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Sample records for preparation process simpler

  1. Simpler Adaptive Optics using a Single Device for Processing and Control

    Science.gov (United States)

    Zovaro, A.; Bennet, F.; Rye, D.; D'Orgeville, C.; Rigaut, F.; Price, I.; Ritchie, I.; Smith, C.

    The management of low Earth orbit is becoming more urgent as satellite and debris densities climb, in order to avoid a Kessler syndrome. A key part of this management is to precisely measure the orbit of both active satellites and debris. The Research School of Astronomy and Astrophysics at the Australian National University have been developing an adaptive optics (AO) system to image and range orbiting objects. The AO system provides atmospheric correction for imaging and laser ranging, allowing for the detection of smaller angular targets and drastically increasing the number of detectable objects. AO systems are by nature very complex and high cost systems, often costing millions of dollars and taking years to design. It is not unusual for AO systems to comprise multiple servers, digital signal processors (DSP) and field programmable gate arrays (FPGA), with dedicated tasks such as wavefront sensor data processing or wavefront reconstruction. While this multi-platform approach has been necessary in AO systems to date due to computation and latency requirements, this may no longer be the case for those with less demanding processing needs. In recent years, large strides have been made in FPGA and microcontroller technology, with todays devices having clock speeds in excess of 200 MHz whilst using a 1kHz) with low latency (< 1ms) to achieve a good AO correction. As part of the Space Environment Cooperative Research Centre (SERC) this AO system design will be used as a demonstrator for what is possible with ground based AO corrected satellite imaging and ranging systems. The ability to directly and efficiently interface the wavefront sensor and deformable mirror is an important step in reducing the cost and complexity of an AO system. It is hoped that in the future this design can be modified for use in general AO applications, such as in 1-3 m telescopes for space surveillance, or even for amateur astronomy.

  2. Simpler valve for reciprocating engines

    Science.gov (United States)

    Akkerman, J. W.

    1978-01-01

    Simpler design eliminating camshafts, cams, and mechanical springs should improve reliability of hydrazine powered reciprocating engines. Valve is expected to improve efficiency, and reduce weight of engines in range up to 50 horsepower.

  3. Faster and Simpler Minimal Conflicting Set Identification

    CERN Document Server

    Ouangraoua, Aida

    2012-01-01

    Let C be a finite set of N elements and R = r_1,r_2,..., r_m a family of M subsets of C. A subset X of R verifies the Consecutive Ones Property (C1P) if there exists a permutation P of C such that each r_i in X is an interval of P. A Minimal Conflicting Set (MCS) S is a subset of R that does not verify the C1P, but such that any of its proper subsets does. In this paper, we present a new simpler and faster algorithm to decide if a given element r in R belongs to at least one MCS. Our algorithm runs in O(N^2M^2 + NM^7), largely improving the current O(M^6N^5 (M+N)^2 log(M+N)) fastest algorithm of [Blin {\\em et al}, CSR 2011]. The new algorithm is based on an alternative approach considering minimal forbidden induced subgraphs of interval graphs instead of Tucker matrices.

  4. Preparation of silver powder through glycerol process

    Indian Academy of Sciences (India)

    Amit Sinha; B P Sharma

    2005-06-01

    High purity fine silver powder with uniform particle morphology was prepared through glycerol process. The process involves reduction of silver nitrate by glycerol under atmospheric conditions at a temperature below 175°C. Glycerol, in this process, acts as a solvent as well as a reducing agent. The powders prepared through this process were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and chemical analysis. The powders were well crystalline and contained oxygen, carbon and hydrogen as impurities. Overall purity was better than 99.9%. The yield of silver powder was better than 99%.

  5. Process for the preparation of purified inulin

    NARCIS (Netherlands)

    Leeuwen, van M.B.; Slaghek, T.M.; Wit, de D.; Kuzee, H.C.; Raaijmakers, H.W.C.

    1997-01-01

    A process is described for the preparation of oligosaccharides, in particular inulin, which are virtually free from mono- and disaccharides, such as glucose, fructose and sucrose, in that the oligosaccharide is subjected to hydrolysis in the presence of a solid acid catalyst, in particular a strongl

  6. Process for the preparation of aromatic compounds

    NARCIS (Netherlands)

    Schenk, N.J.; Biesbroek, Arnold; Heeres, André; Heeres, Hero

    2015-01-01

    Aromatic compounds are prepared from a feed stream comprising biomass or a mixture of biomass and synthetic polymer in a process, comprising: a) subjecting the feed stream to a pyrolysis treatment in the presence of a cracking catalyst to yield a vaporous fraction comprising hydrocarbons with

  7. Professional Preparation: A Process of Discovery.

    Science.gov (United States)

    Wendt, Janice

    Self awareness is a key element in the effectiveness of teacher performance. To a large extent, however, individual psychology and the growth process have been neglected in the preparation of teachers. Four guidelines can aid prospective teachers to gain strengths they will need in the classroom. The first is increasing student teachers' autonomy…

  8. Process for the preparation of alkyl glycosides

    NARCIS (Netherlands)

    De Goede, A.T.J.; Van der Leij, I.G.; Van der Heijden, A.M.; Van Rantwijk, F.; Van Bekkum, H.

    1996-01-01

    Abstract of WO 9636640 (A2) The present invention relates to a process for the preparation of alkyl glycosides by reacting an alcohol with a saccharide or a lower-alkyl glycoside in the presence of a catalyst, wherein the catalyst is a mesoporous silica-based molecular sieve material. This proce

  9. Process for preparation of MR contrast agents

    DEFF Research Database (Denmark)

    2002-01-01

    The present invention provides a process for the preparation of an MR contrast agent, said process comprising: i) obtaining a solution in a solvent of a hydrogenatable, unsaturated substrate compound and a catalyst for the hydrogenation of said substrate compound; ii) introducing said solution...... in droplet form into a chamber containing hydrogen gas (H2) enriched in para-hydrogen (p-1H2) and/or ortho-deuterium (o-2H2) whereby to hydrogenate said substrate to form a hydrogenated imaging agent; iii) optionally subjecting said hydrogenated imaging agent to a magnetic field having a field strength below...

  10. Dry processing versus dense medium processing for preparing thermal coal

    CSIR Research Space (South Africa)

    De Korte, GJ

    2013-10-01

    Full Text Available in the region. In addition to not requiring water, the technique is less expensive than dense medium processing - both in terms of capital cost and operating cost. An added benefit when preparing coal for use in power stations is the lower moisture content...

  11. Simpler criterion on W state for perfect quantumstate splitting and quantum teleportation

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A simpler criterion is presented to judge whether a W state can be taken as quantum channel forperfectly splitting or teleporting an arbitrary single-qubit state. If the W state is usable,the detailed manipulations in the two quantum information processes are amply shown. Moreover,some relevant discussions are made.

  12. Simpler, faster and shorter labels for distances in graphs

    DEFF Research Database (Denmark)

    Alstrup, Stephen; Gavoille, Cyril; Halvorsen, Esben Bistrup;

    2016-01-01

    -old result, which uses labels of size $(\\log 3)n$ and $\\Oh(n / \\log n)$ decoding time, and Gavoille et al.\\ (SODA'01), which uses labels of size $11n+o(n)$ and $O(\\log\\log n)$ decoding time. In addition, our algorithm is simpler than the previous ones. In the case of integral edge weights of size at most $W...

  13. Simpler Variable-Speed Drive for Fan or Pump

    Science.gov (United States)

    Obler, H. D.

    1982-01-01

    Static pressure developed by a fan or pump is used directly to control its speed in a new drive unit. System is simpler and more economical than many other speed controllers, although it is less accurate and has a narrower speed range. However, since very accurate control is not usually required for fans and pumps, unit would work well in many applications.

  14. Simpler, faster and shorter labels for distances in graphs

    DEFF Research Database (Denmark)

    Alstrup, Stephen; Gavoille, Cyril; Halvorsen, Esben Bistrup

    2016-01-01

    -old result, which uses labels of size $(\\log 3)n$ and $\\Oh(n / \\log n)$ decoding time, and Gavoille et al.\\ (SODA'01), which uses labels of size $11n+o(n)$ and $O(\\log\\log n)$ decoding time. In addition, our algorithm is simpler than the previous ones. In the case of integral edge weights of size at most $W...

  15. Process for the preparation of calcium superoxide

    Science.gov (United States)

    Ballou, E. V.; Wood, P. C.; Wydeven, T. J.; Spitze, L. A. (Inventor)

    1978-01-01

    Calcium superoxide is prepared in high yields by spreading a quantity of calcium peroxide diperoxyhydrate on the surface of a container, positioning said container in a vacuum chamber on a support structure through which a coolant fluid can be circulated, partially evacuating said vacuum chamber, allowing the temperature of the diperoxyhydrate to reach the range of about 0 to about 40 C; maintaining the temperature selected for a period of time sufficient to complete the disproproriation of the diperoxyhydrate to calcium superoxide, calcium hydroxide, oxygen, and water; constantly and systematically removing the water as it is formed by sweeping the reacting material with a current of dry inert gas and/or by condensation of said water on a cold surface; backfilling the chamber with a dry inert gas; and finally, recovering the calcium superoxide produced.

  16. Data Preparation Process for the Buildings Performance Database

    Energy Technology Data Exchange (ETDEWEB)

    Walter, Travis; Dunn, Laurel; Mercado, Andrea; Brown, Richard E.; Mathew, Paul

    2014-06-30

    The Buildings Performance Database (BPD) includes empirically measured data from a variety of data sources with varying degrees of data quality and data availability. The purpose of the data preparation process is to maintain data quality within the database and to ensure that all database entries have sufficient data for meaningful analysis and for the database API. Data preparation is a systematic process of mapping data into the Building Energy Data Exchange Specification (BEDES), cleansing data using a set of criteria and rules of thumb, and deriving values such as energy totals and dominant asset types. The data preparation process takes the most amount of effort and time therefore most of the cleansing process has been automated. The process also needs to adapt as more data is contributed to the BPD and as building technologies over time. The data preparation process is an essential step between data contributed by providers and data published to the public in the BPD.

  17. Preparing Health Care Processes for IT Integration

    DEFF Research Database (Denmark)

    Walley, Paul; Laursen, Martin Lindgård

    2005-01-01

    Many health care supply chains are now attempting to achieve greater IT integration, between primary and secondary care, as well as internal integration within hospital systems. Conventional theory suggests that these types of initiative should coincide with extensive process reengineering...... effectiveness and efficiency of the system. Using data from two countries and involving 200 hospitals, the paper addresses the current state of determinacy of processes and explores the potential route towards standardisation. We hypothesise that management paradigms such as “lean thinking...

  18. Preparing Health Care Processes for IT Integration

    DEFF Research Database (Denmark)

    Walley, Paul; Laursen, Martin Lindgård

    2005-01-01

    effectiveness and efficiency of the system. Using data from two countries and involving 200 hospitals, the paper addresses the current state of determinacy of processes and explores the potential route towards standardisation. We hypothesise that management paradigms such as “lean thinking...

  19. A rigorous and simpler method of image charges

    Science.gov (United States)

    Ladera, C. L.; Donoso, G.

    2016-07-01

    The method of image charges relies on the proven uniqueness of the solution of the Laplace differential equation for an electrostatic potential which satisfies some specified boundary conditions. Granted by that uniqueness, the method of images is rightly described as nothing but shrewdly guessing which and where image charges are to be placed to solve the given electrostatics problem. Here we present an alternative image charges method that is based not on guessing but on rigorous and simpler theoretical grounds, namely the constant potential inside any conductor and the application of powerful geometric symmetries. The aforementioned required uniqueness and, more importantly, guessing are therefore both altogether dispensed with. Our two new theoretical fundaments also allow the image charges method to be introduced in earlier physics courses for engineering and sciences students, instead of its present and usual introduction in electromagnetic theory courses that demand familiarity with the Laplace differential equation and its boundary conditions.

  20. New simpler method of matching NLO corrections with parton shower Monte Carlo

    CERN Document Server

    Jadach, S; Sapeta, S; Siodmok, A; Skrzypek, M

    2016-01-01

    Next steps in development of the KrkNLO method of implementing NLO QCD corrections to hard processes in parton shower Monte Carlo programs are presented. This new method is a simpler alternative to other well-known approaches, such as MC@NLO and POWHEG. The KrkNLO method owns its simplicity to the use of parton distribution functions (PDFs) in a new, so-called Monte Carlo (MC), factorization scheme which was recently fully defined for the first time. Preliminary numerical results for the Higgs-boson production process are also presented.

  1. Preparing Process of Cerium Acetate and Rare Earth Acetate

    Institute of Scientific and Technical Information of China (English)

    Qiao Jun; Ma Ying; Xu Yanhui; Zhang Jun; Chang Shu; Hao Xianku

    2004-01-01

    Preparing process was presented and the influences of concentration of acetic acid, reaction temperature, the ratio of cerium carbonate and acetic acid, heat preservation time to the yield of cerium acetate were discussed.The crystalline cerium acetate and rare earth acetate such as ( La, Ce, Pr, Nd) (Ac) 3, ( Ce, Pr, Nd) (Ac) 3, ( Pr, Nd, Er,Y) (Ac) 3 and yttrium acetate were prepared under this condition.The shape, structure and composition of the crystals were determined by the methods of SEM, TG-DTA, X-ray diffraction and chemical analysis.The optimum prepared conditions of cerium acetate were described.This prepared process has characteristics such as simple process route, low cost, high yield, good quality, no pollution to environment, etc.

  2. The Kinetic Stabilizer: A Route to Simpler Tandem Mirror Systems?

    Energy Technology Data Exchange (ETDEWEB)

    Post, R

    2001-05-30

    This paper discusses a new approach to an MHD stabilizing technique for magnetic fusion systems of the axisymmetric ''open-ended'' variety. The concept is adaptable to tandem-mirror systems and would result in a major simplification of such systems, accompanied by a substantial improvement in their confinement characteristics, The paper first discusses the present impetus to find a simpler and less expensive route to fusion than that offered by the mainline approach, the tokamak. The history of magnetic fusion research shows that closed and open systems exhibit very different confinement characteristics. Closed systems, such as the tokamak, the stellarator, or the reversed-field pinch have cross-field transport that is dominated by plasma turbulence. By contrast, there are examples of open-systems where turbulence, if present at all, was at such low levels that the transport agreed with ''classical'' predictions. The clearest examples are ones in which the field geometry was axiymmetric. However axisymmetric mirror systems are subject to MHD instability. Thus in the years following the famous Ioffe experiment, most open systems have employed asymmetric magnetic fields, with attendant problems of complexity and enhanced cross-field transport. This paper proposes a new means of stabilizing axisymmetric mirror-based systems. The idea, called the ''Kinetic Stabilizer'' has roots in experiments performed with the axisymmetric Gas Dynamic Trap at Novosibirsk. In these experiments, performed in a high collisionality plasma regime, it was shown that the presence of the effluent plasma in the positive-curvature expanding-field region outside the mirrors was effective in stabilizing a high-beta (30 percent) confined plasma against MHD modes. In the plasmas of tandem-mirror systems the density of the effluent plasma is too low to employ this method of stabilization. The Kinetic Stabilizer solves this problem by using

  3. Simpler spectrophotometric assay of paracetamol in tablets and urine samples

    Science.gov (United States)

    Sirajuddin; Khaskheli, Abdul Rauf; Shah, Afzal; Bhanger, Muhammad Iqbal; Niaz, Abdul; Mahesar, Sarfaraz

    2007-11-01

    A very fast, economical and simpler direct spectrophotometric method was investigated for paracetamol (PC) determination in aqueous medium without using any chemical reagents. The method is based on the photo-absorption of the analyte at 243 nm after dissolution in water. The change in structure of PC after addition of water was studied by comparing the corresponding FTIR spectra. Optimization studies were conducted by using a 5 μg ml -1 standard solution of the analyte. Various parameters studied include, time for stability and measurement of spectra, effect of HCl, NaOH, CH 3COOH and NH 3 for change in absorbance and shift in spectra, interference by some analgesic drugs and some polar solvents and temperature effect. After optimization, Beer's law was obeyed in the range of 0.3-20 μg ml -1 PC solution with a correlation coefficient of 0.9999 and detection limit of 0.1 μg ml -1. The newly developed method was successfully applied for PC determination in some locally available tablets and urine samples. The proposed method is very useful for quick analysis of various types of solid and liquid samples containing PC.

  4. Simpler and More Accurate: Weighing the Mercury in Electrolytic Cells by Radiotracer Dilution Method

    Directory of Open Access Journals (Sweden)

    Sugiharto

    2010-08-01

    Full Text Available Weight of mercury in electrolytic cell of soda industry is usually measured gravimetrically, which is typical labor work in character. Error sources of the gravimetric method might have come from the fact that some mercury’s are usually trapped in the cell due to complicated structure of electrolytic cell. This cause unknown errors. In addition, formation of amalgam at the cathode may cause a further uncertainty in the measurement. Total error from gravimetric method is 4% on average. Radiotracer dilution method provides advantages either for simplification of procedure and reduction of measurement error. In this experiment radioisotope mercury 203Hg, which was prepared in nuclear reactor was used to examine 13 of 14 electrolytic cells of soda plant. Each electrolytic cell was designed containing approximately 700 kg inactive mercury. Before injection, the radioisotope mercury was mixed with non radioisotope mercury in a bath to obtain a suitable injection aliquots and standard references. Calibration curve, which was derived from two stage dilution processes taken from standard references, was used to examine degree of mixing between radioisotope and non radioisotope mercury and it was also used in weight calculation of non radioisotope mercury in electrolytic cell. Injection was carried out simply by pouring the injection aliquots into the flowing mercury at the inlet side of the cell. Mercury samples from the cells were extracted at regular time intervals and filled into vials for counting. This was done for the primary conformation of the completeness of mixing of the tracer with the non radioisotope mercury in each cell. When complete mixing is achieved, the unknown quantity of mercury in each cell was calculated based on mass balance principle. From the calculation the weight of mercury in each electrolytic cell was not the same and maximum error of measurement obtained from this method is 2.48 %. Compared to gravimetrically error

  5. Thermo-analysis of Preparation Process for Electron Trapping Materials

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The heated process of raw materials for electron trapping materials (ETM) is investigated by thermo-analysis method. The temperature ranges of raw materials experienced some physical and chemical change processes, such as dehydration, organic solvent removal, crystal sulphur burning, oxidation of alkaline earth sulfides and solid phase reaction (rare earth doped) and so on, are obtained. The experimental results also show that the presence of trace oxygen in shielded gas is very harmful to prepare the ETM.The raw material thermo-analysis results provide very important experimental reference for optimizing the ETM preparation techniques.

  6. Preparation of Nano/Micron Composite Materials by Process Method

    Institute of Scientific and Technical Information of China (English)

    GAN Ai-feng; WEI Qi; JI; Yuan; HU Chuan-xin; YAO Jun-min

    2004-01-01

    This thesis put forward a method that controls the process of synthesizing nanomaterial to realize the composite of nanomaterial and micronmaterial. This thesis realizes the composite of nanomaterial and micronmaterial by adding micronmaterial during production of nanomaterial through sol-gel method, also introduces the technique and experiment's process preparation of nanocomposite material, and successfully prepared nanocomposite materials with nano-PbTiO3 covered on the surface of micron-Ni. According to the sample's SEM-pictures, the core-shell can be observed plate microstructure, and it is uniform, tight, full and good.

  7. Daimler process audit preparation, execution and evaluation in Faurecia Kosice

    Directory of Open Access Journals (Sweden)

    Ľubomír Lengyel

    2011-04-01

    Full Text Available This paper is describing process of preparation to successful passing of Daimler Process Audit. From process point of view VDA 6.3 standard has been the base accompanied with Daimler additions, driven by internal Faurecia Audit standard. Continual improvement process based on Deming’s cycle has been applied. The paper is intended for all professionals who are concerned with the process and product quality improvement and quality audit in the organization. The paper has been compiled in connection with resolving project KEGA 3/6411/08 Transformation of the already existing study programme Management of production quality to an university-wide bilingual study programme.

  8. QUALITY IMPROVEMENT MODEL AT THE MANUFACTURING PROCESS PREPARATION LEVEL

    Directory of Open Access Journals (Sweden)

    Dusko Pavletic

    2009-12-01

    Full Text Available The paper expresses base for an operational quality improvement model at the manufacturing process preparation level. A numerous appropriate related quality assurance and improvement methods and tools are identified. Main manufacturing process principles are investigated in order to scrutinize one general model of manufacturing process and to define a manufacturing process preparation level. Development and introduction of the operational quality improvement model is based on a research conducted and results of methods and tools application possibilities in real manufacturing processes shipbuilding and automotive industry. Basic model structure is described and presented by appropriate general algorithm. Operational quality improvement model developed lays down main guidelines for practical and systematic application of quality improvements methods and tools.

  9. [Study on preparation process of artesunate polylactic acid microspheres].

    Science.gov (United States)

    Pan, Xu-Wang; Wang, Wei; Fang, Hong-Ying; Wang, Fu-Gen; Cai, Zhao-Bin

    2013-12-01

    This study aims to investigate the preparation process and in vitro release behavior of artesunate polylactic acid microspheres, in order to prepare an artesunate polylactic acid (PLA) administration method suitable for hepatic arterial embolization. With PLA as the material and polyvinyl alcohol (PVA) as the emulsifier, O/W emulsion/solvent evaporation method was adopted to prepare artesunate polylactic acid microspheres, and optimize the preparation process. With drug loading capacity, encapsulation efficiency and particle size as indexes, a single factor analysis was made on PLA concentration, PVA concentration, drug loading ratio and stirring velocity. Through an orthogonal experiment, the optimal processing conditions were determined as follows: PLA concentration was 9. 0% , PVA concentration was 0. 9% , drug loading ratio was 1:2 and stirring velocity was 1 000 r x min(-1). According to the verification of the optimal process, microsphere size, drug loading and entrapment rate of artesunate polylactic acid microspheres were (101.7 +/- 0.37) microm, (30.8 +/- 0.84)%, (53.6 +/- 0.62)%, respectively. The results showed that the optimal process was so reasonable and stable that it could lay foundation for further studies.

  10. INFORMATION SYSTEM OF AUTOMATION OF PREPARATION EDUCATIONAL PROCESS DOCUMENTS

    Directory of Open Access Journals (Sweden)

    V. A. Matyushenko

    2016-01-01

    Full Text Available Information technology is rapidly conquering the world, permeating all spheres of human activity. Education is not an exception. An important direction of information of education is the development of university management systems. Modern information systems improve and facilitate the management of all types of activities of the institution. The purpose of this paper is development of system, which allows automating process of formation of accounting documents. The article describes the problem of preparation of the educational process documents. Decided to project and create the information system in Microsoft Access environment. The result is four types of reports obtained by using the developed system. The use of this system now allows you to automate the process and reduce the effort required to prepare accounting documents. All reports was implement in Microsoft Excel software product and can be used for further analysis and processing.

  11. Preparing School Psychologists to Testify at Due Process Hearings.

    Science.gov (United States)

    Fineman, Carol A.

    Guidelines are presented for school psychologists in order to make their testimony at special education due process hearings as effective as possible. Recommendations are offered to prepare the school psychologist to: (1) accept the role of expert witness; (2) organize and review case materials; (3) state relevant rules, procedures, and criteria;…

  12. Career Preparation: A Longitudinal, Process-Oriented Examination

    Science.gov (United States)

    Stringer, Kate; Jennifer Kerpelman; Vladimir Skorikov

    2011-01-01

    Preparing for an adult career through careful planning, choosing a career, and gaining confidence to achieve career goals is a primary task during adolescence and early adulthood. The current study bridged identity process literature and career construction theory (Savickas, 2005) by examining the commitment component of career adaptability,…

  13. Futurism: A Needed Process in School Personnel Preparation.

    Science.gov (United States)

    Burdin, Joel L.

    This paper projects present trends and capabilities into the future, conjectures about the educational implications of these trends, and proposes some possible responses for those involved in the preparation of school personnel. It is simultaneously an illustration and an application of the process of "futurism" and its increasing relevance to…

  14. [The modified process for preparing natural organic polymer flocculant chitosan].

    Science.gov (United States)

    Zeng, D; Yu, G; Zhang, P; Feng, Z

    2001-05-01

    The modified process for preparing chitosan from crab or lobster shells was developed. In the decalcification stage, 10% HCl was used as soaking solution with addition of a small quantity of A as a promoter, and the mass ratio of reactants was 10% HCl:A:crab or lobster shells = 3.5:0.5:1, continuously stirring the crab or lobster shells at 30 degrees C for 3 h in place of simply soaking the crab or lobster shells at room temperature for 16-24 h in the previous process. In the deacetylation stage, 40% NaOH solution was used with addition of a small quantity of B as a promoter, and the mass ratio of reactants was 40% NaOH:B:chitin = 4:0.2:1, keeping reaction at 105 degrees C for 2 h in place of at 115 degrees C for 6 h in the previous process. By this new process, the cost of the raw materials used for preparing chitosan was cut down 49%, the preparation time was shortened by one half, and the main properties of this chitosan such as viscosity, deacetylation and molecular weight all approached or exceeded those of the Sigma' commercial chitosan (Chitosan C-3646).

  15. Increase of entropy in the thermalization of two blocks: a simpler proof

    Science.gov (United States)

    Lima, F. M. S.

    2015-11-01

    The thermalization of two blocks with distinct initial temperatures put inside an insulated recipient is an irreversible process to which the entropic version of the second law of thermodynamics applies, so the entropy of this system must increase. In a very recent note in this journal, Mungan (2015 Eur. J. Phys. 36 048004) has presented a proof of such an increase in the more general case of distinct blocks, but his approach involves the analysis of some series expansions, which sounds mathematically complex for first year undergraduates. His approach also has the disadvantage of demanding the analysis of distinct cases, according to the values of the initial temperatures and thermal capacities of the blocks. In this short note, I make use of the concavity of the logarithm function to present a simpler, elementary proof which is more suitable for introductory physics classes.

  16. Nano-structured polymer composites and process for preparing same

    Science.gov (United States)

    Hillmyer, Marc; Chen, Liang

    2013-04-16

    A process for preparing a polymer composite that includes reacting (a) a multi-functional monomer and (b) a block copolymer comprising (i) a first block and (ii) a second block that includes a functional group capable of reacting with the multi-functional monomer, to form a crosslinked, nano-structured, bi-continuous composite. The composite includes a continuous matrix phase and a second continuous phase comprising the first block of the block copolymer.

  17. Processes for preparing carbon fibers using gaseous sulfur trioxide

    Energy Technology Data Exchange (ETDEWEB)

    Barton, Bryan E.; Lysenko, Zenon; Bernius, Mark T.; Hukkanen, Eric J.

    2016-01-05

    Disclosed herein are processes for preparing carbonized polymers, such as carbon fibers, comprising: sulfonating a polymer with a sulfonating agent that comprises SO.sub.3 gas to form a sulfonated polymer; treating the sulfonated polymer with a heated solvent, wherein the temperature of said solvent is at least 95.degree. C.; and carbonizing the resulting product by heating it to a temperature of 500-3000.degree. C.

  18. Mask process matching using a model based data preparation solution

    Science.gov (United States)

    Dillon, Brian; Saib, Mohamed; Figueiro, Thiago; Petroni, Paolo; Progler, Chris; Schiavone, Patrick

    2015-10-01

    Process matching is the ability to precisely reproduce the signature of a given fabrication process while using a different one. A process signature is typically described as systematic CD variation driven by feature geometry as a function of feature size, local density or distance to neighboring structures. The interest of performing process matching is usually to address differences in the mask fabrication process without altering the signature of the mask, which is already validated by OPC models and already used in production. The need for such process matching typically arises from the expansion of the production capacity within the same or different mask fabrication facilities, from the introduction of new, perhaps more advanced, equipment to deliver same process of record masks and/or from the re-alignment of processes which have altered over time. For state-of-the-art logic and memory mask processes, such matching requirements can be well below 2nm and are expected to reduce below 1nm in near future. In this paper, a data preparation solution for process matching is presented and discussed. Instead of adapting the physical process itself, a calibrated model is used to modify the data to be exposed by the source process in order to induce the results to match the one obtained while running the target process. This strategy consists in using the differences among measurements from the source and target processes, in the calibration of a single differential model. In this approach, no information other than the metrology results is required from either process. Experimental results were obtained by matching two different processes at Photronics. The standard deviation between both processes was of 2.4nm. After applying the process matching technique, the average absolute difference between the processes was reduced to 1.0nm with a standard deviation of 1.3nm. The methods used to achieve the result will be described along with implementation considerations, to

  19. Preparation of polypropylene thermoplastic container via thermoforming process

    Science.gov (United States)

    Ruqiyah Nik Hassan, Nik; Amira Mohd Ghazali, Farah; Aziz Jaafar, Abdul; Mazni Ismail, Noor

    2016-02-01

    In this study, plastic containers made of polypropylene (PP) sheets were fabricated via vacuum thermoforming. Thermoforming is a process used in fabricating plastic parts by changing flat thermoplastic sheet to three dimensional shapes. In preparing these thermoplastic containers, the design and fabrication of mould were first done by using Catia V5 software and CNC milling machine, respectively. The thermoforming process was then performed at various temperatures ranging from 160°C until 200°C on the PP sheet to form the container. From the experiment, it can be suggested that the outcomes of final thermoplastic containers are significantly depends on temperature control during thermoforming process and also the vent holes design of the mould.

  20. A single stage process for the preparation of cycotetramethylene tetranitrmine

    Directory of Open Access Journals (Sweden)

    H. K. Acharya

    1964-10-01

    Full Text Available A single stage process for the preparation of cyclotetrmethlene tetranitramine (HMXhas been developed. The ingredients (i Hexamine in glacial acetic acid, (ii Ammonium nitrate in nitric acid and (iiiacetic anhydride were simultaneously added to glacial acetic acid medium maintained at 45-48 with stirring. The crude yield of the product per 100 gm. of hexamine used is 120 gm having the melting point 265-266C. Purified from acetone the substance melts at 272-275 and passes standard vacuum stability and impact sensitivity tests.

  1. Smooth germanium nanowires prepared by a hydrothermal deposition process

    Energy Technology Data Exchange (ETDEWEB)

    Pei, L.Z., E-mail: lzpei1977@163.com [School of Materials Science and Engineering, Institute of Molecular Engineering and Applied Chemistry, Key Laboratory of Materials Science and Processing of Anhui Province, Anhui University of Technology, Ma' anshan, Anhui 243002 (China); Zhao, H.S. [School of Materials Science and Engineering, Institute of Molecular Engineering and Applied Chemistry, Key Laboratory of Materials Science and Processing of Anhui Province, Anhui University of Technology, Ma' anshan, Anhui 243002 (China); Tan, W. [Henkel Huawei Electronics Co. Ltd., Lian' yungang, Jiangsu 222006 (China); Yu, H.Y. [School of Materials Science and Engineering, Institute of Molecular Engineering and Applied Chemistry, Key Laboratory of Materials Science and Processing of Anhui Province, Anhui University of Technology, Ma' anshan, Anhui 243002 (China); Chen, Y.W. [Department of Materials Science, Fudan University, Shanghai 200433 (China); Fan, C.G. [School of Materials Science and Engineering, Institute of Molecular Engineering and Applied Chemistry, Key Laboratory of Materials Science and Processing of Anhui Province, Anhui University of Technology, Ma' anshan, Anhui 243002 (China); Zhang, Qian-Feng, E-mail: zhangqf@ahut.edu.cn [School of Materials Science and Engineering, Institute of Molecular Engineering and Applied Chemistry, Key Laboratory of Materials Science and Processing of Anhui Province, Anhui University of Technology, Ma' anshan, Anhui 243002 (China)

    2009-11-15

    Smooth germanium nanowires were prepared using Ge and GeO{sub 2} as the starting materials and Cu sheet as the substrate by a simple hydrothermal deposition process. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) characterizations show that the germanium nanowires are smooth and straight with uniform diameter of about 150 nm in average and tens of micrometers in length. X-ray diffraction (XRD) and Raman spectrum of the germanium nanowires display that the germanium nanowires are mainly composed of cubic diamond phase. PL spectrum shows a strong blue light emission at 441 nm. The growth mechanism is also discussed.

  2. An Efficient Chemoenzymatic Process for Preparation of Ribavirin

    Directory of Open Access Journals (Sweden)

    Vladimir Sakharov

    2015-01-01

    Full Text Available Ribavirin is an important antiviral drug, which is used for treatment of many diseases. The pilot-scale chemoenzymatic process for synthesis of the active pharmaceutical ingredient Ribavirin was developed with 32% overall yield and more than 99.5% purity. The described method includes the chemical synthesis of 1,2,4-triazole-3-carboxamide, which is a key intermediate and enzyme-catalyzed transglycosylation reaction for preparation of the desired product. 1,2,4-Triazole-3-carboxamide was synthesized from 5-amino-1,2,4-triazole-3-carboxylic acid by classical Chipen-Grinshtein method. Isolated from E. сoli BL21(DE3/pERPUPHHO1 strain the purine nucleoside phosphorylase was used as a biocatalytical system. All steps of this process were optimized and scaled.

  3. Metathesis process for preparing an alpha, omega-functionalized olefin

    Energy Technology Data Exchange (ETDEWEB)

    Burdett, Kenneth A. (Midland, MI); Mokhtarzadeh, Morteza (Charleston, WV); Timmers, Francis J. (Midland, MI)

    2010-10-12

    A cross-metathesis process for preparing an .alpha.,.omega.-functionalized olefin, such as methyl 9-decenoate, and an .alpha.-olefin having three or more carbon atoms, such as 1-decene. The process involves contacting in a first reaction zone an .alpha.-functionalized internal olefin, such as methyl oleate, and an .alpha.-olefinic monomer having three or more carbon atoms, such as 1-decene, with a first metathesis catalyst to prepare an effluent stream containing the .alpha.,.omega.-functionalized olefin, such as methyl 9-decenoate, an unfunctionalized internal olefin, such as 9-octadecene, unconverted reactant olefins, and optionally, an .alpha.,.omega.-difunctionalized internal olefinic dimer, such as dimethyl 9-octadecen-1,18-dioate; separating said effluent streams; then contacting in a second reaction zone the unfunctionalized internal olefin with ethylene in the presence of a second metathesis catalyst to obtain a second product effluent containing the .alpha.-olefinic monomer having three or more carbon atoms; and cycling a portion of the .alpha.-olefinic monomer stream(s) to the first zone.

  4. Preparation of porcelain tile granulates by more environmentally sustainable processes

    Energy Technology Data Exchange (ETDEWEB)

    Gil, C.; Silvestre, D.; Piquer, J.; Garcia-Ten, J.; Quereda, E.; Vicente, M. J.

    2012-07-01

    This study examines the feasibility of manufacturing glazed porcelain tiles with a more environmentally friendly manufacturing process, by reducing water and thermal energy consumption. The process studied in this paper is dry milling in a pendulum mill, with subsequent granulation (in order to obtain a press powder with similar flow ability to that of spray dried powders). The different morphology of the new granulate with respect to the standard spray-dried granulate modifies the microstructure of the green compacts and thus, their behaviour and fired tile properties. In order to obtain porcelain tiles with the required properties (water absorption, mechanical strength,) changes have been made in the raw materials mixture and in the processing variables. Finally, porcelain tiles measuring 50x50 cm have been manufactured at industrial scale with the new granulate using a conventional firing cycle, obtaining quality levels identical to those provided by the spray-dried granulate. These results open the possibility of preparing porcelain tile body compositions through a manufacturing process alternative to the standard one, more environmentally friendly and with lower costs. (Author)

  5. As Simple as Possible, But No Simpler: A Gentle Introduction to Simulation Modeling

    Science.gov (United States)

    2006-12-01

    SIMPLE AS POSSIBLE, BUT NO SIMPLER: A GENTLE INTRODUCTION TO SIMULATION MODELING Paul J. Sánchez Operations Research Department Naval Postgraduate...Simple as Possible, But No Simpler: A Gentle Introduction to Simulation Modeling 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...to mess things up. Simulation modeling involves a longer chain of inference than does analytical modeling, which is why we generally would prefer to

  6. JADOPPT: java based AutoDock preparing and processing tool.

    Science.gov (United States)

    García-Pérez, Carlos; Peláez, Rafael; Therón, Roberto; Luis López-Pérez, José

    2017-02-15

    AutoDock is a very popular software package for docking and virtual screening. However, currently it is hard work to visualize more than one result from the virtual screening at a time. To overcome this limitation we have designed JADOPPT, a tool for automatically preparing and processing multiple ligand-protein docked poses obtained from AutoDock. It allows the simultaneous visual assessment and comparison of multiple poses through clustering methods. Moreover, it permits the representation of reference ligands with known binding modes, binding site residues, highly scoring regions for the ligand, and the calculated binding energy of the best ranked results. JADOPPT, supplementary material (Case Studies 1 and 2) and video tutorials are available at http://visualanalytics.land/cgarcia/JADOPPT.html. carlosgarcia@usal.es or pelaez@usal.es. Supplementary data are available at Bioinformatics online.

  7. Improving the process of preparing waste water at Kamennolozhskiy UPPN

    Energy Technology Data Exchange (ETDEWEB)

    Abashev, R.G.

    1982-01-01

    The main reasons are examined for low efficient operation of treatment works at the Kamennolozhskiy UPPN and efficient ways to improve quality of waste water by introducing separate collection and preparation of individual types of water, organization of preliminary discharge at the main structures and pinpointing the duration of settling. The process of settling was studied on waste water under field conditions using sampling from a strictly defined level of the settling tank in definite time intervals and analysis of samples for the content of mechanical admixtures and petroleum products. The duration of settling in the reservoir was corrected according to the curve for the dependence of the contaminant content in the waste water on the duration of settling. It was indicated that introduction of recommendations guarantees quality of water of the required condition for injection into productive beds to maintain bed pressure.

  8. Perovskite/polymer solar cells prepared using solution process

    Science.gov (United States)

    Rosa, E. S.; Shobih; Nursam, N. M.; Saputri, D. G.

    2016-11-01

    We report a simple solution-based process to fabricate a perovskite/polymer tandem solar cell using inorganic CH3NH3PM3 as an absorber and organic PCBM (6,6 phenyl C61- butyric acid methyl ester) as an electron transport layer. The absorber solution was prepared by mixing the CH3NH3I (methyl ammonium iodide) with PbI2 (lead iodide) in DMF (N,N- dimethyl formamide) solvent. The absorber and electron transport layer were deposited by spin coating method. The electrical characteristics generated from the cell under 50 mW/cm2 at 25 °C comprised of an open circuit voltage of 0.31 V, a short circuit current density of 2.53 mA/cm2, and a power conversion efficiency of 0.42%.

  9. Preparation of Articular Cartilage Specimens for Scanning Electron Microscopy.

    Science.gov (United States)

    Stupina, T A

    2016-08-01

    We developed and adapted a technology for preparation of articular cartilage specimens for scanning electron microscopy. The method includes prefixation processing, fixation, washing, and dehydration of articular cartilage specimens with subsequent treatment in camphene and air-drying. The technological result consists in prevention of deformation of the articular cartilage structures. The method is simpler and cheaper than the known technologies.

  10. [Chemical and nutritional changes during preparation of whole corn tortillas prepared with instant flour obtained by extrusion process].

    Science.gov (United States)

    Gómez Aldapa, C A; Martínez Bustos, F; Figueroa Cárdenas, J D; Ordorica Falomir, C A; González Hernández, J

    1996-12-01

    Chemical changes of some nutritional components (protein, total dietary fiber, vitamins, lysine, tryptophan, ether extract and fatty acids) of tortillas made from instant whole corn flour prepared by extrusion process (CINVESTAV process) were evaluated. The tortillas prepared by extrusion process were compared with tortillas made by traditional process and raw corn. The protein content of tortillas from both processes were statistically similar to those of the raw corn, although the traditional tortillas showed the lowest actual values. Tortillas from traditional process contained the lowest amount of total dietary fiber and available lysine. The loss of protein, crude fiber, total dietary fiber, available lysine, tryptophan, and vitamin contents during traditional tortillas process, was attributable to the partial loss of pericarp, aleurone and germ tissue during the process. Tortillas prepared by both processes showed loss of vitamins. The thermal treatment in both processes (traditional and extrusion) decreased the ether extract and fatty acids contents. Tortillas prepared by extrusion process showed better nutritional characteristics than traditional tortillas prepared by nixtamalization process.

  11. Novel foaming agent used in preparation process of aluminum foams

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The performances of a novel foaming agent used in the preparation process of aluminum foams were investigated,and the effects of some factors,such as addition of the foaming agent,foaming temperature on the porosity,and appearance of aluminum foams were also discussed.Experimental results show that the novel foaming agent has a wide decomposition temperature range and a mild decomposed rate; the foaming agent has the ability to enhance the viscosity of aluminum melt,as a result,an extra viscosifier such as Ca or SiCp is unnecessary while using this foaming agent; the bubble-free zone in material decreases and the foaming efficiency increases with the increase of foaming agent; the bubble-free zone disappears and the foaming efficiency is near 100% when the addition of foaming agent is more than 1.4wt% ; the porosity of the aluminum foam increases with the increase of foaming agent when the addition of foaming agent is less than 2.2wt% .

  12. Gelation of charged catanionic vesicles prepared by a semispontaneous process.

    Science.gov (United States)

    Huang, Zheng-Lin; Hong, Jhen-Yi; Chang, Chien-Hsiang; Yang, Yu-Min

    2010-02-16

    Various stable charged catanionic vesicles with mean zeta-potential values from +59 mV to -96 mV were successfully prepared from an ion-pair amphiphile (dodecyltrimethylammonium-dodecylsulfate, DTMA-DS) and different amounts of the component ionic surfactants (dodecyltrimethylammonium bromide and sodium dodecyl sulfate) by using a simple semispontaneous process with the aid of cosolvent (1-propanol) addition in water. With the ensuring positively and negatively charged catanionic vesicles, gelation of them by four water-soluble polymers with various charge and hydrophobic characteristics was systematically studied by the tube inversion and rheological characteristic analyses. Four phase maps, which show regions of phase separation, viscous solution, and gel by varying the vesicle composition and polymer content, were thereby constructed. Furthermore, the experimental results of the relaxation time and the storage modulus at 1 Hz for the viscous solutions and gel samples revealed that the interactions at play between charged catanionic vesicles and the water-soluble polymers are of electrostatic and hydrophobic origin. The phase maps and the rheological properties obtained for mixtures of charged catanionic vesicles and polymers may provide useful information for the potential application of catanionic vesicles in mucosal or transdermal delivery of drugs.

  13. Extractive process for preparing high purity magnesium chloride hexahydrate

    Directory of Open Access Journals (Sweden)

    Fezei Radouanne

    2012-01-01

    Full Text Available This paper refers a method for the preparation of magnesium chloride hexahydrate (bischofite from Sebkha el Melah of Zarzis Tunisian natural brine. It is a five-stage process essentially based on crystallization by isothermal evaporation and chemical precipitation. The two first steps were dedicated to the crystallization of sodium chloride and potassiummagnesium double salts, respectively. Then, the resulting liquor was desulfated using calcium chloride solution. After that another isothermal evaporation stage was implemented in order to eliminate potassium ions in the form of carnallite, KCl.MgCl2.6H2O. At the end of this step, the recovered solution primarily composed of magnesium and chloride ions was treated by dioxan in order to precipitate magnesium chloride as MgCl2.6H2O.C4H8O2. This compound dried at constant temperature of 100°C gave good quality magnesium chloride hexahydrate. Besides this salt, the various by-products obtained from the different treatment stages are also useful.

  14. Action preparation shapes processing in early visual cortex.

    Science.gov (United States)

    Gutteling, Tjerk P; Petridou, Natalia; Dumoulin, Serge O; Harvey, Ben M; Aarnoutse, Erik J; Kenemans, J Leon; Neggers, Sebastian F W

    2015-04-22

    Preparation for an action, such as grasping an object, is accompanied by an enhanced perception of the object's action-relevant features, such as orientation and size. Cortical feedback from motor planning areas to early visual areas may drive this enhanced perception. To examine whether action preparation modulates activity in early human visual cortex, subjects grasped or pointed to oriented objects while high-resolution fMRI data were acquired. Using multivoxel pattern analysis techniques, we could decode with >70% accuracy whether a grasping or pointing action was prepared from signals in visual cortex as early as V1. These signals in early visual cortex were observed even when actions were only prepared but not executed. Anterior parietal cortex, on the other hand, showed clearest modulation for actual movements. This demonstrates that preparation of actions, even without execution, modulates relevant neuronal populations in early visual areas.

  15. A new cleaner process to prepare pressing-powder

    Directory of Open Access Journals (Sweden)

    Shu, Z.

    2011-10-01

    Full Text Available An alternative cleaner process of pressing-powder preparation, based on filter-pressing and a novel granulation method, is presented to substitute the existing spray-drying process. In the new process, about two-thirds of wet-milled slurry is filterpressed, dried and milled into dry fine powder. The other one-third of the slurry and the as-obtained dry fine powder are spray-mixed in a tower, where the slurry droplets adsorb the dry powder to form granules which are then rolled and dried into a useable pressing-powder for tile pressing. The key stages, filter-pressing and granulation (consisting of spray-mixing and rolling treatment, are specially studied. The pressing-powder properties and pressing/firing behavior, and, energy/water consumption and pollution emission data are presented, and a comparison between the new process and the existing spray-drying process is made. This new process has been found to be feasible and provides a pressing-powder with suitable properties, together with lower energy/water consumption and pollution emission (particulate matter and CO2.

    En ese trabajo se presenta un proceso alternativo y más ecológico para la preparación de polvo de prensas por molienda vía húmeda de las materias primas. En este proceso la eliminación del agua de la suspensión obtenida en la etapa de molienda, en vez de realizarse por secado por atomización, se lleva a cabo en dos etapas, en una primera etapa dos tercios de esta suspensión se filtro-prensan, posteriormente se secan y molturan hasta obtener un polvo seco micronizado. Este material seco se introduce por la parte superior de una torre granuladora, en la que se pulveriza el tercio de la suspensión restante por la parte inferior, de forma que las gotas adsorben sobre su superficie las partículas secas formando gránulos, que posteriormente se compactan por rodamiento (“rolling”, y finalmente se secan hasta la humedad requerida para el prensado. En

  16. A process for the preparation of cysteine from cystine

    Science.gov (United States)

    Chang, Shih-Ger; Liu, David K.; Griffiths, Elizabeth A.; Littlejohn, David

    1989-01-01

    The present invention in one aspect relates to a process for the simultaneous removal of NO.sub.x and SO.sub.2 from a fluid stream comprising mixtures thereof and in another aspect relates to the separation, use and/or regeneration of various chemicals contaminated or spent in the process and which includes the steps of: (A) contacting the fluid stream at a temperature of between about 105.degree. and 180.degree. C. with a liquid aqueous slurry or solution comprising an effective amount of an iron chelate of an amino acid moiety having at least one --SH group; (B) separating the fluid stream from the particulates formed in step (A) comprising the chelate of the amino acid moiety and fly ash; (C) washing and separating the particulates of step (B) with an aqeous solution having a pH value of between about 5 to 8; (D) subsequently washing and separating the particulates of step (C) with a strongly acidic aqueous solution having a pH value of between about 1 to 3; (E) washing and separating the particulates of step (D) with an basic aqueous solution having a pH value of between about 9 to 12; (F) optionally adding additional amino acid moiety, iron (II) and alkali to the aqueous liquid from step (D) to produce an aqueous solution or slurry similar to that in step (A) having a pH value of between about 4 to 12; and (G) recycling the aqueous slurry of step (F) to the contacting zone of step (A). Steps (D) and (E) can be carried out in the reverse sequence, however the preferred order is (D) and then (E). In a preferred embodiment the present invention provides an improved process for the preparation (regeneration) of cysteine from cystine, which includes reacting an aqueous solution of cystine at a pH of between about 9 to 13 with a reducing agent selected from hydrogen sulfide or alkali metal sulfides, sulfur dioxide, an alkali metal sulfite or mixtures thereof for a time and at a temperature effective to cleave and reduce the cystine to cysteine with subsequent

  17. Preparation of porcelain tile granulates by more environmentally sustainable processes

    Directory of Open Access Journals (Sweden)

    García-Ten, J.

    2012-04-01

    Full Text Available This study examines the feasibility of manufacturing glazed porcelain tiles with a more environmentally friendly manufacturing process, by reducing water and thermal energy consumption. The process studied in this paper is dry milling in a pendulum mill, with subsequent granulation (in order to obtain a press powder with similar flowability to that of spraydried powders. The different morphology of the new granulate with respect to the standard spray-dried granulate modifies the microstructure of the green compacts and thus, their behaviour and fired tile properties. In order to obtain porcelain tiles with the required properties (water absorption, mechanical strength,… changes have been made in the raw materials mixture and in the processing variables. Finally, porcelain tiles measuring 50x50 cm have been manufactured at industrial scale with the new granulate using a conventional firing cycle, obtaining quality levels identical to those provided by the spray-dried granulate. These results open the possibility of preparing porcelain tile body compositions through a manufacturing process alternative to the standard one, more environmentally friendly and with lower costs.

    En el presente trabajo se ha estudiado la viabilidad de fabricar gres porcelánico esmaltado utilizando un sistema de preparación de la composición del soporte más respetuoso con el medio ambiente, lo que implica una reducción importante de los consumos de agua y de energía térmica. El proceso que se estudia en el presente trabajo es el consistente en la molienda vía seca en molino pendular y en la posterior granulación (para obtener un polvo de prensas con fluidez similar a la de los polvos atomizados. La distinta morfología de los nuevos gránulos obtenidos respecto al polvo atomizado actual, modifica la microestuctura en crudo de las piezas y, con ello, el comportamiento y propiedades finales de las baldosas obtenidas. Por ello, ha sido necesario

  18. [Preparation of recombinant human insulin--study of downstream process].

    Science.gov (United States)

    Yu, Rong; Li, Xiaohong; Yang, Jiyu; Wu, Wutong

    2004-10-01

    This study was intended to establish a method of preparation of recombinant human insulin, with (His)6-Arg-Arg-human proinsulin (RRhPI) expressed by Escherichia coli. After DEAE-Sepharose Fast Flow ion-exchange chromatography, Sephadex G-25 chromatography and refolding, enzyme cleavage and Superdex 75 size exclusion chromatography,the RRhPI expressed by Escherichia coli in inclusion body form was converted to human insulin. The obtained recombinant human insulin was analyzed by SDS-PAGE, HPLC, amino acid composition analysis and bioidentity test (mouse convulsion test). The results indicate that our obtained preparation is highly purified, active recombinant human insulin.

  19. 7 CFR 1781.17 - Docket preparation and processing.

    Science.gov (United States)

    2010-01-01

    ..., DEPARTMENT OF AGRICULTURE (CONTINUED) RESOURCE CONSERVATION AND DEVELOPMENT (RCD) LOANS AND WATERSHED (WS..., WS advances and RCD loans will be prepared in accordance with the applicable provisions of part 1780... preliminary draft of the watershed plan or RCD area plan, together with an estimate of costs and benefits...

  20. A Convenient Process for the Preparation of Heteroaryl Trifluoromethyl Selenoethers

    Institute of Scientific and Technical Information of China (English)

    Qinli Tian; Zhiqiang Weng

    2016-01-01

    The preparation of heteroaryl trifluoromethyl selenoethers by the trifluoromethylselenolation of heteroaryl bromides with [(bpy)CuSeCF3]2 was investigated.Using this approach,a large number of trifluoromethylselenolated heterocyclic compounds were synthesized in good to excellent yields.It was demonstrated that this procedure tolerates a wide variety of functional groups.

  1. Process for preparing fine-grain metal carbide powder

    Science.gov (United States)

    Kennedy, C.R.; Jeffers, F.P.

    Fine-grain metal carbide powder suitable for use in the fabrication of heat resistant products is prepared by coating bituminous pitch on SiO/sub 2/ or Ta/sub 2/O/sub 5/ particles, heating the coated particles to convert the bituminous pitch to coke, and then heating the particles to a higher temperature to convert the particles to a carbide by reaction of said coke therewith.

  2. Supramyl, a process step for the preparation of energy alcohol

    Energy Technology Data Exchange (ETDEWEB)

    Misselhorn, K.

    1981-01-01

    A continuous process for EtOH manufacture from starch-containing materials (potato, manioc, maize, and wheat) is described and the energy requirements for the process and the conventional process are compared. The materials are mixed with alpha-amylase and CaO and heated with steam in a continuous starch-digestion unit. The temperature effect on viscosity of the mash, the dextrose equivalent as function of time and enzyme concentration, and retrogradation for various raw materials are discussed. The respective energy consumption for starch mashing, distillation, and spent-wash evaporation and drying for the conventional process are 8.0, 10.9, and 10.9 and the respective energy consumptions for the continuous process are 0.7, 5.8, and 8.1 MJ/l EtOH.

  3. Electrochemical process for the preparation of nitrogen fertilizers

    Science.gov (United States)

    Aulich, Ted R.; Olson, Edwin S.; Jiang, Junhua

    2013-03-19

    The present invention provides methods and apparatus for the preparation of nitrogen fertilizers including ammonium nitrate, urea, urea-ammonium nitrate, and/or ammonia utilizing a source of carbon, a source of nitrogen, and/or a source of hydrogen. Implementing an electrolyte serving as ionic charge carrier, (1) ammonium nitrate is produced via the reduction of a nitrogen source at the cathode and the oxidation of a nitrogen source at the anode; (2) urea or its isomers are produced via the simultaneous cathodic reduction of a carbon source and a nitrogen source; (3) ammonia is produced via the reduction of nitrogen source at the cathode and the oxidation of a hydrogen source at the anode; and (4) urea-ammonium nitrate is produced via the simultaneous cathodic reduction of a carbon source and a nitrogen source, and anodic oxidation of a nitrogen source. The electrolyte can be solid.

  4. Preparation of inverted medium and processing in the inverted medium

    Energy Technology Data Exchange (ETDEWEB)

    Zafarullah, Ijaz [Department of Physics, Montana State University, Bozeman, MT 59717 (United States)]. E-mail: ijaz@montana.edu; Tian Minghzen [Department of Physics, Montana State University, Bozeman, MT 59717 (United States); Chang Tiejun [The Spectrum Laboratory, Montana State University, Bozeman, MT 59717 (United States); Randall Babbitt, W. [Department of Physics, Montana State University, Bozeman, MT 59717 (United States)

    2007-11-15

    The processing of weak optical signals in spatial-spectral holographic (SSH) materials coherently inverted with optical frequency chirped pulses were investigated. Simulations and experimental studies in Tm{sup 3+}:YAG were conducted to characterize the parameters of the frequency chirped laser pulse used to invert the SSH material in order to obtain high photon echo efficiency for SSH lidar processing. Collinear and angled beam geometries and single shot and accumulated processes were investigated. Echo efficiencies as high as 450% were measured, significantly higher than the typical stimulated photon echo efficiency of 10%.

  5. Copper base materials prepared by gel-casting process

    Institute of Scientific and Technical Information of China (English)

    LIU Weihua; JIA Chengchang; SHI Yantao; HAN Yuepeng

    2008-01-01

    Gel-casting process was developed as a new molding process in the field of copper base powder metallurgy to manufacture metal parts with excellent performance and complex shapes.Through changing the parameters of gel-casting process,such as dispersant and solid loading,the corresponding effects on the rheology of Cu slurries,molding and sintering behaviors were studied.The results show that the viscosity of Cu slurries was significantly reduced with an increase in dispersant.The most appropriate solid loading was found to be 61% and the sintering temperature was 910℃ in these experiments.After the optimization of parameters of gel-casting process,copper composite parts with relatively high density and better properties were obtained.

  6. [Impurity removal technology of Tongan injection in liquid preparation process].

    Science.gov (United States)

    Yang, Xu-fang; Wang, Xiu-hai; Bai, Wei-rong; Kang, Xiao-dong; Liu, Jun-chao; Wu, Yun; Xiao, Wei

    2015-08-01

    In order to effectively remove the invalid impurities in Tongan injection, optimize the optimal parameters of the impurity removal technology of liquid mixing process, in this paper, taking Tongan injection as the research object, with the contents of celandine alkali, and sinomenine, solids reduction efficiency, and related substances inspection as the evaluation indexes, the removal of impurities and related substances by the combined process of refrigeration, coction and activated carbon adsorption were investigated, the feasibility of the impurity removal method was definited and the process parameters were optimized. The optimized process parameters were as follows: refrigerated for 36 h, boiled for 15 min, activated carbon dosage of 0.3%, temperature 100 degrees C, adsorption time 10 min. It can effectively remove the tannin, and other impurities, thus ensure the quality and safety of products.

  7. Preparation

    Directory of Open Access Journals (Sweden)

    M.M. Dardir

    2014-03-01

    Full Text Available Some hexanamide-mono and di-linoleniate esters were prepared by the reaction of linolenic acid and hexanamide (derived from the reaction of hexanoic acid and diethanolamine. The chemical structure for the newly prepared hexanamide-mono and di-linoleniate esters were elucidated using elemental analysis, (FTIR, H 1NMR and chemical ionization mass spectra (CI/Ms spectroscopic techniques. The results of the spectroscopic analysis indicated that they were prepared through the right method and they have high purity. The new prepared esters have high biodegradability and lower toxicity (environmentally friendly so they were evaluated as a synthetic-based mud (ester-based mud for oil-well drilling fluids. The evaluation included study of the rheological properties, filtration and thermal properties of the ester based-muds formulated with the newly prepared esters compared to the reference commercial synthetic-based mud.

  8. Design Automation Systems for Production Preparation : Applied on the Rotary Draw Bending Process

    OpenAIRE

    Johansson, Joel

    2008-01-01

    Intensive competition on the global market puts great pressure on manufacturing companies to develop and produce products that meet requirements from customers and investors. One key factor in meeting these requirements is the efficiency of the product development and the production preparation process. Design automation is a powerful tool to increase efficiency in these two processes. The benefits of automating the production preparation process are shortened led-time, improved product perfo...

  9. Electrochemical process for the preparation of nitrogen fertilizers

    Energy Technology Data Exchange (ETDEWEB)

    Aulich, Ted R [Grand Forks, ND; Olson, Edwin S [Grand Forks, ND; Jiang, Junhua [Grand Forks, ND

    2012-04-10

    The present invention provides methods and apparatus for the preparation of nitrogen fertilizers including ammonium nitrate, urea, urea-ammonium nitrate, and/or ammonia, at low temperature and pressure, preferably at ambient temperature and pressure, utilizing a source of carbon, a source of nitrogen, and/or a source of hydrogen or hydrogen equivalent. Implementing an electrolyte serving as ionic charge carrier, (1) ammonium nitrate is produced via the reduction of a nitrogen source at the cathode and the oxidation of a nitrogen source at the anode; (2) urea or its isomers are produced via the simultaneous cathodic reduction of a carbon source and a nitrogen source; (3) ammonia is produced via the reduction of nitrogen source at the cathode and the oxidation of a hydrogen source or a hydrogen equivalent such as carbon monoxide or a mixture of carbon monoxide and hydrogen at the anode; and (4) urea-ammonium nitrate is produced via the simultaneous cathodic reduction of a carbon source and a nitrogen source, and anodic oxidation of a nitrogen source. The electrolyte can be aqueous, non-aqueous, or solid.

  10. A process for preparation of anticancer drug 9-nitro camptothecin

    Institute of Scientific and Technical Information of China (English)

    FU Qing-Quan; CHEN Zhi-Yong; WANG Yuan-Hua; LIU Wei-Jun; HUANG Hao-Xi; HU Wen-Hao

    2004-01-01

    Camptothecin and some of its semisythetic derivatives such as topotecan, irinotecan and 9-nitrocamptothecin, have exhibited strong antitumor activity against various experimental tumor model. The water insoluble 9-nitrocamptothecin demonstrated very potent antitumor activity against many different types of human cancers and HIV. Literature procedures for preparing 9-nitrocamptothecin are direct nitration of camptothecin using a concentrated nitric/concentrated sulfuric acid system or a combination of two or more different nitrate salts/concentrated sulfuric acid system. The two systems demand on the chromatographically separation, which is a hindrance to industrial production. We found that the main products of nitration of camptothecin,9-nitrocamptothecin and 12-nitrocamptothecin, have the great difference for the solubility in the organic solvent. So we studied various organic solvent for the crude product obtained from nitration of camptothecin using KNO3/concentrated sulfuric acid system. At last we found that the ethyl acetate is the best solvent for extraction of the reaction solution and tchloroform and the ether is the best solvent for recrystalization by screening various polarity of organic solvent.

  11. Application of a power quality analyser to the monitoring of sand preparation processes in foundry plants

    Directory of Open Access Journals (Sweden)

    K. Smyksy

    2011-10-01

    Full Text Available Process control plays a major role in supervision and identification of states, for example in monitoring of electric circuits power- supplying the foundry machines and devices, such as sand preparation processes, moulding technologies, melting, cleaning and finishing of castings. The monitoring and control equipment includes the power quality analysers. Testing is done using a Japanese analyser KEW 6319 (Kyoritsu applied to monitoring of the sand preparation process in a foundry plant with low level of mechanization, equipped with the sand preparation unit based on a roller mixer.

  12. Elementary Education Curriculum Folio Guidelines for the NCATE Review Process: Basic Preparation.

    Science.gov (United States)

    Quisenberry, Nancy L.

    This publication provides guidelines for institutions of higher education preparing an Elementary Education Curriculum Folio for review by the Association for Childhood Education International (ACEI). Preparation of folios is part of the National Council for Accreditation of Teacher Education (NCATE) accreditation process. The completed form and…

  13. The methodology of wavelet analysis as a tool for cytology preparations image processing

    Directory of Open Access Journals (Sweden)

    Vyacheslav V. Lyashenko

    2016-09-01

    Conclusion: Consider the possibility and feasibility issues of applying wavelet analysis for processing cytology preparations images. This improves the quality of the analysis of cytology preparations images. This allows the to properly diagnose. [Cukurova Med J 2016; 41(3.000: 453-463

  14. Fieldcrest Cannon, Inc. Advanced Technical Preparation. Statistical Process Control (SPC). PRE-SPC I. Instructor Book.

    Science.gov (United States)

    Averitt, Sallie D.

    This instructor guide, which was developed for use in a manufacturing firm's advanced technical preparation program, contains the materials required to present a learning module that is designed to prepare trainees for the program's statistical process control module by improving their basic math skills and instructing them in basic calculator…

  15. Integrated process for preparing a carboxylic acid from an alkane

    Science.gov (United States)

    Benderly, Abraham; Chadda, Nitin; Sevon, Douglass

    2011-12-20

    The present invention relates to an integrated process for producing unsaturated carboxylic acids from the corresponding C.sub.2-C.sub.4 alkane. The process begins with performance of thermally integrated dehydrogenation reactions which convert a C.sub.2-C.sub.4 alkane to its corresponding C.sub.2-C.sub.4 alkene, and which involve exothermically converting a portion of an alkane to its corresponding alkene by oxidative dehydrogenation in an exothermic reaction zone, in the presence of oxygen and a suitable catalyst, and then feeding the products of the exothermic reaction zone to an endothermic reaction zone wherein at least a portion of the remaining unconverted alkane is endothermically dehydrogenated to form an additional quantity of the same corresponding alkene, in the presence of carbon dioxide and an other suitable catalyst. The alkene products of the thermally integrated dehydrogenation reactions are then provided to a catalytic vapor phase partial oxidation process for conversion of the alkene to the corresponding unsaturated carboxylic acid or nitrile. Unreacted alkene and carbon dioxide are recovered from the oxidation product stream and recycled back to the thermally integrated dehydrogenation reactions.

  16. Effects of the grinding process on the preparation and qualities of CWS

    Institute of Scientific and Technical Information of China (English)

    Yuliang Zhang; Guoguang Wu; Xianliang Meng; Zengjie Yun; Frank Shi; Yaqun He; Xiaoqiang Luo

    2011-01-01

    Two different grinding processes were examined to determine the effect grinding has on the quality of a CWS.A series of slurries was prepared from Australian (Au) and Chinese (YZ) coals.Both types of coal were ground by a Chinese (CUMT) and an Australian (JK) grinding process.The performance tests of the prepared CWS showed that fluidity of all slurries was acceptable.The concentration of the CWS from YZ coal ground by the CUMT grinding process was higher than when the JK grinding process was used.The highest concentration was 70.14% in this case.The concentration of the CWS prepared from Au coal by the JK grinding process was higher than when the CUMT grinding process was used.The highest concentration in this case was 70.97%.These differences are caused by the particle size distribution developed during the different grinding processes.

  17. Preparation of montmorillonite modified phenolic resin for shell process

    Institute of Scientific and Technical Information of China (English)

    Xiong Jianmin; Li Yuancai; Wang Wenqing; Xia Chun

    2009-01-01

    The development of montmodllonite modified phenolic resin under microwave irradiation heating was investigated. The effect of montmorillonite content and stirring time on the structure and morphology of synthetic resin was analyzed. The optimum processing procedure was found to be 45 rain stirring time with 5.4% montmorillonite addition. Further, the platelet spacing increases with stirring time till montmorillonite exfoliated to nanoscales platelet. When montmorillonite is exfoliated, layered structure at nanoscale can be uniformly distributed in the resin. The overall performance of montmorillonite modified phenolic resin is improved remarkably, such as flow ability, tensile strength and toughness property of resin coated sand. However, the gelation speed decreased slightly by adding montmorillonite.

  18. Preparation of Wear Resistant Materials by Melting and Diffusion Process

    Institute of Scientific and Technical Information of China (English)

    YU Shihao; WEI Xueping; ZENG Hui

    2012-01-01

    A wear-resistant material reinforced with VCp was manufactured by the in-mold melting process,in which the high-vanadium alloy-rods were melted by high temperature liquid steel and elements diffused into the liquid.Microstructure of the material was examined by OM,SEM,and XRD,and alloy elements in the diffusion layer were studied by EDS,and the hardness of the material was tested by HRS.The experimental results show that the material gradually changes hardness,which is due to the uniformly existents of carbide particles on martensite matrix and the gradient distribution of vanadium and carbide.

  19. Stable free-radical forms of plasma proteins or simpler related structures which induce brain excitatory effects.

    Science.gov (United States)

    Polis, B D; Wyeth, J; Goldstein, L; Graedon, J

    1969-10-01

    Stable free radicals have been prepared from purified plasma proteins, pituitary peptides, and simpler related structures like 5-OH tryptophan and melatonin by oxidation with the free-radical nitrosyl disulfonate in alkaline solution under controlled conditions. The presence of tyrosine or trytophan amino acid residues in the protein was found essential for free-radical formation. These red-colored, stable free radicals showed electron spin resonance spectra in aqueous solutions at room temperature and maintained this characteristic for weeks when stored at 5 degrees C. Illumination, by visible light, of the free-radical proteins and peptides separated from excess nitrosyl disulfonate by salt fractionation or chromatography enhanced the free-radical concentration in the light. The increased signal decayed in the dark. Intravenous administration of the free-radical proteins or peptides into rabbits equipped with chronic cranial electrodes and sedated with a small dose of pentobarbital caused a sudden EEG arousal accompanied by behavioral changes indicative of brain excitation. Illumination of the free-radical compounds prior to administration enhanced the effects. Untreated control proteins or peptides had no effects. The observations are interpreted to suggest the involvement of free-radical structures in the transfer of energy in nervous tissue.

  20. Synthesis and herbicidal activities of pyridyl sulfonylureas:More convenient preparation process of phenyl pyrimidylcarbamates

    Institute of Scientific and Technical Information of China (English)

    Ning Ma; Zhi Jin Fan; Bao Lei Wang; Yong Hong Li; Zheng Ming Li

    2008-01-01

    Four 4-monosubstituted pyrimidine pyridyl sulfonylureas were synthesized from pyridinesulfonamide and phenyl pyrimidyl-carbamate and screened for herbicidal activities.We also reported a convenient preparation process of phenyl pyrimidylcarbamates from pyrimidineamine and phenyl chloroformate.

  1. Heat treatment process of new NdFeB magnet prepared by spark plasma sintering

    Institute of Scientific and Technical Information of China (English)

    李涛; 岳明; 张久兴; 王公平; 肖耀福; 王润

    2003-01-01

    In recent years, spark plasma sintering technique(SPS) has been a focus in the field of material preparation due to its advantages. SPS technique is first introduced for preparation of high quality NdFeB magnets. The effects of heat treatment process on the magnetic properties of SPS NdFeB magnet were investigated. Meanwhile, the effects of heat treatment process on the microstructure, tropism and dimensional precision of the SPS NdFeB magnets were also studied. The high quality NdFeB magnets with fine grains were prepared under proper heat treatment process. The results show that the magnetic properties of SPS NdFeB can be further improved through proper heat treatment process. Meanwhile, the experiment also demonstrates that it is feasible to prepare near-net-shape NdFeB magnets with fine grains and high magnetic property by spark plasma sintering.

  2. A Simpler Understanding of Classic GT: How it is a fundamentally different methodology

    Directory of Open Access Journals (Sweden)

    Ólavur Christiansen

    2007-06-01

    Full Text Available The author reduces the research rationale of classic grounded theory (GT methodology and the consequential classic GT research procedures and stages down to their essential elements. This reduction makes it possible to compare classic GT to other research methodologies in a manner that is simpler and yet concise. This methodological analysis and synthesis has been conducted while applying and after having applied the classic GT methodology in practice in a major project. The fundamental differences between classic GT versus other adaptations of GT, as well as other qualitative-inductive research approaches, are mainly explained by the very different approaches in solving the problem of many equally justifiable interpretations of the same data, and by the consequential differences in research procedures, and how they are applied. Comprehension of methodological differences in details will always be relevant. However, an uncomplicated and still concise explanation of the differences between these methodologies is necessary. “Grounded theory” (GT is used as a common label in the literature for very different research approaches. This simpler approach of comparing the methodologies will be helpful for researchers, who might want to consider several options when deciding which research methodology to use, and who need quickly to understand some of the most essential methodological elements.

