Revista de Chimie最新文献

{"title":"Optimisation of Zinc Oxide Nanoparticle Biosynthesis Using Saccharomyces Cerevisiae with Box-Behnken Design","authors":"Fitry Mulyani, M. Permana, S. Ishmayana, I. Rahayu, D. Eddy","doi":"10.37358/RC.21.1.8405","DOIUrl":"https://doi.org/10.37358/RC.21.1.8405","url":null,"abstract":"Zinc oxide nanoparticles have wide applications as catalysts, antimicrobial agents, drug delivery agents, etc. because of their intrinsic properties. Various methods can be applied to synthesise nanoparticles, one of which is the biosynthesis process. Biosynthesis is more eco-friendly than chemical and physical methods. In the present study, the optimisation of zinc oxide nanoparticle biosynthesis using the yeast Saccharomyces cerevisiae was performed by applying a response surface method called the Box–Behnken design (BBD). Three factors were optimised in the present study, namely the concentration of zinc acetate as the precursor (X1), concentration of the S. cerevisiae fermentation broth (X2), and the incubation time (X3). The mass of zinc oxide nanoparticles (Y) was recorded as the response of the experiment. The product was then characterised by fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD), scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS), and particle size analyser (PSA). The optimum conditions for the preparation of zinc oxide nanoparticles were found to be 0.3 M, 100% (v/v), and 24 h as the zinc acetate concentration, medium concentration, and incubation time, respectively. The FTIR analysis showed peaks at ~600 cm, which is characteristic for ZnO stretching. From the XRD result, the ZnO nanoparticles with hexagonal structure was confirm. The SEM/EDS analysis confirmed that the morphology was spherical and showed the major energy emission for zinc and oxygen. Moreover, the PSA analysis revealed that the smallest size was 218.6 nm (12%) when the synthesis was performed at the optimum conditions, while when the incubation time was prolonged for 120 h, the size decreased to 134.2 nm.","PeriodicalId":21296,"journal":{"name":"Revista de Chimie","volume":"19 1","pages":"79-89"},"PeriodicalIF":0.0,"publicationDate":"2021-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88626618","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Increasing Corrosion Resistance of Pressure Vessels at the Hydrostatic Pressure Testing by Using Inhibitors","authors":"M. Iordoc, Georgiana Marin, Georgeta Stoianovici, P. Prioteasa, Cristinel Bălan, M. Guta, Radu Furtuna","doi":"10.37358/RC.21.1.8399","DOIUrl":"https://doi.org/10.37358/RC.21.1.8399","url":null,"abstract":"Studies of the corrosion initiation at the pressure hydraulic test of pressure vessels during their filling, maintaining and draining are presented. It has been established that the most suitable method involves the use of corrosion inhibitors, which directly decrease the corrosion rate even in small or very small quantities. It was studied the influence of some corrosion inhibitors at different concentrations on some steel materials commonly used at pressure vessels manufacturing. The study involved the inhibitors testing both in laboratory and in factory conditions. Testing in laboratory conditions involved the analysis of the following inhibitors: urea, thiourea, triethanolamine, FINEAMIN 88 and FINEAMIN 06. The results were compared with those of the Adirol inhibitor, the currently used inhibitor. It was investigated the corrosion of the following stainless steels and unalloyed steels: A 240 grade 304, A 240 grade 316, A 516 grade 70, A 516 grade 60, P260-GH, P265, P275, P295-GH, P295, and P355. By recording the potentiodynamic polarization curves, the corrosion parameters (corrosion potential, corrosion current density, polarization resistance, corrosion rate, charge transfer coefficients for anodic and cathodic processes, inhibitors acting coefficients, and inhibition efficiencies) have been evaluated. The following corrosion inhibitor solutions were selected for testing under the factory specific conditions: Instal Protect SP at concentrations of 5%, 7.5% and 10%, ELG INCOR SP at 10% concentration, FINEAMIN 06 at 10/00 concentration and a mixture of 40mL FINEAMIN 06 + 40 mL FINEAMIN 88 SCAV25 in 40 L water. The analysed steels were A 106 grade B and A 283 grade C. Tests in laboratory conditions revealed a different behaviour of the inhibitors, depending on the analysed concentration and steel grade. The inhibitors proven as appropriate following the tests in the factory conditions were ELG INCOR SP used in industrial water (tap water), whereas the mixture of FINEAMIN 06 + FINEAMIN 88 SCAV25 had efficiency only in demineralised water.","PeriodicalId":21296,"journal":{"name":"Revista de Chimie","volume":"3 1","pages":"1-17"},"PeriodicalIF":0.0,"publicationDate":"2021-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88787756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermodynamic