Direct and simultaneous detection of organic and inorganic ingredients in herbal powder preparations by Fourier transform infrared microspectroscopic imaging.

Science.gov (United States)

Chen, Jian-Bo; Sun, Su-Qin; Tang, Xu-Dong; Zhang, Jing-Zhao; Zhou, Qun

2016-08-05

Herbal powder preparation is a kind of widely-used herbal product in the form of powder mixture of herbal ingredients. Identification of herbal ingredients is the first and foremost step in assuring the quality, safety and efficacy of herbal powder preparations. In this research, Fourier transform infrared (FT-IR) microspectroscopic identification method is proposed for the direct and simultaneous recognition of multiple organic and inorganic ingredients in herbal powder preparations. First, the reference spectrum of characteristic particles of each herbal ingredient is assigned according to FT-IR results and other available information. Next, a statistical correlation threshold is determined as the lower limit of correlation coefficients between the reference spectrum and a larger number of calibration characteristic particles. After validation, the reference spectrum and correlation threshold can be used to identify herbal ingredient in mixture preparations. A herbal ingredient is supposed to be present if correlation coefficients between the reference spectrum and some sample particles are above the threshold. Using this method, all kinds of herbal materials in powder preparation Kouqiang Kuiyang San are identified successfully. This research shows the potential of FT-IR microspectroscopic identification method for the accurate and quick identification of ingredients in herbal powder preparations. Copyright © 2016 Elsevier B.V. All rights reserved.

In-line monitoring and optimization of powder flow in a simulated continuous process using transmission near infrared spectroscopy.

Science.gov (United States)

Alam, Md Anik; Shi, Zhenqi; Drennen, James K; Anderson, Carl A

2017-06-30

In-line monitoring of continuous powder flow is an integral part of the continuous manufacturing process of solid oral dosage forms in the pharmaceutical industry. Specifically, monitoring downstream from loss-in-weight (LIW) feeders and/or continuous mixers provides important data about the state of the process. Such measurements support control of the process and thereby enhance product quality. Near Infrared Spectroscopy (NIRS) is a potential PAT tool to monitor the homogeneity of a continuous powder flow stream in pharmaceutical manufacturing. However, the association of analytical results from NIR sampling of the powder stream and the homogeneity (content uniformity) of the resulting tablets provides several challenges; appropriate sampling strategies, adequately robust modeling techniques and poor sensitivities (for low dose APIs) are amongst them. Information from reflectance-based NIRS sampling is limited. The region of the powder bed that is interrogated is confined to the surface where the measurement is made. This potential bias in sampling may, in turn, limit the ability to predict the homogeneity of the finished dosage form. Further, changes to the processing parameters (e.g., rate of powder flow) often have a significant effect on the resulting data. Sample representation, interdependence between process parameters and their effects on powder flow behavior are critical factors for NIRS monitoring of continuous powder flow system. A transmission NIR method was developed as an alternative technique to monitor continuous powder flow and quantify API in the powder stream. Transmission NIRS was used to determine the thickness of the powder stream flowing from a loss-in-weight feeder. The thickness measurement of the powder stream provided an in-depth understanding about the effects of process parameters such as tube angles and powder flow rates on powder flow behaviors. This knowledge based approach helped to define an analytical design space that was

Design and fabrication of a real-time measurement system for the capsaicinoid content of Korean red pepper (Capsicum annuum L.) powder by visible and near-infrared spectroscopy

Science.gov (United States)

This research aims to design and fabricate a system to measure the capsaicinoid content of red pepper powder in a non-destructive and rapid method through visible and near infrared spectroscopy (VNIR). The developed system scans a well-leveled powder surface continuously to minimize the influence of...

Passivation process for superfine aluminum powders obtained by electrical explosion of wires

International Nuclear Information System (INIS)

Kwon, Young-Soon; Gromov, Alexander A.; Ilyin, Alexander P.; Rim, Geun-Hie

2003-01-01

The process of passivation of superfine aluminum powders (SFAPs) (a s ≤100 nm), obtained with the electrical explosion of wires (EEW) method, has been studied. The passivation coatings of different nature (oxides, stearic acid and aluminum diboride) were covered on the particle surface. The process of passivation and analysis of passivated powders was studied by X-ray photoelectron spectroscopy (XPS), XRD, TEM, infrared spectroscopy (IR), mass spectrometry (MS), thermocouple method and bomb calorimetry. After the comprehensive testing of coatings, a model of stabilization of the superfine aluminum particles was suggested, explaining the anomalous high content of aluminum metal in the electroexplosive powders. The main characteristic of the model is a formation of charged structures, which prevent metal oxidation

White light emission from Er2O3 nano-powder excited by infrared radiation

Science.gov (United States)

Tabanli, Sevcan; Eryurek, Gonul; Di Bartolo, Baldassare

2017-07-01

Phosphors of Er2O3 nano-crystalline powders were synthesized by the thermal decomposition method. The structural properties of the nano-powders were investigated with XRD and HRTEM measurements. The cubic phase with a = 10.540 Å was the only phase observed. The average crystalline sizes and the widths of the grain size distribution curves were determined to be 27.2, 18.7 and 9.7 nm, respectively. The spectroscopic properties of the Er2O3 nano-powder were studied by measuring the luminescence, decay and rise patterns under 808 and 975 nm diode laser excitations. A peculiar effect of the pressure was observed since an optically active ion (Er) is part of the complex and not a dopant. A broad band of the white light emission combined with blue, green and red up-conversion emission bands of Er3+ ions were observed at 0.03 mbar pressure under both excitation wavelengths. Only, an intense broad band white light emission was observed from these nanocrystals at atmospheric pressure. Rising patterns show that the white light intensity reaches its maximum value more rapidly under 975 nm excitation although it decays slower than that of 808 nm excitation. The color quality parameters such as the color coordinate (CRI), correlated color temperature and the color rendering index were found to vary with both the excitation wavelength and the ambient pressure indicating that these nanocrystals could be considered good white light emitting source under the infrared excitations.

Degradation assessment of natural weathering on low density polyethylene/thermoplastic soya spent powder blends

Science.gov (United States)

Nuradibah, M. A.; Sam, S. T.; Noriman, N. Z.; Ragunathan, S.; Ismail, H.

2015-07-01

Soya spent powder was blended with low density polyethylene (LDPE) ranging from 5-25 wt%. Glycerol was added to soya spent powder (SSP) for preparation of thermoplastic soya spent powder (TSSP). Then, the blends were exposed to natural weathering for 6 months. The susceptibility of the LDPE/soya spent powder blends based on its tensile, morphological properties and structural changes was measured every three months. The tensile strength of LDPE/TSSP blends after 6 months of weathering was the lowest compared to the other blends whereas LDPE/SSP blends after 6 months of weathering demonstrated the lowest elongation at break (Eb). Large pore can be seen on the surface of 25 wt% of LDPE/SSP blends.

[Study on Archaeological Lime Powders from Taosi and Yinxu Sites by FTIR].

Science.gov (United States)

Wei, Guo-feng; Zhang, Chen; Chen, Guo-liang; He, Yu-ling; Gao, Jiang-tao; Zhang, Bing-jian

2015-03-01

Archaeological lime powders samples from Taosi and Yinxu sites, natural limestone and experimentally prepared lime mortar were investigated by means of Fourier transform infrared spectrometry (FTIR) to identify the raw material of lime powders from Taosi and Yinxu sites. Results show that ν2/ν4 ratio of calcite resulted from carbonation reaction of man-made lime is around 6.31, which is higher than that of calcite in natural limestone and reflects the difference in the disorder of calcite crystal structure among the natural limestone and prepared lime mortar. With additional grinding, the values of v2 and ν4 in natural limestone and prepared lime mortar decrease. Meanwhile, the trend lines of ν2 versus ν4 for calcite in experimentally prepared lime mortar have a steeper slope when compared to calcite in natural limestone. These imply that ν2/ν4 ratio and the slope of the trend lines of ν2 versus ν4 can be used to determine the archaeological man-made lime. Based on the experiment results, it is possible that the archaeological lime powder from Taosi and Yinxu sites was prepared using man-made lime and the ancient Chinese have mastered the calcining technology of man-made lime in the late Neolithic period about 4 300 years ago.

[Studies on the brand traceability of milk powder based on NIR spectroscopy technology].

Science.gov (United States)

Guan, Xiao; Gu, Fang-Qing; Liu, Jing; Yang, Yong-Jian

2013-10-01

Brand traceability of several different kinds of milk powder was studied by combining near infrared spectroscopy diffuse reflectance mode with soft independent modeling of class analogy (SIMCA) in the present paper. The near infrared spectrum of 138 samples, including 54 Guangming milk powder samples, 43 Netherlands samples, and 33 Nestle samples and 8 Yili samples, were collected. After pretreatment of full spectrum data variables in training set, principal component analysis was performed, and the contribution rate of the cumulative variance of the first three principal components was about 99.07%. Milk powder principal component regression model based on SIMCA was established, and used to classify the milk powder samples in prediction sets. The results showed that the recognition rate of Guangming milk powder, Netherlands milk powder and Nestle milk powder was 78%, 75% and 100%, the rejection rate was 100%, 87%, and 88%, respectively. Therefore, the near infrared spectroscopy combined with SIMCA model can classify milk powder with high accuracy, and is a promising identification method of milk powder variety.

Polarised infrared cathodoluminescence from platelet defects in natural diamonds

International Nuclear Information System (INIS)

Kiflawi, I.; Lang, A.R.

1977-01-01

It is reported that the large platelet defects occasionally found in natural diamonds emit polarised cathodoluminescence in the near infrared. There is much uncertainty regarding the composition and structure of the platelets. New findings on the optical properties of the platelets are discussed. The discovery that cathodoluminescence from giant platelets can be seen in the near infrared using an image converter was followed up by photographic recording with Kodak high speed infrared films, and it was found that the infrared emission from the platelets is polarised in the platelet plane with a considerably higher polarisation ratio than in the case of their visible emissions. In order to assess the degree of polarisation of the infrared emission a Polaroid Type HR linear polariser was used, which is very effective at the longest wavelengths recorded by the Kodak high speed infrared film. The high degree of polarisation of the platelet infrared emission constitutes a well defined optical characteristic that any model for platelet structure, and for optical processes associated with platelets, must satisfactorily accommodate. (U.K.)

Preparation of tris(8-hydroxyquinolinato)aluminum thin films by sputtering deposition using powder and pressed powder targets

Science.gov (United States)

Kawasaki, Hiroharu; Ohshima, Tamiko; Yagyu, Yoshihito; Ihara, Takeshi; Tanaka, Rei; Suda, Yoshiaki

2017-06-01

Tris(8-hydroxyquinolinato)aluminum (Alq3) thin films, for use in organic electroluminescence displays, were prepared by a sputtering deposition method using powder and pressed powder targets. Experimental results suggest that Alq3 thin films can be prepared using powder and pressed powder targets, although the films were amorphous. The surface color of the target after deposition became dark brown, and the Fourier transform infrared spectroscopy spectrum changed when using a pressed powder target. The deposition rate of the film using a powder target was higher than that using a pressed powder target. That may be because the electron and ion densities of the plasma generated using the powder target are higher than those when using pressed powder targets under the same deposition conditions. The properties of a thin film prepared using a powder target were almost the same as those of a film prepared using a pressed powder target.

Chemical and structural characterization of natural phosphate of ...

African Journals Online (AJOL)

Powder X-ray diffraction fitting results confirm that compound belongs to the apatite family crystallising in the hexagonal system, space group P63/m. The cell parameters are: a = 9.3547(5) Å; c = 6.8929(4) Å. KEY WORDS: Natural phosphate, Fluoroapatite, Infrared, X-Ray diffraction, Rietveld structure refinement. Bull. Chem ...

Preparation of fine powdered composite for latent heat storage

Energy Technology Data Exchange (ETDEWEB)

Fořt, Jan, E-mail: jan.fort.1@fsv.cvut.cz; Trník, Anton, E-mail: anton.trnik@fsv.cvut.cz; Pavlíková, Milena, E-mail: milena.pavlikova@fsv.cvut.cz; Pavlík, Zbyšek, E-mail: pavlikz@fsv.cvut.cz [Department of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, Thákurova 7, 166 29 Prague (Czech Republic); Pomaleski, Marina, E-mail: marina-pomaleski@fsv.cvut.cz [Faculty of Civil Engineering, Architecture and Urbanism, University of Campinas, R. Saturnino de Brito 224, 13083-889 Campinas – SP (Brazil)

2016-07-07

Application of latent heat storage building envelope systems using phase-change materials represents an attractive method of storing thermal energy and has the advantages of high-energy storage density and the isothermal nature of the storage process. This study deals with a preparation of a new type of powdered phase change composite material for thermal energy storage. The idea of a composite is based upon the impregnation of a natural silicate material by a reasonably priced commercially produced pure phase change material and forming the homogenous composite powdered structure. For the preparation of the composite, vacuum impregnation method is used. The particle size distribution accessed by the laser diffraction apparatus proves that incorporation of the organic phase change material into the structure of inorganic siliceous pozzolana does not lead to the clustering of the particles. The compatibility of the prepared composite is characterized by the Fourier transformation infrared analysis (FTIR). Performed DSC analysis shows potential of the developed composite for thermal energy storage that can be easily incorporated into the cement-based matrix of building materials. Based on the obtained results, application of the developed phase change composite can be considered with a great promise.

Temperature evolution during compaction of pharmaceutical powders.

Science.gov (United States)

Zavaliangos, Antonios; Galen, Steve; Cunningham, John; Winstead, Denita

2008-08-01

A numerical approach to the prediction of temperature evolution in tablet compaction is presented here. It is based on a coupled thermomechanical finite element analysis and a calibrated Drucker-Prager Cap model. This approach is capable of predicting transient temperatures during compaction, which cannot be assessed by experimental techniques due to inherent test limitations. Model predictions are validated with infrared (IR) temperature measurements of the top tablet surface after ejection and match well with experiments. The dependence of temperature fields on speed and degree of compaction are naturally captured. The estimated transient temperatures are maximum at the end of compaction at the center of the tablet and close to the die wall next to the powder/die interface.

Application of gamma irradiation for incorporation of rubber powder in the formulations of EPDM and natural rubber

International Nuclear Information System (INIS)

Kiyan, Ludmila Y.P.; Parra, Duclerc Fernandes; Lugao, Ademar Benevolo

2013-01-01

The objective of this work was to study the behavior of the recycling of rubber burrs in form of powder, of the rubber industry from EPDM rubber powder and natural rubber with SBR. The rubber powder was irradiated and reused in rubber artifacts formulations for classical vulcanization. The processed material was irradiated using a 60 Co source in doses of 50, 100, 150 and 200 kGy and a dose rate of 5 kGy s-1 at room temperature. The radiation created devulcanization active sites for subsequent integration of the material (rubber powder) in formulations of commercial use. The processes were compared and their products characterized by analytical methods of the physical properties such as strength and elongation. Satisfactory results were found, noting a major spin-off of EPDM chain demonstrated by increased elongation

Determination of carbon content of UO2, (U, Gd)O2 and (U, Pu)O2 powders and sintered pellets - Combustion in a high-frequency induction furnace -Infrared absorption spectrometry

International Nuclear Information System (INIS)

2008-01-01

This International Standard describes a method for determining the carbon content in UO 2 , (U,Gd)O 2 and (U,Pu)O 2 powder and sintered pellets by combustion in an induction furnace and infrared absorption spectroscopy measurement. It is applicable for determining 10 μg/g to 500 μg/g of carbon in UO 2 , (U,Gd)O 2 and (U,Pu)O 2 powder and pellets. The sample is heated to a temperature above 1500 deg. C in an induction furnace, under pure oxygen atmosphere, to convert any carbon compounds to carbon dioxide gas. The resulting carbon dioxide gas is filtered and dried before measurement using infrared spectroscopy to measure the carbon dioxide signal at 2350 cm -1 . The result is converted into the carbon content of the material analysed

Quantitative analysis of mineral powders by DRIFTS: Determination of SrCO3 in superconductor precursor powders

DEFF Research Database (Denmark)

Bak, J.; Kindl, B.

1997-01-01

An application of diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) has been demonstrated to be able to determine small concentrations, down to the 100-ppm level, of carbonates in powdery superconductor (SPC) precursor samples, The detection of carbonates in SPC precursor powders...

Green biosynthesis of silver nanoparticles using Curcuma longa tuber powder

Science.gov (United States)

Shameli, Kamyar; Ahmad, Mansor Bin; Zamanian, Ali; Sangpour, Parvanh; Shabanzadeh, Parvaneh; Abdollahi, Yadollah; Zargar, Mohsen

2012-01-01

Green synthesis of noble metal nanoparticles is a vastly developing area of research. Metallic nanoparticles have received great attention from chemists, physicists, biologists, and engineers who wish to use them for the development of a new-generation of nanodevices. In this study, silver nanoparticles were biosynthesized from aqueous silver nitrate through a simple and eco-friendly route using Curcuma longa tuber-powder extracts, which acted as a reductant and stabilizer simultaneously. Characterizations of nanoparticles were done using different methods, which included ultraviolet-visible spectroscopy, powder X-ray diffraction, transmission electron microscopy, scanning electron microscopy, energy-dispersive X-ray fluorescence spectrometry, and Fourier-transform infrared spectroscopy. The ultraviolet-visible spectrum of the aqueous medium containing silver nanoparticles showed an absorption peak at around 415 nm. Transmission electron microscopy showed that mean diameter and standard deviation for the formation of silver nanoparticles was 6.30 ± 2.64 nm. Powder X-ray diffraction showed that the particles are crystalline in nature, with a face-centered cubic structure. The most needed outcome of this work will be the development of value-added products from C. longa for biomedical and nanotechnology-based industries. PMID:23341739

Operation whey powder

International Nuclear Information System (INIS)

Brunner, E.

1987-01-01

The odyssey of the contaminated whey powder finally has come to an end, and the 5000 tonnes of whey now are designated for decontamination by means of an ion exchange technique. The article throws light upon the political and economic reasons that sent the whey powder off on a chaotic journey. It is worth mentioning in this context that the natural radioactivity of inorganic fertilizers is much higher than that of the whey powder in question. (HP) [de

The effect of polymorphism on powder compaction and dissolution properties of chemically equivalent oxytetracycline hydrochloride powders.

Science.gov (United States)

Liebenberg, W; de Villiers, M M; Wurster, D E; Swanepoel, E; Dekker, T G; Lötter, A P

1999-09-01

In South Africa, oxytetracycline is identified as an essential drug; many generic products are on the market, and many more are being developed. In this study, six oxytetracycline hydrochloride powders were obtained randomly from manufacturers, and suppliers were compared. It was found that compliance to a pharmacopoeial monograph was insufficient to ensure the optimum dissolution performance of a simple tablet formulation. Comparative physicochemical raw material analysis showed no major differences with regard to differential scanning calorimetry (DSC), infrared (IR) spectroscopy, powder dissolution, and particle size. However, the samples could be divided into two distinct types with respect to X-ray powder diffraction (XRD) and thus polymorphism. The two polymorphic forms had different dissolution properties in water or 0.1 N hydrochloride acid. This difference became substantial when the dissolution from tablets was compared. The powders containing form A were less soluble than that containing form B.

Growing three-dimensional biomorphic graphene powders using naturally abundant diatomite templates towards high solution processability

Science.gov (United States)

Chen, Ke; Li, Cong; Shi, Liurong; Gao, Teng; Song, Xiuju; Bachmatiuk, Alicja; Zou, Zhiyu; Deng, Bing; Ji, Qingqing; Ma, Donglin; Peng, Hailin; Du, Zuliang; Rümmeli, Mark Hermann; Zhang, Yanfeng; Liu, Zhongfan

2016-11-01

Mass production of high-quality graphene with low cost is the footstone for its widespread practical applications. We present herein a self-limited growth approach for producing graphene powders by a small-methane-flow chemical vapour deposition process on naturally abundant and industrially widely used diatomite (biosilica) substrates. Distinct from the chemically exfoliated graphene, thus-produced biomorphic graphene is highly crystallized with atomic layer-thickness controllability, structural designability and less noncarbon impurities. In particular, the individual graphene microarchitectures preserve a three-dimensional naturally curved surface morphology of original diatom frustules, effectively overcoming the interlayer stacking and hence giving excellent dispersion performance in fabricating solution-processible electrodes. The graphene films derived from as-made graphene powders, compatible with either rod-coating, or inkjet and roll-to-roll printing techniques, exhibit much higher electrical conductivity (~110,700 S m-1 at 80% transmittance) than previously reported solution-based counterparts. This work thus puts forward a practical route for low-cost mass production of various powdery two-dimensional materials.

A comparative study of the use of powder X-ray diffraction, Raman and near infrared spectroscopy for quantification of binary polymorphic mixtures of piracetam.

Science.gov (United States)

Croker, Denise M; Hennigan, Michelle C; Maher, Anthony; Hu, Yun; Ryder, Alan G; Hodnett, Benjamin K

2012-04-07

Diffraction and spectroscopic methods were evaluated for quantitative analysis of binary powder mixtures of FII(6.403) and FIII(6.525) piracetam. The two polymorphs of piracetam could be distinguished using powder X-ray diffraction (PXRD), Raman and near-infrared (NIR) spectroscopy. The results demonstrated that Raman and NIR spectroscopy are most suitable for quantitative analysis of this polymorphic mixture. When the spectra are treated with the combination of multiplicative scatter correction (MSC) and second derivative data pretreatments, the partial least squared (PLS) regression model gave a root mean square error of calibration (RMSEC) of 0.94 and 0.99%, respectively. FIII(6.525) demonstrated some preferred orientation in PXRD analysis, making PXRD the least preferred method of quantification. Copyright © 2012 Elsevier B.V. All rights reserved.

Effect of fabrication conditions on the properties of indium tin oxide powders

International Nuclear Information System (INIS)

Xie Wei

2008-01-01

This paper reports that indium tin oxide (ITO) crystalline powders are prepared by coprecipitation method. Fabrication conditions mainly as sintering temperature and Sn doping content are correlated with the phase, microstructure, infrared emissivity in and powder resistivity of indium tin oxides by means of x-ray diffraction, Fourier transform infrared, and transmission electron microscope. The optimum sintering temperature of 1350°C and Sn doping content 6∼8wt% are determined. The application of ITO in the military camouflage field is proposed. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

Study on the infrared radiation performance of Tourmaline composite and its effect on the diesel characteristic

Science.gov (United States)

Liao, Jian Bin; Yu, Hong Liang; Sun, Di; Ma, Fong Yuan

2017-09-01

The black tourmaline, magnesium tourmaline, and spinel were ground into powder, and the infrared radiation material was prepared by adding the ceramic powder, clay and the other material into the tourmaline powder according to a certain proportion. The infrared radiation property was tested and analyzed, the diesel was infrared radiation activated by the composite material, and the physicochemical property of fuel oil was analyzed pre-test and post-test. The result shows that the infrared absorption spectrum of the black tourmaline of different particle size is stable. After the diesel oil was infrared radiation activated by tourmaline composite materials, the physicochemical property of diesel oil was changed, the activation energy decreased, the viscosity and surface tension of fuel oil were reduced.

Growing three-dimensional biomorphic graphene powders using naturally abundant diatomite templates towards high solution processability.

Science.gov (United States)

Chen, Ke; Li, Cong; Shi, Liurong; Gao, Teng; Song, Xiuju; Bachmatiuk, Alicja; Zou, Zhiyu; Deng, Bing; Ji, Qingqing; Ma, Donglin; Peng, Hailin; Du, Zuliang; Rümmeli, Mark Hermann; Zhang, Yanfeng; Liu, Zhongfan

2016-11-07

Mass production of high-quality graphene with low cost is the footstone for its widespread practical applications. We present herein a self-limited growth approach for producing graphene powders by a small-methane-flow chemical vapour deposition process on naturally abundant and industrially widely used diatomite (biosilica) substrates. Distinct from the chemically exfoliated graphene, thus-produced biomorphic graphene is highly crystallized with atomic layer-thickness controllability, structural designability and less noncarbon impurities. In particular, the individual graphene microarchitectures preserve a three-dimensional naturally curved surface morphology of original diatom frustules, effectively overcoming the interlayer stacking and hence giving excellent dispersion performance in fabricating solution-processible electrodes. The graphene films derived from as-made graphene powders, compatible with either rod-coating, or inkjet and roll-to-roll printing techniques, exhibit much higher electrical conductivity (∼110,700 S m -1 at 80% transmittance) than previously reported solution-based counterparts. This work thus puts forward a practical route for low-cost mass production of various powdery two-dimensional materials.

Yttrium orthoferrite powder obtained by the mechanochemical synthesis

Directory of Open Access Journals (Sweden)

Lazarević Zorica Ž.

2017-01-01

Full Text Available Yttrium orthoferrite (YFeO3 powder was prepared by a mechanochemical synthesis from a mixture of Y2O3 and α-Fe2O3 powders in a planetary ball mill for 2.5 h. The obtained YFeO3 powder sample was characterized by X-ray diffraction (XRD, Raman and infrared spectroscopy. The average crystallite size calculated by the Scherrer equation was 12 nm. The Mössbauer spectroscopy at room temperature confirms the superparamagnetic character of YFeO3 orthoferrite sample. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III 45003, Grant no. III 45015, Grant no. III 45018

Design and Fabrication of a Real-Time Measurement System for the Capsaicinoid Content of Korean Red Pepper (Capsicum annuum L.) Powder by Visible and Near-Infrared Spectroscopy.

Science.gov (United States)

Lim, Jongguk; Kim, Giyoung; Mo, Changyeun; Kim, Moon S

2015-10-29

This research aims to design and fabricate a system to measure the capsaicinoid content of red pepper powder in a non-destructive and rapid method using visible and near infrared spectroscopy (VNIR). The developed system scans a well-leveled powder surface continuously to minimize the influence of the placenta distribution, thus acquiring stable and representative reflectance spectra. The system incorporates flat belts driven by a sample input hopper and stepping motor, a powder surface leveler, charge-coupled device (CCD) image sensor-embedded VNIR spectrometer, fiber optic probe, and tungsten halogen lamp, and an automated reference measuring unit with a reference panel to measure the standard spectrum. The operation program includes device interface, standard reflectivity measurement, and a graphical user interface to measure the capsaicinoid content. A partial least square regression (PLSR) model was developed to predict the capsaicinoid content; 44 red pepper powder samples whose measured capsaicinoid content ranged 13.45-159.48 mg/100 g by per high-performance liquid chromatography (HPLC) and 1242 VNIR absorbance spectra acquired by the pungency measurement system were used. The determination coefficient of validation (RV2) and standard error of prediction (SEP) for the model with the first-order derivative pretreatment method for Korean red pepper powder were 0.8484 and ±13.6388 mg/100 g, respectively.

Powder preparation technics for SnO2 with submycrometrics particles

International Nuclear Information System (INIS)

Hiratsuka, R.S.; Pulcinelli, S.H.; Santilli, C.V.; Masetto, S.R.

1989-01-01

Preparation of SnO 2 fine powders is a pointer research because of this application as gas detecting sensors. This work shows basicaly two powder preparation methods: i) from metalic tin oxidation with nitric acid, ii) from SnCl 4 hydrolysis in aquous solution of amonia hydroxides. It was analysed the concentration of nitric acid and the pH of precipitation influency of the structural and morphologic characteristics of the obtained powders. The materials were characterized by X-ray diffraction, infra-red spectroscopy and specific surface area [pt

Sliding friction and wear behaviors of surface-coated natural serpentine mineral powders as lubricant additive

International Nuclear Information System (INIS)

Zhang Baosen; Xu Yi; Gao Fei; Shi Peijing; Xu Binshi; Wu Yixiong

2011-01-01

This work aims to investigate the friction and wear properties of surface-coated natural serpentine powders (SP) suspended in diesel engine oil using an Optimal SRV oscillating friction and wear tester. The worn surface was characterized by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS). Results indicated that the additives can improve the wear resistance and decrease friction coefficient of carbon steel friction couples. The 0.5 wt% content of serpentine powders is found most efficient in reducing friction and wear at the load of 50 N. The SEM and XPS analysis results demonstrate that a tribofilm forms on the worn surface, which is responsible for the decrease in friction and wear, mainly with iron oxides, silicon oxides, graphite and organic compounds.

Some critical aspects of FT-IR, TGA, powder XRD, EDAX and SEM studies of calcium oxalate urinary calculi.

Science.gov (United States)

Joshi, Vimal S; Vasant, Sonal R; Bhatt, J G; Joshi, Mihir J

2014-06-01

Urinary calculi constitute one of the oldest afflictions of humans as well as animals, which are occurring globally. The calculi vary in shape, size and composition, which influence their clinical course. They are usually of the mixed-type with varying percentages of the ingredients. In medical management of urinary calculi, either the nature of calculi is to be known or the exact composition of calculi is required. In the present study, two selected calculi were recovered after surgery from two different patients for detailed examination and investigated by using Fourier-Transform infrared spectroscopy (FT-IR), thermo-gravimetric analysis (TGA), powder X-ray diffraction (XRD), scanning electron microscopy and energy dispersive analysis of X-rays (EDAX) techniques. The study demonstrated that the nature of urinary calculi and presence of major phase in mixed calculi could be identified by FT-IR, TGA and powder XRD, however, the exact content of various elements could be found by EDAX only.

Design and Fabrication of a Real-Time Measurement System for the Capsaicinoid Content of Korean Red Pepper (Capsicum annuum L. Powder by Visible and Near-Infrared Spectroscopy

Directory of Open Access Journals (Sweden)

Jongguk Lim

2015-10-01

Full Text Available This research aims to design and fabricate a system to measure the capsaicinoid content of red pepper powder in a non-destructive and rapid method using visible and near infrared spectroscopy (VNIR. The developed system scans a well-leveled powder surface continuously to minimize the influence of the placenta distribution, thus acquiring stable and representative reflectance spectra. The system incorporates flat belts driven by a sample input hopper and stepping motor, a powder surface leveler, charge-coupled device (CCD image sensor-embedded VNIR spectrometer, fiber optic probe, and tungsten halogen lamp, and an automated reference measuring unit with a reference panel to measure the standard spectrum. The operation program includes device interface, standard reflectivity measurement, and a graphical user interface to measure the capsaicinoid content. A partial least square regression (PLSR model was developed to predict the capsaicinoid content; 44 red pepper powder samples whose measured capsaicinoid content ranged 13.45–159.48 mg/100 g by per high-performance liquid chromatography (HPLC and 1242 VNIR absorbance spectra acquired by the pungency measurement system were used. The determination coefficient of validation (RV2 and standard error of prediction (SEP for the model with the first-order derivative pretreatment method for Korean red pepper powder were 0.8484 and ±13.6388 mg/100 g, respectively.

Dyeing of γ-irradiated cotton with natural flavonoid dye extracted from irradiated onion shells (Allium cepa) powder

Science.gov (United States)

Rehman, Fazal-ur; Adeel, Shahid; Shahid, Muhammad; Bhatti, Ijaz Ahmad; Nasir, Faiza; Akhtar, Nasim; Ahmad, Zulfiqar

2013-11-01

Powder of Onion shells as a source of natural flavonoid dye (Quercetin) and cotton fabrics were exposed to absorbed doses of 2, 4, 6, 8 and 10 kGy using Cs-137 gamma irradiator. Irradiated and un-irradiated dye powder was used for extraction of quercetin as well as antibacterial, hemolytic and antioxidant activities were also determined to observe the effect of radiation. Furthermore, color strength and colourfastness of irradiated fabrics were improved by using pre and post-mordants such as alum and iron. It is found that 4 kGy is the optimal absorbed dose for extraction of natural quercetin extracted from onion shells while maximum color strength and acceptable fastness properties are obtained on dyeing of irradiated fabric at 60 °C keeping M:L of 1:30 using 10% alum as pre-mordant and 6% alum as post-mordant. Gamma irradiation has not only improved the color strength of the dye using irradiated cotton but also that of colourfastness properties.

One-Step Hydrothermal-Electrochemical Route to Carbon-Stabilized Anatase Powders

Science.gov (United States)

Tao, Ying; Yi, Danqing; Zhu, Baojun

2013-04-01

Black carbon-stabilized anatase particles were prepared by a simple one-step hydrothermal-electrochemical method using glucose and titanium citrate as the carbon and titanium source, respectively. Morphological, chemical, structural, and electrochemical characterizations of these powders were carried out by Raman spectroscopy, Fourier-transform infrared spectroscopy, x-ray diffraction, scanning electron microscopy, and cyclic voltammetry. It was revealed that 200-nm carbon/anatase TiO2 was homogeneously dispersed, and the powders exhibited excellent cyclic performance at high current rates of 0.05 V/s. The powders are interesting potential materials that could be used as anodes for lithium-ion batteries.

Nanostructured hydroxyapatite powders produced by a flame-based technique

Energy Technology Data Exchange (ETDEWEB)

Trommer, R.M., E-mail: rafael_trommer@yahoo.com.br [Ceramic Materials Laboratory, av. Osvaldo Aranha 99/705, 90035190, Porto Alegre, RS (Brazil); Santos, L.A. [Biomaterials Laboratory, av. Bento Goncalves 9500, Campus do Vale Setor IV Predio 74 Sala 123, 91501970, Porto Alegre, RS (Brazil); Bergmann, C.P. [Ceramic Materials Laboratory, av. Osvaldo Aranha 99/705, 90035190, Porto Alegre, RS (Brazil)

2009-08-01

In this work we reported the production of hydroxyapatite (HA) powder, one of the most studied calcium phosphates in the bioceramics field, using a cost-effective apparatus, composed by three major components: the atomization device, the pilot and main flames and finally the powder collector system. Calcium acetate and ammonium phosphate, diluted in ethanol and water, were used as salts in the precursor solution. The Ca/P molar ratio in the precursor solution was 1.65, equivalent to biological hydroxyapatite. After its production and collection, HA powder was calcined at 600 deg. C for 2 h. X-ray diffraction analysis pointed to the formation of crystalline hydroxyapatite powders. Carbonate was identified in the powders by Fourier-transform infrared (FTIR) spectroscopy. Scanning electronic microscopy (SEM) showed that the powders were composed of spherical primary particles and secondary aggregates, with the morphology unchanged after calcination. By transmission electronic microscopy (TEM), it was observed that the crystallite size of the primary particles was 24.8 {+-} 5.8 nm, for the calcined powder. The specific surface area was 15.03 {+-} 6.4 and 26.50 {+-} 7.6 m{sup 2}/g, for the as-synthetized and calcined powder respectively.

Influence of short chain organic acids and bases on the wetting properties and surface energy of submicrometer ceramic powders.

Science.gov (United States)

Neirinck, Bram; Soccol, Dimitri; Fransaer, Jan; Van der Biest, Omer; Vleugels, Jef

2010-08-15

The effect of short chained organic acids and bases on the surface energy and wetting properties of submicrometer alumina powder was assessed. The surface chemistry of treated powders was determined by means of Diffuse Reflectance Infrared Fourier Transform spectroscopy and compared to untreated powder. The wetting of powders was measured using a modified Washburn method, based on the use of precompacted powder samples. The geometric factor needed to calculate the contact angle was derived from measurements of the porous properties of the powder compacts. Contact angle measurements with several probe liquids before and after modification allowed a theoretical estimation of the surface energy based on the surface tension component theory. Trends in the surface energy components were linked to observations in infrared spectra. The results showed that the hydrophobic character of the precompacted powder depends on both the chain length and polar group of the modifying agent. Copyright 2010 Elsevier Inc. All rights reserved.

The pressure bonding ability of uranium dioxide powders in relation to the evolution of their surface properties

International Nuclear Information System (INIS)

Danroc, J.

1982-09-01

The long term storage of sinterable uranium dioxide powders generally improves their pressure bonding ability and the strength of the resulting green pellets. Evidence of the gradual evolution of the surface texture and composition of these powders during storage at room temperature and pressure has been provided by infrared spectroscopy, X-ray diffraction and thermogravimetric and microcalorimetric methods. These techniques demonstrated the existence of a thin adherent surface layer of UO 3 2H 2 0. Such a natural evolutionary process can be reproduced and substantially amplified by subjecting the powder to thermal treatments at temperatures up to 90 0 C in a moist air environment. It was shown that powder treated in this manner could be more readily compacted into strong green pellets than could raw material. The tensile strength, commonly regarded as a quality test for such pellets and measured by the brazilian method, was found to be at least twice that of normal pellets. The high density and geometric integrity of these sintered products ensures the extrapolation of these preparation techniques to the mass production of nuclear reactor fuel pellets [fr

Development of a differential infrared absorption method to measure the deuterium content of natural water

International Nuclear Information System (INIS)

D'Alessio, Enrique; Bonadeo, Hernan; Karaianev de Del Carril, Stiliana.

1975-07-01

A system to measure the deuterium content of natural water using differential infrared spectroscopy is described. Parameters conducing to an optimized design are analyzed, and the construction of the system is described. A Perkin Elmer 225 infrared spectrometer, to which a scale expansion system has been added, is used. Sample and reference waters are alternatively introduced by a pneumatical-mechanical system into a unique F Ca thermostatized infrared cell. Results and calibration curves shown prove that the system is capable of measuring deuterium content with a precision of 1 part per million. (author)

Synthesis of ultrafine alumina powders using egg white as complexing medium

International Nuclear Information System (INIS)

Salem, R.E.P.; Guilherme, K. A.; Chinelatto, A.S.A.; Chinelatto, A.L.

2011-01-01

Synthesis of alumina powders through chemical methods has been attracting much attention of researchers in the past few years, due to the ability to produce powders in nanometric scale with high degree of purity. In this work, there were synthesized alumina powders through a chemical route, using egg white as a complexing medium and aluminium nitrate as the source of Al 3+ cations. Egg white contains ovalbumin, a protein which acts effectively on the isolation of aluminium cations during the mixing process, enabling the formation of ultrafine alumina powders in a relatively economic and environmentally friendly way. The powders obtained by calcinations of the precursor resin were characterized by X-ray diffraction, specific surface area measurements, infrared spectroscopy and scanning electron microscopy. It was observed that the egg white, present at the reaction medium, allowed obtaining transition alumina powders, with high degree of purity. (author)

Dyeing of γ-irradiated cotton with natural flavonoid dye extracted from irradiated onion shells (Allium cepa) powder

International Nuclear Information System (INIS)

Rehman, Fazal-ur; Adeel, Shahid; Shahid, Muhammad; Bhatti, Ijaz Ahmad; Nasir, Faiza; Akhtar, Nasim; Ahmad, Zulfiqar

2013-01-01

Powder of Onion shells as a source of natural flavonoid dye (Quercetin) and cotton fabrics were exposed to absorbed doses of 2, 4, 6, 8 and 10 kGy using Cs-137 gamma irradiator. Irradiated and un-irradiated dye powder was used for extraction of quercetin as well as antibacterial, hemolytic and antioxidant activities were also determined to observe the effect of radiation. Furthermore, color strength and colourfastness of irradiated fabrics were improved by using pre and post-mordants such as alum and iron. It is found that 4 kGy is the optimal absorbed dose for extraction of natural quercetin extracted from onion shells while maximum color strength and acceptable fastness properties are obtained on dyeing of irradiated fabric at 60 °C keeping M:L of 1:30 using 10% alum as pre-mordant and 6% alum as post-mordant. Gamma irradiation has not only improved the color strength of the dye using irradiated cotton but also that of colourfastness properties. - Highlights: • The optimal absorbed dose obtained for surface modification of cotton (RC) is 4 kGy. • The optimal absorbed dose for extraction of colorant from onion shell powder (RP) is 4 kGy. • Optimum dying conditions: 60 °C, 1 30 as M:L. • Optimum pre-mordant 10% alum and 6% alum as post-mordant. • At these optimum conditions: color strength and fastness properties are improved

High-Yield Preparation and Electrochemical Properties of Few-Layer MoS2 Nanosheets by Exfoliating Natural Molybdenite Powders Directly via a Coupled Ultrasonication-Milling Process

Science.gov (United States)

Dong, Huina; Chen, Deliang; Wang, Kai; Zhang, Rui

2016-09-01

Cost-effective and scalable preparation of two-dimensional (2D) molybdenum disulfide (MoS2) has been the bottleneck that limits their applications. This paper reports a novel coupled ultrasonication-milling (CUM) process to exfoliate natural molybdenite powders to achieve few-layer MoS2 (FL-MoS2) nanosheets in the solvent of N-methyl-2-pyrrolidone (NMP) with polyvinylpyrrolidone (PVP) molecules. The synergistic effect of ultrasonication and sand milling highly enhanced the exfoliation efficiency, and the precursor of natural molybdenite powders minimizes the synthetic cost of FL-MoS2 nanosheets. The exfoliation of natural molybdenite powders was conducted in a home-made CUM system, mainly consisting of an ultrasonic cell disruptor and a ceramic sand mill. The samples were characterized by X-ray diffraction, UV-vis spectra, Raman spectra, FT-IR, SEM, TEM, AFM, and N2 adsorption-desorption. The factors that influence the exfoliation in the CUM process, including the initial concentration of natural molybdenite powders ( C in, 15-55 g L-1), ultrasonic power ( P u, 200-350 W), rotation speed of sand mill ( ω s, 1500-2250 r.p.m), exfoliation time ( t ex, 0.5-6 h), and the molar ratio of PVP unit to MoS2 ( R pm, 0-1), were systematically investigated. Under the optimal CUM conditions (i.e., C in = 45 g L-1, P u = 280 W, ω s = 2250 r.p.m and R pm = 0.5), the yield at t ex = 6 h reaches 21.6 %, and the corresponding exfoliation rate is as high as 1.42 g L-1 h-1. The exfoliation efficiency of the CUM mode is much higher than that of either the ultrasonication (U) mode or the milling (M) mode. The synergistic mechanism and influencing rules of the CUM process in exfoliating natural molybdenite powders were elaborated. The as-obtained FL-MoS2 nanosheets have a high specific surface area of 924 m2 g-1 and show highly enhanced electrocatalytic performance in hydrogen evolution reaction and good electrochemical sensing property in detecting ascorbic acid. The CUM process

Spectral analysis of allogeneic hydroxyapatite powders

Science.gov (United States)

Timchenko, P. E.; Timchenko, E. V.; Pisareva, E. V.; Vlasov, M. Yu; Red'kin, N. A.; Frolov, O. O.

2017-01-01

In this paper we discuss the application of Raman spectroscopy to the in vitro analysis of the hydroxyapatite powder samples produced from different types of animal bone tissue during demineralization process at various acid concentrations and exposure durations. The derivation of the Raman spectrum of hydroxyapatite is attempted by the analysis of the pure powders of its known constituents. Were experimentally found spectral features of hydroxyapatite, based on analysis of the line amplitude at wave numbers 950-965 cm-1 ((PO4)3- (ν1) vibration) and 1065-1075 cm-1 ((CO3)2-(ν1) B-type replacement). Control of physicochemical properties of hydroxyapatite was carried out by Raman spectroscopy. Research results are compared with an infrared Fourier spectroscopy.

Spectral analysis of allogeneic hydroxyapatite powders

International Nuclear Information System (INIS)

Timchenko, P E; Timchenko, E V; Pisareva, E V; Vlasov, M Yu; Red’kin, N A; Frolov, O O

2017-01-01

In this paper we discuss the application of Raman spectroscopy to the in vitro analysis of the hydroxyapatite powder samples produced from different types of animal bone tissue during demineralization process at various acid concentrations and exposure durations. The derivation of the Raman spectrum of hydroxyapatite is attempted by the analysis of the pure powders of its known constituents. Were experimentally found spectral features of hydroxyapatite, based on analysis of the line amplitude at wave numbers 950-965 cm -1 ((PO 4 ) 3- (ν 1 ) vibration) and 1065-1075 cm -1 ((CO 3 ) 2- (ν 1 ) B-type replacement). Control of physicochemical properties of hydroxyapatite was carried out by Raman spectroscopy. Research results are compared with an infrared Fourier spectroscopy. (paper)

Infrared spectral studies of various metal polyacrylates

International Nuclear Information System (INIS)

McCluskey, P.H.; Snyder, R.L.; Condrate, R.A. Sr.

1989-01-01

A new process for the production of high surface area, high reactivity ceramic oxide powders involves the bonding of metal cations to polymeric polyacrylate chains. This process results in the formation of a gelatinous metal polyacrylate precipitate which can be easily removed from the mother liquor, and then calcined to form a high density ceramic oxide. Using FTIR spectroscopy, the nature of the structural arrangements has been studied for metal complexes in the yttrium, lanthanum, aluminum, cerium, copper, and iron polyacrylates. Interpretation of the infrared spectra indicates that two types of metal complex formation occur in these precipitates, involving bidentate or bridging interactions. The type that is observed for a particular metal ion is dependent on its metal ion size

Synthesis and characterization of ceramic powders of pure and doped with trivalent erbium barium tungstate

International Nuclear Information System (INIS)

Sousa, R.B. de; Nascimento, V.A. do; Matos, J. M.E. de; Santos, M.R.M.C.

2014-01-01

This research proposes the synthesis and characterization of pure and doped with Er"3"+ (1 and 2 %) barium tungstate powders prepared by the coprecipitation method. In order to characterize the obtained powders were used X-Ray Diffractometry, Raman Spectroscopy and Fourier Transform Infrared Spectroscopy. According to the standard XRD spectra, the crystals exhibited the presence of tetragonal scheelite structure without the presence of secondary phases. Raman spectra showed the presence of eleven vibrational modes and two modes were observed in the infrared spectra. The synthesized oxides showed good crystallinity and structurally ordered at short and long-range. (author)

The stoichiometry of synthetic alunite as a function of hydrothermal aging investigated by solid-state NMR spectroscopy, powder X-ray diffraction and infrared spectroscopy

DEFF Research Database (Denmark)

Grube, Elisabeth; Nielsen, Ulla Gro

2015-01-01

The stoichiometry of a series of synthetic alunite (nominally KAl3(SO4)2(OH)6) samples prepared by hydrothermal methods as a function of reaction time (1 – 31 days) has been investigated by powder X-ray diffraction, Fourier transform infrared spectroscopy as well as solid-state 1H and 27Al magic...... of potassium defects present, from 17.261(1) to 17.324(5) Å. Solid-state 27Al MAS NMR revealed a decrease in the defect concentration as a function of time and showed the presence of 7-10 % impurities in the samples....

XRD, SEM and infrared study into the intercalation of sodium hexadecyl sulfate (SHS) into hydrocalumite.

Science.gov (United States)

Zhang, Ping; Wang, Tianqi; Zhang, Longlong; Wu, Daishe; Frost, Ray L

2015-12-05

Hydrocalumite (CaAl-LDH-Cl) interacted with a natural anionic surfactant, sodium hexadecyl sulfate (SHS), was performed using an intercalation method. To understand the intercalation behavior and characterize the resulting products, powder X-ray diffraction (XRD), scan electron microscopy (SEM) and mid-infrared (MIR) spectroscopy combined with near-infrared (NIR) spectroscopy technique were used. The XRD analysis indicated that SHS was intercalated into CaAl-LDH-Cl successfully, resulting in an expansion of the interlayer (from 0.78 nm to 2.74 nm). The bands of C-H stretching vibrations of SHS were observed in the near-infrared spectra, which indicated that the resulting products were indeed CaAl-LDH-SHS. In addition, the bands of water stretching vibrations and OH groups shifted to higher wavenumbers when SHS was intercalated into CaAl-LDH-Cl interlayer space. Copyright © 2015 Elsevier B.V. All rights reserved.

Fabrication of Spherical AlSi10Mg Powders by Radio Frequency Plasma Spheroidization

Science.gov (United States)

Wang, Linzhi; Liu, Ying; Chang, Sen

2016-05-01

Spherical AlSi10Mg powders were prepared by radio frequency plasma spheroidization from commercial AlSi10Mg powders. The fabrication process parameters and powder characteristics were investigated. Field emission scanning electron microscope, X-ray diffraction, laser particle size analyzer, powder rheometer, and UV/visible/infrared spectrophotometer were used for analyses and measurements of micrographs, phases, granulometric parameters, flowability, and laser absorption properties of the powders, respectively. The results show that the obtained spherical powders exhibit good sphericity, smooth surfaces, favorable dispersity, and excellent fluidity under appropriate feeding rate and flow rate of carrier gas. Further, acicular microstructures of the spherical AlSi10Mg powders are composed of α-Al, Si, and a small amount of Mg2Si phase. In addition, laser absorption values of the spherical AlSi10Mg powders increase obviously compared with raw material, and different spectra have obvious absorption peaks at a wavelength of about 826 nm.

Application of acid-modified Imperata cylindrica powder for latent fingerprint development.

Science.gov (United States)

Low, Wei Zeng; Khoo, Bee Ee; Aziz, Zalina Binti Abdul; Low, Ling Wei; Teng, Tjoon Tow; bin Abdullah, Ahmad Fahmi Lim

2015-09-01

A novel powdering material that utilizes acid-modified Imperata cylindrica (IC) powder for the development of fingermarks was studied. Experiments were carried out to determine the suitability, adherence quality and sensitivity of the acid-modified IC powder. Fingermarks of different constituents (eccrine, sebaceous and natural fingermarks) on different types of surfaces were used. Acid-modified IC powder was also used to develop fingermarks of different ages as well as aged fingermarks recovered from the water. From the visual inspection, acid-modified IC powder was able to interact with different fingermark constituents and produced distinct ridge details on the examined surfaces. It was also able to develop aged fingermarks and fingermarks that were submerged in water. A statistical comparison was made against the Sirchie® Hi-Fi black powder in terms of the powders' sensitivity and quality of the developed natural fingermarks. The image quality was analyzed using MITRE's Image Quality of Fingerprint (IQF) software. From the experiments, acid-modified IC powder has the potential as a fingermark development powder, although natural fingermarks developed by Sirchie® black powder showed better quality and sensitivity based on the results of the statistical comparison. Copyright © 2015 The Chartered Society of Forensic Sciences. Published by Elsevier Ireland Ltd. All rights reserved.

Graphene oxide powders with different oxidation degree, prepared by synthesis variations of the Hummers method

International Nuclear Information System (INIS)

Guerrero-Contreras, Jesus; Caballero-Briones, F.

2015-01-01

Graphene oxide (GO) powders with different oxidation degree estimated through the relative intensity of the infrared absorption bands related to oxygen containing groups were prepared through variations of the Hummers method. The GO powders were analyzed by Transmission Electron Microscopy, Energy dispersive spectroscopy, X-ray Photoelectron Spectroscopy, Fourier Transform Infrared Spectroscopy, Raman spectroscopy, X-ray Diffraction, UV–VIS spectroscopy and Electrical Resistance measurements. Several square micron GO sheets with low wrinkling were obtained. Oxygen to carbon ratio is around 0.2 in all the samples although a strong variance in the relative intensity of the oxygen related infrared bands is evident. Thus, the oxidation degree was estimated from the FTIR measurements using the quotient between the C–O related bands area to the total area under the spectra. FTIR shows presence of hydroxyl (–OH), epoxy (C–O–C), carboxyl (–COOH) and carbonyl (C=O) moieties and evidence of intermolecular interactions between adjacent groups. These interactions influence the exfoliation degree, the absorbance of the GO suspensions, as well as the electrical resistance, while the crystalline domain sizes, estimated from XRD and Raman do not show a noticeable behavior related with the composition and molecular structure. The results indicate that the electrical resistance is influenced mainly by the surface chemistry of the GO powders and not only by the O/C ratio. The control of the surface chemistry of GO powders would allow their use as additives in organic bulk heterojunction solar cells with enhanced photoconversion efficiency. - Highlights: • Powders of graphene oxide with different oxidation degree were prepared through variations of the Hummers method. • Raman spectroscopy and XRD demonstrated similar crystallite domain size in the samples. • Electrical resistance, exfoliation degree and optical absorption depend on the molecular structure. �

Graphene oxide powders with different oxidation degree, prepared by synthesis variations of the Hummers method

Energy Technology Data Exchange (ETDEWEB)

Guerrero-Contreras, Jesus; Caballero-Briones, F., E-mail: fcaballero@ipn.mx

2015-03-01

Graphene oxide (GO) powders with different oxidation degree estimated through the relative intensity of the infrared absorption bands related to oxygen containing groups were prepared through variations of the Hummers method. The GO powders were analyzed by Transmission Electron Microscopy, Energy dispersive spectroscopy, X-ray Photoelectron Spectroscopy, Fourier Transform Infrared Spectroscopy, Raman spectroscopy, X-ray Diffraction, UV–VIS spectroscopy and Electrical Resistance measurements. Several square micron GO sheets with low wrinkling were obtained. Oxygen to carbon ratio is around 0.2 in all the samples although a strong variance in the relative intensity of the oxygen related infrared bands is evident. Thus, the oxidation degree was estimated from the FTIR measurements using the quotient between the C–O related bands area to the total area under the spectra. FTIR shows presence of hydroxyl (–OH), epoxy (C–O–C), carboxyl (–COOH) and carbonyl (C=O) moieties and evidence of intermolecular interactions between adjacent groups. These interactions influence the exfoliation degree, the absorbance of the GO suspensions, as well as the electrical resistance, while the crystalline domain sizes, estimated from XRD and Raman do not show a noticeable behavior related with the composition and molecular structure. The results indicate that the electrical resistance is influenced mainly by the surface chemistry of the GO powders and not only by the O/C ratio. The control of the surface chemistry of GO powders would allow their use as additives in organic bulk heterojunction solar cells with enhanced photoconversion efficiency. - Highlights: • Powders of graphene oxide with different oxidation degree were prepared through variations of the Hummers method. • Raman spectroscopy and XRD demonstrated similar crystallite domain size in the samples. • Electrical resistance, exfoliation degree and optical absorption depend on the molecular structure. �

The effect of mixed oxidants and powdered activated carbon on the removal of natural organic matter.

Science.gov (United States)

Alvarez-Uriarte, Jon I; Iriarte-Velasco, Unai; Chimeno-Alanís, Noemí; González-Velasco, Juan R

2010-09-15

Present paper studies the influence of electrochemically generated mixed oxidants on the physicochemical properties of natural organic matter, and especially from the disinfection by-products formation point of view. The study was carried out in a full scale water treatment plant. Results indicate that mixed oxidants favor humic to non-humic conversion of natural organic matter. Primary treatment preferentially removes the more hydrophobic fraction. This converted the non-humic fraction in an important source of disinfection by-products with a 20% contribution to the final trihalomethane formation potential (THMFP(F)) of the finished water. Enhanced coagulation at 40 mg l(-1) of polyaluminium chloride with a moderate mixing intensity (80 rpm) and pH of 6.0 units doubled the removal efficiency of THMFP(F) achieved at full scale plant. However, gel permeation chromatography data revealed that low molecular weight fractions were still hardly removed. Addition of small amounts of powdered activated carbon, 50 mg l(-1), allowed reduction of coagulant dose by 50% whereas removal of THMFP(F) was maintained or even increased. In systems where mixed oxidants are used addition of powdered activated carbon allows complementary benefits by a further reduction in the THMFP(F) compared to the conventional only coagulation-flocculation-settling process. Copyright 2010 Elsevier B.V. All rights reserved.

Influence of Ultrafine 2CaO·SiO₂ Powder on Hydration Properties of Reactive Powder Concrete.

Science.gov (United States)

Sun, Hongfang; Li, Zishanshan; Memon, Shazim Ali; Zhang, Qiwu; Wang, Yaocheng; Liu, Bing; Xu, Weiting; Xing, Feng

2015-09-17

In this research, we assessed the influence of an ultrafine 2CaO·SiO₂ powder on the hydration properties of a reactive powder concrete system. The ultrafine powder was manufactured through chemical combustion method. The morphology of ultrafine powder and the development of hydration products in the cement paste prepared with ultrafine powder were investigated by scanning electron microscopy (SEM), mineralogical composition were determined by X-ray diffraction, while the heat release characteristics up to the age of 3 days were investigated by calorimetry. Moreover, the properties of cementitious system in fresh and hardened state (setting time, drying shrinkage, and compressive strength) with 5% ordinary Portland cement replaced by ultrafine powder were evaluated. From SEM micrographs, the particle size of ultrafine powder was found to be up to several hundred nanometers. The hydration product started formulating at the age of 3 days due to slow reacting nature of belitic 2CaO·SiO₂. The initial and final setting times were prolonged and no significant difference in drying shrinkage was observed when 5% ordinary Portland cement was replaced by ultrafine powder. Moreover, in comparison to control reactive powder concrete, the reactive powder concrete containing ultrafine powder showed improvement in compressive strength at and above 7 days of testing. Based on above, it can be concluded that the manufactured ultrafine 2CaO·SiO₂ powder has the potential to improve the performance of a reactive powder cementitious system.

Assessment of Natural radionuclides in Powdered milk Consumed in Iraq

Energy Technology Data Exchange (ETDEWEB)

Amin, Sahar A.; Al-ani, Rana R. [Environmental Research Center, University of Technology, Baghdad (Iraq); AL-kafaje, Mohammed S.M. [Department of Laser Engineering and Electronic Optics, University of Technology (Iraq)

2014-07-01

The activity concentrations of {sup 226}Ra, {sup 232}Th, and {sup 40}K radionuclides were measured for 10 brands of powdered milk samples consumed in Iraq, which are imported from different countries. The main detected activity corresponding to {sup 40}K with average activity of 290.661 BqKg{sup -1}, while the average activities of {sup 226}Ra and {sup 232}Th were below the detection level (B.D.L.). Results are compared with those of different countries worldwide. The total average annual effective doses due to intake of {sup 40}K from the ingestion of the powdered milk for children (2-7, 7-12, 12-17)y and adults (≥ 17 y) were estimated to be 82.21, 50.90, 29.75 and 22.55 μSvy{sup -1}, respectively. These results indicate no significant radiation dose to the public. The resulting data may serve as base-line levels of activity concentration in powdered milk in the area of study. (authors)

Comparative study between radioactive contamination in milk powder by chernobyl accident [137Cs] and natural radioactivity [40K

International Nuclear Information System (INIS)

Navarrete, J.M.; Martinez, T.; Cabrera, L.

2005-01-01

After the Chernobyl accident in 1986, Mexico imported from an European country 28,000 Tons of contaminated milk powder with the fission product 137 CS. When the contamination was detected, the alarm among the authorities and population spread out very quick and of course the product was retired at once from the foodstuff market. Nevertheless, the public panic grew up in such a manner, that even the way to manage and to dispose safely this material, considered highly dangerous, was largely discussed. Now, about two decades ago from this event, a study has been performed to compare the level of radioactivity due to both radioisotopes present in one saved sample: the artificial contaminant 137 CS, beside the natural, all around present 40 K, in order to evaluate in a more realistic way how risky was the management, possible consumption, and final disposition of this nourishment. This paper considers results obtained within an uncertainty degree equal to ±5%, and set up conclusions by comparing artificial and natural radioactivity present in that contaminated milk powder.

Dry powder segregation and flowability: Experimental and numerical studies

Science.gov (United States)

Ely, David R.

