The leaderette for two special columns

The special column of ＂Invasive Species and Global Change＂ is the outcome of the International Symposium on Invasive Plants and Global Change in Urumqi, China in 2012. Invasive species, being responsible for half to two-thirds of global species extinctions, pose a significant threat to ecosystems. Furthermore, climate change is exacerbating this problem, and thus promotes the introduction, establishment, and spread of invasive species. Aiming to provide a theoretical basis for the sustainable management of arid ecosystems, this column, which is to cover two issues, devotes a considerable number of pages to the discussion on species invasion mechanisms and comparative studies on large regional scales. Special thanks are due to our guest editor Professor Robert S NOWAK （University of Nevada, Reno of the USA） for his supportive organizational and editorial efforts. Xinjiang Institute of Ecology and Geography organized the Symposium and provided finan- cial support that made the Symposium and this special column possible.

Frame property of unequal storey height with specially shaped columns under cyclic loading

A 1/3-scale reinfored concrete(RC) frame of unequal storey height with specially shaped columns was tested under low frequency cyclic loading.The damage characteristic,bearing capacity,deformation capacity and ductility were analyzed.The restoring force model of the frame was obtained based on the study of the hysteresis curve measured in experiment,and the stiffness degeneration characteristics of every storey of the frame were analyzed.Finally the accumulated damage was analyzed with the damage assessment model.It is shown that the seismic behavior of this frame of unequal storey height with specially shaped columns is generally good,but the bottom of first floor column is a weak part,which should be paid more attention in design,and the restoring force model derived from this experiment can be seen as a valuable guide for design and non-linear finite element analysis for this kind of structure.

Seismic Behavior of Specially Shaped Column Joints with X-Shaped Reinforcement

To investigate the seismic behavior of specially shaped column joints with X-shaped reinforcement,two groups of specimens with or without X-shaped reinforcement in joint core region were tested under constant axial compression load and low reversed cyclic loading,which imitated low to moderate earthquake force.The seismic behavior of specially shaped column joints with X-shaped reinforcement in terms of bearing capacity,displacement,ductility,hysteretic curve,stiffness degradation and energy dissipation was studied and compared to that without Xshaped reinforcement in joint core region.With the damage estimation model,the accumulated damage was analyzed.The shearing capacity formula of specially shaped column joints reinforced by X-shaped reinforcement was proposed with a simple form.The test results show that X-shaped reinforcement is an effective measure for improving the seismic behavior of specially shaped column joints including deformation behavior,ductility and hysteretic characteristic.All specimens were damaged with gradual stiffness degeneration.In addition,X-shaped reinforcement in the joint core region is an effective way to lighten the degree of cumulated damage.The good seismic performance obtained from the specially shaped column joint with X-shaped reinforcement can be used in engineering applications.The test value is higher than the calculated value,which indicates that the formula is safe for the design of specially shaped column joints.

Special Column for Petroleum Geology & Geophysics:State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum

The State Key Laboratory of Petroleum Resources and Prospecting in China University of Petroleum （Beijing） was designated to be a state key laboratory by the Ministry of Science and Technology in 2007. It was founded on the basis of the Key Laboratory of Hydrocarbon Accumulation Mechanisms of the Ministry of Education and CNPC Key Laboratory of Geophysics. Professor Hao Fang serves as the director of the laboratory. His main research interest is in hydrocarbon accumulation mechanisms.

Preface to Special Column:Flow Battery

The transition of the current energy infrastructure from fossil fuels to renewable energy sources is critical to the continuous prosperity of our society and economy. In order to accelerate the extensive adoption of the sustainable energy sources, challenges of intermittence and instability from the renewables must be resolved. Theretbre, large-scale energy storage technologies, especially flow batteries, have attracted more and more attention, mainly because flow batteries own very intriguing characteristics of independently tuned power and capacity, high safety, high efficiency, long cycle life, flexible modular design, and low cost.

Preface for the Special Column of Gas Hydrates

Gas hydrate （or Hydrate）, is also known as cage-shaped inclusion （Clathrate）. It is ice-like, non-chemical cage-shaped crystal compound, composed of the gas and small water molecules on certain conditions （appropriate temperature, pressure, gas saturation, water salinity, pH, etc.）. It can be represented with M-r^H20, in which M stands for gas molecules of hydrate, and n is the number of water molecules. Small-molecule gases CH4, C2H6, C3H8, C4Hlo equivalent homologue, as well as CO2, N2, H2S, etc., can form a single hydrate or multi-component of gas hydrate. Perhaps the most important gas hydrate is natural gas hydrate, which contains more than 99% methane molecules. So the natural gas hydrate is usually called methane hydrate.

Preface for the Special Column of Methane Transformation

Methane is the main constituent of natural gas, coal-bed gas, landfill gas and methane hydrate resources. These resources may be used more efficiently as clean fuels or as chemical feedstocks if methane can be effectively transformed into liquid fuels or chemicals. However, methane only possesses C-H bonds and is a very stable organic molecule hard to functionalize. The C-H activation, particularly the selective functionalization of C-H bonds in saturated hydrocarbons, remains a difficult challenge in chemistry. The present technology for chemical utilization of methane involves the steam reforming of methane to synthesis gas and the subsequent transformation of synthesis gas to methanol or hydrocarbon fuels via methanol synthesis or Fischer-Tropsch synthesis. However, the steam reforming of methane is a high-cost process. The development of more efficient and economical processes for methane transformation is a dream of all chemists and chemical engineers. I think that this is also one of the most important themes of the Journal of Natural Gas Chemistry.

Preface for the Special Column of the INRET 2006

I would like to take this opportunity to thank the editorial board of Journal of Natural Gas Chemistry for allowing me to write a preface for this special column. The articles appearing in this section are specially selected from the First International Conference on Natural Resources Engineering and Technology 2006 （INRET 2006）. In line with the theme of JNGC, the selected articles are focused on natural gas or low hydrocarbon conversions to important chemicals, fuels and materials. The conference was held on July 24-25, 2006 in Marriott Putrajaya, Malaysia. It was organized by the Chemical and Biotechnology （ChemBio） Focus Group, under the Research Management Centre, Universiti Teknologi Malaysia.

A special column highlighting young scientists at Institute of Chemistry, Chinese Academy of Sciences (ICCAS)

Just seeing off the BOth anniversary of the Institute of Chemistry, Chinese Academy of Sciences （ICCAS）, we are here with pleasure to conduct A Special Column for Young Scientists at ICCAS published in Chinese Chemistry Letters （CCL） endeavoring to disseminate positive energy of several enthusiastic chemists and spread their recent research to the global scientific community.

Preface for Special Column on Automotive Steel

It is believed that steels are still the most important materials for automobile in the foreseeable future because of the advantages in performance, cost, tolerance, fabrication, and recycling, etc. Over decades, a variety of steels are developed and widely used in the car body, from low carbon steel to IF steel, BH steel,

Editor Profiles: Guest Editor of Special Column on Targeted Cancer Therapy

Dr.Guan Chen previously worked in Sun Yat-sen University and German cancer research Center as well in Dana-Farber focused on investigating on biochemical mechanisms involved in cancer drug response by discovering Thaliblastine as a novel and non-toxic

Editor Profile: Guest Editor of Special Column on Molecular Imaging and Theranostics

Dr. Wei Lu is a professor of School of Pharmacy at Fudan University,Shanghai,China.He received his Bachelor of pharmaceutical sciences in 2000 and Ph.D.of pharmaceutics in 2005from Fudan University.After graduation,he worked as a lecturer at Fudan University(2005–2006).Dr. Lu took his post-doctoral training of molecular imaging at Department of