Rheological and Morphological Properties of Composites Based on Polylactide and Talc

Polylactide （PLA） is an emerging material mainly because it can be synthesized from renewable resources and is thus environmentally and ecologically safe. In this study, composites of PLA and talc were prepared by melt-blending technique, using a twin screw extruder. The influence of talc content on the rheological properties of pure PLA and its composites were evaluated. Dynamic rheological tests show that the incorporation of talc particles into PLA decreased system viscosity due to the filler＇s lubricant effect. However, as talc content increased, system＇s viscosity tended also to increase and materials with higher elastic behavior were produced, further with a higher plastic behavior in relation to pure PLA. This behavior can be observed by SEM micrographs.     

Synthesis of Nanocrystalline FeS2 with Increased Band Gap for Solar Energy Harvesting

In this paper,we have reported the synthesis of FeS2 of higher band gap energy（2.75 eV） by using capping reagent and its successive application in organic-inorganic based hybrid solar cells.Hydrothermal route was adopted for preparing iron pyrite（FeS2） nanoparticles with capping reagent PEG-400.The quality of synthesized FeS2 material was confirmed by X-ray diffraction,field emission scanning electron microscopy,transmission electron microscopy,Fourier transform infrared,thermogravimetric analyzer,and Raman study.The optical band gap energy and electro-chemical band gap energy of the synthesized FeS2 were investigated by UV-vis spectrophotometry and cyclic voltammetry.Finally band gap engineered FeS2 has been successfully used in conjunction with conjugated polymer MEHPPV for harvesting solar energy.The energy conversion efficiency was obtained as 0.064%with a fill-factor of 0.52.     

稀土铁酸盐的制备及光催化性能

在600℃温度下热分解配位前驱体,制备出5种稀土铁酸盐颗粒(ReFeO3,Re=Y3+、La3+、Sm3+、Gd3+和Ho3+).采用XRD、SEM、Uv-Vis DRS以及VSM等手段对所制备产物进行物相、表面形貌、能带结构以及磁性能等进行表征.XRD表明,含Y3+、La3+和Gd3+的前驱体灼烧后产物为单相正交晶系...     

Study of the Adsorption Space of Modified Clinoptilolites

Carbon dioxide （CO2） adsorption is an important adsorbent characterization method and a significant industrial process. In separation and recovery technology, the adsorption of the CO2 is important to reduce the concentration of this gas considered as one of the greenhouse gases. Natural zeolites, particularly clinoptilolite, are widely applied as adsorbents. In this regard, in the present research, the structure, composition and morphology of modified with hexafluorosilicate （HFSi） and orthophosphoric acid （H3PO4） clinoptilolites were investigated by characterizations and measurements made with, X-ray diffraction （XRD）, thermogravimetric analysis （TGA）, scanning electron microscopy-energy dispersive X-ray analysis （SEM-EDAX） and gravimetric adsorption. Additionally, the surface Chemistry of the modified clinoptilolites was analyzed by applying diffuse reflectance fourier transform infrared spectrometry （DRIFTS）. Further, the interaction of CO2 within the adsorption space of these modified clinoptilolites and a synthetic ZSM-5 zeolite was studied with the help of adsorption measurements. After all, an appropriate theoretical methodology for the analysis of the XRD and adsorption data was applied. The calculated cell parameters of the tested are similar to those reported for a typical clinoptilolite of： a = 17.662 A, b = 17.911A, c = 7.407 ~ and fl = 116.40 The resolution of the TGA derivative profiles indicated the presence of two steps for water release, one of them represents the loss of majority of the water present in the micropores. This was evidenced as a broad peak centered at about 50℃ for the CSW-HFSi-0.1, but at 100 ℃ for the samples CSW-HFSi-0.4. The SEM micrographs corresponding to the modified clinoptilolites, was evidenced that the CSW zeolite shows secondary particles exhibiting diameters from 3 to 40 μm, formed by primary clinoptilolite crystallites showing a crystallite size, φ = 40 nm. The EDAX elemental analysis it can be demonstrated that the exchange process replaced about 85% of the charge compensating ions. The DRIFT spectra of the modified clinoptilolites, specifically, CSW-HFSi-0.1, show a narrow band at about： 3,740 cm-1 corresponding to terminal silanol groups （Si-OH） and a band 3,600-3,650 cm1 resulting from extra-framework AI-OH. With the precision of the measured micropore volumes related to the excellent fitting of the adsorption data by the D-R isotherm equation, it can be affirm that carbon adsorption took only place in the micropore region. The isosteric heat of adsorption calculated for the modified clinoptilolites was greater than those values reported of ZSM-5 zeolite, particle packing silica, dealuminated Y zeolite （DAY） Cd, Zn and Ni-nitroprussides and Cu-nitroprusside and a Ni-MOF. With the obtained result it can be concluded that the modified clinoptilolites with HFSi showed a quality as adsorbent comparable to commercial synthetic zeolites.     