Dry powder blending is a very important industrial and physical process used in the production of numerous pharmaceutical dosage forms such as tablets, capsules, and dry powder aerosols. Key aspects of this unit operation are process monitoring and control. Process control is particularly difficult due to the complexity of particle-particle interactions, which arise from the adhesion/cohesion characteristics of interfaces and morphological characteristics such as particle size, shape, and dispersity. The effects of such characteristics need to be understood in detail in order to correlate individual particle properties to bulk powder properties. The present dissertation numerically and experimentally quantifies the mixing process to rationalize particle-particle interactions. In particular, near infrared spectroscopy (NIRS) was used to non-invasively characterize in real-time the blending processes and thus investigate the dynamics of blending under different operating conditions. A novel image analysis technique was developed to quantify the scale of segregation from images obtained non-destructively via near infrared chemical imaging (NIR-CI). Although NIR-CI data acquisition times are too long for real-time data collection, NIR-CI has an advantage, in that it provides the spatial distribution of the drug. Therefore, NIRS and NIR-CI are complementary techniques for investigating the complex process of blending dry powders and assessing end-product quality. Additionally, the discrete element method was used to investigate the effect of powder cohesion on the packing fraction. Simulations indicated an exponential relationship between the random loose packing fraction and cohesive forces. Specifically, the packing fraction decreased asymptotically with increased ratio of cohesive force to particle weight. Thus, increasing this force ratio above a critical value has negligible impact on the packing fraction. Such result directly impacts the Hausner ratio flowability

Effects of fuel properties on the natural downward smoldering of piled biomass powder: Experimental investigation

International Nuclear Information System (INIS)

He, Fang; Yi, Weiming; Li, Yongjun; Zha, Jianwen; Luo, Bin

2014-01-01

To validate the modeling of one-dimensional biomass smoldering and combustion, the effects of fuel type, moisture content and particle size on the natural downward smoldering of biomass powder have been investigated experimentally. A cylindrical reactor (inner size Φ26 cm × 22 cm) was constructed, and corn stalk, pine trunk, pyrolysis char and activated char from corn stalk were prepared as powders. The smoldering characteristics were examined for each of the four materials and for different moisture contents and particle sizes. The results revealed the following: 1) The maximum temperature in the fuel bed is only slightly affected by the fuel type and particle size. It increases gradually for original biomass and decreases slowly for chars with the development of the process. 2) The propagation velocity of the char oxidation front is significantly affected by the carbon density and ash content and nearly unaffected by moisture content and particle size. 3) The propagation velocity of the drying front is significantly affected by the moisture content, decreasing from over 10 times the propagation velocity of char oxidation front to about 3 times as the moisture content increased from 3 to 21%. - Highlights: • Natural downward smoldering of four materials, different moisture contents, and different particle sizes were investigated. • Propagation velocity of the char oxidation front differs significantly from that of the drying front. • Carbon density and ash content of fuel significantly affect propagation velocity of the char oxidation front

210Pb content in natural gas pipeline residues ('black-powder') and its correlation with the chemical composition

International Nuclear Information System (INIS)

Godoy, Jose Marcus; Carvalho, Franciane; Cordilha, Aloisio; Matta, Luiz Ernesto; Godoy, Maria Luiza

2005-01-01

The present work was carried out to assess the 210 Pb content in 'black-powder' found in pigging operations on gas pipelines in Brazil, in particular, on the Campos Basin gas pipeline. Additionally, the chemical composition of such deposits was determined and an eventual correlation with 210 Pb concentration evaluated. Typical 'black-powder' generated in the natural gas pipeline from Campos Basin oilfield contains mainly iron oxide (∼81%) and residual organic matter (∼9%). The 210 Pb content ranges from 4.9 to 0.04 kBq kg -1 and seems to be inversely correlated with the distance to the platforms. On the other hand, 226 Ra concentration is higher on the pipeline branch between the platform and the onshore installations. 228 Ra was only observed in few samples, in particular, in the samples with the highest 226 Ra content

Influence of Ultrafine 2CaO·SiO2 Powder on Hydration Properties of Reactive Powder Concrete

Directory of Open Access Journals (Sweden)

Hongfang Sun

2015-09-01

Full Text Available In this research, we assessed the influence of an ultrafine 2CaO·SiO2 powder on the hydration properties of a reactive powder concrete system. The ultrafine powder was manufactured through chemical combustion method. The morphology of ultrafine powder and the development of hydration products in the cement paste prepared with ultrafine powder were investigated by scanning electron microscopy (SEM, mineralogical composition were determined by X-ray diffraction, while the heat release characteristics up to the age of 3 days were investigated by calorimetry. Moreover, the properties of cementitious system in fresh and hardened state (setting time, drying shrinkage, and compressive strength with 5% ordinary Portland cement replaced by ultrafine powder were evaluated. From SEM micrographs, the particle size of ultrafine powder was found to be up to several hundred nanometers. The hydration product started formulating at the age of 3 days due to slow reacting nature of belitic 2CaO·SiO2. The initial and final setting times were prolonged and no significant difference in drying shrinkage was observed when 5% ordinary Portland cement was replaced by ultrafine powder. Moreover, in comparison to control reactive powder concrete, the reactive powder concrete containing ultrafine powder showed improvement in compressive strength at and above 7 days of testing. Based on above, it can be concluded that the manufactured ultrafine 2CaO·SiO2 powder has the potential to improve the performance of a reactive powder cementitious system.

Manufacture of Partially Biodegradable Composite Materials Based on PLA-Tires Powder: Process and Characterization

Directory of Open Access Journals (Sweden)

Carlos Rolando Rios-Soberanis

2013-01-01

Full Text Available This research work focuses on the processability and mechanical characterization of blends of polylactic acid (PLA and tire (elastomeric part. Wasted tires used as filler in the PLA matrix were reduced by two different processes (thermal shock and pyrolysis in order to acquire the solid residuals in powder to be characterized and compared. Elastomeric solids obtained from scraped tires were used as filler in the PLA matrix and mixed in a Brabender 60 cc mixer at different concentrations ranging from 0% to 60% of filler volume fraction. The blend was laminated, and then samples were obtained in order to undertake mechanical properties at tension and Izod impact tests. A fully detailed analysis on the solid powders by Differential Scanning Calorimeter (DSC, thermogravimetric analysis (TGA, infrared analysis (IR, and scanning electron microscopy analysis (SEM identified them as a rich source of carbon. Blends were characterized thermally and mechanically showing a direct effect due to the tire nature (thermoset rubber and concentration. Fracture mechanisms were also identified.

The mechanical and thermal characteristics of phenolic foam reinforced with kaolin powder and glass fiber fabric

Science.gov (United States)

Xiao, Wenya; Huang, Zhixiong; Ding, Jie

2017-12-01

In this work, kaolin powder and glass fiber fabric were added to PF in order to improve its thermal stability and mechanical property. Micro-structures of carbonized PF with kaolin powder were inspected by scanning electron microscopy (SEM) to demonstrate the filler’s pinning effect. SEM results illustrated modified PF had well morphology after high-temperature heat treatment. The Fourier transform infrared spectrometer (FTIR) test was carried out and found that kaolin powder only physically dispersed in PF. The compression test and thermal weight loss test were done on two groups of modified PF (Group A: add powder and fabric; Group B: add powder only). Results showed that all modified PF were better than pure PF, while foams with powder and fabric showed better mechanical characteristic and thermal stability compared with foams with powder only.

Low intensity natural gas infrared in sports centres; L'infrarouge a basse intensite au gaz naturel dans les centres sportifs

Energy Technology Data Exchange (ETDEWEB)

Lajoie, S. [Gaz Metropolitain, Montreal, PQ (Canada)

2002-09-30

Infrared devices are being employed more and more for heating buildings. They were traditionally used to heat large spaces higher than 3 metres, such as aviation hangars and industrial buildings. Natural gas infrared devices have found other applications, namely in sports centres, due in large part to the energy efficiency and the resulting comfort. There are three types of infrared devices: low intensity or low intensity tubes, high intensity, and catalytic infrared. Each type of device possesses specific characteristics and applications. For example, infrared tubes are used to uniformly heat a specific area. High intensity devices possess a more intense heat and concentrated in a confined space. Catalytic devices do not have flames, and they can be used in industrial drying processes and thermoforming. In the case of skating rinks, the use of low intensity natural gas infrared tubes is ideal. They reduce the crossed effects of ice cooling load and the spectators need for heat. This is due to infrared acting more on mass (spectators and bleachers) than ambient air. The author described the situation at the Val d'Or arena, Quebec where an energy saving project was initiated two years ago, involving the installation for one of the ice surfaces, of movement sensors to turn off infrared tubes when the rink is unoccupied. The payback period for such equipment is short. The case of the Soccerplex at Lachine, part of the larger City of Montreal, was also discussed. This sports centre comprises indoor soccer fields with 30 foot-high ceilings and large area covering 66,000 square feet (3 soccer fields). Once again, low intensity natural gas infrared tubes were installed and have proved successful.

Thermal conductivity model for powdered materials under vacuum based on experimental studies

Directory of Open Access Journals (Sweden)

N. Sakatani

2017-01-01

Full Text Available The thermal conductivity of powdered media is characteristically very low in vacuum, and is effectively dependent on many parameters of their constituent particles and packing structure. Understanding of the heat transfer mechanism within powder layers in vacuum and theoretical modeling of their thermal conductivity are of great importance for several scientific and engineering problems. In this paper, we report the results of systematic thermal conductivity measurements of powdered media of varied particle size, porosity, and temperature under vacuum using glass beads as a model material. Based on the obtained experimental data, we investigated the heat transfer mechanism in powdered media in detail, and constructed a new theoretical thermal conductivity model for the vacuum condition. This model enables an absolute thermal conductivity to be calculated for a powder with the input of a set of powder parameters including particle size, porosity, temperature, and compressional stress or gravity, and vice versa. Our model is expected to be a competent tool for several scientific and engineering fields of study related to powders, such as the thermal infrared observation of air-less planetary bodies, thermal evolution of planetesimals, and performance of thermal insulators and heat storage powders.

Synthesis of boehmite by hydrothermal treatment used as inorganic binder for alumina powder

International Nuclear Information System (INIS)

Lima, M.B.; Tercini, M.B.; Yoshimura, H.N.

2012-01-01

Presently, due to the concerns with the environment, it has been developed studies to replace the organic binder by an inorganic binder for forming of ceramic powders, in order to avoiding the generation of polluting gases during sintering (firing). A potential alternative is the use of boehmite, produced by hydrothermal treatment on the surfaces of the alumina powder, previously ground in a ball mill using zirconia milling media to produce hydrated phases on alumina powder which are converted to boehmite. In the treated alumina powders, it was observed the formation of boehmite phase by X-ray diffraction analysis and Fourier transformed infrared (FTIR) spectroscopy, demonstrating the efficiency of boehmite formation during the hydrothermal treatment at 150°C for 3 hours.(author)

Application of gamma irradiation for incorporation of rubber powder in the formulations of EPDM and natural rubber; Aplicacao da radiacao gama para incorporacao do po de borracha em formulacoes de borracha natural e EPDM

Energy Technology Data Exchange (ETDEWEB)

Kiyan, Ludmila Y.P.; Parra, Duclerc Fernandes; Lugao, Ademar Benevolo, E-mail: ludmilapozzo@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP/CQMA), Sao Paulo, SP (Brazil). Centro de Quimica e Meio Ambiente

2013-07-01

The objective of this work was to study the behavior of the recycling of rubber burrs in form of powder, of the rubber industry from EPDM rubber powder and natural rubber with SBR. The rubber powder was irradiated and reused in rubber artifacts formulations for classical vulcanization. The processed material was irradiated using a {sup 60}Co source in doses of 50, 100, 150 and 200 kGy and a dose rate of 5 kGy s-1 at room temperature. The radiation created devulcanization active sites for subsequent integration of the material (rubber powder) in formulations of commercial use. The processes were compared and their products characterized by analytical methods of the physical properties such as strength and elongation. Satisfactory results were found, noting a major spin-off of EPDM chain demonstrated by increased elongation.

Combined sol–gel and carbothermal synthesis of ZrC–TiC powders for composites

Energy Technology Data Exchange (ETDEWEB)

Umalas, Madis [Institute of Physics, University of Tartu, Riia 142, 51014, Tartu (Estonia); Estonian Nanotechnology Competence Centre, Riia 142, 51014, Tartu (Estonia); Hussainova, Irina, E-mail: irina.hussainova@ttu.ee [Department of Materials Engineering, Tallinn University of Technology, Ehitajate 5, 19086, Tallinn (Estonia); ITMO University, Kronverksky 49, St. Petersburg, 197101 (Russian Federation); Reedo, Valter [Institute of Physics, University of Tartu, Riia 142, 51014, Tartu (Estonia); Young, Der-Liang [Department of Materials Engineering, Tallinn University of Technology, Ehitajate 5, 19086, Tallinn (Estonia); Cura, Erkin; Hannula, Simo-Pekka [Department of Materials Science and Engineering, Aalto University, School of Chemical Technology, POB 16200, Aalto, 00076 (Finland); Lõhmus, Rünno [Institute of Physics, University of Tartu, Riia 142, 51014, Tartu (Estonia); Estonian Nanotechnology Competence Centre, Riia 142, 51014, Tartu (Estonia); Lõhmus, Ants [Institute of Physics, University of Tartu, Riia 142, 51014, Tartu (Estonia)

2015-03-01

The TiC–ZrC binary compound of nanostructured powders was synthesised by combination of sol–gel and carbothermal reduction. The polymeric precursor of the blend was produced by sol–gel process from titanium tetrabutoxide, zirconium tetrabutoxide and benzene-1.4-diol; then carbothermally reduced to the TiC–ZrC blend at 1600 °C in an inert environment. The chemical reactions occurring in the system were monitored by infrared spectrometry. Stable alkoxide solution was obtained by adding acetylacetone to avoid premature gelation of the metal alkoxide mixture. A solid solution of ZrTiC{sub 2} was produced by spark plasma sintering at temperature of 2000 °C. - Highlights: • A polymeric precursor of TiC–ZrC blend was synthesised by sol–gel process. • The polymeric precursor synthesis was studied by infrared spectroscopy. • TiC–ZrC powder blend was carbothermally reduced from polymeric precursor. • TiC–ZrC powder blend was sintered to ZrTiC{sub 2} solid solution by spark plasma sintering. • Sintered ZrTiC{sub 2} have good mechanical properties.

Combined sol–gel and carbothermal synthesis of ZrC–TiC powders for composites

International Nuclear Information System (INIS)

Umalas, Madis; Hussainova, Irina; Reedo, Valter; Young, Der-Liang; Cura, Erkin; Hannula, Simo-Pekka; Lõhmus, Rünno; Lõhmus, Ants

2015-01-01

The TiC–ZrC binary compound of nanostructured powders was synthesised by combination of sol–gel and carbothermal reduction. The polymeric precursor of the blend was produced by sol–gel process from titanium tetrabutoxide, zirconium tetrabutoxide and benzene-1.4-diol; then carbothermally reduced to the TiC–ZrC blend at 1600 °C in an inert environment. The chemical reactions occurring in the system were monitored by infrared spectrometry. Stable alkoxide solution was obtained by adding acetylacetone to avoid premature gelation of the metal alkoxide mixture. A solid solution of ZrTiC 2 was produced by spark plasma sintering at temperature of 2000 °C. - Highlights: • A polymeric precursor of TiC–ZrC blend was synthesised by sol–gel process. • The polymeric precursor synthesis was studied by infrared spectroscopy. • TiC–ZrC powder blend was carbothermally reduced from polymeric precursor. • TiC–ZrC powder blend was sintered to ZrTiC 2 solid solution by spark plasma sintering. • Sintered ZrTiC 2 have good mechanical properties

Characterization of sonicated natural zeolite/ferric chloride hexahydrate by infrared spectroscopy

Science.gov (United States)

Prasetyo, T. A. B.; Soegijono, B.

2018-03-01

The characteristics of sonicated Bayah natural zeolite with and without ferric chloride hexahydrate solution using infrared method has been studied. High intensity ultrasonic waves were exposed to the samples for 40 min, 80 min and 120 min. Infra red spectra analysis was conducted to evaluate zeolite vibrational spectrum contributions, namely, the vibrations from the framework of the zeolite, from the charge-balancing cations, and from the relatively isolated groups, such as the surface OH groups and their behavior after sonication process. An addition of FeCl3.6H2O and sonication process on natural zeolite improved secondary building units link by forming oxygen bridges and also close relationship with duration of applied high intensity ultrasonic process. Longer ultrasonic process resulted in more increment of O-H absorbance.

Studies on the Effect of Pomegranate Rind Powder Extract as Natural Antioxidant in Chicken Meat Balls During Refrigerated Storage

Directory of Open Access Journals (Sweden)

Savala Chandralekha

2012-04-01

Full Text Available Trials were conducted to study the effect of pomegranate rind powder extract as natural antioxidant in chicken meat balls during refrigerated storage. Significantly (p<0.05 lower values for cooking loss, pH and 2-thiobarbituric acid (2-TBARS values and higher values for emulsion stability were obtained due to the incorporation of pomegranate rind powder extract at 5 percent level followed by 2.5 percent level than the other treatments. There was a significant (p<0.05 increase in cooking loss, pH, 2-TBARS values and free fatty acid content as the storage period progressed from 0 to 8 days, however emulsion stability of chicken meat balls decreased significantly (p<0.05 during the course of refrigeration. Microbial quality evaluation revealed that chicken meat balls incorporated with pomegranate rind powder extract at 5 percent level had significantly (p<0.05 lower standard plate count during refrigerated storage and a significant (p<0.05 increase in microbial load was observed. Organoleptic evaluation indicated that addition of pomegranate rind powder extract at 5 and 2.5 percent levels to chicken meat balls registered significantly (p<0.05 higher sensory scores for various eating quality attributes than the other treatments. However there was a significant (p<0.05 in all the organoleptic attributes of the product as the storage period increased.

Preparation of lanthanum ferrite powder at low temperature

Energy Technology Data Exchange (ETDEWEB)

Andoulsi, R.; Horchani-Naifer, K.; Ferid, M., E-mail: karima_horchani@yahoo.com [Physical Chemistry Laboratory of Mineral Materials and their Applications, Hammam-Lif (Tunisia)

2012-01-15

Single lanthanum ferrite phase was successfully prepared at low processing temperature using the polymerizable complex method. To implement this work, several techniques such as differential scanning calorimetry, X-ray diffraction, Fourier Transform Infrared Spectroscopy, scanning electron microscopy and BET surface area measurements were used. Throw the obtained results, it was shown that steps of preparing the powder precursor and temperature of its calcination are critical parameters for avoiding phase segregation and obtaining pure lanthanum ferrite compound. Thus, a single perovskite phase was obtained at 600 deg C. At this temperature, the powder was found to be fine and homogeneous with an average crystallite size of 13 nm and a specific surface area of 12.5 m{sup 2}.g{sup -1}. (author)

Effects of Polyethylene Grafted Maleic Anhydride on the Mechanical, Morphological, and Swelling Properties of Poly (Vinyl Chloride / Epoxidized Natural Rubber / Kenaf Core Powder Composites

Directory of Open Access Journals (Sweden)

Rohani Abdul Majid

2014-10-01

Full Text Available The effects of polyethylene grafted maleic anhydride (PE-g-MA on the properties of poly (vinyl chloride/epoxidized natural rubber (PVC/ENR kenaf core powder composites were studied, with four different loadings of kenaf core powder (5, 10, 15, and 20 phr. The tensile properties indicated that the strength and elongation at break of the composites exhibited an increase for samples with PE-g-MA. Morphological analysis using a scanning electron microscope (SEM showed better dispersion of kenaf fiber with the addition of PE-g-MA and less kenaf powder agglomeration. Furthermore, the swelling index indicated that composites with PE-g-MA showed lower toluene absorption than composites without PE-g-MA.

Infrared astronomy

International Nuclear Information System (INIS)

Setti, G.; Fazio, G.

1978-01-01

This volume contains lectures describing the important achievements in infrared astronomy. The topics included are galactic infrared sources and their role in star formation, the nature of the interstellar medium and galactic structure, the interpretation of infrared, optical and radio observations of extra-galactic sources and their role in the origin and structure of the universe, instrumental techniques and a review of future space observations. (C.F.)

Operation whey powder. Anatomy of a German scandal

Energy Technology Data Exchange (ETDEWEB)

Brunner, E

1987-04-03

The odyssey of the contaminated whey powder finally has come to an end, and the 5000 tonnes of whey now are designated for decontamination by means of an ion exchange technique. The article throws light upon the political and economic reasons that sent the whey powder off on a chaotic journey. It is worth mentioning in this context that the natural radioactivity of inorganic fertilizers is much higher than that of the whey powder in question.

Advances in beryllium powder consolidation simulations

International Nuclear Information System (INIS)

Reardon, B.J.

1998-01-01

A fuzzy logic based multiobjective genetic algorithm (GA) is introduced and the algorithm is used to optimize micromechanical densification modeling parameters for warm isopressed beryllium powder, HIPed copper powder and CIPed/sintered and HIPed tantalum powder. In addition to optimizing the main model parameters using the experimental data points as objective functions, the GA provides a quantitative measure of the sensitivity of the model to each parameter, estimates the mean particle size of the powder, and determines the smoothing factors for the transition between stage 1 and stage 2 densification. While the GA does not provide a sensitivity analysis in the strictest sense, and is highly stochastic in nature, this method is reliable and reproducible in optimizing parameters given any size data set and determining the impact on the model of slight variations in each parameter

Toxicity of Sodium Bicarbonate to Fish from Coal-Bed Natural Gas Production in the Tongue and Powder River Drainages, Montana and Wyoming

Science.gov (United States)

,

2006-01-01

This study evaluates the sensitivity of aquatic life to sodium bicarbonate (NaHCO3), a major constituent of coal-bed natural gas-produced water. Excessive amounts of sodium bicarbonate in the wastewater from coal-bed methane natural gas production released to freshwater streams and rivers may adversely affect the ability of fish to regulate their ion uptake. The collaborative study focuses on the acute and chronic toxicity of sodium bicarbonate on select fish species in the Tongue and Powder River drainages in southeastern Montana and northeastern Wyoming. Sodium bicarbonate is not naturally present in appreciable concentrations within the surface waters of the Tongue and Powder River drainages; however, the coal-bed natural gas wastewater can reach levels over 1,000 milligrams per liter. Large concentrations have been shown to be acutely toxic to native fish (Mount and others, 1997). In 2003, with funding and guidance provided by the U.S. Environmental Protection Agency, the Montana Fish, Wildlife, and Parks and the U.S. Geological Survey initiated a collaborative study on the potential effects of coal-bed natural gas wastewater on aquatic life. A major goal of the study is to provide information to the State of Montana Water Quality Program needed to develop an aquatic life standard for sodium bicarbonate. The standard would allow the State, if necessary, to establish targets for sodium bicarbonate load reductions.

An experimental investigation of temperature rise during compaction of pharmaceutical powders.

Science.gov (United States)

Krok, Alexander; Mirtic, Andreja; Reynolds, Gavin K; Schiano, Serena; Roberts, Ron; Wu, Chuan-Yu

2016-11-20

During pharmaceutical powder compaction, temperature rise in the compressed powder can affect physiochemical properties of the powder, such as thermal degradation and change in crystallinity. Thus, it is of practical importance to understand the effect of process conditions and material properties on the thermal response of pharmaceutical formulations during compaction. The aim of this study was to examine the temperature rise of pharmaceutical powders during tableting, in particular, to explore how the temperature rise depends on material properties, compression speed and tablet shape. Three grades of microcrystalline cellulose (MCC) were considered: MCC Avicel pH 101, MCC Avicel pH 102 and MCC DG. These powders were compressed using a compaction simulator at various compaction speeds (10-500mm/s). Flat faced, shallow convex and normal convex tablets were produced and temperature distributions on the surface of theses tablets upon ejection were examined using an infrared thermoviewer. It was found that an increase in the compaction speed led to an increase in the average surface temperature. A higher surface temperature was induced when the powder was compressed into a tablet with larger surface curvature. This was primarily due to the increasing degree of powder deformation (i.e. the volume reduction) and the effect of interparticule/wall friction. Copyright © 2016 Elsevier B.V. All rights reserved.

Hygroscopic behavior of lyophilized acerola pulp powder

Directory of Open Access Journals (Sweden)

Luciana C. Ribeiro

2016-03-01

Full Text Available ABSTRACT Powder products are characterized by their practicality and long life. However, fruit powders have high hygroscopicity and tend to agglomerate due to its hydrophilic nature. The isotherms of equilibrium moisture content apply to the study of dehydrated food preservation potential. Acerola is a nutritionally rich fruit, with great economic and industrial potential. The objective of this study was to analyse acerola powder adsorption isotherms obtained by lyophilization and characterize the powder obtained from lyophilized acerola pulp. Analysis of hygroscopicity, solubility and degree of caking were performed. Isotherms were represented by the mathematical models of GAB, BET, Henderson and Oswin, at temperatures of 25, 35 and 45 °C. According to the results, the obtained powder showed hygroscopicity of 5.96 g of absorbed water 100g-1 of solids, solubility of 95.08% and caking of 14.12%. The BET model showed the best fit to the adsorption isotherms of the acerola pulp powder obtained by lyophilization. The obtained isotherm was of type III, with a "J" shape. There was an inversion of the effect of temperature on the isotherms of acerola powders.

Zirconia powders production by precipitation: state-of-art review

International Nuclear Information System (INIS)

Oliveira, Ana Paula Almeida de; Torem, Mauricio Leonardo

1994-01-01

The important role played by zirconia in advanced ceramics can be attributed to its excellent wear and corrosion resistance and refractory character. The polymorphic nature of zirconia made the controlled addition of stabilizing oxides or the constraining effect of a dense ceramics matrix necessary to maintain high parameters had a significant influence on powder properties and on compacted powder behaviour in sintering. Particle shape and size, purity and crystalline structure were specially influenced by precipitation parameters. Therefore, this work presented a review of the state of the art in zirconia powder production and in the recent research on precipitation of that powder. (author)

Characterization of natural topaz for dosimetric applications in the therapeutic range

International Nuclear Information System (INIS)

Souza, Divanizia do Nascimento

2002-01-01

The thermoluminescence (TL) and the thermally stimulated exoelectron emission of Brazilian natural topaz samples from Minas Gerais were analysed aiming the use of this mineral for dosimetric applications. Topaz is an aluminium fluorosilicate with a fairly constant chemical composition of Al 2 SiO 4 (F,OH) 2 . The major variation in the structure among different samples is related to the OH/F concentration ratio. In the present work, samples cut from rolled pebbles, powdered samples and composites were used. The composites (dosimeters) were prepared with powdered topaz embedded in powdered Teflon or glass. The dosimetric characterization of the composites showed that the dosimeters present a linear response in the range of therapeutic doses, slow isothermic fading and a strong TL dependence with radiation energy. The TL was also combined with the X-ray diffraction, infrared and Raman spectroscopic techniques to identify the charge carrier traps and those of the recombination centres, that are essential aspects to understand the processes of light emission in natural colourless topaz. It was observed that the main charge trapping centers in the topaz are due to various OH-related defects, and that the thermal treatments can change the concentration of the recombination centers. Implantations with chromium, aluminium and iron ions into colourless samples were performed, and they were efficient to produce TL modifications in topaz. (author)

New gonioscopy system using only infrared light.

Science.gov (United States)

Sugimoto, Kota; Ito, Kunio; Matsunaga, Koichi; Miura, Katsuya; Esaki, Koji; Uji, Yukitaka

2005-08-01

To describe an infrared gonioscopy system designed to observe the anterior chamber angle under natural mydriasis in a completely darkened room. An infrared light filter was used to modify the light source of the slit-lamp microscope. A television monitor connected to a CCD monochrome camera was used to indirectly observe the angle. Use of the infrared system enabled observation of the angle under natural mydriasis in a completely darkened room. Infrared gonioscopy is a useful procedure for the observation of the angle under natural mydriasis.

Deformed liquid marbles: Freezing drop oscillations with powders

KAUST Repository

Marston, Jeremy; Zhu, Y.; Vakarelski, Ivan Uriev; Thoroddsen, Sigurdur T

2012-01-01

In this work we show that when a liquid drop impacts onto a fine-grained hydrophobic powder, the final form of the drop can be very different from the spherical form with which it impacts. In all cases, the drop rebounds due to the hydrophobic nature of the powder. However, we find that above a critical impact speed, the drop undergoes a permanent deformation to a highly non-spherical shape with a near-complete coverage of powder, which then freezes the drop oscillations during rebound. © 2012 Elsevier B.V.

Deformed liquid marbles: Freezing drop oscillations with powders

KAUST Repository

Marston, Jeremy

2012-09-01

In this work we show that when a liquid drop impacts onto a fine-grained hydrophobic powder, the final form of the drop can be very different from the spherical form with which it impacts. In all cases, the drop rebounds due to the hydrophobic nature of the powder. However, we find that above a critical impact speed, the drop undergoes a permanent deformation to a highly non-spherical shape with a near-complete coverage of powder, which then freezes the drop oscillations during rebound. © 2012 Elsevier B.V.

Factors affecting the electrostatic charge of ceramic powders

International Nuclear Information System (INIS)

Lorite, I.; Romero, J.; Fernandez, J. F.

2011-01-01

The phenomenon of electrostatic charge in ceramic powders takes place when the particle surfaces enter in contact between them or with the containers. The accumulation of electrostatic charge is of relevance in ceramic powders in view of their insulating character and the risk of explosions during the material handling. In this work the main factors that affect the appearance of intrinsic charge and tribo-charge in ceramic powder have been studied. In ceramic powders of alumina it has been verified that the smallest particle sizes present an increase of the electrostatic charge of negative polarity. A correlation has been observed between the nature of the OH -surface groups and the electrostatic charge. The intrinsic charge and the tribocharge in ceramic powders can be diminished by compensating the surface groups that support the charge. The dry dispersion of nanoparticles on microparticles allows surface charge compensation with a noticeable modification of the powder agglomeration. (Author) 19 refs.

Sensory analysis of cosmetic powders: personal care ingredients and emulsions.

Science.gov (United States)

Moussour, M; Lavarde, M; Pensé-Lhéritier, A-M; Bouton, F

2017-02-01

The powders are ingredients increasingly used in the formulation of cosmetic products for the sensory qualities they give. The objective of this study was the development of a lexicon and a referential for sensory characterization of these pure raw materials as well as formulations which contain them. Eleven expert panellists from Ecole de biologie industrielle de Cergy (France) developed a lexicon and a referential based on 12 powders of different chemical natures. The selected attributes were then used for performing a quantitative descriptive profile of two powders and an emulsion containing or not one of these two powders. A lexicon has been established through a consensus approach of the panel. It contains seven attributes that allow the evaluation of the powders in four phases: the appearance, the pickup, the application and the after-feel. This lexicon contains definitions and assessment protocols and provides references products. The quantitative descriptive profile of two powders of the same chemical nature, but different in physical quality showed significant differences in sensory level between products. These same attributes used to evaluate an emulsion containing the powder or not allowed to prove the contribution of these raw materials on the sensory specificities of the emulsion. The lexicon developed in this study can be used for assessment of other powders but also to define the quantities necessary to put in the formulation to meet the sensory characteristics of these raw materials powder. © 2016 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

High-definition infrared thermography of ice nucleation and propagation in wheat under natural frost conditions and controlled freezing.

Science.gov (United States)

Livingston, David P; Tuong, Tan D; Murphy, J Paul; Gusta, Lawrence V; Willick, Ian; Wisniewski, Micheal E

2018-04-01

An extremely high resolution infrared camera demonstrated various freezing events in wheat under natural conditions. Many of those events shed light on years of misunderstanding regarding freezing in small grains. Infrared thermography has enhanced our knowledge of ice nucleation and propagation in plants through visualization of the freezing process. The majority of infrared analyses have been conducted under controlled conditions and often on individual organs instead of whole plants. In the present study, high-definition (1280 × 720 pixel resolution) infrared thermography was used under natural conditions to visualize the freezing process of wheat plants during freezing events in 2016 and 2017. Plants within plots were found to freeze one at a time throughout the night and in an apparently random manner. Leaves on each plant also froze one at a time in an age-dependent pattern with oldest leaves freezing first. Contrary to a common assumption that freezing begins in the upper parts of leaves; freezing began at the base of the plant and spread upwards. The high resolution camera used was able to verify that a two stage sequence of freezing began within vascular bundles. Neither of the two stages was lethal to leaves, but a third stage was demonstrated at colder temperatures that was lethal and was likely a result of dehydration stress; this stage of freezing was not detectable by infrared. These results underscore the complexity of the freezing process in small grains and indicate that comprehensive observational studies are essential to identifying and selecting freezing tolerance traits in grain crops.

Advances in food powder agglomeration engineering.

Science.gov (United States)

Cuq, B; Gaiani, C; Turchiuli, C; Galet, L; Scher, J; Jeantet, R; Mandato, S; Petit, J; Murrieta-Pazos, I; Barkouti, A; Schuck, P; Rondet, E; Delalonde, M; Dumoulin, E; Delaplace, G; Ruiz, T

2013-01-01

Food powders are used in everyday life in many ways and offer technological solutions to the problem of food production. The natural origin of food powders, diversity in their chemical composition, variability of the raw materials, heterogeneity of the native structures, and physicochemical reactivity under hydrothermal stresses contribute to the complexity in their behavior. Food powder agglomeration has recently been considered according to a multiscale approach, which is followed in the chapter layout: (i) at the particle scale, by a presentation of particle properties and surface reactivity in connection with the agglomeration mechanisms, (ii) at the mechanisms scale, by describing the structuration dynamics of agglomerates, (iii) at the process scale, by a presentation of agglomeration technologies and sensors and by studying the stress transmission mode in the powder bed, and finally (iv) by an integration of the acquired knowledge, thanks to a dimensional analysis carried out at each scale. Copyright © 2013 Elsevier Inc. All rights reserved.

Radiation dose to Malaysian infants from natural radionuclides via consumption of powdered milk

Energy Technology Data Exchange (ETDEWEB)

Uwatse, Onosohwo Bemigho; Olatunji, Michael Adekunle; Khandaker, Mayeen Uddin; Amin, Yusoff Mohd. [Department of Physics, University of Malaya, Kuala Lumpur 50603 (Malaysia)

2015-04-24

Milk is the basic food stuff for the infants because they generally consume more milk on a daily basis as its minerals and proteins are essential for their growth and development, therefore, it is very important to assess the natural radioactivity levels and the associated dose in the widely consumed powered infant’s milk. As a result, 14 brands of infant’s powdered milk were collected from different supermarkets around Selangor, Malaysia and analysed for {sup 226}Ra, {sup 232}Th and {sup 40}K activities. The obtained mean activity of {sup 226}Ra, {sup 232}Th and {sup 40}K are 3.05±1.84, 2.55±2.48 and 99.1±69.5 Bqkg{sup −1}, respectively. Among the analysed milk samples, the brand from Philippines (Lactogen) showed low level of radioactivity while Singaporean brand (S26 SMA Gold) showed the highest. The estimated mean annual effective doses due to the ingestion of natural radionuclides in the sampled milk are 635 and 111 µSv for infant ≤ 1y and infant 1-2y, respectively. The obtained dose value does not yet pose any significant radiological hazards to the population under investigation comparing with the 1.0 mSvy{sup −1} recommended by ICRP for all ages.

Radiation dose to Malaysian infants from natural radionuclides via consumption of powdered milk

Science.gov (United States)

Uwatse, Onosohwo Bemigho; Olatunji, Michael Adekunle; Khandaker, Mayeen Uddin; Amin, Yusoff Mohd.

2015-04-01

Milk is the basic food stuff for the infants because they generally consume more milk on a daily basis as its minerals and proteins are essential for their growth and development, therefore, it is very important to assess the natural radioactivity levels and the associated dose in the widely consumed powered infant's milk. As a result, 14 brands of infant's powdered milk were collected from different supermarkets around Selangor, Malaysia and analysed for 226Ra, 232Th and 40K activities. The obtained mean activity of 226Ra, 232Th and 40K are 3.05±1.84, 2.55±2.48 and 99.1±69.5 Bqkg-1, respectively. Among the analysed milk samples, the brand from Philippines (Lactogen) showed low level of radioactivity while Singaporean brand (S26 SMA Gold) showed the highest. The estimated mean annual effective doses due to the ingestion of natural radionuclides in the sampled milk are 635 and 111 µSv for infant ≤ 1y and infant 1-2y, respectively. The obtained dose value does not yet pose any significant radiological hazards to the population under investigation comparing with the 1.0 mSvy-1 recommended by ICRP for all ages.

Radiation dose to Malaysian infants from natural radionuclides via consumption of powdered milk

International Nuclear Information System (INIS)

Uwatse, Onosohwo Bemigho; Olatunji, Michael Adekunle; Khandaker, Mayeen Uddin; Amin, Yusoff Mohd.

2015-01-01

Milk is the basic food stuff for the infants because they generally consume more milk on a daily basis as its minerals and proteins are essential for their growth and development, therefore, it is very important to assess the natural radioactivity levels and the associated dose in the widely consumed powered infant’s milk. As a result, 14 brands of infant’s powdered milk were collected from different supermarkets around Selangor, Malaysia and analysed for 226 Ra, 232 Th and 40 K activities. The obtained mean activity of 226 Ra, 232 Th and 40 K are 3.05±1.84, 2.55±2.48 and 99.1±69.5 Bqkg −1 , respectively. Among the analysed milk samples, the brand from Philippines (Lactogen) showed low level of radioactivity while Singaporean brand (S26 SMA Gold) showed the highest. The estimated mean annual effective doses due to the ingestion of natural radionuclides in the sampled milk are 635 and 111 µSv for infant ≤ 1y and infant 1-2y, respectively. The obtained dose value does not yet pose any significant radiological hazards to the population under investigation comparing with the 1.0 mSvy −1 recommended by ICRP for all ages

Comparison of different drying methods on the physical properties, bioactive compounds and antioxidant activity of raspberry powders.

Science.gov (United States)

Si, Xu; Chen, Qinqin; Bi, Jinfeng; Wu, Xinye; Yi, Jianyong; Zhou, Linyan; Li, Zhaolu

2016-04-01

Dehydration has been considered as one of the traditional but most effective techniques for perishable fruits. Raspberry powders obtained after dehydration can be added as ingredients into food formulations such as bakery and dairy products. In this study, raspberry powders obtained by hot air drying (HAD), infrared radiation drying (IRD), hot air and explosion puffing drying (HA-EPD), infrared radiation and microwave vacuum drying (IR-MVD) and freeze drying (FD) were compared on physical properties, bioactive compounds and antioxidant activity. Drying techniques affected the physical properties, bioactive compounds and antioxidant activity of raspberry powders greatly. FD led to significantly higher (P drying methods. However, thermal drying techniques, especially combined drying methods, were superior to FD in final total polyphenol content, total flavonoid content and antioxidant activity. The combined drying methods, especially IR-MVD, showed the highest total polyphenol content (123.22 g GAE kg(-1) dw) and total flavonoid content (0.30 g CAE kg(-1) dw). Additionally, IR-MVD performed better in antioxidant activity retention. Overall, combined drying methods, especially IR-MVD, were found to result in better quality of raspberry powders among the thermal drying techniques. IR-MVD could be recommended for use in the drying industry because of its advantages in time saving and nutrient retention. © 2015 Society of Chemical Industry.

Near-infrared spectral downshifting in Sr$_{(3−x)}$(VO$_4$)

Indian Academy of Sciences (India)

infrared (NIR) radiation in Sr 3 (VO 4 ) 2 :Nd 3 + phosphor is reported. The prepared materials were characterized by X-ray powder diffraction(XRD) and photoluminescence (PL) properties along with steady state luminescence time decay curves ...

Planar compaction of ceramic powders with mining explosives

International Nuclear Information System (INIS)

Stuivinga, M.; Verbeek, H.J.; Carton, E.P.

2000-01-01

Shock compaction experiments of B 4 C powders have been performed using a planar configuration. The powders were contained between metal plates. On top of the upper plate, having a thickness of about 10 mm, was a layer of mining explosives. For this configuration, computer simulations have been performed with use of the hydrocode Autodyn. In comparison with the cylindrical compaction process the planar compaction process appears to be quite different. The reason is the very low detonation velocity of the used mining explosives (2-4 km/s), which is much lower than the sound and shock speeds of the steel plate, in combination with the relatively large thickness of the metal layer. As a result, the nature of the compaction process of the powder initially more resembles a quasi-static compaction process than a shock compaction process. Due to the quasi-static nature of the compaction, the pressure release in the powder after compression is very gradual. Therefore, no strong rarefaction waves leading to high tensile stresses in the compact arise. Flat plates (10x10 cm, 0.6-0.8 cm thick) of Al (20-30 vol %) infiltrated B 4 C have been fabricated using this configuration

Synthesis and Characterizations of Fine Silica Powder from Rice Husk Ash

International Nuclear Information System (INIS)

Khin Muyar Latt

2011-12-01

The silica content of rice husk ash obtained from the uncontrolled burning temperature of gasifier was 90.4%. The obtained rice husk ash was an amorphous form of silica with low crystallization by XRD. The sodium hydroxide solution, 1.5N, 2N, 2.5N and 3N, respectively was used to prepare sodium silicate solution by extraction method. The product silica was produced by acid precipitation method used 4.5N, 5.5N and 6.5N sulphuric acid solution. The highest yield percent of product silica extraced by 2.5N sodium hydroxide solution at 5N sulphuric acid solution was 88.84%. The crystallize size of product silica containing silicalite as a source of silica was 86nm at this condition. The fine silica powder was produced by acid refluxing mothod used 5.5N, 6N and 6.5N hydrochloric acid solution. 98% of pure fine silica powder can be produced from the product silica by refluxing method. The crystallize size of fine silica powder was 54nm. The distribution of the crystallize size of product silica powder could be found uniform in size and agglomeration. The Fourier Transform Infrared Spectra indicate the hydrogen bonded silinol groups and siloxane groups in product silica and fine silica powder.

The nature of cometary dust as determined from infrared observations

Science.gov (United States)

Swamy, K. S. Krishna; Sandford, Scott A.; Allamandola, Louis J.; Witteborn, Fred C.; Bregman, Jesse D.

1989-01-01

The infrared measurements of comets, the compositional information available from interplanetary dust particles (IDPs), and the recent results of flybys to Comet Halley can help in restricting the nature and composition of cometary dust models (c.f., Proceedings of the 20th ESLAB Symposium on Exploration of Halley's Comet, 1986). Researchers tried to incorporate some of these results into a coherent model to account for the observed cometary infrared emission. The presence of 10 and 3.4 micron features in Comet Halley (c.f. Bregman et al. 1987; Wickramasinghe and Allen 1986) indicated the presence of at least two components in the grain material, namely silicates and some form of amorphous carbon. These two components could reside in separate grains or may be parts of composite particles. Both these cases have been considered (see Krishna Swamy el a. 1988a, 1988b). In the absence of refractive index data for cometary analogs, the authors used the optical constants of olivine-rich lunar material 12009.48 (Perry et al. 1972) for the infrared region and that of alpha:C-H film for amorphous carbon (angus et al. 1986). For the visible region, a value of m = 1.38-0.39i was used for the silicates, and values published by Arakawa et al. (1985) were used for the amorphous carbon. These materials should give a representative behavior of the expected results. The model results were compared to observational data. The strength of the 3.4 micron and 10 micron features relative to the adjacent continuum, as well as the slope of the continuum between 2500 and 1250 cm(exp -1) (4 to 8 microns), were used as criteria for comparison. Model calculations with alpha approx. equals -3.5, and also the size distribution function inferred for Comet Halley, with a mass fraction (X) of silicate to amorphous carbon grains of about 40 to 1 can fit the data. A good match is obtained for the infrared spectra of Comets Halley and West from a 40 to 1 mixture of silicate and amorphous carbon grains

Characteristics of Inconel Powders for Powder-Bed Additive Manufacturing

Directory of Open Access Journals (Sweden)

Quy Bau Nguyen

2017-10-01

Full Text Available In this study, the flow characteristics and behaviors of virgin and recycled Inconel powder for powder-bed additive manufacturing (AM were studied using different powder characterization techniques. The results revealed that the particle size distribution (PSD for the selective laser melting (SLM process is typically in the range from 15 μm to 63 μm. The flow rate of virgin Inconel powder is around 28 s·(50 g−1. In addition, the packing density was found to be 60%. The rheological test results indicate that the virgin powder has reasonably good flowability compared with the recycled powder. The inter-relation between the powder characteristics is discussed herein. A propeller was successfully printed using the powder. The results suggest that Inconel powder is suitable for AM and can be a good reference for researchers who attempt to produce AM powders.

CATCHING QUENCHING GALAXIES: THE NATURE OF THE WISE INFRARED TRANSITION ZONE

Energy Technology Data Exchange (ETDEWEB)

Alatalo, Katherine; Appleton, Philip N.; Rich, Jeffrey A. [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States); Cales, Sabrina L. [Department of Astronomy, Faculty of Physical and Mathematical Sciences, Universidad de Concepción, Casilla 160-C, Concepción (Chile); Kewley, Lisa J. [Research School of Astronomy and Astrophysics, Australian National University, Cotter Road, Weston, ACT 2611 (Australia); Lacy, Mark [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Lisenfeld, Ute [Departamento de Física Teórica y del Cosmos, Universidad de Granada, Granada (Spain); Nyland, Kristina, E-mail: kalatalo@caltech.edu [Physics Department, New Mexico Tech, Socorro, NM 87801 (United States)

2014-10-10

We present the discovery of a prominent bifurcation between early-type galaxies and late-type galaxies, in [4.6]-[12] μm colors from the Wide Field Infrared Survey Explorer (WISE). We then use an emission-line diagnostic comparison sample to explore the nature of objects found both within and near the edges of this WISE infrared transition zone (IRTZ). We hypothesize that this bifurcation might be due to the presence of hot dust and polyaromatic hydrocarbon (PAH) emission features in late-type galaxies. Using a sample of galaxies selected through the Shocked Poststarburst Galaxy Survey (SPOGS), we are able to identify galaxies with strong Balmer absorption (EW(Hδ) > 5 Å) as well as emission lines inconsistent with star formation (deemed SPOG candidates, or SPOGs*) that lie within the optical green valley. Seyferts and low-ionization nuclear emission line regions, whose u – r colors tend to be red, are strongly represented within IRTZ, whereas SPOGs* tend to sit near the star-forming edge. Although active galactic nuclei are well represented in the IRTZ, we argue that the dominant IRTZ population is composed of galaxies that are in late stages of transitioning across the optical green valley, shedding the last of their remnant interstellar media.

Electrospun composites of PHBV/pearl powder for bone repairing

Directory of Open Access Journals (Sweden)

Jingjing Bai

2015-08-01

Full Text Available Electrospun fiber has highly structural similarity with natural bone extracelluar matrix (ECM. Many researches about fabricating organic–inorganic composite materials have been carried out in order to mimic the natural composition of bone and enhance the biocompatibility of materials. In this work, pearl powder was added to the poly (3-hydroxybutyrate-co-3-hydroxyvalerate (PHBV and the composite nanofiber scaffold was prepared by electrospinning. Mineralization ability of the composite scaffolds can be evaluated by analyzing hydroxyapatite (HA formation on the surface of nanofiber scaffolds. The obtained composite nanofiber scaffolds showed an enhanced mineralization capacity due to incorporation of pearl powder. The HA formed amount of the composite scaffolds was raised as the increase of pearl powder in composite scaffolds. Therefore, the prepared PHBV/pearl composite nanofiber scaffolds would be a promising candidate as an osteoconductive composite material for bone repairing.

A robust quantitative near infrared modeling approach for blend monitoring.

Science.gov (United States)

Mohan, Shikhar; Momose, Wataru; Katz, Jeffrey M; Hossain, Md Nayeem; Velez, Natasha; Drennen, James K; Anderson, Carl A

2018-01-30

This study demonstrates a material sparing Near-Infrared modeling approach for powder blend monitoring. In this new approach, gram scale powder mixtures are subjected to compression loads to simulate the effect of scale using an Instron universal testing system. Models prepared by the new method development approach (small-scale method) and by a traditional method development (blender-scale method) were compared by simultaneously monitoring a 1kg batch size blend run. Both models demonstrated similar model performance. The small-scale method strategy significantly reduces the total resources expended to develop Near-Infrared calibration models for on-line blend monitoring. Further, this development approach does not require the actual equipment (i.e., blender) to which the method will be applied, only a similar optical interface. Thus, a robust on-line blend monitoring method can be fully developed before any large-scale blending experiment is viable, allowing the blend method to be used during scale-up and blend development trials. Copyright © 2017. Published by Elsevier B.V.

Hydrothermal synthesis and characterization of hydroxyapatite and fluorhydroxyapatite nano-size powders

International Nuclear Information System (INIS)

Montazeri, Leila; Javadpour, Jafar; Shokrgozar, Mohammad Ali; Bonakdar, Shahin; Javadian, Sayfoddin

2010-01-01

Pure hydroxyapatite (HAp) and fluoride-containing apatite powders (FHAp) were synthesized using a hydrothermal method. The powders were assessed by x-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscope (SEM) and F-selective electrode. X-ray diffraction results revealed the formation of single phase apatite structure for all the compositions synthesized in this work. However, the addition of a fluoride ion led to a systematic shift in the (3 0 0) peak of the XRD pattern as well as modifications in the FTIR spectra. It was found that the efficiency of fluoride ion incorporation decreased with the increase in the fluoride ion content. Fluorine incorporation efficiency was around 60% for most of the FHAp samples prepared in the current study. Smaller and less agglomerated particles were obtained by fluorine substitution. The bioactivity of the powder samples with different fluoride contents was compared by performing cell proliferation, alkaline phosphatase (ALP) and Alizarin red staining assays. Human osteoblast cells were used to assess the cellular responses to the powder samples in this study. Results demonstrated a strong dependence of different cell activities on the level of fluoridation.

Biosorption of Basic Green 4 from aqueous solution by Ananas comosus (pineapple) leaf powder.

Science.gov (United States)

Chowdhury, Shamik; Chakraborty, Sagnik; Saha, Papita

2011-06-01

Biosorption characteristics of Ananas comosus (pineapple) leaf powder was investigated for decolorization of Basic Green 4 (BG 4), a cationic dye from its aqueous solutions employing a batch experimental set-up. Parameters that influence the sorption process such as pH, biosorbent dosage, contact time, initial dye concentration and temperature were systematically studied. The optimum conditions for removal of BG 4 were found to be pH 9.0, contact time=150 min, biosorbent dosage=5.0 g L(-1), initial dye concentration=50 mg L(-1). The temperature had a strong influence on the biosorption process. Further, the biosorbent was characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and Brunauer, Emmett, Teller (BET) surface area and pore size analysis. Experimental biosorption data were modeled by Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherms. The biosorption process followed the Langmuir isotherm model with high coefficients of correlation (R(2)>0.99) at different temperatures. The pseudo second order kinetic model fitted well in correlation to the experimental results. Activation energy of the biosorption process (E(a)) was found to be 45.79 kJ mol(-1) by using the Arrhenius equation, indicating chemisorption nature of BG 4 sorption onto pineapple leaf powder. Thermodynamic parameters suggest that the biosorption process is spontaneous and exothermic in nature. Overall, the present findings suggest that this environmentally friendly, efficient and low-cost biosorbent may be useful for the removal of BG 4 from aqueous media. Copyright © 2011 Elsevier B.V. All rights reserved.

Synthesis of Nickel and Nickel Hydroxide Nano powders by Simplified Chemical Reduction

International Nuclear Information System (INIS)

Tientong, J.; Garcia, S.; Thurber, C.R.; Golden, T.D.

2014-01-01

Nickel nano powders were synthesized by a chemical reduction of nickel ions with hydrazine hydrate at ph ∼ 12.5. Sonication of the solutions created a temperature of 54-65 °C to activate the reduction reaction of nickel nanoparticles. The solution ph affected the composition of the resulting nanoparticles. Nickel hydroxide nanoparticles were formed from an alkaline solution (ph ∼10) of nickel-hydrazine complexed by dropwise titration. X-ray diffraction of the powder and the analysis of the resulting Williamson-Hall plots revealed that the particle size of the powders ranged from 12 to 14 nm. Addition of polyvinylpyrrolidone into the synthesis decreased the nickel nanoparticle size to approximately 7 nm. Dynamic light scattering and scanning electron microscopy confirmed that the particles were in the nanometer range. The structure of the synthesized nickel and nickel hydroxide nanoparticles was identified by X-ray diffraction and Fourier transform infrared spectroscopy.

Synthesis of Uranium nitride powders using metal uranium powders

International Nuclear Information System (INIS)

Yang, Jae Ho; Kim, Dong Joo; Oh, Jang Soo; Rhee, Young Woo; Kim, Jong Hun; Kim, Keon Sik

2012-01-01

Uranium nitride (UN) is a potential fuel material for advanced nuclear reactors because of their high fuel density, high thermal conductivity, high melting temperature, and considerable breeding capability in LWRs. Uranium nitride powders can be fabricated by a carbothermic reduction of the oxide powders, or the nitriding of metal uranium. The carbothermic reduction has an advantage in the production of fine powders. However it has many drawbacks such as an inevitable engagement of impurities, process burden, and difficulties in reusing of expensive N 15 gas. Manufacturing concerns issued in the carbothermic reduction process can be solved by changing the starting materials from oxide powder to metals. However, in nitriding process of metal, it is difficult to obtain fine nitride powders because metal uranium is usually fabricated in the form of bulk ingots. In this study, a simple reaction method was tested to fabricate uranium nitride powders directly from uranium metal powders. We fabricated uranium metal spherical powder and flake using a centrifugal atomization method. The nitride powders were obtained by thermal treating those metal particles under nitrogen containing gas. We investigated the phase and morphology evolutions of powders during the nitriding process. A phase analysis of nitride powders was also a part of the present work

Removal of Malachite Green Dye by Mangifera indica Seed Kernel Powder

Science.gov (United States)

Singh, Dilbagh; Sowmya, V.; Abinandan, S.; Shanthakumar, S.

2017-11-01

In this study, batch experiments were carried out to study the adsorption of Malachite green dye from aqueous solution by Mangifera indica (mango) seed kernel powder. The mango seed kernel powder was characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. Effect of various parameters including pH, contact time, adsorbent dosage, initial dye concentration and temperature on adsorption capacity of the adsorbent was observed and the optimized condition for maximum dye removal was identified. Maximum percentage removal of 96% was achieved with an adsorption capacity of 22.8 mg/g at pH 6 with an initial concentration of 100 mg/l. The equilibrium data were examined to fit the Langmuir and Freundlich isotherm models. Thermodynamic parameters for the adsorption process were also calculated.

Characterization of calcium phosphate powders originating from Phyllacanthus imperialis and Trochidae Infundibulum concavus marine shells

International Nuclear Information System (INIS)

Tămăşan, M.; Ozyegin, L.S.; Oktar, F.N.; Simon, V.

2013-01-01

The study reports the preparation and characterization of powders consisting of the different phases of calcium phosphates that were obtained from the naturally derived raw materials of sea-shell origins reacted with H 3 PO 4 . Species of sea origin, such as corals and nacres, attracted a special interest in bone tissue engineering area. Nacre shells are built up of calcium carbonate in aragonite form crystallized in an organic matrix. In this work two natural marine origin materials (shells of echinoderm Sputnik sea urchin — Phyllacanthus imperialis and Trochidae Infundibulum concavus mollusk) were involved in the developing powders of calcium phosphate based biomaterials (as raw materials for bone-scaffolds) by hotplate and ultrasound methods. Thermal analyses of the as-prepared materials were made for an assessment of the thermal behavior and heat treatment temperatures. Samples from both sea shells each of them prepared by the above mentioned methods were subjected to thermal treatments at 450 °C and 850 °C in order to evaluate the crystalline transformations of the calcium phosphate structures in the heating process. By X-ray diffraction analyses various calcium phosphate phases were identified. In Sputnik sea urchins originated samples were found predominantly brushite and calcite as a small secondary phase, while in Trochidae I. concavus samples mainly monetite and HA phases were identified. Thermal treatment at 850 °C resulted flat-plate whitlockite crystals — β-MgTCP [(Ca, Mg) 3 (PO 4 ) 2 ] for both samples regardless the preparation method (ultrasound or hotplate) or the targeted Ca/P molar ratio according with XRD patterns. Scanning electron microscopy and Fourier transformed infrared spectroscopy were involved more in the characterization of these materials and the good correlations of the results of these methods were made. - Highlights: ► Calcium phosphate powders are obtained from the crushed shells of 2 “marine” species and H 3 PO 4

Characterization of calcium phosphate powders originating from Phyllacanthus imperialis and Trochidae Infundibulum concavus marine shells

Energy Technology Data Exchange (ETDEWEB)

Tămăşan, M., E-mail: monica.tamasan@phys.ubbcluj.ro [Babeş-Bolyai University, Faculty of Physics and Interdisciplinary Research Institute on Bio-Nano-Sciences, Cluj-Napoca (Romania); Ozyegin, L.S. [Marmara University, Istanbul (Turkey); Oktar, F.N. [Marmara University, Faculty of Engineering, Department of Bioengineering, Göztepe Campus, Kadıköy 34722, Istanbul (Turkey); Marmara University, School of Health Related Professions, Department of Medical Imaging Technics, Haydarpaşa Campus, Tıbbiye Street, 49, Üsküdar 34668, Istanbul (Turkey); Marmara University, Nanotechnology and Biomaterials Application and Research Centre, Göztepe Campus, Kadıköy 34722, Istanbul (Turkey); Simon, V. [Babeş-Bolyai University, Faculty of Physics and Interdisciplinary Research Institute on Bio-Nano-Sciences, Cluj-Napoca (Romania)

2013-07-01

The study reports the preparation and characterization of powders consisting of the different phases of calcium phosphates that were obtained from the naturally derived raw materials of sea-shell origins reacted with H{sub 3}PO{sub 4}. Species of sea origin, such as corals and nacres, attracted a special interest in bone tissue engineering area. Nacre shells are built up of calcium carbonate in aragonite form crystallized in an organic matrix. In this work two natural marine origin materials (shells of echinoderm Sputnik sea urchin — Phyllacanthus imperialis and Trochidae Infundibulum concavus mollusk) were involved in the developing powders of calcium phosphate based biomaterials (as raw materials for bone-scaffolds) by hotplate and ultrasound methods. Thermal analyses of the as-prepared materials were made for an assessment of the thermal behavior and heat treatment temperatures. Samples from both sea shells each of them prepared by the above mentioned methods were subjected to thermal treatments at 450 °C and 850 °C in order to evaluate the crystalline transformations of the calcium phosphate structures in the heating process. By X-ray diffraction analyses various calcium phosphate phases were identified. In Sputnik sea urchins originated samples were found predominantly brushite and calcite as a small secondary phase, while in Trochidae I. concavus samples mainly monetite and HA phases were identified. Thermal treatment at 850 °C resulted flat-plate whitlockite crystals — β-MgTCP [(Ca, Mg){sub 3} (PO{sub 4}){sub 2}] for both samples regardless the preparation method (ultrasound or hotplate) or the targeted Ca/P molar ratio according with XRD patterns. Scanning electron microscopy and Fourier transformed infrared spectroscopy were involved more in the characterization of these materials and the good correlations of the results of these methods were made. - Highlights: ► Calcium phosphate powders are obtained from the crushed shells of 2 �

Ninety Years of Powder Diffraction: from Birth to Maturity

International Nuclear Information System (INIS)

Paszkowicz, W.

