Directional design and synthesis of high-yield hollow Fe-MFI zeolite encapsulating ultra-small Fe2O3 nanoparticles by using mother liquid

AS1411@GMBS@EG@TiO2@Fe2O3 nanoparticle is an effective and safe pH-responsive sustained release system for targeted drug delivery into nucleolin-positive cells.

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High Electrical Conductivity in Three-Dimensional Porphyrin-Phosphonate Metal Organic-Frameworks

10.26434/chemrxiv.13653050.v1 ◽

2021 ◽

Author(s):

Yunus Zorlu ◽

Patrik Tholen ◽

Mehmet Menaf Ayhan ◽

Ceyda Bayraktar ◽

Gabriel Hanna ◽

...

Keyword(s):

Electrical Conductivity ◽

Low Cost ◽

Metal Organic Framework ◽

Three Dimensional ◽

High Yield ◽

Electrically Conductive ◽

Design And Synthesis ◽

Metal Organic ◽

Indirect Band Gap ◽

Organic Framework

Herein, we report the design and synthesis of a highly electrically conductive and microporous three-dimensional zinc-phosphonate metal-organic framework [Zn(Cu-p-H4TPPA)] ⋅2 (CH3)2NH2+ (designated as GTUB3), constructed using the 5,10,15,20‐tetrakis [p‐phenylphosphonic acid] porphyrin (p-H8TPPA) organic linker. GTUB3 has an indirect band gap of 1.64 eV and a high average electrical conductivity of 4 S/m, making it a rare example of an electrically conductive zinc metal-organic framework. The N2-accessible geometric surface area of GTUB3, as predicted by molecular simulations, is 671 m2/g. Owing to its simple, high-yield synthesis at low temperatures, porosity, and electrical conductivity, GTUB3 may be used as a low-cost electrode material in next generation phosphonate-supercapacitors.

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The design and synthesis of nonpeptide compounds as mimics of a conformation of methionine-enkephaline

Canadian Journal of Chemistry ◽

10.1139/v82-151 ◽

1982 ◽

Vol 60 (8) ◽

pp. 1019-1029 ◽

Cited By ~ 22

Author(s):

Patrice C. Belanger ◽

Claude Dufresne ◽

John Scheigetz ◽

Robert N. Young ◽

James P. Springer ◽

...

Keyword(s):

Double Bond ◽

Computer Modeling ◽

High Yield ◽

Side Chain ◽

Active Conformation ◽

Methionine Enkephalin ◽

Design And Synthesis ◽

Structural Template ◽

Subsequent Addition

A model for the active conformation of methionine-enkephalin containing a β-turn was derived from computer modeling. Using a trans-perhydronaphthalene as a structural template and a mimic of the β-turn, target compounds were designed and synthesized. Thus, a key intermediate, trans-3-oxo-5β-formamidomethyl-8a-phenylmethylperhydronaphthalene, was prepared by two different routes from cyclohexanone.The addition of a methionine-like side-chain to this key intermediate was best achieved by a reaction with the anion of methyl 2-trimethylsilyl-4-methylthiobutanoate. This led to the preparation of an exo-tetrasubstituted double bond in high yield. Subsequent addition of tyrosine through coupling with the 5β-aminomethyl group provided the desired perhydronaphthalene mimics of met-enkaphalin.

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Design and Synthesis of Lipopeptide - Carbohydrate Assembled Multivalent Vaccine Candidates Using Native Chemical Ligation

Australian Journal of Chemistry ◽

10.1071/ch09065 ◽

2009 ◽

Vol 62 (9) ◽

pp. 993 ◽

Cited By ~ 14

Author(s):

Wei Zhong ◽

Mariusz Skwarczynski ◽

Yoshio Fujita ◽

Pavla Simerska ◽

Michael F. Good ◽

...

Keyword(s):

Tertiary Structure ◽

Native Chemical Ligation ◽

High Yield ◽

Antigenic Peptides ◽

Chemical Ligation ◽

Vaccine Candidates ◽

Multivalent Vaccine ◽

Peptide Antigens ◽

Design And Synthesis ◽

Α Helix

Development of a synthetic vaccine against group A streptococcal infection is increasingly paramount due to the induction of autoimmunity by the main virulent factor – M protein. Peptide vaccines, however, are generally poorly immunogenic, necessitating administration with carriers and adjuvants. One of the promising approaches to deliver antigenic peptides is to assemble peptides on a suitable template which directs the attached peptides to form a well defined tertiary structure. For self-adjuvanting human vaccines, the conjugation of immunostimulatory lipids has been demonstrated as a potentially safe method. This study describes the design and optimized synthesis of two lipopeptide conjugated carbohydrate templates and the assembling of peptide antigens. These lipopeptide–carbohydrate assembled multivalent vaccine candidates were obtained in high yield and purity when native chemical ligation was applied. Circular dichroism studies indicated that the template-assembled peptides form four α-helix bundles. The developed technique extends the use of carbohydrate templates and lipopeptide conjugates for producing self-adjuvanting and topology-controlled vaccine candidates.

