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Amphiphilic Carboxymethyl Cellulose Stearate for Pickering Emulsions and Antimicrobial Activity of Chrysanthemum Essential Oil
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作者 Mohamed El-Sakhawy Sally A.Abdel-Halim +2 位作者 Hebat-Allah S.Tohamy Hossam M.El-Masry Mona Mohamed AbdelMohsen 《Journal of Renewable Materials》 2025年第5期981-995,共15页
This study prepared and characterized amphiphilic carboxymethyl cellulose stearate(CMCS)recycled from sugarcane bagasse agro-waste(SB).The Fourier-transform infrared(FTIR)analysis confirmed cellulose,carboxymethyl cel... This study prepared and characterized amphiphilic carboxymethyl cellulose stearate(CMCS)recycled from sugarcane bagasse agro-waste(SB).The Fourier-transform infrared(FTIR)analysis confirmed cellulose,carboxymethyl cellulose(CMC),and CMCS structures,with CMCS showing increased H-bonding.X-ray diffraction analysis(XRD)revealed reduced crystallinity in CMC and CMCS.CMCS exhibited a hydrophobic nature but dispersed in water,enabling nanoemulsion formation.Optimal nanoemulsion was achieved with CMCS1,showing a particle size of 99 nm.Transmission electron microscopy(TEM)images revealed CMC’s honeycomb structure,transforming into spherical particles in CMCS1.Antimicrobial tests demonstrated strong activity of CMCS formulations against Escherichia coli and Staphylococcus aureus,with CMCS3 exhibiting the highest efficacy.These findings highlight the potential of CMCS-based nanoemulsions for antimicrobial applications and nanoemulsification. 展开更多
关键词 Carboxymethyl amphiphilic cellulose carboxymethyl cellulose-stearate chrysanthemum essential oil nano-emulsification pickering emulsion
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RankXLAN:An explainable ensemble-based machine learning framework for biomarker detection,therapeutic target identification,and classification using transcriptomic and epigenomic stomach cancer data
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作者 Kasmika Borah Himanish Shekhar Das +1 位作者 Mudassir Khan Saurav Mallik 《Medical Data Mining》 2026年第1期13-31,共19页
Background:Stomach cancer(SC)is one of the most lethal malignancies worldwide due to late-stage diagnosis and limited treatment.The transcriptomic,epigenomic,and proteomic,etc.,omics datasets generated by high-through... Background:Stomach cancer(SC)is one of the most lethal malignancies worldwide due to late-stage diagnosis and limited treatment.The transcriptomic,epigenomic,and proteomic,etc.,omics datasets generated by high-throughput sequencing technology have become prominent in biomedical research,and they reveal molecular aspects of cancer diagnosis and therapy.Despite the development of advanced sequencing technology,the presence of high-dimensionality in multi-omics data makes it challenging to interpret the data.Methods:In this study,we introduce RankXLAN,an explainable ensemble-based multi-omics framework that integrates feature selection(FS),ensemble learning,bioinformatics,and in-silico validation for robust biomarker detection,potential therapeutic drug-repurposing candidates’identification,and classification of SC.To enhance the interpretability of the model,we incorporated explainable artificial intelligence(SHapley Additive exPlanations analysis),as well as accuracy,precision,F1-score,recall,cross-validation,specificity,likelihood ratio(LR)+,LR−,and Youden index results.Results:The experimental results showed that the top four FS algorithms achieved improved results when applied to the ensemble learning classification model.The proposed ensemble model produced an area under the curve(AUC)score of 0.994 for gene expression,0.97 for methylation,and 0.96 for miRNA expression data.Through the integration of bioinformatics and ML approach of the transcriptomic and epigenomic multi-omics dataset,we identified potential marker genes,namely,UBE2D2,HPCAL4,IGHA1,DPT,and FN3K.In-silico molecular docking revealed a strong binding affinity between ANKRD13C and the FDA-approved drug Everolimus(binding affinity−10.1 kcal/mol),identifying ANKRD13C as a potential therapeutic drug-repurposing target for SC.Conclusion:The proposed framework RankXLAN outperforms other existing frameworks for serum biomarker identification,therapeutic target identification,and SC classification with multi-omics datasets. 展开更多
关键词 stomach cancer BIOINFORMATICS ensemble learning classifier BIOMARKER targets
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Emerging Role of 2D Materials in Photovoltaics:Efficiency Enhancement and Future Perspectives
