Arabian Journal of Chemistry最新文献

{"title":"Study on preparation and performance of bagasse/sodium carboxymethyl cellulose gel for inhibiting coal spontaneous combustion","authors":"Xiaowei Geng ,&nbsp;Yuanyuan Feng ,&nbsp;Yinhui Wang ,&nbsp;Hemeng Zhang ,&nbsp;Yujiao Liu ,&nbsp;Ke Gao","doi":"10.1016/j.arabjc.2024.105991","DOIUrl":"10.1016/j.arabjc.2024.105991","url":null,"abstract":"<div><div>In order to effectively prevent and control coal spontaneous combustion and improve the safety of coal mining, bagasse carboxymethy cellulose (BCC) prepared from bagasse (BS) and sodium carboxymethyl cellulose (CMC) were used as the substrates. A gel (BCC-CMC) for inhibiting coal spontaneous combustion was prepared using a chemical crosslinking method involving zirconium citrate crosslinking and glucono-delta-lactone (GDL) modification. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy were utilized to characterize both the crystal and molecular structure of bagasse and its derived bagasse carboxymethyl cellulose. The results indicated that new carboxymethyl groups were introduced into bagasse during the treatment, facilitating the successful extraction and preparation of sodium carboxymethyl cellulose. The results of viscosity and bonding tests demonstrated that the concentration and dosage of CMC had the most significant influence on the gel viscosity, which remained higher and more stable at room temperature. The coal bonded by the gel coal mixture can effectively seal surface cracks, with a bonding degree of up to 70.72 %. TG-DTG, temperature-programmed oxidation experiment and FTIR analyses revealed that, compared to raw coal, coal samples treated with gel exhibited improved stability, fewer active groups, and fewer oxygen-containing functional groups, effectively inhibiting coal’s low temperature oxidation and reducing the risk of spontaneous combustion. The gel is environmentally friendly, cost-effective, and exhibits good flame retardant properties. This study is of great significance for preventing and controlling coal spontaneous combustion, effectively ensuring the safe production of coal resources and the safety of mine workers, achieving the green sustainable development of the mine.</div></div>","PeriodicalId":249,"journal":{"name":"Arabian Journal of Chemistry","volume":"17 11","pages":"Article 105991"},"PeriodicalIF":5.3,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142359675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Machine learning approaches in designing anti-HIV nitroimidazoles: 2D/3D QSAR, kNN-MFA, docking, dynamics, PCA analysis and MMGBSA studies","authors":"Momin Ziyaul-Haque ,&nbsp;Rashid Ayub ,&nbsp;Mohd Usman Mohd Siddique ,&nbsp;Amit Gangwal ,&nbsp;Azim Ansari ,&nbsp;Mudassar Shahid ,&nbsp;Yogeeta O. Agrawal ,&nbsp;Tasneem Khan","doi":"10.1016/j.arabjc.2024.105995","DOIUrl":"10.1016/j.arabjc.2024.105995","url":null,"abstract":"<div><div>In this study, newly synthesized 20 nitroimidazole derivatives were subjected to 2D and 3D Quantitative Structure-Activity Relationship (QSAR) study to investigate their anti-HIV activity against both ROD and IIIB strains. Later, proposed hypothesis was virtually proved by further <em>in-silico</em> studies. In statistically significant 2D-QSAR models r² values for IIIB strains 0.9241 and for ROD strains 0.9412 with corresponding q² values of 0.7706 and 0.8299, were obtained, respectively. Different models were constructed using three different kNN-MFA 3D QSAR approaches such as SW-FB, SA score, and GA. By using the generated hypothesis, newer analogues of nitroimidazole derivatives was designed and molecular modelling studies were conducted to prove the hypothesis. The three molecules were displayed the good docking scores compared to the reference molecule. The stabilities of docked complexes were analyzed by MD simulations and MMGB/SA calculations. These results offer insightful design guidance for novel anti-HIV compounds synthesis and suggest interesting directions for future pharmaceutical research.