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Mesoporous MFI Zeolite Nanosponge Supporting Cobalt Nanoparticles as a Fischer–Tropsch Catalyst with High Yield of Branched Hydrocarbons in the Gasoline Range

ACS Catalysis ◽

10.1021/cs500784v ◽

2014 ◽

Vol 4 (11) ◽

pp. 3919-3927 ◽

Cited By ~ 62

Author(s):

Jeong-Chul Kim ◽

Seungyeop Lee ◽

Kanghee Cho ◽

Kyungsu Na ◽

Changq Lee ◽

...

Keyword(s):

Cobalt Nanoparticles ◽

High Yield ◽

Mfi Zeolite ◽

Fischer Tropsch ◽

Branched Hydrocarbons

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High Electrical Conductivity in Three-Dimensional Porphyrin-Phosphonate Metal Organic-Frameworks

10.26434/chemrxiv.13653050 ◽

2021 ◽

Author(s):

Yunus Zorlu ◽

Patrik Tholen ◽

Mehmet Menaf Ayhan ◽

Ceyda Bayraktar ◽

Gabriel Hanna ◽

...

Keyword(s):

Electrical Conductivity ◽

Low Cost ◽

Metal Organic Framework ◽

Three Dimensional ◽

High Yield ◽

Electrically Conductive ◽

Design And Synthesis ◽

Metal Organic ◽

Indirect Band Gap ◽

Organic Framework

Herein, we report the design and synthesis of a highly electrically conductive and microporous three-dimensional zinc-phosphonate metal-organic framework [Zn(Cu-p-H4TPPA)] ⋅2 (CH3)2NH2+ (designated as GTUB3), constructed using the 5,10,15,20‐tetrakis [p‐phenylphosphonic acid] porphyrin (p-H8TPPA) organic linker. GTUB3 has an indirect band gap of 1.64 eV and a high average electrical conductivity of 4 S/m, making it a rare example of an electrically conductive zinc metal-organic framework. The N2-accessible geometric surface area of GTUB3, as predicted by molecular simulations, is 671 m2/g. Owing to its simple, high-yield synthesis at low temperatures, porosity, and electrical conductivity, GTUB3 may be used as a low-cost electrode material in next generation phosphonate-supercapacitors.

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Quality films from carbon fiber evaporation for thorough coverage of TEM grids

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104157 ◽

1988 ◽

Vol 46 ◽

pp. 418-419

Author(s):

N. Tempel ◽

M. C. Ledbetter

Keyword(s):

Electron Microscopy ◽

High Resolution Electron Microscopy ◽

Carbon Films ◽

Low Noise ◽

Vacuum Evaporation ◽

High Yield ◽

Good Adhesion ◽

Noise Structure ◽

Resolution Electron ◽

Carbon Foils

Carbon films have been a support of choice for high resolution electron microscopy since the introduction of vacuum evaporation of carbon. The desirable qualities of carbon films and methods of producing them has been extensively reviewed. It is difficult to get a high yield of grids by many of these methods, especially if virtually all of the windows must be covered with a tightly bonded, quality film of predictable thickness. We report here a method for producing carbon foils designed to maximize these attributes: 1) coverage of virtually all grid windows, 2) freedom from holes, wrinkles or folds, 3) good adhesion between film and grid, 4) uniformity of film and low noise structure, 5) predictability of film thickness, and 6) reproducibility.Our method utilizes vacuum evaporation of carbon from a fiber onto celloidin film and grid bars, adhesion of the film complex to the grid by carbon-carbon contact, and removal of the celloidin by acetone dissolution. Materials must be of high purity, and cleanliness must be rigorously maintained.

