Purity Conditions Research Articles

Waste to worth: Facile preparation of CaO2 derived from oyster shells for highly efficient degradation of organic contaminants based on Fenton-like system

In recent years, CaO2 has been frequently used as a substitute for H2O2 to address the limitations of H2O2. However, commercially available CaO2 are facing the shortcomings of low purity and limited preparation conditions. Oyster shells can provide superior and abundant biomass calcium element with low cost for developing CaO2. In this work, highly purified CaO2 functional biomaterials were prepared via a facile approach derived from waste oyster shells, which were applied in a Fenton-like system to remove organic pollutants. Experimental results indicated that the oyster shells-derived CaO2 with 100% purity exhibited a greatly enhanced catalytic performance compared with other CaO2 materials in Fenton-like catalytic degradation of organic pollutants, which can be completely removed within 60 s. The high purity of CaO2 would facilitate the release of H2O2 during the Fenton-like catalytic reaction and promote the generation of more active species to oxidize pollutants. Besides, the abundant trace metal elements originated from oyster shells can further motivate the Fenton-like reaction and accelerate the degradation of pollutants, endowing oyster shells-derived CaO2 an excellent catalytic activity. Furthermore, the Fenton-like catalytic mechanism was proposed on basis of tests of radicals trapping and electron spin resonance, validating the vital roles of ⋅OH, ⋅O2– and 1O2 generated throughout the reaction process. This work not only provides a novel and low-cost approach to exploit CaO2 with highly efficient catalytic ability, but also realizes the effective resource utilization of waste shells.

Reflection of Physical Descriptive Parameters as Functional Phenes on Olive Oil Cross-border Mapping

The medicinal and nutritional benefits of olive oil are reflected in its extensive incorporation in many cultures in food and pharmaceutical products. This study suggests the use of colour-based models, viscosity and refractive index as parametric attributes to experiment and track down the authenticity of the oil through image analysis and accurate determination of refractive index and viscosity of oils from different regions.The combination of RGB measurement and chemometric methods (PCA, PCA-class) of olive oil samples collected from distinctive areas (Tunisia, Libya and Egypt) enabled the differentiation of olive oil samples per region of cultivation and was found to be accurate, precise (R2X 0.997) and successful in detecting the accuracy of the labelled information (traceability determination, freshness, purity, date and storage conditions) and could be extrapolated to study the position of harvested areas. The results also revealed a perfect discrimination between the defined categories based on the origin and age after performing the Orthogonal Projection to Latent Structures-Discriminant Analysis (OPLS-DA) on the visible spectra of the samples reaching 90% of correct classifications.

Membrane reactors for hydrogen generation: From single stage to integrated systems

The excessive production of carbon dioxide, the greenhouse effect, and the resulting global warming due to the use of fossil fuels have prompted governments, industry, and researchers toward renewable and clean energy sources. Hydrogen has emerged as a novel carbon neutral energy carrier with the highest specific energy content. Production, storage, distribution, and utilization of hydrogen are rapidly increasing. In this context, the use of hydrogen in power plants, fuel cells and internal combustion engines is constantly being developed. However, widespread use of hydrogen requires its sustainable production at low cost and under high purity conditions, which is the subject of further research. Hydrogen separation using membrane reactors is not a new concept; however, it has gained special attention in the last decades and represents a relevant and promising option to potentially overcome the above mentioned problems. This review examines advances in industry and research in hydrogen utilization, hydrogen production using membrane reactors, the nature and physicochemical properties of membranes, and the various configurations of membrane reactors. The effects of membrane reactors on the interplay of temperature, pressure, reactant conversion, hydrogen production, and thermodynamic equilibrium are explained, and the results are compared with those of conventional reactors. Finally, fuel cells, solar collectors, and their integrability into membrane reactors are discussed.

