Preferred Language
Articles
/
jbcd-445
The effect of in office bleaching on surface roughness and micro-hardness of newly developed composite materials (In vitro study)
...Show More Authors

Background: Alterations in the microhardness and roughness are commonly used to analyze the possible negative effects of bleaching products on restorative materials. This in vitro study evaluated the effect of in-office bleaching (SDI pola office +) on the surface roughness and micro-hardness of four newly developed composite materials (Z350XT –nano-filled, Z250XT-nano-hybrid, Z250-mico-hybrid and Silorane-silorane based). Materials and methods: Eighty circular samples with A3 shading were prepared by using Teflon mold 2mm thickness and 10mm in diameter. 20 samples for each material, 10 samples for base line measurement (surface roughness by using portable profillometer, and micro-hardness by usingDigital Micro Vickers Hardness Tester), and 10 samples for after bleaching measurement. The appropriate bleaching procedure was performed on the top surface of test groups for 90 minutes total bleaching period. Then surface roughness and hardness were tested at the end of the duration. Statistical analysis was carried out using ANOVA, LSD and t-test. Results: There was a highly significant increase in surface roughness of all tested groups after bleaching. There is a highly significant increase in micro-hardness for Z250, there is decrease in Micro-hardness for siloraneand Z250xt and there is a non-significant increase in micro-hardness of Z350xt. Conclusion: bleaching has a negative effect on surface roughness of all the tested materials, as surface roughness increased after bleaching. Micro-hardness is a material dependent, there is different reaction to bleaching depending on the resin, load and size of the fillers used in the materials. Nano-filled composite is the material that has better performance than the other tested materials, as it is the material that has the least affection by bleaching.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Feb 06 2026
Journal Name
International Journal Of Law And Society
Mechanisms for Achieving a Green Economy and Practical Challenges
...Show More Authors

In light of accelerating environmental degradation, the transition to a green economy is an imperative for achieving sustainable development. This study provides a critical analysis of the international legal and institutional framework governing this transition, revealing a significant gap between normative developments and the institutional framework on one hand, and their practical implementation on the other. The transition faces legal obstacles, including reliance on non-binding voluntary commitments and conflicts between environmental obligations and global trade and investment rules. It also reveals a significant financing gap, as financial flows to developing countries continue to lag behind commitments, in add

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Oct 05 2016
Journal Name
Al-academy
Dialectical relationship between digital Technique and aesthetic Picture TV
...Show More Authors

The technical development has significant effects on the mediator Alcinmatugrave, and TV originated mainly based on technical, with the development and the continuation of these technologies and the enormous impact on the level of the television picture, initially dramas in recent times approaching in the aesthetic composition of the film thanks to the employment of modern digital technologies, Montag was not only one of the cinematic elements that went into television thanks to technical developments analogue and digital, and which added the possibility of large processors in the picture, high-definition digital cameras that have led to dispense often for artificial lighting intensive imaging light available, as these cameras have helpe

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Sep 15 2022
Journal Name
Al-academy
Production mechanisms and their implications for Iraqi theater techniques
...Show More Authors

Theatrical production mechanisms were determined according to the extents of the theatrical performance, the directing plan, and the ideas that the theatrical performance seeks to convey to the audience. Accordingly, theatrical production mechanisms differ between one theatrical performance and another according to the requirements of each of them and the surrounding circumstances that accompany the production of theatrical performance, and in order to search for production mechanisms and their repercussions on the show. Theatrical The current research was divided into four chapters, namely (Chapter One - Methodology), which identified the research problem in the following question: What are the production mechanisms and their implicatio

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue May 20 2008
Journal Name
Journal Of Planner And Development
Estimating Water Quality from Satellite Image and Reflectance Data
...Show More Authors

The useful of remote sensing techniques in Environmental Engineering and another science is to save time, Coast and efforts, also to collect more accurate information under monitoring mechanism. In this research a number of statistical models were used for determining the best relationships between each water quality parameter and the mean reflectance values generated for different channels of radiometer operate simulated to the thematic Mappar satellite image. Among these models are the regression models which enable us to as certain and utilize a relation between a variable of interest. Called a dependent variable; and one or more independent variables

View Publication Preview PDF
Publication Date
Sun Jan 24 2016
Journal Name
Al-academy
Contemporary Sculpture vision and concept: محمد عبد الحسين يوسف
...Show More Authors

The research is divided into three chapters, the first of them to the research problem and its importance and its purpose and its limits, while the second chapter review of contemporary sculpture as a vision and concept, The third chapter came to view the most important results reached by the search.

 

View Publication Preview PDF
Crossref
Publication Date
Wed Mar 16 2022
Journal Name
Journal Of Educational And Psychological Researches
Agreeableness and Its Relation with Orientation towards Voluntary Work
...Show More Authors

 

The current study aims to identify agreeableness and orientation towards voluntary work of officials in public facilities, as well as to identify the nature of the correlation between agreeableness and orientation towards voluntary work of officials in public facilities. To achieve the aims of the research, the researchers designed the agreeableness scale, which consists of (28) items in its final form. The researchers also built a scale of orientation towards voluntary work, which consists of (29) items in its final form. Psychometric properties of validity and reliability of the two scales were extracted in various ways. The researcher applied the two scales on a sample of (400) officials, the results indicated that the

... Show More
View Publication Preview PDF
Publication Date
Mon Jan 01 2024
Journal Name
Malaysian Journal Of Nursing
Relationship between Cigarette Smoking and Anxiety Level among Nurses
...Show More Authors

Background: This study aims to determine whether cigarette smoking and anxiety degrees are related among nurses. Methods: A correlation design study was conducted at Baquba Teaching Hospital in Diyala Governorate, and the study period extended from September 10th, 2023, to January 28th, 2024. A nonprobability purposive sample was used to include 200 nurses working at Baquba Teaching Hospital, Iraq. Data were collected using a self-administered questionnaire from January 10th to February 7th, 2024. There were two components to the study instruments. Initially, the demographic sheet contained the individuals' sociodemographic data. The Taylor manifest anxiety scale is included in the second section. The collected data were analyzed us

... Show More
View Publication
Scopus (11)
Crossref (12)
Scopus Crossref
Publication Date
Fri Dec 01 2023
Journal Name
Alexandria Engineering Journal
A new tilted aerial robotic platform: Modeling and control
...Show More Authors

View Publication
Scopus (4)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Sat Dec 02 2017
Journal Name
Al-khwarizmi Engineering Journal
Speech Signal Compression Using Wavelet And Linear Predictive Coding
...Show More Authors

A new algorithm is proposed to compress speech signals using wavelet transform and linear predictive coding. Signal compression based on the concept of selecting a small number of approximation coefficients after they are compressed by the wavelet decomposition (Haar and db4) at a suitable chosen level and ignored details coefficients, and then approximation coefficients are windowed by a rectangular window and fed to the linear predictor. Levinson Durbin algorithm is used to compute LP coefficients, reflection coefficients and predictor error. The compress files contain LP coefficients and previous sample. These files are very small in size compared to the size of the original signals. Compression ratio is calculated from the size of th

... Show More
View Publication Preview PDF
Publication Date
Wed Apr 28 2021
Journal Name
2021 1st Babylon International Conference On Information Technology And Science (bicits)
Enhanced Twitter Community Detection using Node Content and Attributes
...Show More Authors

View Publication
Scopus (3)
Crossref (2)
Scopus Crossref