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11.
An optimal pump operation schedule that maintains satisfactory hydraulics conditions can generally reduce energy consumptions compared to the traditional trial and error based pump operation schedule. Linking an evolutionary based optimization algorithm with a hydraulic simulation model has gained attention for obtaining the optimal schedule. However, this technique requires significant computation time and thus has difficulty in real-time implementation. This paper presents several tactics to generate warm solutions that can be used in the initial population of the evolutionary algorithms to reduce the computation times. Strategies to generate warm solutions include the use of linear programming, surrogate model known as machine learning or meta-model, and historical pump schedule for similar demand pattern. Providing warm solutions from approximate methods or previous day’s results to stochastic search methods can improve solution convergence and offers significant computation time benefits. Results obtained from different strategies are compared. 相似文献
12.
Synthesis and nuclear magnetic resonance properties of all geometrical isomers of conjugated linoleic acids 总被引:1,自引:0,他引:1
Pure geometric isomers of conjugated linoleic acid were prepared from castor oil as the primary starting material. Methyl
octadeca-9Z, 11E-dienoate (2) and methyl octadeca-9Z, 11Z-dienoate (4) were obtained by zinc reduction of methyl santalbate (1, methyl octadec-11E-en-9-ynoate) and methyl octadec-11 Z-en-9-ynoate (3), respectively, as the key intermediates. Methyl octadeca-9E, 11E-dienoate (8) and methyl octadeca-9E, 11Z-dienoate (9) were prepared by demesylation of the mesyloxy derivative of methyl ricinelaidate (6, methyl 12-hydroxy-octadec-9 E-enoate). A study of the nuclear magnetic resonance spectral properties was carried out and the shifts of the olefinic carbon
atoms of 18:2(9Z, 11E) (2) and 18:2(9E, 11Z) (9) were readily identified by a combination of incredible natural abundance double quantum transfer experiment, heteronuclear
multiple bond correlation, and 1H−13C correlation spectroscopy correlation techniques. Doubts remain in the absolute identification of the individual olefinic
carbon atoms of the 18:2(9Z, 11Z) (4) and 18:2(9E, 11E) (8), except the fact that the shifts of the “inner” (C-10 and C-11) and “outer” (C-9 and C-12) positioned olefinic carbon atoms
of the conjugated diene system are distinguishable. 相似文献
13.
Wheat gluten: high molecular weight glutenin subunits--structure, genetics, and relation to dough elasticity 总被引:2,自引:0,他引:2
ABSTRACT: Gluten proteins, representing the major protein fraction of the starchy endosperm, are predominantly responsible for the unique position of wheat amongst cereals. These form a continuous proteinaceous matrix in the cells of the mature dry grain and form a continuous viscoelastic network during the mixing process of dough development. These viscoelastic properties underline the utilization of wheat to prepare bread and other wheat flour based foodstuffs. One group of gluten proteins is glutenin, which consists of high molecular weight (HMW) and low molecular weight (LMW) subunits. The HMW glutenin subunits (HMW-GS) are particularly important for determining dough elasticity. The common wheat possesses 3 to 5 HMW subunits encoded at the Glu-1 loci on the long arms of group 1 chromosomes (1A, 1B, and 1D). The presence of certain HMW subunits is positively correlated with good bread-making quality. Glutamine-rich repetitive sequences that comprise the central part of the HMW subunits are actually responsible for the elastic properties due to extensive arrays of interchain hydrogen bonds. Genetic engineering can be used to manipulate the amount and composition of the HMW subunits, leading to either increased dough strength or more drastic changes in gluten structure and properties. 相似文献
14.
Farhan Saeed Imran Pasha Muhammad Umair Arshad Faqir Muhammad Anjum Shahzad Hussain Rizwan Rasheed 《International Journal of Food Properties》2013,16(9):1895-1904
Functional and nutraceutical foods have captured the global market owing to trends and perceptions of consumers on the natural products and diet-health linkages. Health promoting potential of such foods has been attributed to the presence of essential bioactive moieties. Wheat, being staple food in many parts of the world, gained substantial attention of researchers particularly for the extraction of various functional components. Among these, fructan oligosaccharides in nature bestow quality of baked products and provide protection against various physiological disorders. Addition of fructan in various baked products enhances softness and color, especially in bread, and also imparts textural improvement. Moreover, fructans boost mineral absorption, hypocholesterolemic, and hypoglycemic perspectives, bifidogenic nature and controlling cancer insurgence. The benefits allied with fructan are mainly dose and time dependent. In this context, its industrial applications for vulnerable groups are increasing worldwide. 相似文献
15.