and Kinetic Study on the Catalysis of Isobornyl Acetate by a Cation Exchange Resin an Intensified Fixed-Bed Reactor","authors":"W. Dong, L. Chen, Hanzhao Yan, Zi-ping Zhang, Zheng Zhou","doi":"10.37358/RC.21.1.8408","DOIUrl":"https://doi.org/10.37358/RC.21.1.8408","url":null,"abstract":"Esterification Thermodynamic and Kinetic on acetic acid with camphene was studied systematically in an intensified fixed bed reactor at 303-323 K with anhydrous NKC-9 resin. The catalyst loading, initial molar ratio, temperature, and catalyst reusability were studied and optimized. The method of UNIFAC was applied to calculate the activity coefficient of each component for correcting the nonideality of the solution. Reaction enthalpy, entropy, and Gibbs free energy were calculated. The kinetics of camphene esterification was studied by pseudo-homogeneous model (PH model), and the fitting effect was good, which provided experimental reference and theoretical basis for the industrial production of isobornyl acetate.","PeriodicalId":21296,"journal":{"name":"Revista de Chimie","volume":"35 1","pages":"111-124"},"PeriodicalIF":0.0,"publicationDate":"2021-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81096333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Considerable Improvement in Fenton-like Degradation of MB Owing to Ti3+/Ti4+ Using Ion-doped Halloysite Nanotube Catalyst","authors":"Yuan Wei, Yating Sun, Dahua Li, B. Lu, Miaohua Liu, Gonggang Liu, Jinbo Hu","doi":"10.37358/RC.21.1.8404","DOIUrl":"https://doi.org/10.37358/RC.21.1.8404","url":null,"abstract":"Due to high efficiency and environmental friendship, Fenton-like technology is widely used in water treatment and has always received significant attentions, especially in design of novel and efficient Fenton-like catalysts. In this paper, iron/titanium ions doped halloysite nanotubes (HNTs-Fe-Ti) have been developed as Fenton-like catalyst. Here, halloysite nanotubes (HNTs) with high specific surface area and excellent ion exchange capacity were used as carriers, and iron/titanium ions were tracedoped into HNTs via simple ion-exchange reaction. The degradation of the designed catalyst for methylene blue (MB) was greatly accelerated in the presence of titanium ion. It demonstrates that the excellent degradation ability mainly owes to the valence state transformation of titanium and the good adsorption ability of halloysite nanotubes. It shows the mechanism of titanium with multivalent states (Ti/Ti) on the degradation of MB is similar to the Fenton catalytic mechanism of iron ion transformation (Fe/Fe). In the Fenton-like degradation reaction, titanium and iron play a synergistic catalytic role in MB degradation while titanium has greater impact. When the ratio of titanium to iron is 5:1, the catalyst exhibits superior Fenton-like degradation performance, and the degradation rate could reach 91% at 100 min.","PeriodicalId":21296,"journal":{"name":"Revista de Chimie","volume":"60 1","pages":"66-78"},"PeriodicalIF":0.0,"publicationDate":"2021-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74082642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study the Effect of Gum Arabic and Triton X-100 on Stability and Thermal Conductivity of ZnO/ethylene glycol Nanofluids","authors":"Noor Sabeeh Majeed, H. A. Alabdly, Hussam Nadum Abdalraheem Al Ani, Dumitru Pașcu, A. Nechifor","doi":"10.37358/RC.21.1.8400","DOIUrl":"https://doi.org/10.37358/RC.21.1.8400","url":null,"abstract":"Stability of nanofluids is one of the most important factors to ensure the most benefit of the properties of nanoparticles. Zinc oxide was used in the research with concentration between (0.2-1) wt. % with ethylene glycol base fluid. The stability of ZnO nanofluid was enhanced by adding two types of surfactants Tx-100 and Gum Arabic with concentration of (0.1-0.5) vol. % to stabilize the ZnO nanoparticles in the base fluid. The results showed that the Gum Arabic surfactant led to more stable fluid than that of Tx-100; this was shown from zeta potential and UV spectroscopy measurements. The thermal conductivity coefficient was also measured, and the results showed that the thermal conductivity increased with adding surfactant than without using a stabilizer.","PeriodicalId":21296,"journal":{"name":"Revista de Chimie","volume":"96 1","pages":"18-24"},"PeriodicalIF":0.0,"publicationDate":"2021-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85276868","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Removal of Toxic Phenolic Compounds from Wastewater Using Zeolite (4A) Prepared from Local Clays Taken from the Slopes of the Tigris River","authors":"H. A. Alabdly, Inas J. Al-Nuaemi, Hussam Nadum Abdalraheem Al Ani, Simona Cotorcea, A. Nechifor","doi":"10.37358/RC.21.1.8402","DOIUrl":"https://doi.org/10.37358/RC.21.1.8402","url":null,"abstract":"The