60+ Scientist Interview Questions and Answers

The minimum temperature of any substance that we could reach and use for practical purposes is absolute zero, which is -273.15 degrees Celsius or 0 Kelvin.

• The minimum temperature is known as absolute zero.

• It is the lowest possible temperature that can be reached.

• At absolute zero, all molecular motion ceases.

• Practical applications include cryogenics and superconductivity.

• Examples of practical uses are in medical imaging, particle accelerators, and space exploration.

The answer to the question is provided below.

• Reverse osmosis treatment can be made cheaper at home by using low-cost membranes and energy-efficient systems.

• Zero discharge in industries can be achieved through the implementation of advanced treatment technologies like membrane filtration and evaporation.

• BOD (Biochemical Oxygen Demand) measures the amount of oxygen consumed by microorganisms during the decomposition of organic matter, while COD (Chemical Oxygen Demand) measures...read more

I would like to design electronic components with heat transfer applications.

• I have a strong interest in electronics and how heat can be managed in electronic systems.

• I enjoy working on projects that involve designing and optimizing electronic components for efficient heat dissipation.

• I have experience in conducting thermal analysis and simulations to ensure proper heat transfer in electronic devices.

• I find it fascinating to explore innovative ways to improve heat dissipation...read more

Humidity ratio is measured using two types of instruments: psychrometers and hygrometers.

• Psychrometers measure humidity ratio by comparing the readings of two thermometers: a dry-bulb and a wet-bulb thermometer.

• Hygrometers measure humidity ratio using various principles such as electrical resistance, capacitance, or condensation.

• A 1 ton refrigerator refers to the cooling capacity of the refrigerator, which is equivalent to removing 12,000 British Thermal Units (BTUs) of heat ...read more

There are three laws of thermodynamics. Each law has specific applications. dB Amp is not related to thermodynamics.

• The first law of thermodynamics, also known as the law of energy conservation, states that energy cannot be created or destroyed, only transferred or transformed.

• The second law of thermodynamics states that the entropy of an isolated system always increases over time.

• The third law of thermodynamics states that as the temperature approaches absolute zero, the ent...read more

Yes, metal prototypes can be made through various processes.

• Metal casting: Using molds to create metal prototypes.

• Metal additive manufacturing: Using 3D printing to build metal prototypes layer by layer.

• Metal machining: Cutting, drilling, or shaping metal to create prototypes.

• Metal injection molding: Injecting molten metal into a mold to form prototypes.

• Metal extrusion: Forging metal through a die to create prototype shapes.

• Metal sheet forming: Bending or shaping metal sheets...read more

The choice between Al and Mg for designing depends on the specific requirements and constraints of the project.

• Aluminum (Al) is lightweight, corrosion-resistant, and has good thermal conductivity, making it suitable for applications where weight reduction is important, such as aerospace.

• Magnesium (Mg) is even lighter than aluminum, but it has lower strength and is more prone to corrosion. It is commonly used in automotive components to reduce weight and improve fuel efficienc...read more

Compensating bendback in sheetmetal can be achieved through various methods.

• Use a larger bend radius to reduce the amount of bendback

• Implement a pre-bend or over-bend technique to counteract the bendback

• Utilize specialized tooling or fixtures to control the bending process

• Apply heat or annealing to the sheetmetal to reduce its springback tendency

• Consider using different materials or alloys with lower springback characteristics

Battery management is required in Lithium Ion battery solutions to ensure safety, optimize performance, and prolong battery life.

• Lithium Ion batteries are prone to overheating and can catch fire or explode if not properly managed.

• Battery management systems monitor and control various parameters such as voltage, current, temperature, and state of charge.

• These systems prevent overcharging, over-discharging, and overcurrent situations that can damage the battery or reduce its ca...read more

Nitrosamines are impurities that can form in products due to chemical reactions involving amines and nitrites.

• Nitrosamines are a class of chemical compounds that contain a nitroso group (-NO) bonded to an amine group (-NH2).

• They can form in products such as pharmaceuticals, cosmetics, and food during manufacturing, storage, or processing.

• The formation of nitrosamines typically requires the presence of amines and nitrites, which can react under certain conditions.

• Scientific ju...read more

I have used various softwares for data analysis including R, Python, Excel, and SPSS.

• R

• Python

• Excel

• SPSS

Different rapid prototyping processes include 3D printing, CNC machining, and injection molding.

• 3D printing: Additive manufacturing technique that creates objects layer by layer using a digital model.

• CNC machining: Computer-controlled subtractive manufacturing process that uses pre-programmed tools to remove material from a solid block.

• Injection molding: Process of injecting molten material into a mold cavity to create a solid object.

I have extensive experience in operating fermentors for various scientific experiments and research projects.

• I have operated fermentors in a laboratory setting for over 5 years.

• I am proficient in setting up and calibrating fermentors for different types of cultures.

• I have monitored and controlled fermentation parameters such as temperature, pH, and agitation.

• I have experience in troubleshooting and resolving issues that may arise during fermentation processes.

• I have successfu...read more

Normal phase and Reverse phase are two types of chromatography techniques used for separation of molecules based on their polarity.

