Is it possible to obtain a negative cronbach alpha?

Good evening everyone. If a questionnaire has 4 factors measuring different constructs as for example CAMI questionnaire measuring attitudes toward the mentally ill that has four factors:...

18 February 2021 3,223 3 View

What is exact impact of pH on preparation method of nanoparticles? why some nanoparticles are synthesized in ACIDIC pH while others in alkaline pH?

I am trying to prepare Cerium oxide nanoparticles. literature suggested the acidic pH of the reaction. what is the reason? what is the mechanism if so

28 November 2020 8,825 2 View

Estimate / Predict remaining useful life of a bearing without data of previous failure?

Hello, I am trying to write a program in Matlab to estimate the remaining useful life of a bearing without data of a previous failure. Do you think this is possible? I was thinking to use the...

27 November 2020 9,863 3 View

Two way ANOVA with non normal data?

Good afternoon everyone. I would like to know your oppinion or advise for the following: I would like to compare the results of a variable measured with a likert scale. I have two (or three)...

19 October 2020 4,564 4 View

Comparing two independent groups with very different sample size?

Hello eveyone. I would like to know your oppinion on the following. Do you think that it is adequate to compare two groups with very different sample size and non normal sample distribution? for...

19 October 2020 8,475 4 View

Total Alkaloid Content?

Can someone suggest a simple calorimetric assay protocol for determination of total alkaloid content of plant extract?

10 September 2020 8,835 3 View

What are the environmental problems caused by phosphorus pollution ?

What are the environmental problems caused by phosphorus pollution ?

27 July 2020 948 34 View

What are the harmful effects of nitrates higher concentration on public health?

15 July 2020 3,900 10 View

What are the best methods of water management in the case of an agricultural drought ?

The importance of water resources is evident, and its management through all levels is imperative, especially in arid and semi-arid countries where water demand is highly required for irrigation...

10 July 2020 6,153 7 View

What are the advantages of using renewable energies for the desalination of seawater?

what are the advantages of using renewable energies for the desalination of seawater?

28 June 2020 6,093 3 View

Waters 2707 HPLC autosampler problem?

I am using a 2707 waters HPLC device. When I try to inject a sample, it says missing plate or rack. I changed the needle and calibrated its position but I still get the same problem. I even get...

02 March 2021 1,408 1 View

Should we change media after1st 6hrs after plating HUVEC bought from INVITROGEN?it's not recomended by invitrogen.Will DMSO present in stock matter?

We have HUVEC bought from Invitrogen. Cat no -C-003-5c. while first plating the cells we have bought the protocol suggests not to centrifuge the cell with media to remove the DMSO. Should we...

02 March 2021 3,713 2 View

How to normalise data on OPM package from R Studio ?

Good afternoon, I recently used OmniLog from BIOLOG for my experimentations : I tested the metabolism of different strains on 2 types of plates. I have 16 strains of 3 different groups...

02 March 2021 3,584 1 View

What are the countries most affected by extreme rainfall as a result of climate change?

Increased heat, drought and insect outbreaks, all associated to climate change, have increased wildfires. Decreasing water supplies, declined agricultural yields, health impacts in cities owing to...

01 March 2021 7,168 9 View

What is recommended for solid domain in ANSYS FLUENT?

Should I mesh the solid domain ? or should I use wall thickness? or Shell conduction? for Heat Transfer between two fluids of a Heat Exchanger. what is recommended?

01 March 2021 9,785 3 View

Heat exchanger with liquid Nitrogen as coolant?

I want to cool Natural Gas from 195 Kelvin to 138 Klevin in a heat exchanger by using liquid nitrogen as the coolant medium. When entering the heat exchanger, the liquid nitrogen will have a...

01 March 2021 6,450 5 View

How can i resolve the "final solutuin is not converged" error in Comsol for my heat transfer simulation??

I have been trying to simulate heat transfer problem in Comsol 5.5 for long time but it always throw an error stating: "Failed to find a solution. Maximum number of Newton iterations...

28 February 2021 8,626 3 View

Benefits of the 24 welled plate?

We have always used the 96 welled plate, the 48 welled plate but apparently there is much evidence on the 24 welled plate and above all its benefits.It states it is the same you would use on ELISA...

28 February 2021 1,149 1 View

Can bacterial suspension be pipetted directly onto petri dish and agar poured onto it?

Hi, recently I encountered a protocol for plating which was not the usual method I have been practicing (pour LB agar onto plate, allow it to solidify, pipette bacterial suspension onto plate,...

28 February 2021 7,292 3 View

Exit velocity of natural gas from pressurized tank?

Hi Guys. I'm a mechanical engineer and have a bit trouble, would be very glad if you could help me with my questions. I have a pressurized tank which contains Natural Gas at 200 Bar and 293...

26 February 2021 6,253 3 View