Effects of annealing on particle size and pore size distribution of hydrothermally synthesized BaTiO3 nanopowders and their grain-growth kinetics during sintering

With an increase in the annealing temperature, the hydrothermally synthesized BaTiO3 nanopowders increased in particle sizes from 100 to 260 nm and decreased in pore volume from 7.2 to 2.82 cm3 g−1, while the pore size remained constant at 3.06 nm. Samples with different initial particle sizes were sintered in the temperature range of 1210 °C–1300 °C and for periods of 0.5–48 h at 1270 °C. The kinetic grain-growth exponent of the sintered BaTiO3 samples, n, was proportional to the increase of an initial particle size and the decrease of pore volume, and the grain growth obeyed the Arrhenius equation. The activation energies for the grain growth of the sintered BaTiO3 samples with initial particle size of 100, 155 and 260 nm were 737, 702 and 755 kJ mol−1, respectively, indicating that the activation energy was independent of the initial particle size in the range of 100–300 nm under identical purity conditions, and pore volume was supposed to be attributed to the velocity of grain growth.

Generation of cross-spectrally pure electromagnetic fields using a pair of moving diffusers.

In this paper, we demonstrate that the vector light field is cross-spectrally pure if it passes through two diffusers (having similar correlation properties) moving with identical linear speeds in opposite directions. To determine the spatio-temporal coherence function of cross-spectrally pure light, a double slit is placed just after the second diffuser. We show that the normalized space-time coherence Stokes parameters of emerging light can be described in the form of a reduction formula, whereas the absolute values of the normalized space-frequency coherence Stokes parameters are the same for every frequency component of the light field. These are the conditions of cross-spectral purity of Stokes parameters. We further prove that at zero time delay, the condition of strict cross-spectral purity is validated. Furthermore, we establish the conditions for cross-spectral purity for a vector light field passing through the aforesaid diffusers, when they rotate with identical angular speeds in opposite directions, offering a possibility to optimize the scheme using only a single diffuser. For the first time, to our knowledge, an additional condition for equality of the degree of cross-polarization in space-time and space-frequency domains for strict cross-spectrally pure light beams is also introduced.

(Invited, Digital Presentation) The Challenge of Automated High-Throughput Experiments on a Variety of Powder Libraries

In recent years, "Materials Genome Initiative (MGI)", "Materials Informatics (MI)", and "Process Informatics (PI)" research have attracted much attention as keywords for high-throughput materials discovery. Much of the MI and PI research that has been published so far emphasizes data mining, statistics, machine learning, and predictive analytics. The MGI proposed by the US government in 2011 indicated that material innovation requires "experimental tools" in addition to "computational tools" and "digital data. "Experimental tools" means the creation of big data using automated high-throughput synthesis, evaluation and analysis systems, but there are not many examples of this development. In order to promote highly accurate materials discovery, a three-way relationship is important. And in order to improve the overall speed of exploration, all processes need to be accelerated. In the production of ceramic powder, which is also the synthesis process of dielectrics, the crystalline phase and grain size vary depending on the raw material manufacturer, purity, sintering atmosphere, sintering temperature, and other conditions. These have a great impact on the physical properties. It is important to create a data set that includes not only composition, phase identification results, lattice parameters, and physical property data, but also detailed experimental process conditions. If the data can be collected in a unified high-throughput experimental environment, it will greatly contribute to data interpolation in MI and PI research. We expect that combining the data obtained from high-throughput automated experiments with the data-driven research found in MI and PI will accelerate more accurate research. To achieve this goal, we are continuing to work on the development of combinatorial technology, a high-throughput synthesis, evaluation, and analysis technique for multi-component ceramic powders. For the preparation of powder samples consisting of a vast number of combinations, we have developed two methods based on wet processes.1)2) These devices allow us to synthesize 100 samples per day, reducing the amount of raw material used per sample to about 1/1000. This has the advantage of not only increasing the high-throughput but also reducing the excessive use of raw materials. After the library is created, the crystal structure needs to be evaluated. In recent years, the high-speed detectors of experimental X-ray diffractometers have made it possible to obtain X-ray diffraction patterns in a short time. In 2014, Gregoire et al. developed a technique to simultaneously collect synchrotron XRD and XRF data for a group of multi-component thin film samples. They developed a technique to collect the data and showed that they could collect at least 5000 patterns per day in less than 18 seconds per sample3). Furthermore, Kusune et al. matched the synchrotron thin-film XRD patterns with the Inorganic Crystal Structure Database (ICSD) using an on-the-fly method, and greatly improved the classification accuracy of structural phases overlapping in the three-component reaction diagram.4) The use of XRD patterns for informatics is often discussed between phase information, lattice constants and physical properties, but crystallographic information such as fractional coordinates should be added to the data set if genomic machine learning is to be promoted. In order to obtain the diffraction intensities for high-throughput synthesized samples, which are necessary for structural refinement, collaboration with synchrotron radiation is required. We propose a high-throughput crystallographic information collection process combined with efficient measurement tools and an automated structure refinement program.5,6) 1) K. Fujimoto et al., Measurement Science and Technology 16 41-45 (2005).2) K. Fujimoto et al., Solid State Ionics 177 2639-2642 (2006).3) J. M. Gregoire et al., Journal of Synchrotron Radiation, 21(6), 1262-1268 (2014).4) Aaron Gilad Kusne et al., Scientific Report, 4: 6367 (2014).5) A. Aimi et al., ACS Combinatorial Science 22(1) 35-41 (2020).6) K. Fujimoto et al., ACS Combinatorial Science 22(12) 734-737 (2020).