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作者 Ghulam Dastgeer Muhammad Wajid Zulfiqar +7 位作者 Sobia Nisar Rimsha Zulfiqar Muhammad Imran Swagata Panchanan Subhajit Dutta Kamran Akbar Alberto Vomiero Zhiming Wang 《Nano-Micro Letters》 2026年第1期843-895,共53页
The growing global energy demand and worsening climate change highlight the urgent need for clean,efficient and sustainable energy solutions.Among emerging technologies,atomically thin two-dimensional(2D)materials off... The growing global energy demand and worsening climate change highlight the urgent need for clean,efficient and sustainable energy solutions.Among emerging technologies,atomically thin two-dimensional(2D)materials offer unique advantages in photovoltaics due to their tunable optoelectronic properties,high surface area and efficient charge transport capabilities.This review explores recent progress in photovoltaics incorporating 2D materials,focusing on their application as hole and electron transport layers to optimize bandgap alignment,enhance carrier mobility and improve chemical stability.A comprehensive analysis is presented on perovskite solar cells utilizing 2D materials,with a particular focus on strategies to enhance crystallization,passivate defects and improve overall cell efficiency.Additionally,the application of 2D materials in organic solar cells is examined,particularly for reducing recombination losses and enhancing charge extraction through work function modification.Their impact on dye-sensitized solar cells,including catalytic activity and counter electrode performance,is also explored.Finally,the review outlines key challenges,material limitations and performance metrics,offering insight into the future development of nextgeneration photovoltaic devices encouraged by 2D materials. 展开更多
关键词 2D materials Photovoltaics Interface engineering Work function tuning Energy harvesting
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Effects of transfected adenovirus-mediated transcription factor X-box binding protein 1 on hippocampal-derived neural stem cell proliferation and apoptosis under hypoxia 被引量:4
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作者 Ying Sha Baohua Liu +3 位作者 Qun Liu Lei Song Jia Fan Yong Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第13期981-986,共6页
BACKGROUND: Neural stem cell (NSC) survival is closely associated with cell apoptosis in ischemic-hypoxic regions following transplantation. Numerous studies have revealed that X-box binding protein 1 (XBP1) is a... BACKGROUND: Neural stem cell (NSC) survival is closely associated with cell apoptosis in ischemic-hypoxic regions following transplantation. Numerous studies have revealed that X-box binding protein 1 (XBP1) is a transcription factor during endoplasmic reticulum unfolded protein response and is essential for cell survival, differentiation, and anti-apoptotic effects. OBJECTIVE: To determine the effects of the XBP1 gene on NSC proliferation and apoptosis under hypoxic conditions following XBP1 gene transfection into rat embryonic hippocampal NSCs using recombinant adenovirus vector. DESIGN, TIME AND SETTING: In vitro experiments were performed at the Laboratory of Cell Biology of Jilin University and Laboratory of Proteomics, Department of Neurology, Jilin University China from September 2008 to November 2009. MATERIALS: Recombinant adenovirus package XBP1 gene and Ad-XBPl-enhanced green fluorescent protein plasmid (Guangzhou Easywin BioMed Technology, China), rabbit anti-XBP1 and its target gene estrogen receptor degradation-enhancing a-mannosidase-like protein (EDEM) glucose-regulated protein 78 (GRP78), anti-apoptotic molecule Bcl-2 and proapoptotic molecule Bax polyclonal antibody (Santa Cruz Biotechnology, Inc., Santa Cruz, CA, USA), and COCI2 (Sigma, St. Louis, MO, USA) were used in the present study. METHODS: Hippocampi from embryonic, Sprague Dawley rats on gestational day 16 were harvested for NSC isolation and cloning, followed by immunofluorescence for Nestin and sub-culturing. The recombinant adenovirus Ad-XBPl-enhanced green fluorescent protein plasmid was transfected into rat embryonic hippocampal NSCs, and then CoCl2 was applied to induce hypoxia. MAIN OUTCOME MEASURES: Cell quantification and 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide colorimetric assay were utilized to detect proliferation in XBPl-transfected NSCs for 7 consecutive days. Western blot assay was utilized to quantify XBP1 GRP78, EDEM, Bcl-2, and Bax expression. Flow cytometry was used to measure apoptosis. RESULTS: NSC proliferation was significantly enhanced following XBP1 gene transfection (P 〈 0.05). Under hypoxic conditions, GRP78, EDEM, and Bcl-2 levels increased, but Bax levels decreased. In addition, NSC apoptosis decreased following transfection (P 〈 0.05). CONCLUSION: The XBP1 gene was successfully transfected into rat embryonic hippocampal NSCs using a recombinant adenovirus vector. NSC proliferation following transfection, as well as anti-apoptotic effects under hypoxia, was significantly increased. 展开更多
