Structures and Synthesis of Zwitterionic Polymers
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Sodium Sulfate CAS N°: 7757-82-6
OECD SIDS SODIUM SULFATE FOREWORD INTRODUCTION Sodium sulfate CAS N°: 7757-82-6 UNEP PUBLICATIONS 1 OECD SIDS SODIUM SULFATE SIDS Initial Assessment Report For SIAM 20 Paris, France, 19 – 22 April 2005 1. Chemical Name: Sodium sulfate 2. CAS Number: 7757-82-6 3. Sponsor Country: Slovak Republic Contact Point: Centre for Chemical Substances and Preparations, Bratislava Contact Person: Peter Rusnak, Ph.D. Director Co-sponsor Country: Czech Republic Contact Point: Ministry of Environment Contact Person: Karel Bláha, Ph.D. Director Department of Environmental Risks Prague 4. Shared Partnership with: Sodium Sulfate Producers Association (SSPA)∗ and TOSOH 5. Roles/Responsibilities of the Partners: • Name of industry sponsor Sodium Sulfate Producers Association (SSPA) /consortium • Process used Documents were drafted by the consortium, then peer reviewed by sponsor countries experts 6. Sponsorship History • How was the chemical or Nominated by ICCA in the framework of the ICCA HPV category brought into the program OECD HPV Chemicals Programme? 7. Review Process Prior to Two drafts were reviewed by the Slovakian/Czech authorities; third the SIAM: draft subject to review by OECD membership 8. Quality check process: Data was reviewed against the OECD criteria as described in the SIDS manual. These criteria were used to select data for extraction into the SIDS dossier. Original data was sought wherever possible. Originally reported work was deemed reliable if sufficient information was reported (according to the manual) to judge it robust. Reviews were only judged reliable if reported 2 UNEP PUBLICATIONS OECD SIDS SODIUM SULFATE by reputable organisations/authorities or if partners had been directly involved in their production 9. -
Comment Response 7-1 7 0 Propose to Add References to AMAP Report 2012 on Effects of BC in the Arctic
Expert Review Comments on the IPCC WGI AR5 First Order Draft -- Chapter 7 Comment Chapter From From To To No Page Line Page Line Comment Response 7-1 7 0 Propose to add references to AMAP report 2012 on effects of BC in the Arctic. AMAP, 2011. The Impact of reviewer needs to be specific as to where this fits. Black Carbon on Arctic Climate (2011). Quinn et al. Arctic Monitoring and Assessment Programme (AMAP), Preference goes to peer-reviewed literature. Oslo. 72 pp. [Øyvind Christophersen, Norway] 7-2 7 0 This chapter is considerably improved from the ZOD, and I commend the authors for constructing a draft that We concur with these comments about the amounts is more balanced, better organized, covers most of the important issues, and is well written. That having been of detail in each section. We will try to address the said, there are still differences in approach and emphasis among the individual sections on clouds, aerosols, imbalances while at the same time reducing the and cloud-aerosol interactions. The chapter as a whole would benefit if these differences were reduced. The overall length as required by the TSU. clouds section, with one exception noted in a future comment, really focuses on the climatic effects of clouds and eschews detailed discussions of the cloud physics that leads to these climate effects, so much so that some of the more important science issues are ignored and others given short shrift. The aerosol section is just the opposite - it reads more like a review article in a journal than an IPCC report section, reviewing all the details of aerosol physics/chemistry, including many things that may or may not turn out to be significant in the future but which have not yet been demonstrated to be important to climate change. -
I. Gas Phase Proton Affinity of Zwitterionic Betaine N. High
