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25,846 full-text articles. Page 677 of 696.

Testing Lyoequivalency For Three Commercially Sustainedrelease Tablets Containing Diltiazem Hydrochloride, Philadelphia University 2010 Philadelphia University

Testing Lyoequivalency For Three Commercially Sustainedrelease Tablets Containing Diltiazem Hydrochloride, Philadelphia University

Philadelphia University, Jordan

No abstract provided.


The Novel And The Experimentation, Philadelphia University 2010 Philadelphia University

The Novel And The Experimentation, Philadelphia University

Philadelphia University, Jordan

No abstract provided.


Neural-Network-Based Fuzzy Identifier: Design And Evaluation, Philadelphia University 2010 Philadelphia University

Neural-Network-Based Fuzzy Identifier: Design And Evaluation, Philadelphia University

Philadelphia University, Jordan

No abstract provided.


Using Database Marketing To Enhance Direct Marketing Alternatives In Jordanian Industrial Shareholders Corporations, Philadelphia University 2010 Philadelphia University

Using Database Marketing To Enhance Direct Marketing Alternatives In Jordanian Industrial Shareholders Corporations, Philadelphia University

Philadelphia University, Jordan

No abstract provided.


Enantioselective Synthesis Of Bicarbocyclic Structures With An All-Carbon Quaternary Stereocenter Through Sequential Cross Metathesis And Intramolecular Rauhut-Currier Reaction, Yuan Qiao, Sanjeev Kumar, William Paul Malachowski 2010 Bryn Mawr College

Enantioselective Synthesis Of Bicarbocyclic Structures With An All-Carbon Quaternary Stereocenter Through Sequential Cross Metathesis And Intramolecular Rauhut-Currier Reaction, Yuan Qiao, Sanjeev Kumar, William Paul Malachowski

Chemistry Faculty Research and Scholarship

A new extension of the Birch-Cope sequence is described which allows the efficient enantioselective construction of highly functionalized, fused bicarbocyclic structures with an all-carbon quaternary stereo-center in two steps. The two-step sequence includes a cross metathesis between a terminal alkene and a polarized alkene followed by an intramolecular Rauhut-Currier reaction with a trialkylphosphine catalyst.


Noninnocent Dithiolene Ligands: A New Oxomolybdenum Complex Possessing A Donor-Acceptor Dithiolene Ligand, Kelly G. Matz, Regina P. Mtei, Belinda Leung, Sharon J. Nieter Burgmayer, Martin L. Kirk 2010 Bryn Mawr College

Noninnocent Dithiolene Ligands: A New Oxomolybdenum Complex Possessing A Donor-Acceptor Dithiolene Ligand, Kelly G. Matz, Regina P. Mtei, Belinda Leung, Sharon J. Nieter Burgmayer, Martin L. Kirk

Chemistry Faculty Research and Scholarship

No abstract provided.


Trace Gas And Particle Emissions From Domestic And Industrial Biofuel Use And Garbage Burning In Central Mexico, Ted J. Christian, Robert Yokelson, B. Cardenas, L. T. Molina, G. Engling, S. C. Hsu 2010 University of Montana - Missoula

Trace Gas And Particle Emissions From Domestic And Industrial Biofuel Use And Garbage Burning In Central Mexico, Ted J. Christian, Robert Yokelson, B. Cardenas, L. T. Molina, G. Engling, S. C. Hsu

Chemistry and Biochemistry Faculty Publications

In central Mexico during the spring of 2007 we measured the initial emissions of 12 gases and the aerosol speciation for elemental and organic carbon (EC, OC), anhydrosugars, Cl(-), NO(3)(-), and 20 metals from 10 cooking fires, four garbage fires, three brick making kilns, three charcoal making kilns, and two crop residue fires. Global biofuel use has been estimated at over 2600 Tg/y. With several simple case studies we show that cooking fires can be a major, or the major, source of several gases and fine particles in developing countries. Insulated cook stoves with chimneys were earlier shown ...