关键词 X-box binding protein 1 HYPOXIA apoptosis endoplasmic reticulum stress neural stem cells transplantation nerve growth factor neural regeneration
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Identification and Quantification of Aerosol Polar Oxygenated Compounds Bearing Carboxylic or Hydroxyl Groups.1.Method Development 被引量:5
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作者 Jaoui M. Kleindienst T.E. +1 位作者 Lewandowski M. Edney E.O. 《天然产物研究与开发》 CAS CSCD 2004年第5期409-409,共1页
In this study,a new analytical technique was developed for the identification and quantification of multifunctional compounds containing simultaneously at least one hydroxyl or one carboxylic group,or both.This techni... In this study,a new analytical technique was developed for the identification and quantification of multifunctional compounds containing simultaneously at least one hydroxyl or one carboxylic group,or both.This technique is based on derivatizing first the carboxylic group(s) of the multifunctional compound using an alcohol (e.g.,methanol,1-butanol) in the presence of a relatively strong Lewisacid (BF3) as a catalyst.This esterification reaction quickly and quantitatively converts carboxylic acids to their ester forms.The second step is based on silylation of the ester compounds using bis(trimethylsilyl) trifluoroacetamide (BSTFA) as the derivatizing agent.For compounds bearing ketone groups in addition to carboxylic and hydroxyl groups,a third step was used based on PFBHA derivatizationof the carbonyls.Different parameters including temperature,reaction time,and effect due to artifacts were optimized.A GC/MS in EI and in methane-CI mode was used for the analysis of these compounds.The new approach was tested on a number of multifunctional compounds.The interpretation of their EI (70 eV) and CI mass spectra shows that critical information is gained leading to unambiguous identification of unknown compounds.For example,when derivatized only with BF3-methanol,their mass spectra comprise primary ions at m/z M ·+ +1,M ·+ +29,and M ·+ - 31 for compounds bearing only carboxylic groups and M ·+ +1,M ·+ +29,M ·+ -31,and M ·+ -17 for those bearing hydroxyl andcarboxylic groups.However,when a second derivatization (BSTFA) was used,compounds bearing hydroxyl and carboxylic groups simultaneously show,in addition to the ions observed before,ions at m/z M ·+ +73,M ·+ -15,M ·+ -59,M ·+ -75,M ·+ -89,and 73.To the best of our knowledge,this technique describes systematically for the first time a method for identifying multifunctional oxygenated compounds containing simultaneously one or more hydroxyl and carboxylic acid groups. 展开更多
关键词 气溶胶 氧化物 生物化学 定量分析 参数
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APG: A novel python-based ArcGIS toolbox to generate absence-datasets for geospatial studies 被引量:4
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作者 Seyed Amir Naghibi Hossein Hashemi Biswajeet Pradhan 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第6期90-104,共15页
One important step in binary modeling of environmental problems is the generation of absence-datasets that are traditionally generated by random sampling and can undermine the quality of outputs.To solve this problem,... One important step in binary modeling of environmental problems is the generation of absence-datasets that are traditionally generated by random sampling and can undermine the quality of outputs.To solve this problem,this study develops the Absence Point Generation(APG)toolbox which is a Python-based ArcGIS toolbox for automated construction of absence-datasets for geospatial studies.The APG employs a frequency ratio analysis of four commonly used and important driving factors such as altitude,slope degree,topographic wetness index,and distance from rivers,and considers the presence locations buffer and density layers to define the low potential or susceptibility zones where absence-datasets are generated.To test the APG toolbox,we applied two benchmark algorithms of random forest(RF)and boosted regression trees(BRT)in a case study to investigate groundwater potential using three absence datasets i.e.,the APG,random,and selection of absence samples(SAS)toolbox.The BRT-APG and RF-APG had the area under receiver operating curve(AUC)values of 0.947 and 0.942,while BRT and RF had weaker performances with the SAS and Random datasets.This effect resulted in AUC improvements for BRT and RF by 7.2,and 9.7%from the Random dataset,and AUC improvements for BRT and RF by 6.1,and 5.4%from the SAS dataset,respectively.The APG also impacted the importance of the input factors and the pattern of the groundwater potential maps,which proves the importance of absence points in environmental binary issues.The proposed APG toolbox could be easily applied in other environmental hazards such as landslides,floods,and gully erosion,and land subsidence. 展开更多
