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BACKGROUND: In Tunisia the cuttlefish‐processing industry generates large amounts of solid wastes. These wastes, which may represent 35% of the original material and constitute an important source of proteins, are discarded without any attempt at recovery. This paper describes some functional properties and the angiotensin I‐converting enzyme (ACE)‐inhibitory activity of protein hydrolysates prepared by hydrolysis of cuttlefish (Sepia officinalis) by‐products with crude enzyme extract from Bacillus licheniformis NH1. RESULTS: Cuttlefish by‐product protein hydrolysates (CPHs) with different degrees of hydrolysis (DH 5, 10 and 13.5%) were prepared. All CPHs contained 750–790 g kg?1 proteins. Solubility, emulsifying capacity and water‐holding capacity increased while fat absorption and foaming capacity decreased with increasing DH. All hydrolysates showed greater fat absorption than the water‐soluble fraction from undigested cuttlefish by‐product proteins and casein. CPHs were also analysed for their ACE‐inhibitory activity. CPH3 (DH 13.5%) displayed the highest ACE inhibition (79%), with an IC50 value of 1 mg mL?1. CONCLUSION: Hydrolysis of cuttlefish by‐product proteins with alkaline proteases from B. licheniformis resulted in a product with excellent solubility over a wide pH range and high ACE‐inhibitory activity. This study suggests that CPHs could be utilised to develop functional foods for prevention of hypertension. Copyright © 2010 Society of Chemical Industry  相似文献   
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—In this article, a new nature-inspired metaheuristic technique called the differential search algorithm is proposed to solve the optimal power flow problem. The proposed differential search algorithm has been developed and tested under normal and contingency power system conditions. To show the effectiveness of the proposed method, it has been demonstrated on the standard IEEE 30-bus and IEEE 118-bus test systems with different objectives that reflect performance indices of the power system. Obtained results using the proposed technique indicate that the proposed differential search algorithm provides an effective, a robust, and a high-quality solution for the optimal power flow problem. The comparisons of the proposed differential search algorithm results with those reported in the literature reveal the potential and superiority of the proposed algorithm in terms of the optimal solution quality and robustness.  相似文献   
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Adsorption efficiency of orthophosphate from aqueous solution onto Posidonia oceanica fibers (POF) as a raw, natural and abundant material was investigated and compared with other common natural materials. A series of batch tests were undertaken to assess the effect of the system variables, i.e. initial aqueous orthophosphate concentration, contact time, adsorbent dosage, pH and temperature. Results indicate that orthophosphate uptake increased with increasing initial orthophosphate concentration, temperature and adsorbent dosage and decreased with increasing pH values. The maximum adsorption capacity (Q(m)) determined from the Langmuir isotherm was calculated to be 7.45 mg g(-1) for the studied orthophosphates concentration range of 15-100 mg L(-1), pH 7; adsorbent dosage of 2 g L(-1) and temperature of 20±2°C. The adsorption data were very well described by the pseudo-second order model predicting a chemisorption process. The energy dispersive spectroscopy (EDS) and FTIR analysis before and after adsorption of orthophosphate onto POF showed that the main involved mechanisms are ligand exchange between orthophosphate and Cl(-), SO(4)(2-) and OH(-) and precipitation with calcium. In comparison with other natural adsorbents, raw POF could be considered as one of the most efficient natural materials for the removal of orthophosphate with the possibility of agronomic reuse.  相似文献   
