Assuming that you are taking an active part in trying to eradicate the invasive species from your area, what information do you need to adequately understand and address pests and pathogens? (e.g. information on the ecology, spread and effects of important pest and pathogen; information on how to identify them; information on strategies for preventing their spread and harmful effects)
In: Other
Heptadecane (A) is being absorbed from a dilute gaseous mixture with 1-Octyne (B) by Hydrochloric Acid in a wetted wall column. The following experimental data are available:
a. Inside diameter = 43 mm
b. Average gas velocity = 250 cm/s
c. Gas Temperature = 50 °C
d. Total Pressure = 1 atm
At a certain point in the column, the partial pressure of A in B is 30 mmhg and the mol fraction of Heptadecane at the gas side of the interface is 0.009. Predict the mass diffusivity using Fuller et. al. equation. Calculate the rate of absorption of A.
In: Other
Some mountain glaciers are advancing (e.g. those of the Karakoram range in the Greater Himalaya). How can mountain glaciers advance while the global mean temperature is increasing?
In: Other
What would the intensity of shaking be on the Modified Mercalli scale?
| a. |
I |
|
| b. |
II |
|
| c. |
III |
|
| d. |
IV |
|
| e. |
V |
|
| f. |
VI |
|
| g. |
VII |
|
| h. |
VIII |
|
| i. |
IX |
|
| j. |
X |
|
| k. |
XI |
|
| l. |
XII |
In: Other
Compare the maximum thickness of the boundary layer that develops due to uniform flow past a flat plate when the fluid is
(a) air, (b) water, (c) glycerol.
The plate length is 3 m and the approaching fluid velocity is 4 m/s.
In: Other
For the elementary gas phase reaction H+C2H4 ®C2H5, the second-order rate constant
varies with temperature in the following way:
T / K 198 298 400 511 604
1012 k/(cm3molecule-1s-1) 0.20 1.13 2.83 4.27 7.69
a) Use the data to calculate the activation energy, Ea, and the pre-exponential factor, A, for the reaction.
b) The simple collision theory of bimolecular reactions yields the following expression for the rate constant:
k = (8kT/p m)1/2 sexp(-Ea/RT)
where mis the reduced mass of the reactants and s is the reaction cross section.
i) Interpret the role of the three factors in this expression.
ii) Use the answer to part a) to estimate s for the reaction at 400K.
iii) Compare the value obtained with an estimate of 4.0x10-19 m2 for the collision cross section.
[Take the atomic masses of H and C to be 1.0 amu and 12 amu, respectively.]
In: Other
Below is a list of examples of benefits that ecosystems provide to people. Match each benefit with the correct category of ecosystem services.
| A. Regulating services |
| B. Provisioning services |
| C. Supporting services |
| D. Cultural services |
| selectABCD | 1. Before Europeans came, Michigan had a large area of old growth beech-maple forest near its southern border. Except for a small area where the loggers ate lunch, the entire beech-maple forest ecosystem was logged in the 1800’s. Only the loggers’ picnic area remains as a small remnant (~300 acres) of the great beech-maple forest. That remnant is now called Warren Woods. The ancient beech trees in Warren Woods are about 125 feet tall. The soil is rich, and the ground is covered with colorful wildflowers. For many years, a sign at the entrance stated, “Welcome to the forest primeval.” People come to experience walking through an ancient forest that feels like a cathedral. |
| selectABCD | 2. Since about 3 billion years ago, miniscule aquatic bacteria have been performing photosynthesis, releasing oxygen as a byproduct. They and their descendants, called chloroplasts, which live inside the cells of algae and land plants, produced, and continue to produce, nearly all the oxygen in our atmosphere. They also capture carbon from the atmosphere and incorporate it into carbohydrates, fats, oils, protein, and other types of food. All the carbon in all of our foods came to us by way of these photosynthetic bacteria and their descendants. |
| selectABCD | 3. The dead remains of leaves, insects, worms, and other organisms contain thousands of different kinds of organic (carbon-containing) and inorganic chemicals. Plants are unable to use these chemicals until the dead remains are chemically transformed during the decay process. Decay is carried out by various types of fungi, bacteria, and other microorganisms. Without the chemical transformations that take place during the decay process, living plants would quickly use up all the available nutrients in the soil and die. Without decay, there would be no plants. Without plants, there would be no animals. |
| selectABCD | 4. Large lakes are fed by incoming streams. When the forest is intact, the streams are deep and the water is cold and clear. Fish and other animals do better in cold water because cold water can hold more oxygen. The presence of the lake also causes a moderation in the air temperature near the lake. |
In: Other
A vertical vessel with an internal diameter of 84” has a hemispherical head at the top and an ellipsoidal head of 2:1 at the bottom. The construction material has a maximum allowable stress of 8700 psi at its design temperature. The operating pressure is stated as 48 psig. The overall height of the vessel is 38‟ and a joint efficiency of 1.0 is used.
) Determine the wall thickness of each part of the vessel.
b) If a corrosion allowance of 2 mm is being fixed by the user, determine the wall thicknesses and part MAWPs for each part of the vessel and what is the vessel MAWP?
In: Other
In: Other
.Define the terrestrial age of a meteorite and explain, in your own words, how this is determined. (About 200 words)
In: Other
In: Other
give your theory or idea on why time is 24 hours, why are their 60 minute's in an hour and 60 seconds in a minute. Why did early civilizations pick these particular numbers for time. Give your response with a paragraph explaining your theory, idea and or argument.
In: Other
Describe how humans have affected the numerous pathways and reservoirs in the carbon cycle that have contributed to climate change. Find three examples where positive feedback in the environment is likely contributing more carbon dioxide to the atmosphere that is not a result of human activities.
In: Other
Discuss the factors contributing to Antarctica’s extreme cold. Discuss why Antarctica is significant to studying global climate change. Discuss the changes of Alpine glaciers and their causes.
In: Other
(a) Tobaco Berhad, with the Ringgit Malaysia as its functional currency, purchases plant from a foreign entity for $18 million on 31 May 2019 when the exchange rate was $2 to RM1. The entity also sells goods to a foreign customer for $10.5million on 30 September 2019, when the exchange rate was $1.75 to RM1. At the entity’s year end of 31 December 2019, both amounts are still outstanding and have not been paid. The closing exchange rate was$1.5 to RM1. Required: Explain the accounting treatment for both sale and purchases transactions for Tobacco Berhad.
In: Other