Journal of Chemistry: Education Research and Practice最新文献

{"title":"New Approaches to Simulation of Enzymatic Reactions: Mimetic Catalysis","authors":"","doi":"10.33140/jcerp.03.02.01","DOIUrl":"https://doi.org/10.33140/jcerp.03.02.01","url":null,"abstract":"The examples given below, for instance, methane oxidation to methanol and propylene oxidation to propylene\u0000oxide, demonstrate experimental approaches to the study of interfering reaction dynamics and, with the help of the\u0000determinant equation, the potential abilities of reaction media are assessed and the type of chemical interference\u0000determined.","PeriodicalId":262953,"journal":{"name":"Journal of Chemistry: Education Research and Practice","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128847950","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":"Levels of Benzoic and Sorbic Acid Preservatives in Commercially Produced Ready to\u0000Serve Products in Sri Lanka","authors":"","doi":"10.33140/jcerp.03.02.02","DOIUrl":"https://doi.org/10.33140/jcerp.03.02.02","url":null,"abstract":"Benzoic acid, sorbic acid are widely used for food preservation. The analyses of these preservatives in 100 different\u0000food products were performed. Therefore 100 samples including, 10 carbonated beverages, 20 jams, 10 jelly drinks,\u000010 jelly cups, 30 ready to serve drinks, 10 nectars, and 10 sauces were analysed by using high performance liquid\u0000chromatography. The HPLC determination of the preservatives was performed using a reversed – phase C18\u0000column and UV detection at 235 nm. Flow rate approximately 1.2ml/min. Eluent for HPLC, mix 50 volume parts of\u0000Ammonium Acetate solution with 40 volume parts of methanol for HPLC and adjust to a pH of 4.5 to 4.6 with acetic\u0000acid. The preservative concentration in samples was used as external standards for sodium benzoate and potassium\u0000benzoate. Levels were compared with Food Act and Food Standards Regulation in Sri Lanka. Both benzoic acid\u0000and sorbic acid were detected in a range of 1120ppm to 30ppm and 582ppm to 16ppm respectively. Although 65%\u0000of the samples was not compliant with the Food Act and Food Regulations in Sri Lanka.","PeriodicalId":262953,"journal":{"name":"Journal of Chemistry: Education Research and Practice","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125101947","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":"Synthesis and Structural Studies on some Dioxomolybdenum (VI) Complexes Bearing\u00001-(1-Hydroxynaphthalen-2-yl) Ethanone Moiety","authors":"M. M. Shanab, M. S. El-Shahawib, Mohsen M Mostafac","doi":"10.33140/jcerp.03.01.03","DOIUrl":"https://doi.org/10.33140/jcerp.03.01.03","url":null,"abstract":"A number of new molybdenum complexes Cis-MoO2\u0000(NE)2\u0000.CH3\u0000OH, Cis-MoO2\u0000(HRSB)2\u0000.nH2\u0000O {R= H, 4-Br, 4-OCH3\u0000, 4-CH3\u0000 and\u0000n= 0, 1, 2} Cis-MoO2\u0000(HL)(acac).nH2\u0000O {HL= HNEBH, HNEINH, HNENH, HNEPH, n=0, 1}, Cis-[MoO2\u0000(L)2\u0000.nH2\u0000O], {L=\u0000HNE-2-ABH, HNE-4-ABH, n = 0, 2} and Cis-[Mo2\u0000O5\u0000(HNEAH)2\u0000] have been synthesized and characterization by magnetic,\u0000spectroscopic (FT-IR, 1H and 13C-NMR spectra) and electrochemical techniques. The complexes were made reaction of\u0000Cis-MoO2\u0000(acac)2\u0000 with the ligands, (1-hydroxynaphthalen-2-yl)ethenone (HNE), (E)-2-(1-(phenylimino)ethyl)naphthalen1-ol (HASB), (E)-2-(1-(p-tolylimino)ethyl) naphthalen-1-ol (HTSB), E-2-(1-(4-methoxyphenylimino)ethyl)naphthalen-1-ol\u0000(HMSB) and (E)-2-(1-(4-bromophenylimino)ethyl)naphthalen-1-ol (HBrSB) monobasic bidentate (NO) or 2-anmino-N/-\u0000(1-(1-hydroxynaphthalene-2-yl)ethylidene)benzohydrazide (HNE2-ABH), 4-anmino-N/-(1-(1-hydroxynaphthalene-2-yl)\u0000ethylidene)benzohydrazide (HNE4-ABH), N/-(1-(1-hydroxynaphthalene-2-yl)ethylidene)benzohydrazide (HNEBH),\u0000N-(1-(1-hydroxynaphthalene-2-yl)ethylidene)acetohydrazide (HNEAH), N/-(1-(1-hydroxynaphthalene-2-yl)ethylidene)\u0000nicotinohydrazide (HNENH), N/-(1-(1-hydroxynaphthalene-2-yl)ethylidene)isonicotinohydrazide (HNEINH), N/-(1-\u0000(1-hydroxynaphthalene-2-yl)ethylidene)picolinohydrazide (HNEPH), they coordinate as dibasic tridentate (OON).\u0000Both the molecular and the spectroscopic studies showed that, the complexes are octahedrally coordinated. The redox\u0000properties, of the electrode couples and the stability of some complexes towards reduction were linked to the electron\u0000withdrawing or ability releasing of the substituent in the Schiff bases and the hydrazones. Results show that, changes\u0000in E1/2 for the complexes due to remote substituent effects could be related to changes in basicity of the carbonyl oxygen\u0000of the hydrazide moiety in the hydrazone ligand. The electron-donating substituents stabilized Mo(VI) complexes while\u0000electron-withdrawing groups favored lower oxidation state of Mo(V) and/ or Mo(IV) species. The nature of mechanism\u0000and kinetic parameters of the electroactive chelates are strongly dependent on the substituent. The EHOMO and ELUMO\u0000level, of hydrazone and some of Cis-molybdenum complexes, from both electrochemical and theoretical data also backdonation energy (ΔEback-donation), ionization potential (I), molecular dipole moment (μ), electronegativity (χ), softness (σ)\u0000electron affinity (A), global hardness (η), and electrophilicity index (ω) were calculated.","PeriodicalId":262953,"journal":{"name":"Journal of Chemistry: Education Research and