bluuebunny/crossref_metadata_2025 huggingface dataset:
Adsorption of Phenol and Chlorophenol Mixtures on Silicalite-1 Determined by GC-MS Method
Authors: Ortiz-Arzate Zareth , Jiménez-Bravo Thelma S , Sánchez-Flores Norma A. , Pacheco-Malagón Graciela , Bulbulian Silvia , Rivero Ignacio A.
Published: April 2018

A method is presented in which gas chromatography coupled with mass spectrometry (GC-MS) allows quantitative simultaneous detection of mixtures of phenol (Ph), 2-chlorophenol (2-CPh), 3-cholorphenol (3-CPh), and 4-cholorophenol (4-CPh) in aqueous mixtures after being adsorbed on silicalita-1, utilizing selected-ion monitoring (SIM) and full-scan modes mass selective detection. GCMS with SIM at m/z = 64 and m/z = 128 showed good detection selectivity for mixtures of Ph, 2-CPh and 3-CPh (M1), and 2-CPh and 4-CPh (M2). Silicalita-1 was obtained from an amorphous organo-alumino-silicic gel from rice husk, an abundant and low cost agricultural waste residue that is readily available in large quantities. This product was used as a sorbent for solid phase extraction of organic analytes from aqueous solutions. The adsorption of the three chlorophenol isomers, ortho-, meta-, and para-, by silicalite-1 has been studied independently, showing that meta- and para-chlorophenol isomers are adsorbed more than ortho-chlorophenol. However the adsorption behavior of mixtures of these isomers was not reported. In this work, it was found that when the ortho-isomer is mixed either with meta or para-chlorophenol, considerable differences were observed in the adsorption process; in the studied mixture, the ortho-isomer was adsorbed more than the meta-and para-chlorophenol.
Smart pH/temperature Sensitive Hydrogels with Tailored Transition Temperature
Authors: Salgado-Rodríguez Rodolfo , Licea-Claverie Ángel , Zizumbo-López Arturo , Arndt Karl-Friedrich
Published: April 2018

Dual pH- and temperature-sensitive hydrogels have been prepared based on N-isopropylacrylamide (NIPAAm) and either potassium 5-methacryloyloxy-pentanoate (M4K) or potassium11-methacryloyloxy-undecanoate (M10K) as comonomers. The gels containing M10K (longer methylene chain) showed a slightly lower swelling capacity than the gels containing M4K. Hydrogels were produced with specific phase transition temperature (Tcr) in the range from 12 to 76 oC for NIPAAm-C4 hydrogels (containing M4K) and from 16 to 36 oC for NIPAAm-C10 hydrogels (containing M10K) by controlling: the type and comonomer content, and the pH of water. The type of transition changes from discontinuous (below the critical pH of the acid comonomer) to continuous (above de critical pH of the acid comonomer). The title hydrogel materials are promising candidates for biomedical applications.
Cyclic C-F-Metal Containig Species. Solid State and Computational Examples
Authors: Arroyo Carranza Maribel , Torrens Miquel Hugo
Published: April 2018

This article examines the results of research published between 2000 and 2012, which found experimental evidence of cyclic species containing the fragment carbon-fluorine-transition metal. 25 Examples (numbered throughout this paper) with 20 different metals and a wide variety of chemical environments have been gathered. A similar analysis brings together almost 40 transitional states and intermediates resulting from theoretical work studying the transition metal mediated carbon-fluorine bond activation. Among other aspects, this review is useful to recognize the specific characteristics which determine whether the C-F activation process is carried out through a concerted process, a mechanism assisted by auxiliary ligands or by free radicals.
Electrochemical Study of the Complex [Cu(pdto)(H2O)]2+ (pdto =1,8-bis-(2-pyridyl)-3,6-dithiaoctane) in the Presence of the Superoxide. Toward an Electrochemical Method to Measure SOD Activity
Authors: Manzanera-Estrada Mayra , Hernández Ayala Luis Felipe , Osorio-Monreal Guadalupe , García-Ramos Juan Carlos , Ortiz-Frade Luis
Published: April 2018

This work presents the electrochemical characterization of Cu(NO3)2•2.5H2O, [Cu(pdto)H2O](PF6)2 and superoxide ion in DMSO. The electrochemical processes Cu(II) + 2e → Cu(0), [Cu(pdto)(H2O)]2+ + 1e → [Cu(pdto)]+, [Cu(pdto)]+ + 1e → Cu(0), O2 •- ↔ O2 + 1e-, and O2•- + 1e + H+ → OOH- were identified. The electrochemical response of a mixture of the complex [Cu(pdto)(H2O)]2+ with superoxide was studied and, according to this result, it was possible to establish a simple methodology that indicates if a compound presents a superoxide dismutase (SOD)-like mechanism.
New Isoniazid Complexes, Promising Agents Against Mycobacterium tuberculosis
Authors: Poggi Mariana , Barroso Rafael , Costa-Filho Antonio José , Barbosa de Barros Heloisa , Pavan Fernando , Leite Clarice Queico , Gambino Dinorah , Torre María Helvecia
Published: April 2018

Tuberculosis (TB) is a public health disease that produces several million deaths annually worldwide. Due to this critical situation and the appearance of drug-resistant microbial strains, innovation in TB drug discovery is a research priority. In this work, the synthesis and characterization by elemental analysis, hermogravimetry, conductimetric measurements and spectroscopies UV-Vis, IR and EPR of [Cu(INH)(H2O)]SO4⋅2H2O (Cu-INH) and [CoCl(INH)2(H2O)] Cl⋅2.5H2O (Co-INH) complexes with isoniazid (INH) are reported. Besides, the lipophilicity, the activity against Mycobacterium tuberculosis (MICCu-INH = 0.78 μg/mL and MICCo-INH = 0.19 μg/mL) and the cytotoxicity (IC50 = 48.8 and 625 μg/mL for the copper and cobalt complexes, respectively) were measured and the selectivity index (62.5 for Cu-INH and 3205 for Co-INH) was calculated. These results indicate that these complexes are good candidates for further studies.
Antineoplastic Evaluation of Two Mixed Chelate Copper Complexes (Casiopeínas®) in HCT-15 Xenograft Model
Authors: Bravo-Gómez María Elena , Hernández de la Paz Ana Laura , Gracia-Mora Isabel
Published: April 2018

