Open Access Short Research Article

Study on the Tunable LCST Properties of Phenylalaninate Derivative with Branching Oligoethyleneoxy Chains

Pan Yu, Kundan Hao, Zhou Yang, Liangchun Li

Chemical Science International Journal, Page 1-7
DOI: 10.9734/ACSJ/2016/28842

Thermosensitive amino acid derivative with oligoethyleneoxy chains with tunable lower critical solution temperature (LCST) were prepared from L-methyl phenylalaninate and 3,5-diaminobenzoic acid derivative with oligoethyleneoxy chains. The solution properties and the effects of salt ion species on LCST of phenylalaninate derivative 11 were investigated by UV-vis. The results indicate that the LCST value of 11 could be controlled by adjusting the salt concentration with different cationic species.

Open Access Original Research Article

The Effects of Boric Acid on Fiberboard Made from Wood/Secondary Fiber Mixtures: Part 3. Utilization of Recycled Waste Office Paper Fibers

Ali Ihsan Kaya, Halil Turgut Sahin

Chemical Science International Journal, Page 1-8
DOI: 10.9734/ACSJ/2016/27758

It was discovered that an increase in the proportion of secondary fibers has a negative impact on strength and thickness swelling (TS) properties of experimental boards. However, the highest MOR value of 20.0 MPa was found for type 1 board (C1) produced with a 90/10 Wood/Seconder fiber (W/S) ratio. Likewise, the highest MOE value of 2119 MPa was obtained with the C4 (type1) board. A statistical analysis (ANOVA) clearly indicates that the variables, such as boric acid content and W/S proportions, significantly affect the mechanical properties and that it is indeed possible to produce boards with higher mechanical properties than standard values with an optimum proportion of wood/secondary fiber ratio and a particular boric acid content.

It was found that increasing the secondary fiber proportion at some levels improved sound absorption properties of the boards somewhat. The highest mean value of 0.82 at 2500 Hz was achieved by using the C6 boards, while 0.78 at 2500Hz was obtained for C6a boards, where both types of boards were produced with a ratio (W/S) of 40/60. The lowest thermal conductivity (better insulation) was found to be 0.1729 W/mK in type1 boards that were made with 10/90 (W/S) fiber mixture (C9). It was learnt that boric acid supports heat resistance properties of those experimental boards manufactured from various proportions of W/S mixtures. Indeed, increasing boric acid content has a negative impact on thermal degradation, so that decomposition temperature had to be increased for type 2 boards. FTIR spectra for the two types of boards are not particularly different. Multi-modal absorption in the 1300-1350 cm-1 region was achieved by using boron containing groups.

Open Access Original Research Article

TLC Analysis and GC-MS Profiling of Hexane Extract of Syzygium guineense Leaf

J. I. Abok, C. Manulu

Chemical Science International Journal, Page 1-6
DOI: 10.9734/ACSJ/2016/27372

Syzygium guineense leaf and bark are used for the treatment of tuberculosis, chronic diarrhea, cough, dysentery, malaria, amenorrhea, wounds, ulcers, rheumatism and infections. The various compounds in the n-hexane extract of the leaf were analysed by TLC and identified by GC-MS technique. The TLC results indicated that four (4) terpenes are present in hexane extracts of the leaf of Syzygium guineense after treating TLC plates with vanillin-Conc.H2SO4. The results of the GC-MS analysis revealed twelve (12) compounds in the n-hexane extract of Syzygium guineense leaf. These are 1-ethyl-2-methylbenzene (2.61%), Ylangene (2.42%), decahydro-4a-methyl-1-methylene-7-(1-methylethynyl)-naphthalene(γ-muurolone) (2.47%), 4-dimethyl-7-(1-ethylethenyl)azulene (2.06%), caryophyllene oxide(3.86%), myristic acid (2.11%), n-hexadecenoic acid (11.94%), 9-octadecanoic acid (25.72%), tetratriacontane (31.45%), 1,2-benzenedicarboxylic acid (2.71%), tetratriacontane (6.70%) and pentatriacontane (3.95%). These compounds fall into three classes; terpene/terpenoids, organic acids and hydrocarbons with the major compounds been the organic acids 42.48%. Hydrocarbons constituent 42.1% of the extract while only 0.38% constitute terpenes/terpenoids. The results of this study offer a basis of using S. guineense leaf as an alternative medicinal agent as anti-inflammatory analgesic, antipyretic and platelet-inhibitory actions.

Open Access Original Research Article

Synthesis of Novel Derivatives on the Basis of 4-Hydrazinyl-6-methyl-2-(alkylthio)pyrimidines and Their Preliminary Biological Evaluation

Vergush A. Pivazyan, Emma A. Ghazaryan, Roza S. Shainova, Rafael A. Tavalyan, Armen G. Ayvazyan, Aleksandr P. Yengoyan

Chemical Science International Journal, Page 1-10
DOI: 10.9734/ACSJ/2016/28201

By functionalization of 4-hydrazinyl-6-methyl-2-(alkylthio)pyrimidines the corresponding acetohydrazides, N-phenylhydrazine-1-carboxamides(thioamides) were obtained. The heterocyclization of the same hydrazides lead to nonfused pyrazolyl-pyrimidines and pyridazinyl-pyrimidines and a series of 3-S-substituted derivatives of fused 1,2,4-triazolo[4,3-c]pyrimidine. The preliminary in vitro tests have shown that among the synthesized compounds there are substances exhibiting growth promoting properties.