Management of the Quality of Corrosion Protection of Structural Steel Based on Corrosion Risk Level

The paper deals with the theoretical and practical aspects of improving regulatory and technical framework for assuring the quality and safety of metal structures and their protective coatings under the exposure of corrosive environment. Methodological approach has been developed to managing technological safety, assessing the risks of corrosion failures, and extension of an industrial facility＇s life based on company standards taking into account the requirements for safe operation of buildings and installations. Basic provisions of the method of limit states design have been analyzed to determine： design characteristics of corrosion impacts, computational models and design cases for affirming compliance of corrosion resistance, and durability and maintainability of structures and their protective coatings. Presented are practical examples of justifying the choice of means of primary and secondary protection, taking into account classification of the established levels of facility corrosion hazard. On the basis of limit state design principles, logistical control- and decision-making system is generated for reliability assurance of steel structures and protective coatings. Assessment criteria are specified for the risks with the use of the materials and technologies of primary and secondary corrosion protection.     

铜离子掺杂Y2Ba2O5高近红外反射颜料的制备和光学性能研究

采用溶胶-凝胶法制备一系列环境友好型绿色近红外反射纳米颜料, 结构通式为Y₂Ba_(2-x)Cu_xO₅(x=0、0.25、0.50、0.75和1.0), 通过X射线衍射(XRD)、扫描电子显微镜(SEM)、UV-vis-NIR分光光度仪和高精度分光测色仪对制备颜料的结构、形貌和光学性能进行了表征。研究结果表明, 铜离子掺杂进入Y₂Ba₂O₅晶格中, Y₂Ba₂O₅晶粒尺寸由62.1 nm降低至54.7 nm。Cu²⁺取代Y₂Ba₂O₅中的部分Ba²⁺, 粉末颜色由白色变为绿色(a*=-21.61), 禁带宽度由2.30 eV 减少到2.04 eV; 粉末呈现不规则球形结构, 粒径分布在150~300 nm范围内。掺杂Cu²⁺使粉末的近红外反射率降低, 但Cu²⁺掺杂量为x=0.50时仍然表现出较高的近红外反射率(68.80%)和太阳光反射率(45.95%)。因此, Y₂Ba_(2-x)Cu_xO₅系列高近红外反射绿色粉末作为“冷”颜料在建筑涂料方面具有巨大的应用潜能。     

Evaluation of Effects of C60 Fullerene and Its Derivatives on Selected Microorganisms

The contribution deals with preparation of C50 fullerene derivatives （oxo derivative, bromo derivative, hydrolyzed bromoderivative, bromo-chloro derivative）, their identification and pilot testing of their biological effects on unicellular organisms. The contribution describes effects of C60 fullerene derivatives, both on prokaryotic organisms （bacteria, cyanobacteria） and eukaryotic organisms （algae） and assesses their potential use as biocides.     

Removal of Arsenic from Waste Water by Using ZnO Nano-Materials

Zinc oxide has a unique position among semiconducting oxides due to its piezoelectric and transparent conducting properties. The catalyst-free synthesis of pure ZnO nanostructured material with 6-fold structural symmetry was synthesized by the chemical precipitation method. In this article, various nanostructures of ZnO which are grown by the chemical precipitation technique has been reported. Zinc oxide nanoparticles were synthesized by heating freshly prepared zinc hydroxide [Zn（OH）2] at 150℃ for two hours. The prepared compound was characterized by the X-Ray diffraction technique. Zinc oxide nanoparticles possess high removal capacity of As （III）, which can easily be separated and recycled during water treatment processes.     

