Search results
(8,361 - 8,380 of 8,523)
Pages
- Title
- Effect of heat treatment on microstructure and electrochemical behavior of laser powder bed fusion hydride- dehydride ti-6al-4v alloy
- Creator
- Delpazir, Melody Honardan
- Date
- 2022
- Description
-
In powder bed additive manufacturing, feedstock and processing have an impact onfinal microstructure and properties of 3D-printed parts. While...
Show moreIn powder bed additive manufacturing, feedstock and processing have an impact onfinal microstructure and properties of 3D-printed parts. While numerous studies have evaluated 3D-printing of spherical powder, very limited research has been carried out on the processing of the non-spherical feedstock. This study is targeted specifically to the use of non-spherical Ti-6Al-4V powders in the laser powder bed fusion (L-PBF) process. Two different post-heat-treatments including hot isostatic pressing and solution treatment are applied. The microstructure evaluation, potentiodynamic polarization, and electrochemical impedance spectroscopy methods are used to characterize L-PBF processed and post- treated specimens. Though as-built part exhibits anisotropic microstructure containing acicular α′ martensite with trace amount of β phase, the heat-treated parts are composed of α+β in which length and thickness of the α-lath depends on the treatment. The below β transus heat treatment leads to the formation of a homogenized grain structures composed of α+β. Electrochemical results show that the below β transus heat-treatment had a slight positive effect on the improvement of corrosion resistivity (corrosion rate of 4.2×10-6 mmy- 1 , which is classified as an excellent ) compared to other conditions, which would be associated to the natural excellent corrosion resistance of Ti-6Al-4V alloy. This slight improvement can be ascribed by the slightly faster formation of a passive layer and its enhanced efficiency because of the presence of the fine-structured β phase in post heat- treated L-PBF processed Ti-6Al-4V alloy.
Show less
- Title
- Keeping the Spark Alive: Examining Associations Between Technology Use For Cybersex, Health and Relationship Satisfaction In Long-Distance Relationships
- Creator
- Khan, Humza
- Date
- 2022
- Description
-
Background: Technology is important to many romantic relationships, especially long-distance relationships (LDR), insofar as technology can...
Show moreBackground: Technology is important to many romantic relationships, especially long-distance relationships (LDR), insofar as technology can minimize the impact of the lack of proximity that is characteristic to LDR. Cybersex, a specific use of technology within romantic relationships, is associated with increased relationship satisfaction among partners in proximal relationships. Cybersex also relates to health broadly, and to anxiety and depression specifically, with mixed associations. Despite LDR lending themselves to cybersex, associations between cybersex, relationship satisfaction, and health have not been studied in LDR. This study has three aims: (1) to provide the first descriptive data related to cybersex behavior, relationship satisfaction and health in LDR; (2) to examine associations between cybersex behaviors and relationship satisfaction, and cybersex and health in LDR; and, (3) to test whether biological sex moderates cybersex-relationship satisfaction and cybersex-health associations among those in LDR. We predicted that cybersex behaviors would relate positively to relationship satisfaction for both males and females, although we predicted males would report stronger associations than females. We predicted cybersex behaviors would relate positively to health for both males and females, although we predicted females would report weaker associations than males. Methods: Participants (N = 146; 18 years or older; English speaking; in LDR for 3+ months) completed a paid online survey on relational experiences and health/well-being. Cybersex behaviors were assessed through an internally created “sex and cybersex behaviors” scale. Relationship satisfaction was assessed via the Couples Satisfaction Index (CSI). Both broad health, and anxiety and depression, were assessed with the PROMIS-29. Correlations were assessed between key study variables. Regression analyses were used first to test associations between cybersex and relationship satisfaction, then cybersex and health, and finally, the moderation effect of biological sex in these associations. Results: The average member of our sample was White, college aged, had no children, a full-time undergraduate student and low SES. Correlation analyses show significant correlations between core study variables (relationship satisfaction, global health, cybersex behavior, depression & anxiety) at some level. Sex-level analyses show that when compared to males, females reported significantly higher average anxiety scores, and more texting sex behavior. Linear regressions established cybersex behavior as a negative predictor of global health and a positive predictor of depression and anxiety, but not relationship satisfaction. Moderation analyses indicated that biological sex moderated the cybersex behavior-global health association such that more cybersex behavior negatively predicted global health for males but not females. Discussion: These differences among sexes and health in LDR observed within our findings may be explained by the social role theory, in which females have worse health than males however, males having worse overall physical health than females may be due to a lack of copresence from their partner. In addition, females engaging in higher levels of texting cybersex may be related to sociocultural factors. Conclusion: Overall, our study contributes to the understanding of cybersex behavior, relationship satisfaction and health outcomes by among males and females in LDR. Our findings suggest that this sample of LDR females engage in more texting cybersex, have higher anxiety symptom severity, and have equal levels of relationship satisfaction.
