What are the differences between the concept of sonication and ultrasonication?

What's the difference between OCP and OCV in electrochemistry?

As undergraduate students, not everyone gets the same opportunity to involve in research. So, how about, they choose a topic, read 7/8 papers on it, find a research gap, and present it in a conference as a poster? Practically, they are not working in the lab, just compiling and maybe summarizing the existing knowledge. They do not have any research fimdings of their own.

Hi,

I am preparing porous Carbon using some porogen.....After calcination, I need to remove the porogen by using HCL( 2M usually) but the thing is what procedure should I use either sonication or stirring? can the pores of carbon be affected based on our procedure to remove the porogen? Thanks in advance

In doing DPPH antioxidant assay, from sample preparation to experimentation, there are number of ways light may interact with DPPH. How much effect will this have in the sensitivity of this protocol?

What are the ways to minimize the interaction of light in this protocol?

In Paper based assays, how can we optimize this protocol with maximum sensitivity?

Hello Everyone,

Can someone who successfully synthesized Pt on Ti3C2 MXenes that works for ORR in acidic media share some advice?

I have been trying to synthesize Pt NPS on delaminated Ti3C2 MXenes for PEM fuel cell oxygen reduction reaction (ORR) but I have no success so far. Kind of. XRD shows peaks for Pt and Ti3C2 but when I measure in a rotating disc electrode (RDE) in 0.1 M perchloric acid, I get no performance. CV is basically flat with no visible peaks (there are peaks but at microA/cm2 levels compared to the literature which shows around 2 mA/cm2 like Pt/C) and LSV does not go to -6 mA/cm2 value. Best I got so far was about -4 mA/cm2 at 1600 rpm.

I used both suspension and freeze dried MXenes and H2PtCl6 (the bottle was opened about a year ago at this point). Methods I have tried so far;

1) Self-reduction at RT: XRD shows no Pt peaks. No activity in CV, flat line.

2) NaBH4 assisted reduction at RT and 60 C: I prepared NaBH4 solution with pure DI water and in 1 M NaOH. XRD shows Pt peaks, but performance is horrible.

3) Polyol at 165 C: I was really hopeful with this one because this method was the the only one I actually got nicely working Pt/C. However, when I tried with Ti3C2, XRD shows no peaks and there's no electrochemical activity, at all.

4) Hydro- and Solvothermal methods: I tried in pure DI water, DI+EG, EG, DMF+EG mixtures, with different pH values, different reaction times, precursor loadings, PVP loadings, etc. XRD shows Pt peaks but I don't get any activity, at all. When I tried with carbon, it was also the same. XRD shows Pt peaks on C, but no electrochemical activity.

5) Wet impregnation: I used the pure Pt NPs I synthesized in DMF+EG as a solvothermal method, because those Pt NPs worked good. I used 8 mg Ti3C2 and 2 mg PT NPs (to get 20% Pt loading). I dispersed them in acetone for 1 hour and stirred in a beaker at 60 C until completely dry (we don't have a rotavap). I thougth this would work because the pure Pt NPs worked well. However, I didn't get a nice performance again.

We even tried using different batches of MAX phases that have different surface defects to synthesize our MXenes, no luck in terms of ORR performance. We synthesize our MXenes with HCl + LiF mixture and based on the other studies we do in the group, MXenes are working great.

In case of QD film, FRET phenomenon occur , Donor QD transfer energy to acceptor QD molecule. How that transferred energy is utilized by the acceptor molecule? is there any quantitative relation or equation which can tell us the utilization of that energy by the acceptor molecule?

Dear all,

I have been trying to gateway clone two genes, both around 3.2kb in size. However, I am running into a peculiar issue where my colony PCR is positive but once I isolate the plasmid, the insert is not there. For both genes this issue is coming up after the BP reaction transformation. I am using pDONR221. I have also set up a control PCR with my gene primers and pDONR to see if there was any non specific binding but that is not the case. I had previously cloned a 1.2kb gene in the same vector so I am wondering if this is an issue due to the size of the genes.

a small protein (~5KDa) is tagged with HA chromosomally. On doing western blotting and probing blot with anti HA antibody, the protein is showing band at ~13 kDa whereas expected size is ~6 kDa. Resolving gel used is 15%. How to resolve this problem?

I have performed gradient PCR to confirm the annealing temperature for the designed RT-PCR primers. I have set up gradient temperature with difference of 10 degrees from 45-55 degree and 50- 60. The melting temperature that was given in the primer sheet lies in gradient limit set. the gel electrophoresis result showed double bands or multiple bands at every temperature. i have attached a gel picture of the same.

Any suggestions on how to make it right is appreciated.

Thank you in advance.