关键词 Absence-dataset Classification Python Machine learning algorithms GIS Groundwater HYDROGEOLOGY
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Carboxylative Suzuki coupling reactions of benzyl chlorides with allyl pinacolborate catalyzed by palladium nanoparticles 被引量:4
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作者 Jian Sun Jiasheng Wang +5 位作者 Xiujuan Feng Yoshinori Yamamoto Abdulrahman I.Almansour Natarajan Arumugam Raju Suresh Kumar Ming Bao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第7期1258-1262,共5页
Palladium-catalyzed carboxylative Suzuki coupling reactions of benzyl chlorides with allyl pinacol-borate were successfully conducted in the absence of any extra ligand to produce β,γ-unsaturated esters in satisfact... Palladium-catalyzed carboxylative Suzuki coupling reactions of benzyl chlorides with allyl pinacol-borate were successfully conducted in the absence of any extra ligand to produce β,γ-unsaturated esters in satisfactory to good yields. The carboxylative Suzuki coupling reaction proceeded smooth-ly under mild conditions in the presence of palladium nanoparticles generated in situ through the formation of a π-benzylpalladium chloride intermediate. 展开更多
关键词 Palladium nanoparticles Carboxylative Suzuki coupling Carbon dioxide Benzyl chlorides Allyl pinacolborate
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Synthesis and Chemical Shifts Calculation of α-Acyloxycarboxamides Derived from Indane-1,2,3-trione by DFT and HF Methods 被引量:3
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作者 Hooriye Yahyaei Ali Reza Kazemizadeh Ali Ramazani 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第9期1346-1356,共11页
α-Acyloxycarboxamides are synthesized from three-component Passerini reaction between indane-1,2,3-trione, isocyanides, and thiophenecarboxylic acids in quantitative yields. The structures of the final products were ... α-Acyloxycarboxamides are synthesized from three-component Passerini reaction between indane-1,2,3-trione, isocyanides, and thiophenecarboxylic acids in quantitative yields. The structures of the final products were confirmed by IR, 1H and 13C NMR spectroscopy, mass spectrometry, and elemental analysis. The B3LYP/HF calculations for computation of 1H and 13C NMR chemical shifts have been carried out for the title compounds at the 6-311+G** and 6-311++G** basis set levels within GIAO and CSGT approaches. Predicted 1H and 13C NMR che-mical shifts have been assigned and compared with experimental 1H and 13C NMR spectra and they are supported each other. 展开更多
关键词 DFT HF NMR spectra Passerini reaction ISOCYANIDE
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2-(Sulfooxy)propane-1,2,3-tricarboxylic acid as novel and versatile catalyst for the formylation of alcohols and amines using ethyl formate under neat conditions 被引量:1
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作者 Arash Ghorbani-Choghamarani Ziba Akbaripanah 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第4期450-453,共4页
2-(Sulfooxy)propane-1,2,3-tricarboxylic acid(supported on silica gel) has been introduced as novel and green catalyst for the formylation of alcohols and amines with ethyl formate,as mild formylation agent,under n... 2-(Sulfooxy)propane-1,2,3-tricarboxylic acid(supported on silica gel) has been introduced as novel and green catalyst for the formylation of alcohols and amines with ethyl formate,as mild formylation agent,under neat conditions at room temperature. 展开更多
关键词 Alcohol Amine 2-(Sulfooxy)propane-1 2 3-tricarboxylic acid FORMYLATION Ethyl formate
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An efficient and mild carboxylation of multiwall carbon nanotubes using H_2O_2 in the presence of heteropolyacid 被引量:1
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作者 M.Z.Kassaee H.Zandi +1 位作者 J.Akbari E.Motamedi 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第4期470-473,共4页
A clean,fast,and facile oxidation of multiwalled carbon nanotubes(MWCNTs) by H_2O_2/heteropolyacid(H_3PW_(12)O_(40)) gave highly carboxylated MWCNTs under mild conditions,at a conveniently accessible temperatu... A clean,fast,and facile oxidation of multiwalled carbon nanotubes(MWCNTs) by H_2O_2/heteropolyacid(H_3PW_(12)O_(40)) gave highly carboxylated MWCNTs under mild conditions,at a conveniently accessible temperature.After an easy workup,the product was characterized by SEM,XRD,and FT-IR. 展开更多