Evolution Of Trace Gases And Particles Emitted By A Chaparral Fire In California, S. K. Akagi, J. S. Craven, J. W. Taylor, G. R. McMeeking, Robert J. Yokelson, I. R. Burling, S. P. Urbanski, C. E. Wold, J. H. Seinfeld, H. Coe, M. J. Alvarado, D. R. Weise 2010 University of Montana - Missoula

Evolution Of Trace Gases And Particles Emitted By A Chaparral Fire In California, S. K. Akagi, J. S. Craven, J. W. Taylor, G. R. Mcmeeking, Robert J. Yokelson, I. R. Burling, S. P. Urbanski, C. E. Wold, J. H. Seinfeld, H. Coe, M. J. Alvarado, D. R. Weise

Chemistry and Biochemistry Faculty Publications

Biomass burning (BB) is a major global source of trace gases and particles. Accurately representing the production and evolution of these emissions is an important goal for atmospheric chemical transport models. We measured a suite of gases and aerosols emitted from an 81 hectare prescribed fire in chaparral fuels on the central coast of California, US on 17 November 2009. We also measured physical and chemical changes that occurred in the isolated down-wind plume in the first similar to 4 h after emission. The measurements were carried out onboard a Twin Otter aircraft outfitted with an airborne Fourier transform infrared ...


Vcd On Common Laboratory Techniques In Analytical Chemistry And Organic Chemistry, Ricky M S Wong, Kwok Keung Shiu 2010 Hong Kong Baptist University

Vcd On Common Laboratory Techniques In Analytical Chemistry And Organic Chemistry, Ricky M S Wong, Kwok Keung Shiu

Department of Chemistry Book Chapter

The VCDs aiming to provide relevant self-learning materials for year-one Chemistry majored students to learn the basic laborator y techniques encountered in Analytical and Organic Chemistr y laboratories were produced. To enhance teaching and learning, two different presentation approaches - role-playing and experiment demonstration - were adopted in the video. The first part of the video covers basic analytical chemistry techniques such as proper chemical weighing and handling, correct use of volumetric flasks, titration with standardised NaOH and accurate burette reading. The second part involves techniques commonly employed in an Organic Chemistr y laborator y such as simple distillation, general reflux, liquid-liquid ...


Towards The Establishment Of A "First-Rate" Undergraduate Teaching Programme In Analytical Chemistry: Development Of Innovative Multimedium Software Training Package, Wing Hong Chan, Carmen W K Huie, Kwok Keung Shiu, Martin M F Choi 2010 Hong Kong Baptist University

Towards The Establishment Of A "First-Rate" Undergraduate Teaching Programme In Analytical Chemistry: Development Of Innovative Multimedium Software Training Package, Wing Hong Chan, Carmen W K Huie, Kwok Keung Shiu, Martin M F Choi

Department of Chemistry Book Chapter

To introduce more fun and incentive for undergraduate students in learning analytical chemistry, the development of innovative multimedium software package that vividly illustrated the relationship between basic scientific principles in analytical chemistry and their applications in solving real-life analytical problems relevant to Hong Kong was proposed. In this project, unique VCDs containing visual images and interesting stories were developed to allow for stepby step explanation of the analytical procedures involved in the chemical analysis of four cases, viz cadmium in oyster, nicotine in cigarettes, metals in green tea leaves and ginsenosides in American Ginseng. To tackle the analytical problems, unique ...


A Chemical Ionization Mass Spectrometer For Ambient Measurements Of Ammonia, D. R. Benson, A. Markovich, M. Al-Refai, Shan-Hu Lee 2010 Kent State University - Kent Campus

A Chemical Ionization Mass Spectrometer For Ambient Measurements Of Ammonia, D. R. Benson, A. Markovich, M. Al-Refai, Shan-Hu Lee

Biostatistics, Environmental Health, and Epidemiology Publications

his study presents a chemical ionization mass spectrometer (CIMS) for fast response, in-situ measurements of gas phase ammonia (NH3). The NH3 background level detected with the CIMS ranged between 0.3–1 ppbv, with an uncertainty of 30 pptv under optimized conditions. The instrument sensitivity varied from 4–25 Hz/pptv for >1 MHz of reagent ion signals (protonated ethanol ions), with a 30% uncertainty estimated based on variability in calibration signals. The CIMS detection limit for NH3 was ~60 pptv at a 1 min integration time (3 sigma). The CIMS time response was <30 s. This new NH3-CIMS has ...


Phytoprotective Influence Of Bacteria On Growth And Cadmium Accumulation In The Aquatic Plant Lemna Minor, Lisa M Stout, Elena N Dodova, Julian Tyson, Klaus Nusslein 2010 University of Massachusetts Amherst

Phytoprotective Influence Of Bacteria On Growth And Cadmium Accumulation In The Aquatic Plant Lemna Minor, Lisa M Stout, Elena N Dodova, Julian Tyson, Klaus Nusslein

Chemistry Department Faculty Publication Series

No abstract provided.