</div></div>","PeriodicalId":249,"journal":{"name":"Arabian Journal of Chemistry","volume":"17 11","pages":"Article 105995"},"PeriodicalIF":5.3,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142359677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fast thermo-responsive thermoset self-healing polymers based on bio-derived Benzoxazine/Epoxidized castor oil copolymers for coating applications","authors":"Phattarin Mora ,&nbsp;Sarawut Rimdusit ,&nbsp;Chanchira Jubsilp","doi":"10.1016/j.arabjc.2024.106005","DOIUrl":"10.1016/j.arabjc.2024.106005","url":null,"abstract":"<div><div>This work emphasized on development of a novel bio-derived self-healing copolymer fabricated from benzoxazine and epoxy resins by varying weight ratios. The bio-derived benzoxazine (E-fa) acted as a healing agent was copolymerized with bio-derived epoxy resin namely epoxidized castor oil (ECO). Three main essential properties of the developed copolymer were systematically investigated: thermal property, mechanical property, and self-healing capacity. The numerical simulation was also used to study and predict the ability of roof coatings based on the developed copolymers. The results showed that the reversible crosslinking reaction occurred and resulted in state transition of the copolymers. The mechanical property i.e., tensile strength and peel strength to stainless steel substrate, were substantially improved with the incorporation of ECO. The increase in E-fa contents can enhance the thermos-responsive healing performance of the copolymers up to 93% via reversible reactions with rapid surface damage healed within 2 min. Furthermore, the experimental and numerical results revealed that the thermo-responsive thermoset self-healing bio-derived benzoxazine/epoxy copolymers have a potential use in coating applications required fast self-healing performance and good mechanical properties.</div></div>","PeriodicalId":249,"journal":{"name":"Arabian Journal of Chemistry","volume":"17 11","pages":"Article 106005"},"PeriodicalIF":5.3,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1878535224004076/pdfft?md5=3de23f7b1b2692a14451d9bf3a933bc5&pid=1-s2.0-S1878535224004076-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142314266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pyroelectric field drived photocatalysis by ZnFe2O4/NaNbO3 heterojunction for dye degradation through integration of solar and thermal energy","authors":"Di Zhou ,&nbsp;Xiaoju Zhou ,&nbsp;Zhenglong Hu ,&nbsp;Lili Zheng ,&nbsp;Yu Tian ,&nbsp;Yafang Tu ,&nbsp;Chunbo Hua ,&nbsp;Li Xue ,&nbsp;Juan Xiong","doi":"10.1016/j.arabjc.2024.105996","DOIUrl":"10.1016/j.arabjc.2024.105996","url":null,"abstract":"<div><p>A novel composite of ZnFe₂O₄/NaNbO₃ (ZFO/NNO) nanorods with a p-n heterojunction structure was successfully synthesized via the hydrothermal method. The NNO nanorods were heated in situ using the photothermal effect of ZFO and subsequently cooled to room temperature, creating a cyclic heating and cooling process for ZFO/NNO. The catalytic activity of the resulting nanorods was assessed through the degradation of Rhodamine B, reaching 98% degradation efficiency after 180 min, attributed to the synergistic effect of pyrocatalysis and photocatalysis. Compared with NNO and ZFO individually, the enhanced performance of ZFO/NNO can be attributed to several synergistic factors, including the expanded spectral range of light absorption for ZFO, the establishment of the built-in electric field of the p-n junction between ZFO and NNO, and the NNO pyroelectric effect that further improved the charge transfer efficiency. Superoxide radicals and holes generated from photo-induced electrons were identified as the active species. Hydroxyl radicals generated from pyroelectrically-induced charge also participated in catalytic reaction. The combined effect of pyroelectric and photocatalytic processes could significantly improve the coupled pyro-photocatalytic reaction for pyroelectric semiconductor heterostructure, enabling the utilization of multiple energy sources, including solar and thermal energy.