• Normal phase chromatography uses a polar stationary phase and a non-polar mobile phase, while reverse phase chromatography uses a non-polar stationary phase and a polar mobile phase.

• Normal phase is used for separation of polar compounds, while reverse phase is used for separation of non-polar compounds.

• Examples of normal phase chromatography inclu...read more

Dilute a 2M sulfuric acid solution to 0.1M by adding water in a controlled manner.

• Calculate the dilution factor: 2M to 0.1M is a dilution factor of 20.

• Use the formula C1V1 = C2V2, where C1 is the initial concentration, V1 is the initial volume, C2 is the final concentration, and V2 is the final volume.

• For example, to make 1L of 0.1M solution, use 50mL of 2M sulfuric acid and dilute it with 950mL of water.

• Always add acid to water, not water to acid, to prevent exothermic react...read more

Acids can be converted to amines via reductive amination, a process involving amine formation from carbonyl compounds.

• Reductive amination involves the reaction of an aldehyde or ketone with an amine.

• The process typically uses a reducing agent like sodium cyanoborohydride (NaBH3CN).

• Example: Converting acetic acid (CH3COOH) to ethylamine (CH3CH2NH2) via the formation of an intermediate.

• This reaction is often catalyzed by acids to facilitate the formation of the imine intermedia...read more

There are several types of counters that can be used to design a divide by 5 counter.

• Ripple counter

• Synchronous counter

• Johnson counter

• Ring counter

RDC guidelines for validation differ from bz guidelines in key aspects.

• RDC guidelines focus on analytical validation of biomarkers

• Bz guidelines focus on clinical validation of biomarkers

• RDC guidelines emphasize on assay performance characteristics

• Bz guidelines emphasize on clinical utility and patient outcomes

• RDC guidelines require rigorous statistical analysis

• Bz guidelines require validation in multiple independent cohorts

The last propulsion system I built was a hybrid rocket engine for a small satellite.

• Developed a hybrid rocket engine using a combination of solid fuel and liquid oxidizer

• Tested the engine for efficiency and performance

• Integrated the propulsion system into a small satellite for orbital maneuvers

Genes are selected based on their potential role in a specific biological process or disease.

• Identify the biological process or disease of interest

• Consult existing literature and databases to identify candidate genes

• Prioritize genes based on their known function and relevance to the process/disease

• Use genetic engineering techniques to knock out the selected genes

• Analyze the resulting phenotype to confirm the gene's role

Technical issues during downstream processing can be solved by identifying the root cause and implementing appropriate solutions.

• Identify the root cause of the issue

• Implement appropriate solutions such as adjusting process parameters or changing equipment

• Perform thorough testing and validation of the solution

• Document the issue and solution for future reference

Wind tunnels are used to study the effects of air on objects. Materials and their properties play a crucial role in wind tunnel experiments.

• Wind tunnels are used to simulate the flow of air around objects, allowing scientists to study aerodynamics.

• Different materials have different properties that can affect the results of wind tunnel experiments.

• Materials with low drag coefficients, such as smooth metals, are often used in wind tunnel testing.

• Understanding the properties of ...read more

Agronomic practices refer to the methods used to cultivate crops and improve their yield and quality.

• Crop rotation

• Tillage practices

• Fertilization

• Irrigation

• Pest and disease management

• Harvesting techniques

Post translational modification refers to the chemical modification of a protein after it has been synthesized.

• Common modifications include phosphorylation, glycosylation, and acetylation.

• These modifications can alter the protein's function, stability, and localization.

• Examples of post translational modification include the addition of a phosphate group to a serine or threonine residue, or the addition of a sugar molecule to an asparagine residue.

• Post translational modificati...read more

Cytotoxicity assays, ELISA, Western blot are techniques used in molecular biology and biochemistry.

• Cytotoxicity assays are used to determine the toxicity of a substance on cells.

• ELISA is used to detect and quantify specific proteins or antibodies in a sample.

• Western blot is used to detect specific proteins in a sample using antibodies.

• Other techniques include PCR, gel electrophoresis, and flow cytometry.

• These techniques are commonly used in research and diagnostic laboratorie...read more

Rectifying quarries involves methods to restore and rehabilitate mined land for ecological and community benefits.

• Revegetation: Planting native species to restore biodiversity and stabilize soil.

• Water management: Creating ponds or wetlands to enhance local ecosystems.

• Landform restoration: Reshaping the land to its natural contours to prevent erosion.

• Community engagement: Involving local communities in planning and restoration efforts.

• Monitoring: Regular assessment of ecologic...read more

Capsules are made of gelatin shells filled with powder or liquid, while tablets are compressed powder or granules.

• Capsules are easier to swallow than tablets.

• Capsules can be opened and mixed with food or drink, while tablets cannot.

• Tablets can be scored for easier splitting, while capsules cannot.

• Capsules are more expensive to manufacture than tablets.

• Examples of capsules include Advil Liqui-Gels and Tylenol Gelcaps, while examples of tablets include aspirin and ibuprofen tab...read more