Design and control of gas diffusion process in a nanoporous soft crystal

Science ◽  
2019 ◽  
Vol 363 (6425) ◽  
pp. 387-391 ◽  
Author(s):  
Cheng Gu ◽  
Nobuhiko Hosono ◽  
Jia-Jia Zheng ◽  
Yohei Sato ◽  
Shinpei Kusaka ◽  
...  
Keyword(s):  
Diffusion Process ◽  
Rational Design ◽  
Regulatory System ◽  
Gas Diffusion ◽  
Ambient Conditions ◽  
Guest Molecules ◽  
Flip Flop ◽  
Soft Crystal ◽  
And Control ◽  
And Storage

Design of the gas-diffusion process in a porous material is challenging because a contracted pore aperture is a prerequisite, whereas the channel traffic of guest molecules is regulated by the flexible and dynamic motions of nanochannels. Here, we present the rational design of a diffusion-regulatory system in a porous coordination polymer (PCP) in which flip-flop molecular motions within the framework structure provide kinetic gate functions that enable efficient gas separation and storage. The PCP shows substantial temperature-responsive adsorption in which the adsorbate molecules are differentiated by each gate-admission temperature, facilitating kinetics-based gas separations of oxygen/argon and ethylene/ethane with high selectivities of ~350 and ~75, respectively. Additionally, we demonstrate the long-lasting physical encapsulation of ethylene at ambient conditions, owing to strongly impeded diffusion in distinctive nanochannels.

U.S. Regulatory Approaches: A Critical Appraisal

1992 ◽  
Vol 25 (3) ◽  
pp. 13-21
Author(s):  
R. L. Williamson
Keyword(s):  
Decision Making ◽  
Command And Control ◽  
Regulatory System ◽  
Federal Agencies ◽  
Toxic Substances ◽  
Use Of Technology ◽  
Treatment Technologies ◽  
New Treatment ◽  
And Control ◽  
The Impact

The American approach to environmental regulation is characterized by fragmentation of responsibilities, primary reliance on command and control regulations, extraordinary complexity, a preference for identifiable standards, and heavy resort to litigation. This system has provided important benefits, including significant reduction of environmental contamination, substantial use of science in decision-making, broad participatory rights, and the stimulation of new treatment technologies. However, these gains have been achieved at excessive cost. Too much reliance is placed on command and control methods and especially on technology-based standards. There is too much resort to litigation, and inadequate input from science. Participatory rights are being undermined, and there is a poor allocation of decision-making among the federal agencies and the states. Over-regulation sometimes leads to under-regulation, and insufficient attention is given to the impact on small entities. The responsibility for these difficulties rests with everyone, including the federal agencies, the Congress, the general public and the courts. Changes in the regulatory system are needed. We should abandon the use of technology-based standards to control toxic substances under the Clean Water Act in favor of strong health- and environmentally based standards, coupled with taxes on toxic substances in wastewater.

Recent advances in the rational design of 2D MXenes in energy conversion and storage systems

2021 ◽  
Author(s):  
Nayab Sheikh ◽  
Muhammad Bilal Tahir ◽  
Nisar Fatima ◽  
Muhammad Sagir ◽  
Muhammad Pervaiz ◽  
...  
Keyword(s):  
Energy Conversion ◽  
Rational Design ◽  
Storage Systems ◽  
Recent Advances ◽  
Energy Conversion And Storage ◽  
And Storage

Disaster and Digital Libraries in Developing Countries

2016 ◽  
pp. 534-559 ◽  
Author(s):  
Goodluck Ifijeh ◽  
Jerome Idiegbeyan-Ose ◽  
Chidi D. Isiakpona ◽  
Julie Ilogho
Keyword(s):  
Developing Countries ◽  
Information And Communication Technology ◽  
Disaster Management ◽  
Communication Technology ◽  
Digital Libraries ◽  
Prevention And Control ◽  
Information And Communication ◽  
Information Generation ◽  
And Control ◽  
And Storage

Digital libraries have become a modern day phenomenon. Their roles in information generation,organization, dissemination and storage cannot be overemphasized. This chapter articulates the importance of digital libraries and the need to preserve them from disasters. It highlights the causes and effects of disasters in digital libraries. Prevention and management of disasters were also discussed. Issues and challenges around information and communication technology (ICT), that has direct bearings on digital libraries and disaster management in developing countries were raised. In addition, recommendations were made on how to improve on disaster prevention and control.

Growing Model of Interfacial Layer between Alloy Layer and Matrix in Diffusion Process of Hot Dip Aluminized Steel

2010 ◽  
Vol 154-155 ◽  
pp. 1203-1208
Author(s):  
Wei Zhang ◽  
Shi Jie Fang ◽  
Long Xing Li
Keyword(s):  
Diffusion Process ◽  
Intermetallic Compounds ◽  
Interfacial Layer ◽  
Alloy Layer ◽  
Binding Ability ◽  
Diffusion Parameters ◽  
Aluminized Steel ◽  
And Control

Intermetallic compounds layer will be formed at the interfaces between alloy layer and matrix in the diffusion process of hot dip aluminized steel, which is beneficial to enhance the binding ability of alloy layer with matrix. However, when the thickness of intermetallic compounds exceeds the certain value, the vast extending force of interfacial void will cause the crack of intermetallic compounds and greatly weaken the spall resistance of aluminized layer. Therefore it is very important for the applications of hot dip aluminized steel to research and control the formation of intermetallic compounds at the interfaces. According to the characteristics of diffusion process of hot dip aluminized steel, the growing model of intermetallic compounds were established in the paper. The computed results were in accord with the experimental value. It can provide reference to the choice of the diffusion parameters of hot dip aluminized steel.