Practice","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115497820","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":"Nature of Chemical Elements","authors":"Filipenka Henadzi","doi":"10.33140/jcerp.03.01.02","DOIUrl":"https://doi.org/10.33140/jcerp.03.01.02","url":null,"abstract":"The main problem is that using X-rays, we have determined the crystal lattices of different materials, and why they\u0000are so, and not others are not yet known. For example, copper crystallizes in the fcc lattice, and iron in the bcc,\u0000which becomes fcc on heating, this is used for heat treatment of steels. Copper does not change the crystal lattice\u0000when heated. There are many factors affecting the crystallization in the literature, so they decided to remove them as\u0000much as possible, and the metal model in the article, say so, is ideal, i.e. all atoms are the same (pure metal) without\u0000inclusions, without implants, without defects, etc. using the Hall effect and other data on properties, as well as the\u0000calculations of Ashcroft and Mermin, my main determining factor for the type of lattice was the core of the atom\u0000or ion, which resulted from the transfer of some electrons to the conduction band. It turned out that the metal bond\u0000is due not only to the socialization of electrons, but also to external electrons of atomic cores, which determine the\u0000direction or type of the crystal lattice. The change in the type of metal lattice can be connected with the transition\u0000of an electron to the conduction band or its return from this zone. Phase transition. It is shown that in the general\u0000case, the metal bond in the closest packages (hec and fcc) between the centrally chosen atom and its neighbors is\u0000presumably carried out by means of nine (9) directional bonds, in contrast to the number of neighbors equal to 12\u0000(twelve) (coordination number). Probably the “alien” 3 (three) atoms are present in the coordination number 12\u0000stereometrically, and not because of the connection. The answer is to give an experimental test.","PeriodicalId":262953,"journal":{"name":"Journal of Chemistry: Education Research and Practice","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123833824","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":"An overview of the first year Undergraduate Medical Students Feedback on the Point\u0000of Care Ultrasound Curriculum","authors":"","doi":"10.33140/jcerp/02/01/12","DOIUrl":"https://doi.org/10.33140/jcerp/02/01/12","url":null,"abstract":"With the technological progress of different types of portable Ultrasound machines, there is a growing demand by\u0000all health care providers to perform bedside Ultrasonography, also known as Point of Care Ultrasound (POCUS).\u0000This technique is becoming extremely useful as part of the Clinical Skills/Anatomy teaching in the undergraduate\u0000Medical School Curriculum.\u0000Teaching/training health care providers how to use these portable Ultrasound machines can complement their\u0000physical examination findings and help in a more accurate diagnosis, which leads to a faster and better improvement\u0000in patient outcomes. In addition, using portable Ultrasound machines can add more safety measurements to every\u0000therapeutic/diagnostic procedure when it is done under an Ultrasound guide. It is also considered as an extra tool\u0000in teaching Clinical Anatomy to Medical students. Using an Ultrasound is one of the different imaging modalities\u0000that health care providers depend on to reach their diagnosis, while also being the least invasive method.\u0000We thought investing in training the undergraduate Medical students on the basic Ultrasound scanning skills as part\u0000of their first year curriculum will help build up the foundation for their future career","PeriodicalId":262953,"journal":{"name":"Journal of Chemistry: Education Research and Practice","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114728470","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":"Regio-Selective Reaction, Spectroscopic Characterization and Computational Chemical Study of (Hesperidin) Hesperetin-7-O-Rutinoside Analogs as Antimicrobial Agents","authors":"","doi":"10.33140/jcerp.02.01.13","DOIUrl":"https://doi.org/10.33140/jcerp.02.01.13","url":null,"abstract":"Flavonoids display a strong antioxidant and radical scavenging activity and seem to beassociated with reduced danger for certain chronic diseases, the prevention of some cardiovascular sicknesses and certain types of cancerous processes [1-4]. Flavonoids show also antiviral, antimicrobial, and anti-inflammatory activities, helpful on capillary fragility and prevent human platelet aggregation, antiulcer and antiallergenic [5-11]. Though, the actual in vivo mechanism of action is largely unknown. Most studies have attentivein vitro tests at amounts much higher than in humans,however few clinical investigations have been carried out around the diseases [12].Additional clinical trials are required to evaluate a more precise correlation between flavonoids consumption and human health benefits [13]. The possible mechanism of potential experimentalactionhas been studied [14]. Citrus juices attitude among the most significant phenolicrich dietary sources [15].","PeriodicalId":262953,"journal":{"name":"Journal of Chemistry: Education Research and Practice","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128184339","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}