Nutritionally important chemical constituents and yield of carrot (Daucus carota L.) roots grown organically using ten levels of green manure. Accepted February 27, 2002. Acta Agric. Scand., Sect. B, Soil and Plant Sci. 51: 125 -136, 2001. © 2002 Taylor & Francis.In a eld experiment carried out over two years (1995, 1996) carrots were grown organically on a sandy loam soil. A broad range of mineral nitrogen (N-min) levels at carrot emergence was obtained by depleting or amending the soil by removing or supplying different amounts of green manure. With N-min values ranging from 22 to 162 kg N ha ¼ 1 at carrot emergence, the N uptake of the carrot crop increased linearly from 70 to 200 kg N ha ¼ 1 . The yield increased with N-min at lower levels of N, but levelled off above 90 -100 kg N ha ¼ 1 . In fresh carrot roots the concentrations of total N, ten individual amino acids, total sum of amino acids, two amides, asparagine and glutamine, and b-carotene increased linearly with the soil concentration of N-min at carrot emergence. Nitrate N increased exponentially with N-min, reaching levels of 340 mg NO 3 kg ¼ 1 fresh weight under some conditions. The concentrations of potassium, calcium, glucose, fructose, sucrose and six individual free amino acids were unaffected by the N-min level. Magnesium was decreased at the lowest deliberately depleted N-min levels, whereas the concentration of dry matter and vitamin C decreased linearly with increasing N-min levels. Signi cantly lower concentrations of dry matter, total N, nitrate N, vitamin C and total sum of free amino acids were found in the warm and sunny year 1995 with the highest yield of carrot roots, whereas the contrary was found for b-carotene.

Wind turbine rotor blades are commonly manufactured from composite materials by a moulding process. Typically, the wind turbine blade is produced in two halves, which are eventually adhesively joined along their edges. Investigations of operating wind turbine blades show that debonding of the trailing edge joint is a common failure type, and information on specific reasons is scarce. This paper is concerned with the estimation of the strain energy release rates (SERRs) in trailing edges of wind turbine blades in order to gain insight into the driving failure mechanisms. A method based on the virtual crack closure technique (VCCT) is proposed, which can be used to identify critical areas in the adhesive joint of a trailing edge. The paper gives an overview of methods applicable for fracture cases comprising non‐parallel crack faces in the realm of linear fracture mechanics. Furthermore, the VCCT is discussed in detail and validated against numerical analyses in 2D and 3D. Finally, the SERR of a typical blade section subjected to various loading conditions is investigated and assessed in order to identify potential design drivers for trailing edge details. Analysis of the blade section model suggests that mode III action is governing and accordingly that flapwise shear and torsion are the most important load cases.Copyright © 2013 John Wiley & Sons, Ltd.

The utility of low‐frequency ultrasonics in evaluating the viscoelastic properties of dough from different biscuit wheat flour qualities was studied. No distinct correlation was found between the ultrasonic characteristic (ultrasound velocity, v) and the rheological characteristics storage modulus, G' (r=0.43), or loss modulus, G″ (r=0.61), when a constant amount of water was added to the dough. Fairly high correlations were obtained between the ultrasound velocity, v, and the rheological measurements G' (r=0.93), G″ (r=0.92) and the phase angle G′ (r=0.81) with variable addition of water, corresponding to the water absorption capacity of the dough. It was not possible to distinguish between hard and soft endosperm biscuit wheat varieties using ultrasonic measurements, whether with a constant or a variable amount of water added. A high negative correlation was obtained between ultrasonic measurements and the amount of water added to the dough (r = ‐0.94), indicating that the amount of water added affected the ultrasonic measurements more significantly than differences in dough structure and rheological properties. The effect of ageing on the ultrasonic characteristics of dough samples was also studied. The ultrasound velocity, v, and storage modulus, G', increased during 40 min ageing. A high correlation obtained between ultrasound velocity, v, and the storage modulus, G' (r=0.97), indicates that ultrasonics may be a valid method of process control of rheological properties during the manufacture of dough.

The effect of uniaxial compression rate (20–1000 mm/min) on the parameters: Stress (σftrue), strain (εfHencky) and work to fracture (Wf), modulus of deformability (Ed), maximum slope before fracture (Emax) and work during 75% compression (Wtotal) was investigated for ten potato varieties. Multivariate data analysis was used to study the correlation between and within the sensory and nonsensory measurements by Principal Component Analysis (PCA) which showed σftrue, Emax, Wf, and Wtotal to explain the same type of information in the data, and εfHencky versus Ed another type of information in the data. The deformation rate had a large effect on εfHencky. Nine sensory texture attributes covering the mechanical, geometrical and moistness attributes were evaluated. Relationships between uniaxial compression data at various deformation rates and the sensory texture attributes were studied by Partial Least Squares Regression (PLSR). A minor effect of deformation rate on the correlation with the sensory texture properties was obtained. Mechanical properties were predicted to a higher extent than the geometrical attributes and moistness. The prediction of the mechanical, geometrical and moistness attributes increased largely by using uniaxial compression supplemented by chemical measures such as dry matter and pectin methylesterase, but here no relevant effect of deformation rate was obtained.

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