  3. Synthetic process for preparation of high surface area electroactive compounds for battery applications

    Energy Technology Data Exchange (ETDEWEB)

    Evenson, Carl; Mackay, Richard

    2013-07-23

    A process is disclosed for the preparation of electroactive cathode compounds useful in lithium-ion batteries, comprising exothermic mixing of low-cost precursors and calcination under appropriate conditions. The exothermic step may be a spontaneous flameless combustion reaction. The disclosed process can be used to prepare any lithium metal phosphate or lithium mixed metal phosphate as a high surface area single phase compound.

  4. Process conditions of preparing methanol from cornstalk gas

    Institute of Scientific and Technical Information of China (English)

    ZHU Ling-feng; DU Lei; LI Xin-bao; LI Guo-ting; ZHANG Jie

    2007-01-01

    The low-heat-value cornstalk gas produced in the down-flow fixed bed gasifier was tentatively used for methanol synthesis. The cornstalk gas was purified and the technical procedures such as deoxygenation, desulfurization, catalytic cracking of tar, purification and hydrogenation were studied. The catalytic experiments of methanol synthesis with cornstalk syngas were carried out in a tubular-flow integral and isothermal reactor. The effect of reaction temperature, pressure, catalysttypes, catalyst particle size, syngas flow at entering end and composition of syngas was investigated. The optimum process conditions and yield of methanol from cornstalk syngas were obtained. The experimental results indicated that the proper catalyst of the synthetic reaction was C301 and the optimum catalyst size (φ) was 0.833 mm×0.351 mm. The optimum operating temperature and pressure were found to be 235℃ and 5 Mpa, respectively. The suitable syngas flow 0.9-1.10 mol/h at entering end was selected and the best composition of syngas were CO 10.49%, CO2 8.8%, N2 37.32%, CnHm 0.95% and H2 40.49%. The best methanol yield is 0.418 g/g cornstalk. The study provided the technical support for the industrial test of methanol production from biomass (cornstalk)gas.

  5. Preparation of thin ceramic monofilaments for TEM observation with novel embedding processes.

    Science.gov (United States)

    Li, Siwei; Feng, Zude; Zhang, Litong; Wang, Yanyan; Chen, Lifu

    2011-01-01

    An applicable method to prepare transmission electron microscopy specimens from ceramic fibers for longitudinal and cross-sectional observations is investigated. The method includes novel embedding processes to fix fibers, a polishing process using a self-manufactured device to get uniformly low thickness (40 μm for L-fiber, 60 μm for C-fiber), a one-side dimpling process to grind the specimen to near electron transparency (about 5 μm in thickness for both L-fiber and C-fiber) and an efficient ion milling process using calculated parameters. These techniques are reliable to accomplish the preparation with high quality in a relatively short time. Many factors related to the preparation processes are discussed.

  6. Power outage estimation for tropical cyclones: improved accuracy with simpler models.

    Science.gov (United States)

    Nateghi, Roshanak; Guikema, Seth; Quiring, Steven M

    2014-06-01

    In this article, we discuss an outage-forecasting model that we have developed. This model uses very few input variables to estimate hurricane-induced outages prior to landfall with great predictive accuracy. We also show the results for a series of simpler models that use only publicly available data and can still estimate outages with reasonable accuracy. The intended users of these models are emergency response planners within power utilities and related government agencies. We developed our models based on the method of random forest, using data from a power distribution system serving two states in the Gulf Coast region of the United States. We also show that estimates of system reliability based on wind speed alone are not sufficient for adequately capturing the reliability of system components. We demonstrate that a multivariate approach can produce more accurate power outage predictions.

  7. Hocodems technology in comparison with conventional separation processes for coal preparation

    Energy Technology Data Exchange (ETDEWEB)

    Wilczynski, P. [Heinrich Holter GmbH, Gladbeck (Germany)

    1999-11-01

    The new Hocodems technology, which is an advanced development of the Larcodems process, is presented and compared with conventional separation processes in coal preparation: Ep values and separation densities for a selected particle size range are compared. Comparisons of investment and operating costs are also made. 2 refs., 4 figs., 2 tabs.

  8. Non-Markovian memory in quantum process tomography and a preparation independent map

    CERN Document Server

    Modi, Kavan

    2010-01-01

    Recently it has been pointed out how differences in preparation procedures for quantum experiments can lead to non-trivial differences in the results of the experiment. The difference arise from the initial correlations between the system and environment. Therefore, any quantum experiment that is prone to the influences from the environment must be prepared carefully. In this paper, we study a quantum process tomography procedure that yields a result independent of the preparation procedure. We investigate the properties of this map and find an approach to distinguish the role of initial correlation in the dynamics of the system.

  9. Expanding the application of the tablet processing workstation to support the sample preparation of oral suspensions.

    Science.gov (United States)

    Opio, Alex Manuel; Nickerson, Beverly; Xue, Gang; Warzeka, John; Norris, Ken

    2011-06-01

    Sample preparation is the most time-consuming part of the analytical method for powder for oral suspension (POS) assay, purity, and preservative analysis, as this involves multiple dilution and filtration steps. The Tablet Processing Workstation (TPW) was used to automate the sample preparation of a POS formulation. Although the TPW is typically used to automate the preparation of solid oral dosage forms and powders, it contains all of the necessary components to perform POS sample preparation. The TPW exhibited acceptable repeatability in testing 3 lots using 10 replicate preparations per lot. Acceptable linearity of the drug and preservative in the presence of excipients was demonstrated over the range corresponding to 50-150% of intent. Accuracy showed suitable recoveries for all points evaluated. TPW results were shown to correlate to results obtained with the manual method. The TPW method was used to prepare samples in support of manufacturing scale-up efforts. With the efficiencies gained using the TPW, it was possible to analyze a large number of samples generated during process development activities for the POS formulation with minimal human intervention. The extensive data enabled trending of the manufacturing development runs and helped to identify optimization strategies for the process.

  10. Preparation of thin ceramic monofilaments for TEM observation with novel embedding processes

    Energy Technology Data Exchange (ETDEWEB)

    Li, Siwei [College of Materials, Key Laboratory of High Performance Ceramic Fibers (Xiamen University), Ministry of Education, Xiamen 361005 (China); National Key Laboratory of Thermostructure Composite Materials, Northwestern Polytechnical University, Xi' an 710072 (China); Feng, Zude, E-mail: zdfeng@xmu.edu.cn [College of Materials, Key Laboratory of High Performance Ceramic Fibers (Xiamen University), Ministry of Education, Xiamen 361005 (China); Zhang, Litong [National Key Laboratory of Thermostructure Composite Materials, Northwestern Polytechnical University, Xi' an 710072 (China); Wang, Yanyan; Chen, Lifu [College of Materials, Key Laboratory of High Performance Ceramic Fibers (Xiamen University), Ministry of Education, Xiamen 361005 (China)

    2011-01-15

    An applicable method to prepare transmission electron microscopy specimens from ceramic fibers for longitudinal and cross-sectional observations is investigated. The method includes novel embedding processes to fix fibers, a polishing process using a self-manufactured device to get uniformly low thickness (40 {mu}m for L-fiber, 60 {mu}m for C-fiber), a one-side dimpling process to grind the specimen to near electron transparency (about 5 {mu}m in thickness for both L-fiber and C-fiber) and an efficient ion milling process using calculated parameters. These techniques are reliable to accomplish the preparation with high quality in a relatively short time. Many factors related to the preparation processes are discussed. -- Research Highlights: {yields}We develop an applicable method to prepare TEM specimens from thin ceramic fibers. {yields}We develop novel embedding processes to enhance the polishing efficiency. {yields}A self-manufactured device is used to get uniformly low thickness. {yields}One-side dimpling method and calculated ion milling process are introduced. {yields}Samples with large thin area for longitudinal and cross-sectional view are obtained.

  11. UO{sub 2} Kernel Preparation by M-EG Process and Its Irradiation Test

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, K. C.; Eom, S. H.; Kim, Y. K.; Yeo, S. H.; Kim, Y. M.; Kim, B. G.; Cho, M. S. [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    Kernels of KAERI TRISO fuels are prepared in the following steps: (1) preparation of a raw material solution(UN solution) by UO{sub 3} (or U{sub 3}O{sub 8}) powder dissolution in the concentrated HNO{sub 3}; (2) broth preparation and physical property control by mixing UN, THFA, PVA, and H{sub 2}O; (3) preparation of spherical liquid gel droplets and dried-ADU gels in sequence through a reaction between uranyl ions and ammonia ions in a gelation column; (4) ageing, washing, and drying processes of ADU gel using AWD equipment; (5) UO{sub 3} calcination by thermal decomposition of driedADU gel in the air; (6) fabrication of UO{sub 2} kernel by reducing the UO{sub 3} and sintering in the H{sub 2}. In this study, improved KAERI processes for UO{sub 2} kernel preparation were presented. ADU gel washing procedure in AWD processes and the heating mode in sintering process were modified and the internal structures of UO{sub 2} kernels are presented as a result.

  12. Testing, Modeling, and Monitoring to Enable Simpler, Cheaper, Longer-Lived Surface Caps

    Energy Technology Data Exchange (ETDEWEB)

    Piet, Steven James; Breckenridge, Robert Paul; Burns, Douglas Edward

    2003-02-01

    Society has and will continue to generate hazardous wastes whose risks must be managed. For exceptionally toxic, long-lived, and feared waste, the solution is deep burial, e.g., deep geological disposal at Yucca Mtn. For some waste, recycle or destruction/treatment is possible. The alternative for other wastes is storage at or near the ground level (in someone’s back yard); most of these storage sites include a surface barrier (cap) to prevent downward water migration. Some of the hazards will persist indefinitely. As society and regulators have demanded additional proof that caps are robust against more threats and for longer time periods, the caps have become increasingly complex and expensive. As in other industries, increased complexity will eventually increase the difficulty in estimating performance, in monitoring system/component performance, and in repairing or upgrading barriers as risks are managed. An approach leading to simpler, less expensive, longer-lived, more manageable caps is needed. Our project, which started in April 2002, aims to catalyze a Barrier Improvement Cycle (iterative learning and application) and thus enable Remediation System Performance Management (doing the right maintenance neither too early nor too late). The knowledge gained and the capabilities built will help verify the adequacy of past remedial decisions, improve barrier management, and enable improved solutions for future decisions. We believe it will be possible to develop simpler, longer-lived, less expensive caps that are easier to monitor, manage, and repair. The project is planned to: a) improve the knowledge of degradation mechanisms in times shorter than service life; b) improve modeling of barrier degradation dynamics; c) develop sensor systems to identify early degradation; and d) provide a better basis for developing and testing of new barrier systems. This project combines selected exploratory studies (benchtop and field scale), coupled effects accelerated aging

  13. Testing, Modeling, and Monitoring to Enable Simpler, Cheaper, Longer-lived Surface Caps

    Energy Technology Data Exchange (ETDEWEB)

    Piet, S. J.; Breckenridge, R. P.; Burns, D. E.

    2003-02-25

    Society has and will continue to generate hazardous wastes whose risks must be managed. For exceptionally toxic, long-lived, and feared waste, the solution is deep burial, e.g., deep geological disposal at Yucca Mtn. For some waste, recycle or destruction/treatment is possible. The alternative for other wastes is storage at or near the ground level (in someone's back yard); most of these storage sites include a surface barrier (cap) to prevent downward water migration. Some of the hazards will persist indefinitely. As society and regulators have demanded additional proof that caps are robust against more threats and for longer time periods, the caps have become increasingly complex and expensive. As in other industries, increased complexity will eventually increase the difficulty in estimating performance, in monitoring system/component performance, and in repairing or upgrading barriers as risks are managed. An approach leading to simpler, less expensive, longer-lived, more manageable caps is needed. Our project, which started in April 2002, aims to catalyze a Barrier Improvement Cycle (iterative learning and application) and thus enable Remediation System Performance Management (doing the right maintenance neither too early nor too late). The knowledge gained and the capabilities built will help verify the adequacy of past remedial decisions, improve barrier management, and enable improved solutions for future decisions. We believe it will be possible to develop simpler, longer-lived, less expensive caps that are easier to monitor, manage, and repair. The project is planned to: (a) improve the knowledge of degradation mechanisms in times shorter than service life; (b) improve modeling of barrier degradation dynamics; (c) develop sensor systems to identify early degradation; and (d) provide a better basis for developing and testing of new barrier systems. This project combines selected exploratory studies (benchtop and field scale), coupled effects

  14. Preparation of Hollow Spherical and Core/shell Structured Powders by Plasma Processing

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Xiaofeng; ZHOU; Kesong; DENG; Changguang; SONG; Jinbing; ZHANG; Jifu; DONG; Shujuan

    2015-01-01

    Four types of hollow spherical micro- and nano-szied powders of ZrO2-7wt.%Y2O3(7YSZ), ZrO2-7wt.%Y2O3, Al2O3-13 wt.% TiO2(AT) and WC as well as one type of core/shell structured powder of ZrB2-30 wt.%Mo Si2 were prepared via plasma processing. In addition, the formation mechanisms of hollow spherical and core/shell structured powders prepared via plasma processing were also proposed.

  15. Optimization of preparation process and characterization of carboxymethyl chitosan/sodium alginate hemostatic sponge

    Science.gov (United States)

    Hu, Z.; Ouyang, Q. Q.; Cheng, Y.; Hong, P. Z.; Liao, M. N.; Chen, F. J.; Li, S. D.

    2017-06-01

    Composite hemostatic sponge was prepared by vacuum freeze-drying using carboxymethyl chitosan and sodium alginate as the main materials and CaCl2 as a crosslinking agent. On the basis of single factor experiments, an orthogonal experiment was carried out to optimize the preparation process of hemostatic sponge. The appearance, water absorption, porosity ratio, and in vitro hemostasis of the sponge were evaluated. The optimum conditions to prepare hemostatic sponge were obtained as follows: mass ratio of sodium alginate to carboxymethyl chitosan 4: 1, mass fraction of CaCl2 2%, and crosslinking temperature 30°C. The hemostatic sponge prepared under such conditions was off-white and porous. Its water absorption and porosity ratio were 3050% and 67.23%, respectively. Meanwhile, the hemostatic sponges had significant in vitro procoagulant activity. Therefore, the hemostatic sponge is expected to be developed as a novel medical material.

  16. Preparation and modification of carbon nanotubes electrodes by cold plasmas processes toward the preparation of amperometric biosensors

    Energy Technology Data Exchange (ETDEWEB)

    Luais, E. [CEISAM, Universite de Nantes, CNRS, 2 rue de la Houssiniere, 44322 Nantes cedex 3 (France); IMN, Universite de Nantes, CNRS, 2 rue de la Houssiniere, 44322 Nantes cedex 3 (France); PCI, Universite du Maine, CNRS, rue Aristote, 72085 Le Mans cedex 9 (France); Thobie-Gautier, C. [CEISAM, Universite de Nantes, CNRS, 2 rue de la Houssiniere, 44322 Nantes cedex 3 (France); Tailleur, A.; Djouadi, M.-A.; Granier, A.; Tessier, P.Y. [IMN, Universite de Nantes, CNRS, 2 rue de la Houssiniere, 44322 Nantes cedex 3 (France); Debarnot, D.; Poncin-Epaillard, F. [PCI, Universite du Maine, CNRS, rue Aristote, 72085 Le Mans cedex 9 (France); Boujtita, M., E-mail: mohammed.boujtita@univ-nantes.f [CEISAM, Universite de Nantes, CNRS, 2 rue de la Houssiniere, 44322 Nantes cedex 3 (France)

    2010-11-30

    An electrochemical transducer based on vertically aligned carbon nanotubes (CNT) was prepared as a platform for biosensor development. Prior to enzyme immobilization, the CNT were treated using a microwave plasma system (CO{sub 2} and N{sub 2}/H{sub 2}) in order to functionalize the CNT surface with oxygenated and aminated groups. The morphological aspect of the electrode surface was examined by SEM and its chemical structure was also elucidated by XPS analysis. It was found out that microwave plasma system (CO{sub 2} and N{sub 2}/H{sub 2}) not only functionalizes the CNT but also permits to avoid the collapse phenomena retaining thus the alignment structure of the electrode surface. The electrochemical properties of the resulting new material based on CNT were carried out by cyclic voltammetry and were found suitable to develop high sensitive enzyme (HRP) biosensors operating on direct electron transfer process.

  17. A new simpler rotation/curvature correction method for Spalart-Allmaras turbulence model

    Institute of Scientific and Technical Information of China (English)

    Zhang Qiang; Yang Yong

    2013-01-01

    A new and much simpler rotation and curvature effects factor,which takes the form of Richardson number suggested by Hellsten originally for SST k-ω model,is presented for Spalart and Shur's rotation and curvature correction in the context of Spalart-Allmaras (SA) turbulence model.The new factor excludes the Lagrangian derivative of the strain rate tensor that exists in the SARC model,resulting in a simple,efficient and easy-to-implement approach for SA turbulence model (denoted as SARCM) to account for the effects of system rotation and curvature,techniquely.And then the SARCM is tested through turbulent curved wall flows:one is the flow over a zeropressure-gradient curved wall and the other is the channel flow in a duct with a U-turn.Predictions of the SARCM model are compared with experimental data and with the results obtained using original SA and SARC models.The numerical results show that SARCM can predict the rotation-curvature effects as accurately as SARC,but considerably more efficiently.Additionally,the accuracy of SARCM might strongly depend on the rotation-curvature model constants.Suggesting values for those constants are given,after some trials and errors.

  18. The B-Skip-List: A Simpler Uniquely Represented Alternative to B-Trees

    CERN Document Server

    Golovin, Daniel

    2010-01-01

    In previous work, the author introduced the B-treap, a uniquely represented B-tree analogue, and proved strong performance guarantees for it. However, the B-treap maintains complex invariants and is very complex to implement. In this paper we introduce the B-skip-list, which has most of the guarantees of the B-treap, but is vastly simpler and easier to implement. Like the B-treap, the B-skip-list may be used to construct strongly history-independent index structures and filesystems; such constructions reveal no information about the historical sequence of operations that led to the current logical state. For example, a uniquely represented filesystem would support the deletion of a file in a way that, in a strong information-theoretic sense, provably removes all evidence that the file ever existed. Like the B-tree, the B-skip-list has depth O(log_B (n)) where B is the block transfer size of the external memory, uses linear space with high probability, and supports efficient one-dimensional range queries.

  19. Computational and nonglycosylated systems: a simpler approach for development of nanosized PEGylated proteins.

    Science.gov (United States)

    Mirzaei, Hadi; Kazemi, Bahram; Bandehpour, Mojgan; Shoari, Alireza; Asgary, Vahid; Ardestani, Mehdi Shafiee; Madadkar-Sobhani, Armin; Cohan, Reza Ahangari

    2016-01-01

    Cysteine PEGylation includes several steps, and is difficult to manage in practice. In the current investigation, the cysteine PEGylation of erythropoietin analogs was examined using computational and nonglycosylated systems to define a simpler approach for specific PEGylation. Two model analogs (E31C and E89C) were selected for PEGylation based on lowest structural deviation from the native form, accessibility, and nucleophilicity of the free thiol group. The selected analogs were cloned and the expression was assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot using Coomassie blue staining and anti-His monoclonal antibody, respectively. PEGylation with 20 kDa mPEG-maleimide resulted in 79% and 82% conjugation yield for E31C and E89C nonglycosylated erythropoietin (ngEPO) analogs, respectively. The size distribution and charge analysis showed an increase in size and negative charge of the PEGylated forms compared with nonconjugated ones. Biological assay revealed that E31C and E89C mutations and subsequent PEGylation of ngEPO analogs have no deleterious effects on in vitro biological activity when compared to CHO-derived recombinant human erythropoietin. In addition, PEG-conjugated ngEPOs showed a significant increase in plasma half-lives after injection into rats when compared to nonconjugated ones. The development of the cysteine-PEGylated proteins using nonglycosylated expression system and in silico technique can be considered an efficient approach in terms of optimization of PEGylation parameters, time, and cost.

  20. Porphyrinosilica and metalloporphyrinosilica: hybrid organic-inorganic materials prepared by sol-gel processing

    Directory of Open Access Journals (Sweden)

    YASSUKO IAMAMOTO

    2000-03-01

    Full Text Available New materials porphyrinosilica and metalloporphyrinosilica template have been obtained by a sol-gel processing where functionalyzed porphyrins and metalloporphyrins "building blocks" were assembled into a three-dimensional silicate network. The optimized conditions for preparation of these materials are revised. The monomer precursors porphyrinopropylsilyl and metalloporphyrinopropylsilyl preparation reactions and subsequent one pot sol-gel processing with tetraethoxysilane are discussed. In the case of metalloporphyrins the nitrogen base coordinates to the central metal and acts as a template in the molecular imprinting technique. UV-visible absorption spectroscopy, thermogravimetric analysis, electron paramagnetic resonance, nuclear magnetic spectra, infrared spectra, luminescence spectra, surface area and electron spectroscopy imaging of the materials are used to characterize the prepared materials. The catalytic activities of these metalloporphyrinosilica- template are compared.

  1. A foaming process to prepare porous polymer membrane for lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Li, Z.H. [Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Hunan 411105 (China); New Energy and Materials Laboratory (NEML), Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200433 (China)], E-mail: lzh69@xtu.edu.cn; Cheng, C.; Zhan, X.Y. [Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Hunan 411105 (China); Wu, Y.P. [New Energy and Materials Laboratory (NEML), Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200433 (China)], E-mail: wuyp@fudan.edu.cn; Zhou, X.D. [State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237 (China)

    2009-07-15

    A foaming process was used to prepare porous polymer membranes (PPMs) based on poly(vinylidene diflouride-co-hexafluoropropylene) copolymer for lithium ion batteries. In this simple process, urea, the foaming agent, was decomposed into gases and was removed at an elevated temperature to get the porous structure within the polymer matrix. When the weight ratio of urea to P(VDF-HFP) is 5:6, the PPM presents the highest porosity, 70.2%, and the prepared gelled polymer electrolyte shows an ionic conductivity up to 1.43 x 10{sup -3} S cm{sup -1} at room temperature. This provides another way to prepare gelled polymer electrolytes easily for application in rechargeable lithium batteries.

  2. PROCESS UNIFICATION AND FRAME PREPARATION OF MACHINING PARAMETRES FOR ROTATIONAL PARTS

    Directory of Open Access Journals (Sweden)

    Ersan ASLAN

    2005-01-01

    Full Text Available Any traditional or computerized metal removal process needs a prototype, a technical drawing and a database for production of a part. Design, process planning and manufacturing problems such as modeling, the necessity data extraction from standard data exchange formats, and part programme preparation for machine tools can be solved by the operators or experts as soon as possible while they occurred in the traditonal approach. In circumstances of the production efforts spent by the computer, all experiences of expert can be saved in a database for foresight of the possible problems. This data can be used at any stage in the product cycle. In this paper, it is presented the results of research efforts which aimed to extract information from the defacto industry standard DXF files to determine features existing on rotational parts to be machined on horizontal machining centers. After process extraction and definition, process unifications and frame preparation for machining parameters of the part are introduced.

  3. MULTIAGENT TECHNOLOGIES’ METHOD IN MANAGING BUSINESS-PROCESSES OF THE TECHNICAL PREPARING FOR PRODUCTION

    Directory of Open Access Journals (Sweden)

    P.N. Pavlenko

    2005-02-01

    Full Text Available  The method of managing the process of the extended productions technological preparation is given. The method is used for integrating the automated systems of industrial assignment of  CAD/CAM/SAPP and ERP systems.

  4. Nanostructure Study of TiO2 Films Prepared by Dip Coating Process

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The microstructure properties of the sol-gel derived TiO2 films were studied by the atomic force microscopy (AFM).The films were prepared by dip coating process. The optical properties of the films were explained on the basis ofthe microstructure of the films.

  5. Modelling and analysis of CVD processes in porous media for ceramic composite preparation

    NARCIS (Netherlands)

    Lin, Y.S.; Burggraaf, A.J.

    1991-01-01

    A continuum phenomenological model is presented to describe chemical vapour deposition (CVD) of solid product inside porous substrate media for the preparation of reinforced ceramic-matrix composites [by the chemical vapour infiltration (CVI) process] and ceramic membrane composites (by a modified C

  6. University Strategic Planning: A Process for Change in a Principal Preparation Program

    Science.gov (United States)

    Guerra, Federico R.; Zamora, Roberto; Hernandez, Rosalinda; Menchaca, Velma

    2017-01-01

    This study describes a strategic planning process used for developing an educational leadership program that prepares principals for leading 21st century schools. The plan is based on recommendations received from the External reviewers representing Southern Association of Colleges and Schools, the Texas Education Agency, survey responses received…

  7. Metal nanoparticle deposited inorganic nanostructure hybrids, uses thereof and processes for their preparation

    Science.gov (United States)

    Tenne, Reshef; Tsverin, Yulia; Burghaus, Uwe; Komarneni, Mallikharjuna Rao

    2016-01-26

    This invention relates to a hybrid component comprising at least one nanoparticle of inorganic layered compound (in the form of fullerene-like structure or nanotube), and at least one metal nanoparticle, uses thereof as a catalyst, (e.g. photocatalysis) and processes for its preparation.

  8. Influence of processing on total and extractable mineral content of products prepared from potato flour.

    Science.gov (United States)

    Lakra, Poonam; Sehgal, Salil

    2011-12-01

    Potato (Solanum tuberosum) flour developed was used for preparing doughnuts, sevian, cutlet, kofta and vadi along with defatted soy (Glycine max) flour and corn (Zea mays) flour. Frying and fermentation were the major processing techniques employed for the development of these products. Significant differences in protein, ash and fat contents of all the products were observed due to their compositional differences. Processing did not affect on total mineral content. Processing increased (p mineral availability. Processed products had lower amount of anti nutrients as compared to raw counterparts and thus, higher mineral availability.

  9. A one bath chemo-enzymatic process for preparation of absorbent cotton

    OpenAIRE

    A.S.M. Raja; A. Arputharaj; Sujata Saxena; P.G. Patil

    2016-01-01

    Cotton is the raw material for preparation of absorbent cotton. Raw cotton has to be subjected to scouring and bleaching processes for making it absorbent by removing the naturally present wax, protein and minerals in the fibre. The scouring is done at 115 °C using alkali followed by bleaching at boiling condition using alkaline hydrogen peroxide solution. The effluent coming out of such processes contains high COD and BOD values. Due to the stringent environmental regulation and great awaren...

  10. Photochromic organic-inorganic composite materials prepared by sol-gel processing : properties and potentials

    OpenAIRE

    Hou, Lisong; Mennig, Martin; Schmidt, Helmut K.

    1994-01-01

    The sol-gel method which features a low-temperature wet-chemical process opens vast possibilities to incorporating organic dyes into solid matrices for various optical applications. In this paper we present our experimental results on the sol-gel derived photochromic organic-inorganic composite (ORMOCER) materials follwoing an introductory description of the sol-gel process and a brief review on the state of the art of the photochromic solids prepared using this method. Our photochromic spiro...

  11. Prey, predators, parasites: intraguild predation or simpler community modules in disguise?

    Science.gov (United States)

    Sieber, Michael; Hilker, Frank M

    2011-03-01

    1. Competition and predation are at the heart of community ecology. The theoretical concept of intraguild predation (IGP) combines these key interactions in a single community module. Because IGP is believed to be ubiquitous in nature, it has been subject to extensive research, and there exists a well-developed theoretical framework. 2. We show that a general class of IGP models can be transformed to simpler, but equivalent community structures. This rather unexpected simplification depends critically on the property of 'indiscriminate predation', which we define broadly as the top-predator not distinguishing between its two different prey species. 3. In a broader context, the great importance of IGP and of the simplifying transformation we report here is enhanced by the recent insight that the basic IGP structure extends naturally to host-parasitoid and host-pathogen communities. We show that parasites infecting prey (predators) tend to render IGP effectively into exploitative competition (tritrophic food chain, respectively). 4. The equivalence between the original and simplified community module makes it possible to take advantage from already existing insights. We illustrate this by means of an eco-epidemiological IGP model that is strikingly similar to a classical exploitative competition model. 5. The change of perspective on certain community modules may contribute to a better understanding of food web dynamics. In particular, it may help explain the interactions in food webs that include parasites. Given the ubiquity of parasitism, food webs may appear in a different light when they are transformed to their simplified analogue. © 2010 The Authors. Journal of Animal Ecology © 2010 British Ecological Society.

  12. Utilization of citrus crops processing by-products in the preparation of tarhana

    Directory of Open Access Journals (Sweden)

    Michal Magala

    2015-05-01

    Full Text Available After processing of citrus fruits (e.g. lemon, orange, grapefruit, mandarin for juice and essential oils production, approximately 50% of the original fruit mass is left as waste material. Citrus crops processing by-products are valuable components as they contain nutrients such as pectins, saccharides, carotenoids, some vitamins, minerals, polyphenols and substances with antioxidant activity. Utilisation of these kind of side products in the recipe of various cereal product led to enhancement of final product nutritional value and better sensory attributes as well as improvement of product functional properties. In this work was studied the effect of orange and mandarin dietary fibre application at level 5 and 10% (w/w in tarhana preparation and the influence on tarhana fermentation process. Chemical analysis showed, that dietary fibre preparations reached higher concentration of ash, fat and total dietary fibre compared to wheat flour. Wheat flour exhibited higher moisture content and protein concentration than citrus dietary fibre preparations. Orange and mandarin dietary fibre preparations showed higher values of water and oil absorption capacity, swelling capacity and least gellation concentration compared to wheat flour. Application of fruit dietary fibre preparations to tarhana recipe caused a rapid decrease in pH from 4.70 - 5.02 to values 4.31 - 4.51 during fermentation process. Reducing saccharides served as an available source of energy for fermenting microbiota and their concentration decreased from 24.5 - 32.8 to 2.2 - 0.2 g/kg after 144 h incubation. Fermentation also led to lactic acid (1.67 - 2.09 g/kg and acetic acid (1.91 - 2.53 g/kg production as a consequence of present microorganisms metabolic activity. Sensory evaluation of samples showed, that higher proportion of citrus dietary fibre preparations (10% negatively affected taste, odour, consistency and sourness. Among all prepared tarhana samples with proportion of citrus

  13. An Environmentally Friendly Process for the Preparation of 16-Dehydropregnenolone Acetate

    Institute of Scientific and Technical Information of China (English)

    张焱; 刘颙颙; 程学新; 王雪松; 张宝文

    2005-01-01

    Instead of environmentally toxic chromium oxidant, singlet oxygen generated photcchemically was used as environmentally friendly and benign oxidizing agent to accomplish the transformation of pseudodiosgenin diacetate to diosone efficiently in a low toxic and less expensive solvent acetone. Accordingly 16-dehydropregnenolone acetate(16-DPA), an important intermediate for preparation of steroidal drugs, was prepared in good yield (75%) when photoreaction was run in acetone/acetic anhydride/pyridine system. The mild reaction condition as well as simple and environmentally friendly process made the method commercially viable and important for production of 16-DPA in industrial scale.

  14. Evaluation of the xerovac process for the preparation of heat tolerant contagious bovine pleuropneumonia (CBPP) vaccine.

    Science.gov (United States)

    Litamoi, J K; Ayelet, G; Rweyemamu, M M

    2005-04-01

    The study was conducted with the aim of evaluating the xerovac process as a method for preparing contagious bovine pleuropneumonia (CBPP) vaccine with increased heat resistance. The thermo-protective effects of various concentrations of trehalose in mycoplasma growth medium, various concentrations of trehalose in the dehydration stabilizer and the importance of some divalent cations were assessed. The results obtained indicate that a rapid dehydration of CBPP vaccine following the xerovac method and in an excipient composed of a high concentration of trehalose, renders the product more heat tolerant than a similar vaccine prepared using a regular or an extended freeze drying regime. It was also demonstrated that the addition of chitosan as a mycoplasma precipitating agent conferred additional heat resistance to the vaccine. It is suggested that the application of the xerovac process in the dehydration of CBPP vaccine offers the advantages of a faster, cheaper and easier process over the conventional dehydration methods like freeze drying.

  15. Modeling the Thermal Rocket Fuel Preparation Processes in the Launch Complex Fueling System

    Directory of Open Access Journals (Sweden)

    A. V. Zolin

    2015-01-01

    Full Text Available It is necessary to carry out fuel temperature preparation for space launch vehicles using hydrocarbon propellant components. A required temperature is reached with cooling or heating hydrocarbon fuel in ground facilities fuel storages. Fuel temperature preparing processes are among the most energy-intensive and lengthy processes that require the optimal technologies and regimes of cooling (heating fuel, which can be defined using the simulation of heat exchange processes for preparing the rocket fuel.The issues of research of different technologies and simulation of cooling processes of rocket fuel with liquid nitrogen are given in [1-10]. Diagrams of temperature preparation of hydrocarbon fuel, mathematical models and characteristics of cooling fuel with its direct contact with liquid nitrogen dispersed are considered, using the numerical solution of a system of heat transfer equations, in publications [3,9].Analytical models, allowing to determine the necessary flow rate and the mass of liquid nitrogen and the cooling (heating time fuel in specific conditions and requirements, are preferred for determining design and operational characteristics of the hydrocarbon fuel cooling system.A mathematical model of the temperature preparation processes is developed. Considered characteristics of these processes are based on the analytical solutions of the equations of heat transfer and allow to define operating parameters of temperature preparation of hydrocarbon fuel in the design and operation of the filling system of launch vehicles.The paper considers a technological system to fill the launch vehicles providing the temperature preparation of hydrocarbon gases at the launch site. In this system cooling the fuel in the storage tank before filling the launch vehicle is provided by hydrocarbon fuel bubbling with liquid nitrogen. Hydrocarbon fuel is heated with a pumping station, which provides fuel circulation through the heat exchanger-heater, with

  16. INTRODUCTION OF DISTANCE LEARNING IN EDUCATIONAL PROCESS AT PREPARATION OF INFORMATION TECHNOLOGIES SPECIALISTS

    Directory of Open Access Journals (Sweden)

    Olga R. Harbych-Moshora

    2015-02-01

    Full Text Available Today higher educational institutions should prepare a specialist, who is able to work successfully in globalized market conditions. Accent is made stronger on universal preparation of graduate student and his adaptation to jobs market, as well as on personal orientation of educational process and its informatization. The article considers a concept of distance learning technologies and their support systems. Designed system of distance learning for IT-specialists preparation based on a platform Moodle is a result of the study. The system ensures hierarchic organization of learning courses thanks to using an interactive multimedia clips in Adobe Flash format. As well as there is a possibility to organize various forms of learning and knowledge control.

  17. Titanium carbide/carbon composite nanofibers prepared by a plasma process

    Energy Technology Data Exchange (ETDEWEB)

    El Mel, A A; Gautron, E; Angleraud, B; Granier, A; Tessier, P Y [Universite de Nantes, CNRS, Institut des Materiaux Jean Rouxel, UMR 6502, 2 rue de la Houssiniere BP 32229-44322 Nantes cedex 3 (France); Choi, C H [Department of Mechanical Engineering, Stevens Institute of Technology, Hoboken, NJ 07030 (United States)

    2010-10-29

    The incorporation of metal or metal carbide nanoparticles into carbon nanofibers modifies their properties and enlarges their field of application. The purpose of this work is to report a new non-catalytic and easy method to prepare organized metal carbide-carbon composite nanofibers on nanopatterned silicon substrates prepared by laser interference lithography coupled with deep reactive ion etching. Titanium carbide-carbon composite nanofibers were grown on the top of the silicon lines parallel to the substrate by a hybrid plasma process combining physical vapor deposition and plasma enhanced chemical vapor deposition. The prepared nanofibers were analyzed by scanning electron microscopy, x-ray photoelectron spectroscopy, Raman spectroscopy and transmission electron microscopy. We demonstrate that the shape, microstructure and the chemical composition of the as-grown nanofibers can be tuned by changing the plasma conditions.

  18. Titanium carbide/carbon composite nanofibers prepared by a plasma process.

    Science.gov (United States)

    El Mel, A A; Gautron, E; Choi, C H; Angleraud, B; Granier, A; Tessier, P Y

    2010-10-29

    The incorporation of metal or metal carbide nanoparticles into carbon nanofibers modifies their properties and enlarges their field of application. The purpose of this work is to report a new non-catalytic and easy method to prepare organized metal carbide-carbon composite nanofibers on nanopatterned silicon substrates prepared by laser interference lithography coupled with deep reactive ion etching. Titanium carbide-carbon composite nanofibers were grown on the top of the silicon lines parallel to the substrate by a hybrid plasma process combining physical vapor deposition and plasma enhanced chemical vapor deposition. The prepared nanofibers were analyzed by scanning electron microscopy, x-ray photoelectron spectroscopy, Raman spectroscopy and transmission electron microscopy. We demonstrate that the shape, microstructure and the chemical composition of the as-grown nanofibers can be tuned by changing the plasma conditions.

  19. Pharmaceutical approaches to preparing pelletized dosage forms using the extrusion-spheronization process.

    Science.gov (United States)

    Trivedi, Namrata R; Rajan, Maria Gerald; Johnson, James R; Shukla, Atul J

    2007-01-01

    Pelletized dosage forms date back to the 1950s, when the first product was introduced to the market. Since then, these dosage forms have gained considerable popularity because of their distinct advantages, such as ease of capsule filling because of better flow properties of the spherical pellets; enhancement of drug dissolution; ease of coating; sustained, controlled, or site-specific delivery of the drug from coated pellets; uniform packing; even distribution in the GI tract; and less GI irritation. Pelletized dosage forms can be prepared by a number of techniques, including drug layering on nonpareil sugar or microcrystalline cellulose beads, spray drying, spray congealing, rotogranulation, hot-melt extrusion, and spheronization of low melting materials or extrusion-spheronization of a wet mass. This review discusses recent developments in the pharmaceutical approaches that have been used to prepare pelletized dosage forms using the extrusion-spheronization process over the last decade. The review is divided into three parts: the first part discusses the extrusion-spheronization process, the second part discusses the effect of varying formulation and process parameters on the properties of the pellets, and the last part discusses the different approaches that have been used to prepare pelletized dosage forms using the extrusion-spheronization process.

  20. Influence of process parameters on the preparation of pharmaceutical films by electrostatic powder deposition.

    Science.gov (United States)

    Prasad, Leena Kumari; LaFountaine, Justin S; Keen, Justin M; Williams, Robert O; McGinity, James W

    2016-12-30

    Electrostatic powder deposition (ESPD) has been developed as a solvent-free method to prepare pharmaceutical films. The aim of this work was to investigate the influence of process parameters during (1) electrostatic powder deposition, (2) curing, and (3) removal of the film from the substrate on the properties of the film. Polyethylene oxide (PEO) was used as the model polymer and stainless steel 316 as the substrate. Deposition efficiency (i.e. deposited weight) was measured with varying charging voltage, gun tip to substrate distance, and environmental humidity. Scanning electron microscopy was utilized to assess film formation, and adhesive and mechanical strength of films were measured with varying cure temperature and time. Adhesive strength was measured for films prepared on substrates of varying surface roughness. When deposition was performed at low humidity conditions, 25%RH, process parameters did not significantly affect deposition behavior. At 40%RH, increasing deposition efficiency with decreasing gun tip to substrate distance and increasing voltage (up to 60kV) was observed. Complete film formation was seen by 30min at 80°C, compared to lower curing temperatures and times. All films were readily removed from the substrates. The results show the ESPD process can be modified to produce films with good mechanical properties (e.g. tensile strength>0.06MPa), suggesting it is a promising dry powder process for preparing pharmaceutical films.

  1. Processing practices contributing to Campylobacter contamination in Belgian chicken meat preparations.

    Science.gov (United States)

    Sampers, Imca; Habib, Ihab; Berkvens, Dirk; Dumoulin, Ann; Zutter, Lieven De; Uyttendaele, Mieke

    2008-12-10

    The aim of this study was to obtain insight into processing practices in the poultry sector contributing to the variability in Campylobacter contamination in Belgian chicken meat preparations. This was achieved by company profiling of eleven food business operators, in order to evaluate variation of processing management, in addition to statistical modelling of microbiological testing results for Campylobacter spp. contamination in 656 end product samples. Almost half (48%) of chicken meat preparation samples were positive for Campylobacter spp. Results revealed a statistically significant variation in Campylobacter contamination between 11 chicken meat producers across Belgium at both quantitative and qualitative detection levels. All producers provided Campylobacter-positive samples, but prevalence ranged from 9% up to 85% at single producer level. The presence or addition of skin during production of chicken meat preparations resulted in almost 2.2-fold increase in the probability of a sample being positive for Campylobacter, while chicken meat preparations made from frozen meat, or partly containing pre-frozen meat, had a significant (Odds Ratio=0.41; CI 95% 0.18:0.98) lower probability of being positive for Campylobacter. However, the quantitative results indicated that the positive freezing effect on Campylobacter count was compromised by the presence and/or adding of skin.

  2. Preparation of Spherical Bi2O3 Powder by Plasma and Precipitation Processes

    Institute of Scientific and Technical Information of China (English)

    Chen Peirong; Ji Youzhang; Feng Shifen

    2005-01-01

    Spherical Bi2O3 powder prepared by plasma chemical vapor reaction and aqueous chemical precipitation is studied. The superfine spherical Bi2O3 powder with an average diameter of 1 μm is made by plasma process. During the precipitation process, the micrograph of the Bi2O3 powder can be controlled through the reaction temperature, the rate of addition of the precipitation reagent, the reaction time and the amount of the dispersant. Accordingly, spherical Bi2O3 powder with diameters ranging from 2 μm to 3 μm is prepared. The spherical Bi2 O3particles have such advantages as uniform size distribution and excellent dispersing property.ZnO varistors made from the resultant powder exhibit properties of a low discharge voltage ratio,great eligibility coefficient measured by a rectangle wave of 2 ms 800 A and good stability in the above characteristics.

  3. Dry uranium tetrafluoride process preparation using the uranium hexafluoride reconversion process effluents

    Energy Technology Data Exchange (ETDEWEB)

    Silva Neto, J.B.; Urano de Carvalho, E.F.; Oliveira, F.B.V. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mails: jbsneto@ipen.br; elitaucf@ipen.br; fabio@ipen.br; Riella, H.G. [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil)]. E-mail: riella@enq.ufsc.br

    2007-07-01

    It is a well known fact that the use of uranium tetrafluoride allows flexibility in the production of uranium silicide and uranium oxide fuel. To its obtention there are two conventional routes, the one which reduces uranium from the UF{sub 6} hydrolysis solution with stannous chloride, and the hydrofluorination of a solid uranium dioxide. In this work we are introducing a third and a dry way route, mainly utilized to the recovery of uranium from the liquid effluents generated in the uranium hexafluoride reconversion process, at IPEN/CNEN-SP. Working in the liquid phase, this route comprises the recuperation of ammonium fluoride by NH{sub 4}HF{sub 2} precipitation. Working with the solid residues, the crystallized bifluoride is added to the solid UO{sub 2}, which comes from the U miniplates recovery, also to its conversion in a solid state reaction, to obtain UF{sub 4}. That returns to the process of metallic uranium production unity to the U{sub 3}Si{sub 2} obtention. This fuel is considered in IPEN-CNEN/SP as the high density fuel phase for IEA-R1m reactor, which will replace the former low density U{sub 3}O{sub 8}-Al fuel. (author)

  4. Preparation of sulfurized powdered activated carbon from waste tires using an innovative compositive impregnation process.

    Science.gov (United States)

    Yuan, Chung-Shin; Lin, Hsun-Yu; Wu, Chun-Hsin; Liu, Ming-Han; Hung, Chung-Hsuang

    2004-07-01

    The objective of this study is to develop an innovative compositive impregnation process for preparing sulfurized powdered activated carbon (PAC) from waste tires. An experimental apparatus, including a pyrolysis and activation system and a sulfur (S) impregnation system, was designed and applied to produce sulfurized PAC with a high specific surface area. Experimental tests involved the pyrolysis, activation, and sulfurization of waste tires. Waste-tire-derived PAC (WPAC) was initially produced in the pyrolysis and activation system. Experimental results indicated that the Brunauer-Emmett-Teller (BET) surface area of WPAC increased, and the average pore radius of WPAC decreased, as water feed rate and activation time increased. In this study, a conventional direct impregnation process was used to prepare the sulfurized PAC by impregnating WPAC with sodium sulfide (Na2S) solution. Furthermore, an innovative compositive impregnation process was developed and then compared with the conventional direct impregnation process. Experimental results showed that the compositive impregnation process produced the sulfurized WPAC with high BET surface area and a high S content. A maximum BET surface area of 886 m2/g and the S content of 2.61% by mass were obtained at 900 degrees C and at the S feed ratio of 2160 mg Na2S/g C. However, the direct impregnation process led to a BET surface area of sulfurized WPAC that decreased significantly as the S content increased.

  5. Phase, morphology, and dimension control of CIS powders prepared using a solvothermal process

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Chih-Hui [Department of Materials Science and Engineering, National Cheng Kung University, Tainan, Taiwan (China); Ting, Jyh-Ming, E-mail: jting@mail.ncku.edu.t [Department of Materials Science and Engineering, National Cheng Kung University, Tainan, Taiwan (China)

    2009-05-29

    Crystalline chalcopyrite semiconductor CuInSe{sub 2} nanostructures were prepared using a solvothermal route. Various amine organic agents were used as the solvents. Cupric chloride, indium chloride, and selenium powders were mixed in a solvent of ethylenediamine or diethylamine. Effects of reaction time, reaction temperature, solvent type, and reactant concentration were studied. The results show that through selective processing conditions, the phase, morphology, and dimensions of the obtained CIS nanostructures can be controlled.

  6. A simple and highly effective process for the preparation of activated carbons with high surface area

    Energy Technology Data Exchange (ETDEWEB)

    Li Ying, E-mail: liyingjlu@163.com [College of Chemistry, Jilin University, Changchun 130012 (China); Ding Xuefeng; Guo Yupeng; Wang Lili; Rong Chunguang; Qu Yuning; Ma Xiaoyu [College of Chemistry, Jilin University, Changchun 130012 (China); Wang Zichen, E-mail: wangzc@jlu.edu.cn [College of Chemistry, Jilin University, Changchun 130012 (China)

    2011-06-15

    Highlights: {yields} High surface area activated carbon can be prepared by rice husk H{sub 3}PO{sub 4} without pretreatment. {yields} The characteristics of the activated carbon were greatly influenced by post-processing method. {yields} The lower SiO{sub 2} content of the activated carbons, the higher pore volume the carbons had. {yields} Some silica in rice husk reacted with H{sub 3}PO{sub 4} to form SiP{sub 2}O{sub 7} which could be removed by post-process. - Abstract: Activated carbons with high surface area were prepared by phosphoric acid as activation agent and rice husks as precursors. It was found that the characteristics of the activated carbons were influenced not only by the preparation but also by the post-processing method. The high surface area of the activated carbons was prepared under the optimum condition (50% H{sub 3}PO{sub 4} with impregnation ratio of 5:1, activation temperature of 500 deg. C, activation time of 0.5 h, wash water temperature of 100 deg. C). SiO{sub 2} content could affect the surface area of activated carbons, either. The lower SiO{sub 2} content of the activated carbons, the higher pore volume the carbons had. The SiO{sub 2} content was 11.2% when used the optimum condition. The explanation was that silicon element in rice husks reacted with H{sub 3}PO{sub 4} to form silicon phosphate (SiP{sub 2}O{sub 7}), and it could be proved further by X-ray diffraction analysis, SiP{sub 2}O{sub 7} could be removed by post-process.

  7. Iron Oxide Films Prepared by Rapid Thermal Processing for Solar Energy Conversion

    DEFF Research Database (Denmark)

    Wickman, B.; da Silva Fanta, Alice Bastos; Burrows, Andrew

    2017-01-01

    considerably. Herein, we present hematite thin films fabricated via one-step oxidation of Fe by rapid thermal processing (RTP). In particular, we investigate the effect of oxidation temperature on the PEC properties of hematite. Films prepared at 750 °C show the highest activity towards water oxidation......, potentially also on nanostructured electrodes, where retaining high surface area is crucial to maximize performance....

  8. Processes for preparing carbon fibers using sulfur trioxide in a halogenated solvent

    Energy Technology Data Exchange (ETDEWEB)

    Patton, Jasson T.; Barton, Bryan E.; Bernius, Mark T.; Chen, Xiaoyun; Hukkanen, Eric J.; Rhoton, Christina A.; Lysenko, Zenon

    2015-12-29

    Disclosed here are processes for preparing carbonized polymers (preferably carbon fibers), comprising sulfonating a polymer with a sulfonating agent that comprises SO.sub.3 dissolved in a solvent to form a sulfonated polymer; treating the sulfonated polymer with a heated solvent, wherein the temperature of the solvent is at least 95.degree. C.; and carbonizing the resulting product by heating it to a temperature of 500-3000.degree. C. Carbon fibers made according to these methods are also disclosed herein.

  9. Microstructural Evolution of Semisolid 6063 Aluminum Alloy Prepared by Recrystallization and Partial Melting Process

    Science.gov (United States)

    Wang, Yongfei; Zhao, Shengdun; Zhang, Chenyang

    2017-08-01

    Radial forging (RF) was proposed as a novel deformation method to prepare semisolid 6063 aluminum alloy in the recrystallization and partial melting (RAP) process. The effects of area reduction rate, isothermal holding temperature and time on the microstructural evolution of RF-deformed 6063 aluminum alloy were investigated. Results showed that RF can be successfully introduced in RAP process to prepare large semisolid 6063 aluminum alloy bar. With the increase of the area reduction rate, the average grain size firstly decreased and then no significant change occurred. Meanwhile, the spheroidization degree of solid grains firstly increased rapidly, and then increased slowly. The effects of isothermal holding temperature and time are similar, with the increase of the isothermal holding temperature or time, the average grain size initially decreased but then increased; and the spheroidization degree of solid grains gradually increased. High-quality semisolid 6063 aluminum alloy can be prepared with 70% area reduction rate and subsequent semisolid isothermal treatment (SSIT) at 630 °C for 10 min. The coarsening rate constant was 5185.2 µm3/s at 630 °C. Additionally, a strong deformation texture was created in the RF-deformed alloy with 70% area reduction rate, which was transformed to a weakened texture following the SSIT process.

  10. 制药工艺用水制备流程分析%Pharmaceutical preparation process water process analysis

    Institute of Scientific and Technical Information of China (English)

    闫秀红

    2015-01-01

    Preparation process of pharmaceutical process water include purified water treatment and water purification. At present, China's pharmaceutical unit structure and function of the presence of water equipment defective design, device control parameters are not advanced, pharmaceutical water equipment design and manufacturing level and low. Should increase supportive technology and funds to update equipment and systems, establish a sound regulatory system to address the pharmaceutical preparation process water problems.%制药工艺用水的制备流程包括水的提纯处理和水的纯化。目前我国制药用水设备存在装置结构功能设计不完善、设备控制参数不先进、制药用水设备设计及制造水平低等问题。应加大技术和资金的支持力,及时更新设备和系统,建立健全监管制度,以解决制药用水制备过程中出现的问题。

  11. Oral Rinse as a Simpler Approach to Exfoliative Cytology: A Comparative Study

    OpenAIRE

    Mulki, Shaila; Shetty, Pushparaj; Pai, Prakash

    2013-01-01

    Background: Oral rinse is a novel method that can be used to detect dysplasia in potentially malignant disorders and malignant oral lesions in resource challenged areas. A study was undertaken to compare the quality of the normal smears prepared with the oral rinse and that of the wooden tongue spatula.

  12. LOTUS— Preparing Sentinel-3 SAR Altimetry Processing for Ocean and Land

    DEFF Research Database (Denmark)

    Knudsen, Per; Andersen, Ole Baltazar; Nielsen, Karina

    methods and processing chains need to be developed. Subsequently, new potential Copernicus products should be developed that utilize the improved along-track resolution over both the oceans and over land. The main objective of the LOTUS project is to prepare the scientific and operational use of data from...... Sentinels 3. Then new operational processing, validation and delivery mechanisms need to be developed and implemented for generating the new dynamic products. Finally, the take-up of the new Copernicus products by the value-adding sectors needs to be stimulated and demonstrated to ensure...

  13. LOTUS— Preparing Sentinel-3 SAR Altimetry Processing for Ocean and Land

    DEFF Research Database (Denmark)

    Knudsen, Per; Andersen, Ole Baltazar; Nielsen, Karina

    2016-01-01

    methods and processing chains need to be developed. Subsequently, new potential Copernicus products should be developed that utilize the improved alongtrack resolution over both the oceans and over land. The main objective of the LOTUS project is to prepare the scientific and operational use of data from...... Sentinels 3. Then new operational processing, validation and delivery mechanisms need to be developed and implemented for generating the new dynamic products. Finally, the take-up of the new Copernicus products by the value-adding sectors needs to be stimulated and demonstrated to ensure...

  14. Hanford Waste Vitrification Plant full-scale feed preparation testing with water and process simulant slurries

    Energy Technology Data Exchange (ETDEWEB)

    Gaskill, J.R.; Larson, D.E.; Abrigo, G.P. [and others

    1996-03-01

    The Hanford Waste Vitrification Plant was intended to convert selected, pretreated defense high-level waste and transuranic waste from the Hanford Site into a borosilicate glass. A full-scale testing program was conducted with nonradioactive waste simulants to develop information for process and equipment design of the feed-preparation system. The equipment systems tested included the Slurry Receipt and Adjustment Tank, Slurry Mix Evaporator, and Melter-Feed Tank. The areas of data generation included heat transfer (boiling, heating, and cooling), slurry mixing, slurry pumping and transport, slurry sampling, and process chemistry. 13 refs., 129 figs., 68 tabs.

  15. ON DEVELOPMENT OF OPTIMAL METALLURGICAL PROCESS FOR PREPARATION OF A NEW GENERATION OF INTERMETALLIC ALLOYS

    Directory of Open Access Journals (Sweden)

    Viliam Hrnčiar

    2009-06-01

    Full Text Available Intermetallic TiAl based alloys are used in extreme conditions, e.g. high temperature, aggressive atmosphere and combined high temperature mechanical loading. The contribution deals with development and optimization of plasma melting metallurgical process in new developed crystallizer with rotational and axial movement of melt, for preparation of new intermetallic alloys based on Ti-(45-48Al-(1-10Ta (at.%. The melting process parameters and their influence to final microstructure and properties of alloys are discussed. The aim of this work is to produce alloys with lower number of technological steps necessary to achieve chemical composition, homogeneity and purity as well.

  16. Detection of Acetone Processing of Castor Bean Mash for Forensic Investigation of Ricin Preparation Methods

    Energy Technology Data Exchange (ETDEWEB)

    Kreuzer-Martin, Helen W.; Wahl, Jon H.; Metoyer, Candace N.; Colburn, Heather A.; Wahl, Karen L.

    2010-07-01

    The toxic protein ricin is of concern as a potential biological threat agent (BTA) Recently, several samples of ricin have been seized in connection with biocriminal activity. Analytical methods are needed that enable federal investigators to determine how the samples were prepared, to match seized samples to potential source materials, and to identify samples that may have been prepared by the same method using the same source materials. One commonly described crude ricin preparation method is acetone extraction of crushed castor beans. Here we describe the use of solid-phase microextraction and headspace analysis of crude ricin preparation samples to determine whether they were processed by acetone extraction. In all cases, acetone-extracted bean mash could be distinguished from un-extracted mash or mash extracted with other organic solvents. Statistical analysis showed that storage in closed containers for up to 109 days had no effect on acetone signal intensity. Signal intensity in acetone-extracted mash decreased during storage in open containers, but extracted mash could still be distinguished from un-extracted mash after 94 days.

  17. Standard manufacturing process of Makaradhwaja prepared by Swarna Patra - Varkha and Bhasma.

    Science.gov (United States)

    Khedekar, Sanjay; Patgiri, B J; Ravishankar, B; Prajapati, P K

    2011-01-01

    Makaradhwaja is an important Kupipakwa Rasayana. It is prepared by using Swarna (gold), Parada (mercury) and Gandhaka (sulfur) in different ratios, i.e. 1:8:16, 1:8:24 and 1:2:4, respectively. The amount of Gandhaka in the Jarana process is directly proportional to the increase in therapeutic efficacy and reduces the toxicity of the product. Specific temperature pattern for the preparation of Makaradhwaja has been followed. In the present study Swarna, Parada and Gandhaka were taken in the ratio 1:8:24, respectively, and 12 h of heating for a specified amount of Kajjali (i.e., 400 g) in a Kacha Kupi 1/3(rd) of its capacity. There are some controversies regarding the form of Swarna (i.e., Swarna Patra Swarna Varkha or Swarna Bhasma) used in the preparation of Makaradhwaja. Therefore, in the present study, the samples of Makaradhwaja were prepared by Swarna Patra, Varkha and Bhasma in different batches. It was found that the use of Varkha produced a good-quality product along with the maximum amount of gold, i.e. 268 ppm, in comparison with Patra, i.e. 131 ppm, and Bhasma, i.e. 19 ppm, respectively.

  18. Standard manufacturing process of Makaradhwaja prepared by Swarna Patra – Varkha and Bhasma

    Science.gov (United States)

    Khedekar, Sanjay; Patgiri, B. J.; Ravishankar, B.; Prajapati, P. K.

    2011-01-01

    Makaradhwaja is an important Kupipakwa Rasayana. It is prepared by using Swarna (gold), Parada (mercury) and Gandhaka (sulfur) in different ratios, i.e. 1:8:16, 1:8:24 and 1:2:4, respectively. The amount of Gandhaka in the Jarana process is directly proportional to the increase in therapeutic efficacy and reduces the toxicity of the product. Specific temperature pattern for the preparation of Makaradhwaja has been followed. In the present study Swarna, Parada and Gandhaka were taken in the ratio 1:8:24, respectively, and 12 h of heating for a specified amount of Kajjali (i.e., 400 g) in a Kacha Kupi 1/3rd of its capacity. There are some controversies regarding the form of Swarna (i.e., Swarna Patra Swarna Varkha or Swarna Bhasma) used in the preparation of Makaradhwaja. Therefore, in the present study, the samples of Makaradhwaja were prepared by Swarna Patra, Varkha and Bhasma in different batches. It was found that the use of Varkha produced a good-quality product along with the maximum amount of gold, i.e. 268 ppm, in comparison with Patra, i.e. 131 ppm, and Bhasma, i.e. 19 ppm, respectively. PMID:22131768

  19. Semi-solid A356 alloy slurry for rheocasting prepared by a new process

    Directory of Open Access Journals (Sweden)

    Liu Zheng

    2013-05-01

    Full Text Available To obtain the semi-solid slurry with uniform and fine structure morphology that satisfies the requirement of rheocasting process, a new process for preparing semi-solid Al alloy slurry was developed, in which local chilling was combined with low superheat pouring and slight electromagnetic stirring (LSPSEMS. The morphology and the size of primary α-Al in the A356 alloy slurry prepared with the new process, i.e., LSPSEMS with local chilling, were investigated using MIAPS image analyzing software, and the grain refinement mechanism was discussed. The results indicate that the semi-solid primary phase consists of particle-like or globular-like α-Al, and the morphology and grain size of primary α-Al in the slurry can be markedly improved by the new process. The fine primary α-Al distributes uniformly in the slurry, which satisfies the requirement of rheocasting. Compared with the alloy prepared by LSPSEMS, the average equal-area-circle grain diameter of primary α-Al in semi-solid A356 alloy ingot prepared by the new process is decreased from 85.6 μm to 68.8 μm at the central area, 112.6 μm to 77.6 μm at the transition area and is 84.7 μm in the edge area, respectively. The corresponding shape factor of primary α-Al is increased from 0.78 to 0.83, 0.54 to 0.77 and 0.28 to 0.59, respectively. In addition, the pouring temperature could be suitably raised from 620-630 ℃ of the traditional process to 650 ℃ using this technique, which is convenient for practical operation. The mechanism of grain refinement, in the new process, is that the local chilling quickens up the temperature decrease in the center of the melt. The nuclei could not grow up in a short time so the finer grains are formed in the melt.

  20. Preparation and pharmaceutical characterization of amorphous cefdinir using spray-drying and SAS-process.

    Science.gov (United States)

    Park, Junsung; Park, Hee Jun; Cho, Wonkyung; Cha, Kwang-Ho; Kang, Young-Shin; Hwang, Sung-Joo

    2010-08-30

    The aim of this study was to investigate the effects of micronization and amorphorization of cefdinir on solubility and dissolution rate. The amorphous samples were prepared by spray-drying (SD) and supercritical anti-solvent (SAS) process, respectively and their amorphous natures were confirmed by DSC, PXRD and FT-IR. Thermal gravimetric analysis was performed by TGA. SEM was used to investigate the morphology of particles and the processed particle had a spherical shape, while the unprocessed crystalline particle had a needle-like shape. The mean particle size and specific surface area were measured by dynamic light scattering (DLS) and BET, respectively. The DLS result showed that the SAS-processed particle was the smallest, followed by SD and the unprocessed cefdinir. The BET result was the same as DLS result in that the SAS-processed particle had the largest surface area. Therefore, the processed cefdinir, especially the SAS-processed particle, appeared to have enhanced apparent solubility, improved intrinsic dissolution rate and better drug release when compared with SD-processed and unprocessed crystalline cefdinir due not only to its amorphous nature, but also its reduced particle size. Conclusions were that the solubility and dissolution rate of crystalline cefdinir could be improved by physically modifying the particles using SD and SAS-process. Furthermore, SAS-process was a powerful methodology for improving the solubility and dissolution rate of cefdinir.

  1. [Improvement of medical processes with Six Sigma - practicable zero-defect quality in preparation for surgery].

    Science.gov (United States)

    Sobottka, Stephan B; Töpfer, Armin; Eberlein-Gonska, Maria; Schackert, Gabriele; Albrecht, D Michael

    2010-01-01

    Six Sigma is an innovative management- approach to reach practicable zero- defect quality in medical service processes. The Six Sigma principle utilizes strategies, which are based on quantitative measurements and which seek to optimize processes, limit deviations or dispersion from the target process. Hence, Six Sigma aims to eliminate errors or quality problems of all kinds. A pilot project to optimize the preparation for neurosurgery could now show that the Six Sigma method enhanced patient safety in medical care, while at the same time disturbances in the hospital processes and failure costs could be avoided. All six defined safety relevant quality indicators were significantly improved by changes in the workflow by using a standardized process- and patient- oriented approach. Certain defined quality standards such as a 100% complete surgical preparation at start of surgery and the required initial contact of the surgeon with the patient/ surgical record on the eve of surgery could be fulfilled within the range of practical zero- defect quality. Likewise, the degree of completion of the surgical record by 4 p.m. on the eve of surgery and their quality could be improved by a factor of 170 and 16, respectively, at sigma values of 4.43 and 4.38. The other two safety quality indicators "non-communicated changes in the OR- schedule" and the "completeness of the OR- schedule by 12:30 a.m. on the day before surgery" also show an impressive improvement by a factor of 2.8 and 7.7, respectively, corresponding with sigma values of 3.34 and 3.51. The results of this pilot project demonstrate that the Six Sigma method is eminently suitable for improving quality of medical processes. In our experience this methodology is suitable, even for complex clinical processes with a variety of stakeholders. In particular, in processes in which patient safety plays a key role, the objective of achieving a zero- defect quality is reasonable and should definitely be aspirated.

  2. Oral rinse as a simpler approach to exfoliative cytology: a comparative study.

    Science.gov (United States)

    Mulki, Shaila; Shetty, Pushparaj; Pai, Prakash

    2013-12-01

    Oral rinse is a novel method that can be used to detect dysplasia in potentially malignant disorders and malignant oral lesions in resource challenged areas. A study was undertaken to compare the quality of the normal smears prepared with the oral rinse and that of the wooden tongue spatula. One hundred five normal subjects were selected for the study. Two smears were prepared from clinically normal mucosa using an oral rinse and further two smears were scraped from clinically normal buccal mucosa using a wooden spatula. The smears were graded for cell yield, dispersion and cellular clarity on a three-point scale by two observers. The results were analyzed using Mann Whitney non parametric test. The Oral rinse was found to be significantly more efficient than the wooden spatula, in terms of cell yield (pexfoliative cytology of normal oral mucosa.

  3. Differential preparation intervals modulate repetition processes in task switching: an ERP study

    Directory of Open Access Journals (Sweden)

    Min eWang

    2016-02-01

    Full Text Available In task-switching paradigms, reaction times (RTs switch cost (SC and the neural correlates underlying the SC are affected by different preparation intervals. However, little is known about the effect of the preparation interval on the repetition processes in task-switching. To examine this effect we utilized a cued task-switching paradigm with long sequences of repeated trials. Response-stimulus intervals (RSI and cue-stimulus intervals (CSI were manipulated in short and long conditions. Electroencephalography (EEG and behavioral data were recorded. We found that with increasing repetitions, RTs were faster in the short CSI conditions, while P3 amplitudes decreased in the LS (long RSI and short CSI conditions. Positive correlations between RT benefit and P3 activation decrease (repeat 1 minus repeat 5, and between the slope of the RT and P3 regression lines were observed only in the LS condition. Our findings suggest that differential preparation intervals modulate repetition processes in task switching.

  4. Comparison of reduction disintegration characteristics of TiO2-rich burdens prepared with sintering process and composite agglomeration process

    Science.gov (United States)

    Yu, Zheng-wei; Li, Guang-hui; Liu, Chen; Zhou, Feng; Peng, Zhi-wei; Jiang, Tao

    2016-04-01

    To reveal the impact of the composite agglomeration process (CAP) on the reduction disintegration properties of TiO2-rich ironmaking burden for a blast furnace, the reduction disintegration indices (RDIs), mineral constituents, and microstructure of the products prepared by the CAP and the traditional sintering process (TSP) were investigated. The results showed that, compared to the sinter with a basicity of 2.0 prepared by the TSP, the RDI+6.3 and the RDI+3.15 of the CAP product with the same basicity increased by 28.2wt% and 13.7wt%, respectively, whereas the RDI-0.5 decreased by 2.7wt%. The analysis of the mineral constituents and microstructure of the products indicated that the decreasing titanohematite content decreased the volume expansion during reduction. Meanwhile, the decreasing perovskite content decreased its detrimental effect on the reduction disintegration properties. In addition, the higher silicoferrite of calcium and aluminum (SFCA) content improved the strength of the CAP product. Together, these factors result in an improvement of the RDI of the CAP products. In addition, compared to the sinter, the reduced CAP products clearly contained fewer cracks, which also led to mitigation of reduction disintegration.

  5. Comparison of reduction disintegration characteristics of TiO2-rich burdens prepared with sintering process and composite agglomeration process

    Institute of Scientific and Technical Information of China (English)

    Zheng-wei Yu; Guang-hui Li; Chen Liu; Feng Zhou; Zhi-wei Peng; Tao Jiang

    2016-01-01

    To reveal the impact of the composite agglomeration process (CAP) on the reduction disintegration properties of TiO2-rich iron-making burden for a blast furnace, the reduction disintegration indices (RDIs), mineral constituents, and microstructure of the products pre-pared by the CAP and the traditional sintering process (TSP) were investigated. The results showed that, compared to the sinter with a ba-sicity of 2.0 prepared by the TSP, the RDI+6.3 and the RDI+3.15 of the CAP product with the same basicity increased by 28.2wt%and 13.7wt%, respectively, whereas the RDI−0.5 decreased by 2.7wt%. The analysis of the mineral constituents and microstructure of the products indicated that the decreasing titanohematite content decreased the volume expansion during reduction. Meanwhile, the decreasing perovskite content decreased its detrimental effect on the reduction disintegration properties. In addition, the higher silicoferrite of calcium and aluminum (SFCA) content improved the strength of the CAP product. Together, these factors result in an improvement of the RDI of the CAP products. In addition, compared to the sinter, the reduced CAP products clearly contained fewer cracks, which also led to mitigation of reduction disintegration.

  6. Impacting student anxiety for the USMLE Step 1 through process-oriented preparation

    Directory of Open Access Journals (Sweden)

    Roy E. Strowd

    2010-02-01

    Full Text Available Background: Standardized examinations are the key components of medical education. The USMLE Step 1 is the first of these important milestones. Success on this examination requires both content competency and efficient strategies for study and review. Students employ a wide variety of techniques in studying for this examination, with heavy reliance on personal study habits and advice from other students. Nevertheless, few medical curricula formally address these strategies. Methods: In response to student-generated critique at our institution, a five-part seminar series on process-oriented preparation was developed and implemented to address such concerns. The series focused on early guidance and preparation strategies for Step 1 and the many other important challenges in medical school. Emphasis was placed on facilitating conversation and mentorship opportunities between students. Results & Conclusions: A profoundly positive experience was reported by our medical students that included a decreased anxiety level for the Step 1 examination.

  7. Zinc-oxide-based sorbents and processes for preparing and using same

    Science.gov (United States)

    Gangwal, Santosh Kumar; Turk, Brian Scott; Gupta, Raghubir Prasael

    2010-03-23

    Zinc oxide-based sorbents, and processes for preparing and using them are provided. The sorbents are preferably used to remove one or more reduced sulfur species from gas streams. The sorbents comprise an active zinc component, optionally in combination with one or more promoter components and/or one or more substantially inert components. The active zinc component is a two phase material, consisting essentially of a zinc oxide (ZnO) phase and a zinc aluminate (ZnAl.sub.2O.sub.4) phase. Each of the two phases is characterized by a relatively small crystallite size of typically less than about 500 Angstroms. Preferably the sorbents are prepared by converting a precursor mixture, comprising a precipitated zinc oxide precursor and a precipitated aluminum oxide precursor, to the two-phase, active zinc oxide containing component.

