Rotary cement kiln coating estimator: Integrated modelling of kiln with shell temperature measurement

Coating thickness protection in the burning zone of a rotary cement kiln during operation is important from the viewpoint of the kiln productivity. In this paper, an integrated model is presented to estimate the coating thickness in the burning zone of a rotary cement kiln by using measured process variables and scanned shell temperature. The model can simulate the variations of the system, thus the impact of different process variables and environmental conditions on the coating thickness can be analysed. The presented steady‐state model derived from heat and mass balance equations uses a plug flame model for simulation of gas and/or fuel oil burning. Moreover, the heat transfer value from shell to the outside is improved by a quasi‐dynamic method. Therefore, at first, the model predicts the inside temperature profile along the kiln, then by considering two resistant nodes between temperatures of the inside and outside, the latter measured by shell scanner, it estimates the formed coating thickness in the burning zone. The estimation of the model was studied for three measured data sets taken from a modern commercial cement kiln. The results confirm that the average absolute error for estimating the coating thickness for the cases 1, 2, and 3 are 3.26, 2.82, and 2.21 cm, respectively.     

The Potential of Adaptive Design in Animal Studies

Clinical trials are the backbone of medical research, and are often the last step in the development of new therapies for use in patients. Prior to human testing, however, preclinical studies using animal subjects are usually performed in order to provide initial data on the safety and effectiveness of prospective treatments. These studies can be costly and time consuming, and may also raise concerns about the ethical treatment of animals when potentially harmful procedures are involved. Adaptive design is a process by which the methods used in a study may be altered while it is being conducted in response to preliminary data or other new information. Adaptive design has been shown to be useful in reducing the time and costs associated with clinical trials, and may provide similar benefits in preclinical animal studies. The purpose of this review is to summarize various aspects of adaptive design and evaluate its potential for use in preclinical research.     

Green Adeptness in the Synthesis and Stabilization of Copper Nanoparticles: Catalytic,Antibacterial, Cytotoxicity,and Antioxidant Activities

Copper nanoparticles (CuNPs) are of great interest due to their extraordinary properties such as high surface-to-volume ratio, high yield strength, ductility, hardness, flexibility, and rigidity. CuNPs show catalytic, antibacterial, antioxidant, and antifungal activities along with cytotoxicity and anticancer properties in many different applications. Many physical and chemical methods have been used to synthesize nanoparticles including laser ablation, microwave-assisted process, sol-gel, co-precipitation, pulsed wire discharge, vacuum vapor deposition, high-energy irradiation, lithography, mechanical milling, photochemical reduction, electrochemistry, electrospray synthesis, hydrothermal reaction, microemulsion, and chemical reduction. Phytosynthesis of nanoparticles has been suggested as a valuable alternative to physical and chemical methods due to low cytotoxicity, economic prospects, environment-friendly, enhanced biocompatibility, and high antioxidant and antimicrobial activities. The review explains characterization techniques, their main role, limitations, and sensitivity used in the preparation of CuNPs. An overview of techniques used in the synthesis of CuNPs, synthesis procedure, reaction parameters which affect the properties of synthesized CuNPs, and a screening analysis which is used to identify phytochemicals in different plants is presented from the recent published literature which has been reviewed and summarized. Hypothetical mechanisms of reduction of the copper ion by quercetin, stabilization of copper nanoparticles by santin, antimicrobial activity, and reduction of 4-nitrophenol with diagrammatic illustrations are given. The main purpose of this review was to summarize the data of plants used for the synthesis of CuNPs and open a new pathway for researchers to investigate those plants which have not been used in the past.

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Graphical abstract Proposed Mechanism for Antibacterial activity of copper nanoparticles.

     

Comparative CO2 Adsorption Analysis in Pure and Amine-Modified Composite Membranes

In this study, the CO₂ adsorption analysis in cellulose acetate–TiO₂- and cellulose acetate–3-aminopropyl-trimethoxysilane TiO₂-blended membranes was performed. The membranes were also characterized using scanning electron microscopy and Fourier transform infrared analysis techniques. The adsorption results indicated that 120 and 90°C were considered as optimized temperatures for regeneration of cellulose acetate–TiO₂ and cellulose acetate–3-aminopropyl-trimethoxysilane-modified TiO₂ membranes. The testing results revealed that adsorption capacity reached maximum at 3.0 bars. Validation of experimental results was performed by pseudo-first-order, second-order and intraparticle diffusion models. The correlation factor R² represented that the second-order model was fitted well with the experimental data. The intraparticle diffusion model represented that adsorption is not a single-step process.     