massive scale of industrial development has resulted in environmental pollution in general and water contamination in particular. It is important at the present time to treat water for the purpose of eliminating or reducing pollutants, especially toxic pollutants, such as phenol compounds. In this study, zeolite (4A) was prepared firstly from the available and cheap materials using an inclined rotary disk. Then, physical, mechanical, and chemical properties were also studied. Experiments were conducted to determine these properties using local clay and the following results were obtained: Zeolite (4A) 70% and clay 30%, the time of calcination 3 h at a temperature of 850 ̊C, breakage resistance of 17 Ib pounds, surface area 530-590 m/g, grinding value 14% and moisture absorption ratio 30%. The prepared zeolite (4A) was used in the process of removing phenolic compounds (chlorophenol, nitrophenol) by the adsorption method. Different amounts of prepared zeolite (5g/l and 10g/L) will be used in the treatment process and different concentrations (2mg/L, 5 mg/L and 10 mg/L) of the pollutants Nitrophenol and Chlorophenol were used in the contaminated water tested. The removal process was carried out with a mixing speed of 200 rpm and pH (7.5-8.5). From the results of this study, we note that the highest percentage of Nitrophenol removal is (84.8%) when using an amount of zeolite (5g) and highest percentage of Nitrophenol removal is (95.5%) when using an amount of zeolite (10g) while that the highest percentage of Chlorophenol removal is (78.3%) when using an amount of zeolite (5g) and highest percentage of Chlorophenol removal is (0.894) when using an amount of zeolite (10g) it could be deduced that the percentage of the removal of nitrophenol was higher than that of chlorophenol because its solubility of chlorophenol in water is higher than the solubility of Nitrophenol.","PeriodicalId":21296,"journal":{"name":"Revista de Chimie","volume":"1 1","pages":"44-52"},"PeriodicalIF":0.0,"publicationDate":"2021-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80549504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chemical Safety Management Training Hub for Downstream Users & Distributers of Chemicals","authors":"T. Hărătău, I. Precup, S. Ştefănescu","doi":"10.37358/RC.21.1.8409","DOIUrl":"https://doi.org/10.37358/RC.21.1.8409","url":null,"abstract":"Chemical Safety Management Training Hub for Chemicals Users/ChemSM-HUB – project funded under Erasmus+ Programme has been tailored to meet the training needs related to legal provisions under REACH & CLP Regulations of employees responsible for CSM among downstream users (DU) and distributers (D) of chemicals. The strategic objectives proposed by the project were to increase awareness of relevant professional communities on the new European legislation on CSM, strengthen the competencies of the target groups in the field of CSM, and enhance the ability of trainers to create and deliver vocational training. The design and concept of the training hub and the training materials have been established based on a training needs assessment, which also provided the necessary information to define the training objectives, the format, and the type of materials to be developed. To ensure high quality of the training, but also the availability in a user-friendly format, the training materials and the training hub have been developed and improved progressively as part of a consortium peer-review process during the joint-staff training organized in Romania according to the format of Erasmus+ Programme KA202 Strategic Partnerships for vocational education and training. Also, the materials created have been subjected to pilot testing during the blended mobility training of VET learners within Erasmus+ Programme which, according to the new circumstances imposed by Sars-Cov-2 pandemic has been organized strictly online using an integrated approach of a webinar application and the ChemSM-HUB e-learning platform. According to the feedback received in both cases – during peer review and the pilot training materials and the hub have been subject to various changes and resulted in a comprehensive training package and, respectively, a training hub that facilitates individual study and certification of the DU & D of chemicals, and provides access to up-todate information in a concise and structured format.","PeriodicalId":21296,"journal":{"name":"Revista de Chimie","volume":"4 1","pages":"125-132"},"PeriodicalIF":0.0,"publicationDate":"2021-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90974652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phytochemical Profiling of Medicinal Plants Extracts and Their Antioxidant and Anticancer Potentialities Against Human Liver Cancer (Hep G2) Cell Lines","authors":"N. Shafiq, F. Yasmin, S. Noreen, A. Shahzad, Z. Nazli, S. Parveen, Basharat