Understanding Mother Worship and the Feminist Resistance to the Ethos of Motherhood

Motherhood is a complex topic to take up for research. A simple yet a very complicated phenomenon in any society. In India motherhood assumes altogether a different tone in the sense that even though India worships every forms of being a woman (and especially the way every aspect of motherhood is celebrated and worshipped), it goes quite contrary to the maternal health statistics, sex ratio statistics and gender induced violence statistics. And how this inequality has emerged in a strong corporate sector which is a night mare of women. In the present times motherhood and bareness are two complicated realities; it comes with a lot of conditions of purity and gender choice and cultural baggage of bareness and inauspiciousness. Despite all the debate surrounding inequalities, violence and gender induced discrimination against women; it cannot be blatantly denied that women have not made a mark for themselves.

Variation of air condition parameters, in the conditions of the presence of carbon monoxide, in the duct of ventilation installations

Industrial ventilation and air conditioning systems aim to ensure the conditions of air purity and microclimate corresponding to the activity of man and the nature of the technological process. The parameters of the state of the air which are of interest for the technique of ventilation and air conditioning are: air temperature and humidity, atmospheric pressure, and air speed. For the study on the variation of the air state parameters inside the industrial ventilation installations, in the experiment laboratory, on the study of the industrial ventilation systems, the experiment was performed on the variation of the air state parameters in the conditions of circulation through the ventilation duct a quantity of carbon monoxide at constant pressure. Prior to the introduction of carbon monoxide into the piping, the ventilation system was started at nominal parameters. During the experiment, the operating parameters of the drive motor were changed using a frequency converter on levels 50; 40; 30; 20; 10 and 5 Hz. The ventilation system used was structured by means of flow converters which were fixed in the open position. The ventilation system as well as the flow variators were operated by the SCADA type command and control system. The paper will present the analysis of the variation of state parameters (temperature, humidity, absolute pressure, and air speed) by introducing a constant amount of carbon monoxide in the ventilation duct.

The General F_(a,λ) (K,T)- Structure Satisfying aF^K+λ^r F^T=0 on M^n and Lifts Problems Associated with the Structure

In this paper our aim is to get the general structure equation which covers previously acquired structures. In this context this paper consists of three main sections. In the first section, we define the general F_(a,λ) (K,T)-structure satisfying aF^K+λ^r F^T=0,(F≠0,K≥3,T≥1 and (K≥T),a and λ are non zero complex numbers, r some finite integer) on manifold M^n and studied to give some special examples. The second part, we find the integrability conditions by calculating Nijenhuis tensors of the horizontal lifts of the general F_(a,λ) (K,T)-structure satisfying aF^K+λ^r F^T=0. Later, we get the results of Tachibana operators applied to vector and covector fields according to the horizontal lifts of the general F_(a,λ) (K,T)-structure in cotangent bundle T^* (M^n). In addition, we have studied to show the purity conditions of Sasakian metric with respect to the horizontal lifts of the structure. In the final section, all results obtained in the second section were investigated according to the complete and horizontal lifts of the general F_(a,λ) (K,T)-structure on tangent bundle T(M^n).