Casiopeínas® is a family of copper complexes with the general formulae [Cu(N-N)(N-O)]NO3 and [Cu(N-N)(O-O)]NO3; where N-N = substituted aromatic diimine (2,2’-bipyridine (bipy) or 1,10-phenanthroline (phen)); N-O = α-aminoacidate or a peptide; and O-O = acetylacetonate (acac) or salicylaldehydate. These compounds have shown antiproliferative activity in vitro and antitumor activity in several mouse models with promissory results. Efforts have been done in order to understand the role played by ligands in the biological activity. With the aim of finding out the effect of secondary ligand (N-O or O-O), two of the most active complexes in vitro assays were selected to perform in vivo study on HCT-15 colon adenocarcinoma xenograft model. Both complexes, [Cu(3,4,7,8-tetramethyl-1,10-phen anthroline)(glycinato)]NO3 (1) and [Cu(3,4,7,8-tetramethyl-1,10-phenanthroline)(acetylacetonato)]NO3 (2) share the same diimine ligand and the secondary ligand changes from glycinate (gly) to acac. Results show that 2 is effective to reduce tumor size but 1 does not achieve the values required according to protocols, revealing an important difference between compounds attributable to change of ligand from gly to acac.
A Therapeutic System of 177Lu-labeled Gold Nanoparticles-RGD Internalized in Breast Cancer Cells
Authors: Luna-Gutiérrez Myrna , Ferro-Flores Guillermina , Ocampo-García Blanca E. , Santos- Cuevas Clara L. , Jiménez-Mancilla Nallely , De León-Rodríguez L. M , Azorín-Vega Erika , Isaac- Olivé Keila
Published: April 2018

The aim of this research was to evaluate the in vitro potential of 177Lu-labeled gold nanoparticles conjugated to cyclo-[RGDfK(C)] peptides (177Lu-AuNP-c[RGDfK(C)]) as a plasmonic photothermal therapy and targeted radiotherapy system in MCF7 breast cancer cells. Peptides were conjugated to AuNPs (20 nm) by spontaneous reaction with the thiol group of cysteine (C). After laser irradiation, the presence of c[RGDfK(C)]-AuNP in cells caused a significant increase in the temperature of the medium (50.5 °C, compared to 40.3 °C without AuNPs) resulting in a significant decrease in MCF7 cell viability down to 9 %. After treatment with 177-AuNP-c[RGDfK(C)], the MCF7 cell proliferation was significantly inhibited.
Synthesis and Anticancer Activity of Gold(I)-Chloroquine Complexes
Authors: Navarro Maribel , Castro William , González Sorenlis , Abad María Jesús , Taylor Peter
Published: April 2018

Two new gold(I) -chloroquine complexes, Au(CQ)(Cl) (1) and Au(CQ)(tgta) (2), were prepared and their most probable structure were established through a combination of different spectroscopic and analytical techniques. Their interaction with two important targets of action, DNA and thioredoxin reductase (TrxR), were nvestigated. These studies showed that complexes 1 and 2 displayed two types of interaction with DNA, covalent binding through the metal center, and additionally a non-covalent interaction that is electrostatic in the case of complex 1, but intercalative for complex 2, which is similar to that displayed by free CQ. The experimental data indicated that these gold-CQ complexes also possess the ability to inhibit TrxR. These results led us to test their cytotoxicity against 6 tumor cell lines. The complexes displayed cytotoxic activity against the PC-3, SKBR-3, HT-29, LoVo and B16/BL6 lines. These finding suggest that gold(I)-CQ compounds, particularly [Au(CQ)(PPh3)]PF6, are promising chemotherapeutic alternatives in the search of anticancer agents.
Blood to Plasma Ratio, Short-Term Stability and Plasma Protein Binding of Casiopeína IIgly, a Copper (II) Based Compound with Antineoplastic Activity
Authors: Cañas-Alonso Roberto Carlos , Fuentes-Noriega Inés , Ruiz-Azuara Lena
Published: April 2018

Casiopeína IIgly is a mixed chelate coordination compound with copper (II) core that has shown important antineoplastic activity, even in some resistant cellular lines to Cisplatin. In this work, preclinical studies as blood to plasma ratio, plasma protein binding, short-term stability in blood and pharmacokinetics of this coordination complex are reported. The results indicate that Casiopeína IIgly is stable in blood at least for 6 hours at 37 °C. Also, this compound exhibits an important accumulation in whole blood rather than plasma fluid, a high plasma protein binding (>90%) as well as short half-life (47 min).
Statistical Treatment of Bleaching Kaolin by Iron Removal
Authors: Hernández Hernández Román Ángel , Legorreta García Felipe , Hernández Cruz Leticia Esperanza , Martínez Luévanos Antonia
Published: April 2018

In the present study, oxalic acid was used as a leaching reagent to remove iron from a kaolin mineral. Statistical analysis was conducted to determine the most influential factors in the dissolution of iron from the kaolin mineral. Our goal was ferric iron solubilization and its reduction to ferrous iron to improve the iron removal in the acid medium. Leaching experiments were conducted at atmospheric pressure. A two-level factorial design of the type 24 was utilized. The dependent variable was the percentage of dissolved iron, and the dependent variables in this study were acid concentration (0.35 and 0.50 M), temperature (75 °C and 100 °C), leaching time (2 and 4 h), and pH (1.5 and 2.5). An analysis of variance revealed that the effects of the factors temperature (b), pH (d), and the combined effects of temperature and time (bc) resulted in the maximum dissolution of iron of 88% at 100 °C, giving a kaolin mineral with a whiteness index 93.50%.
Zeolite Encapsulated Fe-poprhyrin for Catalytic Oxidation with Iodobenzene Diacetate (PhI(OAc)2)
Authors: Karimipour Gholamreza , Rezaei Maryam , Ashouri Davoud
Published: April 2018

