International Journal of Innovative Research and Scientific Studies

Gemstone manufacturing in the Arab scientific heritage from the Umayyad Era to the end of the Mamlūk Era (41-923 AH/ 662-1517AD): A cultural historical study

2026-06-29T09:27:31-05:00

This research investigates the advanced experimental methodologies developed by Arabic chemists (8th-14th Calendar centuries) for the synthesis and imitation of gemstones, with a primary focus on the corpora of Jābir ibn Ḥayyān [1]. Diverging from traditional historiography that often relegates these works to the realm of allegorical alchemy, this study provides evidence of early "materials engineering" based on a sophisticated understanding of the optical and mechanical properties of inorganic substances. By analyzing historical recipes through the lens of modern solid-state chemistry, the paper reveals Arabic pioneering in four technical domains: First, refractive index tuning is done through the strategic incorporation of lead oxides into silicate glass matrices in order to enhance optical dispersion. Second, the management of redox potentials to precisely control the chromatic spectra of transition metal ions such as copper, iron, and manganese. Third, crystal growth via chemical vapor transport is evidenced by protocols involving the sublimation and condensation of arsenic sulfides to produce high-purity crystalline solids. Finally, colloidal and substrate engineering is utilized in order to plaster calcium-based carriers and organic binders to stabilize organometallic pigments. The findings demonstrate that these protocols functioned as "Standard Operating Procedures" (SOPs) aimed at engineering synthetic alternatives that replicate the specific gravity, hardness, and refractive indices of natural rubies, emeralds, and lapis lazuli. By achieving these objectives, the study contributes to a significant re-evaluation of the history of materials science, positioning medieval Arabic chemistry as a direct precursor to modern glass technology and solid-state physics.

A study on a hydrogen injection control method for fuel cell engines based on proportional valve polling

2026-07-06T11:35:26-05:00

As the core component of fuel cell engine hydrogen supply systems, hydrogen injection solenoid valves suffer from high switching frequency, excessive power consumption and shortened service life under traditional equal-distribution control, which raises system failure risks and maintenance costs. To solve these problems, this paper puts forward a polling control strategy based on PI closed-loop pressure regulation. The stack inlet hydrogen pressure is sampled in real time to calculate the overall hydrogen injection duty cycle, which is evenly assigned to six solenoid valves via sequential allocation and cyclic rotation to balance valve workload and cut single-valve actuation frequency and heat loss. Co-simulation of Simulink and AMESim is conducted to compare three control modes, and a durability test bench is built for experimental validation. The Parker model is adopted to evaluate valve life attenuation. Simulation and test results reveal that the proposed polling method effectively suppresses hydrogen pressure fluctuation under low-flow conditions and improves control accuracy. It reduces valve switching times, power consumption and operating temperature, slowing insulation and seal aging. Durability tests show its first-failure time and total service life exceed the equal-distribution mode by over 2.5 times with fewer faulty valves. This strategy optimizes pressure control and component durability, offering great engineering application value for long-life commercial fuel cell vehicles.

Can strategic sourcing drive supply chain agility? A field investigation

2026-07-06T23:31:26-05:00

This study examines at how supply chain agility (SCA), which is evaluated by flexibility, speed, responsiveness, and efficiency in commercial organizations, is affected by strategic sourcing (SR), which is represented by internal integration, supplier development, information exchange, and strategic purchasing. used SmartPLS 4 for structural equation modeling (SEM) with a sample of 166 participants that included managers from supply and procurement departments in several Arab nations. The study's findings showed that supply chain agility was significantly impacted by strategic sourcing. Findings showed that every aspect of supply chain agility was highly impacted by every aspect of strategic sourcing. Both supply chain agility and strategic sourcing attracted a lot of interest from commercial businesses. To increase supply chain speed and efficiency, the study suggests investing in digital technologies, strengthening internal cross-departmental integration, putting supplier development programs into place, and improving information-sharing mechanisms. The study recommends broadening the scope to include other economic sectors and investigating moderating factors like organizational culture and digital transformation for future research.

The mediating effect of organizational capabilities between sustainable leadership and strategic success in Yemeni private universities

2026-07-07T23:41:57-05:00

The study aimed to identify the mediating effect of organizational capabilities between sustainable leadership and strategic success in Yemeni private universities. Background Problem: In an era of accelerating technological change and intense global competition among universities, this study sheds light on the mediating role of organizational capabilities in the relationship between sustainable leadership and strategic success in Yemeni private universities. The novelty of this study lies in addressing a research gap by examining the mediating role of organizational capabilities in the relationship between sustainable leadership and strategic success. Research Methods: A quantitative approach was employed using a structured questionnaire distributed to 304 stratified, randomly selected employees across different administrative levels in 13 private universities in Yemen. Data were analyzed using SPSS-27 and AMOS-24, including structural equation modeling. Findings: The results reveal a significant impact of sustainable leadership on both organizational capabilities and strategic success. Furthermore, organizational capabilities were found to partially mediate the relationship between sustainable leadership and strategic success. The findings highlight the importance of sustainable leadership practices in building organizational capabilities that, in turn, contribute to achieving strategic success. This suggests that university leaders should invest in leadership strategies that foster long-term capacity building and institutional development.