Show less
- Title
- Efficacy of Organic Acid Treatments for the Reduction of Listeria Monocytogenes on Hard Boiled Eggs
- Creator
- Khouja, Bashayer
- Date
- 2022
- Description
-
Ready-to-eat hard-boiled eggs (HBEs) are a popular and convenient choice for consumers and food servicers. Recentrecalls of hard-boiled eggs...
Show moreReady-to-eat hard-boiled eggs (HBEs) are a popular and convenient choice for consumers and food servicers. Recentrecalls of hard-boiled eggs have highlighted the susceptibility of contamination with Listeria monocytogenes. HBEs are generally treated with antibacterials to ensure the safety and quality of the product. While citric acid is often used, research has determined it is not effective in some situations; therefore, the assessment of additional organic acids is necessary. This study examined the efficacy of acetic, lactic, and malic acid on the reduction of L. monocytogenes on HBEs after a 24- hour treatment trials and 28 days storage trials. Fresh eggs were cooked in boiling water, peeled, and stored at 4°C for 24h before use. For treatment trials, HBEs were dip- inoculated with a 4-strain cocktail of rifampicin resistant L. monocytogenes, resulting in 8 log CFU/egg. Following air drying, hard-boiled eggs were treated at 5 or 25°C with 2% acetic, lactic, or malic acid. L monocytogenes populations were enumerated in intervals up to 24h by homogenization of HBEs with BLEB and cultivation on BHIrif. For pre- treatment storage trials, HBEs were first dip- inoculated with a rifampicin- resistant 4- strain L. monocytogenes cocktail for 20 min, resulting in 1 log CFU/egg, air dried for 10 min, followed by treatment with 2% acetic, lactic, or malic acid for 24 h at either 5 or 25°C. For post- treatment inoculation trials, HBEs were first soaked in 2% acetic, lactic, or malic acid for 24 h at either 5 or 25°C, air dried for 10 min, spot-inoculated at 1 log CFU/egg, and then dried for 20 min. All HBEs were individually stored in bags at 5°C for up to 28 days. The presence of L. monocytogenes was determined at intervals during storage by enrichment with BLEB on BHIrif and Brilliance Listeria Agar. Triplicate eggs were assessed for each timepoint, and three independent trials were conducted. Data were analyzed by Student’s T-test, ANOVA, and Fisher’s exact test, p≤0.05. The initial inoculation level of L. monocytogenes on HBEs was 8.27±0.37 log CFU/egg. After 24 h treatment, all L. monocytogenes populations were significantly reduced on HBEs. At 5°C, populations were reduced by 3.15±0.70, 3.46±0.02, and 4.78±0.23 log CFU/egg. Compared to 5°C, a significantly higher population reduction occurred with acetic and lactic acid when treatment occurred at 25°C. The inactivation of L. monocytogenes on HBEs for the storage trials was associated with the order of the contamination: pre-or post-the acid treatment. Prior storage, L. monocytogenes was detected on 100% of the HBEs. Malic acid pre-treatment was significantly effective in eliminating L. monocytogenes on HBEs at 5 and 25°C, while acetic acid was effective only at 5°C. All acids did not eliminate L. monocytogenes in the case of post-treatment contamination at any tested temperature. The results of this study aid in understanding the efficacy of organic acid treatments against L. monocytogenes on HBEs. Results are useful in the development of preventive controls and guidelines to ensure the safety of HBEs.
Show less
- Title
- ANALYTICAL APPROACH TO ESTIMATE ROTOR TEMPERATURE IN SWITCHED RELUCTANCE MOTOR
- Creator
- Koujalagi, Shweta Manohar
- Date
- 2022
- Description
-
Motors contribute most of the loads. Motors find major applications in automobile industries, household appliances, industrial equipment, and...
Show moreMotors contribute most of the loads. Motors find major applications in automobile industries, household appliances, industrial equipment, and other areas. With the time, engineers and industries found some of the drawbacks or disadvantages of using induction motors in certain applications. They started developing other types of motors that are more efficient than existing ones. Among those, switched reluctance motor, referred as SRM is the one. SRMs are simple in construction, rugged and highly efficient motors.Even though SRM has higher efficiency, it still contribute some losses in the form of heat which will increase the temperature of SRM. If the temperature increases beyond certain limit, cable insulation fails, degrades rotor capability of aligning characteristics, damages bearings, etc. Therefore, it is important to understand the flow of heat in SRM. This thesis focuses on heat transfer analysis from stator coil to rotor of SRM using analytical method and numerical method such as finite element analysis from available coil temperature without using any kind of sensors. Analytical and FEA models are built separately to obtained rotor temperatures at various coil temperatures and rotor speeds. Finally, analytical results are validated with FEA model results. Therefore, once the rotor temperature is estimated accurately, model can be implemented in automotive and other industrial applications to continuously monitor the rotor temperature. It is important to monitor temperature to avoid damage of SRM by thermal effects.