A New Method For The Analysis Of [Beta]2-Agonists In Human Urine By Pressure-Assisted Capillary Electrochromatography Coupled With Electrospray Ionization-Mass Spectrometry Using A Silica-Based Monolithic Column, Minghua Lu, Lan Zhang, Xin Li, Qiaomei Lu, Guonan Chen, Zongwei Cai 2010 Hong Kong Baptist University

A New Method For The Analysis Of [Beta]2-Agonists In Human Urine By Pressure-Assisted Capillary Electrochromatography Coupled With Electrospray Ionization-Mass Spectrometry Using A Silica-Based Monolithic Column, Minghua Lu, Lan Zhang, Xin Li, Qiaomei Lu, Guonan Chen, Zongwei Cai

Department of Chemistry Journal Articles

A new pressure-assisted capillary electrochromatography coupled with electrospray ionization-mass spectrometry method using a silica-based monolithic column as separation media was developed for the analysis of β2-agonists in human urine. Experimental conditions including the mobile phase, separation voltage, assisted pressure, and sheath liquid were optimized for the analysis: mobile phase composed of 82% (v/v) ACN and 18% (v/v) 20 mmol/L ammonium acetate (pH 6.0); separation voltage 25 kV; assisted pressure 2 bar; and the sheath liquid consisting of 7.5 mmol/L acetic acid in isopropanol/water 50/50% (v/v) that was delivered at a flow ...


Air-Stable Hypervalent Organobismuth(Iii) Tetrafluoroborate As Effective And Reusable Catalyst For The Allylation Of Aldehyde With Tetraallyltin, Xiaowen Zhang, Renhua Qiu, Nianyuan Tan, Shuangfeng Yin, Jun Xia, Shenglian Luo, Chak-Tong Au 2010 Hong Kong Baptist University

Air-Stable Hypervalent Organobismuth(Iii) Tetrafluoroborate As Effective And Reusable Catalyst For The Allylation Of Aldehyde With Tetraallyltin, Xiaowen Zhang, Renhua Qiu, Nianyuan Tan, Shuangfeng Yin, Jun Xia, Shenglian Luo, Chak-Tong Au

Department of Chemistry Journal Articles

Air-stable hypervalent organobismuth(III) tetrafluoroborate (C6H11N(CH2C6H4)2BiBF4) was synthesized and characterized by spectroscopic and X-ray crystallographic techniques. The compound shows good catalytic efficiency in the allylation reaction of different aldehydes with tetraallyltin in a medium of aqueous methanol, giving the corresponding homoallylic alcohols in excellent chemoselectivity and yields.


A Mini Review On Chemical Fixation Of Co2: Absorption And Catalytic Conversion Into Cyclic Carbonates, Weili Dai, Shenglian Luo, Shuangfeng Yin, Chak-Tong Au 2010 Hong Kong Baptist University

A Mini Review On Chemical Fixation Of Co2: Absorption And Catalytic Conversion Into Cyclic Carbonates, Weili Dai, Shenglian Luo, Shuangfeng Yin, Chak-Tong Au

Department of Chemistry Journal Articles

In this article, we present our research results on chemical fixation of CO2 using organobismuth compounds. We fabricated bismuth biphenoate complex, Zn-Mg-Al composite oxides, and SBA-15 or Al-SBA-15 immobilized hydroxyl ionic liquid for CO2 cycloaddition onto epoxides. The hypervalent bismuth compounds show good ability for association and dissociation with CO2. The bismuth biphenolate complexes are catalytically effective for the cycloaddition reaction. The heterogeneous catalysts, viz. Zn-Mg-Al oxides and SBA-15 or Al-SBA-15 immobilized ionic liquid, are efficient for the synthesis of cyclic carbonate from CO2 and epoxide. It is found that the presence of a trace amount of water can improve ...