</p></div>","PeriodicalId":249,"journal":{"name":"Arabian Journal of Chemistry","volume":"17 11","pages":"Article 105996"},"PeriodicalIF":5.3,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1878535224003988/pdfft?md5=f29b09840e3044b4925fb9c07c5847c0&pid=1-s2.0-S1878535224003988-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142270764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fabrication of boron nitride/copper oxide@multi-walled carbon nanotubes composites for enhancing heat transfer and photothermal conversion of phase change materials","authors":"Weifang Han ,&nbsp;Deyi Liu ,&nbsp;Guoliang Wang ,&nbsp;Suliang Li ,&nbsp;En You ,&nbsp;Zhengfeng Jia ,&nbsp;Yuchao Li","doi":"10.1016/j.arabjc.2024.105997","DOIUrl":"10.1016/j.arabjc.2024.105997","url":null,"abstract":"<div><p>To realize the efficient storage and conversion of solar energy by phase change materials (PCMs), low photothermal conversion efficiency and poor heat transfer performance remain great challenges. Herein, polyethylene glycol (PEG)-based composite PCMs with excellent photothermal conversion performance and exceptional thermal management capability were obtained by using boron nitride/copper oxide@multi-walled carbon nanotubes (BN/CuO@MWCNTs) as the thermal conductive and photothermal conversion enhancement fillers. The results indicate that owing to the bridging effect, the introduction of CuO and MWCNTs on the BN surface can construct additional heat transfer paths, resulting in a high thermal conductivity of up to 2.35 W/(m·K) for the as-prepared PEG/BN/CuO@MWCNTs composite, which is about 9-folds enhancement than pristine PEG. Simultaneously, the supercooling degree of PEG in PEG/BN/CuO@MWCNTs is effectively suppressed due to the synergistic nucleation effect of BN, CuO and MWCNTs. Additionally, the PEG/BN/CuO@MWCNTs composites not only exhibit a high latent-heat capacity of 154.5 J/g and a high photothermal conversion efficiency of 92.2 %, but also show favorable shape stability and durable reliability. This work offers a workable solution for the synergistic enhancement of photothermal conversion and thermal management, which can effectively promote the practical application in solar energy conversion and storage.</p></div>","PeriodicalId":249,"journal":{"name":"Arabian Journal of Chemistry","volume":"17 11","pages":"Article 105997"},"PeriodicalIF":5.3,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S187853522400399X/pdfft?md5=5803f172eeea4264663d5729d6233e3a&pid=1-s2.0-S187853522400399X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142271510","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pesticide residues and associated health effects in marketed fruits in Saudi Arabia","authors":"Majed S. Alokail ,&nbsp;Manal E.A. Elhalwagy ,&nbsp;Sherif H. Abd-Alrahman ,&nbsp;Abdullah M. Alnaami ,&nbsp;Syed D. Hussain ,&nbsp;Osama E. Amer ,&nbsp;Shaun Sabico ,&nbsp;Nasser M. Al-Daghri","doi":"10.1016/j.arabjc.2024.105993","DOIUrl":"10.1016/j.arabjc.2024.105993","url":null,"abstract":"<div><h3>Aim</h3><p>This study evaluated the pesticide residues in some fruits collected from different markets in Saudi Arabia (SA) and determined potential health risks associated with them.</p></div><div><h3>Methods</h3><p>Concentrations of pesticide residues in 12 types of fruits from local markets in SA from 2020 to 2022 were collected and evaluated. Multiple residue extraction method QuEChERS followed by LC-MS/MS and GC–MS/MS, were used to analyze 161 samples<strong>.</strong></p></div><div><h3>Results</h3><p>Only 10 out of 161 samples (6.2 %) were free of pesticides. A total of 132 (87.4 %) pesticide residues were below MRLs, with 19 (12 %) of samples exceeding MRLs. Detected pesticide residues belonged to different chemical classes of pesticides including organophosphates, pyrethroids, organochlorines, neonicotinoids and fungicides. Risk assessment of human exposure to pesticides via the intake of the fruit types was performed. Hazard index (HI) for most fruit types were found to be less than 1. Oranges, grapes and pomegranates were the most consumed fruit types (31.6 g/day,15.8 g/day,10.8 g/day) and were contaminated with pesticide residues. Fluopyram, imazalil, chlorpyrifos, finamiphos and indoxacarb had HIs (1.32, 2.76,3.6,3.6,1.5) showed high risk index suggesting risk for systemic toxicity in consumers dependent on the amount of consumption.