meso-Tetrakis(3-pyridyl)porphyrinatoiron(III) chloride encapsulated on NaY Zeolite [Fe(T-3-PyP)@NaY] was synthesized as a heterogeneous “ship-in-a-bottle” type catalyst and characterized by Fourier transform infrared (FT-IR), atomic absorption (AA), diffused reflectance UV-Vis (DR UV-Vis), X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis. The catalytic activity of Fe(T-3-PyP)@NaY was examined for the epoxidation of cyclohexene by PhI(OAc)2 in CH3CN/H2O (5:1) and compared to that of Fe(T-3-PyP) as a homogenous catalyst. We found that the heterogeneous catalyst Fe(T-3-PyP)@NaY was stable and reusable for several times, and provided a mild condition and exhibited high activity and selectivity in the oxidation of alkenes to epoxides(16-94%). As representative examples for the use of Fe(T-3-PyP)@NaY/ PhI(OAc)2 in organic oxidations, oxidation of 4-nitrobenzylalcohol to 4-nitrobenzaldehyde (97 %), oxidative dehydrogenation of diethyl 4-(2,6-dichlorophenyl)-2,6-dimethyl- 1,4-dihydro-3,5-pyridinedicarboxylate to the corresponding pyridine (100 %), diphenylacetic acid to benzophenone (64 %) was achieved.
Photocatalytic Degradation of Nitrobenzene Using Nanocrystalline TiO2 Photocatalyst Doped with Zn Ions
Authors: Reynoso-Soto Edgar Alonso , Pérez-Sicairos Sergio , Reyes-Cruzaley Ana Patricia , Castro-Riquelme Christian Leonardo , Félix-Navarro Rosa María , Paraguay-Delgado Francisco , Alonso-Núñez Gabriel , Lin-Ho Shui Wai
Published: April 2018

Photocatalysis is a method widely used in the degradation of organic pollutants of the environment. The development of new materials is very important to improve the photocatalytic properties and to find new applications for TiO2 as a photocatalyst. In this article we reported the synthesis of a photocatalyst based on TiO2 doped with Zn2+ ions highly efficient in the degradation of nitrobenzene. The results of photocatalytic activity experiments showed that the Zn2+ doped TiO2 is more active than un-doped TiO2 catalyst with an efficiency of 99% for the nitrobenzene degradation at 120 min with an apparent rate constant of 35 × 10-3 min-1.
Development and Validation of HPLC Method for Simultaneous Determination of Ceftriaxone and Cefaclor in Commercial Formulations and Biological Samples
Authors: Shah Jasmin , Rasul Jan M. , Shah Sultan , Naeem Khan M.
Published: April 2018

A reversed phase high performance liquid chromatographic method has been developed for the simultaneous determination of cefaclor and ceftriaxone cephalosporin antibiotic. The developed method has been validated and applied to mixtures of the commercial formulation and spiked human plasma. A mediterranea C18 column (4.6 × 250 mm) was used with isocratic solvent delivery system and UV-visible detector. Different experimental parameters like solvent composition (acetonitrile: methanol: triethyl amine buffer 1:1:2 (v/v), flow rate of mobile phase (0.6 mLmin-1), pH of the buffer (7), and wavelength (260 nm) were optimized for effective separation and esolution of the analyte peaks. The separation was achieved in 6 min with retention times of 4.94 ± 0.056 min and 3.39 ± 0.022 min for cefaclor and ceftriaxone respectively. The linear range for both the studied drugs was found to be 0.5-250 μgmL-1 with r2 of 0.9987 (cefaclor) and 0.9997 (ceftriaxone). The limit of detection (3.3 σ/S) was found to be 2.34 × 10-2 μgmL−1 and 1.70 × 10−2 μgmL-1, respectively, for cefaclor and ceftriaxone. Similarly limit of quantification (10σ/S) was 7.10 × 10−2 μgmL-1 for cefaclor and 5.15 × 10−2 μgmL-1 for ceftriaxone. The chromatographic procedure was applied to commercial formulations and spiked human plasma and the results were compared with literature HPLC method.
NMR and Theoretical Studies on the Conformational Preferences of Some Non-metal Coordinated N-Enoyl Systems Attached to Common Chiral Auxilaries
Authors: Morales-Nava Rosmarbel , Ramírez-Solís Alejandro , Fernández-Zertuche Mario
Published: April 2018

We report a systematic study of a series of N-enoyl systems attached to common oxazolidin-2-ones, oxazolidine-2-thiones and thiazolidine-2-thiones chiral auxiliaries in order to determine the most stable conformation of these compounds. 1H NMR studies show an anti-s-cis structure as the most stable conformation for these series of compounds. Density Functional Theory geometry optimizations and vibrational analysis using the b3lyp exchange-correlation functional with the standard 6-31g** basis sets were done, including solvent effects (chloroform and toluene). Gibbs free energy differences show that the anti-s-cis structures are the most stable conformers lying, on average, ca. 6 kcal/mol lower in energy than the syn-s-cis conformers, widely used to explain the structure and reactivity of N-enoyl systems.
Plackett-Burman Factorial Design for the Optimization of a Spectrophotometric Flow Injection Method for Phenol Determination in Tap and Bottled Water Using 4-Aminoantipyrine
Authors: Carrillo-Cedillo E. G. , Haro-Vázquez M. P. , Díaz Trujillo G. C. , Cañizares-Macías M. P.
Published: April 2018

Plackett-Burman and Quarter fraction 25-2 factorial designs were applied to evaluate a spectrophotometric flow injection method in order to determine phenol in water by using 4-aminoantipyrine (4-aap) as derivatizing reagent. With a minimum number of experiments, the designs enabled the best conditions for phenol analysis: 80 cm and 180 cm reactors; flow-rates being: NH3 1.0 mL min-1; 4-aap 0.35 mL min-1 and K3[Fe(CN)6] 0.35 mL min-1, [NH3] 0.064 mol L-1, [4-aap] 9.84 × 10−3 mol L-1, [K3[Fe(CN)6]] 0.02 mol L-1, and an injection volume of 200 μL. With the optimized method it was possible to increase the lineal range from 0.3 μg mL-1 to 30 μg mL-1 and also to quantify the maximum allowable phenol concentration in water in comparison with other standard and flow injection methods whose lineal range are from 0.5 μg mL-1 to 20 μg mL-1 and from 0.5 μg mL-1 to 16 μg mL-1, respectively. The detection limit was of 0.13 μg mL-1 and the regression coefficient was of 0.9999, making possible a throughput of 36 determinations an hour with a minimum consume of reagent. With the proposed method, a distillation step was not necessary to remove sulfates but, when the sulfate:phenol ratio was higher than 83, the analytical signal for phenol increased 8%, but hypochlorite interfered with the signal when the ypochlorite:phenol ratio was higher than 1.
New Energetic Materials Derived from Pentaerythritol, Diethanolamine, and Chloramphenicol
Authors: Romero Miguel Ángel
Published: April 2018