I. Gas Phase Proton Affinity of Zwitterionic Betaine n. High Resolution Spectroscopy of Trapped Ions: Concept and Design Thesis by Hak-No Lee In Partial Fulfillment of the Requirements for the Degree o f Doctor of Philosophy California Institute of Technology Pasadena, California 1999 (Submitted September 30, 1998) Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Acknowledgements Much gratitude is owed to my thesis advisors, Professors Jack Beauchamp and Dan Weitekamp, for their guidance and support. I feel fortunate to have worked with advisors who value and emphasize the training of their students. I thank them for allowing me to pursue studies of my own interest, without the pressure to produce timely results. Such freedom has enabled me to obtain exposure to a wide variety of areas in physical chemistry and chemical physics: An invaluable training that would be difficult to attain after graduation. There are many people whose support and friendship enriched my years at Caltech, including fellow graduate students and the staff of the chemistry department. Special thanks go to the members of Beauchamp group, past and present: Sherrie Campbell, Elaine Marzluff, Kevin Crellin, Jim Smith, Sang Won Lee, Dmitri Kossakovski, Hyun Sik Kim, Thomas Schindler, Patrick Vogel, and Priscilla Boon. Always willing to help and answer questions, they contributed significantly to my learning and provided companionship for which I am grateful. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Abstract In an ideal experiment, the system being investigated is isolated from the environment. The only external influences allowed on the system are the parameters that the experimenter chooses to vary, in effort to study their effects on the observables. -
Recent Advances in Chiral Analysis of Proteins and Peptides
separations Review Recent Advances in Chiral Analysis of Proteins and Peptides Marine Morvan 1,2,* and Ivan Mikšík 1,2,* 1 Institute of Physiology of the Czech Academy of Sciences, Vídeˇnská 1083, 142 20 Prague, Czech Republic 2 Department of Analytical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, 532 10 Pardubice, Czech Republic * Correspondence: [email protected] (M.M.); [email protected] (I.M.) Abstract: Like many biological compounds, proteins are found primarily in their homochiral form. However, homochirality is not guaranteed throughout life. Determining their chiral proteinogenic sequence is a complex analytical challenge. This is because certain D-amino acids contained in proteins play a role in human health and disease. This is the case, for example, with D-Asp in elastin, b-amyloid and a-crystallin which, respectively, have an action on arteriosclerosis, Alzheimer’s disease and cataracts. Sequence-dependent and sequence-independent are the two strategies for detecting the presence and position of D-amino acids in proteins. These methods rely on enzymatic digestion by a site-specific enzyme and acid hydrolysis in a deuterium or tritium environment to limit the natural racemization of amino acids. In this review, chromatographic and electrophoretic techniques, such as LC, SFC, GC and CE, will be recently developed (2018–2020) for the enantioseparation of amino acids and peptides. For future work, the discovery and development of new chiral stationary phases and derivatization reagents could increase the resolution of chiral separations. Keywords: chiral separation; proteins; peptides; D-amino acids Citation: Morvan, M.; Mikšík, I. Recent Advances in Chiral Analysis of Proteins and Peptides. -
Preparation of Soil Nutrient Amendment Using White Mud Produced in Ammonia-Soda Process and Its Environmental Assessment
Preparation of soil nutrient amendment using white mud produced in ammonia-soda process and its environmental assessment SHI Lin(石 林), LUO Han-jin(罗汉金) College of Environmental Science and Engineering, South China University of Technology, Guangzhou 510006, China Received 15 July 2009; accepted 7 September 2009 Abstract: A novel method to prepare soil nutrient amendment by calcining a mixture of white mud and potassium feldspar and its for white mud to 30׃environmental assessment were investigated. Under the optimal conditions of a blending mass ratio of 70 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 2− − 23.43%, MgO 5.04%, SiO2 22.92%, SO4 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. Key words: white mud; potassium feldspar; soil nutrient amendment; environmental assessment; preparation white mud, in combination with the above-mentioned 1 Introduction factors, makes it become a serious obstruction for application in the building and cement industry. So far, Distilled waste sludge containing 50%−60% water, the common treatment of white mud is still to discard it commonly known as “white mud”, is discharged from into waterway or dispose of it in landfills. -
Beneficial Effects of Betaine: a Comprehensive Review