关键词 Nanostructures OXIDES Chemical synthesis X-ray diffraction Infrared spectroscopy
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Facile synthesis of N-(arylsulfonyl)-4-ethoxy-5-oxo-2,5-dihydro-1H-pyrolle-2,3-dicarboxylates by one-pot three-component reaction 被引量:4
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作者 Hossein Anaraki-Ardakani Maziar Noei Afrooz Tabarzad 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第1期45-48,共4页
Three-component reaction of arylsulfonamides,dialkyl acetylenedicarboxylates,and ethyl chlorooxoacetate promoted by triphenylphosphine and triethylamine provides a sufficient route for the synthesis of dialkyl N-(ary... Three-component reaction of arylsulfonamides,dialkyl acetylenedicarboxylates,and ethyl chlorooxoacetate promoted by triphenylphosphine and triethylamine provides a sufficient route for the synthesis of dialkyl N-(arylsulfonyl)-4-ethoxy-5-oxo-2,5-dihydro -1H-pyrolle-2,3-dicarboxylates in good yields. 展开更多
关键词 Arylsulfonamides Dialkyl acetylenedicarboxylates Triphenylphosphine Multi-component reactions 3-Pyrollin-2-ones
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A New S-Box Design System for Data Encryption Using Artificial Bee Colony Algorithm 被引量:1
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作者 Yazeed Yasin Ghadi Mohammed SAlshehri +4 位作者 Sultan Almakdi Oumaima Saidani Nazik Alturki Fawad Masood Muhammad Shahbaz Khan 《Computers, Materials & Continua》 SCIE EI 2023年第10期781-797,共17页
Securing digital image data is a key concern in today’s information-driven society.Effective encryption techniques are required to protect sensitive image data,with the Substitution-box(S-box)often playing a pivotal ... Securing digital image data is a key concern in today’s information-driven society.Effective encryption techniques are required to protect sensitive image data,with the Substitution-box(S-box)often playing a pivotal role in many symmetric encryption systems.This study introduces an innovative approach to creating S-boxes for encryption algorithms.The proposed S-boxes are tested for validity and non-linearity by incorporating them into an image encryption scheme.The nonlinearity measure of the proposed S-boxes is 112.These qualities significantly enhance its resistance to common cryptographic attacks,ensuring high image data security.Furthermore,to assess the robustness of the S-boxes,an encryption system has also been proposed and the proposed S-boxes have been integrated into the designed encryption system.To validate the effectiveness of the proposed encryption system,a comprehensive security analysis including brute force attack and histogram analysis has been performed.In addition,to determine the level of security during the transmission and storage of digital content,the encryption system’s Number of Pixel Change Rate(NPCR),and Unified Averaged Changed Intensity(UACI)are calculated.The results indicate a 99.71%NPCR and 33.51%UACI.These results demonstrate that the proposed S-boxes offer a significant level of security for digital content throughout its transmission and storage. 展开更多
关键词 S-BOX CHAOS artificial bee colony image encryption
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A Matlab/Simulink-Based Photovoltaic Array Model Employing SimPowerSystems Toolbox 被引量:1
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作者 Samer Said Ahmed Massoud +1 位作者 Mohieddine Benammar Shehab Ahmed 《Journal of Energy and Power Engineering》 2012年第12期1965-1975,共11页
The modeling of PV (photovoltaic) systems is very crucial for embedded power system applications and maximum power point tracking. This paper presents a PV array model using Matlab/Simulink with the assistance of Si... The modeling of PV (photovoltaic) systems is very crucial for embedded power system applications and maximum power point tracking. This paper presents a PV array model using Matlab/Simulink with the assistance of SimPowerSystem toolbox. The PV cell is considered as the main building block for simulating and monitoring the PV array performance. The PV model has been developed and used as Simulink subsystems where the effect of solar insolation and PV array temperature on commercial PV modules have been studied throughout the simulated I-V and P-V output characteristics. The proposed model facilitates simulating the dynamic performance of PV-based power systems. The effect of different partial shading patterns of PV arrays under different configurations has been studied. 展开更多
关键词 Modeling PV solar energy MATLAB shading.
