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51.
Winter wheat is the most important cereal in Uzbekistan. Although the processing industry recognizes the low quality of local wheat, the present land use policy prioritizes production quantity, and wheat of better quality is imported to improve local flour. Yet, with increasing world market prices, Uzbekistan has to decide whether to continue allocating considerable resources for imports or to start investing in local quality improvements. This study therefore analyzed wheat production in the Khorezm region of Uzbekistan by (a) assessing the economic feasibility of local production vs. imports; and by (b) evaluating the current N-fertilizer management at field level in order to identify options for improving quality. Demand for wheat in the region currently falls short of supply by 79,000 t but under favorable world market prices, funds for importing additional wheat could be covered by cotton sales. Prices above $148 USD t−1 support the present land use policy to cultivate wheat but the baking quality of the crop is low. Higher N rates and/or an additional application of N at anthesis significantly increased grain quality. Additional costs for changes in N management, however, are currently not compensated by the price premiums at the State mills. Thus, in the absence of price incentives, it is unrealistic to expect producers to maximize quality production. Consequently, administrators must give quality greater attention by creating incentives through price differentials for higher quality, and encouraging awareness programs on wheat quality and improved on-field N management.  相似文献   
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Aiming at the development of a low‐cost technology for multipurpose water and surface treatment in the chemical industry and beyond, using microbubbles, a novel scheme of liquid‐gas interaction within a specially designed bubble generator was tested. Its efficiency for the production of microbubbles with a size distribution in the micron range is confirmed. The basic element of the device is a vortex chamber with water supply through tangential ducts, while the gas (air) is introduced in a highly turbulent swirling flow of water in radial direction through the orifice in the gas supply duct, located on the chamber axis. Bubble diameters, bubble velocities in the pipe flow and effect of the output pressure on the bubble size distribution were studied.  相似文献   
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BACKGROUND: Ozone is applied in wastewater treatment for effluent water quality improvement (post‐ozonation) as well as for excess sludge reduction (in the recirculation line). There is some evidence that ozone dosed directly to aerobic biooxidation (ABO) process enhances degradation of recalcitrant compounds into intermediates, following their biodegradation in the same reactor. However, no information regarding the influence of ozone on sludge yield in this system was found. Therefore, the current work aimed to evaluate the effect of ozone on the sludge yield when ozone is dosed directly to the ABO process. In addition, batch and continuous treatment schemes for phenolic wastewater treatment are compared. RESULTS: The results revealed that an optimal ozone dose of ~30 mgO3 L?1 day?1 reduced the sludge yield by ~50%, while effluent water quality in terms of total chemical oxygen demand (TCOD), compared with a conventional ABO process, was improved by 35.5 ± 3.6%. Slight improvement in soluble COD removal at the same ozone dose was also detected. The toxicity of effluent water was reduced as the ozone dose was increased. CONCLUSIONS: In an integrated ozonation‐ABO process it is possible to simultaneously reduce sludge yield and to improve effluent water quality, as COD and toxicity are reduced. Copyright © 2011 Society of Chemical Industry  相似文献   
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ABSTRACT

The review summarizes diverse knowledge about the problem of Linum usitatissimum L. response on photoperiod. Within this species, high genetic variability of the photosensitivity degree and influence of photoperiod on different plants characters were discovered. It was shown that in flax, earliness of flowering in long daylight is not strictly related to the low photosensitivity, and late genotypes with low photosensitivity can be found. In short daylight, various plant characters of different genotypes can be stable or display different reactions: increase or decrease their values. Also, the degree of photosensitivity does not have stable correlations with agronomic characters.  相似文献   
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Mental simulation provides a window on the future by enabling people to envision possibilities and develop plans for bringing those possibilities about. In moving oneself from a current situation toward an envisioned future one, the anticipation and management of emotions and the initiation and maintenance of problem-solving activities are fundamental tasks. In the program of research described in this article, mental simulation of the process for reaching a goal or of the dynamics of an unfolding stressful event produced progress in achieving those goals or resolving those events. Envisioning successful completion of a goal or resolution of a stressor—recommendations derived from the self-help literature—did not. Discussion centers on the characteristics of effective and ineffective mental simulations and their relation to self-regulatory processes. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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Given the reputation that psychoanalytic theory is biased against women, this study investigated 2 questions: (a) How common is it that empirical studies of psychoanalytic theory use male as opposed to female participants? and (b) What is the success rate in predicting women's and men's behavior? The empirical study of psychoanalytic hypotheses is apparently a predominantly male endeavor involving predominantly male participants. A meta-analysis of 98 relevant articles demonstrated that studies using both genders reported stronger results with men than women. However, studies using one gender only reported comparable results for men and women. Author gender, date of publication, and type of outcome measure used were unrelated to outcome. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The correlation between chemical effects of some typical optical fiber coating formulations and adhesion to glass was studied by the use of laser spallation. The technique was able to show verifiable differences between dissimilar materials and demonstrated a good correlation to adhesion values determined by mechanical peel testing, and to pullout values measured on coated optical fiber. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2459–2468, 2004  相似文献   
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