Crox/Nano-Ce0.60zr0.35y0.05o2 Catalysts That Are Highly Selective For The Oxidative Dehydrogenation Of Isobutane To Isobutene, Guozhi Wang, Hongxing Dai, Lei Zhang, Jiguang Deng, Caixin Liu, Hong He, Chak-Tong Au 2010 Hong Kong Baptist University

Crox/Nano-Ce0.60zr0.35y0.05o2 Catalysts That Are Highly Selective For The Oxidative Dehydrogenation Of Isobutane To Isobutene, Guozhi Wang, Hongxing Dai, Lei Zhang, Jiguang Deng, Caixin Liu, Hong He, Chak-Tong Au

Department of Chemistry Journal Articles

Fluorite-type nanosized Ce0.60Zr0.35Y0.05O2 (nano-CZY) solid solution catalysts that are relatively uniform in particle size (4–5 nm) and y CrOx/nano-CZY (y is the weight percentage of Cr2O3 ranging from 2 to 10 wt%) catalysts were prepared by the ethylene glycol-assisted CTAB-templated co-precipitation and incipient wetness impregnation methods, respectively. The materials were characterized by a number of analytical techniques and their catalytic performance was evaluated for the oxidative dehydrogenation of isobutane. The y CrOx/nano-CZY catalysts show excellent activities, with the y = 8 wt% one performing the best (ca. 93% isobutene selectivity and ca. 10% isobutene yield ...


Proposal Narrative, Morton Sternheim, Stephan Schneider 2010 University of Massachusetts - Amherst

Proposal Narrative, Morton Sternheim, Stephan Schneider

STEM Digital

No abstract provided.


Electrochemical Sensing In Paper-Based Microfluidic Devices, Zhihong Nie, Christian A. Nijhuis, Jinlong Gong, Xin Chen, Alexander Kumachev, Andres W. Martinez, Max Narovlyansky, George M. Whitesides 2010 Harvard University

Electrochemical Sensing In Paper-Based Microfluidic Devices, Zhihong Nie, Christian A. Nijhuis, Jinlong Gong, Xin Chen, Alexander Kumachev, Andres W. Martinez, Max Narovlyansky, George M. Whitesides

Chemistry and Biochemistry

This paper describes the fabrication and the performance of microfluidic paper-based electrochemical sensing devices (we call the microfluidic paper-based electrochemical devices, μPEDs). The μPEDs comprise paper-based microfluidic channels patterned by photolithography or wax printing, and electrodes screen-printed from conducting inks (e.g., carbon or Ag/AgCl). We demonstrated that the μPEDs are capable of quantifying the concentrations of various analytes (e.g., heavy-metal ions and glucose) in aqueous solutions. This low-cost analytical device should be useful for applications in public health, environmental monitoring, and the developing world.


Programmable Diagnostic Devices Made From Paper And Tape, Andres W. Martinez, Scott T. Phillips, Zhihong Nie, Chao-Min Cheng, Emanuel Carrilho, Benjamin J. Wiley, George M. Whitesides 2010 Harvard University

Programmable Diagnostic Devices Made From Paper And Tape, Andres W. Martinez, Scott T. Phillips, Zhihong Nie, Chao-Min Cheng, Emanuel Carrilho, Benjamin J. Wiley, George M. Whitesides

Chemistry and Biochemistry

This paper describes three-dimensional microfluidic paper-based analytical devices (3-D μPADs) that can be programmed (postfabrication) by the user to generate multiple patterns of flow through them. These devices are programmed by pressing single-use ‘on’ buttons, using a stylus or a ballpoint pen. Pressing a button closes a small space (gap) between two vertically aligned microfluidic channels, and allows fluids to wick from one channel to the other. These devices are simple to fabricate, and are made entirely out of paper and double-sided adhesive tape. Programmable devices expand the capabilities of μPADs and provide a simple method for controlling the movement ...


Millimeter-Scale Contact Printing Of Aqueous Solutions Using A Stamp Made Out Of Paper And Tape, Chao-Min Cheng, Aaron D. Mazzeo, Jinlong Gong, Andres W. Martinez, Scott T. Phillips, Nina Jain, George M. Whitesides 2010 Harvard University

Millimeter-Scale Contact Printing Of Aqueous Solutions Using A Stamp Made Out Of Paper And Tape, Chao-Min Cheng, Aaron D. Mazzeo, Jinlong Gong, Andres W. Martinez, Scott T. Phillips, Nina Jain, George M. Whitesides

Chemistry and Biochemistry

This communication describes a simple method for printing aqueous solutions with millimeter-scale patterns on a variety of substrates using an easily fabricated, paper-based microfluidic device (a paper-based ―stamp‖) as a contact printing device. The device is made from inexpensive materials, and it is easily assembled by hand; this method is thus accessible to a wide range of laboratories and budgets. A single device was used to print over 2500 spots in less than three minutes at a density of 16 spots per square centimetre. This method provides a new tool to pattern biochemicals—reagents, antigens, proteins, and DNA—on planar ...


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