  8. Preparation and properties of the magnetic absorbent polymer via the chemical transformation process

    Science.gov (United States)

    Liu, Shengyu; Zhang, Suhong; Guo, Jianying; Wen, Jing; Qiao, Yan

    2017-01-01

    Magnetic polyacrylic acid sodium polymer (MPAAS) was prepared by chemical transformation method. Key parameters were investigated in the synthesis process of the magnetic polymer and an optimum preparation condition was gained. The structure of the magnetic polymer was characterized by X-ray diffraction (XRD), Fourier transform infrared spectrosocopy (FTIR) and scanning electron microscope (SEM). Magnetic property of the magnetic polymer was measured by the magnet and superconducting quantum interference device (SQUID). Both the swelling ratio and kinetics and the water retention ratio and kinetics were investigated. Based on the results, it can be gained that both swelling rate and equilibrium swelling rate were lowered after magnetization while the water retention ability of the magnetic polymer is stronger than that of the polymer.

  9. Processing surface sizing starch using oxidation, enzymatic hydrolysis and ultrasonic treatment methods--Preparation and application.

    Science.gov (United States)

    Brenner, Tobias; Kiessler, Birgit; Radosta, Sylvia; Arndt, Tiemo

    2016-03-15

    The surface application of starch is a well-established method for increasing paper strength. In surface sizing, a solution of degraded starch is applied to the paper. Two procedures have proved valuable for starch degradation in the paper mill: enzymatic and thermo-oxidative degradation. The objective of this study was to determine achievable efficiencies of cavitation in preparing degraded starch for surface application on paper. It was found that ultrasonic-assisted starch degradation can provide a starch solution that is suitable for surface sizing. The molecular composition of starch solutions prepared by ultrasonic treatment differed from that of starch solutions degraded by enzymes or by thermo-oxidation. Compared to commercial degradation processes, this resulted in intensified film formation and in greater penetration during surface sizing and ultimately in a higher starch content of the paper. Paper sized with ultrasonically treated starch solutions show the same strength properties compared to commercially sized paper.

  10. A novel green nonaqueous sol-gel process for preparation of partially stabilized zirconia nanopowder

    Directory of Open Access Journals (Sweden)

    Guo Feng

    2017-09-01

    Full Text Available A novel green nonaqueous sol-gel process was developed to prepare 3 mol% Y2O3-doped ZrO2 nanopowder from zirconium oxychloride and without need for washing of the obtained particles. It was shown that highly dispersive nanometer-scale zirconia powder with the particle size of 15–25 nm and BET surface area of 41.2 m2/g can be prepared. The sintering behaviour was also investigated. Density of the translucent body sintered at 1400 °C is 98.7 ± 0.3% of its theoretical density and the surface and cross section areas are dense without holes or other defects. The bending strength of the sintered sample is 928 ± 64 MPa.

  11. Enhanced bioavailability of sirolimus via preparation of solid dispersion nanoparticles using a supercritical antisolvent process

    Directory of Open Access Journals (Sweden)

    Kim MS

    2011-11-01

    Full Text Available Min-Soo Kim1, Jeong-Soo Kim1, Hee Jun Park1, Won Kyung Cho1,3, Kwang-Ho Cha1,3, Sung-Joo Hwang2,31College of Pharmacy, Chungnam National University, Daejeon, Republic of Korea, 2College of Pharmacy, 3Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, Republic of KoreaBackground: The aim of this study was to improve the physicochemical properties and bioavailability of poorly water-soluble sirolimus via preparation of a solid dispersion of nanoparticles using a supercritical antisolvent (SAS process.Methods: First, excipients for enhancing the stability and solubility of sirolimus were screened. Second, using the SAS process, solid dispersions of sirolimus-polyvinylpyrrolidone (PVP K30 nanoparticles were prepared with or without surfactants such as sodium lauryl sulfate (SLS, tocopheryl propylene glycol succinate, Sucroester 15, Gelucire 50/13, and Myrj 52. A mean particle size of approximately 250 nm was obtained for PVP K30-sirolimus nanoparticles. Solid state characterization, kinetic solubility, powder dissolution, stability, and pharmacokinetics were analyzed in rats.Results: X-ray diffraction, differential scanning calorimetry, and high-pressure liquid chromatography indicated that sirolimus existed in an anhydrous amorphous form within a solid dispersion of nanoparticles and that no degradation occurred after SAS processing. The improved supersaturation and dissolution of sirolimus as a solid dispersion of nanoparticles appeared to be well correlated with enhanced bioavailability of oral sirolimus in rats. With oral administration of a solid dispersion of PVP K30-SLS-sirolimus nanoparticles, the peak concentration and AUC0→12h of sirolimus were increased by approximately 18.3-fold and 15.2-fold, respectively.Conclusion: The results of this study suggest that preparation of PVP K30-sirolimus-surfactant nanoparticles using the SAS process may be a promising approach for improving the bioavailability of sirolimus

  12. Preparative chromatography with supercritical fluids. Comparison of simulated moving bed and batch processes.

    Science.gov (United States)

    Peper, Stephanie; Johannsen, Monika; Brunner, Gerd

    2007-12-28

    Preparative chromatography is a key technology for the separation of fine chemicals in production scale. Most of the published studies are carried out using liquid solvents as mobile phase. However, the used organic solvents can often be replaced by supercritical fluids. A reduction or renouncement of organic solvents does not only correspond to the trend of the so-called green chemistry--a sustainable, environmentally friendly production of chemical products. But a changeover to chromatography with supercritical fluids can also be reasonable under economic criteria. In this contribution a comparison between the Batch-supercritical fluid chromatography (Batch-SFC) process and the simulated moving bed (SMB)-SFC process is presented. Because of the minor importance of solvent consumption and solvent recovery in SFC, the separation systems were optimized primarily in terms of their specific productivity. For three of the four investigated model systems, the specific productivity of the SMB process is significantly higher than the productivity of the Batch process. Due to the fact, that the process with the higher specific productivity is not inevitably the more economical process, supplementary the costs of the process were considered. Therefore the comparison of the two processes was done from an economic point of view considering the minimum product price that has to be realized to fulfill the defined economic aim. It was found that although the optimized specific productivities of the SMB process were significantly higher than the productivities of the Batch process, the Batch process is the more profitable process for the investigated production rate range between 0.4 and 5t/a.

  13. [Discussion on research and development of new traditional Chinese medicine preparation process based on idea of QbD].

    Science.gov (United States)

    Feng, Yi; Hong, Yan-Long; Xian, Jie-Chen; Du, Ruo-Fei; Zhao, Li-Jie; Shen, Lan

    2014-09-01

    Traditional processes are mostly adopted in traditional Chinese medicine (TCM) preparation production and the quality of products is mostly controlled by terminal. Potential problems of the production in the process are unpredictable and is relied on experience in most cases. Therefore, it is hard to find the key points affecting the preparation process and quality control. A pattern of research and development of traditional Chinese medicine preparation process based on the idea of Quality by Design (QbD) was proposed after introducing the latest research achievement. Basic theories of micromeritics and rheology were used to characterize the physical property of TCM raw material. TCM preparation process was designed in a more scientific and rational way by studying the correlation among enhancing physical property of raw material, preparation process and product quality of preparation. So factors affecting the quality of TCM production would be found out and problems that might occur in the pilot process could be predicted. It would be a foundation for the R&D and production of TCM preparation as well as support for the "process control" of TCMIs gradually realized in the future.

  14. New process for preparing complex-shaped dielectric film similar to Mylar

    Science.gov (United States)

    Lagasse, R. R.; Kraynik, A. M.

    1982-02-01

    A new thermoforming/heat-treatment process yields complex-shaped dielectric film having electrical and shrinkage properties similar to those of flat Mylar film. This similarity should extend to other physical properties because the new process is directly analogous to the process used to prepare Mylar. Commercially available poly(ethylene terephthalate) film is formed into a cavity at approx. 110 C and then heat treated at approx. 180 C. A laboratory-scale forming apparatus has produced cylindrically shaped films having depth/diameter ratio approx. 1, a tapered wall-section, and variation in wall thickness of 3X. Evaluation of other forming methods suggest that the production rate and thickness uniformity can be improved with existing technology. Thermal shrinkage at 150 C, 1 kHz dielectric constant from -55 to +70 C, leakage current at 1 kV, and breakdown voltage have been measured for both the complex-shaped film and Mylar.

  15. Iron Oxide Films Prepared by Rapid Thermal Processing for Solar Energy Conversion

    Science.gov (United States)

    Wickman, B.; Bastos Fanta, A.; Burrows, A.; Hellman, A.; Wagner, J. B.; Iandolo, B.

    2017-01-01

    Hematite is a promising and extensively investigated material for various photoelectrochemical (PEC) processes for energy conversion and storage, in particular for oxidation reactions. Thermal treatments during synthesis of hematite are found to affect the performance of hematite electrodes considerably. Herein, we present hematite thin films fabricated via one-step oxidation of Fe by rapid thermal processing (RTP). In particular, we investigate the effect of oxidation temperature on the PEC properties of hematite. Films prepared at 750 °C show the highest activity towards water oxidation. These films show the largest average grain size and the highest charge carrier density, as determined from electron microscopy and impedance spectroscopy analysis. We believe that the fast processing enabled by RTP makes this technique a preferred method for investigation of novel materials and architectures, potentially also on nanostructured electrodes, where retaining high surface area is crucial to maximize performance. PMID:28091573

  16. Study of Al composites prepared by high-energy ball milling; Effect of processing conditions

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza-Duarte, J.M.; Estrada-Guel, I.; Carreño-Gallardo, C.; Martínez-Sánchez, R.

    2015-09-15

    The present work deals with the synthesis of some Al-based composites prepared by mechanical milling and processing by powder metallurgy followed by the evaluation of process conditions as: type of additive, their concentration and milling intensity studying its effect on the characteristics of the powder composite and mechanical performance of the composite. Powder samples were microstructural characterized by electronic microscopy (SEM–TEM) and the mechanical response was followed by hardness and compressive tests. A pronounced effect on the mechanical response of the specimens was evident after the addition of reinforced particles and milling intensity. Microscopy studies showed a uniform dispersion of the reinforcing particles in the metallic matrix at nanometric scale and an important grain refinement of the Al matrix was confirmed. After processing, a 66% increase on the mechanical response was reached with 1% of additive complemented with short milling intensities.

  17. Iron Oxide Films Prepared by Rapid Thermal Processing for Solar Energy Conversion

    Science.gov (United States)

    Wickman, B.; Bastos Fanta, A.; Burrows, A.; Hellman, A.; Wagner, J. B.; Iandolo, B.

    2017-01-01

    Hematite is a promising and extensively investigated material for various photoelectrochemical (PEC) processes for energy conversion and storage, in particular for oxidation reactions. Thermal treatments during synthesis of hematite are found to affect the performance of hematite electrodes considerably. Herein, we present hematite thin films fabricated via one-step oxidation of Fe by rapid thermal processing (RTP). In particular, we investigate the effect of oxidation temperature on the PEC properties of hematite. Films prepared at 750 °C show the highest activity towards water oxidation. These films show the largest average grain size and the highest charge carrier density, as determined from electron microscopy and impedance spectroscopy analysis. We believe that the fast processing enabled by RTP makes this technique a preferred method for investigation of novel materials and architectures, potentially also on nanostructured electrodes, where retaining high surface area is crucial to maximize performance.

  18. Preparation of ITO nano-powders by hydrothermal-calcining process

    Institute of Scientific and Technical Information of China (English)

    GU Ying-ying; QIN Li-ping; LIU Xue-ying

    2006-01-01

    Sn-doped In2O3 (ITO) nano-powders were prepared by hydrothermal-calcining process. Using SnCl4·5H2O and In as starting materials, the crystallites were characterized by XRD, TEM and BET. The effects of the conditions on the product were investigated. The results show that the phase of hydrothermal precursor obtained by hydrothermal process is related to the temperature of hydrothermal reaction, I. E. , the phases are amorphous In(OH)3 in 160 - 180℃; In(OH)3 crystal in 200℃ and (In1-xSnx)OOH crystal in 200 - 300℃. ITO nano-powders with hexagonal structure and average size of 65 nm are obtained by calcining the precursor derived from the hydrothermal process at 350 - 650℃. The BET of ITO crystal can reach 84. 023 4 m2·g-1.

  19. EFFECTS OF THE PULP PREPARATION AND PAPERMAKING PROCESSES ON THE PROPERTIES of OCC FIBERS

    Directory of Open Access Journals (Sweden)

    Jinquan Wan

    2011-03-01

    Full Text Available Changes of the pore structure of recycled fibers and the strength properties of papers produced by old corrugated container (OCC recycled fibers were studied, after they were subjected to different stock preparation and papermaking processes. In this paper, the effects of beating, sizing, pressing, and drying on fiber properties were investigated, and the porous structure of fibers was analyzed by nitrogen adsorption technique. The results showed that beating, pressing, and other physical processes significantly influenced the fiber properties, whereas the effects of sizing were minor. Significant changes of water retention value (WRV, crystallinity index, and paper strength were observed after those processes. Further, an effort has been made to show relationships between pore structure and macroscopic properties (WRV, crystallinity index of recycled fibers.

  20. Evaluation of the quality of blood components prepared using the Reveos automated blood processing system.

    Science.gov (United States)

    Johnson, L; Winter, K M; Kwok, M; Reid, S; Marks, D C

    2013-10-01

    The Reveos automated blood processing system has been developed to combine primary and secondary processing of whole-blood units, resulting in a plasma unit, a red-blood-cell concentrate and an interim platelet unit per input. The aim of this study was to determine product specifications and in vitro quality of components produced by the Reveos system. Whole blood was processed using the Reveos system and compared with historical Reference units produced using semi-automated methods. Reveos red cells were leucoreduced and stored in SAGM at 4°C. Reveos plasma was frozen at -30°C and factor activity was assessed after thawing. Reference red cell, plasma and buffy coats were produced by top and bottom processing. Leucoreduced Reveos and Reference platelet concentrates were prepared by pooling four interim platelet units or four buffy coats, respectively, with SSP+. Processing with the Reveos system was faster (76 min) than semi-automated separation (92 min). The red cell and platelet yields were higher in the units prepared by the Reveos system. The Reference and Reveos red cell and plasma units had very similar in vitro quality parameters. The platelet concentrates were also similar in many in vitro parameters, including pH, glucose and lactate metabolism, hypotonic shock response and phosphatidylserine expression, although platelet activation markers (CD62P and cytokine levels) were higher in the Reveos units. The Reveos system can improve blood component efficiencies through reductions in processing time, whilst maintaining similar component quality. Vox Sanguinis © 2013 International Society of Blood Transfusion.

  1. Preparation of silica thin films by novel wet process and study of their optical properties.

    Science.gov (United States)

    Im, Sang-Hyeok; Kim, Nam-Jin; Kim, Dong-Hwan; Hwang, Cha-Won; Yoon, Duck-Ki; Ryu, Bong-Ki

    2012-02-01

    Silicon dioxide (SiO2) thin films have gained considerable attention because of their various industrial applications. For example, SiO2 thin films are used in superhydrophilic self-cleaning surface glass, UV protection films, anti-reflection coatings, and insulating materials. Recently, many processes such as vacuum evaporation, sputtering, chemical vapor deposition, and spin coating have been widely applied to prepare thin films of functionally graded materials. However, these processes suffer from several engineering problems. For example, a special apparatus is required for the deposition of films, and conventional wet processes are not suitable for coating the surfaces of substrates with a large surface area and complex morphology. In this study, we investigated the film morphology and optical properties of SiO2 films prepared by a novel technique, namely, liquid phase deposition (LPD). Images of the SiO2 films were obtained by scanning electron microscopy (SEM) and atomic force microscopy (AFM) in order to study the surface morphology of these films: these images indicate that films deposited with different reaction times were uniform and dense and were composed of pure silica. Optical properties such as refractive index and transmittance were estimated by UV-vis spectroscopy and ellipsometry. SiO2 films with porous structures at the nanometer scale (100-250 nm) were successfully produced by LPD. The deposited film had excellent transmittance in the visible wavelength region.

  2. Characterization and performance assessment of solid dispersions prepared by hot melt extrusion and spray drying process.

    Science.gov (United States)

    Agrawal, Anjali M; Dudhedia, Mayur S; Patel, Ashwinkumar D; Raikes, Michelle S

    2013-11-30

    The present study investigated effect of manufacturing methods such as hot melt extrusion (HME) and spray drying (SD) on physicochemical properties, manufacturability, physical stability and product performance of solid dispersion. Solid dispersions of compound X and PVP VA64 (1:2) when prepared by SD and HME process were amorphous by polarized light microscopy, powder X-ray diffractometry, and modulated differential scanning calorimetry analyses with a single glass transition temperature. Fourier transform infrared (FT-IR) and Raman spectroscopic analyses revealed similar molecular level interactions between compound X and PVP VA64 as evident by overlapping FT-IR and FT Raman spectra in SD and HME solid dispersions. The compactibility, tabletability, disintegration and dissolution performance were similar for solid dispersions prepared by both processing techniques. Differences in material properties such as surface area, morphological structure, powder densities, and flow characteristics were observed between SD and HME solid dispersion. The SD solid dispersion was physically less stable compared to HME solid dispersion under accelerated stability conditions. Findings from this study suggest that similar product performance could be obtained if the molecular properties of the solid dispersion processed by two different techniques are similar. However differences in material properties might affect the physical stability of the solid dispersions.

  3. Near net shape forming processes for chemically prepared zinc oxide varistors.

    Energy Technology Data Exchange (ETDEWEB)

    Lockwood, Steven John; Voigt, James A.; Tuttle, Bruce Andrew; Bell, Nelson Simmons

    2005-01-01

    Chemically prepared zinc oxide powders are fabricated for the production of high aspect ratio varistor components. Colloidal processing in water was performed to reduce agglomerates to primary particles, form a high solids loading slurry, and prevent dopant migration. The milled and dispersed powder exhibited a viscoelastic to elastic behavioral transition at a volume loading of 43-46%. The origin of this transition was studied using acoustic spectroscopy, zeta potential measurements and oscillatory rheology. The phenomenon occurs due to a volume fraction solids dependent reduction in the zeta potential of the solid phase. It is postulated to result from divalent ion binding within the polyelectrolyte dispersant chain, and was mitigated using a polyethylene glycol plasticizing additive. Chemically prepared zinc oxide powders were processed for the production of high aspect ratio varistor components. Near net shape casting methods including slip casting and agarose gelcasting were evaluated for effectiveness in achieving a uniform green microstructure achieving density values near the theoretical maximum during sintering. The structure of the green parts was examined by mercury porisimetry. Agarose gelcasting produced green parts with low solids loading values and did not achieve high fired density. Isopressing the agarose cast parts after drying raised the fired density to greater than 95%, but the parts exhibited catastrophic shorting during electrical testing. Slip casting produced high green density parts, which exhibited high fired density values. The electrical characteristics of slip cast parts are comparable with dry pressed powder compacts. Alternative methods for near net shape forming of ceramic dispersions were investigated for use with the chemically prepared ZnO material. Recommendations for further investigation to achieve a viable production process are presented.

  4. Anomalous variation in the wireless signals propagation associated with earthquake preparation processes

    Science.gov (United States)

    Ouzounov, Dimitar; Velichkova-Yotsova, Sylvia; Pulinets, Sergey

    2016-04-01

    propagation correlated with earthquake preparation processes. Our observations revealed a phenomena associated with the artificially enhancement of the intensity 3.5GHz signals by using WiMax technology (no change in the transmitting level) as a result of electric and electrochemical processes in atmosphere over the regions of ongoing earthquake preparation. To illustrate the nature of such variations in the range of 3.5GHz in relation to earthquake processes we present two case studies: 1/ for M5.8 of May 22, 2012 in Bulgaria and 2/ for M6.9 of May 24, 2014 in Aegean Sea. Concerning the M5.8 of May 22, 2012 the abnormal intensity modulation started on 05.17.2012 (five days in advance) and reached 200% increase. Epicenter of the M5.8 of May 25 was on 15 km from the wireless receiver. Concerning and M6.9 of May 24, 2014 in Aegean Sea abnormal signal was observed on May 22 (two days in advance) with 30% intensity increase. Epicenter of M6.9 of May 24 was at 260 km from the wireless receiver. Most likely the observed increase in the intensity is a direct result of the change in the atmospheric properties in the Atmospheric boundary level (ABL) triggered by intensification of radon and other gases release, which lead to change in lowers atmosphere conductivity, already suggested by Lithosphere-Atmosphere-Ionosphere Coupling concept (Pulinets and Ouzounov, 2011). Another possible reason is the forward scattering of WiMax signal (similar to meteor wakes scattering) on aerosol layers formed over the earthquake preparation zone. We are registering an effect of systematic increase (with different rate) at 3.5 GHz associated with the regional seismicity and no significant intensify modulation with an absence of major seismicity in the region.

  5. Plasmonic photosensitization of polyaniline prepared by a novel process for high-performance flexible photodetector.

    Science.gov (United States)

    Barman, Tapan; Pal, Arup R

    2015-02-01

    We report the synthesis of a polyaniline (PAni)-gold nanoparticle (AuNP) composite thin film in a single step. A flexible high-performance visible photodetector is constructed using PAni-AuNP composite with low loading of AuNP, and optoelectronic properties of the device are evaluated. The present study demonstrates that a plasmonic hybrid nanocomposite prepared by a single-step novel plasma-based dry process could solve the low lifetime and performance-related issues of organic optoelectronic devices.

  6. Preparation of α-Fe2O3 Nanofiber via Electrospinning Process

    Institute of Scientific and Technical Information of China (English)

    SHAO Chang-lu; YANG Xing-hua; GUAN Hong-yu; YU Na; LIU Yi-chun

    2004-01-01

    A thin PVA/FeCl3 composite fiber was prepared by using sol-gel processing and electrospinning tech niques. A nanofiber of α-Fe2O3 with the diameter of 50-150 nm was obtained via high temperature calcina tion of the PVA/FeCl3 composite fiber. The material was characterized by infra-red(IR) spectroscopy, X-ray diffraction(XRD), and scanning electron microscopy(SEM). The results show that the fiber after the calci nation at 700 ℃ was a pure α-Fe2O3 nanofiber.

  7. Biocompatible Nb2O5 thin films prepared by means of the sol-gel process.

    Science.gov (United States)

    Velten, D; Eisenbarth, E; Schanne, N; Breme, J

    2004-04-01

    Thin biocompatible oxide films with an optimised composition and structure on the surface of titanium and its alloys can improve the implant integration. The preparation of these thin oxide layers with the intended improvement of the surface properties can be realised by means of the sol-gel process. Nb2O5 is a promising coating material for this application because of its extremely high corrosion resistance and thermodynamic stability. In this study, thin Nb2O5 layers ( TiO2 sol-gel coated cp-titanium concerning the spreading of cells, collagen I synthesis and wettability.

  8. Furnace bottom rise mechanism in preparation of Al-Si alloys by electrothermal process

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The experiments of preparation of Al-Si alloys by electrothermal process were carried out respectively in 20 kW, 100 kW and 1 800 kW DC arc furnaces. The mechanism of furnace bottom rise was studied.It was found that the bottom rise can be divided into three types, including the low bottom temperature, abnormal reducing reaction and carbide deposition. The furnace bottom rise is related to the carbon ratio of the briquet, the heating speed of the briquet and the parameters and operation of furnace.

  9. Macroporous Titania Monolith Prepared via Sol-gel Process with Polymer Foam as the Template

    Institute of Scientific and Technical Information of China (English)

    REN, Jian; DU, Zhong-Jie; ZHANG, Chen; LI, Hang-Quan

    2006-01-01

    Macroporous titania monoliths were prepared via sol-gel method using polymer foam as templates. The polymer foam polymerized via concentrated emulsion polymerization was immerged in a solution of titanium(Ⅳ) isopropoxide in 2-propanol, which underwent a sol-gel process. The organic components were subsequently removed by calcination. The effects of various parameters, including the nature of the monomer, the volume fraction of dispersed phase of the concentrated emulsion, and concentration of the sol-gel solution were investigated. The SEM micrographs of the macroporous titania monoliths thus obtained showed that the porous structure of the final material was effectively controllable.

  10. Preparation of selective surfaces of black cobalt by the sol-gel process

    Energy Technology Data Exchange (ETDEWEB)

    Barrera, E.C.; Viveros, T.G.; Morales, U. [Universidad Nacional Autonoma de Mexico, Iztapalapa (Mexico)

    1996-09-01

    Black cobalt, Co{sub 3}O{sub 4}, thin solid coatings on stainless steel and glass substrates have been prepared by the dip coating technique via the sol-gel route using a CoCl{sub 2} precursor. The coatings produced on substrates exhibit a blue to black colours as a function of the film thickness. Sols have been made from a cobalt acetate precursor 0.1 M, and for such conditions, the dip coating process gives 0.08-0.25 {mu}m thick uniform films per dipping, depending on the viscocity of the sol. (Author)

  11. A New Approach for Preparing Effective Inhibition Film on Copper Based on Self-assembled Process

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A new method for preparing effective inhibition film on copper has been developed. Phenylthiourea (PT) was first absorbed to copper surface to form a monolayer. 1-Dodecanethiol (DT) was then assembled on the surface for modification. Finally, AC voltage was loaded on copper covered the mixed film to improve it further. After these processes, an effective inhibition film was gained because of its high charge transfer resistance and low corrosion current density shown in electrochemical impedance spectra and polarization. The inhibition efficiency was more than 97%.

  12. PREPARATION AND SECOND-ORDER OPTICAL NONLINEARITY OF NOVEL PHENOXYSILICON NETWORKS BY SOL-GEL PROCESS

    Institute of Scientific and Technical Information of China (English)

    Xiao Huang; Jian Wang; Ling-zhi Zhang; Zhi-gang Cai; Zhao-xi Lianga

    2001-01-01

    Four phenoxysilicon networks for nonlinear optical (NLO) applications were designed and prepared by an extended sol-gel process without additional H20 and catalyst. All poled polymer network films possess high second-order nonlinear optical coefficients (d33) of 10-?~10-8 esu. The investigation of NLO temporal stability at room temperature and elevated temperature (120°C) indicated that these films exhibit high d33 stability because the orientation of the chromophores are locked in the phenoxysilicon organic/inorganic networks.

  13. Preparation of Ca Doped Lanthanum Chromite by Sol-Gel Process

    Institute of Scientific and Technical Information of China (English)

    Zang Bangqiang; Ao Qing; Li Dehui; Sun Liangcheng; Liu Ruwei

    2004-01-01

    Super fine particles of calcium-doped lanthanum chromites were prepared by the sol-gel process in which the chelating agent was citric acid and the dispersant agent was ethylene glycol. The phase of fine particles was analyzed by XRD and the size and shape of the particles were investigated by TEM. The result shows that the nano-particles of La1-xCaxCrO3 can be obtained by the way of Ca2+ complex singly with citric acid and being calcined at 700 ℃.

  14. Ultraviolet Spectrum of Nanometer Zinc Oxide Prepared by Sol-Gel Process

    Institute of Scientific and Technical Information of China (English)

    Xiaoping Liang; Xiaohui Wang; Shaobo Xin; Yajin Liu

    2006-01-01

    Zinc oxide nanometer powders were prepared by the sol-gel process. The sol and the powders characteristic of absorbing ultraviolet light is detected by the ultraviolet spectrometer. The results indicate the concentration of zinc acetate dihydrate in isopropyl alcohol solution and the final pH value of the aqueous sol have effect on the UV absorption of the sol.The nanometer zinc oxide has strong absorption at 200 nm~360 nm, and over 90% ultraviolet in the range of 200 nm~360 nm wavelength are absorbed. The characteristic of absorbing ultraviolet light of zinc oxide increases as the particle size of zinc oxide decreases.

  15. The Impact of the Delivery of Prepared Power Point Presentations on the Learning Process

    Directory of Open Access Journals (Sweden)

    Auksė Marmienė

    2011-04-01

    Full Text Available This article describes the process of the preparation and delivery of Power Point presentations and how it can be used by teachers as a resource for classroom teaching. The advantages of this classroom activity covering some of the problems and providing a few suggestions for dealing with those difficulties are also outlined. The major objective of the present paper is to investigate the students ability to choose the material and the content of Power Point presentations on professional topics via the Internet as well as the ability to prepare and deliver the presentation in front of the audience. The factors which determine the choice of the presentation subject are also analysed in this paper. After the delivery students were requested to self- and peer-assess the difficulties they faced in preparation and performance of the presentations by writing the reports. Learners’ attitudes to the choice of the topic of Power Point presentations were surveyed by administering a self-assessment questionnaire.

  16. Evaluation of an intravenous preparation information system for improving the reconstitution and dilution process.

    Science.gov (United States)

    Jo, Yun Hee; Shin, Wan Gyoon; Lee, Ju-Yeun; Yang, Bo Ram; Yu, Yun Mi; Jung, Sun Hoi; Kim, Hyang Sook

    2016-10-01

    There are very few studies reporting the impact of providing intravenous (IV) preparation information on quality use of antimicrobials, particularly regarding their reconstitution and dilution. Therefore, to improve these processes in IV antimicrobial administration, an IV preparation information system (IPIS) was implemented in a hospital. We aimed to evaluate the effect of improving reconstitution and dilution by implementing an IPIS in the electronic medical record (EMR) system. Prescriptions and activity records of nurses for injectable antimicrobials that required reconstitution and dilution for IV preparation from January 2008 to December 2013 were retrieved from EMR, and assessed based on packaging label information for reconstituting and diluting solutions. We defined proper reconstitution and dilution as occurring when the reconstitution and dilution solutions prescribed were consistent with the nurses' acting records. The types of intervention in the IPIS were as follows: a pop-up alert for proper reconstitution and passive guidance for proper dilution. We calculated the monthly proper reconstitution rate (PRR) and proper dilution rate (PDR) and evaluated the changes in these rates and trends using interrupted time series analyses. Prior to the initiation of the reconstitution alert and dilution information, the PRR and PDR were 12.7 and 46.1%, respectively. The reconstitution alert of the IPIS rapidly increased the PRR by 41% (pinformation on dilution solutions was ineffective. Furthermore, solutions to ensure the continuous effectiveness of alert systems are warranted and should be actively sought. Copyright © 2016. Published by Elsevier Ireland Ltd.

  17. Preparation and Support of Patients through the Transplant Process: Understanding the Recipients' Perspectives

    Directory of Open Access Journals (Sweden)

    Oliver Mauthner

    2012-01-01

    Full Text Available Preparation for heart transplant commonly includes booklets, instructional videos, personalized teaching sessions, and mentorship. This paper explores heart transplant recipients’ thoughts on their preparation and support through the transplant process. Twenty-five interviews were audio-/videotaped capturing voice and body language and transcribed verbatim. Coding addressed language, bodily gesture, volume, and tone in keeping with our visual methodology. Recipients reported that only someone who had a transplant truly understands the experience. As participants face illness and life-altering experiences, maintaining a positive attitude and hope is essential to coping well. Healthcare professionals provide ongoing care and reassurance about recipients’ medical status. Mentors, family members, and close friends play vital roles in supporting recipients. Participants reported that only heart transplant recipients understood the experience, the hope, and ultimately the suffering associated with living with another persons’ heart. Attention needs to be focused not solely on the use of teaching modalities, but also on the development of innovative support networks. This will promote patient and caregiver engagement in self-management. Enhancing clinicians’ knowledge of the existential aspects of transplantation will provide them with a nuanced understanding of the patients’ experience, which will ultimately enhance their ability to better prepare and support patients and their caregivers.

  18. Process for the preparation of composite crystalline aluminium silicates and their use as catalyst (carrier)

    Energy Technology Data Exchange (ETDEWEB)

    Van Erp, W.A.; Huizinga, T.; Seelen-Kruijssen, J.

    1989-01-31

    A process is presented for the preparation of a composite crystalline aluminum silicate by maintaining an aqueous alkaline starting mixture comprising one or more silicon compounds, one or more aluminium compounds, one or more compounds of metals from Group Ia of the Periodic Table and organic nitrogen compounds at an elevated temperature, until composite crystalline aluminium silicate has formed. Subsequently, crystalline silicate is separated from the mother liquor, wherein the various compounds are present in the starting mixture in defined molar ratios. These silicates can be used as catalyst or catalyst carrier in dewaxing hydrocarbon oils, to which process this invention further relates. To be used in such a process, the alkali metal content of the composite silicates must be reduced to less than 0.1 wt%. If desired, the performance of the silicates can be improved by using them simultaneously as carrier for one or more catalytically active metals from Groups VIb, VIIb and VIII8 of the Periodic Table or compounds thereof. The hydrocarbon oils which are to be dewaxed are preferably selected from the group consisting of lubricating oils and transformer oils (in order to reduce their pour point), and kerosenes and gas oils (in order to reduce their freezing point). Additionally, this invention relates to hydrocarbon oils which have been dewaxed according to the process of the invention. Furthermore, the invention relates to molecular sieves which comprise a composite crystalline aluminum silicate prepared as hereinbefore described, and to the application of such molecular sieves in a process for separating hydrocarbons. 5 tabs.

  19. Preparation and characterization of Tripterygium wilfordii multi-glycoside nanoparticle using supercritical anti-solvent process.

    Science.gov (United States)

    Chen, Fengli; Li, Tong; Li, Shuangyang; Hou, Kexin; Liu, Zaizhi; Li, Lili; Cui, Guoqiang; Zu, Yuangang; Yang, Lei

    2014-02-17

    The aim of this study was to prepare nanosized Tripterygium wilfordii multi-glycoside (GTW) powders by the supercritical antisolvent precipitation process (SAS), and to evaluate the anti-inflammatory effects. Ethanol was used as solvent and carbon dioxide was used as an antisolvent. The effects of process parameters such as precipitation pressure (15-35 MPa), precipitation temperature (45-65 °C), drug solution flow rates (3-7 mL/min) and drug concentrations (10-30 mg/mL) were investigated. The nanospheres obtained with mean diameters ranged from 77.5 to 131.8 nm. The processed and unprocessed GTW were characterized by scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy and thermal gravimetric analysis. The present study was designed to investigate the beneficial effect of the GTW nanoparticles on adjuvant-induced arthritis in albino rats. The processed and unprocessed GTW were tested against Freund's complete adjuvant-induced arthritis in rats. Blood samples were collected for the estimation of interleukins (IL-1α, IL-1β) and tumor necrosis factor-α (TNF-α). It was concluded that physicochemical properties and anti-inflammatory activity of GTW nanoparticles could be improved by physical modification, such as particle size reduction using supercritical antisolvent (SAS) process. Further, SAS process was a powerful methodology for improving the physicochemical properties and anti-inflammatory activity of GTW.

  20. Preparation and Characterization of Tripterygium wilfordii Multi-Glycoside Nanoparticle Using Supercritical Anti-Solvent Process

    Directory of Open Access Journals (Sweden)

    Fengli Chen

    2014-02-01

    Full Text Available The aim of this study was to prepare nanosized Tripterygium wilfordii multi-glycoside (GTW powders by the supercritical antisolvent precipitation process (SAS, and to evaluate the anti-inflammatory effects. Ethanol was used as solvent and carbon dioxide was used as an antisolvent. The effects of process parameters such as precipitation pressure (15–35 MPa, precipitation temperature (45–65 °C, drug solution flow rates (3–7 mL/min and drug concentrations (10–30 mg/mL were investigated. The nanospheres obtained with mean diameters ranged from 77.5 to 131.8 nm. The processed and unprocessed GTW were characterized by scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy and thermal gravimetric analysis. The present study was designed to investigate the beneficial effect of the GTW nanoparticles on adjuvant-induced arthritis in albino rats. The processed and unprocessed GTW were tested against Freund’s complete adjuvant-induced arthritis in rats. Blood samples were collected for the estimation of interleukins (IL-1α, IL-1β and tumor necrosis factor-α (TNF-α. It was concluded that physicochemical properties and anti-inflammatory activity of GTW nanoparticles could be improved by physical modification, such as particle size reduction using supercritical antisolvent (SAS process. Further, SAS process was a powerful methodology for improving the physicochemical properties and anti-inflammatory activity of GTW.

  1. A one bath chemo-enzymatic process for preparation of absorbent cotton

    Directory of Open Access Journals (Sweden)

    A.S.M. Raja

    2016-09-01

    Full Text Available Cotton is the raw material for preparation of absorbent cotton. Raw cotton has to be subjected to scouring and bleaching processes for making it absorbent by removing the naturally present wax, protein and minerals in the fibre. The scouring is done at 115 °C using alkali followed by bleaching at boiling condition using alkaline hydrogen peroxide solution. The effluent coming out of such processes contains high COD and BOD values. Due to the stringent environmental regulation and great awareness among the public about environment, worldwide attempts have been made to develop green and sustainable chemical processing of materials. Based on the above, in the present study efforts have been made to develop an eco-friendly one bath preparatory process for the production of absorbent cotton using chemo-enzymatic formulation. The result indicated that absorbent cotton produced using the developed process fulfilled the required performance properties as per pharmacopoeia in comparable with the conventional process made one.

  2. Preparation of poly (L-lactic acid) microspheres by droplet-freezing process

    Energy Technology Data Exchange (ETDEWEB)

    Mao Yi [School of Materials Science and Engineering, Southeast University, Nanjing 211189 (China); Jiangsu Key Laboratory of Advanced Metallic Materials, Nanjing 211189 (China); Dong Yinsheng, E-mail: dongys@seu.edu.cn [School of Materials Science and Engineering, Southeast University, Nanjing 211189 (China); Jiangsu Key Laboratory of Advanced Metallic Materials, Nanjing 211189 (China); Lin Pinghua [School of Materials Science and Engineering, Southeast University, Nanjing 211189 (China); Huazhong University of Science and Technology, Wuhan 430074 (China); Chu Chenglin; Sheng Xiaobo; Guo Chao [School of Materials Science and Engineering, Southeast University, Nanjing 211189 (China); Jiangsu Key Laboratory of Advanced Metallic Materials, Nanjing 211189 (China)

    2011-01-01

    A recently developed process of microsphere preparation, named droplet-freezing process is introduced in this paper. The PLLA microspheres were fabricated by the droplet-freezing process, the diameter and porosity of the microspheres were measured, and the micro-morphologies of the microspheres were characterized by scanning electron microscopy (SEM). The formation process of microspheres was achieved by two steps: first, after droplets dropped off the delivery tube, they became approximately spherical in the air under the effect of the surface tension; second, droplets dropped into liquid condensate and maintained the spherical shape, and were frozen during the free settling process. Experimental results indicated that the microspheres fabricated by the droplet-freezing process have uniform diameters and the diameter can be controlled properly, along with the increase of the PLLA concentration, the size of microspheres increases, but the porosity of the microspheres decreases. The microspheres with high porosity can be obtained with a low concentration of the PLLA solution. SEM analysis revealed that the surfaces and interiors of the microsphere contain plentiful and interconnected micro pores. The microspheres are hopeful to be applied in bone tissue engineering.

  3. Preparation and mechanical properties of silicon oxycarbide fibers from electrospinning/sol-gel process

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaofei [School of Materials Sciences and Engineering, Tianjin University, 300072 Tianjin (China); Gong, Cairong, E-mail: gcr@tju.edu.cn [School of Materials Sciences and Engineering, Tianjin University, 300072 Tianjin (China); Fan, Guoliang [School of Materials Sciences and Engineering, Tianjin University, 300072 Tianjin (China)

    2011-12-15

    Graphical abstract: Ceramic fibers, silicon oxycarbide (SiOC) fibers were demonstrated and showed higher mechanical properties from electrospinning/sol-gel process at 1000 Degree-Sign C. Highlights: Black-Right-Pointing-Pointer SiOC fibers with low cost are promising to substitute the non-oxide fibers. Black-Right-Pointing-Pointer Successful preparation of SiOC fibers by electrospinning/sol-gel process. Black-Right-Pointing-Pointer Confirmation of the designed product using material characterization methods. Black-Right-Pointing-Pointer The SiOC fibers prepared at 1000 Degree-Sign C possess higher strength (967 MPa). -- Abstract: Silicon oxycarbide (SiOC) fibers were produced through the electrospinning of the solution containing vinyltrimethoxysilane and tetraethoxysilane in the course of sol-gel reaction with pyrolysis to ceramic. The effect of the amount of spinning agent Polyvinylpyrrolidone (PVP) on the dope spinnability was investigated. At a mass ratio of PVP/alkoxides = 0.05, the spinning sol exhibited an optimal spinnable time of 50 min and generated a large quantity of fibers. Electrospun fibers were characterized by Fourier transform infrared spectroscopy (FTIR), thermo gravimetric analysis-differential scanning calorimetry (TGA-DSC), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The SEM results revealed that the SiOC fibers had a smooth surface and dense cross-section, free of residue pores and cracks. The XPS results gave high content of SiC (13.99%) in SiOC fibers. The SiOC fibers prepared at 1000 Degree-Sign C had a high tensile strength of 967 MPa and Young's modulus of 58 GPa.

  4. Fieldcrest Cannon, Inc. Advanced Technical Preparation. Statistical Process Control (SPC). PRE-SPC 11: SPC & Graphs. Instructor Book.

    Science.gov (United States)

    Averitt, Sallie D.

    This instructor guide, which was developed for use in a manufacturing firm's advanced technical preparation program, contains the materials required to present a learning module that is designed to prepare trainees for the program's statistical process control module by improving their basic math skills in working with line graphs and teaching…

  5. Alcohol sensing of tin oxide thin film prepared by sol–gel process

    Indian Academy of Sciences (India)

    Sunita Mishra; C Ghanshyam; Nathai Ram; Satinder Singh; R P Bajpai; R K Bedi

    2002-06-01

    The present paper describes the alcohol sensing characteristics of spin coated SnO2 thin film deposited by using sol–gel process. The sensitivity of the film was measured at different temperatures and different concentrations of alcohol at ppm level. Alcohol detection result shows peak sensitivity at 623 K. The variation of sensitivity and ethanol concentration has shown a linear relationship up to 1150 ppm and after that it saturates. The response time measurement of the sensor was also observed and it was found that the response time is 30 sec. The results obtained favour the sol–gel process as a low cost method for the preparation of thin films with a high sensing characteristic.

  6. Multi-physical field coupling simulation of TCVI process for preparing carbon/carbon composites

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    To prepare Carbon/Carbon (C/C) composites with advanced performance, the thermal gradient chemical vapor infiltration (TCVI) process has been optimized by simulation. A 2D axisymmetric unstable model was built, which included convection, conduction, diffusion, densification reactions in the pores and the evolution of the porous medium. The multi-physical field coupling model was solved by finite element method (FEM) and iterative calculation. The time evolution of the fluid, temperature and preform density field were obtained by the calculation. It is indicated that convection strongly affects the temperature field. For the preform of carbon/carbon composites infiltrated for 100 h by TCVI, the radial average densities from simulation agrees well with those from experiment. The model is validated to be reliable and the simulation has capability of forecasting the process.

  7. Multi-physical field coupling simulation of TCVI process for preparing carbon/carbon composites

    Institute of Scientific and Technical Information of China (English)

    JIAO YanQiong; LI HeJun; LI KeZhi

    2009-01-01

    To prepare Carbon/Carbon (C/C) composites with advanced performance, the thermal gradient chemi-cal vapor infiltration (TCVI) process has been optimized by simulation.A 2D axisymmetric unstable model was built, which included convection, conduction, diffusion, densification reactions in the pores and the evolution of the porous medium.The multi-physical field coupling model was solved by finite element method (FEM) and iterative calculation.The time evolution of the fluid, temperature and pre-form density field were obtained by the calculation.It is indicated that convection strongly affects the temperature field.For the preform of carbon/carbon composites infiltrated for 100 h by TCVI, the radial average densities from simulation agrees well with those from experiment.The model is validated to be reliable and the simulation has capability of forecasting the process.

  8. Preparation of ferromagnetic binary alloy fine fibers byorganic gel-thermal reduction process

    Institute of Scientific and Technical Information of China (English)

    SHEN Xiang-qian; CAO Kai; ZHOU Jian-xin

    2006-01-01

    Ferromagnetic metal fibers with a high aspect ratio (length/diameter) are attractive for use as high performance electromagnetic interference shielding materials. Ferromagnetic binary alloy fine fibers of iron-nickel, iron-cobalt and cobalt-nickel were prepared by the organic gel-thermal reduction process from the raw materials of critic acid and metal salts. These alloy fibers synthesized were featured with a diameter of about 1 μm and a length as long as 1 m. The structure, thermal decomposition process and morphologies of the gel precursors and fibers derived from thermal reduction of the gel precursors were characterized by FTIR, XRD, TG/DSC and SEM. The gel spinnability largely depends on the molecular structure of metal- carboxylates formed during the gel formation. The gel consisting of linear-type structural molecules shows good spinnability.

  9. Preparation of ferromagnetic metal fine fibers by organic gel-thermal reduction process

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The organic gel-thermal reduction process was used for the preparation of ferromagnetic metal Ni, Co and Fe fine fibers from the raw materials of citric acid, lactic acid and metal salts. The structure, thermal decomposition process and morphologies of the gel precursors and fibers derived from thermal reduction of these gel precursors were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, thermo-gravimetric/differential scanning calorimetry and scanning electron microscopy. The results show that spinnability of gel largely depends on molecular structure of metal-carboxylate complex that is a linear-type structure formed in the gel. As a result, the gels exhibit a good spinnability. Metal Ni, Co and Fe fine fibers are featured with diameters of around 1 urn and a high aspect ratio up to 1×106.

  10. The earth as a living planet: Human-type diseases in the earthquake preparation process

    CERN Document Server

    Contoyiannis, Y F; Eftaxias, K

    2013-01-01

    The new field of complex systems supports the view that a number of systems arising from disciplines as diverse as physics, biology, engineering, and economics may have certain quantitative features that are intriguingly similar. The earth is a living planet where many complex systems run perfectly without stopping at all. The earthquake generation is a fundamental sign that the earth is a living planet. Recently, analyses have shown that human-brain-type disease appears during the earthquake generation process. Herein, we show that human-heart-type disease appears during the earthquake preparation of the earthquake process. The investigation is mainly attempted by means of critical phenomena, which have been proposed as the likely paradigm to explain the origins of both heart electric fluctuations and fracture induced electromagnetic fluctuations. We show that a time window of the damage evolution within the heterogeneous Earth's crust and the healthy heart's electrical action present the characteristic feat...

  11. Preparation of DyFe2 and TbFe2 by Reduction-Diffusion Process

    Institute of Scientific and Technical Information of China (English)

    Guangsi GUO; Guangtai WANG; Zhitong SUI

    2004-01-01

    The pure intermetallic compounds (Tb1-xDyx)Fe2 are super-magnetostriction materials, which were produced from DyFe2and TbFe2 in this paper. The thermodynamic possibility and kinetic feasible conditions for DyFe2 and TbFe2 preparation by reduction-diffusion in Ca-Dy2O3-Fe and Ca-Tb4O7-Fe systems were analyzed and the products of DyFe2 and TbFe2 were confirmed by XRD. The contracting core model was applied to describe the reduction-diffusion process in which the diffusion is a rate-controlled step. The apparent activation energies of DyFe2 and TbFe2 processes are 45 and 39 k J/mol respectively.

  12. Photochromic organic-inorganic composite materials prepared by sol-gel processing: properties and potentials

    Science.gov (United States)

    Hou, Lisong; Mennig, Martin; Schmidt, Helmut K.

    1994-09-01

    The sol-gel method which features a low-temperature wet-chemical process opens vast possibilities to incorporating organic dyes into solid matrices for various optical applications. In this paper we present our experimental results on the sol-gel derived photochromic organic- inorganic composite (Ormocer) materials following an introductory description of the sol-gel process and a brief review on the state of the art of the photochromic solids prepared using this method. Our photochromic spirooxazine-Ormocer gels and coatings possess better photochromic response and color-change speed than the corresponding photochromic polymer coatings and similar photochemical stability to the latter. Further developments are proposed as to tackle the temperature dependence problem and further tap the potentialities of the photochromic dye-Ormocer material for practical applications.

  13. Microstructure Control of Nanoporous Silica Thin Film Prepared by Sol-gel Process

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Nanoporous silica films were prepared by sol-gel process with base, acid and base/acid two-step catalysis.Transmission electron microscope (TEM) and particle size analyzer were used to characterize the microstructure and the particle size distribution of the sols. Scanning electron microscopy (SEM), atomic force microscopy (AFM) and spectroscopic ellipsometer were used to characterize the surface microstructure and the optical properties of the silica films. Stability of the sols during long-term storage was investigated. Moreover,the dispersion relation of the optical constants of the silica films, and the control of the microstructure and properties of the films by changing the catalysis conditions during sol-gel process were also discussed.

  14. Synthesis control and characterization of hydroxyapatite prepared by wet precipitation process

    Directory of Open Access Journals (Sweden)

    Maria Helena Santos

    2004-12-01

    Full Text Available Several techniques have been utilized for the preparation of hydroxyapatite (HA and other calcium phosphates for the development of biomaterials. It is vital to know the reaction kinetics to be able to control the material obtained by the aqueous solution route. In the present work, HA has been produced by different wet precipitation processes and different experimental conditions. Calcium hydroxide, calcium phosphate, ammonium phosphate and phosphoric acid were used as reagents. The precipitate was dried at 100 °C overnight and then some samples were treated at 900 °C for 2 h. The powder samples were characterized by scanning electron microscopy (SEM, X-ray fluorescence (XRF and X-ray diffraction (XRD analyses. SEM photomicrographs showed an aggregate powder, granular to dense and suggested typical columnar particles. Qualitative XRF showed that the main components of HA powders were calcium and phosphorus. Pure HA and other phases according to processing parameters were observed by XRD analysis.

  15. Preparation and Characterization of Nanosized LiCoO2 by Sol-Gel Process

    Institute of Scientific and Technical Information of China (English)

    ZHOU; YingKe

    2001-01-01

    In the intense search for high-energy density cathode materials for use in lithium-ion rechargeable battery technology, LiCoO2 has become the first, and one of the most promising, for commercial applications1. Sol-gel chemistry has recently evolved as a powerful approach for preparing inorganic materials such as glasses and ceramics2. The improved sol-gel process is based on the ability of certain weak acids to form polybasic acid chelates with various cations. These chelates can undergo polyesterification when heated in a polyhydroxyl alcohol to form a solid polymeric resin through which the cations are uniformly distributed. Thus the resin retains homogeneity on the atomic scale and may be calcined at low temperature to yield fine particulate oxides. Using this method, it is possible to obtain phase-pure ultrafine crystalline nanophases after firing the ploymeric precursors at some appointed temperature for several hours. In this work we reported that nanosized LiCoO2 were prepared by the improved sol-gel process.  ……

  16. Preparation and Characterization of Nanosized LiCoO2 by Sol-Gel Process

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ In the intense search for high-energy density cathode materials for use in lithium-ion rechargeable battery technology, LiCoO2 has become the first, and one of the most promising, for commercial applications1. Sol-gel chemistry has recently evolved as a powerful approach for preparing inorganic materials such as glasses and ceramics2. The improved sol-gel process is based on the ability of certain weak acids to form polybasic acid chelates with various cations. These chelates can undergo polyesterification when heated in a polyhydroxyl alcohol to form a solid polymeric resin through which the cations are uniformly distributed. Thus the resin retains homogeneity on the atomic scale and may be calcined at low temperature to yield fine particulate oxides. Using this method, it is possible to obtain phase-pure ultrafine crystalline nanophases after firing the ploymeric precursors at some appointed temperature for several hours. In this work we reported that nanosized LiCoO2 were prepared by the improved sol-gel process.

  17. Separating limits on preparation versus online processing in multitasking paradigms: Evidence for resource models.

    Science.gov (United States)

    Mittelstädt, Victor; Miller, Jeff

    2017-01-01

    We conducted 2 multitasking experiments to examine the finding that first-task reaction times (RTs) are slower in the psychological refractory period (PRP) paradigm than in the prioritized processing (PP) paradigm. To see whether this difference between the 2 paradigms could be explained entirely by differences in first-task preparation, which would be consistent with the standard response selection bottleneck (RSB) model for multitasking interference, we compared the size of this difference for trials in which a second-task stimulus actually occurred against the size of the difference for trials without any second-task stimulus. The slowing of first-task RTs in the PRP paradigm relative to the PP paradigm was larger when the second-task stimulus appeared than when it did not, indicating that the difference cannot be explained entirely by between-paradigm differences in first-task preparation. Instead, the results suggest that the slowing of first-task RTs in the PRP paradigm relative to the PP paradigm is partly because of differences between paradigms in the online reallocation of processing capacity to tasks. Thus, the present results provide new evidence supporting resource models over the RSB model. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  18. Preparation and photocatalytic kinetics of nano-ZnO powders by precipitation stripping process

    Institute of Scientific and Technical Information of China (English)

    Dongxiang ZHANG; Hang XU; Min XUE; Wenguo XU; V TARASOV

    2008-01-01

    Ultra-fine zinc oxalate powders were prepared through a precipitation stripping method with bis(2-ethyl-hexyl) phosphate (HDEHP) diluted by tetrachloride carbon as the extractant,and oxalic acid ethanol aqueous solution as the re-extractant and precipitator.Zinc oxide powders were obtained by decomposing zinc oxalate powders at 450℃.The prepared zinc oxide powders were characterized by transmission electron microscope (TEM),Scanning elec-tron microscope (SEM),Thermogravimetric analysis (TG),X-ray diffraction (XRD) and Fourier transmission infrared (FT-IR) spectrum.The photocatalytic performance of methylene blue by zinc oxide was studied based on the Langmuir model and Photo-Layer model.The results show that some zinc oxide powders were micro-multipore mate-rials with hexagonal crystal.The particle size was around 32 nm.The photocatalytic process was the control step in the chemical reaction.The photo catalytic process followed pseudo-first order kinetics and ,OH concentration inside the photo-layer in different reaction condition were calcu-lated according to the Photo-Layer model.

  19. Polyethylene glycol-hirudin conjugates, process for preparing them and their use for the treatment of thromboses

    NARCIS (Netherlands)

    Bischoff, Rainer; Transgene, S.A.

    1994-01-01

    The present invention relates to a process for preparing a polyethylene glycol (or derivatives)-hirudin conjugate. It also relates to the polyethylene glycol (or derivatives)-hirudin conjugate obtained and its use as medicinal product for the..

  20. [Research process of the preparation of electrostatic spinning of poly-glycerol sebacate and the application in tissue engineering].

    Science.gov (United States)

    Zhang, Xiaoming; Li, Wenho

    2015-10-01

    Poly-glycerol sebacate (PGS) is a novel biodegradable elastomer, it has been widely applied in the biomedical fields of heart, blood vessel and cartilage owing to its excellent biological performance, mechanical property and degradability. Electrostatic spinning is a preparation method of tissue engineering scaffolds with the characteristics of convenience, processing controllability and cost efficiency. In this paper, the author reviewed the research process of electrostatic spinning preparation and the application in the field of tissue engineering.

  1. System Engineering on the Use for Ares I,V - the Simpler, the Better

    Science.gov (United States)

    Kelly, William; Greene, William D.; Greasley, Paul; Ackerman, Peter C.

    2008-01-01

    The Ares I and Ares V Vehicles will utilize the J-2X rocket engine developed for NASA by the Pratt & Whitney Rocketdyne Company. The J-2X is an improved higher power version of the original J-2 engine used during the Apollo program. With higher power and updated requirements for safety and performance, the J-2X becomes a new engine using state-of-the-art design methodology, materials and manufacturing processes. The implementation of Systems Engineering (SE) principles enables the rapid J-2X development program to remain aligned with the ARES I and V vehicle programs, Meeting the aggressive development schedule is a challenge. Coordinating the best expertise thai NASA and PWR have to offer requires effectively utilizing resources at multiple sites. This presents formidable communication challenges. SE allows honest and open discussions of issues and problems. This simple idea is often overlooked in large and complex SE programs. Regular and effective meetings linking SE objectives to component designs are used to voice differences of opinions with customer and contractor in attendance so that the best mutual decisions can be made on the shortest possible schedule. Regular technical interchange meetings on secure program wide computer networks and CM processes are effective,in the "Controlled Change" process that exemplifies good SE. Good communication is a key effective SE implementation. The System of Systems approach is the vision of the Orion program which facilitates the establishment of dynamic SE processes at all levels including the engine. SE enables requirements evolution by facilitating organizational and process agility. Flow down and distribution of requirements is controlled by Allocation Reports which breakdown numerical design objectives (weight, reliability, etc.) into quanta goals for each component area. Linked databases of design and verification requirements helps eliminate redundancy and potential mistakes inherent m separated systems. Another

  2. An Intensified Vibratory Milling Process for Enhancing the Breakage Kinetics during the Preparation of Drug Nanosuspensions.

    Science.gov (United States)

    Li, Meng; Zhang, Lu; Davé, Rajesh N; Bilgili, Ecevit

    2016-04-01

    As a drug-sparing approach in early development, vibratory milling has been used for the preparation of nanosuspensions of poorly water-soluble drugs. The aim of this study was to intensify this process through a systematic increase in vibration intensity and bead loading with the optimal bead size for faster production. Griseofulvin, a poorly water-soluble drug, was wet-milled using yttrium-stabilized zirconia beads with sizes ranging from 50 to 1500 μm at low power density (0.87 W/g). Then, this process was intensified with the optimal bead size by sequentially increasing vibration intensity and bead loading. Additional experiments with several bead sizes were performed at high power density (16 W/g), and the results were compared to those from wet stirred media milling. Laser diffraction, scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, and dissolution tests were used for characterization. Results for the low power density indicated 800 μm as the optimal bead size which led to a median size of 545 nm with more than 10% of the drug particles greater than 1.8 μm albeit the fastest breakage. An increase in either vibration intensity or bead loading resulted in faster breakage. The most intensified process led to 90% of the particles being smaller than 300 nm. At the high power intensity, 400 μm beads were optimal, which enhanced griseofulvin dissolution significantly and signified the importance of bead size in view of the power density. Only the optimally intensified vibratory milling led to a comparable nanosuspension to that prepared by the stirred media milling.

  3. Sustained release of risperidone from biodegradable microspheres prepared by in-situ suspension-evaporation process.

    Science.gov (United States)

    An, Taekun; Choi, Juhyuen; Kim, Aram; Lee, Jin Ho; Nam, Yoonjin; Park, Junsung; Sun, Bo kyung; Suh, Hearan; Kim, Cherng-ju; Hwang, Sung-Joo

    2016-04-30

    Risperidone-loaded poly (D,L-lactide-co-glycolide) (PLGA) microspheres were prepared with a suspension-evaporation process with an aqueous suspension containing an in situ-formed aluminum hydroxide inorganic gel (SEP-AL process) and evaluated for encapsulation efficiency, particle size, surface morphology, glass transition temperature, in vitro drug release profile, and in vivo behavior. The SEP-AL microspheres were compared with conventional oil-in-water (O/W) emulsion solvent evaporation method using polyvinylalcohol (PVA) as an emulsifier (CP-PVA process). The microspheres were spherical in shape. DSC measurements showed that risperidone crystallinity was greatly reduced due to the homogeneous distribution of risperidone in PLGA microspheres. In vitro drug release profile from the microspheres showed a sigmoidal pattern of negligible initial burst up to 24h and minimal release (time-lag) for 7 days. After the lag phase, slow release took a place up to 25 days and then rapid release occurred sharply for 1 week. In vivo rat pharmacokinetic profile from the microspheres showed very low blood concentration level at the initial phase (up to 24h) followed by the latent phase up to 21 days. At the 3rd week, main phase started and the blood concentration of the drug increased up to the 5th week, and then gradually decreased. The risperidone-loaded PLGA microspheres produced by SEP-AL process showed excellent controlled release characteristics for the effective treatment of schizophrenia patients.

  4. Effects of Shot Peening Process on Thermal Cycling Lifetime of TBCs Prepared by EB-PVD

    Institute of Scientific and Technical Information of China (English)

    ZHOU Zhao-hui; GONG Sheng-kai; LI He-fei; XU Hui-bin; ZHANG Chun-gang; WANG Lu

    2007-01-01

    Conventional two-layered thermal barrier coatings (TBCs) are prepared by electron beam physical vapor deposition (EB-PVD)with ZrO2-8 wt% Y2O3 (8YSZ) as top coat and CoCrAlY as bond coat on disk-shaped Ni based super-alloy. In this paper, three kinds of shot peening process with different lengths of operating time were adopted for bond coating. As a result, changes took place in its surface roughness and the surface micro-hardness. A thermal cycling test at 1 273 K×55 min and another at room temperature for 5 min were performed to study the effects of shot peening process on the thermal cycling lifetime of TBCs. It is found that a moderate shot peening process will be able to prolong the life time. The oxidation dynamic of the as-processed TBCs basically accords with the parabolic rule, and the oxidation test also attests to the spallation between YSZ and thermal growth oxide (TGO) responsible mainly for the failure of TBCs.

  5. From cognitive motor preparation to visual processing: The benefits of childhood fitness to brain health.

    Science.gov (United States)

    Berchicci, M; Pontifex, M B; Drollette, E S; Pesce, C; Hillman, C H; Di Russo, F

    2015-07-09

    The association between a fit body and a fit brain in children has led to a rise of behavioral and neuroscientific research. Yet, the relation of cardiorespiratory fitness on premotor neurocognitive preparation with early visual processing has received little attention. Here, 41 healthy, lower and higher fit preadolescent children were administered a modified version of the Eriksen flanker task while electroencephalography (EEG) and behavioral measures were recorded. Event-related potentials (ERPs) locked to the stimulus onset with an earlier than usual baseline (-900/-800 ms) allowed investigation of both the usual post-stimulus (i.e., the P1, N1 and P2) as well as the pre-stimulus ERP components, such as the Bereitschaftspotential (BP) and the prefrontal negativity (pN component). At the behavioral level, aerobic fitness was associated response accuracy, with higher fit children being more accurate than lower fit children. Fitness-related differences selectively emerged at prefrontal brain regions during response preparation, with larger pN amplitude for higher than lower fit children, and at early perceptual stages after stimulus onset, with larger P1 and N1 amplitudes in higher relative to lower fit children. Collectively, the results suggest that the benefits of being aerobically fit appear at the stage of cognitive preparation prior to stimulus presentation and the behavioral response during the performance of a task that challenges cognitive control. Further, it is likely that enhanced activity in prefrontal brain areas may improve cognitive control of visuo-motor tasks, allowing for stronger proactive inhibition and larger early allocation of selective attention resources on relevant external stimuli. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

  6. Multi criteria decision making to select the suitable method for the preparation of nanoparticles using an analytical hierarchy process.

    Science.gov (United States)

    Velmurugan, R; Selvamuthukumar, S; Manavalan, R

    2011-11-01

    Selecting the right method for the preparation of nanoparticles is a crucial decision. A wrong decision can result in the product having to be formulated and developed again. One tool that can be useful in determining the most appropriate method is the Analytical Hierarchy Process (AHP). AHP has been employed in almost all areas related to decision-making problems. In this paper, the results of a case study illustrate that the AHP concept can assist designers in the effective evaluation of various methods available for the preparation of nanoparticles. This paper presents the methodology of selecting the most suitable method for preparing nanoparticles using the analytical hierarchy process.

  7. Preparation, Processing, and Characterization of Oriented Polycrystalline Zeolite and Aluminophosphate Membranes

    Science.gov (United States)

    Stoeger, Jared Andrew

    Since the advent of zeolite membranes, speculation on their industrial applicability has been closely monitored, although widespread commercialization has been hampered by limitations in fabrication and post-synthesis processing. Economical, energy-efficient technology breakthroughs require an evaluation of a range of material candidates which show robustness and reliability. Straightforward manufacturing techniques should be devised to generate thousands of square meters of membrane area; however, this demands control of structural characteristics on the scale of nanometers. As described in this dissertation, the path forward will be forged by exploiting the intrinsic crystalline properties of zeolites or aluminophosphates for the next advancement in membrane technology. A facile method is described for the preparation of silicalite-1 (MFI zeolite type) membranes using the secondary growth technique on symmetric porous stainless steel tubes. Activation through rapid thermal processing (RTP), a lamp-based heat-treatment process used as a critical fabrication step in silicon integrated circuit manufacturing, is proven to reduce the density of non-zeolitic transport pathways which are detrimental to high-resolution molecular sieving. RTP-treated membranes are shown to have enhanced performance in the binary separation of vapor-phase isomers (p-/o-xylene), gas-phase isomers (n-/i-butane), and alcohol/water when compared to membranes activated at a much slower heating rate but otherwise similarly-prepared. The performance is discussed in the context of the market potential for industrially-attractive separations: the recovery of p-xylene from an isomeric mixture or alcohol biofuels from aqueous post-fermentation streams. Hydrothermal growth techniques for the preparation and characterization of continuous aluminophosphate (AFI zeolite type) membranes with a preferential crystallographic alignment on porous alpha-Al2O3 disc supports are demonstrated. A mechanism is

  8. Spray-coating process in preparing PTFE-PPS composite super-hydrophobic coating

    Directory of Open Access Journals (Sweden)

    Rui Weng

    2014-03-01

    Full Text Available In order to improve the performance of a liquid-floated rotor micro-gyroscope, the resistance of the moving interface between the rotor and the floating liquid must be reduced. Hydrophobic treatment can reduce the frictional resistance between such interfaces, therefore we proposed a method to prepare a poly-tetrafluoroethylene (PTFE-poly-phenylene sulphide (PPS composite super-hydrophobic coating, based on a spraying process. This method can quickly prepare a continuous, uniform PTFE-PPS composite super-hydrophobic surface on a 2J85 material. This method can be divided into three steps, namely: pre-treatment; chemical etching; and spraying. The total time for this is around three hours. When the PTFE concentration is 4%, the average contact angle of the hydrophobic coating surface is 158°. If silicon dioxide nanoparticles are added, this can further improve the adhesion and mechanical strength of the super-hydrophobic composite coating. The maximum average contact angle can reach as high as 164° when the mass fraction of PTFE, PPS and silicon dioxide is 1:1:1.

  9. Microstructure of polyacrylonitrile-based activated carbon fibers prepared from solvent-free coagulation process

    Directory of Open Access Journals (Sweden)

    Norhaniza Yusof

    2016-02-01

    Full Text Available Polyacrylonitrile precursor fibers prepared using a solvent-free coagulation process were stabilized, carbonized, and physically activated by carbon dioxide into activated carbon fibers (ACFs. The activation temperature varied from 600 to 900 °C while the activation time was 1 h. Atomic force microscopy was used to observe the surface morphology, as well as the surface roughness of the ACFs. Higher pyrolysis temperature formed rougher surfaces, and increased the pore sizes. Meanwhile, Fourier transform infrared spectroscopy revealed more conversion of oxygen containing functional groups to carbonaceous materials as the activation temperature increased. Moreover, the microstructure properties were thoroughly characterized by the X-ray photoelectron spectroscopy (XPS and X-ray diffraction (XRD studies. XRD analysis showed that the activation of the ACFs shrank the ordered structure, reducing the D-spacing from 0.358 to 0.347 nm for the fibers prepared at activation temperatures of 600 to 900 °C. Meanwhile, XPS analysis concluded that that the oxygen containing functional groups were still retained even at high activation temperatures while the nitrogen containing functional groups were reduced during the high temperature activation in the CO2 atmosphere.

  10. Effect of sodium citrate on preparation of nano-sized cobalt particles by organic colloidal process

    Institute of Scientific and Technical Information of China (English)

    Huaping ZHU; Hao LI; Huiyu SONG; Shijun LIAO

    2009-01-01

    Nano-sized cobalt particles with the diameter of 2 nm were prepared via an organic colloidal process with sodium formate, ethylene glycol and sodium citrate as the reducing agent, the solvent and the complexing agent, respectively. The effects of sodium citrate on the yield, crystal structure, particle size and size distribution of the prepared nano-sized cobalt particles were then investigated. The results show that the average particle diameter decreases from 200 nm to 2 nm when the molar ratio of sodium citrate to cobalt chloride changes from 0 to 6. Furthermore, sodium citrate plays a crucial role in the controlling of size distribution of the nano-sized particles. The size distribution of the particle without sodium citrate addition is in range from tens of nanometers to 300 or 400 nm, while that with sodium citrate addition is limited in the range of (2±0.25) nm. Moreover, it is found that the addition of sodium citrate as a complex agent could decrease the yield of the nano-sized cobalt particle.

  11. Effect of process variables on the preparation of artificial bone cements

    Energy Technology Data Exchange (ETDEWEB)

    Santos Junior, J.G.F.; Melo, P.A.; Pinto, J.C., E-mail: pinto@peq.coppe.ufrj.br, E-mail: jjunior@peq.coppe.ufrj.br, E-mail: melo@peq.coppe.ufrj.br [Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE/UFRJ), RJ (Brazil). Programa de Engenharia Quimica; Pita, V.J.R.R., E-mail: vjpita@ima.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Instituto de Macromoleculas; Nele, M., E-mail: nele@eq.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Escola de Quimica

    2013-10-15

    The present work concerns the preparation of bone cements based on poly(methyl methacrylate) (PMMA), used mainly for prosthesis fixation and cavity filling for correction of human bone failures. A typical bone cement recipe contains methyl methacrylate, which polymerizes in situ during cement application. An inherent problem of this reaction is the large amount of heat released during the cement preparation, which may lead to irreparable damage of living tissues. Optimization of PMMA-based bone cement recipes is thus an important step towards safe and reliable clinical usage of these materials. Important process variables related to the reaction temperature profile and the mixing of the recipe constituents were studied in order to allow for the adequate production of bone cements. It is shown that the average molar mass and size of the PMMA particles used in the production of the bone cement, as well as incorporation of radiopaque contrast, co-monomers and fillers into the bone recipe play fundamental roles in the course of the polymerization reaction. Furthermore, the injection vessel geometry may interfere dramatically with the temperature profile and the time for its occurrence. Finally, it has been observed that the morphology of the PMMA particles strongly affects the mixing of the bone cement components. (author)

  12. Processing and Preparation of Advanced Stirling Convertors for Extended Operation at NASA Glenn Research Center

    Science.gov (United States)

    Oriti, Salvatore M.; Cornell, Peggy A.