</p></div><div><h3>Conclusion</h3><p>In summary, high detection rate of pesticide residues was found in different fruits sold in local markets in SA. Regular biomonitoring programs for food crops in SA markets should be enforced, particularly in identified crops with His &gt;1 to increase food safety within the SA community.</p></div>","PeriodicalId":249,"journal":{"name":"Arabian Journal of Chemistry","volume":"17 11","pages":"Article 105993"},"PeriodicalIF":5.3,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1878535224003952/pdfft?md5=19c4e5e93d62d9434b000e393653c070&pid=1-s2.0-S1878535224003952-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142271509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced sonophoto-catalytic and adsorption capabilities of Fe3O4@MC/MWCNT-CuO/Ag for petrochemical organic pollutants degradation from industrial process streams","authors":"Saeed Rajabi ,&nbsp;Hassan Hashemi ,&nbsp;Mohammad Reza Samaei ,&nbsp;Alireza Nasiri ,&nbsp;Abooalfazl Azhdarpoor ,&nbsp;Saeed Yousefinejad","doi":"10.1016/j.arabjc.2024.105994","DOIUrl":"10.1016/j.arabjc.2024.105994","url":null,"abstract":"<div><p>To address the problem of petrochemical organic pollutants in water, specifically monoethylene glycol (MEG) present in industrial process streams, in this research, we synthesized and evaluated a multifunctional nanocomposite, Fe₃O₄@MC/MWCNT-CuO/Ag. The nanocomposite was produced by combining magnetic Fe₃O₄ nanoparticles, methylcellulose (MC), multi-walled carbon nanotubes (MWCNTs), and CuO/Ag nanoparticles by an integrated synthesis process. A consistent dispersion of nanoparticles, with diameters ranging from 30-40 nm, was discovered by FESEM analysis, showing effective integration without aggregation. Effective synthesis was demonstrated by well-doped and evenly dispersed CuO and Ag nanoparticles. Functional groups that improve electrostatic interactions with contaminants hence enhancing catalytic performance and adsorption efficiency, were validated by FTIR analysis. XRD indicated an unchanged crystal structure with an average crystallite size of 8.67 nm. The anticipated elemental composition was verified by EDS &amp; mapping. A VSM study revealed magnetic characteristics (9.33 emu/g) that simplify nanocomposite separation and reuse. TGA proved thermal stability to be up to 600 °C. A BET study showed a highly specific surface area of 67.661 m²/g, enhancing adsorption. According to DRS and PL studies, the bandgap was lowered by 1.31 eV, which led to better optical absorption. The nanocomposite exhibited notable MEG removal efficiency, with 72 % in adsorption, 65 % in photocatalysis, and 56 % in sonocatalysis. This makes it a promising alternative for the remediation of organic pollutants in water treatment.</p></div>","PeriodicalId":249,"journal":{"name":"Arabian Journal of Chemistry","volume":"17 11","pages":"Article 105994"},"PeriodicalIF":5.3,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1878535224003964/pdfft?md5=452fdd95ea9d7a2ae6d8b88728d92735&pid=1-s2.0-S1878535224003964-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142270763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electrodeposited zinc oxide nanoparticles: Synthesis, characterization, and anti-cervical cancer effects","authors":"Yingying Chen ,&nbsp;Xinxin You ,&nbsp;Liya Ye ,&nbsp;Shuangshuang Mei ,&nbsp;Junhui Yu ,&nbsp;Youyou Xie ,&nbsp;Kai Wang ,&nbsp;Xing Chen","doi":"10.1016/j.arabjc.2024.105992","DOIUrl":"10.1016/j.arabjc.2024.105992","url":null,"abstract":"<div><div>In the present study, zinc oxide nanoparticles (ZnO