Show less
- Title
- SYNTHESIS AND CHARACTERIZATION OF MG, NB, TI-DOPED LINIO2 CATHODE MATERIAL FOR LI-ION BATTERIES
- Creator
- Tian, Yiwen
- Date
- 2022
- Description
-
In this project, the influence of several metal doping on the electrochemical properties of LiNiO2 materials was analyzed. The doping method...
Show moreIn this project, the influence of several metal doping on the electrochemical properties of LiNiO2 materials was analyzed. The doping method is aiming to improve the stability of the layered structure and inhibit the mixing of nickel and lithium by enhancing the structural stability of the layered material and replacing part of Ni with other metals in the process of intercalation/deintercalation, thereby promoting the cyclic performance and reversible capacity. The LiNiO2 powder doped with Nb, Ti and Mg is denoted as Li0.96Ni0.9Nb0.06Ti0.04Mg0.02O2 or, in short, metal-doped LiNiO2. The synthesis of the metal-doped LiNiO2 powder consists of mixing the lithium and nickel sources with various metal oxides and then being subjected to high-energy ball milling for 10 hours, followed by heating for 20 h in a metallic tube furnace at 680℃ with flowing oxygen atmosphere. The undoped LiNiO2 powder synthesized using the same process and conditions was compared with the doped LiNiO2 powder. In order to understand the doping mechanism, field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD) were used to analyze the morphology, composition and crystal structure of the final product. Benefiting from the Mg, Nb, and Ti doping, the doped LiNiO2 exhibited a high reversible capacity of 130.56 mAh g-1, higher than that of undoped LiNiO2 (95.02 mAh g-1) under the 0.1C charge/discharge rate in the voltage window between 2.5 and 4.2 V. Further, the doped LiNiO2 has 86% of capacity retention over 100 cycles, better than undoped LiNiO2 (only 44% of capacity retention) under the 0.5C charge/discharge rate between 2.5 and 4.2 V.
Show less
- Title
- Child and Family Outcomes Associated with Specific Maryland ASD Waiver Services and Choice and Control as Mediators of These Outcomes
- Creator
- Turchmanovych-Hienkel, Nataliya
- Date
- 2022
- Description
-
Autism spectrum disorder (ASD) is a neurodevelopmental condition that affects 1in 44 children and is characterized by impairments in cognitive...
Show moreAutism spectrum disorder (ASD) is a neurodevelopmental condition that affects 1in 44 children and is characterized by impairments in cognitive, behavioral, and social domains of functioning. Literature suggests that ASD not only impacts the quality of life of the individuals diagnosed with this condition, but also has a negative impact on family quality of life (FQoL). Interventions and services offered through the Medicaid 1915(c) Home and Community-Based Services waiver programs can enhance child and family outcomes. The present study looked at one specific waiver program, the Maryland ASD waiver, and examined the frequency at which families received different waiver services and the associations between those service frequencies and child (i.e., academic performance, independent living skills, social communication and interaction skills, stereotypic and repetitive behavior, and aggressive behavior) and family (i.e., FQoL) outcomes, as well as explored whether the family’s perception of choice and control mediate these child and family outcomes. Results suggest that frequencies of some waiver services are associated with progress in some child outcomes, but not in FQoL. This study also suggests that the choice and control that families have over services do not mediate the relation between frequency of waiver services and child and family outcomes. Overall, results suggest that the Maryland ASD waiver program may help improve some domains of child functioning.
Show less
- Title
- Choice-Distinguishing Colorings of Cartesian Products of Graphs
- Creator
- Tomlins, Christian James
- Date
- 2022
- Description
-
A coloring $f: V(G)\rightarrow \mathbb N$ of a graph $G$ is said to be \emph{distinguishing} if no non-identity automorphism preserves every...
Show moreA coloring $f: V(G)\rightarrow \mathbb N$ of a graph $G$ is said to be \emph{distinguishing} if no non-identity automorphism preserves every vertex color. The distinguishing number, $D(G)$, of a graph $G$ is the smallest positive integer $k$ such that there exists a distinguishing coloring $f: V(G)\rightarrow [k]$ and was introduced by Albertson and Collins in their paper ``Symmetry Breaking in Graphs.'' By restricting what kinds of colorings are considered, many variations of distinguishing numbers have been studied. In this paper, we study proper list-colorings of graphs which are also distinguishing and investigate the choice-distinguishing number $\text{ch}_D(G)$ of a graph $G$. Primarily, we focus on the choice-distinguishing number of Cartesian products of graphs. We determine the exact value of $\text{ch}_D(G)$ for lattice graphs and prism graphs and provide an upper bound on the choice-distinguishing number of the Cartesian products of two relatively prime graphs, assuming a sufficient condition is satisfied. We use this result to bound the choice distinguishing number of toroidal grids and the Cartesian product of a tree with a clique. We conclude with a discussion on how, depending on the graphs $G$ and $H$, we may weaken the sufficient condition needed to bound $\text{ch}_D(G\square H)$.