    2008-01-01

    The U.S. Department of Energy (DOE), Lockheed Martin Space Company (LMSC), Sunpower Inc., and NASA Glenn Research Center (GRC) have been developing an Advanced Stirling Radioisotope Generator (ASRG) for use as a power system on space science missions. This generator will make use of the free-piston Stirling convertors to achieve higher conversion efficiency than currently available alternatives. NASA GRC is supporting the development of the ASRG by providing extended operation of several Sunpower Inc. Advanced Stirling Convertors (ASCs). In the past year and a half, eight ASCs have operated in continuous, unattended mode in both air and thermal vacuum environments. Hardware, software, and procedures were developed to prepare each convertor for extended operation with intended durations on the order of tens of thousands of hours. Steps taken to prepare a convertor for long-term operation included geometry measurements, thermocouple instrumentation, evaluation of working fluid purity, evacuation with bakeout, and high purity charge. Actions were also taken to ensure the reliability of support systems, such as data acquisition and automated shutdown checkouts. Once a convertor completed these steps, it underwent short-term testing to gather baseline performance data before initiating extended operation. These tests included insulation thermal loss characterization, low-temperature checkout, and full-temperature and power demonstration. This paper discusses the facilities developed to support continuous, unattended operation, and the processing results of the eight ASCs currently on test.

  13. Application of a Dual-Arm Robot in Complex Sample Preparation and Measurement Processes.

    Science.gov (United States)

    Fleischer, Heidi; Drews, Robert Ralf; Janson, Jessica; Chinna Patlolla, Bharath Reddy; Chu, Xianghua; Klos, Michael; Thurow, Kerstin

    2016-10-01

    Automation systems with applied robotics have already been established in industrial applications for many years. In the field of life sciences, a comparable high level of automation can be found in the areas of bioscreening and high-throughput screening. Strong deficits still exist in the development of flexible and universal fully automated systems in the field of analytical measurement. Reasons are the heterogeneous processes with complex structures, which include sample preparation and transport, analytical measurements using complex sensor systems, and suitable data analysis and evaluation. Furthermore, the use of nonstandard sample vessels with various shapes and volumes results in an increased complexity. The direct use of existing automation solutions from bioscreening applications is not possible. A flexible automation system for sample preparation, analysis, and data evaluation is presented in this article. It is applied for the determination of cholesterol in biliary endoprosthesis using gas chromatography-mass spectrometry (GC-MS). A dual-arm robot performs both transport and active manipulation tasks to ensure human-like operation. This general robotic concept also enables the use of manual laboratory devices and equipment and is thus suitable in areas with a high standardization grade.

  14. Preparation of Water-Repellent Glass by Sol-Gel Process Using Perfluoroalkylsilane and Tetraethoxysilane.

    Science.gov (United States)

    Jeong, Hye-Jeong; Kim, Dong-Kwon; Lee, Soo-Bok; Kwon, Soo-Han; Kadono, Kohei

    2001-03-01

    Coating films on glass substrate were prepared by sol-gel process using alkoxide solutions containing perfluoroalkylsilane (PFAS) and tetraethoxysilane (TEOS). The physical properties of the coating films were characterized by SEM, FT-IR, and XRD. And their surface properties were investigated by measuring contact angles and atomic compositions. Transparent coating films with smooth surface and uniform thickness could be obtained. The contact angles of the coating films for water and methylene iodide are extremely high, at 118 degrees and 97 degrees, respectively, and their surface free energies are about 9.7 dyn/cm. It was found that the water-repellent glass prepared is very hydrophobic and exhibits excellent water-repellency. Hydrophobic perfluoroalkyl groups are preferentially enriched to the outermost layer at the coating film-air interface, and two layers probably exist in the coating film. The upper layer oriented toward the air is composed of mainly perfluoroalkyl groups originating from PFAS, and the lower layer is composed of mainly -OSiO- groups originating from TEOS. The heat treatment after drying step cannot influence the surface enrichment of the perfluoroalkyl group. The hydrolysis reaction should be more completely done before the dip coating step to obtain lower surface free energy. The burning temperature should be less than 300 degrees C because the perfluoroalkyl group begins to decompose from this temperature. Copyright 2001 Academic Press.

  15. Influence of microwave irradiation on the preparation of novolacs for the shell process

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    In this paper, the characteristics of the preparation of novolacs for the shell process under microwave irradiation are investigated. Both polymerization and dehydration of the resins under microwave irradiation are compared with those under conventional heating and further analysis is made. The results show that compared with those under conventional heating, the polymerization and dehydration time under microwave irradiation are shortened by 85.2% and 80.7% respectively; On the other hand, the polymerization and dehydration under microwave irradiation lead to a remarkable increase in flow distance of the resins. Furthermore, the polymerization under microwave irradiation leads to reduced cure time, while the dehydration under microwave irradiation causes a slight increase in cure time.

  16. Structure of nanocomposites of Al–Fe alloys prepared by mechanical alloying and rapid solidification processing

    Indian Academy of Sciences (India)

    S S Nayak; B S Murty; S K Pabi

    2008-06-01

    Structures of Al-based nanocomposites of Al–Fe alloys prepared by mechanical alloying (MA) and subsequent annealing are compared with those obtained by rapid solidification processing (RSP). MA produced only supersaturated solid solution of Fe in Al up to 10 at.% Fe, while for higher Fe content up to 20 at.% the nonequilibrium intermetallic Al5Fe2 appeared. Subsequent annealing at 673 K resulted in more Al5Fe2 formation with very little coarsening. The equilibrium intermetallics, Al3Fe (Al13Fe4), was not observed even at this temperature. In contrast, ribbons of similar composition produced by RSP formed fine cellular or dendritic structure with nanosized dispersoids of possibly a nano-quasicrystalline phase and amorphous phase along with -Al depending on the Fe content in the alloys. This difference in the product structure can be attributed to the difference in alloying mechanisms in MA and RSP.

  17. Copper/bamboo fabric composite prepared via a silver catalytic electroless deposition process for electromagnetic shielding

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Qian; Lu, Yinxiang [Fudan Univ., Shanghai (China). Dept. of Materials Science

    2013-09-15

    Copper/bamboo fabric composite prepared via a silver catalytic electroless plating process is reported. The microstructure of the composite was analyzed by means of scanning electron microscopy, which illustrated that the copper coating was composed of spherical particles and clusters. The composition and chemical state of the metal layer were measured using X-ray diffraction and energy-dispersive X-ray analysis spectra; copper and a small amount of nickel were detected. Mechanical properties were measured based on a standard (ISO 13934-1:1999) for the fabrics with and without copper coating. The breaking force for the composite was improved by about 16.8% compared to uncoated bamboo fabric. The electromagnetic interference shielding effectiveness of the composite was more than 40 dB at frequencies ranging from 0.2 to 1000MHz. The copper coating on bamboo fabric passed the Scotch {sup registered} -tape test. (orig.)

  18. Preparation and Characterization of M-Type Barium Ferrite Fibers via Aqueous Sol-Gel Process

    Institute of Scientific and Technical Information of China (English)

    GONG Cairong; FAN Guoliang; SONG Chonglin; L(U) Gang

    2007-01-01

    BaFe12O19 fibers was prepared via an aqueous sol-gel process using Fe(OH)( HCOO)2 synthesized in laboratory and Ba(CH3COO)2 as the original materials and citrate as the chelate. The rheological behaviour of spinnable sol was characterized on rheometer, and the development of gel fibers to barium ferrite fibers was studied by IR, TG and XRD. Morphology observation of the fibers was given on SEM, and the diameter of the obtained fibers was between 5 and 10 μm corresponding to different additives. The additives affected the surface tension of the precursor sol which had close relation to the microstructure of fibers. Sucrose and hydroxyethylic cellulose could improve the surface tension while diethanolamine and hexadecylamine reduce that of the precursor sol. And using diethanolamine or hexadecylamine as an additive, well-structured BaFe12O19 fibers could be obtained.

  19. Preparation of a Cation Exchanger from Cork Waste: Thermodynamic Study of the Ion Exchange Processes

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    An ion exchanger was prepared by sulfonation of cork-waste chars. The exchange properties of the resultant materialwere characterized using Na+, Ca2+ or Fe3+ aqueous solutions, The content of metal ions in the solutions weredetermined by atomic absorption spectrometry. On the basis of the results obtained, the chemical equilibrium andits thermodynamic aspects related to the ion exchange process were studied. It was found that equilibrium constantK varies by the order: Na+<Ca2+<Fe3+, its value increasing with increasing temperature, and that △H°>0 and△S°>0, with -△G° following the sequence: Ca2+>Na+>Fe3+,

  20. Comprehensive Utilization of Filter Residue from the Preparation Process of Zeolite-Based Catalysts

    Directory of Open Access Journals (Sweden)

    Shu-Qin Zheng

    2016-05-01

    Full Text Available A novel utilization method of filter residue from the preparation process of zeolite-based catalysts was investigated. Y zeolite and a fluid catalytic cracking (FCC catalyst were synthesized from filter residue. Compared to the Y zeolite synthesized by the conventional method, the Y zeolite synthesized from filter residue exhibited better thermal stability. The catalyst possessed wide-pore distribution. In addition, the pore volume, specific surface area, attrition resistance were superior to those of the reference catalyst. The yields of gasoline and light oil increased by 1.93 and 1.48 %, respectively. At the same time, the coke yield decreased by 0.41 %. The catalyst exhibited better gasoline and coke selectivity. The quality of the cracked gasoline had been improved.

  1. Amphoteric Starch in Simultaneous Process Preparation with Box-Behnken Design for Optimal Conditions

    Directory of Open Access Journals (Sweden)

    Sopa Cansee

    2008-01-01

    Full Text Available Cassava starch was chemically modified to produce an amphoteric starch. The amphoteric starch was prepared in a simultaneous process which was evaluated in relation to four factors: temperature (45-55 °C, 3-chloro-2-hydroxypropyltrimethylammonium chloride (CHPTAC, 4-12% and sodium tripolyphosphate (STP, 2-8% concentrations, and reaction time (2-6 h. The extent of amphoteric starch produced was determined by the degree of substitution (DS of the nitrogen content and percentage of phosphorus content. In addition, a quantitative response of yield and whiteness as well as pasting characteristics were tested. Response surface analysis showed that the DS (0.01-0.05 increased with increasing temperature, CHPTAC and reaction time. The phosphorus content (0.09-0.34% followed a parabolic shape with all of the factors. Consequently, the response surface methodology appears to be a powerful technique to determine the optimal conditions for the production of amphoteric starches.

  2. The Earth as a living planet: human-type diseases in the earthquake preparation process

    Science.gov (United States)

    Contoyiannis, Y. F.; Potirakis, S. M.; Eftaxias, K.

    2013-01-01

    The new field of complex systems supports the view that a number of systems arising from disciplines as diverse as physics, biology, engineering, and economics may have certain quantitative features that are intriguingly similar. The Earth is a living planet where many complex systems run perfectly without stopping at all. The earthquake generation is a fundamental sign that the Earth is a living planet. Recently, analyses have shown that human-brain-type disease appears during the earthquake generation process. Herein, we show that human-heart-type disease appears during the earthquake preparation of the earthquake process. The investigation is mainly attempted by means of critical phenomena, which have been proposed as the likely paradigm to explain the origins of both heart electric fluctuations and fracture-induced electromagnetic fluctuations. We show that a time window of the damage evolution within the heterogeneous Earth's crust and the healthy heart's electrical action present the characteristic features of the critical point of a thermal second-order phase transition. A dramatic breakdown of critical characteristics appears in the tail of the fracture process of heterogeneous system and the injured heart's electrical action. Analyses by means of Hurst exponent and wavelet decomposition further support the hypothesis that a dynamical analogy exists between the geological and biological systems under study.

  3. The effect of mastication on human motor preparation processing: a study with CNV and MRCP.

    Science.gov (United States)

    Sakamoto, Kiwako; Nakata, Hiroki; Honda, Yukiko; Kakigi, Ryusuke

    2009-07-01

    To clarify the effect of mastication on motor preparation processing using electroencephalography (EEG), we investigated the effect of mastication on contingent negative variation (CNV) and reaction time (RT) in Experiment 1, and movement-related cortical potentials (MRCPs) in Experiment 2. The twelve subjects performed four CNV or MRCP sessions, and in the Mastication condition chewed a gum base during the resting period between sessions, Pre (before chewing) and Post 1, 2, and 3 (after chewing). In the Control condition, the subjects performed the same sessions without chewing gum during the intervals between sessions on another day. In Experiment 1, the mean amplitudes of the early- and late-CNV were significantly larger in Mastication than Control at Post 2 and Post 3. RT also differed significantly between Mastication and Control at Post 3. By contrast, in Experiment 2, there were no significant differences between Mastication and Control for the mean amplitudes of MRCPs including Bereitschaftspotential (BP) and negative slope (NS') in any session. These results suggest that mastication influences cognitive processing reflected by CNV with stimulus-triggered movement, rather than motor-related processing reflected by MRCPs relating to self-initiated movement, and provide evidence concerning the mechanisms for the effect of mastication on the human brain.

  4. New process for preparing complex-shaped dielectric film similar to Mylar. [Polyethylene terephthalate

    Energy Technology Data Exchange (ETDEWEB)

    Lagasse, R.R.; Kraynik, A.M.

    1982-02-01

    A new thermoforming/heat-treatment process yields complex-shaped dielectric film having electrical and shrinkage properties similar to those of flat Mylar film. This similarity should extend to other physical properties because the new process is directly analogous to the process used to prepare Mylar. Commercially available poly(ethylene terephthalate) film is formed into a cavity at approx. 110/sup 0/C and then heat treated at approx. 180/sup 0/C. A laboratory-scale forming apparatus has produced cylindrically shaped films having depth/diameter ratio approx. 1, a tapered wall-section, and variation in wall thickness of < 3X. Evaluation of other forming methods suggests that the production rate and thickness uniformity can be improved with existing technology. Thermal shrinkage at 150/sup 0/C, 1 kHz dielectric constant from -55 to +70/sup 0/C, leakage current at 1 kV, and breakdown voltage have been measured for both the complex-shaped film and Mylar. These comparative measurements indicate that the complex-shaped film could replace the flat Mylar dielectric currently used in energy-storage capacitors. A complex-shaped energy-storage capacitor could enhance safety in certain nuclear weapon applications by allowing strong-link devices in a firing set to be enclosed by a weak link.

  5. Microwave processing for sample preparation to evaluate mitochondrial ultrastructural damage in hemorrhagic shock.

    Science.gov (United States)

    Josephsen, Gary D; Josephsen, Kelly A; Beilman, Greg J; Taylor, Jodie H; Muiler, Kristine E

    2005-12-01

    This is a report of the adaptation of microwave processing in the preparation of liver biopsies for transmission electron microscopy (TEM) to examine ultrastructural damage of mitochondria in the setting of metabolic stress. Hemorrhagic shock was induced in pigs via 35% total blood volume bleed and a 90-min period of shock followed by resuscitation. Hepatic biopsies were collected before shock and after resuscitation. Following collection, biopsies were processed for TEM by a rapid method involving microwave irradiation (Giberson, 2001). Samples pre- and postshock of each of two animals were viewed and scored using the mitochondrial ultrastructure scoring system (Crouser et al., 2002), a system used to quantify the severity of ultrastructural damage during shock. Results showed evidence of increased ultrastructural damage in the postshock samples, which scored 4.00 and 3.42, versus their preshock controls, which scored 1.18 and 1.27. The results of this analysis were similar to those obtained in another model of shock (Crouser et al., 2002). However, the amount of time used to process the samples was significantly shortened with methods involving microwave irradiation.

  6. A CHEMICAL PROCESS FOR PREPARING CELLULOSIC FIBERS HIERARCHICALLY FROM KENAF BAST FIBERS

    Directory of Open Access Journals (Sweden)

    Jinshu Shi

    2011-02-01

    Full Text Available The objective of this research was to evaluate an all-chemical process to prepare nano-scale to macro-scale cellulosic fibers from kenaf bast fibers, for polymer composite reinforcement. The procedure used in this all-chemical process included alkaline retting to obtain single cellulosic retted fiber, bleaching treatment to obtain delignified bleached fiber, and acidic hydrolysis to obtain both pure-cellulose microfiber and cellulose nanowhisker (CNW. At each step of this chemical process, the resultant fibers were characterized for crystallinity using X-ray diffraction (XRD, for functional groups using the Fourier Transform Infrared spectroscopy (FTIR, and for surface morphology using both the scanning electron microscopy (SEM and transmission electron microscopy (TEM. The chemical components of the different scale fibers were analyzed. Based on the raw kenaf bast fibers, the yields of retted fibers and bleached fibers were 44.6% and 41.4%. The yield of the pure cellulose microfibers was 26.3%. The yield of CNWs was 10.4%, where about 22.6% α-cellulose had been converted into CNWs. The fiber crystallinity increased as the scale of the fiber decreased, from 49.9% (retted single fibers to 83.9% (CNWs. The CNWs had fiber lengths of 100 nm to 1400 nm, diameters of 7 to 84 nm, and aspect ratios of 10 to 50. The incorporation of 9% (wt% CNWs in polyvinyl alcohol (PVA composites increased the tensile strength by 46%.

  7. The Earth as a living planet: human-type diseases in the earthquake preparation process

    Directory of Open Access Journals (Sweden)

    Y. F. Contoyiannis

    2013-01-01

    Full Text Available The new field of complex systems supports the view that a number of systems arising from disciplines as diverse as physics, biology, engineering, and economics may have certain quantitative features that are intriguingly similar. The Earth is a living planet where many complex systems run perfectly without stopping at all. The earthquake generation is a fundamental sign that the Earth is a living planet. Recently, analyses have shown that human-brain-type disease appears during the earthquake generation process. Herein, we show that human-heart-type disease appears during the earthquake preparation of the earthquake process. The investigation is mainly attempted by means of critical phenomena, which have been proposed as the likely paradigm to explain the origins of both heart electric fluctuations and fracture-induced electromagnetic fluctuations. We show that a time window of the damage evolution within the heterogeneous Earth's crust and the healthy heart's electrical action present the characteristic features of the critical point of a thermal second-order phase transition. A dramatic breakdown of critical characteristics appears in the tail of the fracture process of heterogeneous system and the injured heart's electrical action. Analyses by means of Hurst exponent and wavelet decomposition further support the hypothesis that a dynamical analogy exists between the geological and biological systems under study.

  8. THE STUDY OF PATTERNS OF PRE-EXTRUSION PREPARATION OIL CULTURES TO THE PRESSING PROCESS

    Directory of Open Access Journals (Sweden)

    L. N. Frolova

    2015-01-01

    Full Text Available One of the most promising oil crops in the Russian Federation is saffron. Camelina seeds contain from 26 to 46% oil, which is different from other oils rich in cruciferous gondoinic, linolenic and linoleic acids, and relatively low erucic acid, has a high content of the biologically active substances (sterols, carotenes and carotenoids, chlorophylls and tocopherols. The main task in the processing of oilseeds is the maximum extraction of oil with a high quality of the products obtained: unrefined oil, cake and meal. In conventional technology of oil, the raw material is subjected to repeated heating significantly. Proposed the following processing flow chart: camelina seeds were subjected to moisture-heat treatment beforehand in an extruder, and then hot-pressed to a screw press a single action, so that the oil content of the cake after pressing was 17-19%. When using an extrusion process is suppressed anti-nutritional properties contained in the seeds of camelina. Found that the oil obtained after the preliminary preparation of the extrusion as compared with the oil produced by traditional technology, comprises more tocopherols, phospholipids less chlorophyll, free fatty acids and peroxides. Thus, it has a longer shelf life, has good fluidity, easily refined.

  9. Preparation of wafer-level glass cavities by a low-cost chemical foaming process (CFP).

    Science.gov (United States)

    Shang, Jintang; Chen, Boyin; Lin, Wei; Wong, Ching-Ping; Zhang, Di; Xu, Chao; Liu, Junwen; Huang, Qing-An

    2011-04-21

    A novel foaming process-chemical foaming process (CFP)-using foaming agents to fabricate wafer-level micro glass cavities including channels and bubbles was investigated. The process consists of the following steps sequentially: (1) shallow cavities were fabricated by a wet etching on a silicon wafer; (2) powders of a proper foaming agent were placed in a silicon cavity, named 'mother cavity', on the etched silicon surface; (3) the silicon cavities were sealed with a glass wafer by anodic bonding; (4) the bonded wafers were heated to above the softening point of the glass, and baked for several minutes, when the gas released by the decomposition of the foaming agent in the 'mother cavity' went into the other sealed interconnected silicon cavities to foam the softened glass into cylindrical channels named 'daughter channels', or spherical bubbles named 'son bubbles'. Results showed that wafer-level micro glass cavities with smooth wall surfaces were achieved successfully without contamination by the CFP. A model for the CFP was proposed to predict the final shape of the glass cavity. Experimental results corresponded with model predictions. The CFP provides a low-cost avenue to preparation of micro glass cavities of high quality for applications such as micro-reactors, micro total analysis systems (μTAS), analytical and bio-analytical applications, and MEMS packaging.

  10. Hydrogenated Nanocrystalline Silicon Thin Films Prepared by Hot-Wire Method with Varied Process Pressure

    Directory of Open Access Journals (Sweden)

    V. S. Waman

    2011-01-01

    Full Text Available Hydrogenated nanocrystalline silicon films were prepared by hot-wire method at low substrate temperature (200∘C without hydrogen dilution of silane (SiH4. A variety of techniques, including Raman spectroscopy, low angle X-ray diffraction (XRD, Fourier transform infrared (FTIR spectroscopy, atomic force microscopy (AFM, and UV-visible (UV-Vis spectroscopy, were used to characterize these films for structural and optical properties. Films are grown at reasonably high deposition rates (>15 Å/s, which are very much appreciated for the fabrication of cost effective devices. Different crystalline fractions (from 2.5% to 63% and crystallite size (3.6–6.0 nm can be achieved by controlling the process pressure. It is observed that with increase in process pressure, the hydrogen bonding in the films shifts from Si–H to Si–H2 and (Si–H2n complexes. The band gaps of the films are found in the range 1.83–2.11 eV, whereas the hydrogen content remains <9 at.% over the entire range of process pressure studied. The ease of depositing films with tunable band gap is useful for fabrication of tandem solar cells. A correlation between structural and optical properties has been found and discussed in detail.

  11. Manganese ferrite prepared using reverse micelle process: Structural and magnetic properties characterization

    Energy Technology Data Exchange (ETDEWEB)

    Hashim, Mohd, E-mail: md.hashim09@gmail.com [Department of Physics, Aligarh Muslim University, Aligarh 202002 (India); Shirsath, Sagar E. [Spin Device Technology Centre, Department of Engineering, Shinshu University, Nagano 380-8553 (Japan); Meena, S.S. [Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Mane, M.L. [Department of Physics, S.G.R.G. Shinde Mahavidyalaya, Paranda 413502, MS (India); Kumar, Shalendra [School of Materials Science and Engineering, Changwon National University, Changwon, Gyeongnam 641-773 (Korea, Republic of); Bhatt, Pramod [Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Kumar, Ravi [Centre for Material Science Engineering, National Institute of Technology, Hamirpur, HP (India); Prasad, N.K.; Alla, S.K. [Deptartment of Metallurgical Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005 (India); Shah, Jyoti; Kotnala, R.K. [National Physical Laboratory (CSIR), Dr. K.S. Krishnan Road, New Delhi 110012 (India); Mohammed, K.A. [Department of Mathematics & Physics Sciences, College of Arts and Sciences, University of Nizwa, Nizwa (Oman); Şentürk, Erdoğan [Department of Physics, Sakarya University, Esentepe, 54187 Sakarya (Turkey); Alimuddin [Department of Physics, Aligarh Muslim University, Aligarh 202002 (India)

    2015-09-05

    Highlights: • Preparation of Mn{sup 3+} substituted MnFe{sub 2}O{sub 4} ferrite by Reverse microemulsion process. • Characterization by XRD, SEM, VSM, Mössbauer spectroscopy and dielectric measurements techniques. • Magnetic properties of MnFe{sub 2}O{sub 4} enhanced after Mn{sup 3+} substitution. • The dielectric constant and ac conductivity increased with Mn{sup 3+} substitution. - Abstract: Reverse microemulsion process was employed to prepare of nanocrystalline Mn{sup 3+} substituted MnFe{sub 2−x}Mn{sub x}O{sub 4} ferrites. The structural, magnetic and dielectric properties were studied for different concentrations of Mn{sup 3+}. The structural and microstructural properties were analyzed using X-ray diffraction technique (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy techniques. The phase identification of the materials was studied by Rietveld refined XRD patterns which reveals single phase with cubic symmetry for the samples. The lattice parameters were ranged in between 8.369 and 8.379 Å and do not show any significant change with the substitution of Mn{sup 3+}. The average particles size was found to be around 11 ± 3 nm. Magnetization results obtained from the vibrating sample magnetometer (VSM) confirm that the substitution of Mn{sup 3+} in MnFe{sub 2}O{sub 4} ferrite caused an increase in the saturation magnetization and coercivity. The dependence of Mössbauer parameters on Mn{sup 3+} substitution has been analyzed. Magnetic behavior of the samples were also studied at field cooled (FC) and zero field cooled (ZFC) mode. The dependence of Mössbauer parameters on Mn{sup 3+} substitution was also analyzed. All the magnetic characterization shows that Mn{sup 3+} substitution enhance the magnetic behavior of MnFe{sub 2}O{sub 4} ferrite nanoparticles.

  12. Preparation and Application of Chitosan Membranes to Filter Silver from X-ray Film Processing Wastes

    Science.gov (United States)

    Nyoman Rupiasih, N.; Rustam Purnomo, Rendra; Sumadiyasa, Made

    2016-04-01

    Chitosan is a natural polysaccharide biopolymer which has been widely used in different processes and applications. Chitosan based membranes have been used in reverse osmosis, gas separation, dialysis and pervaporation. The object of this research was investigating the possibility of chitosan membrane used as a filter for removing silver (Ag) from X-ray film processing wastes. Several of chitosan membranes such as M1, M2, M3 and M4 have been prepared for the purpose and filtration was done using dead-end filtration method. The filtration experiments were performed on a flat sheet membrane using pure water and X-ray film processing wastes as feeds. The analysis of silver concentration has been done by atomic absorption spectrometers (AAS). The results show that chitosan membrane M2 gave the highest filtration coefficient (Rcoeff ) i.e. 99.9%, with the pure water flux (PWF) and product flux (PF) are 2972.56 L/m2h and 1761.18 L/m2h respectively. The rejection coefficient of the membranes decreases with increasing the amount of chitosan, while the pure water flux and product flux are increased. The filtration coefficients show that the chitosan membranes are able to filter silver waste from X-ray film processing wastes with performance dependent on their characteristic such as pores size. This suggests that, chitosan membrane can be used as one method that is safe and friendly environment for recovering silver from X-ray film processing waste to improve the quality of treated to an acceptable quality level.

  13. 9 CFR 318.24 - Product prepared using advanced meat/bone separation machinery; process control.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Product prepared using advanced meat... MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION AND CERTIFICATION ENTRY INTO OFFICIAL ESTABLISHMENTS; REINSPECTION AND PREPARATION OF PRODUCTS General § 318.24 Product prepared using advanced meat...

  14. Effects of the preparation processes on structural, electronic, and optical properties of LaHoO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Siaï, Amira, E-mail: amira_siai@hotmail.fr [Laboratoire de Physico-Chimie des Matériaux Minéraux et leurs Applications, Centre National des Recherches en Sciences des Matériaux, B.P.73 Soliman 8027, Technopole Borj Cedria (Tunisia); Horchani-Naifer, Karima [Laboratoire de Physico-Chimie des Matériaux Minéraux et leurs Applications, Centre National des Recherches en Sciences des Matériaux, B.P.73 Soliman 8027, Technopole Borj Cedria (Tunisia); Haro-González, Patricia [Fluorescence Imaging Group, Department of physical material C-IV, Madrid Autonoma University, C/Francisco Tomas y Valiente 7, E-28049 Madrid (Spain); Férid, Mokhtar [Laboratoire de Physico-Chimie des Matériaux Minéraux et leurs Applications, Centre National des Recherches en Sciences des Matériaux, B.P.73 Soliman 8027, Technopole Borj Cedria (Tunisia)

    2016-04-15

    Highlights: • The preparation of LaHoO{sub 3} by combustion and hydrothermal techniques was performed. • The crystal structure and characterization of the synthesized oxides were carried out. • The lattice distortions have effects on Raman, luminescence and optical band gap. • Electronic properties and band structure have been carried out by DFT method. • Sample prepared by hydrothermal process gives higher emission intensities. - ABSTRACT: Lanthanum holmium oxide (LaHoO{sub 3}) was synthesized using combustion and hydrothermal processes in order to compare the effects of preparation method on structural, electronic, and optical properties. For this purpose, the as-prepared samples were characterized with infrared spectroscopy, Raman scattering, X-ray diffraction, and scanning electronic microscopy. The Rietveld refinements structure of as-prepared samples show that lattice distortions and volume expansion were obtained for LaHoO{sub 3} synthesized with hydrothermal method compared to combustion process. The luminescence properties were investigated upon 488 and 750 nm laser excitations. The emission curves show the presence of characteristic Ho{sup 3+} transitions with a higher emission intensity for a sample prepared by hydrothermal method than the one obtained by combustion process. The structures properties effects on the band structure and the density of states were realized via generalized gradient approximation functional with Hubbard correction. The lattice distortions were found to have effects on Raman, luminescence and optical band gap.

  15. Preparation and photocatalytic performance of ZrO{sub 2} nanotubes fabricated with anodization process

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Wei, E-mail: weijiang@scu.edu.cn; He, Jian; Zhong, Jiemin; Lu, Jiuyun; Yuan, Shaojun; Liang, Bin

    2014-07-01

    Anodization process is a facile method to prepare structured nano-material. In this research, anodization process of zirconium in (NH{sub 4}){sub 2}SO{sub 4}/NH{sub 4}F solution was studied systematically and the anodized zirconia was applied to degrade methyl orange (MO) solution under UV irradiation and compared with anodized titania nanotubes to determine the photoactivity of zirconia nanotubes. After anodization in aqueous electrolyte containing 1 M (NH{sub 4}){sub 2}SO{sub 4} and 0.25 wt% NH{sub 4}F for 120 min at 20 V, zirconia nanotubes (ZNT) with diameters of about 20 nm and lengths of about 600 nm were formed. The growth mechanism of ZNT was studied with SEM and TEM. The hypothesis of ZNT growth, in which electric etching process started at the pits and further to deepen in situ to form nanotubes, was confirmed by the SEM. The anodization process on the sanded rough Zr foil verified this assumption since the growth of ZNT occurred at the bottom of the ripples on Zr foil and gathered to form bundles at the peaks. The as-grown ZNT is a mixture of monoclinic and tetragonal ZrO{sub 2} crystals, which transforms into pure monoclinic structure after annealed at 300 °C. The unannealed ZNT has excellent photocatalytic performance with a MO photo-degradation rate of 94.45% after 4 h, even if contrasting to anodized titania. Reusing experiments confirmed that the decaying of photocatalytic performance of ZNT can be negligible in 6 times recycling.

  16. Fabrication and densification enhancement of SiC-particulate-reinforced copper matrix composites prepared via the sinter-forging process

    Institute of Scientific and Technical Information of China (English)

    Mohammadmehdi Shabani; Mohammad Hossein Paydar; Mohammad Mohsen Moshksar

    2014-01-01

    The fabrication of copper (Cu) and copper matrix silicon carbide (Cu/SiCp) particulate composites via the sinter-forging process was investigated. Sintering and sinter-forging processes were performed under an inert Ar atmosphere. The influence of sinter-forging time, tempera-ture, and compressive stress on the relative density and hardness of the prepared samples was systematically investigated and subsequently com-pared with that of the samples prepared by the conventional sintering process. The relative density and hardness of the composites were enhanced when they were prepared by the sinter-forging process. The relative density values of all Cu/SiCp composite samples were observed to decrease with the increase in SiC content.

  17. New polymorphs of 9-nitro-camptothecin prepared using a supercritical anti-solvent process.

    Science.gov (United States)

    Huang, Yinxia; Wang, Hongdi; Liu, Guijin; Jiang, Yanbin

    2015-12-30

    Recrystallization and micronization of 9-nitro-camptothecin (9-NC) has been investigated using the supercritical anti-solvent (SAS) technology in this study. Five operating factors, i.e., the type of organic solvent, the concentration of 9-NC in the solution, the flow rate of 9-NC solution, the precipitation pressure and the temperature, were optimized using a selected OA16 (4(5)) orthogonal array design and a series of characterizations were performed for all samples. The results showed that the processed 9-NC particles exhibited smaller particle size and narrower particle size distribution as compared with 9-NC raw material (Form I), and the optimum micronization conditions for preparing 9-NC with minimum particle size were determined by variance analysis, where the solvent plays the most important role in the formation and transformation of polymorphs. Three new polymorphic forms (Form II, III and IV) of 9-NC, which present different physicochemical properties, were generated after the SAS process. The predicted structures of the 9-NC crystals, which were consistent with the experiments, were performed from their experimental XRD data by the direct space approach using the Reflex module of Materials Studio. Meanwhile, the optimal sample (Form III) was proved to have higher cytotoxicity against the cancer cells, which suggested the therapeutic efficacy of 9-NC is polymorph-dependent.

  18. Preparation and characterization of Pd/C catalyst obtained in NH 3-mediated polyol process

    Science.gov (United States)

    Li, Huanqiao; Sun, Gongquan; Jiang, Qian; Zhu, Mingyuan; Sun, Shiguo; Xin, Qin

    Vulcan XC-72R carbon supported Pd nanoparticles was obtained in a NH 3-mediated polyol process without any protective agent and characterized by X-ray diffraction (XRD) and transmission electron microscope (TEM) techniques. The added NH 3 species is found to have a strong complex ability to Pd, which not only avoids the formation of Pd hydroxide precipitate resulted from Pd hydrolysis, but also restrains the further complete reduction of Pd. Temperature-programmed reduction equipped with a mass spectrometry (TPR-MS) is employed to study the reductive behavior of unreduced Pd complex in Pd/C catalyst and the results show that the post-treatment in a reductive atmosphere at higher temperature is needed to ensure the complete reduction of Pd. XRD patterns show the heat-treated Pd/C sample in a reductive atmosphere has a face centered cubic crystal structure and TEM image indicates that the dispersion of Pd nanoparticles on the carbon support is uniform and in a narrow particle size range. Thermodynamic data analysis is carried out to elucidate the possible reaction pathway for the preparation of Pd/C catalyst in this process. The obtained Pd/C catalyst shows high activity to formic acid oxidation and high selectivity to oxygen reduction reaction (ORR) with the presence of methanol.

  19. Process of preparing ethanol by continuous fermentation of polysaccharide-containing materials

    Energy Technology Data Exchange (ETDEWEB)

    Ehnstroem, L.K.J.

    1981-04-16

    The invention concerns a process of preparing ethanol by continuous fermentation of polysaccharide - containing raw materials. Fermentation, hereby, occurs in one or several fermentors while dividing one stream of the fermentation liquid into a yeast-concentrate stream and a yeast-free stream and, if neccessary, a sludge stream. The yeast-concentrate stream is re-fed into the fermentor and at least part of the yeast-free stream is directed into a simple evaporator corresponding to one or several distilling stages where it is separated partially in an ethanol-enriched initial vapour stream supplying a facility to produce the desired ethanol quality, and partially in a liquid initial bottom stream re-fed at least in part into the fermentor. The characteristic feature of this new process is that a raw-material stream is fed into a closed circuit containing the fermentor and the evaporator, and that, in the evaporator, the raw-material stream is hydrolysed to a fermentable state. This hydrolysis is carried out most favourably by enzymes - preferably a gluco-amylase - at a temperature ranging from 35/sup 0/C to 75/sup 0/C.

  20. Microstructure characterization of oxidation of aluminized coating prepared by a combined process

    Energy Technology Data Exchange (ETDEWEB)

    Liu, H.B. [College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, 29 Yudao Street, Nanjing 210016 (China); Tao, J. [College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, 29 Yudao Street, Nanjing 210016 (China)], E-mail: taojie@nuaa.edu.cn; Xu, J.; Chen, Z.F.; Sun, X.J.; Xu, Z. [College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, 29 Yudao Street, Nanjing 210016 (China)

    2008-08-31

    Alumina layer is a good candidate for the tritium penetration barrier that is important in the control of tritium losses due to permeation through structural materials used in high-temperature gas-cooled reactors and in fusion reactors. This paper describes the microstructure of the oxide film of the tritium penetration barrier formed on 316L stainless steel, which was prepared by a combined process, namely, aluminizing and oxidizing treatments using a double glow plasma technology. Microstructure and phase structure of the coatings investigated were examined by scanning electronic microscope (SEM), X-ray diffraction analysis (XRD) and transmission electron microscopy (TEM), respectively. The chemical composition and the chemical states of Al, O elements in the oxidation film were identified by X-ray photoelectron spectroscopy (XPS). After aluminization, the typical microstructure of the coating mainly consisted of an outer high aluminum-containing intermetallic compound layer (Fe{sub 2}Al{sub 5} and FeAl) and intermediate ferritic stainless steel ({alpha} Fe(Al))layer followed by the austenitic substrate. After the combined process, an oxide layer that consisted of Al{sub 2}O{sub 3} and spinel FeAl{sub 2}O{sub 4} had been successfully formed on the aluminizing coating surface, with an amorphous outmost surface and an underlying subsurface nanocrystalline structure.

  1. Synthesis and micowave characterization of conductive polyaniline prepared by continous polymerization process

    Science.gov (United States)

    Manaf, A.; Bimantoro, A.; Hafizah, M. AE; Andreas

    2017-07-01

    Results of synthesized polyaniline (PANi) prepared by a continuous polymerization process is reported. The purpose of this research is to obtain material absorber which maximum absorption. FTIR spectrum for synthesized PANi showed no double bond absorption peak at 3442 cm-1 which indicates the polymer chain was formed through repetition of single bonds. The results of the electrical conductivity measurement showed the value 17.5 μS/cm for synthesized PANI. The value increased dramatically to 3600, 1520 and 920 μS/cm after the addition of photonic acids of HClO4, H2SO4 and HCl respectively. Those values were obtained through sequences process. Results of particle size distribution confirmed that all synthesized PANi have nanoparticles. In addition, all synthesized PANi have shown electromagnetic wave absorbing properties in the frequency range 12-18 GHz. The best peak Reflection Loss (RL) values -10 dB (˜ 68 % absorption) and -25 dB (˜ 84 %) at 13 and 16.5 GHz respectively obtained on the PANi Emeraldine base (PANi-EB).

  2. Sol-gel Process in Preparation of Organic-inorganic Hybrid Materials

    Directory of Open Access Journals (Sweden)

    Macan, J

    2008-07-01

    Full Text Available Organic-inorganic hybrid materials are a sort of nanostructured material in which the organic and inorganic phases are mixed at molecular level. The inorganic phase in hybrid materials is formed by the sol-gel process, which consists of reactions of hydrolysis and condensation of metal (usually silicon alkoxides. Flexibility of sol-gel process enables creation of hybrid materials with varying organic and inorganic phases in different ratios, and consequently fine-tuning of their properties. In order to obtain true hybrid materials, contact between the phases should be at molecular level, so phase separation between thermodynamically incompatible organic and inorganic phases has to be prevented. Phase interaction can be improved by formation of hydrogen or covalent bonds between them during preparation of hybrid materials. Covalent bond can be introduced by organically modified silicon alkoxides containing a reactive organic group (substituent capable of reacting with the organic phase. In order to obtain hybrid materials with desired structures, a detailed knowledge of hydrolysis and condensation mechanism is necessary. The choice of catalyst, whether acid or base, has the most significant influence on the structure of the inorganic phase. Other important parameters are alkoxide concentration, water: alkoxide ratio, type of alkoxide groups, solvent used, temperature, purity of chemicals used, etc. Hydrolysis and condensation of organically modified silicon alkoxides are additionally influenced by nature and size of the organic supstituent.

  3. Determination of Ideal Broth Formulations Needed to Prepare Hydrous Cerium Oxide Microspheres via the Internal Gelation Process

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Jack Lee [ORNL; Chi, Anthony [ORNL

    2009-02-01

    A simple test tube methodology was used to determine optimum process parameters for preparing hydrous cerium oxide microspheres via the internal gelation process.1 Broth formulations of cerium ammonium nitrate [(NH4)2Ce(NO3)6], hexamethylenetetramine, and urea were found that can be used to prepare hydrous cerium oxide gel spheres in the temperature range of 60 to 90 C. A few gel-forming runs were made in which microspheres were prepared with some of these formulations to be able to equate the test-tube gelation times to actual gelation times. These preparations confirmed that the test-tube methodology is reliable for determining the ideal broth formulations.

  4. Preparation of polyaniline/sodium alanate hybrid using a spray-drying process

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, B. R., E-mail: bru-rms@yahoo.com.br, E-mail: fabiopassador@gmail.com, E-mail: pessan@ufscar.br; Passador, F. R., E-mail: bru-rms@yahoo.com.br, E-mail: fabiopassador@gmail.com, E-mail: pessan@ufscar.br; Pessan, L. A., E-mail: bru-rms@yahoo.com.br, E-mail: fabiopassador@gmail.com, E-mail: pessan@ufscar.br [Dep. de Engenharia de Materiais, Federal University of São Carlos (Brazil)

    2014-05-15

    Nowadays, hydrogen is highly interesting as an energy source, in particular in the automotive field. In fact, hydrogen is attractive as a fuel because it prevents air pollution and greenhouse emissions. One of the main problems with the utilization of hydrogen as a fuel is its on-board storage. The purpouse of this work was to develop a new hybrid material consisting of a polyaniline matrix with sodium alanate (NaAlH{sub 4}) using a spray-drying process. The polyaniline used for this experiment was synthesized by following a well-established method for the synthesis of the emeraldine base form of polyaniline using dodecylbenzenesulfonic acid as dopant. Micro particles of polyaniline/sodium alanate hybrids with 30 and 50 wt% of sodium alanate were prepared by using a spray-drying technique. Dilute solutions of polyaniline/sodium alanate were first prepared, 10g of the solid materials were mixed with 350 ml of toluene under stirring at room temperature for 24h and the solutions were dried using spray-dryer (Büchi, Switzerland) with 115°C of an inlet temperature. The hybrids were analyzed by differential scanning calorimetry, FT-IR and scanning electron microscopy (SEM). The addition of sodium alanate decreased the glass transition temperature of the hybrids when compared to neat polyaniline. FT-IR spectrum analysis was performed to identify the bonding environment of the synthesized material and was observed that simply physically mixture occurred between polyaniline and sodium alanate. The SEM images of the hybrids showed the formation of microspheres with sodium alanate dispersed in the polymer matrix.

  5. THERMAL, MECHANICAL, AND MOISTURE ABSORPTION PROPERTIES OF WOOD-TiO2 COMPOSITES PREPARED BY A SOL-GEL PROCESS

    OpenAIRE

    Xiaoqing Wang; Junliang Liu,; Yubo Chai

    2012-01-01

    Wood-TiO2 (titania) composites were prepared by a sol-gel process, in which wood was impregnated with the precursor solutions prepared from tetrabutyl titanate (TBT), followed by a curing step. The surface morphology and moisture absorption behavior of the wood composites, as well as their thermal and mechanical performances, were examined. Environmental scanning electron microscopy (ESEM) analysis revealed that TiO2 gels were deposited principally in the cell lumens and partly in the cell wa...

  6. Principle and Method of Preparation of Explosive Micro-particles Through the Supercritical Anti-solvent Process

    Institute of Scientific and Technical Information of China (English)

    JIN Liang-an; LIU Xue-wu; LI Zhi-yi; WANG Xiao-tong; YIN Xing-bo

    2005-01-01

    In explosive research area, one of important trends is to study on the preparation technology of explosive microparticles. A new principle and method based on supercritical anti-solvent (SAS) process is put forward and discussed for the preparation of explosive micro-particles. The satisfactory micro-particles of explosives can be obtained easily by its particular mechanism of creating micro-particles, and operating conditions at normal temperature. This method is good for further study and development.

  7. Mechanical properties of 9Cr–1W reduced activation ferritic martensitic steel weldment prepared by electron beam welding process

    Energy Technology Data Exchange (ETDEWEB)

    Das, C.R., E-mail: chitta@igcar.gov.in [Indira Gandhi Center for Atomic Research, Kalpakkam 603102 (India); Albert, S.K. [Indira Gandhi Center for Atomic Research, Kalpakkam 603102 (India); Sam, Shiju [Institute for Plasma Research, Gandhinagar (India); Mastanaiah, P. [Defense Research and Development Laboratory, Hyderabad (India); Chaitanya, G.M.S.K.; Bhaduri, A.K.; Jayakumar, T. [Indira Gandhi Center for Atomic Research, Kalpakkam 603102 (India); Murthy, C.V.S. [Defense Research and Development Laboratory, Hyderabad (India); Kumar, E. Rajendra [Institute for Plasma Research, Gandhinagar (India)

    2014-11-15

    Highlights: • Width of HAZ is smaller in the 9Cr–1W RAFM weldment prepared by EB process compared to that reported for TIG weldments in literature. • Weld joint is stronger than that of the base metal. • Toughness of weld metal prepared by EB welding process is comparable to that (in PWHT condition) prepared by TIG process. • DBTT of as-welded 9Cr–1W RAFM weldment prepared by EB process is comparable to that reported for TIG weld metal in PWHT condition. - Abstract: Microstructure and mechanical properties of the weldments prepared from 9Cr–1W reduced activation ferritic martensitic (RAFM) steel using electron beam welding (EBW) process were studied. Microstructure consists of tempered lath martensite where precipitates decorating the boundaries in post weld heat treated (PWHT) condition. Lath and precipitate sizes were found to be finer in the weld metal than in base metal. Accordingly, hardness of the weld metal was found to be higher than the base metal. Tensile strength of the cross weldment specimen was 684 MPa, which was comparable with the base metal tensile strength of 670 MPa. On the other hand, DBTT of 9Cr–1W weld metal in as-welded condition is similar to that reported for TIG weld metal in PWHT condition.

  8. Use of the GranuFlow Process in Coal Preparation Plants to Improve Energy Recovery and Reduce Coal Processing Wastes

    Energy Technology Data Exchange (ETDEWEB)

    Glenn A. Shirey; David J. Akers

    2005-12-31

    With the increasing use of screen-bowl centrifuges in today's fine coal cleaning circuits, a significant amount of low-ash, high-Btu coal can be lost during the dewatering step due to the difficulty in capturing coal of this size consist (< 100 mesh or 0.15mm). The GranuFlow{trademark} technology, developed and patented by an in-house research group at DOE-NETL, involves the addition of an emulsified mixture of high-molecular-weight hydrocarbons to a slurry of finesized coal before cleaning and/or mechanical dewatering. The binder selectively agglomerates the coal, but not the clays or other mineral matter. In practice, the binder is applied so as to contact the finest possible size fraction first (for example, froth flotation product) as agglomeration of this fraction produces the best result for a given concentration of binder. Increasing the size consist of the fine-sized coal stream reduces the loss of coal solids to the waste effluent streams from the screen bowl centrifuge circuit. In addition, the agglomerated coal dewaters better and is less dusty. The binder can also serve as a flotation conditioner and may provide freeze protection. The overall objective of the project is to generate all necessary information and data required to commercialize the GranuFlow{trademark} Technology. The technology was evaluated under full-scale operating conditions at three commercial coal preparation plants to determine operating performance and economics. The handling, storage, and combustion properties of the coal produced by this process were compared to untreated coal during a power plant combustion test.

  9. HTS current lead units prepared by the TFA-MOD processed YBCO coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Shiohara, K.; Sakai, S.; Ishii, Y. [Tokai University, 1117 Kita-Kaname, Hiratsuka, Kanagawa 259-1292 (Japan); Yamada, Y., E-mail: yyamaday@keyaki.cc.u-tokai.ac.j [Tokai University, 1117 Kita-Kaname, Hiratsuka, Kanagawa 259-1292 (Japan); Tachikawa, K. [Tokai University, 1117 Kita-Kaname, Hiratsuka, Kanagawa 259-1292 (Japan); Koizumi, T.; Aoki, Y.; Hasegawa, T. [SWCC Showa Cable System Co., LTD, 4-1-1 Minami-Hashimoto, Sagamihara, Kanagawa 229-1133 (Japan); Tamura, H.; Mito, T. [NIFS National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan)

    2010-11-01

    Two superconducting current lead units have been prepared using ten coated conductors of the Tri-Fluoro-Acetate - Metal Organic Deposition (TFA-MOD) processed Y{sub 1}Ba{sub 2}Cu{sub 3}O{sub 7-{delta}}(YBCO) coated conductors with critical current (I{sub c}) of about 170 A at 77 K in self-field. The coated conductors are 5 mm in width, 190 mm in length and about 120 {mu}m in overall thickness. The 1.5 {mu}m thick superconducting YBCO layer was synthesized through the TFA-MOD process on Hastelloy{sup TM} C-276 substrate tape with two buffer oxide layers of Gd{sub 2}Zr{sub 2}O{sub 7} and CeO{sub 2}. The five YBCO coated conductors are attached on a 1 mm thick Glass Fiber Reinforced Plastics (GFRP) board and soldered to Cu caps at the both ends. We prepared two 500 A-class current lead units. The DC transport current of 800 A was stably applied at 77 K without any voltage generation in all coated conductors. The voltage between both Cu caps linearly increased with increasing the applied current, and was about 350 {mu}V at 500 A in both current lead units. According to the estimated values of the heat leakage from 77 K to 4.2 K, the heat leakage for the current lead unit was 46.5 mW. We successfully attained reduction of the heat leakage because of improvement of the transport current performance (I{sub c}), a thinner Ag layer of YBCO coated conductor and usage of the GFRP board for reinforcement instead of a stainless steel board used in the previous study. The DC transport current of 1400 A was stably applied when the two current lead units were joined in parallel. The sum of the heat leakages from 77 K to 4.2 K for the combined the current lead units was 93 mW. In comparison with the conventional Cu current leads by gas-cooling, it could be noted that the heat leakage of the current lead is about one order of magnitude smaller than that of the Cu current lead.

  10. Simpler images, better results

    Science.gov (United States)

    Chance, Britton

    1999-03-01

    The very rapid development of optical technology has followed a pattern similar to that of nuclear magnetic resonance: first, spectroscopy and then imaging. The accomplishments in spectroscopy have been significant--among them, early detection of hematomas and quantitative oximetry (assuming that time and frequency domain instruments are used). Imaging has progressed somewhat later. The first images were obtained in Japan and USA a few years ago, particularly of parietal stimulation of the human brain. Since then, rapid applications to breast and limb, together with higher resolution of the brain now make NIR imaging of functional activation and tumor detection readily available, reliable and affordable devices. The lecture has to do with the applications of imaging to these three areas, particularly to prefrontal imaging of cognitive function, of breast tumor detection, and of localized muscle activation in exercise. The imaging resolution achievable in functional activation appears to be FWHM of 4 mm. The time required for an image is a few seconds or even much less. Breast image detection at 50 microsecond(s) ec/pixel results in images obtainable in a few seconds or shorter times (bandwidths of the kHz are available). Finally, imaging of the body organs is under study in this laboratory, particularly in the in utero fetus. It appears that the photon migration theory now leads to the development of a wide number of images for human subject tissue spectroscopy and imaging.

  11. Making Wireless Terminals Simpler

    DEFF Research Database (Denmark)

    Christensen, Søren Skovgaard; Popovski, Petar; De Carvalho, Elisabeth

    2005-01-01

    The exponential growth of user demands and the limitations of 3G systems have brought researchers and industry to propose solutions for the next generation. Among the requirements are higher bit rates and cheaper deployment. In this paper we focus on a terminal complexity problem related to chann...

  12. Individualization of training process as a leading construction of skiers’ training component in preparation for higher achievements

    Directory of Open Access Journals (Sweden)

    Vorfolomeeva L.A.

    2013-08-01

    Full Text Available The aim was to improve the process of preparation of skiers in preparation for higher achievements. It is spotted urgency of introduction of individualization in the training process, the principles and directions of realization. It is offered individualized relationship seen as consistent instructional techniques and forms of management training athletes. It is proved that increasing individualization rationality of functional reserves of athletes and prevent early retirement. Argues that the correction of the training process is the need for the development of genetic expression in the function of an athlete and popular sports specialization. It is noted that during the preparation of the highest achievements of a fundamentally important point is to ensure that the conditions under which the period of maximum susceptibility athlete to achieve the best results with the same period of the most intense and complex in the coordination for training loads.

  13. Preparation and Physicochemical Properties of 10-Hydroxycamptothecin (HCPT Nanoparticles by Supercritical Antisolvent (SAS Process

    Directory of Open Access Journals (Sweden)

    Baoyou Zhang

    2011-04-01

    Full Text Available The goal of the present work was to study the feasibility of 10-hydroxycamptothecin (HCPT nanoparticle preparation using supercritical antisolvent (SAS precipitation. The influences of various experimental factors on the mean particle size (MPS of HCPT nanoparticles were investigated. The optimum micronization conditions are determined as follows: HCPT solution concentration 0.5 mg/mL, the flow rate ratio of CO2 and HCPT solution 19.55, precipitation temperature 35 °C and precipitation pressure 20 MPa. Under the optimum conditions, HCPT nanoparticles with a MPS of 180 ± 20.3 nm were obtained. Moreover, the HCPT nanoparticles obtained were characterized by Scanning electron microscopy, Dynamic light scattering, Fourier-transform infrared spectroscopy, High performance liquid chromatography-mass spectrometry, X-ray diffraction and Differential scanning calorimetry analyses. The physicochemical characterization results showed that the SAS process had not induced degradation of HCPT. Finally, the dissolution rates of HCPT nanoparticles were investigated and the results proved that there is a significant increase in dissolution rate compared to unprocessed HCPT.

  14. Ergonomic intervention in aonla pricking operation during preserve preparation in food processing industries.

    Science.gov (United States)

    Rai, Arpana; Gandhi, Sudesh; Kumar, Nitin; Sharma, D K; Garg, M K

    2012-01-01

    Aonla is an important Indian fruit crop with great potential for processing into various quality products. Aonla preserve making is an important economic activity in our country. The pricking methods are age old, hence a hand operated aonla pricking machine was introduced in preserve making industries to speed up the pricking task. OWAS and RULA two of the most commonly used ergonomic assessment tools were evaluated for their efficacy in the assessment pricking along with Rating of perceived exertion scale. Analysis of working posture using RULA revealed that the pricking task with existing methods i.e. fork and hand tool requires immediate investigation and changes in working posture while with machine pricking investigations and changes are required soon. The results of OWAS indicated that the posture maintained while pricking with existing methods need to be changed in future planning while with machine was acceptable. The subjective assessment revealed that machine pricking was less exerting activity as compared to the existing methods. The preserve prepared from machine pricked fruit was most acceptable among consumers. Hence, in the form of machine ergonomic intervention was brought about in preservation industries which have proved beneficial for workers in terms of their safety and productivity.

  15. Effect of Orifice Diameter on Bubble Generation Process in Melt Gas Injection to Prepare Aluminum Foams

    Science.gov (United States)

    Yuan, Jianyu; Li, Yanxiang; Wang, Ningzhen; Cheng, Ying; Chen, Xiang

    2016-06-01

    The bubble generation process in conditioned A356 alloy melt through submerged spiry orifices with a wide diameter range (from 0.07 to 1.0 mm) is investigated in order to prepare aluminum foams with fine pores. The gas flow rate and chamber pressure relationship for each orifice is first determined when blowing gas in atmospheric environment. The effects of chamber pressure ( P c) and orifice diameter ( D o) on bubble size are then analyzed separately when blowing gas in melt. A three-dimensional fitting curve is obtained illustrating both the influences of orifice diameter and chamber pressure on bubble size based on the experimental data. It is found that the bubble size has a V-shaped relationship with orifice diameter and chamber pressure neighboring the optimized parameter ( D o = 0.25 mm, P c = 0.4 MPa). The bubble generation mechanism is proposed based on the Rayleigh-Plesset equation. It is found that the bubbles will not be generated until a threshold pressure difference is reached. The threshold pressure difference is dependent on the orifice diameter, which determines the time span of pre-formation stage and bubble growth stage.

  16. Mullite fibres preparation by aqueous sol-gel process and activation energy of mullitization

    Energy Technology Data Exchange (ETDEWEB)

    Tan Hongbin, E-mail: hb-t@163.co [State Key Laboratory for Mechanical Behavior of Materials, Xi' an Jiaotong University Xi' an 710049 (China) and School of Materials Science and Engineering, Shaanxi University of Technology, Hanzhong, Shaanxi 723003 (China); Ding Yaping; Yang Jianfeng [State Key Laboratory for Mechanical Behavior of Materials, Xi' an Jiaotong University Xi' an 710049 (China)

    2010-03-04

    Mullite fibres were prepared by sol-gel process using aluminum carboxylates (ACs) and silica sol. ACs was synthesized from dissolving aluminum powder in a mixture of formic acid and oxalic acid using aluminum chloride hexahydrate as catalyst. A molar ratio of 1:2:1 for aluminum, formic acid and oxalic acid was optimized to obtain clear solution and viscous ACs sol for fibres synthesis. Thermogravimetry-differential scanning calorimetry (TG-DSC), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM) analysis were used to characterize the properties of the gel and ceramic fibres. The gel fibres completely transformed to mullite at 1200 {sup o}C, with a smooth surface and uniform diameter. The activation energy for mullite formation in precursor gel fibres was determined by means of differential thermal analysis. The value obtained, E{sub a} = 741.4 kJ/mol, was lower than most data reported in the literatures, which was attributed to the silica-alumina micro-phase separation when organic acids decomposed during gel fibres heating.

  17. Characterization of Ni ferrites powders prepared by plasma arc discharge process

    Science.gov (United States)

    Safari, A.; Gheisari, Kh.; Farbod, M.

    2017-01-01

    The aim of this work was to synthesize a single-phase spinel structure from a mixture of zinc, iron and nickel powders by plasma arc discharge method. A mixture of zinc, iron and nickel powders with the appropriate molar ratio was prepared and formed into a cylindrical shape. The synthesis process was performed in air, oxygen and argon atmospheres with the applied arc current of 400 A and pressure of 1 atm. After establishing an arc between the electrodes, the produced powders were collected and their structure and magnetic properties were examined by XRD and VSM, respectively. ZnO as an impurity was appeared in the as-produced powders owing to the high reactivity of zinc atoms, preventing the formation of Ni-Zn ferrite. A pure spinel structure with the highest saturation magnetization (43.8 emu/g) was observed as zinc powders removed completely from the initial mixture. Morphological evaluations using field emission scanning electron microscopy showed that the mean size of fabricated nanoparticles was in the range 100-200 nm and was dependent on the production conditions.

  18. Biological Processes that Prepare Mammalian Spermatozoa to Interact with an Egg and Fertilize It

    Directory of Open Access Journals (Sweden)

    Daulat R. P. Tulsiani

    2012-01-01

    Full Text Available In the mouse and other mammals studied, including man, ejaculated spermatozoa cannot immediately fertilize an egg. They require a certain period of residence in the female genital tract to become functionally competent cells. As spermatozoa traverse through the female genital tract, they undergo multiple biochemical and physiological changes collectively referred to as capacitation. Only capacitated spermatozoa interact with the extracellular egg coat, the zona pellucida. The tight irreversible binding of the opposite gametes triggers a Ca2+-dependent signal transduction cascade. The net result is the fusion of the sperm plasma membrane and the underlying outer acrosomal membrane at multiple sites that causes the release of acrosomal contents at the site of sperm-egg adhesion. The hydrolytic action of the acrosomal enzymes released, along with the hyperactivated beat pattern of the bound spermatozoon, is important factor that directs the sperm to penetrate the egg coat and fertilize the egg. The sperm capacitation and the induction of the acrosomal reaction are Ca2+-dependent signaling events that have been of wide interest to reproductive biologists for over half a century. In this paper, we intend to discuss data from this and other laboratories that highlight the biological processes which prepare spermatozoa to interact with an egg and fertilize it.

  19. Laser CVD Process for the Preparation of Ultrafine SiC Powder

    Institute of Scientific and Technical Information of China (English)

    ZHANGQitu; XIAODifan

    2000-01-01

    The CW-CO2 laser driven gas reaction was applied to prepare nano-sized SiC powder,SiH4 and C2H4 of high purties,as starting materials,were mixed t a certain ration and introduced into the resaction cell.The gases flew across the laser beam orthogonally and thus were heated by laser beam.The nano-sized SiC ultrafine powderws were formed through thermic gas reation.The final productivity of this process was 97%,The obtained powders were characterized and analyzed.Chemical analysis revealed that the SiC content was 95.38 wt%,Oxygen ,the primary impurity,weighted 1.32% while trace impurities,such as calcium ,magnesium and other metals,were only 0.03%,XRD,XPS and TEM indicated that th powder particles were nearly spherical and not agglomerated.The particle size ranged from 10nm to 25nm with an average of 15 nm ,The particles tred to be noncrystalline.

  20. Structure and mechanical characterization of Mg-Nd-Zn alloys prepared by different processes

    Science.gov (United States)

    Dvorský, D.; Kubásek, J.; Vojtěch, D.; Voňavková, I.; Veselý, M.; Čavojský, M.

    2017-02-01

    Magnesium alloys containing about 3 wt. % of Nd and 0.5 wt. % of Zn are considered as promising materials for application in transport and medical industry. Properly treated materials can reach ultimate tensile strength (UTS) higher than 300 MPa. Also the corrosion resistance of these alloys is superior to many other magnesium-based materials. Present work is focused on the preparation of Mg-3Nd-0.5Zn magnesium alloy by classical casting and subsequent thermal treatment. As-cast material was extruded at 400 °C, with extrusion ratio equal to 16 and velocity of 0.2 mm/s. The effect of thermal treatment and also strong plastic deformation during extrusion on final structure conditions and mechanical properties is specified. Present results confirm significant improvement of tensile yield strength (TYS) and UTS after extrusion process as a consequence of fine-grained structure combined with precipitation strengthening. Beside, texture strengthening in the direction parallel to the extrusion has been observed too.

  1. Low-Latitude Atmosphere-Ionosphere Effects Initiated by Strong Earthquakes Preparation Process

    Directory of Open Access Journals (Sweden)

    Sergey Pulinets

    2012-01-01

    Full Text Available Ionospheric and atmospheric anomalies registered around the time of strong earthquakes in low-latitude regions are reported now regularly. Majority of these reports have the character of case studies without clear physical mechanism proposed. Here we try to present the general conception of low-latitude effects using the results of the recent author’s publications, including also rethinking the earlier results interpreted basing on recently established background physical mechanisms of anomalies generation. It should be underlined that only processes initiated by earthquake preparation are considered. Segregation of low-latitude regions for special consideration is connected with the important role of ionospheric equatorial anomaly in the seismoionospheric coupling and specific character of low-latitude earthquake initiated effects. Three main specific features can be marked in low-latitude ionospheric anomalies manifestation: the presence of magnetic conjugacy in majority of cases, local longitudinal asymmetry of effects observed in ionosphere in relation to the vertical projection of epicenter onto ionosphere, and equatorial anomaly reaction even on earthquakes outside equatorial anomaly (i.e., 30–40 LAT. The equality of effects morphology regardless they observed over land or over sea implies only one possible explanation that these anomalies are initiated by gaseous emanations from the Earth crust, and radon plays the major role.

  2. Tribological Behavior of A356/Al2O3 Surface Nanocomposite Prepared by Friction Stir Processing

    Science.gov (United States)

    Mazaheri, Y.; Karimzadeh, F.; Enayati, M. H.

    2014-04-01

    Surface A356 aluminum alloy matrix composites containing micro and nanosized Al2O3 are prepared by a new approach utilizing high-velocity oxy-fuel spraying and friction stir processing (FSP). Optical and scanning electron microscopy, microhardness, and wear tests were used to characterize the surface composites. Results indicated that, the presence of Al2O3 in matrix can improve the mechanical properties of specimens. The microhardness of surface composites containing micro and nanosized Al2O3 were 89.8 ± 2.6 HV and 109.7 ± 2.5 HV, respectively, which were higher than those for the as-received (79.6 ± 1.1 HV) and the FSPed A356-T6 with no alumina powder (66.8 ± 0.9 HV). Surface composites revealed low friction coefficients and wear rates, which were significantly lower than those obtained for substrate. The wear mass losses of the as-received, the FSPed, and surface micro and nanocomposite specimens after 500-m sliding distance were 50.5, 55.6, 31, and 17.2 mg, respectively. Scanning electron microscopy tests revealed different wear mechanisms on the surface of the wear test specimens.

  3. The MELISSA food data base: space food preparation and process optimization

    Science.gov (United States)

    Creuly, Catherine; Poughon, Laurent; Pons, A.; Farges, Berangere; Dussap, Claude-Gilles

    Life Support Systems have to deal with air, water and food requirement for a crew, waste management and also to the crew's habitability and safety constraints. Food can be provided from stocks (open loops) or produced during the space flight or on an extraterrestrial base (what implies usually a closed loop system). Finally it is admitted that only biological processes can fulfil the food requirement of life support system. Today, only a strictly vegetarian source range is considered, and this is limited to a very small number of crops compared to the variety available on Earth. Despite these constraints, a successful diet should have enough variety in terms of ingredients and recipes and sufficiently high acceptability in terms of acceptance ratings for individual dishes to remain interesting and palatable over a several months period and an adequate level of nutrients commensurate with the space nutritional requirements. In addition to the nutritional aspects, others parameters have to be considered for the pertinent selection of the dishes as energy consumption (for food production and transformation), quantity of generated waste, preparation time, food processes. This work concerns a global approach called MELISSA Food Database to facilitate the cre-ation and the management of these menus associated to the nutritional, mass, energy and time constraints. The MELISSA Food Database is composed of a database (MySQL based) con-taining multiple information among others crew composition, menu, dishes, recipes, plant and nutritional data and of a web interface (PHP based) to interactively access the database and manage its content. In its current version a crew is defined and a 10 days menu scenario can be created using dishes that could be cooked from a set of limited fresh plant assumed to be produced in the life support system. The nutritional covering, waste produced, mass, time and energy requirements are calculated allowing evaluation of the menu scenario and its

  4. Realization basic directions of the Bologna process in preparation of teachers physical cultures in Polish Institutes of higher

    Directory of Open Access Journals (Sweden)

    Pasichnik V.R.

    2010-06-01

    Full Text Available Basic progress of higher school trends are presented in Poland. Directions of introduction of decisions of Bologna declaration and European educational standards are considered in preparation of teachers of physical culture. Information is resulted about the improvement of process of preparation of specialists of physical education and sport in the Warsaw academy of physical education. Growth of the state financing of research projects and introduction of the European educational projects is marked. It renders assistance to perfection of process of training of pedagogical personnels.

  5. Nano Si preparation by constant cell voltage electrolysis of FFC-Cambridge Process in molten CaCl2

    Institute of Scientific and Technical Information of China (English)

    Ji; Zhao; Shengmei; Lu; Linyan; Hu; Can; Li

    2013-01-01

    Using FFC-Cambridge Process to prepare Si from SiO2 is a promising method to prepare nanostructured and highly pure silicon for solar cells.However,the method still has many problems unsolved and the controlling effect of the cell voltage on silicon product is not clear.Here we report in this article that nano cluster-like silicon product with purity of 99.95%has been prepared by complete conversion of raw material SiO2,quartz glass plate,using constant cell voltage electrolysis FFC-Cambridge Process.By analysis of XRD,EDS,TEM,HRTEM and ICP-AES as well as the discussion from the thermodynamics calculation,the morphology and components of the product based on the change of cell voltage are clarified.It is clear that pure silicon could be prepared at the cell voltage of 1.7 2.1 V in this reaction system.The silicon material have cluster-like structure which are made of silicon nanoparticles in 20 100 nm size.Interestingly,the cluster-like nano structure of the silicon can be tuned by the used cell voltage.The purity,yield and the energy cost of silicon product prepared at the optimized cell voltage are discussed.The purity of the silicon product could be further improved,hence this method is promising for the preparation of solar grade silicon in future.

  6. Influence of Process Control Agent on Characterization and Structure of Micron Chitosan Powders Prepared by Ball Milling Method

    Directory of Open Access Journals (Sweden)

    ZHANG Chuan-jie

    2016-12-01

    Full Text Available With ethyl alcohol or distilled water as process control agent (PCA, micron chitosan powder was prepared by ball milling method. The yield rate, particle size distribution, micro morphology, viscosity average molecular mass, chemical and crystal structures, and thermal properties of these different micron chitosan powders were measured. The results indicate that the yield rate of micron chitosan powders prepared with ethyl alcohol as PCA increases significantly, and improves to 94.7% from 25% while the amount of ethyl alcohol is 0.75mL/g. The particle size distribution of micron chitosan powder prepared with ethyl alcohol as PCA is concentrated, while the D50 and D90 in size are 824nm and 1629nm respectively. Chitosan do not react with ethyl alcohol used as PCA, but the viscosity average molecular mass of prepared micron chitosan powder decreases by 23%, the crystal structures are destroyed slightly, and its thermal stability is slightly weakened.

