Demonstration and Assessment of Purification Cascades for the Separation and Valorization of Hemicellulose from Organosolv Beechwood Hydrolyzates

Hemicellulose and its derivatives have a high potential to replace fossil-based materials in various high-value-added products. Within this study, two purification cascades for the separation and valorization of hemicellulose and its derived monomeric sugars from organosolv beechwood hydrolyzates (BWHs) were experimentally demonstrated and assessed. Purification cascade 1 included hydrothermal treatment for converting remaining hemicellulose oligomers to xylose and the purification of the xylose by nanofiltration. Purification cascade 2 included the removal of lignin by adsorption, followed by ultrafiltration for the separation and concentration of hemicellulose. Based on the findings of the experimental work, both cascades were simulated on an industrial scale using Aspen Plus®. In purification cascade 1, 63% of the oligomeric hemicellulose was hydrothermally converted to xylose and purified by nanofiltration to 7.8 t/h of a xylose solution with a concentration of 200 g/L. In purification cascade 2, 80% of the lignin was removed by adsorption, and 7.6 t/h of a purified hemicellulose solution with a concentration of 200 g/L was obtained using ultrafiltration. The energy efficiency of the cascades was 59% and 26%, respectively. Furthermore, the estimation of specific production costs showed that xylose can be recovered from BWH at the cost of 73.7 EUR/t and hemicellulose at 135.1 EUR/t.

Embodying Meaning Visually: From Perceptual Dynamics to Motion Kinematics

This paper adopts an embodied cognitive perspective to review the significance of dynamic patterns in the visual expression of meaning. Drawing upon the work of Rudolf Arnheim we first show how perceptual dynamics of inanimate objects might be extended in order to structure abstract meaning in fixed images such as paintings. Second, we evaluate existing experimental work that shows how simple kinematic structures within a stationary frame might embody such high-level properties as perceptual causality and animacy. Third and last, we take inspiration from these experiments to shed light on the expressiveness of dynamic patterns that unfold once the frame itself becomes a mobile entity (i.e., camera movement). In the latter case we will also present a filmic case study, showing how filmmakers might resort to these dynamic patterns so as to embody a film’s story content, while simultaneously offering a further avenue for film scholars to deepen their engagement with the experimental method.

Extraction of Essential Oil Form Sweet Lime Orange Peel: A Comparison Study

This research work was designed to extract essential oil from sweet lime peel (solid waste). The feed material selected for study is sweet lime peel. The disposal of waste product such as peels often has a legal restriction problem and treatment process involved requires higher costs. Transformation of this waste in to useful products could cut global treatment costs. Hence the objective of our experimental work was to convert sweet lime peel in to essential oil which is in huge demand in food, pharma and cosmetic industry. In our experimental work eextraction of essential oil was evaluated and comparison study was made between steam distillation, hydro-distillation, solvent extraction and hydro-steam distillation. Maximum extraction yield of 2.4 % was achieved at 90 min of contact by hydro-distillation. Hydro-distillation method offers advantages in comparison with other three methods in terms of energy saving, cleanliness and reduced waste water. Chemical constituents of essential oil samples were evaluated in terms of qualitative and quantitative analyses by gas chromatography/mass spectrometry and physical techniques. The chemical profile includes thirty two components which were identified in the extracts by Gas chromatography-Mass spectroscopy (GC-MS) analysis. The dominant component identified was limonene (65 .2 to 72.8%).