2006-01-01

The expression ''powder diffraction '' denotes the phenomenon of diffraction of any electromagnetic waves or particles on polycrystalline (powdered, bulk or thin film) materials which is used in a wide variety experimental settings. The X-ray powder-diffraction method was devised and developed during the First World War (1916) by a Dutch/Swiss team, Peter Debye and Paul Scherrer, in Goettingen, Germany, and independently, marginally later, by an American, Albert W. Hull in Schenectady, USA. The birth of powder diffraction came four years after the discovery of the phenomenon of single-crystal diffraction made in 1912 by Walther Friedrich, Paul Knipping and Max Laue in Munich and developed from 1912/1913 by William Henry Bragg (father) and William Lawrence Bragg (son), and later by many others. Powder diffraction became a milestone towards an understanding of the nature of materials, especially of those which cannot be prepared in the form of suitable single crystals, and permitted rapid progress in solid state physics and chemistry. The events leading to the discovery of powder-diffraction phenomenon are briefly reviewed. The importance of synchrotron powder diffraction studies, which have developed since 1980s, is emphasised. (author)

Electrodeposition fabrication of Co-based superhydrophobic powder coatings in non-aqueous electrolyte

Science.gov (United States)

Chen, Zhi; Hao, Limei; Duan, Mengmeng; Chen, Changle

2013-05-01

A rapid, facile, one-step process was developed to fabricate Co-based superhydrophobic powder coatings on the stainless steel surfaces with a nonaqueous electrolyte by the electrodeposition method. The structure and composition of the superhydrophobic surfaces were characterized by means of scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and contact angle measurement. The results show that the special hierarchical structures along with the low surface energy lead to the high superhydrophobicity of the substrate surface. The shortest process of constructing the superhydrophobic surface is only 30 seconds, the high contact angle is greater than 160°, and the rolling angle is less than 2°. The method can be used to fabricate the superhydrophobic powder coatings at any conductive cathodic surface, and the as-prepared superhydrophobic powder coatings have advantages of transferability, repairability, and durability. It is expected that this facile method will accelerate the large-scale production of superhydrophobic material.

Combined control of morphology and polymorph in spray drying of mannitol for dry powder inhalation

Science.gov (United States)

Lyu, Feng; Liu, Jing J.; Zhang, Yang; Wang, Xue Z.

2017-06-01

The morphology and polymorphism of mannitol particles were controlled during spray drying with the aim of improving the aerosolization properties of inhalable dry powders. The obtained microparticles were characterized using scanning electron microscopy, infrared spectroscopy, differential scanning calorimetry, powder X-ray diffraction and inhaler testing with a next generation impactor. Mannitol particles of varied α-mannitol content and surface roughness were prepared via spray drying by manipulating the concentration of NH4HCO3 in the feed solution. The bubbles produced by NH4HCO3 led to the formation of spheroid particles with a rough surface. Further, the fine particle fraction was increased by the rough surface of carriers and the high α-mannitol content. Inhalable dry powders with a 29.1 ± 2.4% fine particle fraction were obtained by spray-drying using 5% mannitol (w/v)/2% NH4HCO3 (w/v) as the feed solution, proving that this technique is an effective method to engineer particles for dry powder inhalation.

High-definition infrared thermography of ice nucleation and propagation in wheat under natural frost conditions and controlled freezing

Science.gov (United States)

Infrared thermography has been used to visualize the freezing process in plants and has greatly enhanced our knowledge of ice nucleation and propagation in plants. The majority of IR analyses have been conducted under controlled rather than natural conditions and often on plant parts instead of wh...

The performances of natural gas infrared radiation in paints baking; Les performances de l`infrarouge gaz pour la cuisson des peintures

Energy Technology Data Exchange (ETDEWEB)

Lourdou, I. [Gaz de France, 75 - Paris (France). Centre d`essais de recherches sur les utilisations du gaz

1998-04-01

The direction of research of Gaz de France (GdF) company, in association with the centre for technical studies of aeraulic and thermal industries (CETIAT), has carried out infrared radiation baking tests on real painted parts using natural gas burners. Tests were performed on the Erica test facility. The development of the use of infrared gas burners in the mechanical industry requires an optimum use of this technology in the baking cycle. (J.S.)

Preparation and characterization of Dendrobium officinale powders through superfine grinding.

Science.gov (United States)

Meng, Qingran; Fan, Haoran; Chen, Feng; Xiao, Tiancun; Zhang, Lianfu

2018-03-01

Dendrobium officinale has been used in China for several thousand years as a health food and has become one of the most expensive tea materials worldwide as a result of extremely scarce resources in the wild and an increasing demand. Hence, it is very important to improve the depth and width of its application. In the present study, the physico-chemical, surface chemistry and thermal properties of micron range particles and coarse particles prepared by superfine grinding and shear pulverization were investigated. As the particle size decreased, the specific surface area of D. officinale powders increased significantly. Microscopy observations confirmed that superfine grinding effectively changed the original structure of D. officinale. The Fourier transform infrared spectroscopy spectra depicted the characteristic bands shifted in terms of absorbance and/or wave number as the powder particle size decreased. The crystallinity and intensity of the crystal peaks of D. officinale powders increased as the particle size decreased. Moisture sorption isotherms suggested that superfine powders were more unstable as a result of the increase in surface area, as well as the exposure of polar groups. The results of the present study suggest that superfine grinding may provide new methods of processing for D. officinale with respect to further enhancement of its application value. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

A Natural Cream-to-Powder Formulation Developed for the Prevention of Diaper Dermatitis in Diaper-Wearing Infants and Children: Barrier Property and In-Use Tolerance Studies.

Science.gov (United States)

Gunt, Hemali B; Levy, Stanley B; Lutrario, Celeste A

2018-05-01

Diaper dermatitis is a common condition that develops in the diaper area due to factors such as elevated moisture, increased skin surface pH, and exposure to irritants from urine and feces. These factors suggest interventions to prevent or treat diaper dermatitis such as exposing the skin to air, frequent diaper changes, and thorough cleansing of the diaper area. Barrier creams and powders also have a role in preventing and treating diaper dermatitis. We developed a cream-to-powder product with a formula based on corn starch and other natural ingredients for use in the diaper area. Dye exclusion study: The barrier properties of the cream-to-powder product were assessed using a dye exclusion protocol. Skin color at treated and untreated forearm sites was measured at baseline and after exposure to crystal violet stain. The cream-to-powder product's ability to inhibit the water-soluble dye from reaching the skin was judged by comparing color changes at the treated and untreated sites. Tolerance-in-use study: The safety of the cream-to-powder product was assessed in a four-week tolerance-in-use study conducted in a group of 52 diaper-wearing infants and toddlers. Subjects' parents/guardians applied the cream-to-powder product at each diaper change. A pediatrician judged safety endpoints of erythema, dryness, and edema in the diaper area at baseline and at study end. Parents/guardians also completed a questionnaire at study end. These studies have complied with Good Clinical Practices (GCP/ICH). The cream-to-powder product prevented about 70% of the test dye from reaching the skin surface, demonstrating its ability to supplement the skin barrier. The tolerance-in-use study showed no statistically significant changes in any of the safety endpoints; there were no adverse events. Parents/guardians responses to the cream-to-powder product were overwhelmingly positive. Taken together, these results support that the cream-to-powder formulation is safe and effective for

Infrared Irradiation: Toward Green Chemistry, a Review.

Science.gov (United States)

Escobedo, René; Miranda, René; Martínez, Joel

2016-03-26

This review provides a comprehensive overview of where infrared irradiation has been employed, mainly as regards activating green mode for natural products extractions, as well as to favor a reaction, highlighting its actual importance. It is also underlined that infrared irradiation heating has been around for a long time; however, only in the last eighteen years have many of its advantages been applied to satisfy a wide range of chemical processes, natural products extractions, and for the promotion of many kinds of reactions. In addition, it is brought to light that near infrared irradiation is more efficient than middle and far infrared irradiations, being easily controllable and with the quality of a fast responding heat source. Thus, the main objective of this review is to offer infrared irradiation as an alternative clean energy source to activate reactions, in addition to favor the selective extraction of natural products, all of which is within the Green Chemistry protocol. Some recent results from our laboratory are also included.

A comparison of compacting and caking behaviour of carbonate-based washing powders

OpenAIRE

Leaper, M.C.; Leach, V.; Taylor, P.M.; Prime, D.C.

2013-01-01

Two types of sodium carbonate powder produced by spray drying (SD) and dry neutralisation (DN) were studied for their compaction properties using a uniaxial compression tester. Dry neutralised sodium carbonate showed a greater resistance to compression and also produced a weaker compact when compressed to 100kPa. Differential Scanning Calorimetry (DSC) showed that both types of powder were predominantly amorphous in nature. Moisture sorption measurements showed that both powders behaved in a ...

Bursting Smoke as an Infrared Countermeasure

OpenAIRE

Amarjit Singh; P. J. Kamale; S. A. Joshi; L. K. Bankar

1998-01-01

This paper describes the experimental setup for the evaluation of bursting smoke for anti-infrared role using SR-5000 spectroradiometer and a source of IR radiation (8-13 micrometer) using cadmium-mercury-telluride (CMI) detector cooled by liquid nitrogen. The particle size and shape of the powders used in the bursting smokes were determined microscopically using Carl Zeiss Jena Neophot- 21. Highest attenuation of 97 -lOO percent was produced for about 12 s using a mixture of bronze fl...

The application of near infrared spectroscopy (NIR technique for

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Sandor Barabassy

2001-06-01

Full Text Available The production of cow’s milk in Hungary fluctuates by 15-20 % annualy. Surplus milk is dried into powder and can also be converted to modified milk powders using techniques such as ultra filtration. From approximetely 20.000 tonnes, of all milk powder types, 3.000 tonnes, is converted using ultra filtration technology. Multivariable near infrared (NIR calibration was performed on powder mixtures of whole milk, skimmed milk, whey, retenate (protein concentrate and lactose for rapid fat, protein, lactose, water and ash content determination. More than 150 samples were prepared and measured in two NIRS labs (Scottish Agriculture College – SAC – Aberdeen and University of Horticulture and Food Science - UHFS – Budapest. The results obtained from the same samples were compared. The aims of the study were: 1. Rapid quantitative and qualitative determination of mixtures of milk powder products using NIR technique. 2. Comparison of the results achieved in Aberdeen (SAC and Budapest (UHFS institutes. The mass per cent varied between 0.0-2.8% for fat, 0.0-80% for protein, 6.6-100 % for lactose, 0.0-5.0 % for water and 0.0-8.0 % for ash. High correlation coefficients (0.97-0.99 were found for all five components.

Natural precursor based hydrothermal synthesis of sodium carbide for reactor applications

Science.gov (United States)

Swapna, M. S.; Saritha Devi, H. V.; Sebastian, Riya; Ambadas, G.; Sankararaman, S.

2017-12-01

Carbides are a class of materials with high mechanical strength and refractory nature which finds a wide range of applications in industries and nuclear reactors. The existing synthesis methods of all types of carbides have problems in terms of use of toxic chemical precursors, high-cost, etc. Sodium carbide (Na2C2) which is an alkali metal carbide is the least explored one and also that there is no report of low-cost and low-temperature synthesis of sodium carbide using the eco-friendly, easily available natural precursors. In the present work, we report a simple low-cost, non-toxic hydrothermal synthesis of refractory sodium carbide using the natural precursor—Pandanus. The formation of sodium carbide along with boron carbide is evidenced by the structural and morphological characterizations. The sample thus synthesized is subjected to field emission scanning electron microscopy (FESEM), x-ray powder diffraction (XRD), ultraviolet (UV)—visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), Raman, and photoluminescent (PL) spectroscopic techniques.

Mechanochemical synthesis of ultrafine Ce2S3 powder

International Nuclear Information System (INIS)

Tsuzuki, T.; McCormick, P.G.

1998-01-01

Full text: Rare earth sulphides have been receiving an increasing attraction for various applications including infrared window materials and magneto-optical devices. In particular, Ce 2 S 3 has been under intensive study for use as a red pigment to replace toxic cadmium sulfoselenide. The conventional method for synthesising Ce 2 S 3 is the sulphidization of the element or sesquioxide with hydrogen sulphide gas. However, the method usually requires a high-temperature process (>1000 deg C), and hence coarse particles larger than the optimal size of ∼ 2 S 3 powder by mechanochemical processing using X-ray diffraction spectroscopy, BET surface area analysis and transmission electron microscopy. Mechanical milling of the mixture of a cerium salt and an alkali/alkali-earth sulphide powders led to a solid state displacement reaction in a steady-state manner, forming Ce 2 S 3 nanoparticles in a salt by-product matrix. After a simple washing process to remove the salt by-product, ultrafine Ce 2 S 3 particles with sizes of 20 - 200 nm having an orthorhombic structure were obtained. Using a diluent and mechanically alloyed CaS nanoparticles in the starting powder, particles of only a cubic γ-Ce 2 S 3 phase with sizes of 10 - 80 nm were formed

Infrared observations of extragalactic sources

International Nuclear Information System (INIS)

Kleinmann, D.E.

1977-01-01

The available balloon-borne and airborne infrared data on extragalactic sources, in particular M 82, NGC 1068 and NGC 253, is reviewed and discussed in the context of the extensive groundbased work. The data is examined for the clues they provide on the nature of the ultimate source of the energy radiated and on the mechanism(s) by which it is radiated. Since the discovery of unexpectedly powerful infrared radiation from extragalactic objects - a discovery now about 10 years old - the outstanding problems in this field have been to determine (1) the mechanism by which prodigious amounts of energy are released in the infrared, and (2) the nature of the underlying energy source. (Auth.)

New Strategies for Powder Compaction in Powder-based Rapid Prototyping Techniques

OpenAIRE

Budding, A.; Vaneker, T.H.J.

2013-01-01

In powder-based rapid prototyping techniques, powder compaction is used to create thin layers of fine powder that are locally bonded. By stacking these layers of locally bonded material, an object is made. The compaction of thin layers of powder mater ials is of interest for a wide range of applications, but this study solely focuses on the application for powder -based three-dimensional printing (e.g. SLS, 3DP). This research is primarily interested in powder compaction for creating membrane...

Egg Shell and Oyster Shell Powder as Alternatives for Synthetic Phosphate: Effects on the Quality of Cooked Ground Pork Products.

Science.gov (United States)

Cho, Min Guk; Bae, Su Min; Jeong, Jong Youn

2017-01-01

This study aimed to determine the optimal ratio of natural calcium powders (oyster shell and egg shell calcium) as synthetic phosphate replacers in pork products. Ground pork samples were subjected to six treatments, as follows: control (-) (no phosphate added), control (+) (0.3% phosphate blend added), treatment 1 (0.5% oyster shell calcium powder added), treatment 2 (0.3% oyster shell calcium powder and 0.2% egg shell calcium powder added), treatment 3 (0.2% oyster shell calcium powder and 0.3% egg shell calcium powder added), and treatment 4 (0.5% egg shell calcium powder added). The addition of natural calcium powders resulted in an increase in the pH values of meat products, regardless of whether they were used individually or mixed. The highest cooking loss was observed ( p cooking loss in samples with natural calcium powder added was similar ( p >0.05) to that in the positive control samples. CIE L* values decreased as the amount of added egg shell calcium powder increased. CIE a* values were higher ( p egg shell powder (treatment 2 or 3) was effective for the improvement of textural properties of the pork products. The findings show that the combined use of 0.2% oyster shell calcium and 0.3% egg shell calcium should enable the replacement of synthetic phosphate in the production of cooked pork products with desirable qualities.

Corrosion-resistant powder-metallurgy stainless steel powders and compacts therefrom

International Nuclear Information System (INIS)

Klar, E.; Ro, D.H.; Whitman, C.I.

1980-01-01

Disclosed is a process for improving the corrosion resistance of a stainless steel powder or compact thereof wherein the powder is produced by atomizing a melt of metals in an oxidizing environment whereby the resulting stainless steel powder is surface-enriched in silicon oxides. The process comprises adding an effective proportion of modifier metal to the melt prior to the atomization, the modifier metal selected from the group consisting of tin, aluminum, lead, zinc, magnesium, rare earth metals and like metals capable of enrichment about the surface of the resulting atomized stainless steel powder and effective under reductive sintering conditions in the depletion of the silicon oxides about the surface; and sintering the resulting atomized powder or a compact thereof under reducing conditions, the sintered powder or compact thereof being depleted in the silicon oxides and the corrosion resistance of the powder or compact thereof being improved thereby

CRYSTALLIZATION EXPERIMENTS ON AMORPHOUS MAGNESIUM SILICATE. II. EFFECT OF STACKING FAULTS ON INFRARED SPECTRA OF ENSTATITE

International Nuclear Information System (INIS)

Murata, K.; Chihara, H.; Koike, C.; Takakura, T.; Imai, Y.; Tsuchiyama, A.; Noguchi, T.

2009-01-01

We carried out experiments of low-temperature infrared spectroscopy and transmission electron microscopy of enstatite (MgSiO 3 ) synthesized by heating of amorphous magnesium silicate. There is a discrepancy between the infrared feature of enstatite obtained in this experiment and that of fine powdered single crystals. This reflects stacking disorder of enstatite. We show that circumstellar dust emission of enstatite is similar to the infrared feature measured in this experiment. This result strongly suggests that circumstellar enstatite has abundant stacking faults and is different from the single crystal.

Multi-Layered Effects of Fe on EMI Shielding of Sn-Al Hotel Architectural Powder

Directory of Open Access Journals (Sweden)

Hung Fei-Shuo

2016-01-01

Full Text Available No evident effect in shielding efficiency is observed when the electromagnetic wave-absorbing coating materials were applied in single layers because of the dispersing nature of the powder. When increased to two-layer coating, shielding effects were evident at both high and low frequencies, with greater shielding efficiency at low frequencies over high frequencies. It is worth noting that when increased to three-layer coating, as the weight percentage of powdered Fe increased from 5% to 8% , the shielding efficiency of the powdered-Fe composite material was raised to −35 dB This shows that, as the weight percentage gets higher, the powder shows the resonance phenomenon of permeability spectrum, and at high frequencies, the electromagnetic wave shielding efficiency of the composite materials were greatly increased. As the weight percentage of the powered Fe were increased to 8% , we were unable to spread the powder evenly in the epoxy because of the dispersing characteristic in the electromagnetic properties of Fe and the anisotropic and heterogeneous nature of a powered composite material. During production, the powder aggregates often resulted in greater heterogeneity in the materials and consequently, lowered shielding efficiency at 3GHz.

Infrared Irradiation: Toward Green Chemistry, a Review

Directory of Open Access Journals (Sweden)

René Escobedo

2016-03-01

Full Text Available This review provides a comprehensive overview of where infrared irradiation has been employed, mainly as regards activating green mode for natural products extractions, as well as to favor a reaction, highlighting its actual importance. It is also underlined that infrared irradiation heating has been around for a long time; however, only in the last eighteen years have many of its advantages been applied to satisfy a wide range of chemical processes, natural products extractions, and for the promotion of many kinds of reactions. In addition, it is brought to light that near infrared irradiation is more efficient than middle and far infrared irradiations, being easily controllable and with the quality of a fast responding heat source. Thus, the main objective of this review is to offer infrared irradiation as an alternative clean energy source to activate reactions, in addition to favor the selective extraction of natural products, all of which is within the Green Chemistry protocol. Some recent results from our laboratory are also included.

Synthesis and optical properties of Mg-Al layered double hydroxides precursor powders

Directory of Open Access Journals (Sweden)

Chia-Hsuan Lin

2017-12-01

Full Text Available The synthesis and optical properties of Mg-Al layered double hydroxide (LDH precursor powders were investigated using X-ray diffraction (XRD, Fourier transform-infrared (FT-IR spectroscopy, transmission electron microscopy (TEM, selected area electron diffraction (SAED, high-resolution TEM (HRTEM, UV-transmission spectrometer, and fluorescence spectrophotometer. The FT-IR results show that the intense absorption at around 1363–1377 cm-1 can be assigned to the antisymmetric ν3 mode of interlayer carbonate anions because the LDH phase contains some CO32-. The XRD results show that all of the Mg-Al LDH precursor powders contain only a single phase of [Mg0.833Al0.167(OH2](CO30.083·(H2O0.75 but have broad and weak intensities of peaks. All of Mg-Al LDHs precursor powders before calcination have the same photoluminescence (PL spectra. Moreover, these spectra were excited at λex = 235 nm, and the broad emission band was in the range 325-650 nm. In the range, there were relatively strong intensity at around 360, 407 and 510 nm, respectively.

Light extinction in metallic powder beds: Correlation with powder structure

International Nuclear Information System (INIS)

Rombouts, M.; Froyen, L.; Gusarov, A.V.; Bentefour, E.H.; Glorieux, C.

2005-01-01

A theoretical correlation between the effective extinction coefficient, the specific surface area, and the chord length distribution of powder beds is verified experimentally. The investigated powder beds consist of metallic particles of several tens of microns. The effective extinction coefficients are measured by a light-transmission technique at a wavelength of 540 nm. The powder structure is characterized by a quantitative image analysis of powder bed cross sections resulting in two-point correlation functions and chord length distributions. The specific surface area of the powders is estimated by laser-diffraction particle-size analysis and by the two-point correlation function. The theoretically predicted tendency of increasing extinction coefficient with specific surface area per unit void volume is confirmed by the experiments. However, a significant quantitative discrepancy is found for several powders. No clear correlation of the extinction coefficient with the powder material and particle size, and morphology is revealed, which is in line with the assumption of geometrical optics

Identification, classification, and discrimination of agave syrups from natural sweeteners by infrared spectroscopy and HPAEC-PAD.

Science.gov (United States)

Mellado-Mojica, Erika; López, Mercedes G

2015-01-15

Agave syrups are gaining popularity as new natural sweeteners. Identification, classification and discrimination by infrared spectroscopy coupled to chemometrics (NIR-MIR-SIMCA-PCA) and HPAEC-PAD of agave syrups from natural sweeteners were achieved. MIR-SIMCA-PCA allowed us to classify the natural sweeteners according to their natural source. Natural syrups exhibited differences in the MIR spectra region 1500-900 cm(-1). The agave syrups displayed strong absorption in the MIR spectra region 1061-1,063 cm(-1), in agreement with their high fructose content. Additionally, MIR-SIMCA-PCA allowed us to differentiate among syrups from different Agave species (Agavetequilana and Agavesalmiana). Thin-layer chromatography and HPAEC-PAD revealed glucose, fructose, and sucrose as the principal carbohydrates in all of the syrups. Oligosaccharide profiles showed that A. tequilana syrups are mainly composed of fructose (>60%) and fructooligosaccharides, while A. salmiana syrups contain more sucrose (28-32%). We conclude that MIR-SIMCA-PCA and HPAEC-PAD can be used to unequivocally identify and classified agave syrups. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Surface analysis by Fourier-transform infrared (FTIR) spectroscopy

International Nuclear Information System (INIS)

Powell, G.L.; Smyrl, N.R.; Fuller, E.L.

1981-01-01

A diffuse-reflectance capability for the Fourier transform infrared spectrometer at the Y-12 Plant Laboratory has been implemented. A sample cell with a 25 to 400 0 C temperature-controlled sample stage and an ultrahigh-vacuum-to-atmospheric pressure gas-handling capability has been developed. Absorbance of light from the spectrometer beam, resulting from the beam being scattered from a powder sample, can be measured. This capability of detecting molecular species on and in powders is to be used to study chemisorption on actinide and rare-earth metals, alloys, and compounds. Cell design is described along with experiments demonstrating its performance in detecting moisture absorption on uranium oxide, moisture and carbon dioxide absorption on the lithium hydride/hydroxide system, and carbon dioxide absorption on potassium borohydride. 13 figures

Identifying the hazard characteristics of powder byproducts generated from semiconductor fabrication processes.

Science.gov (United States)

Choi, Kwang-Min; An, Hee-Chul; Kim, Kwan-Sick

2015-01-01

Semiconductor manufacturing processes generate powder particles as byproducts which potentially could affect workers' health. The chemical composition, size, shape, and crystal structure of these powder particles were investigated by scanning electron microscopy equipped with an energy dispersive spectrometer, Fourier transform infrared spectrometry, and X-ray diffractometry. The powders generated in diffusion and chemical mechanical polishing processes were amorphous silica. The particles in the chemical vapor deposition (CVD) and etch processes were TiO(2) and Al(2)O(3), and Al(2)O(3) particles, respectively. As for metallization, WO(3), TiO(2), and Al(2)O(3) particles were generated from equipment used for tungsten and barrier metal (TiN) operations. In photolithography, the size and shape of the powder particles showed 1-10 μm and were of spherical shape. In addition, the powders generated from high-current and medium-current processes for ion implantation included arsenic (As), whereas the high-energy process did not include As. For all samples collected using a personal air sampler during preventive maintenance of process equipment, the mass concentrations of total airborne particles were particles less than 10 μm in diameter) using direct-reading aerosol monitor by area sampling were between 0.00 and 0.02 μg/m(3). Although the exposure concentration of airborne particles during preventive maintenance is extremely low, it is necessary to make continuous improvements to the process and work environment, because the influence of chronic low-level exposure cannot be excluded.

Analysis of Chuanxiong Rhizoma and its active components by Fourier transform infrared spectroscopy combined with two-dimensional correlation infrared spectroscopy.

Science.gov (United States)

Guo, Yizhen; Lv, Beiran; Wang, Jingjuan; Liu, Yang; Sun, Suqin; Xiao, Yao; Lu, Lina; Xiang, Li; Yang, Yanfang; Qu, Lei; Meng, Qinghong

2016-01-15

As complicated mixture systems, active components of Chuanxiong Rhizoma are very difficult to identify and discriminate. In this paper, the macroscopic IR fingerprint method including Fourier transform infrared spectroscopy (FT-IR), the second derivative infrared spectroscopy (SD-IR) and two-dimensional correlation infrared spectroscopy (2DCOS-IR), was applied to study and identify Chuanxiong raw materials and its different segmented production of HPD-100 macroporous resin. Chuanxiong Rhizoma is rich in sucrose. In the FT-IR spectra, water eluate is more similar to sucrose than the powder and the decoction. Their second derivative spectra amplified the differences and revealed the potentially characteristic IR absorption bands and combined with the correlation coefficient, concluding that 50% ethanol eluate had more ligustilide than other eluates. Finally, it can be found from 2DCOS-IR spectra that proteins were extracted by ethanol from Chuanxiong decoction by HPD-100 macroporous resin. It was demonstrated that the above three-step infrared spectroscopy could be applicable for quick, non-destructive and effective analysis and identification of very complicated and similar mixture systems of traditional Chinese medicines. Copyright © 2015 Elsevier B.V. All rights reserved.

New Strategies for Powder Compaction in Powder-based Rapid Prototyping Techniques

NARCIS (Netherlands)

Budding, A.; Vaneker, Thomas H.J.

2013-01-01

In powder-based rapid prototyping techniques, powder compaction is used to create thin layers of fine powder that are locally bonded. By stacking these layers of locally bonded material, an object is made. The compaction of thin layers of powder mater ials is of interest for a wide range of

Aluminum powder metallurgy processing

Energy Technology Data Exchange (ETDEWEB)

Flumerfelt, J.F.

1999-02-12

The objective of this dissertation is to explore the hypothesis that there is a strong linkage between gas atomization processing conditions, as-atomized aluminum powder characteristics, and the consolidation methodology required to make components from aluminum powder. The hypothesis was tested with pure aluminum powders produced by commercial air atomization, commercial inert gas atomization, and gas atomization reaction synthesis (GARS). A comparison of the GARS aluminum powders with the commercial aluminum powders showed the former to exhibit superior powder characteristics. The powders were compared in terms of size and shape, bulk chemistry, surface oxide chemistry and structure, and oxide film thickness. Minimum explosive concentration measurements assessed the dependence of explosibility hazard on surface area, oxide film thickness, and gas atomization processing conditions. The GARS aluminum powders were exposed to different relative humidity levels, demonstrating the effect of atmospheric conditions on post-atomization processing conditions. The GARS aluminum powders were exposed to different relative humidity levels, demonstrating the effect of atmospheric conditions on post-atomization oxidation of aluminum powder. An Al-Ti-Y GARS alloy exposed in ambient air at different temperatures revealed the effect of reactive alloy elements on post-atomization powder oxidation. The pure aluminum powders were consolidated by two different routes, a conventional consolidation process for fabricating aerospace components with aluminum powder and a proposed alternative. The consolidation procedures were compared by evaluating the consolidated microstructures and the corresponding mechanical properties. A low temperature solid state sintering experiment demonstrated that tap densified GARS aluminum powders can form sintering necks between contacting powder particles, unlike the total resistance to sintering of commercial air atomization aluminum powder.

Study of airborne particle generated by free falling powder

International Nuclear Information System (INIS)

Jacquelin, M.

2007-10-01

This study comes within the general framework of industrial facilities' safety research. Indeed, industrial processes, notably in the nuclear field, handle hazardous materials in powder form and can produce large quantities of fugitive dust. The study of the particles resuspension from powders is of interest of first order in order to estimate the consequences of this source term of contamination on the operator, the neighbouring installations and, if necessary, the environment. Up to now, there are very few reliable data in the scientific literature on the particulate emission in case of a scenario with an accidental free fall spill of powder. The powder dustiness evaluation is carried out using coefficients obtained in experiments, or using empirical correlations. The objective of the present work is to study the influence of some parameters involved in the airborne particles production by a free fall of powder. For that purpose, experiments are carried out in order to study the influence of parameters such as the type of discharge, the powder nature, the type of surface on which occurs the powder impaction, the system diameter used for discharge, and the falling mass. The results of mass fractions and number concentrations obtained highlighted the dominating parameters according to the type of discharge employed. Thereafter, the comparisons between our results and the empirical correlations available in the literature showed that those led to an undervaluation of the powder dustiness. This thus led us to develop, starting from the whole of experimental data, empirical correlations taking into account the various parameters studied as well as the interactions. (author)

The infrared variability and nature of symbiotic stars

International Nuclear Information System (INIS)

Feast, M.W.; Catchpole, R.M.; Whitelock, P.A.; Carter, B.S.; Roberts, G.

1983-01-01

Infrared variability and spectra show that the symbiotic systems (He 2-106, He 2-38, He 2-34) contain Mira variable components. The first two also show a longer term infrared variability. It is suggested that this is due to variable dust obscuration (as in R Aqr). The phenomenon is then too frequent for the dust clouds to be confined to the orbital planes of the binary systems. Seven Miras in symbiotics have known periods which range from 370 to 580 days, suggesting a greater frequency of long-period Miras in symbiotics than in the general field. Symbiotic Miras have dust excesses with colour temperatures near 1000 K. Observations of four other symbiotic systems (Pe 2-3, He 2-87, H 2-5, AG Peg) are consistent with their containing non-variable or low amplitude M-type components. (author)

Infrared variability and nature of symbiotic stars

Energy Technology Data Exchange (ETDEWEB)

Feast, M W; Robertson, B S.C.; Catchpole, R M [Royal Observatory, Cape Town (South Africa)

1977-05-01

Most symbiotic stars may be placed in one of two classes according to their infrared colours. In one group the systems contain an M type giant. In the other there is evidence for a star plus infrared emission from dust. JHKL photometry is given for three members of each class. Photometry of the VV Cephei system FR Sct is also given. No evidence for variability was found for systems without dust. The three systems with dust (RX Pup, RR Tel and PK 280-2/sup 0/.1) each show large variations of the stellar component (..delta..J, 1sup(m).6 to 2sup(m).7). It is concluded that these dusty systems contain Mira variables. For the systems without dust the mass transfer in the system is presumably through the inner Lagrangian point. For systems containing Miras it is possible that the companion accretes matter from a general stellar wind. Symbiotic systems containing Mira variables have more dust than average Mira variables. Either an unusually dense stellar wind is needed to produce a symbiotic system or such a system produces dust, perhaps in a high-density region resulting from the interaction of the stellar wind with the companion.

COMPARATIVE EFFICACY OF Acorus calamus POWDER AND ...

African Journals Online (AJOL)

The efficacy of the powder of a natural plant product (Acorus calamus L.) and two synthetic insecticides (i.e. Pirimiphos methyl and Rotenone) was compared in the laboratory for the control Sitophilus oryzea (L), Rhizopertha dominica (F) and Tribolium castaneum (Herbst) in stored wheat grains. Seven concentrations of the ...

Thermal and structural study of guava (Psidium guajava L powders obtained by two dehydration methods

Directory of Open Access Journals (Sweden)

Coralia Osorio

2011-01-01

Full Text Available Two food products (powders were obtained by hot-air drying or lyophilisation methods on the whole guava fruits. The powders were characterised by sensory and thermal analyses (TGA-DSC, infrared spectroscopy (IR, X-ray diffraction (XRD and scanning electron microscopy (SEM. Thermal, morphological and structural characterisations showed a similar behaviour for the two solids. TGA-DSC and IR showed the presence of pectin as the main constituent of solids. A semi-crystalline profile was evidenced by XRD, and lamellar/spherical morphologies were observed by SEM. Sensory analyses revealed an aroma highly related to guava. These value-added food products are an alternative to process guava and avoid loss during postharvest handling.

Graft copolymerization of N-vinyl-2-pyrrolidone onto pre-irradiated poly(vinylidene fluoride) powder

International Nuclear Information System (INIS)

Xu Chenqi; Huang Wei; Zhou Yongfeng; Yan Deyue; Chen Shutao; Huang Hua

2012-01-01

Graft copolymerization of N-vinyl-2-pyrrolidone (NVP) onto 60 Co γ-ray pre-irradiated poly (vinylidene fluoride) (PVDF) powder was investigated to find out the relationship between the degree of grafting (DG) and various factors, including monomer concentration, irradiation dose, reaction time, catalyst and so on. The DG can be calculated by comparing the amount of nitrogen element in the resulting copolymer (PVDF-g-PVP) powder with that in PVP on the basis of element analysis. The presence of PVP in the resulting PVDF powder was confirmed by the comparative studies of pristine PVDF and grafted PVDF powder through Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR), X-ray photoelectron spectroscopy (XPS), thermo gravimetric analyzer (TGA) and differential scanning calorimetry (DSC), respectively. When the reaction was performed at the monomer concentration of 20% (vol.) and the absorbed dose of 40 kGy for 3 h in water, the max. DG of 17.7% was obtained. - Highlights: ► We modify pristine PVDF powders with NVP by the pre-irradiated graft polymerization. ► The various factors influencing the degree of grafting are investigated in detail. ► The optimal condition of graft polymerization is obtained. ► The polymerization is processed at 20% (vol.) of NVP and 40kGy for 3 hours in water. ► The maximum degree of grafting is 17.7 % at such a condition.

Innovative technologies for powder metallurgy-based disk superalloys: Progress and proposal

Science.gov (United States)

Chong-Lin, Jia; Chang-Chun, Ge; Qing-Zhi, Yan

2016-02-01

Powder metallurgy (PM) superalloys are an important class of high temperature structural materials, key to the rotating components of aero engines. In the purview of the present challenges associated with PM superalloys, two novel approaches namely, powder preparation and the innovative spray-forming technique (for making turbine disk) are proposed and studied. Subsequently, advanced technologies like electrode-induction-melting gas atomization (EIGA), and spark-plasma discharge spheroidization (SPDS) are introduced, for ceramic-free superalloy powders. Presently, new processing routes are sought after for preparing finer and cleaner raw powders for disk superalloys. The progress of research in spray-formed PM superalloys is first summarized in detail. The spray-formed superalloy disks specifically exhibit excellent mechanical properties. This paper reviews the recent progress in innovative technologies for PM superalloys, with an emphasis on new ideas and approaches, central to the innovation driving techniques like powder processing and spray forming. Project supported by the National Natural Science Foundation of China (Grant Nos. 50974016 and 50071014).

Environmental impact analysis of batik natural dyes using life cycle assessment

Science.gov (United States)

Rinawati, Dyah Ika; Sari, Diana Puspita; Purwanggono, Bambang; Hermawan, Andy Tri

2017-11-01

The use of natural dyes for batik dyeing is fewer than synthetic dyes because of its limitations in the application such complexity in manufacture and usage. For ease of use, natural dyes need to be processed into instant products. Extract of natural dyes are generally produced in liquid form that are less practical in long-term use. Dye powder obtained by drying the liquid extract using spray dryer. Production process of liquid natural dye is simpler and require less energy but need more energy for transporting. It is important to know which type of natural dyes should be produced based on their environmental impact. This research aim to compare environmental impact between liquid and powder natural dyes and also to find relative contribution of different stage in life cycle to total environmental impact. The appropriate method to analyze and compare the environmental impacts of powder and liquid natural dyes is Life Cycle Assessment (LCA). The "cradle to grave" approach used to assess environmental impact of powder and liquid natural dyes of Jalawe rind throughout production process of natural dyes, distribution and use of natural dyes for coloring batik. Results of this research show that powder natural dyes has lower environmental impacts than liquid natural dyes. It was found that distribution, mordanting and packaging of liquid dyes have big contribution to environmental impact.

Effects of hydrolysis on solid-state relaxation and stickiness behavior of sodium caseinate-lactose powders.

Science.gov (United States)

Mounsey, J S; Hogan, S A; Murray, B A; O'Callaghan, D J

2012-05-01

Hydrolyzed or nonhydrolyzed sodium caseinate-lactose dispersions were spray dried, at a protein: lactose ratio of 0.5, to examine the effects of protein hydrolysis on relaxation behavior and stickiness of model powders. Sodium caseinate (NC) used included a nonhydrolyzed control (DH 0) and 2 hydrolyzed variants (DH 8.3 and DH 15), where DH = degree of hydrolysis (%). Prior to spray drying, apparent viscosities of liquid feeds (at 70°C) at a shear rate of 20/s were 37.6, 3.14, and 3.19 mPa·s, respectively, for DH 0, DH 8, and DH 15 dispersions. Powders containing hydrolyzed casein were more susceptible to sticking than those containing intact NC. The former had also lower bulk densities and powder particle sizes. Scanning electron microscopy showed that hydrolyzed powders had thinner particle walls and were more friable than powders containing intact NC. Secondary structure of caseinates, determined by Fourier transform infrared spectroscopy, was affected by the relative humidity of storage and the presence of lactose as co-solvent rather than its physical state. Glass transition temperatures and lactose crystallization temperatures, determined by differential scanning calorimetry were not affected by caseinate hydrolysis, although the effects of protein hydrolysis on glass-rubber transitions (T(gr)) could be determined by thermo-mechanical analysis. Powders containing hydrolyzed NC had lower T(gr) values (~30°C) following storage at a higher subcrystallization relative humidity (33%) compared with powder with nonhydrolyzed NC (T(gr) value of ~40°C), an effect that reflects more extensive plasticization of powder matrices by moisture. Results support that sodium caseinate-lactose interactions were weak but that relaxation behavior, as determined by the susceptibility of powder to sticking, was affected by hydrolysis of sodium caseinate. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

The effect of storage on the colour of paprika powders with added oleoresin

Directory of Open Access Journals (Sweden)

Horváth Zs. H.

2016-12-01

Full Text Available The use of natural food colours is preferred to that of arti­ficial dyestuffs for modern alimentary purposes. Paprika is a spice plant grown and consumed in considerable quantities worldwide and also used as a natural food colour, so the colouring power of powders is very important. The colour of paprika powder is highly relevant too because the consumer concludes its colouring power based on its colour. The colouring power of paprika powders is directly determined by the quality and quantity of the colouring agent of paprika. The paprika oleoresin, that is an oil soluble extract from the fruits of Capsicum Annum Linn or Capsicum Frutescens, is suitable to raise the colour agent content of paprika powders. We investigated how the colour and the characteristics of paprika powder samples with added oleoresin change in the course of storage. The colour agent content of 7 different quality powders was increased with 7-75% using oleoresin. The initial colour agent content of samples changed between 41 and 169 ASTA units. The powders were made from Chinese, Peruvian, and Hungarian paprika. Colour measurements were performed with a HunterLab MiniScan colour-measuring instrument. The CIELab colour system was used for colour characterization. The colour agent content and the colour coordinates of samples were measured throughout 9 months. The decrease of colour agent con­tent varied between 22 and 51 percent, while the average reduction was 33 percent. The quantity of added oleoresin did not influence the colour agent content decrease significantly.

Synthesis of alumina powder with seeds by Pechini Method using O2 as calcination atmosphere

International Nuclear Information System (INIS)

Salem, R.E.P.; Guilherme, K.A.; Chinelatto, A.S.A.; Chinelatto, A. L.

2012-01-01

Alumina is a very investigated material due to its excellent refractory characteristics and mechanical properties. Its alpha phase, the most stable one, has a formation temperature of about 1200 ° C. Due to its high temperature of formation, many researches have been trying to reduce it through addition of seeds of alpha phase in chemical processes of synthesis. This work aims to synthesize ultrafine powders of alpha-alumina by the Pechini method with seeding, and using an O 2 atmosphere in the pre-calcination (500 ° C) and calcination (1000 ° C and 1100° C) steps. The resulting powders were characterized through X-ray diffractometry, infrared spectroscopy and scanning electron microscopy. The results were compared with samples calcined on ai. It was verified that the presence of oxygen in the calcination atmosphere favored the elimination of residual carbon from the precursor powders, forthcoming from the great amount of organic material used on the synthesis, modifying its morphology and favoring reduction of particle size. (author)

Optimization of process parameters in precipitation for consistent quality UO2 powder production

International Nuclear Information System (INIS)

Tiwari, S.K.; Reddy, A.L.V.; Venkataswamy, J.; Misra, M.; Setty, D.S.; Sheela, S.; Saibaba, N.

2013-01-01

Nuclear reactor grade natural uranium dioxide powder is being produced through precipitation route, which is further processed before converting into sintered pellets used in the fabrication of PHWR fuel assemblies of 220 and 540 MWe type reactors. The process of precipitating Uranyl Nitrate Pure Solution (UNPS) is an important step in the UO 2 powder production line, where in soluble uranium is transformed into solid form of Ammonium Uranate (AU), which in turn reflects and decides the powder characteristics. Precipitation of UNPS with vapour ammonia is being carried out in semi batch process and process parameters like ammonia flow rate, temperature, concentration of UNPS and free acidity of UNPS are very critical and decides the UO 2 powder quality. Variation in these critical parameters influences powder characteristics, which in turn influences the sinterability of UO 2 powder. In order to get consistent powder quality and sinterability the critical parameter like ammonia flow rate during precipitation is studied, optimized and validated. The critical process parameters are controlled through PLC based automated on-line data acquisition systems for achieving consistent powder quality with increased recovery and production. The present paper covers optimization of process parameters and powder characteristics. (author)

Geochemistry of inorganic nitrogen in waters released from coal-bed natural gas production wells in the Powder River Basin, Wyoming

Science.gov (United States)

Smith, Richard L.; Repert, Deborah A.; Hart, Charles P.

2009-01-01

Water originating from coal-bed natural gas (CBNG) production wells typically contains ammonium and is often disposed via discharge to ephemeral channels. A study conducted in the Powder River Basin, Wyoming, documented downstream changes in CBNG water composition, emphasizing nitrogen-cycling processes and the fate of ammonium. Dissolved ammonium concentrations from 19 CBNG discharge points ranged from 95 to 527 μM. Within specific channels, ammonium concentrations decreased with transport distance, with subsequent increases in nitrite and nitrate concentrations. Removal efficiency, or uptake, of total dissolved inorganic nitrogen (DIN) varied between channel types. DIN uptake was greater in the gentle-sloped, vegetated channel as compared to the incised, steep, and sparsely vegetated channel and was highly correlated with diel patterns of incident light and dissolved oxygen concentration. In a larger main channel with multiple discharge inputs (n = 13), DIN concentrations were >300 μM, with pH > 8.5, after 5 km of transport. Ammonium represented 25−30% of the large-channel DIN, and ammonium concentrations remained relatively constant with time, with only a weak diel pattern evident. In July 2003, the average daily large-channel DIN load was 23 kg N day−1entering the Powder River, an amount which substantially increased the total Powder River DIN load after the channel confluence. These results suggest that CBNG discharge may be an important source of DIN to western watersheds, at least at certain times of the year, and that net oxidation and/or removal is dependent upon the extent of contact with sediment and biomass, type of drainage channel, and time of day.

Infrared Astronomy and Star Formation

International Nuclear Information System (INIS)

Evans, N.J.

1985-01-01

Infrared astronomy is a natural tool to use in studying star formation because infrared light penetrates the surrounding dust and because protostars are expected to emit infrared light. Infrared mapping and photometry have revealed many compact sources, often embedded in more extensive warm dust associated with a molecular cloud core. More detailed study of these objects is now beginning, and traditional interpretations are being questioned. Some compact sources are now thought to be density enhancements which are not self-luminous. Infrared excesses around young stars may not always be caused by circumstellar dust; speckle measurements have shown that at least some of the excess toward T Tauri is caused by an infrared companion. Spectroscopic studies of the dense, star-forming cores and of the compact objects themselves have uncovered a wealth of new phenomena, including the widespread occurence of energetic outflows. New discoveries with IRAS and with other planned infrared telescopes will continue to advance this field. (author)

Physico-chemical properties and solubility behaviour of multi-substituted hydroxyapatite powders containing silicon

International Nuclear Information System (INIS)

Sprio, S.; Tampieri, A.; Landi, E.; Sandri, M.; Martorana, S.; Celotti, G.; Logroscino, G.

2008-01-01

Hydroxyapatite powders characterized by ionic substitutions both in anionic and cationic sites were successfully prepared by synthesis in aqueous medium. The process parameters were set up to allow the simultaneous substitution of the foreign ions, namely carbonate, magnesium and silicon in the crystallographic site of calcium and phosphorus, keeping in count the competition which arises between atoms destined to occupy the same crystallographic site. The chemico-physical properties of the powders were investigated through several analytical techniques, i.e. X-ray diffraction, infrared spectroscopy, atomic emission spectroscopy and thermo-gravimetric analysis. The results show that the utilization of sodium hydrogen-carbonate as a reactant allows the entering of carbonate into the HA structure, mainly in phosphate position, while sodium is eliminated during the process of the powder washing. The entering of silicon in the HA structure progressively reduces its crystallinity, as also carbonate ions do. Silicate and carbonate ions can enter simultaneously into the HA structure, in biological-like amounts, although they compete for the occupation of the phosphate site; the powder crystallinity is strongly reduced as the content of the two substituting ions increases, so that a limit molar concentration exists where the apatite structure collapses and an amorphous phase forms with the simultaneous formation of crystalline calcium carbonate. Solubility tests, carried out at physiological conditions, reveal an increased calcium release in the HA powders containing silicon compared to the silicon-free HA; the solubility behaviour of the multi-substituted HA powders at physiological conditions makes these materials promising as bioactive bone scaffold, as they are able to continuously supply ions which are essential for the process of bone reconstruction

Natural zeolite reactivity towards ozone: the role of compensating cations.

Science.gov (United States)

Valdés, Héctor; Alejandro, Serguei; Zaror, Claudio A

2012-08-15

Among indoor pollutants, ozone is recognised to pose a threat to human health. Recently, low cost natural zeolites have been applied as alternative materials for ozone abatement. In this work, the effect of compensating cation content of natural zeolite on ozone removal is studied. A Chilean natural zeolite is used here as starting material. The amount of compensating cations in the zeolite framework was modified by ion exchange using an ammonium sulphate solution (0.1 mol L(-1)). Characterisation of natural and modified zeolites were performed by X-ray powder diffraction (XRD), nitrogen adsorption at 77K, elemental analysis, X-ray fluorescence (XRF), thermogravimetric analysis coupled with mass spectroscopy (TGA-MS), and temperature-programmed desorption of ammonia (NH(3)-TPD). Ozone adsorption and/or decomposition on natural and modified zeolites were studied by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Results show that the zeolite compensating cation content affects ozone interaction with zeolite active sites. Ammonium ion-exchange treatments followed by thermal out-gassing at 823 K, reduces ozone diffusion resistance inside the zeolite framework, increasing ozone abatement on zeolite surface active sites. Weak and strong Lewis acid sites of zeolite surface are identified here as the main active sites responsible of ozone removal. Copyright © 2012 Elsevier B.V. All rights reserved.

Microstructure, optimum pigment content and low infrared emissivity of polyurethane/Ag composite coatings

International Nuclear Information System (INIS)

Zhang, Weigang; Xu, Guoyue; Ding, Ruya; Qiao, Jialiang; Duan, Kaige

2013-01-01

Polyurethane (PU)/Ag composite coatings with low infrared emissivity were successfully prepared by using PU and flaky Ag powders as adhesives and pigments, respectively. The infrared emissivity and microstructure of as-prepared products were systematically investigated by infrared emissometer and scanning electron microscopy, respectively. Infrared emissivity measurement shows that the emissivity of the coatings approaches the lowest value of 0.082 at the wavelength of 8–14 µm when the Ag content is about 20 wt%. Microstructure observation shows that the coatings have similar one-dimensional photonic structural characteristics. According to the structural characteristics, a simulation method for optimum pigment content and the cause of low infrared emissivity of the coatings were successfully obtained and discussed by using the theories of one-dimensional photonic structure, respectively. The results indicate that the low infrared emissivity of PU/Ag composite coatings is derived from the similar one-dimensional photonic structure in the coatings, and the calculated optimum Ag content is in good agreement with the experimental value, which reveals that it is a practical simulation method for optimum pigment content of low infrared emissivity composite coatings

Spherical rhenium metal powder

International Nuclear Information System (INIS)

Leonhardt, T.; Moore, N.; Hamister, M.

2001-01-01

The development of a high-density, spherical rhenium powder (SReP) possessing excellent flow characteristics has enabled the use of advanced processing techniques for the manufacture of rhenium components. The techniques that were investigated were vacuum plasma spraying (VPS), direct-hot isostatic pressing (D-HIP), and various other traditional powder metallurgy processing methods of forming rhenium powder into near-net shaped components. The principal disadvantages of standard rhenium metal powder (RMP) for advanced consolidation applications include: poor flow characteristics; high oxygen content; and low and varying packing densities. SReP will lower costs, reduce processing times, and improve yields when manufacturing powder metallurgy rhenium components. The results of the powder characterization of spherical rhenium powder and the consolidation of the SReP are further discussed. (author)

Thermally induced phase transformation of pearl powder

International Nuclear Information System (INIS)

Zhang, Guoqing; Guo, Yili; Ao, Ju; Yang, Jing; Lv, Guanglie; Shih, Kaimin

2013-01-01

The polymorphic phase transformation of thermally treated pearl powder was investigated by X-ray diffraction and thermoanalytical techniques. The phase transformation was based on quantification of the calcite content at various temperatures using Rietveld refinement analysis. The results show that the phase transformation of pearl aragonite occurred within a temperature range of 360–410 °C, which is 50–100 °C lower than the range for non-biomineralized aragonite. These thermoanalytical results suggest that the phase transformation of pearl aragonite may occur immediately after the thermal decomposition of the organic matrix in the pearl powder. An important finding is that decomposition of the organic matrix may greatly facilitate such transformation by releasing additional space for an easier structural reconstruction during the phase transformation process. - Highlights: ► Providing a new method to describe the polymorphic transition of pearl powder ► The phase transition sketch was exhibited by XRD phase quantitative analysis. ► There are dozens of degrees in advance comparing to natural aragonite. ► The phase transition occurs following the thermal decomposition of organism

Measurement of loose powder density

International Nuclear Information System (INIS)

Akhtar, S.; Ali, A.; Haider, A.; Farooque, M.

2011-01-01

Powder metallurgy is a conventional technique for making engineering articles from powders. Main objective is to produce final products with the highest possible uniform density, which depends on the initial loose powder characteristics. Producing, handling, characterizing and compacting materials in loose powder form are part of the manufacturing processes. Density of loose metallic or ceramic powder is an important parameter for die design. Loose powder density is required for calculating the exact mass of powder to fill the die cavity for producing intended green density of the powder compact. To fulfill this requirement of powder metallurgical processing, a loose powder density meter as per ASTM standards is designed and fabricated for measurement of density. The density of free flowing metallic powders can be determined using Hall flow meter funnel and density cup of 25 cm/sup 3/ volume. Density of metal powders like cobalt, manganese, spherical bronze and pure iron is measured and results are obtained with 99.9% accuracy. (author)

Hazardous Waste Water Remediation by Ecoresin-Dry Cow Dung Powder

Science.gov (United States)

Bagla, Hemlata; Barot, Nisha

2013-04-01

Water, the matter, matrix, medium and the mother of our life, is indeed one of the drivers of Nature. Through water cycle only the intra and inter equilibrium is maintained constantly between entire 'green' and 'blue'. Unfortunately, with each successive epoch of industrialization and urbanization, human societies have produced non-biodegradable waste hulk with far beyond handling capacities of mankind. At this juncture the very need is to appreciate and move towards the cost as well as time effective scientific alternatives for the removal of aqueous heavy metal pollutants. Green chemistry advocates the utilization of naturally available bio-resins which are environmentally benign alternative to current synthetic materials and technologies employed for waste water treatment. This explicit investigation aims to explore Dry Cow dung powder, DCP, a natural biosorbent as a green and clean alternative for the aqueous waste water treatment. It is naturally available bio-organic, complex, polymorphic humified fecal matter of cow and is enriched with minerals, carbohydrates, fats, proteins, bile pigments, aliphatic - aromatic species such as 'Humic acid'(HA). The HA has been successfully extracted by authors from DCP and this piece of work has been published in the International Journal [1]. We have developed simple, efficient and eco-friendly method for the removal of aqueous heavy metal pollutant such as Cr(VI) [2], Cd(II), Cr(III) [3] and Hg(II) as well radiotoxic 90Sr(II) [4], employing DCP. DCP is employed without any pre or post treatment. Being freely and easily available DCP has an edge over processed natural adsorbent considering their cost, time and energy efficiency. In nutshell we have to remember that prevention is better than the cure. If we fail to meet this, the situation will surely augment which will drain our water, our life, to slaughters knife..! Reference: 1. H.K.Bagla, N.S.Barot, Soil Amendement by Green Supplement: Dry Cowdung powder, EGUGA - 11

Pyrotechnic countermeasures: II. Advanced aerial infrared countermeasures

Energy Technology Data Exchange (ETDEWEB)

Koch, Ernst-Christian [Diehl BGT Defence GmbH and Co. KG, Fischbachstrasse 16, D-90552 Roethenbach a. d. Pegnitz (Germany)

2006-02-15

This paper discusses the technology of advanced aerial infrared countermeasures and related work disclosed in the unclassified literature. Missile-seeker head counter-countermeasures include spectral discrimination, kinematical discrimination, rise-time discrimination, UV/VIS discrimination and area temperature matching. Advanced flare payloads designed to counter dual color seekers contain selectively emitting compositions based primarily on high carbon fuels and perchlorates. Other advanced payloads consist of low temperature emitters like pyrophoric metal foils and gasless pyrotechnic compositions like Fe/KClO{sub 4}. The optimization of black body flares, still considered essential to a successful countermeasure solution, make use of new fuels based on e.g. meta-stable alloys and nanometer-sized powders as well as high energetic oxidizers. Kinematic flares today use combined propellant and infrared grains. 116 references from the public domain are given. For part I see Propellants, Explos., Pyrotech. 2001, 26, 3. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

An Investigation on Self-Compacting Concrete Using Ultrafine Natural Steatite Powder as Replacement to Cement

Directory of Open Access Journals (Sweden)

P. Kumar

2017-01-01

Full Text Available An experimental investigation was made on flow properties and compressive strength of self-compacting concrete (SCC with ultrafine natural steatite powder (UFNSP as replacement to cement. The tests were conducted on specimens with 5%, 10%, 15%, 20%, and 25% of replacement of UFNSP to the weight of cement and compared to the control specimens. The flow properties of all specimens were tested and checked for their limit with the existing guidelines. The compressive strength test was done on all specimens for strength of 7 days, 14 days, 28 days, and 56 days. The hardened samples were tested for their microstructural behavior and the elements Mg, Ca, and Si were mapped. Through mapping, the formations of M-S-H along with C-S-H are observed. The results show that the addition of UFNSP influences the flow property, by reducing the flow, and increases the compressive strength till 20% replacement. Further the addition of UFNSP increases the denseness of microstructure of the specimens thus resulting in the strength increment.

Quantifying low amorphous or crystalline amounts of alpha-lactose-monohydrate using X-ray powder diffraction, near-infrared spectroscopy, and differential scanning calorimetry.

Science.gov (United States)

Fix, I; Steffens, K J

2004-05-01

Efficient and accurate quantification of low amorphous and crystalline contents within pharmaceutical materials still remains a challenging task in the pharmaceutical industry. Since X-ray powder diffraction (XRPD) equipment has improved in recent years, our aim was 1) to investigate the possibility of substantially lowering the detection limits of amorphous or crystalline material to about 1% or 0.5% w/w respectively by applying conventional Bragg Brentano optics, combined with a fast and simple evaluation technique; 2) to perform these measurements within a short time to make it suitable for routine analysis; and 3) to subject the same data sets to a partial least squares regression (PLSR) in order to investigate whether it is possible to improve accuracy and precision compared to the standard integration method. Near-infrared spectroscopy (NIRS) and differential scanning calorimetry (DSC) were chosen as reference method. As model substance, alpha lactose monohydrate was chosen to create calibration curves based on predetermined mixtures of highly crystalline and amorphous substance. In contrast to DSC, XRPD and NIRS revealed an excellent linearity, precision, and accuracy with the percent of crystalline amount and a detectability down to about 0.5% w/w. Chemometric evaluation (partial least squares regression) applied to the XRPD data further improved the quality of our calibration.

Fundamentals of powder metallurgy

International Nuclear Information System (INIS)

Khan, I.H.; Qureshi, K.A.; Minhas, J.I.

1988-01-01

This book is being presented to introduce the fundamentals of technology of powder metallurgy. An attempt has been made to present an overall view of powder metallurgy technology in the first chapter, whereas chapter 2 to 8 deal with the production of metal powders. The basic commercial methods of powder production are briefly described with illustrations. Chapter 9 to 12 describes briefly metal powder characteristics and principles of testing, mixing, blending, conditioning, compaction and sintering. (orig./A.B.)