Solvent exchange in a metal–organic framework single crystal monitored by dynamicin situX-ray diffraction

2017 ◽  
Vol 73 (4) ◽  
pp. 669-674 ◽  
Author(s):  
Jordan M. Cox ◽  
Ian M. Walton ◽  
Gage Bateman ◽  
Cassidy A. Benson ◽  
Travis Mitchell ◽  
...  
Keyword(s):  
Rational Design ◽  
Metal Organic Framework ◽  
X Ray Diffraction ◽  
Guest Molecules ◽  
Time Resolved ◽  
Ethanol Solvate ◽  
Significant Step ◽  
Metal Organic ◽  
Flexible Metal ◽  
Organic Framework

Understanding the processes by which porous solid-state materials adsorb and release guest molecules would represent a significant step towards developing rational design principles for functional porous materials. To elucidate the process of liquid exchange in these materials, dynamicin situX-ray diffraction techniques have been developed which utilize liquid-phase chemical stimuli. Using these time-resolved diffraction techniques, the ethanol solvation process in a flexible metal–organic framework [Co(AIP)(bpy)0.5(H2O)]·2H2O was examined. The measurements provide important insight into the nature of the chemical transformation in this system including the presence of a previously unreported neat ethanol solvate structure.

Intelligent Automation and Control Technology Based on Energy Meter Testing and Storage System Construction Model

2013 ◽  
Vol 455 ◽  
pp. 402-407 ◽  
Author(s):  
Huai Ling Shao ◽  
Zhi Qiang He ◽  
Er Qiang Xu ◽  
Lei Liu
Keyword(s):  
Storage Systems ◽  
Storage System ◽  
Risk Control ◽  
Control Measures ◽  
System Construction ◽  
Energy Meter ◽  
Automation And Control ◽  
Construction Model ◽  
And Control ◽  
And Storage

Explains smart energy meter testing and storage systems,the background,analysis of the current development of the industry at home and abroad,focusing on Metrology Centre of Electric Power of Henan meter verification and storage systems,the content of the system in key technologies summary,the process of building the proposed risk control measures.

scholarly journals The molecular recognition of phosphatidic acid by an amphipathic helix in Opi1

2018 ◽  
Vol 217 (9) ◽  
pp. 3109-3126 ◽  
Author(s):  
Harald F. Hofbauer ◽  
Michael Gecht ◽  
Sabine C. Fischer ◽  
Anja Seybert ◽  
Achilleas S. Frangakis ◽  
...  
Keyword(s):  
Phosphatidic Acid ◽  
Rational Design ◽  
Acyl Chain ◽  
Membrane Biogenesis ◽  
Amphipathic Helix ◽  
New Feature ◽  
Dynamics Simulations ◽  
Membrane Recognition ◽  
And Control

A key event in cellular physiology is the decision between membrane biogenesis and fat storage. Phosphatidic acid (PA) is an important intermediate at the branch point of these pathways and is continuously monitored by the transcriptional repressor Opi1 to orchestrate lipid metabolism. In this study, we report on the mechanism of membrane recognition by Opi1 and identify an amphipathic helix (AH) for selective binding of PA over phosphatidylserine (PS). The insertion of the AH into the membrane core renders Opi1 sensitive to the lipid acyl chain composition and provides a means to adjust membrane biogenesis. By rational design of the AH, we tune the membrane-binding properties of Opi1 and control its responsiveness in vivo. Using extensive molecular dynamics simulations, we identify two PA-selective three-finger grips that tightly bind the PA phosphate headgroup while interacting less intimately with PS. This work establishes lipid headgroup selectivity as a new feature in the family of AH-containing membrane property sensors.

Legislation On Oil Pollution Prevention And Control During Petroleum Production

1988 ◽  
pp. 1-6 ◽  
Author(s):  
Dr. Abu Azam Md. Yassin
Keyword(s):  
Prevention And Control ◽  
Oil And Gas ◽  
Oil Pollution ◽  
Pollution Prevention ◽  
The World ◽  
Pollution Prevention And Control ◽  
Offshore Oil And Gas ◽  
And Control ◽  
Offshore Oil ◽  
And Storage

Malaysia has long been victim of oil pollution well before the start of her own offshore exploitation of oil. With the effort to exploit offshore oil and gas, Malaysia has now become causer of pollution herself. Legislation existed for oil pollution prevention and control, along each and every stage of offshore petroleum operations which include exploration, development, production, transportation, treatment and storage. But procedures to explain the existing legislation is lacking and hence it is important to expound the existing legislation for controlling and preventing oil pollution from offshore operation in line with current practices around the world.

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