Nostoc Linckia as Biosorbent of Chromium and Nickel from Electroplating Industry Wastewaters

The present study relates to the use of cyanobaeterium Nostoc linkia for removal of chromium and nickel from wastewater of galvanic industry. To determine concentrations of Cr and Ni in wastewater samples atomic absorption spectrometry was used. The samples of dried nostoc biomass after exposure to wastewater were subject to nondestructive instrumental neutron activation analysis. During 30 rain of the contact ofbiomass with wastewater 84% of chromium was removed from the wastewaters. Beside chromium after 30 rain nostoc biomass accumulates the amount of iron and zinc that exceeds their concentrations in the control biomass samples by a factor of 6 and 8, respectively. Nickel content in biomass after interaction with Cr-containing wastewater increases sixty fold and copper-sixteen fold. During the same time of biomass-Ni-containing wastewater interaction, 50% of nickel were accumulated. The method of Fourier transform infrared spectroscopy was applied to identify functional groups responsible for metal binding.     

Effects of Micro Silica on Permeability of Plastic Concrete

Water tightness and seepage control are important considerations in the design and construction of dams. Plastic concrete cut-off walls are one of the effective means for seepage control in earth dams constructed on permeable substrate. An important requirement for the plastic concrete in such applications is adequate strength for the design loads and low enough permeability to meet the water tightness requirements of the dam. As permeability of cement-based materials, such as concrete, is mainly dependent on water to cement ratio, the permeability of plastic concretes is much higher than those of normal concretes. It is thus apparent that the achieving to low permeability is an important problem in plastic concrete. So a method, which could reduce the permeability of plastic concretes without unduly increasing their elastic modulus, would provide considerable technical advantages. In the present research, the possibility of lowering the permeability of plastic concrete thorough replacement of a portion of cement by micro silica was investigated. The aim of the experimental research was to investigate the effects of various levels of cement replacement by micro silica, including 0%, 3%, 6%, 9%, 12% and 15% on strength and permeability of plastic concrete. The results illustrate that the use of micro silica for replacement of some of the cement content in plastic concrete results in very substantial decrease in permeability. Obtained results show that through the use of micro silica in plastic concrete, it is possible to keep the strength and elastic modulus at the level of control mix and still achieve to reduction in permeability.     

Light and Electron Microscopy Studies of the Visible Diffusion Zone of Mild Steel Pack Cyanided in Processed Cassava Leaves

This study investigates the microstructure of the processed cassava leaves. Standard parts machined from low visible diffusion zone formed in low carbon steel pack cyanided using carbon steel were pack cyanided by high temperature in-situ diffusion of nascent carbon and nitrogen into austenite. Formation of a visible diffusion zone was confirmed after observation with a Reichert-Jung Polyval optical microscope coupled with Zeiss AxioCam ICc 1 camera. High magnification Scanning Electron Microscope （SEM） imaging of the visible diffusion zone was done with a CamScan Series 2 scanning electron microscope. The zone was found variable in depth as measured from a representative position. The structure of all samples consists of ferrite and pearlite as determined by optical and SEM examination. Resulting products were thus both tough and hard suitable for service environments requiring high resistance to both wear and impact failure.     

Effect of Methyl Parathion on the Carbohydrate Metabolism of the Fish,Cirrhinus Mrigala

In general, any stress inducing substance will affect the respiratory metabolism of an animal. Any alteration in the intermediary metabolism due to stress is bound to affect the activity of oxidative enzymes like lactic dehydrogenase （LDH） and succinic dehydrogenase （SDH）. Both enzymes are involved in carbohydrate metabolism and have been used as an indicative criterion of exposure to chemical stress. Several authors have reported that the disturbance in the oxidative metabolism which leads to an alteration in whole oxygen consumption in different species of fishes exposed to pesticides. Carbohydrates are the primary and immediate source of energy. In stressed condition, the carbohydrate reserve （glycogen） is depleted to meet the energy demand. Depletion of glycogen may be due to the direct utilization for energy generation, a demand caused by the pesticide induced hypoxia. Similar findings have been reported in frog Rana tigrina. Glycogenolysis seems to be the result of increased secretion of catecholamines due to stress. Pesticides also inhibit energy production by suppressing aerobic oxidation of carbohydrates leading to energy crisis in animals. LDH and SDH are widely used in toxicology and clinical chemistry to diagnose the cell, tissue and organ damage. In the present study, the toxicological effect of methyl parathion on the LDH and SDH activity has been made in the fish, Cirrihinus mrigala. The study revealed that the acute toxicity （TUa） of methyl parathion was 14 ppm.     

