---

Research subject:
As a low price biomass, rice husk is able to accumulate a large amount of silica in its texture. The process for extracting this silica is greener than the conventional ones. The present research addresses the effects of the different process parameters on amorphous silica extraction from rice husk through a precipitation method.
Research approach
In the extraction process, first the rice husk was burned in the open air and then turned into white ash in an electric furnace. This ash was converted into sodium silicate solution using NaOH, and finally the silica was precipitated from this solution by sulfuric acid. The effect of solid to solvent ratio, the duration of the alkaline dissolution step as well as the pH and temperature of acid precipitation step have been investigated. Moreover, a special application of the amorphous silica in rubber industry was also investigated.
Main results
The results showed that a low solid to solvent ratio at the alkaline dissolution stage as well as an acidic pH along with a high precipitation temperature are required to obtain the highest production efficiency and to obtain high purity amorphous silica. The purity and chemistry of obtained silica were quite similar to commercial sample in the rubber industry; however, the surface area and pore volume of obtained silica was less than the commercial one. It was also found that prolonging the alkali dissolution step slightly increases the production efficiency. The obtained silica exhibited very close performance to the commercial sample, in the rubber-to-fiber adhesion system (RFS). This indicates the high ability of precipitated silica to be replaced by commercial types, which are mainly produced by more cost-effective and less biocompatible processes.

---

The topic of Hyperbole has been taken into consideration in various sciences of Arabic language, but less has been taken into additional verb, especially in the Holy Qur'an. The abundance of Hyperbole in the Qur'an's additional verbs and the semantic delimitations of these sentences and the lack of sufficient attention by translators in translating them necessitates research and review of this subject. In the present research, through the descriptive-analytical method, the challenges of the concept of Hyperbole and its reversal in lower Quran additional verbs have been examined. The purpose of this research is to introduce these challenges and ultimately provide a more accurate translation of the Qur'an. According to the findings of this research, at least three major challenges in this regard can be identified: The multiplicity of meanings of third person verb and the glorification of more famous meanings, the interconnection of the two concepts of "plurality" and " Hyperbole", and mistake in identifying the subject of Hyperbole. Moreover, the study of sample verses in this study shows that the general Persian interpretations and translations have a weakness and inadequacy in the understanding and transference of the concept of Hyperbole of additional verbs in the Qur'an. In addition, the method of analyzing verses in this study reveals that it is not easy to distinguish between the implication of verbs on Hyperbole, and can not be understood solely by relying on the mere meaning of the terms and generalities contained in the mere books on this subject. Instead, it is necessary to interpret the text of the verses and analyze its space using the inner and outer metamorphosis in order to recognize the implication of Hyperbole in the additional verbs of the Qur'an.

---

Aims: This study aimed to determine the antibiotic resistance pattern of Pseudomonas aeruginosa clinical isolates and the frequency of blaSIM and blaAmpC genes in resistant strains.
Materials & Methods: In this cross-sectional study, 94 P. aeruginosa isolates were collected from the burn wards of Gilan province hospitals in 2018 and identified by biochemical methods. Strains producing β-lactamases and metallo-β-lactamases were detected by two methods: disk diffusion method and antibiotic resistance method in combination with disk diffusion method, respectively. The presence of blaSIM and blaAmpC genes in the resistant strains was investigated using PCR, and data analysis was performed.
Findings: Based on the obtained results, colistin was identified as the most effective antibiotic with a resistance rate of 27.7%, and the highest antibiotic resistance was observed against trimethoprim/sulfomethoxazole (83%). In the phenotypic test of 94 samples, 29 (30.9%) carbapenemase-producing isolates and 33 (35.1%) β-lactamase-producing isolates were identified. Based on the PCR results, among 44 (46.8%) samples containing β-lactamase and carbapenemase enzymes, the frequency of blaSIM gene was 9.1% (4 of 44, and 4.3% in all the studied isolates), and the frequency of blaAmpC gene was 15.9% (7 of 44, and 7.4% in the all studied isolates).
Conclusion: The results of this study indicated a high prevalence of drug resistance in clinical isolates of P. aeruginosa. In particular, there was an increasing rate of resistance to beta-lactam antibiotics, and the presence of MBL and ESBL associated genes was considerable, which limit the choice of suitable treatment for patients with severe infections.