Effects of carbon dioxide purities on mitotic index in lymphocyte culture and metaphase chromosome quality

Abstract. Purnami S, Wibisari IP, Suvifan VA, Nurhayati S, Ramadhani D. 2021. Effects of carbon dioxide purities on mitotic index in lymphocyte culture and metaphase chromosome quality. Nusantara Bioscience 13: 171-176. The metaphase chromosome spread quality is necessary for a faster individual dose prediction following radiological accidents using dicentric chromosome assay. It is well known that the low-quality metaphase chromosome spreads can lead to false positives of dicentric chromosome identification. Thus, evaluation of the main variable that influences the preparation of high-quality metaphase chromosome spreads is important to perform. Until now, no studies have assessed the effects of CO2 purities on metaphase chromosome spread quality. This study aimed to evaluate the effects of carbon dioxide (CO2) purities on lymphocyte proliferation, and the quality of metaphase chromosome spreads to improve the chromosome aberration assay for cytogenetic biodosimetry purposes. Whole blood samples from three different subjects were cultured and incubated for 48 hours with two different grades of CO2 (high purity and food grades) and without CO2. The mitotic index (MI) from each subject was assessed, and the quality of metaphase chromosome spreads was evaluated by comparing the lengths of chromosomes 1, 2, and 21. Statistical analysis revealed that the difference between manual and automatic MI under three different conditions of CO2 purity was not statistically significant (p = 0.162; p = 0.901). Comparative analysis of the lengths of chromosomes 1, 2, and 21 from 145 metaphases also showed a difference that was not statistically significant (p = 0.745; p = 0.915; p = 0.399). Overall, our findings suggest that CO2 purities do not impair lymphocyte proliferation or metaphase quality. Further investigation should include other technical improvements such as drop-slide optimization.

Additive manufacturing and direct synthesis of sphene ceramic scaffolds from a silicone resin and reactive fillers

Sphene (CaTiSiO5, i.e. CaO·TiO2·SiO2) ceramics were successfully developed via the polymer derived ceramics route, starting from a commercial silicone containing specific oxide fillers. The approach allowed the combination of synthesis, in conditions of high phase purity, and advanced manufacturing. In particular, the adopted starting materials enabled an easy preparation of pastes, to be used for direct ink writing (DIW) of three-dimensional reticulated scaffolds. Sphene scaffolds, after firing at 1300 °C, were always regular and crack-free, despite changes in the line spacing, resulting in variable porosity (from ≈ 59 to 74 %), and exhibited a compressive strength from 3.9 to 12.7 MPa. The porosity was actually hierarchical, considering the formation of ‘spongy’ struts. In vitro tests, with increasing immersion time in SBF solution, confirmed the bioactivity, combined with a quite slow ion release, useful to maintain the pH value at nearly physiological values. Additional biological tests, consisting of the seeding of scaffold with normal human adult dermal fibroblasts, showed adequate cell viability and no toxicity effect.