AlBr3 impact on the thermal degradation of P(S-co-MMA): a study performed by contemporary techniques

Pyrolysis of copolymer, [P(S-co-MMA)], in the presence of AlBr₃ was inspected in an inert atmosphere. Five different proportions (copolymer/additive) were chosen. Films were cast from common solvent. It was noticed that copolymer showed more stability on the basis of T _0, however, regions of stability were also observed for the blends. Copolymer showed T ₀ at 260?°C, whereas blends started degrading around 70?°C. T _max was the same for the copolymer and the blends. Low-temperature decompositions of blends were attributed to the generation of free radicals (Br^?) and the zones of stabilizations were assigned to the formation of a ??complex type?? structure between Al and the carbonyl oxygens of MMA units. Degradation products were collected and identified employing Py-GC?CMS technique. Intermediates (solid) at different temperatures (300, 350 and 400?°C) were examined through FTIR spectroscopy. In the light of gathered data, a degradation mechanism was proposed. New products were encountered, viz., bromobenzene, ??brominated?? anhydride ring, etc., which established the chemical interactions between the constituents of the blends, i.e., copolymer and additive. Anhydride rings were absent when poly (methyl methacrylate) was pyrolyzed in the presence of AlBr₃. Oligomers of styrene were not found hinting at the involvement of additive in ??targeting?? the degrading styrene units. The blends indicate 2?C7% residue of original mass; the additive exhibits 9% while the copolymer does not leave residue at the completion of the TG run. The presence of char in the residues of blends suggests that the additive imparts stability to the copolymer. Horizontal burning rate was lowest (6 times less than that of neat copolymer) for [P(S-co-MMA):AlBr₃, 87.5:12.5%], thereby revealing the efficiency of the additive as thermal stabilizer. The highest activation energy was calculated for the copolymer (169.46?kJ/mol) and the range of this parameter for the blends was found from 52.72 to 27.14?kJ/mol.     

Direct printing of copper conductive micro-tracks by multi-nozzle electrohydrodynamic inkjet printing process

To overcome the limitation of low production speed of electrohydrodynamic (EHD) inkjet printing technology and to fabricate low cost electronic micro-structures, this paper presents the direct deposition of copper colloidal solution through the multi-nozzle EHD inkjet printing process. Multi-nozzle EHD inkjet printing head, consisting of five nozzles, was used for simultaneous printing of electrically conductive micro-tracks onto the glass substrate. Nozzle-to-nozzle distance and experimental conditions were optimized to prevent the interaction i.e., cross-talk between electrically charged neighboring jets. After sintering in inert (N₂ gas) atmosphere, printed tracks exhibited approximately five times larger resistivity (9.20 μΩ cm) than that of the bulk copper which is a remarkable achievement. These electrically conductive micro-tracks show the feasibility of multi-nozzle EHD inkjet printing technique using the copper nano-colloidal ink for low cost fabrication of microelectronic structures and devices.     

基于金属氢化物高温蓄热的氢热耦合传递机理

目前大多数可再生能源如太阳能具有间歇性和不稳定性的问题,因此高效蓄热技术成为了发展太阳能的一个关键途径。金属氢化物高温蓄热技术作为热化学蓄热中最有前途的方法之一,受到了人们的广泛关注。为了实现金属氢化物高温蓄热技术的工程应用,明确其氢热耦合传递机理至关重要。本研究采用数值模拟的方法,通过建立反应器的多物理场耦合模型,讨论了不同时刻下床层内部参数的分布,得到了反应锋面的形成和移动机理以及非均匀反应的形成机理;此外,结合反应器内部氢压、接触热阻和床层热阻的变化规律,明确了不同阶段下金属氢化物高温蓄热技术的控制环节;最后,依据金属氢化物高温蓄热技术的工程应用挑战,提出了相应的研究策略。     

Monitoring the Key Components and Elimination of Asphaltenes Precipitation in Crude by a New Alternative Route

The crude composition was determined by distillation on a true boiling point apparatus individually. Then crude naphthas were introduced to a gas chromatograph and asphaltenes were determined by extraction. Quantities of key components were calculated by prescribed mathematical equations. On the basis of relative quantities of key components, 21 blends of 12 crudes were prepared caused asphaltenes precipitation in desalter. Seven blends remained successful, causing no further asphaltenes precipitation, and one of the successful blends was chosen to prepare a batch of 55,000 barrels and was passed through desalter. No further asphaltenes precipitation was found during the whole operation.     

Physiological and Nutraceutical Perspectives of Fructan

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.     

Interfacial activity and micellar morphology of an imidazolium ring containing zwitterionic surfactants

Zwitterionic surfactants based on 3-(1-alkyl-3-imidazolio) propane-sulfonate ([ImS3-R] where R is octyl or dodecyl) is an emerging and important class of amphiphile due to their relevance as nano reactors for the synthesis of metallic nanoparticles and accelerated acid hydrolysis. The physicochemical properties of such synthesized imidazolium ring-containing zwitterionic surfactants have been characterized by surface tension and small-angle neutron scattering (SANS) techniques. Surface tension measurements were used to calculate several thermodynamic parameters over a range of concentrations and temperatures (298–313 K). The results obtained showed a weak signature representing the critical micelle concentration (CMC) for ImS3-8, however, by increasing the alkyl length of the hydrophobic group to dodecyl, that is, ImS3-8 to ImS3-12, the signature of the CMC was much more evident. As expected, the CMC for ImS3-12 shifted to a lower concentration. An increase in temperature increased the surface activity and decreased the CMC of both zwitterionic surfactants, although the changes were small. Compared to classical surfactants, that is, sodium dodecyl sulfate and dodecyl trimethylammonium bromide, the CMC of ImS3-12 is much lower. Modeling of SANS data demonstrated that the morphology of the micelles formed by these amphiphiles may be described by the “classical” model, a central hydrophobic core, with a shell of hydrated headgroups. Due to their widespread applications in colloidal and interfacial science, the present study adds new insight to the fundamental understanding of these interesting imidazolium-based surface-active ionic liquids (ImS3-R).