Low temperature synthesis of nano alpha-alumina powder by two-step hydrolysis

International Nuclear Information System (INIS)

Yan, Ting; Guo, Xiaode; Zhang, Xiang; Wang, Zhixiang; Shi, Jinqiu

2016-01-01

Highlights: • The nano α-Al 2 O 3 with good dispersion was prepared by two-step hydrolysis. • α-Al 2 O 3 powders were added as seed particles in the hydrolysis. • This article indicated that the glucose could impel the γ-Al 2 O 3 transformed to α-Al 2 O 3 directly. • This article indicated that the addictive of α-Al 2 O 3 seed could improve the phase transformation rate of γ-Al 2 O 3 to α-Al 2 O 3 . • In this article, the pure α-Al 2 O 3 could be obtained by calcining at 1000 °C for 1.5 h. - Abstract: The ultral fine alpha-alumina powder has been successfully synthesized via two-step hydrolysis of aluminum isopropoxide. Glucose and polyvinyl pyrrolidone were used as surfactants during the appropriate processing step. The alpha-alumina powder was used as seed particles. Several synthesis parameters, such as the amount of seeds, surfactants, and calcination temperature, were studied by X-ray diffraction (XRD), Fourier transform infrared spectra (FTIR), Thermogravimetry-differential scanning calorimetry (TG-DSC), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The experimental results showed that glucose greatly lower the phase transformation temperature of alpha-alumina by impelling the gamma-alumina transformed to alpha-alumina directly, and the seed could improve the phase transformation rate of alpha-alumina, the polyvinylpyrrolidone have an effect on preventing excessive grain growth and agglomeration of alpha-alumina powder. Comparatively well dispersed alpha-alumina powder with particle size less than 50 nm can be synthesized through this method after calcinations at 1000 °C for 2 h.

(TECTONA GRANDIS LEAF POWDER

Directory of Open Access Journals (Sweden)

Yash Mishra

2015-01-01

Full Text Available In this study, the adsorption potential of Teak (Tectona grandis leaf powder (TLP toremove Methylene blue (MB and Malachite Green (MG dye molecules from aqueoussolution was investigated. Batch experiments were conducted to evaluate the influenceof operational parameters such as, pH (2−9, adsorbent dosage (1−7 g/L, contact time(15−150 minutes and initial dye concentration (20−120 mg/L at stirring speed of 150rpm for the adsorption of MB and MG on TLP. Maximum removal efficiency of 98.4%and 95.1% was achieved for MB and MG dye, respectively. The experimentalequilibrium data were analysed using Langmuir, Freundlich and Temkin isothermmodels and it was found that, it fitted well to the Freundlich isotherm model. Thesurface structure and morphology of the adsorbent was characterized using scanningelectron microscopy (SEM and the presence of functional groups and its interactionwith the dye molecules were analysed using Fourier transform infrared spectroscopy(FTIR. Based on the investigation, it has been demonstrated that the teak leaf powderhas good potential for effective adsorption of methylene blue and malachite green dye.

Low pressure powder injection moulding of stainless steel powders

Energy Technology Data Exchange (ETDEWEB)

Zampieron, J.V.; Soares, J.P.; Mathias, F.; Rossi, J.L. [Powder Processing Center CCP, Inst. de Pesquisas Energeticas e Nucleares, Sao Paulo, SP (Brazil); Filho, F.A. [IPEN, Inst. de Pesquisas Energeticas e Nucleares, Cidade Univ., Sao Paulo, SP (Brazil)

2001-07-01

Low-pressure powder injection moulding was used to obtain AISI 316L stainless steel parts. A rheological study was undertaken using gas-atomised powders and binders. The binders used were based on carnauba wax, paraffin, low density polyethylene and microcrystalline wax. The metal powders were characterised in terms of morphology, particle size distribution and specific surface area. These results were correlated to the rheological behaviour. The mixture was injected in the shape of square bar specimens to evaluate the performance of the injection process in the green state, and after sintering. The parameters such as injection pressure, viscosity and temperature were analysed for process optimisation. The binders were thermally removed in low vacuum with the assistance of alumina powders. Debinding and sintering were performed in a single step. This procedure shortened considerably the debinding and sintering time. (orig.)

Infrared Radiation and Blackbody Radiation

OpenAIRE

2005-01-01

tut present graph Tutorial Presentation Graph Interactive Media Element This interactive tutorial covers the following: How infrared radiation was discovered., The regions of infrared radiation and their relations to temperature., The nature of blackbody radiation and Planck's radiation law., The relationship between temperature and the power emitted by radiation.The interactions in this tutorial include clicking to reveal new information, and questions that help students...

Surface design of powder by precise modification; Kotai hyomen no seimitsuna kaishitsu seigyo

Energy Technology Data Exchange (ETDEWEB)

Chikazawa, Masatoshi

1999-01-01

The progress of the recent technology is it in high performance, the one manufactured by development of the high function material. It is skillful, and the nature of this effective material is greatly influenced by the various materialities of the raw material powder and a function again. Therefore, the moment it diversifies all the more from now on, a demand for the raw material powder is thought to become more precise control than the thing of the materiality of the powder and the function. Precise quality function technology on the surface of the powder which should make the materiality of the purpose and a functional expression possible is very important to meet such a requirement. Quality silica powder is used as the sample, and you must investigate about the micro-mechanism of the water control by effective based quality of surface from such a position. (NEDO)

An amorphous Si-O film tribo-induced by natural hydrosilicate powders on ferrous surface

International Nuclear Information System (INIS)

Zhang, Baosen; Xu, Binshi; Xu, Yi; Ba, Zhixin; Wang, Zhangzhong

2013-01-01

The tribological properties of surface-coated serpentine powders suspended in oil were evaluated using an Optimal SRV-IV oscillating friction and wear tester. The worn surface and the tribo-induced protective film were characterized by scanning electron microscope and focused ion beam (SEM/FIB) work station, energy dispersive spectroscopy (EDS) and transmission electron microscope (TEM). Results indicate that with 0.5 wt% addition of serpentine powders to oil, the friction coefficient and wear rate significantly decrease referenced to those of the base oil alone. An amorphous SiO x film with amorphous SiO x particles inserted has formed on the worn surface undergoing the interactions between serpentine particles and friction surfaces. The protective film with excellent lubricating ability and mechanical properties is responsible for the reduced friction and wear.

Assessment of radiation hazard indices arising from natural radionuclides content of powdered milk in Malaysia

International Nuclear Information System (INIS)

Priharti, W.; Samat, S.B.; Yasir, M.S.; Garba, N.N.

2016-01-01

The activity concentration of 226 Ra, 232 Th and 40 K were determined by gamma spectrometry in twenty-six different brands of powdered milk available in Malaysia. The measured activity concentration was then used to estimate the radiation hazard indices in term of ingestion dose and cancer risk. The total ingestion dose was found to range between 35.19 and 461.72 μSv y -1 and the estimated cancer risk for adult is 1.23 x 10 -4 . These results were found to be below the internationally recommended level. This indicates that the powdered milk in Malaysia would not pose any significant radiological impact to the population. (author)

Foundations of powder metallurgy

International Nuclear Information System (INIS)

Libenson, G.A.

1987-01-01

Consideration is being given to physicochemical foundations and technology of metal powders, moulding and sintering of bars, made of them or their mixtures with nonmetal powders. Data on he design of basic equipment used in the processes of powder metallurgy and its servicing are presented. General requirements of safety engineering when fabricating metal powders and products of them are mentioned

Infrared spectroscopy of molecular submonolayers on surfaces by infrared scanning tunneling microscopy: tetramantane on Au111.

Science.gov (United States)

Pechenezhskiy, Ivan V; Hong, Xiaoping; Nguyen, Giang D; Dahl, Jeremy E P; Carlson, Robert M K; Wang, Feng; Crommie, Michael F

2013-09-20

We have developed a new scanning-tunneling-microscopy-based spectroscopy technique to characterize infrared (IR) absorption of submonolayers of molecules on conducting crystals. The technique employs a scanning tunneling microscope as a precise detector to measure the expansion of a molecule-decorated crystal that is irradiated by IR light from a tunable laser source. Using this technique, we obtain the IR absorption spectra of [121]tetramantane and [123]tetramantane on Au(111). Significant differences between the IR spectra for these two isomers show the power of this new technique to differentiate chemical structures even when single-molecule-resolved scanning tunneling microscopy (STM) images look quite similar. Furthermore, the new technique was found to yield significantly better spectral resolution than STM-based inelastic electron tunneling spectroscopy, and to allow determination of optical absorption cross sections. Compared to IR spectroscopy of bulk tetramantane powders, infrared scanning tunneling microscopy (IRSTM) spectra reveal narrower and blueshifted vibrational peaks for an ordered tetramantane adlayer. Differences between bulk and surface tetramantane vibrational spectra are explained via molecule-molecule interactions.

Copper removal using bio-inspired polydopamine coated natural zeolites

Energy Technology Data Exchange (ETDEWEB)

Yu, Yang; Shapter, Joseph G. [Flinders Centre for Nanoscale Science and Technology, School of Chemical and Physical Sciences, Flinders University, Sturt Road, Bedford Park, Adelaide 5042, SA (Australia); Popelka-Filcoff, Rachel [School of Chemical and Physical Sciences, Flinders University, Sturt Road, Bedford Park, Adelaide 5042, SA (Australia); Bennett, John W. [Centre for Nuclear Applications, Australian Nuclear Science and Technology Organisation, Lucas Heights 2234, NSW (Australia); Ellis, Amanda V., E-mail: Amanda.Ellis@flinders.edu.au [Flinders Centre for Nanoscale Science and Technology, School of Chemical and Physical Sciences, Flinders University, Sturt Road, Bedford Park, Adelaide 5042, SA (Australia)

2014-05-01

Highlights: • Natural zeolites were modified with bio-inspired polydopamine. • A 91.4% increase in Cu(II) ion adsorption capacity was observed. • Atomic absorption and neutron activation analysis gave corroborative results. • Neutron activation analysis was used to provide accurate information on 30+ elements. • Approximately 90% of the adsorbed copper could be recovered by 0.1 M HCl treatment. - Abstract: Herein, for the first time, natural clinoptilolite-rich zeolite powders modified with a bio-inspired adhesive, polydopamine (PDA), have been systematically studied as an adsorbent for copper cations (Cu(II)) from aqueous solution. Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) revealed successful grafting of PDA onto the zeolite surface. The effects of pH (2–5.5), PDA treatment time (3–24 h), contact time (0 to 24 h) and initial Cu(II) ion concentrations (1 to 500 mg dm{sup −3}) on the adsorption of Cu(II) ions were studied using atomic absorption spectroscopy (AAS) and neutron activation analysis (NAA). The adsorption behavior was fitted to a Langmuir isotherm and shown to follow a pseudo-second-order reaction model. The maximum adsorption capacities of Cu(II) were shown to be 14.93 mg g{sup −1} for pristine natural zeolite and 28.58 mg g{sup −1} for PDA treated zeolite powders. This impressive 91.4% increase in Cu(II) ion adsorption capacity is attributed to the chelating ability of the PDA on the zeolite surface. Furthermore studies of recyclability using NAA showed that over 50% of the adsorbed copper could be removed in mild concentrations (0.01 M or 0.1 M) of either acid or base.

Copper removal using bio-inspired polydopamine coated natural zeolites

International Nuclear Information System (INIS)

Yu, Yang; Shapter, Joseph G.; Popelka-Filcoff, Rachel; Bennett, John W.; Ellis, Amanda V.

2014-01-01

Highlights: • Natural zeolites were modified with bio-inspired polydopamine. • A 91.4% increase in Cu(II) ion adsorption capacity was observed. • Atomic absorption and neutron activation analysis gave corroborative results. • Neutron activation analysis was used to provide accurate information on 30+ elements. • Approximately 90% of the adsorbed copper could be recovered by 0.1 M HCl treatment. - Abstract: Herein, for the first time, natural clinoptilolite-rich zeolite powders modified with a bio-inspired adhesive, polydopamine (PDA), have been systematically studied as an adsorbent for copper cations (Cu(II)) from aqueous solution. Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) revealed successful grafting of PDA onto the zeolite surface. The effects of pH (2–5.5), PDA treatment time (3–24 h), contact time (0 to 24 h) and initial Cu(II) ion concentrations (1 to 500 mg dm −3 ) on the adsorption of Cu(II) ions were studied using atomic absorption spectroscopy (AAS) and neutron activation analysis (NAA). The adsorption behavior was fitted to a Langmuir isotherm and shown to follow a pseudo-second-order reaction model. The maximum adsorption capacities of Cu(II) were shown to be 14.93 mg g −1 for pristine natural zeolite and 28.58 mg g −1 for PDA treated zeolite powders. This impressive 91.4% increase in Cu(II) ion adsorption capacity is attributed to the chelating ability of the PDA on the zeolite surface. Furthermore studies of recyclability using NAA showed that over 50% of the adsorbed copper could be removed in mild concentrations (0.01 M or 0.1 M) of either acid or base

Fourier transform infrared spectroscopy of peptides.

Science.gov (United States)

Bakshi, Kunal; Liyanage, Mangala R; Volkin, David B; Middaugh, C Russell

2014-01-01

Fourier transform infrared (FTIR) spectroscopy provides data that are widely used for secondary structure characterization of peptides. A wide array of available sampling methods permits structural analysis of peptides in diverse environments such as aqueous solution (including optically turbid media), powders, detergent micelles, and lipid bilayers. In some cases, side chain vibrations can also be resolved and used for tertiary structure and chemical analysis. Data from several low-resolution spectroscopic techniques, including FTIR, can be combined to generate an empirical phase diagram, an overall picture of peptide structure as a function of environmental conditions that can aid in the global interpretation of large amounts of spectroscopic data.

Production of rare earth polishing powders in Russia

International Nuclear Information System (INIS)

Kosynkin, V.D.; Ivanov, E.N.; Kotrekhov, V.A.; Shtutza, M.G.; Grabko, A.I.

1998-01-01

in a suspension; polishing powder Ftoropol with addition of fluorine and higher contents of cerium dioxide (at least 70% by mass) that has a higher polishing ability and is attrition-proof, used for high-speed treatment of optical lenses, mirrors, TV screens and eyeglasses. The rare earth polishing powders made in Russia possess the following physico-chemical properties and performance characteristics; cerium dioxide content in solid REE solution - 50-90% by mass; F-ion content (in Ftoropol powder) - 8-14% by mass; non-REE content of sodium, calcium, strontium and iron impurities - at most 0.1% by mass of each element; natural radionuclide content of thorium, uranium, actinium, potassium-40 series, total standard specific activity - 0.45-0.85 Bq/g; - average particle size, 2.0-3.5 μm; density - 6.3-6.8 g/cm 3 ; pH of aqueous extract, 6-7; sedimentary stability - 10-20 minutes; polishing ability - 45-60 mg per 31 minutes (for polishing resin); abrasive inclusions - none. The report gives analysis of the. Russian powders compared against the best world analogues such as Cerox (Rhone Poulenc Company, France), Regipol (London and Scandinavian Division Chemical Company, England), etc. The analysis results imply, that the chief characteristics (granulometric composition, polishing ability and service life) of the Russian samples do not yield to the best foreign analogues, and in some properties (radionuclide content, sedimentary stability and scratching inclusions quantity) even surpass them

Use of whey powder and skim milk powder for the production of fermented cream

Directory of Open Access Journals (Sweden)

Ceren AKAL

2016-01-01

Full Text Available Abstract This study is about the production of fermented cream samples having 18% fat by addition of starter cultures. In order to partialy increase non-fat solid content of fermented cream samples, skim milk powder and demineralized whey powder in two different rates (50% and 70% were used. Samples were analyzed for changes in their biochemical and physicochemical properties (total solid, ash, fat, titratable acidity, pH value, total nitrogen, viscosity, tyrosine, acid number, peroxide and diacetyl values during 29-day of storage period. Samples tested consisted of 7 different groups; control group (without adding any powder, skim milk powder, 50% demineralized whey powder and 70% demineralized whey powder samples were in two different addition rate (2% and 4%. Also samples were analyzed for sensory properties. According to the results obtained, the addition of milk powder products affected titratable acidity and tyrosine values of fermented cream samples. Although powder addition and/or storage period didn’t cause significant variations in total solid, ash, fat, pH value, viscosity, acid number, peroxide, tyrosine and diacetyl values; sensory properties of fermented cream samples were influenced by both powder addition and storage period. Fermented cream containing 2% skim milk powder gets the top score of sensory evaluation among the samples.

In-line and Real-time Monitoring of Resonant Acoustic Mixing by Near-infrared Spectroscopy Combined with Chemometric Technology for Process Analytical Technology Applications in Pharmaceutical Powder Blending Systems.

Science.gov (United States)

Tanaka, Ryoma; Takahashi, Naoyuki; Nakamura, Yasuaki; Hattori, Yusuke; Ashizawa, Kazuhide; Otsuka, Makoto

2017-01-01

Resonant acoustic ® mixing (RAM) technology is a system that performs high-speed mixing by vibration through the control of acceleration and frequency. In recent years, real-time process monitoring and prediction has become of increasing interest, and process analytical technology (PAT) systems will be increasingly introduced into actual manufacturing processes. This study examined the application of PAT with the combination of RAM, near-infrared spectroscopy, and chemometric technology as a set of PAT tools for introduction into actual pharmaceutical powder blending processes. Content uniformity was based on a robust partial least squares regression (PLSR) model constructed to manage the RAM configuration parameters and the changing concentration of the components. As a result, real-time monitoring may be possible and could be successfully demonstrated for in-line real-time prediction of active pharmaceutical ingredients and other additives using chemometric technology. This system is expected to be applicable to the RAM method for the risk management of quality.

Optimization of process parameters in precipitation for consistent quality UO{sub 2} powder production

Energy Technology Data Exchange (ETDEWEB)

Tiwari, S.K.; Reddy, A.L.V.; Venkataswamy, J.; Misra, M.; Setty, D.S.; Sheela, S.; Saibaba, N., E-mail: misra@nfc.gov.in [Nuclear Fuel Complex, Hyderabad (India)

2013-07-01

Nuclear reactor grade natural uranium dioxide powder is being produced through precipitation route, which is further processed before converting into sintered pellets used in the fabrication of PHWR fuel assemblies of 220 and 540 MWe type reactors. The process of precipitating Uranyl Nitrate Pure Solution (UNPS) is an important step in the UO{sub 2} powder production line, where in soluble uranium is transformed into solid form of Ammonium Uranate (AU), which in turn reflects and decides the powder characteristics. Precipitation of UNPS with vapour ammonia is being carried out in semi batch process and process parameters like ammonia flow rate, temperature, concentration of UNPS and free acidity of UNPS are very critical and decides the UO{sub 2} powder quality. Variation in these critical parameters influences powder characteristics, which in turn influences the sinterability of UO{sub 2} powder. In order to get consistent powder quality and sinterability the critical parameter like ammonia flow rate during precipitation is studied, optimized and validated. The critical process parameters are controlled through PLC based automated on-line data acquisition systems for achieving consistent powder quality with increased recovery and production. The present paper covers optimization of process parameters and powder characteristics. (author)

Synthesis of nano-sized amorphous boron powders through active dilution self-propagating high-temperature synthesis method

Energy Technology Data Exchange (ETDEWEB)

Wang, Jilin [The State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Gu, Yunle [School of Material Science and Engineering, Wuhan Institute of Technology, Wuhan 430073 (China); Li, Zili [The State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Wang, Weimin, E-mail: wangwm@hotmail.com [The State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Fu, Zhengyi [The State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China)

2013-06-01

Graphical abstract: Nano-sized amorphous boron powders were synthesized by active dilution self-propagating high-temperature synthesis (SHS) method. The effects of endothermic reaction rate, the possible chemical reaction mechanism and active dilution model for synthesis of the product were also discussed. Highlights: ► Nano-sized amorphous boron powders were synthesized by active dilution self-propagating high-temperature synthesis method. ► The morphology, particle size and purity of the samples could be effectively controlled via changing the endothermic rate. ► The diluter KBH{sub 4} played an important role in active dilution synthesis of amorphous nano-sized boron powders. ► The active dilution method could be further popularized and become a common approach to prepare various inorganic materials. - Abstract: Nano-sized amorphous boron powders were synthesized by active dilution self-propagating high-temperature synthesis (SHS) method at temperatures ranging from 700 °C to 850 °C in a SHS furnace using Mg, B{sub 2}O{sub 3} and KBH{sub 4} as raw materials. Samples were characterized by X-ray powder diffraction (XRD), Laser particle size analyzer, Fourier transform infrared spectra (FTIR), X-ray energy dispersive spectroscopy (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution transmission TEM (HRTEM). The boron powders demonstrated an average particle size of 50 nm with a purity of 95.64 wt.%. The diluter KBH{sub 4} played an important role in the active dilution synthesis of amorphous nano-sized boron powders. The effects of endothermic reaction rate, the possible chemical reaction mechanism and active dilution model for synthesis of the product were also discussed.

Synthesis of nano-sized amorphous boron powders through active dilution self-propagating high-temperature synthesis method

International Nuclear Information System (INIS)

Wang, Jilin; Gu, Yunle; Li, Zili; Wang, Weimin; Fu, Zhengyi

2013-01-01

Graphical abstract: Nano-sized amorphous boron powders were synthesized by active dilution self-propagating high-temperature synthesis (SHS) method. The effects of endothermic reaction rate, the possible chemical reaction mechanism and active dilution model for synthesis of the product were also discussed. Highlights: ► Nano-sized amorphous boron powders were synthesized by active dilution self-propagating high-temperature synthesis method. ► The morphology, particle size and purity of the samples could be effectively controlled via changing the endothermic rate. ► The diluter KBH 4 played an important role in active dilution synthesis of amorphous nano-sized boron powders. ► The active dilution method could be further popularized and become a common approach to prepare various inorganic materials. - Abstract: Nano-sized amorphous boron powders were synthesized by active dilution self-propagating high-temperature synthesis (SHS) method at temperatures ranging from 700 °C to 850 °C in a SHS furnace using Mg, B 2 O 3 and KBH 4 as raw materials. Samples were characterized by X-ray powder diffraction (XRD), Laser particle size analyzer, Fourier transform infrared spectra (FTIR), X-ray energy dispersive spectroscopy (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution transmission TEM (HRTEM). The boron powders demonstrated an average particle size of 50 nm with a purity of 95.64 wt.%. The diluter KBH 4 played an important role in the active dilution synthesis of amorphous nano-sized boron powders. The effects of endothermic reaction rate, the possible chemical reaction mechanism and active dilution model for synthesis of the product were also discussed

21 CFR 520.1696a - Buffered penicillin powder, penicillin powder with buffered aqueous diluent.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Buffered penicillin powder, penicillin powder with... FORM NEW ANIMAL DRUGS § 520.1696a Buffered penicillin powder, penicillin powder with buffered aqueous diluent. (a) Specifications. When reconstituted, each milliliter contains penicillin G procaine equivalent...

Influence of Powder Injection Parameters in High-Pressure Cold Spray

Science.gov (United States)

Ozdemir, Ozan C.; Widener, Christian A.

2017-10-01

High-pressure cold spray systems are becoming widely accepted for use in the structural repair of surface defects of expensive machinery parts used in industrial and military equipment. The deposition quality of cold spray repairs is typically validated using coupon testing and through destructive analysis of mock-ups or first articles for a defined set of parameters. In order to provide a reliable repair, it is important to not only maintain the same processing parameters, but also to have optimum fixed parameters, such as the particle injection location. This study is intended to provide insight into the sensitivity of the way that the powder is injected upstream of supersonic nozzles in high-pressure cold spray systems and the effects of variations in injection parameters on the nature of the powder particle kinetics. Experimentally validated three-dimensional computational fluid dynamics (3D CFD) models are implemented to study the particle impact conditions for varying powder feeder tube size, powder feeder tube axial misalignment, and radial powder feeder injection location on the particle velocity and the deposition shape of aluminum alloy 6061. Outputs of the models are statistically analyzed to explore the shape of the spray plume distribution and resulting coating buildup.

Biaxially textured articles formed by powder metallurgy

Science.gov (United States)

Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

2003-08-05

A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of ternary mixtures consisting of: Ni powder, Cu powder, and Al powder, Ni powder, Cr powder, and Al powder; Ni powder, W powder and Al powder; Ni powder, V powder, and Al powder; Ni powder, Mo powder, and Al powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100} orientation texture; and further having a Curie temperature less than that of pure Ni.

The incorporation of exhauster powder mass in ceramics atomised

International Nuclear Information System (INIS)

Knop, W.R.; Valentina, L. Dalla; Folgueiras, M.V.; Semptikovski, S.C.

2009-01-01

Inside the context of alternative search for the use of industrial waste as natural raw for the industrial ceramic, this work had the objective to evaluate the possibility of the use of exhauster powder generated in the foundry process. The characterization was performed by scanning electron microscopy, x-ray diffractometry and thermal analysis, noting that it is a powder with a high content of fine and compatible with the composition of ceramic bodies. Formulations were prepared with different exhauster powder content. The sintered materials at 1000, 1100 and 1200 deg C were characterized according technological properties as water absorption, linear shrinkage, bulk density and apparent density. Microstructural analysis was carried out by scanning electron microscopy and X-ray diffraction. The results showed that it is possible to use the waste. It was observed that the waste increase the density in sintering process, and with high levels of waste occurs an increase of the porosity and intensification in the color of the new material. (author)

Low-temperature synthesis of silicon carbide powder using shungite

International Nuclear Information System (INIS)

Gubernat, A.; Pichor, W.; Lach, R.; Zientara, D.; Sitarz, M.; Springwald, M.

2017-01-01

The paper presents the results of investigation the novel and simple method of synthesis of silicon carbide. As raw material for synthesis was used shungite, natural mineral rich in carbon and silica. The synthesis of SiC is possible in relatively low temperature in range 1500–1600°C. It is worth emphasising that compared to the most popular method of SiC synthesis (Acheson method where the temperature of synthesis is about 2500°C) the proposed method is much more effective. The basic properties of products obtained from different form of shungite and in wide range of synthesis temperature were investigated. The process of silicon carbide formation was proposed and discussed. In the case of synthesis SiC from powder of raw materials the product is also in powder form and not requires any additional process (crushing, milling, etc.). Obtained products are pure and after grain classification may be used as abrasive and polishing powders. (Author)

Low-temperature synthesis of silicon carbide powder using shungite

Energy Technology Data Exchange (ETDEWEB)

Gubernat, A.; Pichor, W.; Lach, R.; Zientara, D.; Sitarz, M.; Springwald, M.

2017-07-01

The paper presents the results of investigation the novel and simple method of synthesis of silicon carbide. As raw material for synthesis was used shungite, natural mineral rich in carbon and silica. The synthesis of SiC is possible in relatively low temperature in range 1500–1600°C. It is worth emphasising that compared to the most popular method of SiC synthesis (Acheson method where the temperature of synthesis is about 2500°C) the proposed method is much more effective. The basic properties of products obtained from different form of shungite and in wide range of synthesis temperature were investigated. The process of silicon carbide formation was proposed and discussed. In the case of synthesis SiC from powder of raw materials the product is also in powder form and not requires any additional process (crushing, milling, etc.). Obtained products are pure and after grain classification may be used as abrasive and polishing powders. (Author)

Fourier–transform infrared spectroscopic characterization of natu ...

Indian Academy of Sciences (India)

We present here the characterization of the fulgurites by Fourier transform infrared (FTIR) absorption, X-ray diffraction and X-ray fluorescence methods. The amorphous nature of the substance has been confirmed by Fourier transform infrared spectra of the fulgurites, which exhibit prominent absorption band in the region ...

Nacre biomimetic design—A possible approach to prepare low infrared emissivity composite coatings

International Nuclear Information System (INIS)

Zhang, Weigang; Xu, Guoyue; Ding, Ruya; Duan, Kaige; Qiao, Jialiang

2013-01-01

Mimicking the highly organized brick-and-mortar structure of nacre, a kind of nacre-like organic–inorganic composite material of polyurethane (PU)/flaky bronze composite coatings with low infrared emissivity was successfully designed and prepared by using PU and flaky bronze powders as adhesives and pigments, respectively. The infrared emissivity and microstructure of the coatings were systematically investigated by infrared emissometer and scanning electron microscopy, respectively, and the cause of low infrared emissivity of the coatings was discussed by using the theories of one-dimensional photonic structure. The results show that the infrared emissivity of the nacre-like PU/flaky bronze composite coatings can be as low as 0.206 at the bronze content of 60 wt. %, and it is significantly lower than the value of PU/sphere bronze composite coatings. Microstructure observation illustrated that the nacre-like PU/flaky bronze composite coatings have similar one-dimensional photonic structural characteristics. The low infrared emissivity of PU/flaky bronze composite coatings is derived from the similar one-dimensional photonic structure in the coatings. Highlights: ► Nacre-like composite coatings with low infrared emissivity were prepared. ► Infrared emissivity of PU/flaky bronze composite coatings can be as low as 0.206. ► One-dimensional photonic structure is the cause for low emissivity of the coatings.

Exploitation of the residue of foundry exhauster powder in ceramics for covering

International Nuclear Information System (INIS)

Valentina, Luiz Veriano Oliveira Dalla; Folgueras, Marilena Valadares; Knop, Wanessa Rejane; Semptikovski, Simone Claudiano

2010-01-01

The work evaluates the possibility of the use the exhauster powder generated in the foundry process in ceramic mass atomized semigre type. This residue was characterized by scanning electron microscopy, x-ray diffractometry and thermal analysis (DSC, TG). Formulations were prepared with different exhauster powder content. The sintered materials between 1000°C at 1 200 deg C. The results showed of the scanning electron microscopy and the characterization of the technological properties (water absorption, linear shrinkage and apparent density) had demonstrated the viability of the use of this residue. Through experiments it was observed that the exhauster powder promoted an increment in the sintering degree, and raised texts of this they increase of the porosity and intensification in the color of the new material. That is, it is possible to incorporate small amounts of the exhauster powder in substitution the substances cousins of natural origin. (author)

The structure of betaxolol studied by infrared spectroscopy and natural bond orbital theory.

Science.gov (United States)

Canotilho, João; Castro, Ricardo A E

2010-08-01

Betaxolol is a selective beta(1) receptor blocker used in the treatment of hypertension and glaucoma. A study of the betaxolol structure based on infrared spectroscopy and natural bond orbital (NBO) theory is the main aim of the present research. FTIR spectra of the solid betaxolol were recorded in the region from 4000 to 400cm(-1), in the temperature range between 25 and -170 degrees C. For spectral interpretation, spectrum of the deuterated betaxolol and the theoretical vibrational spectra of the conformer present in the solid obtained at the B3LYP/6-31G* level of theory, were used. Further insight into the structure was provided by natural bond orbital theory. NBO analysis of the conformer, before and after optimization, was carried out at the same level of theory referred above. Vibrational modes involved in hydrogen bond in the stretching and bending region were used in the estimation of the enthalpy using empirical correlations between enthalpy and the frequency shift that occurs as a result of the establishment of intermolecular hydrogen bonds. A detailed study of the structure of betaxolol and of its intermolecular interactions was obtained from the combination spectroscopy and NBO theory. Copyright 2010 Elsevier B.V. All rights reserved.

An analysis of un-dissolved powders of instant powdered soup by using ultrasonographic image

Science.gov (United States)

Kawaai, Yukinori; Kato, Kunihito; Yamamoto, Kazuhiko; Kasamatsu, Chinatsu

2008-11-01

Nowadays, there are many instant powdered soups around us. When we make instant powdered soup, sometimes we cannot dissolve powders perfectly. Food manufacturers want to improve this problem in order to make better products. Therefore, they have to measure the state and volume of un-dissolved powders. Earlier methods for analyzing removed the un-dissolved powders from the container, the state of the un-dissolved power was changed. Our research using ultrasonographic image can measure the state of un-dissolved powders with no change by taking cross sections of the soup. We then make 3D soup model from these cross sections of soup. Therefore we can observe the inside of soup that we do not have ever seen. We construct accurate 3D model. We can visualize the state and volume of un-dissolved powders with analyzing the 3D soup models.

Rietveld analysis, powder diffraction and cement

International Nuclear Information System (INIS)

Peterson, V.

2002-01-01

Full text: Phase quantification of cement is essential in its industrial use, however many methods are inaccurate and/or time consuming. Powder diffraction is one of the more accurate techniques used for quantitative phase analysis of cement. There has been an increase in the use of Rietveld refinement and powder diffraction for the analysis and phase quantification of cement and its components in recent years. The complex nature of cement components, existence of solid solutions, polymorphic variation of phases and overlapping phase peaks in diffraction patterns makes phase quantification of cements by powder diffraction difficult. The main phase in cement is alite, a solid solution of tricalcium silicate. Tricalcium silicate has been found to exist in seven modifications in three crystal systems, including triclinic, monoclinic, and rhombohedral structures. Hence, phase quantification of cements using Rietveld methods usually involves the simultaneous modelling of several tricalcium silicate structures to fit the complex alite phase. An industry ordinary Portland cement, industry and standard clinker, and a synthetic tricalcium silicate were characterised using neutron, laboratory x-ray and synchrotron powder diffraction. Diffraction patterns were analysed using full-profile Rietveld refinement. This enabled comparison of x-ray, neutron and synchrotron data for phase quantification of the cement and examination of the tricalcium silicate. Excellent Rietveld fits were achieved, however the results showed that the quantitative phase analysis results differed for some phases in the same clinker sample between various data sources. This presentation will give a short introduction about cement components including polymorphism, followed by the presentation of some problems in phase quantification of cements and the role of Rietveld refinement in solving these problems. Copyright (2002) Australian X-ray Analytical Association Inc

The Effects of Ovine Whey Powders on Durum Wheat-Based Doughs

Directory of Open Access Journals (Sweden)

Nicola Secchi

2018-01-01

Full Text Available Two types of ovine whey powder, with different protein content, were added at increasing substitution rates to two types of semolina, one with strong and tenacious gluten and the other with weak and sticky gluten. For each dough the optimum mixing time and hydration level were calculated using the consistograph. The whey powder negatively affected the leavening volume of all doughs, at all percentages except the lowest one (5%, mainly because of its effects on the elastic component of gluten as measured with a stress relaxation test. Differences of the secondary structure of gluten proteins among samples were investigated by analyzing the amide I band in the Fourier transform infrared spectra of the dough. Weak and strong semolina showed a different relative percentage of α-helix, random coil, and β-sheet structures. The longer mixing times for dough formation when using semolina with strong gluten led to an increase in α-helices and random coils, which caused a worse leavening performance than the weak-gluten semolina.

A novel approach to determine the thermal transition of gum powder/hydro-gels using dynamic mechanical analysis

Science.gov (United States)

Nagamadhu, M.; Jeyaraj, P.; Kumar, G. C. Mohan

2018-04-01

The dynamic characterization of materials plays a major role in the present area. The many researchers are worked on solid materials and its characterization, it can be tested using dynamic mechanical analyzer (DMA), however, no such work on powder a semiliquid samples. The powder and liquid samples can also easily characterization as like solid samples using DMA. These powder samples are analyzed with a material pocket method which can be used to accurately determine very low levels of variation in powder properties, due to the high sensitivity of DMA to glass transitions. No such DMA studies on hydrogel and Gum powders. The gum powders are used in various applications start from food industries, pharmacy, natural gums paste, biomedical applications etc. among all this applications gum Ghatti is one of the powders using for varies applications. Around 50 milligrams of Ghatti powders are placed inside material pocket and analyzed storage modulus (G'), loss modulus (G″) and tan delta (δ). Also, understand the curing and glass transition effect using water, glycerin and superplastic from room temperature to 200°C. The result shows that storage modulus decreases with increase in temperature in pure Ghatti powder. The surprising improvement in storage modulus was found with an increase in temperature with addition of water, glycerin, and superplastic. However, loss modulus and tan delta are also having very significant influence and also shows a clear peak of the tan delta. The loss modulus results were found to be improved by adding solidifying agents, along with this water and superplastic better influence. But glycerine found to be hydrogel in nature and thermodynamic properties are much influenced by frequency.

Biaxially textured articles formed by powder metallurgy

Science.gov (United States)

Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

2003-07-29

A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100} orientation texture; and further having a Curie temperature less than that of pure Ni.

SEM-EDX analysis of an unknown "known" white powder found in a shipping container from Peru

Science.gov (United States)

Albright, Douglas C.

2009-05-01

In 2008, an unknown white powder was discovered spilled inside of a shipping container of whole kernel corn during an inspection by federal inspectors in the port of Baltimore, Maryland. The container was detained and quarantined while a sample of the powder was collected and sent to a federal laboratory where it was screened using chromatography for the presence of specific poisons and pesticides with negative results. Samples of the corn kernels and the white powder were forwarded to the Food and Drug Administration, Forensic Chemistry Center for further analysis. Stereoscopic Light Microscopy (SLM), Scanning Electron Microscopy/Energy Dispersive X-ray Spectrometry (SEM/EDX), and Polarized Light Microscopy/Infrared Spectroscopy (PLM-IR) were used in the analysis of the kernels and the unknown powder. Based on the unique particle analysis by SLM and SEM as well as the detection of the presence of aluminum and phosphorous by EDX, the unknown was determined to be consistent with reacted aluminum phosphide (AlP). While commonly known in the agricultural industry, aluminum phosphide is relatively unknown in the forensic community. A history of the use and acute toxicity of this compound along with some very unique SEM/EDX analysis characteristics of aluminum phosphide will be discussed.

Characterization of ceramic powder compacts

International Nuclear Information System (INIS)

Yanai, K.; Ishimoto, S.; Kubo, T.; Ito, K.; Ishikawa, T.; Hayashi, H.

1995-01-01

UO 2 and Al 2 O 3 powder packing structures in cylindrical powder compacts are observed by scanning electron microscopy using polished cross sections of compacts fixed by low viscosity epoxy resin. Hard aggregates which are not destroyed during powder compaction are observed in some of the UO 2 powder compacts. A technique to measure local density in powder compacts is developed based on counting characteristic X-ray intensity by energy dispersive X-ray analysis (EDX). The local density of the corner portion of the powder compact fabricated by double-acting dry press is higher than that of the inner portion. ((orig.))

Does a Change from Whole to Powdered Food (Artemia franciscana eggs Increase Oviposition in the Ladybird Coleomegilla maculata?

Directory of Open Access Journals (Sweden)

Eric W. Riddick

2015-09-01

Full Text Available The limited availability of alternative foods to replace natural prey hinders cost-effective mass production of ladybird beetles for augmentative biological control. We compared the effects of powdered vs. whole Artemia franciscana (A. franciscana (brine shrimp eggs with or without a dietary supplement on development and reproduction of Coleomegilla maculata (C. maculata (Coleoptera: Coccinellidae. We tested the hypotheses that (1 powdered A. franciscana eggs are more suitable than whole eggs; and (2 palmitic acid, a common fatty acid in natural prey, i.e., aphids, is an effective dietary supplement. Development time, pre-imaginal survival, sex ratio, and body weight of adults did not differ significantly amongst individuals fed powdered vs. whole eggs, with or without 5% palmitic acid. Significantly more oviposition occurred when females were fed powdered eggs than whole eggs and powdered eggs with 5% palmitic acid than whole eggs with or without 5% palmitic acid. A weak functional relationship was found between pre-oviposition time and total oviposition by females fed powdered eggs with 5% palmitic acid; pre-oviposition time decreased as oviposition increased. Food treatments had no significant differential effect on progeny (egg hatch rate. In conclusion, a simple change in A. franciscana egg texture and particle size (i.e., blending whole eggs into a dust-like powder increases oviposition in C. maculata. Supplementing powdered eggs with 5% palmitic acid might accelerate oogenesis (egg maturation in some females.

Densification behavior of aluminum alloy powder mixed with zirconia powder inclusion under cold compaction

International Nuclear Information System (INIS)

Ryu, Hyun Seok; Lee, Sung Chul; Kim, Ki Tae

2002-01-01

Densification behavior of composite powders was investigated during cold compaction. Experimental data were obtained for aluminum alloy powder mixed with zirconia powder inclusion under triaxial compression. The cap model with constraint factors was implemented into a finite element program(ABAQUS) to simulate compaction responses of composite powders during cold compaction. Finite element results were compared with experimental data for densification behavior of composite powders under cold isostatic pressing and die compaction. The agreements between experimental data and finite element calculations from the cap model with constraint factors were good

Nuclear fuel powder transfer device

International Nuclear Information System (INIS)

Komono, Akira

1998-01-01

A pair of parallel rails are laid between a receiving portion to a molding portion of a nuclear fuel powder transfer device. The rails are disposed to the upper portion of a plurality of parallel support columns at the same height. A powder container is disposed while being tilted in the inside of the vessel main body of a transfer device, and rotational shafts equipped with wheels are secured to right and left external walls. A nuclear powder to be mixed, together with additives, is supplied to the powder container of the transfer device. The transfer device engaged with the rails on the receiving side is transferred toward the molding portion. The wheels are rotated along the rails, and the rotational shafts, the vessel main body and the powder container are rotated. The nuclear powder in the tilted powder container disposed is rotated right and left and up and down by the rotation, and the powder is mixed satisfactory when it reaches the molding portion. (I.N.)

Use of Red Cactus Pear (Opuntia ficus-indica Encapsulated Powder to Pigment Extruded Cereal

Directory of Open Access Journals (Sweden)

Martha G. Ruiz-Gutiérrez

2017-01-01

Full Text Available Encapsulated powder of the red cactus pear is a potential natural dye for the food industry and a known antioxidant. Although the use of this powder is possible, it is not clear how it alters food properties, thus ensuing commercial acceptability. The aim of this study was to evaluate the effect of encapsulated powder of the red cactus pear on the physicochemical properties of extruded cereals. The powder was mixed (2.5, 5.0, and 7.5% w/w with maize grits and extruded (mix moisture 22%, temperature 100°C, and screw speed 325 rpm. The physical, chemical, and sensory characteristics of the extruded cereal were evaluated; extruded cereal without encapsulated powder was used as a control. All cereal extrudates pigmented with the encapsulated powder showed statistically significant differences (P<0.05 in expansion, water absorption, color, density, and texture compared to the control. The encapsulated powder had a positive effect on expansion and water absorption indices, as well as color parameters, but a negative effect on density and texture. Extruded cereal properties were significantly (P<0.05 correlated. Sensorially, consumers accepted the extruded cereal with a lower red cactus pear powder content (2.5% w/w, because this presented characteristics similar to extruded cereal lacking pigment.

Shewanella strain isolated from black powder

Energy Technology Data Exchange (ETDEWEB)

Lutterbach, Marcia T.S.; Contador, Luciana S.; Oliveira, Ana Lucia C.; Galvao, Mariana M. [National Institute of Technology (INT), Rio de Janeiro, RJ (Brazil); Pimenta, Gutemberg S. [PETROBRAS, Rio de Janeiro, RJ (Brazil)

2009-07-01

Black powder is a term frequently used to refer to residues formed by various types of iron sulfides mixed with contaminants eventually present in the natural gas flow. According to some researchers, the occurrence of black powder in gas pipelines, besides its chemical corrosion origin, can be directly related to the sulfate-reducing bacteria (SRB) metabolism in this environment. A black powder sample was inoculated in a Post gate E medium modified with the addition of thioglycolate. The resulting positive culture was kept in the laboratory for four years until its use. A dilution technique was then performed aiming to isolate an SRB strain. The bacterial strain isolated and identified through DNA sequencing was not an SRB but rather a Shewanella sp. Compared to the sulfate-reducing bacteria group-traditionally considered the foremost responsible for microbially-influenced corrosion (MIC) - Shewanella is a facultative anaerobe and has a versatile metabolism. Shewanella is able to reduce ferric iron and sulfite, oxidize hydrogen gas, and produce hydrogen sulfide; therefore, these bacteria can be responsible for MIC and pit formation. The isolated Shewanella was used in a corrosion experiment, and the corrosion products were characterized by X-ray diffraction, identifying iron sulfides, iron oxides, and sulfur. Our results indicate that the strain isolated, S. putrefaciens, plays a key role in corrosion problems in gas pipelines. (author)

Eggshell Powder as an Adsorbent for Removal of Fluoride from Aqueous Solution: Equilibrium, Kinetic and Thermodynamic Studies

Directory of Open Access Journals (Sweden)

R. Bhaumik

2012-01-01

Full Text Available A new medium, eggshell powder has been developed for fluoride removal from aqueous solution. Fluoride adsorption was studied in a batch system where adsorption was found to be pH dependent with maximum removal efficiency at 6.0. The experimental data was more satisfactorily fitted with Langmuir isotherm model. The kinetics and the factor controlling adsorption process fully accepted by pseudo-second-order model were also discussed. Ea was found to be 45.98 kJmol-1 by using Arrhenius equation, indicating chemisorption nature of fluoride onto eggshell powder. Thermodynamic study showed spontaneous nature and feasibility of the adsorption process with negative enthalpy (∆H0 value also supported the exothermic nature. Batch experiments were performed to study the applicability of the adsorbent by using fluoride contaminated water collected from affected areas. These results indicate that eggshell powder can be used as an effective, low-cost adsorbent to remove fluoride from aqueous solution as well as groundwater.

Characterization of cubic ceria?zirconia powders by X-ray diffraction and vibrational and electronic spectroscopy

Science.gov (United States)

Sánchez Escribano, Vicente; Fernández López, Enrique; Panizza, Marta; Resini, Carlo; Gallardo Amores, José Manuel; Busca, Guido

2003-10-01

The X-ray diffraction (XRD) patterns and the Infrared, Raman and UV-visible spectra of CeO 2ZrO 2 powders prepared by co-precipitation are presented. Raman spectra provide evidence for the largely predominant cubic structure of the powders with CeO 2 molar composition higher than 25%. Also skeletal IR spectra allow to distinguish cubic from tetragonal phases which are instead not easily distinguished on the basis of the XRD patterns. All mixed oxides including pure ceria are strong UV absorbers although also absorb in the violet visible region. By carefully selecting their composition and treatment temperature, the onset of the radiation that they cut off can be chosen in the 425-475 nm interval. Although they are likely metastable, the cubic phases are still pure even after heating at 1173 K for 4 h.

Effect of γ-irradiation on the physical and mechanical properties of chitosan powder

International Nuclear Information System (INIS)

Zainol, Ismail; Akil, Hazizan Md; Mastor, Azreena

2009-01-01

In this study, locally produced chitosan powder was irradiated with pre-determined doses of γ-ray (Co-60) of 10 kGy, 25 kGy, 50 kGy and 100 kGy respectively. The properties of both chitosan powder and the chitosan film were examined and compared with unradiated chitosan. Physical characteristic of the irradiated powder and film was studied using stereo microscope. It was observed that the γ-ray induces a noticeable colour tone intensity change to the chitosan. Further investigation using Fourier Transformed Infrared Spectroscopy (FT-IR) analysis has confirmed that the chain scission reaction was occurred as a result of γ-ray exposure through the depolymerization mechanisms. Interestingly, the degree of deacetylation (DD) of chitosan measured using FT-IR showed a negligible effect due to the exposure of γ-ray radiation. Further investigation on the viscosity average molecular weight (M v ) showed a reduction of M v from 577 kD of pure chitosan to 458 kD, 242 kD, 159 kD and 106 kD for 10 kGy, 25 kGy, 50 kGy and 100 kGy of γ-radiated chitosan respectively. In addition, the tensile strength and elongation at break showed a similar decreasing trend with increasing dosage of γ-ray

Application of laser in powder metallurgy

International Nuclear Information System (INIS)

Tolochko, N.K.

1995-01-01

Modern status of works in the field of laser application in powder metallurgy (powders preparation, sintering, coatings formation, powder materials processing) is considered. The attention is paid to the new promising direction in powder products shape-formation technology - laser layer-by-layer selective powders sintering and bulk sintering of packaged layered profiles produced by laser cutting of powder-based sheet blanks. 67 refs

Headspace analysis gas-phase infrared spectroscopy: a study of xanthate decomposition on mineral surfaces

Science.gov (United States)

Vreugdenhil, Andrew J.; Brienne, Stephane H. R.; Markwell, Ross D.; Butler, Ian S.; Finch, James A.

1997-03-01

The O-ethyldithiocarbonate (ethyl xanthate, CH 3CH 2OCS -2) anion is a widely used reagent in mineral processing for the separation of sulphide minerals by froth flotation. Ethyl xanthate interacts with mineral powders to produce a hydrophobic layer on the mineral surface. A novel infrared technique, headspace analysis gas-phase infrared spectroscopy (HAGIS) has been used to study the in situ thermal decomposition products of ethyl xanthate on mineral surfaces. These products include CS 2, COS, CO 2, CH 4, SO 2, and higher molecular weight alkyl-containing species. Decomposition pathways have been proposed with some information determined from 2H- and 13C-isotope labelling experiments.

Preparation of Nd-doped gadolinium-gallium garnet laser ceramic powder by sol-gel method

Institute of Scientific and Technical Information of China (English)

YAO Yan-ping; LIU Jing-he

2006-01-01

Preparation of Nd3+:Gd3Ga5O12 polycrystalline material by sol-gel method was preparated in this paper.The structure and the pattern of the sample were analyzed by thermogravimetric analysis and differential thermal analysis(TG-DTA),Infrared spectrum,XRD,TEM and electron spectrum,which indicated that the powder with good characteristics of 70-100 nm can be obtained by sintering at 1 000℃.It was shown that the chemical composition of the sample was agreed with experimental requirements by electron spectrum analysis.

Random laser action in stoichiometric Nd3Ga5O12 garnet crystal powder

International Nuclear Information System (INIS)

Iparraguirre, I; Azkargorta, J; Barredo-Zuriarrain, M; Balda, R; Fernández, J; Kamada, K; Yoshikawa, A; Rodríguez-Mendoza, U R; Lavín, V

2016-01-01

This work explores the room temperature infrared random laser (RL) performance of Nd 3+ ions in a new stoichiometric Nd 3 Ga 5 O 12 crystal powder. The time-resolved measurements show that the RL pulse is able to follow the subnanosecond oscillations of the pump pulse profile. The pump threshold energy and the absolute stimulated emission energy have been measured using a method developed by the authors. The laser slope efficiency is the highest compared to other Nd 3+ stoichiometric RL crystals. (letter)

NiTiO3 powders obtained by polymeric precursor method: Synthesis and characterization

International Nuclear Information System (INIS)

Lopes, K.P.; Cavalcante, L.S.; Simoes, A.Z.; Varela, J.A.; Longo, E.; Leite, E.R.

2009-01-01

Nickel titanate (NiTiO 3 ) powders were synthesized by the polymeric precursor method after thermal treatment at different temperatures for 2 h in air atmosphere. The decomposition of the precursors was monitored by differential scanning calorimetry and thermogravimetric analysis. The NiTiO 3 powders presented a reduction in the specific surface area and increase of the average particle size with the evolution of the temperature. The structural evolution of NiTiO 3 phase was accompanied by X-ray diffraction and Fourier transform Raman spectroscopy. By scanning electron microscopy was revealed the agglomerated nature of very fine particles of NiTiO 3 powders annealed from 600 to 1000 deg. C

The use of gamma irradiation in preparation of polybutadiene rubber nanopowder; Its effect on particle size, morphology and crosslink structure of the powder

Science.gov (United States)

Rezaei Abadchi, Majid; Jalali-Arani, Azam

2014-02-01

The aim of this work was the preparation and characterization of polybutadiene rubber (BR) powder by irradiating of rubber lattices using 60Co radiation and spray-drying of them at the appropriate condition. The influences of absorbed dose on the volume swelling ratio, molecular weight between crosslinks, gel fraction, and glass transition temperature of obtained powder were studied. Morphology, size and size distribution of rubber particles were examined by using scanning electron microscopy (SEM) and laser particle size analyzer (LPSA) technique, respectively. Results obtained by LPSA revealed that radiation has no effect on particle size of rubber latex but after drying, adherence properties of rubber particle causes increase in particle size of rubber powder, as shown in SEM photograph. Fourier transform infrared spectroscopy of rubber powders confirmed that with increasing the irradiation dose, characteristic peak corresponds to the >Cdbnd C< double bands decreased. Also Charlesby-Pinner equation was used to evaluate radiation yield.

A Mid-Infrared Search for Kardashev Civilizations

Science.gov (United States)

Sigurdsson, Steinn; Wright, J.; Griffith, R.; Povich, M. S.

2014-01-01

We are using the WISE all-sky Source Catalog to search for and put upper limits on the existence of extraterrestrial civilizations with large energy supplies. Any galaxy-spanning (Type III) civilization with an energy supply of more than about one percent of its stellar luminosity will have detectable mid-infrared excess, and nearby (extended) galaxies with civilizations with supplies more than about 80% of their stellar luminosity will be well-distinguished from nearly all natural sources in WISE color-color space. Mid-infrared spectra, far-infrared photometry, and radio emission from CO can all be used to distinguish extraterrestrial mid-infrared radiation from dust.

Application of infrared spectrophotometry to the identification of inorganic substances in dosage forms of Antacida group.

Science.gov (United States)

Umbreit, M H; Jedrasiewicz, A

2000-01-01

Powdered tablets from the Antacida group: Alusal, Milk of Magnesia, Alumag, Maalox, Magnosil, Alugastrin, Malugastrin, Rennie, and components deciding about their antiacidity like Al(OH)3, Mg(OH)2, Mg2Si3O8, NaAl(OH)2CO3, MgAl(OH)(SO4)2, CaCO3, MgCO3, were subjected to infrared spectrophotometric investigations. It was found that infrared spectra of each pharmaceutical compound are different and show a series of characteristic maxima, by which they can be identified with in the spectral range of 4000 cm-1-200 cm-1. Comparison of infrared spectra of finished products with spectra of their components it was showed that the application of infrared spectrophotometry methods enabled us to prove the presence of particular compounds used in formulations. Tablet mass and odorizing agents do not cause significant changes in spectra of the tablets studied, preparations from the Antacida group.

Container for nuclear fuel powders

International Nuclear Information System (INIS)

Etheredge, B.F.; Larson, R.I.

1982-01-01

A critically safe container is disclosed for the storage and rapid discharge of enriched nuclear fuel material in powder form is disclosed. The container has a hollow, slab-shaped container body that has one critically safe dimension. A powder inlet is provided on one side wall of the body adjacent to a corner thereof and a powder discharge port is provided at another corner of the body approximately diagonal the powder inlet. Gas plenum for moving the powder during discharge are located along the side walls of the container adjacent the discharge port

Polarized neutron powder diffraction studies of antiferromagnetic order in bulk and nanoparticle NiO

DEFF Research Database (Denmark)

Brok, Erik; Lefmann, Kim; Deen, Pascale P.

2015-01-01

surface contribution to the magnetic anisotropy. Here we explore the potential use of polarized neutron diffraction to reveal the magnetic structure in NiO bulk and nanoparticle powders by applying the XYZ-polarization analysis method. Our investigations address in particular the spin orientation in bulk....... The results show that polarization analyzed neutron powder diffraction is a viable method to investigate magnetic order in powders of antiferromagnetic nanoparticles.......In many materials it remains a challenge to reveal the nature of magnetic correlations, including antiferromagnetism and spin disorder. Revealing the spin structure in magnetic nanoparticles is further complicated by the large incoherent neutron scattering cross section from water adsorbed...

Effects of selling public intervention stocks of skimmed milk powder

NARCIS (Netherlands)

Jongeneel, Roel; Silvis, Huib; Verhoog, David; Daatselaar, Co

2018-01-01

At the request of the Dutch Ministry of Agriculture, Nature and Food Quality, this report analyses the potential market impacts and budgetary effects of different strategies of selling EU public intervention stocks of skimmed milk powder
(SMP). A gradual phasing out of the EU's SMP stocks over

Preparation of superconductor precursor powders

Science.gov (United States)

Bhattacharya, Raghunath

1998-01-01

A process for the preparation of a precursor metallic powder composition for use in the subsequent formation of a superconductor. The process comprises the steps of providing an electrodeposition bath comprising an electrolyte medium and a cathode substrate electrode, and providing to the bath one or more soluble salts of one or more respective metals which are capable of exhibiting superconductor properties upon subsequent appropriate treatment. The bath is continually energized to cause the metallic and/or reduced particles formed at the electrode to drop as a powder from the electrode into the bath, and this powder, which is a precursor powder for superconductor production, is recovered from the bath for subsequent treatment. The process permits direct inclusion of all metals in the preparation of the precursor powder, and yields an amorphous product mixed on an atomic scale to thereby impart inherent high reactivity. Superconductors which can be formed from the precursor powder include pellet and powder-in-tube products.

Standard specification for nuclear-grade zirconium oxide powder

CERN Document Server

American Society for Testing and Materials. Philadelphia

2008-01-01

1.1 This specification defines the physical and chemical requirements for zirconium oxide powder intended for fabrication into shapes, either entirely or partially of zirconia, for use in a nuclear reactor core. 1.2 The material described herein shall be particulate in nature. 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

Chemical and toxicological assessment of arsenic sorption onto Fe-sericite composite powder and beads.

Science.gov (United States)

Kim, Jiwon; Lee, Cheongho; Lee, Seung Mok; Lalhmunsiama; Jung, Jinho

2018-01-01

Batch sorption and leaching of arsenic (1-30mgL -1 ) on Fe-sericite composite powder and beads were investigated in this study. Fe-sericite composite powder was made from natural sericite modified with iron, and alginate was used to transform the powder into beads. The maximum sorption capacities of the Fe-sericite composite powder (15.04 and 13.21mgg -1 for As(III) and As(V), respectively) were higher than those of the corresponding beads (9.02 and 7.11mgg -1 for As(III) and As(V), respectively) owing to the higher specific surface area of the powder. In addition, the leaching amounts of As(III) from Fe-sericite composite beads (≤ 15.03%) were higher than those of the corresponding powder (≤ 5.71%). However, acute toxicity of As(III)-sorbed Fe-sericite composite beads toward Daphnia magna was not significantly different from that of the corresponding powder (p > 0.05). Considering higher uptake of the powder particles by the daphnids, Fe-sericite composite beads seem to be a more appropriate and safer sorbent for arsenic removal in practical application. Based on Fe content, Fe-sericite composite beads had similar or higher maximum sorption capacities (71.19 and 56.11mgg -1 Fe for As(III) and As(V), respectively) than those of previously reported sorbents. Copyright © 2017 Elsevier Inc. All rights reserved.

Cacao seeds are a "Super Fruit": A comparative analysis of various fruit powders and products.

Science.gov (United States)

Crozier, Stephen J; Preston, Amy G; Hurst, Jeffrey W; Payne, Mark J; Mann, Julie; Hainly, Larry; Miller, Debra L

2011-02-07

Numerous popular media sources have developed lists of "Super Foods" and, more recently, "Super Fruits". Such distinctions often are based on the antioxidant capacity and content of naturally occurring compounds such as polyphenols within those whole fruits or juices of the fruit which may be linked to potential health benefits. Cocoa powder and chocolate are made from an extract of the seeds of the fruit of the Theobroma cacao tree. In this study, we compared cocoa powder and cocoa products to powders and juices derived from fruits commonly considered "Super Fruits". Various fruit powders and retail fruit products were obtained and analyzed for antioxidant capacity (ORAC (μM TE/g)), total polyphenol content (TP (mg/g)), and total flavanol content (TF (mg/g)). Among the various powders that were tested, cocoa powder was the most concentrated source of ORAC and TF. Similarly, dark chocolate was a significantly more concentrated source of ORAC and TF than the fruit juices. Cocoa powder and dark chocolate had equivalent or significantly greater ORAC, TP, and TF values compared to the other fruit powders and juices tested, respectively. Cacao seeds thus provide nutritive value beyond that derived from their macronutrient composition and appear to meet the popular media's definition of a "Super Fruit".

