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1.
浅谈石油、化工油库的消防设计   总被引:2,自引:0,他引:2  
对石油、化工库消防系统设计中,的确定和选择,设计参数的选用、消防设备的选型和设置等问题做了较详尽的介绍。  相似文献   

2.
Inexpensive and rapid methods for measurement of seed oil content by near infrared reflectance spectroscopy (NIRS) are useful for developing new oil seed cultivars. Adopting default multiple linear regression (MLR), the predictions of safflower oil content were made by 20–140 samples using a Perten Inframatic 8620 NIR spectrometer. Although the obtained interpolation results of MLR had desired accuracy, the extrapolation was extremely poor. The extrapolation determination coefficient (R2) and standard error (SE) of cross validation for MLR models were 0.63–0.78 and 3.71–4.44, respectively. In order to overcome the accuracy limitation of linear MLR models, a common suggestion is to use a nonlinear artificial neural network (ANN); however, it needs a large number of data to yield significant accurate results. We developed a novel robust hybrid fuzzy linear neural (HFLN) network to capture simultaneously linear and nonlinear patterns of data with a limited number of safflower samples. Empirical extrapolation results showed that the HFLN had higher R2 (=0.85) and lower SE (=1.83) compared to those obtained by MLR and ANN models. It is concluded that hybrid methodologies could be used to construct efficient and appropriate models for estimation of seed oil content set up on NIR system.  相似文献   

3.
Laboratory‐scale experiments were carried out for measuring the chord length distribution of different particle systems using a laser reflection sensor. Samples consisted of monodisperse, polydisperse and bimodal FCC catalyst and PVC particles of different sizes, ranging from about 20 to 500 μm. The particles were dispersed in water, forming suspensions with solid‐phase mass fractions ranging from ca. 0.2 % until ca. 30 %. The experimental results, consisting of the particle number counting per chord length class, were used in fitting a neural network model for estimating the mass concentration of particles in the suspension and the volume‐based size distribution, eliminating the effects of suspension concentration and particle shape. The results indicate the feasibility of using such a model as a software sensor in crystallization processes monitoring.  相似文献   

4.
The aim of this work is to study the effects of six operational variables, i.e., dissolved oxygen (DO), nitrate recirculation flow, sludge recycle flow, sludge wastage flow, external carbon dosage, and anoxic volume fraction, on the performance of nitrogen removal and its control in a pre‐denitrification plant. The results obtained show that the six operational variables have a significant influence on nitrogen removal in such a system, while the utilization of the control strategies can improve the situation to a significant extent. The control of DO concentration should be correlated with the influent ammonia load, the effluent requirement and nitrification type. The anoxic effluent nitrate concentration should be controlled at ca. 2 mg/L or the ORP value at the end of the anoxic zone should be controlled at ca. –90 mV. The control of the sludge recycling flow by online monitoring of the sludge blanket height (SBH), is an alternative to the conventional control of the constant sludge recycle flow. It may be possible to achieve the automatic control of sludge wastage flow by online measuring of the ammonia concentration and the nitrification capacity of the sludge. The recirculation of nitrate and external carbon dosage should be simultaneously controlled to optimize nitrogen removal. The anoxic volume fraction should also be optimized, to ensure a good balance between nitrification and denitrification.  相似文献   

5.
Polyurethane foams (PUFs) are widely used materials because of their wide range of applications, particularly, thermal and sound insulation, mattresses, furniture, construction, cushioning, packaging, transportation of goods, etc. Recently, commercial PUF products fabricated from plant oil (PO)‐based polyols have gained increasing popularity, because of their low cost and eco‐friendly nature in comparison to petroleum‐based PUF. To date, insufficient reviews have been reported in the area of modification of plant oils for synthesizing polyol for foam synthesis. Due to abundant availability, low‐cost, and renewable nature of plant oils, they are being used as precursors for modern polyurethane industry use. There is a need for versatile and economical methods for conversion of plant oils such as castor oil (CO) and soybean oil (SO) into useful polyols for industry use. This review is an overview of the most recent advanced methods for the conversion of plant oils into polyol and further utilization of it for commercial PUF products. Since the last decade, many researchers have shown that plant‐polyol‐derived PUF can compete with conventional PUF. Practical Applications: Practical applications of the PO‐based polyurethane foams include thermal insulation, sound insulation, packaging, and waste water treatment.  相似文献   

