughter. These technologies and the associated processing practices for the industrial production of halal and kosher meat are reviewed in this paper.  相似文献   
49.
Farouk MM  Swan JE 《Meat science》1998,49(2):233-247
Within 45 min post-mortem, 10mm thick strips of semitendinosus muscle from both unstimulated and high voltage stimulated heifer sides were held at 0, 5, 10, 25 and 35 °C for 24 hr, during which they entered rigor. Half the samples were frozen and stored at -20 °C for one month. The pH, sarcomere length, drip, total (TPS), myofibrillar (MPS) and sarcoplasmic (SPS) protein solubilities, and Hunter L (?), a (?) and b (?) values were determined at 24 hr and on thawed samples. Electrical stimulation did not significantly affect any of the parameters measured. The ultimate pH of samples entering rigor at 10 and 25 °C was lower (p < 0.001) than that of samples held at the other temperatures. Rather surprisingly, there was no significant difference in sarcomere length due to rigor temperature. Samples entering rigor at 35 °C had lower TPS, MPS and SPS values than samples held at 0 to 25 °C (p < 0.001). The MPS increased with rigor temperature up to 25 °C (p < 0.001). Drip and total moisture losses, and Hunter L (?), a (?) and b (?) values also increased with rigor temperature (p < 0.001) whereas SPS decreased and NMR meat water spin-lattice relaxation time (T1) shortened with increasing rigor temperature (p < 0.001). Hue angle and cook loss decreased with rigor temperature in 24 hr samples but increased with rigor temperature in frozen samples. After frozen storage, SPS, T1, cook loss and Hunter L (?), a (?), b (?) values decreased, but TPS, MPS, drip losses and hue angle increased. There were significant (p < 0.05) correlations between SPS, hue angle, drip losses and T1.  相似文献   
50.
Real-Time Systems - Multi-core architectures pose many challenges in real-time systems, which arise from contention between concurrent accesses to shared memory. Among the available memory...  相似文献   
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