Synergistic Pd/Cu-catalysed regio- and stereoselective borylation of allenylic carbonates

2022 ◽  
Author(s):  
Jian Zhao ◽  
Qin Zhong ◽  
Wei-Dong Zhang ◽  
Jia-Yu Zou ◽  
Shi-Sen Li
Keyword(s):  
Neutral Condition ◽  
High Yield

A simple Pd/Cu-catalyzed borylation of allenylic carbonates with B2Pin2 was developed using cheap P(OEt)3 ligand. Under mild neutral condition, 2-boryl 1,3-butadienes could be obtained selectively in moderate to high yield....

scholarly journals OPTIMASI PERLAKUAN POLYETHYLENE GLIKOL (PEG) 6000 TERHADAP ISOLASI AGAROSA RUMPUT LAUT Glacilaria sp.

2017 ◽  
Vol 4 (2) ◽  
pp. 115
Author(s):  
Siti Martinah ◽  
RTM Sutamihardja ◽  
Lilis Sugiarti
Keyword(s):  
Polyethylene Glycol ◽  
Key Words ◽  
Neutral Condition ◽  
High Yield ◽  
Acid Base ◽  
Peg 6000 ◽  
Parameter Test ◽  
Galactose Content

Optimation of Polyethylene Glycol (PEG) 6000 Treatment on Isolation of Agarose Seaweeds of Glacilaria sp         Isolation of agarose from seaweeds (Glacilaria sp) had been done in acid, base, and neutral condition by using polyethylene glycol (PEG) method. Glacilaria sp, Seaweeds that used in this research was cultured by farmer in Muara Gembong, Bekasi. It used PEG with concentration 10%, 15%, 20%, 25%, & 30%. The scope of this research ware determination of seaweeds, seaweeds water content, isolation of agarose from seaweeds, and quality test of agarose. Parameter test of agarose quality include  the strength of gel, the content of sulfat, measurement of galactose content and its proksimat. The high yield was 61,27% r  in PEG 30%. The best quality of agarose was resulted in PEG 20% because of the highest strength of gel was 379,04 g/cm2.The lowest sulfat concentration was 1,33% and galactose was 17,39%.Key words: polyethylene glycol, PEG 6000, agarose, seaweeds, glacilaria sp ABSTRAK         Isolasi agarosa dari rumput laut Glacilaria sp telah dilakukan dalam suasana asam, basa dan netral dengan metode polyethylene glikol (PEG). Rumput lauat yang digunakan adalah Gracilaria sp yang dibudidayakan oleh petani di Muara Gembong, Bekasi dengan perlakuan konsentrasi PEG 10%, 15%, 20%, 25% dan 30%. Ruang lingkup penelitian ini meliputi uji determinasi rumput laut, penetapan kadar air rumput laut, isolasi agarosa dari rumput laut, serta uji kualitas agarosa. Parameter pengujian kualitas agarosa terdiri dari kekuatan gel, kandungan sulfat, dan pengukuran kandungan galaktosa serta proksimatnya. Isolasi agarosa perlakuan konsentrasi polyethylene Glikol (PEG) 6000 pada rumput laut Glacilaria sp diperoleh rendemen paling tinggi terdapat pada perlakuan PEG 30% yaitu sebesar 61,27%. Akan tetapi untuk kualitas agarosa yang paling baik terdapat pada perlakuan konsentrasi PEG 20% karena diperoleh kekuatan gel paling tinggi sebesar 379,04 g/cm2. Kadar sulfat yang paling rendah sebesar 1,33% dan kadar galaktosa sebesar 17,39%.Kata Kunci: polyethylene glikol, PEG 6000, agarosa, rumput laut, glacilaria sp

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

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.

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

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.

Catalytic enantioselective synthesis of indolizino[8,7-b]indole alkaloid derivatives based on the tandem reaction of tertiary enamides

2021 ◽  
Author(s):  
Xin-Ming Xu ◽  
Ming Xie ◽  
Jiazhu Li ◽  
Mei-Xiang Wang
Keyword(s):  
Indole Alkaloid ◽  
Enantioselective Synthesis ◽  
High Yield ◽  
Tandem Reaction ◽  
Indole Derivatives

An exquisite Pybox/Cu(OTf)2-catalyzed asymmetric tandem reaction of tertiary enamides was developed, which enabled the expeditious synthesis of indolizino[8,7-b]indole derivatives in high yield, excellent enantioselectivity and diastereoselectivity.