biology Review Beneficial Effects of Betaine: A Comprehensive Review Madan Kumar Arumugam 1,2 , Matthew C. Paal 1,2, Terrence M. Donohue Jr. 1,2,3, Murali Ganesan 1,2, Natalia A. Osna 1,2 and Kusum K. Kharbanda 1,2,3,* 1 Research Service, Veterans Affairs Nebraska-Western Iowa Health Care System, Omaha, NE 68105, USA; [email protected] (MK.A.); [email protected] (M.C.P.); [email protected] (T.M.D.J.); [email protected] (M.G.); [email protected] (N.A.O.) 2 Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA 3 Department of Biochemistry & Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA * Correspondence: [email protected]; Tel.: +1-402-995-3752; Fax: +1-402-995-4600 Simple Summary: A large number of studies report that medicinal herbs and many food ingredients protect against the development of liver disease because they possess antioxidant, anti-inflammatory, or anti-necrotic activities. This review focuses on the biological and beneficial effects of dietary betaine (trimethylglycine), a naturally occurring and crucial methyl donor, that restores methionine homeostasis in cells. We describe recent studies on betaine’s mechanism(s) of action as a therapeutic agent for improving indices of alcohol-induced and metabolic- associated liver disease. Due to its low cost, high tolerability, and efficacy, we suggest betaine as a promising therapeutic for clinical use to treat these aforementioned diseases as well as other liver-/non-liver-related diseases and conditions. Abstract: Medicinal herbs and many food ingredients possess favorable biological properties that contribute to their therapeutic activities. -
Designing an Adaptive Building Envelope for Warm-Humid Climate Using Bamboo Veneer As a Hygroscopically Active Material
The Pennsylvania State University The Graduate School RESPONSIVE SKIN: DESIGNING AN ADAPTIVE BUILDING ENVELOPE FOR WARM-HUMID CLIMATE USING BAMBOO VENEER AS A HYGROSCOPICALLY ACTIVE MATERIAL A Thesis in Architecture by Manal Anis 2019 Manal Anis Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Science May 2019 ii The thesis of Manal Anis was reviewed and approved* by the following: Marcus Shaffer Associate Professor of Architecture Thesis Advisor Ute Poerschke Professor of Architecture Interim Head of the Department of Architecture Benay Gursoy Toykoc Assistant Professor of Architecture Rebecca Henn Associate Professor of Architecture Director of Graduate Studies of the Department of Architecture *Signatures are on file in the Graduate School iii abstract Architectural facades that are able to adapt themselves in response to changing climatic conditions have typically been identified with having high-tech complex automated mechanisms, using electronic sensors and actuators. The low-tech and no- tech passive strategies of adaptive façade design based on material responsiveness are still in their infancy. Passive strategies minimize energy and material use while maintaining occupant comfort. This is precisely why such methods require a greater emphasis today as we investigate deeper into the realms of Responsive Architecture. Materials such as bamboo and wood undergo a natural, biological reaction to environmental changes, and, therefore, offer an opportunity for non-mechanical adaption. Bamboo, due to its hygroscopic nature, undergoes constant expansion and contraction with changing levels of atmospheric humidity. From a crafting and constructing perspective, this spontaneous dimensional change – material instability - was seen as an inherent drawback of working with bamboo, with attempts being made to control, mitigate, or counteract the change. -
Hygroscopy-Induced Nanoparticle Reshuffling in Ionic-Gold-Residue
Showcasing research from the Department of Chemistry As featured in: Education, Seoul National University, Seoul, South Korea. Hygroscopy-induced nanoparticle reshuffl ing in ionic-gold-residue-stabilized gold suprananoparticles Ionic precursors play a role in the generation of nanoparticles and infl uence their properties. The excess gold ions facilitate the formation of ultra-small gold nanoparticles and the further assembly of these small nanoparticles into suprananoparticles. The hygroscopic Au(III) residues in the suprananoparticles absorb moisture to form a micro-water pool and, subsequently, the nanoparticles are able to reshuffl e to larger nanoparticles, which is used to detect the water