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Thermally decarboxylated sodium bicarbonate:Interactions with water vapour,calorimetric study
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作者 Natalia Volkova Henri Hansson Lennart Ljunggren 《Journal of Pharmaceutical Analysis》 SCIE CAS 2013年第3期193-199,共7页
Isothermal titration calorimetry (ITC) was used to study interactions between water vapour and the surface of thermally converted sodium bicarbonate (NaHCO3). The decarboxyla- tion degree of the samples was varied... Isothermal titration calorimetry (ITC) was used to study interactions between water vapour and the surface of thermally converted sodium bicarbonate (NaHCO3). The decarboxyla- tion degree of the samples was varied from 3% to 35% and the humidity range was 54-100%. The obtained enthalpy values were all exothermic and showed a positive linear correlation with decarboxylation degrees for each humidity studied. The critical humidity, 75% (RHo), was determined as the inflection point on a plot of the mean-AH kJ/mole Na2CO3 against RH. Humidities above the critical humidity lead to complete surface dissolution. The water uptake (m) was determined after each calorimetric experiment, complementing the enthalpy data. A mechanism of water vapour interaction with decarboxylated samples, including the formation of trona and Wegscheider's salt on the bicarbonate surface is proposed for humidities below RHo. 展开更多
关键词 Isothermal titrationcalorimetry Sodium bicarbonate Sodium carbonate Trona salt Wegscheider's salt ENTHALPY Relative humidity Pyrolyticdecarboxylation
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Synthesis and Crystal Structure of Methyl 2-(Diphenylamino)-4-phenyl-1,3-thiazole-5-carboxylate
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作者 Ali Souldozi Seyed Hamid Reza Shojaei +2 位作者 Ali Ramazani Katarzyna lepokura Tadeusz Lis 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第1期82-88,共7页
The title compound, methyl 2-(diphenylamino)-4-phenyl-1,3-thiazole-5-carboxylate, was synthesized and studied by single-crystal X-ray diffraction method. The structure of the product was confirmed by IR, 1H- and 13C... The title compound, methyl 2-(diphenylamino)-4-phenyl-1,3-thiazole-5-carboxylate, was synthesized and studied by single-crystal X-ray diffraction method. The structure of the product was confirmed by IR, 1H- and 13C-NMR spectroscopy and elemental analysis. These experimental studies were supported by quantum mechanical calculations. The structure was solved in monoclinic, space group P21/c with a = 9.573(3), b = 19.533(7), c = 9.876(3), β = 92.35(4)°, V = 1845.2(10)3, T = 85(2) K, Z = 4, R = 0.040 and wR = 0.089 for 6424 observed reflections with I2σ(I). 展开更多
关键词 single-crystal X-ray structure multi-component reaction methyl 2-(diphenylamino)-4-phenyl-1 3-thiazole-5-carboxylate benzoyl isothiocyanate DIPHENYLAMINE dimethyl acetylenedicarboxylate
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A Mathematical Approach for Generating a Highly Non-Linear Substitution Box Using Quadratic Fractional Transformation
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作者 Abid Mahboob Muhammad Asif +3 位作者 Rana Muhammad Zulqarnain Imran Saddique Hijaz Ahmad Sameh Askar 《Computers, Materials & Continua》 SCIE EI 2023年第11期2565-2578,共14页
Nowadays,one of the most important difficulties is the protection and privacy of confidential data.To address these problems,numerous organizations rely on the use of cryptographic techniques to secure data from illeg... Nowadays,one of the most important difficulties is the protection and privacy of confidential data.To address these problems,numerous organizations rely on the use of cryptographic techniques to secure data from illegal activities and assaults.Modern cryptographic ciphers use the non-linear component of block cipher to ensure the robust encryption process and lawful decoding of plain data during the decryption phase.For the designing of a secure substitution box(S-box),non-linearity(NL)which is an algebraic property of the S-box has great importance.Consequently,the main focus of cryptographers is to achieve the S-box with a high value of non-linearity.In this suggested study,an algebraic approach for the construction of 16×16 S-boxes is provided which is based on the fractional transformation Q(z)=1/α(z)^(m)+β(mod257)and finite field.This technique is only applicable for the even number exponent in the range(2-254)that are not multiples of 4.Firstly,we choose a quadratic fractional transformation,swap each missing element with repeating elements,and acquire the initial S-box.In the second stage,a