Purification of Urokinase from Complex Mixtures Using Immobilized Monoclonal Antibody Against Urokinase Light Chain

1983 ◽  
Vol 49 (01) ◽  
pp. 024-027 ◽  
Author(s):  
David Vetterlein ◽  
Gary J Calton
Keyword(s):  
Monoclonal Antibody ◽  
Light Chain ◽  
Culture Media ◽  
Biological Fluids ◽  
Single Step ◽  
High Yield ◽  
Step Method ◽  
Commercial Preparation ◽  
E Coli ◽  
Tissue Culture Media

SummaryThe preparation of a monoclonal antibody (MAB) against high molecular weight (HMW) urokinase light chain (20,000 Mr) is described. This MAB was immobilized and the resulting immunosorbent was used to isolate urokinase starting with an impure commercial preparation, fresh urine, spent tissue culture media, or E. coli broth without preliminary dialysis or concentration steps. Monospecific antibodies appear to provide a rapid single step method of purifying urokinase, in high yield, from a variety of biological fluids.

FloRunTM ‘331’ Peanut Variety

EDIS ◽  
2019 ◽  
Vol 2019 (1) ◽  
Author(s):  
Barry L. Tillman
Keyword(s):  
Seed Size ◽  
Growth Habit ◽  
Yield Potential ◽  
High Yield ◽  
University Of Florida ◽  
High Oleic ◽  
Central Stem ◽  
Research And Education ◽  
The University ◽  
High Yield Potential

FloRunTM ‘331’ peanut variety was developed by the University of Florida, Institute of Food and Agricultural Sciences, North Florida Research and Education Center near Marianna, Florida.  It was released in 2016 because it combines high yield potential with excellent disease tolerance. FloRunTM ‘331’ has a typical runner growth habit with a semi-prominent central stem and medium green foliage.  It has medium runner seed size with high oleic oil chemistry.

Evaluation of germ plasm for resistant to Soybean mosaic virus (SMV)

2020 ◽  
Vol 21 (1) ◽  
pp. 6-9
Author(s):  
Wuye Ria Andayanie
Keyword(s):  
Abiotic Stress ◽  
Environmental Factors ◽  
Mosaic Virus ◽  
Polyclonal Antibody ◽  
Symptom Severity ◽  
Germ Plasm ◽  
Polyclonal Antibodies ◽  
Soybean Mosaic Virus ◽  
High Yield ◽  
High Yields

Soybean superior varieties with high yields and are resistant to abiotic stress have been largely released, although some varieties grown in the field are not resistant to SMV. In addition, the opportunity to obtain lines of hope as prospective varieties with high yield and resistance to SMV is very small. The method for evaluating soybean germplasm is based on serological observations of 98 accessions of leaf samples from SMV inoculation with T isolate. The evaluation results of 98 accessions based on visual observations showed 31 genotypes reacting very resistant or healthy to mild resistant category to SMV T isolate  with a percentage of symptom severity of 0 −30 %. Among 31 genotypes there are 2 genotypes (PI 200485; M8Grb 44; Mlg 3288) with the category of visually very resistant and resistant, respectively and  Mlg 3288  with the category of mild resistant.  They have a good agronomic appearance with a weight of 100 seeds (˃10 g) and react negatively with polyclonal antibodies to SMV, except Mlg 3288 reaction is not consistent, despite the weight of 100 seeds (˃ 10 g). Leaf samples from 98 accessions revealed various symptoms of SMV infection in the field. This diversity of symptoms is caused by susceptibility to accession, when infection occurs, and environmental factors. Keywords—: soybean; genotipe; Soybean mosaic virus (SMV); disease severity; polyclonal  antibody

Sign in / Sign up

Export Citation Format

Share Document