Four new compounds with potential use as low-sensitivity secondary explosives were prepared from readily available and inexpensive starting materials: pentaerythritol, diethanolamine, and chloramphenicol. Experimental and theoretical properties for each new compound are described, as well as their potential use as energetic materials.
Synthesis, Chemical Structure Elucidation and Biological Studies on the Effect of Some Vital Metal Ions on Lisinopril
Authors: Zaky M. , El-Sayed Mohamed Y. , El-Megharbel Samy M. , Abo Taleb Sameh , Refat Moamen S.
Published: April 2018

Complexes of lisinopril as a pharmaceutical ligand with Ca(II), Mg(II), Zn(II), Fe(III) and VO(II), were synthesized and characterized by microanalysis, conductance, infrared and thermogravimetric (TGA/DTG and DTA) measurements. The lisinopril ligand acts as a monodentate feature via one carboxylate oxygen atom. Lisinopril and their complexes have been checked against some kinds of bacteria and fungi which gave a significant effect. The kinetic thermodynamic parameters such as: activation of E*, ΔH*, ΔS* and ΔG* were estimated using Coats and Redfern as well as Horowitz-Metzger equations.
A Green Approach to the Production of 2-pyridone Derivatives Promoted by Infrared Irradiation
Authors: Hernández Fernando , De la Cruz Fabiola , López Julio , Peña Eduardo , Delgado Francisco , Alcaraz Yolanda , Robles Juvencio , Martínez-Alfaro Minerva , Vázquez Miguel A.
Published: April 2018

An alternative is presented for promoting a reaction with infrared irradiation to obtain different 4-aryl-3-cyano-5-ethoxycarbonyl-6-methyl-2-pyridone derivatives 9a-k. The process was carried out with a green approach from the corresponding 4H-pyrans, using mild reaction conditions and infrared irradiation as the energy source. In the first stage, the reaction produced 1,2,3,4-tetrahydropyridin-2-one derivatives 8a-k, followed by an oxidative step to afford the target molecules in good yields. The structure of products 9a-k was confirmed by FT-IR, 1H NMR and 13C NMR spectroscopic techniques and X-ray diffraction. It was found that the efficiency of the reaction depends on the catalyst and the solvent, as well as on the aldehyde substituents.
Comparison Between Antioxidant Activities of Phenolic Extracts from Mexican Peanuts, Peanuts Skins, Nuts and Pistachios
Authors: Rosales-Martínez Patricia , Arellano-Cárdenas Sofía , Dorantes-Álvarez Lidia , García-Ochoa Felipe , López-Cortez Ma del Socorro
Published: April 2018

Recently, several works have been done in order to study antioxidant compounds like resveratrol present in oilseeds since they are able to protect from cells damage related to heart disease and cancer. In the present research a chemical analysis and the identification of bioactive compounds of peanuts, nuts and pistachios varieties were carried out. The walnut variety showed the highest content of total phenolic compounds (1404 ± 23 mg GAE/100 g) and antioxidant capacity (191 ± 4.2 μmol TE/g). Phenolic compounds resveratrol, catechin, epicatechin and quercetin were identified in all samples.
Eremophilanes and Pyrrolizidine Alkaloids of Senecioneae Species
Authors: Pérez-Castorena Ana L. , Arciniegas Amira , Villaseñor José Luis , Romo de Vivar Alfonso
Published: April 2018

The chemical study of two species of the tribe Senecioneae afforded two eremophilanes and two pyrrolizidine alkaloids from Senecio subauriculatus and four modified eremophilanes from Roldana oaxacana. The chemistry of these species is in accord with that reported for species of Senecio and Roldana studied so far, and therefore, with the already described for the tribe Senecioneae.
Electrooxidation of Diclofenac in Synthetic Pharmaceutical Wastewater Using an Electrochemical Reactor Equipped with a Boron Doped Diamond Electrode
Authors: Coria Gabriela , Nava José L. , Carreño Gilberto
Published: April 2018

This paper deals with the degradation of diclofenac by electrochemical oxidation in NaClO4 medium at neutral pH using a FM01-LC reactor equipped with a boron doped diamond electrode (BDD). Microelectrolysis studies were carried out to find the current density domain where hydroxyl radical (•OH) formation is favored, 10 ≤ j ≤ 20 mA cm-2. Electrolysis experiments at mean linear flow velocities of 14.6 ≤ u ≤ 58.4 cm s-1 were performed. The experimental set-up achieved 100% diclofenac mineralization with 78% current efficiency and energy consumption of 2.54 kWh m-3 at j = 15 mA cm-2 and u=29.2 cm s-1.
Construction and Testing of a Novel in-situ Photoelectro-Fenton System Based on an Arrangement of a Carbon Sponge and a Carbon Steel Plate
Authors: González Reyes Ivonne Arely , De Anda Reyes M. E. , Rodríguez Valadez Francisco J. , Manríquez Juan , Bustos Erika , Rodríguez Adrian , Godínez Luis A.
Published: April 2018

A novel photoelectro-Fenton system was built by coupling a carbon sponge (CS) with a carbon steel plate (CSP). When this system contacts a solution containing orange II dye (OGII) under ultraviolet (UV) irradiation, 68% of the solution color was removed compared with 0% without UV irradiation. The tests indicate that the CS-CSP arrangement releases iron ions, a phenomenon associated with the removal of 23% of the solution color, a percentage similar to that obtained when Fe2+ and Fe3+ salts are directly placed into the dye solution. The identification of oxidizing free radicals and the color removal percentages indicate that the CS-CSP coupling can operate as in situ Fenton process.
Electrochemical Behavior of Metamitron Herbicide at the Interface of Two Immiscible Electrolyte Solutions
Authors: Reyes-Reyes Alma Gricel , Amador-Hernández Judith , Velázquez-Manzanares Miguel
Published: April 2018