6.
Enormous efforts have been made to facilitate produced‐gas analyses by in situ combustion implication in heavy‐oil recovery processes. Robust intelligence‐based approaches such as artificial neural network (ANN) and hybrid methods were accomplished to monitor CO2/O2/CO. Implemented optimization approaches like particle swarm optimization (PSO) and hybrid approach focused on pinpointing accurate interconnection weights through the proposed ANN model. Solutions acquired from the developed approaches were compared with the pertinent experimental in situ combustion data samples. Implication of hybrid genetic algorithm and PSO in gas analysis estimation can lead to more reliable in situ combustion quality predictions, simulation design, and further plans of heavy‐oil recovery methods.  相似文献   

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How to prepare a hydrogel with high strength and excellent tearing fracture energy is a problem faced by researchers. Here, tough and tear‐resistant double‐network hydrogels (Cx‐SMy gels) are successfully prepared via a facile strategy: micellar polymerization followed by solution polymerization. The strength and fracture energy of these hydrogels are up to 13 MPa and 26500 J m?2, respectively, which are attributed to the synergy of quatra‐crosslinking interactions inside the double‐network. The quatra‐crosslinking interactions include hydrophobic interaction, crystallization, electrostatic attraction, and hydrogen bonding. Moreover, it is confirmed that the facile strategy is a general way to prepare tough hydrogels by using electrolytic monomers and hydrophobic acrylates.  相似文献   

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Canolol‐enriched extracts obtained from the extraction of fluidized bed treated canola meal with supercritical carbon dioxide were added to high‐oleic canola oil in different concentrations (200, 500 and 750 mg/kg). After 30 h of deep‐fat frying, oils fortified with canolol‐enriched extracts showed a two to three times better frying performance in comparison to the commonly used antioxidants (TBHQ, 200 mg/kg; rosemary extract, 40 and 200 mg/kg) and a control without antioxidants with regards to the formation of di‐ and polymer triacylglycerols, total polar compounds, secondary degradation products (anisidine value) and the iodine value. The canolol‐enriched extracts were also able to slow down the degradation of α‐ and γ‐tocopherol during frying resulting in significant amounts of tocopherols after 30 h of frying in comparison to the other oils. The influence of the canolol‐enriched extracts indicated strongly concentration‐dependent performance. With increasing concentration of the extract, the thermal stability of the fortified oil was improved. The only disadvantage of the addition of the extracts was an increase in the initial acid value, but within the frying time, only oil fortified with 750 mg canolol‐enriched extract/kg reached the limit given in different countries.  相似文献   

12.
Although widely occurring lipid oxidation, which is triggered by reactive oxygen species (ROS), produces a variety of oxidized lipids, practical methods to efficiently analyze oxidized lipids remain elusive. Herein, it is shown that the glycoblotting platform can be used to analyze oxidized lipids. Analysis is based on the principle that lipid aldehydes, one of the oxidized lipid species, can be captured selectively, enriched, and detected. Moreover, 3‐methyl‐1‐p‐tolyltriazene (MTT) methylates phosphoric and carboxylic acids, and this MTT‐mediated methylation is, in combination with conventional tandem mass spectrometry (MS/MS) analysis, an effective method for the structural analysis of oxidized lipids. By using three classes of standards, liposomes, and a lipoprotein, it is demonstrated that glycoblotting represents a powerful approach for focused lipidomics, even in complex macromolecules.  相似文献   

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A section of a carbon‐fiber‐reinforced composite horizontal stabilizer skin from a 737‐200 aircraft that had been in service for 20 years was analyzed with Fourier transform infrared spectroscopy and dynamic mechanical thermal analysis in an effort to determine the molecular changes that occurred in the epoxy matrix resin over the service life. Comparisons were made with a similar matrix resin system that had been aged under various accelerating conditions. As expected, the results showed that the molecular changes were slight and occurred only on the unpainted (internal) surface areas of the composite. The changes in the commercial materials during the in‐service aging were most similar to those in a composite that had been artificially aged at 120°C for 3000 h, but they included two chemical changes not seen previously. There was an increase in the number of aliphatic hydrocarbon molecules (a fuel chemical) as well as a decrease in the number of molecules containing ? SO2? units. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

15.
This work considers the problem of determining the transition of ethanol‐producing bio‐reactors from batch to continuous operation and subsequent control subject to constraints and performance considerations. To this end, a Lyapunov‐based non‐linear model predictive controller is utilized that stabilizes the bio‐reactor under continuous mode of operation. The key idea in the predictive controller is the formulation of appropriate stability constraints that allow an explicit characterization of the set of initial conditions from where feasibility of the optimization problem and hence closed‐loop stability is guaranteed. Additional constraints are incorporated in the predictive control design to expand on the set of initial conditions that can be stabilized by control designs that only require the value of the Lyapunov function to decay. Then, the explicit characterization of the set of stabilizable initial conditions is used in determining the appropriate time for which the reactor must be run in batch mode. Specifically, the predictive control approach is utilized in determining the appropriate batch length that achieves stabilizable values of the state variables at the end of the batch. Application of the proposed method to the ethanol production process using Zymomonas mobilis as the ethanol producing micro‐organism demonstrates the effectiveness of the proposed model predictive control strategy in stabilizing the bio‐reactor.  相似文献   