special permutation of the symmetric group S256 is utilized to construct the final S-box,which has a higher NL score of 112.75 than the Advanced Encryption Standard(AES)S-box and a lower linear probability score of 0.1328.In addition,a tabular and graphical comparison of various algebraic features of the created S-box with many other S-boxes from the literature is provided which verifies that the created S-box has the ability and is good enough to withstand linear and differential attacks.From different analyses,it is ensured that the proposed S-boxes are better than as compared to the existing S-boxes.Further these S-boxes can be utilized in the security of the image data and the text data. 展开更多
关键词 Block cipher S-BOX data security fractional transformation
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Dynamic S-Box Generation Using Novel Chaotic Map with Nonlinearity Tweaking
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作者 Amjad Hussain Zahid Muhammad Junaid Arshad +2 位作者 Musheer Ahmad Naglaa F.Soliman Walid El-Shafai 《Computers, Materials & Continua》 SCIE EI 2023年第5期3011-3026,共16页
A substitution box(S-Box)is a crucial component of contemporary cryptosystems that provide data protection in block ciphers.At the moment,chaotic maps are being created and extensively used to generate these SBoxes as... A substitution box(S-Box)is a crucial component of contemporary cryptosystems that provide data protection in block ciphers.At the moment,chaotic maps are being created and extensively used to generate these SBoxes as a chaotic map assists in providing disorder and resistance to combat cryptanalytical attempts.In this paper,the construction of a dynamic S-Box using a cipher key is proposed using a novel chaotic map and an innovative tweaking approach.The projected chaotic map and the proposed tweak approach are presented for the first time and the use of parameters in their workingmakes both of these dynamic in nature.The tweak approach employs cubic polynomials while permuting the values of an initial S-Box to enhance its cryptographic fort.Values of the parameters are provided using the cipher key and a small variation in values of these parameters results in a completely different unique S-Box.Comparative analysis and exploration confirmed that the projected chaoticmap exhibits a significant amount of chaotic complexity.The security assessment in terms of bijectivity,nonlinearity,bits independence,strict avalanche,linear approximation probability,and differential probability criteria are utilized to critically investigate the effectiveness of the proposed S-Box against several assaults.The proposed S-Box’s cryptographic performance is comparable to those of recently projected S-Boxes for its adaption in real-world security applications.The comparative scrutiny pacifies the genuine potential of the proposed S-Box in terms of its applicability for data security. 展开更多
关键词 Substitution-box chaotic map data security tweaking
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Developing a Prototype Piezoelectric Wafer-Box for Optimal Energy Harvesting
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作者 Ahmad S. Seonghoon Kim +2 位作者 Mohammad A. Junan S. Yong B. 《Journal of Civil Engineering and Architecture》 2022年第1期1-12,共12页
Piezoelectric(PZ)energy has been paid attention to as conventional renewable energy sources including solar,wind,and geothermal power.To address the dilemma of climatic conditions affecting the energy harvesting using... Piezoelectric(PZ)energy has been paid attention to as conventional renewable energy sources including solar,wind,and geothermal power.To address the dilemma of climatic conditions affecting the energy harvesting using Lead Zirconate Titanate(PZT)in pavement,wafer-boxes were used with embedded PZT sensors,since wafer-boxes have the ability to be embedded in the pavement where sensors are protected from any kind of physical damage.This research project was designed to identify which shaped wafer-box produced the most electric voltage and power.Various forms of wafer-box were developed to identify if there was any potential difference in voltage generation due to the structural shapes of the box.Seven different shapes of prototype wafer-boxes were designed utilizing both a 3D printer and 3D Computer Aided Design(CAD).These wafer-boxes were coupled with embedded PZT sensors which were tested in asphalt pavement analyzer(APA)machine under certain load to produce electric voltage.Collected voltage data from the APA wheel load test(WLT)were analyzed using various statistical methods.The statistical analyses results indicated