The electrochemical behavior of the metamitron herbicide at the water|1,2-dichloroethane interface was studied by means of cyclic voltammetry and Electrochemical Impedance Spectroscopy. The results show that metamitron extraction across the interface was pH dependent. The curves capacitance-potential shown that the presence of a lipid monolayer inhibits the metamitrone transport across the interface. In this paper the equilibrium partition of metamitron across the interface of two immiscible electrolyte solutions is discussed.
Electrochemical Hydrogen Peroxide Production in Acidic Medium Using a Tubular Photo-reactor: Application in Advanced Oxidation Processes
Authors: Peralta-Hernández Juan M. , Godínez Luis A.
Published: April 2018

This paper describes the results obtained in the design and characterization of a tubular electrochemical reactor. The set-up was employed for on-site hydrogen peroxide (H2O2) production in an acidic medium (pH 3) to promote three electrochemical advanced oxidation processes (EAOP): electro-Fenton (EF), photoelectro-Fenton (PEF) and photocatalysis treatment (PT). These processes were evaluated by their abilities to degrade a commercial dye, Orange-II (OGII), in solution using total organic carbon (TOC) removal and high performance liquid chromatography (HPLC). To have free solutions of iron in the EF and PEF systems, a NafionTM membrane with dispersed iron was prepared. For use in photocatalysis, electrodes with a large superficial area were prepared by coating carbon cloth fiber supports with titanium dioxide (TiO2) using the electrophoretic (EP) method. In this work, wastewater samples with a large number of microorganisms (coliform bacteria) were treated with this new reactor design.
Removal of Color and Chemical Oxygen Demand Using a Coupled Coagulation-Electrocoagulation-Ozone Treatment of Industrial Wastewater that Contains Offset Printing Dyes
Authors: Roa-Morales Gabriela , Barrera-Díaz Carlos , Balderas-Hernández Patricia , Zaldumbide-Ortiz Francisco , Reyes Perez Horacio , Bilyeu Bryan
Published: April 2018

Industrial offset printing processes generate wastewater with highly colored obtaining values of 5x106 Pt-Co units and great values of chemical oxygen demand (COD) 5.3x10-5 mg L-1. Thus, conventional technologies such as biologicals treatment fail in reaching the discharge limits. In this research, a sequential treatment was applied: coagulation with aluminum hydroxychloride (AHC), electrocoagulation with Al anodes and finally ozonation. Optimal conditions are found when adding 20 mg L-1 AHC, followed by electrocoagulation at 4 A for 50 min, and finally alkaline ozonation for 15 min, resulting in an overall color removal of 99.99% color and 99.35% COD.
Biodiesel synthesis from Pongamia Pinnata oil over modified CeO2 catalysts
Authors: Zaheeruddin Mohamed Shamshuddin Sathgatta , -- Venkatesh , Shyamsundar Manjunatha , Thammannigowda Vasanth Vanagoor
Published: April 2018

This study investigates the use of CeO2, ZrO2, MgO and CeO2-ZrO2, CeO2-MgO, CeO2-ZrO2-MgO mixed oxides as solid base catalysts for the transesterification of Pongamia Pinnata oil with methanol to produce biodiesel.  SO42-/CeO2 and SO42-/CeO2-ZrO2 were also prepared and used as solid acid catalysts for esterification of Pongamia pinnata oil (P-oil) to reduce the % of free fatty acid (FFA) in P-oil. These oxide catalysts were prepared by an incipient wetness impregnation method and characterized by techniques such as NH3-TPD for surface acidity, CO2-TPD for surface basicity and powder X-ray diffraction for crystalinity.  The effect of nature of the catalyst, methanol to P-oil molar ratio and reaction time in esterification as well as in transesterification was investigated.  The catalytic materials were reactivated & reused for five reaction cycles and the results showed that the ceria based catalysts have reasonably good reusability both in esterification and transesterification reaction.  The test results also revealed that the CeO2-ZrO2 modified with MgO could have potential for use in the large scale biodiesel production.
A Theoretical Study of Chemical Reactivity of Tartrazine Through DFT Reactivity Descriptors
Authors: Mendoza Huizar Luis Humberto
Published: April 2018

In this work we have calculated global and local DFT reactivity descriptors for tartrazine at B3LYP/6-311++G (2d,2p) level. Global reactivity descriptors such as ionization energy, molecular hardness, electrophilicity, and total energies were calculated to evaluate the tartrazine reactivity in aqueous and gas conditions. Local reactivity was evaluated through the Fukui function. The influence of the solvent was taken into account with the PCM model. The results indicate that the solvation process modifies the reactivity descriptors values. From our results, it was found that an electrophilic attack allows a direct cleavage of the N=N bond. If a nucleophilic attack is considered as initial attack, it is necessary a second attack by free radicals or electrophiles to cleave the N=N bond. In the case of an initial attack by free radicals, tartrazine requires a subsequent nucleophilic attack to cleave the N=N bond.
Biocompatibility Evaluation of Electrospun Scaffolds of Poly (L-Lactide) with Pure and Grafted Hydroxyapatite
Authors: Cornejo-Bravo José Manuel , Villarreal-Gómez Luis Jesús , Vera-Graziano Ricardo , Vega-Ríos María Raquel , Pineda-Camacho José Luis , Almaraz-Reyes Horacio , Mier-Maldonado Paris Astrid
Published: April 2018

The objective of this work was to evaluate the biocompatibility of scaffolds of poly(L-lactide) with pure and grafted hydroxyapatite, at various concentrations of reinforcement. The biocompatibility tests were carried out in vivo in Wistar rats by implanting the material into the subcutaneous and muscle tissues from 1 to 14 weeks and evaluating the surrounding tissue stained with hematoxylin-eosin. For in vitro assays, MTT and neutral red assay were used to evaluate any cytotoxicity in Mioblast Muscle C2C12 Cells (ATCC® CRL-1772™) and Bovine Coronary Artery Endothelial Cells (BCAEC); Escherichia coli and Staphylococcus aureus were used to evaluate bacterial adhesion. All variants of scaffolds provoked a mild inflammatory response, without showing necrosis. No evidence of cytotoxicity was presented in cell viability tests and good bacterial cell adhesion was visualized for all of the materials studied.
Chemical Composition and Antibacterial Activity of Essential Oils Extracted from Plants Cultivated in Mexico
Authors: Chauvin Anne-Laure , Rodríguez Flores Crecencio , Pennec Alizé , Nugier-Chauvin Caroline , Daniellou Richard , Herrera-Estrella Luis
Published: April 2018