NPs) were synthesized via the electrodeposition method and characterized. Then, the anticancer effects of ZnO NPs against cervical cancer HeLa cells were assessed by cell viability, oxidative stress, caspase activity, qRT-PCR, MMP, and ELISA assays. XRD analysis revealed the hexagonal wurtzite phase of ZnO. SEM image of ZnO NPs showed the homogeneous spherical/hexagonal-like structures of ZnO NPs, while TEM imaging revealed the successful synthesis of ZnO NPs with an average diameter of about 8 nm. The UV–vis absorption spectrum of ZnO NPs showed a characteristic absorption band around the wavelength of 368 nm with a band gap energy (Eg) of 3.36 eV. DLS study displayed that the obtained particle size of ZnO NPs has an average size of 29.24 nm and an average zeta potential value of −19 mV. Additionally, cellular findings indicated that the proliferation of cervical cancer HeLa cells was markedly mitigated after incubation with ZnO NPs at different concentrations of 10, 50 and 100 µg/ml, however, these concentrations were not able to trigger an apparent cytotoxic effect on HUVEC non-malignant cells. Also, it was detected that ZnO NPs led to overexpression of Bax/ Bcl-2, caspase-9/-3 genes, increased level of caspase-9/-3 activity, overproduction of MDA level, inhibition of SOD and CAT activity and reduction of GSH content, MMP collapse, and upregulation of cytoplasmic cytochrome <em>c</em> release. In general, these findings suggested that electrodeposited synthesized ZnO NPs can induce anticancer effects in cervical cancer HeLa cells through the mitochondrial-mediated apoptosis signaling pathway.</div></div>","PeriodicalId":249,"journal":{"name":"Arabian Journal of Chemistry","volume":"17 11","pages":"Article 105992"},"PeriodicalIF":5.3,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142322994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bioinformatical and experimental validation on EFNA5 biomarker for pancreatic cancer","authors":"Ze Hua ,&nbsp;Rongshuang Zhao ,&nbsp;Wenbo Guan ,&nbsp;Siya Liu ,&nbsp;Jurui Ge ,&nbsp;Yiran Zhang ,&nbsp;Suliman Khan ,&nbsp;Zhenjie Pan ,&nbsp;Jian Wang","doi":"10.1016/j.arabjc.2024.105990","DOIUrl":"10.1016/j.arabjc.2024.105990","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Pancreatic cancer is one of the most aggressive malignancies in the digestive system, characterized by vague early symptoms and rapid disease progression. Currently, treatment options for pancreatic cancer are limited, with unsatisfactory outcomes and poor prognosis, as the overall 5-year survival rate is less than 10%. Therefore, it is crucial to identify new biomarkers for pancreatic cancer.&lt;/div&gt;&lt;div&gt;We analyzed the differential expression of EFNA5 at the mRNA level using data from the TCGA, GTEX, and GEO databases, followed by validation of EFNA5 protein expression differences through immunohistochemistry. Kaplan-Meier survival analysis and Cox regression analysis were used to explore the prognostic value of EFNA5. KEGG, GO enrichment analyses, and GSEA were employed to predict the biological functions of EFNA5. Bioinformatics algorithms were utilized to analyze the impact of EFNA5 on drug sensitivity, immune cell infiltration, and tumor mutational burden. Finally, we conducted cell phenotype experiments to investigate the effects of EFNA5 on the proliferation, migration, and invasion of pancreatic cancer cells. Bioinformatics data showed that the mRNA level of EFNA5 was higher in pancreatic cancer tissues compared to normal tissues. Immunohistochemistry experiments confirmed that the protein expression level of EFNA5 was significantly higher in pancreatic cancer tissues (n = 19) than in adjacent normal tissues (n = 19). Survival analysis indicated that the overall survival (OS) and progression-free survival (PFS) were worse in the high EFNA5 expression group compared to the low expression group. Univariate and multivariate Cox regression analyses demonstrated that EFNA5 is a risk factor affecting the prognosis of pancreatic cancer