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Prostatic Acid Phosphatase (PAP) Differentiated Ultracytochemically from Lysosomal Acid Phosphate in the Rat with a PAP/Specific Substrate, Phosphorylcholine

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100115870 ◽

1975 ◽

Vol 33 ◽

pp. 450-451

Author(s):

W. Allen Shannon ◽

José A. Serrano ◽

Hannah L. Wasserkrug ◽

Anna A. Serrano ◽

Arnold M. Seligman

Keyword(s):

Acid Phosphatase ◽

Phosphate Buffer ◽

Prostatic Carcinoma ◽

Prostatic Acid Phosphatase ◽

Chemotherapeutic Agents ◽

Specific Substrate ◽

Acid Phosphate ◽

Lysosomal Acid ◽

Design And Synthesis ◽

New Chemotherapeutic Agents

During the design and synthesis of new chemotherapeutic agents for prostatic carcinoma based on phosphorylated agents which might be enzyme-activated to cytotoxicity, phosphorylcholine, [(CH3)3+NCH2CH2OPO3Ca]Cl-, has been indicated to be a very specific substrate for prostatic acid phosphatase (PAP). This phenomenon has led to the development of specific histochemical and ultracytochemical methods for PAP using modifications of the Gomori lead method for acid phosphatase. Comparative histochemical results in prostate and kidney of the rat have been published earlier with phosphorylcholine (PC) and β-glycerophosphate (βGP). We now report the ultracytochemical results.Minced tissues were fixed in 3% glutaraldehyde-0.1 M phosphate buffered (pH 7.4) for 1.5 hr and rinsed overnight in several changes of 0.05 M phosphate buffer (pH 7.0) containing 7.5% sucrose. Tissues were incubated 30 min to 2 hr in Gomori acid phosphatase medium (2) containing 0.1 M substrate, either PC or βGP.

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Tailoring microstructures of materials through biomimetics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100148332 ◽

1993 ◽

Vol 51 ◽

pp. 500-501

Author(s):

Mehmet Sarikaya ◽

Ilhan A. Aksay

Keyword(s):

Chemical Properties ◽

Design And Synthesis ◽

Structure Sensitive ◽

Macro Scale ◽

Methods Of Synthesis ◽

Successive Level ◽

Engineering Materials ◽

Physical And Chemical ◽

And Chemical Properties ◽

Synthesis Of Materials

Biomimetics involves investigation of structure, function, and methods of synthesis of biological composite materials. The goal is to apply this information to the design and synthesis of materials for engineering applications.Properties of engineering materials are structure sensitive through the whole spectrum of dimensions from nanometer to macro scale. The goal in designing and processing of technological materials, therefore, is to control microstructural evolution at each of these dimensions so as to achieve predictable physical and chemical properties. Control at each successive level of dimension, however, is a major challenge as is the retention of integrity between successive levels. Engineering materials are rarely fabricated to achieve more than a few of the desired properties and the synthesis techniques usually involve high temperature or low pressure conditions that are energy inefficient and environmentally damaging.In contrast to human-made materials, organisms synthesize composites whose intricate structures are more controlled at each scale and hierarchical order.

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Effects of high pressure on the crystallization of carbon fiber reinforced polyetheretherketone (CF/PEEK) laminate composites

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100177519 ◽

1990 ◽

Vol 48 (4) ◽

pp. 876-877

Author(s):

Hong-Ming Lin ◽

C. H. Liu ◽

R. F. Lee

Keyword(s):

High Pressure ◽

Carbon Fiber ◽

Sample Surface ◽

High Yield ◽

Fiber Reinforced ◽

Laminate Composites ◽

Peek Composite ◽

Continuous Carbon Fiber ◽

Carbon Fiber Reinforced

Polyetheretherketone (PEEK) is a crystallizable thermoplastic used as composite matrix materials in application which requires high yield stress, high toughness, long term high temperature service, and resistance to solvent and radiation. There have been several reports on the crystallization behavior of neat PEEK and of CF/PEEK composite. Other reports discussed the effects of crystallization on the mechanical properties of PEEK and CF/PEEK composites. However, these reports were all concerned with the crystallization or melting processes at or close to atmospheric pressure. Thus, the effects of high pressure on the crystallization of CF/PEEK will be examined in this study.The continuous carbon fiber reinforced PEEK (CF/PEEK) laminate composite with 68 wt.% of fibers was obtained from Imperial Chemical Industry (ICI). For the high pressure experiments, HIP was used to keep these samples under 1000, 1500 or 2000 atm. Then the samples were slowly cooled from 420 °C to 60 °C in the cooling rate about 1 - 2 degree per minute to induce high pressure crystallization. After the high pressure treatment, the samples were scanned in regular DSC to study the crystallinity and the melting temperature. Following the regular polishing, etching, and gold coating of the sample surface, the scanning electron microscope (SEM) was used to image the microstructure of the crystals. Also the samples about 25mmx5mmx3mm were prepared for the 3-point bending tests.

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