Samples of lavender, rosemary and laurel essential oils obtained from plants cultivated in Mexico were analysed by GC-MS using a non polar capillary column. Characterisation of individual components was performed using a commercial mass spectrometry library, and 53 components were identified. The analysis of bioactive compounds highlighted a 5 and 2-fold increased quantity of potent antibacterial 1,8-cineole (46.5%) and camphor (12.3%) in lavandin “provence”, compared to the French cultivars. It also showed a 3- and 2-fold increase in camphor and linalool concentration in rosemary and laurel compared to the average level, making them promising alternatives for medicinal treatment. Strains of Gram-positive and Gram-negative bacteria were analyzed for their susceptibility to these essential oils using the agar disc diffusion method and their antimicrobial activity was demonstrated. To our knowledge, this is the first report on antibacterial activity of lavender essential oil, recently added to the Mexican pharmacopeia, against Mycobacterium smegmatis (Mc Rv 3782 PW2).
Substituent and Solvent Effects on the Electronic and Structural Properties of Silacyclopropylidenoids
Authors: Azizoglu Akin
Published: April 2018

The isomeric structures, energies, and properties of the substituted silacyclopropylidenoids, SiC2H3RLiBr (R= –H, –CH3, –SiH3, –CN, –OH, –NH2), were studied by ab initio calculations at the MP2/6-311+G(d,p) level of theory. The calculations indicate that each of SiC2H3RLiBrs for R= –H, –CH3, –SiH3, –CN, –OH, –NH2 has three stationary structures: silacyclopropylidenoid (S), tetrahedral (T1 or T2), and inverted (I). The conductor–like polarizable continuum model (CPCM) using various solvents (dimethyl sulfoxide (ε = 46.7), acetone (ε = 21.0), tetrahydrofuran (ε = 7.5), and diethyl ether (ε = 4.3)) has been applied to compute single point energies for title molecules. In addition, the molecular electrostatic potential maps, natural bond orbitals, and the frontier molecular orbitals of substituted silacyclopropylidenoids were calculated.
Molybdenum Oxide Supported on Silica (MoO /SiO ): An Efficient and Reusable Catalyst for the Synthesis of 1,8-dioxodecahydroacridines Under Solvent-free Conditions
Authors: Khojastehnezhad Amir
Published: April 2018

Silica supported molybdenum oxide (MoO3/SiO2) was found to be an efficient, eco-friendly and heterogeneous catalyst for the multicomponent reaction of aromatic aldehydes, dimedone and ammonium acetate or aromatic amines under solvent-free conditions to afford the corresponding 1,8-dioxodecahydroacridines  in high yields. The catalyst can be easily recovered and reused for several times without considerable loss of activity. Furthermore, the present method offers several advantages, such as an easy experimental and work-up procedures, short reaction times and good to excellent yields.
Secondary Metabolites from Asclepias otarioides
Authors: Maldonado Emma
Published: April 2018

Chemical study of the aerial parts of Asclepias otarioides led to the isolation of four pentacyclic triterpenes and one cardenolide glycoside. This is the first report on the occurrence of the triterpenes 1, 3, and 4 in the genus Asclepias.
Stereochemical Investigation of a Novel Biological Active Substance from the Secondary Metabolites of Marine Fungus Penicillium chrysogenum SYP-F-2720
Authors: Sun Tiemin
Published: April 2018

The chemical structure and absolute configuration of anovel benzoic acid (1) which is the secondary metabolites from themarine fungus Penicillium chrysogenum SYP-F-2720, has been determinedby experimental spectroscopic data and quantum chemicalcalculations of its electronic circular dichroism (ECD). The configurationalassignments were further confirmed by the highly consistentspectra between natural compound and synthetic compound whichfrom raw material with a definite configuration. Furthermore, Thetarget compound exhibited more significant anti-inflammatory andanalgesic activities than aspirin when administered at 100 mg/kg,however, it behaved no ulcerogenic effect.
Optimization of Extraction Conditions for Flavonoids of Physalis alkekengi var. franchetii Stems by Response Surface Methodology and Inhibition of Acetylcholinesterase Activity
Authors: Liu Xue-gui , Jiang Fu-yu , Gao Pin-yi , Jin Mei , Yang Di , Nian Zhong-feng , Zhang Zhen-xue
Published: April 2018

The microwave-assisted extraction conditions of flavonoids in Physalis alkekengi. var. franchetii stems were optimized using a L33 Box-Behnken Design. The optimized extraction conditions were determined as follows: 60% for the ethanol concentration, 12.4 for the liquid-to-solid ratio, and 531.4 W for the microwave power, respectively. The yield of the extract obtained under the optimized conditions was 3.85 mg g−1 which was close to the predicted value. In addition, the extract exhibited potent acetylcholinesterase inhibitory activity, with the IC50 value of 11.61 μg mL−1 and a maximal inhibition ratio 89.81%. Both the yield and activity were better than reflux extraction.
A Rapid, One-pot, Multi-component Route to 4,4’-(arylmethylene)bis(3methyl1-1-phenyl-H-pyrazol-5-ols)
Authors: Hassankhani Asadollah
Published: April 2018

A new, efficient and environmentally benign protocol for the one-pot, multicomponent synthesis of 4,4'-arylmethylene-bis(3-methyl-1-phenyl-1H-pyrazol-5-ols) by condensation of aryl aldehydes, phenyl hydrazine and ethyl acetoacetate catalyzed by Ce(SO4)2.4H2O as an ecofriendly catalyst with high catalytic activity and reusability at 125 °C under solvent-free conditions is reported.The reaction proceeds to completion within 5-12 min in 81-98% yield. This new green methodology is of interest due to minimizing the cost of operational hazards and environmental pollution, its excellent yields, short reaction time and high catalyst activity and reusability.
Chemometrics as a Tool in the Study of Lead Toxicity in Rats
Authors: Amador-Hernández Judith
Published: April 2018

