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排序方式: 共有552条查询结果,搜索用时 15 毫秒
1.
Tadeusz Zając Agnieszka Klimek-Kopyra Ryszard Mazurek Andrzej Oleksy Jacek Strojny 《Journal of Natural Fibers》2020,17(8):1199-1211
ABSTRACT Nine sowing densities of linseed were compared in a two-year experiment. Self-regulation of the density of a linseed stand resulted in a differentiated branching of the plants. The number of capsules on a linseed shoot, as well as seeds in the capsule, and the number of seeds from the shoot were highly varied from year to year, and there is even a stronger differentiation in the weight of 1000 seeds. Linear relationships were noted between the mass of seeds from the linseed plant and the number of capsules. The yield of linseed was affected by both factors. An increasing sowing rate reduced the seed yield from the shoot and the plant. At lower seeding rates, the lateral shoots contributed in the seeds yield of the plant to a higher degree compared to the main ones. 相似文献
2.
The present study presents the synthesis of unsaturated polyester resins using only one glycol i.e., ethylene glycol. Polyesters of inorganic solubility in styrene were prepared. Properties of the resins in the noncrosslinked state in the process of crosslinking and after curing were studied. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3143–3150, 2006 相似文献
3.
Henrik Pettersson Tadeusz Gruszecki Lars-Henrik Johansson Per Johander 《Solar Energy Materials & Solar Cells》2003,77(4):6595
A manufacturing technique for monolithic dye-sensitised solar cells is presented. Encapsulated modules designed for indoor low-power applications have been prepared using industrial methods and equipment. Under certain conditions (light intensity <5000 lx, temperature between –10°C and 50°C, and relative humidity of appr. 50%), the modules have performed well and shown excellent long-term stability. Moreover, modules withstand illumination in combination with storage at 100% relative humidity. However, a certain degradation of the module performance takes place at illuminations exceeding 5000 lx and temperatures exceeding 50°C. 相似文献
4.
The cognitive exhaustion model of helplessness (predicting withdrawal from constructive effortful processing after uncontrollability) was applied to decision making. After unsolvable problems (or no preexposure), Ss requested information from a matrix with 5 alternatives (films)?×?10 attributes and then chose the best film. Films in a set were either similar (difficult decision) or dissimilar (easy decision) in attractiveness. As predicted, Ss with an uncontrollable preexposure spent less time on predecisional information search, disregarded their own importance criteria when asking for information, and had attention highly focused on a selected option for the easy decision condition but diffused across options for the difficult decision condition. The implications of these findings for understanding cognitive mechanisms of learned helplessness and depression are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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7.
Tadeusz Aniszewski 《Journal of the science of food and agriculture》1993,61(4):409-421
Abstract : An alkaloid-poor line of Washington lupin (Lupinus polyphyllus Lindl var SF/TA) was developed in an experiment started in 1982. The nutritive quality (alkaloid content, protein and amino acids, fat and fatty acids. macro- and micronutrients, fibre, sugars) yields, and seed quality of this line were studied. The results show that the total alkaloid content was low and varied in different seeds from 226 μg g?1 to 366 μg g?1 of dry matter. The main alkaloid was lupanine, but 16 other alkaloids (including sparteine and gramine) were also present. The var SF/TA cannot yet be used for human nutrition without processing although it would be a valuable protein crop. The results confirm that seeds which look different also vary in chemical composition. 相似文献
8.
Tadeusz Antczak 《Calcolo》2014,51(3):393-421
In this paper, Mond-Weir and Wolfe type duals for multiobjective variational control problems are formulated. Several duality theorems are established relating efficient solutions of the primal and dual multiobjective variational control problems under \((\Phi , \rho )\) -invexity. The results generalize a number of duality results previously established for multiobjective variational control problems under other generalized convexity assumptions. 相似文献
9.
Thin films, in the range of tens of micrometers thickness, have been prepared by casting onto glass plates the chloroform or N‐methylpyrrolidone solutions of polyimides or poly(imide‐amide)s containing silicon and phenylquinoxaline units in the main chain. The polymers have been synthesized by solution polycondensation reaction of aromatic diamines having preformed phenylquinoxaline rings with bis(3,4‐dicarboxyphenyl)dimethylsilane dianhydride or with a diacid chloride resulting from the reaction of this dianhydride with p‐aminobenzoic acid. The polymers were easily soluble in polar aprotic solvents and showed high thermal stability. The free‐standing films exhibited good mechanical properties with tensile strengths in the range of 48–86 MPa, tensile modulus in the range of 1.25–2.22 GPa and elongation at break in the range of 3–37%. Electrical insulating properties of some polymer films were evaluated on the basis of dielectric constant and dielectric loss and their variation with frequency and temperature. The values of the dielectric constant at 10 kHz were in the range of 2.94–3.08 for polyimides and 3.89–4.49 for poly(imide‐amide)s. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3062–3068, 2006 相似文献
10.
Adsorption of CO onto dehydrated cobalt-exchanged ZSM-5 zeolite was studied by CW-EPR techniques. It is shown that the reversible formation of a low spin carbonyl 1{Co(CO)
n
}7 adduct upon addition of carbon monoxide at p
CO>50–60 Torr involves significant change in the spin state of Co2+ from S=3/2 to 1/2. The spin Hamiltonian parameters of the adduct g
x
=2.222, g
y
=2.184, g
z
=2.011, |A
x
|=3.8 mT, |A
y
|=3.2 mT, |A
z
|=7.9 mT were determined by a computer simulation and further discussed in terms of the possible ground state and molecular structure. It is shown that the 1{Co(CO)
n
}7 cage complex exhibits a C2v symmetry with |z
2,2A1 ground state. 相似文献