Cacao seeds are a "Super Fruit": A comparative analysis of various fruit powders and products

Science.gov (United States)

2011-01-01

Background Numerous popular media sources have developed lists of "Super Foods" and, more recently, "Super Fruits". Such distinctions often are based on the antioxidant capacity and content of naturally occurring compounds such as polyphenols within those whole fruits or juices of the fruit which may be linked to potential health benefits. Cocoa powder and chocolate are made from an extract of the seeds of the fruit of the Theobroma cacao tree. In this study, we compared cocoa powder and cocoa products to powders and juices derived from fruits commonly considered "Super Fruits". Results Various fruit powders and retail fruit products were obtained and analyzed for antioxidant capacity (ORAC (μM TE/g)), total polyphenol content (TP (mg/g)), and total flavanol content (TF (mg/g)). Among the various powders that were tested, cocoa powder was the most concentrated source of ORAC and TF. Similarly, dark chocolate was a significantly more concentrated source of ORAC and TF than the fruit juices. Conclusions Cocoa powder and dark chocolate had equivalent or significantly greater ORAC, TP, and TF values compared to the other fruit powders and juices tested, respectively. Cacao seeds thus provide nutritive value beyond that derived from their macronutrient composition and appear to meet the popular media's definition of a "Super Fruit". PMID:21299842

Cacao seeds are a "Super Fruit": A comparative analysis of various fruit powders and products

Directory of Open Access Journals (Sweden)

Mann Julie

2011-02-01

Full Text Available Abstract Background Numerous popular media sources have developed lists of "Super Foods" and, more recently, "Super Fruits". Such distinctions often are based on the antioxidant capacity and content of naturally occurring compounds such as polyphenols within those whole fruits or juices of the fruit which may be linked to potential health benefits. Cocoa powder and chocolate are made from an extract of the seeds of the fruit of the Theobroma cacao tree. In this study, we compared cocoa powder and cocoa products to powders and juices derived from fruits commonly considered "Super Fruits". Results Various fruit powders and retail fruit products were obtained and analyzed for antioxidant capacity (ORAC (μM TE/g, total polyphenol content (TP (mg/g, and total flavanol content (TF (mg/g. Among the various powders that were tested, cocoa powder was the most concentrated source of ORAC and TF. Similarly, dark chocolate was a significantly more concentrated source of ORAC and TF than the fruit juices. Conclusions Cocoa powder and dark chocolate had equivalent or significantly greater ORAC, TP, and TF values compared to the other fruit powders and juices tested, respectively. Cacao seeds thus provide nutritive value beyond that derived from their macronutrient composition and appear to meet the popular media's definition of a "Super Fruit".

Magnetically responsive enzyme powders

Energy Technology Data Exchange (ETDEWEB)

Pospiskova, Kristyna, E-mail: kristyna.pospiskova@upol.cz [Regional Centre of Advanced Technologies and Materials, Palacky University, Slechtitelu 11, 783 71 Olomouc (Czech Republic); Safarik, Ivo, E-mail: ivosaf@yahoo.com [Regional Centre of Advanced Technologies and Materials, Palacky University, Slechtitelu 11, 783 71 Olomouc (Czech Republic); Department of Nanobiotechnology, Institute of Nanobiology and Structural Biology of GCRC, Na Sadkach 7, 370 05 Ceske Budejovice (Czech Republic)

2015-04-15

Powdered enzymes were transformed into their insoluble magnetic derivatives retaining their catalytic activity. Enzyme powders (e.g., trypsin and lipase) were suspended in various liquid media not allowing their solubilization (e.g., saturated ammonium sulfate and highly concentrated polyethylene glycol solutions, ethanol, methanol, 2-propanol) and subsequently cross-linked with glutaraldehyde. Magnetic modification was successfully performed at low temperature in a freezer (−20 °C) using magnetic iron oxides nano- and microparticles prepared by microwave-assisted synthesis from ferrous sulfate. Magnetized cross-linked enzyme powders were stable at least for two months in water suspension without leakage of fixed magnetic particles. Operational stability of magnetically responsive enzymes during eight repeated reaction cycles was generally without loss of enzyme activity. Separation of magnetically modified cross-linked powdered enzymes from reaction mixtures was significantly simplified due to their magnetic properties. - Highlights: • Cross-linked enzyme powders were prepared in various liquid media. • Insoluble enzymes were magnetized using iron oxides particles. • Magnetic iron oxides particles were prepared by microwave-assisted synthesis. • Magnetic modification was performed under low (freezing) temperature. • Cross-linked powdered trypsin and lipase can be used repeatedly for reaction.

Sintered aluminium powders

International Nuclear Information System (INIS)

Stepanova, M.G.; Matveev, B.I.

1974-01-01

The mechanical and physical properties of aluminium powder alloys and the various methods employed to produce them are considered. Data are given on the hardening of the alloys SAP and SPAK-4, as well as the powder-alloy system Al-Cr-Zr. (L.M.)

Powder diffraction

Energy Technology Data Exchange (ETDEWEB)

Hart, M.

1995-12-31

the importance of x-ray powder diffraction as an analytical tool for phase identification of materials was first pointed out by Debye and Scherrer in Germany and, quite independently, by Hull in the US. Three distinct periods of evolution lead to ubiquitous application in many fields of science and technology. In the first period, until the mid-1940`s, applications were and developed covering broad categories of materials including inorganic materials, minerals, ceramics, metals, alloys, organic materials and polymers. During this formative period, the concept of quantitative phase analysis was demonstrated. In the second period there followed the blossoming of technology and commercial instruments became widely used. The history is well summarized by Parrish and by Langford and Loueer. By 1980 there were probably 10,000 powder diffractometers in routine use, making it the most widely used of all x-ray crystallographic instruments. In the third, present, period data bases became firmly established and sophisticated pattern fitting and recognition software made many aspects of powder diffraction analysis routine. High resolution, tunable powder diffractometers were developed at sources of synchrotron radiation. The tunability of the spectrum made it possible to exploit all the subtleties of x-ray spectroscopy in diffraction experiments.

Powder diffraction

International Nuclear Information System (INIS)

Hart, M.

1995-01-01

The importance of x-ray powder diffraction as an analytical tool for phase identification of materials was first pointed out by Debye and Scherrer in Germany and, quite independently, by Hull in the US. Three distinct periods of evolution lead to ubiquitous application in many fields of science and technology. In the first period, until the mid-1940's, applications were and developed covering broad categories of materials including inorganic materials, minerals, ceramics, metals, alloys, organic materials and polymers. During this formative period, the concept of quantitative phase analysis was demonstrated. In the second period there followed the blossoming of technology and commercial instruments became widely used. The history is well summarized by Parrish and by Langford and Loueer. By 1980 there were probably 10,000 powder diffractometers in routine use, making it the most widely used of all x-ray crystallographic instruments. In the third, present, period data bases became firmly established and sophisticated pattern fitting and recognition software made many aspects of powder diffraction analysis routine. High resolution, tunable powder diffractometers were developed at sources of synchrotron radiation. The tunability of the spectrum made it possible to exploit all the subtleties of x-ray spectroscopy in diffraction experiments

Method to blend separator powders

Science.gov (United States)

Guidotti, Ronald A.; Andazola, Arthur H.; Reinhardt, Frederick W.

2007-12-04

A method for making a blended powder mixture, whereby two or more powders are mixed in a container with a liquid selected from nitrogen or short-chain alcohols, where at least one of the powders has an angle of repose greater than approximately 50 degrees. The method is useful in preparing blended powders of Li halides and MgO for use in the preparation of thermal battery separators.

Kinetic Study of Zn2+ and Cd2+ Ions Sorption by Ceric Oxide Powder

International Nuclear Information System (INIS)

Hassan, H.S.; Abd El-Rahman, K.M.; El Sayed, A.A.

2008-01-01

Ceric Oxide powder was chemically synthesized and characterized using infrared spectra and x-ray diffraction. The sorptive removal of Zinc and Cadmium ions from aqueous waste solution using synthetic ceric oxide powder was investigated using batch technique. Experiments were carried out as a function of ph, particle size, solute concentration and temperature. The uptake of zinc was found to be greater than that of cadmium. A comparison of kinetic models applied to the sorption process of each ion was evaluated for the pseudo first order, the pseudo second order, and homogeneous particle diffusion kinetic models, respectively. The results showed that both the pseudo second order and the homogeneous particle diffusion model (HPDM) were found to best correlate the experimental rate data. The numerical values of the rate constants and particle diffusion coefficients were determined from the graphical representation of the proposed models. Activation energy (Ε a ) and entropy (δ S * ) of activation for each sorption process were also calculated from the linearized form of Arrhenius equation

Magnetic, hyperthermic and structural properties of zn substituted CaFe2O4 powders

Science.gov (United States)

Kheradmand, Abbas; Vahidi, Omid; Masoudpanah, S. M.

2018-03-01

In the present study, we have synthesized single phase Ca1 - x Zn x Fe2O4 powders by hydrothermal method. The cation distribution between the tetrahedral and octahedral sites in the spinel structure and the magnetic properties as a function of the zinc substitution have been investigated by X-ray diffraction (XRD), infrared spectroscopy and vibrating sample magnetometer methods. The obtained XRD pattern indicated that the synthesized particles had single phase cubic spinel structure with no impurity. The magnetic measurements showed that the saturation magnetization increased from 83 to 98 emu/g with the addition of zinc due to the decrease of inversity. The particle size observed by electron microscopy decreased from 1.38 to 0.97 µm with the increase of zinc addition. The Ca0.7Zn0.3Fe2O4 powders exhibited appropriate heating capability for hyperthermia applications with the maximum AC heating temperature of 20 °C and specific loss power of 9.29 W/g.

The use of gamma irradiation in preparation of polybutadiene rubber nanopowder; Its effect on particle size, morphology and crosslink structure of the powder

Energy Technology Data Exchange (ETDEWEB)

Rezaei Abadchi, Majid; Jalali-Arani, Azam, E-mail: ajalali@aut.ac.ir

2014-02-01

Highlights: • Vulcanized rubber powders were prepared by spray drying of irradiated rubber latexes. • Influence of absorbed dose on powder structure and characteristics was investigated. • The size of rubber latex particles did not changed by irradiation. • Crosslink density increased by increasing dose and 98% gel was obtained at 150 kGy. • T{sub g} of rubber powder increased with increasing the irradiation dose. -- Abstract: The aim of this work was the preparation and characterization of polybutadiene rubber (BR) powder by irradiating of rubber lattices using {sup 60}Co radiation and spray-drying of them at the appropriate condition. The influences of absorbed dose on the volume swelling ratio, molecular weight between crosslinks, gel fraction, and glass transition temperature of obtained powder were studied. Morphology, size and size distribution of rubber particles were examined by using scanning electron microscopy (SEM) and laser particle size analyzer (LPSA) technique, respectively. Results obtained by LPSA revealed that radiation has no effect on particle size of rubber latex but after drying, adherence properties of rubber particle causes increase in particle size of rubber powder, as shown in SEM photograph. Fourier transform infrared spectroscopy of rubber powders confirmed that with increasing the irradiation dose, characteristic peak corresponds to the >C=C< double bands decreased. Also Charlesby–Pinner equation was used to evaluate radiation yield.

The use of gamma irradiation in preparation of polybutadiene rubber nanopowder; Its effect on particle size, morphology and crosslink structure of the powder

International Nuclear Information System (INIS)

Rezaei Abadchi, Majid; Jalali-Arani, Azam

2014-01-01

Highlights: • Vulcanized rubber powders were prepared by spray drying of irradiated rubber latexes. • Influence of absorbed dose on powder structure and characteristics was investigated. • The size of rubber latex particles did not changed by irradiation. • Crosslink density increased by increasing dose and 98% gel was obtained at 150 kGy. • T g of rubber powder increased with increasing the irradiation dose. -- Abstract: The aim of this work was the preparation and characterization of polybutadiene rubber (BR) powder by irradiating of rubber lattices using 60 Co radiation and spray-drying of them at the appropriate condition. The influences of absorbed dose on the volume swelling ratio, molecular weight between crosslinks, gel fraction, and glass transition temperature of obtained powder were studied. Morphology, size and size distribution of rubber particles were examined by using scanning electron microscopy (SEM) and laser particle size analyzer (LPSA) technique, respectively. Results obtained by LPSA revealed that radiation has no effect on particle size of rubber latex but after drying, adherence properties of rubber particle causes increase in particle size of rubber powder, as shown in SEM photograph. Fourier transform infrared spectroscopy of rubber powders confirmed that with increasing the irradiation dose, characteristic peak corresponds to the >C=C< double bands decreased. Also Charlesby–Pinner equation was used to evaluate radiation yield

Infrared synchrotron radiation from electron storage rings

International Nuclear Information System (INIS)

Duncan, W.D.; Williams, G.P.

1983-01-01

Simple and useful approximations, valid at infrared wavelengths, to the equations for synchrotron radiation are presented and used to quantify the brightness and power advantage of current synchrotron radiation light sources over conventional infrared broadband laboratory sources. The Daresbury Synchrotron Radiation Source (SRS) and the Brookhaven National Synchrotron Light Source (vacuum ultraviolet) [NSLS(VUV)] storage rings are used as examples in the calculation of the properties of infrared synchrotron radiation. The pulsed nature of the emission is also discussed, and potential areas of application for the brightness, power, and time structure advantages are presented. The use of infrared free electron lasers and undulators on the next generation of storage ring light sources is briefly considered

Methodological effects in Fourier transform infrared (FTIR) spectroscopy: Implications for structural analyses of biomacromolecular samples

Science.gov (United States)

Kamnev, Alexander A.; Tugarova, Anna V.; Dyatlova, Yulia A.; Tarantilis, Petros A.; Grigoryeva, Olga P.; Fainleib, Alexander M.; De Luca, Stefania

2018-03-01

A set of experimental data obtained by Fourier transform infrared (FTIR) spectroscopy (involving the use of samples ground and pressed with KBr, i.e. in a polar halide matrix) and by matrix-free transmission FTIR or diffuse reflectance infrared Fourier transform (DRIFT) spectroscopic methodologies (involving measurements of thin films or pure powdered samples, respectively) were compared for several different biomacromolecular substances. The samples under study included poly-3-hydroxybutyrate (PHB) isolated from cell biomass of the rhizobacterium Azospirillum brasilense; dry PHB-containing A. brasilense biomass; pectin (natural carboxylated heteropolysaccharide of plant origin; obtained from apple peel) as well as its chemically modified derivatives obtained by partial esterification of its galacturonide-chain hydroxyl moieties with palmitic, oleic and linoleic acids. Significant shifts of some FTIR vibrational bands related to polar functional groups of all the biomacromolecules under study, induced by the halide matrix used for preparing the samples for spectroscopic measurements, were shown and discussed. A polar halide matrix used for preparing samples for FTIR measurements was shown to be likely to affect band positions not only per se, by affecting band energies or via ion exchange (e.g., with carboxylate moieties), but also by inducing crystallisation of metastable amorphous biopolymers (e.g., PHB of microbial origin). The results obtained have important implications for correct structural analyses of polar, H-bonded and/or amphiphilic biomacromolecular systems using different methodologies of FTIR spectroscopy.

Blue to Yellow Photoluminescence Emission and Photocatalytic Activity of Nitrogen Doping in TiO2 Powders

Directory of Open Access Journals (Sweden)

Gabriela Byzynski

2015-01-01

Full Text Available The defects caused by doping are important for understanding the increased photocatalytic activities of TiO2:N in organic reactions and in the evaluation of OH radical production after doping. TiO2:N was therefore synthesized using a modified polymeric method and N doping was performed by calcination with urea. The resulting powders were characterized using field emission scanning electron microscopy, X-ray diffraction, diffuse reflectance spectroscopy, Raman spectroscopy, Fourier transformation infrared spectroscopy, and photoluminescence emission spectroscopy (PL. N doping did not alter the morphology of the nanoparticles, and the anatase phase predominated, with the retention of the rutile phase. The band gap values, superficial areas, and crystallite sizes of the powders decreased after doping. The PL results showed an additional energy level in the TiO2:N band gap structure as a result of TiO2 lattice defects caused by doping. At low N contents, the powders showed continuous emissions from the blue region to the yellow region and a high N content shifted the PL emissions to the red region. These results suggest that the use of these powders could increase the efficiencies of solar cells and water-splitting processes. The photocatalytic activity of the powders under UVC illumination was confirmed for different organic dye molecules. The OH radical production did not change extensively after doping, as shown by experiments with terephthalic acid, and higher photocatalytic efficiencies in Rhodamine-B degradation under UVC illumination were achieved using the doped samples.

Molybdenum plasma spray powder, process for producing said powder, and coating made therefrom

International Nuclear Information System (INIS)

Lafferty, W.D.; Cheney, R.F.; Pierce, R.H.

1979-01-01

Plasma spray powders of molybdenum particles containing 0.5 to 15 weight percent oxygen and obtained by reacting molybdenum particles with oxygen or oxides in a plasma, form plasma spray coatings exhibiting hardness comparable to flame sprayed coatings formed from molybdenum wire and plasma coatings of molybdenum powders. Such oxygen rich molybdenum powders may be used to form wear resistant coatings, such as for piston rings. (author)

Synthesis of nano-sized hydroxyapatite powders through solution combustion route under different reaction conditions

International Nuclear Information System (INIS)

Ghosh, Samir Kumar; Roy, Sujit Kumar; Kundu, Biswanath; Datta, Someswar; Basu, Debabrata

2011-01-01

Calcium hydroxyapatite, Ca 10 (PO 4 ) 6 (OH) 2 (HAp) was synthesized by combustion in the aqueous system containing calcium nitrate-diammonium hydrogen orthophosphate with urea and glycine as fuels. These ceramics are important materials for biomedical applications. Thermo-gravimetric and differential thermal analysis were employed to understand the nature of synthesis process during combustion. Effects of different process parameters namely, nature of fuel (urea and glycine), fuel to oxidizer ratio (0.6-4.0) and initial furnace temperature (300-700 o C) on the combustion behavior as well as physical properties of as-formed powders were investigated. A series of combustion reactions were carried out to optimize the reaction parameters for synthesis of nano-sized HAp powders. The combustion temperature (T f ) for the oxidant and fuels were calculated to be 896 deg. C and 1035 deg. C for the stoichiometric system of urea and glycine respectively. The stoichiometric glycine-calcium nitrate produced higher flame temperature (both calculated and measured) and powder with lower specific surface area (8.75 m 2 /g) compared to the stoichiometric urea-calcium nitrate system (10.50 m 2 /g). Fuel excess combustion in both glycine and urea produced powders with higher surface area. Nanocrystalline HAp powder could be synthesized in situ with a large span of fuel to oxidizer ratio (φ) in case of urea system (0.8 < φ < 4) and (0.6 < φ < 1.5) for the glycine system. Calcium hydroxyapatite particles having diameters ranging between 20 nm and 120 nm could be successfully synthesized through optimized process variable.

SAF line powder operations

International Nuclear Information System (INIS)

Frederickson, J.R.; Horgos, R.M.

1983-10-01

An automated nuclear fuel fabrication line is being designed for installation in the Fuels and Materials Examination Facility (FMEF) near Richland, Washington. The fabrication line will consist of seven major process systems: Receiving and Powder Preparation; Powder Conditioning; Pressing and Boat Loading; Debinding, Sintering, and Property Adjustment; Boat Transport; Pellet Inspection and Finishing; and Pin Operations. Fuel powder processing through pellet pressing will be discussed in this paper

Two layer powder pressing

International Nuclear Information System (INIS)

Schreiner, H.

1979-01-01

First, significance and advantages of sintered materials consisting of two layers are pointed out. By means of the two layer powder pressing technique metal powders are formed resulting in compacts with high accuracy of shape and mass. Attributes of basic powders, different filling methods and pressing techniques are discussed. The described technique is supposed to find further applications in the field of two layer compacts in the near future

Multi-Layered Effects of Fe on EMI Shielding of Sn-Al Hotel Architectural Powder

OpenAIRE

Hung Fei-Shuo

2016-01-01

No evident effect in shielding efficiency is observed when the electromagnetic wave-absorbing coating materials were applied in single layers because of the dispersing nature of the powder. When increased to two-layer coating, shielding effects were evident at both high and low frequencies, with greater shielding efficiency at low frequencies over high frequencies. It is worth noting that when increased to three-layer coating, as the weight percentage of powdered Fe increased from 5% to 8% , ...

Influence of Cu substitution on the structural ordering, photocatalytic activity and photoluminescence emission of Ag3-2xCuxPO4 powders

Science.gov (United States)

Pereira, Wyllamanney da S.; Sczancoski, Júlio C.; Calderon, Yormary N. C.; Mastelaro, Valmor R.; Botelho, Gleice; Machado, Thales R.; Leite, Edson R.; Longo, Elson

2018-05-01

Materials presenting high photocatalytic performance and interesting photoluminescence emissions are promising candidates for photodegradation of organic pollutants discharged into natural waters as well as for development of new electro-optical devices, respectively. In this study, Ag3-2xCuxPO4 (x = 0.00, 0.01, 0.02, 0.04 and 0.08) powders were synthesized by the precipitation method. The long- and short-range structural ordering was affected when the copper (Cu) content was increased in the lattice, as identified by X-ray diffraction patterns, Fourier transform infrared spectroscopy and Raman spectroscopy, respectively. The field emission scanning electron microscope and transmission electron microscope revealed a particle system composed of irregular spherical-like microcrystals. The presence of Cu as well as its real amount in the samples were confirmed by means of X-ray photoelectron spectroscopy and inductively coupled plasma-atomic emission spectrometry, respectively. On increasing Cu level, a slight variation was noted on the photocatalytic activity of Ag3-2xCuxPO4 powders for degradation of rhodamine B under visible light irradiation. A photodegradation mechanism was proposed in details. The photoluminescence emissions were explained by electronic transitions involving intermediary energy levels in the band gap. The origin these energy levels was related to defects caused by the substitution of Ag by Cu in the crystalline structure.

Correlation between UO2 powder and pellet quality in PHWR fuel manufacturing

International Nuclear Information System (INIS)

Glodeanu, F.; Spinzi, M.; Balan, V.

1988-01-01

Natural uranium dioxide fuel for heavy water reactors has a series of very tightly controlled quality factors: Chemical purity, density and microstructures. Although the fabrication history may consistently affect the fuel quality, the quality factor mentioned above are function mainly of the quality of the powder used as raw material. As regards the fulfilment of the requirements for very high density of the pellets, it was found that in a definite technology the raw material plays the decisive part. Except for the powder sinterability, one found other important subtile parameters, such as the degree of agglomeration and structural homogeneity. The fuel microstructure, very important for in-serive performances of the fuel, is related to a great extent to some powder characteristics (homogeneity, sinterability). This is why much stress was laid on UO 2 power quality evaluation both by standard methods and non-conventional ones (agglomeration, microscopy, X-rays). Some of the characteristics defined by product specification, such as powder sinterability, should be better defined to guarantee the final product quality. (orig.)

The analysis of powder diffraction data

International Nuclear Information System (INIS)

David, W.I.F.; Harrison, W.T.A.

1986-01-01

The paper reviews neutron powder diffraction data analysis, with emphasis on the structural aspects of powder diffraction and the future possibilities afforded by the latest generation of very high resolution neutron and x-ray powder diffractometers. Traditional x-ray powder diffraction techniques are outlined. Structural studies by powder diffraction are discussed with respect to the Rietveld method, and a case study in the Rietveld refinement method and developments of the Rietveld method are described. Finally studies using high resolution powder diffraction at the Spallation Neutron Source, ISIS at the Rutherford Appleton Laboratory are summarized. (U.K.)

Simple method of preparing nitrogen - doped nanosized TiO2 powders of high photocatalytic activity under visible light

International Nuclear Information System (INIS)

Nguyen Van Hung; Dang Thi Thanh Le

2014-01-01

Nitrogen-doped nanosized TiO 2 powders were prepared by a simple thermal treatment method of the mixture of titanium dioxide and urea. The prepared products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-Vis diffuse reflectance spectra (UV-Vis-DRS) and Fourier transform infrared (FT-IR) spectroscopy. The results showed that the crystal structure of N-TiO 2 was a mixture of anatase and rutile phases, and the average particle size was 31 nm calculated from XRD results. The UV-vis spectra indicate an increase in absorption of visible light when compared to undoped TiO 2 . The photocatalytic activity of nitrogen-doped TiO 2 powder was evaluated by the decomposition of methylene blue under visible light irradiation. And it was found that nitrogen-doped TiO 2 powders exhibited much higher photocatalytic activity than undoped TiO 2 . Moreover, the study also showed that, the doping N atoms improve the growth of the TiO 2 crystal and phase transformation. (author)

Green synthesis of silver nanoparticles using cranberry powder aqueous extract: characterization and antimicrobial properties.

Science.gov (United States)

Ashour, Asmaa A; Raafat, Dina; El-Gowelli, Hanan M; El-Kamel, Amal H

2015-01-01

The growing threat of microbial resistance against traditional antibiotics has prompted the development of several antimicrobial nanoparticles (NPs), including silver NPs (AgNPs). In this article, a simple and eco-friendly method for the synthesis of AgNPs using the cranberry powder aqueous extract is reported. Cranberry powder aqueous extracts (0.2%, 0.5%, and 0.8% w/v) were allowed to interact for 24 hours with a silver nitrate solution (10 mM) at 30°C at a ratio of 1:10. The formation of AgNPs was confirmed by ultraviolet-visible spectroscopy and their concentrations were determined using atomic absorption spectroscopy. The prepared NPs were evaluated by transmission electron microscopy, measurement of ζ-potential, and Fourier-transform infrared spectroscopy. The in vitro antimicrobial properties of AgNPs were then investigated against several microbial strains. Finally, in vivo appraisal of both wound-healing and antimicrobial properties of either plain AgNPs (prepared using 0.2% extract) or AgNP-Pluronic F-127 gel was conducted in a rat model after induction of a Staphylococcus aureus ATCC 6538P wound infection. The formation of AgNPs was confirmed by ultraviolet-visible spectroscopy, where a surface-plasmon resonance absorption peak was observed between 432 and 438 nm. Both size and concentration of the formed AgNPs increased with increasing concentration of the extracts. The developed NPs were stable, almost spherical, and polydisperse, with a size range of 1.4-8.6 nm. The negative ζ-potential values, as well as Fourier-transform infrared spectroscopy analysis, indicated the presence of a capping agent adsorbed onto the surface of the particles. In vitro antimicrobial evaluation revealed a size-dependent activity of the AgNPs against the tested organisms. Finally, AgNPs prepared using 0.2% extract exhibited a substantial in vivo healing potential for full-thickness excision wounds in rats. AgNPs were successfully synthesized from a silver nitrate solution

Roller compaction of moist pharmaceutical powders.

Science.gov (United States)

Wu, C-Y; Hung, W-L; Miguélez-Morán, A M; Gururajan, B; Seville, J P K

2010-05-31

The compression behaviour of powders during roller compaction is dominated by a number of factors, such as process conditions (roll speed, roll gap, feeding mechanisms and feeding speed) and powder properties (particle size, shape, moisture content). The moisture content affects the powder properties, such as the flowability and cohesion, but it is not clear how the moisture content will influence the powder compression behaviour during roller compaction. In this study, the effect of moisture contents on roller compaction behaviour of microcrystalline cellulose (MCC, Avicel PH102) was investigated experimentally. MCC samples of different moisture contents were prepared by mixing as-received MCC powder with different amount of water that was sprayed onto the powder bed being agitated in a rotary mixer. The flowability of these samples were evaluated in terms of the poured angle of repose and flow functions. The moist powders were then compacted using the instrumented roller compactor developed at the University of Birmingham. The flow and compression behaviour during roller compaction and the properties of produced ribbons were examined. It has been found that, as the moisture content increases, the flowability of moist MCC powders decreases and the powder becomes more cohesive. As a consequence of non-uniform flow of powder into the compaction zone induced by the friction between powder and side cheek plates, all produced ribbons have a higher density in the middle and lower densities at the edges. For the ribbons made of powders with high moisture contents, different hydration states across the ribbon width were also identified from SEM images. Moreover, it was interesting to find that these ribbons were split into two halves. This is attributed to the reduction in the mechanical strength of moist powder compacts with high moisture contents produced at high compression pressures. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Factors affecting the electrostatic charge of ceramic powders; Factores que afectan la carga electrostatica en polvos ceremicos

Energy Technology Data Exchange (ETDEWEB)

Lorite, I; Romero, J; Fernandez, J F

2011-07-01

The phenomenon of electrostatic charge in ceramic powders takes place when the particle surfaces enter in contact between them or with the containers. The accumulation of electrostatic charge is of relevance in ceramic powders in view of their insulating character and the risk of explosions during the material handling. In this work the main factors that affect the appearance of intrinsic charge and tribo-charge in ceramic powder have been studied. In ceramic powders of alumina it has been verified that the smallest particle sizes present an increase of the electrostatic charge of negative polarity. A correlation has been observed between the nature of the OH -surface groups and the electrostatic charge. The intrinsic charge and the tribocharge in ceramic powders can be diminished by compensating the surface groups that support the charge. The dry dispersion of nanoparticles on microparticles allows surface charge compensation with a noticeable modification of the powder agglomeration. (Author) 19 refs.

Black powder in gas pipelines

Energy Technology Data Exchange (ETDEWEB)

Sherik, Abdelmounam [Saudi Aramco, Dhahran (Saudi Arabia)

2009-07-01

Despite its common occurrence in the gas industry, black powder is a problem that is not well understood across the industry, in terms of its chemical and physical properties, source, formation, prevention or management of its impacts. In order to prevent or effectively manage the impacts of black powder, it is essential to have knowledge of its chemical and physical properties, formation mechanisms and sources. The present paper is divided into three parts. The first part of this paper is a synopsis of published literature. The second part reviews the recent laboratory and field work conducted at Saudi Aramco Research and Development Center to determine the compositions, properties, sources and formation mechanisms of black powder in gas transmission systems. Microhardness, nano-indentation, X-ray Diffraction (XRD), X-ray Fluorescence (XRF) and Scanning Electron Microscopy (SEM) techniques were used to analyze a large number of black powder samples collected from the field. Our findings showed that black powder is generated inside pipelines due to internal corrosion and that the composition of black powder is dependent on the composition of transported gas. The final part presents a summary and brief discussion of various black powder management methods. (author)

Mid-infrared Semiconductor Optoelectronics

CERN Document Server

Krier, Anthony

2006-01-01

The practical realisation of optoelectronic devices operating in the 2–10 µm (mid-infrared) wavelength range offers potential applications in a variety of areas from environmental gas monitoring around oil rigs and landfill sites to the detection of pharmaceuticals, particularly narcotics. In addition, an atmospheric transmission window exists between 3 µm and 5 µm that enables free-space optical communications, thermal imaging applications and the development of infrared measures for "homeland security". Consequently, the mid-infrared is very attractive for the development of sensitive optical sensor instrumentation. Unfortunately, the nature of the likely applications dictates stringent requirements in terms of laser operation, miniaturisation and cost that are difficult to meet. Many of the necessary improvements are linked to a better ability to fabricate and to understand the optoelectronic properties of suitable high-quality epitaxial materials and device structures. Substantial progress in these m...

Thermal plasma spheroidization and spray deposition of barium titanate powder and characterization of the plasma sprayable powder

Energy Technology Data Exchange (ETDEWEB)

Pakseresht, A.H., E-mail: amirh_pak@yahoo.com [Department of Ceramics, Materials and Energy Research Center, P.O. Box 31787-316, Karaj (Iran, Islamic Republic of); Rahimipour, M.R. [Department of Ceramics, Materials and Energy Research Center, P.O. Box 31787-316, Karaj (Iran, Islamic Republic of); Vaezi, M.R. [Department of Nanotechnology and Advanced Materials, Materials and Energy Research Center, P.O. Box 31787-316, Karaj (Iran, Islamic Republic of); Salehi, M. [Department of Materials Engineering, Isfahan University of Technology, P.O. Box 84156-83111, Isfahan (Iran, Islamic Republic of)

2016-04-15

In this paper, atmospheric plasma spray method was used to produce dense plasma sprayable powder and thick barium titanate film. In this regard, the commercially feedstock powders were granulated and spheroidized by the organic binder and the thermal spray process, respectively. Scanning electron microscopy was used to investigate the microstructure of the produced powders and the final deposits. X-ray diffraction was also implemented to characterize phase of the sprayed powder. The results indicated that spheroidized powder had suitable flowability as well as high density. The micro-hardness of the film produced by the sprayed powders was higher than that of the film deposited by the irregular granules. Additionally, relative permittivity of the films was increased by decreasing the defects from 160 to 293 for film deposited using spheroidized powder. The reduction in the relative permittivity of deposits, in comparison with the bulk material, was due to the existence of common defects in the thermal spray process. - Highlights: • We prepare sprayable BaTiO{sub 3} powder with no or less inside voids for plasma spray application for first time. • The sprayable powder has good flow characteristics and high density. • Powder spheroidization via plasma spray improves the hardness and dielectric properties of the deposited film.

Thermal plasma spheroidization and spray deposition of barium titanate powder and characterization of the plasma sprayable powder

International Nuclear Information System (INIS)

Pakseresht, A.H.; Rahimipour, M.R.; Vaezi, M.R.; Salehi, M.

2016-01-01

In this paper, atmospheric plasma spray method was used to produce dense plasma sprayable powder and thick barium titanate film. In this regard, the commercially feedstock powders were granulated and spheroidized by the organic binder and the thermal spray process, respectively. Scanning electron microscopy was used to investigate the microstructure of the produced powders and the final deposits. X-ray diffraction was also implemented to characterize phase of the sprayed powder. The results indicated that spheroidized powder had suitable flowability as well as high density. The micro-hardness of the film produced by the sprayed powders was higher than that of the film deposited by the irregular granules. Additionally, relative permittivity of the films was increased by decreasing the defects from 160 to 293 for film deposited using spheroidized powder. The reduction in the relative permittivity of deposits, in comparison with the bulk material, was due to the existence of common defects in the thermal spray process. - Highlights: • We prepare sprayable BaTiO_3 powder with no or less inside voids for plasma spray application for first time. • The sprayable powder has good flow characteristics and high density. • Powder spheroidization via plasma spray improves the hardness and dielectric properties of the deposited film.

Spray Drying of High Sugar Content Foods: Improving of Product Yield and Powder Properties

OpenAIRE

Mehmet Koç; Figen Kaymak-Ertekin

2016-01-01

Spray drying is the most preferred drying method to produce powdered food in the food industry and it is also widely used to convert sugar-rich liquid foods to a powder form. During and/or after spray drying process of sugar-rich products, undesirable situation was appeared such as stickiness, high moisture affinity (hygroscopicity) and low solubility due to low molecular weight monosaccharides that found naturally in the structure. The basis of these problems was formed by low glass transiti...

Black powder removal in a Mexico gas pipeline

Energy Technology Data Exchange (ETDEWEB)

Morrow, John R. [TDW Services, Inc., New Castle, DE (United States); Drysdale, Colin; Warterfield, Bob D. [T.D.Williamson, Inc., Tulsa, OK (United States)

2008-07-01

This paper focuses on the cleaning methodology and operational constrains involved with the removal of black powder in a high pressure natural gas transmission pipeline. In this case, the accumulation of black powder along the pipeline system over the seven year period since it was put into service was creating significant problems in the areas of maintenance, customer relations, and cost to the pipeline operator due to clogging of filters, reduced gas flow, and penalties as result of non-compliant delivery contracts. The pipeline cleaning project consisted of running cleaning pigs or scrappers with batches of cleaning solution through each section of the pipeline while dealing with such factors as three (3) pipeline section lengths in excess of 160 kms (100 miles), gas flow velocity fluctuations, shutdowns, and gas delivery schedule requirements. The cleaning program for the entire pipeline system included the use of chemical and diesel based cleaning solution, running multiple cleaning pigs, liquid injection and separation system, mobile storage tanks, various equipment and personnel for logistical support. Upon completion of the cleaning program, the level of black powder and other solids in all pipeline sections was reduced to approximately 0.5% liquid/solid ratio and the pipeline system returned to normal optimum operation. (author.

Kinetic study of Cs+ and Eu3+ ions sorption by zirconium oxide powder

International Nuclear Information System (INIS)

Hanafi, H.A.; Hassan, H.S.; Hamed, M.M.

2009-01-01

Full text: Zirconium oxide powder was chemically synthesized by sol-gel method and characterized using infrared spectra and x-ray diffraction. The sorptive removal of cesium and europium ions from aqueous waste solution using synthetic zirconium oxide powder was investigated using batch technique. Experiments were carried out as a function of pH, time and temperature. The uptake of europium was found to be greater than that of cesium. A comparison of kinetic models applied to the sorption process of each ion was evaluated for the pseudo first order, the pseudo second order, and homogeneous particle diffusion kinetic models, respectively. The results showed that both the pseudo second order and the homogeneous particle diffusion models (HPDM) were found to best correlate the experimental rate data. The numerical values of the rate constants and particle diffusion coefficients were determined from the graphical representation of the proposed models. Activation energy (Ea) and entropy (Δ S*) of activation for each sorption process were also calculated from the linearized form of Arrhenius equation. (author)

Sugarcane bagasse powder as biosorbent for reactive red 120 removals from aqueous solution

Science.gov (United States)

Ahmad, S.; Wong, Y. C.; Veloo, K. V.

2018-04-01

Reactive red 120 is used as a textile dye for fabric coloring. The dye waste is produced during textile finishing process subsequently released directly to water bodies which giving harmful effects to the environment due to the carcinogenic characteristic. Adsorption process becomes an effective treatment to treat textile dye. This research emphasizes the treatment of textile dye namely reactive red 120 (RR120) by using sugarcane bagasse powder. The batch study was carried out under varying parameters such as 60 minutes contact time, pH (1-8), dye concentration (5-25 mg/L), particle size (125-500 μm) and biosorbent dosage (0.01-0.2 g/L). The maximum adsorption percentage of RR120 was 94.62%. The adsorption of dye was increased with the decreasing of pH, initial dye concentration and particle size. Sugarcane bagasse powder as low-cost biosorbent was established using Fourier Transform Infrared (FTIR) and scanning electron microscopy (SEM). This locally agricultural waste could be upgraded into useful material which is biosorbent that promising for decolorization of colored textile wastewater.

Identification of Uranium Minerals in Natural U-Bearing Rocks Using Infrared Reflectance Spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Beiswenger, Toya N. [Pacific Northwest National Laboratory, Richland, WA, USA; Gallagher, Neal B. [Eigenvector Research, Inc., Manson, WA, USA; Myers, Tanya L. [Pacific Northwest National Laboratory, Richland, WA, USA; Szecsody, James E. [Pacific Northwest National Laboratory, Richland, WA, USA; Tonkyn, Russell G. [Pacific Northwest National Laboratory, Richland, WA, USA; Su, Yin-Fong [Pacific Northwest National Laboratory, Richland, WA, USA; Sweet, Lucas E. [Pacific Northwest National Laboratory, Richland, WA, USA; Lewallen, Tricia A. [Pacific Northwest National Laboratory, Richland, WA, USA; Johnson, Timothy J. [Pacific Northwest National Laboratory, Richland, WA, USA

2017-10-24

The identification of minerals, including uranium-bearing minerals, is traditionally a labor-intensive-process using x-ray diffraction (XRD), fluorescence, or other solid-phase and wet chemical techniques. While handheld XRD and fluorescence instruments can aid in field identification, handheld infrared reflectance spectrometers can also be used in industrial or field environments, with rapid, non-destructive identification possible via spectral analysis of the solid’s reflectance spectrum. We have recently developed standard laboratory measurement methods for the infrared (IR) reflectance of solids and have investigated using these techniques for the identification of uranium-bearing minerals, using XRD methods for ground-truth. Due to the rich colors of such species, including distinctive spectroscopic signatures in the infrared, identification is facile and specific, both for samples that are pure or are partially composed of uranium (e.g. boltwoodite, schoepite, tyuyamunite, carnotite, etc.) or non-uranium minerals. The method can be used to detect not only pure and partial minerals, but is quite sensitive to chemical change such as hydration (e.g. schoepite). We have further applied statistical methods, in particular classical least squares (CLS) and multivariate curve resolution (MCR) for discrimination of such uranium minerals and two uranium pure chemicals (U3O8 and UO2) against common background materials (e.g. silica sand, asphalt, calcite, K-feldspar) with good success. Each mineral contains unique infrared spectral features; some of the IR features are similar or common to entire classes of minerals, typically arising from similar chemical moieties or functional groups in the minerals: phosphates, sulfates, carbonates, etc. These characteristic 2 infrared bands generate the unique (or class-specific) bands that distinguish the mineral from the interferents or backgrounds. We have observed several cases where the chemical moieties that provide the

Weighing fluidized powder

International Nuclear Information System (INIS)

Adomitis, J.T.; Larson, R.I.

1980-01-01

Fluidized powder is discharged from a fluidizing vessel into a container. Accurate metering is achieved by opening and closing the valve to discharge the powder in a series of short-duration periods until a predetermined weight is measured by a load cell. The duration of the discharge period may be increased in inverse proportion to the amount of powder in the vessel. Preferably the container is weighed between the discharge periods to prevent fluctuations resulting from dynamic effects. The gas discharged into the container causes the pressures in the vessel and container to equalize thereby decreasing the rate of discharge and increasing the accuracy of metering as the weight reaches the predetermined value. (author)

21 CFR 73.1647 - Copper powder.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Copper powder. 73.1647 Section 73.1647 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1647 Copper powder. (a) Identity. (1) The color additive copper powder is a very fine free-flowing metallic powder prepared from virgin electrolytic copper. It...

[Use of powder metallurgy for development of implants of Co-Cr-Mo alloy powder].

Science.gov (United States)

Dabrowski, J R

2001-04-01

This paper discusses the application of powder metallurgy for the development of porous implantation materials. Powders obtained from Co-Cr-Mo alloy with different carbon content by water spraying and grinding, have been investigated. Cold pressing and rotary re-pressing methods were used for compressing the powder. It was found that the sintered materials obtained from water spraying have the most advantageous properties.

Reducing metal alloy powder costs for use in powder bed fusion additive manufacturing: Improving the economics for production

Science.gov (United States)

Medina, Fransisco

Titanium and its associated alloys have been used in industry for over 50 years and have become more popular in the recent decades. Titanium has been most successful in areas where the high strength to weight ratio provides an advantage over aluminum and steels. Other advantages of titanium include biocompatibility and corrosion resistance. Electron Beam Melting (EBM) is an additive manufacturing (AM) technology that has been successfully applied in the manufacturing of titanium components for the aerospace and medical industry with equivalent or better mechanical properties as parts fabricated via more traditional casting and machining methods. As the demand for titanium powder continues to increase, the price also increases. Titanium spheroidized powder from different vendors has a price range from 260/kg-450/kg, other spheroidized alloys such as Niobium can cost as high as $1,200/kg. Alternative titanium powders produced from methods such as the Titanium Hydride-Dehydride (HDH) process and the Armstrong Commercially Pure Titanium (CPTi) process can be fabricated at a fraction of the cost of powders fabricated via gas atomization. The alternative powders can be spheroidized and blended. Current sectors in additive manufacturing such as the medical industry are concerned that there will not be enough spherical powder for production and are seeking other powder options. It is believed the EBM technology can use a blend of spherical and angular powder to build fully dense parts with equal mechanical properties to those produced using traditional powders. Some of the challenges with angular and irregular powders are overcoming the poor flow characteristics and the attainment of the same or better packing densities as spherical powders. The goal of this research is to demonstrate the feasibility of utilizing alternative and lower cost powders in the EBM process. As a result, reducing the cost of the raw material to reduce the overall cost of the product produced with

Synthesis of carbon nitride powder by selective etching of TiC0.3N0.7 in chlorine-containing atmosphere at moderate temperature

International Nuclear Information System (INIS)

Sui Jian; Lu Jinjun

2010-01-01

We reported the synthesis of carbon nitride powder by extracting titanium from single inorganic precursor TiC 0.3 N 0.7 in chlorine-containing atmosphere at ambient pressure and temperature not exceeding 500 deg. C. The TiC 0.3 N 0.7 crystalline structure acted as a template, supplying active carbon and nitrogen atoms for carbon nitride when it was destroyed in chlorination. X-ray diffraction data showed that the obtained carbon nitride powders were amorphous, which was in good agreement with transmission electron microscope analysis. The composition and structure of carbon nitride powders were analyzed by employing Fourier transform infrared spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. Results indicated that disorder structure was most likely for the carbon nitride powders and the N content depended greatly on the chlorination temperature. Thermal analysis in flowing N 2 indicated that the mass loss started from 300 deg. C and the complete decomposition occurred at around 650 deg. C, confirming the low thermal stability of the carbon nitride material.

MECHANICAL PROPERTIES AND WATER ABSORPTION OF KENAF POWDER FILLED RECYCLED HIGH DENSITY POLYETHYLENE/NATURAL RUBBER BIOCOMPOSITES USING MAPE AS A COMPATIBILIZER

Directory of Open Access Journals (Sweden)

Azura A. Rashid

2011-06-01

Full Text Available The performance of kenaf powder (KP filled recycled high density polyethylene (rHDPE /natural rubber (NR blends with and without a compatibilizer, maleic anhydride grafted polyethylene (MAPE, were investigated. The composites with different filler loading (0 to 40 phr were prepared with a Haake internal mixer. Increasing the KP loading in rHDPE/NR/KP biocomposites reduced the tensile strength and the elongation at break but increased the stabilization torque and the tensile modulus. The addition of MAPE as a compatibilizer increased the tensile strength, elongation at break, and modulus of the composites. This might be attributed to the enhanced adhesion between the filler and polymer matrix, as evidenced from the morphology, using scanning electron microscopy. The incorporation of compatibilizer also reduced the water absorption of the composites.

Adsorption of clofibric acid and ketoprofen onto powdered activated carbon: effect of natural organic matter.

Science.gov (United States)

Gao, Yaohuan; Deshusses, Marc A

2011-12-01

The adsorption of two acidic pharmaceutically active compounds (PhACs), clofibric acid and ketoprofen, onto powdered activated carbon (PAC) was investigated with a particular focus on the influence of natural organic matter (NOM) on the adsorption of the PhACs. Suwannee River humic acids (SRHAs) were used as a substitute for NOM. Batch adsorption experiments were conducted to obtain adsorption kinetics and adsorption isotherms with and without SRHAs in the system. The adsorption isotherms and adsorption kinetics showed that the adsorption ofclofibric acid was not significantly affected by the presence of SRHAs at a concentration of 5 mg (as carbon) L(-1). An adsorption capacity of 70 to 140 mg g(-1) was observed and equilibrium was reached within 48 h. In contrast, the adsorption of ketoprofen was markedly decreased (from about 120 mg g(-1) to 70-100 mg g(-1)) in the presence of SRHAs. Higher initial concentrations of clofibric acid than ketoprofen during testing may explain the different behaviours that were observed. Also, the more hydrophobic ketoprofen molecules may have less affinity for PAC when humic acids (which are hydrophilic) are present. The possible intermolecular forces that could account for the different behaviour of clofibric acid and ketoprofen adsorption onto PAC are discussed. In particular, the relevance of electrostatic forces, electron donor-acceptor interaction, hydrogen bonding and London dispersion forces are discussed

Magnetism and infrared magnetotransmission of Nd{sub 0.5}Sr{sub 0.5}MnO{sub 3} manganite in nanostate

Energy Technology Data Exchange (ETDEWEB)

Loshkareva, N.N., E-mail: loshkareva@imp.uran.ru; Mostovshchikova, E.V.; Korolyov, A.V.; Naumov, S.V.; Gizhevskii, B.A.; Solin, N.I.; Naumova, L.I.; Telegin, S.V.; Elokhina, L.V.

2013-09-15

The magnetic properties of nanopowders of Nd{sub 0.5}Sr{sub 0.5}MnO{sub 3} manganite, obtained by ball milling method, and IR magnetotransmission (the relative change in transmission of infrared radiation in a magnetic field) of composites based on the nanopowders are studied and compared with properties of Nd{sub 0.5}Sr{sub 0.5}MnO{sub 3} single crystal and coarse grain powder. The strong decrease of the magnetization at transformation of the single crystal to coarse grain powder is associated with the martensitic nature of the charge-ordered state (CO), T{sub CO}∼150 K. With a further decrease of particles size the magnetization decreases sharply above 150 K and is less significant in the region below 150 K, where a plateau in temperature dependence of magnetization and magnetotransmission takes place. The plateau is explained by modification of the manganite properties at milling and associated with competition of the ferromagnetic and antiferromagnetic contributions in cores and surface of the nanoparticles and change in the degree of localization of charge carriers in the magnetic field. The high value of the magnetotransmission (up to 9%) in a wide temperature range for nanocomposites are promising for creation of magnetically controlled infrared optoelectronic devices. - Highlights: • Nd{sub 0.5}Sr{sub 0.5}MnO{sub 3} nanopowders were obtained by the ball-milling method. • Difference in the magnetic properties of nanopowders and bulk crystals was revealed. • High value of IR magnetotransmition of Nd{sub 0.5}Sr{sub 0.5}MnO{sub 3} nanocomposites was found. • Relationship between magnetism and magnetotransmition of nano-Nd{sub 0.5}Sr{sub 0.5}MnO{sub 3} is shown.

Rapid analysis of adulterations in Chinese lotus root powder (LRP) by near-infrared (NIR) spectroscopy coupled with chemometric class modeling techniques.

Science.gov (United States)

Xu, Lu; Shi, Peng-Tao; Ye, Zi-Hong; Yan, Si-Min; Yu, Xiao-Ping

2013-12-01

This paper develops a rapid analysis method for adulteration identification of a popular traditional Chinese food, lotus root powder (LRP), by near-infrared spectroscopy and chemometrics. 85 pure LRP samples were collected from 7 main lotus producing areas of China to include most if not all of the significant variations likely to be encountered in unknown authentic materials. To evaluate the model specificity, 80 adulterated LRP samples prepared by blending pure LRP with different levels of four cheaper and commonly used starches were measured and predicted. For multivariate quality models, two class modeling methods, the traditional soft independent modeling of class analogy (SIMCA) and a recently proposed partial least squares class model (PLSCM) were used. Different data preprocessing techniques, including smoothing, taking derivative and standard normal variate (SNV) transformation were used to improve the classification performance. The results indicate that smoothing, taking second-order derivatives and SNV can improve the class models by enhancing signal-to-noise ratio, reducing baseline and background shifts. The most accurate and stable models were obtained with SNV spectra for both SIMCA (sensitivity 0.909 and specificity 0.938) and PLSCM (sensitivity 0.909 and specificity 0.925). Moreover, both SIMCA and PLSCM could detect LRP samples mixed with 5% (w/w) or more other cheaper starches, including cassava, sweet potato, potato and maize starches. Although it is difficult to perform an exhaustive collection of all pure LRP samples and possible adulterations, NIR spectrometry combined with class modeling techniques provides a reliable and effective method to detect most of the current LRP adulterations in Chinese market. Copyright © 2013 Elsevier Ltd. All rights reserved.

Development of "all natural" layer-by-layer redispersible solid lipid nanoparticles by nano spray drying technology.

Science.gov (United States)

Wang, Taoran; Hu, Qiaobin; Zhou, Mingyong; Xia, Yan; Nieh, Mu-Ping; Luo, Yangchao

2016-10-01

Solid lipid nanoparticles (SLNs) have gained tremendous attraction as carriers for controlled drug delivery. Despite numerous advances in the field, one long-standing historical challenge for their practical applications remains unmet: redispersibility after drying. In this work, a novel design of SLNs using a layer-by-layer (LbL) technique was developed and the formulations were optimized by surface response methodology (Box-Behnken design). To the best of our knowledge, this is the first study reporting the fabrication of SLNs from all natural ingredients in the absence of any synthetic surfactants or coatings. The SLNs were prepared by a combined solvent-diffusion and hot homogenization method, with soy lecithin as natural emulsifier (first layer), followed by the subsequent coating with sodium caseinate (second layer) and pectin (third layer), both of which are natural food biopolymers. The adsorption of pectin coating onto caseinate was reinforced by hydrophobic and electrostatic interactions induced by a pH-driven process along with thermal treatment. The innovative nano spray drying technology was further explored to obtain ultra-fine powders of SLNs. Compared to uncoated or single-layer coated SLNs powders, which showed severe aggregation after spray drying, the well-separated particles with spherical shape and smooth surface were obtained for layer-by-layer (LbL) SLNs, which were redispersible into water without variation of dimension, shape and morphology. The SLNs were characterized by Fourier transform infrared and high-performance differential scanning calorimetry for their physical properties. The LbL-coated SLNs based on all natural ingredients have promising features for future applications as drug delivery systems, overcoming the major obstacles in conventional spray drying and redispersing SLNs-based formulations. Copyright © 2016 Elsevier B.V. All rights reserved.

Crushing method for nuclear fuel powder

International Nuclear Information System (INIS)

Hasegawa, Shin-ichi; Tsuchiya, Haruo.

1997-01-01

A crushing medium is contained in mill pots disposed at the circumferential periphery of a main axis. The diameter of each mill pot is determined such that powdery nuclear fuels containing aggregated powders and ground and mixed powders do not reach criticality. A plurality of mill pots are revolved in the direction of the main axis while each pots rotating on its axis. Powdery nuclear fuels containing aggregated powders are conveyed to a supply portion of the moll pot, and an inert gas is supplied to the supply portion. The powdery nuclear fuels are supplied from the supply portion to the inside of the mill pots, and the powdery nuclear fuels containing aggregated powders are crushed by centrifugal force caused by the rotation and the revolving of the mill pots by means of the crushing medium. UO 2 powder in uranium oxide fuels can be crushed continuously. PuO 2 powder and UO 2 powder in MOX fuels can be crushed and mixed continuously. (I.N.)

Ultrafine hydrogen storage powders

Science.gov (United States)

Anderson, Iver E.; Ellis, Timothy W.; Pecharsky, Vitalij K.; Ting, Jason; Terpstra, Robert; Bowman, Robert C.; Witham, Charles K.; Fultz, Brent T.; Bugga, Ratnakumar V.

2000-06-13

A method of making hydrogen storage powder resistant to fracture in service involves forming a melt having the appropriate composition for the hydrogen storage material, such, for example, LaNi.sub.5 and other AB.sub.5 type materials and AB.sub.5+x materials, where x is from about -2.5 to about +2.5, including x=0, and the melt is gas atomized under conditions of melt temperature and atomizing gas pressure to form generally spherical powder particles. The hydrogen storage powder exhibits improved chemcial homogeneity as a result of rapid solidfication from the melt and small particle size that is more resistant to microcracking during hydrogen absorption/desorption cycling. A hydrogen storage component, such as an electrode for a battery or electrochemical fuel cell, made from the gas atomized hydrogen storage material is resistant to hydrogen degradation upon hydrogen absorption/desorption that occurs for example, during charging/discharging of a battery. Such hydrogen storage components can be made by consolidating and optionally sintering the gas atomized hydrogen storage powder or alternately by shaping the gas atomized powder and a suitable binder to a desired configuration in a mold or die.

Size Effect on the Infrared Spectra of Condensed Media under Conditions of 1D, 2D, and 3D Dielectric Confinement

KAUST Repository

Shaganov, Igor I.

2010-10-07

The effect of dielectric confinement on the peak position of intramolecular and a lattice vibration in the infrared spectra of various condensed media is investigated. Liquid benzene, carbon disulfide, and chloroform, as well as amorphous SiO2 and microcrystalline MgO particles, were characterized in this study. The absorption spectra of organic liquids and aqueous solutions of a silica submicrometer powder were measured under a variety of dielectric confinement configurations using Fourier transform Infrared spectroscopy. A significant shift of the resonant absorption band of liquid mesoparticles has been observed under dielectric confinement, which is in good agreement with model predictions. A corresponding expression for the dielectric loss spectrum of an absorbing composite medium was obtained using a Maxwell-Garnett generalized equation for the cases of one, two, and three-dimensional dielectric confinement in both ordered and disordered thin layers (disks), rods (wires or needles), and spheres of an absorbing medium. The experimental data on peak positions obtained from the infrared spectra of the organic liquids investigated in this work, as well as from the infrared spectra of amorphous quartz spherical particles and rods, are in good agreement with the calculated data. It is shown using simulations of the absorption spectrum of MgO powder that the approach suggested can be applied under certain conditions to the modeling of the spectra of microcrystalline particles of nonspheroidal shape. © 2010 American Chemical Society.

Electrochemical behaviors of wax-coated Li powder/Li 4Ti 5O 12 cells

Science.gov (United States)

Park, Han Eol; Seong, Il Won; Yoon, Woo Young

The wax-coated Li powder specimen was effectively synthesized using the drop emulsion technique (DET). The wax layer on the powder was verified by SEM, Focused Ion Beam (FIB), EDX and XPS. The porosity of a sintered wax-coated Li electrode was measured by linear sweep voltammetry (LSV) and compared with that of a bare, i.e., un-coated Li electrode. The electrochemical behavior of the wax-coated Li powder anode cell was examined by the impedance analysis and cyclic testing methods. The cyclic behavior of the wax-coated Li powder anode with the Li 4Ti 5O 12 (LTO) cathode cell was examined at a constant current density of 0.35 mA cm -2 with the cut-off voltages of 1.2-2.0 V at 25 °C. Over 90% of the initial capacity of the cell remained even after the 300th cycle. The wax-coated Li powder was confirmed to be a stable anode material.

Preparation and characterization of lactate-intercalated Co–Fe layered double hydroxides and exfoliated nanosheet film with low infrared emissivity

International Nuclear Information System (INIS)

Zhu Yunxia; Zhou Yuming; Zhang Tao; He Man; Wang Yongjuan; Yang Xiaoming; Yang Yong

2012-01-01

Highlights: ► We use ferrous, cobalt powders and lactic acid to synthesis lactate-intercalated Co–Fe layered double hydroxides successfully. ► A possible orientation of the intercalated lactate between the layers is carried out. ► The thin nanosheet film is fabricated and the surface is very smooth and flat. ► The infrared emissivity value of Co–Fe LDHs is lower than that of Zn–Al or Mg–Al LDHs, and the value is further reduced after forming a thin film. - Abstract: Lactate-intercalated Co–Fe layered double hydroxides (LDHs) were successfully prepared by coprecipitation and hydrothermal method. In this process, divalent metal ions as precursors can be obtained from the reduction reaction of lactic acid and metal powder (cobalt and ferrous). In order to obtain Fe 3+ , H 2 O 2 (30%) was used to oxidize Fe 2+ . Meanwhile, the produced lactate was intercalated into the LDHs interlayers to compensate the positively charged layers. The as-synthesized LDHs were studied by element chemical analysis, powder X-ray diffraction (XRD), FT-IR spectroscopy, thermogravitry (TG) and differential scanning calorimetry (DSC), TEM. The results indicated that the basal spacing value of the LDHs was larger than that of lactate-intercalated Mg–Al or Zn–Al LDHs. It proved that the lactate anions were inserted into the gallery in the form of dimers which made it easy to be delaminated in water. The obtained nanosheets were deposited on the substrates to form the film which was characterized by TEM and AFM, and infrared emissivity value (8–14 μm) was also investigated. The infrared emissivity values of Co–Fe LDHs were lower than that of Zn–Al which took advantage of the special electronic structure in Co and Fe. Besides, the orderly structure and the reduction of the interfacial deficiency of the film made the values further reduced.