Ali, Z. Ahmad, M. Rashid, M. Bilal","doi":"10.37358/RC.21.1.8407","DOIUrl":"https://doi.org/10.37358/RC.21.1.8407","url":null,"abstract":"Although Pakistan is stacked with enormous varieties of medicinal plants, only a little proportion of these plants has been evaluated for their medicinal and therapeutic properties. Herein, four indigenous medicinal plants Citrus sinenesis, Citrus paradiasii, Moringa olifera, and Hibiscus rosa-sinenesis were collected and subjected to phytochemical analyses to scrutinize the presence of secondary metabolites. Qualitative analysis showed the presence of an array of secondary metabolites in the selected plants, which were further corroborated by high-performance liquid chromatography. Results revealed the presence of 33.24, 21.04, 15.2 ppm gallic acid in methanol, ethyl acetate and nhexane fraction of C. sinensis peels extract, respectively. C. paradaissi peels consist of 24.06, and 18.24 ppm of gallic acid and caffeic acid, respectively, in methanol and chloroform fractions, whereas its methanolic seeds extract contain caffeic acid as a major component (10.63 ppm). H. rosa-sinenesis has shown p-coumaric acid, caffeic acid, and gallic acid at 35.26, 15.04, and 11.4 ppm, respectively. M. olifera contained 3.24 ppm gallic acid in pods extract while stems and leaves extract contain a very low amount. Anticancer profile evinced that Citrus sinensis extract showed the highest percent inhibition (142.746%) of human liver cancer (Hep G2) cell lines followed by H. rosa-sinensis (132.49%), C. paradaisii (82.39%) and M. olifera (68.0%). The determined IC50 values for antioxidant activity were C. sinenesis (IC50=0.49 mM), C. paradaisii (IC50=0.43 mM), M. olifera (IC50=0.42 mM) and H. rosasinensis (IC50=0.41 mM). Conclusively, the selected plants could be an effective alternative and deliverable chemical therapeutic to the pharmaceutical industry due to their excellent biological effects.","PeriodicalId":21296,"journal":{"name":"Revista de Chimie","volume":"41 1","pages":"100-110"},"PeriodicalIF":0.0,"publicationDate":"2021-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78377008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Xanthan Matrix as Drug ZDelivery System","authors":"N. Anghel, M. V. Dinu, F. Doroftei, I. Spiridon","doi":"10.37358/RC.21.1.8406","DOIUrl":"https://doi.org/10.37358/RC.21.1.8406","url":null,"abstract":"Here we present a new drug delivery system based on xanthan esterified with acrylic acid. This material served as a matrix for the incorporation of bioactive substances with antimicrobial and anti-inflammatory properties. The materials were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR) and Scanning Electron Micrography (SEM). Mechanical strength tests showed a substantial improvement in the resilience and flexibility of the polymer matrix modified by esterification under conditions of mechanical stress. The release of bioactive substances from the basic matrix follows a Korsmeyer-Peppas type kinetics. The modified xanthan-based transport system was shown to be antimicrobial active with an inhibition rate of almost 100% on grampositive and gram-negative bacteria. The obtained results recommend this biomaterial for the manufacture of transdermal drug delivery devices.","PeriodicalId":21296,"journal":{"name":"Revista de Chimie","volume":"30 1 1","pages":"90-99"},"PeriodicalIF":0.0,"publicationDate":"2021-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83575224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preparation and Characterization of Citrus Aurantifolia Lime Oils Microcapsules by Complex Coacervation Technique","authors":"E. Julaeha, M. Nurzaman, D. Eddy, D. Kurnia, S. Puspita, Y. Rosandi, T. Wahyudi, Jamaludin Al Anshori","doi":"10.37358/RC.20.12.8395","DOIUrl":"https://doi.org/10.37358/RC.20.12.8395","url":null,"abstract":"The Lime oil of Citrus aurantifolia was microencapsulated by coacervation technique employing gelatine and alginates as the shells, and calcium chloride as cross linker. Optimization of core/shell ratio, speed and temperature of stirring was carried out. Structure and shape of the microcapsules were characterized by particle size analyzer (PSA) and scanning electron microscope (SEM) respectively. The properties of microcapsules such as, yield, particle size distribution, oil content, oil load, and encapsulation efficiency were also determined. Upon condition of ratio core/shell 0.49, speed and temperature of stirring at 600 rpm and 35 °C respectively, the microcapsules of LOs with improved performance were achieved with efficiency of 46% and oil content of 78%.","PeriodicalId":21296,"journal":{"name":"Revista de Chimie","volume":"50 1","pages":"146-155"},"PeriodicalIF":0.0,"publicationDate":"2021-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80802115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}