PERFORMANCE OF DIFFERENT PHOTOVOLTAIC TECHNOLOGIES FOR AMORPHOUS SILICON (A-SI) AND COPPER INDIUM GALLIUM DI-SELENIDE (CIGS) PHOTOVOLTAIC MODULES

In this work, the analysis of performance of two types of photovoltaic (PV) (Amorphous Silicon (a-Si) Copper Indium Gallium Diselenide (CIGS) technologies were achieved out under under Iraqi (Baghdad)climate conditions. The elevation of the selected site is 9 m above ground level. The experimental work covered the eight commercially available PV technologies. The two technologies that employed in this work are, Amorphous Silicon (a-Si) and Copper Indium Gallium Diselenide (CIGS). The total period of the experimental work was 7 months, and the data were analyzed simultaneously. Special attention is given to the influence of temperature and solar radiation the performance of the PV modules. Where, it was proposed a simple I-V curve test for PV modules. The results showed that the proposed system successfully experimentally extracted I-V curves of the selected two PV modules (amorphous and CIGS solar modules). The maximum values of power (Pmax) at solar radiation intensity 750 W/m² are 2.742 W, and 2.831 W for amorphous silicon and copper indium gallium di-selenide respectively. This is occurred because the lowest solar module operating temperature (19 oC and 17 oC for solar radiation 750 and 1000 W/m2 respectively) and ambient temperature (7 oC) and for Jan., 2021 than other months. Consequently, the same behavior for the two modules at solar irradiance 1000 W/m2 with the highest power value; 2.680 W, and 3.198 W of amorphous silicon and copper indium gallium di-selenide respectively. Furthermore, the minimum values of power (Pmax) at solarradiation intensity 750 W/m² are 2.530, and 2.831 for amorphous silicon and copper indium gallium di-selenide respectively because we have the highest solar module operating temperature (57 oC, and 55 oC respectively) and ambient temperature (45 oC) for April, 2021 than other months. Consequently, the same behavior for the two modules at solar irradiance 1000 W/m2 with the highest power value; 2.680 W, and 3.198 W of amorphous silicon and copper indium gallium di-selenide respectively. The highest efficiency can be notes for CIGS solar module with a value 7.3%, while the lowest one is 5.5% for amorphous solar module.

Flow Disturbing to Enhance Heat Transfer Inside a Duct: an Experimental Study

In the present experimental work, the effect of air circulation on increasing heat transfer rates within the duct was studied. Three air circulation speeds are implemented: 2400, 1800, and 1200 rpm. In addition, the effect of the distance between the heat source and the location of the circulating fan on heat transfer rates was investigated using three different distances: 20, 40, and 60 cm. The Exhaust fan, placed at the outlet of the duct, changed its speed to three values: 2850, 2140, and 1425 revolutions per minute. The Reynolds range ranged from 65,000 to 175,000. The results showed that the best thermal performance is achieved when the exhaust fan speed, air circulation speed, and the distance between the heat source are 1425 rpm, 2400 rpm, and 60 cm, respectively.

Selection and organization of speech material for teaching students of Linguistics foreign-language speaking. Part I

The problem for the research. Modern social contract requires linguistic departments and universities to create the most favourable conditions for teaching students oral productive foreign-language speech in order to develop their universal, general professional and professional competencies. The problem of the research is connected with the solution of the issues of selection and organization of speech material, adequate to the tasks of teaching speaking at the Linguistics Department to ensure interpersonal, intercultural and professional interaction of students. Methods of investigation. Experimental teaching students foreign-language speaking on the basis of the principles of selection and organization of speech material, proposed in the article, was carried out at the Linguistics Department of Vyatka State University (32 first-year students, speciality 44.03.05 Pedagogical Education (with two profiles), the training focus “English, German”). Quantitative and qualitative criteria for evaluating students’ monologic and dialogical speech were developed. The criteria were reflected in the subsystem of informative and analytical training exercises, as well as speech ones on the controlled use of materials of educational conversational texts, on working with model dialogues, for teaching prepared and spontaneous oral speech. The findings of the study. The results of the experimental work indicate that the proficiency in foreign-language monologic speech (cycle 1) increased in 56% of students; dialogical speech (cycle 2) – in 66 %. The calculation of G-criterion of signs revealed that at the end of the 1st cycle Gemp. ≤ Gcr. (0 ≤ 5); at the end of the 2nd one Gemp. ≤ Gcr. (0 ≤ 6). This indicates that the shift in the typical direction in our case is not accidental, and with 95 % of confidence it can be stated that it is due to the conduct of experimental work. Conclusions. The purpose of the article is achieved. It presents the typology of speech material for teaching foreign-language speaking at the Linguistics Department; the principles and products of its selection and organization. It is proved that taking into account the proposed principles improves the quality of teaching an oral productive type of foreign-language speech activity and contributes to the development of universal, general professional and professional competencies of students.