Study of Velocity and Materials on Tribocharging of Polymer Powders for Powder Coating Applications

Science.gov (United States)

Biris, Alex S.; Trigwell, Steve; Sims, Robert A.; Mazumder, Malay K.

2005-01-01

Electrostatic powder deposition is widely used in a plethora of industrial-applications ranging from the pharmaceutical and food.industries, to farm equipment and automotive applications. The disadvantages of this technique are possible back corona (pin-like formations) onset and the Faraday penetration limitation (when the powder does not penetrate in some recessed areas). A possible solution to overcome these problems is to use tribochargers to electrostatically charge the powder. Tribocharging, or contact charging while two materials are in contact, is related to the work function difference between the contacting materials and generates bipolarly charged particles. The generation of an ion-free powder cloud by tribocharging with high bipolar charge and an overall charge density of almost zero, provides a better coverage of the recessed areas. In this study, acrylic and epoxy powders were fluidized and charged by passing through stainless steel, copper, aluminum, and polycarbonate static mixers, respectively. The particle velocity was varied to determine its effect on the net charge-to-mass ratio (QIM) acquired by the powders. In general, the Q/M increases rapidly when the velocity was increased from 1.5 to 2.5 m/s, remaining almost constant for higher velocities. Charge separation experiments showed bipolar charging for all chargers.

Dry ripened mortar with quarry waste and rubber powder from unserviceable tires

Directory of Open Access Journals (Sweden)

José Aparecido Canova

2015-01-01

Full Text Available Stone-quarry fines have been evaluated in mortar and concrete, but have presented drying shrinkage and consequently higher incidence of cracks than those with natural sand. This study compared the dry ripened mortar in two types of aggregates added of 8% rubber powder. It was used quicklime, artificial and natural sand in volumetric proportions of 1:6. Mixtures were oven-dried, received the cement, establishing the volumetric proportion of 1: 1.5:9. Inplastic state, we evaluated aspects such as consistence, air content, water retention and bleeding; whereas compressive strength, static deformation modulus and water absorption by capillarity was determined in hardened state. Cracking aspects were evaluated in substrate. As a result, the mortar with artificial sand showed higher increases in compressive strength, capillarity rate and cracking, and greater reductions in air content and bleeding. As for the rubber powder, exhibited a greater reduction in the cracking rate and capillarity was found.

Design and development of dry powder sulfobutylether-β-cyclodextrin complex for pulmonary delivery of fisetin.

Science.gov (United States)

Mohtar, Noratiqah; Taylor, Kevin M G; Sheikh, Khalid; Somavarapu, Satyanarayana

2017-04-01

This study has investigated complexation of fisetin, a natural flavonoid, with three types of cyclodextrins to improve its solubility. Sulfobutylether-β-cyclodextrin (SBE-β-CD) showed the highest complexation efficiency while maintaining the in vitro antioxidant activity of fisetin. Addition of 20%v/v ethanol in water improved the amount of solubilized fisetin in the complex 5.9-fold compared to the system containing water alone. Spray drying of fisetin-SBE-β-CD complex solution in the presence of ethanol produced a dry powder with improved aerosolization properties when delivered from a dry powder inhaler, indicated by a 2-fold increase in the fine particle fraction (FPF) compared to the powder produced from the complex solution containing water alone. The pitted morphological surface of these particles suggested a more hollow internal structure, indicating a lighter and less dense powder. Incorporation of 20%w/w leucine improved the particle size distribution of the powder and further increased the FPF by 2.3-fold. This formulation also showed an EC 50 value equivalent to fisetin alone in the A549 cell line. In conclusion, an inhalable dry powder containing fisetin-SBE-β-CD complex was successfully engineered with an improved aqueous solubility of fisetin. The dry powder may be useful to deliver high amounts of fisetin to the deep lung region for therapeutic purposes. Copyright © 2016. Published by Elsevier B.V.

A comparative approach to synthesis and sintering of alumina/yttria nanocomposite powders using different precipitants

Energy Technology Data Exchange (ETDEWEB)

Kafili, G. [Department of Nanotechnology Engineering, Faculty of Advanced Sciences and Technologies, University of Isfahan, Isfahan, 81746-73441 (Iran, Islamic Republic of); Movahedi, B., E-mail: b.movahedi@ast.ui.ac.ir [Department of Nanotechnology Engineering, Faculty of Advanced Sciences and Technologies, University of Isfahan, Isfahan, 81746-73441 (Iran, Islamic Republic of); Milani, M. [Faculty of Advanced Materials and Renewable Energy Research Center, Tehran (Iran, Islamic Republic of)

2016-11-01

Alumina/yttria nanocomposite powder as an yttrium aluminum garnet (YAG) precursor was synthesized via partial wet route using urea and ammonium hydrogen carbonate (AHC) as precipitants, respectively. The products were characterized using X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and energy dispersive spectroscopy. The use of urea produced very tiny spherical Y-compounds with chemical composition of Y{sub 2}(CO{sub 3}){sub 3}·nH{sub 2}O, which were attracted to the surface of alumina nanoparticles and consequently, a core-shell structure was obtained. The use of ammonium hydrogen carbonate produced sheets of Y-compounds with chemical composition of Y(OH)CO{sub 3} covering the alumina nanoparticles. A fine-grained YAG ceramic (about 500 nm), presenting a non-negligible transparency (45% RIT at IR range) was obtained by the spark plasma sintering (SPS) of alumina-yttria nanocomposite synthesized in the urea system. This amount of transmission was obtained by only the sintering of the powder specimen without any colloidal forming process before sintering or adding any sintering aids or dopant elements. However, by spark plasma sintering of alumina-yttria nanocomposite powder synthesized in AHC system, an opaque YAG ceramic with an average grain size of 1.2 μm was obtained. - Highlights: • Urea proved to be an appropriate precipitant for obtaining a core-shell alumina/yttria nanocomposite. • Alumina/yttria nanocomposite powders with more appropriate morphology and highly sinterability. • A fine-grained YAG ceramic was obtained by SPS of alumina-yttria nanocomposite.

Natural zeolite reactivity towards ozone: The role of compensating cations

International Nuclear Information System (INIS)

Valdés, Héctor; Alejandro, Serguei; Zaror, Claudio A.

2012-01-01

Highlights: ► Chemical and thermal treatment enhances catalytic activity of natural zeolite. ► Modified natural zeolite exhibits high stability after thermal treatment. ► Reducing the compensating cation content leads to an increase on ozone abatement. ► Surface active atomic oxygen was detected using the DRIFT technique. ► The highest reactivity toward ozone was performed by NH4Z3 zeolite sample. - Abstract: Among indoor pollutants, ozone is recognised to pose a threat to human health. Recently, low cost natural zeolites have been applied as alternative materials for ozone abatement. In this work, the effect of compensating cation content of natural zeolite on ozone removal is studied. A Chilean natural zeolite is used here as starting material. The amount of compensating cations in the zeolite framework was modified by ion exchange using an ammonium sulphate solution (0.1 mol L −1 ). Characterisation of natural and modified zeolites were performed by X-ray powder diffraction (XRD), nitrogen adsorption at 77 K, elemental analysis, X-ray fluorescence (XRF), thermogravimetric analysis coupled with mass spectroscopy (TGA-MS), and temperature-programmed desorption of ammonia (NH 3 -TPD). Ozone adsorption and/or decomposition on natural and modified zeolites were studied by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Results show that the zeolite compensating cation content affects ozone interaction with zeolite active sites. Ammonium ion-exchange treatments followed by thermal out-gassing at 823 K, reduces ozone diffusion resistance inside the zeolite framework, increasing ozone abatement on zeolite surface active sites. Weak and strong Lewis acid sites of zeolite surface are identified here as the main active sites responsible of ozone removal.

Development of a microparticle-based dry powder inhalation formulation of ciprofloxacin hydrochloride applying the quality by design approach

Directory of Open Access Journals (Sweden)

Karimi K

2016-10-01

Full Text Available Keyhaneh Karimi, Edina Pallagi, Piroska Szabó-Révész, Ildikó Csóka, Rita Ambrus Faculty of Pharmacy, Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Szeged, Hungary Abstract: Pulmonary drug delivery of ciprofloxacin hydrochloride offers effective local antibacterial activity and convenience of easy application. Spray drying is a trustworthy technique for the production of ciprofloxacin hydrochloride microparticles. Quality by design (QbD, an up-to-date regulatory-based quality management method, was used to predict the final quality of the product. According to the QbD-based theoretical preliminary parameter ranking and priority classification, dry powder inhalation formulation tests were successfully performed in practice. When focusing on the critical parameters, the practical development was more effective and was in correlation with our previous findings. Spray drying produced spherical microparticles. The dry powder formulations prepared were examined by particle size analysis, scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray powder diffraction, differential scanning calorimetry, and in vitro drug release and aerodynamic particle size analyses were also performed. These formulations showed an appropriate particle size ranging between 2 and 4 µm and displayed an enhanced aerosol performance with fine particle fraction up to 80%. Keywords: antibiotic, carrier-free formulation, quality by design, aerodynamic evaluation, dry powder for inhalation

Sorption activity investigation of ultrafine powders of high temperature melting point compounds in atmospheric pressure conditions

International Nuclear Information System (INIS)

Rudneva, V.V.

2006-01-01

A study is made in saturation with gas in the air for ultradispersed chromium carbonitride and boride powders synthesized in a nitrogen plasma jet according to three variants: from elements, from oxides, from chromium trichloride. It is established that in the air on temperature increasing the powders adsorb considerable amounts of oxygen and water vapor. This results in surface oxidation of powder particles and a loss in specific combination of properties. Preliminary vacuum heat treatment is shown to decrease sharply the rate of atmospheric gas adsorption. The quantity of adsorbed gases is dependent on a carbon monoxide concentration in a particle surface layer and the availability of adsorption centers. The number of such centers in the layer can be controlled by vacuum heat treatment conditions. The interaction of the powders with atmospheric gases is concluded to be of adsorption-diffusion nature [ru

Far-infrared Fourier Transform Spectroscopy Measurements of Mn12-acetate.

Science.gov (United States)

Tu, Jiufeng; Suzuki, Yoko; Mertes, K. M.; Sarachik, M. P.; Agladze, N. I.; Sievers, A. J.; Rumberger, E. M.; Hendrickson, D. N.; Christou, G.

2004-03-01

The transmission spectra of both powder samples and assemblies of single crystals of Mn_12-acetate were measured in the far infrared region (2.0 - 20 cm-1) using a Fourier transform technique. The energies of the observed aborption lines agree with those obtained by Mukhin et al. [1] using the backwards wave oscillator technique. The temperature dependence of the aborption lines, as well as the presence of additional absorption lines, will be discussed. [1] A. A. Mukhin, V. D. Travkin, A. K. Zvesdin, A. Caneschi, D. Gatteschi and R. Sessoli, Physica B 284-288 (2000) 1221-1222

Study of radioactivity levels in detergent powders samples by gamma spectroscopy

Directory of Open Access Journals (Sweden)

Ali A. Abojassim

2014-10-01

Full Text Available This study focuses on the evaluation of the natural radioactivity levels in ten samples of the detergent powders that available in Iraqi markets. We have determined the specific activities of uranium, thorium and potassium using gamma spectroscopy and calculation of radiation hazard indices. The results of the activities of radionuclides (238U, 232Th, 40K for detergent powders samples, are found that the 238U specific activities were varied from (11.489 ± 2.089 Bq/kg to (36.062 ± 2.478 Bq/kg, while the 232th specific activities were varied from (1.411 ± 0.609 Bq/kg to (9.272 ± 1.642 Bq/kg and 40K were varied from (8.189 ± 2.339 Bq/kg to (91.888 ± 4.164 Bq/kg. These values are always lower than those of raw materials, what is explained by the conservation of radioactive material throughout the manufacturing process. The radium equivalent activity Raeq, the external hazard index Hex and the internal hazard index Hin dose due to natural radioactivity estimated below the regulatory standard recommended which are (370 Bq/kg, 1 and 1 according to OECD 1979 and ICRP 2000, allows us to show that Detergent powders samples products are not contaminated by radioactivity, are healthy and do not have harmful radiological impact on the consumer.

Acid-base characteristics of powdered-activated-carbon surfaces

Energy Technology Data Exchange (ETDEWEB)

Reed, B.E. (West Virginia Univ., Morgantown (United States)); Jensen, J.N.; Matsumoto, M.R. (State Univ. of New York, Buffalo (United States))

Adsorption of heavy metals onto activated carbon has been described using the surface-complex-formation (SCF) model, a chemical equilibrium model. The SCF model requires a knowledge of the amphoteric nature of activated carbon prior to metal adsorption modeling. In the past, a single-diprotic-acid-site model had been employed to describe the amphoteric nature of activated-carbon surfaces. During this study, the amphoteric nature of two powdered activated carbons were investigated, and a three-monoprotic site surface model was found to be a plausible alternative. The single-diprotic-acid-site and two-monoprotic-site models did not describe the acid-base behavior of the two carbons studied adequately. The two-diprotic site was acceptable for only one of the study carbons. The acid-base behavior of activated carbon surfaces seem to be best modeled as a series of weak monoprotic acids.

Low temperature synthesis of nanocrystalline lanthanum monoaluminate powders by chemical coprecipitation

Energy Technology Data Exchange (ETDEWEB)

Kuo, C.-L. [Department of Materials Science and Engineering, National Cheng Kung University, 1 Ta-Hsueh Road, Tainan 70101, Taiwan (China); Wang, C.-L. [Department of Materials Science and Engineering, I-Shou University, 1 Section 1, Hsueh-Cheng Road, Ta-Hsu Hsiang, Kaohsiung 840, Taiwan (China); Chen, T.-Y. [Department of Materials Science and Engineering, National Cheng Kung University, 1 Ta-Hsueh Road, Tainan 70101, Taiwan (China); Chen, G.-J. [Department of Materials Science and Engineering, I-Shou University, 1 Section 1, Hsueh-Cheng Road, Ta-Hsu Hsiang, Kaohsiung 840, Taiwan (China); Hung, I-M. [Department of Chemical Engineering and Materials Science, Yuan Ze University, 135 Yuan-Tung Road, Chungli, Taoyuan 320, Taiwan (China); Shih, C.-J. [Faculty of Fragrance and Cosmetics, Kaohsiung Medical University, 100 Shi-Chuan 1st Road, Kaohsiung 807, Taiwan (China)]. E-mail: CJShih@kmu.edu.tw; Fung, K.-Z. [Department of Materials Science and Engineering, National Cheng Kung University, 1 Ta-Hsueh Road, Tainan 70101, Taiwan (China)

2007-08-16

Nanocrystalline lanthanum monoaluminate (LaAlO{sub 3}) powders were prepared by chemical coprecipitation using 25 vol.% of NH{sub 4}OH, 0.05 M La(NO{sub 3}){sub 3}.6H{sub 2}O and 0.05 M Al(NO{sub 3}){sub 3}.9H{sub 2}O aqueous solutions as the starting materials. Fourier transform infrared spectroscopy (FT-IR), thermogravimetric and differential thermal analyses (TGA/DTA), X-ray diffraction (XRD), Raman spectrometry, specific surface area (BET) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and electron diffraction (ED) were utilized to characterize the LaAlO{sub 3} powders prepared by chemical coprecipitation. The crystallization temperature of the LaAlO{sub 3} precursor gels precipitated at pH 9 is estimated as 810 deg. C by TG/DTA. The XRD pattern of the LaAlO{sub 3} precursor gels precipitated at pH 8-12 and calcined at 700 deg. C for 6 h shows a broad arciform continuum exist between 24{sup o} and 32{sup o} and sharp peaks of LaAlO{sub 3} except the precursor gels precipitated at pH 9. For the LaAlO{sub 3} precursor gels precipitated at pH 9 and calcined at 700 deg. C for 6 h, the formation of the perovskite LaAlO{sub 3} phase occurs and the presence of crystalline impurities is not found. The crystallite size of LaAlO{sub 3} slightly increases from 37.8 to 41.5 nm with calcination temperature increasing from 700 to 900 deg. C for 6 h. The LaAlO{sub 3} powders prepared by chemical coprecipitation have a considerably large specific surface of 30 m{sup 2}/g. The relative density greater than 97% is obtained when these nanocrystalline LaAlO{sub 3} powders are sintered at 1550 deg. C for 2 h.

Plasma technology for powder particles

Energy Technology Data Exchange (ETDEWEB)

Kranz, E. (Technische Hochschule, Ilmenau (German Democratic Republic))

1983-03-01

A survey is given of principles and applications of plasma spraying and of powder transformation and generation in plasma considering spheroidization, grain size transformation, powder particle formation, powder reduction, and melting within the power range of 10/sup 3/ to 10/sup 7/ W. The products are applied in many industrial fields such as nuclear engineering, hard metal production, metallurgy, catalysis, and semiconductor techniques.

Predictive Simulation of Process Windows for Powder Bed Fusion Additive Manufacturing: Influence of the Powder Bulk Density.

Science.gov (United States)

Rausch, Alexander M; Küng, Vera E; Pobel, Christoph; Markl, Matthias; Körner, Carolin

2017-09-22

The resulting properties of parts fabricated by powder bed fusion additive manufacturing processes are determined by their porosity, local composition, and microstructure. The objective of this work is to examine the influence of the stochastic powder bed on the process window for dense parts by means of numerical simulation. The investigations demonstrate the unique capability of simulating macroscopic domains in the range of millimeters with a mesoscopic approach, which resolves the powder bed and the hydrodynamics of the melt pool. A simulated process window reveals the influence of the stochastic powder layer. The numerical results are verified with an experimental process window for selective electron beam-melted Ti-6Al-4V. Furthermore, the influence of the powder bulk density is investigated numerically. The simulations predict an increase in porosity and surface roughness for samples produced with lower powder bulk densities. Due to its higher probability for unfavorable powder arrangements, the process stability is also decreased. This shrinks the actual parameter range in a process window for producing dense parts.

Minimum ignition energy of nano and micro Ti powder in the presence of inert nano TiO₂ powder.

Science.gov (United States)

Chunmiao, Yuan; Amyotte, Paul R; Hossain, Md Nur; Li, Chang

2014-06-15

The inerting effect of nano-sized TiO2 powder on ignition sensitivity of nano and micro Ti powders was investigated with a Mike 3 apparatus. "A little is not good enough" is also suitable for micro Ti powders mixed with nano-sized solid inertants. MIE of the mixtures did not significantly increase until the TiO2 percentage exceeded 50%. Nano-sized TiO2 powders were ineffective as an inertant when mixed with nano Ti powders, especially at higher dust loadings. Even with 90% nano TiO2 powder, mixtures still showed high ignition sensitivity because the statistic energy was as low as 2.1 mJ. Layer fires induced by ignited but unburned metal particles may occur for micro Ti powders mixed with nano TiO2 powders following a low level dust explosion. Such layer fires could lead to a violent dust explosion after a second dispersion. Thus, additional attention is needed to prevent metallic layer fires even where electric spark potential is low. In the case of nano Ti powder, no layer fires were observed because of less flammable material involved in the mixtures investigated, and faster flame propagation in nanoparticle clouds. Copyright © 2014 Elsevier B.V. All rights reserved.

Ultrasonic wave propagation in powders

Science.gov (United States)

Al-Lashi, R. S.; Povey, M. J. W.; Watson, N. J.

2018-05-01

Powder clumps (cakes) has a significant effect on the flowability and stability of powders. Powder caking is mainly caused by moisture migration due to wetting and environmental (temperature and humidity) changes. The process of moisture migration caking involves creating liquid bridges between the particles during condensation which subsequently harden to form solid bridges. Therefore, an effective and reliable technique is required to quantitatively and non-invasively monitor caking kinetics and effective stiffness. This paper describes two ultrasonic instruments (ultrasonic velocity pulse and airborne ultrasound systems) that have been used to monitor the caking phenomenon. Also, it discusses the relationship between the ultrasonic velocity and attenuation measurements and tracking caking kinetics and the effective stiffness of powders.

Effect of surface energy on powder compactibility.

Science.gov (United States)

Fichtner, Frauke; Mahlin, Denny; Welch, Ken; Gaisford, Simon; Alderborn, Göran

2008-12-01

The influence of surface energy on the compactibility of lactose particles has been investigated. Three powders were prepared by spray drying lactose solutions without or with low proportions of the surfactant polysorbate 80. Various powder and tablet characterisation procedures were applied. The surface energy of the powders was characterized by Inverse Gas Chromatography and the compressibility of the powders was described by the relationship between tablet porosity and compression pressure. The compactibility of the powders was analyzed by studying the evolution of tablet tensile strength with increasing compaction pressure and porosity. All powders were amorphous and similar in particle size, shape, and surface area. The compressibility of the powders and the microstructure of the formed tablets were equal. However, the compactibility and dispersive surface energy was dependent of the composition of the powders. The decrease in tablet strength correlated to the decrease in powder surface energy at constant tablet porosities. This supports the idea that tablet strength is controlled by formation of intermolecular forces over the areas of contact between the particles and that the strength of these bonding forces is controlled by surface energy which, in turn, can be altered by the presence of surfactants.

The contribution to the modal analysis using an infrared camera

Directory of Open Access Journals (Sweden)

Dekys Vladimír

2018-01-01

Full Text Available The paper deals with modal analysis using an infrared camera. The test objects were excited by the modal exciter with narrowband noise and the response was registered as a frame sequence by the high speed infrared camera FLIR SC7500. The resonant frequencies and the modal shapes were determined from the infrared spectrum recordings. Lock-in technology has also been used. The experimental results were compared with calculated natural frequencies and modal shapes.

Removal of Cu (II) ions from aqueous solutions by turmeric powder

International Nuclear Information System (INIS)

Qayoom, A.; Kazmi, S.A.; Rafiq, N.

2009-01-01

Copper is an essential nutrient, but it is toxic at high intake levels. The presence of copper(II) ions causes serious toxicological concerns, it is usually known to deposit in brain, skin, liver, pancreas and myocardium. In this work the ability of turmeric to remove copper (II) ions from aqueous solution was studied. Adsorption of metals ions by turmeric powder may be used as a natural remedy for sequestration of toxic metals which are ingested through daily food intake It was found that adsorption increased with increasing contact time, pH, temperature, adsorbent dose. The equilibrium data were satisfactorily described by Freundlich isotherm model. Adsorption of Cu (II) by turmeric powder was followed by pseudo 2/sub nd/ order kinetics. (author)

Influence of Waste Brick Powder in the Mechanical Properties of Recycled Aggregate Concrete

Directory of Open Access Journals (Sweden)

Viviana Letelier

2018-03-01

Full Text Available Brick and concrete are the main materials contributing to demolition and construction waste. Considering this precedent, the effects of using both residuals in medium strength concretes are analyzed. Waste brick powder is used as a cement replacement in three different levels: 5%, 10%, and 15%, and it is tested in concretes with no recycled aggregates and concretes with 30% of recycled coarse aggregates replacing natural ones. The compressive strength, the flexural strength, and modulus of elasticity are calculated and compared to a control concrete with no brick powder and no recycled aggregates. The effects of the simultaneous use of both residuals on the physical properties of the recycled concrete are highlighted. Results show that 15% of cement can be replaced by waste brick powder together with 30% of recycled aggregates without suffering significant losses in the strength of the final material when compared to a control concrete.

Microwave reflection properties of planar anisotropy Fe50Ni50 powder/paraffin composites

International Nuclear Information System (INIS)

Wei Jian-Qiang; Zhang Zhao-Qi; Han Rui; Wang Tao; Li Fa-Shen

2012-01-01

The reflection properties of planar anisotropy Fe 50 Ni 50 powder/paraffin composites have been studied in the microwave frequency range. The permeability of Fe 50 Ni 50 powder/paraffin composites is greatly enhanced by introducing the planar anisotropy, and can be further enhanced by using a rotational orientation method. The complex permeability can be considered as the superposition of two types of magnetic resonance. The resonance peak at high frequency is attributed to the natural resonance, while the peak at low frequency is attributed to the domain-wall resonance. The simulated results of the microwave reflectivity show that the matching thickness, peak frequency, permeability, and permittivity are closely related to the quarter wavelength matching condition. The Fe 50 Ni 50 powder/paraffin composites can be attractive candidates for thinner microwave absorbers in the L-band (1–2 GHz). (condensed matter: electronic structure, electrical, magnetic, and optical properties)

Safety consideration when handling metal powders

CSIR Research Space (South Africa)

Benson, JM

2012-03-01

Full Text Available to some form of irritation or allergic reaction (e.g. dermatitis). In the case of nano-powders, the particles can penetrate the skin and become absorbed into cells in various parts of the body, including the brain � Eye contact, resulting in a... powders, and thus data is often limited to various ailments that have been reported for people working with that particular powder (amongs other things). There are three ways that powders can interact with the body: � Skin contact, which may lead...

Facile synthesis of Curcuma longa tuber powder engineered metal nanoparticles for bioimaging applications

Science.gov (United States)

Sankar, Renu; Rahman, Pattanathu K. S. M.; Varunkumar, Krishnamoorthy; Anusha, Chidambaram; Kalaiarasi, Arunachalam; Shivashangari, Kanchi Subramanian; Ravikumar, Vilwanathan

2017-02-01

Nanomaterials based fluorescent agents are rapidly becoming significant and promising transformative tools for improving medical diagnostics for extensive in vivo imaging modalities. Compared with conventional fluorescent agents, nano-fluorescence has capabilities to improve the in vivo detection and enriched targeting efficiencies. In our laboratory we synthesized fluorescent metal nanoparticles of silver, copper and iron using Curcuma longa tuber powder by simple reduction. The physicochemical properties of the synthesized metal nanoparticles were attained using UV-visible spectrophotometry, scanning electron microscopy with EDAX spectroscopy, dynamic light scattering, Fourier-transform infrared spectroscopy and X-ray diffraction. The Curcuma longa tuber powder has one of the bioactive compound Curcumin might act as a capping agent during the synthesis of nanoparticles. The synthesized metal nanoparticles fluorescence property was confirmed by spectrofluorometry. When compared with copper and iron nanoparticles the silver nanoparticles showed high fluorescence intensity under spectrofluorometry. Moreover, in vitro cell images of the silver nanoparticles in A549 cell lines also correlated with the results of spectrofluorometry. These silver nanoparticles show inspiring cell-imaging applications. They enter into cells without any further modifications, and the fluorescence property can be utilized for fluorescence-based cell imaging applications.

Effect of surface coating with magnesium stearate via mechanical dry powder coating approach on the aerosol performance of micronized drug powders from dry powder inhalers.

Science.gov (United States)

Zhou, Qi Tony; Qu, Li; Gengenbach, Thomas; Larson, Ian; Stewart, Peter J; Morton, David A V

2013-03-01

The objective of this study was to investigate the effect of particle surface coating with magnesium stearate on the aerosolization of dry powder inhaler formulations. Micronized salbutamol sulphate as a model drug was dry coated with magnesium stearate using a mechanofusion technique. The coating quality was characterized by X-ray photoelectron spectroscopy. Powder bulk and flow properties were assessed by bulk densities and shear cell measurements. The aerosol performance was studied by laser diffraction and supported by a twin-stage impinger. High degrees of coating coverage were achieved after mechanofusion, as measured by X-ray photoelectron spectroscopy. Concomitant significant increases occurred in powder bulk densities and in aerosol performance after coating. The apparent optimum performance corresponded with using 2% w/w magnesium stearate. In contrast, traditional blending resulted in no significant changes in either bulk or aerosolization behaviour compared to the untreated sample. It is believed that conventional low-shear blending provides insufficient energy levels to expose host micronized particle surfaces from agglomerates and to distribute guest coating material effectively for coating. A simple ultra-high-shear mechanical dry powder coating step was shown as highly effective in producing ultra-thin coatings on micronized powders and to substantially improve the powder aerosolization efficiency.

Chemical Composition and Antioxidant Properties of Powders Obtained from Different Plum Juice Formulations.

Science.gov (United States)

Michalska, Anna; Wojdyło, Aneta; Łysiak, Grzegorz P; Figiel, Adam

2017-01-17

Among popular crops, plum ( Prunus domestica L.) has received special attention due to its health-promoting properties. The seasonality of this fruit makes it impossible to consume it throughout the year, so new products in a powder form may offer an alternative to fresh consumption and may be used as high-quality natural food ingredients. A 100% plum (cultivar "Valor") juice was mixed with three different concentrations of maltodextrin or subjected to sugars removal by amberlite-XAD column, and dried using the freeze, spray, and vacuum (40, 60, and 80 °C) drying techniques. The identification and quantification of phenolic acids, flavonols, and anthocyanins in plum powders was performed by LC-MS QTof and UPLC-PDA, respectively. l-ascorbic acid, hydroxymethylfurfural, and antioxidant capacity were measured by the Trolox equivalent antioxidant capacity (TEAC) ABTS and ferric reducing antioxidant potential (FRAP) methods in order to compare the influence of the drying methods on product quality. The results indicated that the profile of polyphenolic compounds in the plum juice powders significantly differed from the whole plum powders. The drying of a sugar free plum extract resulted in higher content of polyphenolic compounds, l-ascorbic acid and antioxidant capacity, but lower content of hydroxymethylfurfural, regardless of drying method applied. Thus, the formulation of plum juice before drying and the drying method should be carefully selected in order to obtain high-quality powders.

Baking Powder Wars

OpenAIRE

Civitello, Linda

2017-01-01

How did a mid-nineteenth century American invention, baking powder, replace yeast as a leavening agent and create a culinary revolution as profound as the use of yeast thousands of years ago?The approach was two-pronged and gendered: business archives, U.S. government records and lawsuits revealed how baking powder was created, marketed, and regulated. Women’s diaries and cookbooks—personal, corporate, community, ethnic—from the eighteenth century to internet blogs showed the use women made o...

PRODUCTION OF POROUS POWDER MATERIALS OF SPHERICAL POWDERS OF CORROSION-RESISTANT STEEL

Directory of Open Access Journals (Sweden)

V. N. Kovalevskij

2012-01-01

Full Text Available Production of porous powder materials from spherical powders of corrosion-resistant steel 12Х18н10Т with formation at low pressures 120–140 mpa in the mold with the subsequent activated sintering became possible due to increase of duration of process of spattering and formation of condensate particles (Si–C or (Mo–Si on surface.

Comparison of blueberry powder produced via foam-mat freeze-drying versus spray-drying: evaluation of foam and powder properties.

Science.gov (United States)

Darniadi, Sandi; Ho, Peter; Murray, Brent S

2018-03-01

Blueberry juice powder was developed via foam-mat freeze-drying (FMFD) and spray-drying (SD) via addition of maltodextrin (MD) and whey protein isolate (WPI) at weight ratios of MD/WPI = 0.4 to 3.2 (with a fixed solids content of 5 wt% for FMFD and 10 wt% for SD). Feed rates of 180 and 360 mL h -1 were tested in SD. The objective was to evaluate the effect of the drying methods and carrier agents on the physical properties of the corresponding blueberry powders and reconstituted products. Ratios of MD/WPI = 0.4, 1.0 and 1.6 produced highly stable foams most suitable for FMFD. FMFD gave high yields and low bulk density powders with flake-like particles of large size that were also dark purple with high red values. SD gave low powder recoveries. The powders had higher bulk density and faster rehydration times, consisting of smooth, spherical and smaller particles than in FMFD powders. The SD powders were bright purple but less red than FMFD powders. Solubility was greater than 95% for both FMFD and SD powders. The FMFD method is a feasible method of producing blueberry juice powder and gives products retaining more characteristics of the original juice than SD. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

[Advances in studies on bear bile powder].

Science.gov (United States)

Zhou, Chao-fan; Gao, Guo-jian; Liu, Ying

2015-04-01

In this paper, a detailed analysis was made on relevant literatures about bear bile powder in terms of chemical component, pharmacological effect and clinical efficacy, indicating bear bile powder's significant pharmacological effects and clinical application in treating various diseases. Due to the complex composition, bear bile powder is relatively toxic. Therefore, efforts shall be made to study bear bile powder's pharmacological effects, clinical application, chemical composition and toxic side-effects, with the aim to provide a scientific basis for widespread reasonable clinical application of bear bile powder.

21 CFR 73.2645 - Aluminum powder.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Aluminum powder. 73.2645 Section 73.2645 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2645 Aluminum powder. (a) Identity and specifications. The color additive aluminum powder shall conform in identity and specifications to the requirements of...

CLAY SOIL STABILISATION USING POWDERED GLASS

Directory of Open Access Journals (Sweden)

J. OLUFOWOBI

2014-10-01

Full Text Available This paper assesses the stabilizing effect of powdered glass on clay soil. Broken waste glass was collected and ground into powder form suitable for addition to the clay soil in varying proportions namely 1%, 2%, 5%, 10% and 15% along with 15% cement (base by weight of the soil sample throughout. Consequently, the moisture content, specific gravity, particle size distribution and Atterberg limits tests were carried out to classify the soil using the ASSHTO classification system. Based on the results, the soil sample obtained corresponded to Group A-6 soils identified as ‘fair to poor’ soil type in terms of use as drainage and subgrade material. This justified stabilisation of the soil. Thereafter, compaction, California bearing ratio (CBR and direct shear tests were carried out on the soil with and without the addition of the powdered glass. The results showed improvement in the maximum dry density values on addition of the powdered glass and with corresponding gradual increase up to 5% glass powder content after which it started to decrease at 10% and 15% powdered glass content. The highest CBR values of 14.90% and 112.91% were obtained at 5% glass powder content and 5mm penetration for both the unsoaked and soaked treated samples respectively. The maximum cohesion and angle of internal friction values of 17.0 and 15.0 respectively were obtained at 10% glass powder content.

CVD carbon powders modified by ball milling

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Kazmierczak Tomasz

2015-09-01

Full Text Available Carbon powders produced using a plasma assisted chemical vapor deposition (CVD methods are an interesting subject of research. One of the most interesting methods of synthesizing these powders is using radio frequency plasma. This method, originally used in deposition of carbon films containing different sp2/sp3 ratios, also makes possible to produce carbon structures in the form of powder. Results of research related to the mechanical modification of these powders have been presented. The powders were modified using a planetary ball mill with varying parameters, such as milling speed, time, ball/powder mass ratio and additional liquids. Changes in morphology and particle sizes were measured using scanning electron microscopy and dynamic light scattering. Phase composition was analyzed using Raman spectroscopy. The influence of individual parameters on the modification outcome was estimated using statistical method. The research proved that the size of obtained powders is mostly influenced by the milling speed and the amount of balls. Powders tend to form conglomerates sized up to hundreds of micrometers. Additionally, it is possible to obtain nanopowders with the size around 100 nm. Furthermore, application of additional liquid, i.e. water in the process reduces the graphitization of the powder, which takes place during dry milling.

Shock diffraction in alumina powder

International Nuclear Information System (INIS)

Venz, G.; Killen, P.D.; Page, N.W.

1996-01-01

In order to produce complex shaped components by dynamic compaction of ceramic powders detailed knowledge of their response under shock loading conditions is required. This work attempts to provide data on release effects and shock attenuation in 1 μm and 5 μm α-alumina powders which were compacted to between 85 % and 95 % of the solid phase density by the impact of high velocity steel projectiles. As in previous work, the powder was loaded into large cylindrical dies with horizontal marker layers of a contrasting coloured powder to provide a record of powder displacement in the recovered specimens. After recovery and infiltration with a thermosetting resin the specimens were sectioned and polished to reveal the structure formed by the passage of the projectile and shock wave. Results indicate that the shock pressures generated were of the order of 0.5 to 1.4 GPa and higher, with shock velocities and sound speeds in the ranges 650 to 800 m/s and 350 to 400 m/s respectively

Zirconia powders production by precipitation: state-of-art review; Producao de pos de zirconia por precipitacao - revisao do estado da arte

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Ana Paula Almeida de; Torem, Mauricio Leonardo [Pontificia Univ. Catolica do Rio de Janeiro, RJ (Brazil). Dept. de Ciencia dos Materiais e Metalurgia

1994-12-31

The important role played by zirconia in advanced ceramics can be attributed to its excellent wear and corrosion resistance and refractory character. The polymorphic nature of zirconia made the controlled addition of stabilizing oxides or the constraining effect of a dense ceramics matrix necessary to maintain high parameters had a significant influence on powder properties and on compacted powder behaviour in sintering. Particle shape and size, purity and crystalline structure were specially influenced by precipitation parameters. Therefore, this work presented a review of the state of the art in zirconia powder production and in the recent research on precipitation of that powder. (author) 15 refs., 5 figs., 2 tabs.

21 CFR 73.1645 - Aluminum powder.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Aluminum powder. 73.1645 Section 73.1645 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1645 Aluminum powder. (a) Identity. (1) The color additive aluminum powder shall be composed of finely divided particles of aluminum prepared from virgin aluminum. It...

21 CFR 73.2647 - Copper powder.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Copper powder. 73.2647 Section 73.2647 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2647 Copper powder. (a) Identity and specifications. The color additive copper powder shall conform in identity and specifications to the requirements of § 73...

Synthesis and characterization of natural hydroxyapatite (recycled) composites with titania

International Nuclear Information System (INIS)

Mendes Filho, Antonio Alves; Gouveia, Vitor Jose Pinto; Pereira, Renato Alves; Araujo, Fernando Gabriel da Silva; Sousa, Camila Mateus de

2010-01-01

Natural hydroxyapatite biphasic ceramics (recycled) with titania (TiO_2-Hap) were studied in this work. For the formation of such ceramic the powders were mixed natural hydroxyapatite obtained from veal bone by the hydrothermal method with titania (TiO_2), forming the composites H9T1. The powders, manually homogenized, were conformed in pellet and sintered at temperatures between 1200 and 1400 deg C The ceramic bodies were characterized by XRD and SEM/EDS. The initial results were not satisfactory and require new studies. (author)

Effect of additives on the orientation of magnetic Sr-ferrite powders in powder injection molded compacts

Energy Technology Data Exchange (ETDEWEB)

Cho, T.S. [Sangju National Unviersity, Sangju (Korea); Jeung, W.Y. [Korea Institute of Science and Technology, Seoul (Korea)

2001-03-01

The effect of additives on the orientation of magnetic Sr-ferrite powders has been studied during powder injection molding under applied magnetic field for fabricating multi=pole anisotropic sintered Sr-ferrite magnets. The orientation of the Sr-ferrite powders depends sensitively on the fluidity of powder-binder mixture, related to the binder additives and the injection molding temperature, and the magnetic field intensity. The orientation of Sr-ferrite powders is good for the compacts with stearic acid added in the binder system of paraffin wax/ carnauba wax/HDPE, but it is poor of the compacts with silane coupling agent added. The orientation of sr-ferrites higher than 80% is achieved at the following useful conditions; apparent viscosity lower than 2500 poise in 1000 sec {sup -1} shear rate and applied magnetic field higher than 4 kOe. (author). 15 refs., 1 tab., 6 figs.

Hydrothermal treatment of coprecipitated YSZ powders

International Nuclear Information System (INIS)

Arakaki, Alexander Rodrigo; Yoshito, Walter Kenji; Ussui, Valter; Lazar, Dolores Ribeiro Ricci

2009-01-01

Zirconia stabilized with 8.5 mol% yttria (YSZ) were synthesized by coprecipitation and resulting gels were hydrothermally treated at 200°C and 220 PSI for 4, 8 and 16 hours. Products were oven dried at 70°C for 24 hours, uniaxially pressed as pellets and sintered at 1500 °C for 1 hour. Powders were characterized for surface area with N 2 gas adsorption, X-ray diffraction, laser diffraction granulometric analysis and scanning and transmission electronic microscopy. Density of ceramics was measured by an immersion method based on the Archimedes principle. Results showed that powders dried at 70°C are amorphous and after treatment has tetragonal/cubic symmetry. Surface area of powders presented a significant reduction after hydrothermal treatment. Ceramics prepared from hydrothermally treated powders have higher green density but sintered pellets are less dense when compared to that made with powders calcined at 800°C for 1 hour due to the agglomerate state of powders. Solvothermal treatment is a promising procedure to enhance density. (author)

Cheese powder as an ingredient in emulsion sausages

DEFF Research Database (Denmark)

Chen, Xiang; Ruiz Carrascal, Jorge; Petersen, Mikael Agerlin

2017-01-01

Different types of cheese powder were added to meat emulsion sausages in order to address its influence on chemical composition, volatile compounds profile and sensory properties, and its potential to reduce salt content through boosting saltiness. Addition of cheese powder to emulsion sausages...... modified their profile of volatile compounds. Blue cheese increased some ketones, alcohols, and esters, while brown cheese brought typical Maillard reaction compounds. Overall, addition of cheese powders to sausages enhanced the intensity of flavour traits. A mixture of hard and blue cheese powder showed...... the highest effect on boosting saltiness, while brown cheese powder showed the strongest umami and meat flavour boosting effect, and sausages with added blue cheese powder showed a more intense aftertaste. Hardness significantly increased due to the addition of blue cheese powder. Addition of cheese powder...

Spheroidization of glass powders for glass ionomer cements.

Science.gov (United States)

Gu, Y W; Yap, A U J; Cheang, P; Kumar, R

2004-08-01

Commercial angular glass powders were spheroidized using both the flame spraying and inductively coupled radio frequency plasma spraying techniques. Spherical powders with different particle size distributions were obtained after spheroidization. The effects of spherical glass powders on the mechanical properties of glass ionomer cements (GICs) were investigated. Results showed that the particle size distribution of the glass powders had a significant influence on the mechanical properties of GICs. Powders with a bimodal particle size distribution ensured a high packing density of glass ionomer cements, giving relatively high mechanical properties of GICs. GICs prepared by flame-spheroidized powders showed low strength values due to the loss of fine particles during flame spraying, leading to a low packing density and few metal ions reacting with polyacrylic acid to form cross-linking. GICs prepared by the nano-sized powders showed low strength because of the low bulk density of the nano-sized powders and hence low powder/liquid ratio of GICs.

2014 - Color & Infrared - Northeastern Vermont (0.5m)

Data.gov (United States)

Vermont Center for Geographic Information — (Link to Metadata) This metadata record describes the acquisition and production of natural color and color infrared digital ground orthoimagery covering a portion...

Infiltration Behavior Of Mechanical Alloyed 75 wt% Cu-25 wt% WC Powders Into Porous WC Compacts

Directory of Open Access Journals (Sweden)

Şelte A.

2015-06-01

Full Text Available In this work infiltration behavior of mechanical alloyed 75 wt% Cu – 25 wt% WC powders into porous WC compacts were studied. Owing to their ductile nature, initial Cu powders were directly added to mechanical alloying batch. On the other hand initial WC powders were high energy milled prior to mechanical alloying. Contact infiltration method was selected for densification and compacts prepared from processed powders were infiltrated into porous WC bodies. After infiltration, samples were characterized via X-Ray diffraction studies and microstructural evaluation of the samples was carried out via scanning electron microscopy observations. Based on the lack of solubility between WC and Cu it was possible to keep fine WC particles in Cu melt since solution reprecipitation controlled densification is hindered. Also microstructural characterizations via scanning electron microscopy confirmed that the transport of fine WC fraction from infiltrant to porous WC skeleton can be carried out via Cu melt flow during infiltration.

Teaching physics and understanding infrared thermal imaging

Science.gov (United States)

Vollmer, Michael; Möllmann, Klaus-Peter

2017-08-01

Infrared thermal imaging is a very rapidly evolving field. The latest trends are small smartphone IR camera accessories, making infrared imaging a widespread and well-known consumer product. Applications range from medical diagnosis methods via building inspections and industrial predictive maintenance etc. also to visualization in the natural sciences. Infrared cameras do allow qualitative imaging and visualization but also quantitative measurements of the surface temperatures of objects. On the one hand, they are a particularly suitable tool to teach optics and radiation physics and many selected topics in different fields of physics, on the other hand there is an increasing need of engineers and physicists who understand these complex state of the art photonics systems. Therefore students must also learn and understand the physics underlying these systems.

Morphology control and negative thermal expansion in cubic ZrWMoO8 powders

International Nuclear Information System (INIS)

Liu, Qinqin; Yang, Juan; Sun, Xiujuan; Cheng, Xiaonong

2008-01-01

Cubic ZrWMoO 8 powders with rod-like aggregate and thin fasciculus-like and flower-like rod cluster morphologies have been successfully fabricated with different amounts of (NH 4 ) 2 HPO 4 as surfactant using a hydrothermal method. X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and differential scanning calorimetry were utilized to investigate the influence of the addition of (NH 4 ) 2 HPO 4 on the crystallization process and crystal morphology of the resulting products. The results show that the purity and the thermal expansion property of the resulting products are not influenced by the addition of (NH 4 ) 2 HPO 4 . The cubic ZrWMoO 8 powders with both rod-like aggregate and flower-like rod cluster morphologies show a positive thermal expansion property in the temperature range from room temperature to 120 C, while they show a negative thermal expansion property in the temperature range from 120 C to 700 C. The abnormal thermal expansion property of cubic ZrWMoO 8 below 120 C is caused by the presence of water molecules. Investigations also show that the essence of the different morphologies of the ZrWMoO 8 particles obtained is the result of the different aggregation modes of the nanorods, which act as nuclei, and the corresponding aggregation process is dominated by the addition of (NH 4 ) 2 HPO 4 and its amount. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Natural zeolite reactivity towards ozone: The role of compensating cations

Energy Technology Data Exchange (ETDEWEB)

Valdes, Hector, E-mail: hvaldes@ucsc.cl [Laboratorio de Tecnologias Limpias (F. Ingenieria), Universidad Catolica de la Santisima Concepcion, Alonso de Ribera 2850, Concepcion (Chile); Alejandro, Serguei; Zaror, Claudio A. [Departamento de Ingenieria Quimica (F. Ingenieria), Universidad de Concepcion, Concepcion (Chile)

2012-08-15

Highlights: Black-Right-Pointing-Pointer Chemical and thermal treatment enhances catalytic activity of natural zeolite. Black-Right-Pointing-Pointer Modified natural zeolite exhibits high stability after thermal treatment. Black-Right-Pointing-Pointer Reducing the compensating cation content leads to an increase on ozone abatement. Black-Right-Pointing-Pointer Surface active atomic oxygen was detected using the DRIFT technique. Black-Right-Pointing-Pointer The highest reactivity toward ozone was performed by NH4Z3 zeolite sample. - Abstract: Among indoor pollutants, ozone is recognised to pose a threat to human health. Recently, low cost natural zeolites have been applied as alternative materials for ozone abatement. In this work, the effect of compensating cation content of natural zeolite on ozone removal is studied. A Chilean natural zeolite is used here as starting material. The amount of compensating cations in the zeolite framework was modified by ion exchange using an ammonium sulphate solution (0.1 mol L{sup -1}). Characterisation of natural and modified zeolites were performed by X-ray powder diffraction (XRD), nitrogen adsorption at 77 K, elemental analysis, X-ray fluorescence (XRF), thermogravimetric analysis coupled with mass spectroscopy (TGA-MS), and temperature-programmed desorption of ammonia (NH{sub 3}-TPD). Ozone adsorption and/or decomposition on natural and modified zeolites were studied by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Results show that the zeolite compensating cation content affects ozone interaction with zeolite active sites. Ammonium ion-exchange treatments followed by thermal out-gassing at 823 K, reduces ozone diffusion resistance inside the zeolite framework, increasing ozone abatement on zeolite surface active sites. Weak and strong Lewis acid sites of zeolite surface are identified here as the main active sites responsible of ozone removal.

Preparation and properties of thermal insulation coatings with a sodium stearate-modified shell powder as a filler

Science.gov (United States)

Tang, Qiang; Zhang, Ya-mei; Zhang, Pei-gen; Shi, Jin-jie; Tian, Wu-bian; Sun, Zheng-ming

2017-10-01

Waste shell stacking with odor and toxicity is a serious hazard to our living environment. To make effective use of the natural resources, the shell powder was applied as a filler of outdoor thermal insulation coatings. Sodium stearate (SS) was used to modify the properties of shell powder to reduce its agglomeration and to increase its compatibility with the emulsion. The oil absorption rate and the spectrum reflectance of the shell powder show that the optimized content of SS as a modifier is 1.5wt%. The total spectrum reflectance of the coating made with the shell powder that is modified at this optimum SS content is 9.33% higher than that without any modification. At the optimum SS content of 1.5wt%, the thermal insulation of the coatings is improved by 1.0°C for the cement mortar board and 1.6°C for the steel plate, respectively. The scouring resistance of the coating with the 1.5wt% SS-modified shell powder is three times that of the coating without modification.

Development of nondestructive detection method for adulterated powder products using Raman spectroscopy and partial least squares regression

Energy Technology Data Exchange (ETDEWEB)

Lee, Sang Dae; Lohumi, Santosh; Cho, Byoung Kwan [Dept. of Biosystems Machinery Engineering, Chungnam National University, Daejeon (Korea, Republic of); Kim, Moon Sung [United States Department of Agriculture Agricultural Research Service, Washington (United States); Lee, Soo Hee [Life and Technology Co.,Ltd., Hwasung (Korea, Republic of)

2014-08-15

This study was conducted to develop a non-destructive detection method for adulterated powder products using Raman spectroscopy and partial least squares regression(PLSR). Garlic and ginger powder, which are used as natural seasoning and in health supplement foods, were selected for this experiment. Samples were adulterated with corn starch in concentrations of 5-35%. PLSR models for adulterated garlic and ginger powders were developed and their performances evaluated using cross validation. The R{sup 2}{sub c} and SEC of an optimal PLSR model were 0.99 and 2.16 for the garlic powder samples, and 0.99 and 0.84 for the ginger samples, respectively. The variable importance in projection (VIP) score is a useful and simple tool for the evaluation of the importance of each variable in a PLSR model. After the VIP scores were taken pre-selection, the Raman spectrum data was reduced by one third. New PLSR models, based on a reduced number of wavelengths selected by the VIP scores technique, gave good predictions for the adulterated garlic and ginger powder samples.

Development of nondestructive detection method for adulterated powder products using Raman spectroscopy and partial least squares regression

International Nuclear Information System (INIS)

Lee, Sang Dae; Lohumi, Santosh; Cho, Byoung Kwan; Kim, Moon Sung; Lee, Soo Hee

2014-01-01

This study was conducted to develop a non-destructive detection method for adulterated powder products using Raman spectroscopy and partial least squares regression(PLSR). Garlic and ginger powder, which are used as natural seasoning and in health supplement foods, were selected for this experiment. Samples were adulterated with corn starch in concentrations of 5-35%. PLSR models for adulterated garlic and ginger powders were developed and their performances evaluated using cross validation. The R 2 c and SEC of an optimal PLSR model were 0.99 and 2.16 for the garlic powder samples, and 0.99 and 0.84 for the ginger samples, respectively. The variable importance in projection (VIP) score is a useful and simple tool for the evaluation of the importance of each variable in a PLSR model. After the VIP scores were taken pre-selection, the Raman spectrum data was reduced by one third. New PLSR models, based on a reduced number of wavelengths selected by the VIP scores technique, gave good predictions for the adulterated garlic and ginger powder samples.

Effect of powder geometry on densification

International Nuclear Information System (INIS)

Spasskij, M.R.; Spasskaya, I.A.; Shatalova, I.G.; Shchukin, E.D.

1979-01-01

The effect of particle shape and size composition on the processes of powder vibratory compacting is considered. Using microstress measurements in compacted structures of conglomerated and disintegrated tungsten powders as well as powder strength testing the existence of a zone of transition from a structural deformation to a plastic one has been shown. The formation of phase interparticle contacts of practically stable strength (approximately 5-6 dyn) is a characteristic feature of the zone. The width of the transition zone greatly depends upon geometrical powder properties; 55-65 % for conglomerated tungsten, 63-66 % for integrated tungsten

Research on Durability of Recycled Ceramic Powder Concrete

Science.gov (United States)

Chen, M. C.; Fang, W.; Xu, K. C.; Xie, L.

2017-06-01

Ceramic was ground into powder with 325 mesh and used to prepare for concrete. Basic mechanical properties, carbonation and chloride ion penetration of the concrete tests were conducted. In addition, 6-hour electric fluxes of recycled ceramic powder concrete were measured under loading. The results showed that the age strength of ceramics powder concrete is higher than that of the ordinary concrete and the fly ash concrete. The ceramic powder used as admixture would reduce the strength of concrete under no consideration of its impact factor; under consideration of the impact factor for ceramic powder as admixture, the carbonation resistance of ceramic powder concrete was significantly improved, and the 28 day carbonation depth of the ceramic powder concrete was only 31.5% of ordinary concrete. The anti-chloride-permeability of recycled ceramic powder concrete was excellent.

Simple process to fabricate nitride alloy powders

International Nuclear Information System (INIS)

Yang, Jae Ho; Kim, Dong-Joo; Kim, Keon Sik; Rhee, Young Woo; Oh, Jang-Soo; Kim, Jong Hun; Koo, Yang Hyun

2013-01-01

Uranium mono-nitride (UN) is considered as a fuel material [1] for accident-tolerant fuel to compensate for the loss of fissile fuel material caused by adopting a thickened cladding such as SiC composites. Uranium nitride powders can be fabricated by a carbothermic reduction of the oxide powders, or the nitriding of metal uranium. Among them, a direct nitriding process of metal is more attractive because it has advantages in the mass production of high-purity powders and the reusing of expensive 15 N 2 gas. However, since metal uranium is usually fabricated in the form of bulk ingots, it has a drawback in the fabrication of fine powders. The Korea Atomic Energy Research Institute (KAERI) has a centrifugal atomisation technique to fabricate uranium and uranium alloy powders. In this study, a simple reaction method was tested to fabricate nitride fuel powders directly from uranium metal alloy powders. Spherical powder and flake of uranium metal alloys were fabricated using a centrifugal atomisation method. The nitride powders were obtained by thermal treating the metal particles under nitrogen containing gas. The phase and morphology evolutions of powders were investigated during the nitriding process. A phase analysis of nitride powders was also part of the present work. KAERI has developed the centrifugal rotating disk atomisation process to fabricate spherical uranium metal alloy powders which are used as advanced fuel materials for research reactors. The rotating disk atomisation system involves the tasks of melting, atomising, and collecting. A nozzle in the bottom of melting crucible introduces melt at the center of a spinning disk. The centrifugal force carries the melt to the edge of the disk and throws the melt off the edge. Size and shape of droplets can be controlled by changing the nozzle size, the disk diameter and disk speed independently or simultaneously. By adjusting the processing parameters of the centrifugal atomiser, a spherical and flake shape

Infrared observations of AE Aquarii

Science.gov (United States)

Tanzi, E. G.; Chincarini, G.; Tarenghi, M.

1981-01-01

Broadband infrared observations of the cataclysmic variable AE Aquarii are reported. The observations were obtained in the J, H, K and L filters with the InSb photometer attached to the 1-m telescope of the European Southern Observatory. The infrared energy distribution observed from 0.35 to 3.5 microns for phase 0.5 suggests a spectral type of K5 V for the secondary and a distance to the system of approximately 70 pc if an absolute magnitude of 7.3 is assumed. Monitoring of the flux at 2.2 microns reveals a variability with an amplitude of approximately 0.3 magnitude over one third of the orbital period, the nature of which is under investigation.

Numerical study on the influence of aluminum on infrared radiation signature of exhaust plume

Science.gov (United States)

Zhang, Wei; Ye, Qing-qing; Li, Shi-peng; Wang, Ning-fei

2013-09-01

The infrared radiation signature of exhaust plume from solid propellant rockets has been widely mentioned for its important realistic meaning. The content of aluminum powder in the propellants is a key factor that affects the infrared radiation signature of the plume. The related studies are mostly on the conical nozzles. In this paper, the influence of aluminum on the flow field of plume, temperature distribution, and the infrared radiation characteristics were numerically studied with an object of 3D quadrate nozzle. Firstly, the gas phase flow field and gas-solid multi phase flow filed of the exhaust plume were calculated using CFD method. The result indicates that the Al203 particles have significant effect on the flow field of plume. Secondly, the radiation transfer equation was solved by using a discrete coordinate method. The spectral radiation intensity from 1000-2400 cm-1 was obtained. To study the infrared radiation characteristics of exhaust plume, an exceptional quadrate nozzle was employed and much attention was paid to the influences of Al203 particles in solid propellants. The results could dedicate the design of the divert control motor in such hypervelocity interceptors or missiles, or be of certain meaning to the improvement of ingredients of solid propellants.

Magnetization and 13C NMR spin-lattice relaxation of nanodiamond powder

Energy Technology Data Exchange (ETDEWEB)

Levin, E.M.; Fang, X.W.; Bud' ko, S.L.; Straszheim, W.E.; McCallum, R.W.; Schmidt-Rohr, K.

2008-02-15

The bulk magnetization at temperatures of 1.8-400 K and in magnetic fields up to 70 kOe, the ambient temperature {sup 13}C NMR spin-lattice relaxation, T{sub 1,c}, and the elemental composition of three nanodiamond powder samples have been studied. The total magnetization of nanodiamond can be explained in terms of contributions from (1) the diamagnetic effect of carbon, (2) the paramagnetic effect of unpaired electrons present in nanodiamond grains, and (3) ferromagnetic-like and (4) superparamagnetic contributions from Fe-containing particles detected in spatially resolved energy-dispersive spectroscopy. Contributions (1) and (2) are intrinsic to nanodiamond, while contributions (3) and (4) arise from impurities naturally present in detonation nanodiamond samples. {sup 13}C NMR T{sub 1,c} relaxation would be unaffected by the presence of the ferromagnetic particles with the bulk magnetization of {approx} 0.01 emu/g at 300 K. Thus, a reduction of T{sub 1,c} by 3 orders of magnitude compared to natural and synthetic microdiamonds confirms the presence of unpaired electrons in the nanodiamond grains. The spin concentration in nanodiamond powder corresponds to {approx}30 unpaired electrons per {approx}4.6 nm diameter nanodiamond grain.

MECHANICS OF DYNAMIC POWDER COMPACTION PROCESS

OpenAIRE

Nurettin YAVUZ

1996-01-01

In recent years, interest in dynamic compaction methods of metal powders has increased due to the need to improve compaction properties and to increase production rates of compacts. In this paper, review of dynamic and explosive compaction of metal powders are given. An attempt is made to get a better understanding of the compaction process with the mechanicis of powder compaction.

