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1.
Agricultural by-products are becoming an attractive substrate for bioethanol production. The aim of this study was to evaluate the effects of regional differences in the rice hulls using Escherichia coli KO11 for bioethanol production. The rice hulls coded Edirne were obtained from Thrace Region, and the rice hulls coded Izmir were obtained from Aegean Region in Turkey. Rice hulls were treated by dilute acid before using them as substrates. The cells were incubated on an orbital shaker at 160 rpm under 30 °C during 96 h of the fermentation period. It was found that the maximum yield of ethanol from sugar (0.44 g ethanol/g reducing sugar) was obtained with the substrate C/N ratio of 29.16 in Izmir medium. The main difference was the dominant carbon source available as a substrate. It was detected that glucose concentration was about 2.5 times higher in Izmir medium, whereas xylose concentration was about two times higher in Edirne medium. The different results obtained with rice hulls from different origins could depend on the type of paddy as well as different cultivation conditions. These findings provide a valuable indicator for identifying suitable agricultural waste materials to be used as substrates for bioethanol production.  相似文献   
2.
The objectives of the present study on the growth of Haematococcus pluvialis were to indicate the effects of a long-term semi-continuous cultivation, sterilization, carbon dioxide, and different culture media by using artesian well water. This investigation was an enterprise in order to commercialize the production economically. When the effect of CO2 was investigated in basal culture medium, the influence of sterilization was also researched in Rudic’s culture medium in vertical panel-type photobioreactors for 31 days of semi-continuous cultivation. The maximum cell concentration of 10.55?×?105 cells ml?1, which corresponds to the growth rate of 0.271 day?1 with the areal productivity of 3.531 g m?2 day?1, was found in non-sterilized RM medium on the 24th day of the third run of semi-continuous cultivation at a renewal rate of 50% in a vertical panel-type photobioreactor.  相似文献   
3.
In this paper, we introduce one-parameter homothetic motions in the generalized complex number plane (\({\mathfrak{p}}\)-complex plane)
$$\mathbb{C}_{J}=\left\{x+Jy:\,\,\, x,y \in \mathbb{R},\quad J^2=\mathfrak{p},\quad \mathfrak{p} \in \{-1,0,1\} \right\} \subset \mathbb{C}_\mathfrak{p}$$
where
$$\mathbb{C}_\mathfrak{p}=\{x+Jy:\,\,\, x,y \in \mathbb{R}, \quad J^2=\mathfrak{p}\}$$
such that \({-\infty < \mathfrak{p} < \infty}\). The velocities, accelerations and pole points of the motion are analysed. Moreover, three generalized complex number planes, of which two are moving and the other one is fixed, are considered and a canonical relative system for one-parameter planar homothetic motion in \({\mathbb{C}_{J}}\) is defined. Euler-Savary formula, which gives the relationship between the curvatures of trajectory curves, during the one-parameter homothetic motions, is obtained with the aim of this canonical relative system.
  相似文献   
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5.
An HPLC method has been described in the European Pharmacopoeia and United States Pharmacopeia for the determination of nine organic impurities (imp A–I) in fingolimod hydrochloride, a synthetic sphingosine-1-phosphate receptor modulator. The manufacturing process of fingolimod hydrochloride consists of multistep chemical synthesis wherein controls of precursors, intermediates and process steps should be performed to assure the final quality of the drug substance. We synthesized and isolated eight process-related impurities (FINI imp A–H) of fingolimod, which were different from the pharmacopoeial impurities. One unknown process-related impurity was found as a key intermediate (FINI) and was identified by LC–MS. Characterization of all of the impurities were done using spectroscopic techniques (1H and 13C NMR, FTIR, MS), and the mechanistic pathways to the formation of these impurities were also discussed. Two of these impurities were evaluated as potential genotoxic impurities owing to their alerting structures and alkylating properties (alkyl sulfonates and alkyl halides, class 3, ICH M7). We also developed and validated an RP-UPLC method in line with ICH Q2 guidelines for control these impurities (FINI imp A–H) and to assure the pharmacopoeial quality drug substance.  相似文献   
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7.
In this paper, water flow in a rib-roughened channel is investigated numerically by using Reynolds stress turbulence models (RSM) on a three-dimensional (3-D) domain. Computational results for mean streamwise velocity component and turbulent kinetic energy show good agreements with available experimental data. Five rib pitch-to-height ratios (p/h) of 1, 5, 10, 15 and 20 are analysed for six different Reynolds numbers (Re) of 3000, 7000, 12,000, 20,000, 40,000 and 65,000. Velocity vectors, streamlines and Reynolds stresses are showed for these ratios and Re numbers. Streamlines revealed that Reynolds numbers do not affect flowfield but play an important role in the Reynolds stresses.  相似文献   
8.
Vehicle refinishing body shops are concerned by the environmental policy against photochemical air pollution caused by VOC emissions. For supporting these small enterprises the mass and energy flow model IMPROVE has been developed. Based on an LCA-approach, the process steps of vehicle refinishing are modelled. The model IMPROVE helps to disseminate the consequences of product substitution in comparison to so far used products and techniques in the body shop. For the dissemination of experiences practical guidelines have been developed. Moreover, a comprehensible tool for the Solvent Balance is being offered. Thus, various means are available for consulting and also for strategic production planning for the SME in the sector.  相似文献   
9.
The purpose of the current study was to characterize Leishmania cell-surface antigens by two different methods established for the purification of glycoproteins and proteins, and to point out a useful approach to define their size and mass heterogeneity. L. tropica parasites were initially isolated from patients with active cutaneous leishmaniasis and were then cultured in vitro. The parasite-cell layer was solubilised with 6 M guanidinium chloride (GuHCl) and subsequently prepared for the purification procedure. The methods used in this work were gel filtration chromatography and isopycnic density-gradient centrifugation. Because of the presence of a substantial amount of non-specific proteins in the culture medium, these methods were not effective alone in distinguishing these antigens. However, a good idea of their N-glycosylated structures could be obtained by using Periodic acid-Schiffs (PAS) and Con A lectin, and also size and mass heterogeneity. A combination of these methods effected a clear separation of the antigens. Amino acid analysis of the purified antigens was performed to positively identify them as well-known Leishmania cell-surface antigen gene products. The results confirmed the presence of more than one cell-surface antigen on the Leishmania parasite and the combination of gel chromatography and density-gradient centrifugation could be useful for their isolation.  相似文献   
10.
We consider the problem of efficiently managing a fishery where pollution externalities are present. The open‐access bionomic model is analyzed in an ‐player differential game framework with two‐state variables, that is, the fish stock and the pollution stock. We characterize the noncooperative feedback‐Nash equilibrium and cooperative solution, and define an egalitarian sharing rule to allocate the joint welfare maximizing payoff over an infinite time horizon, and show that this rule is time consistent. Recommendations for Resource Managers
  • ● Cooperation in management of a fishery where pollution externalities are present yields a higher payoff over time as compared to the noncooperative behavior.
  • ● The dividend of cooperation can be allocated among the fisherpersons according to an egalitarian sharing rule.
  • ● This allocation is time‐consistent, that is, no player will be tempted to deviate from cooperation as time goes by, and the initial agreement is sustainable.
  相似文献   
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