  7. Enhanced bulk heterojunction devices prepared by thermal and solvent vapor annealing processes

    Energy Technology Data Exchange (ETDEWEB)

    Forrest, Stephen R.; Thompson, Mark E.; Wei, Guodan; Wang, Siyi

    2017-09-19

    A method of preparing a bulk heterojunction organic photovoltaic cell through combinations of thermal and solvent vapor annealing are described. Bulk heterojunction films may prepared by known methods such as spin coating, and then exposed to one or more vaporized solvents and thermally annealed in an effort to enhance the crystalline nature of the photoactive materials.

  8. The preparation, processing and properties of thin and thick films for microelectric applications

    Science.gov (United States)

    Bagley, B. G.; Greene, L. H.; Barboux, P.; Tarascon, J. M.; Venkatesan, T.

    High-Tc thin and thick films of YBa2Cu2O(7-y) and thick films based on the Bi-Sr-Ca-Cu and Tl-Ba-Ca-Cu systems were prepared and their properties investigated. It was found that YB2Cu3O(7-y) thin films prepared at temperatures up to 400 C, have amorphous structures, and those prepared in the 400-650 C region exhibit polyphase microstructure, due to the rapid crystallization kinetics of the competing phases. Methods for bipassing the 'forbidden' temperature region are described. Preparation of YBa2Cu2O(7-y) thick films was achieved via an aqueous sol-gel technique. Bi-Sr-Ca-Cu- and Tl-Ba-Ca-Cu-based thick films were prepared via the decomposition of glycerol-based solutions containing nitrates of the elements.

  9. Dynamic simulation on the preparation process of thin films by pulsed laser

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Duanming(

    2001-01-01

    [1]Agostinelli, J. A. , Braunstein, G. H. , Blanton, T. N., Epitaxial LiTaO3 film by pulsed laser ablation, Appl. Phys.Lett., 1993, 63(2): 123-132.[2]Liu, J. M., Zhang, F., Liu, Z. G. et al., Epitaxial growth of optical Ba2NaNb5015 waveguide film by pulsed laser deposition, Appl. Phys. Lett., 1994, 65(16): 1995-2011.[3]Venkatesan, T., Observation of two distinct components during pulsed laser deposition of high Tc superconducting films, Appl. Phys. Lett., 1988, 52(14): 1193-1198.[4]Foltyn, S. R., Tiwari, P., Dye, R. C. et al., Pulsed laser deposition of thick YBa2Cu3O7-x films with Jc> 1MA/cm2, Appl. Phys. Lett., 1993, 63: 1848-1852.[5]Singh, R. K., Narayan, J., Pulsed-laser evaporation technique for deposition of thin films: Physics and theoretical model,Phys. Rev. B., 1990, 41(13): 8843-8859.[6]De Groot, J. S., Estabrook, K. G., Kruer, W. L. et al., Distributed absorption model for moderate to high laser powers,Phys. Fluids B, 1992, 4(3): 701-707.[7]Lu Jian, Ni Xiaown, The Interaction Physics of Laser and Materials (in Chinese), Beijing: Machinery Industry Press, 1996.[8]Fabbro, R., Max, C., Fubre, E., Planar laser-driven ablation: Effect of inhibited electron thermal conduction, Phys. Fluids, 1995, 28(5): 1463-1479.[9]Ozisik, M. N. , Heat Conduction (in Chinese), translated by Yu Changming, Beijing: Higher Education Press, 1984.[10]Eckert, E. R. G. , Drake, R. M. , Jr. , Analysis of Heat and Mass Transfer (in Chinese), translated by Hang Qing, Beijing: Science Press, 1983.[11]Chen Junguo (ed.), High-grade Heat Conduction (in Chinese), Chongqing: Chongqing University Press, 1991.[12]Yu Gang, An Yongqiang, Hu Youjuan et al., The enthalpy-solution method on phase-transfer problem in pulse pure, Chinese Laser Journal (in Chinese), 2000, 27(10): 931-936.[13]Wang Shimin, Zhang Duanming, Dielectric ferroelectric properties of KTN thin films prepared by sol-gel process, Journal of Sol-Gel Science and

  10. Effect of preparation method of metal hydride electrode on efficiency of hydrogen electrosorption process

    Energy Technology Data Exchange (ETDEWEB)

    Giza, Krystyna [Czestochowa University of Technology (Poland). Faculty of Production Engineering and Materials Technology; Drulis, Henryk [Trzebiatowski Institute of Low Temperatures and Structure Research PAS, Wroclaw (Poland)

    2016-02-15

    The preparation of negative electrodes for nickel-metal hydride batteries using LaNi{sub 4.3}Co{sub 0.4}Al{sub 0.3} alloy is presented. The constant current discharge technique is employed to determine the discharge capacity, the exchange current density and the hydrogen diffusion coefficient of the studied electrodes. The electrochemical performance of metal hydride electrode is strongly affected by preparation conditions. The results are compared and the advantages and disadvantages of preparation methods of the electrodes are also discussed.

  11. Integrated coal preparation and CWF processing plant: Conceptual design and costing

    Energy Technology Data Exchange (ETDEWEB)

    McHale, E.T.; Paul, A.D.; Bartis, J.T. (Science Applications International Corp., McLean, VA (United States)); Korkmaz, M. (Roberts and Schaefer Co., Salt Lake City, UT (United States))

    1992-12-01

    At the request of the US Department of Energy (DOE), Pittsburgh Energy Technology Center, a study was conducted to provide DOE with a reliable, documented estimate of the cost of producing coal-water fuel (CWF). The approach to the project was to specify a plant capacity and location, identify and analyze a suitable coal, and develop a conceptual design for an integrated coal preparation and CWF processing plant. Using this information, a definitive costing study was then conducted, on the basis of which an economic and sensitivity analysis was performed utilizing a financial evaluation model to determine a price for CWF in 1992. The design output of the integrated plant is 200 tons of coal (dry basis) per hour. Operating at a capacity factor of 83 percent, the baseline design yields approximately 1.5 million tons per year of coal on a dry basis. This is approximately equivalent to the fuel required to continuously generate 500 MW of electric power. The CWF produced by the plant is intended as a replacement for heavy oil or gas in electric utility and large industrial boilers. The particle size distribution, particularly the top size, and the ash content of the coal in the CWF are specified at significantly lower levels than is commonly found in typical pulverized coal grinds. The particle top size is 125 microns (vs typically 300m[mu] for pulverized coal) and the coal ash content is 3.8 percent. The lower top size is intended to promote complete carbon burnout at less derating in boilers that are not designed for coal firing. The reduced mineral matter content will produce ash of very fine particle size during combustion, which leads to less impaction and reduced fouling of tubes in convective passages.

  12. Integrated coal preparation and CWF processing plant: Conceptual design and costing. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    McHale, E.T.; Paul, A.D.; Bartis, J.T. [Science Applications International Corp., McLean, VA (United States); Korkmaz, M. [Roberts and Schaefer Co., Salt Lake City, UT (United States)

    1992-12-01

    At the request of the US Department of Energy (DOE), Pittsburgh Energy Technology Center, a study was conducted to provide DOE with a reliable, documented estimate of the cost of producing coal-water fuel (CWF). The approach to the project was to specify a plant capacity and location, identify and analyze a suitable coal, and develop a conceptual design for an integrated coal preparation and CWF processing plant. Using this information, a definitive costing study was then conducted, on the basis of which an economic and sensitivity analysis was performed utilizing a financial evaluation model to determine a price for CWF in 1992. The design output of the integrated plant is 200 tons of coal (dry basis) per hour. Operating at a capacity factor of 83 percent, the baseline design yields approximately 1.5 million tons per year of coal on a dry basis. This is approximately equivalent to the fuel required to continuously generate 500 MW of electric power. The CWF produced by the plant is intended as a replacement for heavy oil or gas in electric utility and large industrial boilers. The particle size distribution, particularly the top size, and the ash content of the coal in the CWF are specified at significantly lower levels than is commonly found in typical pulverized coal grinds. The particle top size is 125 microns (vs typically 300m{mu} for pulverized coal) and the coal ash content is 3.8 percent. The lower top size is intended to promote complete carbon burnout at less derating in boilers that are not designed for coal firing. The reduced mineral matter content will produce ash of very fine particle size during combustion, which leads to less impaction and reduced fouling of tubes in convective passages.

  13. Preparation of highly exfoliated polyester-clay nanocomposites: process-property correlations.

    Science.gov (United States)

    Dalir, Hamid; Farahani, Rouhollah D; Nhim, Vireya; Samson, Benjamin; Lévesque, Martin; Therriault, Daniel

    2012-01-10

    A large number of polyester nanocomposite batches featuring different kinds of nanoclay surface modifiers and up to 6 wt % nanoclay were manufactured using a solvent-based technique. Montmorillonite platelets modified with ammonium ions of different chemical architectures were examined to study the effect of ammonium ions on the extent of surface reactions with long-chain fatty acids. The ammonium montmorillonite was first dispersed and suspended in acetone. This suspension was further esterificated with dotriacontanoic (lacceroic) acid to form high density brushes on the clay surface. This led to achieving higher basal plane spacing of the montmorillonite platelets due to the reduction of electrostatic interactions holding them. The outcome of the surface esterification was analyzed by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The esterificated ammonium-modified clays were then mixed by five different mixing strategies based on the use of a three-roll mill mixer (TRM) and/or ultrasonication (US) to obtain the desired polyester-nanoclay dispersion, intercalation, and exfoliation. The dispersion states of the modified nanoclay in polymer were characterized from XRD, scanning electron microscopy (SEM), and low and high magnification transmission electron microscopy (TEM). Mechanical, thermal, and barrier properties of the resulting composites were experimentally characterized. The Mori-Tanaka method along with an orientation distribution function was used to verify the experimental effective stiffness of the polyester nanocomposite systems. The aspect ratio of nanoclays and their level of intercalation and/or exfoliation after mixing were also confirmed by the comparison of the experimental diffusivity results with those of Fick's diffusion model. Systems having 4 and 6 wt % esterificated ammonium nanoclay and prepared according to a combined TRM/US mixing procedure showed optimal performance with balanced properties and processing

  14. Evaluation of dentinal defects during root canal preparation using thermomechanically processed nickel-titanium files.

    Science.gov (United States)

    Kesim, Bertan; Sagsen, Burak; Aslan, Tugrul

    2017-01-01

    The aim of this study was to compare the incidence of root cracks after root canal instrumentation with thermomechanically processed nickel-titanium (Ni-Ti) files with different instrumentation kinematics. A total of 150 extracted mandibular premolars with mature apices and straight root canals were divided into five groups and used in this study. In Group 1, 30 teeth were prepared using hand K-files and assigned to control group, Group 2 was instrumented using K3XF Rotary files (SybronEndo, Glendora, CA, USA) with continuous rotary motion. The teeth in Group 3 were instrumented by ProTaper Next (Dentsply Maillefer, Ballaigues, Switzerland) rotary files which make asymmetric rotary motion, In Group 4, teeth were instrumented by RECIPROC (VDW, Munich, Germany) with reciprocation motion and in Group 5, teeth were instrumented by Twisted File (TF) Adaptive (SybronEndo, Orange, CA, USA) files that use combination of continuous rotation and reciprocation motion (n = 30/per group). All the roots were horizontally sectioned 3, 6, and 9 mm from the apex with a low speed saw under water cooling. Then, the slices were examined through a stereomicroscope to determine the presence of dentinal microcracks. For the apical (3-mm) and coronal (9-mm) sections, the ProTaper Next and TF Adaptive produced significantly more cracks than the hand files, RECIPROC, and K3XF (P 0.05). Within the limitations of this in vitro study, all thermal-treated Ni-Ti instruments and hand files caused microcracks in root canal dentin.

  15. Preparation of GdBCO Thin Film by Ex-situ Process using Nitrate Precursors

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Byeong Joo; Le, Chul Sun; Lee, Jong Beom; Lee, Hee Gyoun; Hong, Gye Won [Korea Polytechnic University, Siheung (Korea, Republic of); Lee, Jae Hun; Moon, Sung Hyun [SuNAM Co., Anseong (Korea, Republic of)

    2011-12-15

    Many research groups have been manufacturing coated conductor by various processes such as PLD, MOD, and MOCVD, but the methods with production cost suitable for wide and massive application of coated conductor did not develop yet. Spray pyrolysis method adopting ultrasonic atomization was tried as one of the possible option. GdBCO precursor films have been deposited on IBAD substrate by spray pyrolysis method at low temperature and converted to GdBCO by post heat treatment. Ultrasonic atomization was used to generate fine droplets from precursor solution of Gd, Ba, and Cu nitrate dissolved in water. Primary GdBCO films were deposited at 500 degree C and oxygen partial pressure of 1 torr. After that, the films were converted at various temperatures and low oxygen partial pressures. C-Axis oriented films were obtained IBAD substrates at conversion temperature of around 870 degree C and oxygen partial pressures of 500 mtorr - 1 torr in a vacuum. Thick c-axis epitaxial film with the thickness of 0.4 - 0.5 {mu}m was obtained on IBAD substrate. C-axis epitaxial GdBCO films were successfully prepared by ex-situ methods using nitrate precursors on IBAD metal substrate. Converted GdBCO films have very dense microstructures with good grain connectivity. EDS composition analysis of the film showed a number of Cu-rich phase in surface. The precursor solution having high copper concent with the composition of Gd : Ba : Cu = 1 : 2 : 4 showed the better grain connectivity and electrical conductivity.

  16. The Preparation of Electronic Assembly Process Planning%电子装配工艺规程的编制

    Institute of Scientific and Technical Information of China (English)

    弥锐

    2011-01-01

    工艺文件是产品生产重要的技术文件之一,本文从企业生产一线工艺的角度论述了工艺文件的两大组成部分、电子产品工艺文件的成套性编制和工艺文件的管理,着重讲述了指导技术操作的工艺文件--工艺规程的编制.%The process file is one of important technical documents of product production. This paper discussed two major components of process documents, the preparation of sets of technical documents and the management of process documents from the point of production line process, highlighted the preparation of technical documents which guide the technical operation.

  17. In situ preparation of hydrophobic CaCO3 nanoparticles in a gas-liquid microdispersion process

    Institute of Scientific and Technical Information of China (English)

    Le Du; Yujun Wang; Guangsheng Luo

    2013-01-01

    This study presents a novel process of in situ surface modification of CaCO3 nanoparticles using a multipleorifice dispersion microreactor.CO2/Ca(OH)2 precipitation reaction was employed to prepare CaCO3 nanoparticles with sodium stearate surfactant.Synthesized CaCO3 products were characterized by thermogravimetric analysis (TGA),infra-red (IR),X-ray diffraction (XRD),transmission electron microscopy (TEM) and Brunauer-Emmet-Teller analysis (BET).The effect of various operation parameters on nanopartides and the dosage of sodium stearate were determined.The results showed that the preparation process could be precisely controlled with efficient mass transfer process.The particles were highly hydrophobic with a contact angle of 117° and monodisperse with an average size of 30 nm.The adsorptions of sodium stearate and calcium ion on solid particles during the in situ surface modification process were investigated.

  18. 77 FR 1707 - National Toxicology Program (NTP) Final Process for Preparation of the Report on Carcinogens (RoC)

    Science.gov (United States)

    2012-01-11

    ... HUMAN SERVICES National Institutes of Health National Toxicology Program (NTP) Final Process for Preparation of the Report on Carcinogens (RoC) AGENCY: Division of the National Toxicology Program (DNTP...: December 21, 2011. John R. Bucher, Associate Director, National Toxicology Program. BILLING CODE 4140-01-P...

  19. Handbook Preparation as a Tool for Self-Directed Learning Process: A Case Study on Endocrine Topic

    Science.gov (United States)

    Cerrah Ozsevgec, Lale; Ayas, Alipasa; Ozsevgec, Tuncay

    2010-01-01

    This study examines the effectiveness of handbook preparation as a method in the self-directed learning process of student teachers in teaching endocrine glands, and increasing their levels of knowledge. Thirty student teachers were selected from a biology department. A pencil and paper test and a clinical interview procedure were used to collect…

  20. Procedure for obtaining an extract rich in triterpenic acids from solutions from the process of preparation of table olives

    OpenAIRE

    2008-01-01

    [EN] Procedure for obtaining an extract having a high proportion of triterpenic acids, preferably of oleanolic and maslinic acids, from the solutions obtained in the process of preparation of table olives. Furthermore the invention refers to the extract obtained through said procedure and to application thereof in the food, cosmetic or pharmaceutical industries.

  1. SYSTEM OF CONTROL AND MANAGEMENT OF THE PROCESS OF THE MORTAR SLURRY PREPARATION

    Directory of Open Access Journals (Sweden)

    D. M. Kukuj

    2007-01-01

    Full Text Available The technological schema of automatic flow line allowing to prepare with minimum charges of manual labor the refined from solid additives mortar slurry with stable density is presented in the article.

  2. [Impact of formulation and process parameters on the properties of chitosan-based microspheres prepared by external ionic gelation].

    Science.gov (United States)

    Kubánková, Romana; Vysloužil, Jakub; Kejdušová, Martina; Vetchý, David; Dvořáčková, Kateřina

    2014-06-01

    The aim of this experimental study was to optimize a preparation of microspheres from high viscosity chitosan by external ion gelation and to evaluate selected aspects of their preparation. For drug-free microparticles, the concentration of chitosan dispersions was chosen as a formulation variable; the position of instrument for a dispersion extrusion (horizontal vs. vertical) was evaluated as a process variable. On the basis of sphericity and equivalent diameter results, three different concentrations of chitosan dispersions were used for 5-aminosalicylic acid (5-ASA) encapsulation with the extrusion instrument in horizontal position, which was considered as the optimal. In consequent drug-loaded microparticle preparation, the influence of the concentration of chitosan dispersions and composition of hardening solution (10% sodium tripolyphosphate (TPP) vs. 10% TPP containing drug) was evaluated. In prepared 5-ASA microspheres it was found that the equivalent diameter increased with increasing chitosan concentration. In the case of sphericity, significant differences were not found. Samples prepared with the drug in both chitosan dispersion and hardening solution had a higher drug content, a smaller equivalent diameter and they showed a faster in vitro drug release in comparison with the samples prepared with the drug in chitosan dispersion only.

  3. Reliability of chemotherapy preparation processes: Evaluating independent double-checking and computer-assisted gravimetric control.

    Science.gov (United States)

    Carrez, Laurent; Bouchoud, Lucie; Fleury-Souverain, Sandrine; Combescure, Christophe; Falaschi, Ludivine; Sadeghipour, Farshid; Bonnabry, Pascal

    2017-03-01

    Background and objectives Centralized chemotherapy preparation units have established systematic strategies to avoid errors. Our work aimed to evaluate the accuracy of manual preparations associated with different control methods. Method A simulation study in an operational setting used phenylephrine and lidocaine as markers. Each operator prepared syringes that were controlled using a different method during each of three sessions (no control, visual double-checking, and gravimetric control). Eight reconstitutions and dilutions were prepared in each session, with variable doses and volumes, using different concentrations of stock solutions. Results were analyzed according to qualitative (choice of stock solution) and quantitative criteria (accurate, 30% deviation). Results Eleven operators carried out 19 sessions. No final preparation (n = 438) contained a wrong drug. The protocol involving no control failed to detect 1 of 3 dose errors made and double-checking failed to detect 3 of 7 dose errors. The gravimetric control method detected all 5 out of 5 dose errors. The accuracy of the doses measured was equivalent across the control methods ( p = 0.63 Kruskal-Wallis). The final preparations ranged from 58% to 60% accurate, 25% to 27% weakly accurate, 14% to 17% inaccurate and 0.9% wrong. A high variability was observed between operators. Discussion Gravimetric control was the only method able to detect all dose errors, but it did not improve dose accuracy. A dose accuracy with <5% deviation cannot always be guaranteed using manual production. Automation should be considered in the future.

  4. Preparation of ion-exchange thin film using plasma processes. Plasma process wo mochiita ion kokansei usumaku no sakusei

    Energy Technology Data Exchange (ETDEWEB)

    Ogumi, Z.; Uchimoto, Y. (Kyoto University, Kyoto (Japan). Faculty of Engineering)

    1992-10-31

    The present report describes a study which aims at preparation of a new functional film by plasma polymerization. For this purpose, 4-vinylpyridine monomer is plasma-polymerized to obtain a thin film, which is quaternarized with 1-bromopropane to produce an anion exchange thin film, which is laminated on the surface of a cation-exchange film to make a mono-valent cation perm-selective film. In plasma-polymerization, the relations of polymerizing pressure, as parameter, to the deposition rate of the polymerizerd film and the characteristics of compound were clarified. In preparing the anion-exchange thin film, the preparation of uniform ultrathin films with no pinhole was attempted. For this purpose, the transference number of Cl[sup -] was measured so as to confirm that Cl[sup -] is uniformly distributed and fixed cation groups are distributed uniformly in the film. The perm-selective film exhibited a high mono-valent cation perm-selectivity while its film resistance was increased. This increase is found to be broken down to the resistance of the plasma-polymerization film layer and the resistance of the film interface. The latter arises from the implantation of nitrogen-cointaining species in the plasma onto the surface of the cation exchange film. 26 refs., 10 figs., 2 tabs.

  5. Preparation process for implantation of the quality management system: study of the difficulties from viewpoint of quality management department staff

    Directory of Open Access Journals (Sweden)

    Jaiane Aparecida Pereira

    2016-11-01

    Full Text Available Based on the need for continuous improvement by companies to differentiate themselves against competitors and provide reliability to customers, quality management systems prove to be a valuable tool. However, the preparation process for their implementation is extensive and presents some difficulties. The aim of this research was therefore to understand the difficulties faced by the Quality Management Departament staff during the preparation process for implementing a quality management system at a distributor of electrical products. A qualitative study was developed, using participatory and documentary research. The results showed a difficulty at each step that should be worked on in due time for successful implementation. The main difficulty was the resistance to change by employees, a factor that tends to persist, demanding regular awareness training. In addition, investments showed a need to adapt and improve processes, with it being necessary to assess the advantages of the system in order to prove its viability.

  6. Preparation of MCM-41 in Industrial Scale and Its Application in Heavy Oil Processing

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A series of MCM-41 molecular sieves have been prepared on an industrial scale, and the effect of preparation factors such as aging temperature, pH values on the structure and pore distribution of the MCM-41 product have been studied by using X-ray diffraction(XRD), thermogravimetric(TG) and electron microscopy (TEM). It is shown that the pH values have a significant effect on the crystallinity of the synthesized product. Under proper conditions, the MCM-41 prepared on an industrial scale has the same performance as the samples prepared on an Lab-scale. The prepared MCM-41 was used as a modifier of zeolite Y for fluid catalytic cracking (FCC) of residual oil. It is shown that the addition of the MCM-41 in the zeolite Y catalyst increases the pore size, and surface area of the catalysts, which helps to increase the yield of gasoline and diesel and decrease the production of gaseous product and carbon deposition in the catalyst. The better performance of the MCM-41 modified zeolite Y catalyst is believed to be due to its adjustment on the acidity and increase of the pore size.

  7. Comparison of the two cerebral hemispheres in inhibitory processes operative during movement preparation.

    Science.gov (United States)

    Klein, Pierre-Alexandre; Duque, Julie; Labruna, Ludovica; Ivry, Richard B

    2016-01-15

    Neuroimaging and neuropsychological studies suggest that in right-handed individuals, the left hemisphere plays a dominant role in praxis, relative to the right hemisphere. However hemispheric asymmetries assessed with transcranial magnetic stimulation (TMS) has not shown consistent differences in corticospinal (CS) excitability of the two hemispheres during movements. In the current study, we systematically explored hemispheric asymmetries in inhibitory processes that are manifest during movement preparation and initiation. Single-pulse TMS was applied over the left or right primary motor cortex (M1LEFT and M1RIGHT, respectively) to elicit motor-evoked potentials (MEPs) in the contralateral hand while participants performed a two-choice reaction time task requiring a cued movement of the left or right index finger. In Experiments 1 and 2, TMS probes were obtained during a delay period following the presentation of the preparatory cue that provided partial or full information about the required response. MEPs were suppressed relative to baseline regardless of whether they were elicited in a cued or uncued hand. Importantly, the magnitude of these inhibitory changes in CS excitability was similar when TMS was applied over M1LEFT or M1RIGHT, irrespective of the amount of information carried by the preparatory cue. In Experiment 3, there was no preparatory cue and TMS was applied at various time points after the imperative signal. When CS excitability was probed in the cued effector, MEPs were initially inhibited and then rose across the reaction time interval. This function was similar for M1LEFT and M1RIGHT TMS. When CS excitability was probed in the uncued effector, MEPs remained inhibited throughout the RT interval. However, MEPs in right FDI became more inhibited during selection and initiation of a left hand movement, whereas MEPs in left FDI remained relatively invariant across RT interval for the right hand. In addition to these task-specific effects, there

  8. Bhanupaka: A Green Process in the Preparation of an Indian Ayurvedic Medicine, Lauha Bhasma

    Directory of Open Access Journals (Sweden)

    Balaji Krishnamachary

    2013-01-01

    Full Text Available The use of lauha bhasma, a traditional Indian herbometallic preparation, is in vogue for centuries for the treatment of various ailments related to iron deficiency. The preparation of lauha bhasma requires strict adherence to time-consuming, well-practiced, multistage, and multistep procedures. One of the steps is the treatment of purified metallic ingredients with Triphala decoction (the aqueous extract of Indian gooseberry, Chebulic myrobalans, and Beleric myrobalans in the presence of sunlight (Bhanupaka. The formation of metal complexes due to the reaction of the metallic ingredients with the constituents of Triphala decoction has been ascertained by FTIR spectroscopy and carbon, hydrogen, and nitrogen analyses. Our results demonstrate that Bhanupaka is an essential step in the preparation of lauha bhasma.

  9. Hydrogenolysis of Glycerol to Propylene Glycol on Nanosized Cu-Zn-Al Catalysts Prepared Using Microwave Process.

    Science.gov (United States)

    Kim, Dong Won; Ha, Sang Ho; Moon, Myung Jun; Lim, Kwon Taek; Ryu, Young Bok; Lee, Sun Do; Lee, Man Sig; Hong, Seong-Soo

    2015-01-01

    Cu-Zn-Al catalysts were prepared using microwave-assisted process and co-precipitation methods. The prepared catalysts were characterized by XRD, BET, XPS and TPD of ammonia and their catalytic activity for the hydrogenolysis of glycerol to propylene glycol was also examined. The XRD patterns of Cu/Zn/Al mixed catalysts show CuO and ZnO crystalline phase regardless of preparation method. The highest glycerol hydrogenolysis conversion is obtained with the catalyst having a Cu/Zn/Al ratio of 2:2:1. Hydrogen pre-reduction of catalysts significantly enhanced both glycerol conversions and selectivity to propylene glycol. The glycerol conversion increased with an increase of reaction temperature. However, the selectivity to propylene glycol increased with an increase of temperature, and then declined to 30.5% at 523 K.

  10. [Preparation of the first draft of environmental health criteria for acetonitrile: production process of the draft].

    Science.gov (United States)

    Morimoto, K; Saitoh, M; Hemmi, A; Yamamoto, M; Kaminuma, T

    1992-01-01

    Acetonitrile is a high-polarity aprotic organic solvent used in DNA synthesizers, HPLC, and electrochemistry. In addition, it is used larger amounts at petrochemical companies and pharmaceutical firms. Preparation of an Environmental Health Criteria (EHC) monograph for acetonitrile was started in 1986, and its first draft except the environmental section was completed on June 21, 1991. The environmental section has been prepared by Dr. S. Dobson (ITE/UK). The first draft was circulated to EHC Contact Points for comment in March 1992.

  11. Preparation of continuous alumina gel fibres by aqueous sol–gel process

    Indian Academy of Sciences (India)

    Hongbin Tan; Xiaoling Ma; Mingxing Fu

    2013-02-01

    Continuous alumina gel fibres were prepared by sol–gel method. The spinning sol was prepared by mixing aluminum nitrate, lactic acid and polyvinylpyrrolidone with a mass ratio of 10:3:1.5. Thermogravimetry–differential scanning calorimetry (TG–DSC), Fourier transform infrared (FTIR) spectra, X-ray diffraction (XRD), and scanning electron microscopy (SEM) were used to characterize the properties of the gel and ceramic fibres. The Al2O3 fibres with a uniform diameter can be obtained by sintering gel fibres at 1200 °C.

  12. Optimized spray drying process for preparation of one-step calcium-alginate gel microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Popeski-Dimovski, Riste [Department of physic, Faculty of Natural Sciences and Mathematics, “ss. Cyril and Methodius” University, Arhimedova 3, 1000 Skopje, R. Macedonia (Macedonia, The Former Yugoslav Republic of)

    2016-03-25

    Calcium-alginate micro particles have been used extensively in drug delivery systems. Therefore we establish a one-step method for preparation of internally gelated micro particles with spherical shape and narrow size distribution. We use four types of alginate with different G/M ratio and molar weight. The size of the particles is measured using light diffraction and scanning electron microscopy. Measurements showed that with this method, micro particles with size distribution around 4 micrometers can be prepared, and SEM imaging showed that those particles are spherical in shape.

  13. The influence of the cavity preparation design on marginal accuracy of laboratory-processed resin composite restorations.

    Science.gov (United States)

    Fonseca, Rodrigo Borges; Correr-Sobrinho, Lourenço; Fernandes-Neto, Alfredo Júlio; Quagliatto, Paulo Sérgio; Soares, Carlos José

    2008-03-01

    The aim of this study was to evaluate the influence of different cavity preparation designs on marginal accuracy of laboratory-processed resin composite restored teeth. Eighty mandibular human third molars were selected. There were two experimental factors, occlusal isthmus width (narrow vs wide) and cuspal coverage (inlay, one-cusp onlay, two-cusp onlay, and all-cusp onlay), resulting on eight groups (N = 10). Indirect composite restorations (SR Adoro, Ivoclar-Vivadent) were manufactured and positioned over each respective preparation. Marginal accuracy evaluation was accomplished using a stereomicroscope at three points on buccal, lingual, mesial, and distal regions with 40x magnification. The results showed significant differences (P = 0.00) with wide inlay showing the best overall marginal accuracy and narrow inlay the worst one. Two-way analysis of variance (ANOVA) showed significant differences when considering the factor occlusal isthmus width (P = 0.00). In general, preparations with wide occlusal isthmus presented better results than narrow ones, except for wide all-cusp onlays; however, the test failed to show differences when considering the cuspal coverage (P = 0.42) or the interaction between both factors (P = 0.30). The effect of occlusal width extension on marginal accuracy of indirect composite resin restorations is significant, with lower values of gaps width in wide preparations, but since in a clinical situation this would mean greater removal of sound tooth structure, less-aggressive preparations combined with other restorative procedures seem to be more feasible.

  14. Mechanistic study of the influence of pyrolysis conditions on potassium speciation in biochar "preparation-application" process.

    Science.gov (United States)

    Tan, Zhongxin; Liu, Liyun; Zhang, Limei; Huang, Qiaoyun

    2017-12-01

    Biochar samples produced from rice straw by pyrolysis at different temperatures (400°C and 800°C) and under different atmospheres (N2 and CO2) were applied to lettuce growth in a 'preparation-application' system. The conversion of potassium in the prepared biochar and the effect of the temperature used for pyrolysis on the bioavailability of potassium in the biochar were investigated. Root samples from lettuce plants grown with and without application of biochar were assayed by X-ray photoelectron spectroscopy (XPS). The optimal conditions for preparation of biochar to achieve the maximum bioavailability of potassium (i.e. for returning biochar to soil) were thus determined. Complex-K, a stable speciation of potassium in rice straw, was transformed into potassium sulfate, potassium nitrate, potassium nitrite, and potassium chloride after oxygen-limited pyrolysis. The aforementioned ionic-state potassium species can be directly absorbed and used by plants. Decomposition of the stable speciation of potassium during the pyrolysis process was more effective at higher temperature, whereas the pyrolysis atmosphere (CO2 and N2) had little effect on the quality of the biochar. Based on the potassium speciation in the biochar, the preparation cost, and the plant growth and rigor after the application of returning biochar to soil, 400°C and CO2 atmosphere were the most appropriate conditions for preparation of biochar. Copyright © 2017. Published by Elsevier B.V.

  15. Plasma processes in the preparation of lithium-ion battery electrodes and separators

    Science.gov (United States)

    Nava-Avendaño, J.; Veilleux, J.

    2017-04-01

    Lithium-ion batteries (LIBs) are the energy storage devices that dominate the portable electronic market. They are now also considered and used for electric vehicles and are foreseen to enable the smart grid. Preparing batteries with high energy and power densities, elevated cycleability and improved safety could be achieved by controlling the microstructure of the electrode materials and the interaction they have with the electrolyte over the working potential window. Selecting appropriate precursors, reducing the preparation steps and selecting more efficient synthesis methods could also significantly reduce the costs of LIB components. Implementing plasma technologies can represent a high capital investment, but the versatility of the technologies allows the preparation of powdered nanoparticles with different morphologies, as well as with carbon and metal oxide coatings. Plasma technologies can also enable the preparation of binder-free thin films and coatings for LIB electrodes, and the treatment of polymeric membranes to be used as separators. This review paper aims at highlighting the different thermal and non-thermal plasma technologies recently used to synthesize coated and non-coated active materials for LIB cathodes and anodes, and to modify the surface of separators.

  16. Copper zinc tin sulfide layers prepared from solution processable metal dithiocarbamate precursors

    Energy Technology Data Exchange (ETDEWEB)

    Edler, Michael [Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz (Austria); Christian Doppler Laboratory for Nanocomposite Solar Cells, Graz University of Technology and NanoTecCenter Weiz, Forschungsgesellschaft mbH (Austria); Rath, Thomas, E-mail: thomas.rath@tugraz.at [Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz (Austria); Christian Doppler Laboratory for Nanocomposite Solar Cells, Graz University of Technology and NanoTecCenter Weiz, Forschungsgesellschaft mbH (Austria); Schenk, Alexander [Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz (Austria); Fischereder, Achim [Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz (Austria); Christian Doppler Laboratory for Nanocomposite Solar Cells, Graz University of Technology and NanoTecCenter Weiz, Forschungsgesellschaft mbH (Austria); Haas, Wernfried [Christian Doppler Laboratory for Nanocomposite Solar Cells, Graz University of Technology and NanoTecCenter Weiz, Forschungsgesellschaft mbH (Austria); Institute for Electron Microscopy and Fine Structure Research, Graz University of Technology, Steyrergasse 17, 8010 Graz (Austria); Edler, Matthias [Chair of Chemistry of Polymeric Materials, University of Leoben, Otto Gloeckel-Strasse 2, 8700 Leoben (Austria); Chernev, Boril [Institute for Electron Microscopy and Fine Structure Research, Graz University of Technology, Steyrergasse 17, 8010 Graz (Austria); Kunert, Birgit [Institute of Solid State Physics, Graz University of Technology, Petersgasse 16, 8010 Graz (Austria); Hofer, Ferdinand [Institute for Electron Microscopy and Fine Structure Research, Graz University of Technology, Steyrergasse 17, 8010 Graz (Austria); and others

    2012-10-15

    In this contribution we present a solution based route toward copper zinc tin sulfide - CZTS - layers using metal dithiocarbamate precursors. We focus on the synthesis of the precursor materials as well as on the fabrication of thin CZTS layers at low temperatures of 350 Degree-Sign C and their characterization. Powder X-ray diffraction measurements show that a precursor solution containing an excess of the zinc precursor, compared to the Cu and Sn precursors, has to be used to obtain CZTS films without secondary phases. Thus, the prepared films are Zn-rich, which is beneficial for solar cell applications. Raman as well as X-ray photoelectron spectroscopy studies confirm the formation of CTZS. No clear evidence for free ZnS has been found. Electron microscopy shows agglomerates of 10 nm-sized crystallites forming spherical particles with a diameter between 50 nm and 400 nm. The prepared films possess high optical absorption (>1.10{sup 4} cm{sup -1}) and an optical band gap of approximately 1.6 eV. Highlights: Black-Right-Pointing-Pointer CZTS layers are prepared from metal dithiocarbamate precursor solu-tions. Black-Right-Pointing-Pointer No additional sulfur sources or capping agents are necessary. Black-Right-Pointing-Pointer Prepared CZTS layers are zinc rich. Black-Right-Pointing-Pointer CZTS layers show a high absorption coefficient and a band gap of 1.6 eV.

  17. Preparing Instructional Designers for Game-Based Learning: Part III. Game Design as a Collaborative Process

    Science.gov (United States)

    Hirumi, Atsusi; Appelman, Bob; Rieber, Lloyd; Van Eck, Richard

    2010-01-01

    In this three part series, four professors who teach graduate level courses on the design of instructional video games discuss their perspectives on preparing instructional designers to optimize game-based learning. Part I set the context for the series and one of four panelists discussed what he believes instructional designers should know about…

  18. A review of state-of-the-art processing operations in coal preparation

    Institute of Scientific and Technical Information of China (English)

    Noble Aaron; Luttrell Gerald H.

    2015-01-01

    Coal preparation is an integral part of the coal commodity supply chain. This stage of post-mining, pre-utilization beneficiation uses low-cost separation technologies to remove unwanted mineral matter and moisture which hinder the value of the coal product. Coal preparation plants typically employ several parallel circuits of cleaning and dewatering operations, with each circuit designed to optimally treat a specific size range of coal. Recent innovations in coal preparation have increased the efficiency and capac-ity of individual unit operations while reinforcing the standard parallel cleaning approach. This article, which describes the historical influences and state-of-the-art design for the various coal preparation unit operations, is organized to distinguish between coarse/intermediate coal cleaning and fine/ultrafine coal cleaning. Size reduction, screening, classification, cleaning, dewatering, waste disposal unit operations are particularly highlighted, with a special focus on the U.S. design philosophy. Notable differences between the U.S. and international operations are described as appropriate.

  19. Simulation: Pre-briefing Preparation, Clinical Judgment and Reflective Process. What is the connection?

    Directory of Open Access Journals (Sweden)

    Leighsa Sharoff

    2015-06-01

    Instructors felt more confident and prepared after reading the preparatory material. Conclusions: Clear link between pre-briefing preparatory simulation material, clinical judgment and reflective practice. It is important that both students and instructors are comfortable with the inclusion of simulation as a teaching strategy. [J Contemp Med 2015; 5(2.000: 88-101

  20. Preparation of gas-tight strontium-doped lanthanum cobaltate by an aqueous sol-gel process

    NARCIS (Netherlands)

    Chen, C.H.; Kruidhof, H.; Bouwmeester, H.J.M.; Burggraaf, A.J.

    1996-01-01

    Gas-tight dense membranes of highly Sr-doped LaCoO3 (such as the composition La0.3Sr0.7CoO3 chosen in this study) are difficult to prepare using usual synthesis processes. This report presents an aqueous sol-gel route using metal acetates as precursors to achieve this goal. Hydrogen peroxide and amm

  1. Pt-Ru Catalysts Prepared by a Modified Polyol Process for Direct Methanol Fuel Cells

    Institute of Scientific and Technical Information of China (English)

    ZHANG Junmin; ZHU Fangfang; ZHANG Kunhua; LIU Weiping; GUAN Weiming

    2012-01-01

    Supported PtRu/C catalysts used in direct methanol fuel cells (DMFCs) were prepared by a new modified polyol method.Transmission electron microscopy (TEM),X-ray diffraction (XRD) and cyclic voltammograms (CVs) were carried out to characterize the morphology,composition and the electrochemical properties of the PtRu/C catalyst.The results revealed that the PtRu nanoparticles with small average particle size (≈2.5 nm),and highly dispersed on the carbon support.The PtRu/C catalyst exhibited high catalytic activity and anti-poisoned performance than that of the JM PtRu/C.It is imply that the modified polyol method is efficient for PtRu/C catalyst preparation.

  2. Microwave processing: A potential technique for preparing NiO–YSZ composite and Ni–YSZ cermet

    Indian Academy of Sciences (India)

    Kanchan Lata Singh; Ajay Kumar; Anirudh P Singh; S S Sekhon

    2008-08-01

    In the present study, microwave energy (2.45 GHz) has been used to prepare nickel oxide–yttria stabilized zirconia (NiO–YSZ) composites of composition, NiO–(1 – ) Zr0.9Y0.1O1.95 ( = 0.2, 0.3, 0.4, 0.5 and 0.6), from a precursor obtained by mixing NiO, Y2O3 and monoclinic ZrO2 in their stoichiometric ratio. The composites have been prepared by conventional processing also to compare the products with those of microwave processed products. During comparison, it was observed that NiO–YSZ composites of each composition obtained by microwave processing had cubic phase of YSZ while in the conventionally prepared composites of compositions, = 0.2 and 0.3, monoclinic, tetragonal and cubic phases of zirconia existed instead of its pure cubic phase. The composites were reduced to yield Ni–YSZ.

  3. A novel recovery method of copper from waste printed circuit boards by supercritical methanol process: Preparation of ultrafine copper materials.

    Science.gov (United States)

    Xiu, Fu-Rong; Weng, Huiwei; Qi, Yingying; Yu, Gending; Zhang, Zhigang; Zhang, Fu-Shen; Chen, Mengjun

    2017-02-01

    In this study, supercritical methanol (SCM) process was successfully used for the preparation of ultrafine copper materials from waste printed circuit boards (PCBs) after nitric acid pretreatment. Waste PCBs were pretreated twice in nitric acid. Sn and Pb were recovered by the first nitric acid pretreatment. The leach liquor with a high concentration of copper ions after the second nitric acid leaching was subjected to SCM process. The mixture of Cu and Cu2O with poor uniformity of particle size was formed due to the effect of ferric iron contained in the leach liquor of waste PCBs, while more uniform and spherical Cu particles with high monodispersity and smaller size could be prepared after the removal of Fe. The size of Cu particles increased obviously with the decline of SCM temperature, and particles became highly aggregated when the reaction temperature decreased to 300°C. The size of Cu particles decreased markedly with the decrease of initial concentration of copper ion in the leach liquor of waste PCBs. It is believed that the process developed in this study is simple and practical for the preparation of ultrafine copper materials from waste PCBs with the aim of recycling these waste resources as a high value-added product. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Variations in polyethylene glycol brands and their influence on the preparation process of hydrogel microspheres

    DEFF Research Database (Denmark)

    Wöhl-Bruhn, Stefanie; Bertz, Andreas; Kuntsche, Judith

    2013-01-01

    Hydrogel microspheres, e.g. for the use as protein carriers, can be prepared without the use of organic solvents via an emulsified aqueous two phase system (ATPS) that is based on two immiscible polymer solutions. The type and concentration of the polymers can affect the ATPS and finally the dist......Hydrogel microspheres, e.g. for the use as protein carriers, can be prepared without the use of organic solvents via an emulsified aqueous two phase system (ATPS) that is based on two immiscible polymer solutions. The type and concentration of the polymers can affect the ATPS and finally...... the distribution of incorporated drugs between the aqueous phases. For the preparation of hydrogel microspheres based on hydroxyethyl starch-hydroxyethyl methacrylate (HES-HEMA), hydroxyethyl starch-methacrylate (HES-MA), and hydroxyethyl starch-polyethylene glycol methacrylate (HES-P(EG)6MA), polyethylene glycol...... 12,000 (PEG 12,000) was used as second polymer. The particle size distribution and encapsulation efficiency of the microspheres depended dramatically on the type of PEG 12,000 that was used in the second phase of the ATPS. Analysis of different PEG 12,000 brands by various methods revealed...

  5. Synthesis of strontium hexaferrite nanoparticles prepared using co-precipitation method and microemulsion processing

    Science.gov (United States)

    Drmota, A.; Žnidaršič, A.; Košak, A.

    2010-01-01

    Strontium hexaferrite (SrFe12O19) nanoparticles have been prepared with co-precipitation in aqueous solutions and precipitation in microemulsion system water/SDS/n-butanol/cyclohexane, using iron and strontium nitrates in different molar rations as a starting materials. The mixed Sr2+, Fe3+ hydroxide precursors obtained during the reaction between corresponding metal nitrates and tetramethylammonium hydroxide (TMAH), which served as a precipitating reagent, were calcined in a wide temperature range, from 350 °C to 1000 °C in a static air atmosphere. The influence of the Sr2+/Fe3+ molar ratio and the calcination temperature to the chemistry of the product formation, its crystallite size, morphology and magnetic properties were investigated. It was found that the formation of single phase SrFe12O19 with relatively high specific magnetization (54 Am2/kg) was achieved at the Sr2+/Fe3+ molar ration of 6.4 and calcination at 800 °C for 3h with heating/cooling rate 5 °C/min. The prepared powders were characterized using X-ray diffractometry (XRD) and specific surface area measurements (BET). The specific magnetization (DSM-10, magneto-susceptometer) of the prepared samples was measured.

  6. Preparation of hydroxyapatite nanoparticles by sol-gel method with optimum processing parameters

    Energy Technology Data Exchange (ETDEWEB)

    Yusoff, Yusriha Mohd; Salimi, Midhat Nabil Ahmad; Anuar, Adilah [Universiti Malaysia Perlis, Kompleks Pusat Pengajian Jejawi 3, 02600 Arau, Perlis (Malaysia)

    2015-05-15

    Many studies have been carried out in order to prepare hydroxyapatite (HAp) by various methods. In this study, we focused on the preparation of HAp nanoparticles by using sol-gel technique in which few parameters are optimized which were stirring rate, aging time and sintering temperature. HAp nanoparticles were prepared by using precursors of calcium nitrate tetrahydrate, Ca(NO{sub 3}){sub 2}.4H{sub 2}O and phosphorous pentoxide, P{sub 2}O{sub 5}. Both precursors are mixed in ethanol respectively before they were mixed together in which it formed a stable sol. Fourier transform infrared (FTIR), X-ray diffraction (XRD) and Scanning electron microscopy (SEM) were used for its characterization in terms of functional group, phase composition, crystallite size and morphology of the nanoparticles produced. FTIR spectra showed that the functional groups that present in all five samples were corresponding to the formation of HAp. Besides, XRD shows that only one phase was formed which was hydroxyapatite. Meanwhile, SEM shows that the small particles combine together to form agglomeration.

  7. Non isothermal decomposition of lanthanum titanates precursors prepared by sol gel process: A kinetic and thermodynamic study

    Energy Technology Data Exchange (ETDEWEB)

    Bassil, S. [Université Lyon 1, CNRS, UMR 5256, IRCELYON, Institut de recherches sur la catalyse et l’environnement de Lyon, 2 avenue Albert Einstein, F-69626 Villeurbanne (France); Kaddouri, A., E-mail: akim.kaddouri@ircelyon.univ-lyon1.fr [Université Lyon 1, CNRS, UMR 5256, IRCELYON, Institut de recherches sur la catalyse et l’environnement de Lyon, 2 avenue Albert Einstein, F-69626 Villeurbanne (France); Béguin, B.; Gélin, P. [Université Lyon 1, CNRS, UMR 5256, IRCELYON, Institut de recherches sur la catalyse et l’environnement de Lyon, 2 avenue Albert Einstein, F-69626 Villeurbanne (France)

    2013-09-10

    Highlights: ► Metal-propionates is a most promising route for the preparation of La{sub 0.8}Sr{sub 0.2}TiO{sub 3+δ} (LST) at a temperature substantially lower than that used for the preparation of the same solid by traditional methods. ► Activation energy and isothermal thermodynamic parameters calculated for the decomposition process are close to those observed for metal organic compounds. ► Sol gel-prepared LST presented low propensity to coke deposition and high stability with time during the critical long term exposure to methane and steam at high temperatures. - Abstract: The single phase La{sub 0.8}Sr{sub 0.2}TiO{sub 3+δ} was prepared via the sol gel process using propionic acid. Kinetics of the thermal decomposition of the precursors has been studied using differential thermogravimetry under non-isothermal conditions in different atmospheres (air and helium). Non isothermal kinetic (A and ΔE) and thermodynamic parameters (ΔH, ΔS and Cp) were determined using different heating rates. La{sub 2}O{sub 3}, SrO and TiO{sub 2} products crystallized at temperatures of ca. 730, 960 and 470 °C respectively while pure La{sub 0.8}Sr{sub 0.2}TiO{sub 3+δ} phase was obtained at 1200 °C, temperature substantially lower than that used for the preparation of La{sub 0.8}Sr{sub 0.2}TiO{sub 3+δ} by conventional solid state method. Precursors and/or final solids were characterized by thermogravimetric analysis (TG), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction, diffuse reflectance ultraviolet–visible spectroscopy (DR-UV–vis) and methane steam reforming under water deficient conditions.

  8. Axiological approach in the process of professionally - pedagogical preparation of future teachers of physical education [Aksiologicheskij podkhod v processe professional'no- pedagogicheskoj podgotovki budushchikh uchitelej fizicheskogo vospitaniia

    Directory of Open Access Journals (Sweden)

    Deminskaya L.A.

    2011-11-01

    Full Text Available It is considered humanism principles of the modern system of education based on the axiological approach near pedagogical process. The analysis of publications is conducted on questions of maintenance and realization of axiological approach in the field of trade pedagogical education. It is set that axiological approach in the process of professional-pedagogical preparation of future teachers is oriented to forming of the system of pedagogical values and values of physical education. Such valued orientations answer the requirements of modern teacher of physical education.

  9. Mechanized methods for preparation and processing of compost from pruning residues in fruit-vine production

    OpenAIRE

    2011-01-01

    This paper is part of research about the effects of mechanized process of fragmentation of pruning residues on the composting process. Compost, as a form of organic fertilizer, requires specific production treatment depending on the form of biomass. Pruning residues from fruit-vine production can be translated into quality organic fertilizer, but it is necessary to coordinate mechanized treatment of biomass and technology of composting process with microbiological processes for organic matter...

  10. A Development of Rapid, Practical and Selective Process for Preparation of Z-Oximes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bo Ram; Sung, Gi Hyeon; Yoon, Yongjin [Gyeongsang National Univ., Jinju (Korea, Republic of); Kim, Jeumjong [Electronic and Telecommunications Research Institute, Daejeon (Korea, Republic of)

    2013-04-15

    Oximes are important functional groups in organic chemistry due to their synthetic utility as protecting groups for carbonyl groups and their ability to form other functionalities, and their biological activity. Oximes are commonly prepared by condensing aldehydes and ketones with hydroxylamines. These reactions do not always go to completion and reaction times can be long, and therefore there has been interest in more convenient and efficient methods. To avoid the typical disadvantage, conversion of aldehydes and ketones to the corresponding oximes was accomplished by using various catalysts such as organic acid/bases, AcONa, alumina, TiO{sub 2}/SO{sub 4} silica gel, Oxone, NaOH, basic ionic liquid 1-butyl-3-methylimidazolium hydroxide, polyoxometalates, Na{sub 2}SO{sub 4}, and CuSO{sub 4}/K{sub 2}CO{sub 3} under the solvent, the solvent-free or the microwave conditions. These are one and more drowbacks such as long reaction time, use of catalysts, inconvenients due to solid-sate reaction, low yields and limitaion of some carbonyl compounds. On the other hand, H. Sharghi, et al.,14 reported the catalysis of the stereoselectivity of CuSO{sub 4} and K{sub 2}CO{sub 3} in the oximation of aldehydes and ketones under solvent-free conditions. Although this method show high selectivity, it is inconvenient for the large scale experiments and the industrial process due to the solvent-free condition. Therefore, we attempted to develop a more convenient and efficient solution method. According to the literatures, treatment of potassium carbonate with methanol generates slightly the potassium methoxide, which may be useful for forming the free NH{sub 2}OH from its salts. We describe the oximation of aldehyde and ketone using NH{sub 2}OH·HCl/K{sub 2}CO{sub 3} in methanol solvent. We selected oximation of acetophenone (1a) with hydroxylamine hydrochloride as a model and its behavior was investigated in seven solvents involving methanol (Table 1). As shown in the Entry 2 in

  11. Model of temperature field for the preparation process of melt-spun NdFeB powders

    Institute of Scientific and Technical Information of China (English)

    赖彬; 李岩峰; 王会杰; 李安华; 朱明刚; 李卫; 张跃

    2014-01-01

    Melt-spun ribbons which are the important raw material for hot-deformed magnets can be prepared by single-roller melt-spinning. In order to prepare well-structured ribbons, the model of temperature field for single-roller melt-spinning process was constructed in this work. The heat conduction in this process was simplified as one dimensional heat conduction problem. It was shown by modeling that, the temperature field in the melt-spinning before solidification in this model could be described as this equa-tionT(x,t)=Tmoexp[-k(x-x0)-k2αt]+T0. The temperatureT(x,t) of the alloy melts decreased with increased positionx and cooling timet exponentially from the wheel-free surface to the wheel-side surface. The constantk determined the decrease speed of alloy tempera-tureT(x,t), which was proportional to the interfacial heat transfer coefficienth and the interfacial area of heat conductionA0, but in-versely proportional to the thermal conductivityK.x0 was the thickness of the alloy melt. With increasedx0, the temperature differ-ence between wheel-free surface and the wheel-side surface became larger, which would lead to larger difference in grain size. In ex-periments, the influence of melt-spinning process parameters on the temperature field model was discussed, such as cooling roller materials, wheel speed, and so on. Melt-spun ribbons prepared by single-roller melt spinning at different wheel speed were investi-gated and magnetic properties of die-upset magnets from melt-spun ribbons on different cooling roller were analyzed. The variation of grain size in the depth direction consisted with temperature field model. This model provided directions for the preparation of melt-spun ribbons with uniformly distributed fine grains, which were very necessary for producing hot-deformed magnets with high magnetic performance.

  12. Controlling the Color of Lead-Free Red Overglaze Enamels and a Process for Preparing High-Quality Red Paints.

    Science.gov (United States)

    Hashimoto, Hideki; Inada, Hirofumi; Okazaki, Yuki; Takaishi, Taigo; Fujii, Tatsuo; Takada, Jun

    2016-05-04

    Akae porcelain, an artistic Japanese traditional overglaze ceramic typically known for Kakiemon-style ware, has fascinated porcelain lovers around the world for over 400 years because of the graceful red color displayed by akae that matches so well with white porcelain bodies. In this work, we clarified the factors that control the color of akae and those that are conventionally controlled by artisans based on empirical experience. Inspired by a recent particle-design method, we also developed a practical facile process to prepare red paints that yields high-quality akae. Various akae samples were prepared from a combination of lead-free alkali borosilicate glass frits with different particle sizes and hematite powders with differing dispersibilities. Polarized light microscopy, scanning electron microscopy, and transmission electron microscopy analyses indicate that considering only the dispersibility of hematite powders is not sufficient, but the frit-particle size must be controlled to obtain high-quality akae with a high reflectance value for ≥580 nm visible light. In addition, we developed a process for preparing high-quality red paints that uses a large-particle frit powder and a strongly aggregated-hematite powder, both of which are easily obtainable. The red paint composed of frit, hematite, and the solvent is mixed until the paint is drying. By adding more solvent and repeating this process three times, we obtained high-quality akae with a higher reflectance value than for the akae prepared from a frit with submicron-sized particles and weakly aggregated-hematite powder. On the basis of transmission electron microscopic observations, we consider the red paint to consist of a core/shell-like composite structure of frit and hematite, forming a three-dimensional network in the akae glass layer. The good dispersibility of these particles leads to high-quality akae.

  13. Electrochemical properties of CuO hollow nanopowders prepared from formless Cu–C composite via nanoscale Kirkendall diffusion process

    Energy Technology Data Exchange (ETDEWEB)

    Won, Jong Min [Department of Materials Science and Engineering, Korea University, Anam-Dong, Seongbuk-Gu, Seoul 136-713 (Korea, Republic of); Kim, Jong Hwa [Daegu Center, Korea Basic Science Institute, 80 Daehakro Bukgu, Daegu 702-701 (Korea, Republic of); Choi, Yun Ju [Suncheon Center, Korea Basic Science Institute, Suncheon 540-742 (Korea, Republic of); Cho, Jung Sang [Department of Materials Science and Engineering, Korea University, Anam-Dong, Seongbuk-Gu, Seoul 136-713 (Korea, Republic of); Kang, Yun Chan, E-mail: yckang@korea.ac.kr [Department of Materials Science and Engineering, Korea University, Anam-Dong, Seongbuk-Gu, Seoul 136-713 (Korea, Republic of)

    2016-06-25

    Hollow CuO nanopowders are prepared using a simple spray drying process that relied on nanoscale Kirkendall diffusion; these nanopowders have potential applications in lithium-ion batteries. Citric acid is used as both the carbon source material and chelating agent and plays a key role in the preparation of the hollow nanopowders. The formless Cu–C composite that formed as an intermediate product transforms into slightly aggregated CuO hollow nanopowders after post-treatment at 300 and 400 °C under an air atmosphere. The CuO hollow nanopowders exhibit higher initial discharge capacities and better cycling performances than those of the filled-structured CuO nanopowders, which are prepared at a post-treatment temperature of 500 °C under an air atmosphere. The discharge capacities of the CuO nanopowders post-treated at 300, 400, and 500 °C for the 150{sup th} cycle at a current density of 1 A g{sup −1} are 793, 632, and 464 mA h g{sup −1}, respectively, and their capacity retentions calculated from the maximum discharge capacities are 88, 80, and 73%, respectively. The CuO nanopowders with hollow structures exhibit better structural stability for repeated lithium insertion and desertion processes than those with filled structures. - Highlights: • Hollow CuO nanopowders are prepared using a simple spray drying process. • Cu–C composite transforms into CuO hollow nanopowders by Kirkendall diffusion. • Hollow CuO nanopowders show good electrochemical properties for lithium-ion storage.

  14. A solid-phase microextraction fiber with carbon nanoparticles as sorbent material prepared by a simple flame-based preparation process.

    Science.gov (United States)

    Sun, Min; Feng, Juanjuan; Qiu, Huamin; Fan, Lulu; Li, Leilei; Luo, Chuannan

    2013-07-26

    A novel carbon nanoparticles-coated solid-phase microextraction (SPME) fiber was prepared via a simple and low-cost flame-based preparation process, with stainless steel wire as support. Surface characteristic of the fiber was studied with scanning electron microscope. A nano-scaled brushy structure was observed. Coupled to gas chromatography (GC), the fiber was used to extract phthalate esters (PAEs) and polycyclic aromatic hydrocarbons (PAHs) in aqueous samples. Analytical performances of the proposed method were investigated under the optimum extraction conditions (extraction temperature, 40°C; content of KCl, 30% (w/v); extraction time, 50min for PAEs and 40min for PAHs) and compared with other reports for the same analytes. Calibration ranges were 0.06-500μgL(-1) for di-n-butyl phthalate (DBP), and 0.1-300μgL(-1) for di-cyclohexyl phthalate (DCHP) and di-(2-ethyl-hexyl) phthalate (DEHP). For the eight PAHs, good linearity was obtained ranging from 0.01 to 150μgL(-1). Limits of detection were 0.005μgL(-1) for three PAEs and 0.001-0.003μgL(-1) for eight PAHs. The fiber exhibited excellent stability. It can be used for 100 times with RSDs of extraction efficiency less than 22.4%. The as-established SPME-GC method was applied to determine PAEs in food-wrap and PAHs in cigarette ash and snow water, and satisfactory results were obtained. The carbon nanoparticles-coated SPME fiber was efficient for sampling of organic compounds from aqueous samples.

  15. Cell dynamics in the pulpal healing process following cavity preparation in rat molars.

    Science.gov (United States)

    Harada, Masahiro; Kenmotsu, Shin-Ichi; Nakasone, Naohiro; Nakakura-Ohshima, Kuniko; Ohshima, Hayato

    2008-10-01

    Odontoblast-lineage cells acquire heat-shock protein (HSP)-25-immunoreactivity (IR) after they complete their cell division, suggesting that this protein acts as a switch between cell proliferation and differentiation during tooth development. However, there are few available data concerning the relationship between cell proliferation and differentiation following cavity preparation. The present study aims to clarify the expression of HSP-25 in the odontoblast-lineage cells with their proliferative activity after cavity preparation by immunocytochemistry for HSP-25 and cell proliferation assay using 5-bromo-2'-deoxyuridine (BrdU) labeling. In untreated control teeth, intense HSP-25-IR was found in odontoblasts and some subodontoblastic mesenchymal cells. Cavity preparation caused the destruction of odontoblasts and the disappearance of HSP-25-IR was conspicuous at the affected site, although some cells retained HSP-25-IR and subsequently most of them disappeared from the pulp-dentin border by postoperative day 1. Contrary, some subodontoblastic mesenchymal cells with weak HSP-25-IR began to take the place of degenerated cells, although no proliferative activity was recognizable in the dental pulp. Interestingly, proliferative cells in the dental pulp significantly increased in number on day 2 when the newly differentiating cells already arranged along the pulp-dentin border, and continued their proliferative activity in the wide range of the pulp tissue until day 5. These findings indicate that progenitor cells equipped in the subodontoblastic layer firstly migrate and differentiate into new odontoblast-like cells to compensate for the loss of the odontoblast layer, and subsequently the reorganization of dental pulp was completed by active proliferation of the mesenchymal cells occurring in a wide range of pulp tissue.

  16. Synthesis and Properties of ZnO/Al Thin Films Prepared by Dip-Coating Process

    OpenAIRE

    Juhņeviča, I; Mašonkina, M; Mežinskis, G; Gabrene, A

    2015-01-01

    In this work sol–gel dip-coating technique was used to synthesize ZnO and ZnO/Al films. The influence of annealing regime and dopant concentration on the structural properties of ZnO and aluminum doped ZnO (ZnO/Al) films was investigated. The surface morphology and crystallinity of ZnO films were determined using atomic force microscopy and Xray diffraction, respectively. The experimental results show that ZnO and ZnO/Al films prepared using “shock” conditions have smo...

  17. Preparation of Silver Nanoshells on Silica Particles by a Simple Two-step Process

    Institute of Scientific and Technical Information of China (English)

    Yu ZHANG; Ming MA; Ning GU; Ling XU; Kun Ji CHEN

    2004-01-01

    A simple two-step method was developed to prepare silver nanoshells coated on silica paticles.The method involves two steps: concentration of reaction precursor (AgNO3) on particle surfaces and subsequent reduction by formaldehyde.The obtained composite particles were characterized by TEM, ED, and SEM-EDS measurements.The results show that the silver nanoshell is coated on silica particle surface in the form of a polycrystalline (cubic structure) layer with average thickness of 20 nm and weight percentage of 19%.

  18. Low temperature preparation of nanocrystalline solid solution of strontium barium niobate by chemical process

    Indian Academy of Sciences (India)

    Asit B Panda; Amita Pathak; Panchanan Pramanik

    2002-11-01

    SrBa1–Nb2O6 (with = 0.4, 0.5 and 0.6) powders have been prepared by thermolysis of aqueous precursor solutions consisting of triethanolamine (TEA), niobium tartarate and, EDTA complexes of strontium and barium ions. Complete evaporation of the precursor solution by heating at ∼ 200°C, yields in a fluffy, mesoporous carbon rich precursor material, which on calcination at 750°C/2 h has resulted in the pure SBN powders. The crystallite and average particle sizes are found to be around 15 nm and 20 nm, respectively.

  19. Preparation of Poly (ethylene oxide) (PEO) Modified Tungsten Oxide Hybrid Films via Sol-Gel Processing

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Poly (ethylene axide) (PEO) modified WO3 thin films were prepared on glass substrates with special temperature.The sol-gel transition proess was investigated by using DTA-TG,SEM and XRD.The electrochemical characteristic of the films was studied by cyclic voltmmetry measurement.The results show that PEO has heavy effects on the crystallization of WO3 during structure evolution because of the interaction between PEO and WO3.It increases the crystallization temperature of the gels and thus improves the electrochemical properties and cyclic life of WO3 film as electrochromic materials.

  20. Preparation and characterization of gadolinium hydroxide single-crystalline nanorods by a hydrothermal process

    Institute of Scientific and Technical Information of China (English)

    Yi Dong Yin; Guang Yan Hong; Bai Fu Xin

    2007-01-01

    The Gd(OH)3 nanorods with diameters of ca. 40-60 nm and lengths of more than 400-550 nm have been prepared by a novel hydrothermal technique. The structural features and chemical composition of the nanorods were investigated by X-ray diffraction(XRD), transmission electron microscopy (TEM), and field emission scanning electron microscope (FESEM), selected area electron diffraction (SAED), and high resolution transmission electron microscopy (HRTEM). The possible mechanism for the formation of Gd(OH)3 nanorods was proposed.

  1. A new process for preparing dialdehyde by catalytic oxidation of cyclic olefins with aqueous hydrogen peroxide

    Institute of Scientific and Technical Information of China (English)

    YU, Hong-Kun; PANG, Zhen; HUANG, Zu-En; CAI, Rui-Fang

    2000-01-01

    A novel peroxo-nioboplosphate was synthesized for the first time and used as a catalyst in the oxidation reaction of cyclic olefins with aqueous hydrogen peroxide to prepare dialdehydes. The catalyst was characterized by elemental analysis,thermographic analyses, IR, UV/vis, 31P NMR and XPS ~ as [ π-C5H5N(CH2)i3CH3 ]2 [Nb406 (O2)2 (PO4)2] ·6H20 (PTNP). It showed high selectivity to glutaraldehyde in the catalytic oxidation of cyclopentene with aqueous hydrogen peroxide in ethanol.

  2. Hybrid Materials Prepared from Polymers and Self-assembled Systems by Physical Processes

    Institute of Scientific and Technical Information of China (English)

    Jean-Michel; Guenet

    2007-01-01

    1 Results A new type of hybrid materails prepared from ternary systems polymer/bicopper organic complex/solvent is presented.Each binary system displays differing types of behaviour: The polymer solutions produce thermoreversible gels while the bicopper organic complex (designated as CuS8) forms randomly-dispersed,self-assembling threads in organic solvents (See Fig.1(a),(b)).Fig.1 The CuS8 and ips thermoreversible gels Thermoreversible gels possess a fibrillar morphology with a typical mesh size ra...

  3. Biomolecular hybrid material and process for preparing same and uses for same

    Science.gov (United States)

    Kim, Jungbae [Richland, WA

    2010-11-23

    Disclosed is a composition and method for fabricating novel hybrid materials comprised of, e.g., carbon nanotubes (CNTs) and crosslinked enzyme clusters (CECs). In one method, enzyme-CNT hybrids are prepared by precipitation of enzymes which are subsequently crosslinked, yielding crosslinked enzyme clusters (CECs) on the surface of the CNTs. The CEC-enzyme-CNT hybrids exhibit high activity per unit area or mass as well as improved enzyme stability and longevity over hybrid materials known in the art. The CECs in the disclosed materials permit multilayer biocatalytic coatings to be applied to surfaces providing hybrid materials suitable for use in, e.g., biocatalytic applications and devices as described herein.

  4. STUDY ON Ni-Cr SYSTEM SOLAR SELECTIVE THIN FILMS PREPARED BY MAGNETRON REACTIVE SPUTTERING PROCESS

    Institute of Scientific and Technical Information of China (English)

    B.W. Wang; H. Shen

    2002-01-01

    Ni-Cr System solar selective thin solid films were prepared by d.c. magnetron reactivesputtering under the atmosphere of O2 and N2. Ni-Cr alloy was chosen as targetmaterial and copper sheets as substrate. Using SEM, Spectrophotometer and Talystepto analyze the relations between the selective characteristic and the structure, theformation and the thickness of the thin films. The aim is to obtain good solar selectivethin films with high absorptance and low emittance, which is applied to flat plate solarheat collectors.

  5. Reproducible Preparation of Silver Sols with Small Particle Size Using Borohydride Reduction: For Use as Nuclei for Preparation of Larger Particles.

    Science.gov (United States)

    Shirtcliffe; Nickel; Schneider

    1999-03-01

    Silver colloids are useful as substrates for surface enhanced Raman spectroscopy (SERS). The results are, however, seldom quantitative as the distribution of particle sizes in silver suspensions can vary from sample to sample and thus the SERS spectra can vary in intensity. Monodisperse silver sols are relatively difficult to prepare compared with gold or latex colloids as the nucleation process is difficult to control. Previous workers have used a system where small particles are formed in one process and grown in a second reaction. In this paper a simple procedure is outlined by which the small, "seed" particles (starter sols) can be prepared; this method is simpler and more reproducible than that used in the past. The process by which the sols can be grown is not discussed in detail here as it is the subject of a forthcoming publication. Copyright 1999 Academic Press.

  6. Microencapsulation by solvent extraction/evaporation: reviewing the state of the art of microsphere preparation process technology.

    Science.gov (United States)

    Freitas, Sergio; Merkle, Hans P; Gander, Bruno

    2005-02-02

    The therapeutic benefit of microencapsulated drugs and vaccines brought forth the need to prepare such particles in larger quantities and in sufficient quality suitable for clinical trials and commercialisation. Very commonly, microencapsulation processes are based on the principle of so-called "solvent extraction/evaporation". While initial lab-scale experiments are frequently performed in simple beaker/stirrer setups, clinical trials and market introduction require more sophisticated technologies, allowing for economic, robust, well-controllable and aseptic production of microspheres. To this aim, various technologies have been examined for microsphere preparation, among them are static mixing, extrusion through needles, membranes and microfabricated microchannel devices, dripping using electrostatic forces and ultrasonic jet excitation. This article reviews the current state of the art in solvent extraction/evaporation-based microencapsulation technologies. Its focus is on process-related aspects, as described in the scientific and patent literature. Our findings will be outlined according to the four major substeps of microsphere preparation by solvent extraction/evaporation, namely, (i) incorporation of the bioactive compound, (ii) formation of the microdroplets, (iii) solvent removal and (iv) harvesting and drying the particles. Both, well-established and more advanced technologies will be reviewed.