In this work, chemometric tools were applied to establish correlations between biomarkers and to identify the most significant ones in relation to acute exposure of Wistar rats to Pb. The metal content in biological matrices (serum, urine, liver, brain, and kidney), biochemical parameters (protein content, activity of the Glutathione S–Transferase enzymes, and urinalysis), apart from morphological measurements of organisms, were estimated in both the exposed and the control groups and submitted to Significance tests, Principal Component Analysis, Hierarchical Cluster Analysis, and Generalized Procrustean Analysis. It could be observed that Pb in serum, but not in erythrocytes, was the biomarker associated with the Pb content in kidney and other parameters related to this organ. In the same way, Pearson correlation coefficients emphasized the relation between Pb in serum and these variables, with the exception of kidney weight. Additionally, Pb in serum was found to be the biomarker with the greatest difference between the control and the exposed groups, which converts it into the most sensitive biomarker in the present study.
Simultaneous Determination of Acetaminophen, Pamabrom and Pyrilamine Maleate in Pharmaceutical Formulations Using Stability Indicating HPLC Assay Method
Authors: Ashfaq Muhammad
Published: April 2018

A simple, specific and accurate stability indicating RPHPLC method was developed for the determination of acetaminophen, pamabrom and pyrilamine maleate simultaneously in pharmaceutical dosage forms. Successful separation of all the components was enacted within 10 min using C18 column with mobile phase of methanol and acidified water (pH 1.8) in the ratio of (27: 73 v/v respectively). Flow rate of the mobile phase was 1.5 mL/min with detection at 300 nm. The method was validated in accordance with ICH guidelines. Response was a linear function of concentration over the range of 50- 150 ????g/mL for acetaminophen, 2.5-7.5 ????g/ mL for pamabrom and 1.5-4.5 ????g/mL for pyrilamine maleate. The method resulted in excellent separation of all the analytes along with their stress induced degradation products with acceptable peak tailing and good resolution. It is therefore can be applied successfully for simultaneous determination of acetaminophen, pamabrom and pyrilamine maleate in pharmaceutical formulations and their stability studies.
Reaction Parameters for Controlled Sonosynthesis of Gold Nanoparticles
Authors: Cabrera-Lara Lourdes I.
Published: April 2018

The synthesis of gold nanoparticles by sonochemical technique has been previously performed with excellent results. The synthesis has been carried out in the presence of citric acid, a strong reducing agent, which allows the nucleation and growth of gold nanoparticles, at the same time that controls particle size. In this work, we report the use of sodium tartrate as a mild reducing agent that allows a better understanding of the effect of the reaction parameters during gold nanoparticle synthesis. A conventional sonication bath (37 kHz) was used for the sonochemical synthesis. This work focuses on the reaction temperature effect and the effect of sodium tartrate concentration. It was confirmed that particle size, and particle morphology is dependent of these two reaction parameters. Equally, colloidal stabilization was related to reaction temperature and sodium tartrate concentration. It was also determined that Ostwald ripening takes place during sonochemical reaction under our conditions, allowing us to understand the mechanism that takes place during synthesis. Gold nanoparticles with main particle size of 17 nm were achieved by this method.
Synthesis of New Dicoumarol Based Zinc Compounds and their Invitro Antimicrobial Studies
Authors: Rehman Sadia , Ikram Muhammad
Published: April 2018

The dicoumarol derivatives were reacted with Zn (II) salt yielding the complexes (1-10) where metal centre was seen to be coordinated with dicoumarols through hydroxyl and carbonyl sites of attachments. All the synthesized compounds were studied spectroscopically using 1H, 13C{1H}-NMR, infrared spectroscopic method, and analytically using ES(+,-)-MS, elemental analyses and conductance studies. The combined NMR and mass spectral data suggested the attachment of two ligands to the zinc (II) centre. Hydroxyl site is deprotonated and take part in charge neutralization of metal center. The synthesized zinc based dicoumarol compounds were screened for antimicrobial activities against Gram negative bacteria Escherichia coli, Salmonella typhus, Agrobacterium tumefaciens, Erwinia carotovora, Pseudomonas aeruginosa, Klebsiella pneumoniae, Gram positive bacteria Staphylococcus aureus, Bacillus subtilis, Bacillus atrophaeus and fungal Strain Candida albicans. All the compounds shown exceptional antimicrobial and antifungal activities.
Convenient Synthesis and Biological Activity of 4-minomethylene 1-phenylpyrazolidine-3,5-diones
Authors: Ahmed Eman A.
Published: April 2018

Reaction of (Z)-4-((dimethylamino)methylene)-1-phenylpyrazolidine-3,5-dione (1) with different nucleophiles is described. Treatment of enaminone 1 with phenylhydrazine led to 3-oxo-N’,2-diphenyl-2,3-dihydro-1H-pyrazole-4-carbohydrazide 7. New enaminone derivatives 2–6 and 12–14 were conveniently obtained in high yields via nucleophilic substitution of the dimethylamino group in enaminone 1 when reacted with o-aminophenol, o-aminothiophenol, ethanolamine, cysteamine hydrochloride, piperidine, morpholine, 2-aminopyridine and glycine. Reaction of enaminone 1 with diaza-nucleophiles, such as hydrazine hydrate, ethylenediamine and o-phenylenediamine, afforded the corresponding bis-enaminones 9–11. Anti-inflammatory and antimicrobial activities of some new products were evaluated. Compounds 1, 2, 4, 7, 12a, and 12b showed high anti- inflammatory activity compared with indomethacin as the reference, while the highest antimicrobial effect was observed in the case of compound 3.
ANALISIS JUMLAH KROMOSOM PADA TRIPLOIDISASI IKAN MAS (Cyprinus carpio Linn) RAS PUNTEN DENGAN LAMA PERENDAMAN KEJUT SUHU PANAS YANG BERBEDA
Authors: Susilo Rahmad Hendro , Farikhah Farikhah , Rahim Andi Rahmad
Published: April 2018