Open Access Original Research Article

Thermal Properties, Crystal Structure, and Phase Transition of Racemic CaC4H4O6•4H2O Single Crystals

T. Fukami, S. Hiyajyo, S. Tahara, C. Yasuda

Chemical Science International Journal, Page 1-11
DOI: 10.9734/ACSJ/2016/28258

Single crystals of racemic calcium tartrate tetrahydrate, CaC4H4O6·4H2O, were grown at 308 K by a gel method using silica gel as the medium of growth. Differential scanning calorimetry, thermogravimetric-differential thermal analysis, and X-ray diffraction measurements were performed on the single crystals. The space group symmetry (triclinic, P1(__)) and structural parameters were determined at room temperature. The O–H–O hydrogen-bonding networks formed between adjacent C4H4O6 molecules, and between C4H4O6 and H2O molecules, were found to extend along the c-axis and [01(__)1] directions, respectively. A phase transition, driven by intramolecular proton transfer between three possible positions in the vicinity of O atoms, was found to occur at around 310 K. Weight losses due to thermal decomposition of racemic CaC4H4O6·4H2O occurred in the temperature range of 300–1200 K. The weight losses during decomposition were suggested to be caused by the evaporation of bound water molecules and the evolution of 2H2CO, (1/2)O2, and 2CO gases.

Open Access Original Research Article

Physico-chemical Quality of Harvested Rainwater from Some Settlements in Uyo, Nigeria

E. A. Moses, I. I. Uwah, G. A. Ebong

Chemical Science International Journal, Page 1-9
DOI: 10.9734/ACSJ/2016/27113

The use of harvested rainwater for domestic purposes is on the increase in Nigeria, as public water is inadequate as a result of population increase. This study sought to determine the quality of harvested rainwater from some settlements in Uyo, Nigeria, and assess the suitability of the water for domestic household use. Harvested rainwater samples were collected from selected household tanks at Ikot Ntuen Oku, Afaha Oku, Ikot Oku, Mbiabong and Ifa Atai areas of Uyo. Analyses for physico-chemical parameters including pH, electrical conductivity, total dissolved solids, turbidity, total hardness, total alkalinity and acidity, dissolved oxygen, total suspended solids, were done using standard APHA methods. Trace metals were measured using atomic absorption spectrophotometric techniques. The physicochemical parameters measured were below the WHO limits for portability except for dissolved oxygen. The pH values recorded ranged from 5.54 to 6.38 with an overall mean of 5.90; TDS levels ranged from 9.68 to 15.02 mg/l with an average value of 11.8 mg/l while the turbidity values ranged from 2.3 to 3.8NTU. For the nutrients, nitrate levels ranged from 0.97 to 2.1 mg/l with a mean of 1.55 mg/l while the chloride levels ranged between 2.12 and 4.42 mg/l with a mean value of 3.65 mg/l. Levels of trace metals were within WHO recommended limits except for Fe, Cd, and Cu. Some of the results indicated that Cr level was 0.001 mg/l for all sampling points while Zn levels ranged from 1.04 to 1.75 mg/l with a mean value of 1.44 mg/l. Correlation studies showed that Fe was from natural sources while Cr, Mn, Cu, Zn and Cd were from anthropogenic sources. These results indicated expected adverse effects from the consumption of the harvested rainwater with respect to Fe, Cd and Cu. Appropriate treatment of the rainwater to improve quality before use is recommended. This will help improve the water quality and provide portable water for households in the communities.

Open Access Original Research Article

Turbidity and Acidity as Monitoring Parameters in the Purification of Moringa oleifera Oil for Biodiesel Production

Francisco Sávio Gomes Pereira, Alexandre Ricardo Pereira Schuler, Ana Maria Ribeiro Bastos da Silva, Chesque Cavassano Galvão, Rafael do Nascimento Pereira, Nelson Medeiros de Lima Filho, Valdinete Lins da Silva

Chemical Science International Journal, Page 1-9
DOI: 10.9734/ACSJ/2016/28799

Turbidity and Acidity as Monitoring Parameters in the Purification of Moringa oleifera Oil for

Biodiesel Production

This study had as aim the analytical monitoring made during the purification applied to the mixed crude oil extracted from the Moringa oleifera Lamarck seeds by pressing and by hexane extraction. The crude (by pressing, by solvent extraction and mixed) and purified oils were characterised in saponification index, iodine value, acidity index, peroxide index, water content, turbidity, specific mass and kinematic viscosity. Turbidity, an innovative parameter for oleaginous analytical evaluation, had a great influence on clarification, being of 31.1 NTU for the mixed crude oil and of 2.1 NTU for purified oil, corresponding to the removal of 93.16% of colloids. The acidity index of 18.1 mgKOH/g for mixed crude oil was mitigated to 0.2 mgKOH/g for the purified oil, with the removal of 98.62% of the acid species. Turbidity and the acidity index are analytical parameters of simple and efficient methodology of purification of the moringa oil as an acceptable feedstock for biodiesel production. The analytical monitoring techniques and treatments employed in this oil can be extended to saponifiable oils and fats, of vegetable or animal origin, crude or residual, for biodiesel production or for industrial use that require refined material.