Standard test methods for chemical and mass spectrometric analysis of nuclear-grade gadolinium oxide (Gd2O3) powder

CERN Document Server

American Society for Testing and Materials. Philadelphia

2006-01-01

1.1 These test methods cover procedures for the chemical and mass spectrometric analysis of nuclear-grade gadolinium oxide powders to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Carbon by Direct CombustionThermal Conductivity C1408 Test Method for Carbon (Total) in Uranium Oxide Powders and Pellets By Direct Combustion-Infrared Detection Method Total Chlorine and Fluorine by Pyrohydrolysis Ion Selective Electrode C1502 Test Method for Determination of Total Chlorine and Fluorine in Uranium Dioxide and Gadolinium Oxide Loss of Weight on Ignition 7-13 Sulfur by CombustionIodometric Titration Impurity Elements by a Spark-Source Mass Spectrographic C761 Test Methods for Chemical, Mass Spectrometric, Spectrochemical,Nuclear, and Radiochemical Analysis of Uranium Hexafluoride C1287 Test Method for Determination of Impurities In Uranium Dioxide By Inductively Coupled Plasma Mass Spectrometry Gadolinium Content in Gadolinium Oxid...

Process Parameters on the Crystallization and Morphology of Hydroxyapatite Powders Prepared by a Hydrolysis Method

Science.gov (United States)

Wang, Moo-Chin; Hon, Min-Hsiung; Chen, Hui-Ting; Yen, Feng-Lin; Hung, I.-Ming; Ko, Horng-Huey; Shih, Wei-Jen

2013-07-01

The effects of process parameters on the crystallization and morphology of hydroxyapatite (Ca10(PO4)6(OH)2, HA) powders synthesized from dicalcium phosphate dihydrate (CaHPO4·2H2O, DCPD) using a hydrolysis method have been investigated. X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectra, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and selected area electron diffraction (SAED) were used to characterize the synthesized powders. When DCPD underwent hydrolysis in 2.5 NaOH solution (Na(aq)) at 303 K to 348 K (30 °C to 75 °C) for 1 hour, the XRD results revealed that HA was obtained for all the as-dried samples. The SEM morphology of the HA powders for DCPD hydrolysis produced at 348 K (75 °C) shows regular alignment and a short rod shape with a size of 200 nm in length and 50 nm in width. With DCPD hydrolysis in 2.5 M NaOH(aq) holding at 348 K (75 °C) for 1 to 24 hours, XRD results demonstrated that all samples were HA and no other phases could be detected. Moreover, the XRD results also show that all the as-dried powders still maintained the HA structure when DCPD underwent hydrolysis in 0.1 to 5 M NaOH(aq) at 348 K (75 °C) for 1 hour. Otherwise, the full transformation from HA to octa-calcium phosphate (OCP, Ca8H2(PO4)6·5H2O) occurred when hydrolysis happened in 10 M NaOH(aq). FT-IR spectra analysis revealed that some carbonated HA (Ca10(PO4)6(CO3), CHA) had formed. The SEM morphology results show that the 60 to 65 nm width of the uniformly long rods with regular alignment formed in the HA powder aggregates when DCPD underwent hydrolysis in 2.5 M NaOH(aq) at 348 K (75 °C) for 1 hour.

Recent advances in mid- and near-infrared spectroscopy with applications for research and teaching, focusing on petrochemistry and biotechnology relevant products

Science.gov (United States)

Heise, H. M.; Fritzsche, J.; Tkatsch, H.; Waag, F.; Karch, K.; Henze, K.; Delbeck, S.; Budde, J.

2013-11-01

Mid- and near-infrared spectroscopy is introduced as a versatile analytical method for characterizing liquid and solid chemicals as obtained from petrochemistry and biotechnology processes. Besides normal transmission measurements, special equipment with silver halide fiber-optic probes allowing efficient analysis based on mid-infrared attenuated total reflection, and an accessory for near-infrared diffuse reflection measurements, are presented. The latter technique can be used advantageously for powdered samples such as microalgae biomass and polysaccharides, as well as for different tissues such as meat samples. The advantages and disadvantages of both methods, which can be used for industrial process monitoring and chemical quality control applications, are discussed, and have been used in several research projects of BSc students within their degree course of bio- and nano-technologies of our University of Applied Sciences.

Recent advances in mid- and near-infrared spectroscopy with applications for research and teaching, focusing on petrochemistry and biotechnology relevant products

International Nuclear Information System (INIS)

Heise, H M; Fritzsche, J; Tkatsch, H; Waag, F; Karch, K; Henze, K; Delbeck, S; Budde, J

2013-01-01

Mid- and near-infrared spectroscopy is introduced as a versatile analytical method for characterizing liquid and solid chemicals as obtained from petrochemistry and biotechnology processes. Besides normal transmission measurements, special equipment with silver halide fiber-optic probes allowing efficient analysis based on mid-infrared attenuated total reflection, and an accessory for near-infrared diffuse reflection measurements, are presented. The latter technique can be used advantageously for powdered samples such as microalgae biomass and polysaccharides, as well as for different tissues such as meat samples. The advantages and disadvantages of both methods, which can be used for industrial process monitoring and chemical quality control applications, are discussed, and have been used in several research projects of BSc students within their degree course of bio- and nano-technologies of our University of Applied Sciences. (paper)

Active Thermography for the Detection of Defects in Powder Metallurgy Compacts

International Nuclear Information System (INIS)

Benzerrouk, Souheil; Ludwig, Reinhold; Apelian, Diran

2007-01-01

Active thermography is an established NDE technique that has become the method of choice in many industrial applications which require non-contact access to the parts under test. Unfortunately, when conducting on-line infrared (IR) inspection of powder metallic compacts, complications can arise due the generally low emissivity of metals and the thermally noisy environment typically encountered in manufacturing plants. In this paper we present results of an investigation that explores the suitability of active IR imaging of powder metallurgy compacts for the detection of surface and sub-surface defects in the pre-sinter state and in an on-line manufacturing setting to ensure complete quality assurance. Additional off-line tests can be carried out for statistical quality analyses. In this research, the IR imaging of sub-surface defects is based on a transient instrumentation approach that relies on an electric control system which synchronizes and monitors the thermal response due to an electrically generated heat source. Preliminary testing reveals that this newly developed pulsed thermography system can be employed for the detection of subsurface defects in green-state parts. Practical measurements agree well with theoretical predictions. The inspection approach being developed can be used for the testing of green-state compacts as they exit the compaction press at speeds of up to 1,000 parts per hour

Tantalum powder consolidation, modeling and properties

International Nuclear Information System (INIS)

Bingert, S.R.; Vargas, V.D.; Sheinberg, H.C.

1996-01-01

A systematic approach was taken to investigate the consolidation of tantalum powders. The effects of sinter time, temperature and ramp rate; hot isostatic pressing (HIP) temperature and time; and powder oxygen content on consolidation density, kinetics, microstructure, crystallographic texture, and mechanical properties have been evaluated. In general, higher temperatures and longer hold times resulted in higher density compacts with larger grain sizes for both sintering and HIP'ing. HIP'ed compacts were consistently higher in density than sintered products. The higher oxygen content powders resulted in finer grained, higher density HIP'ed products than the low oxygen powders. Texture analysis showed that the isostatically processed powder products demonstrated a near random texture. This resulted in isotropic properties in the final product. Mechanical testing results showed that the HIP'ed powder products had consistently higher flow stresses than conventionally produced plates, and the sintered compacts were comparable to the plate material. A micromechanics model (Ashby HIP model) has been employed to predict the mechanisms active in the consolidation processes of cold isostatic pressing (CIP), HIP and sintering. This model also predicts the density of the end product and whether grain growth should be expected under the applied processing conditions

Vacuum hot pressing of titanium-alloy powders

International Nuclear Information System (INIS)

Malik, R.K.

1975-01-01

Full or nearly full dense products of wrought-metal properties have been obtained by vacuum hot pressing (VHP) of several prealloyed Ti--6Al--4V powders including hydride, hydride/dehydride, and rotating electrode process (REP) spherical powder. The properties of billets VHP from Ti--6Al--4V hydride powder and from hydride/dehydride powders have been shown to be equivalent. The REP spherical powder billets processed by VHP or by hot isostatic pressing (HIP) resulted in equivalent tensile properties. The potential of VHP for fabrication of near net aircraft parts such as complex fittings and engine disks offers considerable cost savings due to reduced material and machining requirements

Chemical Composition and Antioxidant Properties of Powders Obtained from Different Plum Juice Formulations

Directory of Open Access Journals (Sweden)

Anna Michalska

2017-01-01

Full Text Available Among popular crops, plum (Prunus domestica L. has received special attention due to its health-promoting properties. The seasonality of this fruit makes it impossible to consume it throughout the year, so new products in a powder form may offer an alternative to fresh consumption and may be used as high-quality natural food ingredients. A 100% plum (cultivar “Valor” juice was mixed with three different concentrations of maltodextrin or subjected to sugars removal by amberlite-XAD column, and dried using the freeze, spray, and vacuum (40, 60, and 80 °C drying techniques. The identification and quantification of phenolic acids, flavonols, and anthocyanins in plum powders was performed by LC-MS QTof and UPLC-PDA, respectively. l-ascorbic acid, hydroxymethylfurfural, and antioxidant capacity were measured by the Trolox equivalent antioxidant capacity (TEAC ABTS and ferric reducing antioxidant potential (FRAP methods in order to compare the influence of the drying methods on product quality. The results indicated that the profile of polyphenolic compounds in the plum juice powders significantly differed from the whole plum powders. The drying of a sugar free plum extract resulted in higher content of polyphenolic compounds, l-ascorbic acid and antioxidant capacity, but lower content of hydroxymethylfurfural, regardless of drying method applied. Thus, the formulation of plum juice before drying and the drying method should be carefully selected in order to obtain high-quality powders.

Development of Wood Apple Shell (Feronia acidissima) Powder Biosorbent and Its Application for the Removal of Cd(II) from Aqueous Solution

OpenAIRE

Ch. Suresh; D. Harikisore Kumar Reddy; Yapati Harinath; B. Ramesh Naik; K. Seshaiah; Annareddy V. Ramana Reddy

2014-01-01

A biosorbent was prepared by using wood apple shell (WAS) powder and studied its application for the removal of Cd(II) from aqueous solution by a batch method. The biosorbent was characterized by infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and elemental analysis. WAS is principally made up of lignin and cellulose, containing functional groups such as alcoholic, ketonic, and carboxylic groups which can be involved in complexation reactions with Cd(II). The effect of...

Near-infrared spectroscopy (NIRS evaluation and regional analysis of Chinese faba bean (Vicia faba L.

Directory of Open Access Journals (Sweden)

Jiaojiao Wang

2014-02-01

Full Text Available To analyze the nutritional composition of faba bean (Vicia faba L. seed, estimation models were developed for protein, starch, oil, and total polyphenol using near infrared spectroscopy (NIRS. Two hundred and forty-four samples from twelve producing regions were measured in both milled powder and intact seed forms. Partial least squares (PLS regression was applied for model development. The model based on ground seed powder was generally superior to that based on the intact seed. The optimal seed powder-based models for protein, starch, and total polyphenol had coefficients of correlation (r2 of 0.97, 0.93 and 0.89, respectively. The relationship between nutrient contents and twelve producing areas was determined by two-step cluster analysis. Three distinct groupings were obtained with region-constituent features, i.e., Group 1 of high oil, Group 2 of high protein, and Group 3 of high starch as well as total polyphenol. The clustering accuracy was 79.5%. Moreover, the nutrition contents were affected by seeding date, longitude, latitude, and altitude of plant location. Cluster analysis revealed that the differences in the seed were strongly influenced by geographical factors.

Superconductors by powder metallurgy techniques

International Nuclear Information System (INIS)

Pickus, M.R.; Wang, J.L.F.

1976-05-01

Fabrication methods for Nb 3 Sn type compounds are described. Information is included on the Bell Telephone process, the General Electric tape process, superconductor stability, the bronze process, powder metallurgy multifilamentary tapes and wires, and current assessment of powder metallurgy superconducting wire

Far infrared supplement: Catalog of infrared observations, second edition

International Nuclear Information System (INIS)

Gezari, D.Y.; Schmitz, M.; Mead, J.M.

1988-08-01

The Far Infrared Supplement: Catalog of Infrared Observations summarizes all infrared astronomical observations at far infrared wavelengths (5 to 1000 microns) published in the scientific literature from 1965 through 1986. The Supplement list contain 25 percent of the observations in the full Catalog of Infrared Observations (CIO), and essentially eliminates most visible stars from the listings. The Supplement is thus more compact than the main catalog, and is intended for easy reference during astronomical observations. The Far Infrared Supplement (2nd Edition) includes the Index of Infrared Source Positions and the Bibliography of Infrared Astronomy for the subset of far infrared observations listed

Thermal and structural characterization of synthetic and natural nanocrystalline hydroxyapatite

International Nuclear Information System (INIS)

Sofronia, Ancuta M.; Baies, Radu; Anghel, Elena M.; Marinescu, Cornelia A.; Tanasescu, Speranta

2014-01-01

The aim of this work was to study the thermal stability on heating and to obtain the processing parameters of synthetic and bone-derived hydroxyapatite over temperatures between room temperature and 1400 °C by thermal analysis (thermogravimetry (TG)/differential scanning calorimetry (DSC) and thermo-mechanical analysis—TMA). Structural and surface modifications related to samples origin and calcination temperature were investigated by Fourier transformed infrared (FTIR) and Raman spectroscopy, X-ray diffraction (XRD) and BET method. FTIR spectra indicated that the organic constituents and carbonate are no longer present in the natural sample calcined at 800 °C. Raman spectra highlighted the decomposition products of the hydroxyapatite. The calcination treatment modifies the processes kinetics of the synthetic samples, being able to isolate lattice water desorption processes of decarbonization and the dehydroxylation processes. Shrinkage of calcined synthetic sample increases by 10% compared to uncalcined synthetic powder. From the TMA correlated with TG analysis and heat capacity data it can be concluded that sintering temperature of the synthetic samples should be chosen in the temperature range of the onset of dehydroxylation and the temperature at which oxyapatite decomposition begins. - Highlights: • Specific surface area of HA powder was reduced from 19.2 to 9.5 m 2 /g by calcination. • Raman spectra indicate the presence of B-type CO 3 group in HA synthetic samples. • The onset temperature of HA densification and dehydroxylation processes correspond. • Calcination of HA influences reactions kinetics with consequences on densification. • Shrinkage of calcined HA sample increases by 10% with respect to uncalcined sample

Thermal and structural characterization of synthetic and natural nanocrystalline hydroxyapatite

Energy Technology Data Exchange (ETDEWEB)

Sofronia, Ancuta M. [Ilie Murgulescu Institute of Physical Chemistry of the Romanian Academy, 060021 Bucharest (Romania); Baies, Radu [National Research Institute for Electrochemistry and Condensed Matter, 300224 Timisoara (Romania); Anghel, Elena M. [Ilie Murgulescu Institute of Physical Chemistry of the Romanian Academy, 060021 Bucharest (Romania); Marinescu, Cornelia A., E-mail: alcorina@chimfiz.icf.ro [Ilie Murgulescu Institute of Physical Chemistry of the Romanian Academy, 060021 Bucharest (Romania); Tanasescu, Speranta [Ilie Murgulescu Institute of Physical Chemistry of the Romanian Academy, 060021 Bucharest (Romania)

2014-10-01

The aim of this work was to study the thermal stability on heating and to obtain the processing parameters of synthetic and bone-derived hydroxyapatite over temperatures between room temperature and 1400 °C by thermal analysis (thermogravimetry (TG)/differential scanning calorimetry (DSC) and thermo-mechanical analysis—TMA). Structural and surface modifications related to samples origin and calcination temperature were investigated by Fourier transformed infrared (FTIR) and Raman spectroscopy, X-ray diffraction (XRD) and BET method. FTIR spectra indicated that the organic constituents and carbonate are no longer present in the natural sample calcined at 800 °C. Raman spectra highlighted the decomposition products of the hydroxyapatite. The calcination treatment modifies the processes kinetics of the synthetic samples, being able to isolate lattice water desorption processes of decarbonization and the dehydroxylation processes. Shrinkage of calcined synthetic sample increases by 10% compared to uncalcined synthetic powder. From the TMA correlated with TG analysis and heat capacity data it can be concluded that sintering temperature of the synthetic samples should be chosen in the temperature range of the onset of dehydroxylation and the temperature at which oxyapatite decomposition begins. - Highlights: • Specific surface area of HA powder was reduced from 19.2 to 9.5 m{sup 2}/g by calcination. • Raman spectra indicate the presence of B-type CO{sub 3} group in HA synthetic samples. • The onset temperature of HA densification and dehydroxylation processes correspond. • Calcination of HA influences reactions kinetics with consequences on densification. • Shrinkage of calcined HA sample increases by 10% with respect to uncalcined sample.

Research on cloud background infrared radiation simulation based on fractal and statistical data

Science.gov (United States)

Liu, Xingrun; Xu, Qingshan; Li, Xia; Wu, Kaifeng; Dong, Yanbing

2018-02-01

Cloud is an important natural phenomenon, and its radiation causes serious interference to infrared detector. Based on fractal and statistical data, a method is proposed to realize cloud background simulation, and cloud infrared radiation data field is assigned using satellite radiation data of cloud. A cloud infrared radiation simulation model is established using matlab, and it can generate cloud background infrared images for different cloud types (low cloud, middle cloud, and high cloud) in different months, bands and sensor zenith angles.

Impact strength of sintered astaloy CrM powders

International Nuclear Information System (INIS)

Kazior, J.; Ploszczak, J.; Nykiel, M.; Pieczonka, T.

2003-01-01

In this paper results of a series of impact tests on sintered Astaloy CrM powders alloys modified by boron are presented and discussed. Boron in different forms, i.e. as elemental boron powder, boron carbide B 4 C powder or mixture of boron and carbon elemental powders, was used in different weight percentage to activate sintering of Astaloy CrM powder and to increase hardenability, with aim of increasing impact strength in view of structural applications. (author)

Shock compaction of molybdenum powder

Science.gov (United States)

Ahrens, T. J.; Kostka, D.; Vreeland, T., Jr.; Schwarz, R. B.; Kasiraj, P.

1983-01-01

Shock recovery experiments which were carried out in the 9 to 12 GPa range on 1.4 distension Mo and appear adequate to compact to full density ( 45 (SIGMA)m) powders were examined. The stress levels, however, are below those calculated to be from 100 to approx. 22 GPa which a frictional heating model predicts are required to consolidate approx. 10 to 50 (SIGMA)m particles. The model predicts that powders that have a distension of m=1.6 shock pressures of 14 to 72 GPa are required to consolidate Mo powders in the 50 to 10 (SIGMA)m range.

The effect of YBa2Cu3O7-x powder characteristics on thick coatings prepared by atmospheric plasma spraying

International Nuclear Information System (INIS)

Georgiopoulos, E.; Tsetsekou, A.

2000-01-01

The development of superconducting YBa 2 Cu 3 O 7-x plasma sprayed coatings on metal substrates can be very useful for applications such as targets for thin-film deposition techniques (sputtering, laser ablation, ion assisted deposition) or magnetic shielding, due to the brittle nature of bulk superconductors. The plasma spraying technique is very flexible and can be used for manufacturing components with a large variety of geometries. This technique requires the use of powders with good rheological characteristics. In this study, YBa 2 Cu 3 O 7-x powders were produced by using the conventional solid-state reaction route and also by spray drying a solution of nitrate precursors. Both powders, as well as mixtures of them, were plasma sprayed to develop coatings on stainless-steel substrates, with the aim of studying the effect of the feedstock powder characteristics on the coating properties. It was found that by optimizing the plasma spraying conditions, good quality coatings could be obtained. However, the powder morphology and homogeneity significantly affect the coating quality. More homogeneous powders lead to better results, the spray-dried powder being the best because of its enhanced rheological properties and good morphology. (author)

Metal powder production by gas atomization

Science.gov (United States)

Ting, E. Y.; Grant, N. J.

1986-01-01

The confined liquid, gas-atomization process was investigated. Results from a two-dimensional water model showed the importance of atomization pressure, as well as delivery tube and atomizer design. The atomization process at the tip of the delivery tube was photographed. Results from the atomization of a modified 7075 aluminum alloy yielded up to 60 wt pct. powders that were finer than 45 microns in diameter. Two different atomizer designs were evaluated. The amount of fine powders produced was correlated to a calculated gas-power term. An optimal gas-power value existed for maximized fine powder production. Atomization at gas-power greater than or less than this optimal value produced coarser powders.

Near-infrared incoherent broadband cavity enhanced absorption spectroscopy (NIR-IBBCEAS) for detection and quantification of natural gas components.

Science.gov (United States)

Prakash, Neeraj; Ramachandran, Arun; Varma, Ravi; Chen, Jun; Mazzoleni, Claudio; Du, Ke

2018-06-28

The principle of near-infrared incoherent broadband cavity enhanced absorption spectroscopy was employed to develop a novel instrument for detecting natural gas leaks as well as for testing the quality of natural gas mixtures. The instrument utilizes the absorption features of methane, butane, ethane, and propane in the wavelength region of 1100 nm to 1250 nm. The absorption cross-section spectrum in this region for methane was adopted from the HITRAN database, and those for the other three gases were measured in the laboratory. A singular-value decomposition (SVD) based analysis scheme was employed for quantifying methane, butane, ethane, and propane by performing a linear least-square fit. The developed instrument achieved a detection limit of 460 ppm, 141 ppm, 175 ppm and 173 ppm for methane, butane, ethane, and propane, respectively, with a measurement time of 1 second and a cavity length of 0.59 m. These detection limits are less than 1% of the Lower Explosive Limit (LEL) for each gas. The sensitivity can be further enhanced by changing the experimental parameters (such as cavity length, lamp power etc.) and using longer averaging intervals. The detection system is a low-cost and portable instrument suitable for performing field monitorings. The results obtained on the gas mixture emphasize the instrument's potential for deployment at industrial facilities dealing with natural gas, where potential leaks pose a threat to public safety.

Nanoscale charcoal powder induced saturable absorption and mode-locking of a low-gain erbium-doped fiber-ring laser

International Nuclear Information System (INIS)

Lin, Yung-Hsiang; Chi, Yu-Chieh; Lin, Gong-Ru

2013-01-01

Triturated charcoal nano-powder directly brushed on a fiber connector end-face is used for the first time as a fast saturable absorber for a passively mode-locked erbium-doped fiber-ring laser (EDFL). These dispersant-free charcoal nano-powders with a small amount of crystalline graphene phase and highly disordered carbon structure exhibit a broadened x-ray diffraction peak and their Raman spectrum shows the existence of a carbon related D-band at 1350 cm −1 and the disappearance of the 2D-band peak at 2700 cm −1 . The charcoal nano-powder exhibits a featureless linear absorbance in the infrared region with its linear transmittance of 0.66 nonlinearly saturated at 0.73 to give a ΔT/T of 10%. Picosecond mode-locking at a transform-limited condition of a low-gain EDFL is obtained by using the charcoal nano-powder. By using a commercial EDFA with a linear gain of only 17 dB at the saturated output power of 17.5 dB m required to initiate the saturable absorption of the charcoal nano-powder, the EDFL provides a pulsewidth narrowing from 3.3 to 1.36 ps associated with its spectral linewidth broadening from 0.8 to 1.83 nm on increasing the feedback ratio from 30 to 90%. This investigation indicates that all the carbon-based materials containing a crystalline graphene phase can be employed to passively mode-lock the EDFL, however, the disordered carbon structure inevitably induces a small modulation depth and a large mode-locking threshold, thus limiting the pulsewidth shortening. Nevertheless, the nanoscale charcoal passively mode-locked EDFL still shows the potential to generate picosecond pulses under a relatively low cavity gain. An appropriate cavity design can be used to compensate this defect-induced pulsewidth limitation and obtain a short pulsewidth. (letter)

Metallography of powder metallurgy materials

International Nuclear Information System (INIS)

Lawley, Alan; Murphy, Thomas F.

2003-01-01

The primary distinction between the microstructure of an ingot metallurgy/wrought material and one fabricated by the powder metallurgy route of pressing followed by sintering is the presence of porosity in the latter. In its various morphologies, porosity affects the mechanical, physical, chemical, electrical and thermal properties of the material. Thus, it is important to be able to characterize quantitatively the microstructure of powder metallurgy parts and components. Metallographic procedures necessary for the reliable characterization of microstructures in powder metallurgy materials are reviewed, with emphasis on the intrinsic challenges presented by the presence of porosity. To illustrate the utility of these techniques, five case studies are presented involving powder metallurgy materials. These case studies demonstrate problem solving via metallography in diverse situations: failure of a tungsten carbide-coated precipitation hardening stainless steel, failure of a steel pump gear, quantification of the degree of sinter (DOS), simulation of performance of a porous filter using automated image analysis, and analysis of failure in a sinter brazed part assembly

WATER HYACINTH: A POSSIBLE ALTERNATIVE RATE RETARDING NATURAL POLYMER USED IN SUSTAINED RELEASE TABLET DESIGN

Directory of Open Access Journals (Sweden)

Sabera eKhatun

2014-06-01

Full Text Available In recent years natural polymers have been widely used, because of their effectiveness and availability over synthetic polymers. In this present investigation matrix tablets of Metformin hydrochloride were formulated using Water hyacinth powder and its rate retardant activity was studied. Tablets were prepared using wet granulation method with 8% starch as granulating agent and 5%, 10%, 15%, 20%, 25% and 30% of Water hyacinth powder to the drug. In preformulation study, angle of repose, Carr’s Index and Hausner ratio were calculated. Fourier Transform Infrared Spectroscopy (FTIR, Differential Scanning Calorimetry (DSC and Scanning Electron Microscopy (SEM studies were performed and no interactions were found between drug and excipients. Weight variation, friability, hardness, thickness, diameter, and in vitro release study were performed with the prepared matrix tablets. Dissolution studies were conducted using USP type II apparatus at a speed of 100 rpm at 37oC ± 0.5 temperature, for 8 hours. All the formulations comply with both BP and USP requirements, but among all the formulations F-1 (5% of Water hyacinth was the best fitted formula. The drug release patterns were explained in different kinetic models such as Zero order, First order, Higuchi, Hixson Crowell and Korsmeyer-Peppas equations. The current investigation implies that Water hyacinth has the potential to be used as a rate-retarding agent in sustained release drug formulations.

Water hyacinth: a possible alternative rate retarding natural polymer used in sustained release tablet design.

Science.gov (United States)

Khatun, Sabera; Sutradhar, Kumar B

2014-01-01

In recent years natural polymers have been widely used because of their effectiveness and availability over synthetic polymers. In this present investigation matrix tablets of Metformin hydrochloride were formulated using Water hyacinth powder and its rate retardant activity was studied. Tablets were prepared using wet granulation method with 8% starch as granulating agent and 5, 10, 15, 20, 25 and 30% of Water hyacinth powder to the drug. In preformulation study, angle of repose, Carr's Index and Hausner ratio were calculated. Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), and Scanning Electron Microscopy (SEM) studies were performed and no interactions were found between drug and excipients. Weight variation, friability, hardness, thickness, diameter, and in vitro release study were performed with the prepared matrix tablets. Dissolution studies were conducted using USP type II apparatus at a speed of 100 rpm at 37°C ± 0.5 temperature for 8 h. Though all the formulations comply with both BP and USP requirements, formulation F-1 (5% of Water hyacinth) was the best fitted formula. The drug release patterns were explained in different kinetic models such as Zero order, First order, Higuchi, Hixson Crowell, and Korsmeyer-Peppas equations. The current investigation implies that Water hyacinth has the potential to be used as a rate-retarding agent in sustained release drug formulations.

Effect of temperature on sequestration of Cu (II) from aqueous solution onto turmeric powder

International Nuclear Information System (INIS)

Qayoom, A.

2010-01-01

In this work effect of temperature on adsorption of Cu(II) onto turmeric powder was investigated in order to understand sequestrating behavior of turmeric powder. Langmuir, Freundlich and D-R equilibrium models were employed and changes in equilibrium parameters with changing temperature have been discussed. Various thermodynamic parameters such as delta H, delta G and delta S have been calculated. It was found that with increase in temperature maximum adsorption capacities of Cu(II) increase which showed that the adsorption of Cu(II) onto turmeric powder is endothermic. delta H and Ea values also confirmed the same trend. Entropy values showed increased in randomness with increasing temperature. Gibbs free energies were non spontaneous at all the temperatures studied. E values were in the range of 2.89-3.53 KJmol /sup -1/, which indicated that adsorption is essentially of physical nature. The value of S is much less than 1 indicating favourable sticking of adsorbate to adsorbent with physiosorption mechanism predominant. (author)

Spheroidization of molybdenum powder by radio frequency thermal plasma

Science.gov (United States)

Liu, Xiao-ping; Wang, Kuai-she; Hu, Ping; Chen, Qiang; Volinsky, Alex A.

2015-11-01

To control the morphology and particle size of dense spherical molybdenum powder prepared by radio frequency (RF) plasma from irregular molybdenum powder as a precursor, plasma process parameters were optimized in this paper. The effects of the carrier gas flow rate and molybdenum powder feeding rate on the shape and size of the final products were studied. The molybdenum powder morphology was examined using high-resolution scanning electron microscopy. The powder phases were analyzed by X-ray diffraction. The tap density and apparent density of the molybdenum powder were investigated using a Hall flow meter and a Scott volumeter. The optimal process parameters for the spherical molybdenum powder preparation are 50 g/min powder feeding rate and 0.6 m3/h carrier gas rate. In addition, pure spherical molybdenum powder can be obtained from irregular powder, and the tap density is enhanced after plasma processing. The average size is reduced from 72 to 62 µm, and the tap density is increased from 2.7 to 6.2 g/cm3. Therefore, RF plasma is a promising method for the preparation of high-density and high-purity spherical powders.

The effect of pulping concentration treatment on the properties of microcrystalline cellulose powder obtained from waste paper.

Science.gov (United States)

Okwonna, Okumneme O

2013-10-15

Microcrystalline cellulose (MCC) powder was isolated from three grades of waste paper: book, Groundwood/Newsprint and paperboard, through the processes of pulping and hydrolysis. Pulping treatment on these grades of waste paper was done using varying concentrations of caustic soda. Effects of the concentration of the pulping medium on the thermal and kinetic properties were investigated. Also determined were the effects of this on the physico-chemical properties. The chemical structure was characterized using an infrared spectroscopy (FTIR). Results showed these properties to be affected by the concentration of the pulping medium. Copyright © 2013 Elsevier Ltd. All rights reserved.

Far-infrared observations of Sagittarius B2 - reconsideration of source structure

International Nuclear Information System (INIS)

Thronson, H.A. Jr.; Harper, D.A.; Yerkes Observatory, Williams Bay, WI)

1986-01-01

New moderate-angular-resolution far-infrared observations of the Sagittarius B2 star-forming region are presented, discussed, and compared with recent radio molecular and continuum observations of this source. In contrast to previous analyses, its far-infrared spectrum is interpreted as the result of a massive frigid cloud overlying a more-or-less normal infrared source, a natural explanation for the object's previously-noted peculiarities. The characteristics derived for the obscuring cloud are similar to those found for the W51 MAIN object. Both sources have high sub-millimeter surface brightness, a high ratio of sub-millimeter to far-infrared flux, and numerous regions of molecular maser emission. 28 references

In-house characterization of protein powder

DEFF Research Database (Denmark)

Hartmann, Christian Grundahl; Nielsen, Ole Faurskov; Ståhl, Kenny

2010-01-01

X-ray powder diffraction patterns of lysozyme and insulin were recorded on a standard in-house powder diffractometer. The experimental powder diffraction patterns were compared with patterns calculated from Protein Data Bank coordinate data. Good agreement was obtained by including straightforward...... to include calculated H-atom positions did not improve the overall fit and was abandoned. The method devised was shown to be a quick and convenient tool for distinguishing precipitates and polymorphs of proteins....

Powder handling for automated fuel processing

International Nuclear Information System (INIS)

Frederickson, J.R.; Eschenbaum, R.C.; Goldmann, L.H.

1989-01-01

Installation of the Secure Automated Fabrication (SAF) line has been completed. It is located in the Fuel Cycle Plant (FCP) at the Department of Energy's (DOE) Hanford site near Richland, Washington. The SAF line was designed to fabricate advanced reactor fuel pellets and assemble fuel pins by automated, remote operation. This paper describes powder handling equipment and techniques utilized for automated powder processing and powder conditioning systems in this line. 9 figs

Effects of UV-B radiation levels on concentrations of phytosterol, ergothioneine, and polyphenolic compounds in mushroom powder used as dietary supplements

Science.gov (United States)

Compositional changes of powder dietary supplement made from mushrooms previously exposed to different levels of UV-B irradiation were evaluated for the bioactive naturally occurring mushroom anti-oxidant, ergothioneine, other natural polyphenolic anti-oxidants: e.g. flavonoids, lignans, and others,...

Development of granular powder manufacturing technology by spray pyrolysis

International Nuclear Information System (INIS)

Katoh, Yoshiyuki; Kawase, Keiichi; Takahashi, Yoshiharu; Todokoro, Akio

1996-01-01

For shortening of mixed-oxide (MOX) fuel manufacturing process and improvement in treatment of MOX-powder, we have been developing the granular powder production technology. Since the granular powders have excellent fluidity owing to the spherical shape, there is the possibility of modifying scattering and adcering of the powder in the process equipment. In this paper, spray pyrolysis process in adopted as the process of manufacturing the granular powders and the basic feasibility study has been carried out. The experimental results show that the manufactured granular powders have excellent fluidity and the diameter of the powders is controllable. Furthermore, high density pellets are formed by sintering the powders. Thus, it is clarified that this process is promising for the actual MOX fuel fabrication. (author)

Vibration-Assisted Handling of Dry Fine Powders

Directory of Open Access Journals (Sweden)

Paul Dunst

2018-04-01

Full Text Available Since fine powders tend strongly to adhesion and agglomeration, their processing with conventional methods is difficult or impossible. Typically, in order to enable the handling of fine powders, chemicals are added to increase the flowability and reduce adhesion. This contribution shows that instead of additives also vibrations can be used to increase the flowability, to reduce adhesion and cohesion, and thus to enable or improve processes such as precision dosing, mixing, and transport of very fine powders. The methods for manipulating powder properties are described in detail and prototypes for experimental studies are presented. It is shown that the handling of fine powders can be improved by using low-frequency, high-frequency or a combination of low- and high-frequency vibration.

Design, characterization, and aerosolization of organic solution advanced spray-dried moxifloxacin and ofloxacin dipalmitoylphosphatidylcholine (DPPC) microparticulate/nanoparticulate powders for pulmonary inhalation aerosol delivery

Science.gov (United States)

Duan, Jinghua; Vogt, Frederick G; Li, Xiaojian; Hayes, Don; Mansour, Heidi M

2013-01-01

The aim of this study was to design and develop respirable antibiotics moxifloxacin (MOXI) hydrochloride and ofloxacin (OFLX) microparticles and nanoparticles, and multifunctional antibiotics particles with or without lung surfactant 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) for targeted dry powder inhalation delivery as a pulmonary nanomedicine. Particles were rationally designed and produced by advanced spray-drying particle engineering from an organic solution in closed mode (no water) from dilute solution. Scanning electron microscopy indicated that these particles had both optimal particle morphology and surface morphology, and the particle size distributions were suitable for pulmonary delivery. Comprehensive and systematic physicochemical characterization and in vitro aerosol dispersion performance revealed significant differences between these two fluoroquinolone antibiotics following spray drying as drug aerosols and as cospray-dried antibiotic drug: DPPC aerosols. Fourier transform infrared spectroscopy and confocal Raman microspectroscopy were employed to probe composition and interactions in the solid state. Spray-dried MOXI was rendered noncrystalline (amorphous) following organic solution advanced spray drying. This was in contrast to spray-dried OFLX, which retained partial crystallinity, as did OFLX:DPPC powders at certain compositions. Aerosol dispersion performance was conducted using inertial impaction with a dry powder inhaler device approved for human use. The present study demonstrates that the use of DPPC offers improved aerosol delivery of MOXI as cospray-dried microparticulate/nanoparticulate powders, whereas residual partial crystallinity influenced aerosol dispersion of OFLX and most of the compositions of OFLX:DPPC inhalation powders. PMID:24092972

Face recognition in the thermal infrared domain

Science.gov (United States)

Kowalski, M.; Grudzień, A.; Palka, N.; Szustakowski, M.

2017-10-01

Biometrics refers to unique human characteristics. Each unique characteristic may be used to label and describe individuals and for automatic recognition of a person based on physiological or behavioural properties. One of the most natural and the most popular biometric trait is a face. The most common research methods on face recognition are based on visible light. State-of-the-art face recognition systems operating in the visible light spectrum achieve very high level of recognition accuracy under controlled environmental conditions. Thermal infrared imagery seems to be a promising alternative or complement to visible range imaging due to its relatively high resistance to illumination changes. A thermal infrared image of the human face presents its unique heat-signature and can be used for recognition. The characteristics of thermal images maintain advantages over visible light images, and can be used to improve algorithms of human face recognition in several aspects. Mid-wavelength or far-wavelength infrared also referred to as thermal infrared seems to be promising alternatives. We present the study on 1:1 recognition in thermal infrared domain. The two approaches we are considering are stand-off face verification of non-moving person as well as stop-less face verification on-the-move. The paper presents methodology of our studies and challenges for face recognition systems in the thermal infrared domain.

Evaluation of ring shear testing as a characterization method for powder flow in small-scale powder processing equipment

DEFF Research Database (Denmark)

Søgaard, Søren Vinter; Pedersen, Troels; Allesø, Morten

2014-01-01

Powder flow in small-scale equipment is challenging to predict. To meet this need, the impact of consolidation during powder flow characterization, the level of consolidation existing during discharge of powders from a tablet press hopper and the uncertainty of shear and wall friction measurements...... normal stress were approximately 200Pa and 114Pa, respectively, in the critical transition from the converging to the lower vertical section of the hopper. The lower limit of consolidation for the shear and wall friction test was approximately 500Pa and 200Pa, respectively. At this consolidation level......, the wall and shear stress resolution influences the precision of the measured powder flow properties. This study highlights the need for an improved experimental setup which would be capable of measuring the flow properties of powders under very small consolidation stresses with a high shear stress...

2016 - Color & Infrared - Rutland and Windsor (0.15m)

Data.gov (United States)

Vermont Center for Geographic Information — (Link to Metadata) This metadata record describes the acquisition and production of natural color and color infrared digital ground orthoimagery covering a portion...

2016 - Color & Infrared - Rutland and Windsor (0.3m)

Data.gov (United States)

Vermont Center for Geographic Information — (Link to Metadata) This metadata record describes the acquisition and production of natural color and color infrared digital ground orthoimagery covering a portion...

An Efficient Approach to Address Issues of Graphene Nanoplatelets (GNPs Incorporation in Aluminium Powders and Their Compaction Behaviour

Directory of Open Access Journals (Sweden)

Zeeshan Baig

2018-01-01

Full Text Available The exceptional potential of the graphene has not been yet fully translated into the Al matrix to achieve high-performance Al nanocomposite. This is due to some critical issues faced by graphene during its processing such as the dispersion uniformity, structure damage, compatibility/wettability, and low graphene embedding content in Al matrix. In the present work, a new integrative method was adopted and named as “solvent dispersion and ball milling” (SDBM to address the issues above efficiently in a single approach. This strategy involves effective graphene nanoplatelets (GNPs solvent dispersion via surfactant decoration and solution ball milling employed to polyvinyl alcohol (PVA coated Al with various GNPs content (0.5, 1 and 1.5 wt. %. Flaky Al powder morphology attained by optimizing ball milling parameters and used for further processing with GNPs. Detailed powders characterizations were conducted to investigate morphology, graphene dispersion, group functionalities by FTIR (Fourier transform infrared spectroscopy spectroscopy and crystallinity by powder XRD (X-ray diffractionanalysis. Compaction behaviour and spring back effect of the GNPs/Al powders was also investigated at different compaction pressure (300 to 600 Mpa and varying GNPs fractions. In response, green and sintered relative density (% along with effect on the hardness of the nanocomposites samples were examined. Conclusively, in comparison with the unreinforced Al, GNP/Al nanocomposite with 1.5 wt. % GNPs exhibited the highest hardness gives 62% maximum increase than pure Al validates the effectiveness of the approach produces high fraction uniformly dispersed GNPs in Al matrix.

Fabrication of nuclear fuel by powder injection moulding: Study of the binders systems and the de-binding of feedstock containing actinide powder

International Nuclear Information System (INIS)

Bricout, J.

2012-01-01

Powder Injection Moulding (PIM) is identified as an innovative process for the nuclear fuel fabrication. Technological breakthrough compared to the current process of powder metallurgy, the impact of actinide powder's specificities on the different steps of PIM is performed. Alumina powders simulating actinide powder have been implemented with a reference binders system. Thermal and rheological studies show the injectability and the de-binding of feedstocks with adequate solid loading (≥50 %vol), thanks to the de-agglomeration during the mixing step, which allow to obtain net shape fuel pellet. Specific surface area of powders, acting as a key role in behaviour's feedstocks, has been integrated in analysis models of viscosity prediction according to the shear rate. Also conducted studies on uranium oxide powder show that the selected binders systems, which have a compatible rheological behaviour with PIM process, impact the de-agglomeration of powder and final microstructure of the fuel pellet, consistent with the results obtained on alumina powders. Independent behaviour of binders and uranium oxide powder, showing no adverse chemical reaction against the PIM process, show a residual mass of carbon of about 150 ppm after sintering. Binders system using polystyrene, resistant to radiolysis phenomena and loadable more than 50 %(vol) of actinide powder, shows the promising potential of PIM process for the fuel fabrication. (author) [fr

Spray drying of beryllium oxide powder

International Nuclear Information System (INIS)

Sepulveda, J.L.; Kahler, D.A.

1991-01-01

Forming of beryllia ceramics through dry pressing requires the agglomeration of the powder through spray drying. To produce high quality fired ceramics it is necessary to disperse/grind the primary powder prior to binder addition. Size reduction of the powder is accomplished using an aqueous system in Vibro-Energy mills (VEM) charged with beryllia media to minimize contamination. Two VEM mills of different size were used to characterize the grinding operation. Details of the grinding kinetics are described within the context of the Macroscopic Population Balance Model approach. Spray drying of the ceramic slurry was accomplished with both a centrifugal atomizer and a two fluid nozzle atomizer. Two different spray dryers were used. Important operating parameters affecting the size distribution of the spray dried powder are discussed

Attenuated Total Reflection Mid-Infrared (ATR-MIR) Spectroscopy and Chemometrics for the Identification and Classification of Commercial Tannins.

Science.gov (United States)

Ricci, Arianna; Parpinello, Giuseppina P; Olejar, Kenneth J; Kilmartin, Paul A; Versari, Andrea

2015-11-01

Attenuated total reflection Fourier transform infrared (FT-IR) spectroscopy was used to characterize 40 commercial tannins, including condensed and hydrolyzable chemical classes, provided as powder extracts from suppliers. Spectral data were processed to detect typical molecular vibrations of tannins bearing different chemical groups and of varying botanical origin (univariate qualitative analysis). The mid-infrared region between 4000 and 520 cm(-1) was analyzed, with a particular emphasis on the vibrational modes in the fingerprint region (1800-520 cm(-1)), which provide detailed information about skeletal structures and specific substituents. The region 1800-1500 cm(-1) contained signals due to hydrolyzable structures, while bands due to condensed tannins appeared at 1300-900 cm(-1) and exhibited specific hydroxylation patterns useful to elucidate the structure of the flavonoid monomeric units. The spectra were investigated further using principal component analysis for discriminative purposes, to enhance the ability of infrared spectroscopy in the classification and quality control of commercial dried extracts and to enhance their industrial exploitation.

Method of producing radioactive carbon powder

International Nuclear Information System (INIS)

Imamura, Y.

1980-01-01

Carbon powder, placed in a hermetically closed apparatus under vacuum together with radium ore, adsorbs radon gas emanating from the radium ore thus producing a radioactive carbonaceous material, the radioactivity of which is due to the presence of adsorbed radon. The radioactive carbon powder thus obtained has excellent therapeutical efficacy and is suitable for a variety of applications because of the mild radioactivity of radon. Radium ore permits substantially limitlessly repeated production of the radioactive carbon powder

Preparation techniques for ceramic waste form powder

International Nuclear Information System (INIS)

Hash, M.C.; Pereira, C.; Lewis, M.A.

1997-01-01

The electrometallurgical treatment of spent nuclear fuels result in a chloride waste salt requiring geologic disposal. Argonne National Laboratory (ANL) is developing ceramic waste forms which can incorporate this waste. Currently, zeolite- or sodalite-glass composites are produced by hot isostatic pressing (HIP) techniques. Powder preparations include dehydration of the raw zeolite powders, hot blending of these zeolite powders and secondary additives. Various approaches are being pursued to achieve adequate mixing, and the resulting powders have been HIPed and characterized for leach resistance, phase equilibria, and physical integrity

Preparation of ultra-fine powders from polysaccharide-coated solid lipid nanoparticles and nanostructured lipid carriers by innovative nano spray drying technology.

Science.gov (United States)

Wang, Taoran; Hu, Qiaobin; Zhou, Mingyong; Xue, Jingyi; Luo, Yangchao

2016-09-10

In this study, five polysaccharides were applied as natural polymeric coating materials to prepare solid lipid nanoparticles (SLN) and nanostructure lipid carriers (NLC), and then the obtained lipid colloidal particles were transformed to solid powders by the innovative nano spray drying technology. The feasibility and suitability of this new technology to generate ultra-fine lipid powder particles were evaluated and the formulation was optimized. The spray dried SLN powder exhibited the aggregated and irregular shape and dimension, but small, uniform, well-separated spherical powder particles of was obtained from NLC. The optimal formulation of NLC was prepared by a 20-30% oleic acid content with carrageenan or pectin as coating material. Therefore, nano spray drying technology has a potential application to produce uniform, spherical, and sub-microscale lipid powder particles when the formulation of lipid delivery system is appropriately designed. Copyright © 2016 Elsevier B.V. All rights reserved.

Synthesis of a TiBw/Ti6Al4V composite by powder compact extrusion using a blended powder mixture

Energy Technology Data Exchange (ETDEWEB)

Lu, Huiyang, E-mail: hl209@waikato.ac.nz [Waikato Center for Advanced Materials, School of Engineering, University of Waikato, Hamilton (New Zealand); Zhang, Deliang, E-mail: zhangdeliang@sjtu.edu.cn [State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai (China); Gabbitas, Brian, E-mail: briang@waikato.ac.nz [Waikato Center for Advanced Materials, School of Engineering, University of Waikato, Hamilton (New Zealand); Yang, Fei, E-mail: fyang@waikato.ac.nz [Waikato Center for Advanced Materials, School of Engineering, University of Waikato, Hamilton (New Zealand); Matthews, Steven, E-mail: S.Matthews@massey.ac.nz [School of Engineering and Advanced Technology, Massey University, Auckland (New Zealand)

2014-09-01

Highlights: • TiB/Ti6Al4V composites were prepared from extruded BE powders. • Different starting powders affected the morphologies of TiB whiskers formed in-situ. • A TiB/Ti6Al4V composite with TiB whiskers had good strength and ductility. • The strength and ductility achieved were superior to those obtained by other methods. - Abstract: A Ti–6 wt%Al–4 wt%V alloy (Ti6Al4V) matrix composite, reinforced by in situ synthesized TiB whiskers (TiBw) has been successfully fabricated by powder compact extrusion using a blended powder mixture. The microstructural characterization of the various extruded samples showed that the different starting powders, pre-alloyed powder plus boron powder or titanium plus Al–40V master alloy powder plus boron powder, had a significant effect on the morphology of the in situ synthesized TiB whiskers. It is also evident that the TiB whiskers affect the microstructural evolution of the Ti6Al4V matrix. The tensile test results indicated that the composite with a dispersion of fine TiB whiskers with high aspect ratios exhibited a high ultimate tensile stress (UTS) and yield stress (YS) of 1436 MPa and 1361 MPa, respectively, a reasonably good tensile ductility reflected by an elongation to fracture of 5.6% was also achieved. This is a significant improvement compared with as-extruded monolithic Ti6Al4V alloy produced in this study.

Synthesis of a TiBw/Ti6Al4V composite by powder compact extrusion using a blended powder mixture

International Nuclear Information System (INIS)

Lu, Huiyang; Zhang, Deliang; Gabbitas, Brian; Yang, Fei; Matthews, Steven

2014-01-01

Highlights: • TiB/Ti6Al4V composites were prepared from extruded BE powders. • Different starting powders affected the morphologies of TiB whiskers formed in-situ. • A TiB/Ti6Al4V composite with TiB whiskers had good strength and ductility. • The strength and ductility achieved were superior to those obtained by other methods. - Abstract: A Ti–6 wt%Al–4 wt%V alloy (Ti6Al4V) matrix composite, reinforced by in situ synthesized TiB whiskers (TiBw) has been successfully fabricated by powder compact extrusion using a blended powder mixture. The microstructural characterization of the various extruded samples showed that the different starting powders, pre-alloyed powder plus boron powder or titanium plus Al–40V master alloy powder plus boron powder, had a significant effect on the morphology of the in situ synthesized TiB whiskers. It is also evident that the TiB whiskers affect the microstructural evolution of the Ti6Al4V matrix. The tensile test results indicated that the composite with a dispersion of fine TiB whiskers with high aspect ratios exhibited a high ultimate tensile stress (UTS) and yield stress (YS) of 1436 MPa and 1361 MPa, respectively, a reasonably good tensile ductility reflected by an elongation to fracture of 5.6% was also achieved. This is a significant improvement compared with as-extruded monolithic Ti6Al4V alloy produced in this study

MATHEMATICAL MODELING OF INFRARED MILK PASTEURIZATION

Directory of Open Access Journals (Sweden)

S. T. Antipov

2013-01-01

Full Text Available Based on the model representation of the process of pasteurization of milk infrared patterns of change in temperature of the product in the heating zone with the heat flows of different nature were obtained. The changes in the basic performance of the quartz oscillator during operation were also obtained.

Influence of ambient moisture on the compaction behavior of microcrystalline cellulose powder undergoing uni-axial compression and roller-compaction: a comparative study using near-infrared spectroscopy.

Science.gov (United States)

Gupta, Abhay; Peck, Garnet E; Miller, Ronald W; Morris, Kenneth R

2005-10-01

This study evaluates the effect of variation in the ambient moisture on the compaction behavior of microcrystalline cellulose (MCC) powder. The study was conducted by comparing the physico-mechanical properties of, and the near infrared (NIR) spectra collected on, compacts prepared by roller compaction with those collected on simulated ribbons, that is, compacts prepared under uni-axial compression. Relative density, moisture content, tensile strength (TS), and Young modulus were used as key sample attributes for comparison. Samples prepared at constant roller compactor settings and feed mass showed constant density and a decrease in TS with increasing moisture content. Compacts prepared under uni-axial compression at constant pressure and compact mass showed the opposite effect, that is, density increased while TS remained almost constant with increasing moisture content. This suggests difference in the influence of moisture on the material under roller compaction, in which the roll gap (i.e., thickness and therefore density) remains almost constant, vs. under uni-axial compression, in which the thickness is free to change in response to the applied pressure. Key sample attributes were also related to the NIR spectra using multivariate data analysis by the partial least squares projection to latent structures (PLS). Good agreement was observed between the measured and the NIR-PLS predicted values for all key attributes for both, the roller compacted samples as well as the simulated ribbons. Copyright (c) 2005 Wiley-Liss, Inc. and the American Pharmacists Association

(YSZ) powders

Indian Academy of Sciences (India)

Unknown

109–114. © Indian Academy of Sciences. 109 ... Materials Science Division, Bhabha Atomic Research Centre, Mumbai 400 085, India .... pensions of 900°C calcined YSZ powders. .... The sintered density data of the compacts (sintered at.

Water Outgassing from PBX-9502 powder by isoconversional thermal analysis

International Nuclear Information System (INIS)

Dinh, L.N.; Glascoe, E.L.; Small, W.

2009-01-01

Temperature programmed desorption/decomposition (TPD) were performed on PBX-9502 after 3 hours of vacuum pump. TPD data were analyzed by the technique of isoconversional analysis to obtain outgassing kinetics and moisture content of PBX-9502 powder as well as to construct water outgassing models for PBX-9502 powder as a function of time and temperature. Following 3 hours of vacuum pump, dry storage of PBX-9502 at 300K, quickly gives rise to 180-330 ppm moisture in the first few years. Thereafter, the moisture outgassing continues at a much slower rate, totaling only to ∼ 210-380 ppm after 100 years of storage. In an effort to understand the nature of the moisture outgassing in PBX-9502, we have measured moisture content and outgassing kinetics in PBX-9502 by the experimental technique of TPD and the isoconversional thermal analysis. The results of these measurements were then used to construct moisture outgassing models for PBX-9502 in a dry environment (following 3 hours of vacuum pump)

Internal Friction Angle of Metal Powders

Directory of Open Access Journals (Sweden)

Jiri Zegzulka

2018-04-01

Full Text Available Metal powders are components with multidisciplinary usage as their application is very broad. Their consistent characterization across all disciplines is important for ensuring repeatable and trouble-free processes. Ten metal powders were tested in the study. In all cases, the particle size distribution and morphology (scanning electron microscope—SEM photos were determined. The aim of this work was to inspect the flow behavior of metal powders through another measured characteristic, namely the angle of internal friction. The measured values of the effective internal friction angle in the range 28.6–32.9°, together with the spherical particle shape and the particle size distribution, revealed the likely dominant mode of the metal particle transfer mechanism for stainless steel 316L, zinc and aluminum powder. This third piston flow mechanism is described and illustrated in detail. The angle of internal friction is mentioned as another suitable parameter for the characterization of metal powders, not only for the relative simplicity of the determination but also for gaining insight into the method of the movement of individual particles during the flow.

A comparison study on the antibacterial efficiency of essential oil and dried powder of Ocimum basilicum in ground beef during refrigerated storage

Directory of Open Access Journals (Sweden)

shohreh Dadfar

2014-09-01

Conclusion: The results indicated that both essential oil and dried powder of Ocimum basilicum increased the microbial stability of ground meat during storage, whereas dried powder showed more preservative capability at final days of storage. So it is possible to use this kind of natural product instead of synthetic one to reduce the disease of consumers and enhancing the organoleptic features of food

Device for preparing combinatorial libraries in powder metallurgy.

Science.gov (United States)

Yang, Shoufeng; Evans, Julian R G

2004-01-01

This paper describes a powder-metering, -mixing, and -dispensing mechanism that can be used as a method for producing large numbers of samples for metallurgical evaluation or electrical or mechanical testing from multicomponent metal and cermet powder systems. It is designed to make use of the same commercial powders that are used in powder metallurgy and, therefore, to produce samples that are faithful to the microstructure of finished products. The particle assemblies produced by the device could be consolidated by die pressing, isostatic pressing, laser sintering, or direct melting. The powder metering valve provides both on/off and flow rate control of dry powders in open capillaries using acoustic vibration. The valve is simple and involves no relative movement, avoiding seizure with fine powders. An orchestra of such valves can be arranged on a building platform to prepare multicomponent combinatorial libraries. As with many combinatorial devices, identification and evaluation of sources of mixing error as a function of sample size is mandatory. Such an analysis is presented.

Solid-state interactions between trimethoprim and parabens

DEFF Research Database (Denmark)

Pedersen, S.; Kristensen, H. G.; Cornett, Claus

1994-01-01

by differential scanning calorimetry, X-ray powder diffraction, Fourier transform infrared spectroscopy, and solid-state C-13-NMR. Interactions between trimethoprim and 4-hydroxybenzoic acid and its ethyl,propyl and butyl esters were not observed. The nature of the trimethoprim and methyl parahydroxybenzoate...

Preparation procedure for spherical titanium powders by RF induction plasma

International Nuclear Information System (INIS)

Gu Zhongtao; Jin Yuping; Ye Gaoying

2011-01-01

The paper uses the single-factor method for the study of spherical titanium powder preparation process. Titanium powders with excellent sphericity can be prepared through controlling and regulating the radio frequency plasma anode working current and voltage, central gas flow rate, sheath gas flow rate, powder-carrying gas flow rate, negative ventilation pressure and powder feed rate, etc. Spheroidization of titanium powders with a size of (17.0±2.0) μm is performed by radio frequency plasma technology. With the increase of negative ventilation pressure, the spheroidization rate of titanium powders increases firstly and then decreases rapidly at the turning point around 1800 Pa. With the rate of powder feed increasing, the spheroidization rate of titanium powders increases firstly. When the powder feed rate is greater than 90.0 g/min, the spheroidization rate of titanium powders reduces rapidly as the powder feed rate increases. (authors)

Concept and nuclear performance of direct-enrichment fusion breeder blanket using UO2 powder

International Nuclear Information System (INIS)

Oka, Yoshiaki; Kasahara, Takayasu; An, Shigehiro

1985-01-01

A new concept is presented for direct enrichment of fissile fuel in the blanket of a fusion-fission hybrid reactor. The enriched fuel produced by this means can be used in fission reactors without reprocessing. The outstanding feature of the concept is the powdered form in which UO 2 fuel is placed in the reactor blanket, where it is irradiated to the requisite enrichment for use as fuel in burner reactor, e.g. 3%. After removal from blanket, the powder is mixed to homogenize the enrichment. Fuel pellets and assemblies are then fabricated from the powder without reprocessing. The concept of irradiating UO 2 in powder eliminates the problems of spatial nonuniformity in fissile enrichment, and of radiation damage to fuel clad, encountered in attempting to enrich prefabricated fuel. Powder mixing for homogenization brings the additional benefit of removing volatile fission products. Also burnable poison can be added, as necessary, after irradiation. An extensive neutronic parameter survey showed that the optimum blanket arrangement for this enrichment concept is one presenting a fission suppressing configuration and with beryllium adopted as moderator. By this arrangement, the average 239 Pu enrichment obtained on the natural UO 2 fuel in the blanket reaches 3% after only 0.56 MW.yr/m"2 exposure. A conceptual design is presented of the blanket, together with associated fusion breeder, from which, practical application of the concept is shown to be promising. (author)

Silicon Nitride Photonic Integration Platforms for Visible, Near-Infrared and Mid-Infrared Applications

Science.gov (United States)

Micó, Gloria; Pastor, Daniel; Pérez, Daniel; Doménech, José David; Fernández, Juan; Baños, Rocío; Alemany, Rubén; Sánchez, Ana M.; Cirera, Josep M.; Mas, Roser

2017-01-01

Silicon nitride photonics is on the rise owing to the broadband nature of the material, allowing applications of biophotonics, tele/datacom, optical signal processing and sensing, from visible, through near to mid-infrared wavelengths. In this paper, a review of the state of the art of silicon nitride strip waveguide platforms is provided, alongside the experimental results on the development of a versatile 300 nm guiding film height silicon nitride platform. PMID:28895906

Electrical conductivity of metal powders under pressure

Science.gov (United States)

Montes, J. M.; Cuevas, F. G.; Cintas, J.; Urban, P.