that out of the seven different shaped wafer-boxes,the right-angled triangular shaped box produced the highest average voltage values where’s square shaped wafer-box produced the lowest amount of voltage.Structural properties of a wafer-box in terms of section modulus,area moment of inertia,extreme points,and radius of gyration were also analyzed,and a regression analysis was conducted to identify the reasons of different amounts of voltage produced.These voltage values could be used to calculate the power using power formulas showing relationship between power and voltage values.The outcome helped to identify which shape is most effective to power generation under certain circumstances.The regression analysis results indicated that out of four properties the section modulus is the most influential structural property affecting voltage production. 展开更多
关键词 PIEZOELECTRICITY PZT materials voltage wafer-box experiment design section MODULUS
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DABCO-catalyzed multi-component domino reactions for green and efficient synthesis of novel 3-oxo-3H-benzo[a]pyrano[2,3-c]phenazine-1-carboxylate and 3-(5-hydroxybenzo[a]phenazin-6-yl)acrylate derivatives in water
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作者 Razieh Mohebat Afshin Yazdani-Elah-Abadi +1 位作者 Malek-Taher Maghsoodlou Nourallah Hazeri 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第5期943-948,共6页
An efficient,convenient and environmentally benign procedure for the synthesis of novel 3-oxo-3Hbenzo[a]pyrano[2.3-c]phenazine-l-carboxylate and 3-(5-hydroxybenzo[a]phenazin-6-yl) acrylate derivatives has been devel... An efficient,convenient and environmentally benign procedure for the synthesis of novel 3-oxo-3Hbenzo[a]pyrano[2.3-c]phenazine-l-carboxylate and 3-(5-hydroxybenzo[a]phenazin-6-yl) acrylate derivatives has been developed by domino three-component condensation reaction between 2-hydroxynaphthalene-1,4-dione,benzene-1,2-diamines and acetylenic esters in the presence of a catalytic amount of DABCO as an expedient,eco-friendly and reusable base catalyst in water.This green process produces biologically and pharmacologically significant heterocycles in a one-pot single operation and offers considerable advantages such as:operational simplicity,short reaction time,high yields,reusability of catalyst,absence of any tedious workup or purification and avoids hazardous reagents/solvents. 展开更多
关键词 Multi-component domino reactions(MDRs) DABCO Acetylenic esters Benzo[a]phenazin derivatives Green chemistry
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Exploring Nanoscale Perovskite Materials for Next‑Generation Photodetectors:A Comprehensive Review and Future Directions 被引量:2
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作者 Xin Li Sikandar Aftab +4 位作者 Maria Mukhtar Fahmid Kabir Muhammad Farooq Khan Hosameldin Helmy Hegazy Erdi Akman 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期46-108,共63页
The rapid advancement of nanotechnology has sparked much interest in applying nanoscale perovskite materials for photodetection applications.These materials are promising candidates for next-generation photodetectors(... The rapid advancement of nanotechnology has sparked much interest in applying nanoscale perovskite materials for photodetection applications.These materials are promising candidates for next-generation photodetectors(PDs)due to their unique optoelectronic properties and flexible synthesis routes.This review explores the approaches used in the development and use of optoelectronic devices made of different nanoscale perovskite architectures,including quantum dots,nanosheets,nanorods,nanowires,and nanocrystals.Through a thorough analysis of recent literature,the review also addresses common issues like the mechanisms underlying the degradation of perovskite PDs and offers perspectives on potential solutions to improve stability and scalability that impede widespread implementation.In addition,it highlights that photodetection encompasses the detection of light fields in dimensions other than light intensity and suggests potential avenues for future research to overcome these obstacles and fully realize the potential of nanoscale perovskite materials in state-of-the-art photodetection systems.This review provides a comprehensive overview of nanoscale perovskite PDs and guides future research efforts towards improved performance and wider applicability,making it a valuable resource for researchers. 展开更多
关键词 Nanoscale perovskites PHOTODETECTORS NANOSHEETS NANORODS NANOWIRES Quantum dots NANOCRYSTALS
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