Experimental Work for Bar Straightness Effect Evaluation of Split Hopkinson Pressure Bar

Bar straightness is one of several factors that can affect the quality of the strain wave signal in a Split Hopkinson Pressure Bar (SHPB). Recently, it was found that the bar components of the SHPB at the Lightweight Structures Laboratory displayed a deviation in straightness because of manufacturing limitations. An evaluation was needed to determine whether the strain wave signals produced from this SHPB are acceptable or not. A numerical model was developed to investigate this effect. In this paper, experimental work was performed to evaluate the quality of the signal in the SHPB and to validate the numerical model. Good agreement between the experimental results and the numerical results was obtained for the strain rates and stress-strain relationship for mild steel ST37 and aluminum 6061 specimen materials. The recommended bar straightness tolerance is proposed as 0.36 mm per 100 mm.

Comparative and correlation analysis of experimental work on the formation of readiness to conduct intra-university quality monitoring

The problem of the formation of the teacher's readiness to conduct intra-university monitoring of the quality of students' education is considered. On the basis of the developed system for the formation of a teacher's readiness to conduct intra-university monitoring of the quality of student learning, it is currently a mechanism for managing this process. The article presents the materials of the correlation analysis of the results of experimental work on the formation of a teacher's readiness to conduct intra-university monitoring of the quality of student learning, considered as an integrative personality trait, a system-forming information-research, operational-activity, analytical, reflective and managerial components reflecting the level of knowledge and skills to apply methods, technologies and means of conducting intra-university monitoring of the quality of student learning, to assess the quality of mastering an academic discipline. Based on the materials of experimental work, the relationship between the components of readiness and between the dominant indicators in their structure is proved. In the course of a comparative analysis of the results of the ascertaining and formative experiments, a connection was established between the types of teacher's readiness to conduct intra-university monitoring of the quality of student learning, which proves its integrative nature, and their compensatory role was also revealed due to the dominant indicators. In the course of the implementation of the developed system, the teachers' need for solving innovative problems increased (an indicator of the managerial type of readiness). The results obtained indicate the development of all components of readiness in the process of professional development. The analysis carried out allows us to speak about the possibility of forming the types of teacher readiness to conduct intra-university monitoring of the quality of student learning due to the compensatory properties of the types of readiness.

Identifying Wheel-Thrown Vases in Middle Minoan Crete? Preliminary Analysis of Experimental Replicas of Plain Handleless Conical Cups from Protopalatial Phaistos

Recent work in Middle Bronze Age Crete has revealed that most Protopalatial or First Palace period pottery is produced through the use of a combination of coil-building and the wheel, i.e., wheelcoiling. Experimental work conducted on pottery from Minoan sites of Northern and Eastern Crete (e.g., Knossos, Myrtos Pyrgos, Palaikastro) has indeed determined that Minoan potters did not develop the skills required to adopt the wheel-throwing technique. However, my recent technological study of Protopalatial ceramic material from Middle Minoan IIA (19th century BC) deposits from the First Palace at Phaistos, in Southern Crete, has revealed that though pottery was produced by the wheelcoiling techniques, yet other forming techniques were practised too. In this paper I present a preliminary analysis of experimental replicas of MM IIA Phaistian plain handleless conical cups, manufactured on the potter’s wheel using three different forming techniques: wheel-pinching, wheel-coiling, and throwing-off-the-hump. This analysis will proffer answers to several questions on the use of the potter’s wheel in Middle Bronze Age Crete and opens the possibility that at MM IIA Phaistos there co-existed potters who had developed skills to employ different forming techniques on the wheel, including possibly that of throwing-off-the-hump.