16.
Cyclohexylcarbamic acid aryl esters are a class of fatty acid amide hydrolase (FAAH) inhibitors, which includes the reference compound URB597. The reactivity of their carbamate fragment is involved in pharmacological activity and may affect their pharmacokinetic and toxicological properties. We conducted in vitro stability experiments in chemical and biological environments to investigate the structure–stability relationships in this class of compounds. The results show that electrophilicity of the carbamate influences chemical stability, as suggested by the relation between the rate constant of alkaline hydrolysis (log kpH9) and the energy of the lowest unoccupied molecular orbital (LUMO). Introduction of small electron‐donor substituents at conjugated positions of the O‐aryl moiety increased the overall hydrolytic stability of the carbamate group without affecting FAAH inhibitory potency, whereas peripheral non‐conjugated hydrophilic groups, which favor FAAH recognition, helped decrease oxidative metabolism in the liver.  相似文献   

17.
The growing awareness of the sugar code—i.e. the biological functionality of glycans—is leading to increased interest in lectins as drug targets. The aim of this study was to establish a strategic combination of screening procedures with increased biorelevance. As a model, we used a potent plant toxin (viscumin) and lactosides synthetically modified at the C6/C6′ positions and the reducing end aglycan. Changes in the saturation transfer difference (STD) in NMR spectroscopy, applied in inhibition assays, yielded evidence for ligand activity and affinity differences. Inhibitory potency was confirmed by the blocking of lectin binding to a glycoprotein‐bearing matrix. In cell‐based assays, iodo/azido‐substituted lactose derivatives were comparatively active. Interestingly, cell‐type dependence was observed, indicating the potential of synthetic carbohydrate derivative to interact with lectins in a cell‐type (glycan profile)‐specific manner. These results are relevent to research into human lectins, glycosciences, and beyond.  相似文献   

18.
In the present work, a new and simple Schiff base‐assisted extraction strategy for Ni and Zn from an edible oil matrix with subsequent determination using a flame atomic absorption spectrometer was suggested. According to the green approach, laborious sample‐pretreatment procedures were eliminated via complexation of the analytes with N,N′‐bis(4‐methoxysalycylidene)‐2‐hydroxy‐1,3‐propanediamine (4MSHP) and transferred from the oil phase to the aqueous phase. The complexation properties of 4MSHP, Ni, and Zn were investigated using UV–vis spectrophotometry. The experimental conditions that affect the extraction efficiency were optimized using central composite design. The optimum conditions for the extraction of Ni and Zn were as follows: a volume to oil mass ratio of 0.83 to 1.31 mL g?1 of 4MSHP solution; 62.3‐ and 50.6‐min, stirring time; 27.3 and 31.1 °C, temperature, respectively. The detection limits (3sbm?1) were 0.41 μg g?1 for Ni and 0.16 μg g?1 for Zn. Validation of the suggested work was performed by the analysis of organometallic standard‐doped n‐hexane solutions as certified reference materials under the optimum experimental conditions. The recovery percentages were warranted the accuracy and found as 98.2 ± 1.8% for Ni and 99.8 ± 1.2% for Zn. In addition, relative SD values were below 5% for both the analytes. The Student's t‐test showed that there was no significant difference between the found and doped amount of analytes at 95% confidence level. The features such as the detection technique, cheapness, eco‐friendly solvent usage, and practicality were better compared to the literature.  相似文献   

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An important way for the production of biodiesel is the base‐catalyzed transesterification of oil or fat with monohydric alcohols. Flow and reaction analysis with respect to the applicability of a micro/millireactor setup to two‐phase ethanolysis of waste cooking oil is described. The flow in the micro/millireactor system was examined on the example of a soybean oil/ethanol mixture and compared with a T‐mixer. Parallel and slug flow were observed in different reactor sections of the micro/milli‐reactor system and evaluated concerning their efficiency. A method for determination of the viscosity of the mixture was conducted and validated. Certain pretreatments were investigated with regard to the suitability of the waste cooking oil for ethanolysis. Relations between biodiesel yields and some oil properties like chain length and acid number were found.  相似文献   

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