Using MicroMass, API MS, the negative mode capillary voltage stuck at 0?

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How to understand this crystallographic phenomenon of low temperature crystals in zeolite?

During low-temperature testing, new diffraction peaks that appear could be indicative of several phenomena. In one of our tests, we observed notable new peaks around 40° and 45° in a specific...

06 August 2024 726 3 View

How can I find writers for drafting, submitting, and publishing papers?

Looking for paper collaboration writers： Collaboration Model 1: 1.1 Based on the chosen topic, complete the paper writing, select an SCI or SSCI Q1 journal, submit using my QRCID, and complete...

27 July 2024 8,965 1 View

Cuáles fueron las tendencias en investigaciones en arquitectura, urbanismo y patrimonio edificado en decadas del 2000 al 2020?

Cuáles fueron las tendencias en investigaciones en arquitectura, urbanismo y patrimonio edificado en decadas del 2000 al 2020? Porque requiero conocer tesis de posgrado nivel maestría...

24 July 2024 5,494 1 View

Mechanochemistry: ball to powder mass or ball to powder volume?

I run mechanochemical reactions that involves the use of a large amount of catalyst (1:1 molar ratio to the reactant). When I try to understand the effect of amount of catalyst on the reaction, I...

23 July 2024 9,938 1 View

How can I determine if a drug binds to a ribosome using a Cryo-EM map?

Hello, I am searching for the binding position of a drug in a ribosome, based on previous work indicating it binds there. The resolution of the ribosome-drug Cryo-EM map is around 2.5 Å. I've been...

19 July 2024 2,155 0 View

Can anyone recommend a brand of cas9 protein that can be used for in-vivo editing in model animals?

zebrafish and mouse

19 July 2024 9,158 1 View

What happens in snapTotal- seq?

What happens in snapTotal- seq? (Single-cell Total-RNA Profiling Unveils Regulatory Hubs of Transcription Factors https://www.nature.com/articles/s41467-024-50291-3) In this protocol, several RT...

18 July 2024 10,010 0 View

How to cacualte the creep life of polycrystal with CPFEM?

I saw a paper(PHAN V-T, ZHANG X, LI Y, et al. Microscale modeling of creep deformation and rupture in Nickel-based superalloy IN 617 at high temperature [J]. Mechanics of Materials, 2017, 114:...

16 July 2024 8,436 0 View

Does HEK293T cell express RIG1?

Is there any benefit in knocking out the interferon receptor in 293T cells? In the context of creating RNA viruses 📷

13 July 2024 3,382 0 View

The HCP removal rate is lower than usual in concentration step, why?

Hello everyone. I am working on my LV concentration porject, I use 500Kda hollowfiber to do it. The HCP and BSA removal rate is nearly 80%, but last time, I failed to run it. The HCP hasn't been...

11 July 2024 5,380 0 View

• What the possible Persistent Organic Pollutants and Heavy metals present in fluorspar, sediments, and water bodies around its mining area?

Approximate concentrations are require in compared with the WHO permissible limts

11 August 2024 2,723 1 View

Handling Missing Data and Building a Predictive Model with Incomplete Information ?

I am developing a predictive model for a water supply network that involves 20 influencing points. However, I only have historical data for 10 out of these 20 points. I would like to know how to...

10 August 2024 4,005 2 View

Do interactions between biosphere, carbon cycle, & water cycle impact global warming & interaction between atmosphere & hydrosphere?

How do interactions between the biosphere, the carbon cycle, and the water cycle impact global warming and interaction between the atmosphere and the hydrosphere?

09 August 2024 3,291 2 View

Is it true that $\det(V(A))$ may be only $\pm 1$, depending on $n$, for the last symmetric tridiagonal matrix $A$?

One can try to generalize the Vandermonde determinant in the following direction: Let $A$ be any symmetric $n$-order square matrix. Consider its powers' diagonal elements $(A^k)_{ii}$ and...

08 August 2024 6,690 1 View

How can major oxides determined by ICP-MS/ES be normalized to 100% volatile free? How does this connect with LOI?

I am analyzing cherts from different sources found within one specific geologic formation using ICP-MS/ES. My committee was asking this question about my analysis. I was not sure how to answer this

05 August 2024 7,902 3 View

Low-yield gel extraction problem?

I am having an issue with my gel image where my PCR product is not appearing very bright on the gel. When I perform gel extraction, the A260/280 purity value is very low. I used the Qiagen gel...

05 August 2024 9,798 3 View

Usage of internal standards in LC-MS/MS analysis?

Have you ever seen a LC-MS/MS method uses both internal standards and external standards (in matrix matching purpose) but the concentrations of internal standards are outside the calibration curve...

05 August 2024 3,084 6 View

How to Add Missing Water Molecules in Protein-Membrane Simulations?

I have protein-membrane simulations (PDB, PSF, DCD) and have noticed that water molecules near the protein are not visible in the simulations. How can I fix this issue? Is there a way to place the...

04 August 2024 1,200 2 View

Why is nonpoint source pollution potentially more harmful and difference between point and nonpoint sources of water pollution?

01 August 2024 1,180 2 View

How do living organisms play a role in the water cycle and why is nonpoint source pollution potentially more harmful than point source pollution?

01 August 2024 7,061 2 View