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Diabetic cardiovascular autonomic neuropathy increases the risk of deterioration in renal function and is associated with increased mortality in patients with renal failure. Type 1 diabetic patients with long diabetes duration, matched for age (38 +/- 9 years) and diabetes duration (28 +/- 8 years) were studied regarding the association between cardiovascular autonomic nerve function and different degrees of diabetic nephropathy. Eighteen patients were normo- (< 30 mg/l), six micro- (30-300 mg/l), and 13 macroalbuminuric (> 300 mg/l) based on urinary albumin concentrations in three separate morning samples. They were compared with 33 control subjects with similar age. Autonomic nerve function was evaluated by measuring the response of heart rate to deep breathing and active standing. Beat-to-beat finger artery blood pressure (Finapres) was tested during active standing. During deep breathing both change in heart rate (17 +/- 11, 9 +/- 7 and 4 +/- 3 beats/min) and ratio between expiratory and inspiratory R-R intervals (1.32 +/- 0.24, 1.14 +/- 0.15 and 1.05 +/- 0.04) decreased from normo- over micro- to macroalbuminuria (p < 0.05 vs normoalbuminuric and control subjects [17 +/- 5 beats/min and 1.28 +/- 0.10, respectively]). Similar results were obtained during active standing with respect to change in systolic arterial blood pressure (3 +/- 8, 2 +/- 13 and -6 +/- 11 mmHg; p < 0.05 vs control subjects [8 +/- 11 mmHg]). However, the response of diastolic arterial blood pressure or mean heart rate to standing up did not differ between any of the groups. The ratio of maximum to minimum R-R interval during the dynamic response of heart rate to active standing decreased with the degree of nephropathy (1.27 +/- 0.17, 1.11 +/- 0.11 and 1.05 +/- 0.06) with significantly higher values in patients with normo- compared with patients with macroalbuminuria (p < 0.05). All patients groups had significantly lower values than control subjects (1.46 +/- 0.22, p < 0.05). The overshoot of the blood pressure after an initial fall during active standing decreased with the degree of diabetic nephropathy. In conclusion, type 1 diabetic patients with long duration of diabetes have signs of cardiovascular autonomic neuropathy, the severity of which is related to the degree of nephropathy.  相似文献   
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Visual words that are masked and presented so briefly that they cannot be seen may nevertheless facilitate the subsequent processing of related words, a phenomenon called masked priming. It has been debated whether masked primes can activate cognitive processes without gaining access to consciousness. Here we use a combination of behavioural and brain-imaging techniques to estimate the depth of processing of masked numerical primes. Our results indicate that masked stimuli have a measurable influence on electrical and haemodynamic measures of brain activity. When subjects engage in an overt semantic comparison task with a clearly visible target numeral, measures of covert motor activity indicate that they also unconsciously apply the task instructions to an unseen masked numeral. A stream of perceptual, semantic and motor processes can therefore occur without awareness.  相似文献   
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Individualization of acute postoperative pain treatment on an evidence-based decision process is a major health concern. The aim of this study is to investigate the influence of genetic and non-genetic factors on the variability of response to morphine in acute postoperative pain. A group of nighty-five patients undergoing major surgery were included prospectively. At 24 h, a logistic regression model was carried out to determine the factors associated with morphine doses given by a Patient Controlled Analgesia device. The dose of morphine was associated with age (p = 0.011), patient weight (p = 0.025) and the duration of operation (p = 0.030). This dose decreased with patient’s age and duration of operation and increased with patient’s weight. OPRM1 and ABCB1 polymorphisms were significantly associated with administered dose of morphine (p = 0.038 and 0.012 respectively). Patients with at least one G allele for c.118A>G OPRM1 polymorphism (AG/GG) needed 4 times the dose of morphine of AA patients. Additionally, patients with ABCB1 CT and CC genotypes for c.3435C>T polymorphism were 5.6 to 7.1 times more prone to receive higher dose of morphine than TT patients. Our preliminary results support the evidence that OPRM1/ABCB1 genotypes along with age, weight and duration of operation have an impact on morphine consumption for acute postoperative pain treatment.  相似文献   
100.
Fuzzy semantic model (FSM) is a data model that uses basic concepts of semantic modeling and supports handling fuzziness, uncertainty and imprecision of real-world at the attribute, entity and class levels. The paper presents the principles and constructs of the FSM. It proposes ways to define the membership functions within all the constructs of the FSM. In addition, it provides a proposal for specifying FSM schema and introduce a query language adapted to FSM-based databases.  相似文献   
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