Show less
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1964
- Creator
- Brandt & Associates
- Date
- 1964
- Description
-
Aerial photograph of the Illinois Institute of Technology campus, looking northeast.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1958
- Creator
- Brandt & Associates
- Date
- 1958
- Description
-
Aerial photograph of the Illinois Institute of Technology campus, looking southwest.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1963
- Creator
- Brandt & Associates
- Date
- 1963
- Description
-
Aerial photograph of the Illinois Institute of Technology campus, looking north.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1950
- Date
- 1950
- Description
-
Aerial photograph of the Illinois Institute of Technology campus, looking southwest. Photographer unknown.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1940
- Date
- 1940
- Description
-
Aerial photograph of the Illinois Institute of Technology campus, looking north. Photographer unknown.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1975
- Creator
- Brandt & Associates, Ltd.
- Date
- 1975
- Description
-
Aerial photograph of Mies Campus, looking north.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1985
- Date
- 1985-10-24
- Description
-
Aerial photograph of Mies Campus, looking north, 1985. Photographer unknown.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- The Cycle, 1938
- Creator
- Armour Institute of Technology
- Date
- 1938
- Description
-
Volume 26 of The Cycle, the 1938 yearbook for the Armour Institute of Technology. The Armour Institute of Technology yearbooks was known by...
Show moreVolume 26 of The Cycle, the 1938 yearbook for the Armour Institute of Technology. The Armour Institute of Technology yearbooks was known by three different titles: Integral (1898-1910), Senior Class Book (1911-1912), and The Cycle (1913-1940). A 1902 volume of Integral is not a part of Galvin Library collections; it is uncertain of a yearbook was published that year. Publication of the Armour Institute ceased in 1941, when the Armour Institute of Technology merged with the Lewis Institute to form Illinois Institute of Technology.
Sponsorship: Scanning of the Armour Institute of Technology yearbooks was supported in part by an award from the Illinois State Historical Records Advisory Board, through funding from the National Historical Publications and Records Commission, National Archives and Records Administration.
Show less - Collection
- Armour Institute of Technology yearbooks, 1898-1940
- Title
- The Cycle, 1934
- Creator
- Armour Institute of Technology
- Date
- 1934
- Description
-
Volume 22 of The Cycle, the 1934 yearbook for the Armour Institute of Technology. The Armour Institute of Technology yearbooks was known by...
Show moreVolume 22 of The Cycle, the 1934 yearbook for the Armour Institute of Technology. The Armour Institute of Technology yearbooks was known by three different titles: Integral (1898-1910), Senior Class Book (1911-1912), and The Cycle (1913-1940). A 1902 volume of Integral is not a part of Galvin Library collections; it is uncertain of a yearbook was published that year. Publication of the Armour Institute ceased in 1941, when the Armour Institute of Technology merged with the Lewis Institute to form Illinois Institute of Technology.
Sponsorship: Scanning of the Armour Institute of Technology yearbooks was supported in part by an award from the Illinois State Historical Records Advisory Board, through funding from the National Historical Publications and Records Commission, National Archives and Records Administration.
Show less - Collection
- Armour Institute of Technology yearbooks, 1898-1940
- Title
- Design Direction, Book 2
- Creator
- Henry, Mary Dill, 1913-2009
- Date
- 1946
- Description
-
Design Direction was Mary Henry's 1946 thesis for her graduate degree at the Institute of Design. The project, completed in collaboration with...
Show moreDesign Direction was Mary Henry's 1946 thesis for her graduate degree at the Institute of Design. The project, completed in collaboration with Emerson Woelffer, was based on a class for beginning students taught by Woelffer at ID. The course consisted of 18 exercises exploring the basic elements of design, each of which is represented in Henry's Design Directions. Book 1 consists of the design exercises themselves, Book 2 contains the textual component of the project.
Show less - Collection
- Mary Dill Henry Papers, 1913-2021
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1964
- Creator
- Brandt & Associates
- Date
- 1964
- Description
-
Aerial photograph of the Illinois Institute of Technology campus, looking north.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1964
- Creator
- Brandt & Associates
- Date
- 1964
- Description
-
Aerial photograph of the Illinois Institute of Technology campus, looking north.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1967
- Creator
- Brandt & Associates
- Date
- 1967
- Description
-
Aerial photograph of the Illinois Institute of Technology campus, looking north.
- Collection
- IIT Campus Aerial photographs, 1940-2002