 

---

Need analysis (NA) is one the important elements of the curriculum that tries to detect lacks, wants, necessities and the gap between the existing curriculum and developed curriculum. NA is a powerful tool that helps clarify and validate true needs. It enables educators and practitioners to shape the curriculum development that bases the content of language courses on the communication needs. This work analyzes the language lacks of the Arabic language and literature students of Iranian universities. The method of study is survey, and the research tool is questionnaire. The study sample is consisted of two groups of students and teachers. The method of data analysis is quantitative. The main question of this study is: “To what extend do students have problems in language skills” and “To what competence does problems belong?” The results showed that the students' language skills are above the average difficulty, and they have linguistic problems arising from the lack of communicative competence.

---

The psychological factors, relationships with colleagues and the culture of the target language, play an active role in academic achievement. The main issue of this study is to determine the psychometric properties of the scale of these factors in learning Arabic for Iranian students at the undergraduate level. This study used the mixed exploratory sequential design. The initial items were designed in the form of a qualitative research and semi-structured interviews with specialists in teaching the Arabic language and literature and experts in educational psychology. The final form which contains (83) of items was determined. To ensure its validity and reliability, a sample of (100) students at undergraduate level was conducted through the official virtual educational spaces and the sampling method. Results: (83) essential items were selected based on the Lawshe criterion with (CVR) above (0.6), and the total (CVI), by using software (SPSS), was equal to (0.83) which is acceptable. The internal reliability of the scale was calculated through Cronbach's alpha, and all values were higher than (0.8), which indicates the internal reliability of the scale factors. The (CR) and the (AVE) of the scale factors were higher than (0.8) and (0.5) which Shows the scale’s convergent validity. (CCV) indicates a significant relationship between scale factors and averages of the research sample. In total, the final scale has (32) items with (64.22) of the variance of the total scale. Accordingly, the scale has the appropriate psychometric properties to determine the essential factors that affecting the academic achievement.
1. Introduction
 The 1960s has viewed a major shift in epistemology. The components of academic success for foreign language learners are no longer only related to the cognitive skills, but also become closely related to the other aspects, such as the learner’s psychological aspect like the social personality, the relationship with his classmates, and the culture of the target language. The learner's mind is the method to express his or her emotions, and the learner who can express his thoughts and control his negative feelings, face difficulties, be flexible in the face of opposing ideas and different cultures, and manage time; He will be more successful than the other students.
Research Questions
1. What are the psychological and interpersonal factors affecting the academic success of students of the Arabic language and literature department at the undergraduate level?
2. Does the study tool have content validity and content validity index?
3. To what degree does the study tool have structural, convergent and concurrent criterion validity?
4. Is the study instrument sufficiently reliable?

2. Literature Review

 2-1. Academic achievement

Is one of the most important criteria for evaluating the performance of the language learner who qualifies him to enter the labor market, and to follow up his achievement at the higher levels. It was defined by Chaplin & Olds (1964), “the level of efficiency of achievement in educational work, and it can be determined by specific tests to evaluate students’ work.”. Based on the foregoing, academic achievement is the most important educational and scientific variable that is related to various factors such as the psychological and personal factors of learners, which differ from one individual to another.

2-2. Psychological Factors:

Among the most important psychological factors affecting academic achievement are personal factors: Academic vitality is an important component of a learner's personality; “Academic vitality means the ability of successful students to face and overcome obstacles and academic challenges.” (Comerford et al.: 2015). Psychoeducational factors include academic self-efficacy, which includes cognitive and emotional support for friends, and communication styles with peers. Also, the relationships with others are manifested in assertiveness; “involves many things, including the expression of true feelings, the defense of legitimate rights, and the refusal of unreasonable demands.” (Rathus: 1998).