content in organic solvents. Our results indicate that nanoparticle precursors may introduce See Junhua Yu et al., additional characteristics and signifi cantly change the properties Nanoscale Adv., 2019, 1, 1331. of nanostructures. rsc.li/nanoscale-advances Registered charity number: 207890 Nanoscale Advances View Article Online PAPER View Journal | View Issue Hygroscopy-induced nanoparticle reshuffling in ionic-gold-residue-stabilized gold Cite this: Nanoscale Adv.,2019,1, 1331 suprananoparticles† Sungmoon Choi, ‡ Minyoung Lim,‡ Yanlu Zhao and Junhua Yu * Polyethyleneimine (PEI)-stabilized gold nanoparticles were used as a model to understand the roles of ionic precursors in the formation of nanoparticles and the impact of their presence on the nanoparticle properties. The low availability of elemental gold and the stabilization of the just-generated gold nanoparticles by the excess gold ions contributed to the production of ultra-small nearly neutral gold nanoparticles, resulting in properties significantly different from those prepared by conventional methods. The cross-linking between gold ions/PEI/nanoparticles further led to the assembly of these small gold nanoparticles into suprananoparticles that were stable in water. -
Development of Graphene Oxide Based Aerogels
DEVELOPMENT OF GRAPHENE OXIDE BASED AEROGELS A THESIS SUBMITTED TO THE GRADUATE SCHOOL OF NATURAL AND APPLIED SCIENCES OF MIDDLE EAST TECHNICAL UNIVERSITY BY ÖZNUR DOĞAN IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE IN CHEMICAL ENGINEERING AUGUST 2017 Approval of thesis: DEVELOPMENT OF GRAPHENE OXIDE BASED AEROGELS submitted by ÖZNUR DOĞAN in partial fulfillment of the requirements for the degree of Master of Science in Chemical Engineering Department, Middle East Technical University by, Prof. Dr. Gülbin Dural Ünver Dean, Graduate School of Natural and Applied Sciences _______________ Prof. Dr. Halil Kalıpçılar Head of Department, Chemical Engineering _______________ Asst. Prof. Dr. Erhan Bat Supervisor, Chemical Engineering Dept., METU _______________ Examining Committee Members: Prof. Dr. Levent Yılmaz _______________ Chemical Engineering Dept., METU Asst. Prof. Dr. Erhan Bat _______________ Chemical Engineering Dept., METU Assoc. Prof. Dr. Bora Maviş _______________ Mechanical Engineering Dept., Hacettepe University Asst. Prof. Dr. Emre Büküşoğlu _______________ Chemical Engineering Dept., METU Asst. Prof. Dr. Bahar İpek _______________ Chemical Engineering Dept., METU Date: 18.08.2017 I hereby declare that all information in this document has been obtained and presented in accordance with academic rules and ethical conduct. I also declare that, as required by these rules and conduct, I have fully cited and referenced all material and results that are not original to this work. Name, Last Name: Öznur Doğan Signature: iv ABSTRACT DEVELOPMENT OF GRAPHENE OXIDE BASED AEROGELS Doğan, Öznur M.Sc., Department of Chemical Engineering Supervisor: Asst. Prof. Dr. Erhan Bat August 2017, 101 pages Owing to their large surface area, high hydrophobicity and porous structure, graphene oxide based aerogels have been proposed as feasible and economic solutions for the increasing water pollution caused by crude oils, petroleum products and toxic organic solvents. -
Glycine Zwitterion Stabilized by Four Water Molecules
Glycine Zwitterion Stabilized by Four Water Molecules Byeong June Min Department of Physics, Daegu University, Kyungsan 712-714, Korea We performed plane wave density functional theory calculations to survey the potential energy surface of neutral glycine (GlyNE) and its zwitterion (GlyZW) solvated by up to four water molecules. Our previous conformation study of Gly suggests inadequacy of the commonly used local basis function sets in dealing with a high-energy isomer, such as Gly. We find the potential energy surface of GlyNE and GlyZW smoother than usually was thought and without many local minima. Two water molecules can create a local minimum around GlyZW. With three water molecules, the energy difference between GlyNE and GlyZW is reduced to a mere 27 meV with an energy barrier of 115 meV from GlyNE. GlyZW becomes energetically more stable by 122 meV when solvated by four water molecules. Water molecules become catalysts in the tautomerization and sometimes engage in a switching transfer of a proton over the water bridge. Our results are consistent with experimental findings that the effective hydration number of Gly is 3 ~ 4. PACS numbers: Keywords: Glycine, Glycine Zwitterion, Zwitterionization, Microsolvation, Tautomerization Email: [email protected] Fax: +82-53-850-6439, Tel: +82-53-850-6436 1 I. INTRODUCTION Glycine (Gly) is the simplest amino acid with a side chain of single hydrogen atom. Amino acids in the presence of water favor zwitterionic form (GlyZW) in which the hydrogen in the carboxyl group is transferred to the amine group. This is the preliminary step for the formation of peptide bonds in proteins. -