Acid Activation of Kulantau Vermiculite

Adsorptive properties of laminated material with widening structural cell are determined by dispersion, which is depends on crystalline vermiculite grid structure. Created sorbents developed porous by acid activation desirable choice minerals with an expanding structural cell. Significant role in the formation of advanced sorbent porosity is the formation of thin layers of amorphous phase between partial destruction of the elements of the original structure of vermiculite.     

Surface Active Additives for Galvanic Coating of High Quality Obtainment

This article is devoted to research of surface active additive, acrylic reagent of the ＂Nakphlok＂ in the process of galvanic coating obtainment. It was proved that the copper coating obtained in the presence of electrolyte additives Nakphlok-C are of high quality.     

Design of Watertight Barriers for Retention Ponds of Cyanide Using Sludge from Water Purification Station （Ziga）

In a context of sustainable development and use of eco- materials, it was examined the possibility of using sewage sludge from the water treatment plant of Ziga as an inorganic support to achieve sealing barriers that can withstand high stresses to overcome any weaknesses of the geological barrier （called passive barrier）. The station Ziga that potabilises the water from the river Nakamb6 is located 45 km north east of Ouagadougou. Some experiments on the rheology of sludge from Ziga as well as the filtration of the mixture Ziga＇s sludge and clays from Nouna, Zorgho and Ticare, three regions of Burkina Faso, were conducted. These studies demonstrated the complex hydro-mechanical behavior of Ziga＇s slurries： Newtonian fluid thixotropic threshold for solids contents less than 16.5 wt% and non-Newtonian for higher values. Sludge from the water treatment station Ziga have a hydraulic conductivity of 10^-8 m/s. The results are below regulatory requirements. However, the permeability can be reduced to achieve the value of 10^-9 m/s in particular by adding the clay from Zorgho or Nouna to mixtures of Ziga＇s sludge and neutral leachate, typically mineral water. Beside neutral leachate, two types of leachate were used. One type is composed of acid leachate and the other type is basic. It was shown that the limewater solutions cause deterioration of the seal probably due to the presence of hydroxide ions.     

Experimental Study of Antispasmodic Activity of 2-Oksoindolin-3-Glyoxylic Acid Derivatives

Clinical psychiatry and neurology requires a creation of new means with difficult many component range of psychotropic action, so psychoemotional disturbances ＂boundary type＂ and difficult mental disorders have high level of heterogeneity, various clinical manifestations, which are caused by different pathogenetic factors. One of the most often used preparation for the treatment of these diseases is anxiolytic medications. It is known that anxiolytic action combines with anticonvulsive. Perspective medications are simple amides and ethers of 2-oksoindolin-3-glyoxylic acid, which have not recognized and practically observed. The aim of this research is to determine anticonvulsant action in 2-oksoindolin-3-glyoxylic acid derivatives on the model of acute myoclonic pentylentetrazol, piktrotoxic, and bikukullin convulsions. In experiments on mature mice of both sex Wistar line were studied an influence of ethyl ester 4-[2-hydroxy-2-（2-oxo-1,2-dihydro-indol-3-ylidene）-acetylamino]-butyric acid and 2-hydroxy-N-naphthalen-l-yl-2-（2-oxo-l,2-dihydro-indol-3-ylidene）-acetamide on chemoinduced epileptogenesis. An intake of proconvulsants is accompanied by a development of syndrome convulsion, which was estimated by convulsion＇s intensity （grades）, latent period of convulsions （sec.）, number of convulsions acts, and duration of convulsions （sec.） and number of survived animals in a group. It was showed that a combination of 2-hydroxy-N-naphthalen-1-yl-2-（2-oxo-1,2-dihydro-indol-3-ylidene）-acetamide （12 acetamide mg/kg） is similar to reference preparation diazepam in （2 mg/kg） which decreased a manifestation of syndrome convulsion. It demonstrated an increase of intensity of convulsions, decrease of latent period of the convulsion＇s start which is caused by all blockers GAMKA-receptors, decrease of number convulsive acts on the background of korazol and pikrotoxin, a decrease of convulsive syndrome duration during an intake ofkorazol and bikukullin, and a decrease of animal＇s mortalit     