  7. Converting round tendons to flat tendon constructs: Does the preparation process have an influence on the structural properties?

    Science.gov (United States)

    Domnick, C; Herbort, M; Raschke, M J; Schliemann, B; Siebold, R; Śmigielski, R; Fink, C

    2017-05-01

    The structural properties of hamstring tendon grafts were evaluated in a porcine model, after processing it to a flat shape, to better replace or augment anatomic flat structures (e.g. ACL, MPFL or MCL). In this biomechanical study, porcine flexor tendons were used which have a comparable shape to semitendinosus and gracilis tendons. One part of the tendon was prepared to a flat tendon construct by splitting the tendon longitudinally with a knife to half of the diameter of the tendon. The semi-split tendon was scratched out to a flat shape. The other matched part was tested in its original round shape. The tendons (n = 40) have been fixed in a uniaxial testing machine (Zwick/Roell) by cryo-clamps after preparing the fixed ends by 2-0 polyester sutures (2-0 Ethibond(®) EXCEL, Ethicon, Somerville, NJ). In every specimen, there was a free 60-mm tendon part between both clamps. The tendons have been loaded to failure to evaluate typical biomechanical parameters such as stiffness, yield load and maximum load. No statistically significant differences (n.s.) regarding stiffness, yield load and maximum load between natively round and processed flat tendons could be detected. A prepared flat-shaped tendon does not show any different structural properties compared with an original round tendon. Therefore, a flat tendon seems to be a biomechanical stable graft option for anatomic reconstruction or augmentation of injured natively flat-shaped structures such as MCL, MPFL or ACL.

  8. Preparation of cotton linter nanowhiskers by high-pressure homogenization process and its application in thermoplastic starch

    Science.gov (United States)

    Savadekar, N. R.; Karande, V. S.; Vigneshwaran, N.; Kadam, P. G.; Mhaske, S. T.

    2015-03-01

    The present work deals with the preparation of cotton linter nanowhiskers (CLNW) by acid hydrolysis and subsequent processing in a high-pressure homogenizer. Prepared CLNW were then used as a reinforcing material in thermoplastic starch (TPS), with an aim to improve its performance properties. Concentration of CLNW was varied as 0, 1, 2, 3, 4 and 5 wt% in TPS. TPS/CLNW nanocomposite films were prepared by solution-casting process. The nanocomposite films were characterized by tensile, differential scanning calorimetry, scanning electron microscopy (SEM), water vapor permeability (WVP), oxygen permeability (OP), X-ray diffraction and light transmittance properties. 3 wt% CLNW-loaded TPS nanocomposite films demonstrated 88 % improvement in the tensile strength as compared to the pristine TPS polymer film; whereas, WVP and OP decreased by 90 and 92 %, respectively, which is highly appreciable compared to the quantity of CLNW added. DSC thermograms of nanocomposite films did not show any significant effect on melting temperature as compared to the pristine TPS. Light transmittance ( T r) value of TPS decreased with increased content of CLNW. Better interaction between CLNW and TPS, caused due to the hydrophilic nature of both the materials, and uniform distribution of CLNW in TPS were the prime reason for the improvement in properties observed at 3 wt% loading of CLNW in TPS. However, CLNW was seen to have formed agglomerates at higher concentration as determined from SEM analysis. These nanocomposite films can have potential use in food and pharmaceutical packaging applications.

  9. Effect of ammonium hydroxide on preparation process of YBa2Cu3O7-x superconductor by sol gel method

    Directory of Open Access Journals (Sweden)

    H Arabi

    2006-09-01

    Full Text Available  In this paper the effect of ammonium hydroxide addition to the solution of metallic oxide on sol gel preparation process of YBCO is studied with differential thermal analysis, thermal graviometry and X-ray diffraction. Two samples with and without ammonium hydroxide. Ammonium hydroxide prevents both barium nitrate precipitate during the gel preparation and also unwanted reaction as well as increasing homogeneous product. After drying the gel, the samples heated up to 1050°C in DTA apparatus in order to find more accurate the type and the temperature of reaction during the preparation process. After the initial reactions in the samples, Y2Cu2O5 and 123 phases are created in the range of 780-840°C and then the 123 phase is strengthened at 900-950°C. As shown in X-ray data, 123 was the only phase after this range. In addition ammonium hydroxide support and increase the creation of 123 phase at lower temperature.

  10. Preparation and use of endotoxin indicators for depyrogenation process studies. LAL Users Group.

    Science.gov (United States)

    1989-01-01

    Biological Indicators (B.I.'s) have traditionally been employed in the validation and routine monitoring of sterilization processes used for the manufacture and control of pharmaceuticals and medical devices. In this paper, the phrase "Endotoxin Indicator" has been coined to describe a tool analogous to the BI which can be used in the validation and routine control of endotoxin reduction processes. Like the BI, the Endotoxin Indicator provides the user with an in vitro biological test to complement physical measurement used to control the manufacturing process. It must be remembered that the total pyroburden in an aseptically processed drug is the sum of the pyroburden of each factor contributing to the manufacture of that product. This includes raw materials, packaging components, the environment and the manufacturing process itself. Therefore, all aspects of the process must be considered for a complete validation. This pyroburden may also change during processing of a drug. Fluctuations in pH, solvent content, and temperature may decrease pyroburden while introduction of some raw materials, especially water, may increase endotoxin content. Regularly scheduled monitoring of all aseptic processes should identify and address each step of the process considered to have potential for the possible introduction or removal of endotoxin in the final product. Most of these situations can be thoroughly studied using Endotoxin Indicators to challenge routine production conditions, thereby providing insight to the assurance of endotoxin-free final products.

  11. An Environmentally Friendly Process for the Preparation of UHMWPE As-Spun Fibres

    Directory of Open Access Journals (Sweden)

    Abdul Waqar Rajput

    2014-01-01

    Full Text Available The extrusion of ultra high molecular weight polyethylene (UHMWPE fibres cannot be achieved by conventional extrusion processes due to its very high melt viscosity. To overcome this limitation, UHMWPE is first dissolved in a petrochemical to form a gel before extrusion. The petrochemicals used to dissolve the polymer then need to be removed using other chemicals making the process unfriendly to the environment. This article is focused on finding an environmentally friendly, natural solution to replace these chemicals and altering the process to potentially reduce the process cost.

  12. The Optimization of Matrix Preparation Process and Performance Testing for Molten Carbonate Fuel Cell

    Directory of Open Access Journals (Sweden)

    Jian Cheng

    2014-01-01

    Full Text Available A key component in the molten carbonate fuel cell (MCFC is electrolyte matrix, which provides both ionic conduction and gas sealing. The aim of this work is to investigate the effects of selected operating conditions on the performance of the matrix preparation. Slurries were prepared to produce matrices by the technique of tape casting. The characteristics of the slurries and matrices were examined by laser particle size analyzer, scanning electron microscopy, and BET surface area analyzer. The testing results revealed that a slurry composition with 40 wt.% lithium aluminate was the optimal formulation to produce a good matrix with a pore size distribution of 0.1–0.4 μm and porosity of 50 vol.%. Coarse and fine LiAlO2 particles were added in the matrix slurry to enhance the mechanical strength. Several green sheets were heated and pressed to enhance the bulk density to get a dense matrix of MCFC. Finally, a single MCFC was assembled and tested. The testing results showed the matrix with 40% solid loading gave the maximum discharge current of 20 A at 0.56 V.

  13. Preparation of a crosslinked bioimprinted lipase for enrichment of polyunsaturated fatty acids from fish processing waste.

    Science.gov (United States)

    Yan, Jinyong; Li, Lifan; Tang, Qianli; Jiang, Manzhou; Jiang, Shenzhou

    2010-10-01

    Geotrichum sp. lipase modified with a combined method composed of crosslinking and bioimprinting was employed to selectively hydrolyze waste fish oil for enrichment of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in glycerides. Crosslinked polymerization by monomer (polyethylene glycol 400 dimethyl acrylate), crosslinker (trimethylolpropane trimethylacrylate), and photoinitiator (benzoin methyl ether) coupled to bioimprinting using palmitic acid as imprint molecule, resulted in much more effective enzyme preparation used in aqueous hydrolysis reaction. Since the crosslinked polymerization modification maintained bioimprinted property and gave good dispersion of enzyme in reaction mixture, the crosslinked bioimprinted enzyme exhibited higher hydrolysis temperature, enhanced specific activity, shorter hydrolysis time, and better operational stability compared to free lipase. Crude fish oil was treated at 45 degrees C with this crosslinked bioimprinted lipase for 8 h, and 46% hydrolysis degree resulted in the production of glycerides containing 41% of EPA and DHA (EPA+DHA), achieving 85.7% recovery of initial EPA and DHA. The results suggested that bioimprinted enzymes did not lose their induced property in aqueous environment when prepared according to the described crosslinking-bioimprinting method. It could also be seen that the crosslinked bioimprinted lipase was effective in producing glycerides that contained a higher concentration of polyunsaturated fatty acid with better yield.

  14. Activity Enhancement of Vanadium Catalysts with Ultrasonic Preparation Process for the Oxidation of Sulfur Dioxide

    Institute of Scientific and Technical Information of China (English)

    Zhenxing Chen; Honggui Li; Lingsen Wang

    2003-01-01

    The effect of ultrasonic cavitations on the activity of vanadium catalysts at low temperatures for the oxidation of sulfur dioxide, in which refined carbonized mother liquor had been added, was investigated.Twenty minutes were needed to produce obvious cavitations when the catalyst raw material was treated in the 50 W ultrasonic generator. However, only 10 minutes would be needed in a 150 W ultrasonic generator.The higher the temperature of the wet material, the less time was needed to produce cavitations, and the optimal temperature was 60 ℃. The water content in the wet material mainly affected the quantity of cavitations. Ls-8 catalyst was prepared using ultrasonic. Its activity for conversion of SO2 reached to 52.5% at 410 ℃ and 4.2% at 350 ℃. The differential thermal analyses indicate that both endothermic peaks and exothermic peaks noticeably shifted forward compared with Ls catalyst prepared without ultrasonic, and SEM results show a uniform pore size distribution for Ls-8 catalyst.

  15. The preparation process and feature of the topological insulator Bi2Te3

    Institute of Scientific and Technical Information of China (English)

    Peng Chen; Dajin Zhou; Pingyuan Li; Yajing Cui; Yongliang Chen

    2014-01-01

    Topological insulators are insulating in the bulk but have metallic surface states. Its unique physicochemi-cal properties can find numerous applications in electron-ics, spintronics, photonics, the energy sciences, and the signal control of transportation. We report an experimental approach to synthesize the high-quality single crystal of topological insulator Bi2Te3 by using self-flux method. We obtained the optimal preparation conditions by adjusting the parameters of heat treatment, and successfully prepared the single-crystal Bi2Te3 sample. The as-grown samples have a surface with bright metallic luster and are soft and fragile. Furthermore, Bi2Te3 has the obvious layer structure from SEM results. The data of X-ray diffraction and scanning electron microscope show that Bi2Te3 single crystal grows along the c-axis with the order of Te(1)-Bi-Te(2)-Bi-Te(1) and crystallizes in the hexagonal system with space group of R/3 m. The q-T curve shows that q decreases with temperature, showing metallic behavior over the whole temperature range.

  16. Oromucosal film preparations: points to consider for patient centricity and manufacturing processes.

    Science.gov (United States)

    Krampe, Raphael; Visser, J Carolina; Frijlink, Henderik W; Breitkreutz, Jörg; Woerdenbag, Herman J; Preis, Maren

    2016-01-01

    According to the European Pharmacopoeia, oromucosal films comprise mucoadhesive buccal films and orodispersible films. Both oral dosage forms receive considerable interest in the recent years as commercially available pharmaceutical products and as small scale personalized extemporaneous preparations. In this review, technological issues such as viscosity of the casting liquid, mechanical properties of the film, upscaling and the stability of the casting solution and produced films will be discussed. Furthermore, patient-related problems like appearance, mucosal irritation, taste, drug load, safety and biopharmaceutics are described. Current knowledge and directions for solutions are summarized. The viscosity of the casting solution is a key factor for producing suitable films. This parameter is amongst others dependent on the polymer and active pharmaceutical ingredient, and the further excipients that are used. For optimal patient compliance, an acceptable taste and palatability are desirable. Safe and inert excipients should be used and appropriate packaging should be provided to produced films. Absorption through the oral mucosa will vary for each active compound, formulation and patient, which gives rise to pharmacokinetic questions. Finally, the European Pharmacopoeia needs to specify methods, requirement and definitions for oromucosal film preparations based on bio-relevant data.

  17. Effect of preparation processes and structural insight into the supermolecular system: Bisacodyl and β-cyclodextrin inclusion complex

    Energy Technology Data Exchange (ETDEWEB)

    Li, Shanshan [College of Chemical Engineering, Sichuan University, Chengdu 610065 (China); Zhai, Yuanming [Analytical and Testing Center, Sichuan University, Chengdu 610064 (China); Yan, Jin; Wang, Lili; Xu, Kailin [College of Chemical Engineering, Sichuan University, Chengdu 610065 (China); Li, Hui, E-mail: lihuilab@sina.com [College of Chemical Engineering, Sichuan University, Chengdu 610065 (China)

    2016-01-01

    In this study, β-cyclodextrin (β-CD) and bisacodyl were chosen as model host and guest molecule to explore the effect of preparation processes on the physicochemical properties of inclusion complexes (ICs) and to gain an insight into the structure of ICs. The influence of temperature and pH on complexation was studied by multiple temperature–pH phase solubility analysis. The most favorable conformation was predicted by molecular modeling using AutoDock. {sup 1}H nuclear magnetic resonance and rotating frame nuclear Overhauser effect spectroscopy further confirmed the structure. Moreover, bisacodyl·β-CD ICs in solid state were successfully prepared via three different procedures (co-crystallization, co-evaporation, and co-grinding) and fully characterized by several solid-state techniques, namely, Fourier transform infrared spectroscopy, X-ray powder diffraction, thermogravimetric analysis, differential scanning calorimetry, solid-state NMR spectroscopy, and scanning electron microscopy. It was found that acid solution and low temperature were unfavorable for formation of bisacodyl·β-CD. The pyridine moiety was suggested to be enclosed in the hydrophobic cavity of β-CD. The complexes prepared using co-crystallization showed properties similar to those prepared using co-evaporation. Moreover, ICs obtained by co-evaporation and co-grinding had higher loading efficiency, water solubility, and dissolution rate than ICs obtained by co-crystallization. - Highlights: • The structure of inclusion complex-bisacodyl·β-CD was determined. • Thermodynamic behaviors of complexation under different conditions were discussed. • Products from three different preparation methods were systemically compared. • Co-crystallization and co-evaporation produced similar complexes. • Co-evaporation and co-grinding had better effects than co-crystallization.

  18. Preparation and properties of aqueous castor oil-based polyurethane-silica nanocomposite dispersions through a sol-gel process.

    Science.gov (United States)

    Xia, Ying; Larock, Richard C

    2011-09-01

    Waterborne castor oil-based polyurethane-silica nanocomposites with the polymer matrix and silica nanoparticles chemically bonded have been successfully prepared through a sol-gel process. The formation of silica nanoparticles in water not only reinforces the resulting coatings, but also increases the crosslink density of the nanocomposites. The (29)Si solid state NMR spectrum indicates the formation of silica and the TEM indicates that the nanoparticles are embedded in the polymers, resembling a core-shell structure. The silica nanoparticles in the polymer matrix play an important role in improving both the mechanical properties and the thermal stabilities of the resulting nanocomposites. This work provides an effective and promising way to prepare biorenewable, high performance nanocomposite coatings.

  19. Effects of Heating Processing on Microstructure and Magnetic Properties of Mn-Zn Ferrites Prepared via Chemical Co-precipitation

    Institute of Scientific and Technical Information of China (English)

    CHEN Shijie; XIA Jingbing; DAI Jianqing

    2015-01-01

    The fine powders of Mn-Zn ferrites with uniform size were prepared via chemical co-precipitation method. X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), frequency dependence of permeability and metallographical microscope were used to investigate the crystal structure, surface topography and magnetic properties of the powders and the sintering samples. The experimental results demonstrate that the precursor powders have formed a pure phase cubic spinel MnxZn1-xFe2O4 while in the reactor and show deifnite magnetism, which can solve the dififcult issue in washing process effectively. When calcined beneath 450℃, the powders have intact crystal form and the crystallite size is less than 20 nm. Comparison tests of sintering temperatures show that 1 300℃ is the ideal sintering temperature for Mn-Zn ferrites prepared by using the chemical co-precipitation.

  20. Preparation and luminescence properties of La6MoO12:Eu3+/PVA nanofibers by Pechini/electrospinning process.

    Science.gov (United States)

    Qin, Chuanxiang; Gu, Mingbo; Huang, Yanlin; Dai, Lixing; Chen, Guoqiang; Shi, Liang; Qiao, Xuebin; Seo, Hyo Jin

    2011-11-01

    The 20% concentration Eu3+-based red-emitting phosphor, nano-sized La6MoO12:Eu3+ was prepared by the Pechini method. X-ray diffraction (XRD), thermogravimetric and differential thermal analysis (TG-DTA), scanning electron microscopy (SEM), photoluminescence (PL), and decay curves were used to characterize the resulting samples. The phosphor can be efficiently excited by near UV light and exhibits an intense red luminescence corresponding to the electric dipole transition 5D0 --> 7F2 at 615 nm. When the phosphor was mixed into poly(vinyl alcohol) aqueous solution, the fluorescent nanofibers could be prepared by electrospinning process. It was suggested that the La6MoO12:Eu3+ phosphor would be a promising red component for solid-state lighting devices based on InGaN or GaN light-emitting diodes.

  1. Preparation of lithium-rich layered oxide micro-spheres using a slurry spray-drying process

    Science.gov (United States)

    Hou, Mengyan; Guo, Shaoshuai; Liu, Jinlong; Yang, Jun; Wang, Yonggang; Wang, Congxiao; Xia, Yongyao

    2015-08-01

    0.5Li2MnO3·0.5LiMn1/3Ni1/3Co1/3O2 microspheres are prepared by a slurry spray-drying process (SD-LLO) with subsequent heat treatment. SEM images show that the SD-LLO microspheres are composed of nano-size primary particles. These particles are quite different from conventional LLO microspheres, which are composed of micron-scale plate-like primary particles prepared by a co-precipitation method (CP-LLO). The SD-LLO material experiences a smaller voltage drop during cycling than CP-LLO when used as cathode material in lithium-ion batteries. High-resolution transmission electron microscopy (HR-TEM) and energy dispersive spectroscopy (EDS) indicate that the smaller voltage drop of SD-LLO can be attributed to a more homogeneous distribution of transition metals.

  2. PROCESSING AND CHARACTERIZATION OF TUBULAR CERAMIC SUPPORT FOR MICROFILTRATION MEMBRANE PREPARED FROM PYROPHYLLITE CLAY

    Directory of Open Access Journals (Sweden)

    Abedallah Talidi

    2011-09-01

    Full Text Available Tubular macroporous support for ceramic microfiltration membranes were prepared by extrusion followed by sintering of the low cost pyrophyllite clay. Clay powders mixed with some organic additives can be extruded to form a porous tubular support. The average pore size of the membrane is observed to increase from 5 µm to 10.8 µm when sintering temperature increase from 900 °C to 1200 °C. However, with the increase in temperature from 900 °C to 1200 °C, the support porosity is reduced from 47% to 30% and flexural strength is increased from 4 MPa to 17 MPa. The fabricated macro-porous supports are expected to have potential applications in the pre-treatment and also can be used like support for membranes of ultra-filtration.

  3. Photocatalytic performance of Cu2O composite octahedra prepared by a propanetriol-reduced process

    Science.gov (United States)

    Zhang, Lihui; Wang, Xiangfu

    2014-12-01

    Cu2O and Ag/Cu2O composite octahedra were synthesized via a hydrothermal reaction of CuAc2 with urea in H2O-propanetriol binary solution by adjusting the quantity of AgNO3 at 180 °C for 10 h. The influence of reaction temperature and time on the morphology and phase of the products was investigated, and a possible growth mechanism of Cu2O octahedron was also proposed. The photocatalytic activities of the as-prepared Cu2O and Ag/Cu2O octahedra for the degradation of methyl orange aqueous solution were studied. The results show that they are effective photocatalysts for the degradation of methyl orange, and the photocatalytic ability of Ag/Cu2O composite is stronger than that of Cu2O octahedra, which are expected to be useful in the treatment of wastewaters.

  4. Preparation of Si3N4 Form Diatomite via a Carbothermal Reduction-Nitridation Process

    Science.gov (United States)

    Ma, Bin; Huang, Zhaohui; Mei, Lefu; Fang, Minghao; Liu, Yangai; Wu, Xiaowen; Hu, Xiaozhi

    2016-05-01

    Si3N4 was produced using diatomite and sucrose as silicon and carbon sources, respectively. The effect of the C/SiO2 molar ratio, heating temperature and soaking time on the morphology and phase compositions of the final products was investigated by scanning electron microscopy, x-ray diffraction analysis and energy dispersive spectroscopy. The phase equilibrium relationships of the system at different heating temperatures were also investigated based on the thermodynamic analysis. The results indicate that the phase compositions depended on the C/SiO2 molar ratio, heating temperature and soaking time. Fabrication of Si3N4 from the precursor via carbothermal reduction nitridation was achieved at 1550°C for 1-8 h using a C/SiO2 molar ratio of 3.0. The as-prepared Si3N4 contained a low amount of Fe3Si (<1 wt.%).

  5. Research of Hydrogen Preparation with Catalytic Steam-Carbon Reaction Driven by Photo-Thermochemistry Process

    Directory of Open Access Journals (Sweden)

    Xiaoqing Zhang

    2013-01-01

    Full Text Available An experiment of hydrogen preparation from steam-carbon reaction catalyzed by K2CO3 was carried out at 700°C, which was driven by the solar reaction system simulated with Xenon lamp. It can be found that the rate of reaction with catalyst is 10 times more than that without catalyst. However, for the catalytic reaction, there is no obvious change for the rate of hydrogen generation with catalyst content range from 10% to 20%. Besides, the conversion efficiency of solar energy to chemical energy is more than 13.1% over that by photovoltaic-electrolysis route. An analysis to the mechanism of catalytic steam-carbon reaction with K2CO3 is given, and an explanation to the nonbalanced [H2]/[CO + 2CO2] is presented, which is a phenomenon usually observed in experiment.

  6. Preparation and characterization of whey protein hydrolysates: applications in industrial whey bioconversion processes.

    Science.gov (United States)

    Perea, A; Ugalde, U; Rodriguez, I; Serra, J L

    1993-05-01

    A whey protein hydrolysate was prepared by incubation of reconstituted whey or a whey protein concentrate with Alcalase 0.6L. The proteolytic degradation of alpha-lactalbumin and beta-lactoglobulin initially resulted in 6-kDa and, later, 2.5-kDa degradation products, quickly followed by the appearance of multiple peptides of 1 kDa or smaller. The hydrolysate showed a steady increase in solubility and a biphasic change in foaming characteristics with decreasing peptide size. At the highest degree of hydrolysis achieved (22%), the majority of the peptides were smaller than 1 kDa and could be efficiently assimilated by the yeast Kluyveromyces marxianus growing in a defined medium.

  7. Electrically Conductive, Optically Transparent Polymer/Carbon Nanotube Composites and Process for Preparation Thereof

    Science.gov (United States)

    Connell, John W. (Inventor); Smith, Joseph G. (Inventor); Harrison, Joycelyn S. (Inventor); Park, Cheol (Inventor); Watson, Kent A. (Inventor); Ounaies, Zoubeida (Inventor)

    2011-01-01

    The present invention is directed to the effective dispersion of carbon nanotubes (CNTs) into polymer matrices. The nanocomposites are prepared using polymer matrices and exhibit a unique combination of properties, most notably, high retention of optical transparency in the visible range (i.e., 400-800 nm), electrical conductivity, and high thermal stability. By appropriate selection of the matrix resin, additional properties such as vacuum ultraviolet radiation resistance, atomic oxygen resistance, high glass transition (T.sub.g) temperatures, and excellent toughness can be attained. The resulting nanocomposites can be used to fabricate or formulate a variety of articles such as coatings on a variety of substrates, films, foams, fibers, threads, adhesives and fiber coated prepreg. The properties of the nanocomposites can be adjusted by selection of the polymer matrix and CNT to fabricate articles that possess high optical transparency and antistatic behavior.

  8. Preparation and thermal stability of nickel nanowires via self-assembly process under magnetic field

    Indian Academy of Sciences (India)

    Hu Wang; Ming Li; Xiaoyu Li; Kenan Xie; Li Liao

    2015-09-01

    Nickel nanowires were synthesized via a template-free method in an aqueous solution system combined with chemical reduction and magnetic field. The suitable concentration of Ni ions and reaction time were controlled in order to obtain nickel wires with uniform sizes. The products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, thermogravimetry and differential scanning calorimetry. The results showed that the Ni nanowires with large aspect ratio up to 200 had uniform size and morphology, about 200 nm. Especially, it is noteworthy that the samples were stable in air when the temperature was lower than 318°C. The study would provide a facile method to prepare nickel nanowires with homogeneous diameter and high thermal stability, which could be used in catalysing CO2 hydrogenation.

  9. High-field magnetization process of granular Co-Cu alloys prepared by melt spinning

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    High solid-solubility Co15Cu35 alloys have been prepared by melt spinning and submitted to isothermal and anisothermal annealing to obtain granular alloys.The X-ray diffraction(XRD) patterns were measured to invesugate the decomposition of supersaturated solid solution induced by annealing.The atomic diffusion and structural evolution during the heat treatment were investigated.In view of the problems limiting their appllcation.the high-field magneazation curves were measured.By a fit to the high-field magnetization curves,the granuiar alloys are found hard to be magnetically saturated at the early stage of nucleation and growth.The magnetization behavior was correlaced to the annealed-induced structureal evolution and also to the magnetoresistance effect.

  10. Prolonged release matrix pellets prepared by melt pelletization. I. Process variables

    DEFF Research Database (Denmark)

    Thomsen, L.J.; Schaefer, T.; Sonnergaard, Jørn

    1993-01-01

    A melt pelletization process was investigated in an 8 litre laboratory scale high shear mixer using a formulation with paracetamol, glyceryl monostearate 40-50, and microcrystalline wax. The effects of jacket temperature, product temperature during massing, product load, massing time and impeller...... speed were investigated by means of factorially designed experiments. The maximum yield of pellets in the range of 500-1400 μm was found to approx. 90%. For process conditions preventing deposition of moist mass, the process was found to be reproducible. Impeller speed and massing time were found...

  11. New Process for Grain Refinement of Aluminum. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Joseph A. Megy

    2000-09-22

    A new method of grain refining aluminum involving in-situ formation of boride nuclei in molten aluminum just prior to casting has been developed in the subject DOE program over the last thirty months by a team consisting of JDC, Inc., Alcoa Technical Center, GRAS, Inc., Touchstone Labs, and GKS Engineering Services. The Manufacturing process to make boron trichloride for grain refining is much simpler than preparing conventional grain refiners, with attendant environmental, capital, and energy savings. The manufacture of boride grain refining nuclei using the fy-Gem process avoids clusters, salt and oxide inclusions that cause quality problems in aluminum today.

  12. Influence of some formulation and process parameters on the stability of lysozyme incorporated in corn flour- or corn starch-based extruded materials prepared by melt blending processing.

    Science.gov (United States)

    Jbilou, Fouzia; Galland, Sophie; Telliez, Camille; Akkari, Zied; Roux, Roselyne; Oulahal, Nadia; Dole, Patrice; Joly, Catherine; Degraeve, Pascal

    2014-12-01

    In order to obtain an antimicrobial biodegradable material, corn flour was extruded with 1% of lysozyme. Since the limited stability of natural preservatives such as lysozyme is a common bottleneck to the elaboration of active biomaterials by melt blending processes, the influence of formulation and of extrusion processing temperature on its residual enzymatic activity was investigated. To assess the contribution of process parameters such as temperature, shear stress and of related formulation parameters such as glycerol and moisture contents, the stability of lysozyme following its extrusion or its thermoforming with plasticized corn starch or thermal treatments in aqueous glycerol solutions was also studied. Increasing glycerol content from 25% to 30% significantly limited inactivation of lysozyme during extrusion, while increasing initial moisture content of the mixture from 14.5% to 28.5% had the opposite effect. These observations open the possibility to prepare active materials retaining more than 60±7% of initial lysozyme activity.

  13. Preparation and physicochemical characterization of matrix pellets containing APIs with different solubility via extrusion process.

    Science.gov (United States)

    Hegyesi, Diána; Thommes, Markus; Kleinebudde, Peter; Sovány, Tamás; Kása, Péter; Kelemen, András; Pintye-Hódi, Klára; Regdon, Géza

    2017-03-01

    In this study, a multiparticulate matrix system was produced, containing two different active pharmaceutical ingredients (APIs): enalapril-maleate and hydrochlorothiazide. The critical control points of the process were investigated by means of factorial design. Beside the generally used microcrystalline cellulose, ethylcellulose was used as matrix former to achieve modified drug release ensured by diffusion. The matrix pellets were made by extrusion-spheronization using a twin-screw extruder. Some pellet properties (aspect ratio, 10% interval fraction, hardness, deformation process) were determined. The aim of our study was to investigate how the two different APIs with different solubility and particle size influence the process. The amount of the granulation liquid plays a key role in the pellet shaping. A higher liquid feed rate is preferred in the pelletization process.

  14. Relationships between phase morphology and deformation mechanisms in polymer nanocomposite nanofibres prepared by an electrospinning process.

    Science.gov (United States)

    Kim, G M; Lach, R; Michler, G H; Pötschke, P; Albrecht, K

    2006-02-28

    Relationships between phase morphology and mechanical deformation processes in various electrospun polymer nanocomposite nanofibres (PNCNFs) containing different types of one-, two- and three-dimensional nanofiller have been investigated by transmission electron microscopy using in situ tensile techniques. From the study of the phase structure of electrospun PNCNFs, two morphological standard types are classified for the analysis of deformation mechanisms: the binary system (polymer matrix and nanofillers), and the ternary system (polymer matrix, nanofillers and nanopores on the fibres surface). According to these categories, deformation processes have been characterized, and different schematic models for these processes are proposed. The finding of importance in the present work is a brittle-to-ductile transition in polymer nanocomposite fibres during in situ tensile deformation processes. This unique feature in the deformation behaviour of electrospun PNCNFs provides an optimal balance of stiffness, strength and toughness for use as reinforcing elements in a polymer based composite of a new kind.

  15. Processing of cassava to produce ethanol - effect of raw material preparation

    Energy Technology Data Exchange (ETDEWEB)

    Greenfield, P.F.; Brooks, R.B.

    1982-06-01

    The effect of disintegration severity on starch hydrolysis and ethanol production from cassava roots and stems has been evaluated. It was found that a considerable fraction of the starch in the roots was made available for hydrolysis with relatively crude processing; all such material was readily fermented. To achieve a very high fermentables yield, either very intensive processing or, preferably, a two stage process, with the second stage being applied only to the oversize material, is required. Whether it is economically viable to process the oversize material further depends on a number of site-specific factors. The two stage option appears the more attractive alternative especially in small to medium size cassava to ethanol plants because of the need to minimise power requirements and thereby steam usage.

  16. Preparation of TiO2 Inverse Opal via a Modified Filling Process

    Institute of Scientific and Technical Information of China (English)

    ZHOU Qian; DONG Peng; YI Gui-Yun; LIU Li-Xia; CHENG Bing-Ying

    2005-01-01

    @@ By applying polystyrene opals made by a vertical deposition method as the templates, a modified filling method and a well-controlled calcination process, we have successfully obtained a large-area ordered TiO2 inverse opal with a higher volume fraction (14.5%) and a visible photonic bandgap. The influences of the filling process and calcination conditions on the fabrication of the TiO2 inverse opal are investigated.

  17. La-Doped CaCu3Ti4O12 Prepared By Conventional And Microwave Processing

    Science.gov (United States)

    Sharif, Nur Shafiza A.; Ahmad, Zainal A.; Hutagalung, Sabar D.

    2010-01-01

    Two processing techniques were used to prepare separate samples of undoped and La-doped CaCu3Ti4O12: the conventional furnace and microwave processing. Stoichiometric composition of undoped CaCu3Ti4O12 was produced by mixing starting materials of Ca(OH)2, CuO and TiO2 powder. The mixed powder was milled and then calcined, compacted and sintered using either a furnace (conventional) or a domestic microwave oven (microwave processing). The La2O3 was added to undoped CaCu3Ti4O12 in order to prepare the La-doped CaCu3Ti4O12 with different doping concentrations. The conventional furnace heating technique requires a calcination temperature of 900° C for 12 hours before the mixture is sintered at 1000° C for 12 hours. However, a single phase CaCu3Ti4O12 compound was successfully synthesized using a microwave oven for a calcination time of 30 minutes. Longer microwave sintering time tends to produce denser CaCu3Ti4O12 pellets.

  18. Preparation and Characterization of LiTaO3 Films Derived by an Improved Sol-Gel Process

    Institute of Scientific and Technical Information of China (English)

    Jun GOU; Jun WANG; Ming YANG; Zehua HUANG; Weizhi LI; Yadong JIANG

    2013-01-01

    In this paper,an improved sol-gel method was suggested to obtain high-concentration LiTaO3 precursor solution for simplified experimental conditions and thicker films,by mixing lithium acetate and tantalum ethoxide in a 1,2-Propylene glycol solution.Compared to traditional methods,the process was done without weak acidic solution and absolute dry experimental condition.Results of a comparative study of LiTaO3 thin films derived by the improved sol-gel process and a traditional process using 2-methoxy ethanol as solvent were presented.Nano-crystalline LiTaO3 films with rhombohedral structures were formed in both methods after annealing at 650 ° for 5 min.The thickness of each LiTaO3 layer coated onto the substrate increased from 25 nm to 110 nm when 2-methoxy ethanol was replaced by 1,2-Propylene glycol.LiTaO3 films with a stronger preferential orientation were obtained in 1,2-Propylene glycol due to its higher boiling point and slower volatilization rate.On the other hand,the diffraction peak intensity of LiTaO3 thin films prepared using 1,2-Propylene glycol was weaker than that of the films prepared using 2-methoxy ethanol due to decreased times of annealing.

  19. Preparation of Li4Ti5O12 electrode thin films by a mist CVD process with aqueous precursor solution

    Directory of Open Access Journals (Sweden)

    Kiyoharu Tadanaga

    2015-03-01

    Full Text Available Spinel Li4Ti5O12 thin films were prepared by a mist CVD process, using an aqueous solution of lithium nitrate and a water-soluble titanium lactate complex as the source of Li and Ti, respectively. In this process, mist particles ultrasonically atomized from a source aqueous solution were transferred by nitrogen gas to a heating substrate to prepare thin films. Scanning electron microscopy observation showed that thin films obtained by this process were dense and smooth, and thin films with a thickness of about 500 nm were obtained. In the X-ray diffraction analysis, formation of Li4Ti5O12 spinel phase was confirmed in the obtained thin film sintered at 700 °C for 4 h. The cell with the thin films as an electrode exhibited a capacity of about 110 mAh g−1, and the cell showed good cycling performance during 10 cycles.

  20. Preparation and Characterization of Malaysian Dolomites as a Tar Cracking Catalyst in Biomass Gasification Process

    Directory of Open Access Journals (Sweden)

    M. A. A. Mohammed

    2013-01-01

    Full Text Available Three types of local Malaysian dolomites were characterized to investigate their suitability for use as tar-cracking catalysts in the biomass gasification process. The dolomites were calcined to examine the effect of the calcination process on dolomite’s catalytic activity and properties. The modifications undergone by dolomites consequent to thermal treatment were investigated using various analytical methods. Thermogravimetric and differential thermal analyses indicated that the dolomites underwent two stages of decomposition during the calcination process. The X-ray diffraction and Fourier-transform infrared spectra analyses showed that thermal treatment of dolomite played a significant role in the disappearance of the CaMg(CO32 phase, producing the MgO-CaO form of dolomite. The scanning electron microscopy microphotographs of dolomite indicated that the morphological properties were profoundly affected by the calcination process, which led to the formation of a highly porous surface with small spherical particles. In addition, the calcination of dolomite led to the elimination of carbon dioxide and increases in the values of the specific surface area and average pore diameter, as indicated by surface area analysis. The results showed that calcined Malaysian dolomites have great potential to be applied as tar-cracking catalysts in the biomass gasification process based on their favorable physical properties.

  1. Preparation and Characterization on Nano-Sized Barium Titanate Powder Doped with Lanthanum by Sol-Gel Process

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The nano-sized BaTiO3:La3+ powders were prepared by sol-gel process using butyl phthalate, barium acetate and lanthanum oxide as raw material, and these samples were tested by means of TG-DTA, XRD and SEM. The results indicate that with the annealing temperature and the doped concentration rising, the powders' particle sizes will increase and decrease respectively. When annealing temperature is 900 ℃ and doped concentration is 7%, the phase is cubic without other phases, and the particle size of power is 43.34 nm.

  2. CaCO{sub 3}/Ca-P biphasic materials prepared by microwave processing of natural aragonite and calcite

    Energy Technology Data Exchange (ETDEWEB)

    Pena, J.; LeGeros, R.Z.; Rohanizadeh, R.; LeGeros, J.P. [New York Univ., NY (United States). Coll. of Dentistry

    2001-07-01

    The purpose of this study was to prepare CaCO{sub 3}/Ca-P biphasic or composite materials using microwave technology. Particles of coral (natural aragonite) and a porous limestone (natural calcite) were suspended in phosphate solutions of different pH and concentrations and heated for different periods (up to 5 hrs) using a domestic microwave. Parallel experiments were carried out using hydrolysis method. Higher extents of transformation were observed with microwave processed materials. Depending on the reaction pH and reaction period, partial transformation of aragonite (coral) or calcite (limestone) to acidic calcium (monetite) or basic (carbonatehydroxyapatite, CHA) calcium phosphates was achieved (orig.)

  3. Ferromagnetism of Mn-doped ZnO nanoparticles prepared by sol-gel process at room temperature

    Institute of Scientific and Technical Information of China (English)

    HUANG Gui-jun; WANG Jin-bin; ZHONG Xiang-li; ZHOU Gong-cheng; YAN Hai-long

    2006-01-01

    Mn-doped ZnO diluted magnetic semiconductor nanoparticles are prepared by an ultrasonic assisted sol gel process. Transmission electron microscopy shows pseudo-hexagonal nanoparticles with an average size of about 24 nm. From the analysis of X-ray diffraction,the Mn-doped ZnO nanoparticles are identified to be a wurtzite structure without any impurity phases. The magnetic properties are measured by using su perconducting quantum interference device. For the ZnO with 2 % Mn doping concentration, a good hyster esis loop indicates fine ferromagnetism with a Curie temperature higher than 350 K.

  4. Performance of food safety management systems in poultry meat preparation processing plants in relation to Campylobacter spp. contamination.

    Science.gov (United States)

    Sampers, Imca; Jacxsens, Liesbeth; Luning, Pieternel A; Marcelis, Willem J; Dumoulin, Ann; Uyttendaele, Mieke

    2010-08-01

    A diagnostic instrument comprising a combined assessment of core control and assurance activities and a microbial assessment instrument were used to measure the performance of current food safety management systems (FSMSs) of two poultry meat preparation companies. The high risk status of the company's contextual factors, i.e., starting from raw materials (poultry carcasses) with possible high numbers and prevalence of pathogens such as Campylobacter spp., requires advanced core control and assurance activities in the FSMS to guarantee food safety. The level of the core FSMS activities differed between the companies, and this difference was reflected in overall microbial quality (mesophilic aerobic count), presence of hygiene indicators (Enterobacteriaceae, Staphylococcus aureus, and Escherichia coli), and contamination with pathogens such as Salmonella, Listeria monocytogenes, and Campylobacter spp. The food safety output expressed as a microbial safety profile was related to the variability in the prevalence and contamination levels of Campylobacter spp. in poultry meat preparations found in a Belgian nationwide study. Although a poultry meat processing company could have an advanced FSMS in place and a good microbial profile (i.e., lower prevalence of pathogens, lower microbial numbers, and less variability in microbial contamination), these positive factors might not guarantee pathogen-free products. Contamination could be attributed to the inability to apply effective interventions to reduce or eliminate pathogens in the production chain of (raw) poultry meat preparations.

  5. Generic process for preparing a crystalline oxide upon a group IV semiconductor substrate

    Science.gov (United States)

    McKee, Rodney A.; Walker, Frederick J.; Chisholm, Matthew F.

    2000-01-01

    A process for growing a crystalline oxide epitaxially upon the surface of a Group IV semiconductor, as well as a structure constructed by the process, is described. The semiconductor can be germanium or silicon, and the crystalline oxide can generally be represented by the formula (AO).sub.n (A'BO.sub.3).sub.m in which "n" and "m" are non-negative integer repeats of planes of the alkaline earth oxides or the alkaline earth-containing perovskite oxides. With atomic level control of interfacial thermodynamics in a multicomponent semiconductor/oxide system, a highly perfect interface between a semiconductor and a crystalline oxide can be obtained.

  6. Highly Efficient Reproducible Perovskite Solar Cells Prepared by Low-Temperature Processing

    Directory of Open Access Journals (Sweden)

    Hao Hu

    2016-04-01

    Full Text Available In this work, we describe the role of the different layers in perovskite solar cells to achieve reproducible, ~16% efficient perovskite solar cells. We used a planar device architecture with PEDOT:PSS on the bottom, followed by the perovskite layer and an evaporated C60 layer before deposition of the top electrode. No high temperature annealing step is needed, which also allows processing on flexible plastic substrates. Only the optimization of all of these layers leads to highly efficient and reproducible results. In this work, we describe the effects of different processing conditions, especially the influence of the C60 top layer on the device performance.

  7. Highly Efficient Reproducible Perovskite Solar Cells Prepared by Low-Temperature Processing.

    Science.gov (United States)

    Hu, Hao; Wong, Ka Kan; Kollek, Tom; Hanusch, Fabian; Polarz, Sebastian; Docampo, Pablo; Schmidt-Mende, Lukas

    2016-04-23

    In this work, we describe the role of the different layers in perovskite solar cells to achieve reproducible, ~16% efficient perovskite solar cells. We used a planar device architecture with PSS on the bottom, followed by the perovskite layer and an evaporated C60 layer before deposition of the top electrode. No high temperature annealing step is needed, which also allows processing on flexible plastic substrates. Only the optimization of all of these layers leads to highly efficient and reproducible results. In this work, we describe the effects of different processing conditions, especially the influence of the C60 top layer on the device performance.

  8. Preparation of AgSnO2 composite powders by hydrothermal process

    Institute of Scientific and Technical Information of China (English)

    YANG Tian-zu; DU Zuo-juan; GU Ying-ying; QIU Xiao-yong; JIANG ming-xi

    2007-01-01

    Silver-tin oxide powders were synthesized by the hydrothermal method with Ag(NH3)2+ solution and Na2SnO3 solution as raw materials and Na2SO3 as reductant. The precipitation conditions of Na2SnO3 solution and the reduction conditions of Ag(NH3)2+ were also investigated. The powders prepared were characterized by differential thermal analysis (DTA), X-ray diffraction analysis (XRD), scanning electron microscope (SEM) and energy spectrum analysis. The results show that pH value of the solution is a key parameter in the formation of Sn(OH)4 precipitate and the reduction reaction of Ag(NH3)2+ can release H+ ions, which results in synchronous precipitation of Sn(OH)62- as Sn(OH)4. The reduction of Ag(NH3)2+ and precipitation of Na2SnO3 occur simultaneously and the coprecipitation of silver and tin oxide is reached by the hydrothermal method. The silver-tin oxide composite powders have mainly flake shape of about 0.3 μm in thickness and there exists homogeneous distribution of tin oxide and silver in the powder synthesized.

  9. Microwave absorption properties of FeSi flaky particles prepared via a ball-milling process

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chao [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Yuan, Yong [Precision Machinery Research Institute of Shanghai Space Flight Academy, Shanghai 201600 (China); Jiang, Jian-tang [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Gong, Yuan-xun [Aerospace Research Institute of Special Material and Processing Technology, Beijing 100074 (China); Zhen, Liang, E-mail: lzhen@hit.edu.cn [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); MOE Key Laboratory of Micro-system and Micro-structures Manufacturing, Harbin Institute of Technology, Harbin 150080 (China)

    2015-12-01

    Flaky FeSi alloy particles with different aspect ratio were produced via ball-milling and a subsequent annealing. The microstructure and the morphology of the particles were examined by XRD and SEM. The dc resistivity, the static magnetization properties and electromagnetic properties were measured. Particles with high aspect ratio were found possess high permittivity and permeability. On the other hand, the variation of grain size and defects density was found influence the permittivity and permeability. High specific area was believed contribute to the intense dielectric loss and the high shape magnetic anisotropy lead to high permeability in the target band. Increased electromagnetic parameters compel the absorption peak’s shift to lower frequency. Coating using flaky FeSi particles milled for 12 h as fillers presented a reflection loss of −10 dB at 2 GHz and a matching thickness of 1.88 mm. The flaky FeSi alloy particles prepared through ball-milling and annealing can be promising candidates for EMA application at 1–4 GHz band. - Highlights: • Large quantity of flakey FeSi particles were produced through a simple way. • Coatings with as-milled FeSi particles exhibit excellent EMA performance in L-S band. • Shape and size of particles can be controlled via adjusting the ball-milling time. • Shape/size along with the microstructure influence the electromagnetic properties. • Shape/size contribute more to the excellent EMA performance compared to microstructure.

  10. Preparation of chitosan nanofibers from completely deacetylated chitosan powder by a downsizing process.

    Science.gov (United States)

    Aklog, Yihun Fantahun; Dutta, Ajoy Kumar; Izawa, Hironori; Morimoto, Minoru; Saimoto, Hiroyuki; Ifuku, Shinsuke

    2015-01-01

    Chitosan nanofibers were easily prepared from fully deacetylated chitosan dry powder using a high-pressure waterjet system. From SEM observation, after 10 cycles of treatment, most of the chitosan had been reduced to homogeneous nanofibers measuring tens of nanometers. On the other hand, further mechanical treatment did not show a significant change. Relative crystallinity of chitosan nanofibers gradually decreased as the number of passes increased since high-pressure waterjet treatment damaged the crystalline region of chitosan nanofibers. The transmittance of the chitosan nanofiber slurry increased steeply, as the number of passes increased, indicating that the chitosan fibers were disintegrated effectively. Viscosity of chitosan nanofiber slurry also showed that the chitosan disintegrated well into nanofibers up to 10 passes. Above 10 passes, disintegration efficiency was saturated. The molecular weights of the nanofibers steeply decreased due to the depolymerization of chitosan by mechanical disintegration. The Young's modulus and tensile strength of chitosan nanofiber sheets were improved as the number of treatments increased, but further treatments deteriorated the tensile strength.

  11. Influence of electron beam Irradiation on PP/Piassava fiber composite prepared by melt extrusion process

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, Michelle G.; Ferreira, Maiara S.; Oliveira, Rene R.; Silva, Valquiria A.; Teixeira, Jaciele G.; Moura, Esperidiana A.B., E-mail: michellegoncalvesgomes@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    In the latest years, the interest for the use of natural fibers in materials composites polymeric has increased significantly due to their environmental and technological advantages. Piassava fibers (Attalea funifera) have been used as reinforcement in the matrix of thermoplastic and thermoset polymers. In the present work (20%, in mass), piassava fibers with particle sizes equal or smaller than 250 μm were incorporated in the polypropylene matrix (PP) no irradiated and polypropylene matrix containing 10 % and 30 % of polypropylene treated by electron-beam radiation at 40 kGy (PP/PPi/Piassava). The composites PP/Piassava and PP/PPi/Piassava were prepared by using a twin screw extruder, followed by injection molding. The composite material samples obtained were treated by electron-beam radiation at 40 kGy, using a 1.5 MeV electron beam accelerator, at room temperature, in presence of air. After irradiation treatment, the irradiated and non-irradiated specimens tests samples were submitted to thermo-mechanical tests, melt flow index (MFI), sol-gel analysis, X-Ray diffraction (XRD) and scanning electron microscopy (SEM). (author)

  12. Preparation and characterization of mesoporous lithium borosilicate material via the sol-gel process

    Energy Technology Data Exchange (ETDEWEB)

    Touati, F., E-mail: Fathi.Touati@fss.rnu.tn [Laboratoire de Chimie de la Matiere Condensee, Universite de Tunis., Institut Preparatoire aux Etudes d' Ingenieur de Tunis, 2 rue Jawaher Lel Nehru 1008 Montfleury-Tunis (Tunisia); Sediri, F. [Laboratoire de Chimie de la Matiere Condensee, Universite de Tunis., Institut Preparatoire aux Etudes d' Ingenieur de Tunis, 2 rue Jawaher Lel Nehru 1008 Montfleury-Tunis (Tunisia); Faculte des Sciences de Tunis, Universite Tunis-Elmanar, Tunis (Tunisia); Gharbi, N. [Laboratoire de Chimie de la Matiere Condensee, Universite de Tunis., Institut Preparatoire aux Etudes d' Ingenieur de Tunis, 2 rue Jawaher Lel Nehru 1008 Montfleury-Tunis (Tunisia)

    2009-05-05

    The lithium borosilicate gels were prepared from the cohydrolysis of the tetraehtylorthosilicate (Si(C{sub 2}H{sub 5}O){sub 4}) and triethylborate (B(C{sub 2}H{sub 5}O){sub 3}) by using an ethanolic solution of tetradecyltrimethylammonium bromide (TTAB) as surfactant. The Li{sup +} ions were introduced from an acidic solution of lithium carbonate (Li{sub 2}CO{sub 3}). Depending on the B/Si, Li/Si and TTAB/Si molar ratios at pH equal to 1 and at room temperature, monolithic and transparent colourless gels were obtained. The structure of the gel was investigated by infrared spectroscopy (IR), {sup 29}Si, {sup 11}B and {sup 7}Li solid-state magnetic resonance (MAS NMR) and by thermal analysis (DTA-TG). The results show the possibility of obtaining a borosilicate network via B-O-Si bonds in which Li{sup +} ions were dispersed. The adsorption-desorption isotherms of the xerogel were characteristic of mesoporous materials. These materials may provide a greater free volume through which conducting ions can move.

  13. Single step preparation of nanosilver loaded calcium phosphate by low temperature co-conversion process.

    Science.gov (United States)

    Suwanprateeb, J; Thammarakcharoen, F; Wasoontararat, K; Chokevivat, W; Phanphiriya, P

    2012-09-01

    The preparation and characterization of nanosilver loaded calcium phosphate aiming to enhance the bactericidal performance by a single step co-conversion technique using low temperature ion exchange phosphorization in combination with Tollen's reaction were performed. Silver nitrate was used as a silver ion supply source (0.001-0.1 M) and glucose was employed as a reducing agent. After conversion, surface and shell zones of all samples comprised hydroxyapatite and metallic silver as the main phases regardless of silver nitrate concentration. However, hydroxyapatite, residual calcium sulfate and monetite were found in the core zone when using silver nitrate concentration lower than 0.1 M. The microstructure of all samples comprised the distribution of spherical-shaped silver nanoparticles within the cluster of calcium phosphate nanocrystals. Total silver content (range, 0.09-6.5 %) in the converted samples was found to linearly increase with increasing silver nitrate content. Flexural modulus and strength of converted samples generally decreased with increasing silver content. Effective antibacterial activity of two selected samples (0.001 and 0.005 M AgNO(3)) against two bacterial strains (Pseudomonas aeruginosa and Staphylococcus aureus) was observed. Cytotoxic potentials by MTT assay of both samples were observed at 24 and 48 h extraction respectively.

  14. Students' Conceptual Structure, Search Process, and Outcome while Preparing a Research Proposal: A Longitudinal Case Study.

    Science.gov (United States)

    Pennanen, Mikko; Vakkari, Pertti

    2003-01-01

    Focuses on analyzing undergraduate students' information needs in terms of conceptual understanding of the topic they propose to study and its consequences for the search process and outcome. Highlights include the ASK (anomalous states of knowledge) hypothesis; subject knowledge and searching; Kuhlthau's model; conceptual structure; knowledge…

  15. Extending In Vitro Conditioning in "Aplysia" to Analyze Operant and Classical Processes in the Same Preparation

    Science.gov (United States)

    Brembs, Bjorn; Baxter, Douglas A.; Byrne, John H.

    2004-01-01

    Operant and classical conditioning are major processes shaping behavioral responses in all animals. Although the understanding of the mechanisms of classical conditioning has expanded significantly, the understanding of the mechanisms of operant conditioning is more limited. Recent developments in "Aplysia" are helping to narrow the gap in the…

  16. RHEOLOGICAL MODIFICATION OF EPOXY RESINS WITH NANO SILICA PREPARED BY THE SOL-GEL PROCESS

    Institute of Scientific and Technical Information of China (English)

    Xia Wang; Jiang Li; Cheng-fen Long; Yun-zhao Yu

    1999-01-01

    Nano silica-modified epoxy resins were synthesized by the sol-gel process. The materials have the morphological structure of nano particales dispersed in the epoxy matrix. The dispersed phase formed a physical network in the resin and thus influenced the rheological behavior greatly. However, the nano silica did not show a significant influence on the mechanical properties of the cured resins.

  17. Method of solution preparation of polyolefin class polymers for electrospinning processing included

    Science.gov (United States)

    Rabolt, John F. (Inventor); Lee, Keun-Hyung (Inventor); Givens, Steven R. (Inventor)

    2011-01-01

    A process to make a polyolefin fiber which has the following steps: mixing at least one polyolefin into a solution at room temperature or a slightly elevated temperature to form a polymer solution and electrospinning at room temperature said polymer solution to form a fiber.

  18. Inorganic oxides with mesoporosity or combined meso-and microporosity and process for the preparation thereof

    NARCIS (Netherlands)

    Shan, Z; Maschmeyer, T; Jansen, J.C.

    2001-01-01

    Bimodal inorganic material that in a pore size distribution plot has distinct mesopore and micropore peaks. A process for producing a bimodal material or a material that contains essentially only mesopores involves heating an inorganic oxide in the presence of material that bonds to the inorganic ox

  19. Inorganic oxides with mesoporosity or combined meso-and microporosity and process for the preparation thereof

    NARCIS (Netherlands)

    Shan, Z; Maschmeyer, T; Jansen, J.C.

    2001-01-01

    Bimodal inorganic material that in a pore size distribution plot has distinct mesopore and micropore peaks. A process for producing a bimodal material or a material that contains essentially only mesopores involves heating an inorganic oxide in the presence of material that bonds to the inorganic

  20. Preliminary evaluation of Am/Cm melter feed preparation process upset recovery flowsheets

    Energy Technology Data Exchange (ETDEWEB)

    Stone, M.E.

    2000-01-20

    This document summarizes the results from the development of flowsheets to recover from credible processing errors specified in TTR 99-MNSS/SE-006. The proposed flowsheets were developed in laboratory scale equipment and will be utilized with minor modifications for full scale demonstrations in the Am/Cm Pilot Facility.

  1. Coal preparation and coal cleaning in the dry process; Kanshiki sentaku to coal cleaning

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Z.; Morikawa, M.; Fujii, Y. [Okayama University, Okayama (Japan). Faculty of Engineering

    1996-09-01

    Because the wet process has a problem such as waste water treatment, coal cleaning in the dry process was discussed. When a fluidized bed (using glass beads and calcium carbonate) is utilized instead of the heavy liquid, the fluidized bed will have apparent density as the liquid does, whereas the relative relationship therewith determines whether a substance having been put into the fluidized bed will float or sink. This is utilized for coals. In addition, two powder constituents of A and B may be wanted to be separated using the fluidized extraction process (similar to the liquid-liquid extraction process). In such a case, a fluidized bed in which both constituents are mixed is added with a third constituent C (which will not mix with A, but mix well with B), where the constituents are separated into A and (B + C), and the (B + C) constituent is separated further by using a sieve. If coal has the coal content mixed with ash content and pulverized, it turns into particle groups which have distributions in grain size and density. Groups having higher density may contain more ash, and those having lower density less ash. In addition, the ash content depends also on the grain size. The ash content may be classified by using simultaneously wind classification (for density and grain size) and a sieve (for grain size). This inference may be expanded to consideration of constructing a multi-stage fluidized bed classification tower. 12 figs., 5 tabs.

  2. Lowering the environmental impact of high-kappa/ metal gate stack surface preparation processes

    Science.gov (United States)

    Zamani, Davoud

    ABSTRACT Hafnium based oxides and silicates are promising high-κ dielectrics to replace SiO2 as gate material for state-of-the-art semiconductor devices. However, integrating these new high-κ materials into the existing complementary metal-oxide semiconductor (CMOS) process remains a challenge. One particular area of concern is the use of large amounts of HF during wet etching of hafnium based oxides and silicates. The patterning of thin films of these materials is accomplished by wet etching in HF solutions. The use of HF allows dissolution of hafnium as an anionic fluoride complex. Etch selectivity with respect to SiO2 is achieved by appropriately diluting the solutions and using slightly elevated temperatures. From an ESH point of view, it would be beneficial to develop methods which would lower the use of HF. The first objective of this study is to find new chemistries and developments of new wet etch methods to reduce fluoride consumption during wet etching of hafnium based high-κ materials. Another related issue with major environmental impact is the usage of large amounts of rinsing water for removal of HF in post-etch cleaning step. Both of these require a better understanding of the HF interaction with the high-κ surface during the etching, cleaning, and rinsing processes. During the rinse, the cleaning chemical is removed from the wafers. Ensuring optimal resource usage and cycle time during the rinse requires a sound understanding and quantitative description of the transport effects that dominate the removal rate of the cleaning chemicals from the surfaces. Multiple processes, such as desorption and re-adsorption, diffusion, migration and convection, all factor into the removal rate of the cleaning chemical during the rinse. Any of these processes can be the removal rate limiting process, the bottleneck of the rinse. In fact, the process limiting the removal rate generally changes as the rinse progresses, offering the opportunity to save resources

  3. Synthesis and structural characterization of nano-hydroxyapatite biomaterials prepared by microwave processing

    Science.gov (United States)

    Ramli, Rosmamuhamadani; Arawi, Ainaa Zafirah Omar; Talari, Mahesh Kumar; Mahat, Mohd Muzamir; Jais, Umi Sarah

    2012-07-01

    Synthetic hydroxyapatite, (HA, Ca10(PO4)6(OH)2), is an attractive and widely utilized bio-ceramic material for orthopedic and dental implants because of its close resemblance of native tooth and bone crystal structure. Synthetic HA exhibits excellent osteoconductive properties. Osteoconductivity means the ability to provide the appropriate scaffold or template for bone formation. Calcium phosphate biomaterials [(HA), tri-calcium phosphate (TCP) and biphasic calcium phosphate (HA/TCP)] with appropriate three-dimensional geometry are able to bind and concentrate endogenous bone morphogenetic proteins in circulation, and may become osteoinductive and can be effective carriers of bone cell seeds. This HA can be used in bio-implants as well as drug delivery application due to the unique properties of HA. Biomaterials synthesized from the natural species like mussel shells have additional benefits such as high purity, less expensive and high bio compatibility. In this project, HA-nanoparticles of different crystallite size were prepared by microwave synthesis of precursors. High purity CaO was extracted from the natural mussel shells for the synthesis of nano HA. Dried nano HA powders were analyzed using X-Ray Diffraction (XRD) technique for the determination of crystal structure and impurity content. Scanning Electron Microscopic (SEM) investigation was employed for the morphological investigation of nano HA powders. From the results obtained, it was concluded that by altering the irradiation time, nano HA powders of different crystallite sizes and morphologies could be produced. Crystallite sizes calculated from the XRD patterns are found to be in the range of 10-55 nm depending on the irradiation time.

  4. LOTUS— Preparing Sentinel-3 Ocean and Land SAR Altimetry Processing for Copernicus

    DEFF Research Database (Denmark)

    Knudsen, Per; Andersen, Ole Baltazar; Jain, Maulik

    2014-01-01

    The Sentinel-3 satellite mission with its SRAL instrumentation contains new features compared to the conventional radar altimeter mission that form the basis for new innovative GMES products and applications that are not considered or implemented in the Copernicus services yet. To utilize the full...... potential of the new data source, new methods and processing chains need to be developed. Also, new potential Copernicus products should be developed that utilize the improved along-track resolution over both the oceans and over land. Then new operational processing, validation and delivery mechanisms need...... to be developed and implemented for generating the new dynamic products. A smooth transition from old to new products is important to ensure existing services. Finally, the take-up of the new Copernicus products by the value-adding sectors needs to be stimulated and demonstrated to ensure that they will be used...

  5. Processing of waste material of radix physochlainae for preparation of fine chemicals after extraction

    Science.gov (United States)

    He, A.; Yohannes, A.; Feng, X. T.; Yao, S.

    2017-02-01

    Waste residues of Chinese traditional medicine radix physochlainae (Huashanshen) contain a large amount of hemicelluloses after extraction. After the removal of the cellulose and lignin, main components of the solution are different degree of hydrolysis products of hemicelluloses. In the degradation process, hemicelluloses firstly become pentose, and then pentose loses 3 molecules of water and turns into furfural. This study explored a series of conditions of the method; finally the yield of furfural can reach 8.5% (calculated with the weight of raw residues) under the condition of pH of 0.2-0.3, temperature of 104-106°C, hydrolysis duration for 10 minutes. Furfural can be further processed to be resin materials.

  6. A study of ceramic-lined composite steel pipes prepared by SHS centrifugal-thermite process

    Directory of Open Access Journals (Sweden)

    Li Yuxin

    2016-01-01

    Full Text Available Al2O3 ceramic-lined steel pipe was produced by self-propagating high-temperature synthesis centrifugal thermite process (SHS C-T process from Fe2O3 and Al as the raw materials. The composition, phase separation and microstructures were investigated. The result showed the ceramic lined pipe is composed of the three main layers of various compositions, which were subsequently determined to be Fe layer, the transition layer and the ceramic layer. Fe layer is composed of austenite and ferrite, the transition layer consisted of Al2O3 ceramic and Fe, the ceramic layer consisted of the dendritic-shaped Al2O3 and the spinel-shaped structured FeAl2O4.

  7. Preparation and characterization of silk/silica hybrid biomaterials by sol-gel crosslinking process

    Energy Technology Data Exchange (ETDEWEB)

    Hou Aiqin, E-mail: aiqinhou@dhu.edu.c [National Engineering Research Center for Dyeing and Finishing of Textiles, Donghua University, 3H, 2999 North Renmin Road, Songjiang, Shanghai 201620 (China); Chen Huawei [National Engineering Research Center for Dyeing and Finishing of Textiles, Donghua University, 3H, 2999 North Renmin Road, Songjiang, Shanghai 201620 (China)

    2010-03-15

    The silk/silica hybrid biomaterials are synthesized by sol-gel crosslinking process. The chemical and morphological structures of silk/silica hybrids are investigated with micro-FT-IR spectra, X-ray diffraction, SEM, AFM, and DSC. The results show that the crosslinking reactions among inorganic nano-particles, fibroin and 2,4,6-tri[(2-epihydrin-3-bimethyl-ammonium)propyl]-1,3,5-triazine chloride (Tri-EBAC) take place during sol-gel process. The silk/silica hybrids form new molecular structures containing not only organic fibroin but also inorganic nano-silica particles. The inorganic particles are bounded to the fibroin through covalent bonds. The silk/silica hybrids can form excellent film with very even nanometer particles. The thermal properties of organic/inorganic hybrid are improved.

  8. Electronic packaging materials prepared by powder injecting molding and pressure infiltration process

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AlSiCp (65 vol.% SiC) electronic packaging materials were manufactured by powder injection molding (PIM) and pressure infiltration process in order to obtain near net-shaped parts. SiCp preformed compacts obtained by pre-sintering process at 1150 K have high strength and good appearance, and the ratio of open porosity to total porosiry is nearly 98%. The relative density of composites is bigger than 99%. The thermal conductivity of AlSiCp composites fabricated by this method is 198 W·m-1·K-1, and the coefficient of thermal expansion (CTE) is 8.0 × 10-6/K (298 K).

  9. Selecting the process arrangement for preparing the gas turbine working fluid for an integrated gasification combined-cycle power plant

    Science.gov (United States)

    Ryzhkov, A. F.; Gordeev, S. I.; Bogatova, T. F.

    2015-11-01

    Introduction of a combined-cycle technology based on fuel gasification integrated in the process cycle (commonly known as integrated gasification combined cycle technology) is among avenues of development activities aimed at achieving more efficient operation of coal-fired power units at thermal power plants. The introduction of this technology is presently facing the following difficulties: IGCC installations are characterized by high capital intensity, low energy efficiency, and insufficient reliability and availability indicators. It was revealed from an analysis of literature sources that these drawbacks are typical for the gas turbine working fluid preparation system, the main component of which is a gasification plant. Different methods for improving the gasification plant chemical efficiency were compared, including blast air high-temperature heating, use of industrial oxygen, and a combination of these two methods implying limited use of oxygen and moderate heating of blast air. Calculated investigations aimed at estimating the influence of methods for achieving more efficient air gasification are carried out taking as an example the gasifier produced by the Mitsubishi Heavy Industries (MHI) with a thermal capacity of 500 MW. The investigation procedure was verified against the known experimental data. Modes have been determined in which the use of high-temperature heating of blast air for gasification and cycle air upstream of the gas turbine combustion chamber makes it possible to increase the working fluid preparation system efficiency to a level exceeding the efficiency of the oxygen process performed according to the Shell technology. For the gasification plant's configuration and the GTU working fluid preparation system be selected on a well-grounded basis, this work should be supplemented with technical-economic calculations.

  10. Evaluation of alternative chemical additives for high-level waste vitrification feed preparation processing

    Energy Technology Data Exchange (ETDEWEB)

    Seymour, R.G.

    1995-06-07

    During the development of the feed processing flowsheet for the Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS), research had shown that use of formic acid (HCOOH) could accomplish several processing objectives with one chemical addition. These objectives included the decomposition of tetraphenylborate, chemical reduction of mercury, production of acceptable rheological properties in the feed slurry, and controlling the oxidation state of the glass melt pool. However, the DEPF research had not shown that some vitrification slurry feeds had a tendency to evolve hydrogen (H{sub 2}) and ammonia (NH{sub 3}) as the result of catalytic decomposition of CHOOH with noble metals (rhodium, ruthenium, palladium) in the feed. Testing conducted at Pacific Northwest Laboratory and later at the Savannah River Technical Center showed that the H{sub 2} and NH{sub 3} could evolve at appreciable rates and quantities. The explosive nature of H{sub 2} and NH{sub 3} (as ammonium nitrate) warranted significant mitigation control and redesign of both facilities. At the time the explosive gas evolution was discovered, the DWPF was already under construction and an immediate hardware fix in tandem with flowsheet changes was necessary. However, the Hanford Waste Vitrification Plant (HWVP) was in the design phase and could afford to take time to investigate flowsheet manipulations that could solve the problem, rather than a hardware fix. Thus, the HWVP began to investigate alternatives to using HCOOH in the vitrification process. This document describes the selection, evaluation criteria, and strategy used to evaluate the performance of the alternative chemical additives to CHOOH. The status of the evaluation is also discussed.

  11. PROCESS VARIABLES OPTIMIZATION FOR PREPARATION AND CHARACTERIZATION OF NOVEL ADSORBENT FROM LIGNOCELLULOSIC WASTE

    OpenAIRE

    Zaira Zaman Chowdhury; Sharifuddin Mohd Zain; Rashid Atta Khan,; Arash Arami-Niya,; Khalisanni Khalid

    2012-01-01

    In this study, powdered activated carbon (PAC) was produced from agricultural waste biomass of kenaf (Hibiscus cannabinus L.) core or stalk, and the process variables were optimized by applying central composite design (CCD). The influences of carbonization temperature, duration of activation, and impregnation ratio on removal percentage of copper Cu(II) ions from aqueous solution and carbon yield were investigated. A quadratic model for adsorption percentage and a 2FI model for carbon yield ...

  12. Radiochemical aspects of production and processing of radiometals for preparation of metalloradiopharmaceuticals

    OpenAIRE

    Zhernosekov, Konstantin P.

    2006-01-01

    Radiometals play an important role in nuclear medicine as involved in diagnostic or therapeutic agents. In the present work the radiochemical aspects of production and processing of very promising radiometals of the third group of the periodic table, namely radiogallium and radiolanthanides are investigated. The 68Ge/68Ga generator (68Ge, T½ = 270.8 d) provides a cyclotron-independent source of positron-emitting 68Ga (T½ = 68 min), which can be used for coordinative labelling. However, f...