2011-12-01

A model for calculating the electrical conductivity of a compressed powder mass consisting of oxide-coated metal particles has been derived. A theoretical tool previously developed by the authors, the so-called `equivalent simple cubic system', was used in the model deduction. This tool is based on relating the actual powder system to an equivalent one consisting of deforming spheres packed in a simple cubic lattice, which is much easier to examine. The proposed model relates the effective electrical conductivity of the powder mass under compression to its level of porosity. Other physically measurable parameters in the model are the conductivities of the metal and oxide constituting the powder particles, their radii, the mean thickness of the oxide layer and the tap porosity of the powder. Two additional parameters controlling the effect of the descaling of the particle oxide layer were empirically introduced. The proposed model was experimentally verified by measurements of the electrical conductivity of aluminium, bronze, iron, nickel and titanium powders under pressure. The consistency between theoretical predictions and experimental results was reasonably good in all cases.

Study of nuclear fuel powders forming by axial compaction

International Nuclear Information System (INIS)

Fourcade, J.

2002-12-01

Nuclear fuel powders forming, although perfectly dominated, fail to make compacts without density gradients. Density heterogeneities induce diametric deformations during firing which force manufacturers to adjust shape with a high cost machining stage. Manufacturing process improvement is a major project to obtain perfectly shaped pellets and reduce their cost. One way of investigation of this project is the study of powders compaction mechanisms to understand and improve their behaviour. The goal of this study is to identify the main mechanisms linked with powder properties that act on pressing. An empirical model is developed to predict pellet deformations from a single compaction test. This model has to link powder properties with their compaction behaviour. Then, compaction tests identify the main mechanisms whereas a contact dynamic program is used to explain them. These works, done to improve the understanding in powders behaviour, focus on powders agglomeration state and macroscopic particles arrangement during the die filling stage. Actually, for granulated powders, granules cohesion act on the powder bed behaviour under pressure. The first particles arrangement is responsible for the first transfer directions into the powder and so for its transfer homogeneity and isotropy. As a consequence, the knowledge of all the macroscopic powder properties is essential to understand and improve the manufacturing process. Moreover, tests on UO 2 powders have shown that it is better to use granulated powders with spherical granules, short size distribution and granules cohesion according with compaction pressure to improve compact homogeneity of densification. (author)

Infrared characterization of environmental samples by pulsed photothermal spectroscopy

International Nuclear Information System (INIS)

Seidel, W.; Foerstendorf, H.; Heise, K.H.; Nicolai, R.; Schamlott, A.; Ortega, J.M.; Glotin, F.; Prazeres, R.

2004-01-01

Low concentration of toxic radioactive metals in environmental samples often limits the interpretation of results of infrared studies investigating the interaction processes between the metal ions and environmental compartments. For the first time, we could show that photothermal infrared spectroscopy performed with a pulsed free electron laser can provide reliable infrared spectra throughout a distinct spectral range of interest. In this model investigation, we provide vibrational absorption spectra of a rare earth metal salt dissolved in a KBr matrix and a natural calcite sample obtained by photothermal beam deflection (PTBD) technique and FT-IR (Fourier-transform infrared) spectroscopy, respectively. General agreement was found between all spectra of the different recording techniques. Spectral deviations were observed with samples containing low concentration of the rare earth metal salt indicating a lower detection limit of the photothermal method as compared to conventional FT-IR spectroscopy. (authors)

Radiotreated cocoa powder for frozen elaboration

International Nuclear Information System (INIS)

Rodriguez Jorge, M.; Alvarez Gil, M.; Prieto Miranda, E.; Morales Valladares, M.

1995-01-01

The aim of the present papers is to study the possibilities of 2.0 kGy gamma radiotreated cocoa powder to be used in the elaboration of powder mixture for the preparation of chocolate frozen. Three industrial productions were carried out. Microbiological and organoleptic evaluations of the final product were performed. The results showed that the use of radurized cocoa powder in the frozen elaboration is feasible. A good hygienic quality of this product was obtained and no organoleptic alterations were detected [es

Random lasing in Nd{sup 3+} doped potassium gadolinium tungstate crystal powder

Energy Technology Data Exchange (ETDEWEB)

Moura, André L., E-mail: andre.moura@fis.ufal.br [Grupo de Física da Matéria Condensada, Núcleo de Ciências Exatas – NCEx, Campus Arapiraca, Universidade Federal de Alagoas, 57309-005, Arapiraca, AL (Brazil); Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife, PE (Brazil); Fewo, Serge I. [Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife, PE (Brazil); Laboratory of Mechanics, Department of Physics, University of Yaoundé I, Yaoundé (Cameroon); Carvalho, Mariana T.; Gomes, Anderson S. L.; Araújo, Cid B. de [Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife, PE (Brazil); Kuzmin, Andrey N.; Prasad, Paras N. [Institute for Lasers, Photonics and Biophotonics, The State University of New York, Buffalo, New York 14260-3000 (United States)

2015-02-28

Random laser (RL) emission in Nd{sup 3+} doped potassium gadolinium tungstate—KGd(WO{sub 4}){sub 2}:Nd{sup 3+}—crystal powder is demonstrated. The powder was excited at 813 nm in resonance with the Nd{sup 3+} transition {sup 4}I{sub 9/2}→{sup 4}F{sub 5/2}. RL emission at 1067 nm due to the {sup 4}F{sub 3/2}→{sup 4}I{sub 11/2} transition was observed and characterized. An intensity threshold dependent on the laser spot area and bandwidth narrowing from ≈2.20 nm to ≈0.40 nm were observed and measured. For a beam spot area of 0.4 mm{sup 2}, a RL threshold of 6.5 mJ/mm{sup 2} (90 MW/cm{sup 2}) was determined. For excitation intensity smaller than the RL threshold, only spontaneous emission from level {sup 4}F{sub 3/2} with decay time in the tens microsecond range was observed, but for excitation above the RL threshold, significant shortening of excited level lifetime, characteristic of a stimulated process was found. The overall characteristics measured show that KGd(WO{sub 4}){sub 2}:Nd{sup 3+} is an efficient material for operation of solid state RLs in the near-infrared.

Comparative study on strength properties of cement mortar by partial replacement of cement with ceramic powder and silica fume

Science.gov (United States)

Himabindu, Ch.; Geethasri, Ch.; Hari, N.

2018-05-01

Cement mortar is a mixture of cement and sand. Usage of high amount of cement increases the consumption of natural resources and electric power. To overcome this problem we need to replace cement with some other material. Cement is replaced with many other materials like ceramic powder, silica fume, fly ash, granulated blast furnace slag, metakaolin etc.. In this research cement is replaced with ceramic powder and silica fume. Different combinations of ceramic powder and silica fume in cement were replaced. Cement mortar cubes of 1:3 grade were prepared. These cubes were cured under normal water for 7 days, 14days and 28 days. Compressive strength test was conducted for all mixes of cement mortar cubes.

Preparation and utilization of metal oxide fine powder

Energy Technology Data Exchange (ETDEWEB)

Kim, Joon Soo; Jang, Hee Dong; Lim, Young Woong; Kim, Sung Don; Lee, Hi Sun; Lee, Hoo In; Kim, Chul Joo; Shim, Gun Joo; Jang, Dae Kyu [Korea Inst. of Geology Mining and Materials, Taejon (Korea, Republic of)

1995-12-01

Metal oxide fine powders finds many applications in industry as new materials. It is very much necessary for the development of such powders to improve the domestic industry. The purpose of present research is to develop a process for the preparation and utilization of metal oxide fine powder. This project is consisted of two main subjects. (1) Production of ultrafine metal oxide powder: Ultrafine metal oxide powder is defined as a metal oxide powder of less than 100 nanometer in particle size. Experiments for the control of particle size and distributions in the various reaction system and compared with results of (2 nd year research). Various reaction systems were adopted for the development of feasible process. Ultrafine particles could be prepared even higher concentration of TiCl{sub 4} and lower gas flowrate compared to TiCl{sub 4}-O{sub 2} system in the TiCl{sub 4}-Air-H{sub 2}O system. Ultrafine Al{sub 2}O{sub 3} powders also prepared with the change of concentration and gas flowrate. Experiments on the treatment of surface characteristics of ultrafine TiO{sub 2} powders were investigated using esterification and surface treating agents. A mathematical model that can predict the particle size and distribution was also developed. (2) Preparation of cerium oxide for high-grade polishing powder: Used cerium polishing powder was recycled for preparation of high grade cerium oxide polishing powder. Also, cerium hydroxide which was generated as by-product in processing of monazite ore was used as another material. These two materials were leached respectively by using acid, and the precipitate was gained in each leached solution by adjusting pH of the solution, and by selective crystallization. These precipitates were calcined to make high grade cerium oxide polishing powder. The effect of several experimental variables were investigated, and the optimum conditions were obtained through the experiments. (author). 81 refs., 49 figs., 27 tabs.

21 CFR 169.182 - Vanilla-vanillin powder.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Vanilla-vanillin powder. 169.182 Section 169.182... Dressings and Flavorings § 169.182 Vanilla-vanillin powder. (a) Vanilla-vanillin powder conforms to the... § 169.3(c) contained therein, the article also contains not more than 1 ounce of added vanillin. (b) The...

Shock-induced modification of inorganic powders

International Nuclear Information System (INIS)

Graham, R.A.; Morosin, B.; Venturini, E.L.; Beauchamp, E.K.; Hammetter, W.F.

1984-01-01

The results of studies performed to quantify the characteristics of TiO2, ZrO2 and Si3N4 powders exposed to explosive loading and post-shock analysis are reported. The shocks were produced with plane wave generators and explosive pads impinging on steel disks, a copper recovery fixture, and then the samples. Peak pressures of 13 and 17 GPa were attained, along with 40 GPz at the center of the powder cavity. Data are provided on the changes occurring during the explosive densification and X-ray and paramagnetic studies of the products. Only fractured disks were obtained in the trials. The shock-treated materials were more free flowing than the original powders, which were fluffy. Post-shock annealing was a significant feature of the treated powders

[The species traceability of the ultrafine powder and the cell wall-broken powder of herbal medicine based on DNA barcoding].

Science.gov (United States)

Xiang, Li; Tang, Huan; Cheng, Jin-le; Chen, Yi-long; Deng, Wen; Zheng, Xia-sheng; Lai, Zhi-tian; Chen, Shi-lin

2015-12-01

Ultrafine powder and cell wall-broken powder of herbal medicine lack of the morphological characters and microscopic identification features. This makes it hard to identify herb's authenticity with traditional methods. We tested ITS2 sequence as DNA barcode in identification of herbal medicine in ultrafine powder and cell wall-broken powder in this study. We extracted genomic DNAs of 93 samples of 31 representative herbal medicines (28 species), which include whole plant, roots and bulbs, stems, leaves, flowers, fruits and seeds. The ITS2 sequences were amplified and sequenced bidirectionally. The ITS2 sequences were identified using Basic Local Alignment Search Tool (BLAST) method in the GenBank database and DNA barcoding system to identify the herbal medicine. The genetic distance was analyzed using the Kimura 2-parameter (K2P) model and the Neighbor-joining (NJ) phylogenetic tree was constructed using MEGA 6.0. The results showed that DNA can be extracted successfully from 93 samples and high quality ITS2 sequences can be amplified. All 31 herbal medicines can get correct identification via BLAST method. The ITS2 sequences of raw material medicines, ultrafine powder and cell wall-broken powder have same sequence in 26 herbal medicines, while the ITS2 sequences in other 5 herbal medicines exhibited variation. The maximum intraspecific genetic-distances of each species were all less than the minimum interspecific genetic distances. ITS2 sequences of each species are all converged to their standard DNA barcodes using NJ method. Therefore, using ITS2 barcode can accurately and effectively distinguish ultrafine powder and cell wall-broken powder of herbal medicine. It provides a new molecular method to identify ultrafine powder and cell wall-broken powder of herbal medicine in the quality control and market supervision.

Spark-plasma sintering and mechanical property of mechanically alloyed NiAl powder compact and ball-milled (Ni+Al) mixed powder compact

International Nuclear Information System (INIS)

Kim, J.S.; Jang, Y.I.; Kwon, Y.S.; Kim, Y.D.; Ahn, I.S.

2001-01-01

Mechanically-alloyed NiAl powder and (Ni+Al) powder mixture prepared by ball-milling were sintered by spark-plasma sintering (SPS) process. Densification behavior and mechanical property were determined from the experimental results and analysis such as changes in linear shrinkage, shrinkage rate, microstructure, and phase during sintering process, Vicker's hardness and transverse rupture strength tests. Densification mechanisms for MA-NiAl powder compact and (Ni+Al) powder mixture were different from each other. While the former showed a rapid increase in densification rate only at higher temperature region of 800-900 o C, the latter revealed firstly a rapid increase in densification rate even at low temperature of 300 o C and a subsequent increase up to 500 o C. Densities of both powder compact (MA and mixture) sintered at 1150 o C for 5 min were 98 and above 99 %, respectively. Sintered bodies were composed mainly of NiAl phase with Ni 3 Al as secondary phase for both powders. Sintered body of MA-NiAl powder showed a very fine grain structure. Crystallite size determined by XRD result and the Sherrer's equation was approximately 80 nm. Vicker's hardness for the sintered bodies of (Ni+Al) powder mixture and MA-NiAl powder were 410±12 H v and 555±10 H v , respectively, whereas TRS values 1097±48 MPa and 1393±75 MPa. (author)

Mechanochemical synthesis of fluorescent carbon dots from cellulose powders

Science.gov (United States)

Chae, Ari; Ram Choi, Bo; Choi, Yujin; Jo, Seongho; Kang, Eun Bi; Lee, Hyukjin; Park, Sung Young; In, Insik

2018-04-01

A novel mechanochemical method was firstly developed to synthesize carbon nanodots (CNDs) or carbon nano-onions (CNOs) through high-pressure homogenization of cellulose powders as naturally abundant resource depending on the treatment times. While CNDs (less than 5 nm in size) showed spherical and amorphous morphology, CNOs (10-50 nm in size) presented polyhedral shape, and onion-like outer lattice structure, graphene-like interlattice spacing of 0.36 nm. CNOs showed blue emissions, moderate dispersibility in aqueous media, and high cell viability, which enables efficient fluorescence imaging of cellular media.

Electro/powder separation process

International Nuclear Information System (INIS)

Dunn, J.P.

1977-01-01

A report is presented to introduce the ELECTRO/POWDER process to the P/M Industry. The process effectively uses electrostatic forces to convey, sort, meter, and blend fine powders. The major advantages of this separating process consist of the processing of primary particles, low particle energy due to particle velocity control and the pattern of particle movement over the sieve (vertical oscillation of particles above the sieve aperture). The report briefly describes the forces involved in both mechanical and sieving devices, with major emphasis on the operating principles of this process. Sieve separation of particulates is basically the result of two physical separating processes which occur simultaneously or independently; separation (dispersion) of particulates from each other and the size separation by passage through fixed apertures. In order to accomplish this goal, mechanical sieving devices utilize various motions to induce shear forces between the sieve surface and the particulates, and between the particulates themselves. It is noted that the ELECTRO/POWDER process is making steady progress in becoming an industrial tool for sieving and feeding of fine particles. Its potential extends into both the blending and admixing of powders, either by incorporating two opposing feeders, one being charged with the opposite polarity or by modifying the ELECTRO/SIEVE to incorporate more than one input and a solid electrode to replace the sieve electrode

The infrared spectrum of Jupiter

Science.gov (United States)

Ridgway, S. T.; Larson, H. P.; Fink, U.

1976-01-01

The principal characteristics of Jupiter's infrared spectrum are reviewed with emphasis on their significance for our understanding of the composition and temperature structure of the Jovian upper atmosphere. The spectral region from 1 to 40 microns divides naturally into three regimes: the reflecting region, thermal emission from below the cloud deck (5-micron hot spots), and thermal emission from above the clouds. Opaque parts of the Jovian atmosphere further subdivide these regions into windows, and each is discussed in the context of its past or potential contributions to our knowledge of the planet. Recent results are incorporated into a table of atmospheric composition and abundance which includes positively identified constituents as well as several which require verification. The limited available information about spatial variations of the infrared spectrum is presented

Fe-based nanocrystalline powder cores with ultra-low core loss

Energy Technology Data Exchange (ETDEWEB)

Wang, Xiangyue, E-mail: wangxiangyue1986@163.com [China Iron and Steel Research Institute Group, Beijing 100081 (China); Center of Advanced Technology and Materials Co., Ltd., Beijing 100081 (China); Lu, Zhichao; Lu, Caowei; Li, Deren [China Iron and Steel Research Institute Group, Beijing 100081 (China); Center of Advanced Technology and Materials Co., Ltd., Beijing 100081 (China)

2013-12-15

Melt-spun amorphous Fe{sub 73.5}Cu{sub 1}Nb{sub 3}Si{sub 15.5}B{sub 7} alloy strip was crushed to make flake-shaped fine powders. The passivated powders by phosphoric acid were mixed with organic and inorganic binder, followed by cold compaction to form toroid-shaped bonded powder-metallurgical magnets. The powder cores were heat-treated to crystallize the amorphous structure and to control the nano-grain structure. Well-coated phosphate-oxide insulation layer on the powder surface decreased the the core loss with the insulation of each powder. FeCuNbSiB nanocrystalline alloy powder core prepared from the powder having phosphate-oxide layer exhibits a stable permeability up to high frequency range over 2 MHz. Especially, the core loss could be reduced remarkably. At the other hand, the softened inorganic binder in the annealing process could effectively improve the intensity of powder cores. - Highlights: • Fe-based nanocrystalline powder cores were prepared with low core loss. • Well-coated phosphate-oxide insulation layer on the powder surface decreased the core loss. • Fe-based nanocrystalline powder cores exhibited a stable permeability up to high frequency range over 2 MHz. • The softened inorganic binder in the annealing process could effectively improve the intensity of powder cores.

Preparation of superconducting powders by freeze-drying

International Nuclear Information System (INIS)

Johnson, S.M.; Gusman, M.I.; Rowcliffe, D.J.; Geballe, T.H.; Sun, J.Z.

1987-01-01

A method of preparing superconducting powders by freeze-drying is described. Powders produced by this method are homogeneous, have high purities, and are very reactive. Materials sintered from these powders have densities up to 89% of the theoretical density, and exhibit very sharp resistivity drops and large Meissner effects. The microstructure of the materials is very sensitive to the sintering temperature

Food powders flowability characterization: theory, methods, and applications.

Science.gov (United States)

Juliano, Pablo; Barbosa-Cánovas, Gustavo V

2010-01-01

Characterization of food powders flowability is required for predicting powder flow from hoppers in small-scale systems such as vending machines or at the industrial scale from storage silos or bins dispensing into powder mixing systems or packaging machines. This review covers conventional and new methods used to measure flowability in food powders. The method developed by Jenike (1964) for determining hopper outlet diameter and hopper angle has become a standard for the design of bins and is regarded as a standard method to characterize flowability. Moreover, there are a number of shear cells that can be used to determine failure properties defined by Jenike's theory. Other classic methods (compression, angle of repose) and nonconventional methods (Hall flowmeter, Johanson Indicizer, Hosokawa powder tester, tensile strength tester, powder rheometer), used mainly for the characterization of food powder cohesiveness, are described. The effect of some factors preventing flow, such as water content, temperature, time consolidation, particle composition and size distribution, is summarized for the characterization of specific food powders with conventional and other methods. Whereas time-consuming standard methods established for hopper design provide flow properties, there is yet little comparative evidence demonstrating that other rapid methods may provide similar flow prediction.

Exploring Oven-drying Technique in Producing Pineapple Powder

Directory of Open Access Journals (Sweden)

Cyril John A. Domingo

2017-11-01

Full Text Available Pineapple puree and juice of 11 to 12 °Brix were used to obtain pineapple powder using oven-drying technique. Addition of maltodextrin in treatments 2 and 4 yielded good quality powder, however addition of sugar and maltodextrin in treatments 1 and 3 resulted to sticky product which was processed to pineapple leather. Treatment 2 composed of pineapple puree and maltodextrin resulted to significantly higher powder recovery compared with treatment 4 which composed of pineapple juice and maltodextrin. The solubility of pineapple powder improved as maltodextrin concentration is increased from 40.00 % to 60.00 %.Addition of maltodextrin also reduced stickiness of the final product. An instant pineapple powder of 5.47 and 5.33 % moisture content could be produced by oven-drying.This level of moisture content will prohibit bacterial growth in the pineapple powder but may have mold or yeast growth with increase storage period at environments with high humidity. Molds were observed on the 17th day at 89.00 % relative humidity as exhibited by the moisture sorption isotherm data. This suggests that appropriate packaging with moisture barrier is recommended for pineapple powder. This study showedthat by using appropriate ratio of juice, puree, and maltodextrin and appropriate oven drying conditions, a good oven-dried pineapple powder could be obtained.

Ternary ceramic thermal spraying powder and method of manufacturing thermal sprayed coating using said powder

Energy Technology Data Exchange (ETDEWEB)

Vogli, Evelina; Sherman, Andrew J.; Glasgow, Curtis P.

2018-02-06

The invention describes a method for producing ternary and binary ceramic powders and their thermal spraying capable of manufacturing thermal sprayed coatings with superior properties. Powder contain at least 30% by weight ternary ceramic, at least 20% by weight binary molybdenum borides, at least one of the binary borides of Cr, Fe, Ni, W and Co and a maximum of 10% by weight of nano and submicro-sized boron nitride. The primary crystal phase of the manufactured thermal sprayed coatings from these powders is a ternary ceramic, while the secondary phases are binary ceramics. The coatings have extremely high resistance against corrosion of molten metal, extremely thermal shock resistance and superior tribological properties at low and at high temperatures.

The quantitative characterization of sintering of urania powders

International Nuclear Information System (INIS)

Das, P.; Kulkarni, U.D.

1981-01-01

This paper presents a unified approach towards characterization of the sintering behaviour of UO 2 powders in terms of their extrinsic properties. Empirical equations connecting the sintering index with various powder parameters have been set up. The influence of various powder parameters, either individually or as dimensionless/dimensional groups, on the sintering behaviour has been studied. The relative importance of these factors has also been analysed. A good polynomial fit has been obtained for variation of sintering index with some of the powder parameters and dimensionless/dimensional groups. The equations are expected to provide a good basis for assessing the sinterability of UO 2 powders. (Auth.)

Characterization and Sintering of Armstrong Process Titanium Powder

Science.gov (United States)

Xu, Xiaoyan; Nash, Philip; Mangabhai, Damien

2017-04-01

Titanium and titanium alloys have a high strength to weight ratio and good corrosion resistance but also need longer time and have a higher cost on machining. Powder metallurgy offers a viable approach to produce near net-shape complex components with little or no machining. The Armstrong titanium powders are produced by direct reduction of TiCl4 vapor with liquid sodium, a process which has a relatively low cost. This paper presents a systematic research on powder characterization, mechanical properties, and sintering behavior and of Armstrong process powder metallurgy, and also discusses the sodium issue, and the advantages and disadvantages of Armstrong process powders.

Comparison between solid-state and powder-state alkali pretreatment on saccharification and fermentation for bioethanol production from rice straw.

Science.gov (United States)

Yeasmin, Shabina; Kim, Chul-Hwan; Islam, Shah Md Asraful; Lee, Ji-Young

2016-01-01

The efficacy of different concentrations of NaOH (0.25%, 0.50%, 0.75%, and 1.00%) for the pretreatment of rice straw in solid and powder state in enzymatic saccharification and fermentation for the production of bioethanol was evaluated. A greater amount of biomass was recovered through solid-state pretreatment (3.74 g) from 5 g of rice straw. The highest increase in the volume of rice straw powder as a result of swelling was observed with 1.00% NaOH pretreatment (48.07%), which was statistically identical to 0.75% NaOH pretreatment (32.31%). The surface of rice straw was disrupted by the 0.75% NaOH and 1.00% NaOH pretreated samples as observed using field-emission scanning electron microscopy (FE-SEM) and atomic force microscopy (AFM). In Fourier-transform infrared (FT-IR) spectra, absorbance of hydroxyl groups at 1,050 cm(-1) due to the OH group of lignin was gradually decreased with the increase of NaOH concentration. The greatest amounts of glucose and ethanol were obtained in 1.00% NaOH solid-state pretreated and powder-state hydrolyzed samples (0.804 g g(-1) and 0.379 g g(-1), respectively), which was statistically similar to the use of 0.75% NaOH (0.763 g g(-1) and 0.358 g g(-1), respectively). Thus, solid-state pretreatment with 0.75% NaOH and powder-state hydrolysis appear to be suitable for fermentation and bioethanol production from rice straw.

Effect of Tara (Caesalpinia spinosa Pod Powder on the Oxidation and Colour Stability of Pork Meat Batter During Chilled Storage

Directory of Open Access Journals (Sweden)

Monika Skowyra

2015-01-01

Full Text Available The eff ect of dried pods of Caesalpinia spinosa, known as tara, on pH, cooking loss, lipid oxidation, colour stability and texture of model meat systems stored at 4 °C for 21 days was investigated. Tara pod powder showing a potential antioxidant activity was added at 0.02, 0.04 and 0.08 % (by mass directly to the pork batt er and compared with a synthetic antioxidant, butylated hydroxyanisole (BHA and control (no added antioxidants. The addition of tara pod powder at 0.02 % was as effective as BHA (0.02 % in retarding lipid oxidation in pork products during storage. Results showed that redness increased after the addition of tara pod powder. Specifically, 0.02 % of tara pod powder was effective in keeping the red colour of meat batter stored under illumination at 4 °C for 48 h. Hardness of pork products was the lowest in samples manufactured with tara pod powder compared with control. Results highlight the potential of using tara pod powder as natural functional ingredient in the development of pork products with enhanced quality and shelf life.

Strain-enhanced sintering of iron powders

Energy Technology Data Exchange (ETDEWEB)

Amador, D.R.; Torralba, J.M. [Universidad Carlos III de Madrid, Departamento de Ciencias de Materiales e Ingenieria Metalurgica, Leganes, Madrid (Spain); Monge, M.A.; Pareja, R. [Universidad Carlos III de Madrid, Departamento de Fisica, Madrid (Spain)

2005-02-01

Sintering of ball-milled and un-milled Fe powders has been investigated using dilatometry, X-ray, density, and positron annihilation techniques. A considerable sintering enhancement is found in milled powders showing apparent activation energies that range between 0.44 and 0.80 eV/at. The positron annihilation results, combined with the evolution of the shrinkage rate with sintering temperature, indicate generation of lattice defects during the sintering process of milled and un-milled powders. The sintering enhancement is attributed to pipe diffusion along the core of moving dislocations in the presence of the vacancy excess produced by plastic deformation. Positron annihilation results do not reveal the presence of sintering-induced defects in un-milled powders sintered above 1200 K, the apparent activation energy being in good agreement with that for grain-boundary diffusion in {gamma}-Fe. (orig.)

Powder diffractometry

International Nuclear Information System (INIS)

Doucet, J.

1983-01-01

The new possibilities openned by the synchrotron radiation in the powder diffractometry techniques are presented. This technique is described in a general manner and some aspects which can be developed with the use of the synchrotron radiation are analyzed. (L.C.) [pt

Effect of salt, kinnow and pomegranate fruit by-product powders on color and oxidative stability of raw ground goat meat during refrigerated storage.

Science.gov (United States)

Devatkal, Suresh K; Naveena, B M

2010-06-01

Effects of salt, kinnow and pomegranate fruit by-product powders on color and oxidative stability of raw ground goat meat stored at 4+/-1 degrees C was evaluated. Five treatments evaluated include: control (only meat), MS (meat+2% salt), KRP (meat+2% salt+2% kinnow rind powder), PRP (meat+2% salt+2% pomegranate rind powder) and PSP (meat+2% salt+2% pomegranate seed powder). Addition of salt resulted in reduction of redness scores. Lightness increased in control and unchanged in others during storage. Redness scores declined and yellowness showed inconsistent changes during storage. Thiobarbituric acid reactive substances (TBARS) values were higher (PPRP>KRP>control>MS. Therefore, these powders have potential to be used as natural antioxidants to minimize the auto-oxidation and salt induced lipid oxidation in raw ground goat meat. Crown Copyright 2010. Published by Elsevier Ltd. All rights reserved.

Powder metallurgy techniques in nuclear technology

International Nuclear Information System (INIS)

Mardon, P.G.

1983-01-01

The nuclear application of conventional powder metallurgy routes is centred on the fabrication of ceramic fuels. The stringent demands in terms of product performance required by the nuclear industry militate against the use of conventional powder metallurgy to produce metallic components such as the fuel cladding. However, the techniques developed in powder metallurgy find widespread application throughout nuclear technology. Illustrations of the use of these techniques are given in the fields of absorber materials, ceramic cladding materials, oxide fuels, cermet fuels, and the disposal of highly active waste. (author)

Plasma metallization of refractory carbide powders

International Nuclear Information System (INIS)

Koroleva, E.B.; Klinskaya, N.A.; Rybalko, O.F.; Ugol'nikova, T.A.

1986-01-01

The effect of treatment conditions in plasma on properties of produced metallized powders of titanium, tungsten and chromium carbides with the main particle size of 40-80 μm is considered. It is shown that plasma treatment permits to produce metallized powders of carbide materials with the 40-80 μm particle size. The degree of metallization, spheroidization, chemical and phase composition of metallized carbide powders are controlled by dispersivity of the treated material, concentration of a metal component in the treated mixtures, rate of plasma flow and preliminary spheroidization procedure

Net shape powder processing of aluminium

International Nuclear Information System (INIS)

Schaffer, G.B.

2000-01-01

The increasing interest in light weight materials coupled to the need for cost-effective processing have combined to create a significant opportunity for aluminium powder metallurgy. Net shape processing of aluminium using the classical press-and-sinter powder metallurgy technique is a unique and important metal-forming method which is cost effective in producing complex parts at, or very close to, final dimensions. This paper provides an overview of the net shape powder processing of aluminium. Current research is critically reviewed and the future potential is briefly considered

Characterization of UO2 by infrared spectroscopy

International Nuclear Information System (INIS)

Faeda, Kelly C.M.; Machado, Geraldo C.; Lameiras, Fernando S.

2011-01-01

The characterization of nuclear fuel is of great importance to minimize the effects related to burnup and temperature and to achieve stability during in-core operation. The understanding the U-O system and its thermodynamic properties has fundamental importance in nuclear industry. Many physical properties of UO 2±x depend on the ratio O / U, such as the electrical conductivity and thermal properties, as well as the diffusivities of its constituents and solutes. The U-O system presents various oxides such as UO 2±x , U 4 O 9 , U 3 O 8 , and UO 3 . The control of the O/U relation is critical to the manufacturing process of UO 2 . In this work, the infrared spectroscopy was used to identify the presence of phases in UO 2 powder samples that cannot be identified by thermogravimetry and X-ray diffraction. (author)

[Determination of steviol in Stevia Rebaudiana leaves by near infrared spectroscopy].

Science.gov (United States)

Tang, Qi-Kun; Wang, Yul; Wu, Yue-Jin; Min, Di; Chen, Da-Wei; Hu, Tong-Hua

2014-10-01

The objective of the present study is to develop a method for rapid determination of the content of stevioside (ST) and rebaudioside A (RA) in Stevia Rebaudiana leaves. One hundred and five samples of stevia from different areas containing ST of 0.27%-1.40% and RA of 0.61%-3.98% were used. The 105 groups' NIRS diagram was processed by different methods including subtracting a straight line (SLS), multiplicative scatter correction (MSC), first derivative (FD), second derivative (SD) and so on, and then all data were analyzed by partial least square (PLS). The study showed that SLS can be used to extracted spectra information thoroughly to analyze the contents of ST, the correlation coefficients of calibration (Re), the root-mean-square errors of calibration (RMSEC) and prediction (RMSEP), and the residual predictive deviation (RPD) were 0.986, 0.341, 1.00 and 2.8, respectively. The correlation coefficients of RA was 0.967, RMSEC was 1.50, RMSEP was 1.98 and RPD was 4.17. The results indicated that near infrared spectroscopy (NIRS) technique offers effective quantitative capability for ST and RA in Stevia Rebaudiana leaves. Then the model of stevia dried leaves was used to compare with the stevia powder near infrared model whose correlation coefficients of ST was 0.986, RMSEC was 0.32, RMSEP was 0.601 and RPD was 2.86 and the correlation coefficients of RA was 0.968, RMSEC was 1.50, RMSEP was 1.48 and RPD was 4.2. The result showed that there was no significant difference between the model of dried leaves and that of the powders. However, the dried leaves NIR model reduces the unnecessary the steps of drying and grinding in the actual detection process, saving the time and reducing the workload.

Application of permanent magnets made from NdFeB powder and from mixtures of powders in DC motors

International Nuclear Information System (INIS)

Slusarek, B.; Dudzikowski, I.

2002-01-01

The paper presents the influence of magnetic properties of applied permanent magnets on the characteristics of DC motors excited with these magnets. In the factory-produced DC motors, excited with sintered ferrite magnets, authors replaced ferrite magnets with the dielectromagnets from NdFeB powder and from different mixtures of NdFeB and ferrite powders. The paper shows the increase of the power of the resultant DC motors according to the powders' content

Periodic Spacing of Protocluster Clumps in a Filamentary Infrared Dark Cloud

Science.gov (United States)

Jackson, James M.; Finn, S.; Rathborne, J. M.; Simon, R.

2010-05-01

The ''Nessie'' nebula is an extremely filamentary infrared dark cloud, with an aspect ratio of over 300:1. HNC 1-0 observations with the Australia Telescope National Facility's Mopra Telescope demonstrate that Nessie is a single, coherent cloud with high densities (n > 105 cm-3). The filamentary cloud contains a number of protocluster clumps with a nearly regular, periodic spacing of 5 pc. Such clumps naturally arise from the ''varicose'' fluid instability of a self-gravitating fluid cylinder. Because of the ubiquitous association between massive clusters and filamentary molecular clouds (e.g., Orion, NGC 6334, etc.), we speculate that clusters naturally arise from filamentary infrared dark clouds via fluid instabilities.

USING OF THE MULTITEMPORAL THERMAL INFRARED SATELLITE IMAGERY FOR NATURAL AREAS MAPPING (CASE OF MENDELEEV VOLCANO

Directory of Open Access Journals (Sweden)

M. Y. Grishchenko

2014-01-01

Full Text Available In the paper authors examine the mountain group of Mendeleev volcano situated on the Kunashir island, Kuril archipelago, Russia. Ground observations were led to examine the vegetation cover of the area as well as its typical landscapes. The other type of used data is Landsat imagery. Images were combined into multitemporal thermal infrared and multispectral pictures, which were classified to reveal the heterogeneity of the study area. Ground observations and comparison of the classification results with landscape map derive that the multitemporal thermal infrared image classification result describes better the vegetation cover structure of the area and particularity of its typical landscapes distribution. It leads to the proposition that miltitemporal thermal infrared imagery can be used to refine landscape and vegetation cover contours. 

Time resolved fluorescence of cow and goat milk powder

Science.gov (United States)

Brandao, Mariana P.; de Carvalho dos Anjos, Virgílio; Bell., Maria José V.

2017-01-01

Milk powder is an international dairy commodity. Goat and cow milk powders are significant sources of nutrients and the investigation of the authenticity and classification of milk powder is particularly important. The use of time-resolved fluorescence techniques to distinguish chemical composition and structure modifications could assist develop a portable and non-destructive methodology to perform milk powder classification and determine composition. This study goal is to differentiate milk powder samples from cows and goats using fluorescence lifetimes. The samples were excited at 315 nm and the fluorescence intensity decay registered at 468 nm. We observed fluorescence lifetimes of 1.5 ± 0.3, 6.4 ± 0.4 and 18.7 ± 2.5 ns for goat milk powder; and 1.7 ± 0.3, 6.9 ± 0.2 and 29.9 ± 1.6 ns for cow's milk powder. We discriminate goat and cow powder milk by analysis of variance using Fisher's method. In addition, we employed quadratic discriminant analysis to differentiate the milk samples with accuracy of 100%. Our results suggest that time-resolved fluorescence can provide a new method to the analysis of powder milk and its composition.

Slip casting nano-particle powders for making transparent ceramics

Science.gov (United States)

Kuntz, Joshua D [Livermore, CA; Soules, Thomas F [Livermore, CA; Landingham, Richard Lee [Livermore, CA; Hollingsworth, Joel P [Oakland, CA

2011-04-12

A method of making a transparent ceramic including the steps of providing nano-ceramic powders in a processed or unprocessed form, mixing the powders with de-ionized water, the step of mixing the powders with de-ionized water producing a slurry, sonifing the slurry to completely wet the powder and suspend the powder in the de-ionized water, separating very fine particles from the slurry, molding the slurry, and curing the slurry to produce the transparent ceramic.

Powder technology

International Nuclear Information System (INIS)

Agueda, Horacio

1989-01-01

Powder technology is experiencing nowadays a great development and has broad application in different fields: nuclear energy, medicine, new energy sources, industrial and home artifacts, etc. Ceramic materials are of daily use as tableware and also in the building industry (bricks, tiles, etc.). However, in machine construction its utilization is not so common. The same happens with metals: powder metallurgy is employed less than traditional metal forming techniques. Both cases deal with powder technology and the forming techniques as far as the final consolidation through sintering processes are very similar. There are many different methods and techniques in the forming stage: cold-pressing, slip casting, injection molding, extrusion molding, isostatic pressing, hot-pressing (which involves also the final consolidation step), etc. This variety allows to obtain almost any desired form no matter how complex it could be. Some applications are very specific as in the case of UO 2 pellets (used as nuclear fuels) but with the same technique and other materials, it is possible to manufacture a great number of different products. This work shows the characteristics and behaviour of two magnetic ceramic materials (ferrites) fabricated in the laboratory of the Applied Research Division of the Bariloche Atomic Center for different purposes. Other materials and products made with the same method are also mentioned. Likewise, densities and shrinkage obtained by different methods of forming (cold-pressing, injection molding, slip casting and extrusion molding) using high-purity alumina (99.5% Al 2 O 3 ). Finally, different applications of such methods are given. (Author) [es

Investigation of pressing of molybdenum powder compacts

International Nuclear Information System (INIS)

Mymrin, S.A.; Kuznetsov, V.Eh.; Yampol'skij, M.L.; Leonov, S.A.; Mikhridinov, R.M.; Korzukhin, V.A.

1990-01-01

Results of an experimental investigation into pressing of compacts of MCh type molybdenum powders using the industrial equipment are presented. To measure the density of powder molybdenum billets a radioisotopic density meter with cesium-137 is used as radioactive gamma radiation source. The dependence of the produced billet density on the specific compacting pressure at different values of the powder bulk density is ascertained

Cryomilling of Thermoplastic Powder for Prepreg Applications

Science.gov (United States)

2013-09-01

Cryomilling of Thermoplastic Powder for Prepreg Applications by Brian Parquette, Anit Giri, Daniel J. O’Brien, Sarah Brennan, Kyu Cho, and...MD 21005-5066 ARL-TR-6591 September 2013 Cryomilling of Thermoplastic Powder for Prepreg Applications Brian Parquette and Sarah Brennan...COVERED (From - To) 1 March 2012–30 May 2013 4. TITLE AND SUBTITLE Cryomilling of Thermoplastic Powder for Prepreg Applications 5a. CONTRACT

Cerebroprotective Actions of Triticum aestivum Linn Powder and Bauhinia purpurea Flower Powder in Surgically Induced Cerebral Infraction in Rats.

Science.gov (United States)

Annapurna, Akula; Vishala, Thonangi C; Bitra, Veera R; Rapaka, Deepthi; Shaik, Asmath

2018-01-01

The prime objective of this study is to evaluate the cerebroprotective actions of Triticum aestivum (wheatgrass) powder and Bauhinia purpurea flower (dev kanchan) powder against the experimentally induced global ischemia reperfusion injury in rats. In the first phase of the studies, 1 h before the surgical procedure, the Wistar rats were orally served with varied doses of wheatgrass powder (5, 10, 30, and 100 μg/kg) and Bauhinia flower powder (30, 100, 200, and 300 μg/kg), respectively. The ischemia was induced by 30-min bilateral carotid artery occlusion in succession to reperfusion for 4 h. It was proved that the wheatgrass powder and Bauhinia flower powder yielded a significant, dose-dependent cerebroprotection in terms of reduction in cerebral infarct size when compared with the control group. Coming to the second phase of the studies, a certain potential dose of 10 μg/kg of wheatgrass and 200 μg/kg of Bauhinia flower powders was selected keeping the protective action in view, and the animals were treated for 15 days. The major findings of the study are that wheatgrass and Bauhinia flower powders significantly augmented the magnitude of the antioxidant enzymes, viz., super oxide dismutase and catalase, and further reduced the levels of lipid peroxidation. The present study clearly showed that the wheatgrass powder and Bauhinia flower powder possess significant antioxidant properties that may act as a key ingredient in various ayurvedic preparations for the treatment of various diseases like cerebral ischemic reperfusion injury. The wheat grass contains high amount of bioflavonoids, alkaloids, SOD etc which are responsible for anti oxidant activity.The Bauhinia purpurea contains glycosides, flavonoids and also plays a major role in DPPH activity which is responsible for anti oxidant activity.The wheat grass (10 mg/kg) and bauhinia (200 mg/kg) significantly(P bauhinia (200 mg/kg) significantly (P <0.0001) reduced the lipid peroxidation (MDA) and increased SOD

Infrared

Science.gov (United States)

Vollmer, M.

2013-11-01

'Infrared' is a very wide field in physics and the natural sciences which has evolved enormously in recent decades. It all started in 1800 with Friedrich Wilhelm Herschel's discovery of infrared (IR) radiation within the spectrum of the Sun. Thereafter a few important milestones towards widespread use of IR were the quantitative description of the laws of blackbody radiation by Max Planck in 1900; the application of quantum mechanics to understand the rotational-vibrational spectra of molecules starting in the first half of the 20th century; and the revolution in source and detector technologies due to micro-technological breakthroughs towards the end of the 20th century. This has led to much high-quality and sophisticated equipment in terms of detectors, sources and instruments in the IR spectral range, with a multitude of different applications in science and technology. This special issue tries to focus on a few aspects of the astonishing variety of different disciplines, techniques and applications concerning the general topic of infrared radiation. Part of the content is based upon an interdisciplinary international conference on the topic held in 2012 in Bad Honnef, Germany. It is hoped that the information provided here may be useful for teaching the general topic of electromagnetic radiation in the IR spectral range in advanced university courses for postgraduate students. In the most general terms, the infrared spectral range is defined to extend from wavelengths of 780 nm (upper range of the VIS spectral range) up to wavelengths of 1 mm (lower end of the microwave range). Various definitions of near, middle and far infrared or thermal infrared, and lately terahertz frequencies, are used, which all fall in this range. These special definitions often depend on the scientific field of research. Unfortunately, many of these fields seem to have developed independently from neighbouring disciplines, although they deal with very similar topics in respect of the

Free radical interactions between raw materials in dry soup powder.

Science.gov (United States)

Raitio, Riikka; Orlien, Vibeke; Skibsted, Leif H

2011-12-01

Interactions at the free radical level were observed between dry ingredients in cauliflower soup powder, prepared by dry mixing of ingredients and rapeseed oil, which may be of importance for quality deterioration of such dry food products. The free radical concentrations of cauliflower soup powder, obtained by electron spin resonance (ESR) spectroscopy, rapidly become smaller during storage (40°C and relative humidity of 75%) than the calculated concentrations of free radicals based on the free radical concentrations of the powder ingredients used to make the soup powder and stored separately under similar conditions. Similarly, free radical concentrations decreased faster when any combination of two powder ingredients (of the three major ingredients of the soup powder) were mixed together and stored at 50°C for 1week than when each powder component was stored separately. Furthermore, yeast extract powder was found to play a key role when free radical interactions between powder ingredients occurred. The incubation of rapeseed oil with powder ingredients at 45°C for 24h, indicated the ability of cauliflower powder to increase the concentration of hydroperoxides in rapeseed oil, while yeast extract powder was found to prevent this hydroperoxide formation. Copyright © 2011 Elsevier Ltd. All rights reserved.

Characterization of Metal Powders Used for Additive Manufacturing.

Science.gov (United States)

Slotwinski, J A; Garboczi, E J; Stutzman, P E; Ferraris, C F; Watson, S S; Peltz, M A

2014-01-01

Additive manufacturing (AM) techniques can produce complex, high-value metal parts, with potential applications as critical parts, such as those found in aerospace components. The production of AM parts with consistent and predictable properties requires input materials (e.g., metal powders) with known and repeatable characteristics, which in turn requires standardized measurement methods for powder properties. First, based on our previous work, we assess the applicability of current standardized methods for powder characterization for metal AM powders. Then we present the results of systematic studies carried out on two different powder materials used for additive manufacturing: stainless steel and cobalt-chrome. The characterization of these powders is important in NIST efforts to develop appropriate measurements and standards for additive materials and to document the property of powders used in a NIST-led additive manufacturing material round robin. An extensive array of characterization techniques was applied to these two powders, in both virgin and recycled states. The physical techniques included laser diffraction particle size analysis, X-ray computed tomography for size and shape analysis, and optical and scanning electron microscopy. Techniques sensitive to structure and chemistry, including X-ray diffraction, energy dispersive analytical X-ray analysis using the X-rays generated during scanning electron microscopy, and X-Ray photoelectron spectroscopy were also employed. The results of these analyses show how virgin powder changes after being exposed to and recycled from one or more Direct Metal Laser Sintering (DMLS) additive manufacturing build cycles. In addition, these findings can give insight into the actual additive manufacturing process.

Characterization of Metal Powders Used for Additive Manufacturing

Science.gov (United States)

Slotwinski, JA; Garboczi, EJ; Stutzman, PE; Ferraris, CF; Watson, SS; Peltz, MA

2014-01-01

Additive manufacturing (AM) techniques1 can produce complex, high-value metal parts, with potential applications as critical parts, such as those found in aerospace components. The production of AM parts with consistent and predictable properties requires input materials (e.g., metal powders) with known and repeatable characteristics, which in turn requires standardized measurement methods for powder properties. First, based on our previous work, we assess the applicability of current standardized methods for powder characterization for metal AM powders. Then we present the results of systematic studies carried out on two different powder materials used for additive manufacturing: stainless steel and cobalt-chrome. The characterization of these powders is important in NIST efforts to develop appropriate measurements and standards for additive materials and to document the property of powders used in a NIST-led additive manufacturing material round robin. An extensive array of characterization techniques was applied to these two powders, in both virgin and recycled states. The physical techniques included laser diffraction particle size analysis, X-ray computed tomography for size and shape analysis, and optical and scanning electron microscopy. Techniques sensitive to structure and chemistry, including X-ray diffraction, energy dispersive analytical X-ray analysis using the X-rays generated during scanning electron microscopy, and X-Ray photoelectron spectroscopy were also employed. The results of these analyses show how virgin powder changes after being exposed to and recycled from one or more Direct Metal Laser Sintering (DMLS) additive manufacturing build cycles. In addition, these findings can give insight into the actual additive manufacturing process. PMID:26601040

Are the infrared-faint radio sources pulsars?

Science.gov (United States)

Cameron, A. D.; Keith, M.; Hobbs, G.; Norris, R. P.; Mao, M. Y.; Middelberg, E.

2011-07-01

Infrared-faint radio sources (IFRS) are objects which are strong at radio wavelengths but undetected in sensitive Spitzer observations at infrared wavelengths. Their nature is uncertain and most have not yet been associated with any known astrophysical object. One possibility is that they are radio pulsars. To test this hypothesis we undertook observations of 16 of these sources with the Parkes Radio Telescope. Our results limit the radio emission to a pulsed flux density of less than 0.21 mJy (assuming a 50 per cent duty cycle). This is well below the flux density of the IFRS. We therefore conclude that these IFRS are not radio pulsars.

Some aspects of UO{sub 2} powder production

Energy Technology Data Exchange (ETDEWEB)

Balakrishna, P; Asnani, C K; Prabhakar Rao, L; Kartha, R M; Pillai, P K.M. [Nuclear Fuel Complex, Hyderabad (India)

1994-06-01

UO{sub 2} powder is being produced in a chemical plant from enriched UF{sub 6} and supplied to the pelletizing plant. Small quantities of scrap UO{sub 2} received back from the pelletizing plant are also recycled in the chemical plant to produce UO{sub 2} powder. The powder should be of a consistently high quality so as to finally yield high density sintered pellets with minimum rejection. The final yield of acceptable finished pellets depends on the quality of the powder in the chemical plant as well as the quality of pressing in the pelletizing plant. In this paper, some examples of measures adopted for achieving good quality powder production are presented. (author). 9 refs., 2 figs.

Introduction to powder metallurgy processes for titanium manufacturing

International Nuclear Information System (INIS)

Esteban, P. G.; Bolzoni, L.; Ruiz-Navas, E. M.; Gordo, E.

2011-01-01

The development of new extraction processes to produce titanium in powder form leads Powder Metallurgy to an advantage position among the manufacturing processes for titanium. The cost reduction of base material, coupled with the economy of the powder metallurgy processes, give titanium industry the chance to diversify its products, which could lead to production volumes able to stabilise the price of the metal. This work reviews some of the Powder Metallurgy techniques for the manufacturing of titanium parts, and describes the two typical approaches for titanium manufacturing: Blending Elemental and Prealloyed Powders. Among others, conventional pressing and sintering are described, which are compared with cold and hot isostatic pressing techniques. Real and potential applications are described. (Author) 71 refs.

Application of gamma irradiation for incorporation of rubber powder in the formulations EPDM and NBR rubber

International Nuclear Information System (INIS)

Kiyan, Ludmila de Ysasa Pozzo

2014-01-01

The natural decomposition of rubber is a very slow process due to its three-dimensional network formed by vulcanized crosslinked structures becoming extremely difficult to reprocess this material. The present work aims to study the application of gamma irradiation as devulcanization process for material reuse/recycling. The interactions of elastomers with ionizing radiation of a gamma source were investigated and the changes in physicochemical properties of the materials were evaluated. Formulations of NBR (acrylonitrile - butadiene) and EPDM (ethylene - propylene - diene terpolymer) from the rubber industry were crosslinked by conventional sulfur-based mixing. Master - batch was processed with rubber powder (industrial waste) and virgin rubber. The raw material (master batch) was irradiated in 60 Co source at doses of 50, 100, 150 kGy and dose rate of 5 kGy h -1 at room temperature. The irradiated material was incorporated in classical sulfur-based formulations. The formulations were characterized by: infrared spectroscopy (FTIR), thermal analysis (TG and DTG), tensile strength, elongation at break, hardness, abrasion resistance, rheometry and swelling. The results showed a predominance of chain scission at a dose of 50 kGy for EPDM rubber. For nitrile predominance of chain scission was observed at a dose of 100 kGy. These results show the possibility of the use of gamma radiation for the reuse/recycling of EPDM and nitrile rubbers. (author)

Infrared and chemical characterization of natural amethysts and prasiolites colored by irradiation

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Fernando Soares Lameiras

2009-09-01

Full Text Available The infrared bands of amethyst and prasiolite samples from different origins were correlated to the trace elements contents. Amethysts have an iron content greater than 20 ppm and a low content of sodium and potassium. Prasiolites have an aluminum content greater than 120 ppm and a higher overall trace elements content, which accounts for a strong absorption between 3200 and 3600 cm-1. Colorless samples of quartz that become amethysts and prasiolites after irradiation have infrared spectra at room temperature with a broad band at 3441 cm-1 and a sharp band at 3595 cm-1. The broad band splits in several bands at low temperatures that are related to AlSi and FeSi. The color of amethysts and prasiolites are assigned to [AlSiO4/h+]º and [FeSiO4/h+]º centers formed by the exposure to ionizing irradiation and to the influence of lattice distortions due to the content of iron as a substitute for silicon and a high content of trace elements of large ionic radius like potassium.

Nonlinear Optical Imaging for Sensitive Detection of Crystals in Bulk Amorphous Powders

OpenAIRE

KESTUR, UMESH S.; WANAPUN, DUANGPORN; TOTH, SCOTT J.; WEGIEL, LINDSAY A.; SIMPSON, GARTH J.; TAYLOR, LYNNE S.

2012-01-01

The primary aim of this study was to evaluate the utility of second-order nonlinear imaging of chiral crystals (SONICC) to quantify crystallinity in drug–polymer blends, including solid dispersions. Second harmonic generation (SHG) can potentially exhibit scaling with crystallinity between linear and quadratic depending on the nature of the source, and thus, it is important to determine the response of pharmaceutical powders. Physical mixtures containing different proportions of crystalline n...

Characterization of powdered fish heads for bone graft biomaterial applications.

Science.gov (United States)

Oteyaka, Mustafa Ozgür; Unal, Hasan Hüseyin; Bilici, Namık; Taşçı, Eda

2013-01-01

The aim of this study was to define the chemical composition, morphology and crystallography of powdered fish heads of the species Argyrosomus regius for bone graft biomaterial applications. Two sizes of powder were prepared by different grinding methods; Powder A (coarse, d50=68.5 µm) and Powder B (fine, d50=19.1 µm). Samples were analyzed using X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), thermogravimetry (TG), and energy dispersive X-ray spectroscopy (EDS). The powder was mainly composed of aragonite (CaCO3) and calcite (CaCO3). The XRD pattern of Powder A and B matched standard aragonite and calcite patterns. In addition, the calcium oxide (CaO) phase was found after the calcination of Powder A. Thermogravimetry analysis confirmed total mass losses of 43.6% and 47.3% in Powders A and B, respectively. The microstructure of Powder A was mainly composed of different sizes and tubular shape, whereas Powder B showed agglomerated particles. The high quantity of CaO and other oxides resemble the chemical composition of bone. In general, the powder can be considered as bone graft after transformation to hydroxyapatite phase.

Compaction of amorphous iron–boron powder

DEFF Research Database (Denmark)

Hendriksen, Peter Vang; Mørup, Steen; Koch, Christian

1993-01-01

Large scale practical use of bulk amorphous alloys requires the capability of molding the material to a desired design, for instance by compaction of an amorphous powder. This is a difficult task because the sintering temperature is limited by the crystallization temperature of the alloy.1 Here we......, should facilitate a compaction. The passivation layer, however, impedes a compaction. Isostatic pressing at 540 K at a pressure of 200 MPa clearly illustrated this; pellets pressed from passivated powder were much more brittle than pellets pressed from unpassivated powder. The density of the pellets...... was very low ([approximately-equal-to]25% of the density of bulk FeB). We have designed a die for uniaxial pressing in which the compaction can be performed without exposing the powder to air and have obtained densities larger than 60% of that of bulk FeB. We have reported studies of the dependence...

Sun drying of residual annatto seed powder

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Dyego da Costa Santos

2015-01-01

Full Text Available Residual annatto seeds are waste from bixin extraction in the food, pharmaceutical and cosmetic industries. Most of this by-product is currently discarded; however, the use of these seeds in human foods through the elaboration of powder added to other commercial powders is seen as a viable option. This study aimed at drying of residual annatto powder, with and without the oil layer derived from the industrial extraction of bixin, fitting different mathematical models to experimental data and calculating the effective moisture diffusivity of the samples. Powder containing oil exhibited the shortest drying time, highest drying rate (≈ 5.0 kg kg-1 min-1 and highest effective diffusivity (6.49 × 10-12 m2 s-1. All mathematical models assessed were a suitable representation of the drying kinetics of powders with and without oil, with R2 above 0.99 and root mean square error values lower than 1.0.

Detection of compatibility between baclofen and excipients with aid of infrared spectroscopy and chemometry.

Science.gov (United States)

Rojek, Barbara; Wesolowski, Marek; Suchacz, Bogdan

2013-12-01

In the paper infrared (IR) spectroscopy and multivariate exploration techniques: principal component analysis (PCA) and cluster analysis (CA) were applied as supportive methods for the detection of physicochemical incompatibilities between baclofen and excipients. In the course of research, the most useful rotational strategy in PCA proved to be varimax normalized, while in CA Ward's hierarchical agglomeration with Euclidean distance measure enabled to yield the most interpretable results. Chemometrical calculations confirmed the suitability of PCA and CA as the auxiliary methods for interpretation of infrared spectra in order to recognize whether compatibilities or incompatibilities between active substance and excipients occur. On the basis of IR spectra and the results of PCA and CA it was possible to demonstrate that the presence of lactose, β-cyclodextrin and meglumine in binary mixtures produce interactions with baclofen. The results were verified using differential scanning calorimetry, differential thermal analysis, thermogravimetry/differential thermogravimetry and X-ray powder diffraction analyses. Copyright © 2013 Elsevier B.V. All rights reserved.

Properties of magnetic nickel/porous-silicon composite powders

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Toshihiro Nakamura

2012-09-01

Full Text Available The magnetic and photoluminescence (PL properties of nickel/porous-silicon (Ni/PSi composite powders are investigated. Ni/PSi composite powders are prepared by stain etching of Si powder in a HF/HNO3 solution followed by electroless plating of Ni nanoparticles on the stain-etched PSi powder in a NiCl2 solution. The Ni/PSi powders exhibit hydrophillicity, superparamagnetism caused by the deposited Ni nanoparticles, and orange-red PL owing to the nanostructured PSi surface. The degree of magnetization decreases with increasing Ni plating time, indicating its dependence on the size of the Ni nanoparticles. The Ni/PSi composite powders also show a stronger magnetization as compared to that of the Ni-particle-plated Si powder. The stronger magnetization results from the larger surface area of PSi. The PL intensity, peak wavelength, and lifetime of Ni/PSi are strongly dependent on the NiCl2 concentration. This dependence is due to the different thickness of the oxide overlayer on the PSi surface formed during the Ni plating process. The existence of the oxide overlayer also results in a small change in the PL intensity against excitation time.

Application of Pre-coated Microfiltration Ceramic Membrane with Powdered Activated Carbon for Natural Organic Matter Removal from Secondary Wastewater Effluent

KAUST Repository

Kurniasari, Novita

2012-12-01

Ceramic membranes offer more advantageous performances than conventional polymeric membranes. However, membrane fouling caused by Natural Organic Matters (NOM) contained in the feed water is still become a major problem for operational efficiency. A new method of ceramic membrane pre-coating with Powdered Activated Carbon (PAC), which allows extremely contact time for adsorbing aquatic contaminants, has been studied as a pre-treatment prior to ceramic microfiltration membrane. This bench scale study evaluated five different types of PAC (SA Super, G 60, KCU 6, KCU 8 and KCU 12,). The results showed that KCU 6 with larger pore size was performed better compared to other PAC when pre-coated on membrane surface. PAC pre-coating on the ceramic membrane with KCU 6 was significantly enhance NOM removal, reduced membrane fouling and improved membrane performance. Increase of total membrane resistance was suppressed to 96%. The removal of NOM components up to 92%, 58% and 56% for biopolymers, humic substances and building blocks, respectively was achieved at pre-coating dose of 30 mg/l. Adsorption was found to be the major removal mechanism of NOM. Results obtained showed that biopolymers removal are potentially correlated with enhanced membrane performance.

Chemical fingerprinting of Arabidopsis using Fourier transform infrared (FT-IR) spectroscopic approaches.