Kinetics of Dissolution and Recrystallization of Sodium Chloride at Controlled Relative Humidity†
Kinetics of Dissolution and Recrystallization of Sodium Chloride at Controlled Relative Humidity† Marina Langlet1*, Frederic Nadaud2, Mohamed Benali1, Isabelle Pezron1, Khashayar Saleh1, Pierre Guigon1, Léa Metlas-Komunjer1 UTC/ESCOM, Équipe d’Accueil “Transformations Intégrées de la Matière Renouvelable” (EA 4297)1 UTC/ESCOM, Service d’Analyses Physico-Chimique2, Abstract Both producers and users of divided solids regularly face the problem of caking after periods of storage and/or transport. Particle agglomeration depends not only on powder water content, tem- perature and applied pressure, but also on the interactions between the solid substance and water molecules present in the atmosphere, i.e. on relative humidity (RH) at which the product is stored. Ambient humidity plays an important role in most events leading to caking: capillary condensation of water at contact points between particles, subsequent dissolution of a solid and formation of a saturated solution eventually followed by precipitation of the solid during the evaporation of water. Here, we focus on the kinetics of dissolution followed by evapo-recrystallization of a hygroscopic so- dium chloride powder under controlled temperature and RH, with the aim of anticipating caking by predicting rates of water uptake and loss under industrial conditions. Precise measurements of water uptake show that the rate of dissolution is proportional to the difference between the imposed RH and deliquescence RH, and follows a model based on the kinetic theory of gases. Evaporation seems to be governed by more complex phenomena related to the mechanism of crystal growth from a supersatu- rated salt solution. Keywords: Sodium chloride, hygroscopy, Knudsen law, vapor sorption, caking humidity, DRH, of 75% at 25℃. -
Structure-Guided Function Discovery of an NRPS-Like Glycine Betaine Reductase for Choline Biosynthesis in Fungi
Structure-guided function discovery of an NRPS-like glycine betaine reductase for choline biosynthesis in fungi Yang Hai (海洋)a, Arthur M. Huangb, and Yi Tanga,b,1 aDepartment of Chemical and Biomolecular Engineering, University of California, Los Angeles, CA 90095; and bDepartment of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095 Edited by Wilfred A. van der Donk, Howard Hughes Medical Institute and University of Illinois, Urbana–Champaign, Urbana, IL, and accepted by Editorial Board Member Stephen J. Benkovic April 10, 2019 (received for review February 27, 2019) Nonribosomal peptide synthetases (NRPSs) and NRPS-like enzymes focused on a fungal CAR-like protein with an unknown function. It have diverse functions in primary and secondary metabolisms. By is distinguished from all other CARs due to an extra C-terminal using a structure-guided approach, we uncovered the function of a YdfG-like short-chain dehydrogenase/reductase domain. We NRPS-like enzyme with unusual domain architecture, catalyzing named this protein ATRR and the corresponding gene atrr after its two sequential two-electron reductions of glycine betaine to choline. unusual domain architecture (A-T-R1-R2). The presence of two Structural analysis based on the homology model suggests cation-π fused R domains in ATRR implies that it could catalyze two con- interactions as the major substrate specificity determinant, which was secutive two-electron reductions of a carboxylic acid to yield an verified using substrate analogs and inhibitors. Bioinformatic analysis alcohol (Fig. 1B). Moreover, a genomic survey reveals that atrr indicates this NRPS-like glycine betaine reductase is highly conserved genes are widespread but exclusive to eukaryotes, mostly in fungi and widespread in kingdom fungi.