Multi-Year Observation of Lung Cancer Metastases to the Spleen

The purpose of our study was to show if there is any correlation between the location of the primary cancer site in the lungs, and the appearance of metastases in the spleen. 1,998 patients with confirmed lung cancer were analyzed. In 22 out of 22 cases, splenic lesions were detected by both, computer tomography （CT） and ultrasound （US） in all 22 of them. All patients with splenic lesions detected by the US underwent US-guided biopsy. Among these patients, metastases to the spleen were histopathologically confirmed in all 22 cases. 18 metastases in the spleen originated from left lung tumors, 3 from right lung tumor. In the 1 case remaining, a pattern of benign lesion was confirmed. The authors came to the conclusion that lung cancer metastases detected in the spleen originate mainly from the left lung cancer which can be caused by higher blood flow to the left lung as compared to the right lung.     

Experimental Investigations of Hot Forging Die Surface Layer of Skd61 Steel in Die Sinking Electrical Discharge Machining

Electrical discharge machining is an important manufacturing process for tool mould and die industries. The results of the research about EDM show that the performance of die sink reduced due to a change in the material quality of the surface layer than the base material. The article presents the result of the study on the hot forging die surface layer of the SKD61 hot die steel （surface roughness, surface microscopic hardness, microscopic structure of the surface layer, EDS analysis of the surface layer） after die sinking electrical discharge machining using a tool of titanium and copper in oil dielectric.     

Composite Nanofibers Made of Polycaprolactone- Exoticwoods

The contribution describes preparation of the so-called ＂green composites＂ in which polycaprolactone serves as matrix and the reinforcement consists of nano- and micro-dust of selected exotic woods, i.e., teak, garapa and massaranduba. The composites were processed into nanofibers （by electrostatic spinning technology Nanospider） and their thermal stability was tested with regard to the type of wood. FTIR and SEM analyses were performed to determine structure and morphology of the surface, as well as strength characteristics.     

Fabrication of Bulk Targets of MgB2 with Stoichiometric and Nonstoichiometric Contents

Powder of magnesium diboride was obtained by solid phase reaction of mixture of magnesium （〉 99% pure） and amorphous boron （〉 99% pure） powders at 650-900 ℃ temperatures in inert atmosphere. During synthesis process main attention was paid. to removing oxide layer of surfaces of powder particles by organic solvents in Glovebox, where concentration of oxygen and water steam is less than 5 ppm. Homogenization and activation of powders were conducted in a planetary nano-mill by WC balls in an inert area. Pressing of the obtained powders was conducted in an argon atmosphere. MgB2 nonstoichiometric powders contained excess boron and magnesium, Magnesium hydride was used as source of excess boron, which is fragile compound and easy to grind in nano-mill. It decomposites with metallic magnesium and hydrogen up to 280 ℃ temperature. Commercial magnesium diboride powder （Aldrich, 〉 99%） was used for fabrication of MgB2 bulk targets. Powders systems of MgB2-Mg, MgB2-MgH2, MgB2-B homogenized by nano-mill in Glove box was used for fabrication of composites with nonstoichiometric contents. The targets were cylinders with diameters of 27-52 mm and height of 5-15 mm. Consolidation of pressed powdery composites was conducted in argon atmosphere. Synthesis of MgB2 from mixture of magnesium and amorphous boron powders and simultaneous consolidation were conducted by hot pressing （HP） method. Phase content of the obtained targets were established by XRD method after dry polishing. Superconducting characteristic of the obtained samples were measured by vibrational magnetometer. The superconducting transition with an onset at 39 K was observed in a good agreement with the results of the other groups obtained on samples prepared by conventional techniques. The phase exists near the nominal composition without a significant homogeneity range.