Microbial degradation of quadricyclane-derived tricyclo[2.2.1.02,6]heptan-3-ol in soil

1997 ◽  
Vol 43 (3) ◽  
pp. 300-303 ◽  
Author(s):  
Song Jin ◽  
Norbert G. Swoboda-Colberg ◽  
Patricia J. S. Colberg
Keyword(s):  
Optical Memory ◽  
Transformation Products ◽  
Jet Fuel ◽  
Memory Storage ◽  
Cyclic Hydrocarbon ◽  
Soil Microcosms ◽  
Storage Devices ◽  
Respiration Rates ◽  
Abiotic Transformation ◽  
Soil And Water

Quadricyclane (tetracyclo[3.2.02,7.04,6]heptane) is a strained, saturated cyclic hydrocarbon and a potential environmental contaminant because of uses in solar energy and optical memory storage devices and as a recently proposed additive to jet fuel. Quadricyclane is very unstable in both soil and water, and in the environment it exists as abiotic transformation products, tricyclo[2.2.1.02,6]heptan-3-ol and bicyclo[2.2.1]hept-5-en-2-ol. In soils, tricyclo[2.2.1.02,6]heptan-3-ol is microbially transformed to a C7H8O intermediate which we postulate to be tricyclo[2.2.1.02,6]heptan-3-one. This compound is subsequently biodegraded over several months. Elevated respiration rates in soils amended with tricyclo[2.2.1.02,6]heptan-3-ol provide evidence that it is mineralized to CO2, while bicyclo[2.2.1]hept-5-en-2-ol concentrations in soil microcosms remained unchanged over a period of 8 months.Key words: quadricyclane, biotransformation, biodégradation, tricyclo[2.2.1.02,6]heptan-3-ol, bicyclo[2.2.1]hept-5-en-2-ol.

scholarly journals Implications of NVM Based Storage on Memory Subsystem Management

2020 ◽  
Vol 10 (3) ◽  
pp. 999
Author(s):  
Hyokyung Bahn ◽  
Kyungwoon Cho
Keyword(s):  
Random Access ◽  
Disk Drive ◽  
Main Memory ◽  
Memory Storage ◽  
Storage Device ◽  
Storage Devices ◽  
Large Memory ◽  
Memory Subsystems ◽  
Non Volatile Memory ◽  
Management Techniques

Recently, non-volatile memory (NVM) has advanced as a fast storage medium, and legacy memory subsystems optimized for DRAM (dynamic random access memory) and HDD (hard disk drive) hierarchies need to be revisited. In this article, we explore the memory subsystems that use NVM as an underlying storage device and discuss the challenges and implications of such systems. As storage performance becomes close to DRAM performance, existing memory configurations and I/O (input/output) mechanisms should be reassessed. This article explores the performance of systems with NVM based storage emulated by the RAMDisk under various configurations. Through our measurement study, we make the following findings. (1) We can decrease the main memory size without performance penalties when NVM storage is adopted instead of HDD. (2) For buffer caching to be effective, judicious management techniques like admission control are necessary. (3) Prefetching is not effective in NVM storage. (4) The effect of synchronous I/O and direct I/O in NVM storage is less significant than that in HDD storage. (5) Performance degradation due to the contention of multi-threads is less severe in NVM based storage than in HDD. Based on these observations, we discuss a new PC configuration consisting of small memory and fast storage in comparison with a traditional PC consisting of large memory and slow storage. We show that this new memory-storage configuration can be an alternative solution for ever-growing memory demands and the limited density of DRAM memory. We anticipate that our results will provide directions in system software development in the presence of ever-faster storage devices.

scholarly journals Turn-off mode fluorescent norbornadiene-based photoswitches

2018 ◽  
Vol 20 (36) ◽  
pp. 23195-23201 ◽  
Author(s):  
Behabitu Ergette Tebikachew ◽  
Fredrik Edhborg ◽  
Nina Kann ◽  
Bo Albinsson ◽  
Kasper Moth-Poulsen
Keyword(s):  
Optical Memory ◽  
Memory Storage ◽  
Photochromic Molecules

To explore the potential of negative photochromic molecules for possible optical memory storage applications, we have here synthesized and studied a series of four norbornadiene–quadricyclane (NBD–QC) photoswitching molecules.

