Influence of the Loading and Strain Rates on the Strength Properties and Formability of Higher-Strength Sheet

The paper analyses the influence of the loading rate in the interval from 1 to 1000 mm/min, which corresponds to the tensile machine working range, on the strength properties and the formability characteristics obtained on standard and notched test bars made of H340 LAD steel strips. The combination of the loading rate and the test bar type made it possible to obtain the relationships of monitored variables in the strain rate interval from 10–4 to 10 s–1. In this interval, the strength properties of the tested strips thick 1, 1,5 and 1,8 mm exponentially increase, but formability does not change up to the strain rate of 1 s–1

Occurrence of Idiosepius (Mollusca: Cephalopoda) in Indonesian Waters

Jenis Idiosepius (Mollusca: Cephalopoda) di perairan Indonesia. Informasi dan penelitiantentang sotong mini “pygmy squid” marga Idiosepius yang ada di Indonesia sangat kurang,meskipun pernah dilaporkan setidaknya ada tiga jenis dijumpai di Ambon, Ternate, Banda,Balikpapan, Sibolga dan Lombok. Dalam tulisan ini diuraikan karakter morfologi, habitat dandistribusi empat jenis sotong mini jenis I. picteti, I. pygmaeus, I. biserialis dan I. pygmaeusherbereri. Karena ukurannya yang sangat kecil, jenis sotong ini tidak diminati oleh paranelayan, sehingga hanya sedikit data yang diketahui mengenai pertumbuhan, reproduksi dansiklus hidupnya. Penelitian ini bertujuan untuk memberikan gambaran ringkas tentangsistematik, habitat, siklus hidup dan distribusi Idiosepius. Hasil studi ini mencatat lokasi baru(new record) ditemukannya sotong mini jenis I. biserialis dan I. pygmaeus khusus dari perairanpantai di Lombok. Hasil penelitian juga menunjukkan bahwa beberapa jenis Idiosepiusmemiliki sebaran yang luas di perairan Indonesia kecuali jenis I. picteti hingga saat ini hanyadijumpai di Ambon. Hasil studi diharapakan menambah khasanah pengetahuan tentang sotongmungil ini sekaligus memacu para peneliti untuk lebih memperhatikan genus ini

The use of mathematical model of hardness spread in the research on the property of cast-iron molds

The paper determines the range and form of a surface layer of a spheroid cast iron founding. It presents proofs of the possibility to form an operative surface of a product in the range of an intermediate surface layer of the cast. Based on research and experience, one has stated that the hardness spread and structures in cross sections of the wall of a cast are the most representative parameters determining the range of the surface layer of the iron cast

Free-standing and binder-free highly N-doped carbon/sulfur cathodes with tailorable loading for high-areal-capacity lithium-sulfur batteries

A practical high-loading Li–S battery is realized by using free-standing and highly conductive N-doped carbon paper as sulfur host.</p

Cleavable Biotin Probes for Labeling of Biomolecules via Azide−Alkyne Cycloaddition

The azide−alkyne cycloaddition provides a powerful tool for bio-orthogonal labeling of proteins, nucleic acids, glycans, and lipids. In some labeling experiments, e.g., in proteomic studies involving affinity purification and mass spectrometry, it is convenient to use cleavable probes that allow release of labeled biomolecules under mild conditions. Five cleavable biotin probes are described for use in labeling of proteins and other biomolecules via azide−alkyne cycloaddition. Subsequent to conjugation with metabolically labeled protein, these probes are subject to cleavage with either 50 mM Na_2S_2O_4, 2% HOCH_2CH_2SH, 10% HCO_2H, 95% CF_3CO_2H, or irradiation at 365 nm. Most strikingly, a probe constructed around a dialkoxydiphenylsilane (DADPS) linker was found to be cleaved efficiently when treated with 10% HCO_2H for 0.5 h. A model green fluorescent protein was used to demonstrate that the DADPS probe undergoes highly selective conjugation and leaves a small (143 Da) mass tag on the labeled protein after cleavage. These features make the DADPS probe especially attractive for use in biomolecular labeling and proteomic studies

Cost-effective rhamnolipid production by Burkholderia thailandensis E264 using agro-industrial residues

The agro-industrial by-products corn steep liquor (CSL) and olive mill wastewater (OMW) were evaluated as low-cost substrates for rhamnolipid production by Burkholderia thailandensis E264. In a culture medium containing CSL (7.5% (v/v)) as sole substrate, B. thailandensis E264 produced 175 mg rhamnolipid/L, which is about 1.3 times the amount produced in the standard medium, which contains glycerol, peptone, and meat extract. When the CSL medium was supplemented with OMW (10% (v/v)), rhamnolipid production further increased up to 253 mg/L in flasks and 269 mg/L in a bioreactor. Rhamnolipids produced in CSL+OMW medium reduced the surface tension up to 27.1 mN/m, with a critical micelle concentration of 51 mg/L, better than the values obtained with the standard medium (28.9 mN/m and 58 mg/L, respectively). However, rhamnolipids produced in CSL+OMW medium displayed a weak emulsifying activity when compared to those produced in the other media. Whereas di-rhamnolipid congeners represented between 90 and 95% of rhamnolipids produced by B. thailandensis E264 in CSL and the standard medium, the relative abundance of mono-rhamnolipids increased up to 55% in the culture medium containing OMW. The difference in the rhamnolipid congeners produced in each medium explains their different surface-active properties. To the best of our knowledge, this is the first report of rhamnolipid production by B. thailandensis using a culture medium containing agro-industrial by-products as sole ingredients. Furthermore, rhamnolipids produced in the different media recovered around 60% of crude oil from contaminated sand, demonstrating its potential application in the petroleum industry and bioremediation.This study was funded by PARTEX Oil and Gas, the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and LABBELS – Associate Laboratory in Biotechnology, Bioengineering and Microelectromechanical Systems, LA/P/0029/2020, and the National Science Centre (Poland), under the scope of the project 2020/37/B/NZ9/01519.info:eu-repo/semantics/publishedVersio

Challenges for Developing Rechargeable Room-Temperature Sodium Oxygen Batteries

© 2018 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim The development of high energy-density and low-cost energy storage devices requires new chemistry beyond the horizon of current state-of-the-art lithium-ion batteries. Recently, sodium/oxygen (Na/O2) batteries have attracted great attention as one possible battery type among the new generation of rechargeable batteries. They convince with superior energy density, a relatively simple cell reaction, and abundance of sodium. Research on Na/O2 batteries has progressed quickly in recent years. However, a fundamental understanding underpinning the complex chemical/electrochemical side reactions is still insufficient, and many challenges remain unsolved for real practical applications. Herein, recent achievements and remaining issues for the development of rechargeable Na/O2 batteries are summarized. The discussion focuses on cell reaction mechanisms as well as cathode materials, sodium anodes, and electrolytes as key components of this type of battery. Furthermore, perspectives for future research and technological advances of Na/O2 batteries are outlined