ST O'Sullivan M O'Sullivan N Pasha M O'Shaughnessy TP O'Connor 《Canadian Metallurgical Quarterly》1997,28(9-10):639-642
The patient with severe lower limb trauma presents a management dilemma; whether to amputate primarily or to attempt limb salvage. In recent years, many predictive indices have been published which purport to identify limbs which are non-viable. We retrospectively applied two recently described indices, the Mangled Extremity Severity Score (MESS) and the Limb Salvage Index (LSI), to 54 limbs in 50 patients with either Gustilo IIIB or IIIC complex tibial fractures. There were 22 amputations (40.7 per cent) in the series. The mean MESS score in the limb salvage group was 3.8 (range 2-10), and the mean MESS score in the amputation group was 7.7 (range 4-13) (P < 0.0001). The mean LSI score in the limb salvage group was 3.6 (range 3-8), and the mean LSI score in the amputation group was 6.9 (P < 0.01). However, in the group with MESS scores > 7 (which recommends amputation), there were three limbs which were salvaged with acceptable functional outcome. Similarly, in those with LSI scores > 6 (which recommends amputation), there were seven limbs successfully salvaged. A MESS > 7 offered a greater relative risk of amputation (9.2) than a LSI score > 6 (5.3). We found both indices of use in predicting limb salvage and functional outcome. However, neither is sufficiently accurate to be considered absolutely reliable in clinical practice. 相似文献
16.
A small survey confirms that epidural infusions are often prepared by clinicians and solutions may be changed each day because of fears of microbiological contamination. We have assessed the microbiological safety of six mixtures of diamorphine (0.01-1.0%) and bupivacaine (0.1-0.5%) representing the spectrum of clinically useful concentrations for use as extradural infusions. The solutions were studied for antibacterial activity against common contaminants of fluids: Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis and a coagulase negative Staphylococcus sp. A saline control was included. Challenge experiments used an inoculum of approximately 5.0 x 10(6) cfu/ml. Mixtures were incubated at 30 degrees C for up to 7 days. Viable counts of all organisms decreased with time for all the formulations tested. Formulations containing 0.5% bupivacaine were rapidly bactericidal, and increasing diamorphine concentrations increased this effect. Formulations with 0.5% bupivacaine had more activity than those with 0.1% bupivacaine. Mixtures of diamorphine and bupivacaine in concentrations used clinically have bactericidal activity against commonly encountered skin organisms. The common practice of changing every day epidural infusions containing these drugs is unnecessary. 相似文献
17.
Lindane suppressed both primary and secondary antibody responses to sheep red blood cell (SRBC) in albino mice, the effects being more pronounced on the secondary than the primary response. However, a longer duration of pesticide exposure induced similar degrees of immunosuppression on both responses. The sequential study of plaque forming cells (PFC) kinetics revealed that suppression of plaque formation not only occurred at peak days but also on pre and post peak days, and there was no delay in peak antibody formation. Moreover, reduction in the primary PFC was not associated with decrease in the antibody response to SRBC. The results indicate that lindane suppresses both primary and secondary humoral immune responses in a time and dose dependent manner, and suggest a threshold susceptibility to exposure. 相似文献
18.
Photochemical reactions of polyene sequences produced during the degradation of poly(vinyl chloride)
Photosensitized reactions of tetrahydrofuran (THF) and dichloromethane (DCM) solutions of polyene sequences introduced into poly(vinyl chloride) molecules by chemical degradation have been investigated. The distribution of polyenes produced following further thermal degradation in DCM were shifted toward longer sequences than were observed for the same reaction in THF. Benzophenone-sensitized bleaching of the polyene absorption in aerated THF solutions was characterized by induction periods, but the presence of oxygen had little effect on the same reaction in DCM. The bleaching process seems to involve reaction of the polyenes with the tetrahydrofuranyl radical formed by abstraction of the α-hydrogen from THF by triplet benzophenone. No induction periods were observed for benzoin-sensitized reactions, but the rate of reaction was faster in DCM than in THF. The differences are discussed in terms of the difference in reactivity of the alkyl and alkoxy radicals. 相似文献
19.
