3/20/2020
It happened many times: you got see your ideas published by someone else. I feel encouraging.
11/8/2019
There are so many disturbing things in your life hindering your way on Science.
4/29/2017
Publishing papers is not equal to doing Science; Not publishing papers is equal to not doing Science.
发文章不等于做研究；不发文章一定等于不做研究。
11/27/2016
“Today the network of relationships linking the human race to itself and to the rest of the biosphere is so complex that all aspects affect all others to an extraordinary degree. Someone should be studying the whole system, however crudely that has to be done, because no gluing together of partial studies of a complex nonlinear system can give a good idea of the behavior of the whole.”
Quote by Murray Gell-Mann
11/21/2016
I hope I could say so one day: I am working on solving scientific problems,especially high-quality ones. I am not willing to take some TEM images to help mediocre work to get published.
9/26/2015
Think, before ,during and after the experiment/calculation.
9/15/2015
These are fundermental issue for lots of people but they are also generally existed:
(1) TEM results can be not interpreted without knowledge of electron microscopy.
(2) TEM work has to be properly done, knowing what you are doing!
7/1/2016
Here is a link about how to measure the collection angle of EELS: Link
or
http://www.microscopy-analysis.com/editorials/editorial-listings/how-optimize-your-eels-experiments-adjusting-collection-angle-your
5/12/2016
Google scholar is a convenient way to search literatures in certain fields. If you got a personal citation page at google scholar,
it is better to remove the papers from someone else in your webpage.
4/29/2016
"The CV of failures"!
It is a fantastic idea. Practised by Prof. Johannes Haushofer, an assistant professor at Princeton, check it out here:
http://www.hrgrapevine.com/markets/hr/article/2016-04-28-professors-cv-of-failures-goes-viral
and here:
http://www.princeton.edu/joha/Johannes_Haushofer_CV_of_Failures.pdf
For his normal CV, check it here:
http://www.princeton.edu/joha/Johannes_Haushofer_CV.pdf
10/29/2015
The bureaucratic regulations kill the competitive power, in either industry or academia.
1/27/2015 Polarization, Activation polarization and Over-potential in electrochemical system
Electrode reactions are assumed to induce deviations from equilibrium due to the passage of an electrical current through an electrochemical cell causing a change in the working electrode (WE) potential. This electrochemical phenomenon is referred to as polarization. In this process, the deviation from equilibrium causes an electrical potential difference between the polarized and the equilibrium (unpolarized) electrode potential known as over-potential.
In general, the activation polarization is basically an electrochemical phenomenon related to a charge-transfer mechanism, in which a particular reaction step controls the rate of electron flow from a metal surface undergoing oxidation.
(from: Electrochemistry chapter 3 from TU Delft OpenCourseWare)
1/22/2015 Useful links about some basic conception:
Cyclic voltammetry:
http://en.wikipedia.org/wiki/Cyclic_voltammetry
12/17/2014, The best description of Lithium ion battery, from the abstract of Goodenough et al, J. Am. Chem. Soc. 2013, 135, 1167−1176
Each cell of a battery stores electrical energy as chemical energy in two electrodes, a reductant (anode) and an oxidant (cathode), separated by an electrolyte that transfers the ionic component of the chemical reaction inside the cell and forces the electronic component outside the battery. The output on discharge is an external electronic current I at a voltage V for a time Δt. The chemical reaction of a rechargeable battery must be reversible on the application of a charging I and V. Critical parameters of a rechargeable battery are safety, density of energy that can be stored at a specific power input and retrieved at a specific power output, cycle and shelf life, storage efficiency, and cost of fabrication. Conventional ambient-temperature rechargeable batteries have solid electrodes and a liquid electrolyte. The positive elec- trode (cathode) consists of a host framework into which the mobile (working) cation is inserted reversibly over a finite solid−solution range. The solid−solution range, which is reduced at higher current by the rate of transfer of the working ion across electrode/electrolyte interfaces and within a host, limits the amount of charge per electrode formula unit that can be transferred over the time Δt = Δt(I). Moreover, the difference between energies of the LUMO and the HOMO of the electrolyte, i.e., electrolyte window, determines the maximum voltage for a long shelf and cycle life. The maximum stable voltage with an aqueous electrolyte is 1.5 V; the Li-ion rechargeable battery uses an organic electrolyte with a larger window, which increase the density of stored energy for a given Δt. Anode or cathode electrochemical potentials outside the electrolyte window can increase V, but they require formation of a passivating surface layer that must be permeable to Li+ and capable of adapting rapidly to the changing electrode surface area as the electrode changes volume during cycling. A passivating surface layer adds to the impedance of the Li+ transfer across the electrode/electrolyte interface and lowers the cycle life of a battery cell. Moreover, formation of a passiva- tion layer on the anode robs Li from the cathode irreversibly on an initial charge, further lowering the reversible Δt. These problems plus the cost of quality control of manu- facturing plague development of Li-ion rechargeable batteries that can compete with the internal combustion engine for powering electric cars and that can provide the needed low-cost storage of electrical energy generated by renewable wind and/or solar energy. Chemists are con- tributing to incremental improvements of the conventional strategy by investigating and controlling electrode passiva- tion layers, improving the rate of Li+ transfer across electrode/electrolyte interfaces, identifying electrolytes with larger windows while retaining a Li+ conductivity σLi > 10−3S cm−1, synthesizing electrode morphologies that reduce the size of the active particles while pinning them on current collectors of large surface area accessible by the electrolyte, lowering the cost of cell fabrication, designing displacement- reaction anodes of higher capacity that allow a safe, fast charge, and designing alternative cathode hosts. However, new strategies are needed for batteries that go beyond powering hand-held devices, such as using electrode hosts with two-electron redox centers; replacing the cathode hosts by materials that undergo displacement reactions (e.g. sulfur) by liquid cathodes that may contain flow-through redox molecules, or by catalysts for air cathodes; and developing a Li+ solid electrolyte separator membrane that allows an organic and aqueous liquid electrolyte on the anode and cathode sides, respectively. Opportunities exist for the chemist to bring together oxide and polymer or graphene chemistry in imaginative morphologies.