Polymer mechanics and tribology

2018 ◽  
Vol 70 (4) ◽  
pp. 764-772 ◽  
Author(s):  
Nikolai K. Myshkin ◽  
Alexander Kovalev
Keyword(s):  
Polymer Composites ◽  
Contact Mechanics ◽  
Tribological Behavior ◽  
Tribological Performance ◽  
Memory Storage ◽  
Polymer Mechanics ◽  
Micro Electro Mechanical Systems ◽  
Content Type ◽  
Storage Devices ◽  
Functional Additives

Purpose The purpose of this paper is to review the advances in mechanics and tribology of polymers and polymer-based materials. It is focused on the understanding of the correlation of contact mechanics and the tribological behavior of polymers and polymer composites by taking account of surface forces and adhesion in the contact. Design/methodology/approach Mechanical behavior of polymers is considered a viscoelasticity. Tribological performance is estimated while considering the parts of deformation and adhesion in friction arising in the contact. Surface energy, roughness, load and temperature effects on the tribological behavior of polymers are evaluated. Polymer composites produced by reinforcing and by the addition of functional additives are considered as materials for various applications in tribology. Particular attention is given to polymer-based nanocomposites. Findings A review of studies in tribology has shown that polymer-based materials can be most successfully used as self-lubricating components of sliding bearings. The use of the fillers provides changes in the tribological performance of neat polymers and widens their areas of application in the industry. Thin polymer films were found to be prospective lubricants for memory storage devices, micro-electro-mechanical systems and precision mechanisms. Further progress in polymer tribology should be achieved on solving the problems of contact mechanics, surface physics and tribochemistry by taking account of the scale factor. Originality/value The review is based on the experience of the authors in polymer mechanics and tribology, their research data and on data of many other literature sources published in this area. It can be useful for specialists in polymer research and industrial engineers working in tribology and industrial lubrication.

Reversible single-crystal-to-single-crystal conversion of a photoreactive coordination network for rewritable optical memory storage

2020 ◽  
Vol 56 (13) ◽  
pp. 1984-1987 ◽  
Author(s):  
Ni-Ya Li ◽  
Jing-Min Chen ◽  
Xiao-Yan Tang ◽  
Guo-Ping Zhang ◽  
Dong Liu
Keyword(s):  
Single Crystal ◽  
Optical Memory ◽  
Memory Storage ◽  
Coordination Network

Reversible single-crystal-to-single-crystal photoreaction of a coordination network exhibits switchable fluorescence for rewritable optical memory storage.

Mastering nanostructured materials through H-bonding recognitions at interfaces

2010 ◽  
Vol 82 (4) ◽  
pp. 917-929 ◽  
Author(s):  
Stefan Mohnani ◽  
Anna Llanes-Pallas ◽  
Davide Bonifazi
Keyword(s):  
Hydrogen Bonding ◽  
Electronic Properties ◽  
Nanostructured Materials ◽  
Self Assembly ◽  
The Self ◽  
Memory Storage ◽  
Technological Application ◽  
Storage Devices ◽  
Hydrogen Bonding Interactions ◽  
Fundamental Research

The controlled engineering of functional architectures composed of π-systems with unusual opto-electronic properties is currently being investigated intensively from both fundamental research and technological application viewpoints. In particular, the exploitation of the supramolecular approach for the facile construction of multidimensional architectures, featuring cavities capable of hosting functional molecules, could be used in several applications, such as nanomedicine, molecular-based memory storage devices, and sensors. This paper highlights our recent strategies to use hydrogen-bonding interactions to prepare nanostructured functional architectures via the self-assembly of organic molecular modules studied at different interfaces.

Sign in / Sign up

Export Citation Format

Share Document