  13. Magnetically assisted chemical separation (MACS) process: Preparation and optimization of particles for removal of transuranic elements

    Energy Technology Data Exchange (ETDEWEB)

    Nunez, L.; Kaminski, M.; Bradley, C.; Buchholz, B.A.; Aase, S.B.; Tuazon, H.E.; Vandegrift, G.F. [Argonne National Lab., IL (United States); Landsberger, S. [Univ. of Illinois, Urbana, IL (United States)

    1995-05-01

    The Magnetically Assisted Chemical Separation (MACS) process combines the selectivity afforded by solvent extractants with magnetic separation by using specially coated magnetic particles to provide a more efficient chemical separation of transuranic (TRU) elements, other radionuclides, and heavy metals from waste streams. Development of the MACS process uses chemical and physical techniques to elucidate the properties of particle coatings and the extent of radiolytic and chemical damage to the particles, and to optimize the stages of loading, extraction, and particle regeneration. This report describes the development of a separation process for TRU elements from various high-level waste streams. Polymer-coated ferromagnetic particles with an adsorbed layer of octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) diluted with tributyl phosphate (TBP) were evaluated for use in the separation and recovery of americium and plutonium from nuclear waste solutions. Due to their chemical nature, these extractants selectively complex americium and plutonium contaminants onto the particles, which can then be recovered from the solution by using a magnet. The partition coefficients were larger than those expected based on liquid[liquid extractions, and the extraction proceeded with rapid kinetics. Extractants were stripped from the particles with alcohols and 400-fold volume reductions were achieved. Particles were more sensitive to acid hydrolysis than to radiolysis. Overall, the optimization of a suitable NMCS particle for TRU separation was achieved under simulant conditions, and a MACS unit is currently being designed for an in-lab demonstration.

  14. PAHs in baby food: assessment of three different processing techniques for the preparation of reference materials.

    Science.gov (United States)

    Huertas-Pérez, José Fernando; Bordajandi, Luisa R; Sejerøe-Olsen, Berit; Emteborg, Håkan; Baù, Andrea; Schimmel, Heinz; Dabrio, Marta

    2015-04-01

    A feasibility study for producing a matrix reference material for selected polycyclic aromatic hydrocarbons (PAHs) in baby food is reported. A commercially available baby food, containing carrots, potatoes, tomato, white beans and meat, was spiked with the so-called 15 + 1 PAHs included in the PAHs priority list for food of the EU, at a mass fraction level of 1 μg/kg. The contaminated baby food was further processed by autoclaving, freezing or freeze drying. The homogeneity of the three materials (bottle-to-bottle variation) and their short-term (4 weeks) and long-term (18 months) stability at different temperatures were assessed. To this end, an analytical method based on a solid-liquid extraction followed by cleaning up with gel permeation chromatography (GPC) and solid phase extraction (SPE) and GC-IDMS determination, was validated in-house. It could be demonstrated that the procedure fulfilled the demands for application to the homogeneity and isochronous stability studies for the candidate reference materials targeted here. All three materials proved to be sufficiently homogeneous for the intended use. Measurements on the autoclaved material provided the most promising results in terms of envisaged shelf life, although freeze drying was also found to be a suitable processing technique for most of the investigated PAHs. These results are an important step towards the development of a matrix reference material for PAHs in a processed food matrix in a presentation very similar to routine samples.

  15. Effective removal of tetracycline from aqueous solution using activated carbon prepared from tomato (Lycopersicon esculentum Mill.) industrial processing waste.

    Science.gov (United States)

    Sayğılı, Hasan; Güzel, Fuat

    2016-09-01

    Activated carbon (TAC) prepared under optimized conditions with ZnCl2 activation from a new precursor; tomato industrial processing waste (TW), was applied as an adsorbent to remove tetracycline (TC) from aqueous solution. The factors (TAC dosage, initial TC concentration, contact time, ionic strength and solution temperature) affecting the adsorption process were examined at natural pH (5.7) of TAC-TC system in aqueous solution. Kinetic data was found to be best complied by the pseudo-second order model. The isotherm analysis indicated that the equilibrium data could be represented by the Langmuir model. The maximum adsorption capacity was identified as 500.0mgg(-1) at 308K.

  16. TEXTURAL AND CHEMICAL CHARACTERISATION OF ACTIVATED CARBONS PREPARED FROM RICE HUSK (ORYZA SATIVA USING A TWO- STAGE ACTIVATION PROCESS

    Directory of Open Access Journals (Sweden)

    JOSEPH G. COLLIN

    2008-12-01

    Full Text Available Activated carbons from agro-industrial wastes; rice husk; were prepared by physical and chemical activation using phosphoric acid as the dehydrating agent. A two-stage activation process method was used; with semi-carbonisation stage at 200oC for 15 minutes as the first stage followed by an activation stage at 500oC for 45 minutes as the second stage. The precursor material with the impregnation agent was exposed straightaway to semi-carbonization and activation temperature unlike the specific temperature progression as reported in the literature. All experiments were conducted in a laboratory scale muffle furnace under static conditions in a self generated atmosphere covering process parameters such as impregnation ratios. We found that by using this method, the AC5 had the highest iodine number and methylene blue adsorption capacity which was 506.6 mg/g and 319.0 mg/g respectively.

  17. Electroless Sliver-Plating Process in the Preparation of 103Pd-125I Hybrid Brachytherapy Seed Cores

    Directory of Open Access Journals (Sweden)

    LI Zhong-yong1,2;CHEN Bin-da1;Lv Xiao-zhou1;LU Jin-hui1;CUI Hai-ping1,2

    2014-02-01

    Full Text Available Electroless 103Pd plating and electroless Ag plating and chemical 125I depositing were took place on the surface of carbon rods in turn, which was a reliable method for the preparation of 103Pd-125I hybrid brachytherapy seed cores. 103Pd and 125I were deposited on the same substrate effectively through silver coating as a bridge. The process of electroless Ag plating was a novel and important step in the preparation of 103Pd-125I hybrid seed. In this work, the process of electroless Ag plating was studied using 0.5×3.0 mm carbon rods with palladium coating as substrate, silver-ammino complex as precursor, 110mAg as radioactive tracer, and hydrazine as reductant. The optimum conditions were AgNO3 2g/L,Na2EDTA 40 g/L,NH3•H2O 16.25%,H4N2•H2O 5‰,pH=10,t=60 min,and T=35 ℃. Sliver deposited on each carbon rod was uniform, and sliver-coating was white and smooth.

  18. Formation and Evolution of Non-dendritic Microstructures of Semisolid Alloys Prepared by Shearing/Cooling Roll Process

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The shearing/cooling roll (SCR) process was adopted to prepare semi-solid A2017 alloy. The formation and evolution of non-dendritic microstructures in semi-solid A2017 alloy were studied. It is shown that the microstructures of semi-solid billets transform from coarse dendrites into fine equiaxed grains as the pouring temperature of molten alloy decreases or roll-shoe cavity height is reduced. From the inlet to the exit of roll-shoe cavity, microstructure of semi-solid slurry near the shoe surface is in the order of coarse dendrites,degenerated dendrites or equiaxed grains, but fine equiaxed grains are near the roll surface. Microstructural evolution of semi-solid slurry prepared by SCR process is that the molten alloy nucleates and grows into dendrite firstly on the roll and shoe's surface. Under the shearing and stirring given by the rotating roll, the dendrites crush off and disperse into the melt. Under the shearing and stirring on semi-solid slurry with high volume fraction of solid, the dendrite arms fracture and form equiaxed grain microstructures.

  19. Preparation and characterization of SiC/C/SiC composites by hybrid wet/vapour processing

    Energy Technology Data Exchange (ETDEWEB)

    Licciulli, A. [Centro Nazionale Ricerca e Sviluppo Materiali, Brindisi (Italy). PASTIS; De Riccardis, F. [Centro Nazionale Ricerca e Sviluppo Materiali, Brindisi (Italy). PASTIS; Quirini, A. [Centro Nazionale Ricerca e Sviluppo Materiali, Brindisi (Italy). PASTIS; Nannetti, C.A. [ENEA-INN-NUMA C.R. Casaccia, Roma (Italy); Filacchioni, G. [ENEA-INN-NUMA C.R. Casaccia, Roma (Italy); Pilloni, L. [ENEA-INN-NUMA C.R. Casaccia, Roma (Italy); Botti, S. [ENEA-INN-FIS C.R. Frascati, Roma (Italy); Ortona, A. [INTERNOVA, Milano (Italy); Cammarota, A. [INTERNOVA, Milano (Italy)

    1997-06-01

    In this work the preparation of ceramic matrix composites with improved mechanical properties and reduced process time and cost has been investigated. A combination of liquid and vapour infiltration processes has been developed for producing SiC(fibers)/C/SiC composites. 2D-woven Nicalon fibers were coated with pyrolitic carbon and stacked to form flat panel preforms. Chemical vapour infiltration was achieved using methyltrichlorosilane (MTS) as SiC precursor in a hot wall reactor under isothermal (1050 C) and isobaric (20torr) conditions. The solution infiltration was achieved using polycarbosilane (PCS) as SiC precursor along with laser formed SiC nanopowders. Pyrolysis was performed in inert atmosphere up to 1100 C. Various combinations of the two routes were tested in order to optimise the composite properties. A short vapour infiltration run was used to form a uniform SiC deposit on the fibers that were subsequently filled by several cycles of liquid infiltration/pyrolysis. CVI was also effective to fill the submicron porosity resulting from PCS to SiC transformation. Scanning electron microscopy (SEM) is presented for the description of the morphology of the composites. Mercury porosimetry along with SEM, was used to evaluate the infiltration yield and the quality of the deposit in the various steps of the process. The mechanical behavior of the composites was investigated by flexural tests. Fibers push-in by microindentation measurements were performed to characterize the fiber/matrix interface and to investigate how it is affected by the pyrocarbon coating on the fibers. On the basis of the obtained results, a preparative process for SiC/SiC composites can be optimized by the proper use of both liquid and vapour infiltration. (orig.)

  20. Amorphous solid dispersion of cyclosporine A prepared with fine droplet drying process: Physicochemical and pharmacokinetic characterization.

    Science.gov (United States)

    Suzuki, Hiroki; Moritani, Tatsuru; Morinaga, Tadahiko; Seto, Yoshiki; Sato, Hideyuki; Onoue, Satomi

    2017-03-15

    The present study aimed to develop an amorphous solid dispersion (ASD) of cyclosporine A (CsA) by a fine droplet drying (FDD) process for improvement in oral absorption of CsA. CsA and hydroxypropyl cellulose-SSL were dissolved in 1,4-dioxane, and the solution was powdered by the FDD process to obtain the ASD formulation of CsA (ASD/CsA). The ASD/CsA was characterized in terms of morphology, particle size distribution, crystallinity, dissolution behavior, physicochemical stability, and pharmacokinetic behavior in rats. The ASD/CsA was obtained in the form of uniform spherical particles, and the span factor was calculated to be ca. 0.4. CsA in the formulation existed in an amorphous state. The ASD/CsA exhibited a higher dissolution behavior of CsA than amorphous CsA, whereas storage of the ASD/CsA under accelerated conditions led to impairment in the dissolution behavior. The constant release of CsA from non-aged ASD/CsA was observed during dissolution testing. After oral administration of CsA samples (10mg-CsA/kg) in rats, the ASD/CsA showed a high and sustained plasma concentration of CsA as evidenced by a 18-fold increase in the oral bioavailability of CsA compared with amorphous CsA. From these findings, the FDD process might be an efficacious option for the ASD formulation of CsA with enhanced biopharmaceutics properties. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Mixing process in the preparation of feed pellets at technological conditions rational parametres choice

    Directory of Open Access Journals (Sweden)

    E. S. Shentsova

    2016-01-01

    Full Text Available The mixing of ingredients – the most important process step in the manufacture of fodder pellets. The technology involves using molasses (warmed to 30–40 °C as a binder. In its composition is administered a mixture of salts of trace elements (copper sulfate, zinc sulfate, cobalt carbonate, potassium iodide, ferrous sulfate, manganese sulfate, sodium selenite, vitamins, salt, magnesium oxide, feed limestone, mono calcium phosphate and lime. Research on the development of feed pellets were carried out in laboratory conditions using experimental equipment. Mixer-reactor created the conditions for heating and temperature control of mass be mixed due to the occurring chemical reaction between water contained in the molasses, and the presence of oxides of calcium and magnesium. The choice of rational parameters of the mixing process upon receipt of fodder pellets allows to provide the high quality product with minimal energy costs. The ranges of the input information factors selected with the aid of a central rotatable uniforms-planning allowed with 56 experiments in a third-multiple replication to obtain the regression equation adequately describing the mixing process. The main factors were: the content of molasses, %; the content of calcium oxide, %; frequency of rotation of the stirrer, rpm; the content of salt in the recipe, %; the temperature of blending, °C. Output factors – productivity, kg/h; energy consumption, kWh; homogeneity of mixing, %. In the result of experiments impact factors and mathematical model of the process that allows to define output parameters within chosen ranges of variation of input factors are obtained. Greatest influence – the content of molasses in the product, the lowest – content of salt in the recipe. Efficiency of mixing hard distributed components pertaining to the most important biologically active substances was evaluated. Content (% of entered of vitamins and minerals in the pellets did not differ

  2. Techno-Economic Simulation Approach in Preparation of Employing Renewable Energies for Process Industry

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Jun Hyung; Lee, Soo bin; Hodge, Bri-Mathias; Lee, In-Beum

    2016-11-21

    The energy system of process industry are faced with a new unprecedented challenge. Renewable energies should be incorporated but single of them cannot meet its energy demand of high degree and a large quantity. This paper investigates a simulation framework to compute the capacity of multiple energy sources including solar, wind power, diesel and batteries. The framework involves actual renewable energy supply and demand profile generation and supply demand matching. Eight configurations of different supply options are evaluated to illustrate the applicability of the proposed framework with some remarks.

  3. Arts-based Research Processes in ECEC: Examples from Preparing and Conducting a Data Collection

    OpenAIRE

    Torill Vist

    2016-01-01

    In this methodological article, different concepts and possibilities related to how arts-based research processes can contribute in the early phases of ECEC research will be presented and discussed. Despite a setback of art subjects in Norwegian ECEC and early childhood teacher’s education, the field of arts still plays an important role, and is expected to be research-based. Thus, there should be a need for an aesthetical and arts-based dimension in researching ECEC, not only in the subject ...

  4. Molybdenum oxide nanosheets prepared by an anodizing-exfoliation process and observation of photochromic properties

    Science.gov (United States)

    Ranjbar, M.; Delalat, F.; Salamati, H.

    2017-02-01

    Anodizing-exfoliation of molybdenum foil was performed in 0.02 M HCl electrolyte at 30 V. In this process, the electrolyte rapidly turned into a blue colloidal solution of molybdenum oxide nanosheets with fragmented edges observed on transmission electron microscope (TEM). X-ray Diffraction (XRD) pattern of particles was free of peak while annealing at a temperature range of 100-500 °C led to formation of monoclinic (for T 300 °C) phases of MoO3. Moreover, addition of PdCl2 (0.2 g/l) salt solution caused a spontaneous bleaching of the initial blue colloid. Annealing of powders extracted from these bleached solutions with different PdCl2 concentrations at 500 °C led to a preferential growth of (0k0) orientation. X-ray photoelectron spectroscopy (XPS) revealed that the blue nanosheets solution contains mainly Mo5+ with slightly Mo6+ oxidation states and each of annealing or salt bleaching procedures can entirely convert Mo5+ to Mo6+. When the bleached solutions was exposed to KrF laser beam (λ = 248 nm) a strong photochromic coloration with a deep blue color was occurred. Regardless of Pd:Mo ratio, the primary and laser irradiated solutions showed analogues optical absorption bands in the 1-3 nm photon energy range while the photochromic process led to a broader absorption band.

  5. Characterization of microcrystalline I-layer for solar cells prepared in low temperature - plastic compatible process

    KAUST Repository

    Sliz, Rafal

    2012-06-01

    Microcrystalline silicon (mc-Si) lms deposited using a Plasma Enhanced Chemical Vapour Deposition (PECVD) process constitute an important material for manufacturing low-cost, large-area thin-lm devices, such as solar cells or thin-lm transistors. Although the deposition of electronic-grade mc-Si using the PECVD process is now well established, the high substrate temperature required (~400°C) does not lend itself to electronic devices with exible form factors fabricated on low-cost plastic substrates. In this study, we rst investigated an intrinsic mc-Si layer deposited at plastic-compatible substrate temperatures (~150°C) by characterising the properties of the lm and then evaluated its applicability to p-i-n solar cells though device characterisation. When the performance of the solar cell was correlated with lm properties, it was found that, although it compared unfavourably with mc-Si deposited at higher temperatures, it remained a very promising option. Nonetheless, further development is required to increase the overall eciency of mc-Si exible solar cells.

  6. Presence of sulphites in different types of partly processed meat products prepared for grilling

    Science.gov (United States)

    Korićanac, V.; Vranić, D.; Trbović, D.; Petronijević, R.; Parunović, N.

    2017-09-01

    In the period January 2016 to May 2017, the presence and levels of sulfite were examined in 270 samples of hamburger, sausage (various types), pljeskavica (Serbian-style meat patties of various types) and ćevapi or ćevapčići (grill kebabs) from the Serbian market. Some (12.59%) of these partly processed meat products contained sulfites, expressed as SO2, at levels above 10 mg/kg, and so did not meet requirements laid down in the National Regulation. In the remainder of the meat products (87.41%), sulfite contents were below 10 mg/kg, which is considered as “not detected”. By groups, 100% of hamburgers, 91.76% of sausages and 90.48% of pljeskavica met requirements of National Regulation. The meat product group with the biggest percentage of non-compliant meat products in which sulfites were detected was the ćevapi or ćevapčići – 18.10% of them contained sulfites. All in all, most of the partly processed meat products from the Serbian market met the National Regulation regarding sulfite content, and they were safe for consumption. Nonetheless, the high percentage of ćevapi or ćevapčići that contained sulfites leads us to conclude that regular and periodic control is necessary and one of the most important steps in ensuring safe and quality meat products for consumers.

  7. Preparation of macroporous methacrylate-based monoliths for chromatographic applications by the Reactive Gelation Process.

    Science.gov (United States)

    Bechtle, M; Butté, A; Storti, G; Morbidelli, M

    2010-07-09

    Polymeric monoliths are a relatively new separation medium for chromatographic applications. The innovative approach to produce such monoliths, the Reactive Gelation Process, presented by Marti et al. [1] for polystyrene macroporous materials is applied to a methacrylate-based material. It is shown that it is possible to create a macroporous structure by Reactive Gelation also with this polymer even if the properties of the material are different. Besides the analysis of the material by SEM and BET, several chromatographic methods are used to analyze the material properties. The ISEC experiments showed a much smaller size exclusion effect than in conventional packed beds. The permeability of the material is comparable to a packed bed with 4.13 μm particles. The column efficiency is not changing for increasing flow rates. Because of the high efficiency of the material, shorter columns are needed and therefore the comparatively low permeability is compensated. The monolith also exhibits a significant adsorption capacity for hydrophobic interaction, which makes it suitable for chromatographic purification processes.

  8. Preparation of Nd–Fe–B sintered magnets from HDDR-processed powder

    Energy Technology Data Exchange (ETDEWEB)

    Takagi, Kenta, E-mail: k-takagi@aist.go.jp [Green Innovative Magnetic Materials Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Nagoya 463-8560 (Japan); Akada, Misaho [Magnetic Materials R& D Center, Research Associations of Magnetic Materials for High-Efficiency Motors (MagHEM), Nagoya 463-8560 (Japan); Soda, Rikio; Ozaki, Kimihiro [Green Innovative Magnetic Materials Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Nagoya 463-8560 (Japan)

    2015-11-01

    The electric-current sintering technique was used to fully densify hydrogenation–disproportionation–desorption–recombination (HDDR)-processed Nd–Fe–B powder at temperatures below the grain growth temperature in order to produce high-coercive bulk magnets. However, the sintered magnets exhibited anomalous coercivity reduction that depended on sintered density. Reheating examination of the sintered magnets revealed that the reduced coercivity was increased in proportion to the heating temperature, resulting in complete recovery of coercivity. As a result, the combination of electric-current sintering and post-annealing produced sintered magnets with a coercivity of 15 kOe. Scanning and transmission electron microscopy revealed no evidence that associated the anomalous coercivity reduction and recovery with grain boundary morphology. On the other hand, various HDDR powders with different particle sizes were sintered, and finer powders yielded lower coercivity after sintering, implying that the anomalous coercivity reduction was associated with particle surface oxides of the raw powder. - Highlights: • We conduct a sintering of HDDR-processed Nd–Fe–B powder without coercivity reduction. • Rapid current sintering allows densification of this powder without grain growth. • However, the sintered magnets show an anomalous coercivity reduction phenomenon. • It is found that post-annealing completely recovers the reduced coercivity. • The anomalous coercivity reduction would be due to surface oxide of the raw powder.

  9. The ATLAS Fast Tracker Processing Units - input and output data preparation

    CERN Document Server

    Bolz, Arthur Eugen; The ATLAS collaboration

    2016-01-01

    The ATLAS Fast Tracker is a hardware processor built to reconstruct tracks at a rate of up to 100 kHz and provide them to the high level trigger system. The Fast Tracker will allow the trigger to utilize tracking information from the entire detector at an earlier event selection stage than ever before, allowing for more efficient event rejection. The connection of the system from to the detector read-outs and to the high level trigger computing farms are made through custom boards implementing Advanced Telecommunications Computing Technologies standard. The input is processed by the Input Mezzanines and Data Formatter boards, designed to receive and sort the data coming from the Pixel and Semi-conductor Tracker. The Fast Tracker to Level-2 Interface Card connects the system to the computing farm. The Input Mezzanines are 128 boards, performing clustering, placed on the 32 Data Formatter mother boards that sort the information into 64 logical regions required by the downstream processing units. This necessitat...

  10. Corrigendum to "Preparation of Nafion-sulfonated clay nanocomposite membrane for direct menthol fuel cells via a film coating process" [J. Power Sources 165 (2007) 1-2

    Science.gov (United States)

    Kim, Tae Kyoung; Kang, Myeongsoon; Choi, Yeong Suk; Kim, Hae Kyung; Lee, Wonmok; Chang, Hyuk; Seung, Doyoung

    The author regrets that the above paper was printed with an error in the title. The correct title reads: "Preparation of Nafion-sulfonated clay nanocomposite membrane for direct methanol fuel cells via a film coating process".

  11. Preparation of oxide powder by continuous oxidation process from recycled Fe-77Ni alloy scrap

    Science.gov (United States)

    Yun, J. Y.; Park, D. H.; Jung, G. J.; Wang, J. P.

    2015-12-01

    The oxidation behavior of Fe-77Ni alloy scrap was studied under a 0.2 atm oxygen partial pressure at the temperature range of 400°C to 900°C. The oxidation rate was found to be increased with an increase of temperature and followed the parabolic rate law with linearly proportional to temperature. Microstructure and cross-sectional area of the oxide layer were examined by SEM, EDX, and XRD. It could be speculated that rate-limiting step was controlled by diffusion through either the spinel structure or the NiO layer, both of which were present in this alloy during oxidation at elevated temperatures. In the long run, oxide powder less than 10 μm from Fe-77Ni alloy scrap was obtained using ball-milling and sieving processes and recovery ratio approached up to 97% for 15 hours.

  12. Preparation of Chromium Oxide Coatings on Aluminum Borate Whiskers by a Hydrothermal Deposition Process

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Aluminum borate whiskers (9Al2O32B2O3) can be used to reinforce aluminum alloys to produce light and strong composites. However, the adverse interfacial reactions between the whiskers and the aluminum alloys inhibit their practical uses; therefore, a protective coating is needed on whiskers. In this work, aluminum borate whiskers were coated with chromium-coating deposits in a hydrothermal solution containing CrCl3, Na2C4H4O6, NaPH2O2, and H3BO3. The presence of the impurity P in the hydrothermal deposits can be avoided by reducing the amount of NaPH2O2 in the coating solution. Thermodynamic analysis was used to discuss the behavior of ions in the coating process. The subsequent heating of the hydrothermal products in air at 800 ℃ yielded smooth Cr2O3 films with a thickness of 0.060.07 μm.

  13. Characterization of U Nb Zr dispersion fuel prepared by centrifugal atomization process

    Science.gov (United States)

    Park, Jong-Man; Kim, Ki-Hwan; Sohn, Dong-Seong; Kim, Chang-Kyu; Hofman, Gerard L.

    1999-02-01

    The dispersions of U-Nb-Zr alloy particles in aluminum were characterized in order to assess the applicability of this dispersion as research reactor fuel. Heat treatment revealed that the 9 wt% Nb alloy powder had, as expected, higher γ-phase stability that the 5 wt% Nb alloy powder. A lamellar structure consisting of an α-U phase and γ-phase was observed to start at the grain boundaries during heat treatment. The U-Nb-Zr alloy dispersion exhibited large volume increases during annealing when compared with similar experimental results for U 3Si, U 3Si 2 and U-Mo dispersion fuel systems. The reaction product (U,Nb,Zr)Al 3 forms preferentially by diffusion of aluminum in the α-U phase which, in turn, forms during the diffusion process as the metastable γ-phase decomposes.

  14. Enhancement of proton conductivity of sulfonated polystyrene membrane prepared by plasma polymerization process

    Indian Academy of Sciences (India)

    Bhabesh Kumar Nath; Aziz Khan; Joyanti Chutia; Arup Ratan Pal; Heremba Bailung; Neelotpal Sen Sarma; Devasish Chowdhury; Nirab Chandra Adhikary

    2014-12-01

    This work reports the achievement of higher proton conductivity of polystyrene based proton exchange membrane synthesized in a continuous RF plasma polymerization process using two precursors, styrene (C8H8) and trifluoromethane sulfonic acid (CF3SO3H). The chemical composition of the developed membranes is investigated using Fourier transform infrared spectroscopy and energy dispersive spectroscopy. Scanning electron microscopy has been used for the study of surface morphology and thickness measurement of the membrane. The membranes deposited in the power range from 0.114 to 0.318 Wcm-2 exhibit a lot of variation in the properties like proton transport, water uptake, sulfonation rate, ion exchange capacity and thermal behaviour. The proton conductivity of the membranes is achieved up to 0.6 Scm-1, measured with the help of potentiostat/galvanostat. The thermogravimetric study of the plasma polymerized membrane shows the thermal stability up to 140 °C temperature.

  15. Rheology Guided Rational Selection of Processing Temperature To Prepare Copovidone-Nifedipine Amorphous Solid Dispersions via Hot Melt Extrusion (HME).

    Science.gov (United States)

    Yang, Fengyuan; Su, Yongchao; Zhang, Jingtao; DiNunzio, James; Leone, Anthony; Huang, Chengbin; Brown, Chad D

    2016-10-03

    The production of amorphous solid dispersions via hot melt extrusion (HME) relies on elevated temperature and prolonged residence time, which can result in potential degradation and decomposition of thermally sensitive components. Herein, the rheological properties of a physical mixture of polymer and an active pharmaceutical ingredient (API) were utilized to guide the selection of appropriate HME processing temperature. In the currently studied copovidone-nifedipine system, a critical temperature, which is substantially lower (∼13 °C) than the melting point of crystalline API, was captured during a temperature ramp examination and regarded as the critical point at which the API could molecularly dissolve into the polymer. Based on the identification of this critical point, various solid dispersions were prepared by HME processing below, at, and above the critical temperature (both below and above the melting temperature (Tm) of crystalline API). In addition, the resultant extrudates along with two control solid dispersions prepared by physical mixing and cryogenic milling were assessed by X-ray diffraction, differential scanning calorimetry, hot stage microscopy, rheology, and solid-state NMR. Physicochemical properties of resultant solid dispersions indicated that the identified critical temperature is sufficient for the polymer-API system to reach a molecular-level mixing, manifested by the transparent and smooth appearance of extrudates, the absence of API crystalline diffraction and melting peaks, dramatically decreased rheological properties, and significantly improved polymer-API miscibility. Once the critical temperature has been achieved, further raising the processing temperature only results in limited improvement of API dispersion, reflected by slightly reduced storage modulus and complex viscosity and limited improvement in miscibility.

  16. Novel co-processed excipients of mannitol and microcrystalline cellulose for preparing fast dissolving tablets of glipizide

    Directory of Open Access Journals (Sweden)

    Jacob S

    2007-01-01

    Full Text Available Co-processed particles of microcrystalline cellulose and mannitol were fabricated by spray drying technique to be used as a direct compression excipient in fast dissolving tablet formulation. Microcrystalline cellulose passed through sieve no.80, having a volumetric mean diameter (d 50 of 28.35 µm, was used to form composite particles with powdered mannitol which was previously passed through sieve no. 80, in various mixing ratios. The composite particles were evaluated for their powder and compression properties. An increase in the microcrystalline cellulose proportion imparted greater compressibility to the composite particles, but the flowability of these mixtures was decreased. Although microcrystalline cellulose and mannitol have been extensively used in the formulation of fast dissolving tablets, the non-wetting property of the hard compact central core may delay the disintegration time. Optimized co-processed formulation containing mannitol and microcrystalline cellulose in the ratio of 1.25:1 was found to have optimized powder and compressibility characteristics with fast disintegrating property (< 15 s. Photomicrographs have shown that the mannitol crystals are fine and uniformly distributed in the microcrystalline matrix in spray dried form compared to physical mixture of the same combination. The fast disintegration may be due to the partial amorphization and formation of submicron particles of mannitol. These results indicated that improved fast dissolving tablets could be prepared by the co-processed mixture of microcrystalline cellulose and mannitol. Finally fast dissolving tablets of glipizide were prepared by blending with other excipients and compressed into tablets. Sensory study on disintegration time and mouth feel attributes ranked the present formulation based on grittiness, chalkiness and overall preference as the best.

  17. Preparation and characteristics of C/C composite brake disc by multi-cylindrical chemical vapor deposition processes

    Institute of Scientific and Technical Information of China (English)

    YUAN Yi-dong; ZHANG Fu-kuan; ZHOU Wan-cheng

    2005-01-01

    The C/C composite brake discs were prepared by tri-cylindrical chemical vapor deposition (CVD) process. The optimum processing parameters were as follows: deposition temperature was 830-930 ℃, the gas-flow rates of N2 and propylene were 4.8-5.2 m3/h and 5.8-6.2 m3/h, respectively, the furnace pressure was 4.5-5.5 kPa and the deposition time was 200 h.The effects of processing parameters on the densified rates, thermal-physical property and mechanical performance of C/C composite brake discs were studied. The results show that density, heat conductivity, bend strength and abrasion ratio of the multi-cylindrica brake discs are 1.02-1.78 g/cm3, 31 W/(m·K), 114 MPa and 7 μm/s, respectively, which are approximately similar to those of the single-cylindrical ones. The gas flow rate has no relation to the number of the cylinder and furnace loading. The utilization ratio of carbon can be improved by multi-cylinder CVD process without changing the characteristics of brake disc.

  18. Osteoconductivity and Hydrophilicity of TiO(2) Coatings on Ti Substrates Prepared by Different Oxidizing Processes.

    Science.gov (United States)

    Yamamoto, Dai; Kawai, Ikki; Kuroda, Kensuke; Ichino, Ryoichi; Okido, Masazumi; Seki, Azusa

    2012-01-01

    Various techniques for forming TiO(2) coatings on Ti have been investigated for the improvement of the osteoconductivity of Ti implants. However, it is not clear how the oxidizing process affects this osteoconductivity. In this study, TiO(2) coatings were prepared using the following three processes: anodizing in 0.1 M H(3)PO(4) or 0.1 M NaOH aqueous solution; thermal oxidation at 673 K for 2 h in air; and a two-step process of anodizing followed by thermal oxidation. The oxide coatings were evaluated using SEM, XRD, and XPS. The water contact angle on the TiO(2) coatings was measured as a surface property. The osteoconductivity of these samples was evaluated by measuring the contact ratio of formed hard tissue on the implanted samples (defined as the R(B-I) value) after 14 d implantation in rats' tibias. Anatase was formed by anodizing and rutile by thermal oxidation, but the difference in the TiO(2) crystal structure did not influence the osteoconductivity. Anodized TiO(2) coatings were hydrophilic, but thermally oxidized TiO(2) coatings were less hydrophilic than anodized TiO(2) coatings because they lacked in surface OH groups. The TiO(2) coating process using anodizing without thermal oxidation gave effective improvement of the osteoconductivity of Ti samples.

  19. Osteoconductivity and Hydrophilicity of TiO2 Coatings on Ti Substrates Prepared by Different Oxidizing Processes

    Directory of Open Access Journals (Sweden)

    Dai Yamamoto

    2012-01-01

    Full Text Available Various techniques for forming TiO2 coatings on Ti have been investigated for the improvement of the osteoconductivity of Ti implants. However, it is not clear how the oxidizing process affects this osteoconductivity. In this study, TiO2 coatings were prepared using the following three processes: anodizing in 0.1 M H3PO4 or 0.1 M NaOH aqueous solution; thermal oxidation at 673 K for 2 h in air; and a two-step process of anodizing followed by thermal oxidation. The oxide coatings were evaluated using SEM, XRD, and XPS. The water contact angle on the TiO2 coatings was measured as a surface property. The osteoconductivity of these samples was evaluated by measuring the contact ratio of formed hard tissue on the implanted samples (defined as the RB-I value after 14 d implantation in rats' tibias. Anatase was formed by anodizing and rutile by thermal oxidation, but the difference in the TiO2 crystal structure did not influence the osteoconductivity. Anodized TiO2 coatings were hydrophilic, but thermally oxidized TiO2 coatings were less hydrophilic than anodized TiO2 coatings because they lacked in surface OH groups. The TiO2 coating process using anodizing without thermal oxidation gave effective improvement of the osteoconductivity of Ti samples.

  20. Solidification and Re-melting Phenomena During Slurry Preparation Using the RheoMetal™ Process

    Science.gov (United States)

    Payandeh, M.; Sabzevar, Mohsen Haddad; Jarfors, A. E. W.; Wessén, M.

    2017-08-01

    The melting sequence of the enthalpy exchange material (EEM) and formation of a slurry in the RheoMetal™ process was investigated. The EEM was extracted and quenched, together with a portion of the slurry at different processing times before complete melting. The EEM initially increased in size/diameter due to melt freezing onto its surface, forming a freeze-on layer. The initial growth of this layer was followed by a period of a constant diameter of the EEM with subsequent melting and decrease of diameter. Microstructural characterization of the size and morphology of different phases in the EEM and in the freeze-on layer was made. Dendritic equiaxed grains and eutectic regions containing Si particles and Cu-bearing particles and Fe-rich particles were observed in the as-cast EEM. The freeze-on layer consisted of dendritic aluminum tilted by about 30 deg in the upstream direction, caused by the rotation of the EEM. Energy dispersion spectroscopy analysis showed that the freeze-on layer had a composition corresponding to an alloy with higher melting point than the EEM and thus shielding the EEM from the surrounding melt. Microstructural changes in the EEM showed that temperature rapidly increased to 768 K (495 °C), indicated by incipient melting of the lowest temperature melting eutectic in triple junction grain boundary regions with Al2Cu and Al5Mg8Si6Cu2 phases present. As the EEM temperature increased further the binary Al-Si eutectic started to melt to form a region of a fully developed coherent mushy state. Experimental results and a thermal model indicated that as the dendrites spheroidized near to the interface at the EEM/freeze-on layer reached a mushy state with 25 pct solid fraction, coherency was lost and disintegration of the freeze-on layer took place. Subsequently, in the absence of the shielding effect from the freeze-on Layer, the EEM continued to disintegrate with a coherency limit of a solid fraction estimated to be 50 pct.

  1. Preparation of organic/inorganic composite membranes using two types of polymer matrix via a sol-gel process

    Energy Technology Data Exchange (ETDEWEB)

    Park, Seung-Hee [School of Chemical Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea); Polymer Electrolyte Fuel Cell Research Center, Hydrogen and Fuel Cell Department, Korea Institute of Energy Research (KIER), 71-2 Jang-dong, Yuseong-gu, Daejeon 305-343 (Korea); Park, Jin-Soo; Yim, Sung-Dae; Park, Seok-Hee; Kim, Chang-Soo [Polymer Electrolyte Fuel Cell Research Center, Hydrogen and Fuel Cell Department, Korea Institute of Energy Research (KIER), 71-2 Jang-dong, Yuseong-gu, Daejeon 305-343 (Korea); Lee, Young-Moo [School of Chemical Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea)

    2008-07-01

    Organic/inorganic composite membranes were prepared using two different polymers. BPO{sub 4} particles were introduced into polymers via an in situ sol-gel process. Pre-/post-sulfonated polymers were used to prepare composite membranes as matrix. Pre-sulfonated poly(aryl ether ketone) (SPAEK-6F) copolymer was synthesized via nucleophilic aromatic substitution. Degree of sulfonation was adjusted by the percentage of sulfonated monomer. Post-sulfonated poly(ether ether ketone) (SPEEK) was prepared using concentrated sulfuric acid as sulfonation agent. The membranes were characterized in terms of the ion-exchange capacity (IEC), proton conductivity, water uptake, AFM, SEM and their thermal properties. The SPAEK-6F plain membranes showed higher proton conductivity than that of the SPEEK plain membranes at similar water uptake or IEC due to their structural difference. SEM images of the composite membranes showed that the BPO{sub 4} particles were homogenously dispersed in the polymer matrices and BPO{sub 4} particle size was greatly influenced by polymer matrix. The SPAEK-6F/BPO{sub 4} composite membranes had much smaller BPO{sub 4} particle size than the SPEEK/BPO{sub 4} composite membranes due to well dispersion of BPO{sub 4} sol-like particulates in SPAEK-6F polymer solutions forming more hydrophobic/hydrophilic nanophase than SPEEK polymer solutions. The latter containing a few micrometer-scale BPO{sub 4} particles showed higher proton conductivity than the former containing hundreds nanometer-scale BPO{sub 4} particles at similar water uptake due to the increase in freezable water and effect of particle size. (author)

  2. Preparation of organic/inorganic composite membranes using two types of polymer matrix via a sol-gel process

    Science.gov (United States)

    Park, Seung-Hee; Park, Jin-Soo; Yim, Sung-Dae; Park, Seok-Hee; Lee, Young-Moo; Kim, Chang-Soo

    Organic/inorganic composite membranes were prepared using two different polymers. BPO 4 particles were introduced into polymers via an in situ sol-gel process. Pre-/post-sulfonated polymers were used to prepare composite membranes as matrix. Pre-sulfonated poly(aryl ether ketone) (SPAEK-6F) copolymer was synthesized via nucleophilic aromatic substitution. Degree of sulfonation was adjusted by the percentage of sulfonated monomer. Post-sulfonated poly(ether ether ketone) (SPEEK) was prepared using concentrated sulfuric acid as sulfonation agent. The membranes were characterized in terms of the ion-exchange capacity (IEC), proton conductivity, water uptake, AFM, SEM and their thermal properties. The SPAEK-6F plain membranes showed higher proton conductivity than that of the SPEEK plain membranes at similar water uptake or IEC due to their structural difference. SEM images of the composite membranes showed that the BPO 4 particles were homogenously dispersed in the polymer matrices and BPO 4 particle size was greatly influenced by polymer matrix. The SPAEK-6F/BPO 4 composite membranes had much smaller BPO 4 particle size than the SPEEK/BPO 4 composite membranes due to well dispersion of BPO 4 sol-like particulates in SPAEK-6F polymer solutions forming more hydrophobic/hydrophilic nanophase than SPEEK polymer solutions. The latter containing a few micrometer-scale BPO 4 particles showed higher proton conductivity than the former containing hundreds nanometer-scale BPO 4 particles at similar water uptake due to the increase in freezable water and effect of particle size.

  3. Preparation and Properties of Sintering Additives Coated Si3N4 from Heterogeneous Nucleation Processing

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The sintering additives such as Al2O3 and/or Y2O3 were coated on the surfaces of Si3N4 particles via heterogeneousnucleation processing using a buffered pH solution as the precipitation reagent. They nucleated and grew only onthe surfaces of Si3N4 and did not form sol particles in solution by TEM observation. The isoelectric point (IEP) ofcoated Si3N4 was different from that of as-received Si3N4. The IEP of Al(OH)3-coated Si3N4 occurred at pH8.4,which is close to that of alumina. When Al(OH)3-coated Si3N4 particles were coated with Y(OH)3, the IEP of coatedSi3N4 powder shifted from pH8.4 to pH9.2, similar to that of yttria. In addition, the rheological data showed thatAl2O3 and/or Y2O3 coated Si3N4 suspension is nearly Newtonian and that added Si3N4 suspension shows a shearrate thinning behavior.

  4. Photodegradation of benzene by TiO2 nanoparticles prepared by flame CVD process

    Institute of Scientific and Technical Information of China (English)

    Hongyong Xie; Luping Zhu; Lingling Wang; Shengwen Chen; Dandan Yang; Lijun Yang; Guilan Gao; Hao Yuan

    2011-01-01

    Photodegradation of benzene at ppb levels by mixed-phase TiO2 nanoparticles,synthesized by the oxidation of TiCl4 in propane/air turbulent flame chemical vapor deposition (CVD) process,is investigated experimentally by using a tubular photoreactor with thin TiO2 films coated on the reactor wall by sedimentation. Effects of inlet benzene concentration from 10 to 300 μg/m3,futile mass fraction from about 20 to 50% and photoluminescence (PL) intensity of TiO2 nanoparticles on degradation degree are examined under the conditions of 70% relative humidity,38 μg/cm2 catalyst loading,24 mW/cm2 UV irradiation of 254 nm and 5.7 s residence time in the reactor. Based on experimental results,separation of photoinduced electron (e-) and hole (h+) pairs by rutile phase is discussed as photo-induced electron (e-) in anatase phase will migrate to rutile surface due to that the potential of conductive band of rutile is lower than that of anatase,leading to more holes ready on anatase surface for oxidation reactions.

  5. Dynamic simulation on the preparation process of thin films by pulsed laser

    Institute of Scientific and Technical Information of China (English)

    张端明; 李智华; 郁伯铭; 黄明涛; 关丽; 钟志成; 李国栋

    2001-01-01

    An ablation model of targets irradiated by pulsed laser is established. By using the simple energy balance conditions, the relationship between ablation surface location and time is derived. By an adiabatic approximation, the continuous-temperature condition, energy conservation and all boundany conditions can be established. By applying the analytical method and integral-approximation method, the solid and liquid phase temperature distributions are obtained and found to be a function of time and location. The interface of solid and liquid phase is also derived. The results are compared with the other published data. In addition, the dynamics process of pulsed laser deposition of KTN (Kta0.65Nb0.35O3) thin film is simulated in detail by using fluid dynamics theory. By combining the expression of the target ablation ratio and the dynamic equation and by using the experimental data, the effects of laser action parameters on the thickness distribution of thin film and on the thin film component characteristics are discussed. The results are in good agreement with the experimental data.

  6. Infrared Thermochromic Properties of VO2 Thin Films Prepared through Aqueous Sol-gel Process

    Institute of Scientific and Technical Information of China (English)

    LIU Dongqing; CHENG Haifeng; ZHENG Wenwei; ZHANG Chaoyang

    2012-01-01

    The stoichiometric vanadium(Ⅳ) oxide thin films were obtained by controlling the temperature,time and pressure of annealing.The thermochromic phase transition and the IR thermochromic property of 400 nm and 900 nm VO2 thin films in the 7.5 μm-14 μm region were discussed.The derived VO2 thin film samples were characterized by Raman,XRD,XPS,AFM,SEM,and DSC.The resistance and infrared emissivity of VO2 thin films under different temperature were measured,and the thermal images of films were obtained using infrared imager.The results show that the VO2 thin film annealed at 550 ℃ for 10 hours through aqueous sol-gel process is pure and uniform.The 900 nm VO2 thin film exhibits better IR thermochromic property than the 400 nm VO2 thin film.The resistance of 900 nm VO2 film can change by 4orders of magnitude and the emissivity can change by 0.6 during the phase transition,suggesting the outstanding IR thermochromic property.The derived VO2 thin film can control its infrared radiation intensity and lower its apparent temperature actively when the real temperature increases,which may be applied in the field of energy saving,thermal control and camouflage.

  7. Development of novel biocompatible hybrid nanocomposites based on polyurethane-silica prepared by sol gel process.

    Science.gov (United States)

    Rashti, Ali; Yahyaei, Hossein; Firoozi, Saman; Ramezani, Sara; Rahiminejad, Ali; Karimi, Roya; Farzaneh, Khadijeh; Mohseni, Mohsen; Ghanbari, Hossein

    2016-12-01

    Due to high biocompatibility, polyurethane has found many applications, particularly in development of biomedical devices. A new nanocomposite based on thermoset polyurethane and silica nanoparticles was synthesized using sol-gel method. Sol-gel process was fulfilled in two acidic and basic conditions by using tetraethylorthosilicate (TEOS) and trimethoxyisocyanatesilane as precursors. The hybrid films characterized for mechanical and surface properties using tensile strength, contact angle, ATR-FTIR and scanning electron microscopy. Biocompatibility and cytotoxicity of the hybrids were assessed using standard MTT, LDH and TUNEL assays. The results revealed that incorporation of silica nanoparticles was significantly improved tensile strength and mechanical properties of the hybrids. Based on the contact angle results, silica nanoparticles increased hydrophilicity of the hybrids. Biocompatibility by using human lung epithelial cell line (MRC-5) demonstrated that the hybrids were significantly less cytotoxic compared to pristine polymer as tested by MTT and LDH assays. TUNEL assay revealed no signs of apoptosis in all tested samples. The results of this study demonstrated that incorporation of silica nanoparticles into polyurethane lead to the enhancement of biocompatibility, indicating that these hybrids could potentially be used in biomedical field in particular as a new coating for medical implants.

  8. Surface morphology of PMMA/boehmite hybrid nanostructures prepared via facile one-pot process

    Science.gov (United States)

    Ghamari, Misagh; Farzi, Gholamali

    2017-08-01

    In this study, we developed the novel aqueous-based PMMA/AlOOH hybrid by a one-pot process starting from their relevant precursors in a controlled manner. Starting chemical reactions directly from precursors and the sequence of adding reactants provide the possibility towards enhancing the homogeneity of the final product. Inorganic and organic segments were made compatible by means of oleic acid as a coupling agent. Boehmite to PMMA weight ratio as the main parameter was varied from 0 to 18% and the morphology, particle size, size distribution, and topography map of hybrids was shown to be composition dependent. Final PMMA/Bo nanohybrids were characterized using FTIR to confirm the chemical interactions between inorganic and organic segments. TEM analysis showed that nanohybrid particles with irregular shapes containing inorganic particles dispersed in the organic matrix are formed with an average diameter which depends on boehmite content. The presence of phase transformation of Bo makes PMMA/Bo hybrids significantly thermally stable. According to AFM topography map analysis and relevant Gaussian fit function, the roughness of nanocomposite, the size of hybrid nanoparticles and deviation from the mean value (size) were increased as Bo increases from 0 to 18.

  9. Parallel processing streams for motor output and sensory prediction during action preparation.

    Science.gov (United States)

    Stenner, Max-Philipp; Bauer, Markus; Heinze, Hans-Jochen; Haggard, Patrick; Dolan, Raymond J

    2015-03-15

    Sensory consequences of one's own actions are perceived as less intense than identical, externally generated stimuli. This is generally taken as evidence for sensory prediction of action consequences. Accordingly, recent theoretical models explain this attenuation by an anticipatory modulation of sensory processing prior to stimulus onset (Roussel et al. 2013) or even action execution (Brown et al. 2013). Experimentally, prestimulus changes that occur in anticipation of self-generated sensations are difficult to disentangle from more general effects of stimulus expectation, attention and task load (performing an action). Here, we show that an established manipulation of subjective agency over a stimulus leads to a predictive modulation in sensory cortex that is independent of these factors. We recorded magnetoencephalography while subjects performed a simple action with either hand and judged the loudness of a tone caused by the action. Effector selection was manipulated by subliminal motor priming. Compatible priming is known to enhance a subjective experience of agency over a consequent stimulus (Chambon and Haggard 2012). In line with this effect on subjective agency, we found stronger sensory attenuation when the action that caused the tone was compatibly primed. This perceptual effect was reflected in a transient phase-locked signal in auditory cortex before stimulus onset and motor execution. Interestingly, this sensory signal emerged at a time when the hemispheric lateralization of motor signals in M1 indicated ongoing effector selection. Our findings confirm theoretical predictions of a sensory modulation prior to self-generated sensations and support the idea that a sensory prediction is generated in parallel to motor output (Walsh and Haggard 2010), before an efference copy becomes available.

  10. Secondary Ion Mass Spectrometry Imaging of Molecular Distributions in Cultured Neurons and Their Processes: Comparative Analysis of Sample Preparation

    Science.gov (United States)

    Tucker, Kevin R.; Li, Zhen; Rubakhin, Stanislav S.; Sweedler, Jonathan V.

    2012-11-01

    Neurons often exhibit a complex chemical distribution and topography; therefore, sample preparation protocols that preserve structures ranging from relatively large cell somata to small neurites and growth cones are important factors in secondary ion mass spectrometry (SIMS) imaging studies. Here, SIMS was used to investigate the subcellular localization of lipids and lipophilic species in neurons from Aplysia californica. Using individual neurons cultured on silicon wafers, we compared and optimized several SIMS sampling approaches. After an initial step to remove the high salt culturing media, formaldehyde, paraformaldehyde, and glycerol, and various combinations thereof, were tested for their ability to achieve cell stabilization during and after the removal of extracellular media. These treatments improved the preservation of cellular morphology as visualized with SIMS imaging. For analytes >250 Da, coating the cell surface with a 3.2 nm-thick gold layer increased the ion intensity; multiple analytes previously not observed or observed at low abundance were detected, including intact cholesterol and vitamin E molecular ions. However, once a sample was coated, many of the lower molecular mass (cell stabilization with glycerol and 4 % paraformaldehyde. The sample preparation methods described here enhance SIMS imaging of processes of individual cultured neurons over a broad mass range with enhanced image contrast.

  11. Environmentally benign process for the preparation of antimicrobial α-methylene-β-hydroxy-γ-butyrolactone (tulipalin B) from tulip biomass.

    Science.gov (United States)

    Nomura, Taiji; Hayashi, Emiko; Kawakami, Shohei; Ogita, Shinjiro; Kato, Yasuo

    2015-01-01

    Tulipalin B (α-methylene-β-hydroxy-γ-butyrolactone, PaB) is an antimicrobial natural product occurring in tulip (Tulipa gesneriana). PaB is directly formed from the precursor glucose ester 6-tuliposide B (PosB) by endogenous Pos-converting enzyme (TCE). Despite the potential usefulness of antibacterial PaB in various industrial applications, lack of facile synthetic schemes hampers its practical use. Herein, we describe an environmentally benign and facile process for the preparation of PaB using tulip biomass materials based on one-step enzyme reaction catalyzed by TCE without the use of petroleum-derived solvents. By screening 115 tulip cultivars, we found three elite cultivars, which accumulated PosB almost exclusively in flower tissues. The flower extracts with aqueous ethanol were partially purified with activated charcoal and subjected to the enzyme reaction with reusable immobilized TCE prepared from bulb crude extracts. The reaction was completed in a few hours at room temperature, and PaB was purified with activated charcoal and ethanol in a batch-wise manner.

  12. Influence of pH on the Property of Apatite-type Lanthanum Silicates Prepared by Sol-gel Process

    Institute of Scientific and Technical Information of China (English)

    SHI Qingle; LU Lihua; ZENG Yanwei; ZHANG Hua

    2012-01-01

    The apatite-type lanthanum silicates with formula La9.33Si6O26 are prepared by sol-gel process.The homogeneity of the sol affected by pH value of the solution is investigated.The viscosity of the sols slightly increases first and then increases abruptly because the predominant reaction mechanism changes from hydrolysis reaction to condensation reaction.In addition,the onset time of the increase for the viscosity shortens from pH1 to pH 4.The gelation time decreases with increasing pH of the solution.Therefore,the pH of the sols should be less than 4 to form gel.The sol with initial pH 2 shows maximum value of zeta potential and maximum stability.For the sample with initial pH 2,pure apatite-type lanthanum silicates La9.33Si6O26 have been successfully prepared after the dried gel is calcined at 1 000 ℃.In addition,this sample sintered at 1 550 ℃exhibits the highest ionic conductivity.The activation energies are all less than 0.90 eV.

  13. THERMAL, MECHANICAL, AND MOISTURE ABSORPTION PROPERTIES OF WOOD-TiO2 COMPOSITES PREPARED BY A SOL-GEL PROCESS

    Directory of Open Access Journals (Sweden)

    Xiaoqing Wang,

    2012-01-01

    Full Text Available Wood-TiO2 (titania composites were prepared by a sol-gel process, in which wood was impregnated with the precursor solutions prepared from tetrabutyl titanate (TBT, followed by a curing step. The surface morphology and moisture absorption behavior of the wood composites, as well as their thermal and mechanical performances, were examined. Environmental scanning electron microscopy (ESEM analysis revealed that TiO2 gels were deposited principally in the cell lumens and partly in the cell walls, as confirmed by the energy dispersive X-ray (EDX analysis. By this inorganic modification, the hygroscopicity of wood was significantly reduced and its dimensional stability was improved consequently. Greater amounts of TiO2 gel deposited in the cell lumens were not helpful in enhancing the hygroscopicity of wood. Thermal analysis (TG-DTA showed that the incorporation of TiO2 gel retarded the thermal decomposition of wood matrix and improved the thermal stability of wood. The incorporated inorganic gel seemed to stiffen the wood cell walls, as indicated by the increased resistance of the wood composites to deformation and collapse in compression.

  14. Visible light induced electron transfer process over nitrogen doped TiO(2) nanocrystals prepared by oxidation of titanium nitride.

    Science.gov (United States)

    Wu, Zhongbiao; Dong, Fan; Zhao, Weirong; Guo, Sen

    2008-08-30

    Nitrogen doped TiO(2) nanocrystals with anatase and rutile mixed phases were prepared by incomplete oxidation of titanium nitride at different temperatures. The as-prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), core level X-ray photoelectron spectroscopy (CL XPS), valence band X-ray photoelectron spectroscopy (VB XPS), UV-vis diffuse reflectance spectra (UV-vis DRS), and visible light excited photoluminescence (PL). The photocatalytic activity was evaluated for photocatalytic degradation of toluene in gas phase under visible light irradiation. The visible light absorption and photoactivities of these nitrogen doped TiO(2) nanocrystals can be clearly attributed to the change of the additional electronic (N(-)) states above the valence band of TiO(2) modified by N dopant as revealed by the VB XPS and visible light induced PL. A band gap structure model was established to explain the electron transfer process over nitrogen doped TiO(2) nanocrystals under visible light irradiation, which was consistent with the previous theoretical and experimental results. This model can also be applied to understand visible light induced photocatalysis over other nonmetal doped TiO(2).

  15. Preparation of soil nutrient amendment using white mud produced in ammonia-soda process and its environmental assessment

    Institute of Scientific and Technical Information of China (English)

    SHI Lin; LUO Han-jin

    2009-01-01

    A novel method to prepare soil nutrient amendment by calcining a mixture of white mud and potassium feldspar and its environmental assessment were investigated. Under the optimal conditions of a blending mass ratio of 70-30 for white mud to potassium feldspar, a calcination temperature of 1 000 ℃, a calcination time of 1.5 h and spherulitic diameter of 2.0 cm, the calcined product, as a soil nutrient amendment, could be prepared with the following nutrient composition (mass fraction): K2O 4.16%, CaO 23.43%, MgO 5.04%, SiO_2 22.92%, SO_4~(2-) 3.71%, and Cl- 3.87% in 0.1 mol/L citric acid solution. The concentrations of heavy metals in the calcined product and the emission concentrations of harmful gases from a mixture of white mud and potassium feldspar during calcination process could qualify the National Standards without causing secondary environmental pollution.

  16. Improvement of microtome cutting process of carbon nanotube composite sample preparation for TEM analysis

    Science.gov (United States)

    Trayner, Sarah

    As research progresses towards nanoscale materials, there has become a need for a more efficient and effective way to obtain ultra-thin samples for imaging under transmission electron microscope (TEM) for atomic resolution analysis. There are various methods used to obtain thin samples (epoxy composites, are of poor quality due to the sample cutting difficulties. Such poor quality samples are characterized by uneven sample thicknesses, objective overlapping, overall darkness due to large thickness, and defects such as cutting scratches. This research is a continuous effort to study and improve the ultra-microtome cutting technique to provide an effective and reliable approach of obtaining an ultra-thin (25-50 nm) cross section of a CNT/polymer composite for high resolution TEM analysis. Improvements were achieved by studying the relationships between the chosen cutting parameters, sample characteristics and TEM image quality. From this information, a cutting protocol was established so that ultra-thin sample slices can be achieved by different microtome operators for high resolution TEM analysis. In addition, a custom tool was created to aid in the sample collection process. In this research, three composite samples were studied for both microtome cutting and TEM analysis: 1) Unidirectional (UD) IM7/BMI composite; 2) Single-layer CNT buckypaper (BP)/epoxy nanocomposite; 3) 3-layer CNT BP/BMI nanocomposite. The resultant TEM images revealed a clear microstructure consisting of amorphous resin and graphite crystalline packing. UD IM7/BMI composite TEM results did not reveal an interfacial region resulting in a need for even thinner sliced cross sections. TEM results for the single-layer CNT BP/epoxy nanocomposite revealed the alignment direction of the nanotubes and numerous stacks of CNT bundles. In addition, there was visible flattening of CNT packing into dumbbell shapes similar to results obtain by Alan Windle. TEM results for the 3-layer CNT BP/BMI nanocomposite

  17. Contributions in the Preparation and Processing of Composite Material Type Silumin 3 - Reinforced Matrix with S235JR Steel Mesh

    Directory of Open Access Journals (Sweden)

    Remus Belu-Nica

    2015-07-01

    Full Text Available In the paper are presented concrete data on developing technological batches of metal composite material (MCM type Silumin 3-reinforced matrix with steel mesh S235JR, with the indicating of the parameter and of the distinct stages of work. The samples from prepared batches were cut along and across by water jet abrasive process and were subjected to a destructive testing program and microstructural examination, obtaining results in concordance with the desired quality. The abrasive material used for cut was GMA granite with the average mesh of 80, the particle size ranging between 150-300 µm, density 2300 kg/m3 and melting point 1240°C.

  18. A series of spinel phase cathode materials prepared by a simple hydrothermal process for rechargeable lithium batteries

    Science.gov (United States)

    Liang, Yan-Yu; Bao, Shu-Juan; Li, Hu-Lin

    2006-07-01

    A series of spinel-structured materials have been prepared by a simple hydrothermal procedure in an aqueous medium. The new synthetic method is time and energy saving i.e., no further thermal treatment and extended grinding. The main experimental process involved the insertion of lithium into electrolytic manganese dioxide with glucose as a mild reductant in an autoclave. Both the hydrothermal temperature and the presence of glucose play the critical roles in determining the final spinel integrity. Particular electrochemical performance has also been systematically explored, and the results show that Al 3+, F - co-substituted spinels have the best combination of initial capacity and capacity retention among all these samples, exhibited the initial capacity of 115 mAh/g and maintained more than 90% of the initial value at the 50th cycle.

  19. A Novel Process to Prepare Chitosan Macrospheres without Shrinkage and its Application to Immobilize β-Galactosidase

    Directory of Open Access Journals (Sweden)

    Su-Fang Sun

    2009-01-01

    Full Text Available A new process for the preparation of chitosan macrospheres, which was simple and practicable, was suggested in this paper and various chitosans with different molecular weight were used as materials to immobilize β-galactosidase and the chitosan macrospheres with the lowest molecular weight (500 000 was selected as enzyme immobilization carrier based on the highest enzyme activity. In order to overcome the shrinkage of chitosan during drying, the wet macrospheres obtained was treated by 30% glycerol solution for 1 h before drying and the results showed that the dried chitosan macrospheres obtained could keep almost the same structure as its wet form, which was very important for chitosan as enzyme carrier in industry. Finally, β-galactosidase from Aspergillus oryzae was immobilized on above dry chitosan macrospheres and a satisfactory result of the immobilized enzyme was obtained in enzyme activity yield, pH stability, thermal stability, operational stability, Michaelis constants Km and the maximum velocity (Vm

  20. Phosphorus- and sulfur-containing oligopiperylene as an additive to lubricating oils and process for its preparation

    Energy Technology Data Exchange (ETDEWEB)

    Beresnev, V.V.; Kafiyatullina, S.T.; Kirpichnikov, P.A.; Stepanov, E.A.; Yunusov, O.A.

    1980-02-25

    For the purpose of strengthening the antioxidant, antiwear, and antiseizing properties of additives for lubricating oils it is proposed to use as additive a phosphorus- and sulfur-containing oligopiperylene of the formula, (iso-C/sub 3/H/sub 7/O)/sub 2/P(S)O-(CH/sub 2/CH=CHCH(CH/sub 3/)/sub 6/)(CH/sub 2/CHACH/sub 2/CH(CH/sub 3/))/sub 4/OP(S)(O-C/sub 3/H/sub 7/-iso)/sub 2/, where A = SP(S)(O-C/sub 3/H/sub 7/ -iso)/sub 2/, and a process for preparing it has been developed. The oligopiperylenediol is caused to react with diisopropyldithiophosphoric acid in benzene medium in the presence of benzoyl peroxide at a temperature of 80-82/sup 0/.

  1. Preparation and Characterisation of Hydroxyapatite Coatings on Nanotubular TiO2 Surface Obtained by Sol-Gel Process.

    Science.gov (United States)

    Shin, Jin-Ho; Kim, Jung-Hwa; Koh, Jeong-Tae; Lim, Hyun-Pil; Oh, Gye-Jeong; Lee, Seok-Woo; Lee, Kwang-Min; Yun, Kwi-Dug; Park, Sang-Won

    2015-08-01

    Hydroxyapatite (HA) coating on titanium dioxide (TiO2) nanotubular surface has been developed to complement the defects of both TiO2 and HA. A sol-gel processing technique was used to coat HA on TiO2 nanotubular surface. All the titanium discs were blasted with resorbable blast media (RBM). RBM-blasted Ti surface, anodized Ti surface, and sol-gel HA coating on the anodized Ti surface were prepared. The characteristics of samples were observed using scanning electron microscopy and X-ray photoemission spectroscopy. Biologic responses were evaluated with human osteosarcoma MG63 cells in vitro. The top of the TiO2 nanotubes was not completely covered by HA particles when the coating time was less than 60 sec. It was demonstrated the sol-gel derived HA film was well-crystallized and this enhanced biologic responses in early stage cell response.

  2. Rx for NCLEX-RN success: reflections on development of an effective preparation process for senior baccalaureate students.

    Science.gov (United States)

    March, Karen S; Ambrose, Janice M

    2010-01-01

    This article highlights the process employed to support and facilitate student preparation for NCLEX-RN success at a baccalaureate institution that experienced a decline in pass rates subsequent to increased enrollment. The multifaceted approach emphasizes individualized attention; strategies to augment student self-confidence, enhancement of critical thinking skills, self-assessment of test-taking abilities, development of a feasible study plan utilizing learned effective study techniques; and the acknowledgment of barriers and identification of specific methods to overcome them. In place since spring 2006, consistently improved measurable outcomes are evident without the added student stress of consequences for failing to attain a benchmark score on an end-of-program examination.

  3. Bright blue photoluminescence from a mixed tin and manganese oxide xerogel prepared via sol-hydrothermal-gel process

    Institute of Scientific and Technical Information of China (English)

    Xiang Xia; Cheng Xiao-Feng; He Shao-Bo; Yuan Xiao-Dong; Zheng Wan-Guo; Li Zhi-Jie; Liu Chun-Ming; Zhou Wei-Lie; Zu Xiao-Tao

    2011-01-01

    A new blue photoluminescent material,a mixed tin and manganese oxide xerogel,is prepared via sol-hydrothermalgel process assisted by citric acid.The composition xerogel exhibits strong blue emission at room temperature,with an emission maximum at 434 nm under short (234 nm) or long-wavelength (343 nm) ultraviolet excitation.The photoluminescent excitation spectrum of the mixed tin and manganese oxide xerogel,monitored at an intensity maximum wavelength of 434 nm of the emission,consists of two excitation peaks at 234 nm and 343 nm.With heat treatment temperature increasing from 110 ℃ to 200 ℃,the blue emission intensity increases remarkably,whereas it is almost completely quenched after being treated at 300 ℃.The carbon impurities in the mixed tin and manganese oxide xerogel,confirmed by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy,should be responsible for the bright blue photoluminescence.

  4. Enhanced magnetic properties in Nd-Fe-B magnets prepared by spark plasma sintering via die-upsetting process

    Institute of Scientific and Technical Information of China (English)

    HU Zhihua; CHU Linhua; LI Jun; LIU Ying

    2011-01-01

    The magnetic properties and microstructure of Nd-Fe-B magnets prepared by spark plasma sintering with different die-upsetting processes were investigated.The results showed that the optimum magnetic properties of die-upset Nd-Fe-B magnets were obtained at 680 ℃ when the die-upset level was 60%,and the degree of magnetic alignment was 0.84.The microstructures showed that the coarse grains occurred predominantly within certain areas,and abnormal grain growth was not observed within the major areas of well-aligned grains.There existed many small spherical grains,which stacked together and were not aligned during die upsetting when the deformation temperature was 650 ℃.These small spherical grains grew up,and were aligned when the deformation temperature increased from 650 to 680 ℃,which could improve the crystallographic alignment of die-upset Nd-Fe-B magnets.

  5. Preparation of porous hollow silica spheres via a layer-by-layer process and the chromatographic performance

    Science.gov (United States)

    Wei, Xiaobing; Gong, Cairong; Chen, Xujuan; Fan, Guoliang; Xu, Xinhua

    2017-03-01

    Hollow silica spheres possessing excellent mechanical properties were successfully prepared through a layer-by-layer process using uniform polystyrene (PS) latex fabricated by dispersion polymerization as template. The formation of hollow SiO2 micro-spheres, structures and properties were observed in detail by zeta potential, SEM, TEM, FTIR, TGA and nitrogen sorption porosimetry. The results indicated that the hollow spheres were uniform with particle diameter of 1.6 μm and shell thickness of 150 nm. The surface area was 511 m2/g and the pore diameter was 8.36 nm. A new stationary phase for HPLC was obtained by using C18-derivatized hollow SiO2 micro-spheres as packing materials and the chromatographic properties were evaluated for the separation of some regular small molecules. The packed column showed low column pressure, high values of efficiency (up to about 43 000 plates/m) and appropriate asymmetry factors.

  6. Process optimization for the preparation of straw feedstuff for rearing yellow mealworms (Tenebrio molitor L.) in BLSS

    Science.gov (United States)

    Li, Leyuan; Liu, lh64. Hong

    2012-07-01

    It has been confirmed in our previous work that in bioregenerative life support systems, feeding yellow mealworms (Tenebrio molitor L.) using fermented straw has the potential to provide good animal protein for astronauts, meanwhile treating with plant wastes. However, since the nitrogen content in straw is very low, T. molitor larvae can not obtain sufficient nitrogen, which results in a relatively low growth efficiency. In this study, wheat straw powder was mixed with simulated human urine before fermentation. Condition parameters, e.g. urine:straw ratio, moisture content, inoculation dose, fermentation time, fermentation temperature and pH were optimized using Taguchi method. Larval growth rate and average individual mass of mature larva increased significantly in the group of T. molitor larvae fed with feedstuff prepared with the optimized process.

  7. Optimization of Preparation Process for Processed Cheese Fortified with Blueberry Pulp%蓝莓果肉再制干酪工艺优化

    Institute of Scientific and Technical Information of China (English)

    王英; 李浩; 田雪娇; 张建强; 张丽萍

    2012-01-01

    This paper deals with process optimization for the preparation of processed cheese fortified with blueberry pulp from fast-ripened cheese and blueberry pulp using one-factor-at-a-time and orthogonal array design methods.The optimal formulation for processed cheese was skimmed milk powder 8%,butter 10%,blueberry pulp 20%,emulsifying salt 1.0%,xanthan gum 0.3%,salt 1.5%,and purified water 35%,which were simultaneously heated at 85 ℃ and stirred for 7 min.%以快速成熟干酪、蓝莓果浆为主要原料,通过单因素和正交试验对蓝莓果肉再制干酪工艺进行优化,确定最佳配方为:加入脱脂奶粉8%、黄油10%、蓝莓果浆20%、乳化盐1.5%、黄原胶0.3%、食盐1.5%、纯净水35%、加热温度85℃、搅拌时间7min。

  8. Fe{sub 2}O{sub 3} nanopowders prepared by a thermal plasma process for water oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dongeun; Choi, Yong-Wook; Na, Ye-Seul; Choi, Soo-Suk; Park, Dong-Wha; Choi, Jinsub, E-mail: jinsub@inha.ac.kr

    2015-08-15

    Highlights: • Hematite nanopowders with a high purity were synthesized by a DC thermal plasma process. • Fe{sub 3}O{sub 4} is formed during the formation of Fe{sub 2}O{sub 3} by thermal plasma with iron and oxygen sources. • Hematite nanopowders with a high purity show higher PEC performance compared to mixed oxides. - Abstract: Hematite (Fe{sub 2}O{sub 3}) nanopowders were synthesized from commercially available micro-sized iron powders by a DC thermal plasma process at atmospheric pressure. The micro-sized iron powders were vaporized in the plasma region, after which the plasma processing equipment was rapidly quenched, resulting in the formation of iron nanopowders with a size of less than 100 nm. Subsequently, the iron nanopowders were heated to convert hematite with a high purity, which was then formed into a thin film with a binder for preparation of electrodes for photoelectrochemical water oxidation. Iron oxide nanopowders were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), particle size analysis (PSA) and transmission electron microscopy (TEM). The photoelectrochemical properties of the Fe{sub 2}O{sub 3} film were characterized in 1 M NaOH under AM 1.5 conditions.