patients. KEGG pathway enrichment analysis revealed that differentially expressed genes (DEGs) between high and low EFNA5 expression groups were primarily enriched in pathways such as PI3K/Akt, axon guidance, and focal adhesion. GO enrichment analysis showed that DEGs were mainly associated with functions like epidermis development, cell adhesion, and intercellular junctions. Immune cell infiltration analysis found that EFNA5 expression was correlated with the infiltration levels of various immune cells. The tumor mutational burden was higher in the high EFNA5 expression group compared to the low expression group. Drug sensitivity analysis indicated that the high EFNA5 expression group had lower sensitivity to several commonly used chemotherapy drugs for pancreatic cancer. Cellular experiments demonstrated that knocking down EFNA5 inhibited the proliferation, invasion, and migration of pancreatic cancer cells. EFNA5 is overexpressed in pancreatic cancer tissues, and its high expression is associated with poor prognosis in pancreatic cancer patients. Downregulation of EFNA5 reduces the proliferation, migration, and invasion capabilities of the pancreatic cancer cell line BxPC-3. EFNA5 is closely related to","PeriodicalId":249,"journal":{"name":"Arabian Journal of Chemistry","volume":"17 11","pages":"Article 105990"},"PeriodicalIF":5.3,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142359676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Copolymerization of ethylene and isoprene initiated by metallocene catalyst","authors":"Amjad Ali ,&nbsp;Muhammad Nadeem ,&nbsp;Ahmad Naveed ,&nbsp;Jamile Mohammadi Moradian ,&nbsp;Syed Najeeb-Uz-Zaman Haider ,&nbsp;Shahid Khan ,&nbsp;Adnan Murad Bhayo ,&nbsp;Jianwei Lu ,&nbsp;Rai Nauman Ali ,&nbsp;Naushad Ahmad ,&nbsp;Fan Zhiqiang ,&nbsp;Li Guo","doi":"10.1016/j.arabjc.2024.105989","DOIUrl":"10.1016/j.arabjc.2024.105989","url":null,"abstract":"<div><p>In this study, we explore the dynamic nature of metallocene catalysts during ethylene/isoprene E/IP) copolymerization, with a focus on the influence of various reaction parameters. Challenges, why do olefinic catalysts show lower activity and molecular weight (Mw) at higher temperatures and low activity with higher diene content? Firstly, we investigate the observed phenomena of decreased catalyst activity and Mw at elevated temperatures using 1.25 μmole of the metallocene. Notably, a substantial increase in active sites from 30 °C to 40 °C, reaching a peak of 89 %. Surprisingly, further temperature increments lead to a noticeable decline in active sites. At 30 °C, the active site primarily engages in the insertion of IP through 3,4 connections, with no detectable <em>cis</em>-1,4 or <em>trans</em>-1,4 connections, which suggests a lack of stereoselectivity at this temperature. At 40–50°C, <em>cis</em>/<em>trans</em>-1,4 connections and active sites are approaching a higher level. This implies a reduction in chain transfer reactions, making catalytic active sites more favorable to <em>cis</em>/<em>trans</em>-1,4 connections. Secondly, we observe a remarkable impact of IP concentration in the E/IP copolymers, active centers, and activity show stability when the amount of IP was 0.116–0.48 mol/L and then started to decline when the amount of IP 0.96 mol/L, indicating a threshold beyond which deactivation occurs. Increasing IP concentration not only reduces activity and active sites but also fails to reactivate dormant polyethylene sites. The Mw and active centers of copolymers progressively decrease with elevated IP concentration, suggesting a faster chain transfer reaction with IP compared to E.</p></div>","PeriodicalId":249,"journal":{"name":"Arabian Journal of Chemistry","volume":"17 11","pages":"Article 105989"},"PeriodicalIF":5.3,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1878535224003915/pdfft?md5=2c1c09873f8b5dc5cb05b8e8838db543&pid=1-s2.0-S1878535224003915-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142238659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}