SOME RESEARCH NOTES ON LIFTS OF THE HSU – (4,2) STRUCTURE ON COTANGENT AND TANGENT BUNDLE

There are a lot of structures in tangent and cotangent bundle. One of them is the Hsu – (4,2) structure have been defined and studied by Yano, Hough and Chen [1] and the complete and horizontal lifts of Hsu – (4,2) structure extended in M^n to cotangent bundle by R. Nivas and M. Saxena [2]. Hsu-structure had been defined firstly by Prof Mishra [3]. This paper consists of two main sections. In the first part, we find the integrability conditions by calculating Nijenhuis tensors of the complete and horizontal lifts of Hsu – (4,2) structure. Later, we get the results of Tachibana operators applied to vector and covector fields according to the complete and horizontal lifts of Hsu – (4,2) structure and the conditions of almost holomorfic vector fields in cotangent bundle T^* (M^n ). Finally, we have studied the purity conditions of Sasakian metric with respect to the lifts of Hsu – (4,2) structure. In the second part, all results obtained in the first section were investigated according to the complete and horizontal lifts of the Hsu – (4,2) structure in tangent bundle T^* (M^n ).

Some notes on lifts of the F((υ+1),λ²(υ-1))-structure on cotangent and tangent bundle

The F^{v+1}-λ²F^{v-1}=0 structure (v≥3) have been studied by Kim J. B. K75 . Later, Srivastava S.K studied on the complete lifts of (1,1) tensor field F satisfying structure F^{v+1}-λ²F^{v-1}=0 and extended in Mⁿ to cotangent bundle. This paper consists of two main sections. In the first part, we find the integrability conditions by calculating Nijenhuis tensors of the complete and horizontal lifts of F^{v+1}-λ²F^{v-1}=0. Later, we get the results of Tachibana operators applied to vector and covector fields according to the complete and horizontal lifts of F((v+1),λ²(v-1)) -structure and the conditions of almost holomorfic vector fields in cotangent bundle T^{∗}(Mⁿ). Finally, we have studied the purity conditions of Sasakian metric with respect to the lifts of F^{v+1}-λ²F^{v-1}=0-structure. In the second part, all results obtained in the first section were investigated according to the complete and horizontal lifts of the F^{v+1}-λ²F^{v-1}=0 structure in tangent bundle T(Mⁿ).

Impurity driven corrosion behavior of HAYNES® 230® alloy in molten chloride Salt

The impurity-driven corrosion behavior of HAYNES® 230® alloy in the molten KCl-MgCl2-NaCl salt was studied at 800 °C for 100 h with different salt purity conditions. It was found that HAYNES® 230® alloy exhibited better corrosion resistance in the salt with lower impurities. Furthermore, the corrosion (non-immersion) due to molten salt vapors was more severe at higher temperature. The attack was localized and driven by outward diffusion of chromium through the grain boundaries. The presence of Mg in its metal form in the salt resulted in an even higher mass-loss in HAYNES® 230® alloy due to Mg-Ni interaction.

Cross-spectral purity of nonstationary vector fields in space–time and space–frequency domains

We establish the concept of cross-spectral purity for nonstationary electromagnetic fields having any degree of coherence or polarization. The conditions of cross-spectral purity in all Stokes parameters are derived for both space-time and space-frequency domains, which demonstrate that the normalized two-point coherence properties of such fields can be expressed as products of a spatial and a time (or frequency) dependent function. We further determine the condition of strict cross-spectral purity for nonstationary fields, which establishes the equivalence of normalized two-point Stokes parameters governing the spatial factors of the space-frequency and space-time domains. This study may provide interesting aspects of statistical properties of beams obtained from practically available sources such as pulsed lasers, modulated and fluctuating light sources, etc.

Ultrahigh purity conditions for nitride growth with low oxygen content by plasma-enhanced atomic layer deposition

Ultrahigh purity (UHP) reactor conditions provide a process environment for growth of nitride thin films with low oxygen content by plasma-enhanced atomic layer deposition (PEALD). In particular, UHP conditions correspond to partial pressures below 10−8 Torr for impurities within the PEALD process environment to limit incorporation before, during, and after film growth. In this article, we identify the various sources of background oxygen species and describe the measures taken to obtain UHP reactor conditions. For example, in situ ellipsometry results are presented that reveal the impact of oxygen incorporation on film resistivity during and after titanium nitride PEALD due to elevated levels of oxygen impurities in the argon process gas. A model is also developed that shows the significance of water permeation through elastomer vacuum seals. These examples demonstrate the importance of process gas purification and elimination of elastomer permeation toward achieving a UHP environment. X-ray photoelectron spectroscopy (XPS) depth profile data for titanium, aluminum, and silicon nitride by PEALD reveal bulk oxygen levels below 1 at. %, thereby demonstrating the effectiveness of UHP reactor conditions at reducing oxygen incorporation. Consistent with XPS, depth profile secondary ion mass spectroscopy results for titanium nitride PEALD confirm bulk oxygen content less than 1 at. %, further establishing the effectiveness of a UHP background for high purity nitride film growth.