Haris Mahmood Khan Chaudhry Haider Ali Tanveer Iqbal Saima Yasin Muhammad Sulaiman Hamayoun Mahmood Muhammad Raashid Mohsin Pasha Bozhong Mu 《中国化学工程学报》2019,27(10):2238-2250
Biodiesel utilization has been rapidly growing worldwide as the prime alternative to petrodiesel due to a global rise in diesel fuel demand along with hazardous emissions during its thermochemical conversion. Although, several debatable issues including feedstock availability and price, fuel and food competition, changes in land use and greenhouse gas emission have been raised by using edible as well as inedible feedstocks for the production of biodiesel. However, non-crop feedstocks could be a promising alternative. In this article, waste cooking oils have been recommended as a suitable option for biodiesel production bearing in mind the current national situation. The important factors such as the quantity of waste cooking oil produced, crude oil and vegetable oil import expenses, high-speed diesel imports, waste management issues and environmental hazards are considered. Moreover, process simulation and operating cost evaluation of an acid catalyzed biodiesel production unit are also conducted. The simulation results show that the production cost of waste cooking oil-based biodiesel is about 0.66USD·L-1. We believe that the present overview would open new pathways and ideas for the development of biofuels from waste to energy approach in Pakistan. 相似文献
20.
Baig-Ansari N Badruddin SH Karmaliani R Harris H Jehan I Pasha O Moss N McClure EM Goldenberg RL 《Food and nutrition bulletin》2008,29(2):132-139
BACKGROUND: Anemia affects almost two-thirds of pregnant women in developing countries and contributes to maternal morbidity and mortality and to low birthweight. OBJECTIVE: To determine the prevalence of anemia and the dietary and socioeconomic factors associated with anemia in pregnant women living in an urban community setting in Hyderabad, Pakistan. METHODS: This was a prospective, observational study of 1,369 pregnant women enrolled at 20 to 26 weeks of gestation and followed to 6 weeks postpartum. A blood sample was obtained at enrollment to determine hemoglobin levels. Information on nutritional knowledge, attitudes, and practice and dietary history regarding usual food intake before and during pregnancy were obtained by trained interviewers within 1 week of enrollment. RESULTS: The prevalence of anemia (defined by the World Health Organization as hemoglobin < 11.0 g/dL) in these subjects was 90.5%; of these, 75.0% had mild anemia (hemoglobin from 9.0 to 10.9 g/dL) and 14.8% had moderate anemia (hemoglobin from 7.0 to 8.9 g/dL). Only 0.7% were severely anemic (hemoglobin < 7.0 g/ dL). Nonanemic women were significantly taller, weighed more, and had a higher body mass index. Multivariate analysis after adjustment for education, pregnancy history, iron supplementation, and height showed that drinking more than three cups of tea per day before pregnancy (adjusted prevalence odds ratio [aPOR], 3.2; 95% confidence interval [CI], 1.3 to 8.0), consumption of clay or dirt during pregnancy (aPOR, 3.7; 95% CI, 1.1 to 12.3), and never consuming eggs or consuming eggs less than twice a week during pregnancy (aPOR, 1.7; 95% CI, 1.1 to 2.5) were significantly associated with anemia. Consumption of red meat less than twice a week prior to pregnancy was marginally associated with anemia (aPOR, 1.2; 95% CI, 0.8 to 1.8) but was significantly associated with lower mean hemoglobin concentrations (9.9 vs. 10.0 g/dL, p = .05) during the study period. A subanalysis excluding women with mild anemia found similar associations to those of the main model, albeit even stronger. CONCLUSIONS: A high percentage of women at 20 to 26 weeks of pregnancy had mild to moderate anemia. Pica, tea consumption, and low intake of eggs and red meat were associated with anemia. Women of childbearing age should be provided nutritional education regarding food sources of iron, especially prior to becoming pregnant, and taught how food choices can either enhance or interfere with iron absorption. 相似文献