  9. Evaluation of aeration pretreatment to prepare an inoculum for the two-stage hydrogen and methane production process.

    Science.gov (United States)

    Giordano, Andrea; Sarli, Valentina; Lavagnolo, Maria Cristina; Spagni, Alessandro

    2014-08-01

    This study evaluates the effect of aeration pretreatment to prepare an inoculum for H₂ and CH₄ production in a two-stage process. Moreover, the biochemical hydrogen potential and biochemical methane potential of waste from the food industry in a two-stage process was assessed. The results confirmed the possibility of using an aerobic stress for selecting a hydrogen-producing inoculum. The inoculum was fairly stable since no hydrogenotrophic-methanogenic activity was observed in 25 days. The yields measured using glucose as substrate were of approximately 160 and 280 N mL(H₂) g(COD⁻¹) of glucose for hydrogen and methane, respectively, which are in agreement with other studies using heat-shock for the pretreatment of the inoculum. When waste of the food industry (wheat milling) was used as substrate, a lower H₂ yield was achieved by the aerobically-pretreated inoculum if compared to heat-shock; however, when combined with methane production in a two-stage process, much higher CH₄ yield was achieved.

  10. Preparation, melting behavior and thermal stability of poly(lactic acid)/poly(propylene carbonate) blends processed by vane extruder

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Wei, E-mail: zw55624@163.com; Chen, Rongyuan; Zhang, Haichen; Qu, Jinping, E-mail: jpqu@scut.edu.cn [National Engineering Research Center of Novel Equipment for Polymer Processing, South China University of Technology, Guangzhou 510640 (China)

    2016-03-09

    Poly (lactic acid) (PLA)/Poly (propylene carbonate) (PPC) blends were prepared by vane extruder which is a type of novel polymer processing extruder based on elongation force field. Scanning electron microscope (SEM), differential scanning calorimetry (DSC) and thermogravimetric (TG) were used respectively to analyze the compatibility, the melting behavior and thermal stability properties of PLA/PPC blends affected by the different content of PPC. The results showed that with the increase of the PPC content, the glass transition temperature of PLA was reduced, and the glass transition temperature of PPC was increased, which indicated that PLA and PPC had partial compatibility. The cold crystallization temperature of PLA increased with the increase of the PPC content, which showed that PPC hindered the cold crystallization process of PLA. The addition of PPC had little impact on the melting process of PLA, and the melting temperature of PLA was almost kept the same value. Thermogravimetric analysis showed that the thermal stability of PPC was worse than that of PLA, the addition of PPC reduced the thermal stability of PLA.

  11. Antibacterial property of CuCrO{sub 2} nanopowders prepared by a self-combustion glycine nitrate process

    Energy Technology Data Exchange (ETDEWEB)

    Nien, Yung-Tang, E-mail: ytnien@nfu.edu.tw [Deparment of Materials Science and Engineering, National Formosa University, Yunlin, 63201, Taiwan (China); Hu, Mon-Ru [Deparment of Materials Science and Engineering, National Formosa University, Yunlin, 63201, Taiwan (China); Chiu, Te-Wei [Department of Materials and Mineral Resources Engineering, National Taipei University of Technology, Taipei, 10608, Taiwan (China); Chu, Jaw-Shiow [Bioresource Collection and Research Center, Food Industry Research and Development Institute, Hsinchu, 30062, Taiwan (China)

    2016-08-15

    Porous CuCrO{sub 2} nanopowders were prepared via glycine nitrate process (GNP) at 175 °C in ambient air. The X-ray diffraction patterns showed a pure delafossite phase of CuCrO{sub 2} with numerous broad peaks, indicating a crystallite size of approximately 20 nm. The surface area of the CuCrO{sub 2} nanopowders was larger than 50 m{sup 2}/g, nearly 100 times greater than that of bulk powders (0.47 m{sup 2}/g). Pathogenic Gram-negative bacteria Escherichia coli (E. coli) were chosen as the antibacterial evaluation indicators for both the nanopowders and bulk powders. The results showed that 1750 ppm nanopowders inhibited the growth of E. coli. As a control, the bulk powders showed a normal growth profile. The antibacterial property of the CuCrO{sub 2} nanopowders can be attributed to the extremely large surface area, which induces rapid release of Cu ions and strong adhesion of nanopowders to bacteria. - Highlights: • CuCrO{sub 2} nanopowders was prepared by low-temperature glycine nitrate process. • 1250–1500 ppm of CuCrO{sub 2} nanopowders were found to depress the growth of Escherichia coli. • Bulk powders by the solid state reaction exhibited no antibacterial property. • The antibacterial property of nanopowders was attributed to rapid Cu ion releases. • Heavy adhesion of nanopowders to bacteria also resulted in antibacterial property.

  12. Biodiesel fuel from rapeseed oil as prepared in supercritical methanol

    Energy Technology Data Exchange (ETDEWEB)

    Saka, S.; Kusdiana, D. [Kyoto University, Kyoto (Japan). Dept. of Socio-Environmental Energy Science, Graduate School of Energy Science

    2001-01-01

    Transesterification reaction of rapeseed oil in supercritical methanol was investigated without using any catalyst. An experiment has been carried out in the batch-type reaction vessel preheated at 350 and 400{degree}C and at a pressure of 45-65 MPa, and with a molar ratio of 1:42 of the rapeseed oil to methanol. It was consequently demonstrated that, in a preheating temperature of 350{degree}C, 240 s of supercritical treatment of methanol was sufficient to convert the rapeseed oil to methyl esters and that, although the prepared methyl esters were basically the same as those of the common method with a basic catalyst, the yield of methyl esters by the former was found to be higher than that by the latter. In addition, it was found that this supercritical methanol process requires the shorter reaction time and simpler purification procedure because of the unused catalyst. 16 refs., 9 figs., 2 tabs.

  13. E-Beam Synthesis of Optical Organic-Inorganic Waveguide Film, prepared by Sol-gel Processing Method

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Eun; Chon, Jina; Cho, Byung Gun; Noh, Seung Ju; Kwon, Yong Ku [Inha Univ., Incheon (Korea, Republic of)

    2011-07-01

    Optical organic-inorganic waveguide materials were synthesized by non-hydrolytic sol-gel reaction. To synthesize an alkoxysilane precursor, 3-glycidoxypropyl trimethoxysilane was reacted with azo-type materials at elevated temperature. This precursor was then reacted with 4.4-diphenol to synthesize the organic-inorganic hybrids by sol-gel reaction. The reaction mixture was then heat-treated for thermal condensation and methanol as a byproduct was also eliminated. After product has added 2.2-dimethoxy-2-phenylacetophenone for using UV-curing, the thin film was prepared by spin coating or bulk dropwise methode on the ITO substrate. It was cured by UV-curing methode and their patterned morphology and electro-optical properties were precisely measured. Also, E-beam process was used another cuing methode. This process was more efficient curing method than UV-curing methode. Because E-beam was very short curing time and very strong irradiation power. The detail results will be given in the meeting.

  14. Potato powders prepared by successive cooking-process depending on resistant starch content affect the intestinal fermentation in rats.

    Science.gov (United States)

    Kawakami, Sakura; Han, Kyu-Ho; Araki, Takahiro; Ohba, Kiyoshi; Wakabayashi, Tatsuya; Shimada, Kenichiro; Fukushima, Michihiro

    2017-02-01

    The effects of resistant starch (RS) in dry potato powders prepared by various processes on intestinal fermentation in rats were assessed. Rats were fed raw potato powder (RP), blanched potato powder (BP), steamed potato powder (SP), or drum-dried potato powder (DP) for 4 weeks. The cecal RS content was significantly higher in the RP group than in the control diet (CN) group and other dry potato powder groups. Cecum pH was significantly lower in the RP group compared to the CN group, and was also significantly lower than that in the SP, BP, and DP groups. Lactic acid bacteria levels in the RP group were significantly higher than those in the CN group, and levels in the SP group also increased relative to the control group. Lactobacillus levels in the RP group were higher than in the CN and other dry potato powder groups. Cecal short-chain fatty acid (SCFA) concentrations in the RP group followed by the SP group exhibited significantly higher levels relative to the control levels. Dry potato powders containing RS produced during the cooking process may represent a useful food material that increases intestinal concentrations of SCFA and enhances the growth of certain lactic acid bacteria.

  15. Microorganism Nutrition Processes as a General Route for the Preparation of Bionic Nanocomposites Based on Intractable Polymers.

    Science.gov (United States)

    Valentini, L; Bon, S Bittolo; Pugno, N M

    2016-08-31

    In this paper the fermentation process activated by living microorganisms of the baker's yeast is proposed as a facile assembly method of hybrid nanoparticles at liquid interface. Water dispersion of commercial baker's yeast extract used for bread production, graphene nanoplatelets (GNPs), and carbon nanotubes (CNTs) were added to oil/water interface; when the yeast is activated by adding sugar, the byproduct carbon dioxide bubbles migrate from the water phase to the oil/water interface generating a floating nanostructured film at liquid interface where it is trapped. Starting from this simple method, we propose a general approach for the stabilization of intractable poly(etheretherketone) polymeric particles with GNPs and CNTs at immiscible liquid interface. This process allowed the formation of sintered porous composites with improved mechanical properties. The porous structure of the composites gave rise to a low thermal conductivity making them good candidates for thermal insulating applications. Liquid absorption by these porous composites has been also reported. We believe that this new approach may have applications in the large scale fabrication of nanomaterials and is particularly suited for the preparation of nanocomposites starting from polymers that are intractable by solvent casting.

  16. Block containing contaminated ion exchange resins and preparation process. Bloc contenant des resines echangeuses d'ions contaminees et son procede de preparation

    Energy Technology Data Exchange (ETDEWEB)

    Kertesz, C.; Da Silva, P.

    1993-01-08

    The invention concerns a block containing contaminated ion exchange resins for storage in a repository. Ion exchange resins are incorporated, after water saturation, in a composite matrix made of hardened epoxide resin and cement chosen among Clinker slag cements and slag-ashes cements. The presence of cement in composite matrix allows to limit the temperature in such block below 63 degree C, during their preparation.

  17. The influence of cavity preparation design on fracture strength and mode of fracture of laboratory-processed composite resin restorations.

    Science.gov (United States)

    Fonseca, Rodrigo Borges; Fernandes-Neto, Alfredo Julio; Correr-Sobrinho, Lourenco; Soares, Carlos Jose

    2007-10-01

    Removal of large amounts of sound tooth structure may result in a weakened restored tooth. Nevertheless, removal of tooth structure for cuspal coverage has been recommended to protect teeth restored with laboratory-processed composite resin (LPCR) from fracture. The purpose of this study was to evaluate the influence of different cavity preparation designs on fracture strength and modes of fracture of teeth restored with LPCR. Ninety anatomically similar human third mandibular molars were selected. There were 2 experimental factors, occlusal isthmus width (narrow versus wide) and cuspal coverage (inlay, 1-cusp onlay, 2-cusp onlay, and all-cusp onlay), and 1 control group that received no treatment, resulting in 9 groups (n=10). Indirect composite resin (SR Adoro) restorations were manufactured and adhesively cemented with Adper Single Bond 2 and Rely-X ARC. A compressive loading test (0.5 mm/min) was performed. The modes of fracture were classified according to 4 categories. One-way and 2-way ANOVA followed by Tukey-HSD test were used to statistically analyze the fracture load data (alpha =.05). The statistical analysis failed to show significant differences among restored groups but showed differences between these groups and the control group (P = .001). Two-way ANOVA failed to show any difference when considering the occlusal isthmus width alone (P = .98), cuspal coverage (P = .273), or the interaction between these factors (P = .972). Several teeth had fractures affecting a great amount of both restoration and tooth structure. This in vitro study showed restored teeth having similar fracture strength and fracture modes, suggesting that with the tested preparation designs, there is no advantage of cuspal coverage to protect LPCR restored teeth from fracture.

  18. Room temperature plasma oxidation: A new process for preparation of ultrathin layers of silicon oxide, and high dielectric constant materials

    Energy Technology Data Exchange (ETDEWEB)

    Tinoco, J.C. [Seccion de Electronica del Estado Solido, Depto. Ingenieria Electrica, CINVESTAV-IPN, Av. IPN, No. 2508, CP 07730, Mexico D.F. (Mexico) and Facultad de Ingenieria y Arquitectura, Universidad de San Martin de Porres (FIA-USMP), Av. La Fontana 1250, La Molina, Lima 12 (Peru)]. E-mail: jcesartinoco@yahoo.com.mx; Estrada, M. [Seccion de Electronica del Estado Solido, Depto. Ingenieria Electrica, CINVESTAV-IPN, Av. IPN, No. 2508, CP 07730, Mexico D.F. (Mexico)]. E-mail: mestrada@mail.cinvestav.mx; Baez, H. [Seccion de Electronica del Estado Solido, Depto. Ingenieria Electrica, CINVESTAV-IPN, Av. IPN, No. 2508, CP 07730, Mexico D.F. (Mexico); Cerdeira, A. [Seccion de Electronica del Estado Solido, Depto. Ingenieria Electrica, CINVESTAV-IPN, Av. IPN, No. 2508, CP 07730, Mexico D.F. (Mexico)

    2006-02-21

    In this paper we present basic features and oxidation law of the room temperature plasma oxidation (RTPO), as a new process for preparation of less than 2 nm thick layers of SiO{sub 2}, and high-k layers of TiO{sub 2}. We show that oxidation rate follows a potential law dependence on oxidation time. The proportionality constant is function of pressure, plasma power, reagent gas and plasma density, while the exponent depends only on the reactive gas. These parameters are related to the physical phenomena occurring inside the plasma, during oxidation. Metal-Oxide-Semiconductor (MOS) capacitors fabricated with these layers are characterized by capacitance-voltage, current-voltage and current-voltage-temperature measurements. Less than 2.5 nm SiO{sub 2} layers with surface roughness similar to thermal oxide films, surface state density below 3 x 10{sup 11} cm{sup -2} and current density in the expected range for each corresponding thickness, were obtained by RTPO in a parallel-plate reactor, at 180 mW/cm{sup 2} and pressure range between 9.33 and 66.5 Pa (0.07 and 0.5 Torr) using O{sub 2} and N{sub 2}O as reactive gases. MOS capacitors with TiO{sub 2} layers formed by RTPO of sputtered Ti layers are also characterized. Finally, MOS capacitors with stacked layers of TiO{sub 2} over SiO{sub 2}, both layers obtained by RTPO, were prepared and evaluated to determine the feasibility of the use of TiO{sub 2} as a candidate for next technology nodes.

  19. Antimony (V) Oxide Adsorbed on a Silica-Zirconia Mixed Oxide Obtained by the Sol-Gel Processing Method: Preparation and Acid Properties

    OpenAIRE

    Zaitseva,Galina; Gushikem,Yoshitaka

    2002-01-01

    The preparation, degree of dispersion, thermal stability and Lewis and Brønsted acidity of antimony (V) oxide adsorbed on SiO2/ZrO2 mixed oxide, previously prepared by the sol-gel processing method, are described herein. The samples SiO2/ZrO2/Sb2O5, with compositions (in wt %): (a) Zr= 8.1 and Sb= 6.3; (b) Zr= 14.9 and Sb= 11.4, were prepared. Scanning electron microscopy images connected to a X-ray energy dispersive spectrometer showed that both metals, Zr and Sb, were highly dispersed ...

  20. Preparation of natural pyrite nanoparticles by high energy planetary ball milling as a nanocatalyst for heterogeneous Fenton process

    Energy Technology Data Exchange (ETDEWEB)

    Fathinia, Siavash [Department of Mining Engineering, Faculty of Engineering and Technology, Imam Khomeini International University, Qazvin (Iran, Islamic Republic of); Research Laboratory of Advanced Water and Wastewater Treatment Processes, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of); Fathinia, Mehrangiz [Research Laboratory of Advanced Water and Wastewater Treatment Processes, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of); Rahmani, Ali Akbar [Department of Mining Engineering, Faculty of Engineering and Technology, Imam Khomeini International University, Qazvin (Iran, Islamic Republic of); Khataee, Alireza, E-mail: a_khataee@tabrizu.ac.ir [Research Laboratory of Advanced Water and Wastewater Treatment Processes, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of)

    2015-02-01

    Graphical abstract: - Highlights: • Pyrite nanoparticles were successfully produced by planetary ball milling process. • The physical and chemical properties of pyrite nanoparticles were fully examined. • The degradation of AO7 was notably enhanced by pyrite nanoparticles Fenton system. • The influences of basic operational parameters were investigated using CCD. - Abstract: In the present study pyrite nanoparticles were prepared by high energy mechanical ball milling utilizing a planetary ball mill. Various pyrite samples were produced by changing the milling time from 2 h to 6 h, in the constant milling speed of 320 rpm. X-ray diffraction (XRD), scanning electron microscopy (SEM) linked with energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FT-IR) analysis and Brunauer–Emmett–Teller (BET) were performed to explain the characteristics of primary (unmilled) and milled pyrite samples. The average particle size distribution of the produced pyrite during 6 h milling was found to be between 20 nm and 100 nm. The catalytic performance of the different pyrite samples was examined in the heterogeneous Fenton process for degradation of C.I. Acid Orange 7 (AO7) solution. Results showed that the decolorization efficiency of AO7 in the presence of 6 h-milled pyrite sample was the highest. The impact of key parameters on the degradation efficiency of AO7 by pyrite nanoparticles catalyzed Fenton process was modeled using central composite design (CCD). Accordingly, the maximum removal efficiency of 96.30% was achieved at initial AO7 concentration of 16 mg/L, H{sub 2}O{sub 2} concentration of 5 mmol/L, catalyst amount of 0.5 g/L and reaction time of 25 min.

  1. Study on "dry process" to prepare reinforced fluoro plastic%增强氟塑料干法制备工艺研究

    Institute of Scientific and Technical Information of China (English)

    白龙腾; 姜潮

    2012-01-01

    对生产增强氟塑料的原材料P202和FR104两种聚四氟乙烯树脂性能进行了对比,采用“干法”制备工艺并对工艺参数进行改进,生产出FS-20d和FS-35d增强氟塑料。生产制品测试结果表明:“干法”制备工艺配方稳定、生产工艺稳定,制品的耐磨性能、耐高温性能、致密性、均匀性和相分散性均优于“湿法”制备工艺制品。%The properties of two kinds of polyterafluoroethylene resins (P202 and FR104) for preparing the reinforced fluoro plastic were compared. The "dry process" to prepare the reinforced fluoro plastic was chosen to improve the process parameters, and adopted to produce two new kinds of reinforced fluoro plastic (FS-20d, FS-35d). The test results of the final products indicate that the preparation process formula and production process of "dry process" are stable, and the wear-resis- ting property, high temperature resistance, compactness, uniformity and phase dispersion of the new products prepared with "dry process" are better than the products yield by "wet process" .

  2. 赤泥耕土制备技术%Preparation Process of Cultivated Soil Rehabilitated from Red Mud

    Institute of Scientific and Technical Information of China (English)

    彭光菊; 张健伟; 张磊; 饶玉学

    2011-01-01

    Taking the plant waste as modifier of red mud, the preparation process of cultivated soil rehabilitated from red mud with wide applicability, which can treat with a large number of red mud was investigated. The basic principle of this technique was that the harmful elements in red mud are diluted by and made a complex ( sequestration) process with humic acids produced by the hydrolysis and fermentation of plant waste and with the alkaline in humus and red mud so as to improve the porosity for the red mud and supply with the needs for plant growth. Good results have been achieved to prepare the cultivated soil rehabilitated from red mud by using com stalks, bagasse and wastewater, weeds as modifier of red mud respectively in the tests, Among these, the test with com stalks as a modifier showed that the plants grew normally in the cultivated soil with the bulk density of 1. 3 g/cm3, and pH value at 7.9.%以植物性废料为赤泥的改性剂,研发了适用性广、可大量消纳赤泥的赤泥耕土制备技术.该技术的基本原理是利用植物废料水解、发酵产生的腐殖酸和腐殖质中和赤泥的碱性、稀释并络(鳌)合赤泥中的有害元素、提高赤泥的疏松度、为赤泥添加植物生长所需养分.分别以玉米秸秆、蔗渣和废醪液、杂草为赤泥改性剂进行的赤泥耕土制备试验均取得了良好效果,其中以玉米秸秆为改性剂的试验表明,所得赤泥耕土的容重为1.3 g/cm3,pH值为7.9,养分增加,植物可在其中正常生长.

  3. Droplet centrifugation, droplet DNA extraction, and rapid droplet thermocycling for simpler and faster PCR assay using wire-guided manipulations

    Directory of Open Access Journals (Sweden)

    You David J

    2012-09-01

    Full Text Available Abstract A computer numerical control (CNC apparatus was used to perform droplet centrifugation, droplet DNA extraction, and rapid droplet thermocycling on a single superhydrophobic surface and a multi-chambered PCB heater. Droplets were manipulated using “wire-guided” method (a pipette tip was used in this study. This methodology can be easily adapted to existing commercial robotic pipetting system, while demonstrated added capabilities such as vibrational mixing, high-speed centrifuging of droplets, simple DNA extraction utilizing the hydrophobicity difference between the tip and the superhydrophobic surface, and rapid thermocycling with a moving droplet, all with wire-guided droplet manipulations on a superhydrophobic surface and a multi-chambered PCB heater (i.e., not on a 96-well plate. Serial dilutions were demonstrated for diluting sample matrix. Centrifuging was demonstrated by rotating a 10 μL droplet at 2300 round per minute, concentrating E. coli by more than 3-fold within 3 min. DNA extraction was demonstrated from E. coli sample utilizing the disposable pipette tip to cleverly attract the extracted DNA from the droplet residing on a superhydrophobic surface, which took less than 10 min. Following extraction, the 1500 bp sequence of Peptidase D from E. coli was amplified using rapid droplet thermocycling, which took 10 min for 30 cycles. The total assay time was 23 min, including droplet centrifugation, droplet DNA extraction and rapid droplet thermocycling. Evaporation from of 10 μL droplets was not significant during these procedures, since the longest time exposure to air and the vibrations was less than 5 min (during DNA extraction. The results of these sequentially executed processes were analyzed using gel electrophoresis. Thus, this work demonstrates the adaptability of the system to replace many common laboratory tasks on a single platform (through re-programmability, in rapid succession (using droplets

  4. Hoecodems technology in comparison with conventional separation processes for coal preparation; Die Hoecodems-Technologie im Vergleich zu konventionellen Sortierverfahren in der Steinkohlenaufbereitung

    Energy Technology Data Exchange (ETDEWEB)

    Wilczynski, P. [Hoelter GmbH, Gladbeck (Germany)

    1999-05-01

    The new Hoecodems technology is presented and compared with conventional separation processes in coal preparation. It is clearly shown that new preparation processes - including the Hoecodems technology - operate extremely economically in respect of the selected particle size range for the complementary separation processes. This applies particularly to the achievable Ep values. A comparison of the investment and operating costs drawn up for a new Polish coal preparation plant with a throughput of 1200 tph shows that, as a result of the compact plant construction possible with the application of the new preparation process incorporating Hoecodems technology, the investment costs only amount to around 85% and the operating costs only about 91% of those required for a conventional preparation plant. (orig.) [Deutsch] Die neue Hoecodems-Technologie wird vorgestellt und mit konventionellen Sortierverfahren in der Steinkohlenaufbereitung verglichen. Dabei wird herausgestellt, dass neue Aufbereitungsverfahren - zu denen auch die Hoecodems-Technik gehoert - im Hinblick auf den gewaehlten Korngroessenbereich der einander zugeordneten Sortierverfahren besonders wirtschaftlich arbeiten. Das gilt besonders fuer die erzielbaren Ep-Werte. Ein Investitions- und Betriebskostenvergleich fuer eine polnische Steinkohlenaufbereitungsanlage mit einem Durchsatz von 1200 t/h zeigt aufgrund der kompakten Bauweise bei Einsatz des neuen Aufbereitungsverfahrens einschliesslich der Hoecodems-Technologie, dass die Investitionskosten nur etwa 85% und die Betriebskosten nur etwa 91% einer konventionellen Aufbereitungsanlage betragen. (orig.)

  5. A novel route to prepare pH- and temperature-sensitive nanogels via a semibatch process.

    Science.gov (United States)

    Zhang, Qingsong; Zha, Liusheng; Ma, Jinghong; Liang, Borun

    2009-02-15

    A novel method via a semibatch process in the absence of surfactant has been adopted to prepare pH- and temperature-sensitive nanogels. The shape, charge distribution, temperature, and pH-induced volume phase transition behavior of the latexes were investigated by scanning electronic microscopy, zeta potentials, dynamic laser light scattering, and UV/vis spectroscopy. It was found that, in the absence of surfactant, with increasing the amount of AAc from 5 to 20 mol% of N-isopropylacrylamide (NIPAM), the hydrodynamic diameters (D(H)) decrease from 230 to 60 nm. With increasing pH value from 3 to 11, the D(H) values increase slightly, which is different than the dramatic increase seen when using a conventional batch method with a range from 680 to 1700 nm. However, at pH 3, the turbidity curves of these kinds of particles increase dramatically at temperatures between 33 and 37 degrees C, while remaining constant at first and then increasing directly at pH 11. Furthermore, the distribution of carboxylic groups located not only on the interior but also on the exterior of colloidal particles as a result of adoption of the semibatch method, other than simple surface distribution of poly(NIPAM-co-AAc) latexes via the batch method.

  6. Preparation of the Iron Oxide Red from the Converter Dust by the Magnetic Separation and Roasting Process

    Science.gov (United States)

    Guo, Z. J.; Li, S. Q.; Yang, C. Q.

    2017-05-01

    Preparation of iron oxide red (α-Fe2O3) from the converter dust by the superconductivity high gradient magnetic separation (S-HGMS) and roasting process was investigated in the paper. The basic properties of the dust were studied by the X Ray Fluorescence, the chemical analysis and the X Ray Diffraction methods. The results showed that the raw dust mainly contained elements of Fe‵O‵Si‵Ca, the iron content of the raw dust was 61.80%, and there were ferrous phases of Fe3O4, α-Fe2O3, Fe2(SiO4) and CaFe(Si2O6) in the raw dust. Under the optimum conditions of magnetic field intensity of 1.8T, the dispersion agent of 30mg/L and velocity of 500mL/min, the powders absorbed by the magnetic medium mainly contained Fe3O4 and α-Fe2O3, and the iron content of powders absorbed was up to 65.90%. The Fe2+ content of the powders absorbed under the optimum magnetic conditions dropped to 0.25% from 19.10% after roasting of fifty minutes, and the iron content of powders absorbed under the optimum magnetic conditions fell to 64% due to oxidation, and the Fe3O4 was removed. Finally the α-Fe2O3 content was up to 91.07% in the iron oxide red.

  7. Spray drying of a poorly water-soluble drug nanosuspension for tablet preparation: formulation and process optimization with bioavailability evaluation.

    Science.gov (United States)

    Sun, Wei; Ni, Rui; Zhang, Xin; Li, Luk Chiu; Mao, Shirui

    2015-06-01

    Spray drying experiments of an itraconazole nanosuspension were conducted to generate a dry nanocrystal powder which was subsequently formulated into a tablet formulation for direct compression. The nanosuspension was prepared by high pressure homogenization and characterized for particle-size distribution and surface morphology. A central composite statistical design approach was applied to identify the optimal drug-to-excipient ratio and spray drying temperature. It was demonstrated that the spray drying of a nanosuspension with a mannitol-to-drug mass ratio of 4.5 and at an inlet temperature of 120 °C resulted in a dry powder with the smallest increase in particle size as compared with that of the nanosuspension. X-ray diffraction results indicated that the crystalline structure of the drug was not altered during the spray-drying process. The tablet formulation was identified by determining the micromeritic properties such as flowability and compressibility of the powder mixtures composed of the spray dried nanocrystal powder and other commonly used direct compression excipients. The dissolution rate of the nanocrystal tablets was significantly enhanced and was found to be comparable to that of the marketed Sporanox®. No statistically significant difference in oral absorption between the nanocrystal tablets and Sporanox® capsules was found. In conclusion, the nanosuspension approach is feasible to improve the oral absorption of a BCS Class II drug in a tablet formulation and capable of achieving oral bioavailability equivalent to other well established oral absorption enhancement method.

  8. Protein encapsulated core-shell structured particles prepared by coaxial electrospraying: investigation on material and processing variables.

    Science.gov (United States)

    Zamani, Maedeh; Prabhakaran, Molamma P; Thian, Eng San; Ramakrishna, Seeram

    2014-10-01

    Biodegradable polymeric particles have been extensively investigated for controlled drug delivery of various therapeutic agents. 'Coaxial' electrospraying was successfully employed in this study, to fabricate core-shell PLGA particles containing bovine serum albumin (BSA) as the model protein, and the results were also compared to particles prepared by 'emulsion' electrospraying. Two different molecular weights of PLGA were employed to encapsulate the protein. Solution properties and processing parameters were found to influence the morphology of the core-shell particles. Depending on the type of solvent used to dissolve the polymer as well as the polymer concentration and molecular weight, the mean diameter of the particles varied between 3.0 to 5.5 μm. Fluorescence microscopic analysis of the electrosprayed particles using FITC-conjugated BSA demonstrated the core-shell structure of the developed particles. The encapsulation efficiency and release behavior of BSA was influenced by shell:core feeding ratio, protein concentration, and the electrospraying method. The encapsulation efficiency of BSA within the core-shell particles of high and low molecular weight PLGA was found 15.7% and 25.1% higher than the emulsion electrosprayed particles, respectively. Moreover, the total amount of BSA released from low molecular weight PLGA particles was significantly higher than high molecular weight PLGA particles within 43 days of release studies, with negligible effect on encapsulation efficiency. The technique of coaxial electrospraying has high potential for encapsulation of susceptible protein-based therapeutic agents such as growth factors for multiple drug delivery applications.

  9. Hysteretic Behavior upon Light Soaking in Perovskite Solar Cells Prepared via Modified Vapor-Assisted Solution Process.

    Science.gov (United States)

    Liu, Chong; Fan, Jiandong; Zhang, Xing; Shen, Yanjiao; Yang, Lin; Mai, Yaohua

    2015-05-06

    Recently, the organic-inorganic hybrid perovskite solar cells exhibit rapidly rising efficiencies, while anomalous hysteresis in perovskite solar cells remains unsolvable. Herein, a high-quality perovskite thin film is prepared by a modified vapor-assisted solution process, which is a simple but well-controllable method proven to be capable of producing a thin film with full surface coverage and grain size up to micrometers. The as-fabricated perovskite solar cell has efficiency as high as 10.2%. The hysteresis effects of both planar and mesoscopic TiO2-based perovskite solar cells have been comprehensively studied upon illumination. The results demonstrate that mesoporous-based perovskite cells combined with remarkable grain size are subject to alleviating the hysteresis effects in comparison to the planar cells. Likewise, mesoscopic TiO2-based perovskite cells perform independently of illumination and bias conditions prior to the measurements, whereas the planar cells display a reversible behavior of illumination and applied bias-dependent I-V curves. The present study would refer strip road for the stability study of the perovskite solar cells.

  10. Preparation and characterization of quercetin-loaded silica microspheres stabilized by combined multiple emulsion and sol-gel processes

    Directory of Open Access Journals (Sweden)

    Kim Young Ho

    2015-01-01

    Full Text Available Despite exhibiting a wide spectrum of cosmeceutical properties, flavonoids and related compounds have some limitations related to their stability and solubility in distilledwater. In this project, we prepared silica microspheres using a novel method that uses polyol-in-oil-in-water (P/O/W emulsion and sol-gel methods as techniques for stabilizing quercetin. A stable microsphere suspension was successfully preparedusing a mixed solvent system comprising a polyol-phase medium for performing the sol-gel processing of tetraethyl orthosilicate (TEOS as an inorganic precursor with outer water phase. The morphology of the microsphere was evaluated using a scanning electron microscope (SEM, which showed a characteristic spherical particle shape with a smooth surface. Furthermore, SEM/EDSanalysis of a representative microsphere demonstrated that the inner structure of the silica microspheres was filled with quercetin. The mean diameter of the microsphere was in the range 20.6-35.0 μm, and the encapsulation efficiency ranged from 17.8% to 27.5%. The free and encapsulated quercetin samples were incubated in separateaqueous solutions at 25 and 42°C for 28 days. The residualcontent of the quercetin encapsulated by silica microspheres was 82% at 42°C. In contrast, that of the free quercetin stored at 42°C decreased to ~24%.

  11. Processing, Mechanical and Optical Properties of Additive-Free ZrC Ceramics Prepared by Spark Plasma Sintering

    Directory of Open Access Journals (Sweden)

    Clara Musa

    2016-06-01

    Full Text Available In the present study, nearly fully dense monolithic ZrC samples are produced and broadly characterized from microstructural, mechanical and optical points of view. Specifically, 98% dense products are obtained by Spark Plasma Sintering (SPS after 20 min dwell time at 1850 °C starting from powders preliminarily prepared by Self-propagating High-temperature Synthesis (SHS followed by 20 min ball milling. A prolonged mechanical treatment up to 2 h of SHS powders does not lead to appreciable benefits. Vickers hardness of the resulting samples (17.5 ± 0.4 GPa is reasonably good for monolithic ceramics, but the mechanical strength (about 250 MPa up to 1000 °C could be further improved by suitable optimization of the starting powder characteristics. The very smoothly polished ZrC specimen subjected to optical measurements displays high absorption in the visible-near infrared region and low thermal emittance at longer wavelengths. Moreover, the sample exhibits goodspectral selectivity (2.1–2.4 in the 1000–1400 K temperature range. These preliminary results suggest that ZrC ceramics produced through the two-step SHS/SPS processing route can be considered as attractive reference materials for the development of innovative solar energy absorbers.

  12. Preparation of Al2-xYxW3O12 powders by citrate sol-gel process

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hai-jun; ZHANG Qing; JIA Quan-li; YE Guo-tian

    2008-01-01

    Al2-xYxW3O12 (x=0.2, 0.5, 0.8, 1.0, 1.2, 1.5, 1.7 and 2.0) powders were synthesized by citrate sol-gel process. The concentration of species in a citric solution for preparing Al2-xYxW3O12 powders was calculated. The powders were characterized by differential thermal analysis(DTA), thermogravimetry(TG), X-ray diffractometry(XRD) and scanning electron microscopy(SEM), respectively. No solid solution of Al2-xYxW3O12 is formed with x values varying from 0 to 2.0. The maximum solid solubility of Y2O33 in Al2W3O12 and Al2O33 in Y2W3O12 is less than 0.5. Y2W3O12 easily absorbs water in air and forms a composition of 2W3O12·3.2H20, and Al2W3O12 forms Al2W3O12·0.17H2O in the same condition.

  13. Preparation of SiC{sub f}/SiC composites by the slip infiltration and transient eutectoid (SITE) process

    Energy Technology Data Exchange (ETDEWEB)

    Novak, Sasa, E-mail: sasa.novak@ijs.s [Department for Nanostructured Materials, Jozef Stefan Institute, Slovenian Fusion Association (SFA) EURATOM-MHEST (Slovenia); Drazic, Goran; Koenig, Katja; Ivekovic, Aljaz [Department for Nanostructured Materials, Jozef Stefan Institute, Slovenian Fusion Association (SFA) EURATOM-MHEST (Slovenia)

    2010-04-30

    A novel ceramic processing route 'SITE', composed of ceramic slip infiltration in a SiC-fibre preform and the low-temperature sintering of a SiC-based matrix using a transient eutectoid, has been introduced as an optional way of producing low-activation, SiC-based, ceramic-matrix composites for fusion applications. The matrix material's composition was developed on the basis of sintering studies using submicron and nanosized SiC powders and various low-activation precursors for the transient eutectoid secondary phase. Three different compositions of the secondary phase were investigated: SiO{sub 2}-Y{sub 2}O{sub 3}-P{sub 2}O{sub 5}, SiO{sub 2}-MgO-P{sub 2}O{sub 5} and SiO{sub 2}-Al{sub 2}O{sub 3}-P{sub 2}O{sub 5}. The last of these resulted in the most promising material, which was obtained by sintering in controlled atmospheres at temperatures up to 1400 deg. C, where the SiC-fibres were prevented from losing their original properties. The matrix-material samples were characterised for their phase compositions. The SiC-fibre preform was infiltrated with the matrix material by using electrophoretic deposition. A stable and well-dispersed aqueous suspension enabled the efficient infiltration and preparation of a SiC{sub f}/SiC composite with a relatively high density. The simple and rapid SITE processing technique appears to offer a viable, low-cost alternative to the methods presently used to produce low-activation SiC{sub f}/SiC composites.

  14. Facile Preparation of Highly Conductive Metal Oxides by Self-Combustion for Solution-Processed Thermoelectric Generators.

    Science.gov (United States)

    Kang, Young Hun; Jang, Kwang-Suk; Lee, Changjin; Cho, Song Yun

    2016-03-01

    Highly conductive indium zinc oxide (IZO) thin films were successfully fabricated via a self-combustion reaction for application in solution-processed thermoelectric devices. Self-combustion efficiently facilitates the conversion of soluble precursors into metal oxides by lowering the required annealing temperature of oxide films, which leads to considerable enhancement of the electrical conductivity of IZO thin films. Such enhanced electrical conductivity induced by exothermic heat from a combustion reaction consequently yields high performance IZO thermoelectric films. In addition, the effect of the composition ratio of In to Zn precursors on the electrical and thermoelectric properties of the IZO thin films was investigated. IZO thin films with a composition ratio of In:Zn = 6:2 at the low annealing temperature of 350 °C showed an enhanced electrical conductivity, Seebeck coefficient, and power factor of 327 S cm(-1), 50.6 μV K(-1), and 83.8 μW m(-1) K(-2), respectively. Moreover, the IZO thin film prepared at an even lower temperature of 300 °C retained a large power factor of 78.7 μW m(-1) K(-2) with an electrical conductivity of 168 S cm(-1). Using the combustive IZO precursor, a thermoelectric generator consisting of 15 legs was fabricated by a printing process. The thermoelectric array generated a thermoelectric voltage of 4.95 mV at a low temperature difference (5 °C). We suggest that the highly conductive IZO thin films by self-combustion may be utilized for fabricating n-type flexible printed thermoelectric devices.

  15. Preparation of (Bi,Pb)2Sr2Ca2Cu3Ox precursor powders by a modified polyethylene glycol based sol-gel process

    DEFF Research Database (Denmark)

    Grivel, Jean-Claude; Andersen, N.H.

    2002-01-01

    A modified sol-gel process based on polyethylene glycol has been developed for preparing (Bi,Pb)(2)Sr2Ca2Cu3Ox precursor powders in view of Ag-sheeted tape manufacture. A careful control of the pH and concentration temperature yields an amorphous gel, which can be converted to a fine and extremely...... reactive powder. The reactions taking place during the process were studied. Various calcination conditions were used in order to obtain precursor powders having different characteristics (grain size distribution. phase assembly). The influence of precursor preparation parameters on the formation...

  16. Eco-friendly microwave-assisted protocol to prepare hyaluronan-fatty acid conjugates and to induce their self-assembly process.

    Science.gov (United States)

    Calce, Enrica; Mercurio, Flavia Anna; Leone, Marilisa; Saviano, Michele; De Luca, Stefania

    2016-06-05

    An environmentally sustainable and energy-efficient synthetic process has been developed to prepare hyaluronan-based nano-sized material. It consists in a microwave-promoted acylation of the hydroxyl function of the polysaccharide with natural fatty acids, performed under solvent-free conditions. The efficient interaction of the solid reagents with the MW radiation accounts for the obtained high yielded products. The self-assembly process of the obtained compounds very fast occurred in an aqueous medium under MW-radiation, thus allowing the development of a green protocol for the nano-particles preparation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Cytologic assessment of dynamics of reparative processes in the experimental conditionally aseptic wound under the action of complex preparation based on chitosan and metal nanoparticles

    Directory of Open Access Journals (Sweden)

    Konyuchenko Е.А.. Zhandarova L.F.

    2013-12-01

    Full Text Available Objective: assessment of dynamics of reparative processes with the help of cytological examination of the preparations obtained from a conditionally aseptic wound under the action of a complex preparation based on biopolymer chitosan and metal nanoparticles. Material and Methods. A conditionally aseptic wound was simulated in 40 white outbred rats. In comparison and experimental groups cytologic assessment of dynamics of reparative processes was carried out. A number of neutrophilic leukocytes and fibroblastic row perl 00 cells in the preparations is recorded on the 3rd, 5th, 7th, 10th, 14th day from the moment of formation of the wound with the use of the immersion objective. Results. It is established, that in the comparison group the cytologic pattern of impression smear was characterized by decrease in neutrophilic leukocytes and increase in fibroblastic row cells by the 14th day from the moment of formation of the wound. In the experimental group (the use of a complex preparation more intensive reduction of neutrophilic leukocytes and a significant increase in fibroblastic row cells by the 10th day and a complete healing by the 14th day from the moment of formation of the wound has been determined. Conclusion. When treated by a complex preparation based of biopolymer chitosan and metal nanoparticles earlier occurrence of fibroblastic row cells in preparations and a significant decrease in quantity of neutrophilic leukocytes have been observed.

  18. Process to prepare stable trifluorostyrene containing compounds grafted to base polymers using a solvent/water mixture

    Science.gov (United States)

    Roelofs, Mark Gerrit; Yang, Zhen-Yu; Han, Amy Qi

    2010-06-15

    A fluorinated ion exchange polymer is prepared by grafting at least one grafting monomer derived from trifluorostyrene on to at least one base polymer in a organic solvent/water mixture. These ion exchange polymers are useful in preparing catalyst coated membranes and membrane electrode assemblies used in fuel cells.

  19. Thermal stability of nanostructured titania and titania-ceria ceramic powders prepared by the sol-gel process

    NARCIS (Netherlands)

    Koebrugge, G.W.; Winnubst, A.J.A.; Burggraaf, A.J.

    1993-01-01

    The preparation and characterisation of nanometre TiO2 powder materials, prepared by the sol-gel method, are described. Controlled hydrolysis of a titanium-2-methyl-2-butoxide precursor was applied to obtain alcosols with particles (in alcohol) smaller than 5 nm. Powders obtained from this sol were

  20. Comparison of GERG-2008 and simpler EoS models in calculation of phase equilibrium and physical properties of natural gas related systems

    DEFF Research Database (Denmark)

    Varzandeh, Farhad; Stenby, Erling Halfdan; Yan, Wei

    2017-01-01

    Accurate description of thermodynamic properties of natural gas systems is of great significance in the oil and gas industry. For this application, non-cubic equations of state (EoSs) are advantageous due to their better density and compressibility description. Among the non-cubic models, GERG-2008......S is another model that despite its empirical nature, provides accurate density description even around the critical point. It is much simpler than GERG-2008 and easier to handle and generalize to reservoir oil fluids. This study presents a comprehensive comparison between GERG-2008 and other cubic (SRK and PR......) and noncubic EoSs (Soave-BWR and PC-SAFT) with a focus on Soave-BWR in description of pure components density and compressibility in a wide temperature and pressure range, calculation of binary Vapor- Liquid-Equilibria (VLE) and density, prediction of multicomponent phase envelopes and gas compressibility...

  1. Galaxies appear simpler than expected

    CERN Document Server

    Disney, M J; Garcia-Appadoo, D A; West, A A; Dalcanton, J J; Cortese, L

    2008-01-01

    Galaxies are complex systems the evolution of which apparently results from the interplay of dynamics, star formation, chemical enrichment, and feedback from supernova explosions and supermassive black holes. The hierarchical theory of galaxy formation holds that galaxies are assembled from smaller pieces, through numerous mergers of cold dark matter. The properties of an individual galaxy should be controlled by six independent parameters including mass, angular-momentum, baryon-fraction, age and size, as well as by the accidents of its recent haphazard merger history. Here we report that a sample of galaxies that were first detected through their neutral hydrogen radio-frequency emission, and are thus free of optical selection effects, shows five independent correlations among six independent observables, despite having a wide range of properties. This implies that the structure of these galaxies must be controlled by a single parameter, although we cannot identify this parameter from our dataset. Such a de...

  2. Chemical composition of protein concentrate prepared from Yellowfin tuna Thunnus albacares roe by cook-dried process

    Directory of Open Access Journals (Sweden)

    Hyun Ji Lee

    2016-05-01

    Full Text Available Abstract Roe is the term used to describe fish eggs (oocytes gathered in skeins and is one of the most valuable food products from fishery sources. Thus, means of processing are required to convert the underutilized yellowfin tuna roes (YTR into more marketable and acceptable forms as protein concentrate. Roe protein concentrates (RPCs were prepared by cooking condition (boil-dried concentrate, BDC and steam-dried concentrate, SDC, respectively and un-cooking condition (freeze-dried concentrate, FDC from yellowfin tuna roe. The yield of RPCs was in the range from 22.2 to 25.3 g/100 g of roe. RPCs contained protein (72.3–77.3 %, moisture (4.3–5.6 %, lipid (10.6–11.3 % and ash (4.3–5.7 % as the major constituents. The prominent amino acids of RPCs were aspartic acid, 8.7–9.2, glutamic acid, 13.1–13.2, and leucine, 8.5–8.6 g/100 g of protein. Major differences were not observed in each of the amino acid. K, S, Na, and P as minerals were the major elements in RPCs. No difference noted in sodium dodecyl sulfate polyacrylamide gel electrophoresis protein band (15–100 K possibly representing partial hydrolysis of myosin. Therefore, RPCs from YTR could be use potential protein ingredient for human food and animal feeds.

  3. 调理鸭舌加工工艺%Research on Processing Technology of Prepared Duck Tongue

    Institute of Scientific and Technical Information of China (English)

    王毅明; 张慜; 王拥军; 徐丰氏

    2011-01-01

    The aim of this manuscript is develop a production process of prepared duck tongue with high-chewing. For this, the infiltration of precipitation reagent combined with vacuum microwave drying was explored to improve product quality. Compared with the product by hot air drying, the product characteristics have been effectively improved in the shape and color exhibited improvement. The optimum solution composition is lactose 5 g/l00m, maltose 1 g/l00m, maltodextrin 1 g/l00m and sodium lactate 3 g/l00m was 5, 1, 1, 3 g/dL solution, the ratio of solid to liquid is 1 g : 15 mL, impregnated time lh, vacuum microwave drying, Those optimum conditions efficiently improve the product quality and extend shelf life.%作者研究了咀嚼性良好的半干调理鸭舌的生产工艺基本流程,通过降水活试剂渗透联合真空微波干燥提高产品品质,与热风干燥产品相比,产品形状、色泽得到有效改善.结果表明:经质量浓度为5、1、1、3 g/dL的乳糖、麦芽糖、麦芽糊精及乳酸钠混合液(料液质量体积比1g∶15mL)浸渍1h及经真空微波干燥处理后,可有效地改善产品品质并延长产品货架期.

  4. [Study on the preparation and properties of novel silica microporous antireflective coating by sol-gel process].

    Science.gov (United States)

    Shang, Meng-Ying; Cao, Lin-Hong; Liu, Miao; Luo, Xuan; Ren, Hong-Bo; Ye, Xin; Tang, Yong-Jian; Jiang, Xiao-Dong

    2013-04-01

    Silica sol was prepared by acid catalyzed sol-gel process using tetraethylorthosilicate (TEOS) as precursor and dimethyldietoxysilane (DDS) as pore-forming agent. A novel kind of monolayer microporous silica anti-reflective (AR) coating was obtained on K9 glass substrate by dip-coating technique and then heat treated at 500 degrees C. The effects of different DDS/TEOS molar ratios on refractive index, transmittance and hardness were investigated. A positive correlation was found between the transmittance and the DDS/TEOS molar ratio due to the increasing porosity. The maximum transmittance can reach 99.7% with the molar ratio of DDS/TEOS rising to 1 : 1. Meanwhile, the refractive index was found quite close to the ideal value 1.22. Nevertheless, higher molar ratio will lead to a bad film-forming property. On the other hand, the hardness of the coatings decreased with the DDS increasing but still remained more than 2 h when the transmittance reached highest. Besides, these coatings exhibit a well abrasion-resistance and excellent adhesivity. The maximum transmittance was only dropped by 0.071% and 0.112% after abrasion for 500 and 1 000 times respectively. Accelerated corrosion tests indicated that the transmittance of traditional coatings rapidly fell down to the substrate level (-92%) after immersion for 5 min, while the transmittance of our novel coating almost linearly decreased and was kept 93.2% after 56 min. In other words, the environment-resistance of our novel silica AR coating is ten times higher than that of traditional ones. The promotions of the coating performances benefit from its micropore structure (-0. 4 nm) with which water molecule can be effectively prevented. With its high transmittance, good mechanical properties and high environment-resistance, this kind of novel coating has a potential application in the field of solar glass modification to improve its anti-reflective properties.

  5. Dynamics of volume of competition practice and facilities of training of jumpers in length and triple in the process of long-term preparation

    Directory of Open Access Journals (Sweden)

    Sovenko S.P.

    2012-12-01

    Full Text Available Analysed and systematized information in relation to the volume of competition practice and facilities of different primary orientation of jumpers in length and triple in the process of long-term preparation. The expert questioning is conducted 16 trainers. The documents of planning of training process are analysed, the analysis of diaries of sportsmen is carried out (n=22. The volume of competition practice of sportsmen and facilities of training of different primary orientation is certain. The results of analysis in relation to the construction of training process are reflected by the leading trainers of Ukraine on track-and-field. An approach classification of facilities of training taking into account the specific of training process of sportsmen is presented. It is set that the volume of facilities of general preparation is most on the initial stages of long-term perfection, then stabilized on the stages specialized base and preparations to higher achievements and a few diminishes on maximal implementation of individual possibilities and maintainance of higher sporting trade phases. It is related to diminishing of duration of the general preparatory stages of annual preparation.

  6. Original research paper. A superior preparation method for daidzein-hydroxypropyl-β-cyclodextrin complexes with improved solubility and dissolution: Supercritical fluid process

    Directory of Open Access Journals (Sweden)

    Pan Hao

    2017-03-01

    Full Text Available Advantages of the supercritical fluid (SCF process compared to the conventional solution stirring method (CSSM in the preparation of daidzein-hydroxypropyl-β-cyclodextrin (HPβCD complexes were investigated. Formation of daidzein/ HPβCD inclusion complexes was confirmed by Fourier transformed-infrared spectroscopy (FTIR, differential scanning calorimetry (DSC, X-ray diffraction (XRD and scanning electron microscopy (SEM. Particle size, inclusion yield, drug solubility and dissolution of daidzein/HPβCD complexes were evaluated. Compared to CSSM, the SCF process resulted in higher inclusion yield and higher solubility. Also, extended dissolution of daidzein from the SCF processed HPβCD inclusion complexes was observed, with only 22.94 % released in 45 min, compared to its rapid release from those prepared by CSSM, with 98.25 % drug release in 15 min. This extended release of daidzein from SCF prepared inclusion complexes was necessary to avoid drug precipitation and improve drug solubilisation in the gastrointestinal tract. The results showed that the SCF process is a superior preparation method for daidzein-hydroxypropyl-β-cyclodextrin complexes.

  7. INCREASING OF ECOLOGICAL SAFETY OF THE PROCESSES OF SILUMINS REFINING DUE TO APPLICATION OF LOW-TOXIC FLUX METALS AND PREPARATIONS

    Directory of Open Access Journals (Sweden)

    G. A. Rumjantseva

    2010-01-01

    Full Text Available It is shown that the received complex of mechanical and technological characteristics of alloy AK9 after processing of melt with investigated fluxes and preparations can be recommer ded for use in plant conditions that will enable the increase of ecological safety of color-founding production.

  8. Effect of Additives on Characterization and Photocatalytic Activity of Tio/ZnO Nanocomposite Prepared via Sol-Gel Process

    OpenAIRE

    Shahram Moradi; Parviz Aberoomand Azar; Sanaz Raeis Farshid; Saeed Abedini Khorrami; Mohammad Hadi Givianrad

    2012-01-01

    TiO2/ZnO nanocomposites were prepared by the sol-gel method with and without addatives such as carboxy methyl cellulose (CMC), poly(ethylene glycol) (PEG), polyvinylpyrrolidon, (PVP), and hydroxylpropylcellulose (HPC). The characteristics of the prepared TiO2/ZnO nanocomposites were identified by IR spectra, X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS) methods. The additives have a significant effect on the particle size distribut...

  9. Solid-state flurbiprofen and methyl-β-cyclodextrin inclusion complexes prepared using a single-step, organic solvent-free supercritical fluid process.

    Science.gov (United States)

    Rudrangi, Shashi Ravi Suman; Kaialy, Waseem; Ghori, Muhammad U; Trivedi, Vivek; Snowden, Martin J; Alexander, Bruce David

    2016-07-01

    The aim of this study was to enhance the apparent solubility and dissolution properties of flurbiprofen through inclusion complexation with cyclodextrins. Especially, the efficacy of supercritical fluid technology as a preparative technique for the preparation of flurbiprofen-methyl-β-cyclodextrin inclusion complexes was evaluated. The complexes were prepared by supercritical carbon dioxide processing and were evaluated by solubility, differential scanning calorimetry, X-ray powder diffraction, scanning electron microscopy, practical yield, drug content estimation and in vitro dissolution studies. Computational molecular docking studies were conducted to study the possibility of molecular arrangement of inclusion complexes between flurbiprofen and methyl-β-cyclodextrin. The studies support the formation of stable molecular inclusion complexes between the drug and cyclodextrin in a 1:1 stoichiometry. In vitro dissolution studies showed that the dissolution properties of flurbiprofen were significantly enhanced by the binary mixtures prepared by supercritical carbon dioxide processing. The amount of flurbiprofen dissolved into solution alone was very low with 1.11±0.09% dissolving at the end of 60min, while the binary mixtures processed by supercritical carbon dioxide at 45°C and 200bar released 99.39±2.34% of the drug at the end of 30min. All the binary mixtures processed by supercritical carbon dioxide at 45°C exhibited a drug release of more than 80% within the first 10min irrespective of the pressure employed. The study demonstrated the single step, organic solvent-free supercritical carbon dioxide process as a promising approach for the preparation of inclusion complexes between flurbiprofen and methyl-β-cyclodextrin in solid-state.

  10. High-throughput analysis for preparation, processing and analysis of TiO{sub 2} coatings on steel by chemical solution deposition

    Energy Technology Data Exchange (ETDEWEB)

    Cuadrado Gil, Marcos, E-mail: Marcos.cuadradogil@ugent.be [SCRIPTS - Department of Inorganic and Physical Chemistry, Ghent University, Krijgslaan 281 (S3) (Belgium); Van Driessche, Isabel, E-mail: Isabel.VanDriessche@ugent.be [SCRIPTS - Department of Inorganic and Physical Chemistry, Ghent University, Krijgslaan 281 (S3) (Belgium); Van Gils, Sake, E-mail: Sake.Vangils@arcelormittal.com [OCAS - ArcelorMittal Gent R and D Centre, Pres. J.F. Kennedylaan 3, Zelzate B-9060 (Belgium); Lommens, Petra, E-mail: Petra.Lommens@ugent.be [SCRIPTS - Department of Inorganic and Physical Chemistry, Ghent University, Krijgslaan 281 (S3) (Belgium); Castelein, Pieter, E-mail: Pieter.Castelein@flamac.be [Flamac - A Division of SIM, Technologiepark 903, Zwijnaarde 9052 (Belgium); De Buysser, Klaartje, E-mail: Klaartje.DeBuysser@ugent.be [SCRIPTS - Department of Inorganic and Physical Chemistry, Ghent University, Krijgslaan 281 (S3) (Belgium)

    2012-11-05

    Highlights: Black-Right-Pointing-Pointer High-throughput preparation of TiO{sub 2} aqueous precursors. Black-Right-Pointing-Pointer Analysis of stability and surface tension. Black-Right-Pointing-Pointer Deposition of TiO{sub 2} coatings. - Abstract: A high-throughput preparation, processing and analysis of titania coatings prepared by chemical solution deposition from water-based precursors at low temperature ( Almost-Equal-To 250 Degree-Sign C) on two different types of steel substrates (Aluzinc Registered-Sign and bright annealed) is presented. The use of the high-throughput equipment allows fast preparation of multiple samples saving time, energy and material; and helps to test the scalability of the process. The process itself includes the use of IR curing for aqueous ceramic precursors and possibilities of using UV irradiation before the final sintering step. The IR curing method permits a much faster curing step compared to normal high temperature treatments in traditional convection devices (i.e., tube furnaces). The formulations, also prepared by high-throughput equipment, are found to be stable in the operational pH range of the substrates (6.5-8.5). Titanium alkoxides itself lack stability in pure water-based environments, but the presence of the different organic complexing agents prevents it from hydrolysis and precipitation reactions. The wetting interaction between the substrates and the various formulations is studied by the determination of the surface free energy of the substrates and the polar and dispersive components of the surface tension of the solutions. The mild temperature program used for preparation of the coatings however does not lead to the formation of pure crystalline material, necessary for the desired photocatalytic and super-hydrophilic behavior of these coatings. Nevertheless, some activity can be reported for these amorphous coatings by monitoring the discoloration of methylene blue in water under UV irradiation.

  11. Reflections on the process of selecting and preparing teams: the case of the brazilian youth masculine volleyball team

    Directory of Open Access Journals (Sweden)

    Viktor Shigunov

    2004-06-01

    Full Text Available This research was carried out with the aim to analyze the methodological strategy adopted by the coach of the Brazilian youth man volleyball team during training sessions in the preparation period. As a data gathering method, 45 videos were taken during sessions, 28 in Belo Horizonte and 17 in Poços de Caldas. A semi-structured interview was also held with the coach and the coaching staff . The results of the research indicated that the coach’s pedagogical practice was strongly influenced by technical, developmental and systemic methodological conceptions. This practice was developed through a combination of different methodologies, such as analytic, synthetic, structuralist, dynamic and progressive. The relationship between the coaching staff and the athletes was harmonious and respectful. It was shown that, besides to anthropometric, conditioning, technical-coordinating, tactical-cognitive and psychological factors, the twelve athletes who represented Brazil in the World Youth Championshipwere also chosen for other qualities. Among the qualities to be mentioned are the capacity for leadership, group cohesion, courage and determination . The research pointed out that the preparation process of the Brazilian team was carried out with great competence, through a correct division of training time and a careful selection of the athletes, following international standard criteria such as height, strength and individual technical skills. RESUMO Esta pesquisa foi realizada com o propósito de analisar a estratégia metodológica adotada pelo técnico da seleção brasileira masculina de voleibol infanto-juvenil nos treinamentos no período preparatório da equipe. Como instrumento de coleta de dados, foram realizadas filmagens em vídeo de 45 sessões de treinamentos, sendo 28 em Belo horizonte e 17 em Poços de Caldas. Também foi realizada uma entrevista semi-estruturada com o treinador da seleção brasileira e a sua comissão técnica. Os

  12. Novel TiC/Ti Open Cellular Foams Prepared by a Modified Sponge-coating Method Using High Frequency Induction Heating Process

    Institute of Scientific and Technical Information of China (English)

    Yong Gao; Xingxiang Xu; Zhenming Yang; Junqi Zhang; Chunhai Jiang; Jinsong Zhang

    2013-01-01

    A new kind of open cellular foam material with three dimensionally interconnected TiC/Ti struts was prepared by a two-step sponge-coating and high frequency induction heating process.The microstructure,composition and compression strength of the prepared TiC/Ti foam materials were characterized.It was confirmed that the incorporation of Ti into TiC resulted in an inter-bonded Ti-TiC-Ti layered structure in the struts,which enhanced the plasticity of the composite foam materials.

  13. LiNi0.5Mn1.5O4-based composite electrodes with improved properties prepared by a slurry spray deposition process

    Science.gov (United States)

    Yu, Ran; Sun, Yi; Zou, Bang-Kun; Deng, Miao-Miao; Xie, Jing-Ying; Chen, Chun-Hua

    2017-02-01

    A slurry spray deposition (SSD) process is utilized to prepare a LiNi0.5Mn1.5O4-based composite electrode supported on an aluminum foil. The spray deposition process is performed at room temperature through the atomization and deposition of the composite electrode slurry. A comparative LiNi0.5Mn1.5O4-based composite electrode is also prepared by the traditional blade coating method. The surface morphology and elements mapping of the electrodes are measured by scanning electron microscopy and energy-dispersive X-ray spectroscopy, respectively. The adhesion between the composite electrode layers and the aluminum foil is also tested. A parallel evaluation on the mechanical and electrochemical performances of the two kinds of electrodes is conducted. The SSD electrode exhibits improved adhesion, cycling stability and rate capability. Therefore, the SSD process is an effective way to fabricate advanced electrodes for high performance lithium ion cells.

  14. Electrochemical properties of MnS-C and MnO-C composite powders prepared via spray drying process

    Science.gov (United States)

    Jeon, Kyung Min; Cho, Jung Sang; Kang, Yun Chan

    2015-11-01

    Spherical micron-sized MnS-C and MnO-C composite powders are successfully prepared by post-treating the spray-dried precursor powders. Dextrin, which is used as the carbon source material, plays a key role in the preparation of the composite powders with regular morphologies; the bare MnS and MnO powders prepared from the spray solution without dextrin have irregular morphologies. The MnS-C composite powders prepared from the spray solution containing 17 g L-1 of dextrin have mixed crystal structures of α- and γ-MnS phases. These powders exhibit superior electrochemical properties compared with those of their MnS and MnO-C counterparts. For example, at a current density of 0.5 A g-1, the MnO-C powders have a 100th-cycle discharge capacity of 321 mA h g-1; the corresponding discharge capacities of the MnS powders prepared from spray solutions containing 0, 17, and 50 g L-1 of dextrin are 501, 786, and 636 mA h g-1, respectively.

  15. Preparation and characterization of porous bioceramic layers on pure titanium surfaces obtained by micro-arc oxidation process

    Science.gov (United States)

    Chien, Chi-Sheng; Hung, Yu-Chien; Hong, Ting-Fu; Wu, Chung-Chun; Kuo, Tsung-Yuan; Lee, Tzer-Min; Liao, Tze-Yuan; Lin, Huan-Chang; Chuang, Cheng-Hsin

    2017-03-01

    Fluorapatite (FA) has better chemical and thermal stability than hydroxyapatite (HA), and has thus attracted significant interest for biomaterial applications in recent years. In this study, porous bioceramic layers were prepared on pure titanium surfaces using a micro-arc oxidation (MAO) technique with an applied voltage of 450 V and an oxidation time of 5 min. The MAO process was performed using three different electrolyte solutions containing calcium fluoride (CaF2), calcium acetate monohydrate (Ca(CH3COO)2·H2O), and sodium phosphate monobasic dihydrate (NaH2PO4·2H2O) mixed in ratios of 0:2:1, 1:1:1, and 2:0:1, respectively. The surface morphology, composition, micro-hardness, porosity, and biological properties of the various MAO coatings were examined and compared. The results showed that as the CaF2/Ca(CH3COO)2·H2O ratio increased, the elemental composition of the MAO coating transformed from HA, A-TiO2 (Anatase) and R-TiO2 (Rutile); to A-TiO2, R-TiO2, and a small amount of HA; and finally A-TiO2, R-TiO2, CaF2, TiP2O5, and FA. The change in elemental composition was accompanied by a higher micro-hardness and a lower porosity. The coatings exhibited a similar in vitro bioactivity performance during immersion in simulated body fluid for 7-28 days. Furthermore, for in initial in vitro biocompatibility tests performed for 24 h using Dulbecco's Modified Eagle Medium (DMEM) supplement containing 10%Fetal bovine serum, the attachment and spreading of osteoblast-like osteosarcoma MG63 cells were found to increase slightly with an increasing CaF2/Ca(CH3COO)2·H2O ratio. In general, the results presented in this study show that all three MAO coatings possess a certain degree of in vitro bioactivity and biocompatibility.

  16. Physical properties of sodium silicate based silica aerogels prepared by single step sol-gel process dried at ambient pressure

    Energy Technology Data Exchange (ETDEWEB)

    Gurav, Jyoti L. [Air Glass Laboratory, Department of Physics, Shivaji University, Kolhapur 416004, Maharashtra (India); Rao, A. Venkateswara [Air Glass Laboratory, Department of Physics, Shivaji University, Kolhapur 416004, Maharashtra (India)], E-mail: raouniv@yahoo.com; Rao, A. Parvathy; Nadargi, D.Y.; Bhagat, S.D. [Air Glass Laboratory, Department of Physics, Shivaji University, Kolhapur 416004, Maharashtra (India)

    2009-05-12

    The experimental results on physical properties of water glass (sodium silicate) based silica aerogels prepared by single step sol-gel process, dried at atmospheric pressure are reported. The hydrolysis and condensation reactions of the sodium silicate precursor proceeded with tartaric acid as a catalyst. The hydrogel was vapour passed in order to remove sodium salt from the gel network. Solvent exchange was carried out using methanol and hexane as a solvents. Finally, surface chemical modification of the gel was done using trimethylchlorosilane (TMCS) followed by ambient pressure drying of the gel up to the temperature 200 deg. C. To get good quality aerogels various sol-gel parameters such as water vapour passing period varied from 0.5 to 2 h, gel aging from 1 to 4 h, Na{sub 2}SiO{sub 3}/H{sub 2}O molar ratio from 3 x 10{sup -3} to 1.5 x 10{sup -2}, tartaric acid/Na{sub 2}SiO{sub 3} molar ratio from 0.3 to 1.9 and TMCS/Na{sub 2}SiO{sub 3} molar ratio from 4.8 to 12. The aerogels were characterized by percentage of volume shrinkage, bulk density, porosity and hydrophobicity. The hydrophobicity of the aerogel was confirmed by Fourier Transform Infrared (FTIR) Spectroscopy and contact angle measurements. Microstructural studies have been carried out by Scanning Electron Microscopy (SEM) and nitrogen adsorption BET analysis. From the TGA-DTA studies of the aerogels, it was found that the aerogels were thermally stable up to 470 {sup o}C. Low density ({approx}0.066 g/cm{sup 3}), high hydrophobicity ({approx}145 deg.), high porosity ({approx}97 %), high pore volume, surface area of 510 m{sup 2}/g aerogels have been obtained for Na{sub 2}SiO{sub 3}:H{sub 2}O:tartaric acid (C{sub 4}H{sub 6}O{sub 6}):TMCS molar ratio at 1:166.6:2.5:12 respectively with half an hour water vapour passing.

  17. [Study on processing adjuvant medicines in Lei Gong's treatise on preparation and broiling of materia medica (Leigong Paozhi Lun)].

    Science.gov (United States)

    Zhang, Wei; Zhang, Ruixian

    2010-09-01

    There were 268 kinds of medicines recorded in the book of Lei Gong's Treatise on preparation and broiling of materia medica (Leigong Paozhi Lun). Among these medicines, 178 medicines were prepared with adjuvant medicines, including general and special compatible adjuvant medicines. These adjuvant medicines used in this book can be explained by the theory of "seven-relation compatibility". The author tried to explain the usage and their compatibility of these adjuvant medicines and put forward that attention should be paid to the changes in functions of medicines and the influences of society should be paid attention.

  18. Fieldcrest Cannon, Inc. Advanced Technical Preparation. Statistical Process Control (SPC). Safety Section: Modules 1-3. Instructor Book.

    Science.gov (United States)

    Averitt, Sallie D.

    These three modules, which were developed for use by instructors in a manufacturing firm's advanced technical preparation program, contain the materials required to present the safety section of the plant's adult-oriented, job-specific competency-based training program. The 3 modules contain 12 lessons on the following topics: lockout/tagout…

  19. Fieldcrest Cannon, Inc. Advanced Technical Preparation. Statistical Process Control (SPC). Safety Section: Modules 1-3. Instructor Book.

    Science.gov (United States)

    Averitt, Sallie D.

    These three modules, which were developed for use by instructors in a manufacturing firm's advanced technical preparation program, contain the materials required to present the safety section of the plant's adult-oriented, job-specific competency-based training program. The 3 modules contain 12 lessons on the following topics: lockout/tagout…

  20. Compression and evaluation of extended release matrix pellets prepared by the extrusion/spheronization process into disintegrating tablets

    Directory of Open Access Journals (Sweden)

    Raveendra Pai

    2012-03-01

    Full Text Available In this study, a novel approach for compression of matrix pellets into disintegrating tablets has been studied in an attempt to overcome the issues pertaining to rupture of polymer coat during compression of reservoir-type pellets. Extended release matrix pellets were prepared by the extrusion/spheronization technique using commercially available aqueous dispersions of ethyl cellulose, acrylic polymers and sodium alginate at 10%, 20% and 30%w/w levels. Sertraline hydrochloride was used as the model drug and an in vitro release profile of 12 h was targeted. Tablets containing matrix pellets were prepared by the direct compression process. Acceptance Value, a pharmacopeial test, was applied to study the uniformity of drug distribution. Effect of compression force (2-6 kN, extrusion screen aperture size, diluent blend composition and pellet percentage on drug release and acceptance value were studied. As polymer is uniformly distributed within each pellet, the drug release pattern from uncompressed pellets was comparable to compressed tablets. Surface morphological changes due to calcium chloride treatment were observed using Scanning electron microscopy. The pellet segregated from the surface of the tablet was found to be flattened in the direction of applied compression force with minor deformities. In conclusion, matrix pellets can constitute an alternative approach to reservoir-type pellets in obtaining disintegrating tablets for extended delivery of drugs.Nesse trabalho, estudou-se nova abordagem para a compressão de matrizes de péletes em comprimidos desintegrantes, com o intuito de resolver os problemas relativos à ruptura do polímero de revestimento durante a compressão dos péletes do tipo reservatório. Matrizes de péletes de liberação estendida foram preparadas pela técnica de extrusão/esferonização, utilizando dispersões aquosas comercialmente disponíveis de etil celulose, polímeros acrílicos e alginato de sódio a 10