Goldfish (Cyprinus carpio Linn) punten breeds is a type of freshwater fish that has greatpotential in terms of quality and quantity. Seed production from generation to generation hasdecreased quality. An alternative effort was made to maintain the seed quality of geneticengineering with triploidization process using heat shock treatment. The heat shock can preventpolar body II from splitting on eggs during cleavage of meiosis II level resulting in 3Nchromosome or sterile fish. The purpose of this research is to analyze chromosome number intriploidization process of punten breeds fish and to analyze the effect of temperature shockduration on hatching rate of goldfish (Cyprinus carpio Linn) Punten Breeds. This research wasdescriptive research with 2 treatments and 3 replications in each treatment that was heat shocktreatment 40 ºC at minute 2 after fertilization with difference of heat shock duration 1,5 minutes(treatment A) and shock time temperature 2 minutes (treatment B). The parameters observedwere triploid success, hatching rate, survival rate, and growth of of goldfish (Cyprinus carpioLinn) Punten Breeds, analyzed by T-test with 95% confidence interval. The result of heat shockduration of 1.5 minutes showed the percentage of triploid fish 53,57% and shock timetemperature 2 minute 43,64%. The result of T-test of both treatments had no significant effect onall observation parameters but had varied relationship that was enough and inversely related toall observation parameters
PENGARUH KONFORMITAS DAN RISK PERCEPTION TERHADAP SENSATION SEEKING BEHAVIOR PADA REMAJA PENGENDARA SEPEDA MOTOR DI BAWAH UMUR
Authors: Grashinta Aully , Nisa Ummu Khairun
Published: April 2018

Penelitian bertujuan membuktikan pengaruh persepsi resiko sebagai faktor internal individu dan konformitas teman sebaya sebagai faktor eksternal terhadap kecenderungan sensation seeking behavior pada remaja pengendara sepeda motor di bawah umur. Sampel penelitian 201 pengendara sepeda motor berusia 12-16 tahun di Jakarta.Teknik sampling yaitu aksidental. Konformitas diukur dengan modifikasi skala Konformitas Teman Sebaya (Annurfatmah,2014), reliabilitasnya 0.734; risk perception diukur denganmodifikasi Skala Risk Perception (Utami,2010)reliabilitasnya 0,888 sedangkan sensation seeking behaviour diukur dengan modifikasi Sensation Seeking Scale (SSS-V) dari Zuckerman (2007) reliabilitasnya 0.879.Teknik analisis data menggunakan regresi ganda. Nilai R2 yang diperoleh sebesar 0.324 and p<0.05. Hal ini berarti bahwa konformitas dan risk perception memiliki pengaruh terhadap sensation seeking behavior sebesar 32.4% (R2=0.324, p<0.05) sedangkan sisanya 67.6% dipengaruhi oleh faktor lain.
Penggunaan Metode Pembelajaran Peta Konsep (Mind Map) untuk Meningkatkan Hasil Belajar IPA Siswa Kelas VIII-B SMP Negeri 1 Ngimbang Semester I Tahun Pelajaran 2016-2017
Authors: Pujiati Wiwik
Published: April 2018

Permasalahan yang ingin dikaji dalam penelitian ini adalah apakah penggunaan media peta  konsep  dapat  meningkatkan  hasil  belajar  IPA  siswa  kelas  VIII-B  SMP  Negeri  1 Ngimbang semester I tahun pelajaran 2016-2017. Berdasarkan permasalahan tersebut, maka  tujuan  penelitian  tindakan  ini  adalah  untuk  mengetahui  apakah  penggunaan media peta konsep dapat meningkatkan hasil belajar IPA siswa kelas VIII-B SMP Negeri 1  Ngimbang  semester  I  tahun  pelajaran  2016-2017.  Sasaran  penelitian   ini  adalah semua  siswa  VIII  B  SMP  Negeri  1  Ngimbang  semester  I  tahun  pelajaran  2016-  2017 yang  berjumlah  34  siswa.  Penelitian  ini  menggunakan  penelitian  tindakan  (action research) sebanyak tiga siklus. Setiap siklus terdiri dari empat tahap yaitu: rancangan, kegiatan  dan  pengamatan,  refleksi,  dan  revisi.  Penelitian  ini  menghasilkan  simpulan bahwa  penggunaan  media  peta  konsep  dapat  meningkatkan  hasil  belajar  IPA  siswa  kelas VIII-B SMP Negeri 1 Ngimbang semester I tahun pelajaran  2016-2017.Keywords: Metode Peta Konsep (Mind Map)
Sistem Informasi Data Kriteria Rakyat Miskin Desa Liang Ilir Kecamatan Kota Bangun
Authors: Jainuddin Jainuddin , Agus Fahrul , Astuti Indah Fitri
Published: April 2018

Perkembangan Tingkat Kemiskinan di Kalimantan Timur, Pada Juli 2016 sampai Desember 2016 mengalami penurunan, jumlah penduduk miskin di Kalimantan Timur pada Desember 2016 sebesar 252,68 ribu (6,31 persen). Dibandingkan dengan penduduk miskin pada Juli 2016 sebesar 253,60 ribu orang (6,42 persen), berarti jumlah penduduk miskin berkurang sebanyak 0,92 ribu orang (0,11 persen). Penelitian ini bertujuan untuk membangun sistem manajemen data kriteria kemiskinan yang sumber datanya berasal dari pemerintah desa Liang Ilir dan Menghasilkan data keluarga miskin yang ideal dan tepat sasaran dalam membantu pemerintah daerah dalam program penanggulangan kemiskinan. Sistem ini dibuat dengan menggunakan conteks diagram, DFD desain dan database ERD. Sistem Informasi data Kriteria Rakyat miskin ini dirancang untuk melihat bagaimana sistem yang dibangun tersebut bekerja secara nyata, Implementasi rancangan perangkat lunak yang dibuat  menggunakan database MySQL sumber data bersumber dari instansi pemerintah yang mengeluarkan kriteria kemiskinan diantaranya data BPS, BKKBN, BKKBN, serta jurnal dalam acuan penelitian, Sistem informasi data kreteria rakyat miskin telah menghasilkan data keluarga miskin yang ideal dan tepat sasaran yang bisa menjadi acuan pemerintah Desa Liang Ilir Kecamatan Kota Bangun, dalam memetakan kondisi rakyat kurang mampu.