3. Methodology

 In this research, mixed exploratory sequential design was used. It is one of the methods that uses qualitative and quantitative measurement to collect and analyze data; That is, this method has the strengths of both qualitative and quantitative research at the same time (Berman, 2017, 1 and 5).

4. Results

The Factor Number	The Factor Name	correlation coefficient	Meaningful Level
1	effective communication with native speakers	0.372	0.001
2	The academic vitality	0.353	0.001
3	effective interpersonal communication	0.328	0.002
4	The problem-based learning	0.335	0.002
5	The academic self-efficacy	0.345	0.001
6	assertiveness	0.287	0.012
7	The emotional control	0.291	0.003

The factor of effective communication with native speakers with the expressions of common cultural aspects; Different cultural aspects; Familiarity with important issues in the target language community; The skill of empathy and avoiding misunderstood situations is of the utmost value. As a result, cultural factors are the most important factors in learning Arabic in Iran.

---

Simulation of the four degree of freedom parallel robot (Quattrotaar) is subjective of this paper. The mathematical model of the parallel robot is obtained too. The workspace is optimized for Non-singular kinematic type-2. Artificial Bees Colony algorithm and Particle Swarm Optimization algorithm as overall exploring algorithms are implemented and the results are compared to each other. Neglect of any intrinsic complexity of the optimization problem the results show the capability of both methods for this robot parameters design. Comparison of the results indicates the Particle Swarm Optimization algorithm runs faster than Artificial Bees Colony algorithm. The exploring volume consists of a plan with 500 mm x 500 mm dimension which moves in a vertical direction from 500 mm to 1000 mm. One of the important hints of the paper is a 90-degree rotation of end effector around vertical axis Z. This rotation is caused more flexibility and dexterity for the robot. A 3-D model of Quattrotaar parallel robot is created by Computer Aided Design software and finally, Quattrotaar is fabricated in Human and Robot Interaction Laboratory (Taarlab)

---

In the opinion of many specialists and teachers, there is lack of enough attention to the needs of the students and their learning styles in the Arabic language curriculum. Learning styles are important factors in the success of teaching. This study aimed at determining the learning styles of Arabic language and literature students in Iranian Universities. The method of study is survey, and the research tool is questionnaire. The study sample consists of two students in Arabic language and literature. The method of data analysis is quantitative. The main questions of this study are: A: What are the common learning styles of learners? and B: What are the preferred learning styles of learners?? The results indicate that analytical learning and authority-oriented learning are common learning styles of learners and communicative Learning and concrete learning are their favorite styles.  

---

The defectless microstructure of metal matrix composites, the uniform distribution of particles and their good properties are determined by the production parameters and the base material and reinforcement. In this study, high-energy planetary ball mill was used to fabricate Al6063-SiC composite powder. Aluminum chips were milled with different time and ball to powder weight ratio (BPR) in high energy planetary ball mill. The resulting powder was mechanically alloyed by adding different weight percentages of silicon carbide (SiC) and BPRs at different times. During the milling process under argon atmosphere, stearic acid was used as a process control agent (PCA) to prevent excessive cold welding and agglomeration of the powder. After mechanical alloying, the effect of alloying time, BPRs and weight percentage of silicon carbide, on the obtained composite powder were examined morphologically by particle size analysis (PSA), field emission scanning electron microscope (FESEM), and the fuzzy compounds by X-ray diffraction (XRD) spectroscopy. According to the X-ray diffraction pattern of the samples, grain size was calculated using the Williamson-Hall model. The results of mechanical milling and alloying process have shown that in short milling times with high BPRs composite powder with finer particle size could be achieved. Also, the presence of silicon carbide reinforcing particles accelerates the process of mechanical alloying and further reduces the particle size.