On the Integrability Conditions and Operators of the F((K + 1),(K − 1))− Structure Satisfying F K+1 + F K−1 = 0, (F 6= 0, K 1 2) on Cotangent Bundle and Tangent Bundle

This paper consists of two main sections. In the first part, we find the integrability conditions of the horizontal lifts of $F((K+1),(K-1))-$ structure satisfying $F^{K+1}+F^{K-1}=0,$ $(F\neq 0,$ $K\eqslantgtr 2)$. Later, we get the results of Tachibana operators applied to vector and covector fields according to the horizontal lifts of $F((K+1),(K-1))-$structure in cotangent bundle $T^{\ast }(M^{n})$. Finally, we have studied the purity conditions of Sasakian metric with respect to the horizontal lifts of the structure. In the second part, all results obtained in the first section were obtained according to the complete and horizontal lifts of the structure in tangent bundle $T(M^{n})$.

Purity in compactly generated derivators and t-structures with Grothendieck hearts

We study t-structures with Grothendieck hearts on compactly generated triangulated categories $${\mathcal {T}}$$ that are underlying categories of strong and stable derivators. This setting includes all algebraic compactly generated triangulated categories. We give an intrinsic characterisation of pure triangles and the definable subcategories of $${\mathcal {T}}$$ in terms of directed homotopy colimits. For a left nondegenerate t-structure $$\mathbf{t}=({\mathcal {U}},{\mathcal {V}})$$ on $${\mathcal {T}}$$ , we show that $${\mathcal {V}}$$ is definable if and only if $$\mathbf{t}$$ is smashing and has a Grothendieck heart. Moreover, these conditions are equivalent to $$\mathbf{t}$$ being homotopically smashing and to $$\mathbf{t}$$ being cogenerated by a pure-injective partial cosilting object. Finally, we show that finiteness conditions on the heart of $$\mathbf{t}$$ are determined by purity conditions on the associated partial cosilting object.

Overpressure Chamber for Testing in High Air Purity Conditions

Volatile organic compounds (VOC) released into the air contribute to adverse climate changes, discomfort, and harmful effects on the human body. Principal sources of VOC emissions are industrial processes and, in the case of rooms for human residence, building materials and indoor furnishings. VOC emissions are monitored and restricted in line with legislation prevailing in the European Union and most countries of the world. The chamber method is used to measure noxious substance emissions from building materials and indoor furnishings. The paper analyses the impact of regulatory requirements concerning emission test parameters and apparatus on technical solutions as part of air preparation assemblies and emission measurement chambers. The design of a 0.225m3 steel chamber is presented, which was developed by our Institute based on our experience in the design and construction of similar apparatus. Results of verification testing are described.

SUCROSE CRYSTALLIZATION: MODELING AND EVALUATION OF PRODUCTION RESPONSES TO TYPICAL PROCESS FLUCTUATIONS

Abstract This work describes a phenomenological model of the two-massecuite system for sucrose crystallization, developed using EMSO software. In most Brazilian sugarcane industries, sucrose crystallization is performed using this system. This process is considered to be a fundamental step in obtaining sugar of the desired quality and accounts for a substantial fraction of the production costs. The simulation results - crystal percentage in massecuite, brix and purity of molasses, magma purity, sugar pol, crystal size distribution - were validated by comparing them with real process data of an industrial plant. The interest of the phenomenological model to study the possible impacts of impurities and process instability was illustrated by varying the simulation inputs related with the syrup purity, syrup brix and steam conditions.